A transwell assay that excludes exosomes for assessment of tunneling nanotube-mediated intercellular communication.

PubMed

Thayanithy, Venugopal; O'Hare, Patrick; Wong, Phillip; Zhao, Xianda; Steer, Clifford J; Subramanian, Subbaya; Lou, Emil

2017-11-13

Tunneling nanotubes (TNTs) are naturally-occurring filamentous actin-based membranous extensions that form across a wide spectrum of mammalian cell types to facilitate long-range intercellular communication. Valid assays are needed to accurately assess the downstream effects of TNT-mediated transfer of cellular signals in vitro. We recently reported a modified transwell assay system designed to test the effects of intercellular transfer of a therapeutic oncolytic virus, and viral-activated drugs, between cells via TNTs. The objective of the current study was to demonstrate validation of this in vitro approach as a new method for effectively excluding diffusible forms of long- and close-range intercellular transfer of intracytoplasmic cargo, including exosomes/microvesicles and gap junctions in order to isolate TNT-selective cell communication. We designed several steps to effectively reduce or eliminate diffusion and long-range transfer via these extracellular vesicles, and used Nanoparticle Tracking Analysis to quantify exosomes following implementation of these steps. The experimental approach outlined here effectively reduced exosome trafficking by >95%; further use of heparin to block exosome uptake by putative recipient cells further impeded transfer of these extracellular vesicles. This validated assay incorporates several steps that can be taken to quantifiably control for extracellular vesicles in order to perform studies focused on TNT-selective communication.

Mechanism of gemcitabine-induced suppression of human cholangiocellular carcinoma cell growth.

PubMed

Toyota, Yuka; Iwama, Hisakazu; Kato, Kiyohito; Tani, Joji; Katsura, Akiko; Miyata, Miwa; Fujiwara, Shintaro; Fujita, Koji; Sakamoto, Teppei; Fujimori, Takayuki; Okura, Ryoichi; Kobayashi, Kiyoyuki; Tadokoro, Tomoko; Mimura, Shima; Nomura, Takako; Miyoshi, Hisaaki; Morishita, Asahiro; Kamada, Hideki; Yoneyama, Hirohito; Okano, Keiichi; Suzuki, Yasuyuki; Masaki, Tsutomu

2015-10-01

Although gemcitabine (2',2'-difluorocytidine monohydrochloride) is a common anticancer agent of cholangiocellular carcinoma (CCC), its growth inhibitory effects and gemcitabine resistance in CCC cells are poorly understood. Our aims were to uncover the mechanism underlying the antitumor effect of gemcitabine and to analyze the mechanism regulating in vitro CCC cell gemcitabine resistance. In addition, we sought to identify miRNAs associated with the antitumor effects of gemcitabine in CCCs. Using a cell proliferation assay and flow cytometry, we examined the ability of gemcitabine to inhibit cell proliferation in three types of human CCC cell lines (HuCCT-1, Huh28, TKKK). We also employed western blotting to investigate the effects of gemcitabine on cell cycle-related molecules in CCC cells. In addition, we used array chips to assess gemcitabine-mediated changes in angiogenic molecules and activated tyrosine kinase receptors in CCC cells. We used miRNA array chips to comprehensively analyze gemcitabine-induced miRNAs and examined clusters of differentially expressed miRNAs in cells with and without gemcitabine treatment. Gemcitabine inhibited cell proliferation in a dose- and time-dependent manner in HuCCT-1 cells, whereas cell proliferation was unchanged in Huh28 and TKKK cells. Gemcitabine inhibited cell cycle progression in HuCCT-1 cells from G0/G1 to S phase, resulting in G1 cell cycle arrest due to the reduction of cyclin D1 expression. In addition, gemcitabine upregulated the angiogenic molecules IL-6, IL-8, ENA-78 and MCP-1. In TKKK cells, by contrast, gemcitabine did not arrest the cell cycle or modify angiogenic molecules. Furthermore, in gemcitabine-sensitive HuCCT-1 cells, gemcitabine markedly altered miRNA expression. The miRNAs and angiogenic molecules altered by gemcitabine contribute to the inhibition of tumor growth in vitro.

In vitro and in vivo anti-tumor activities of a gemcitabine derivative carried by nanoparticles

PubMed Central

Sloat, Brian R.; Sandoval, Michael A.; Li, Dong; Chung, Woon-Gye; Lansakara-P., Dharmika S. P.; Proteau, Philip J.; Kiguchi, Kaoru; DiGiovanni, John; Cui, Zhengrong

2011-01-01

Gemcitabine (Gemzar®) is the first line treatment for pancreatic cancer and often used in combination therapy for non-small cell lung, ovarian, and metastatic breast cancers. Although extremely toxic to a variety of tumor cells in culture, the clinical outcome of gemcitabine treatment still needs improvement. In the present study, a new gemcitabine nanoparticle formulation was developed by incorporating a previously reported stearic acid amide derivative of gemcitabine into nanoparticles prepared from lecithin/glyceryl monostearate-in-water emulsions. The stearoyl gemcitabine nanoparticles were cytotoxic to tumor cells in culture, although it took a longer time for the gemcitabine in the nanoparticles to kill tumor cells than for free gemcitabine. In mice with pre-established model mouse or human tumors, the stearoyl gemcitabine nanoparticles were significantly more effective than free gemcitabine in controlling the tumor growth. PEGylation of the gemcitabine nanoparticles with polyethylene glycol (2000) prolonged the circulation of the nanoparticles in blood and increased the accumulation of the nanoparticles in tumor tissues (> 6-fold), but the PEGylated and un-PEGylated gemcitabine nanoparticles showed similar anti-tumor activity in mice. Nevertheless, the nanoparticle formulation was critical for the stearoyl gemcitabine to show a strong anti-tumor activity. It is concluded that for the gemcitabine derivate-containing nanoparticles, cytotoxicity data in culture may not be used to predict their in vivo anti-tumor activity, and this novel gemcitabine nanoparticle formulation has the potential to improve the clinical outcome of gemcitabine treatment. PMID:21371545

Simultaneous Dual Selective Targeted Delivery of Two Covalent Gemcitabine Immunochemotherapeutics and Complementary Anti-Neoplastic Potency of [Se]-Methylselenocysteine

PubMed Central

Coyne, C. P.; Jones, Toni; Bear, Ryan

2015-01-01

The anti-metabolite chemotherapeutic, gemcitabine is relatively effective for a spectrum of neoplastic conditions that include various forms of leukemia and adenocarcinoma/carcinoma. Rapid systemic deamination of gemcitabine accounts for a brief plasma half-life but its sustained administration is often curtailed by sequelae and chemotherapeutic-resistance. A molecular strategy that diminishes these limitations is the molecular design and synthetic production of covalent gemcitabine immunochemotherapeutics that possess properties of selective “targeted” delivery. The simultaneous dual selective “targeted” delivery of gemcitabine at two separate sites on the external surface membrane of a single cancer cell types represents a therapeutic approach that can increase cytosol chemotherapeutic deposition; prolong chemotherapeutic plasma half-life (reduces administration frequency); minimize innocent exposure of normal tissues and healthy organ systems; and ultimately enhance more rapid and thorough resolution of neoplastic cell populations. Materials and Methods: A light-reactive gemcitabine intermediate synthesized utilizing succinimidyl 4,4-azipentanoate was covalently bound to anti-EGFR or anti-HER2/neu IgG by exposure to UV light (354-nm) resulting in the synthesis of covalent immunochemotherapeutics, gemcitabine-(C4-amide)-[anti-EGFR] and gemcitabine-(C4-amide)-[anti-HER2/neu]. Cytotoxic anti-neoplastic potency of gemcitabine-(C4-amide)-[anti-EGFR] and gemcitabine-(C4-amide)-[anti-HER2/neu] between gemcitabine-equivalent concentrations of 10−12 M and 10−6 M was determined utilizing chemotherapeutic-resistant mammary adenocarcinoma (SKRr-3). The organoselenium compound, [Se]-methylselenocysteine was evaluated to determine if it complemented the anti-neoplastic potency of the covalent gemcitabine immunochemotherapeutics. Results: Gemcitabine-(C4-amide)-[anti-EGFR], gemcitabine-(C4-amide)-[anti-HER2/neu] and the dual simultaneous combination of gemcitabine-(C4-amide)-[anti-EGFR] with gemcitabine-(C4-amide)-[anti-HER2/neu] all had anti-neoplastic cytotoxic potency against mammary adenocarcinoma. Gemcitabine-(C4-amide)-[anti-EGFR] and gemcitabine-(C4-amide)-[anti-HER2/neu] produced progressive increases in anti-neoplastic cytotoxicity that were greatest between gemcitabine-equivalent concentrations of 10−9 M and 10−6 M. Dual simultaneous combinations of gemcitabine-(C4-amide)-[anti-EGFR] with gemcitabine-(C4-amide)-[anti-HER2/neu] produced levels of anti-neoplastic cytotoxicity intermediate between each of the individual covalent gemcitabine immunochemotherapeutics. Total anti-neoplastic cytotoxicity of the dual simultaneous combination of gemcitabine-(C4-amide)-[anti-EGFR] and gemcitabine-(C4-amide)-[anti-HER2/neu] against chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) was substantially higher when formulated with [Se]-methylsele-nocysteine. PMID:25821636

Vorinostat Combined with High-Dose Gemcitabine, Busulfan, and Melphalan with Autologous Stem Cell Transplantation in Patients with Refractory Lymphomas.

PubMed

Nieto, Yago; Valdez, Benigno C; Thall, Peter F; Ahmed, Sairah; Jones, Roy B; Hosing, Chitra; Popat, Uday; Shpall, Elizabeth J; Qazilbash, Muzaffar; Gulbis, Alison; Anderlini, Paolo; Alousi, Amin; Shah, Nina; Bashir, Qaiser; Liu, Yan; Oki, Yasuhiro; Hagemeister, Frederick; Fanale, Michelle; Dabaja, Bouthaina; Pinnix, Chelsea; Champlin, Richard; Andersson, Borje S

2015-11-01

More active high-dose regimens are needed for refractory/poor-risk relapsed lymphomas. We previously developed a regimen of infusional gemcitabine/busulfan/melphalan, exploiting the synergistic interaction. Its encouraging activity in refractory lymphomas led us to further enhance its use as a platform for epigenetic modulation. We previously observed increased cytotoxicity in refractory lymphoma cell lines when the histone deacetylase inhibitor vorinostat was added to gemcitabine/busulfan/melphalan, which prompted us to clinically study this four-drug combination. Patients ages 12 to 65 with refractory diffuse large B cell lymphoma (DLCL), Hodgkin (HL), or T lymphoma were eligible. Vorinostat was given at 200 mg/day to 1000 mg/day (days -8 to -3). Gemcitabine was infused continuously at 10 mg/m(2)/minute over 4.5 hours (days -8 and -3). Busulfan dosing targeted 4000 μM-minute/day (days -8 to -5). Melphalan was infused at 60 mg/m(2)/day (days -3 and -2). Patients with CD20(+) tumors received rituximab (375 mg/m(2), days +1 and +8). We enrolled 78 patients: 52 DLCL, 20 HL, and 6 T lymphoma; median age 44 years (range, 15 to 65); median 3 prior chemotherapy lines (range, 2 to 7); and 48% of patients had positron emission tomography-positive tumors at high-dose chemotherapy (29% unresponsive). The vorinostat dose was safely escalated up to 1000 mg/day, with no treatment-related deaths. Toxicities included mucositis and dermatitis. Neutrophils and platelets engrafted promptly. At median follow-up of 25 (range, 16 to 41) months, event-free and overall survival were 61.5% and 73%, respectively (DLCL) and 45% and 80%, respectively (HL). In conclusion, vorinostat/gemcitabine/busulfan/melphalan is safe and highly active in refractory/poor-risk relapsed lymphomas, warranting further evaluation. This trial was registered at ClinicalTrials.gov (NCI-2011-02891). Copyright © 2015 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

Intercellular diffusion of a fluorescent sucrose analog via the septal junctions in a filamentous cyanobacterium.

PubMed

Nürnberg, Dennis J; Mariscal, Vicente; Bornikoel, Jan; Nieves-Morión, Mercedes; Krauß, Norbert; Herrero, Antonia; Maldener, Iris; Flores, Enrique; Mullineaux, Conrad W

2015-03-17

Many filamentous cyanobacteria produce specialized nitrogen-fixing cells called heterocysts, which are located at semiregular intervals along the filament with about 10 to 20 photosynthetic vegetative cells in between. Nitrogen fixation in these complex multicellular bacteria depends on metabolite exchange between the two cell types, with the heterocysts supplying combined-nitrogen compounds but dependent on the vegetative cells for photosynthetically produced carbon compounds. Here, we used a fluorescent tracer to probe intercellular metabolite exchange in the filamentous heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120. We show that esculin, a fluorescent sucrose analog, is incorporated by a sucrose import system into the cytoplasm of Anabaena cells. The cytoplasmic esculin is rapidly and reversibly exchanged across vegetative-vegetative and vegetative-heterocyst cell junctions. Our measurements reveal the kinetics of esculin exchange and also show that intercellular metabolic communication is lost in a significant fraction of older heterocysts. SepJ, FraC, and FraD are proteins located at the intercellular septa and are suggested to form structures analogous to gap junctions. We show that a ΔsepJ ΔfraC ΔfraD triple mutant shows an altered septum structure with thinner septa but a denser peptidoglycan layer. Intercellular diffusion of esculin and fluorescein derivatives is impaired in this mutant, which also shows a greatly reduced frequency of nanopores in the intercellular septal cross walls. These findings suggest that FraC, FraD, and SepJ are important for the formation of junctional structures that constitute the major pathway for feeding heterocysts with sucrose. Anabaena and its relatives are filamentous cyanobacteria that exhibit a sophisticated form of prokaryotic multicellularity, with the formation of differentiated cell types, including normal photosynthetic cells and specialized nitrogen-fixing cells called heterocysts. The question of how heterocysts communicate and exchange metabolites with other cells in the filament is key to understanding this form of bacterial multicellularity. Here we provide the first information on the intercellular exchange of a physiologically important molecule, sucrose. We show that a fluorescent sucrose analog can be imported into the Anabaena cytoplasm by a sucrose import system. Once in the cytoplasm, it is rapidly and reversibly exchanged among all of the cells in the filament by diffusion across the septal junctions. Photosynthetically produced sucrose likely follows the same route from cytoplasm to cytoplasm. We identify some of the septal proteins involved in sucrose exchange, and our results indicate that these proteins form structures functionally analogous to metazoan gap junctions. Copyright © 2015 Nürnberg et al.

Targeting the Warburg effect with a novel glucose transporter inhibitor to overcome gemcitabine resistance in pancreatic cancer cells

PubMed Central

Lai, I-Lu; Chou, Chih-Chien; Lai, Po-Ting; Fang, Chun-Sheng; Shirley, Lawrence A.; Yan, Ribai; Mo, Xiaokui; Bloomston, Mark; Kulp, Samuel K.; Bekaii-Saab, Tanios; Chen, Ching-Shih

2014-01-01

Gemcitabine resistance remains a significant clinical challenge. Here, we used a novel glucose transporter (Glut) inhibitor, CG-5, as a proof-of-concept compound to investigate the therapeutic utility of targeting the Warburg effect to overcome gemcitabine resistance in pancreatic cancer. The effects of gemcitabine and/or CG-5 on viability, survival, glucose uptake and DNA damage were evaluated in gemcitabine-sensitive and gemcitabine-resistant pancreatic cancer cell lines. Mechanistic studies were conducted to determine the molecular basis of gemcitabine resistance and the mechanism of CG-5-induced sensitization to gemcitabine. The effects of CG-5 on gemcitabine sensitivity were investigated in a xenograft tumor model of gemcitabine-resistant pancreatic cancer. In contrast to gemcitabine-sensitive pancreatic cancer cells, the resistant Panc-1 and Panc-1GemR cells responded to gemcitabine by increasing the expression of ribonucleotide reductase M2 catalytic subunit (RRM2) through E2F1-mediated transcriptional activation. Acting as a pan-Glut inhibitor, CG-5 abrogated this gemcitabine-induced upregulation of RRM2 through decreased E2F1 expression, thereby enhancing gemcitabine-induced DNA damage and inhibition of cell survival. This CG-5-induced inhibition of E2F1 expression was mediated by the induction of a previously unreported E2F1-targeted microRNA, miR-520f. The addition of oral CG-5 to gemcitabine therapy caused greater suppression of Panc-1GemR xenograft tumor growth in vivo than either drug alone. Glut inhibition may be an effective strategy to enhance gemcitabine activity for the treatment of pancreatic cancer. PMID:24879635

Development and evaluation of adsorption sheet (HD safe sheet-U) using active carbon for the purpose of the preventing the contamination diffusion of urinary excreted anticancer drug.

PubMed

Sato, Junya; Ohkubo, Haruka; Sasaki, Yuki; Yokoi, Makoto; Hotta, Yasunori; Kudo, Kenzo

2017-01-01

Certain amount of anticancer drugs is excreted in the urine of patients receiving anticancer drugs, and urinary scattering including anticancer drugs at excretion has become a route of anticancer drug contamination. Therefore, we developed an active carbon sheet (HD safe sheet-U) that prevented diffusion by adsorbing anticancer drugs including that excreted in urine. The present study conducted a performance evaluation of this sheet. The adsorption performance of active carbon to anticancer drug in the urine was evaluated by determining concentration changes in the active carbon suspension (5 mg/mL) of 14 kinds of anticancer drugs (cyclophosphamide, ifosfamide, carboplatin, cisplatin, methotrexate, 5-fluorouracil, cytarabine, gemcitabine, doxorubicin, epirubicin, paclitaxel, docetaxel, etoposide, and irinotecan) diluted with artificial urine. Adhesion of the anticancer drug dropping on the sheet to a slipper sole was evaluated because urine including anticancer drugs is scattered on the floor, which can spread by adhering to shoe soles of patients and healthcare workers. The performance of the active carbon sheet was compared with two other types of medical adsorption sheets used as control sheets. Anticancer drugs diluted with artificial urine (1 mL) were dropped on the active carbon sheet and the two control sheets. The sheets were trod with slippers made by polyvinyl chloride. The adhered anticancer drug was wiped off and its quantity was determined. A remarkable decrease in anticancer drug concentrations, except for cisplatin, was detected by mixture of active carbon in the artificial urine (0-79.6%). The quantity of anticancer drug adhesion to slipper soles from the active carbon sheet was significantly lower compared with that observed for the two control sheets for eight kinds of anticancer drugs (cyclophosphamide, ifosfamide, carboplatin, methotrexate, cytarabine, gemcitabine, doxorubicin, and docetaxel). There was no adhesion in cyclophosphamide and docetaxel. Furthermore, the quantities of adhesion in cytarabine, gemcitabine, doxorubicin, paclitaxel, and irinotecan were lower than determination limit. Active carbon might be effective in adsorbing urinary anticancer drugs. The active carbon sheet adsorbed urinary excreted anticancer drugs, and use of such sheets might prevent diffusion of contamination due to urinary excreted anticancer drugs.

A novel HDAC inhibitor, CG200745, inhibits pancreatic cancer cell growth and overcomes gemcitabine resistance.

PubMed

Lee, Hee Seung; Park, Soo Been; Kim, Sun A; Kwon, Sool Ki; Cha, Hyunju; Lee, Do Young; Ro, Seonggu; Cho, Joong Myung; Song, Si Young

2017-01-30

Pancreatic cancer is predominantly lethal, and is primarily treated using gemcitabine, with increasing resistance. Therefore, novel agents that increase tumor sensitivity to gemcitabine are needed. Histone deacetylase (HDAC) inhibitors are emerging therapeutic agents, since HDAC plays an important role in cancer initiation and progression. We evaluated the antitumor effect of a novel HDAC inhibitor, CG200745, combined with gemcitabine/erlotinib on pancreatic cancer cells and gemcitabine-resistant pancreatic cancer cells. Three pancreatic cancer-cell lines were used to evaluate the antitumor effect of CG200745 combined with gemcitabine/erlotinib. CG200745 induced the expression of apoptotic proteins (PARP and caspase-3) and increased the levels of acetylated histone H3. CG200745 with gemcitabine/erlotinib showed significant growth inhibition and synergistic antitumor effects in vitro. In vivo, gemcitabine/erlotinib and CG200745 reduced tumor size up to 50%. CG200745 enhanced the sensitivity of gemcitabine-resistant pancreatic cancer cells to gemcitabine, and decreased the level of ATP-binding cassette-transporter genes, especially multidrug resistance protein 3 (MRP3) and MRP4. The novel HDAC inhibitor, CG200745, with gemcitabine/erlotinib had a synergistic anti-tumor effect on pancreatic cancer cells. CG200745 significantly improved pancreatic cancer sensitivity to gemcitabine, with a prominent antitumor effect on gemcitabine-resistant pancreatic cancer cells. Therefore, improved clinical outcome is expected in the future.

A novel HDAC inhibitor, CG200745, inhibits pancreatic cancer cell growth and overcomes gemcitabine resistance

PubMed Central

Lee, Hee Seung; Park, Soo Been; Kim, Sun A; Kwon, Sool Ki; Cha, Hyunju; Lee, Do Young; Ro, Seonggu; Cho, Joong Myung; Song, Si Young

2017-01-01

Pancreatic cancer is predominantly lethal, and is primarily treated using gemcitabine, with increasing resistance. Therefore, novel agents that increase tumor sensitivity to gemcitabine are needed. Histone deacetylase (HDAC) inhibitors are emerging therapeutic agents, since HDAC plays an important role in cancer initiation and progression. We evaluated the antitumor effect of a novel HDAC inhibitor, CG200745, combined with gemcitabine/erlotinib on pancreatic cancer cells and gemcitabine-resistant pancreatic cancer cells. Three pancreatic cancer-cell lines were used to evaluate the antitumor effect of CG200745 combined with gemcitabine/erlotinib. CG200745 induced the expression of apoptotic proteins (PARP and caspase-3) and increased the levels of acetylated histone H3. CG200745 with gemcitabine/erlotinib showed significant growth inhibition and synergistic antitumor effects in vitro. In vivo, gemcitabine/erlotinib and CG200745 reduced tumor size up to 50%. CG200745 enhanced the sensitivity of gemcitabine-resistant pancreatic cancer cells to gemcitabine, and decreased the level of ATP-binding cassette-transporter genes, especially multidrug resistance protein 3 (MRP3) and MRP4. The novel HDAC inhibitor, CG200745, with gemcitabine/erlotinib had a synergistic anti-tumor effect on pancreatic cancer cells. CG200745 significantly improved pancreatic cancer sensitivity to gemcitabine, with a prominent antitumor effect on gemcitabine-resistant pancreatic cancer cells. Therefore, improved clinical outcome is expected in the future. PMID:28134290

Gemcitabine-induced rectus abdominus radiation recall.

PubMed

Fakih, Marwan G

2006-05-09

Radiation recall has been described in the context of gemcitabine chemotherapy. However, this phenomenon has been largely limited to skin. We hereby report a case of radiation recall dermatitis and myositis occurring on gemcitabine monotherapy, five months after completing chemoradiation for locally advanced pancreatic cancer. Radiation recall resolved spontaneously with withdrawal of gemcitabine. This is the second case report that describes gemcitabine-induced radiation recall in rectus abdominus muscles after gemcitabine-based radiation therapy. Given the wide use of gemcitabine following chemoradiation for pancreatic cancer, providers should be aware of this potential complication.

Ku70 inhibits gemcitabine-induced DNA damage and pancreatic cancer cell apoptosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, Jiali; Hui, Pingping; Meng, Wenying

The current study focused on the role of Ku70, a DNA-dependent protein kinase (DNA-PK) complex protein, in pancreatic cancer cell resistance to gemcitabine. In both established cell lines (Mia-PaCa-2 and PANC-1) and primary human pancreatic cancer cells, shRNA/siRNA-mediated knockdown of Ku70 significantly sensitized gemcitabine-induced cell death and proliferation inhibition. Meanwhile, gemcitabine-induced DNA damage and subsequent pancreatic cancer cell apoptosis were also potentiated with Ku70 knockdown. On the other hand, exogenous overexpression of Ku70 in Mia-PaCa-2 cells suppressed gemcitabine-induced DNA damage and subsequent cell apoptosis. In a severe combined immune deficient (SCID) mice Mia-PaCa-2 xenograft model, gemcitabine-induced anti-tumor activity was remarkably pontificatedmore » when combined with Ku70 shRNA knockdown in the xenografts. The results of this preclinical study imply that Ku70 might be a primary resistance factor of gemcitabine, and Ku70 silence could significantly chemo-sensitize gemcitabine in pancreatic cancer cells. - Highlights: • Ku70 knockdown sensitizes gemcitabine-induced killing of pancreatic cancer cells. • Ku70 knockdown facilitates gemcitabine-induced DNA damage and cell apoptosis. • Ku70 overexpression deceases gemcitabine's sensitivity in pancreatic cancer cells. • Ku70 knockdown sensitizes gemcitabine-induced anti-tumor activity in vivo.« less

Ratio of phosphorylated HSP27 to nonphosphorylated HSP27 biphasically acts as a determinant of cellular fate in gemcitabine-resistant pancreatic cancer cells.

PubMed

Kang, Dongxu; Choi, Hye Jin; Kang, Sujin; Kim, So Young; Hwang, Yong-Sic; Je, Suyeon; Han, Zhezhu; Kim, Joo-Hang; Song, Jae J

2015-04-01

Gemcitabine has been used most commonly as an anticancer drug to treat advanced pancreatic cancer patients. However, intrinsic or acquired resistance of pancreatic cancer to gemcitabine was also developed, which leads to very low five-year survival rates. Here, we investigated whether cellular levels of HSP27 phosphorylation act as a determinant of cellular fate with gemcitabine. In addition we have demonstrated whether HSP27 downregulation effectively could overcome the acquisition of gemcitabine resistance by using transcriptomic analysis. We observed that gemcitabine induced p38/HSP27 phosphorylation and caused acquired resistance. After acquisition of gemcitabine resistance, cancer cells showed higher activity of NF-κB. NF-κB activity, as well as colony formation in gemcitabine-resistant pancreatic cancer cells, was significantly decreased by HSP27 downregulation and subsequent TRAIL treatment, showing that HSP27 was a common network mediator of gemcitabine/TRAIL-induced cell death. After transcriptomic analysis, gene fluctuation after HSP27 downregulation was very similar to that of pancreatic cancer cells susceptible to gemcitabine, and then in opposite position to that of acquired gemcitabine resistance, which makes it possible to downregulate HSP27 to overcome the acquired gemcitabine resistance to function as an overall survival network inhibitor. Most importantly, we demonstrated that the ratio of phosphorylated HSP27 to nonphosphorylated HSP27 rather than the cellular level of HSP27 itself acts biphasically as a determinant of cellular fate in gemcitabine-resistant pancreatic cancer cells. Copyright © 2015 Elsevier Inc. All rights reserved.

Gemcitabine-induced gouty arthritis attacks.

PubMed

Bottiglieri, Sal; Tierson, Neil; Patel, Raina; Mo, Jae-Hyun; Mehdi, Syed

2013-09-01

In this case report, we review the experience of a patient who presented with early stage pancreatic cancer (Stage IIb) who underwent a Whipple procedure and adjuvant chemoradiation. The patient's past medical history included early stage colon cancer in remission, post-traumatic-stress-disorder, hypertension, hyperlipidemia, osteoarthritis, gout, and pre-diabetes. Chemotherapy initially consisted of weekly gemcitabine. The patient developed acute gouty attacks after his second dose of gemcitabine, which brought him to the emergency room for emergent treatment on several occasions. Gemcitabine was held and treatment began with fluorouracil and concurrent radiation. After completion of his chemoradiation with fluorouracil, he was again treated with weekly gemcitabine alone. As soon as the patient started gemcitabine chemotherapy the patient developed gouty arthritis again, requiring discontinuation of chemotherapy. The patient received no additional treatment until his recent recurrence 8 months later where gemcitabine chemotherapy was again introduced with prophylactic medications consisting of allopurinol 100 mg by mouth daily and colchicine 0.6 mg by mouth daily throughout gemcitabine chemotherapy, and no signs of gouty arthritis occurred. To our knowledge, this is the first case report describing gout attacks associated with gemcitabine therapy. There is limited data available describing the mechanism that gouty arthritis may be precipitated from gemcitabine chemotherapy. Further monitoring and management may be required in patients receiving gemcitabine chemotherapy with underlying gout.

Drosophila melanogaster deoxyribonucleoside kinase activates gemcitabine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knecht, Wolfgang; Mikkelsen, Nils Egil; Clausen, Anders Ranegaard

2009-05-01

Drosophila melanogaster multisubstrate deoxyribonucleoside kinase (Dm-dNK) can additionally sensitize human cancer cell lines towards the anti-cancer drug gemcitabine. We show that this property is based on the Dm-dNK ability to efficiently phosphorylate gemcitabine. The 2.2 A resolution structure of Dm-dNK in complex with gemcitabine shows that the residues Tyr70 and Arg105 play a crucial role in the firm positioning of gemcitabine by extra interactions made by the fluoride atoms. This explains why gemcitabine is a good substrate for Dm-dNK.

Curcumin and its cyclohexanone analogue inhibited human Equilibrative nucleoside transporter 1 (ENT1) in pancreatic cancer cells.

PubMed

Revalde, Jezrael L; Li, Yan; Wijeratne, Tharaka S; Bugde, Piyush; Hawkins, Bill C; Rosengren, Rhonda J; Paxton, James W

2017-05-15

Our group investigated combining the phytochemical curcumin and gemcitabine in a liposome, to improve gemcitabine's activity against pancreatic tumours. While optimising the curcumin: gemcitabine ratio for co-encapsulation, we found that increasing curcumin concentrations relative to gemcitabine resulted in antagonistic interactions. As curcumin is a promiscuous transporter inhibitor; we suspected that increased resistance occurred via inhibition of Equilibrative nucleoside transporter 1 (ENT1)-mediated gemcitabine uptake. To test our hypothesis, we determined whether curcumin and a related analogue, 2,6-bis((3-methoxy-4-hydroxyphenyl)methylene)-cyclohexanone (or A13), inhibited ENT1-mediated accumulation of [ 3 H]uridine and [ 3 H]gemcitabine into pancreatic cancer cells. We then confirmed the inhibition of gemcitabine accumulation by investigating whether curcumin/A13 could increase gemcitabine resistance in growth inhibition assays. We found that curcumin and A13 concentration-dependently inhibited the ENT1-mediated accumulation of both uridine and gemcitabine in MIA PaCa-2 and PANC-1 cells. We also found that non-toxic concentrations of curcumin and A13 significantly increased the resistance of both cell lines to gemcitabine. Increased resistance only occurred when curcumin/A13 was co-incubated with gemcitabine, and not with sequential exposure (i.e., curcumin first, followed by gemcitabine, or vice versa). We also found that the curcumin analogue (3E,5E)-3,5-bis[(2-fluorophenyl)methylene]-4-piperidinone (or EF24) did not inhibit gemcitabine accumulation, making it more suitable in combinations than curcumin/A13. From these results, we concluded that curcumin and A13 are inhibitors of the ENT1 transporter, but only at high concentrations (2-20µM). Curcumin is unlikely to inhibit gemcitabine uptake in tumours but may interfere with the oral absorption of ENT1 substrates due to high gut concentrations readily achievable from over-the-counter tablets/capsules. Copyright © 2017 Elsevier B.V. All rights reserved.

Gemcitabine-oxaliplatin plus rituximab (R-GemOx) as first-line treatment in elderly patients with diffuse large B-cell lymphoma: a single-arm, open-label, phase 2 trial.

PubMed

Shen, Qiu-Dan; Zhu, Hua-Yuan; Wang, Li; Fan, Lei; Liang, Jin-Hua; Cao, Lei; Wu, Wei; Xia, Yi; Li, Jian-Yong; Xu, Wei

2018-06-01

The combination of rituximab, gemcitabine, and oxaliplatin (R-GemOx) has shown high efficacy with a low toxicity profile in elderly patients with relapsed and refractory diffuse large B-cell lymphoma. We aimed to evaluate the efficacy, safety, and feasibility of the R-GemOx regimen as a first-line treatment in elderly patients with diffuse large B-cell lymphoma. In this single-arm, open-label, phase 2 clinical trial, we enrolled patients with previously untreated, histologically confirmed, CD20-positive diffuse large B-cell lymphoma, aged 70 years or older, or aged 60-69 years with an Eastern Cooperative Oncology Group (ECOG) performance status score of 2 or greater. Patients were recruited from Jiangsu Province Hospital (Jiangsu Sheng, China). The R-GemOx regimen was administered intravenously: rituximab 375 mg/m 2 on day 0; gemcitabine 1 g/m 2 on day 1; and oxaliplatin 100 mg/m 2 on day 1. The cycle was repeated every 14 days. Six cycles were planned if the patient achieved at least partial remission after the interim assessment. The primary endpoint was the proportion of patients who achieved an overall response at the end of treatment (defined as complete response plus partial response). Analyses were done by intention to treat. The trial is ongoing but no longer recruiting patients. This study is registered with ClinicalTrials.gov, number NCT01670370. Between Aug 22, 2012, and Dec 31, 2015, 60 patients were enrolled and included in the study. The median age of the patients was 75 years (IQR 70-80) and 27 (45%) patients had a poor performance status with an ECOG score of 2 or greater. 45 (75%) patients achieved an overall response at the end of the treatment, with 28 (47%) achieving a complete response. Common grade 3-4 adverse events were haematological toxicities (thrombocytopenia in five [8%] patients, anaemia in four [7%], and neutropenia in nine [15%]) and gastrointestinal complications (nausea in five [8%] patients, vomiting in three [5%], and diarrhoea in one [2%]). No treatment-related deaths were reported. The R-GemOx regimen shows high efficacy and safety as a front-line treatment in an elderly patient subpopulation and might be a therapeutic option for management of diffuse large B-cell lymphoma in elderly patients. National Natural Science Foundation of China, Jiangsu Province's Medical Elite Programme, Project of National Key Clinical Specialty, National Science & Technology Pillar Program, Jiangsu Provincial Special Program of Medical, and National Science and Technology Major Project. Copyright © 2018 Elsevier Ltd. All rights reserved.

Gemcitabine-induced CXCL8 expression counteracts its actions by inducing tumor neovascularization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Song, Yao; Baba, Tomohisa; Li, Ying-Yi

Patients with pancreatic ductal adenocarcinoma (PDAC) are frequently complicated with metastatic disease or locally advanced tumors, and consequently need chemotherapy. Gemcitabine is commonly used for PDAC treatment, but with limited efficacy. The capacity of gemcitabine to generate reactive oxygen species (ROS) in human pancreatic cancer cells, prompted us to examine its effects on the expression of pro-inflammatory cytokines and chemokines. We observed that gemcitabine enhanced selectively the expression of CXCL8 in human pancreatic cancer cells through ROS generation and NF-κB activation. In vitro blocking of CXCL8 failed to modulate gemcitabine-mediated inhibition of cell proliferation in human pancreatic cancer cells. Gemcitabine alsomore » enhanced CXCL8 expression in pancreatic cancer cells in xenografted tumor tissues. Moreover, anti-CXCL8 antibody treatment in vivo attenuated tumor formation as well as intra-tumoral vascularity in nude mice, which were transplanted with Miapaca-2 cells and treated with gemcitabine. Thus, gemcitabine-induced CXCL8 may counteract the drug through inducing neovascularization. - Highlights: • Gemcitabine induced CXCL8 expression in human pancreatic cancer cells. • CXCL8 expression required ROS generation and NF-κB activation. • CXCL8 did not affect in vitro proliferation of human pancreatic cancer cells. • CXCL8 in vivo counteracted gemcitabine by inducing neovascularization.« less

Cell cycle perturbation induced by gemcitabine in human tumor cells in cell culture, xenografts and bladder cancer patients: implications for clinical trial designs combining gemcitabine with a Chk1 inhibitor.

PubMed

Montano, Ryan; Khan, Nadeem; Hou, Huagang; Seigne, John; Ernstoff, Marc S; Lewis, Lionel D; Eastman, Alan

2017-09-15

Gemcitabine irreversibly inhibits ribonucleotide reductase and induces S phase arrest but whether this occurs in tumors in mice or patients has not been established. Tumor cells in culture were incubated with gemcitabine for 6 h to approximate the administration schedule in a patient. Concentrations that induced persistent S phase arrest thereafter correlated with cell killing. Administration of gemcitabine to mice also demonstrated a persistent S phase arrest in their tumor. The minimum dose that induced almost complete S phase arrest after 24 h (40 mg/kg) was well below the maximum tolerated dose in mice. S phase arrest was also observed in tumors of bladder cancer patients receiving gemcitabine. The Chk1 inhibitor MK-8776 sensitized cells to gemcitabine with the greatest cell killing when added 18 h after gemcitabine. In mice, the administration of MK-8776 18 h after gemcitabine elicited positivity for the DNA damage marker γH2AX; this also occurred at relatively low dose (40 mg/kg) gemcitabine. Hence, in both cell culture and xenografts, MK-8776 can markedly enhance cell killing of cells reversibly arrested in S phase by gemcitabine. Some cell lines are hypersensitive to MK-8776 as monotherapy, but this was not observed in xenograft models. Effective monotherapy requires a higher dose of Chk1 inhibitor, and target inhibition over a longer time period as compared to its use in combination. These results have important implications for combining Chk1 inhibitors with gemcitabine and suggest that Chk1 inhibitors with increased bioavailability may have improved efficacy both in combination and as monotherapy.

Gemcitabine-(5'-phosphoramidate)-[anti-IGF-1R]: molecular design, synthetic organic chemistry reactions, and antineoplastic cytotoxic potency in populations of pulmonary adenocarcinoma (A549).

PubMed

Coyne, Cody P; Narayanan, Lakshmi

2017-03-01

One molecular-based approach that increases potency and reduces dose-limited sequela is the implementation of selective 'targeted' delivery strategies for conventional small molecular weight chemotherapeutic agents. Descriptions of the molecular design and organic chemistry reactions that are applicable for synthesis of covalent gemcitabine-monophosphate immunochemotherapeutics have to date not been reported. The covalent immunopharmaceutical, gemcitabine-(5'-phosphoramidate)-[anti-IGF-1R] was synthesized by reacting gemcitabine with a carbodiimide reagent to form a gemcitabine carbodiimide phosphate ester intermediate which was subsequently reacted with imidazole to create amine-reactive gemcitabine-(5'-phosphorylimidazolide) intermediate. Monoclonal anti-IGF-1R immunoglobulin was combined with gemcitabine-(5'-phosphorylimidazolide) resulting in the synthetic formation of gemcitabine-(5'-phosphoramidate)-[anti-IGF-1R]. The gemcitabine molar incorporation index for gemcitabine-(5'-phosphoramidate)-[anti-IGF-R1] was 2.67:1. Cytotoxicity Analysis - dramatic increases in antineoplastic cytotoxicity were observed at and between the gemcitabine-equivalent concentrations of 10 -9  M and 10 -7  M where lethal cancer cell death increased from 0.0% to a 93.1% maximum (100.% to 6.93% residual survival), respectively. Advantages of the organic chemistry reactions in the multistage synthesis scheme for gemcitabine-(5'-phosphoramidate)-[anti-IGF-1R] include their capacity to achieve high chemotherapeutic molar incorporation ratios; option of producing an amine-reactive chemotherapeutic intermediate that can be preserved for future synthesis applications; and non-dedicated organic chemistry reaction scheme that allows substitutions of either or both therapeutic moieties, and molecular delivery platforms. © 2016 The Authors Chemical Biology & Drug Design Published by John Wiley & Sons Ltd.

In Vitro and In Vivo Comparison of Gemcitabine and the Gemcitabine Analog 1-(2'-deoxy-2'-fluoroarabinofuranosyl) Cytosine (FAC) in Human Orthotopic and Genetically Modified Mouse Pancreatic Cancer Models.

PubMed

Russell, James; Pillarsetty, Nagavarakishore; Kramer, Robin M; Romesser, Paul B; Desai, Pooja; Haimovitz-Friedman, Adriana; Lowery, Maeve A; Humm, John L

2017-12-01

Although gemcitabine is a mainstay of pancreatic cancer therapy, it is only moderately effective, and it would be desirable to measure drug uptake in patients. 1-(2'-deoxy-2'-fluoroarabinofuranosyl) cytosine (FAC), is an analog of gemcitabine, and when labeled with F-18, it may be a potential surrogate PET tracer for the drug. [ 18 F]FAC was synthesized to a radiochemical purity of >96 %. The human tumor lines AsPC1, BxPC3, Capan-1, Panc1, and MiaPaca2 were grown orthotopically in nude mice. KPC mice that conditionally express oncogenic K-ras and p53 mutations in pancreatic tissue were also used. The intra-tumoral distributions of [ 14 C]gemcitabine and [ 18 F]FAC were mapped with autoradiography. The inter-tumor correlation between [ 14 C]gemcitabine and [ 18 F]FAC was established in the orthotopic tumors. Expression of the equilibrative and concentrative nucleoside transporters (ENT, CNT) in vitro was detected by western blotting. Drug uptake was characterized in vitro using [ 3 H]gemcitabine and the effect of transporter inhibition on gemcitabine and FAC uptake was investigated. The relative affinity of cells for gemcitabine and FAC was tested in competition assays. The cell lines differed in sensitivity to transport inhibitors and in competition studies. There was a good in vivo correlation between the total uptake of [ 18 F]FAC and [ 14 C]gemcitabine, measured across all orthotopic tumors. Using the KPC and BxPC3 models, we found that [ 14 C]gemcitabine and [ 18 F]FAC were largely co-localized. In the lines examined here, [ 18 F]FAC uptake correlates well with gemcitabine in vivo, supporting the notion that [ 18 F]FAC can serve as a PET radiotracer surrogate to determine the uptake and distribution of gemcitabine within pancreatic tumors.

In Vitro and In Vivo Comparison of Gemcitabine and the Gemcitabine Analog 1-(2′-deoxy-2′-fluoroarabinofuranosyl) Cytosine (FAC) in Human Orthotopic and Genetically Modified Mouse Pancreatic Cancer Models

PubMed Central

Russell, James; Pillarsetty, Nagavarakishore; Kramer, Robin M; Romesser, Paul B; Desai, Pooja; Haimovitz-Friedman, Adriana; Lowery, Maeve A; Humm, John L

2017-01-01

Purpose Although gemcitabine is a mainstay of pancreatic cancer therapy, it is only moderately effective, and it would be desirable to measure drug uptake in patients. 1-(2′-deoxy-2′-fluoroarabinofuranosyl) cytosine (FAC), is an analog of gemcitabine, and when labeled with F-18, it may be a potential surrogate PET tracer for the drug. Procedures [18F]FAC was synthesized to a radiochemical purity of >96 %. The human tumor lines AsPC1, BxPC3, Capan-1, Panc1, and MiaPaca2 were grown orthotopically in nude mice. KPC mice that conditionally express oncogenic K-ras and p53 mutations in pancreatic tissue were also used. The intra-tumoral distributions of [14C]gemcitabine and [18F]FAC were mapped with autoradiography. The inter-tumor correlation between [14C]gemcitabine and [18F]FAC was established in the orthotopic tumors. Expression of the equilibrative and concentrative nucleoside transporters (ENT, CNT) in vitro was detected by western blotting. Drug uptake was characterized in vitro using [3H]gemcitabine and the effect of transporter inhibition on gemcitabine and FAC uptake was investigated. The relative affinity of cells for gemcitabine and FAC was tested in competition assays. The cell lines differed in sensitivity to transport inhibitors and in competition studies. There was a good in vivo correlation between the total uptake of [18F]FAC and [14C]gemcitabine, measured across all orthotopic tumors. Using the KPC and BxPC3 models, we found that [14C]gemcitabine and [18F]FAC were largely co-localized. Conclusions In the lines examined here, [18F]FAC uptake correlates well with gemcitabine in vivo, supporting the notion that [18F]FAC can serve as a PET radiotracer surrogate to determine the uptake and distribution of gemcitabine within pancreatic tumors. PMID:28349292

Antitumor Activities of Rauwolfia vomitoria Extract and Potentiation of Gemcitabine Effects Against Pancreatic Cancer.

PubMed

Yu, Jun; Chen, Qi

2014-05-01

Pancreatic cancer is one of the most lethal malignancies with very limited treatment option. In the effort of enhancing the effect of the conventional chemotherapeutic drug gemcitabine against pancreatic cancer, we investigatedin vitroandin vivothe anticancer effect of a β-carboline-enriched extract from the plantRauwolfia vomitoria(Rau), either alone or in combination with gemcitabine, in preclinical pancreatic cancer models. Rau induced apoptosis in pancreatic cancer cells in a concentration-dependent manner, and completely inhibited colony formation of PANC-1 cells in soft agar. The combination of Rau and gemcitabine had synergistic effect in inhibiting cell growth with dose reduction effect for gemcitabine. In an orthotopic pancreatic cancer mouse model, PANC-1 tumor growth was significantly suppressed by Rau treatment. Metastasis was inhibited by Rau. Adding Rau to gemcitabine treatment reduced tumor burden and metastatic potential in the gemcitabine non-responsive tumor. These data suggest that Rau possesses anti-pancreatic cancer activity and could improve effect of gemcitabine. © The Author(s) 2014.

Influence of graphene-oxide nanosheets impregnation on properties of sterculia gum-polyacrylamide hydrogel formed by radiation induced polymerization.

PubMed

Singh, Baljit; Singh, Baldev

2017-06-01

Present work is an attempt, to explore the potential of graphene oxide nanoplates impregnation, on the mechanical and drug delivery properties of sterculia gum-polyacrylamide composite hydrogel formed by radiation induced polymerization. These polymers were characterized by SEM, cryo-SEM, AFM, FTIR's, 13 C NMR and swelling studies. Release profile of an anticancer drug 'gemcitabine' was studied to determine the drug release mechanism and best fit kinetic model. Furthermore, some important biomedical properties of the polymers such as blood compatibility, mucoadhesion, antioxidant properties and gel strength were also studied. Impregnation of GO into sterculia gum-poly(AAm) hydrogels decreased the swelling of hydrogels but improved the mechanical, drug loading and drug release properties of the hydrogels. Release of gemcitabine from drug loaded hydrogels occurred through non-Fickian diffusion mechanism and release profile was best fitted in first order kinetic model. These hydrogels have been found as haemocompatible, mucoadhesive, and antioxidant in nature. Copyright © 2017 Elsevier B.V. All rights reserved.

Diagnostic Microdosing Approach to Study Gemcitabine Resistance

DOE PAGES

Scharadin, Tiffany M.; Zhang, Hongyong; Zimmermann, Maike; ...

2016-09-22

Gemcitabine metabolites cause the termination of DNA replication and induction of apoptosis. In this paper, we determined whether subtherapeutic “microdoses” of gemcitabine are incorporated into DNA at levels that correlate to drug cytotoxicity. A pair of nearly isogenic bladder cancer cell lines differing in resistance to several chemotherapy drugs were treated with various concentrations of 14C-labeled gemcitabine for 4–24 h. Drug incorporation into DNA was determined by accelerator mass spectrometry. A mechanistic analysis determined that RRM2, a DNA synthesis protein and a known resistance factor, substantially mediated gemcitabine toxicity. Finally, these results support gemcitabine levels in DNA as a potentialmore » biomarker of drug cytotoxicity.« less

Diagnostic Microdosing Approach to Study Gemcitabine Resistance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scharadin, Tiffany M.; Zhang, Hongyong; Zimmermann, Maike

Gemcitabine metabolites cause the termination of DNA replication and induction of apoptosis. In this paper, we determined whether subtherapeutic “microdoses” of gemcitabine are incorporated into DNA at levels that correlate to drug cytotoxicity. A pair of nearly isogenic bladder cancer cell lines differing in resistance to several chemotherapy drugs were treated with various concentrations of 14C-labeled gemcitabine for 4–24 h. Drug incorporation into DNA was determined by accelerator mass spectrometry. A mechanistic analysis determined that RRM2, a DNA synthesis protein and a known resistance factor, substantially mediated gemcitabine toxicity. Finally, these results support gemcitabine levels in DNA as a potentialmore » biomarker of drug cytotoxicity.« less

Activator protein 1 promotes gemcitabine-induced apoptosis in pancreatic cancer by upregulating its downstream target Bim.

PubMed

Ren, Xiaoxia; Zhao, Wenjing; Du, Yongxing; Zhang, Taiping; You, Lei; Zhao, Yupei

2016-12-01

Gemcitabine is a commonly used chemotherapy drug in pancreatic cancer. The function of activator protein 1 (AP-1) is cell-specific, and its function depends on the expression of other complex members. In the present study, we added gemcitabine to the media of Panc-1 and SW1990 cells at clinically achieved concentrations (10 µM). Compared with constitutive c-Fos expression, c-Jun expression increased in a dose-dependent manner upon gemcitabine treatment. c-Jun overexpression increased gemcitabine-induced apoptosis through Bim activation, while cell apoptosis and Bim expression decreased following c-Jun knockdown. Furthermore, gemcitabine-induced apoptosis and Bim levels decreased when c-Jun phosphorylation was blocked by SP600125. Our findings suggest that c-Jun, which is a member of the AP-1 complex, functions in gemcitabine-induced apoptosis by regulating its downstream target Bim in pancreatic cancer cells.

Degradation chemistry of gemcitabine hydrochloride, a new antitumor agent.

PubMed

Anliker, S L; McClure, M S; Britton, T C; Stephan, E A; Maple, S R; Cooke, G G

1994-05-01

The anti-tumor agent gemcitabine hydrochloride, a beta-difluoronucleoside, is remarkably stable in the solid state. In 0.1 N HCI solution at 40 degrees C, deamination of gemcitabine occurs, yielding its uridine analogue. Approximately 86% of the initial gemcitabine remains after 4 weeks under these conditions. Cleavage of the N-glycosidic bond of gemcitabine or conversion to its alpha-anomer in 0.1 N HCI solution is not observed over a 4-week period. However, this work has shown that gemcitabine hydrochloride anomerizes in 0.1 N NaOH at 40 degrees C. Approximately 72% of the initial gemcitabine remains after 4 weeks under the basic conditions used. Uridine hydrolysis products are also formed under these conditions. The anormerization reaction, which is unusual under basic conditions, has been confirmed by characterization of the chromatographically isolated alpha-anomer by NMR and mass spectrometry. A mechanism involving an acyclic intermediate is proposed.

Lessons Learned from Gemcitabine: Impact of Therapeutic Carrier Systems and Gemcitabine's Drug Conjugates on Cancer Therapy.

PubMed

Dyawanapelly, Sathish; Kumar, Animesh; Chourasia, Manish K

2017-01-01

Currently, drug delivery systems have a high impact in cancer therapy and are receiving more attention than conventional cancer treatment modalities. Compared with current cancer therapies, gemcitabine (2', 2'-difluoro-2'-deoxycytidine) has been proven to be an effective chemotherapeutic agent against pancreatic, colon, bladder, breast, ovarian, non-small-cell lung, and head and neck cancers in combination with other anticancer agents. To improve the safety and efficacy of cytotoxic drugs, several drug delivery systems have been explored. This review outlines the recent work directed toward gemcitabine delivery systems for cancer therapy, including aerosols, polymeric nanoparticles, liposomes, microparticles, carbon nanotubes, and multifunctional theranostic nanomedicines. It also provides insight into the design and development of gemcitabine conjugation for safe and effective cancer therapy. Despite the clinical promises of gemcitabine, many therapeutic challenges remain. Specifically, its therapeutic use in cancer chemotherapy is impeded by a short biological half-life, caused by its rapid metabolism, and resistance due to increased expression of ribonucleotide reductase. In our opinion, many research investigations have contributed to improve the selectivity and efficacy of gemcitabine. This combined approach of drug delivery systems and gemcitabine conjugates has shown promising efficacy in preclinical models and significant potential for future clinical cancer-therapeutic applications. Also, these strategies overcome most of the aforementioned limits of gemcitabine.

A phase I human trial of mitoguazone and gemcitabine sequential bi-weekly treatment of cancer patients.

PubMed

Ishmael, D Richard; Chen, Wei R; Hamilton, Steven A; Liu, Hong; Nordquist, Robert E

2003-01-01

Our previous studies have demonstrated the existence of synergism in a combination therapy using mitoguazone and gemcitabine when the mitoguazone is administered 24 hours before gemcitabine. Based on the cell culture and animal experimental results, a phase I clinical trial was performed in order to determine the toxicity of the combined treatment. Mitoguazone and gemcitabine were administered sequentially: mitoguazone on day 1 and gemcitabine on day 2. This cycle was repeated every 2 weeks. The dosages of these two drugs were varied between patients. Ten patients were enrolled in the study. Six patients began treatment at dose level 1 (mitoguazone 500 mg/m2, gemcitabine 1500 mg/m2), three at dose level 2 (mitoguazone 500 mg/m2, gemcitabine 2000 mg/m2), and one at dose level 3 (mitoguazone 600 mg/m2, gemcitabine 2000 mg/m2). Dose-limiting toxicity (DLT) was only observed in two patients treated at dose level 1 and one patient treated at dose level 3, while all the other patients only experienced nonhematologic toxicity, such as asthenia and mucositis. Two melanoma patients showed responses (one partial and one minor) to the treatment. One lymphoma patient also showed a brief partial response. This phase I trial indicated that the combination of mitoguazone and gemcitabine had limited but noticeable activity for treatment of cancer patients. Further study on the toxicity and on the effect of the scheduled mitoguazone-gemcitabine combination is needed.

In vitro and in vivo studies of pharmacokinetics and antitumor efficacy of D07001-F4, an oral gemcitabine formulation.

PubMed

Hao, Wei-Hua; Wang, Jong-Jing; Hsueh, Shu-Ping; Hsu, Pei-Jing; Chang, Li-Chien; Hsu, Chang-Shan; Hsu, Kuang-Yang

2013-02-01

The chemotherapy agent gemcitabine is currently administered intravenously because the drug has poor oral bioavailability. In order to assess the pharmacokinetics and antitumor activity of D07001-F4, a new self-microemulsifying oral drug delivery system preparation of gemcitabine, this study was performed to compare the effect of D07001-F4 with administered gemcitabine in vitro and in vivo. D07001-F4 pharmacokinetics was examined by evaluation of in vitro deamination of D07001-F4 and gemcitabine hydrochloride by recombinant human cytidine deaminase (rhCDA) and in vivo evaluation of D07001-F4 pharmacokinetics in mice. Antitumor activity was evaluated by comparing the effect of D07001-F4 and gemcitabine hydrochloride in inhibiting growth in nine cancer cell lines and by examining the effect of D07001-F4 and gemcitabine in two xenograft tumor models in mice. In vitro deamination of D07001-F4 by rhCDA was 3.3-fold slower than deamination of gemcitabine hydrochloride. Growth inhibition by D07001-F4 of 7 of the 8 cancer cell lines was increased compared with that seen with gemcitabine hydrochloride, and D07001-F4 inhibited the growth of pancreatic and colon cancer xenografts. In vivo pharmacokinetics showed the oral bioavailability of D07001-F4 to be 34%. D07001-F4 was effective against several cancer types, was metabolized more slowly than gemcitabine hydrochloride, and exhibited enhanced oral bioavailability.

Fibroblast drug scavenging increases intratumoural gemcitabine accumulation in murine pancreas cancer

PubMed Central

Hessmann, E; Patzak, M S; Klein, L; Chen, N; Kari, V; Ramu, I; Bapiro, T E; Frese, K K; Gopinathan, A; Richards, F M; Jodrell, D I; Verbeke, C; Li, X; Heuchel, R; Löhr, J M; Johnsen, S A; Gress, T M; Ellenrieder, V; Neesse, A

2018-01-01

Objective Desmoplasia and hypovascularity are thought to impede drug delivery in pancreatic ductal adenocarcinoma (PDAC). However, stromal depletion approaches have failed to show clinical responses in patients. Here, we aimed to revisit the role of the tumour microenvironment as a physical barrier for gemcitabine delivery. Design Gemcitabine metabolites were analysed in LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx-1-Cre (KPC) murine tumours and matched liver metastases, primary tumour cell lines, cancer-associated fibroblasts (CAFs) and pancreatic stellate cells (PSCs) by liquid chromatography-mass spectrometry/mass spectrometry. Functional and preclinical experiments, as well as expression analysis of stromal markers and gemcitabine metabolism pathways were performed in murine and human specimen to investigate the preclinical implications and the mechanism of gemcitabine accumulation. Results Gemcitabine accumulation was significantly enhanced in fibroblast-rich tumours compared with liver metastases and normal liver. In vitro, significantly increased concentrations of activated 2′,2′-difluorodeoxycytidine-5′-triphosphate (dFdCTP) and greatly reduced amounts of the inactive gemcitabine metabolite 2′,2′-difluorodeoxyuridine were detected in PSCs and CAFs. Mechanistically, key metabolic enzymes involved in gemcitabine inactivation such as hydrolytic cytosolic 5′-nucleotidases (Nt5c1A, Nt5c3) were expressed at low levels in CAFs in vitro and in vivo, and recombinant expression of Nt5c1A resulted in decreased intracellular dFdCTP concentrations in vitro. Moreover, gemcitabine treatment in KPC mice reduced the number of liver metastases by >50%. Conclusions Our findings suggest that fibroblast drug scavenging may contribute to the clinical failure of gemcitabine in desmoplastic PDAC. Metabolic targeting of CAFs may thus be a promising strategy to enhance the antiproliferative effects of gemcitabine. PMID:28077438

Mocetinostat combined with gemcitabine for the treatment of leiomyosarcoma: Preclinical correlates

PubMed Central

Braggio, Danielle; Zewdu, Abeba; Casadei, Lucia; Batte, Kara; Bid, Hemant Kumar; Koller, David; Yu, Peter; Iwenofu, Obiajulu Hans; Strohecker, Anne; Choy, Edwin; Lev, Dina; Pollock, Raphael

2017-01-01

Leiomyosarcoma (LMS) is a malignant soft tissue sarcoma (STS) with a dismal prognosis following metastatic disease. Chemotherapeutic intervention has demonstrated to have modest clinical efficacy with no curative potential in LMS patients. Previously, we demonstrated pan-HDAC inhibition to have a superior effect in various complex karyotypic sarcomas. In this study, our goal is to evaluate the therapeutic efficacy of mocetinostat alone and in combination with gemcitabine in LMS. Human leiomyosarcoma (LMS) cell lines were used for in vitro and in vivo studies. Compounds tested included the class I HDAC inhibitor, mocetinostat, and nucleoside analog, gemcitabine. MTS and clonogenic assays were used to evaluate the effect of mocetinostat on LMS cell growth. Cleaved caspase 3/7 analysis was used to determine the effects of mocetinostat on apoptosis. Compusyn software was used to determine in vitro synergy studies for the combination of mocetinostat plus gemcitabine. A LMS xenograft model in SCID mice was used to test the impact of mocetinostat alone, gemcitabine alone and the combination of mocetinostat plus gemcitabine. Mocetinostat abrogated LMS cell growth and clonogenic potential, and enhanced apoptosis in LMS cell lines. The combination of mocetinostat plus gemcitabine exhibited a synergistic effect in LMS cells in vitro. Similarly, mocetinostat combined with gemcitabine resulted in superior anti-LMS effects in vivo. Mocetinostat reduced the expression of gemcitabine-resistance markers RRM1, RRM2, and increased the expression of gemcitabine-sensitivity marker, hENT1, in LMS cells. LMS are aggressive, metastatic tumors with poor prognosis where effective therapeutic interventions are wanting. Our studies demonstrate the potential utility of mocetinostat combined with gemcitabine for the treatment of LMS. PMID:29186204

RP101 improves the efficacy of chemotherapy in pancreas carcinoma cell lines and pancreatic cancer patients.

PubMed

Fahrig, Rudolf; Quietzsch, Detlef; Heinrich, Jörg-Christian; Heinemann, Volker; Boeck, Stefan; Schmid, Roland M; Praha, Christian; Liebert, Andreas; Sonntag, Denise; Krupitza, Georg; Hänel, Mathias

2006-10-01

RP101 [(E)-5-(2-bromovinyl)-2'-deoxyuridine (BVDU)], which supports apoptosis and prevents the acquisition of chemoresistance, was tested in cultured human pancreatic tumor cells. RP101 downregulated uridine phosphorylase, a marker of poor prognosis, and APEX1, which is involved in DNA repair, and repressed Stat3 and its target vascular endothelial growth factor. Furthermore, RP101 activated antitumor immunity as demonstrated by enhanced cytolytic activity of NK-92 natural killer cells. This was concomitant with an enhanced expression of lymphotoxins alpha and beta, natural killer cell transcript 4, tumor necrosis factor LIGHT/TNFSF-14, and intercellular adhesion molecule-1 in pancreas carcinoma cells. These results encouraged us to investigate the effect of RP101 in pancreas cancer patients. Here, we present data from two RP101 combination therapy schemes. In a first pilot study, 13 patients in stage III and VI of the disease were treated with gemcitabine +cisplatin+RP101. RP101 co-treatment enhanced remissions, survival and time to progression. Seventy-seven percent of the patients lived or have lived longer than 1 year, and 23% have lived more than 2 years. Median survival was 447 days, time to progression 280 days and the response rate 33%. A second study with 21 patients in similar stages of disease, treated with RP101+gemcitabine alone, confirmed the results of the pilot study. Eighty-three percent of the presently evaluable patients live or lived 0.5 years or longer and 33% 1 year or longer. Considering both studies, the tumor control was 94%. The data indicate that acquisition of chemoresistance was prevented and the antitumor efficacy of standard chemotherapy was improved. To our knowledge, RP101 co-treatment is more efficient than any other regimen published.

Polymeric nanoparticulate system augmented the anticancer therapeutic efficacy of gemcitabine.

PubMed

Arias, José L; Reddy, L Harivardhan; Couvreur, Patrick

2009-09-01

Gemcitabine hydrochloride is an anticancer nucleoside analogue indicated in clinic for the treatment of various solid tumors. Although this drug has been demonstrated to display anticancer activity against a wide variety of tumors, it is needed to be administered at high doses to elicit the required therapeutic response, simultaneously leading to severe adverse effects. We hypothesized that the efficient delivery of gemcitabine to tumors using a biodegradable carrier system could reduce the dose required to elicit sufficient therapeutic response. Thus, we have developed a nanoparticle formulation of gemcitabine suitable for parenteral administration based on the biodegradable polymer poly(octylcyanoacrylate) (POCA). The nanoparticles were synthesized by anionic polymerization of the corresponding monomer. Two drug loading methods were analyzed: the first one based on gemcitabine surface adsorption onto the preformed nanoparticles, and the second method being gemcitabine addition before the polymerization process leading to drug entrapment in the polymeric network. A detailed investigation of the capabilities of the polymer particles to load this drug is described. Gemcitabine entrapment into the polymer matrix yielded a higher drug loading and a slower drug release profile as compared with drug adsorption procedure. The main factors determining the gemcitabine incorporation to the polymer network were the nanoparticles preparation procedure, the monomer concentration, the surfactant concentration, the pH, and the drug concentration. The release kinetic of gemcitabine was found to be controlled by the pH and the type of drug incorporation. The cytotoxicity studies performed on L1210 tumor cells revealed a similar anticancer activity of the gemcitabine-loaded POCA (GPOCA) nanoparticle as free gemcitabine. Following intravenous administration into the mice bearing L1210 wt subcutaneous tumor, the GPOCA nanoparticles displayed significantly greater anticancer activity compared to free gemcitabine; this has been additionally confirmed by histology and immunohistochemistry studies, suggesting the potential of GPOCA for the efficient treatment of cancer.

Gemcitabine: Selective cytotoxicity, induction of inflammation and effects on urothelial function

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farr, Stefanie E; Chess-Williams, Russ; McDermott,

Intravesical gemcitabine has recently been introduced for the treatment of superficial bladder cancer and has a favourable efficacy and toxicity profile in comparison to mitomycin c (MMC), the most commonly used chemotherapeutic agent. The aim of this study was to assess the cytotoxic potency of gemcitabine in comparison to MMC in urothelial cell lines derived from non-malignant (UROtsa) and malignant (RT4 and T24) tissues to assess selectivity. Cells were treated with gemcitabine or mitomycin C at concentrations up to the clinical doses for 1 or 2 h respectively (clinical duration). Treatment combined with hyperthermia was also examined. Cell viability, ROSmore » formation, urothelial function (ATP, acetylcholine and PGE2 release) and secretion of inflammatory cytokines were assessed. Gemcitabine displayed a high cytotoxic selectivity for the two malignant cell lines (RT4, T24) compared to the non-malignant urothelial cells (UROtsa, proliferative and non-proliferative). In contrast, the cytotoxic effects of MMC were non-selective with equivalent potency in each of the cell lines. The cytotoxic effect of gemcitabine in the malignant cell lines was associated with an elevation in free radical formation and was significantly decreased in the presence of an equilibrative nucleoside transporter inhibitor. Transient changes in urothelial ATP and PGE{sub 2} release were observed, with significant increase in release of interleukin-6, interleukin-8 and interleukin-1β from urothelial cells treated with gemcitabine. The selectivity of gemcitabine for malignant urothelial cells may account for the less frequent adverse urological effects with comparison to other commonly used chemotherapeutic agents. - Highlights: • Intravesical gemcitabine has recently been introduced to treat bladder cancer. • Gemcitabine is selectively toxic for malignant urothelial cells. • Urothelial ATP, PGE{sub 2} and inflammatory cytokines were altered by gemcitabine. • Selectivity of gemcitabine may account for less frequent urological side effects.« less

Randomized Phase II Trial of Gemcitabine Plus TH-302 Versus Gemcitabine in Patients With Advanced Pancreatic Cancer.

PubMed

Borad, Mitesh J; Reddy, Shantan G; Bahary, Nathan; Uronis, Hope E; Sigal, Darren; Cohn, Allen L; Schelman, William R; Stephenson, Joe; Chiorean, E Gabriela; Rosen, Peter J; Ulrich, Brian; Dragovich, Tomislav; Del Prete, Salvatore A; Rarick, Mark; Eng, Clarence; Kroll, Stew; Ryan, David P

2015-05-01

TH-302 is an investigational hypoxia-activated prodrug that releases the DNA alkylator bromo-isophosphoramide mustard in hypoxic settings. This phase II study (NCT01144455) evaluated gemcitabine plus TH-302 in patients with previously untreated, locally advanced or metastatic pancreatic cancer. Patients were randomly assigned 1:1:1 to gemcitabine (1,000 mg/m(2)), gemcitabine plus TH-302 240 mg/m(2) (G+T240), or gemcitabine plus TH-302 340 mg/m(2) (G+T340). Randomized crossover after progression on gemcitabine was allowed. The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), tumor response, CA 19-9 response, and safety. Two hundred fourteen patients (77% with metastatic disease) were enrolled between June 2010 and July 2011. PFS was significantly longer with gemcitabine plus TH-302 (pooled combination arms) compared with gemcitabine alone (median PFS, 5.6 v 3.6 months, respectively; hazard ratio, 0.61; 95% CI, 0.43 to 0.87; P = .005; median PFS for metastatic disease, 5.1 v 3.4 months, respectively). Median PFS times for G+T240 and G+T340 were 5.6 and 6.0 months, respectively. Tumor response was 12%, 17%, and 26% in the gemcitabine, G+T240, and G+T340 arms, respectively (G+T340 v gemcitabine, P = .04). CA 19-9 decrease was greater with G+T340 versus gemcitabine (-5,398 v -549 U/mL, respectively; P = .008). Median OS times for gemcitabine, G+T240, and G+T340 were 6.9, 8.7, and 9.2 months, respectively (P = not significant). The most common adverse events (AEs) were fatigue, nausea, and peripheral edema (frequencies similar across arms). Skin and mucosal toxicities (2% grade 3) and myelosuppression (55% grade 3 or 4) were the most common TH-302-related AEs but were not associated with treatment discontinuation. PFS, tumor response, and CA 19-9 response were significantly improved with G+TH-302. G+T340 is being investigated further in the phase III MAESTRO study (NCT01746979). © 2014 by American Society of Clinical Oncology.

Structural basis for the selective permeability of channels made of communicating junction proteins

PubMed Central

Ek-Vitorin, Jose F.; Burt, Janis M.

2012-01-01

The open state(s) of gap junction channels is evident from their permeation by small ions in response to an applied intercellular (transjunctional/transchannel) voltage gradient. That an open channel allows variable amounts of current to transit from cell-to-cell in the face of a constant intercellular voltage difference indicates channel open/closing can be complete or partial. The physiological significance of such open state options is, arguably, the main concern of junctional regulation. Because gap junctions are permeable to many substances, it is sensible to inquire whether and how each open state influences the intercellular diffusion of molecules as valuable as, but less readily detected than current-carrying ions. Presumably, structural changes perceived as shifts in channel conductivity would significantly alter the transjunctional diffusion of molecules whose limiting diameter approximates the pore’s limiting diameter. Moreover, changes in junctional permeability to some molecules might occur without evident changes in conductivity, either at macroscopic or single channel level. Open gap junction channels allow the exchange of cytoplasmic permeants between contacting cells by simple diffusion. The identity of such permeants, and the functional circumstances and consequences of their junctional exchange presently constitute the most urgent (and demanding) themes of the field. Here, we consider the necessity for regulating this exchange, the possible mechanism(s) and structural elements likely involved in such regulation, and how regulatory phenomena could be perceived as changes in chemical vs. electrical coupling; an overall reflection on our collective knowledge of junctional communication is then applied to suggest new avenues of research. PMID:22342665

Remodelling of cellular excitation (reaction) and intercellular coupling (diffusion) by chronic atrial fibrillation represented by a reaction-diffusion system

NASA Astrophysics Data System (ADS)

Zhang, Henggui; Garratt, Clifford J.; Kharche, Sanjay; Holden, Arun V.

2009-06-01

Human atrial tissue is an excitable system, in which myocytes are excitable elements, and cell-to-cell electrotonic interactions are via diffusive interactions of cell membrane potentials. We developed a family of excitable system models for human atrium at cellular, tissue and anatomical levels for both normal and chronic atrial fibrillation (AF) conditions. The effects of AF-induced remodelling of cell membrane ionic channels (reaction kinetics) and intercellular gap junctional coupling (diffusion) on atrial excitability, conduction of excitation waves and dynamics of re-entrant excitation waves are quantified. Both ionic channel and gap junctional coupling remodelling have rate dependent effects on atrial propagation. Membrane channel conductance remodelling allows the propagation of activity at higher rates than those sustained in normal tissue or in tissue with gap junctional remodelling alone. Membrane channel conductance remodelling is essential for the propagation of activity at rates higher than 300/min as seen in AF. Spatially heterogeneous gap junction coupling remodelling increased the risk of conduction block, an essential factor for the genesis of re-entry. In 2D and 3D anatomical models, the dynamical behaviours of re-entrant excitation waves are also altered by membrane channel modelling. This study provides insights to understand the pro-arrhythmic effects of AF-induced reaction and diffusion remodelling in atrial tissue.

Widespread Skin Necrosis Secondary to Gemcitabine Therapy.

PubMed

Zito, Patrick M; Gonzalez, Adrianna M; Fox, Joshua D; Cronin, Megan; Mackrides, Nicholas; Kirsner, Robert S; Nichols, Anna J

2018-05-01

Gemcitabine, a pyrimidine nucleoside analogue, is an oncologic agent used in the treatment of cutaneous T-cell lymphoma (CTCL). Common dermatologic reactions associated with gemcitabine include alopecia, mild skin rash, and mucositis but skin necrosis is exceptional. Herein we present an unusual case of widespread skin necrosis mimicking toxic epidermal necrolysis in a 45-year-old woman receiving gemcitabine therapy for stage IIIA cutaneous T-cell lymphoma. This is the first reported case of a TEN-like reaction subsequent to gemcitabine treatment. J Drugs Dermatol. 2018;17(5):582-585.

Phase 1 study of inotuzumab ozogamicin combined with R-GDP for the treatment of patients with relapsed/refractory CD22+ B-cell non-Hodgkin lymphoma.

PubMed

Sangha, Randeep; Davies, Andrew; Dang, Nam H; Ogura, Michinori; MacDonald, David A; Ananthakrishnan, Revathi; Paccagnella, M Luisa; Vandendries, Erik; Boni, Joseph; Goh, Yeow Tee

2017-01-01

Objective : To evaluate safety, tolerability, and preliminary activity of inotuzumab ozogamicin (InO) plus rituximab, gemcitabine, dexamethasone, and cisplatin (R-GDP) in patients with relapsed/refractory CD22+ B-cell non-Hodgkin lymphoma (NHL). Methods : Patients received InO plus R-GDP (21-day cycle; six-cycle maximum) using up-and-down dose-escalation schema for gemcitabine and cisplatin to define the highest dosage regimen(s) with acceptable toxicity (Part 1; n  = 27). Part 2 ( n  = 10) confirmed safety and tolerability; Part 3 ( n  = 18) evaluated preliminary efficacy. Results: Among 55 patients enrolled, 42% were refractory at baseline (median 2 [range, 1-6] prior therapies); 38% had diffuse large B-cell lymphoma (DLBCL). The highest dosage regimen with acceptable toxicity was InO 0.8 mg/m 2 , rituximab 375 mg/m 2 , cisplatin 50 mg/m 2 , gemcitabine 500 mg/m 2 (day 1 only) and dexamethasone 40 mg (days 1-4); this was confirmed in Part 2, in which three patients had dose-limiting toxicities (grade 4 thrombocytopenia [ n  = 2], febrile neutropenia [ n  = 2]). Most frequent treatment-related adverse events were thrombocytopenia (any grade, 85%; grade ≥3, 75%) and neutropenia (69%; 62%). Overall (objective) response rate (ORR) was 53% (11 complete, 18 partial responses); ORR was 71%, 33%, and 62% in patients with follicular lymphoma ( n  = 14), DLBCL ( n  = 21), and mantle cell lymphoma ( n  = 13), respectively. Conclusions: InO 0.8 mg/m 2 plus R-GDP was associated with manageable toxicity, although gemcitabine and cisplatin doses were lower than in the standard R-GDP regimen due to hematologic toxicity. Evidence of antitumor activity was observed; however, these exploratory data should be interpreted with caution due to the small sample size and short follow-up duration (Clinicaltrials.gov number: NCT01055496).

Inhibitory effect of geraniol in combination with gemcitabine on proliferation of BXPC-3 human pancreatic cancer cells.

PubMed

Jin, Xiaoxin; Sun, Jichun; Miao, Xiongyong; Liu, Guoli; Zhong, Dewu

2013-08-01

To investigate the inhibitory effect of geraniol alone, or in combination with gemcitabine, on the proliferation of BXPC-3 pancreatic cancer cells. BXPC-3 cells were treated under different conditions: with geraniol at 10, 20, 40, 80 and 160 µmol/l each for 24 h, 48 h or 72 h; with 20 µmol/l geraniol for 24 h or 0 h before 20 µmol/l gemcitabine for 24 h; with 20 µmol/l geraniol for 24 h, 48 h and 72 h following 20 µmol/l gemcitabine for 24 h; or with 20 µmol/l gemcitabine alone as a control. Cell proliferation was assessed and changes in cell morphology were assessed by light and fluorescence microscopy. Apoptosis was detected using flow cytometry. Geraniol inhibited BXPC-3 cell proliferation in a time- and dosa-dependent manner. Geraniol alone or combined with gemcitabine induced BXPC-3 cell apoptosis. BXPC-3 inhibition rates with combined treatment were 55.24%, 50.69%, 49.83%, 41.85% and 45.27% following treatment with 20 µmol/l geraniol for 24 h or 0 h before 20 µmol/l gemcitabine for 24 h, or 20 µmol/l geraniol for 24 h, 48 h and 72 h, following 20 µmol/l gemcitabine for 24 h, respectively. Geraniol inhibited the proliferation of BXPC-3 cells. Geraniol significantly increased the antiproliferative and apoptosis-inducing effects of gemcitabine on BXPC-3 cells. Maximum inhibition of BXPC-3 cells was achieved with geraniol treatment for 24 h before gemcitabine treatment.

Correlation of Early Recurrence With In Vitro Adenosine Triphosphate Based Chemotherapy Response Assay in Pancreas Cancer With Postoperative Gemcitabine Chemotherapy.

PubMed

Park, Joon Seong; Kim, Jae Keun; Yoon, Dong Sup

2016-11-01

Gemcitabine-based regimens represent the standard systemic first line treatment in patients after pancreatic resection. However, the clinical impact of gemcitabine varies significantly in individuals because of chemoresistance. An in vitro adenosine triphosphate based chemotherapy response assay (ATP-CRA) was designed to evaluate the sensitivity of cancer cells to various chemotherapeutic agents. This study investigated the correlation between in vitro gemcitabine sensitivity of tumor cells and early recurrence after curative resection. From January 2007 to December 2010, the ATP-CRA for gemcitabine was tested in 64 patients surgically treated for pancreas cancer at Gangnam Severance Hospital, Seoul, Korea. We analyzed the relationship between chemosensitivity and early systemic recurrence in patients with pancreas cancer to predict disease-free survival (DFS) after curative resection in pancreas cancer. The mean cell death rate (CDR) was 20.0 (±14.5) and divided into two groups according to the mean values of the CDR. Lymphovascular invasion was more frequently shown in gemcitabine resistance group without statistical significance. In univariate and multivariate analysis, advanced tumor stage and gemcitabine sensitive group (CDR ≥ 20) were identified as independent prognostic factors for DFS. Gemcitabine sensitivity measured by ATP-CRA was well correlated with in vivo drug responsibility to predict early recurrence following gemcitabine-based adjuvant chemotherapy in patients with pancreas cancer. © 2016 Wiley Periodicals, Inc.

Diels Alder-mediated release of gemcitabine from hybrid nanoparticles for enhanced pancreatic cancer therapy.

PubMed

Oluwasanmi, Adeolu; Al-Shakarchi, Wejdan; Manzur, Ayesha; Aldebasi, Mohammed H; Elsini, Rayan S; Albusair, Malek K; Haxton, Katherine J; Curtis, Anthony D M; Hoskins, Clare

2017-11-28

Hybrid nanoparticles (HNPs) have shown huge potential as drug delivery vehicles for pancreatic cancer. Currently, the first line treatment, gemcitabine, is only effective in 23.8% of patients. To improve this, a thermally activated system was developed by introducing a linker between HNPs and gemcitabine. Whereby, heat generation resulting from laser irradiation of the HNPs promoted linker breakdown resulting in prodrug liberation. In vitro evaluation in pancreatic adenocarcinoma cells, showed the prodrug was 4.3 times less cytotoxic than gemcitabine, but exhibited 11-fold improvement in cellular uptake. Heat activation of the formulation led to a 56% rise in cytotoxicity causing it to outperform gemcitabine by 26%. In vivo the formulation outperformed free gemcitabine with a 62% reduction in tumor weight in pancreatic xenografts. This HNP formulation is the first of its kind and has displayed superior anti-cancer activity as compared to the current first line drug gemcitabine after heat mediated controlled release. Copyright © 2017 Elsevier B.V. All rights reserved.

nab-paclitaxel potentiates gemcitabine activity by reducing cytidine deaminase levels in a mouse model of pancreatic cancer

PubMed Central

Cook, Natalie; Bapiro, Tashinga E.; Lolkema, Martijn P.; Jodrell, Duncan I.; Tuveson, David A.

2016-01-01

nab-paclitaxel, an albumin-stabilized paclitaxel formulation, demonstrates clinical activity when administered in combination with gemcitabine in patients with metastatic pancreatic ductal adenocarcinoma (PDA). The limited availability of patient tissue and exquisite sensitivity of xenografts to chemotherapeutics have limited our ability to address the mechanistic basis of this treatment regimen. Here, we used a mouse model of PDA to show that the co-administration of nab-paclitaxel and gemcitabine uniquely demonstrates evidence of tumor regression. Combination treatment increases intratumoral gemcitabine levels due to a marked decrease in the primary gemcitabine metabolizing enzyme, cytidine deaminase (Cda). Correspondingly, paclitaxel reduced Cda protein levels in cultured cells through reactive oxygen species-mediated degradation, resulting in the increased stabilization of gemcitabine. Our findings support the concept that suboptimal intratumoral concentrations of gemcitabine represent a crucial mechanism of therapeutic resistance in PDA and highlight the advantages of genetically engineered mouse models in preclinical therapeutic trials. PMID:22585996

Mobile microRNAs hit the target.

PubMed

Gursanscky, Nial R; Searle, Iain R; Carroll, Bernard J

2011-11-01

MicroRNAs (miRNAs) are negative regulators of gene expression in eukaryotic organisms, whereas small interfering RNAs (siRNAs) guide host-cell defence against viruses, transposons and transgenes. A key issue in plant biology is whether miRNAs act only in cells in which they are formed, or if, like siRNAs, they also function after passive diffusion or active transportation into other cells. Recent reports show that miRNAs are indeed able to move between plant cells to direct developmental programming of gene expression. In both leaf and root development, miRNAs establish intercellular gradients of gene expression that are essential for cell and tissue differentiation. Gradients in gene expression also play crucial roles in animal development, and there is strong evidence for intercellular movement of miRNAs in animals. Thus, intercellular movement of miRNAs may be crucial to animal developmental biology as well as plants. © 2011 John Wiley & Sons A/S.

Vitamins C and K3 sensitize human urothelial tumors to gemcitabine.

PubMed

Kassouf, Wassim; Highshaw, Ralph; Nelkin, Gina M; Dinney, Colin P; Kamat, Ashish M

2006-10-01

We evaluated the antitumor effects of vitamins C and K3 for human urothelial carcinoma and the potential use of the combination of vitamins C plus K3 as a sensitizing agent for conventional chemotherapy for urothelial carcinoma. The antiproliferative and apoptotic effects of vitamin C alone, vitamin K3 alone, vitamins C plus K3, gemcitabine alone and gemcitabine plus vitamins C plus K3 were assessed in vitro by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, propidium iodide staining and flow cytometry. For in vivo studies we implanted UMUC-14 tumorigenic urothelial carcinoma cells into the subcutis of nude mice. One week later we treated 10 mice each with saline (control), vitamins C plus K3, gemcitabine or gemcitabine plus vitamins C plus K3. Treatment was continued for 4 weeks, followed by necropsy. Tumor volume was measured and tumor kinetics were established. Apoptosis and proliferation were evaluated in tumor sections using immunohistochemistry and TUNEL assay. Vitamins C plus K3 induced cytostasis and caused apoptosis to a greater degree than either vitamin alone (p < 0.05). Vitamins C plus K3 also substantially augmented the effects of gemcitabine in vitro. There were 32.3% apoptosis with gemcitabine plus vitamins C plus K3, 5.3% with gemcitabine alone and 15.8% with vitamins C plus K3 alone (p < 0.05). In vivo tumor growth was substantially inhibited by gemcitabine plus vitamins C plus K3 compared with that in the control or for either agent alone. Mean tumor weight and growth rate in the gemcitabine plus vitamins C plus K3 group (237 mg and 11.3 mm3 daily) were decreased compared with those in the control (530 mg and 34.3 mm3 daily), and those for vitamins C plus K3 alone (490 mg and 25.2 mm3 daily) and gemcitabine alone (400 mg and 21.3 mm3 daily) (p < 0.05). Vitamins C and K3 have significant antiproliferative and apoptotic effects when used in combination. This combination enhances the efficacy of gemcitabine against bladder cancer in vivo.

Fibroblast drug scavenging increases intratumoural gemcitabine accumulation in murine pancreas cancer.

PubMed

Hessmann, E; Patzak, M S; Klein, L; Chen, N; Kari, V; Ramu, I; Bapiro, T E; Frese, K K; Gopinathan, A; Richards, F M; Jodrell, D I; Verbeke, C; Li, X; Heuchel, R; Löhr, J M; Johnsen, S A; Gress, T M; Ellenrieder, V; Neesse, A

2018-03-01

Desmoplasia and hypovascularity are thought to impede drug delivery in pancreatic ductal adenocarcinoma (PDAC). However, stromal depletion approaches have failed to show clinical responses in patients. Here, we aimed to revisit the role of the tumour microenvironment as a physical barrier for gemcitabine delivery. Gemcitabine metabolites were analysed in LSL-Kras G12D/+ ; LSL-Trp53 R172H/+ ; Pdx-1-Cre (KPC) murine tumours and matched liver metastases, primary tumour cell lines, cancer-associated fibroblasts (CAFs) and pancreatic stellate cells (PSCs) by liquid chromatography-mass spectrometry/mass spectrometry. Functional and preclinical experiments, as well as expression analysis of stromal markers and gemcitabine metabolism pathways were performed in murine and human specimen to investigate the preclinical implications and the mechanism of gemcitabine accumulation. Gemcitabine accumulation was significantly enhanced in fibroblast-rich tumours compared with liver metastases and normal liver. In vitro, significantly increased concentrations of activated 2',2'-difluorodeoxycytidine-5'-triphosphate (dFdCTP) and greatly reduced amounts of the inactive gemcitabine metabolite 2',2'-difluorodeoxyuridine were detected in PSCs and CAFs. Mechanistically, key metabolic enzymes involved in gemcitabine inactivation such as hydrolytic cytosolic 5'-nucleotidases (Nt5c1A, Nt5c3) were expressed at low levels in CAFs in vitro and in vivo, and recombinant expression of Nt5c1A resulted in decreased intracellular dFdCTP concentrations in vitro. Moreover, gemcitabine treatment in KPC mice reduced the number of liver metastases by >50%. Our findings suggest that fibroblast drug scavenging may contribute to the clinical failure of gemcitabine in desmoplastic PDAC. Metabolic targeting of CAFs may thus be a promising strategy to enhance the antiproliferative effects of gemcitabine. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

SL-01, an oral gemcitabine derivative, inhibited human cancer growth more potently than gemcitabine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao, Cuirong; Yue, Bin; Liu, Huiping

2012-08-01

SL-01, an oral gemcitabine derivative, was synthesized by introducing the moiety of 3-(dodecyloxycarbonyl)pyrazine-2-carbonyl at the N4-position on the cytidine ring of gemcitabine. Our goal in this study was to evaluate the efficacy of SL-01 on the growth of human cancers with gemcitabine as control. Experiments were performed on human non-small cell lung cancer NCI-H460 and colon cancer HCT-116 both in vitro and in vivo. In vitro assays, SL-01 significantly inhibited the growth of cancer cells as determined by the 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay. Further studies indicated that SL-01 induced the cancer cells to apoptosis showing chromatin condensation andmore » externalization of phosphatidylserine. In in vivo studies, we evaluated the efficacy of SL-01 in nude mice bearing human cancer xenografts. SL-01 effectively delayed the growth of NCI-H460 and HCT-116 without significant loss of body weight. Molecular analysis indicated that the high efficacy of SL-01 was associated with its ability to induce apoptosis as evidenced by increase of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining cells, activation of caspase-9, caspase-3 and cleaved poly ADP-ribose polymerase (PARP) in tumor tissues. SL-01 also increased Bax/Bcl-2 ratio in cancer cells. These biological activities of SL-01 were more potential than that of gemcitabine. Based on these in vitro and in vivo results, SL-01 is proposed as a potent oral anticancer agent that may supplant the use of gemcitabine in the clinic. -- Highlights: ► An oral gemcitabine derivative SL-01 was synthesized. ► The effects of SL-01 were evaluated and its efficacy was compared with gemcitabine. ► The biological activities of SL-01 were more potent than that of gemcitabine. ► SL-01 could replace gemcitabine for clinical use.« less

Levels of gemcitabine transport and metabolism proteins predict survival times of patients treated with gemcitabine for pancreatic adenocarcinoma.

PubMed

Maréchal, Raphaël; Bachet, Jean-Baptiste; Mackey, John R; Dalban, Cécile; Demetter, Pieter; Graham, Kathryn; Couvelard, Anne; Svrcek, Magali; Bardier-Dupas, Armelle; Hammel, Pascal; Sauvanet, Alain; Louvet, Christophe; Paye, François; Rougier, Philippe; Penna, Christophe; André, Thierry; Dumontet, Charles; Cass, Carol E; Jordheim, Lars Petter; Matera, Eva-Laure; Closset, Jean; Salmon, Isabelle; Devière, Jacques; Emile, Jean-François; Van Laethem, Jean-Luc

2012-09-01

Patients who undergo surgery for pancreatic ductal adenocarcinoma (PDAC) frequently receive adjuvant gemcitabine chemotherapy. Key determinants of gemcitabine cytotoxicity include the activities of the human equilibrative nucleoside transporter 1 (hENT1), deoxycytidine kinase (dCK), and ribonucleotide reductase subunit 1 (RRM1). We investigated whether tumor levels of these proteins were associated with efficacy of gemcitabine therapy following surgery. Sequential samples of resected PDACs were retrospectively collected from 434 patients at 5 centers; 142 patients did not receive adjuvant treatment (33%), 243 received adjuvant gemcitabine-based regimens (56%), and 49 received nongemcitabine regimens (11%). We measured protein levels of hENT1, dCK, and RRM1 by semiquantitative immunohistochemistry with tissue microarrays and investigated their relationship with patients' overall survival time. The median overall survival time of patients was 32.0 months. Among patients who did not receive adjuvant treatment, levels of hENT1, RRM1, and dCK were not associated with survival time. Among patients who received gemcitabine, high levels of hENT1 and dCK were significantly associated with longer survival time (hazard ratios of 0.34 [P < .0001] and 0.57 [P = .012], respectively). Interaction tests for gemcitabine administration and hENT1 and dCK status were statistically significant (P = .0007 and P = .016, respectively). On multivariate analysis of this population, hENT1 and dCK retained independent predictive values, and those patients with high levels of each protein had the longest survival times following adjuvant therapy with gemcitabine. High levels of hENT1 and dCK in PDAC predict longer survival times in patients treated with adjuvant gemcitabine. Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.

Effects of 12-O-tetradecanoylphorbol-13-acetate in combination with gemcitabine on Panc-1 pancreatic cancer cells cultured in vitro or Panc-1 tumors grown in immunodeficient mice.

PubMed

Zheng, Xi; Cui, Xiao-Xing; Gao, Zhi; Verano, Michael; Huang, Mou-Tuan; Liu, Yue; Rabson, Arnold B; Conney, Allan H

2012-12-01

In the present study, the effects of 12-O-tetra-decanoylphorbol-13-acetate (TPA) alone or in combination with gemcitabine on the growth of Panc-1 pancreatic cancer cells cultured in vitro or grown in NCr immunodeficient nude mice were investigated. Combinations of TPA and gemcitabine synergi-stically inhibited the growth and induced apoptosis in Panc-1 cells. The combination of TPA (0.16 nM) and gemcitabine (0.5 µM) induced a marked increase in phosphorylated c-Jun NH2-terminal kinase (JNK) in the Panc-1 cells. In animal experiments, NCr nude mice with established Panc-1 tumors received daily intraperitoneal (i.p.) injections of TPA (50 ng/g body weight/day) or gemcitabine (0.5 µg/g body weight/day) alone or in combination for 26 days. Treatment with daily i.p. injections of low doses of TPA or gemcitabine alone had a modest inhibitory effect on the growth of the tumors. However, the combination of low doses of TPA and gemcitabine more potently inhibited the growth of Panc-1 tumors than either agent used individually. Treatment with TPA or gemcitabine alone or in combination did not affect the body weight of the animals. Clinical trials with TPA alone or in combination with gemcitabine on patients with pancreatic cancer are warranted in order to confirm our results.

Adjuvant Gemcitabine and Gemcitabine-based Chemoradiotherapy Versus Gemcitabine Alone After Pancreatic Cancer Resection: The Indiana University Experience.

PubMed

Khawaja, Muhammad R; Kleyman, Svetlana; Yu, Zhangsheng; Howard, Thomas; Burns, Matthew; Nakeeb, Attila; Loehrer, Patrick J; Cardenes, Higinia R; Chiorean, Elena Gabriela

2017-02-01

Adjuvant therapy after surgical resection is the current standard for pancreatic adenocarcinoma; however, the role of chemoradiotherapy (CRT) remains unclear. This study was conducted to compare the efficacy outcomes with adjuvant gemcitabine and gemcitabine-based CRT (CT-CRT) versus gemcitabine chemotherapy (CT) alone after pancreaticoduodenectomy. Among 165 patients who underwent surgical resection for pancreatic cancer at Indiana University Medical Center between 2004 and 2008, we retrospectively identified 53 consecutive patients who received adjuvant therapy (CT-CRT=34 patients; CT=19 patients) and had adequate follow-up medical records. The median follow-up was 19.1 months. Median disease-free (DFS) and overall survival (OS) were determined using Kaplan-Meier method, and a Cox-regression model was used to compare survival outcomes after adjusting for age, status of resection margins, and lymph node involvement. The OS for the CT-CRT group was significantly higher compared with the CT group (median, 20.4 vs. 16.6 mo; hazard ratio, 2.42; 95% CI, 1.17-5.01). The median DFS for the CT-CRT group was 13.7 versus 11.1 months for the CT group (hazard ratio, 2.88; 95% CI, 1.37-6.06). On subgroup analyses, significantly superior OS and DFS were observed among patients younger than 65 years, T3/T4 tumor stage, negative resection margins, and positive lymph node involvement. Gemcitabine plus gemcitabine-based CRT compared with gemcitabine alone leads to superior DFS and OS for patients with resected pancreatic cancer.

Necitumumab plus gemcitabine and cisplatin versus gemcitabine and cisplatin alone as first-line therapy in patients with stage IV squamous non-small-cell lung cancer (SQUIRE): an open-label, randomised, controlled phase 3 trial.

PubMed

Thatcher, Nick; Hirsch, Fred R; Luft, Alexander V; Szczesna, Aleksandra; Ciuleanu, Tudor E; Dediu, Mircea; Ramlau, Rodryg; Galiulin, Rinat K; Bálint, Beatrix; Losonczy, György; Kazarnowicz, Andrzej; Park, Keunchil; Schumann, Christian; Reck, Martin; Depenbrock, Henrik; Nanda, Shivani; Kruljac-Letunic, Anamarija; Kurek, Raffael; Paz-Ares, Luis; Socinski, Mark A

2015-07-01

Necitumumab is a second-generation, recombinant, human immunoglobulin G1 EGFR antibody. In this study, we aimed to compare treatment with necitumumab plus gemcitabine and cisplatin versus gemcitabine and cisplatin alone in patients with previously untreated stage IV squamous non-small-cell lung cancer. We did this open-label, randomised phase 3 study at 184 investigative sites in 26 countries. Patients aged 18 years or older with histologically or cytologically confirmed stage IV squamous non-small-cell lung cancer, with an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2 and adequate organ function and who had not received previous chemotherapy for their disease were eligible for inclusion. Enrolled patients were randomly assigned centrally 1:1 to a maximum of six 3-week cycles of gemcitabine and cisplastin chemotherapy with or without necitumumab according to a block randomisation scheme (block size of four) by a telephone-based interactive voice response system or interactive web response system. Chemotherapy was gemcitabine 1250 mg/m(2) administered intravenously over 30 min on days 1 and 8 of a 3-week cycle and cisplatin 75 mg/m(2) administered intravenously over 120 min on day 1 of a 3-week cycle. Necitumumab 800 mg, administered intravenously over a minimum of 50 min on days 1 and 8, was continued after the end of chemotherapy until disease progression or intolerable toxic side-effects occurred. Randomisation was stratified by ECOG performance status and geographical region. Neither physicians nor patients were masked to group assignment because of the expected occurrence of acne-like rash--a class effect of EGFR antibodies--that would have unmasked most patients and investigators to treatment. The primary endpoint was overall survival, analysed by intention to treat. We report the final clinical analysis. This study is registered with ClinicalTrials.gov, number NCT00981058. Between Jan 7, 2010, and Feb 22, 2012, we enrolled 1093 patients and randomly assigned them to receive necitumumab plus gemcitabine and cisplatin (n=545) or gemcitabine and cisplatin (n=548). Overall survival was significantly longer in the necitumumab plus gemcitabine and cisplatin group than in the gemcitabine and cisplatin alone group (median 11·5 months [95% CI 10·4-12·6]) vs 9·9 months [8·9-11·1]; stratified hazard ratio 0·84 [95% CI 0·74-0·96; p=0·01]). In the necitumumab plus gemcitabine and cisplatin group, the number of patients with at least one grade 3 or worse adverse event was higher (388 [72%] of 538 patients) than in the gemcitabine and cisplatin group (333 [62%] of 541), as was the incidence of serious adverse events (257 [48%] of 538 patients vs 203 [38%] of 541). More patients in the necitumumab plus gemcitabine and cisplatin group had grade 3-4 hypomagnesaemia (47 [9%] of 538 patients in the necitumumab plus gemcitabine and cisplatin group vs six [1%] of 541 in the gemcitabine and cisplatin group) and grade 3 rash (20 [4%] vs one [<1%]). Including events related to disease progression, adverse events with an outcome of death were reported for 66 (12%) of 538 patients in the necitumumab plus gemcitabine and cisplatin group and 57 (11%) of 541 patients in the gemcitabine and cisplatin group; these were deemed to be related to study drugs in 15 (3%) and ten (2%) patients, respectively. Overall, we found that the safety profile of necitumumab plus gemcitabine and cisplatin was acceptable and in line with expectations. Our findings show that the addition of necitumumab to gemcitabine and cisplatin chemotherapy improves overall survival in patients with advanced squamous non-small-cell lung cancer and represents a new first-line treatment option for this disease. Eli Lilly and Company. Copyright © 2015 Elsevier Ltd. All rights reserved.

Gemcitabine Hydrochloride, Carboplatin, Dexamethasone, and Rituximab in Treating Patients With Previously Treated Lymphoid Malignancies

ClinicalTrials.gov

2017-05-28

Adult Nasal Type Extranodal NK/T-cell Lymphoma; Anaplastic Large Cell Lymphoma; Angioimmunoblastic T-cell Lymphoma; Cutaneous B-cell Non-Hodgkin Lymphoma; Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Hepatosplenic T-cell Lymphoma; Intraocular Lymphoma; Nodal Marginal Zone B-cell Lymphoma; Noncutaneous Extranodal Lymphoma; Peripheral T-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Grade III Lymphomatoid Granulomatosis; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Mycosis Fungoides/Sezary Syndrome; Recurrent Small Lymphocytic Lymphoma; Small Intestine Lymphoma; Splenic Marginal Zone Lymphoma; Testicular Lymphoma; Waldenstrom Macroglobulinemia

Nab-Paclitaxel Plus Gemcitabine for Metastatic Pancreatic Cancer

Cancer.gov

A summary of results from a phase III trial that compared the combination of albumin-bound paclitaxel (nab-paclitaxel [Abraxane®]) and gemcitabine (Gemzar®) versus gemcitabine alone in patients with metastatic pancreatic cancer.

Nab-paclitaxel and Gemcitabine vs Gemcitabine Alone as Adjuvant Therapy for Patients With Resected Pancreatic Cancer (the "Apact" Study)

ClinicalTrials.gov

2018-03-26

Pancreatic Neoplasms; Digestive System Neoplasms; Neoplasms by Site; Neoplasms; Endocrine Gland Neoplasms; Pancreatic Diseases; Digestive System Diseases; Endocrine System Diseases; Gemcitabine; Antimetabolites, Antineoplastic

P300 inhibition enhances gemcitabine-induced apoptosis of pancreatic cancer

PubMed Central

Ono, Hiroaki; Basson, Marc D.; Ito, Hiromichi

2016-01-01

The transcriptional cofactor p300 has histone acetyltransferase activity (HAT) and has been reported to participate in chromatin remodeling and DNA repair. We hypothesized that targeting p300 can enhance the cytotoxicity of gemcitabine, which induces pancreatic cancer cell apoptosis by damaging DNA. Expression of p300 was confirmed in pancreatic cancer cell lines and human pancreatic adenocarcinoma tissues by western blotting and immunohistochemistry. When pancreatic cancer cells were treated with gemcitabine, p300 was recruited to chromatin within 24 hours, indicating the role in response to DNA damage. When p300 was gene-silenced with siRNA, histone acetylation was substantially reduced and pancreatic cancer cells were sensitized to gemcitabine. The selective p300 HAT inhibitor C646 similarly decreased histone acetylation, increased gemcitabine-induced apoptosis and thus enhanced the cytotoxicity of gemcitabine on pancreatic cancer cells. These findings indicate that p300 contributes to chemo-resistance of pancreatic cancer against gemcitabine and suggest that p300 and its HAT activity may be a potential therapeutic target to improve outcomes in patients with pancreatic cancer. PMID:27322077

Inhibition of heme oxygenase-1 enhances the cytotoxic effect of gemcitabine in urothelial cancer cells.

PubMed

Miyake, Makito; Fujimoto, Kiyohide; Anai, Satoshi; Ohnishi, Sayuri; Nakai, Yasushi; Inoue, Takeshi; Matsumura, Yoshiaki; Tomioka, Atsushi; Ikeda, Tomohiro; Okajima, Eijiro; Tanaka, Nobumichi; Hirao, Yoshihiko

2010-06-01

Elevated heme oxygenase-1 (HO-1) is associated with resistance to chemo- and radiotherapy through anti-apoptotic function. The present study evaluated whether the HO-1 inhibitor, zinc protoporphyrin IX (ZnPP), enhances the cytotoxic effect of gemcitabine in urothelial carcinoma (UC). The in vitro cytotoxic effect of combination treatment of gemcitabine and ZnPP on UC cells was examined. The in vivo growth inhibitory effects of intraperitoneal administration of gemcitabine and/or ZnPP on mouse subcutaneous tumours were examined. The apoptotic changes were analysed with the detection of DNA fragmentation and cleaved caspase-3. HO-1 was up-regulated by both gemcitabine and irradiation treatment in vitro. ZnPP sensitised the UC cells to both therapies. Enhanced apoptosis was induced by the ZnPP combined with gemicitabine. ZnPP enhanced the antitumour effect of gemcitabine in vivo along with decreased numbers of proliferating cells and increased numbers of apoptotic cells. These findings suggest that ZnPP combined with gemcitabine or irradiation therapy may be an effective therapeutic modality for UC patients.

Synergistic effect of sequential administration of mitoguazone (MGBG) and gemcitabine in treating tissue cultured human breast cancer cells and mammary rat tumors.

PubMed

Ishmael, D Richard; Chen, Wei R; Nordquist, John A; Liu, Hong; Nordquist, Robert E

2003-04-01

Modulation of cancer chemotherapeutic drugs has been attempted to increase efficacy and overcome resistance to the chemotherapeutic agent. Studies have shown schedule-dependent interactions in combined use of chemotherapeutic drugs. Mitoguazone (MGBG), an old drug with possible modulating activity, was used in combination with gemcitabine, a relatively new cancer drug, in treating tissue cultured human breast cancer cells and mammary rat tumors. Tissue cultured BOT-2 cancer cells were first treated with varying concentrations of gemcitabine and MGBG, independently. Combinations of the two drugs were then used with different scheduled administrations. Marked synergistic activity was found between gemcitabine and MGBG when the MGBG was given first, followed by gemcitabine 24 hours later. A non-toxic dose of MGBG enhanced the toxicity of gemcitabine by eight orders of magnitude using MTT assays in the tissue cultured human breast cancer cell study. The sequential administration of MGBG and gemcitabine also increased the survival rate of rats bearing mammary tumors in our pilot animal study.

Structural basis for the selective permeability of channels made of communicating junction proteins.

PubMed

Ek-Vitorin, Jose F; Burt, Janis M

2013-01-01

The open state(s) of gap junction channels is evident from their permeation by small ions in response to an applied intercellular (transjunctional/transchannel) voltage gradient. That an open channel allows variable amounts of current to transit from cell-to-cell in the face of a constant intercellular voltage difference indicates channel open/closing can be complete or partial. The physiological significance of such open state options is, arguably, the main concern of junctional regulation. Because gap junctions are permeable to many substances, it is sensible to inquire whether and how each open state influences the intercellular diffusion of molecules as valuable as, but less readily detected than current-carrying ions. Presumably, structural changes perceived as shifts in channel conductivity would significantly alter the transjunctional diffusion of molecules whose limiting diameter approximates the pore's limiting diameter. Moreover, changes in junctional permeability to some molecules might occur without evident changes in conductivity, either at macroscopic or single channel level. Open gap junction channels allow the exchange of cytoplasmic permeants between contacting cells by simple diffusion. The identity of such permeants, and the functional circumstances and consequences of their junctional exchange presently constitute the most urgent (and demanding) themes of the field. Here, we consider the necessity for regulating this exchange, the possible mechanism(s) and structural elements likely involved in such regulation, and how regulatory phenomena could be perceived as changes in chemical vs. electrical coupling; an overall reflection on our collective knowledge of junctional communication is then applied to suggest new avenues of research. This article is part of a Special Issue entitled: The Communicating junctions, roles and dysfunctions. Copyright © 2012 Elsevier B.V. All rights reserved.

Protein Equilibration through Somatic Ring Canals in Drosophila

PubMed Central

McLean, Peter F.; Cooley, Lynn

2013-01-01

Although intercellular bridges resulting from incomplete cytokinesis were discovered in somatic Drosophila tissues decades ago, the impact of these structures on intercellular communication and tissue biology is largely unknown. In this work, we demonstrate that the ~250 nm diameter somatic ring canals permit diffusion of cytoplasmic contents between connected cells and across mitotic clone boundaries, and enable the equilibration of protein between transcriptionally mosaic follicle cells in the Drosophila ovary. We obtained similar, though more restricted, results in the larval imaginal discs. Our work illustrates the lack of cytoplasmic autonomy in these tissues and suggests a role for somatic ring canals in promoting homogeneous protein expression within the tissue. PMID:23704373

CHD7 Expression Predicts Survival Outcomes in Patients with Resected Pancreatic Cancer

PubMed Central

Colbert, Lauren E.; Petrova, Aleksandra V.; Fisher, Sarah B.; Pantazides, Brooke G.; Madden, Matthew Z.; Hardy, Claire W.; Warren, Matthew D.; Pan, Yunfeng; Nagaraju, Ganji P.; Liu, Elaine A.; Saka, Burcu; Hall, William A.; Shelton, Joseph W.; Gandhi, Khanjan; Pauly, Rini; Kowalski, Jeanne; Kooby, David A.; El-Rayes, Bassel F.; Staley, Charles A.; Adsay, N. Volkan; Curran, Walter J.; Landry, Jerome C.; Maithel, Shishir K.; Yu, David S.

2014-01-01

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease with poor outcomes with current therapies. Gemcitabine is the primary adjuvant drug used clinically, but its effectiveness is limited. In this study, our objective was to utilize a rationale-driven approach to identify novel biomarkers for outcome in patients with early-stage resected PDAC treated with adjuvant gemcitabine. Using a synthetic lethal screen in human PDAC cells, we identified 93 genes including 55 genes linked to DNA damage responses (DDR) that demonstrated gemcitabine sensitization when silenced, including CHD7 which functions in chromatin remodeling. CHD7 depletion sensitized PDAC cells to gemcitabine and delayed their growth in tumor xenografts. Moreover, CHD7 silencing impaired ATR-dependent phosphorylation of CHK1 and increased DNA damage induced by gemcitabine. CHD7 was dysregulated, ranking above the 90th percentile in differential expression in a panel of PDAC clinical specimens, highlighting its potential as a biomarker. Immunohistochemical analysis of specimens from 59 resected PDAC patients receiving adjuvant gemcitabine revealed that low CHD7 expression was associated with increased recurrence-free survival (RFS) and overall survival (OS), in univariate and multivariate analyses. Notably, CHD7 expression was not associated with RFS or OS for patients not receiving gemcitabine. Thus, low CHD7 expression was correlated selectively with gemcitabine sensitivity in this patient population. These results supported our rationale-driven strategy to exploit dysregulated DDR pathways in PDAC to identify genetic determinants of gemcitabine sensitivity, identifying CHD7 as a novel biomarker candidate to evaluate further for individualizing PDAC treatment. PMID:24626090

A phase I study assessing the safety and pharmacokinetics of the thrombospondin-1-mimetic angiogenesis inhibitor ABT-510 with gemcitabine and cisplatin in patients with solid tumors.

PubMed

Gietema, J A; Hoekstra, R; de Vos, F Y F L; Uges, D R A; van der Gaast, A; Groen, H J M; Loos, W J; Knight, R A; Carr, R A; Humerickhouse, R A; Eskens, F A L M

2006-08-01

The aim of the study was to determine the safety profile, pharmacokinetics and potential drug interactions of the angiogenesis inhibitor ABT-510 combined with gemcitabine-cisplatin chemotherapy in patients with solid tumors. Patients with advanced solid tumors received gemcitabine 1250 mg/m2 intravenously (i.v.) on days 1 and 8 and cisplatin 80 mg/m2 on day 1 of a 3-week cycle in combination with ABT-510. ABT-510 was administered subcutaneously twice daily at doses of 50 mg or 100 mg. Plasma samples for pharmacokinetics were obtained on days 1 (gemcitabine, cisplatin as single agents), 15 (ABT-510 as single agent) and 22 (gemcitabine, cisplatin and ABT-510 as combination). Thirteen patients received ABT-510 as either 50 mg b.i.d. (seven patients) or 100 mg b.i.d. (six patients) in combination with gemcitabine-cisplatin. The most common reported adverse events reflected the known toxicity profile induced by gemcitabine-cisplatin without ABT-510. One episode of hemoptysis occurred in a patient with non-small-cell lung cancer (NSCLC) after 13 days of treatment. No clinically significant pharmacokinetic interactions between ABT-510, gemcitabine and platinum were observed. Three partial responses were observed in 12 evaluable patients (one head and neck cancer, one melanoma and one NSCLC). Combining ABT-510 at doses of 50 mg and 100 mg with gemcitabine-cisplatin is feasible. Pharmacokinetic interactions were not observed and adding ABT-510 does not appear to increase toxicity.

Phase I study of olaparib plus gemcitabine in patients with advanced solid tumours and comparison with gemcitabine alone in patients with locally advanced/metastatic pancreatic cancer.

PubMed

Bendell, J; O'Reilly, E M; Middleton, M R; Chau, I; Hochster, H; Fielding, A; Burke, W; Burris, H

2015-04-01

Olaparib (Lynparza) is an oral poly(adenosine diphosphate [ADP]-ribose) polymerase inhibitor that induces synthetic lethality in cancers with homologous recombination defects. In this phase I, dose-escalation trial, patients with advanced solid tumours received olaparib (50-200 mg capsules b.i.d.) continuously or intermittently (days 1-14, per 28-day cycle) plus gemcitabine [i.v. 600-800 mg/m(2); days 1, 8, 15, and 22 (cycle 1), days 1, 8, and 15 (subsequent cycles)] to establish the maximum tolerated dose. A separate dose-escalation phase evaluated olaparib in tablet formulation (100 mg o.d./b.i.d.; days 1-14) plus gemcitabine (600 mg/m(2)). In an expansion phase, patients with genetically unselected locally advanced or metastatic pancreatic cancer were randomised 2 : 1 to the tolerated olaparib capsule combination dose or gemcitabine alone (1000 mg/m(2)). Sixty-six patients were treated [dose-escalation phase, n = 44 (tablet cohort, n = 12); dose-expansion phase, n = 22 (olaparib plus gemcitabine, n = 15; gemcitabine alone, n = 7)]. In the dose-escalation phase, four patients (6%) experienced dose-limiting toxicities (raised alanine aminotransferase, n = 2; neutropenia, n = 1; febrile neutropenia, n = 1). Grade ≥3 adverse events were reported in 38/47 patients (81%) treated with olaparib capsules plus gemcitabine; most common were haematological toxicities (55%). Tolerated combinations were olaparib 100 mg b.i.d. capsule (intermittently, days 1-14) plus gemcitabine 600 mg/m(2) and olaparib 100 mg o.d. tablet (intermittently, days 1-14) plus gemcitabine 600 mg/m(2). There were no differences in efficacy observed during the dose-expansion phase. Olaparib 100 mg b.i.d. (intermittent dosing; capsules) plus gemcitabine 600 mg/m(2) is tolerated in advanced solid tumour patients, with no unmanageable/unexpected toxicities. Continuous dosing of olaparib or combination with gemcitabine at doses >600 mg/m(2) was not considered to have an acceptable tolerability profile for further study. NCT00515866. © The Author 2015. Published by Oxford University Press on behalf of the European Society for Medical Oncology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Phase I/II trial of doxorubicin and fixed dose-rate infusion gemcitabine in advanced soft tissue sarcomas: a GEIS study

PubMed Central

López-Pousa, A; Losa, R; Martín, J; Maurel, J; Fra, J; Sierra, M; Casado, A; García del Muro, J; Poveda, A; Balañá, C; Martínez-Trufero, J; Esteban, E; Buesa, J M

2006-01-01

The aim of the study was to determine the dose-limiting toxicity and maximum tolerated dose of a first-line combination of doxorubicin and gemcitabine in adult patients with advanced soft tissue sarcomas and to explore its activity and toxicity, and the presence of possible interactions between these agents. Patients with measurable disease were initially treated with doxorubicin 60 mg m−2 by i.v. bolus on day 1 followed by gemcitabine at 800 mg m−2 over 80 min on days 1 and 8, every 21 days. Concentrations of gemcitabine and 2′,2′-difluorodeoxyuridine in plasma, and gemcitabine triphosphate levels in peripheral blood mononuclear cells were determined during 8 h after the start of gemcitabine infusion. Myelosuppression and stomatitis were limiting toxicities, and the initial dose level was applied for the Phase II trial, where grade 3–4 granulocytopenia occurred in 70% of patients, grade 3 stomatitis in 46% and febrile neutropenia in 20%. Objective activity in 36 patients was 22% (95% CI: 9–35%), and a 50% remission rate was noted in leiomyosarcomas. Administration of doxorubicin preceding gemcitabine significantly reduced the synthesis of gemcitabine triphosphate. Clinical activity, similar to that of single-agent doxorubicin, and the toxicity encountered do not justify further studies with this schedule of administration. PMID:16721358

A phase IB study of the pharmacokinetics of gemcitabine and pemetrexed, when administered in rapid sequence to patients with advanced solid tumors.

PubMed

Dy, Grace K; Suri, Ajit; Reid, Joel M; Sloan, Jeff A; Pitot, Henry C; Alberts, Steven R; Goldberg, Richard M; Atherton, Pamela J; Hanson, Lorelei J; Burch, Patrick A; Rubin, Joseph; Erlichman, Charles; Adjei, Alex A

2005-06-01

We have previously demonstrated that pemetrexed is clinically active when administered 90 min after gemcitabine in a phase I study. The present study was undertaken to evaluate the efficacy, toxicity, and pharmacokinetics of gemcitabine and pemetrexed when pemetrexed is administered immediately after gemcitabine. A total of 14 patients received 84 cycles of treatment. Gemcitabine 1250 mg/m(2) was administered on days 1 and 8 of each 21-day cycle, and pemetrexed 500 mg/m(2) on day 8 immediately following gemcitabine administration. Toxicities were graded according to the National Cancer Institute Common Toxicity Criteria and recorded as maximum grade per patient for all treatment cycles. Pharmacokinetic analyses of plasma gemcitabine and pemetrexed concentrations were performed. Neutropenia was the most common severe toxicity. Non-hematologic toxicities, which included nausea, vomiting, fatigue, diarrhea, rash, and elevated transaminases were of mild-to-moderate severity. No increased toxicity was observed with this schedule in comparison to the previous phase I schedule. There was no pharmacokinetic interaction between the two drugs. One partial response was documented in a patient with non-small-cell lung cancer. Eight patients had disease stabilization for five or more cycles. Gemcitabine immediately followed by pemetrexed is well tolerated and clinically active, and deserves further evaluation in phase II trials.

A double-blind placebo-controlled, randomised study comparing gemcitabine and marimastat with gemcitabine and placebo as first line therapy in patients with advanced pancreatic cancer

PubMed Central

Bramhall, S R; Schulz, J; Nemunaitis, J; Brown, P D; Baillet, M; Buckels, J A C

2002-01-01

Pancreatic cancer is the fifth most common cause of cancer death in the western world and the prognosis for unresectable disease remains poor. Recent advances in conventional chemotherapy and the development of novel ‘molecular’ treatment strategies with different toxicity profiles warrant investigation as combination treatment strategies. This randomised study in pancreatic cancer compares marimastat (orally administered matrix metalloproteinase inhibitor) in combination with gemcitabine to gemcitabine alone. Two hundred and thirty-nine patients with unresectable pancreatic cancer were randomised to receive gemcitabine (1000 mg m−2) in combination with either marimastat or placebo. The primary end-point was survival. Objective tumour response and duration of response, time to treatment failure and disease progression, quality of life and safety were also assessed. There was no significant difference in survival between gemcitabine and marimastat and gemcitabine and placebo (P=0.95 log-rank test). Median survival times were 165.5 and 164 days and 1-year survival was 18% and 17% respectively. There were no significant differences in overall response rates (11 and 16% respectively), progression-free survival (P=0.68 log-rank test) or time to treatment failure (P=0.70 log-rank test) between the treatment arms. The gemcitabine and marimastat combination was well tolerated with only 2.5% of patients withdrawn due to presumed marimastat toxicity. Grade 3 or 4 musculoskeletal toxicities were reported in only 4% of the marimastat treated patients, although 59% of marimastat treated patients reported some musculoskeletal events. The results of this study provide no evidence to support a combination of marimastat with gemcitabine in patients with advanced pancreatic cancer. The combination of marimastat with gemcitabine was well tolerated. Further studies of marimastat as a maintenance treatment following a response or stable disease on gemcitabine may be justified. British Journal of Cancer (2002) 87, 161–167. doi:10.1038/sj.bjc.6600446 www.bjcancer.com © 2002 Cancer Research UK PMID:12107836

Cost-effectiveness of modern radiotherapy techniques in locally advanced pancreatic cancer.

PubMed

Murphy, James D; Chang, Daniel T; Abelson, Jon; Daly, Megan E; Yeung, Heidi N; Nelson, Lorene M; Koong, Albert C

2012-02-15

Radiotherapy may improve the outcome of patients with pancreatic cancer but at an increased cost. In this study, the authors evaluated the cost-effectiveness of modern radiotherapy techniques in the treatment of locally advanced pancreatic cancer. A Markov decision-analytic model was constructed to compare the cost-effectiveness of 4 treatment regimens: gemcitabine alone, gemcitabine plus conventional radiotherapy, gemcitabine plus intensity-modulated radiotherapy (IMRT); and gemcitabine with stereotactic body radiotherapy (SBRT). Patients transitioned between the following 5 health states: stable disease, local progression, distant failure, local and distant failure, and death. Health utility tolls were assessed for radiotherapy and chemotherapy treatments and for radiation toxicity. SBRT increased life expectancy by 0.20 quality-adjusted life years (QALY) at an increased cost of $13,700 compared with gemcitabine alone (incremental cost-effectiveness ratio [ICER] = $69,500 per QALY). SBRT was more effective and less costly than conventional radiotherapy and IMRT. An analysis that excluded SBRT demonstrated that conventional radiotherapy had an ICER of $126,800 per QALY compared with gemcitabine alone, and IMRT had an ICER of $1,584,100 per QALY compared with conventional radiotherapy. A probabilistic sensitivity analysis demonstrated that the probability of cost-effectiveness at a willingness to pay of $50,000 per QALY was 78% for gemcitabine alone, 21% for SBRT, 1.4% for conventional radiotherapy, and 0.01% for IMRT. At a willingness to pay of $200,000 per QALY, the probability of cost-effectiveness was 73% for SBRT, 20% for conventional radiotherapy, 7% for gemcitabine alone, and 0.7% for IMRT. The current results indicated that IMRT in locally advanced pancreatic cancer exceeds what society considers cost-effective. In contrast, combining gemcitabine with SBRT increased clinical effectiveness beyond that of gemcitabine alone at a cost potentially acceptable by today's standards. Copyright © 2011 American Cancer Society.

Synthetic lethal RNAi screening identifies sensitizing targets for gemcitabine therapy in pancreatic cancer

PubMed Central

Azorsa, David O; Gonzales, Irma M; Basu, Gargi D; Choudhary, Ashish; Arora, Shilpi; Bisanz, Kristen M; Kiefer, Jeffrey A; Henderson, Meredith C; Trent, Jeffrey M; Von Hoff, Daniel D; Mousses, Spyro

2009-01-01

Background Pancreatic cancer retains a poor prognosis among the gastrointestinal cancers. It affects 230,000 individuals worldwide, has a very high mortality rate, and remains one of the most challenging malignancies to treat successfully. Treatment with gemcitabine, the most widely used chemotherapeutic against pancreatic cancer, is not curative and resistance may occur. Combinations of gemcitabine with other chemotherapeutic drugs or biological agents have resulted in limited improvement. Methods In order to improve gemcitabine response in pancreatic cancer cells, we utilized a synthetic lethal RNAi screen targeting 572 known kinases to identify genes that when silenced would sensitize pancreatic cancer cells to gemcitabine. Results Results from the RNAi screens identified several genes that, when silenced, potentiated the growth inhibitory effects of gemcitabine in pancreatic cancer cells. The greatest potentiation was shown by siRNA targeting checkpoint kinase 1 (CHK1). Validation of the screening results was performed in MIA PaCa-2 and BxPC3 pancreatic cancer cells by examining the dose response of gemcitabine treatment in the presence of either CHK1 or CHK2 siRNA. These results showed a three to ten-fold decrease in the EC50 for CHK1 siRNA-treated cells versus control siRNA-treated cells while treatment with CHK2 siRNA resulted in no change compared to controls. CHK1 was further targeted with specific small molecule inhibitors SB 218078 and PD 407824 in combination with gemcitabine. Results showed that treatment of MIA PaCa-2 cells with either of the CHK1 inhibitors SB 218078 or PD 407824 led to sensitization of the pancreatic cancer cells to gemcitabine. Conclusion These findings demonstrate the effectiveness of synthetic lethal RNAi screening as a tool for identifying sensitizing targets to chemotherapeutic agents. These results also indicate that CHK1 could serve as a putative therapeutic target for sensitizing pancreatic cancer cells to gemcitabine. PMID:19519883

Overcoming S-Phase Checkpoint-Mediated Resistance: Sequence-Dependent Synergy of Gemcitabine and SN-38 In Human Carcinoma Cell Lines*

PubMed Central

Gálvez-Peralta, Marina; Dai, Nga T.; Loegering, David A.; Flatten, Karen; Safgren, Stephanie; Wagner, Jill; Ames, Matthew M.; Karnitz, Larry M.; Kaufmann, Scott H.

2008-01-01

Although agents that inhibit DNA synthesis are widely used in the treatment of cancer, the optimal method for combining such agents and the mechanism of their synergy is poorly understood. The present study examined the effects of combining gemcitabine and SN-38 (the active metabolite of irinotecan), two S phase-selective agents that individually have broad antitumor activity, in human cancer cells in vitro. Colony forming assays revealed that simultaneous treatment of Ovcar-5 ovarian cancer cells or BxPC-3 pancreatic cancer cells with gemcitabine and SN-38 resulted in antagonistic effects. In contrast, sequential treatment with the two agents in either order resulted in synergistic antiproliferative effects, although the mechanism of synergy varied with the sequence. In particular, SN-38 arrested cells in S phase, enhanced the accumulation of gemcitabine metabolites and diminished checkpoint kinase 1, thereby sensitizing cells in the SN-38 → gemcitabine sequence. Gemcitabine treatment followed by removal allowed prolonged progression through S phase, contributing to synergy of the gemcitabine → SN-38 sequence. Collectively, these results suggest that S phase selective agents might exhibit more cytotoxicity when administered sequentially rather than simultaneously. PMID:18509065

SL-01, an oral derivative of gemcitabine, inhibited human breast cancer growth through induction of apoptosis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Yuan-Yuan; Qin, Yi-Zhuo; Wang, Rui-Qi

Highlights: •SL-01 is an oral derivative of gemcitabine. •SL-01 possessed activity against human breast cancer growth via apoptotic induction. •SL-01’s activity was more potently than that of gemcitabine. •SL-01 inhibited cancer growth without toxicity to mice. -- Abstract: SL-01 is an oral derivative of gemcitabine that was synthesized by introducing the moiety of 3-(dodecyloxycarbonyl) pyrazine-2-carbonyl at N4-position on cytidine ring of gemcitabine. We aimed to evaluate the efficacy of SL-01 on human breast cancer growth. SL-01 significantly inhibited MCF-7 proliferation as estimated by colorimetric assay. Flow cytometry assay indicated the apoptotic induction and cell cycle arrest in G1 phase. SL-01more » modulated the expressions of p-ATM, p53 and p21 and decrease of cyclin D1 in MCF-7 cells. Further experiments were performed in a MCF-7 xenografts mouse model. SL-01 by oral administration strongly inhibited MCF-7 xenografts growth. This effect of SL-01 might arise from its roles in the induction of apoptosis. Immunohistochemistry assay showed the increase of TUNEL staining cells. Western blotting indicated the modulation of apoptotic proteins in SL-01-treated xenografts. During the course of study, there was no evidence of toxicity to mice. In contrast, the decrease of neutrophil cells in peripheral and increase of AST and ALT levels in serum were observed in the gemcitabine-treated mice. Conclusion: SL-01 possessed similar activity against human breast cancer growth with gemcitabine, whereas, with lower toxicity to gemcitabine. SL-01 is a potent oral agent that may supplant the use of gemcitabine.« less

Preparation, Optimization and Toxicity Evaluation of (SPION-PLGA) ±PEG Nanoparticles Loaded with Gemcitabine as a Multifunctional Nanoparticle for Therapeutic and Diagnostic Applications.

PubMed

Hamzian, Nima; Hashemi, Maryam; Ghorbani, Mahdi; Bahreyni Toosi, Mohammad Hossein; Ramezani, Mohammad

2017-01-01

The aim of this study was to develop a novel multifunctional nanoparticle, which encapsulates SPION and Gemcitabine in PLGA ± PEG to form multifunctional drug delivery system. For this aim, super paramagnetic iron oxide nanoparticles (SPIONs) were simultaneously synthesized and encapsulated with Gemcitabine (Gem) in PLGA ± PEG copolymers via W/O/W double emulsification method. Optimum size and encapsulation efficiency for radiosensitization, hyperthermia and diagnostic applications were considered and the preparation parameters systematically were investigated and physicochemical characteristics of optimized nanoparticle were studied. Then SPION-PLGA and PLGA-Gem nanoparticles were prepared with the same optimized parameters and the toxicity of these nanoparticles was compared with Gemcitabine in human breast cancer cell line (MCF-7). The optimum preparation parameters were obtained with Gem/polymer equal to 0.04, SPION/polymer equal to 0.8 and 1% sucrose per 20 mg of polymer. The hydrodynamic diameters of all nanoparticles were under 200 nm. Encapsulation efficiency was adjusted between 13.2% to 16.1% for Gemcitabine and 48.2% to 50.1% for SPION. In-vitro Gemcitabine release kinetics had controlled behavior. Enhancement ratios for PLGA-Gem and SPION-PLGA-Gem at concentration of nanoparticles equal to IC50 of Gemcitabine were 1.53 and 1.89 respectively. The statistical difference was significant ( p -value = 0.006 for SPION-PLGA-Gem and p -value = 0.015 for PLGA-Gem compared with Gemcitabine). In conclusion, we have successfully developed a Gemcitabine loaded super paramagnetic PLGA-Iron Oxide multifunctional drag delivery system. Future work includes in-vitro and in-vivo investigation of radiosensitization and other application of these nanoparticles.

Oblimersen and Gemcitabine in Treating Patients With Advanced Solid Tumor or Lymphoma

ClinicalTrials.gov

2013-01-24

Extranodal Marginal Zone B-cell Lymphoma of Mucosa-associated Lymphoid Tissue; Nodal Marginal Zone B-cell Lymphoma; Recurrent Adult Burkitt Lymphoma; Recurrent Adult Diffuse Large Cell Lymphoma; Recurrent Adult Diffuse Mixed Cell Lymphoma; Recurrent Adult Diffuse Small Cleaved Cell Lymphoma; Recurrent Adult Hodgkin Lymphoma; Recurrent Adult Immunoblastic Large Cell Lymphoma; Recurrent Adult Lymphoblastic Lymphoma; Recurrent Adult T-cell Leukemia/Lymphoma; Recurrent Cutaneous T-cell Non-Hodgkin Lymphoma; Recurrent Grade 1 Follicular Lymphoma; Recurrent Grade 2 Follicular Lymphoma; Recurrent Grade 3 Follicular Lymphoma; Recurrent Mantle Cell Lymphoma; Recurrent Marginal Zone Lymphoma; Recurrent Small Lymphocytic Lymphoma; Splenic Marginal Zone Lymphoma; Stage IV Adult Burkitt Lymphoma; Stage IV Adult Diffuse Large Cell Lymphoma; Stage IV Adult Diffuse Mixed Cell Lymphoma; Stage IV Adult Diffuse Small Cleaved Cell Lymphoma; Stage IV Adult Hodgkin Lymphoma; Stage IV Adult Immunoblastic Large Cell Lymphoma; Stage IV Adult Lymphoblastic Lymphoma; Stage IV Adult T-cell Leukemia/Lymphoma; Stage IV Cutaneous T-cell Non-Hodgkin Lymphoma; Stage IV Grade 1 Follicular Lymphoma; Stage IV Grade 2 Follicular Lymphoma; Stage IV Grade 3 Follicular Lymphoma; Stage IV Mantle Cell Lymphoma; Stage IV Marginal Zone Lymphoma; Stage IV Small Lymphocytic Lymphoma; Unspecified Adult Solid Tumor, Protocol Specific

Gemcitabine treatment induces endoplasmic reticular (ER) stress and subsequently upregulates urokinase plasminogen activator (uPA) to block mitochondrial-dependent apoptosis in Panc-1 cancer stem-like cells (CSCs).

PubMed

Wang, Li; Zhang, Yi; Wang, Weiguo; Zhu, Yunjie; Chen, Yang; Tian, Bole

2017-01-01

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with poor survival rates. The presence of cancer stem-like cells (CSCs) is believed to be among the underlying reasons for the aggressiveness of PDAC, which contributes to chemoresistance and recurrence. However, the mechanisms that induce chemoresistance and inhibit apoptosis remain largely unknown. We used serum-free medium to enrich CSCs from panc-1 human pancreatic cancer cells and performed sphere formation testing, flow cytometry, quantitative reverse transcription polymerase chain reaction (RT-qPCR) and semi-quantitative western blotting to confirm the stemness of panc-1 CSCs. Hallmarks of endoplasmic reticulum (ER) stress, including IRE1, PERK, ATF4, ATF6α, GRP78 and uPA expression, were detected after gemcitabine treatment. Effects of gemcitabine-induced uPA expression on cell invasion, sphere formation, colony formation and gemcitabine sensitivity were detected. Electrophoretic mobility shift assays (EMSAs) and RNA-immunoprecipitation (RIP) were performed to detect interaction between the uPA mRNA 3'-UTR and mutant p53-R273H expressed by panc-1 CSCs. The effects of upregulated uPA by gemcitabine on apoptosis were detected by Annexin V-FITC/PI staining, and the impact of uPA on small molecule CP-31398-restored mutant p53 transcriptional activity was measured by a luciferase reporter assay. Enriched panc-1 CSCs expressing high levels of CD44 and CD133 also produced significantly higher amounts of Oct4 and Nanog. Compared with panc-1 cells, panc-1 CSCs presented chemoresistance to gemcitabine. ER stress gene detections demonstrated effects of gemcitabine-induced ER stress on both the pro-apoptotic and pro-survival branches. ER stress-induced ATF6α upregulated level of uPA by transcriptionally activating GRP78. Gemcitabine-induced uPA promoted invasion, sphere formation and colony formation and attenuated apoptosis induced by gemcitabine in panc-1 CSCs, depending on interaction with mutant p53-R273H. Upregulation of uPA abolished CP-31398-mediated restoration of mutant p53 transcriptional activity in panc-1 CSCs. Gemcitabine treatment induced ER stress and promoted mutant p53-R273H stabilization via transcriptionally activated uPA which may contribute to chemoresistance to gemcitabine. Notably, upregulation of uPA by gemcitabine treatment may lead to the failure of CP-31398; thus, a novel strategy for modulating mutant p53 function needs to be developed.

Gemcitabine treatment induces endoplasmic reticular (ER) stress and subsequently upregulates urokinase plasminogen activator (uPA) to block mitochondrial-dependent apoptosis in Panc-1 cancer stem-like cells (CSCs)

PubMed Central

Wang, Weiguo; Zhu, Yunjie; Chen, Yang

2017-01-01

Background Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with poor survival rates. The presence of cancer stem-like cells (CSCs) is believed to be among the underlying reasons for the aggressiveness of PDAC, which contributes to chemoresistance and recurrence. However, the mechanisms that induce chemoresistance and inhibit apoptosis remain largely unknown. Methods We used serum-free medium to enrich CSCs from panc-1 human pancreatic cancer cells and performed sphere formation testing, flow cytometry, quantitative reverse transcription polymerase chain reaction (RT-qPCR) and semi-quantitative western blotting to confirm the stemness of panc-1 CSCs. Hallmarks of endoplasmic reticulum (ER) stress, including IRE1, PERK, ATF4, ATF6α, GRP78 and uPA expression, were detected after gemcitabine treatment. Effects of gemcitabine-induced uPA expression on cell invasion, sphere formation, colony formation and gemcitabine sensitivity were detected. Electrophoretic mobility shift assays (EMSAs) and RNA-immunoprecipitation (RIP) were performed to detect interaction between the uPA mRNA 3’-UTR and mutant p53-R273H expressed by panc-1 CSCs. The effects of upregulated uPA by gemcitabine on apoptosis were detected by Annexin V-FITC/PI staining, and the impact of uPA on small molecule CP-31398-restored mutant p53 transcriptional activity was measured by a luciferase reporter assay. Results Enriched panc-1 CSCs expressing high levels of CD44 and CD133 also produced significantly higher amounts of Oct4 and Nanog. Compared with panc-1 cells, panc-1 CSCs presented chemoresistance to gemcitabine. ER stress gene detections demonstrated effects of gemcitabine-induced ER stress on both the pro-apoptotic and pro-survival branches. ER stress-induced ATF6α upregulated level of uPA by transcriptionally activating GRP78. Gemcitabine-induced uPA promoted invasion, sphere formation and colony formation and attenuated apoptosis induced by gemcitabine in panc-1 CSCs, depending on interaction with mutant p53-R273H. Upregulation of uPA abolished CP-31398-mediated restoration of mutant p53 transcriptional activity in panc-1 CSCs. Conclusion Gemcitabine treatment induced ER stress and promoted mutant p53-R273H stabilization via transcriptionally activated uPA which may contribute to chemoresistance to gemcitabine. Notably, upregulation of uPA by gemcitabine treatment may lead to the failure of CP-31398; thus, a novel strategy for modulating mutant p53 function needs to be developed. PMID:28854261

Membrane Localization of Human Equilibrative Nucleoside Transporter 1 in Tumor Cells May Predict Response to Adjuvant Gemcitabine in Resected Cholangiocarcinoma Patients.

PubMed

Brandi, Giovanni; Deserti, Marzia; Vasuri, Francesco; Farioli, Andrea; Degiovanni, Alessio; Palloni, Andrea; Frega, Giorgio; Barbera, Maria A; de Lorenzo, Stefania; Garajova, Ingrid; Di Marco, Mariacristina; Pinna, Antonio D; Cescon, Matteo; Cucchetti, Alessandro; Ercolani, Giorgio; D'Errico-Grigioni, Antonietta; Pantaleo, Maria A; Biasco, Guido; Tavolari, Simona

2016-05-01

The use of gemcitabine as an adjuvant modality for cholangiocarcinoma (CC) is increasing, but limited data are available on predictive biomarkers of response. Human equilibrative nucleoside transporter 1 (hENT-1) is the major transporter involved in gemcitabine intracellular uptake. This study investigated the putative predictive role of hENT-1 localization in tumor cells of CC patients undergoing treatment with adjuvant gemcitabine. Seventy-one consecutive patients with resected CC receiving adjuvant gemcitabine at our center were retrospectively analyzed by immunohistochemistry for hENT-1 localization in tumor cells. The main outcome measure was disease-free survival (DFS). Hazard ratios (HRs) of relapse and associated 95% confidence intervals (CIs) were obtained from proportional hazards regression models stratified on quintiles of propensity score. Twenty-three (32.4%) cases were negative for hENT-1, 22 (31.0%) were positive in the cytoplasm only, and 26 (36.6%) showed concomitant cytoplasm/membrane staining. Patients with membrane hENT-1 had a longer DFS (HR 0.49, 95% CI 0.24-0.99, p = .046) than those who were negative or positive only in the cytoplasm of tumor cells. Notably, the association between DFS and membrane hENT-1 was dependent on the number of gemcitabine cycles (one to two cycles: HR 0.96, 95% CI 0.34-2.68; three to four cycles: HR 0.99, 95% CI 0.34-2.90; five to six cycles: HR 0.27, 95% CI 0.10-0.77). hENT-1 localization on tumor cell membrane may predict response to adjuvant gemcitabine in CC patients receiving more than four cycles of chemotherapy. Further prospective randomized trials on larger populations are required to confirm these preliminary results, so that optimal gemcitabine-based chemotherapy may be tailored for CC patients in the adjuvant setting. Gemcitabine is becoming an increasingly used adjuvant modality in cholangiocarcinoma (CC), but limited data are available on predictive biomarkers of response. In this study, patients receiving more than four cycles of adjuvant gemcitabine and harboring Human equilibrative nucleoside transporter 1 (hENT-1, the major transporter involved in gemcitabine intracellular uptake) on tumor cell membrane had a longer disease-free survival compared with patients negative or positive for hENT-1 only in the cytoplasm of tumor cells. Overall these results may lay the basis for further prospective randomized trials based on a larger population of patients and may prove useful for tailoring appropriate gemcitabine-based chemotherapy for CC patients in the adjuvant setting. ©AlphaMed Press.

Chronic nicotine inhibits the therapeutic effects of gemcitabine on pancreatic cancer in vitro and in mouse xenografts.

PubMed

Banerjee, Jheelam; Al-Wadei, Hussein A N; Schuller, Hildegard M

2013-03-01

Smoking is an established risk factor for pancreatic cancer and nicotine replacement therapy (NRT) often accompanies chemotherapy. The current study has tested the hypothesis that chronic exposure to low dose nicotine reduces the responsiveness of pancreatic cancer to the leading therapeutic for this cancer, gemcitabine. The effects of chronic nicotine (1 μm/L) on two pancreatic cancer cell lines in vitro and in a xenograft model were assessed by immunoassays, Western blots and cell proliferation assays. Exposure in vitro to nicotine for 7 days inhibited the gemcitabine-induced reduction in viable cells, gemcitabine-induced apoptosis as indicated by reduced expression of cleaved caspase-3 while inducing the phosphorylation of signalling proteins extracellular signal-regulated kinase (ERK), v-akt thymoma viral oncogene homolog (protein kinase B, AKT) and Src. Nicotine (1 μm/L) in the drinking water for 4 weeks significantly reduced the therapeutic response of mouse xenografts to gemcitabine while reducing the induction of cleaved caspase-3 and the inhibition of phosphorylated forms of multiple signalling proteins by gemcitabine in xenograft tissues. Our experimental data suggest that continued moderate smoking and NRT may negatively impact therapeutic outcomes of gemcitabine on pancreatic cancer and that clinical studies in cancer patients are now warranted. Copyright © 2012 Elsevier Ltd. All rights reserved.

Docetaxel and gemcitabine combination therapy in advanced transitional cell carcinoma of the urothelium: results of a phase II and pharmacologic study.

PubMed

Dumez, Herlinde; Martens, Marc; Selleslach, Johan; Guetens, Gunter; De Boeck, Gert; Aerts, Rita; De Bruijn, Ernst A; Maes, Robert A; van Oosterom, Allan T

2007-02-01

Our objective was to determine the response to gemcitabine plus docetaxel in advanced urothelial transitional cell carcinoma in a phase II trial, and gemcitabine distribution between plasma and erythrocytes, following docetaxel administration. Patients with locally advanced or metastatic transitional cell carcinoma, following a maximum of one prior chemotherapy regimen, were given gemcitabine 800 mg/m on days 1 and 8 plus docetaxel 85 mg/m on day 8, every 21 days. Gemcitabine was measured in the plasma and erythrocytes of nine patients before and after docetaxel administration. Thirty-four patients (median 63 years; range 49-79 years), of whom seven had prior chemotherapy and 27 were chemotherapy-naive, received a median of six cycles (range 1-6). Complete and partial remissions were observed in two and 16 (including three pretreated) patients, respectively, for an overall response rate of 53%. Median response duration was 5 months (range 1-39+). Haematoxicity was manageable, despite grade 3 infections in 24% of patients, but other toxicities were mostly mild. An apparent shift of gemcitabine from plasma to erythrocytes occurred after docetaxel in five of six patients evaluable for this analysis. We conclude gemcitabine plus docetaxel is tolerable and highly active in treated and untreated patients with advanced transitional cell carcinoma.

Effect of midkine on gemcitabine resistance in biliary tract cancer

PubMed Central

Guo, Huihui; Qiu, Li; Sun, Xinrong; Wang, Xiang; Shi, Qian

2018-01-01

Gemcitabine-based chemotherapy is one of the most effective and commonly used chemotherapeutic regimens for biliary tract cancer (BTC). However, development of resistance to this drug limits its efficacy. The present study aimed to explore the effects of midkine (MDK) on the resistance of BTC cells to gemcitabine. Cell viability and proliferation were measured by a Cell Counting Kit-8 assay and 5-ethynyl-2′-deoxyuridine staining, respectively. Western blot analysis was used to detect the expression of E-cadherin and vimentin. The results indicated that BTC cell lines were more resistant to gemcitabine plus MDK compared with gemcitabine alone. In terms of the underlying mechanism, MDK promoted the epithelial to mesenchymal transition (EMT) of BTC cells and the enhancing effect of MDK on gemcitabine resistance was abrogated when the EMT was blocked with small interfering (si)RNA targeting Twist. In addition, MDK promoted the expression of Notch-1, while knockdown of Notch-1 by siRNA blocked the EMT process in the BTC cell lines. Taken together, these results indicated that MDK promoted gemcitabine resistance of BTC through inducing EMT via upregulating Notch-1. It was suggested that inhibition of the EMT is a promising strategy to overcome MDK-induced drug resistance. PMID:29344648

Development and In Vitro Characterization of a Gemcitabine-loaded MUC4-targeted Immunoliposome Against Pancreatic Ductal Adenocarcinoma.

PubMed

Urey, Carlos; Hilmersson, Katarzyma Said; Andersson, Bodil; Ansari, Daniel; Andersson, Roland

2017-11-01

Pancreatic Ductal adeno-carcinoma (PDAC) is a devastating disease. Gemcitabine is the standard chemotherapeutic agent against PDAC but has only limited effectiveness. The aim of the study was to develop and study the targeting affinity and in vitro antiproliferative effect of a MUC4-targeted gemcitabine-loaded immuno-liposome for treatment of PDAC. Gemcitabine-loaded immunoliposomes were developed by grafting anti-MUC4 antibodies to the liposomal surface. Targeting affinity was compared in vitro between immunoliposomes and non-targeted liposomes and anti-proliferative effect was compared in vitro between free drug, non-targeted liposomal gemcitabine and MUC4-targeted immunoliposomal gemcitabine on a MUC4-positive pancreatic cancer cell line, Capan-1. Development of a MUC4-targeted immunoliposome was confirmed and characterized by immunoblots and size characterization. The MUC4-targeted immunoliposome showed a significantly higher targeting affinity compared to the non-targeted liposomes and also showed an improved antiproliferative effect compared to free and non-targeted liposomal drug. Successful development and characterization of a MUC4-targeted immunoliposome shows promising results for a targeted treatment and improved retention of gemcitabine for treatment of PDAC. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Enhancement of DNA ligase I level by gemcitabine in human cancer cells.

PubMed

Sun, Daekyu; Urrabaz, Rheanna; Kelly, Susan; Nguyen, Myhanh; Weitman, Steve

2002-04-01

DNA ligase I is an essential enzyme for completing DNA replication and DNA repair by ligating Okazaki fragments and by joining single-strand breaks formed either directly by DNA-damaging agents or indirectly by DNA repair enzymes, respectively. In this study, we examined whether the DNA ligase I level could be modulated in human tumor cell lines by treatment with gemcitabine (2', 2'-difluoro-2'-deoxycytidine), which is a nucleoside analogue of cytidine with proven antitumor activity against a broad spectrum of human cancers in clinical studies. To determine the effect of gemcitabine on DNA ligase I expression, Western blot analysis was used to measure the DNA ligase I levels in MiaPaCa, NGP, and SK-N-BE cells treated with different concentrations of gemcitabine and harvested at different time intervals. Cell cycle analysis was also performed to determine the underlying mechanism of DNA ligase I level enhancement in response to gemcitabine. In addition, other agents that share the same mechanism of action with gemcitabine were used to elucidate further details. When different types of tumor cell lines, including MiaPaCa, NGP, and SK-N-BE, were treated with gemcitabine, the level of DNA ligase I increased severalfold despite significant cell growth inhibition. In contrast, other DNA ligases (III and IV) either remained unchanged or decreased with treatment. Cell cycle analysis showed that arrest in S-phase corresponded to an increase of DNA ligase I levels in gemcitabine treated cells. Other agents, such as 1-beta-D-arabinofuranosylcytosine and hydroxyurea, which partly share mechanisms of action with gemcitabine by targeting DNA polymerases and ribonucleotide reductase, respectively, also caused an increase of DNA ligase I levels. However, 5-fluorouracil, which predominantly targets thymidylate synthase, did not cause an increase of DNA ligase I level. Our results suggest that an arrest of DNA replication caused by gemcitabine treatment through incorporation of gemcitabine triphosphate into replicating DNA and inhibition of ribonucleotide reductase would trigger an increase in DNA ligase I levels in cancer cells. The elevated presence of DNA ligase I in S-phase-arrested cells leads us to speculate that DNA ligase I might have an important role in repairing DNA damage caused by stalled replication forks.

A randomized, placebo-controlled phase III trial of masitinib plus gemcitabine in the treatment of advanced pancreatic cancer

PubMed Central

Deplanque, G.; Demarchi, M.; Hebbar, M.; Flynn, P.; Melichar, B.; Atkins, J.; Nowara, E.; Moyé, L.; Piquemal, D.; Ritter, D.; Dubreuil, P.; Mansfield, C. D.; Acin, Y.; Moussy, A.; Hermine, O.; Hammel, P.

2015-01-01

Background Masitinib is a selective oral tyrosine–kinase inhibitor. The efficacy and safety of masitinib combined with gemcitabine was compared against single-agent gemcitabine in patients with advanced pancreatic ductal adenocarcinoma (PDAC). Patients and methods Patients with inoperable, chemotherapy-naïve, PDAC were randomized (1 : 1) to receive gemcitabine (1000 mg/m2) in combination with either masitinib (9 mg/kg/day) or a placebo. The primary endpoint was overall survival (OS) in the modified intent-to-treat population. Secondary OS analyses aimed to characterize subgroups with poor survival while receiving single-agent gemcitabine with subsequent evaluation of masitinib therapeutic benefit. These prospectively declared subgroups were based on pharmacogenomic data or a baseline characteristic. Results Three hundred and fifty-three patients were randomly assigned to receive either masitinib plus gemcitabine (N = 175) or placebo plus gemcitabine (N = 178). Median OS was similar between treatment-arms for the overall population, at respectively, 7.7 and 7.1 months, with a hazard ratio (HR) of 0.89 (95% CI [0.70; 1.13]. Secondary analyses identified two subgroups having a significantly poor survival rate when receiving single-agent gemcitabine; one defined by an overexpression of acyl–CoA oxidase-1 (ACOX1) in blood, and another via a baseline pain intensity threshold (VAS > 20 mm). These subgroups represent a critical unmet medical need as evidenced from median OS of 5.5 months in patients receiving single-agent gemcitabine, and comprise an estimated 63% of patients. A significant treatment effect was observed in these subgroups for masitinib with median OS of 11.7 months in the ‘ACOX1’ subgroup [HR = 0.23 (0.10; 0.51), P = 0.001], and 8.0 months in the ‘pain’ subgroup [HR = 0.62 (0.43; 0.89), P = 0.012]. Despite an increased toxicity of the combination as compared with single-agent gemcitabine, side-effects remained manageable. Conclusions The present data warrant initiation of a confirmatory study that may support the use of masitinib plus gemcitabine for treatment of PDAC patients with overexpression of ACOX1 or baseline pain (VAS > 20mm). Masitinib's effect in these subgroups is also supported by biological plausibility and evidence of internal clinical validation. Trial Registration ClinicalTrials.gov:NCT00789633. PMID:25858497

A randomized phase II study of weekly nab-paclitaxel plus gemcitabine or simplified LV5FU2 as first-line therapy in patients with metastatic pancreatic cancer: the AFUGEM GERCOR trial.

PubMed

Bachet, Jean-Baptiste; Chibaudel, Benoist; Bonnetain, Franck; Validire, Pierre; Hammel, Pascal; André, Thierry; Louvet, Christophe

2015-10-06

Metastatic pancreatic adenocarcinoma (PAC) prognosis remains dismal and gemcitabine monotherapy has been the standard treatment over the last decade. Currently, two first-line regimens are used in this setting: FOLFIRINOX and nab-paclitaxel plus gemcitabine. Increasing translational data on the predictive value of hENT1 for determining gemcitabine efficacy suggest that a non-gemcitabine-based regimen is favored in about 60 % of patients with PAC due to high resistance of PAC to this cytotoxic drug. This study aims to evaluate the efficacy of weekly nab-paclitaxel combined with gemcitabine or a simplified (s) LV5FU2 regimen in patients with previously untreated metastatic PAC. AFUGEM is a two-stage, open-label, randomized, multicenter, phase II trial. Patients with PAC who meet the inclusion criteria and provide written informed consent will be randomized in a 1:2 ratio to either nab-paclitaxel (125 mg/m(2)) plus gemcitabine (1000 mg/m(2)) given on days 1, 8, and 15 every 28 days or nab-paclitaxel (125 mg/m(2)) plus sLV5FU2 (leucovorin 400 mg/m(2) followed by bolus 400 mg/m(2) 5-fluorouracil and by 5-fluorouracil 2400 mg/m(2) as an 46-h intravenous infusion) given on days 1 and 15 every 28 days. A total of 114 patients will be randomized to one of the treatment arms. The primary endpoint is progression-free survival at 4 months. Secondary outcomes are rate and duration of response, disease control, overall survival, safety, and quality of life. Potential biomarkers of gemcitabine (hENT1, dCK) and 5-fluorouracil (TS) efficacy will be assessed. The AFUGEM trial is designed to provide valuable information regarding efficacy and tolerability of nab-paclitaxel plus gemcitabine and nab-paclitaxel plus sLV5FU2 regimens. Identification of potential predictive biomarkers of gemcitabine and 5-fluorouracil is likely to drive therapeutic decisions in patients with metastatic PAC. AFUGEM is registered at Clinicaltrials.gov: NCT01964534 , October 15, 2013.

Fasting cycles potentiate the efficacy of gemcitabine treatment in in vitro and in vivo pancreatic cancer models

PubMed Central

Mazza, Tommaso; Panebianco, Concetta; Saracino, Chiara; Pereira, Stephen P.; Graziano, Paolo; Pazienza, Valerio

2015-01-01

Background/aims Pancreatic cancer (PC) is ranked as the fourth leading cause of cancer-related deaths worldwide. Despite recent advances in treatment options, a modest impact on the outcome of the disease is observed so far. Short-term fasting cycles have been shown to potentiate the efficacy of chemotherapy against glioma. The aim of this study was to assess the effect of fasting cycles on the efficacy of gemcitabine, a standard treatment for PC patients, in vitro and in an in vivo pancreatic cancer mouse xenograft model. Materials and Methods BxPC-3, MiaPaca-2 and Panc-1 cells were cultured in standard and fasting mimicking culturing condition to evaluate the effects of gemcitabine. Pancreatic cancer xenograft mice were subjected to 24h starvation prior to gemcitabine injection to assess the tumor volume and weight as compared to mice fed ad libitum. Results Fasted pancreatic cancer cells showed increased levels of equilibrative nucleoside transporter (hENT1), the transporter of gemcitabine across the cell membrane, and decreased ribonucleotide reductase M1 (RRM1) levels as compared to those cultured in standard medium. Gemcitabine was more effective in inducing cell death on fasted cells as compared to controls. Consistently, xenograft pancreatic cancer mice subjected to fasting cycles prior to gemcitabine injection displayed a decrease of more than 40% in tumor growth. Conclusion Fasting cycles enhance gemcitabine effect in vitro and in the in vivo PC xenograft mouse model. These results suggest that restrictive dietary interventions could enhance the efficacy of existing cancer treatments in pancreatic cancer patients. PMID:26176887

DNA-PKcs is important for Akt activation and gemcitabine resistance in PANC-1 pancreatic cancer cells.

PubMed

Hu, Hao; Gu, Yuanlong; Qian, Yi; Hu, Benshun; Zhu, Congyuan; Wang, Gaohe; Li, Jianping

2014-09-12

Pancreatic cancer is one of the most aggressive human malignancies with extremely poor prognosis. The moderate activity of the current standard gemcitabine and gemcitabine-based regimens was due to pre-existing or acquired chemo-resistance of pancreatic cancer cells. In this study, we explored the potential role of DNA-dependent protein kinase catalytic subunit (DNA-PKcs) in gemcitabine resistance, and studied the underlying mechanisms. We found that NU-7026 and NU-7441, two DNA-PKcs inhibitors, enhanced gemcitabine-induced cytotoxicity and apoptosis in PANC-1 pancreatic cancer cells. Meanwhile, PANC-1 cells with siRNA-knockdown of DNA-PKcs were more sensitive to gemcitabine than control PANC-1 cells. Through the co-immunoprecipitation (Co-IP) assay, we found that DNA-PKcs formed a complex with SIN1, the latter is an indispensable component of mammalian target of rapamycin (mTOR) complex 2 (mTORC2). DNA-PKcs-SIN1 complexation was required for Akt activation in PANC-1 cells, while inhibition of this complex by siRNA knockdown of DNA-PKcs/SIN1, or by DNA-PKcs inhibitors, prevented Akt phosphorylation in PANC-1 cells. Further, SIN1 siRNA-knockdown also facilitated gemcitabine-induced apoptosis in PANC-1 cells. Finally, DNA-PKcs and p-Akt expression was significantly higher in human pancreatic cancer tissues than surrounding normal tissues. Together, these results show that DNA-PKcs is important for Akt activation and gemcitabine resistance in PANC-1 pancreatic cancer cells. Copyright © 2014 Elsevier Inc. All rights reserved.

Aerosol gemcitabine: preclinical safety and in vivo antitumor activity in osteosarcoma-bearing dogs.

PubMed

Rodriguez, Carlos O; Crabbs, Torrie A; Wilson, Dennis W; Cannan, Virginia A; Skorupski, Katherine A; Gordon, Nancy; Koshkina, Nadya; Kleinerman, Eugenie; Anderson, Peter M

2010-08-01

Osteosarcoma is the most common skeletal malignancy in the dog and in young humans. Although chemotherapy improves survival time, death continues to be attributed to metastases. Aerosol delivery can provide a strategy with which to improve the lung drug delivery while reducing systemic toxicity. The purpose of this study is to assess the safety of a regional aerosol approach to chemotherapy delivery in osteosarcoma-bearing dogs, and second, to evaluate the effect of gemcitabine on Fas expression in the pulmonary metastasis. We examined the systemic and local effects of aerosol gemcitabine on lung and pulmonary metastasis in this relevant large-animal tumor model using serial laboratory and arterial blood gas analysis and histopathology and immunohistochemistry, respectively. Six hundred seventy-two 1-h doses of aerosol gemcitabine were delivered. The treatment was well tolerated by these subjects with osteosarcoma (n = 20). Aerosol-treated subjects had metastatic foci that demonstrated extensive, predominately central, intratumoral necrosis. Fas expression was decreased in pulmonary metastases compared to the primary tumor (p = 0.008). After aerosol gemcitabine Fas expression in the metastatic foci was increased compared to lung metastases before treatment (p = 0.0075), and even was higher than the primary tumor (p = 0.025). Increased apoptosis (TUNEL) staining was also detected in aerosol gemcitabine treated metastasis compared to untreated controls (p = 0.028). The results from this pivotal translational study support the concept that aerosol gemcitabine may be useful against pulmonary metastases of osteosarcoma. Additional studies that evaluate the aerosol route of administration of gemcitabine in humans should be safe and are warranted.

Gemcitabine enhances cell invasion via activating HAb18G/CD147-EGFR-pSTAT3 signaling.

PubMed

Xu, Bao-Qing; Fu, Zhi-Guang; Meng, Yao; Wu, Xiao-Qing; Wu, Bo; Xu, Liang; Jiang, Jian-Li; Li, Ling; Chen, Zhi-Nan

2016-09-20

Pancreatic cancer, one of the most lethal cancers, has very poor 5-year survival partly due to gemcitabine resistance. Recently, it was reported that chemotherapeutic agents may act as stressors to induce adaptive responses and to promote chemoresistance in cancer cells. During long-term drug treatment, the minority of cancer cells survive and acquire an epithelial-mesenchymal transition phenotype with increased chemo-resistance and metastasis. However, the short-term response of most cancer cells remains unclear. This study aimed to investigate the short-term response of pancreatic cancer cells to gemcitabine stress and to explore the corresponding mechanism. Our results showed that gemcitabine treatment for 24 hours enhanced pancreatic cancer cell invasion. In gemcitabine-treated cells, HAb18G/CD147 was up-regulated; and HAb18G/CD147 down-regulation or inhibition attenuated gemcitabine-enhanced invasion. Mechanistically, HAb18G/CD147 promoted gemcitabine-enhanced invasion by activating the EGFR (epidermal growth factor receptor)-STAT3 (signal transducer and activator of transcription 3) signaling pathway. Inhibition of EGFR-STAT3 signaling counteracted gemcitabine-enhanced invasion, and which relied on HAb18G/CD147 levels. In pancreatic cancer tissues, EGFR was highly expressed and positively correlated with HAb18G/CD147. These data indicate that pancreatic cancer cells enhance cell invasion via activating HAb18G/CD147-EGFR-pSTAT3 signaling. Our findings suggest that inhibiting HAb18G/CD147 is a potential strategy for overcoming drug stress-associated resistance in pancreatic cancer.

Toxic effects and antitumor response of gemcitabine in combination with piroxicam treatment in dogs with transitional cell carcinoma of the urinary bladder.

PubMed

Marconato, Laura; Zini, Eric; Lindner, Donna; Suslak-Brown, Lisa; Nelson, Victoria; Jeglum, Ann K

2011-04-15

To investigate whether combined treatment with gemcitabine and piroxicam in dogs with transitional cell carcinoma (TCC) of the urinary bladder is tolerated and provides an advantage in terms of survival time over previously reported treatments. Clinical trial. Animals-38 dogs with TCC of the urinary bladder. Dogs were treated with gemcitabine (800 mg/m(2), IV over 30 to 60 minutes, q 7 d) and piroxicam (0.3 mg/kg [0.14 mg/lb], PO, q 24 h). Complete blood cell counts were monitored prior to each gemcitabine treatment. All toxic effects of gemcitabine in dogs were recorded. Primary tumors were ultrasonographically reevaluated after 4 gemcitabine treatments. Dogs received a median of 8 gemcitabine treatments (range, 1 to 38 treatments/dog). In response to treatment, 10 of 38 (26.3%) dogs had grade 1 gastrointestinal tract signs, 11 (28.9%) had grade 2, and 5 (13.2%) had grade 3. Grade 1 neutropenia developed in 6 (15.8%) dogs and grade 2 and 3 neutropenia in 2 (5.3%) dogs each. Thrombocytopenia was rare. All dogs had improvement of clinical signs of disease. Two dogs had a complete tumor response, 8 had a partial response, 19 had stable disease, and 8 had progressive disease. Median survival time with treatment was 230 days. Administration of gemcitabine in combination with piroxicam treatment failed to provide a longer overall survival time in dogs with TCC of the urinary bladder, compared with previously reported treatment strategies. However, this combination of chemotherapy did provide a new treatment alternative with fewer adverse effects.

BRCA2 and RAD51 promote double-strand break formation and cell death in response to gemcitabine.

PubMed

Jones, Rebecca M; Kotsantis, Panagiotis; Stewart, Grant S; Groth, Petra; Petermann, Eva

2014-10-01

Replication inhibitors cause replication fork stalling and double-strand breaks (DSB) that result from processing of stalled forks. During recovery from replication blocks, the homologous recombination (HR) factor RAD51 mediates fork restart and DSB repair. HR defects therefore sensitize cells to replication inhibitors, with clear implications for cancer therapy. Gemcitabine is a potent replication inhibitor used to treat cancers with mutations in HR genes such as BRCA2. Here, we investigate why, paradoxically, mutations in HR genes protect cells from killing by gemcitabine. Using DNA replication and DNA damage assays in mammalian cells, we show that even short gemcitabine treatments cause persistent replication inhibition. BRCA2 and RAD51 are recruited to chromatin early after removal of the drug, actively inhibit replication fork progression, and promote the formation of MUS81- and XPF-dependent DSBs that remain unrepaired. Our data suggest that HR intermediates formed at gemcitabine-stalled forks are converted into DSBs and thus contribute to gemcitabine-induced cell death, which could have implications for the treatment response of HR-deficient tumors. ©2014 American Association for Cancer Research.

BRCA2 and RAD51 promote double-strand break formation and cell death in response to Gemcitabine

PubMed Central

Jones, Rebecca M.; Kotsantis, Panagiotis; Stewart, Grant S.; Groth, Petra; Petermann, Eva

2014-01-01

Replication inhibitors cause replication fork stalling and double-strand breaks (DSBs) that result from processing of stalled forks. During recovery from replication blocks, the homologous recombination (HR) factor RAD51 mediates fork restart and DSB repair. HR defects therefore sensitise cells to replication inhibitors, with clear implications for cancer therapy. Gemcitabine is a potent replication inhibitor used to treat cancers with mutations in HR genes such as BRCA2. Here we investigate why, paradoxically, mutations in HR genes protect cells from killing by Gemcitabine. Using DNA replication and -damage assays in mammalian cells, we show that even short Gemcitabine treatments cause persistent replication inhibition. BRCA2 and RAD51 are recruited to chromatin early after removal of the drug, actively inhibit replication fork progression and promote the formation of MUS81- and XPF-dependent DSBs that remain unrepaired. Our data suggest that HR intermediates formed at Gemcitabine-stalled forks are converted into DSBs and thus contribute to Gemcitabine-induced cell death, which could have implications for the treatment response of HR-deficient tumours. PMID:25053826

Therapy of pancreatic cancer via an EphA2 receptor-targeted delivery of gemcitabine

PubMed Central

Barile, Elisa; Das, Swadesh K.; Emdad, Luni; Sarkar, Devanand; De, Surya K.; Kharagh, Susan Morvaridi; Stebbins, John L.; Pandol, Stephen J.; Fisher, Paul B.; Pellecchia, Maurizio

2016-01-01

First line treatment for pancreatic cancer consists of surgical resection, if possible, and a subsequent course of chemotherapy using the nucleoside analogue gemcitabine. In some patients, an active transport mechanism allows gemcitabine to enter efficiently into the tumor cells, resulting in a significant clinical benefit. However, in most patients, low expression of gemcitabine transporters limits the efficacy of the drug to marginal levels, and patients need frequent administration of the drug at high doses, significantly increasing systemic drug toxicity. In this article we focus on a novel targeted delivery approach for gemcitabine consisting of conjugating the drug with an EphA2 targeting agent. We show that the EphA2 receptor is highly expressed in pancreatic cancers, and accordingly, the drug-conjugate is more effective than gemcitabine alone in targeting pancreatic tumors. Our preliminary observations suggest that this approach may provide a general benefit to pancreatic cancer patients and offers a comprehensive strategy for enhancing delivery of diverse therapeutic agents to a wide range of cancers overexpressing EphA2, thereby potentially reducing toxicity while enhancing therapeutic efficacy. PMID:26959746

Pneumocystis jirovecii pneumonia associated with gemcitabine chemotherapy: experience at an Australian center and recommendations for targeted prophylaxis.

PubMed

Lingaratnam, Senthil M; Slavin, Monica A; Thursky, Karin A; Teh, Benjamin W; Haeusler, Gabrielle M; Seymour, John F; Rischin, Danny; Worth, Leon J

2015-01-01

Pneumocystis jirovecii pneumonia (PJP) is seen increasingly in non-human immunodeficiency virus (HIV) infected immunocompromised populations, but few cases have previously been reported in association with gemcitabine therapy. We identified all patients administered gemcitabine between March 2009 and December 2012 at the Peter MacCallum Cancer Centre. Cases of PJP were identified using accepted definitions. Overall, 288 gemcitabine-treated patients were identified. Nine cases of PJP were detected, corresponding to an overall rate of 3.1% (95% confidence interval [CI] 1.5-5.7%). PJP was diagnosed during gemcitabine therapy in seven patients, a median of 67 (range 31-109) days from commencement. Among patients with lymphoma, 4/22 developed PJP, corresponding to a rate of 18.2% (95% CI 6.1-38.2%). Fewer infections were associated with breast, lung and gastrointestinal malignancies (1/24 [4.2%], 3/118 [2.5%] and 1/61 [1.6%], respectively). A risk-based tool incorporating concomitant steroid therapy can be applied to target high-risk populations who would benefit from PJP prophylaxis during gemcitabine therapy.

[Digital ischemia in two patients treated with gemcitabine].

PubMed

Viguier, J-B; Solanilla, A; Boulon, C; Constans, J; Conri, C

2010-06-01

A 73-year-old man with an urothelial carcinoma treated with gemcitabine and carboplatinium and an 84-year-old man with a mesothelioma treated with gemcitabine alone developed digital ischemia. In the first patient, the ischemia involved all fingers except the thumbs during the second cycle of treatment. The ischemia developed during the first cycle in the second patient and involved the right major and ring fingers. In the literature, gemcitabine vascular toxicity is probably potentialized by platinium salts. Several nosological entities occur simultaneously. The most widely described involve isolated digital ischemia for doses to the order of 3000mg, and a hemolytic and uremic thrombotic microangiopathy for gemcitabine doses above 10,000mg. The vascular toxicity of platinium salts is not dose-dependent. In these two patients, the clinical course was favorable with interruption of the chemotherapy, treatment by iloprost and aspirin.

Molecular evidence for increased antitumor activity of gemcitabine in combination with a cyclin-dependent kinase inhibitor, P276-00 in pancreatic cancers

PubMed Central

2012-01-01

Background P276-00 is a novel cyclin-dependent kinase inhibitor currently in Phase II clinical trials. Gemcitabine is a standard of care for the treatment of pancreatic cancer. The present study investigated the effect of the combination of P276-00 and gemcitabine in five pancreatic cancer cell lines. Methods Cytotoxic activity was evaluated by Propidium Iodide assay. Cell cycle and apoptosis was analyzed by flow cytometry. Genes and proteins known to inhibit apoptosis and contribute to chemoresistance were analysed using western blot analysis and RT-PCR. In vivo efficacy was studied in PANC-1 xenograft model. Results The combination of gemcitabine followed by P276-00 was found to be highly to weakly synergistic in various pancreatic cancer cell lines as assessed by the combination index. Enhancement of apoptosis in PANC-1 cells and decrease in the antiapoptotic protein Bcl-2 and survivin was seen. P276-00 potentiated the gemcitabine-induced cytotoxicity by modulation of proteins involved in chemoresistance to gemcitabine and cell cycle viz. antiapoptotic proteins p8 and cox-2, proapoptotic protein BNIP3 and cell cycle related proteins Cdk4 and cyclin D1. The above results could explain the novel mechanisms of action of the combination therapy. We also show here that gemcitabine in combination with P276-00 is much more effective as an antitumor agent compared with either agent alone in the PANC-1 xenograft tumor model in SCID mice. Conclusions The chemosensitzation of pancreatic tumors to gemcitabine would likely be an important and novel strategy for treatment of pancreatic cancer and enable the use of lower and safer concentrations, to pave the way for a more effective treatment in this devastating disease. Phase IIb clinical trials of P276-00 in combination with gemcitabine in pancreatic cancer patients are ongoing. PMID:22873289

Gemcitabine sensitizes lung cancer cells to Fas/FasL system-mediated killing

PubMed Central

Siena, Liboria; Pace, Elisabetta; Ferraro, Maria; Di Sano, Caterina; Melis, Mario; Profita, Mirella; Spatafora, Mario; Gjomarkaj, Mark

2014-01-01

Gemcitabine is a chemotherapy agent commonly used in the treatment of non-small cell lung cancer (NSCLC) that has been demonstrated to induce apoptosis in NSCLC cells by increasing functionally active Fas expression. The aim of this study was to evaluate the Fas/Fas ligand (FasL) system involvement in gemcitabine-induced lung cancer cell killing. NSCLC H292 cells were cultured in the presence or absence of gemcitabine. FasL mRNA and protein were evaluated by real-time PCR, and by Western blot and flow cytometry, respectively. Apoptosis of FasL-expressing cells was evaluated by flow cytometry, and caspase-8 and caspase-3 activation by Western blot and a colorimetric assay. Cytotoxicity of lymphokine-activated killer (LAK) cells and malignant pleural fluid lymphocytes against H292 cells was analysed in the presence or absence of the neutralizing anti-Fas ZB4 antibody, by flow cytometry. Gemcitabine increased FasL mRNA and total protein expression, the percentage of H292 cells bearing membrane-bound FasL (mFasL) and of mFasL-positive apoptotic H292 cells, as well as caspase-8 and caspase-3 cleavage. Moreover, gemcitabine increased CH11-induced caspase-8 and caspase-3 cleavage and proteolytic activity. Cytotoxicity of LAK cells and pleural fluid lymphocytes was increased against gemcitabine-treated H292 cells and was partially inhibited by ZB4 antibody. These results demonstrate that gemcitabine: (i) induces up-regulation of FasL in lung cancer cells triggering cell apoptosis via an autocrine/paracrine loop; (ii) induces a Fas-dependent apoptosis mediated by caspase-8 and caspase-3 activation; (iii) enhances the sensitivity of lung cancer cells to cytotoxic activity of LAK cells and malignant pleural fluid lymphocytes, partially via Fas/FasL pathway. Our data strongly suggest an active involvement of the Fas/FasL system in gemcitabine-induced lung cancer cell killing. PMID:24128051

Molecular evidence for increased antitumor activity of gemcitabine in combination with a cyclin-dependent kinase inhibitor, P276-00 in pancreatic cancers.

PubMed

Rathos, Maggie J; Joshi, Kavita; Khanwalkar, Harshal; Manohar, Sonal M; Joshi, Kalpana S

2012-08-08

P276-00 is a novel cyclin-dependent kinase inhibitor currently in Phase II clinical trials. Gemcitabine is a standard of care for the treatment of pancreatic cancer. The present study investigated the effect of the combination of P276-00 and gemcitabine in five pancreatic cancer cell lines. Cytotoxic activity was evaluated by Propidium Iodide assay. Cell cycle and apoptosis was analyzed by flow cytometry. Genes and proteins known to inhibit apoptosis and contribute to chemoresistance were analysed using western blot analysis and RT-PCR. In vivo efficacy was studied in PANC-1 xenograft model. The combination of gemcitabine followed by P276-00 was found to be highly to weakly synergistic in various pancreatic cancer cell lines as assessed by the combination index. Enhancement of apoptosis in PANC-1 cells and decrease in the antiapoptotic protein Bcl-2 and survivin was seen. P276-00 potentiated the gemcitabine-induced cytotoxicity by modulation of proteins involved in chemoresistance to gemcitabine and cell cycle viz. antiapoptotic proteins p8 and cox-2, proapoptotic protein BNIP3 and cell cycle related proteins Cdk4 and cyclin D1. The above results could explain the novel mechanisms of action of the combination therapy. We also show here that gemcitabine in combination with P276-00 is much more effective as an antitumor agent compared with either agent alone in the PANC-1 xenograft tumor model in SCID mice. The chemosensitzation of pancreatic tumors to gemcitabine would likely be an important and novel strategy for treatment of pancreatic cancer and enable the use of lower and safer concentrations, to pave the way for a more effective treatment in this devastating disease. Phase IIb clinical trials of P276-00 in combination with gemcitabine in pancreatic cancer patients are ongoing.

Metuzumab enhanced chemosensitivity and apoptosis in non-small cell lung carcinoma

PubMed Central

Feng, Fei; Wang, Bin; Sun, Xiuxuan; Zhu, Yumeng; Tang, Hao; Nan, Gang; Wang, Lijuan; Wu, Bo; Huhe, Muren; Liu, Shuangshuang; Diao, Tengyue; Hou, Rong; Zhang, Yang; Zhang, Zheng

2017-01-01

ABSTRACT Targeted therapeutics is used as an alternative treatment of non-small cell lung cancer (NSCLC); however, treatment effect is far from being satisfactory, and therefore identification of new targets is needed. We have previously shown that metuzumab inhibit tumor growth in vivo. The present study was performed to investigate the anti-tumor efficacy of metuzumab combined with gemcitabine and cisplatin (GP), paclitaxel and cisplatin (TP) or navelbine and cisplatin (NP) regimens in multiple NSCLC cell lines. Our results demonstrate that, in comparison to single agent metuzumab or GP treated cells, metuzumab combined with GP display inhibitory effects on tumor growth. Furthermore, we found that metuzumab elevated the sensitivity of cell lines to gemcitabine, which was identified by MTT assay. Flow cytometric analysis showed that metuzumab combined with gemcitabine (GEM) treatment led to an obvious G1 arrest and an elevated apoptosis in A549, NCI-H460 and NCI-H520 cells. Western blot analysis also demonstrated a significantly reduced level of cyclin D1, Bcl-2, and an obviously increase level of Bax and full-length caspase-3 in A549, NCI-H460 and NCI-H520 cells treated with metuzumab/gemcitabine combination in comparison with single agent treated cells. In addition, metuzumab/gemcitabine treated A549, NCI-H460 and NCI-H520 cells also demonstrated a significantly increase in deoxycytidine kinase (dCK) protein level compared with single agent metuzumab or gemcitabine treated cells. Xenograft models also demonstrated that this metuzumab/gemcitabine combination led to upregulation of dCK. Taken together, the mechanisms of metuzumab combined with GP repress tumor growth were that the combined treatment significantly inhibited the tumor cell proliferation, apoptosis and cell cycle in vitro and in vivo and at least partially by induction of dCK expression. Our results suggested that metuzumab could significantly enhance chemosensitivity of human NSCLC cells to gemcitabine. Metuzumab/gemcitabine combination treatment may be a potentially useful therapeutic regimen for NSCLC patients. PMID:28055291

Extreme Mountain Ultra-Marathon Leads to Acute but Transient Increase in Cerebral Water Diffusivity and Plasma Biomarkers Levels Changes

PubMed Central

Zanchi, Davide; Viallon, Magalie; Le Goff, Caroline; Millet, Grégoire P.; Giardini, Guido; Croisille, Pierre; Haller, Sven

2017-01-01

Background: Pioneer studies demonstrate the impact of extreme sport load on the human brain, leading to threatening conditions for athlete's health such as cerebral edema. The investigation of brain water diffusivity, allowing the measurement of the intercellular water and the assessment of cerebral edema, can give a great contribution to the investigation of the effects of extreme sports on the brain. We therefore assessed the effect of supra-physiological effort (extreme distance and elevation changes) in mountain ultra-marathons (MUMs) athletes combining for the first time brain magnetic resonance imaging (MRI) and blood parameters. Methods:This longitudinal study included 19 volunteers (44.2 ± 9.5 years) finishing a MUM (330 km, elevation + 24000 m). Quantitative measurements of brain diffusion-weighted images (DWI) were performed at 3 time-points: Before the race, upon arrival and after 48 h. Multiple blood biomarkers were simultaneously investigated. Data analyses included brain apparent diffusion coefficient (ADC) and physiological data comparisons between three time-points. Results:The whole brain ADC significantly increased from baseline to arrival (p = 0.005) and then significantly decreased at recovery (p = 0.005) to lower values than at baseline (p = 0.005). While sodium, potassium, calcium, and chloride as well as hematocrit (HCT) changed over time, the serum osmolality remained constant. Significant correlations were found between whole brain ADC changes and osmolality (p = 0.01), cholesterol (p = 0.009), c-reactive protein (p = 0.04), sodium (p = 0.01), and chloride (p = 0.002) plasma level variations. Conclusions:These results suggest the relative increase of the inter-cellular volume upon arrival, and subsequently its reduction to lower values than at baseline, indicating that even after 48 h the brain has not fully recovered to its equilibrium state. Even though serum electrolytes may only indirectly indicate modifications at the brain level due to the blood brain barrier, the results concerning osmolality suggest that body water might directly influence the change in cerebral ADC. These findings establish therefore a direct link between general brain inter-cellular water content and physiological biomarkers modifications produced by extreme sport. PMID:28105018

Extreme Mountain Ultra-Marathon Leads to Acute but Transient Increase in Cerebral Water Diffusivity and Plasma Biomarkers Levels Changes.

PubMed

Zanchi, Davide; Viallon, Magalie; Le Goff, Caroline; Millet, Grégoire P; Giardini, Guido; Croisille, Pierre; Haller, Sven

2016-01-01

Background: Pioneer studies demonstrate the impact of extreme sport load on the human brain, leading to threatening conditions for athlete's health such as cerebral edema. The investigation of brain water diffusivity, allowing the measurement of the intercellular water and the assessment of cerebral edema, can give a great contribution to the investigation of the effects of extreme sports on the brain. We therefore assessed the effect of supra-physiological effort (extreme distance and elevation changes) in mountain ultra-marathons (MUMs) athletes combining for the first time brain magnetic resonance imaging (MRI) and blood parameters. Methods: This longitudinal study included 19 volunteers (44.2 ± 9.5 years) finishing a MUM (330 km, elevation + 24000 m). Quantitative measurements of brain diffusion-weighted images (DWI) were performed at 3 time-points: Before the race, upon arrival and after 48 h. Multiple blood biomarkers were simultaneously investigated. Data analyses included brain apparent diffusion coefficient (ADC) and physiological data comparisons between three time-points. Results: The whole brain ADC significantly increased from baseline to arrival ( p = 0.005) and then significantly decreased at recovery ( p = 0.005) to lower values than at baseline ( p = 0.005). While sodium, potassium, calcium, and chloride as well as hematocrit (HCT) changed over time, the serum osmolality remained constant. Significant correlations were found between whole brain ADC changes and osmolality ( p = 0.01), cholesterol ( p = 0.009), c-reactive protein ( p = 0.04), sodium ( p = 0.01), and chloride ( p = 0.002) plasma level variations. Conclusions: These results suggest the relative increase of the inter-cellular volume upon arrival, and subsequently its reduction to lower values than at baseline, indicating that even after 48 h the brain has not fully recovered to its equilibrium state. Even though serum electrolytes may only indirectly indicate modifications at the brain level due to the blood brain barrier, the results concerning osmolality suggest that body water might directly influence the change in cerebral ADC. These findings establish therefore a direct link between general brain inter-cellular water content and physiological biomarkers modifications produced by extreme sport.

Membrane Localization of Human Equilibrative Nucleoside Transporter 1 in Tumor Cells May Predict Response to Adjuvant Gemcitabine in Resected Cholangiocarcinoma Patients

PubMed Central

Deserti, Marzia; Vasuri, Francesco; Farioli, Andrea; Degiovanni, Alessio; Palloni, Andrea; Frega, Giorgio; Barbera, Maria A.; de Lorenzo, Stefania; Garajova, Ingrid; Di Marco, Mariacristina; Pinna, Antonio D.; Cescon, Matteo; Cucchetti, Alessandro; Ercolani, Giorgio; D’Errico-Grigioni, Antonietta; Pantaleo, Maria A.; Biasco, Guido; Tavolari, Simona

2016-01-01

Background. The use of gemcitabine as an adjuvant modality for cholangiocarcinoma (CC) is increasing, but limited data are available on predictive biomarkers of response. Human equilibrative nucleoside transporter 1 (hENT-1) is the major transporter involved in gemcitabine intracellular uptake. This study investigated the putative predictive role of hENT-1 localization in tumor cells of CC patients undergoing treatment with adjuvant gemcitabine. Methods. Seventy-one consecutive patients with resected CC receiving adjuvant gemcitabine at our center were retrospectively analyzed by immunohistochemistry for hENT-1 localization in tumor cells. The main outcome measure was disease-free survival (DFS). Hazard ratios (HRs) of relapse and associated 95% confidence intervals (CIs) were obtained from proportional hazards regression models stratified on quintiles of propensity score. Results. Twenty-three (32.4%) cases were negative for hENT-1, 22 (31.0%) were positive in the cytoplasm only, and 26 (36.6%) showed concomitant cytoplasm/membrane staining. Patients with membrane hENT-1 had a longer DFS (HR 0.49, 95% CI 0.24–0.99, p = .046) than those who were negative or positive only in the cytoplasm of tumor cells. Notably, the association between DFS and membrane hENT-1 was dependent on the number of gemcitabine cycles (one to two cycles: HR 0.96, 95% CI 0.34–2.68; three to four cycles: HR 0.99, 95% CI 0.34–2.90; five to six cycles: HR 0.27, 95% CI 0.10–0.77). Conclusion. hENT-1 localization on tumor cell membrane may predict response to adjuvant gemcitabine in CC patients receiving more than four cycles of chemotherapy. Further prospective randomized trials on larger populations are required to confirm these preliminary results, so that optimal gemcitabine-based chemotherapy may be tailored for CC patients in the adjuvant setting. Implications for Practice: Gemcitabine is becoming an increasingly used adjuvant modality in cholangiocarcinoma (CC), but limited data are available on predictive biomarkers of response. In this study, patients receiving more than four cycles of adjuvant gemcitabine and harboring Human equilibrative nucleoside transporter 1 (hENT-1, the major transporter involved in gemcitabine intracellular uptake) on tumor cell membrane had a longer disease-free survival compared with patients negative or positive for hENT-1 only in the cytoplasm of tumor cells. Overall these results may lay the basis for further prospective randomized trials based on a larger population of patients and may prove useful for tailoring appropriate gemcitabine-based chemotherapy for CC patients in the adjuvant setting. PMID:27032872

Combination of gemcitabine and erlotinib inhibits recurrent pancreatic cancer growth in mice via the JAK-STAT pathway

PubMed Central

Chen, Liwen; Zhou, Ding'An; Liu, Zhehao; Huang, Xinhao; Liu, Qianfan; Kang, Yiping; Chen, Zili; Guo, Yuntao; Zhu, Haitao; Sun, Chengyi

2018-01-01

Compared to single gemcitabine treatment, the combination of gemcitabine and erlotinib has shown effective response in patients with locally advanced or metastatic pancreatic cancer. However, the combination therapy has not proven effective in patients with pancreatic cancer after R0 or R1 resection. In the present study, a nude mice model of orthotopic xenotransplantation after tumor resection was established using pancreatic cancer cell lines, BxPC-3 and PANC-1. Mice were divided in four groups (each with n=12) and were treated as follows: the control group received a placebo via intraperitoneal injection (i.p.), while the other three groups were treated with gemcitabine (50 mg/kg i.p., twice a week), erlotinib (50 mg/kg oral gavage, once every three days), and combined treatment of gemcitabine and erlotinib, respectively. The treatment lasted for 21 days, after which all mice were sacrificed and tumors were examined ex vivo. We determined that the combination of gemcitabine and erlotinib inhibited recurrent tumor growth and induced apoptosis in vivo by downregulating phosphorylation levels of JAKs and STATs, which in turn downregulated the downstream proteins HIF-1α and cyclin D1, and upregulated caspase-9 and caspase-3 expression. To sum up, the combination of gemcitabine with erlotinib was effective in treating patients with pancreatic cancer after R0 or R1 resection. PMID:29328487

Combination of carbon ion beam and gemcitabine causes irreparable DNA damage and death of radioresistant pancreatic cancer stem-like cells in vitro and in vivo

PubMed Central

Sai, Sei; Wakai, Toshifumi; Vares, Guillaume; Yamada, Shigeru; Kamijo, Takehiko; Kamada, Tadashi; Shirai, Toshiyuki

2015-01-01

We try to elucidate whether a carbon ion beam alone or in combination with gemcitabine has advantages over X-ray in targeting putative pancreatic cancer stem-like cells (CSCs) in vitro and in vivo. Colony, spheroid formation and tumorigenicity assays confirmed that CD44+/ESA+ cells sorted from PANC1 and PK45 cells have more CSC properties than CD44−/ESA− cells. The number of colonies and spheroids formed from CSCs after carbon ion beam irradiation was significantly reduced compared to after X-ray irradiation, and they were extremely highly suppressed when carbon ion beam combined with gemcitabine. The relative biological effectiveness (RBE) values for the carbon ion beam relative to X-ray at the D10 levels for CSCs were 2.23-2.66. Expressions of multiple cell death-related genes were remarkably highly induced, and large numbers of γH2AX foci in CSCs were formed after carbon ion beam combined with gemcitabine. The highly expressed CSC markers were significantly inhibited after 30 Gy of carbon ion beam and almost lost after 25 Gy carbon ion beam combined with 50 mg/kg gemcitabine. In conclusion, a carbon ion beam combined with gemcitabine has superior potential to kill pancreatic CSCs via irreparable clustered DSB compared to a carbon ion alone or X-rays combined with gemcitabine. PMID:25849939

Active Generation and Propagation of Ca2+ Signals within Tunneling Membrane Nanotubes

PubMed Central

Smith, Ian F.; Shuai, Jianwei; Parker, Ian

2011-01-01

A new mechanism of cell-cell communication was recently proposed after the discovery of tunneling nanotubes (TNTs) between cells. TNTs are membrane protrusions with lengths of tens of microns and diameters of a few hundred nanometers that permit the exchange of membrane and cytoplasmic constituents between neighboring cells. TNTs have been reported to mediate intercellular Ca2+ signaling; however, our simulations indicate that passive diffusion of Ca2+ ions alone would be inadequate for efficient transmission between cells. Instead, we observed spontaneous and inositol trisphosphate (IP3)-evoked Ca2+ signals within TNTs between cultured mammalian cells, which sometimes remained localized and in other instances propagated as saltatory waves to evoke Ca2+ signals in a connected cell. Consistent with this, immunostaining showed the presence of both endoplasmic reticulum and IP3 receptors along the TNT. We propose that IP3 receptors may actively propagate intercellular Ca2+ signals along TNTs via Ca2+-induced Ca2+ release, acting as amplification sites to overcome the limitations of passive diffusion in a chemical analog of electrical transmission of action potentials. PMID:21504718

Adjuvant treatment of resectable biliary tract cancer with cisplatin plus gemcitabine: A prospective single center phase II study.

PubMed

Siebenhüner, Alexander R; Seifert, Heike; Bachmann, Helga; Seifert, Burkhardt; Winder, Thomas; Feilchenfeldt, Jonas; Breitenstein, Stefan; Clavien, Pierre-Alain; Stupp, Roger; Knuth, Alexander; Pestalozzi, Bernhard; Samaras, Panagiotis

2018-01-11

Biliary tract cancer (BTC) is a dismal disease, even after curative intent surgery. We conducted this prospective, non-randomized phase II study to evaluate the feasibility and efficacy of cisplatin and gemcitabine as adjuvant treatment in patients with resected BTC. Patients initially received gemcitabine 1000 mg/m 2 alone on days 1, 8 and 15 every 28-days for a total of six cycles (single agent cohort), and after protocol amendment a combination therapy with gemcitabine 1000 mg/m 2 and cisplatin 25 mg/m 2 on days 1 and 8 was administered every 21 days for a total of eight cycles (combined regimen cohort). Treatment was planned to start within eight weeks after curative intent resection. Adverse events, disease-free survival and overall survival were assessed. Overall 30 patients were enrolled in the study from August 2008 and last patient was enrolled at 2nd December 2014. The follow-up of the patients ended at 31st December 2016. The first 9 patients received single-agent gemcitabine. The interim analysis met the predefined feasibility criteria and, from September 2010 on, the second group of 21 patients received the combination of cisplatin plus gemcitabine. In the single-agent cohort with gemcitabine the median relative dose intensity (RDI) was 100% (IQR 88.3-100). Patients treated with the combination cisplatin-gemcitabine received an overall median RDI of 100% (IQR 50-100) for cisplatin and 100% (IQR 75-100) for gemcitabine respectively. The most significant non-hematological adverse events (grade 3 or 4) were fatigue (20%), infections during neutropenia (10%), and two cases of biliary sepsis (7%). Abnormal liver function was seen in 10% of the patients. One patient died due to infectious complications during treatment with cisplatin and gemcitabine. The median disease-free survival (DFS) was 14.9 months (95% CI 0-33.8) with a corresponding 3-year DFS of 43.1 ± 9.1%. The median overall survival (OS) was 40.6 months (95% CI 18.8-62.3) with a 3-year OS of 55.7 ± 9.2%. No statistically significant differences in survival were seen between the two treatment cohorts. Adjuvant chemotherapy with gemcitabine with or without cisplatin was well tolerated and resulted in promising survival of the patients. The study was retrospectively registered on 25th June 2009 at clinicaltrials.gov ( NCT01073839 ).

A phase 1/2 study combining gemcitabine, Pegintron and p53 SLP vaccine in patients with platinum-resistant ovarian cancer.

PubMed

Dijkgraaf, Eveline M; Santegoets, Saskia J A M; Reyners, An K L; Goedemans, Renske; Nijman, Hans W; van Poelgeest, Mariëtte I E; van Erkel, Arien R; Smit, Vincent T H B M; Daemen, Toos A H H; van der Hoeven, Jacobus J M; Melief, Cornelis J M; Welters, Marij J P; Kroep, Judith R; van der Burg, Sjoerd H

2015-10-13

Preclinical tumor models show that chemotherapy has immune modulatory properties which can be exploited in the context of immunotherapy. The purpose of this study was to determine the feasibility and immunogenicity of combinations of such an immunomodulatory chemotherapeutic agent with immunotherapy, p53 synthetic long peptide (SLP) vaccine and Pegintron (IFN-α) in patients with platinum-resistant p53-positive epithelial ovarian cancer (EOC). This is a phase 1/2 trial in which patients sequential 6 cycles of gemcitabine (1000 mg/kg2 iv; n = 3), gemcitabine with Pegintron before and after the first gemcitabine cycle (Pegintron 1 μg/kg sc; n = 6), and gemcitabine and Pegintron combined with p53 SLP vaccine (0.3 mg/peptide, 9 peptides; n = 6). At baseline, 22 days after the 2nd and 6th cycle, blood was collected for immunomonitoring. Toxicity, CA-125, and radiologic response were evaluated after 3 and 6 cycles of chemotherapy. None of the patients enrolled experienced dose-limiting toxicity. Predominant grade 3/4 toxicities were nausea/vomiting and dyspnea. Grade 1/2 toxicities consisted of fatigue (78%) and Pegintron-related flu-like symptoms (72%). Gemcitabine reduced myeloid-derived suppressor cells (p = 0.0005) and increased immune-supportive M1 macrophages (p = 0.04). Combination of gemcitabine and Pegintron stimulated higher frequencies of circulating proliferating CD4+ and CD8+ T-cells but not regulatory T-cells. All vaccinated patients showed strong vaccine-induced p53-specific T-cell responses. Combination of gemcitabine, the immune modulator Pegintron and therapeutic peptide vaccination is a viable approach in the development of combined chemo-immunotherapeutic regimens to treat cancer.

Radiation concurrent with gemcitabine for locally advanced head and neck cancer: a phase I trial and intracellular drug incorporation study.

PubMed

Eisbruch, A; Shewach, D S; Bradford, C R; Littles, J F; Teknos, T N; Chepeha, D B; Marentette, L J; Terrell, J E; Hogikyan, N D; Dawson, L A; Urba, S; Wolf, G T; Lawrence, T S

2001-02-01

To examine the feasibility and dose-limiting toxicity (DLT) of once-weekly gemcitabine at doses predicted in preclinical studies to produce radiosensitization, concurrent with a standard course of radiation for locally advanced head and neck cancer. Tumor incorporation of gemcitabine triphosphate (dFdCTP) was measured to assess whether adequate concentrations were achieved at each dose level. Twenty-nine patients with unresectable head and neck cancer received a course of radiation (70 Gy over 7 weeks, 5 days weekly) concurrent with weekly infusions of low-dose gemcitabine. Tumor biopsies were performed after the first gemcitabine infusion (before radiation started), and the intracellular concentrations of dFdCTP were measured. Severe acute and late mucosal and pharyngeal-related DLT required de-escalation of gemcitabine dose in successive patient cohorts receiving dose levels of 300 mg/m(2)/wk, 150 mg/m(2)/wk, and 50 mg/m(2)/wk. No DLT was observed at 10 mg/m(2)/wk. The rate of endoscopy- and biopsy-assessed complete tumor response was 66% to 87% in the various cohorts. Tumor dFdCTP levels were similar in patients receiving 50 to 300 mg/m(2) (on average, 1.55 pmol/mg, SD 1.15) but were barely or not detectable at 10 mg/m(2). A high rate of acute and late mucosa-related DLT and a high rate of complete tumor response were observed in this regimen at the dose levels of 50 to 300 mg/m(2), which also resulted in similar, subcytotoxic intracellular dFdCTP concentrations. These results demonstrate significant tumor and normal tissue radiosensitization by low-dose gemcitabine. Different regimens of combined radiation and gemcitabine should be evaluated, based on newer preclinical data promising an improved therapeutic ratio.

A phase I study of imexon plus gemcitabine as first-line therapy for advanced pancreatic cancer.

PubMed

Cohen, Steven J; Zalupski, Mark M; Modiano, Manuel R; Conkling, Paul; Patt, Yehuda Z; Davis, Peg; Dorr, Robert T; Boytim, Michelle L; Hersh, Evan M

2010-07-01

Imexon is an aziridine-derived iminopyrrolidone which has synergy with gemcitabine in pancreatic cancer cell lines. Gemcitabine is a standard therapy for pancreatic cancer. We performed a phase I trial of imexon and gemcitabine to evaluate safety, dose-limiting toxicity (DLT), and maximum tolerated dose (MTD) in patients with advanced pancreatic cancer. Patients with untreated locally advanced or metastatic pancreatic adenocarcinoma received therapy in sequential cohorts on regimen A (n = 19; imexon 200 or 280 mg/m(2) intravenously (IV) over 30 min days 1-5, 15-19 and gemcitabine 800 or 1,000 mg/m(2) IV over 30 min on days 1,8,15 every 28 days) or regimen B (n = 86; imexon 280-1,300 mg/m(2) IV over 30-60 min days 1, 8, and 15 and gemcitabine 1,000 mg/m(2) IV over 30 min on days 1, 8, and 15 every 28 days). One hundred five patients received 340 treatment cycles (median 2, range 1-16). median age 63, 61% male, ECOG PS 0/1 50%/50%, 93% metastatic. DLT was abdominal cramping and pain, often with transient, acute diarrhea. Best response was confirmed partial response (PR) in 11.4%, 8.9% unconfirmed PR, and 48.1% with stable disease. There was a dose proportional increase in imexon AUC across the doses tested with terminal half life 69 min at the MTD and no alteration of gemcitabine pharmacokinetics. The recommended phase II dose of imexon is 875 mg/m(2) with gemcitabine 1,000 mg/m(2). DLT was acute abdominal pain and cramping. Encouraging antitumor responses support further evaluation of this combination in advanced pancreatic cancer.

TGF-β-induced stromal CYR61 promotes resistance to gemcitabine in pancreatic ductal adenocarcinoma through downregulation of the nucleoside transporters hENT1 and hCNT3.

PubMed

Hesler, Rachel A; Huang, Jennifer J; Starr, Mark D; Treboschi, Victoria M; Bernanke, Alyssa G; Nixon, Andrew B; McCall, Shannon J; White, Rebekah R; Blobe, Gerard C

2016-11-01

Pancreatic ductal adenocarcinoma (PDAC) is a lethal cancer in part due to inherent resistance to chemotherapy, including the first-line drug gemcitabine. Although low expression of the nucleoside transporters hENT1 and hCNT3 that mediate cellular uptake of gemcitabine has been linked to gemcitabine resistance, the mechanisms regulating their expression in the PDAC tumor microenvironment are largely unknown. Here, we report that the matricellular protein cysteine-rich angiogenic inducer 61 (CYR61) negatively regulates the nucleoside transporters hENT1 and hCNT3. CRISPR/Cas9-mediated knockout of CYR61 increased expression of hENT1 and hCNT3, increased cellular uptake of gemcitabine and sensitized PDAC cells to gemcitabine-induced apoptosis. In PDAC patient samples, expression of hENT1 and hCNT3 negatively correlates with expression of CYR61 . We demonstrate that stromal pancreatic stellate cells (PSCs) are a source of CYR61 within the PDAC tumor microenvironment. Transforming growth factor-β (TGF-β) induces the expression of CYR61 in PSCs through canonical TGF-β-ALK5-Smad2/3 signaling. Activation of TGF-β signaling or expression of CYR61 in PSCs promotes resistance to gemcitabine in PDAC cells in an in vitro co-culture assay. Our results identify CYR61 as a TGF-β-induced stromal-derived factor that regulates gemcitabine sensitivity in PDAC and suggest that targeting CYR61 may improve chemotherapy response in PDAC patients. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Aerosol Gemcitabine: Preclinical Safety and In Vivo Antitumor Activity in Osteosarcoma-Bearing Dogs

PubMed Central

Crabbs, Torrie A.; Wilson, Dennis W.; Cannan, Virginia A.; Skorupski, Katherine A.; Gordon, Nancy; Koshkina, Nadya; Kleinerman, Eugenie; Anderson, Peter M.

2010-01-01

Abstract Background Osteosarcoma is the most common skeletal malignancy in the dog and in young humans. Although chemotherapy improves survival time, death continues to be attributed to metastases. Aerosol delivery can provide a strategy with which to improve the lung drug delivery while reducing systemic toxicity. The purpose of this study is to assess the safety of a regional aerosol approach to chemotherapy delivery in osteosarcoma-bearing dogs, and second, to evaluate the effect of gemcitabine on Fas expression in the pulmonary metastasis. Methods We examined the systemic and local effects of aerosol gemcitabine on lung and pulmonary metastasis in this relevant large-animal tumor model using serial laboratory and arterial blood gas analysis and histopathology and immunohistochemistry, respectively. Results and Conclusions Six hundred seventy-two 1-h doses of aerosol gemcitabine were delivered. The treatment was well tolerated by these subjects with osteosarcoma (n = 20). Aerosol-treated subjects had metastatic foci that demonstrated extensive, predominately central, intratumoral necrosis. Fas expression was decreased in pulmonary metastases compared to the primary tumor (p = 0.008). After aerosol gemcitabine Fas expression in the metastatic foci was increased compared to lung metastases before treatment (p = 0.0075), and even was higher than the primary tumor (p = 0.025). Increased apoptosis (TUNEL) staining was also detected in aerosol gemcitabine treated metastasis compared to untreated controls (p = 0.028). The results from this pivotal translational study support the concept that aerosol gemcitabine may be useful against pulmonary metastases of osteosarcoma. Additional studies that evaluate the aerosol route of administration of gemcitabine in humans should be safe and are warranted. PMID:19803732

Circular RNA Signature Predicts Gemcitabine Resistance of Pancreatic Ductal Adenocarcinoma.

PubMed

Shao, Feng; Huang, Mei; Meng, Futao; Huang, Qiang

2018-01-01

Gemcitabine resistance is currently the main problem of chemotherapy for advanced pancreatic cancer patients. The resistance is thought to be caused by altered drug metabolism or reduced apoptosis of cancer cells. However, the underlying mechanism of Gemcitabine resistance in pancreatic cancer remains unclear. In this study, we established Gemcitabine resistant PANC-1 (PANC-1-GR) cell lines and compared the circular RNAs (circRNAs) profiles between PANC-1 cells and PANC-1-GR cells by RNA sequencing. Differentially expressed circRNAs were demonstrated using scatter plot and cluster heatmap analysis. Gene ontology and pathway analysis were performed to systemically map the genes which are functionally associated to those differentially expressed circRNAs identified from our data. The expression of the differentially expressed circRNAs picked up by RNAseq in PANC-1-GR cells was further validated by qRT-PCR and two circRNAs were eventually identified as the most distinct targets. Consistently, by analyzing plasma samples form pancreatic ductal adenocarcinoma (PDAC) patients, the two circRNAs showed more significant expression in the Gemcitabine non-responsive patients than the responsive ones. In addition, we found that silencing of the two circRNAs could restore the sensitivity of PANC-1-GR cells to Gemcitabine treatment, while over-expression of them could increase the resistance of normal PANC-1 and MIA PACA-2 cells, suggesting that they might serve as drug targets for Gemcitabine resistance. Furthermore, the miRNA interaction networks were also explored based on the correlation analysis of the target microRNAs of these two circRNAs. In conclusion, we successfully established new PANC-1-GR cells, systemically characterized the circRNA and miRNA profiles, and identified two circRNAs as novel biomarkers and potential therapeutic targets for Gemcitabine non-responsive PDAC patients.

Masitinib Combined with Standard Gemcitabine Chemotherapy: In Vitro and In Vivo Studies in Human Pancreatic Tumour Cell Lines and Ectopic Mouse Model

PubMed Central

Humbert, Martine; Castéran, Nathalie; Letard, Sébastien; Hanssens, Katia; Iovanna, Juan; Finetti, Pascal; Bertucci, François; Bader, Thomas; Mansfield, Colin D.; Moussy, Alain; Hermine, Olivier; Dubreuil, Patrice

2010-01-01

Background Tyrosine kinases are attractive targets for pancreatic cancer therapy because several are over-expressed, including PDGFRα/β, FAK, Src and Lyn. A critical role of mast cells in the development of pancreatic cancer has also been reported. Masitinib is a tyrosine kinase inhibitor that selectively targets c-Kit, PDGFRα/β, Lyn, and to a lesser extent the FAK pathway, without inhibiting kinases of known toxicities. Masitinib is particularly efficient in controlling the proliferation, differentiation and degranulation of mast cells. This study evaluates the therapeutic potential of masitinib in pancreatic cancer, as a single agent and in combination with gemcitabine. Methodology/Findings Proof-of-concept studies were performed in vitro on human pancreatic tumour cell lines and then in vivo using a mouse model of human pancreatic cancer. Molecular mechanisms were investigated via gene expression profiling. Masitinib as a single agent had no significant antiproliferative activity while the masitinib/gemcitabine combination showed synergy in vitro on proliferation of gemcitabine-refractory cell lines Mia Paca2 and Panc1, and to a lesser extent in vivo on Mia Paca2 cell tumour growth. Specifically, masitinib at 10 µM strongly sensitised Mia Paca2 cells to gemcitabine (>400-fold reduction in IC50); and moderately sensitised Panc1 cells (10-fold reduction). Transcriptional analysis identified the Wnt/β-catenin signalling pathway as down-regulated in the cell lines resensitised by the masitinib/gemcitabine combination. Conclusions These data establish proof-of-concept that masitinib can sensitise gemcitabine-refractory pancreatic cancer cell lines and warrant further in vivo investigation. Indeed, such an effect has been recently observed in a phase 2 clinical study of patients with pancreatic cancer who received a masitinib/gemcitabine combination. PMID:20209107

Hippo pathway mediates resistance to cytotoxic drugs.

PubMed

Gujral, Taranjit S; Kirschner, Marc W

2017-05-02

Chemotherapy is widely used for cancer treatment, but its effectiveness is limited by drug resistance. Here, we report a mechanism by which cell density activates the Hippo pathway, which in turn inactivates YAP, leading to changes in the regulation of genes that control the intracellular concentrations of gemcitabine and several other US Food and Drug Administration (FDA)-approved oncology drugs. Hippo inactivation sensitizes a diverse panel of cell lines and human tumors to gemcitabine in 3D spheroid, mouse xenografts, and patient-derived xenograft models. Nuclear YAP enhances gemcitabine effectiveness by down-regulating multidrug transporters as well by converting gemcitabine to a less active form, both leading to its increased intracellular availability. Cancer cell lines carrying genetic aberrations that impair the Hippo signaling pathway showed heightened sensitivity to gemcitabine. These findings suggest that "switching off" of the Hippo-YAP pathway could help to prevent or reverse resistance to some cancer therapies.

Suppression of ErbB-2 in androgen-independent human prostate cancer cells enhances cytotoxic effect by gemcitabine in an androgen-reduced environment.

PubMed

Zhang, Li; Davis, Jeffrey S; Zelivianski, Stanislav; Lin, Fen-Fen; Schutte, Rachel; Davis, Thomas L; Hauke, Ralph; Batra, Surinder K; Lin, Ming-Fong

2009-11-18

We examined the efficacy of combination treatments utilizing cytotoxic drugs plus inhibitors to members of the ErbB-ERK signal pathway in human prostate cancer (PCa) LNCaP C-81 cells. Under an androgen-reduced condition, 50nM gemcitabine caused about 40% growth suppression on C-81 cells. Simultaneous treatment of gemcitabine plus 10microM AG825 produced 60% suppression (p<0.03); while, 85% growth inhibition (p<0.02) was seen if AG825 was added to gemcitabine-treated cells after a 24h-interval. Our data thus showed that in androgen-reduced conditions, inhibition of ErbB-2 increases the cytotoxic efficacy of gemcitabine in PCa cells. This finding has significant implications in the choice of drugs for combination therapy as well as the order of administration for treating cancer patients.

[Gemcitabine and non small-cell lung cancer].

PubMed

Vignot, Stéphane; Besse, Benjamin

2007-01-01

Questions raised during gemcitabine development reflect non small-cell lung cancer (NSCLC) history during last 10 years. Third generation therapies (gemcitabine, vinorelbine and taxanes) combined with platinium compounds are now to be prescribed in almost all clinical situations, from surgically removed tumors to metastatic diseases. The 30% response rate usually reported in advanced disease (with a median survival of 10 months) has to be improved and a more global approach is nowadays mandatory, including targeted agents. This review sum-up the clinical situations in which gemcitabine can be prescribed (advanced disease), or shall be prescribed (adjuvant setting, combination with anti-angiogenic agent or EGFR inhibitors), and highlight opening questions.

Fisetin Enhances the Cytotoxicity of Gemcitabine by Down-regulating ERK-MYC in MiaPaca-2 Human Pancreatic Cancer Cells.

PubMed

Kim, Nayoung; Kang, Min-Jung; Lee, Sang Hyub; Son, Jun Hyuk; Lee, Ji Eun; Paik, Woo Hyun; Ryu, Ji Kon; Kim, Yong-Tae

2018-06-01

Pancreatic cancer is a highly lethal malignancy with a poor prognosis. This study was set up to investigate the combined effect of gemcitabine and fisetin, a natural flavonoid from plants, on human pancreatic cancer cells. Meterials and Methods: Cytotoxic effect of fisetin in combination with gemcitabine on MiaPaca-2 cells was evaluated by the MTT assay, caspase 3/7 assay and propidium iodide/Annexin V. Extracellular signal-regulated kinase (ERK)-v-myc avian myelocytomatosis viral oncogene homolog (MYC) pathway was investigated by western blotting and quantitative real-time polymerase chain reaction. Combination treatment with fisetin and gemcitabine inhibited the proliferation of pancreatic cancer cells within 72 h and induced apoptosis, as indicated by activation of caspase 3/7. Fisetin down-regulated ERK at the protein and mRNA levels, and reduced ERK-induced MYC instability at the protein level. Fisetin sensitized human pancreatic cancer cells to gemcitabine-induced cytotoxicity through inhibition of ERK-MYC signaling. These results suggest that the combination of fisetin and gemcitabine could be developed as a novel potent therapeutic. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Diffusion of a Concentrated Lattice Gas in a Regular Comb Structure

NASA Astrophysics Data System (ADS)

Garcia, Paul; Wentworth, Christopher

2008-10-01

Understanding diffusion in constrained geometries is of interest in a variety of contexts as varied as mass transport in disordered solids, such as a percolation cluster, or intercellular transport of water molecules in biological tissue. In this investigation we explore diffusion in a very simple constrained geometry: a comb-like structure involving a one-dimensional backbone of lattice sites with regularly spaced teeth of fixed length. The model considered assumes a fixed concentration of diffusing particles can hop to nearest-neighbor sites only, and they do not interact with each other except that double occupancy is not allowed. The system is simulated using a Monte Carlo simulation procedure. The mean-square displacement of a tagged particle is calculated from the simulation as a function of time. The simulation shows normal diffusive behavior after a period of anomalous diffusion that increases as the tooth size increases.

Clobenpropit enhances anti-tumor effect of gemcitabine in pancreatic cancer

PubMed Central

Paik, Woo Hyun; Ryu, Ji Kon; Jeong, Kyoung-Sin; Park, Jin Myung; Song, Byeong Jun; Lee, Sang Hyub; Kim, Yong-Tae; Yoon, Yong Bum

2014-01-01

AIM: To evaluate the anti-tumor effect of clobenpropit, which is a specific H3 antagonist and H4 agonist, in combination with gemcitabine in a pancreatic cancer cell line. METHODS: Three kinds of human pancreatic cancer cell lines (Panc-1, MiaPaCa-2, and AsPC-1) were used in this study. Expression of H3 and H4 receptors in pancreatic cancer cells was identified with Western blotting. Effects of clobenpropit on cell proliferation, migration and apoptosis were evaluated. Alteration of epithelial and mesenchymal markers after administration of clobenpropit was analyzed. An in vivo study with a Panc-1 xenograft mouse model was also performed. RESULTS: H4 receptors were present as 2 subunits in human pancreatic cancer cells, while there was no expression of H3 receptor. Clobenpropit inhibited cell migration and increased apoptosis of pancreatic cancer cells in combination with gemcitabine. Clobenpropit up-regulated E-cadherin, but down-regulated vimentin and matrix metalloproteinase 9 in real-time polymerase chain reaction. Also, clobenpropit inhibited tumor growth (gemcitabine 294 ± 46 mg vs combination 154 ± 54 mg, P = 0.02) and enhanced apoptosis in combination with gemcitabine (control 2.5%, gemcitabine 25.8%, clobenpropit 9.7% and combination 40.9%, P = 0.001) by up-regulation of E-cadherin and down-regulation of Zeb1 in Panc-1 xenograft mouse. CONCLUSION: Clobenpropit enhanced the anti-tumor effect of gemcitabine in pancreatic cancer cells through inhibition of the epithelial-mesenchymal transition process. PMID:25024609

[Gemcitabine-induced thrombotic microangiopathy: Can we improve screening and treatment?

PubMed

Charmetant, Xavier; Jolivot, Anne; Fournier, Thomas; Puthet, Jean-Charles; Cassier, Philippe; Lemoine, Sandrine; Juillard, Laurent

2017-06-01

Thrombotic microangiopathy is a rare but severe complication of treatment with gemcitabine. Its prevalence increases because gemcitabine's indications are growing. We report four cases, which presented with common clinical and biological manifestations, i.e. high blood pressure, proteinuria and increasing plasmatic creatinine level. However, severity was not similar, hemodialysis was inconstant. There is no consensus on treatment for this condition. Stopping gemcitabine is essential. Treatment was dispensed considering the severity of the presentation: plasma exchange therapy of variable outcome, and eculizumab, which was efficient when used. It's important to note that this syndrome includes common and frequent signs in patients receiving chemotherapies. But they must encourage the research of most specific signs, such as hypertension, mechanic hemolysis signs, proteinuria or hematuria, in order to recognize thrombotic microangiopathy as early as possible to treat it precociously, and to prevent additional gemcitabine injections. Copyright © 2017 Société francophone de néphrologie, dialyse et transplantation. Published by Elsevier Masson SAS. All rights reserved.

Posterior Segment Toxicity Following Gemcitabine and Docetaxel Chemotherapy

PubMed Central

Valeshabad, Ali Kord; Mieler, William F.; Setlur, Vikram; Thomas, Merina; Shahidi, Mahnaz

2015-01-01

Purpose To report outer retinal disruption and uveal effusion following gemcitabine and docetaxel combination therapy. Case Report A 78-year-old woman presented with blurry vision following two cycles of gemcitabine and docetaxel combination chemotherapy for stage IV sarcoma. At presentation, visual acuity (VA) was finger counting and 20/25 in the right and left eyes, respectively. Slit lamp examination and B scan ultrasonography revealed severe uveal effusion in the right eye and choroidal folds in the left eye. Spectral domain optical coherence tomography showed disruption of photoreceptor inner segment ellipsoid band in the right eye. The patient was monitored weekly with ophthalmic examination and B scan ultrasonography, while continuing with gemcitabine monotherapy. At 8 weeks follow up, uveal effusion improved considerably and VA was 20/40 and 20/20 in the right and left eyes, respectively. Conclusions Uveal effusion and outer retinal disruption were reported following gemcitabine and docetaxel chemotherapy. Early detection and close ophthalmic monitoring may allow concurrent cancer treatment and prevention of possible chemotherapy-induced ocular side effects. PMID:25822016

The degradation of the antitumor agent gemcitabine hydrochloride in an acidic aqueous solution at pH 3.2 and identification of degradation products.

PubMed

Jansen, P J; Akers, M J; Amos, R M; Baertschi, S W; Cooke, G G; Dorman, D E; Kemp, C A; Maple, S R; McCune, K A

2000-07-01

A study of the degradation kinetics of gemcitabine hydrochloride (2'-deoxy-2',2'-difluorocytidine) in aqueous solution at pH 3.2 was conducted. The degradation of gemcitabine followed pseudo first-order kinetics, and rate constants were determined at four different temperatures. These rates were used to construct an Arrhenius plot from which degradation rates at lower temperatures were extrapolated and activation energy calculated. Four major degradation products were identified. Only one of these degradation products, the uridine analogue of gemcitabine, was a known degradation product of gemcitabine and was identified by comparison with synthesized material. The other three degradation products were isolated and characterized by spectroscopic techniques. Two of these products were determined to be the diastereomeric 6-hydroxy-5, 6-dihydro-2'-deoxy-2',2'-difluorouridines, and the other product was determined to be O(6),5'-cyclo-5,6-dihydro-2'-deoxy-2', 2'-difluorouridine. The mechanisms of formation of these degradation products are discussed.

Mass spectrometry-based metabolic profiling of gemcitabine-sensitive and gemcitabine-resistant pancreatic cancer cells.

PubMed

Fujimura, Yoshinori; Ikenaga, Naoki; Ohuchida, Kenoki; Setoyama, Daiki; Irie, Miho; Miura, Daisuke; Wariishi, Hiroyuki; Murata, Masaharu; Mizumoto, Kazuhiro; Hashizume, Makoto; Tanaka, Masao

2014-03-01

Gemcitabine resistance (GR) is one of the critical issues for therapy for pancreatic cancer, but the mechanism still remains unclear. Our aim was to increase the understanding of GR by metabolic profiling approach. To establish GR cells, 2 human pancreatic cancer cell lines, SUIT-2 and CAPAN-1, were exposed to increasing concentration of gemcitabine. Both parental and chemoresistant cells obtained by this treatment were subjected to metabolic profiling based on liquid chromatography-mass spectrometry. Multivariate statistical analyses, both principal component analysis and orthogonal partial least squares discriminant analysis, distinguished metabolic signature of responsiveness and resistance to gemcitabine in both SUIT-2 and CAPAN-1 cells. Among significantly different (P < 0.005) metabolite peaks between parental and GR cells, we identified metabolites related to several metabolic pathways such as amino acid, nucleotide, energy, cofactor, and vitamin pathways. Decreases in glutamine and proline levels as well as increases in aspartate, hydroxyproline, creatine, and creatinine levels were observed in chemoresistant cells from both cell lines. These results suggest that metabolic profiling can isolate distinct features of pancreatic cancer in the metabolome of gemcitabine-sensitive and GR cells. These findings may contribute to the biomarker discovery and an enhanced understanding of GR in pancreatic cancer.

A phase II trial of fixed-dosed rate gemcitabine in platinum-resistant ovarian cancer: a GEICO (Grupo Español de Investigación en Cáncer de Ovario) Trial.

PubMed

Ojeda Gonzalez, Belen; Gonzalez Martin, Antonio; Bover Barcelo, Isabel; Fabregat i Mayol, Xavier; Mellado, Begoña; Rubio Perez, María Jesus; Alonso Carrion, Lorenzo; Casado Herraez, Antonio; Calvo Garcia, Elisa; Churruca Galaz, Cristina; Arcusa Lanza, Angels; Herrero Ibañez, Ana; Adrover Cebrian, Encarna; Poveda Velasco, Andres

2008-10-01

Gemcitabine has well-recognized activity in the treatment of ovarian cancer. Fixed-dose rate (FDR) delivery has been proposed as a more rationale way to administer gemcitabine, to avoid saturation of the enzyme that catalyzes its intracellular transformation into the active metabolites, difluorodeoxycitidine biphosphate, and triphosphate. Our aim was to assess clinical activity of gemcitabine delivered by FDR infusion in patients with platinum resistant ovarian cancer. Patients with platinum-resistant ovarian cancer received gemcitabine 1000 mg/m(2) over 120 minutes on days 1 and 8 of each cycle. Cycles were repeated every 3 weeks, and up to 6 cycles were delivered. Forty-eight patients were included in the study. Among 41 patients evaluable for response, 9 clinical responses (1 complete response and 8 partial responses) were observed, achieving a global response rate of 22%. Grade 3 to 4 hematological toxicity consisted of anemia (15% of patients), neutropenia (24%), and thrombopenia (10%). One patient died due to septic shock. The main grade 3 to 4 nonhematological toxicity was asthenia (7 patients, 17%). Activity of gemcitabine administered by FDR infusion in patients with platinum-resistant ovarian cancer seems similar to that achieved using 30-minute infusions, with higher toxicity.

Intercellular signaling via cyclic GMP diffusion through gap junctions restarts meiosis in mouse ovarian follicles.

PubMed

Shuhaibar, Leia C; Egbert, Jeremy R; Norris, Rachael P; Lampe, Paul D; Nikolaev, Viacheslav O; Thunemann, Martin; Wen, Lai; Feil, Robert; Jaffe, Laurinda A

2015-04-28

Meiosis in mammalian oocytes is paused until luteinizing hormone (LH) activates receptors in the mural granulosa cells of the ovarian follicle. Prior work has established the central role of cyclic GMP (cGMP) from the granulosa cells in maintaining meiotic arrest, but it is not clear how binding of LH to receptors that are located up to 10 cell layers away from the oocyte lowers oocyte cGMP and restarts meiosis. Here, by visualizing intercellular trafficking of cGMP in real-time in live follicles from mice expressing a FRET sensor, we show that diffusion of cGMP through gap junctions is responsible not only for maintaining meiotic arrest, but also for rapid transmission of the signal that reinitiates meiosis from the follicle surface to the oocyte. Before LH exposure, the cGMP concentration throughout the follicle is at a uniformly high level of ∼2-4 μM. Then, within 1 min of LH application, cGMP begins to decrease in the peripheral granulosa cells. As a consequence, cGMP from the oocyte diffuses into the sink provided by the large granulosa cell volume, such that by 20 min the cGMP concentration in the follicle is uniformly low, ∼100 nM. The decrease in cGMP in the oocyte relieves the inhibition of the meiotic cell cycle. This direct demonstration that a physiological signal initiated by a stimulus in one region of an intact tissue can travel across many layers of cells via cyclic nucleotide diffusion through gap junctions could provide a general mechanism for diverse cellular processes.

Co-treatment with a C1B5 peptide of protein kinase Cγ and a low dose of gemcitabine strongly attenuated pancreatic cancer growth in mice through T cell activation.

PubMed

Ishiguro, Susumu; Kawabata, Atsushi; Zulbaran-Rojas, Alejandro; Monson, Kelsey; Uppalapati, Deepthi; Ohta, Naomi; Inui, Makoto; Pappas, Charalampos G; Tzakos, Andreas G; Tamura, Masaaki

2018-01-01

Although gemcitabine is an effective chemotherapeutic for pancreatic cancer, severe side effects often accompany its use. Since we have discovered that locally administered C1B domain peptides effectively control tumor growth without any side effects, the efficacy of co-treatment with this peptide and a low dose of gemcitabine on the growth of pancreatic cancer was examined. Two- and three-dimensional cell culture studies clarified that a co-treatment with C1B5 peptide and gemcitabine significantly attenuated growth of PAN02 mouse and PANC-1 human pancreatic cancer cells in 2D and 3D cultures. Although treatment with the low dose of gemcitabine alone (76%) or the C1B5 peptide alone (39%) inhibited tumor growth moderately, a co-treatment with C1B5 peptide and a low dose of gemcitabine markedly inhibited the growth of PAN02 autografts in the mouse peritoneal cavity (94% inhibition) without any noticeable adverse effect. The number of peritoneal cavity-infiltrating neutrophils and granzyme B + lymphocytes was significantly higher in the co-treatment group than in the control group. A significant increase of granzyme B mRNA expression was also detected in human T cells by the co-treatment. Taken together, the current study suggests that C1B5 peptide offers a remarkably effective combination treatment strategy to reduce side effects associated with gemcitabine, without losing its tumoricidal effect. Copyright © 2017 Elsevier Inc. All rights reserved.

Cytotoxicity of gemcitabine enhanced by polyphenolics from Aronia melanocarpa in pancreatic cancer cell line AsPC-1.

PubMed

Thani, Noor Azela Abdullah; Keshavarz, Sholeh; Lwaleed, Bashir A; Cooper, Alan J; Rooprai, Harcharan K

2014-11-01

Extending work with brain tumours, the hypothesis that micronutrients may usefully augment anticancer regimens, chokeberry (Aronia melanocarpa) extract was tested to establish whether it has pro-apoptotic effects in AsPC-1, an established human pancreatic cell line, and whether it potentiates cytotoxicity in combination with gemcitabine. Pancreatic cancer was chosen as a target, as its prognosis remains dismal despite advances in therapy. An MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay was used to assess the growth of the single pancreatic cancer cell line AsPC-1, alone and in comparison or combination with gemcitabine. This was backed up by flow cytometric DRAQ7 cell viability analysis. TUNEL assays were also carried out to investigate pro-apoptotic properties as responsible for the effects of chokeberry extract. Chokeberry extract alone and its IC75 value (1 µg/mL) in combination with gemcitabine were used to assess the growth of the AsPC-1 cell line. Gemcitabine in combination with chokeberry extract was more effective than gemcitabine alone. TUNEL assays showed apoptosis to be a mechanism occurring at 1 µg/mL concentration of chokeberry, with apoptotic bodies detected by both colourimetric and fluorometric methods. The implication of this study, using single cancer cell line, is that chemotherapy (at least with gemcitabine) might be usefully augmented with the use of micronutrients such as chokeberry extract. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The bias of a 2D view: Comparing 2D and 3D mesophyll surface area estimates using non-invasive imaging

USDA-ARS?s Scientific Manuscript database

The surface area of the leaf mesophyll exposed to intercellular airspace per leaf area (Sm) is closely associated with CO2 diffusion and photosynthetic rates. Sm is typically estimated from two-dimensional (2D) leaf sections and corrected for the three-dimensional (3D) geometry of mesophyll cells, l...

The histopathological effect of intracameral ropivacaine in different concentrations on corneal endothelium.

PubMed

Caça, Ihsan; Kavak, Vatan; Unlü, Kaan; Ari, Seyhmus; Nergis, Yusuf; Take, Gülnür

2006-01-01

We evaluated the histopathological changes occurring in corneal endothelium after intracameral injection ropivacaine into rats. Intracamerally administered ropivacaine in 1, 0.5, and 0.1% concentrations resulted in impairment of hexagonal structure of corneal endothelial cells and intercellular junctions, destruction of microvilli on the cell surface, roughness of cell borders, picnotic nucleus, diffuse vacuolization, and crystalysis in mitochondria.

Active generation and propagation of Ca2+ signals within tunneling membrane nanotubes.

PubMed

Smith, Ian F; Shuai, Jianwei; Parker, Ian

2011-04-20

A new mechanism of cell-cell communication was recently proposed after the discovery of tunneling nanotubes (TNTs) between cells. TNTs are membrane protrusions with lengths of tens of microns and diameters of a few hundred nanometers that permit the exchange of membrane and cytoplasmic constituents between neighboring cells. TNTs have been reported to mediate intercellular Ca(2+) signaling; however, our simulations indicate that passive diffusion of Ca(2+) ions alone would be inadequate for efficient transmission between cells. Instead, we observed spontaneous and inositol trisphosphate (IP(3))-evoked Ca(2+) signals within TNTs between cultured mammalian cells, which sometimes remained localized and in other instances propagated as saltatory waves to evoke Ca(2+) signals in a connected cell. Consistent with this, immunostaining showed the presence of both endoplasmic reticulum and IP(3) receptors along the TNT. We propose that IP(3) receptors may actively propagate intercellular Ca(2+) signals along TNTs via Ca(2+)-induced Ca(2+) release, acting as amplification sites to overcome the limitations of passive diffusion in a chemical analog of electrical transmission of action potentials. Copyright © 2011 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Ursolic acid inhibits the growth of human pancreatic cancer and enhances the antitumor potential of gemcitabine in an orthotopic mouse model through suppression of the inflammatory microenvironment

PubMed Central

Prasad, Sahdeo; Yadav, Vivek R.; Sung, Bokyung; Gupta, Subash C.; Tyagi, Amit K.; Aggarwal, Bharat B.

2016-01-01

The development of chemoresistance in human pancreatic cancer is one reason for the poor survival rate for patients with this cancer. Because multiple gene products are linked with chemoresistance, we investigated the ability of ursolic acid (UA) to sensitize pancreatic cancer cells to gemcitabine, a standard drug used for the treatment of pancreatic cancer. These investigations were done in AsPC-1, MIA PaCa-2, and Panc-28 cells and in nude mice orthotopically implanted with Panc-28 cells. In vitro, UA inhibited proliferation, induced apoptosis, suppressed NF-κB activation and its regulated proliferative, metastatic, and angiogenic proteins. UA (20 μM) also enhanced gemcitabine (200 nM)-induced apoptosis and suppressed the expression of NF-κB-regulated proteins. In the nude mouse model, oral administration of UA (250 mg/kg) suppressed tumor growth and enhanced the effect of gemcitabine (25 mg/kg). Furthermore, the combination of UA and gemcitabine suppressed the metastasis of cancer cells to distant organs such as liver and spleen. Immunohistochemical analysis showed that biomarkers of proliferation (Ki-67) and microvessel density (CD31) were suppressed by the combination of UA and gemcitabine. UA inhibited the activation of NF-κB and STAT3 and the expression of tumorigenic proteins regulated by these inflammatory transcription factors in tumor tissue. Furthermore, the combination of two agents decreased the expression of miR-29a, closely linked with tumorigenesis, in the tumor tissue. UA was found to be bioavailable in animal serum and tumor tissue. These results suggest that UA can inhibit the growth of human pancreatic tumors and sensitize them to gemcitabine by suppressing inflammatory biomarkers linked to proliferation, invasion, angiogenesis, and metastasis. PMID:26909608

Randomized phase II study comparing gemcitabine plus dacarbazine versus dacarbazine alone in patients with previously treated soft tissue sarcoma: a Spanish Group for Research on Sarcomas study.

PubMed

García-Del-Muro, Xavier; López-Pousa, Antonio; Maurel, Joan; Martín, Javier; Martínez-Trufero, Javier; Casado, Antonio; Gómez-España, Auxiliadora; Fra, Joaquín; Cruz, Josefina; Poveda, Andrés; Meana, Andrés; Pericay, Carlos; Cubedo, Ricardo; Rubió, Jordi; De Juan, Ana; Laínez, Nuria; Carrasco, Juan Antonio; de Andrés, Raquel; Buesa, José M

2011-06-20

To assess the activity and toxicity of the combination of gemcitabine plus dacarbazine (DTIC) in patients with advanced soft tissue sarcoma (STS) in a randomized, multicenter, phase II study using DTIC alone as a control arm. Patients with previously treated advanced STS were randomly assigned to receive either fixed-dose rate gemcitabine (10 mg/m2/min) at 1800 mg/m2 followed by DTIC at 500 mg/m2 every 2 weeks, or DTIC alone at 1200 mg/m2 every 3 weeks. The primary end point of the study was progression-free rate (PFR) at 3 months. From November 2005 to September 2008, 113 patients were included. PFR at 3 months was 56% for gemcitabine plus DTIC versus 37% for DTIC alone (P = .001). Median progression-free survival was 4.2 months versus 2 months (hazard ratio [HR], 0.58; 95% CI, 0.39 to 0.86; P = .005), and median overall survival was 16.8 months versus 8.2 months (HR, 0.56; 95% CI, 0.36 to 0.90; P = .014); both favored the arm of gemcitabine plus DTIC. Gemcitabine plus DTIC was also associated with a higher objective response or higher stable disease rate than was DTIC alone (49% v 25%; P = .009). Severe toxicities were uncommon, and treatment discontinuation for toxicity was rare. Granulocytopenia was the more common serious adverse event, but febrile neutropenia was uncommon. Asthenia, emesis, and stomatitis were the most frequent nonhematologic effects. The combination of gemcitabine and DTIC is active and well tolerated in patients with STS, providing in this phase II randomized trial superior progression-free survival and overall survival than DTIC alone. This regimen constitutes a valuable therapeutic alternative for these patients.

Carbon Ion Radiation Therapy With Concurrent Gemcitabine for Patients With Locally Advanced Pancreatic Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shinoto, Makoto, E-mail: shinoto@saga-himat.jp; Ion Beam Therapy Center, SAGA HIMAT Foundation, Tosu; Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka

Purpose: To determine, in the setting of locally advanced pancreatic cancer, the maximum tolerated dose of carbon ion radiation therapy (C-ion RT) and gemcitabine dose delivered concurrently and to estimate local effect and survival. Methods and Materials: Eligibility included pathologic confirmation of pancreatic invasive ductal carcinomas and radiographically unresectable disease without metastasis. Concurrent gemcitabine was administered on days 1, 8, and 15, and the dose levels were escalated from 400 to 1000 mg/m{sup 2} under the starting dose level (43.2 GyE) of C-ion RT. The dose levels of C-ion RT were escalated from 43.2 to 55.2 GyE at 12 fractions undermore » the fixed recommended gemcitabine dose determined. Results: Seventy-six patients were enrolled. Among the 72 treated patients, dose-limiting toxicity was observed in 3 patients: grade 3 infection in 1 patient and grade 4 neutropenia in 2 patients. Only 1 patient experienced a late grade 3 gastric ulcer and bleeding 10 months after C-ion RT. The recommended dose of gemcitabine with C-ion RT was found to be 1000 mg/m{sup 2}. The dose of C-ion RT with the full dose of gemcitabine (1000 mg/m{sup 2}) was safely increased to 55.2 GyE. The freedom from local progression rate was 83% at 2 years using the Response Evaluation Criteria in Solid Tumors. The 2-year overall survival rates in all patients and in the high-dose group with stage III (≥45.6 GyE) were 35% and 48%, respectively. Conclusions: Carbon ion RT with concurrent full-dose gemcitabine was well tolerated and effective in patients with unresectable locally advanced pancreatic cancer.« less

Intra-tumoral heterogeneity of gemcitabine delivery and mass transport in human pancreatic cancer

NASA Astrophysics Data System (ADS)

Koay, Eugene J.; Baio, Flavio E.; Ondari, Alexander; Truty, Mark J.; Cristini, Vittorio; Thomas, Ryan M.; Chen, Rong; Chatterjee, Deyali; Kang, Ya'an; Zhang, Joy; Court, Laurence; Bhosale, Priya R.; Tamm, Eric P.; Qayyum, Aliya; Crane, Christopher H.; Javle, Milind; Katz, Matthew H.; Gottumukkala, Vijaya N.; Rozner, Marc A.; Shen, Haifa; Lee, Jeffrey E.; Wang, Huamin; Chen, Yuling; Plunkett, William; Abbruzzese, James L.; Wolff, Robert A.; Maitra, Anirban; Ferrari, Mauro; Varadhachary, Gauri R.; Fleming, Jason B.

2014-12-01

There is substantial heterogeneity in the clinical behavior of pancreatic cancer and in its response to therapy. Some of this variation may be due to differences in delivery of cytotoxic therapies between patients and within individual tumors. Indeed, in 12 patients with resectable pancreatic cancer, we previously demonstrated wide inter-patient variability in the delivery of gemcitabine as well as in the mass transport properties of tumors as measured by computed tomography (CT) scans. However, the variability of drug delivery and transport properties within pancreatic tumors is currently unknown. Here, we analyzed regional measurements of gemcitabine DNA incorporation in the tumors of the same 12 patients to understand the degree of intra-tumoral heterogeneity of drug delivery. We also developed a volumetric segmentation approach to measure mass transport properties from the CT scans of these patients and tested inter-observer agreement with this new methodology. Our results demonstrate significant heterogeneity of gemcitabine delivery within individual pancreatic tumors and across the patient cohort, with gemcitabine DNA incorporation in the inner portion of the tumors ranging from 38 to 74% of the total. Similarly, the CT-derived mass transport properties of the tumors had a high degree of heterogeneity, ranging from minimal difference to almost 200% difference between inner and outer portions of the tumor. Our quantitative method to derive transport properties from CT scans demonstrated less than 5% difference in gemcitabine prediction at the average CT-derived transport value across observers. These data illustrate significant inter-patient and intra-tumoral heterogeneity in the delivery of gemcitabine, and highlight how this variability can be reproducibly accounted for using principles of mass transport. With further validation as a biophysical marker, transport properties of tumors may be useful in patient selection for therapy and prediction of therapeutic outcome.

Safety and effectiveness of gemcitabine in 260 patients with biliary tract cancer in a Japanese clinical practice based on post-marketing surveillance in Japan.

PubMed

Okubo, Sumiko; Nishiuma, Shinichi; Kobayashi, Noriko; Taketsuna, Masanori; Taniai, Hisashi

2012-11-01

Gemcitabine was approved for the treatment of biliary tract cancer in 2006 in Japan. While biliary tract cancer is usually associated with patients 70 years of age or older and/or those who tend to have underlying liver dysfunction, data on this population were limited in the Japanese Phase II study of gemcitabine. Thus, further evaluation of safety and effectiveness in this population was planned. This special post-marketing surveillance was conducted as an observational study on the use of gemcitabine in a clinical practice setting. Gemcitabine-naïve patients with biliary tract cancer were enrolled from 2006 to 2008 and observed over 12 months; one or more doses of gemcitabine were administered during the period. Data such as patient background, treatment details, adverse events occurring during the observational period, laboratory values of liver enzyme and survival status were collected 3 and 12 months after the start of therapy. Of the 285 patients registered for the study, 260 were included in the analysis. The mean age was 66.9 years. There were 120 patients (46.2%) classified as elderly (70 years or older). Haematotoxicities were the most common adverse drug reactions. In the elderly and the non-elderly, adverse drug reactions (serious) occurred in 48.3% (20.8%) and 50.7% (12.9%), respectively. The overall estimated 1-year survival rate was 52.5% (95% confidence interval, 45.9-58.7%). In line with previous clinical and post-marketing studies conducted in Japan, the results of this study suggest that gemcitabine could be used safely and effectively for biliary tract cancer patients including the elderly.

Pancreatic cancer cells resistance to gemcitabine: the role of MUC4 mucin.

PubMed

Bafna, S; Kaur, S; Momi, N; Batra, S K

2009-10-06

A major obstacle to the successful management of pancreatic cancer is to acquire resistance to the existing chemotherapeutic agents. Resistance to gemcitabine, the standard first-line chemotherapeutic agent for advanced and metastatic pancreatic cancer, is mainly attributed to an altered apoptotic threshold in the pancreatic cancer. The MUC4 transmembrane glycoprotein is aberrantly overexpressed in the pancreatic cancer and recently, has been shown to increase pancreatic tumour cell growth by the inhibition of apoptosis. Effect of MUC4 on pancreatic cancer cells resistance to gemcitabine was studied in MUC4-expressing and MUC4-knocked down pancreatic cancer cell lines after treatment with gemcitabine by Annexin-V staining, DNA fragmentation assay, assessment of mitochondrial cytochrome c release, immunoblotting and co-immunoprecipitation techniques. Annexin-V staining and DNA fragmentation experiment demonstrated that MUC4 protects CD18/HPAF pancreatic cancer cells from gemcitabine-induced apoptosis. In concert with these results, MUC4 also attenuated mitochondrial cytochrome c release and the activation of caspase-9. Further, our results showed that MUC4 exerts anti-apoptotic function through HER2/extracellular signal-regulated kinase-dependent phosphorylation and inactivation of the pro-apoptotic protein Bad. Our results elucidate the function of MUC4 in imparting resistance to pancreatic cancer cells against gemcitabine through the activation of anti-apoptotic pathways and, thereby, promoting cell survival.

Network modeling of kinase inhibitor polypharmacology reveals pathways targeted in chemical screens

PubMed Central

Ursu, Oana; Gosline, Sara J. C.; Beeharry, Neil; Fink, Lauren; Bhattacharjee, Vikram; Huang, Shao-shan Carol; Zhou, Yan; Yen, Tim; Fraenkel, Ernest

2017-01-01

Small molecule screens are widely used to prioritize pharmaceutical development. However, determining the pathways targeted by these molecules is challenging, since the compounds are often promiscuous. We present a network strategy that takes into account the polypharmacology of small molecules in order to generate hypotheses for their broader mode of action. We report a screen for kinase inhibitors that increase the efficacy of gemcitabine, the first-line chemotherapy for pancreatic cancer. Eight kinase inhibitors emerge that are known to affect 201 kinases, of which only three kinases have been previously identified as modifiers of gemcitabine toxicity. In this work, we use the SAMNet algorithm to identify pathways linking these kinases and genetic modifiers of gemcitabine toxicity with transcriptional and epigenetic changes induced by gemcitabine that we measure using DNaseI-seq and RNA-seq. SAMNet uses a constrained optimization algorithm to connect genes from these complementary datasets through a small set of protein-protein and protein-DNA interactions. The resulting network recapitulates known pathways including DNA repair, cell proliferation and the epithelial-to-mesenchymal transition. We use the network to predict genes with important roles in the gemcitabine response, including six that have already been shown to modify gemcitabine efficacy in pancreatic cancer and ten novel candidates. Our work reveals the important role of polypharmacology in the activity of these chemosensitizing agents. PMID:29023490

miR-34 increases in vitro PANC-1 cell sensitivity to gemcitabine via targeting Slug/PUMA.

PubMed

Zhang, Qing-An; Yang, Xu-Hai; Chen, Dong; Yan, Xiang; Jing, Fu-Chun; Liu, Hong-Qian; Zhang, Ronghua

2018-01-01

miR-34 was deregulated in tumor tissues compared with corresponding noncancerous tissue samples. Furthermore, miR-34 may contribute to cancer-stromal interaction associated with cancer progression. However, whether miR-34 could decrease chemoresistance of cancer cells to chemotherapeutic agent remains unclear. In our study, we examined whether overexpression of miR-34 could sensitize gemcitabine -mediated apoptosis in human pancreatic cancer PANC-1 cells. We found that miR-34 markedly induced gemcitabine -mediated apoptosis in PANC-1 cells. miR-34 induced down-regulation of Slug expression and upregulation of p53 up-regulated modulator of apoptosis (PUMA) expression. The over-expression of Slug or downregulation of PUMA by Slug cDNA or PUMA siRNA transfection markedly blocked miR-34-induced gemcitabine sensitization. Furthermore, miR-34 induced PUMA expression by downregulation of Slug. Taken together, our study demonstrates that miR-34 enhances sensitization against gemcitabine-mediated apoptosis through the down-regulation of Slug expression, and up-regulation of Slug-dependent PUMA expression.

Gemcitabine and capecitabine as third- or later-line therapy for refractory advanced colorectal cancer: a retrospective study.

PubMed

Salgado, Mercedes; Reboredo, Margarita; Mendez, Juan Carlos; Quintero, Guillermo; Pellón, María Luz; Romero, Carlos; Jorge, Mónica; Montes, Ana Fernández; Valladares-Ayerbes, Manuel; Ramos, Manuel; Varela, Silvia; Alonso, Miguel Ángel

2013-09-01

To evaluate gemcitabine plus capecitabine as third-line or later-line therapy in patients with refractory advanced colorectal cancer (CRC) who maintain a good performance status (PS). We retrospectively evaluated patients who had failed at least two lines of therapy or had contraindication to standard therapy and received gemcitabine (1,000 mg/m(2), d1 biweekly) plus capecitabine (1,700 mg/m(2)/day, d1-7 every two weeks) in a compassionate use program. Thirty-nine patients were enrolled. The majority (85%) had ECOG PS 1. Gemcitabine plus capecitabine was administered as third- and fourth-line in 49% and 23% of patients, respectively; and as fifth-line or later-line in 28%. A clinical benefit of 21% was found. The median progression-free survival and overall survival were 3.0 and 7.3 months, respectively. Toxicity was mild to moderate, with no reported grade 4 toxicities. Gemcitabine plus capecitabine was safe and well-tolerated. While the efficacy of this regimen was modest in terms of response, the survival data were acceptable and consistent with previous publications on this setting.

Gemcitabine plus sorafenib in patients with advanced pancreatic cancer: a phase II trial of the University of Chicago Phase II Consortium

PubMed Central

Wroblewski, Kristen; Wallace, James A.; Hall, Michael J.; Locker, Gershon; Nattam, Sreenivasa; Agamah, Edem; Stadler, Walter M.; Vokes, Everett E.

2015-01-01

Summary Background Sorafenib, an inhibitor of B-raf, VEGFR2, and PDGFR-β, has activity against pancreatic cancer in preclinical models. In a phase I trial of gemcitabine plus sorafenib, 57% of pancreatic cancer patients achieved stable disease. Patients and methods We conducted a multi-center phase II trial of sorafenib plus gemcitabine in chemo-naïve patients with histologicallyconfirmed, advanced pancreatic cancer. Patients received sorafenib 400 mg twice daily and gemcitabine 1,000 mg/m2 on days 1, 8 and 15 of a 28 day cycle. Results Seventeen patients enrolled at 4 centers; 13 were evaluable for response. There were no objective responses; 18% had stable disease. Median overall survival was 4.0 months (95% CI: 3.4, 5.9); median progression-free survival was 3.2 months (95% CI: 1.6, 3.6). Grade 3/4 toxicities included thrombosis in 18% of patients, dehydration or hand-foot syndrome in 12%, and hypertension or gastrointestinal bleeding in 6%. Conclusion Gemcitabine plus sorafenib is inactive in advanced pancreatic cancer. PMID:20803052

The novel sigma-2 receptor ligand SW43 stabilizes pancreas cancer progression in combination with gemcitabine

PubMed Central

2010-01-01

Background Sigma-2 receptors are over-expressed in proliferating cancer cells, making an attractive target for the targeted treatment of pancreatic cancer. In this study, we investigated the role of the novel sigma-2 receptor ligand SW43 to induce apoptosis and augment standard chemotherapy. Results The binding affinity for sigma-2 ligands is high in pancreas cancer, and they induce apoptosis with a rank order of SV119 < SW43 < SRM in vitro. Combining these compounds with gemcitabine further increased apoptosis and decreased viability. Our in vivo model showed that sigma-2 ligand treatment decreased tumor volume to the same extent as gemcitabine. However, SW43 combination treatment with gemcitabine was superior to the other compounds and resulted in stabilization of tumor volume during treatment, with minimal toxicities. Conclusions This study shows that the sigma-2 ligand SW43 has the greatest capacity to augment gemcitabine in a pre-clinical model of pancreas cancer and has provided us with the rationale to move this compound forward with clinical investigations for patients with pancreatic cancer. PMID:21092190

Apicidin sensitizes pancreatic cancer cells to gemcitabine by epigenetically regulating MUC4 expression.

PubMed

Ansari, Daniel; Urey, Carlos; Hilmersson, Katarzyna Said; Bauden, Monika P; Ek, Fredrik; Olsson, Roger; Andersson, Roland

2014-10-01

Mucin 4 (MUC4) has been linked to resistance to gemcitabine in pancreatic cancer cells. The aim of the present study was to assess whether epigenetic control of MUC4 expression can sensitize pancreatic cancer cells to gemcitabine treatment. A 76-member combined epigenetics and phosphatase small-molecule inhibitor library was screened for anti-proliferative activity against the MUC4(+) gemcitabine-resistant pancreatic cancer cell line Capan-1, followed by high-content screening of protein expression. Apicidin, a histone deacetylase inhibitor, showed the greatest anti-proliferative activity with a lethal dose 50 (LD50) value of 5.17 μM. Apicidin significantly reduced the expression of MUC4 and its transcription factor hepatocyte nuclear factor 4α. Combined treatment with a sub-therapeutic concentration of apicidin and gemcitabine synergistically inhibited growth of Capan-1 cells. Apicidin appears to be a novel anti-proliferative agent against pancreatic cancer cells that may reverse chemoresistance by epigenetically regulating MUC4 expression. Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

A method to assess the migration properties of cell-derived microparticles within a living tissue.

PubMed

Hoang, Thang Q; Rampon, Christine; Freyssinet, Jean-Marie; Vriz, Sophie; Kerbiriou-Nabias, Danièle

2011-09-01

Cells undergoing activation or apoptosis exhibit plasma membrane changes, leading to the formation of shed vesicles (microparticles, MP). Although their effects on recipient cells in vitro, and their ability to support inflammatory or thrombotic events in the circulation have been studied, the spreading of such vesicles in tissues is still elusive. Our aim was to set up a method to examine the behavior of these vesicles in vivo. We examined the persistence of green-fluorescent microparticles (fMP), prepared after Ca2+ ionophore activation (iono-fMP) or apoptogenic treatment (eto-fMP) of human Jurkat T lymphoblastic or non-hematopoietic embryonic kidney (HEK) cell lines, following injection in zebrafish embryos 2h after egg fertilization. One hour post-injection, iono-fMP issued from both cell types formed a fluorescent dispersal in the intercellular space of embryos. In contrast, eto-fMP or MP deprived of sialic acid at their membrane, gathered together at the site of injection. We propose a method characterizing the abilities of MP to spread in the intercellular space. We showed that MP produced by apoptosis of T cells and those deprived of sialic acid at their membrane do not diffuse within the living cells. On the contrary, MP shed upon calcium induced activation of T and HEK cells, diffuse at a distance and spread in the intercellular space. The fate of injected MP relies on the type of induction rather than the cell species and results provide a model to test the ability of vesicles to interact locally or to spread outside of the site of production. Copyright © 2011 Elsevier B.V. All rights reserved.

Anti-Neoplastic Cytotoxicity of Gemcitabine-(C4-amide)-[anti-EGFR] in Dual-combination with Epirubicin-(C3-amide)-[anti-HER2/neu] against Chemotherapeutic-Resistant Mammary Adenocarcinoma (SKBr-3) and the Complementary Effect of Mebendazole

PubMed Central

Coyne, CP; Jones, Toni; Bear, Ryan

2015-01-01

Aims Delineate the feasibility of simultaneous, dual selective “targeted” chemotherapeutic delivery and determine if this molecular strategy can promote higher levels anti-neoplastic cytotoxicity than if only one covalent immunochemotherapeutic is selectively “targeted” for delivery at a single membrane associated receptor over-expressed by chemotherapeutic-resistant mammary adenocarcinoma. Methodology Gemcitabine and epirubicin were covalently bond to anti-EGFR and anti-HER2/neu utilizing a rapid multi-phase synthetic organic chemistry reaction scheme. Determination that 96% or greater gemcitabine or epirubicin content was covalently bond to immunoglobulin fractions following size separation by micro-scale column chromatography was established by methanol precipitation analysis. Residual binding-avidity of gemcitabine-(C4-amide)-[anti-EG-FR] applied in dual-combination with epirubicin-(C3-amide)-[anti-HER2/neu] was determined by cell-ELIZA utilizing chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) populations. Lack of fragmentation or polymerization was validated by SDS-PAGE/immunodetection/chemiluminescent autoradiography. Anti-neoplastic cytotoxic potency was determined by vitality stain analysis of chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) monolayers known to uniquely over-express EGFR (2 × 105/cell) and HER2/neu (1 × 106/cell) receptor complexes. The covalent immunochemotherapeutics gemcitabine-(C4-amide)-[anti-EGFR] and epirubicin-(C3-amide)-[anti-HER2/neu] were applied simultaneously in dual-combination to determine their capacity to collectively evoke elevated levels of anti-neoplastic cytotoxicity. Lastly, the tubulin/microtubule inhibitor mebendazole evaluated to determine if it’s potential to complemented the anti-neoplastic cytotoxic properties of gemcitabine-(C4-amide)-[anti-EGFR] in dual-combination with epirubicin-(C3-amide)-[anti-HER2/neu]. Results Dual-combination of gemcitabine-(C4-amide)-[anti-EGFR] with epirubicin-(C3-amide)-[anti-HER2/neu] produced greater levels of anti-neoplastic cytotoxicity than either of the covalent immunochemotherapeutics alone. The benzimidazole microtubule/tubulin inhibitor, mebendazole complemented the anti-neoplastic cytotoxicity of gemcitabine-(C4-amide)-[anti-EGFR] in dual-combination with epirubicin-(C3-amide)-[anti-HER2/neu]. Conclusions The dual-combination of gemcitabine-(C4-amide)-[anti-EGFR] with epirubicin-(C3-amide)-[anti-HER2/neu] produced higher levels of selectively “targeted” anti-neoplastic cytotoxicity against chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) than either covalent immunochemotherapeutic alone. The benzimidazole tubulin/microtubule inhibitor, mebendazole also possessed anti-neoplastic cytotoxicity against chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) and complemented the potency and efficacy of gemcitabine-(C4-amide)-[anti-EGFR] in dual-combination with epirubicin-(C3-amide)-[anti-HER2/neu]. PMID:25844392

The MUC4 mucin mediates gemcitabine resistance of human pancreatic cancer cells via the Concentrative Nucleoside Transporter family.

PubMed

Skrypek, N; Duchêne, B; Hebbar, M; Leteurtre, E; van Seuningen, I; Jonckheere, N

2013-03-28

The fluorinated analog of deoxycytidine, Gemcitabine (Gemzar), is the main chemotherapeutic drug in pancreatic cancer, but survival remains weak mainly because of the high resistance of tumors to the drug. Recent works have shown that the mucin MUC4 may confer an advantage to pancreatic tumor cells by modifying their susceptibility to drugs. However, the cellular mechanism(s) responsible for this MUC4-mediated resistance is unknown. The aim of this work was to identify the cellular mechanisms responsible for gemcitabine resistance linked to MUC4 expression. CAPAN-2 and CAPAN-1 adenocarcinomatous pancreatic cancer (PC) cell lines were used to establish stable MUC4-deficient clones (MUC4-KD) by shRNA interference. Measurement of the IC50 index using tetrazolium salt test indicated that MUC4-deficient cells were more sensitive to gemcitabine. This was correlated with increased Bax/BclXL ratio and apoptotic cell number. Expression of Equilibrative/Concentrative Nucleoside Transporter (hENT1, hCNT1/3), deoxycytidine kinase (dCK), ribonucleotide reductase (RRM1/2) and Multidrug-Resistance Protein (MRP3/4/5) was evaluated by quantitative RT-PCR (qRT-PCR) and western blotting. Alteration of MRP3, MRP4, hCNT1 and hCNT3 expression was observed in MUC4-KD cells, but only hCNT1 alteration was correlated to MUC4 expression and sensitivity to gemcitabine. Decreased activation of MAPK, JNK and NF-κB pathways was observed in MUC4-deficient cells, in which the NF-κB pathway was found to have an important role in both sensitivity to gemcitabine and hCNT1 regulation. Finally, and in accordance with our in vitro data, we found that MUC4 expression was conversely correlated to that of hCNT1 in tissues from patients with pancreatic adenocarcinoma. This work describes a new mechanism of PC cell resistance to gemcitabine, in which the MUC4 mucin negatively regulates the hCNT1 transporter expression via the NF-κB pathway. Altogether, these data point out to MUC4 and hCNT1 as potential targets to ameliorate the response of pancreatic tumors to gemcitabine treatment.

The MUC4 mucin mediates gemcitabine resistance of human pancreatic cancer cells via the Concentrative Nucleoside Transporter family

PubMed Central

Skrypek, Nicolas; Duchêne, Bélinda; Hebbar, Mohamed; Leteurtre, Emmanuelle; Van Seuningen, Isabelle; Jonckheere, Nicolas

2013-01-01

The fluorinated analog of deoxycytidine, Gemcitabine (Gemzar®), is the main chemotherapy in pancreatic cancer, but survival remains weak mainly because of the high resistance of tumors to the drug. Recent works have shown that the mucin MUC4 may confer an advantage to pancreatic tumor cells by modifying their susceptibility to drugs. However, the cellular mechanism(s) responsible for this MUC4-mediated resistance is unknown. The aim of this work was to identify the cellular mechanisms responsible for gemcitabine resistance linked to MUC4 expression. CAPAN-2 and CAPAN-1 adenocarcinomatous pancreatic cancer cell lines were used to establish stable MUC4-deficient clones (MUC4-KD) by shRNA interference. Measurement of the IC50 index using tetrazolium salt test indicated that MUC4-deficient cells were more sensitive to gemcitabine. This was correlated with increased Bax/BclXL ratio and apoptotic cell number. Expression of Equilibrative/Concentrative Nucleoside Transporter (hENT1, hCNT1/3), deoxycytidine kinase (dCK), ribonucleotide reductase (RRM1/2) and Multidrug-resistance Protein (MRP3/4/5) was evaluated by quantitative RT-PCR (qRT-PCR) and Western-blotting. Alteration of MRP3, MRP4, hCNT1 and hCNT3 expression was observed in MUC4-KD cells but only hCNT1 alteration was correlated to MUC4 expression and sensitivity to gemcitabine. Decreased activation of MAPK, JNK and NF-κB pathways was observed in MUC4-deficient cells in which NF-κB pathway was found to play an important role both in sensitivity to gemcitabine and in hCNT1 regulation. Finally and accordingly to our in vitro data, we found that MUC4 expression was conversely correlated to that of hCNT1 in tissues from patients with pancreatic adenocarcinoma. This work describes a new mechanism of pancreatic cancer cell resistance to gemcitabine in which the MUC4 mucin negatively regulates the hCNT1 transporter expression via the NF-κB pathway. Altogether, these data point out to MUC4 and hCNT1 as potential targets to ameliorate the response of pancreatic tumors to gemcitabine treatment. PMID:22580602

A Phase Ib study of ruxolitinib + gemcitabine ± nab-paclitaxel in patients with advanced solid tumors.

PubMed

Bauer, Todd M; Patel, Manish R; Forero-Torres, Andres; George, Thomas J; Assad, Albert; Du, Yining; Hurwitz, Herbert

2018-01-01

Aberrant activation of the Janus-associated kinase (JAK)/signal transducer and activator of transcription (STAT) pathway is associated with increased malignant cell proliferation and survival. This Phase Ib study evaluated ruxolitinib, a potent JAK1/2 inhibitor, in combination with gemcitabine with or without nab-paclitaxel in patients with advanced solid tumors. Patients received ruxolitinib + gemcitabine (regimen A) or ruxolitinib + gemcitabine + nab-paclitaxel (regimen B). The objective of the dose-finding phase was to identify the maximum tolerated doses (MTDs) of ruxolitinib plus gemcitabine with or without nab-paclitaxel. Among 42 patients enrolled, the median age was 62.5 years, 81.0% had pancreatic cancer, and almost 62% had received prior systemic therapy. Regimen A was tolerated with standard doses of gemcitabine; regimen B was tolerated with reduced doses of gemcitabine/nab-paclitaxel or concomitant granulocyte colony-stimulating factor. The sponsor decided to terminate the study early due to the interim analysis results of the Phase III JANUS 1 study. Discontinuations were mainly due to radiologic or clinical disease progression (81.0% of patients). Median treatment durations were 55.5 days (cohort A0) and 150.5 days (pooled B cohorts). Four patients (pooled B cohorts) had dose-limiting toxicities: grade 3 pneumonia (n=1), grade 4 neutropenia (n=1), and grade 4 thrombocytopenia (n=2). The most common grade 3/4 hematologic adverse events (AEs) were anemia, thrombocytopenia, and neutropenia. Serious AEs occurring in ≥2 patients in cohort A0 or pooled B cohorts were abdominal pain, sepsis (cohort A0), dehydration, anemia, and asthenia (pooled B cohorts). Overall response rates (ORRs) were 12.5% in cohort A0 and 38.5% in pooled B cohorts. Among patients with pancreatic cancer, ORR was 23.5% (14.0% cohort A0 30.0% pooled B cohorts). The study was terminated early prior to reaching MTDs per sponsor decision; although ruxolitinib plus gemcitabine with or without nab-paclitaxel was generally safe and well tolerated in patients with advanced solid tumors, this combination will not be pursued further.

Phase I dose-escalation study of copanlisib in combination with gemcitabine or cisplatin plus gemcitabine in patients with advanced cancer.

PubMed

Kim, R D; Alberts, S R; Peña, C; Genvresse, I; Ajavon-Hartmann, A; Xia, C; Kelly, A; Grilley-Olson, J E

2018-02-20

Copanlisib is a pan-class I phosphatidylinositol 3-kinase (PI3K) inhibitor with predominant PI3K-α/δ activity that has demonstrated clinical activity and manageable safety when administered as monotherapy in a phase II study. Combination therapy may overcome compensatory signalling that could occur with PI3K pathway inhibition, resulting in enhanced inhibitory activity, and preclinical studies of copanlisib with gemcitabine have demonstrated potent anti-tumour activity in vivo. A phase I, open-label, dose-escalation study to evaluate the safety, tolerability and recommended phase II dose (RP2D) of copanlisib with gemcitabine or with cisplatin plus gemcitabine (CisGem) in patients with advanced malignancies, including an expansion cohort in patients with biliary tract cancer (BTC) at the RP2D of copanlisib plus CisGem. Copanlisib and gemcitabine were administered on days 1, 8 and 15 of a 28-day cycle; maximum tolerated dose (MTD) and RP2D of copanlisib were determined. Copanlisib plus CisGem was administered on days 1 and 8 of a 21-day cycle; pharmacokinetics and biomarkers were assessed. Fifty patients received treatment as follows: dose-escalation cohorts, n=16; copanlisib plus CisGem cohort, n=14; and BTC expansion cohort, n=20. Copanlisib 0.8 mg kg -1 plus gemcitabine was the MTD and RP2D for both combinations. Common treatment-emergent adverse events included nausea (86%), hyperglycaemia (80%) and decreased platelet count (80%). Copanlisib exposure displayed a dose-proportional increase. No differences were observed upon co-administration of CisGem. Response rates were as follows: copanlisib plus gemcitabine, 6.3% (one partial response in a patient with peritoneal carcinoma); copanlisib plus CisGem, 12% (one complete response and three partial responses all in patients with BTC (response rate 17.4% in patients with BTC)). Mutations were detected in PIK3CA (1 out of 43), KRAS (10 out of 43) and BRAF (2 out of 22), with phosphate and tensin homologue protein loss in 41% (12 out of 29). Copanlisib plus CisGem demonstrated a manageable safety profile, favourable pharmacokinetics, and potentially promising clinical response.

Localization of (photo)respiration and CO2 re-assimilation in tomato leaves investigated with a reaction-diffusion model

PubMed Central

Berghuijs, Herman N. C.; Yin, Xinyou; Ho, Q. Tri; Verboven, Pieter; Nicolaï, Bart M.

2017-01-01

The rate of photosynthesis depends on the CO2 partial pressure near Rubisco, Cc, which is commonly calculated by models using the overall mesophyll resistance. Such models do not explain the difference between the CO2 level in the intercellular air space and Cc mechanistically. This problem can be overcome by reaction-diffusion models for CO2 transport, production and fixation in leaves. However, most reaction-diffusion models are complex and unattractive for procedures that require a large number of runs, like parameter optimisation. This study provides a simpler reaction-diffusion model. It is parameterized by both leaf physiological and leaf anatomical data. The anatomical data consisted of the thickness of the cell wall, cytosol and stroma, and the area ratios of mesophyll exposed to the intercellular air space to leaf surfaces and exposed chloroplast to exposed mesophyll surfaces. The model was used directly to estimate photosynthetic parameters from a subset of the measured light and CO2 response curves; the remaining data were used for validation. The model predicted light and CO2 response curves reasonably well for 15 days old tomato (cv. Admiro) leaves, if (photo)respiratory CO2 release was assumed to take place in the inner cytosol or in the gaps between the chloroplasts. The model was also used to calculate the fraction of CO2 produced by (photo)respiration that is re-assimilated in the stroma, and this fraction ranged from 56 to 76%. In future research, the model should be further validated to better understand how the re-assimilation of (photo)respired CO2 is affected by environmental conditions and physiological parameters. PMID:28880924

Localization of (photo)respiration and CO2 re-assimilation in tomato leaves investigated with a reaction-diffusion model.

PubMed

Berghuijs, Herman N C; Yin, Xinyou; Ho, Q Tri; Retta, Moges A; Verboven, Pieter; Nicolaï, Bart M; Struik, Paul C

2017-01-01

The rate of photosynthesis depends on the CO2 partial pressure near Rubisco, Cc, which is commonly calculated by models using the overall mesophyll resistance. Such models do not explain the difference between the CO2 level in the intercellular air space and Cc mechanistically. This problem can be overcome by reaction-diffusion models for CO2 transport, production and fixation in leaves. However, most reaction-diffusion models are complex and unattractive for procedures that require a large number of runs, like parameter optimisation. This study provides a simpler reaction-diffusion model. It is parameterized by both leaf physiological and leaf anatomical data. The anatomical data consisted of the thickness of the cell wall, cytosol and stroma, and the area ratios of mesophyll exposed to the intercellular air space to leaf surfaces and exposed chloroplast to exposed mesophyll surfaces. The model was used directly to estimate photosynthetic parameters from a subset of the measured light and CO2 response curves; the remaining data were used for validation. The model predicted light and CO2 response curves reasonably well for 15 days old tomato (cv. Admiro) leaves, if (photo)respiratory CO2 release was assumed to take place in the inner cytosol or in the gaps between the chloroplasts. The model was also used to calculate the fraction of CO2 produced by (photo)respiration that is re-assimilated in the stroma, and this fraction ranged from 56 to 76%. In future research, the model should be further validated to better understand how the re-assimilation of (photo)respired CO2 is affected by environmental conditions and physiological parameters.

Gemcitabine-Based Chemoradiation in the Treatment of Locally Advanced Head and Neck Cancer: Systematic Review of Literature and Meta-Analysis

PubMed Central

Szturz, Petr; Specenier, Pol; Merlano, Marco C.; Benasso, Marco; Van Gestel, Dirk; Wouters, Kristien; Van Laer, Carl; Van den Weyngaert, Danielle; Peeters, Marc; Vermorken, Jan

2016-01-01

Background. Platinum-based concurrent chemoradiation (CCRT) improves locoregional control and overall survival of locoregionally advanced (LA) squamous cell carcinoma of the head and neck (SCCHN) when compared to radiotherapy alone, but this approach is hampered by significant toxicity. Therefore, alternative ways to enhance the radiation effects are worth investigating. Gemcitabine (2′,2′-difluorodeoxycytidine), in addition to its activity against a variety of solid tumors, including SCCHN, is one of the most potent radiosensitizers, and it has an overall favorable safety profile. In this paper, the clinical experience with gemcitabine-based chemoradiation in the treatment of patients with LA-SCCHN is reviewed. Methods. We conducted a review of the literature on the clinical experience with radiotherapy combined with either single-agent gemcitabine or gemcitabine/cisplatin-based polychemotherapy for the treatment of patients with LA-SCCHN. We also searched abstracts in databases of major international oncology meetings from the last 20 years. A meta-analysis was performed to calculate pooled proportions with 95% confidence intervals (CIs) for complete response rate and grade 3–4 acute mucositis rate. Results. A total of 13 papers were eligible for the literature review. For schedules using a gemcitabine dose intensity (DI) below 50 mg/m2 per week, the complete response rate was 86% (95% CI, 74%–93%) with grade 3–4 acute mucositis rate of 38% (95% CI, 27%–50%) and acceptable late toxicity. In one of the studies employing such low DIs, survival data were provided showing a 3-year overall survival of 50%. Compared with DI ≥50 mg/m2 per week, there was no difference in the complete response rate (71%; 95% CI, 55%–83%; p = .087) but a significantly higher (p < .001) grade 3–4 acute mucositis rate of 74% (95% CI, 62%–83%), often leading to treatment interruptions (survival data provided in 8 studies; 3-year overall survival, 27%–63%). Late toxicity comprising mainly dysphagia was generally underreported, whereas information about xerostomia and skin fibrosis was scarce. Conclusion. This review highlights the radiosensitizing potential of gemcitabine and suggests that even very low dosages (less than 50 mg/m2 per week) provide a sufficient therapeutic ratio and therefore should be further investigated. Refinements in radiation schemes, including intensity-modulated radiation therapy, in combination with low-dose gemcitabine and targeted agents, such as cetuximab, are currently being investigated. Implications for Practice: Cisplatin-based concurrent chemoradiation (CCRT) has become the standard treatment of locally advanced head and neck cancer (LAHNC). This approach is hampered by significant toxicity. This paper reviews the studies using gemcitabine as an alternative radio-sensitizer for CCRT in patients with LAHNC. In this capacity, despite its mild intrinsic toxicity, gemcitabine comes with high rates of severe mucositis when used in dosages exceeding 50 mg/m2 per week. CCRT with low-dose gemcitabine provides a sufficient therapeutic ratio, combining clinical activity, similar to the higher-dose regimens, with lower toxicity. Further investigation is warranted. PMID:26712958

Sulforaphane counteracts aggressiveness of pancreatic cancer driven by dysregulated Cx43-mediated gap junctional intercellular communication

PubMed Central

Zhang, Yiyao; Isayev, Orkhan; Heilmann, Katharina; Schoensiegel, Frank; Liu, Li; Nessling, Michelle; Richter, Karsten; Labsch, Sabrina; Nwaeburu, Clifford C.; Mattern, Juergen; Gladkich, Jury; Giese, Nathalia; Werner, Jens; Schemmer, Peter; Gross, Wolfgang; Gebhard, Martha M.; Gerhauser, Clarissa; Schaefer, Michael; Herr, Ingrid

2014-01-01

The extreme aggressiveness of pancreatic ductal adenocarcinoma (PDA) has been associated with blocked gap junctional intercellular communication (GJIC) and the presence of cancer stem cells (CSCs). We examined whether disturbed GJIC is responsible for a CSC phenotype in established and primary cancer cells and patient tissue of PDA using interdisciplinary methods based in physiology, cell and molecular biology, histology and epigenetics. Flux of fluorescent dyes and gemcitabine through gap junctions (GJs) was intact in less aggressive cells but not in highly malignant cells with morphological dysfunctional GJs. Among several connexins, only Cx43 was expressed on the cell surface of less aggressive and GJIC-competent cells, whereas Cx43 surface expression was absent in highly malignant, E-cadherin-negative and GJIC-incompetent cells. The levels of total Cx43 protein and Cx43 phosphorylated at Ser368 and Ser279/282 were high in normal tissue but low to absent in malignant tissue. si-RNA-mediated inhibition of Cx43 expression in GJIC-competent cells prevented GJIC and induced colony formation and the expression of stem cell-related factors. The bioactive substance sulforaphane enhanced Cx43 and E-cadherin levels, inhibited the CSC markers c-Met and CD133, improved the functional morphology of GJs and enhanced GJIC. Sulforaphane altered the phosphorylation of several kinases and their substrates and inhibition of GSK3, JNK and PKC prevented sulforaphane-induced CX43 expression. The sulforaphane-mediated expression of Cx43 was not correlated with enhanced Cx43 RNA expression, acetylated histone binding and Cx43 promoter de-methylation, suggesting that posttranslational phosphorylation is the dominant regulatory mechanism. Together, the absence of Cx43 prevents GJIC and enhances aggressiveness, whereas sulforaphane counteracts this process, and our findings highlight dietary co-treatment as a viable treatment option for PDA. PMID:24742583

Sulforaphane counteracts aggressiveness of pancreatic cancer driven by dysregulated Cx43-mediated gap junctional intercellular communication.

PubMed

Forster, Tobias; Rausch, Vanessa; Zhang, Yiyao; Isayev, Orkhan; Heilmann, Katharina; Schoensiegel, Frank; Liu, Li; Nessling, Michelle; Richter, Karsten; Labsch, Sabrina; Nwaeburu, Clifford C; Mattern, Juergen; Gladkich, Jury; Giese, Nathalia; Werner, Jens; Schemmer, Peter; Gross, Wolfgang; Gebhard, Martha M; Gerhauser, Clarissa; Schaefer, Michael; Herr, Ingrid

2014-03-30

The extreme aggressiveness of pancreatic ductal adenocarcinoma (PDA) has been associated with blocked gap junctional intercellular communication (GJIC) and the presence of cancer stem cells (CSCs). We examined whether disturbed GJIC is responsible for a CSC phenotype in established and primary cancer cells and patient tissue of PDA using interdisciplinary methods based in physiology, cell and molecular biology, histology and epigenetics. Flux of fluorescent dyes and gemcitabine through gap junctions (GJs) was intact in less aggressive cells but not in highly malignant cells with morphological dysfunctional GJs. Among several connexins, only Cx43 was expressed on the cell surface of less aggressive and GJIC-competent cells, whereas Cx43 surface expression was absent in highly malignant, E-cadherin-negative and GJIC-incompetent cells. The levels of total Cx43 protein and Cx43 phosphorylated at Ser368 and Ser279/282 were high in normal tissue but low to absent in malignant tissue. si-RNA-mediated inhibition of Cx43 expression in GJIC-competent cells prevented GJIC and induced colony formation and the expression of stem cell-related factors. The bioactive substance sulforaphane enhanced Cx43 and E-cadherin levels, inhibited the CSC markers c-Met and CD133, improved the functional morphology of GJs and enhanced GJIC. Sulforaphane altered the phosphorylation of several kinases and their substrates and inhibition of GSK3, JNK and PKC prevented sulforaphane-induced CX43 expression. The sulforaphane-mediated expression of Cx43 was not correlated with enhanced Cx43 RNA expression, acetylated histone binding and Cx43 promoter de-methylation, suggesting that posttranslational phosphorylation is the dominant regulatory mechanism. Together, the absence of Cx43 prevents GJIC and enhances aggressiveness, whereas sulforaphane counteracts this process, and our findings highlight dietary co-treatment as a viable treatment option for PDA.

Gemcitabine treatment causes resistance and malignancy of pancreatic cancer stem-like cells via induction of lncRNA HOTAIR

PubMed Central

Wang, Li; Dong, Ping; Wang, Weiguo; Huang, Mingquan; Tian, Bole

2017-01-01

Gemcitabine is the first-line chemotherapeutic agent for advanced adenocarcinoma of the pancreas, despite the high risk of chemoresistance as a major disadvantage. In the past few years, significant advances have been made in the field of pancreatic cancer stem-like cells (CSCs) and their critical roles in drug resistance, invasion and metastasis, which are tightly regulated by long non-coding RNAs (lncRNAs). The present study demonstrated that HOX antisense intergenic RNA (HOTAIR) is not different between the pancreatic cancer cell line PANC-1 and its enriched CSC sub-population. However, after gemcitabine treatment, the expression levels of HOTAIR in CSCs were induced, but not in PANC-1 cells. HOTAIR induced by gemcitabine failed to cause chemoresistance, but promoted the clonogenicity, proliferation and migration of the cells. By introducing HOTAIR using lentivirus, chemoresistance was induced and the self-renewal capacity, proliferation and migration were significantly promoted. By contrast, HOTAIR knockdown in PANC-1 CSCs treated with or without gemcitabine decreased the cell proliferation, altered the cell cycle progression and induced apoptosis, demonstrating its critical roles in regulating the malignant character of PANC-1 CSCs. In conclusion, the present study demonstrated that HOTAIR may be induced by gemcitabine and acts as a tumor promoter by inhibiting the chemosensitivity, and promoting the self-renewal capacity, proliferation and migration of PANC-1 CSCs, which supports its potential application as a novel therapeutic approach for pancreatic cancer. PMID:29201179

Gemcitabine and vinorelbine (GV) versus cisplatin, gemcitabine and vinorelbine (CGV) as first-line treatment in advanced non small cell lung cancer: results of a prospective randomized phase II study.

PubMed

Esteban, Emilio; Fra, Joaquin; Fernández, Yolanda; Corral, Norberto; Vieitez, José M; Palacio, Isabel; de Sande, José L; Fernández, José L; Muñiz, Isabel; Villanueva, Noemi; Estrada, Enrique; Mareque, Beatriz; Uña, Esther; Buesa, José M; Lacave, Angel J

2006-05-01

The objective of this study was to assess whether adding cisplatin to gemcitabine/vinorelbine combination improves the clinical outcome in patients with non-small-cell lung cancer (NSCLC). Chemotherapy-naïve patients with advanced NSCLC; age < or = 75 years: Karnofsky performance status > or = 60%, and with adequate hematological, renal and hepatic function, were randomized into 2 treatment groups to receive Gemcitabine 1250 mg/m2 + vinorelbine 30 mg/m2 (GV group), or cisplatin 50 mg/m2 + gemcitabine 1000 mg/m2 + vinorelbine 25 mg/m2 (CGV group). All drugs were administered on days 1 and 8 every three weeks: From September 1999 to March 2003, 114 patients were enrolled. No statistically significant difference was observed in GV vs CGV group in objective response (37 versus 47%, respectively; P = 0.5), median time to progression (5 versus 5.8 months; P = 0.6), overall survival (9 versus 10 months; P = 0.9) and 1-year survival (26 versus 28%; P = 0.9). Conversely, toxicities were significantly higher for CGV, including grade 3-4 neutropenia (24 versus 45%); neutropenic fever (4 versus 14%, including one toxic death); grade 3-4 thrombocytopenia (2 versus 14%); and grade 3-4 emesis (2 versus 14%). Our results suggest that the combination of gemcitabine and vinorelbine is less toxic than three-drug combination with cisplatin while showing similar efficacy.

Human equilibrative nucleoside transporter 1 (hENT1) levels predict response to gemcitabine in patients with biliary tract cancer (BTC).

PubMed

Santini, Daniele; Schiavon, Gaia; Vincenzi, Bruno; Cass, Carol E; Vasile, Enrico; Manazza, Andrea D; Catalano, Vincenzo; Baldi, Giacomo Giulio; Lai, Raymond; Rizzo, Sergio; Giacobino, Alice; Chiusa, Luigi; Caraglia, Michele; Russo, Antonio; Mackey, John; Falcone, Alfredo; Tonini, Giuseppe

2011-01-01

Translational data suggest that nucleoside transporters, in particular human equilibrative nucleoside transporter 1 (hENT1), play an important role in predicting clinical outcome after gemcitabine chemotherapy for several types of cancer. The aim of this study was to retrospectively determine patients' outcome according to the expression of hENT1 in tumoral cells of patients receiving gemcitabine-based therapy. The immunohistochemistry analysis was performed on samples from thirty-one patients with unresectable biliary tract cancer (BTC) consecutively treated with first line gemcitabine-based regimens. Positive hENT1 staining patients were 21 (67.7%); negative hENT1 staining patients were 10 (32.3%). Statistical analysis revealed no association between baseline characteristics, toxicities and tumor response to gemcitabine and hENT1 levels. In the univariate analysis, HENT1 expression was significantly correlated with time to progression (TTP) (p=0.0394; HR 2.902, 95%CI 1.053-7.996). The median TTP was 6.33 versus 2.83 months, respectively in patients with positive versus negative hENT1 staining. Moreover, patients with positive hENT1 expression showed a longer median overall survival when compared with patients with low hENT1 expression (14 versus 7 months, respectively), but this difference did not reach the statistical significance (p=0.128). Therefore, hENT1 may be a relevant predictive marker of benefit from gemcitabine-based therapies in patients with advanced BTC.

High-resolution melting analysis of sequence variations in the cytidine deaminase gene (CDA) in patients with cancer treated with gemcitabine.

PubMed

Raynal, Caroline; Ciccolini, Joseph; Mercier, Cédric; Boyer, Jean-Christophe; Polge, Anne; Lallemant, Benjamin; Mouzat, Kévin; Lumbroso, Serge; Brouillet, Jean-Paul; Evrard, Alexandre

2010-02-01

Gemcitabine (2',2'-difluorodeoxycytidine) is a major antimetabolite cytotoxic drug with a wide spectrum of activity against solid tumors. Hepatic elimination of gemcitabine depends on a catabolic pathway through a deamination step driven by the enzyme cytidine deaminase (CDA). Severe hematologic toxicity to gemcitabine was reported in patients harboring genetic polymorphisms in CDA gene. High-resolution melting (HRM) analysis of polymerase chain reaction amplicon emerges today as a powerful technique for both genotyping and gene scanning strategies. In this study, 46 DNA samples from gemcitabine-treated patients were subjected to HRM analysis on a LightCycler 480 platform. Residual serum CDA activity was assayed as a surrogate marker for the overall functionality of this enzyme. Genotyping of three well-described single nucleotide polymorphisms in coding region (c.79A>C, c.208G>A and c.435C>T) was successfully achieved by HRM analysis of small polymerase chain reaction fragments, whereas unknown single nucleotide polymorphisms were searched by a gene scanning strategy with longer amplicons (up to 622 bp). The gene scanning strategy allowed us to find a new intronic mutation c.246+37G>A in a female patient displaying marked CDA deficiency and who had an extreme toxic reaction with a fatal outcome to gemcitabine treatment. Our work demonstrates that HRM-based methods, owing to their simplicity, reliability, and speed, are useful tools for diagnosis of CDA deficiency and could be of interest for personalized medicine.

Predictive role of repair enzymes in the efficacy of Cisplatin combinations in pancreatic and lung cancer.

PubMed

Peters, Godefridus J; Avan, Abolfazl; Ruiz, Marielle Gallegos; Orsini, Vanessa; Avan, Amir; Giovannetti, Elisa; Smit, Egbert F

2014-01-01

Platinum combinations are the mainstay of treatment for non-small cell lung cancer (NSCLC), while for pancreatic cancer platinum combinations are being given to good-performance status patients. These platinum combinations consist of cis- or carboplatin with gemcitabine, while, for non-squamous NSCLC and mesothelioma, of pemetrexed. The combination of gemcitabine and cisplatin is based on gemcitabine-induced increased formation and retention of DNA-platinum adducts, which can be explained by a decrease of excision repair cross-complementing group-1 (ERCC1)-mediated DNA repair. In these patients, survival and response is prolonged when ERCC1 has a low protein or mRNA expression. A low expression of ribonucleotide reductase (RR) is related to a better treatment outcome after both gemcitabine and gemcitabine-platinum combinations. For pemetrexed combinations, ERCC1 expression was not related to survival. For both NSCLC and pancreatic cancer, polymorphisms in ERCC1 (C118T) and Xeroderma pigmentosum group D (XPD) (A751C) were related to survival. In currently ongoing and future prospective studies, patients should be selected based on their DNA repair status, but it still has to be determined whether this should be by immunohistochemistry, mRNA expression, or a polymorphism.

Gemcitabine Injection

MedlinePlus

... other chemotherapy drugs to treat a type of lung cancer (non-small cell lung cancer; NSCLC) that has spread to other parts of ... 3 weeks. When gemcitabine is used to treat lung cancer it is usually given on certain days every ...

Health-related quality of life of adjuvant chemotherapy with S-1 versus gemcitabine for resected pancreatic cancer: Results from a randomised phase III trial (JASPAC 01).

PubMed

Hagiwara, Yasuhiro; Ohashi, Yasuo; Uesaka, Katsuhiko; Boku, Narikazu; Fukutomi, Akira; Okamura, Yukiyasu; Konishi, Masaru; Matsumoto, Ippei; Kaneoka, Yuji; Shimizu, Yasuhiro; Nakamori, Shoji; Sakamoto, Hirohiko; Morinaga, Soichiro; Kainuma, Osamu; Imai, Koji; Sata, Naohiro; Hishinuma, Shoichi; Ojima, Hitoshi; Yamaguchi, Ryuzo; Hirano, Satoshi; Sudo, Takeshi

2018-04-01

Adjuvant chemotherapy with S-1 for resected pancreatic cancer demonstrated survival benefits compared with gemcitabine in the JASPAC 01 trial. We investigated the effect of these agents on health-related quality of life (HRQOL) of patients in the JASPAC 01 trial. Patients with resected pancreatic cancer were randomly assigned to receive gemcitabine (1000 mg/m 2 weekly for three of four weeks for up to six cycles) or S-1 (40, 50, or 60 mg twice daily for four of six weeks for up to four cycles). HRQOL was assessed using the EuroQol-5D-3L (EQ-5D) questionnaire at baseline, months three and six, and every 6 months thereafter. HRQOL end-points included change in EQ-5D index from baseline, responses to five items in the EQ-5D, and quality-adjusted life months up to 24 months. Of randomised 385 patients, 354 patients were included in HRQOL analysis. Mean change in the EQ-5D index was similar in the S-1 and gemcitabine groups within 6 months from treatment initiation (difference, 0.024; P = 0.112), whereas corresponding mean from 12 to 24 months was better in the S-1 group than in the gemcitabine group (difference, 0.071; P < 0.001). Problems in mobility and pain/discomfort were also less frequent in the S-1 group than in the gemcitabine group in that period. Quality-adjusted life months were longer in the S-1 group than in the gemcitabine group (P < 0.001). Adjuvant chemotherapy with S-1 does not improve HRQOL within 6 months from treatment initiation but does improve HRQOL thereafter and quality-adjusted life months. UMIN000000655 at UMIN CTR. Copyright © 2018 Elsevier Ltd. All rights reserved.

The contribution of DNA replication stress marked by high-intensity, pan-nuclear γH2AX staining to chemosensitization by CHK1 and WEE1 inhibitors.

PubMed

Parsels, Leslie A; Parsels, Joshua D; Tanska, Daria M; Maybaum, Jonathan; Lawrence, Theodore S; Morgan, Meredith A

2018-06-12

Small molecule inhibitors of the checkpoint proteins CHK1 and WEE1 are currently in clinical development in combination with the antimetabolite gemcitabine. It is unclear, however, if there is a therapeutic advantage to CHK1 vs. WEE1 inhibition for chemosensitization. The goals of this study were to directly compare the relative efficacies of the CHK1 inhibitor MK8776 and the WEE1 inhibitor AZD1775 to sensitize pancreatic cancer cell lines to gemcitabine and to identify pharmacodynamic biomarkers predictive of chemosensitization. Cells treated with gemcitabine and either MK8776 or AZD1775 were first assessed for clonogenic survival. With the exception of the homologous recombination-defective Capan1 cells, which were relatively insensitive to MK8776, we found that these cell lines were similarly sensitized to gemcitabine by CHK1 or WEE1 inhibition. The abilities of either the CDK1/2 inhibitor roscovitine or exogenous nucleosides to prevent MK8776 or AZD1775-mediated chemosensitization, however, were both inhibitor-dependent and variable among cell lines. Given the importance of DNA replication stress to gemcitabine chemosensitization, we next assessed high-intensity, pan-nuclear γH2AX staining as a pharmacodynamic marker for sensitization. In contrast to total γH2AX, aberrant mitotic entry or sub-G1 DNA content, high-intensity γH2AX staining correlated with chemosensitization by either MK8776 or AZD1775 (R 2 0.83 - 0.53). In summary, we found that MK8776 and AZD1775 sensitize to gemcitabine with similar efficacy. Furthermore, our results suggest that the effects of CHK1 and WEE1 inhibition on gemcitabine-mediated replication stress best predict chemosensitization and support the use of high-intensity or pan-nuclear γH2AX staining as a marker for therapeutic response.

CONKO-005: Adjuvant Chemotherapy With Gemcitabine Plus Erlotinib Versus Gemcitabine Alone in Patients After R0 Resection of Pancreatic Cancer: A Multicenter Randomized Phase III Trial.

PubMed

Sinn, Marianne; Bahra, Marcus; Liersch, Torsten; Gellert, Klaus; Messmann, Helmut; Bechstein, Wolf; Waldschmidt, Dirk; Jacobasch, Lutz; Wilhelm, Martin; Rau, Bettina M; Grützmann, Robert; Weinmann, Arndt; Maschmeyer, Georg; Pelzer, Uwe; Stieler, Jens M; Striefler, Jana K; Ghadimi, Michael; Bischoff, Sven; Dörken, Bernd; Oettle, Helmut; Riess, Hanno

2017-10-10

Purpose Gemcitabine is standard of care in the adjuvant treatment of resectable pancreatic ductal adenocarcinoma (PDAC). The epidermal growth factor receptor tyrosine kinase inhibitor erlotinib in combination with gemcitabine has shown efficacy in the treatment of advanced PDAC and was considered to improve survival in patients with primarily resectable PDAC after R0 resection. Patients and Methods In an open-label, multicenter trial, patients were randomly assigned to one of two study arms: gemcitabine 1,000 mg/m 2 days 1, 8, 15, every 4 weeks plus erlotinib 100 mg once per day (GemErlo) or gemcitabine (Gem) alone for six cycles. The primary end point of the study was to improve disease-free survival (DFS) from 14 to 18 months by adding erlotinib to gemcitabine. Results In all, 436 patients were randomly assigned at 57 study centers between April 2008 and July 2013. A total of 361 instances (83%) of disease recurrence were observed after a median follow-up of 54 months. Median treatment duration was 22 weeks in both arms. There was no difference in median DFS (GemErlo 11.4 months; Gem 11.4 months) or median overall survival (GemErlo 24.5 months; Gem 26.5 months). There was a trend toward long-term survival in favor of GemErlo (estimated survival after 1, 2, and 5 years for GemErlo was 77%, 53%, and 25% v 79%, 54%, and 20% for Gem, respectively). The occurrence or the grade of rash was not associated with a better survival in the GemErlo arm. Conclusion To the best of our knowledge, CONKO-005 is the first study to investigate the combination of chemotherapy and a targeted therapy in the adjuvant treatment of PDAC. GemErlo for 24 weeks did not improve DFS or overall survival over Gem.

SELECT-3: a phase I study of selumetinib in combination with platinum-doublet chemotherapy for advanced NSCLC in the first-line setting

PubMed Central

Greystoke, Alastair; Steele, Nicola; Arkenau, Hendrik-Tobias; Blackhall, Fiona; Md Haris, Noor; Lindsay, Colin R; Califano, Raffaele; Voskoboynik, Mark; Summers, Yvonne; So, Karen; Ghiorghiu, Dana; Dymond, Angela W; Hossack, Stuart; Plummer, Ruth; Dean, Emma

2017-01-01

Background: We investigated selumetinib (AZD6244, ARRY-142886), an oral, potent, and highly selective, allosteric MEK1/2 inhibitor, plus platinum-doublet chemotherapy for patients with advanced/metastatic non-small cell lung cancer. Methods: In this Phase I, open-label study (NCT01809210), treatment-naïve patients received selumetinib (50, 75, 100 mg BID PO) plus standard doses of gemcitabine or pemetrexed plus cisplatin or carboplatin. Primary objectives were safety, tolerability, and determination of recommended Phase II doses. Results: Fifty-five patients received treatment: selumetinib 50 or 75 mg plus gemcitabine/cisplatin (n=10); selumetinib 50 mg plus gemcitabine/carboplatin (n=9); selumetinib 50, 75 or 100 mg plus pemetrexed/carboplatin (n=21); selumetinib 75 mg plus pemetrexed/cisplatin (n=15). Most frequent adverse events (AEs) were fatigue, nausea, diarrhoea and vomiting. Grade ⩾3 selumetinib-related AEs were reported in 30 (55%) patients. Dose-limiting toxicities (all n=1) were Grade 4 anaemia (selumetinib 75 mg plus gemcitabine/cisplatin), Grade 4 thrombocytopenia/epistaxis and Grade 4 thrombocytopenia (selumetinib 50 mg plus gemcitabine/carboplatin), Grade 4 febrile neutropenia (selumetinib 100 mg plus pemetrexed/carboplatin), and Grade 3 lethargy (selumetinib 75 mg plus pemetrexed/cisplatin). Partial responses were confirmed in 11 (20%) and unconfirmed in 9 (16%) patients. Conclusions: Standard doses of pemetrexed/carboplatin or pemetrexed/cisplatin were tolerated with selumetinib 75 mg BID. The selumetinib plus gemcitabine-containing regimens were not tolerated. PMID:28950288

Pharmacodynamic Modeling of Cell Cycle Effects for Gemcitabine and Trabectedin Combinations in Pancreatic Cancer Cells

PubMed Central

Miao, Xin; Koch, Gilbert; Ait-Oudhia, Sihem; Straubinger, Robert M.; Jusko, William J.

2016-01-01

Combinations of gemcitabine and trabectedin exert modest synergistic cytotoxic effects on two pancreatic cancer cell lines. Here, systems pharmacodynamic (PD) models that integrate cellular response data and extend a prototype model framework were developed to characterize dynamic changes in cell cycle phases of cancer cell subpopulations in response to gemcitabine and trabectedin as single agents and in combination. Extensive experimental data were obtained for two pancreatic cancer cell lines (MiaPaCa-2 and BxPC-3), including cell proliferation rates over 0–120 h of drug exposure, and the fraction of cells in different cell cycle phases or apoptosis. Cell cycle analysis demonstrated that gemcitabine induced cell cycle arrest in S phase, and trabectedin induced transient cell cycle arrest in S phase that progressed to G2/M phase. Over time, cells in the control group accumulated in G0/G1 phase. Systems cell cycle models were developed based on observed mechanisms and were used to characterize both cell proliferation and cell numbers in the sub G1, G0/G1, S, and G2/M phases in the control and drug-treated groups. The proposed mathematical models captured well both single and joint effects of gemcitabine and trabectedin. Interaction parameters were applied to quantify unexplainable drug-drug interaction effects on cell cycle arrest in S phase and in inducing apoptosis. The developed models were able to identify and quantify the different underlying interactions between gemcitabine and trabectedin, and captured well our large datasets in the dimensions of time, drug concentrations, and cellular subpopulations. PMID:27895579

Wilms tumor gene (WT1) peptide-based cancer vaccine combined with gemcitabine for patients with advanced pancreatic cancer.

PubMed

Nishida, Sumiyuki; Koido, Shigeo; Takeda, Yutaka; Homma, Sadamu; Komita, Hideo; Takahara, Akitaka; Morita, Satoshi; Ito, Toshinori; Morimoto, Soyoko; Hara, Kazuma; Tsuboi, Akihiro; Oka, Yoshihiro; Yanagisawa, Satoru; Toyama, Yoichi; Ikegami, Masahiro; Kitagawa, Toru; Eguchi, Hidetoshi; Wada, Hiroshi; Nagano, Hiroaki; Nakata, Jun; Nakae, Yoshiki; Hosen, Naoki; Oji, Yusuke; Tanaka, Toshio; Kawase, Ichiro; Kumanogoh, Atsushi; Sakamoto, Junichi; Doki, Yuichiro; Mori, Masaki; Ohkusa, Toshifumi; Tajiri, Hisao; Sugiyama, Haruo

2014-01-01

Wilms tumor gene (WT1) protein is an attractive target for cancer immunotherapy. We aimed to investigate the feasibility of a combination therapy consisting of gemcitabine and WT1 peptide-based vaccine for patients with advanced pancreatic cancer and to make initial assessments of its clinical efficacy and immunologic response. Thirty-two HLA-A*24:02 patients with advanced pancreatic cancer were enrolled. Patients received HLA-A*24:02-restricted, modified 9-mer WT1 peptide (3 mg/body) emulsified with Montanide ISA51 adjuvant (WT1 vaccine) intradermally biweekly and gemcitabine (1000 mg/m) on days 1, 8, and 15 of a 28-day cycle. This combination therapy was well tolerated. The frequencies of grade 3-4 adverse events for this combination therapy were similar to those for gemcitabine alone. Objective response rate was 20.0% (6/30 evaluable patients). Median survival time and 1-year survival rate were 8.1 months and 29%, respectively. The association between longer survival and positive delayed-type hypersensitivity to WT1 peptide was statistically significant, and longer survivors featured a higher frequency of memory-phenotype WT1-specific cytotoxic T lymphocytes both before and after treatment. WT1 vaccine in combination with gemcitabine was well tolerated for patients with advanced pancreatic cancer. Delayed-type hypersensitivity-positivity to WT1 peptide and a higher frequency of memory-phenotype WT1-specific cytotoxic T lymphocytes could be useful prognostic markers for survival in the combination therapy with gemcitabine and WT1 vaccine. Further clinical investigation is warranted to determine the effectiveness of this combination therapy.

Blockade of vascular endothelial growth factor receptor and epidermal growth factor receptor signaling for therapy of metastatic human pancreatic cancer.

PubMed

Baker, Cheryl H; Solorzano, Carmen C; Fidler, Isaiah J

2002-04-01

We determined whether concurrent blockage of vascular endothelial growth factor (VEGF) receptor and epidermal growth factor (EGF) receptor signaling by two novel tyrosine kinase inhibitors, PTK 787 and PKI 166, respectively, can inhibit angiogenesis and, hence, the growth and metastasis of human pancreatic carcinoma in nude mice. Highly metastatic human pancreatic carcinoma L3.6pl cells were injected into the pancreas of nude mice. Seven days later, groups of mice began receiving oral doses of PTK 787 and PKI 166 three times weekly. Some groups of mice also received i.p. injections of gemcitabine twice a week. The mice were necropsied when the control mice became moribund. Treatment with PTK 787 and PKI 166, with gemcitabine alone, or with the combination of PTK 787, PKI 166, and gemcitabine produced 69, 50, and 97% reduction in the volume of pancreatic tumors, respectively. Administration of protein tyrosine kinase inhibitors and gemcitabine also significantly decreased the incidence of lymph node and liver metastasis. The therapeutic efficacy directly correlated with a decrease in circulating proangiogenic molecules (VEGF, interleukin-8), a decrease in microvessel density, a decrease in proliferating cell nuclear antigen staining, and an increase in apoptosis of tumor cells and endothelial cells. Therapies produced by combining gemcitabine with either PKI 166 or PTK 787 were similar to those produced by combining gemcitabine with both PKI 166 and PTK 787. These results suggest that blockade of either epidermal growth factor receptor or VEGF receptor signaling combined with chemotherapy provides an effective approach to the therapy of pancreatic cancer.

Cost description of chemotherapy regimens for the treatment of metastatic pancreas cancer.

PubMed

Goldstein, Daniel A; Krishna, Kavya; Flowers, Christopher R; El-Rayes, Bassel F; Bekaii-Saab, Tanios; Noonan, Anne M

2016-05-01

Multiple chemotherapy regimens are available for the treatment of metastatic pancreas cancer (mPCA). Choice of regimen is based on the patient's performance status and toxicity profile of the regimen. The objective of this study was to analyze the costs of first-line regimens to further aid in decision-making and develop a platform upon which to assess value. We calculated the monthly cost for individual standard regimens (gemcitabine, gemcitabine/nab-paclitaxel, gemcitabine/erlotinib and FOLFIRINOX) and the overall treatment cost for a course of therapy based on the median progression-free survival achieved in published studies. In addition to cost of drugs, we included administration costs and costs of toxicities (including growth factor support, blood product transfusion and hospitalization for toxicities). Costs for administration and management of adverse events were based on Medicare reimbursement rates for hospital and physician services. Drug costs were based on Medicare average sale prices (all 2014 US$). The monthly costs for gemcitabine, FOLFIRINOX, gemcitabine/erlotinib and gemcitabine/nab-paclitaxel were $1363, $7234, $8007 and $12,221, respectively. The overall treatment costs for a course of the same regimens based on median PFS were $5043, $46,298, $51,004 and $67,216, respectively. The choice of chemotherapy regimen for mPCA should be based on tolerability and efficacy of the regimen individualized to patient's performance status. Healthcare systems have finite resources; thus, there is increasing emphasis on metrics to define value in health care when outcomes of therapy are similar or produce marked differences in value. These data provide useful financial information to incorporate into the decision-making process.

Alternation in the gap-junctional intercellular communication capacity during the maturation of osteocytes in the embryonic chick calvaria.

PubMed

Wang, Ziyi; Odagaki, Naoya; Tanaka, Tomoyo; Hashimoto, Mana; Nakamura, Masahiro; Hayano, Satoru; Ishihara, Yoshihito; Kawanabe, Noriaki; Kamioka, Hiroshi

2016-10-01

The intercellular network of cell-cell communication among osteocytes is mediated by gap junctions. Gap junctional intercellular communication (GJIC) is thought to play an important role in the integration and synchronization of bone remodeling. To further understand the mechanism of bone development it is important to quantify the difference in the GJIC capacity of young and developmentally mature osteocytes. We first established an embryonic chick calvaria growth model to show the growth of the calvaria in embryos at 13 to 21days of age. We then applied a fluorescence recovery after photobleaching (FRAP) technique to compare the difference in the GJIC capacity of young osteocytes with that of developmentally mature osteocytes. Finally, we quantified the dye (Calcein) diffusion from the FRAP data using a mathematic model of simple diffusion which was also used to identify simple diffusion GJIC pattern cells (fitted model) and accelerated diffusion GJIC pattern cells (non-fitted model). The relationship between the longest medial-lateral length of the calvaria (frontal bone) and the embryonic age fit a logarithmic growth model: length=5.144×ln(day)-11.340. The morphometric data during osteocyte differentiation showed that the cellular body becomes more spindle-shaped and that the cell body volume decreased by approximately 22% with an increase in the length of the processes between the cells. However, there were no significant differences in the cellular body surface area or in the distance between the mass centres of the cells. The dye-displacement rate in young osteocytes was significantly higher than that in developmentally mature osteocytes: dye displacement only occurred in 26.88% of the developmentally mature osteocytes, while it occurred in 64.38% of the young osteocytes. Additionally, in all recovered osteocytes, 36% of the developmentally mature osteocytes comprised non-fitted model cells while 53.19% of the young osteocytes were the non-fitted model, which indicates the active transduction of dye molecules. However, there were no statistically significant differences between the young and developmentally mature osteocytes with regard to the diffusion coefficient, permeability coefficient, or permeance of the osteocyte processes, which were 3.93±3.77 (×10(-8)cm(2)/s), 5.12±4.56 (×10(-5)cm(2)/s) and 2.99±2.47 (×10(-13)cm(2)/s) (mean±SD), respectively. These experiments comprehensively quantified the GJIC capacity in the embryonic chick calvaria and indicated that the cell-cell communication capacity of the osteocytes in the embryonic chick calvaria was related to their development. Copyright © 2016 Elsevier Inc. All rights reserved.

Gemcitabine-loaded albumin nanospheres (GEM-ANPs) inhibit PANC-1 cells in vitro and in vivo

NASA Astrophysics Data System (ADS)

Li, Ji; Di, Yang; Jin, Chen; Fu, Deliang; Yang, Feng; Jiang, Yongjian; Yao, Lie; Hao, Sijie; Wang, Xiaoyi; Subedi, Sabin; Ni, Quanxing

2013-04-01

With the development of nanotechnology, special attention has been given to the nanomaterial application in tumor treatment. Here, a modified desolvation-cross-linking method was successfully applied to fabricate gemcitabine-loaded albumin nanospheres (GEM-ANPs), with 110 and 406 nm of mean diameter, respectively. The aim of this study was to assess the drug distribution, side effects, and antitumor activity of GEM-ANPs in vivo. The metabolic viability and flow cytometry analysis revealed that both GEM-ANPs, especially 406-nm GEM-ANPs, could effectively inhibit the metabolism and proliferation and promote the apoptosis of human pancreatic carcinoma (PANC-1) in vitro. Intravenous injection of 406-nm GEM-ANPs exhibited a significant increase of gemcitabine in the pancreas, liver, and spleen of Sprague-Dawley rats ( p < 0.05). Moreover, no signs of toxic side effects analyzed by blood parameter changes were observed after 3 weeks of administration although a high dose (200 mg/kg) of GEM-ANPs were used. Additionally, in PANC-1-induced tumor mice, intravenous injection of 406-nm GEM-ANPs also could effectively reduce the tumor volume by comparison with free gemcitabine. With these findings, albumin nanosphere-loading approach might be efficacious to improve the antitumor activity of gemcitabine, and the efficacy is associated with the size of GEM-ANPs.

A carbon nanotube-gemcitabine-lentinan three-component composite for chemo-photothermal synergistic therapy of cancer.

PubMed

Zhang, Ping; Yi, Wenhui; Hou, Jin; Yoo, Sweejiang; Jin, Weiqiu; Yang, Qisheng

2018-01-01

Gemcitabine's clinical application is limited due to its short plasma half-life and poor uptake by cells. To address this problem, a drug delivery three-component composite, multiwalled carbon nanotubes (MWNTs)/gemcitabine (Ge)/lentinan (Le; MWNTs-Ge-Le), was fabricated in our study. Moreover, the combination of chemotherapy and photothermal therapy was employed to enhance antitumor efficacy. In this study, we conjugated gemcitabine and lentinan with MWNTs via a covalent and noncovalent way to functionalize with MWNTs, and the chemical structure of MWNTs-Ge-Le was characterized by Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis and transmission electron microscopy. Using the composite and an 808 nm laser, we treated tumors, both in vitro and in vivo, and investigated the photothermal responses and the anticancer efficacy. The MWNTs-Ge-Le composite could efficiently cross cell membrane, having a higher antitumor activity than MWNTs, gemcitabine and MWNTs-Ge in vitro and in vivo. Our study on the MWNTs-Ge-Le composite with an 808 nm laser radiation showed the combination of drug therapy and near-infrared photothermal therapy possesses great synergistic antitumor efficacy. The MWNTs-Ge-Le three-component anticancer composite can serve as a promising candidate for cancer therapy in the combination of chemotherapy and photothermal therapy.

Alterations in Pharmacokinetics of Gemcitabine and Erlotinib by Concurrent Administration of Hyangsayukgunja-Tang, a Gastroprotective Herbal Medicine.

PubMed

Kim, Tae Hwan; Shin, Soyoung; Kim, Sarah; Bulitta, Jürgen B; Weon, Kwon-Yeon; Joo, Sang Hoon; Ma, Eunsook; Yoo, Sun Dong; Park, Gi-Young; Kwon, Dong Rak; Jeong, Seok Won; Lee, Da Young; Shin, Beom Soo

2017-09-10

Gemcitabine and erlotinib are the chemotherapeutic agents used in the treatment of various cancers and their combination is being accepted as a first-line treatment of advanced pancreatic cancer. Hyangsayukgunja-tang (HYT) is a traditional oriental medicine used in various digestive disorders and potentially helpful to treat gastrointestinal adverse effects related to chemotherapy. The present study was aimed to evaluate the effect of HYT on the pharmacokinetics of gemcitabine and erlotinib given simultaneously in rats. Rats were pretreated with HYT at an oral dose of 1200 mg/kg/day once daily for a single day or 14 consecutive days. Immediately after pretreatment with HYT, gemcitabine and erlotinib were administered by intravenous injection (10 mg/kg) and oral administration (20 mg/kg), respectively. The effects of HYT on pharmacokinetics of the two drugs were estimated by non-compartmental analysis and pharmacokinetic modeling. The pharmacokinetics of gemcitabine and erlotinib were not altered by single dose HYT pretreatment. However, the plasma levels of OSI-420 and OSI-413, active metabolites of erlotinib, were significantly decreased in the multiple dose HYT pretreatment group. The pharmacokinetic model estimated increased systemic clearances of OSI-420 and OSI-413 by multiple doses of HYT. These data suggest that HYT may affect the elimination of OSI-420 and OSI-413.

Ultra-sensitive LC-MS/MS method for the quantification of gemcitabine and its metabolite 2',2'-difluorodeoxyuridine in human plasma for a microdose clinical trial.

PubMed

van Nuland, M; Hillebrand, M J X; Rosing, H; Burgers, J A; Schellens, J H M; Beijnen, J H

2018-03-20

In microdose clinical trials a maximum of 100 μg of drug substance is administered to participants, in order to determine the pharmacokinetic properties of the agents. Measuring low plasma concentrations after administration of a microdose is challenging and requires the use of ulta-sensitive equipment. Novel liquid chromatography-mass spectrometry (LC-MS/MS) platforms can be used for quantification of low drug plasma levels. Here we describe the development and validation of an LC-MS/MS method for quantification of gemcitabine and its metabolite 2',2'-difluorodeoxyuridine (dFdU) in the low picogram per milliliter range to support a microdose trial. The validated assay ranges from 2.5-500 pg/mL for gemcitabine and 250-50,000 pg/mL for dFdU were linear, with a correlation coefficient (r 2 ) of 0.996 or better. Sample preparation with solid phase extraction provided a good and reproducible recovery. All results were within the acceptance criteria of the latest US FDA guidance and EMA guidelines. In addition, the method was successfully applied to measure plasma concentrations of gemcitabine in a patient after administration of a microdose of gemcitabine. Copyright © 2017 Elsevier B.V. All rights reserved.

Cost Effectiveness Analysis of Different Management Strategies between Best Supportive Care and Second-line Chemotherapy for Platinum-resistant or Refractory Ovarian Cancer.

PubMed

Luealon, Phanida; Khempech, Nipon; Vasuratna, Apichai; Hanvoravongchai, Piya; Havanond, Piyalamporn

2016-01-01

There is no standard treatment for patients with platinum-resistant or refractory epithelial ovarian cancer. Single agent chemotherapies have evidence of more efficacy and less toxicity than combination therapy. Most are very expensive, with appreciable toxicity and minimal survival. Since it is difficult to make comparison between outcomes, economic analysis of single-agent chemotherapy regimens and best supportive care may help to make decisions about an appropriate management for the affected patients. To evaluate the cost effectiveness of second-line chemotherapy compared with best supportive care for patients with platinum-resistant or refractory epithelial ovarian cancer. A Markov model was used to estimate the effectiveness and total costs associated with treatments. The hypothetical patient population comprised women aged 55 with platinum-resistant or refractory epithelial ovarian cancer. Four types of alternative treatment options were evaluated: 1) gemcitabine followed by BSC; 2) pegylated liposomal doxorubicin (PLD) followed by BSC; 3) gemcitabine followed by topotecan; and 4) PLD followed by topotecan. Baseline comparator of alternative treatments was BSC. Time horizon of the analysis was 2 years. Health care provider perspective and 3% discount rate were used to determine the costs of medical treatment in this study. Quality-adjusted life-years (QALY) were used to measure the treatment effectiveness. Treatment effectiveness data were derived from the literature. Costs were calculated from unit cost treatment of epithelial ovarian cancer patients at various stages of disease in King Chulalongkorn Memorial Hospital (KCMH) in the year 2011. Parameter uncertainty was tested in probabilistic sensitivity analysis by using Monte Carlo simulation. One-way sensitivity analysis was used to explore each variable's impact on the uncertainty of the results. Approximated life expectancy of best supportive care was 0.182 years and its total cost was 26,862 Baht. All four alternative treatments increased life expectancy. Life expectancy of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 0.510, 0.513, 0.566, and 0.570 years, respectively. The total cost of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 113,000, 124,302, 139,788 and 151,135 Baht, respectively. PLD followed by topotecan had the highest expected quality-adjusted life-years but was the most expensive of all the above strategies. The incremental cost-effectiveness ratios (ICER) of gemcitabine followed by BSC, PLD followed by BSC, gemcitabine followed by topotecan and PLD followed by topotecan was 344,643, 385,322, 385,856, and 420,299 Baht, respectively. All of the second-line chemotherapy strategies showed certain benefits due to an increased life- year gained compared with best supportive care. Moreover, gemcitabine as second-line chemotherapy followed by best supportive care in progressive disease case was likely to be more effective strategy with less cost from health care provider perspective. Gemcitabine was the most cost-effective treatment among all four alternative treatments. ICER is only an economic factor. Treatment decisions should be based on the patient benefit.

Long-range intercellular Ca2+ wave patterns

NASA Astrophysics Data System (ADS)

Tabi, C. B.; Maïna, I.; Mohamadou, A.; Ekobena, H. P. F.; Kofané, T. C.

2015-10-01

Modulational instability is utilized to investigate intercellular Ca2+ wave propagation in an array of diffusively coupled cells. Cells are supposed to be connected via paracrine signaling, where long-range effects, due to the presence of extracellular messengers, are included. The multiple-scale expansion is used to show that the whole dynamics of Ca2+ waves, from the endoplasmic reticulum to the cytosol, can be reduced to a single differential-difference nonlinear equation whose solutions are assumed to be plane waves. Their linear stability analysis is studied, with emphasis on the impact of long-range coupling, via the range parameter s. It is shown that s, as well as the number of interacting cells, importantly modifies the features of modulational instability, as small values of s imply a strong coupling, and increasing its value rather reduces the problem to a first-neighbor one. Our theoretical findings are numerically tested, as the generic equations are fully integrated, leading to the emergence of nonlinear patterns of Ca2+ waves. Strong long-range coupling is pictured by extended trains of breather-like structures whose frequency decreases with increasing s. We also show numerically that the number of interacting cells plays on the spatio-temporal formation of Ca2+ patterns, whilst the quasi-perfect intercellular communication depends on the paracrine coupling parameter.

ADAM15 is involved in MICB shedding and mediates the effects of gemcitabine on MICB shedding in PANC-1 pancreatic cancer cells.

PubMed

Duan, Xiaohui; Mao, Xianhai; Sun, Weijia

2013-03-01

The aim of this study was to investigate the role of ADAM15 in MHC class I polypeptide-related sequence B (MICB) protein ectodomain shedding and observe whether or not gemcitabine affects MICB shedding from PANC-1 cells. In this study, immunohistochemistry of MICB and ADAM15 were performed on tumor samples obtained from 93 patients with pancreatic ductal adenocarcinoma (PDAC). The expression of MICB and ADAM15 in the PDAC tissues was significantly higher compared with that in the normal tissues of the pancreas. Statistical analysis showed a significant correlation between the expression of MICB and certain classic clinicopathological characteristics (i.e., histological grade and TNM stage). ADAM15 expression was found to correlate with lymph node metastasis and TNM stage. The Spearman's rank test suggested that the expression of MICB was inversely correlated with that of ADAM15 in PDAC tissues. Knockdown of ADAM15 in PANC-1 cells clearly upregulated MICB expression on the cellular surface and downregulated soluble MICB (sMICB) levels in the culture supernatants. A non-toxic dose of 0.5 µmol/l gemcitabine suppresses ADAM15 expression leading, at the same time, to an increase in MICB expression and a decrease in sMICB production in PANC-1 cells. The mRNA levels of MICB did not change following PANC-1 exposure to gemcitabine. Further study suggests that the suppressive effect of gemcitabine on MICB shedding in PANC-1 cells is mediated by ADAM15 downregulation. In conclusion, the results of the present study support the hypothesis that ADAM15 is involved in MICB shedding of PANC-1 cells and that gemcitabine inhibits MICB ectodomain shedding through the suppression of ADAM15.

Bitter melon juice targets molecular mechanisms underlying gemcitabine resistance in pancreatic cancer cells.

PubMed

Somasagara, Ranganatha R; Deep, Gagan; Shrotriya, Sangeeta; Patel, Manisha; Agarwal, Chapla; Agarwal, Rajesh

2015-04-01

Pancreatic cancer (PanC) is one of the most lethal malignancies, and resistance towards gemcitabine, the front-line chemotherapy, is the main cause for dismal rate of survival in PanC patients; overcoming this resistance remains a major challenge to treat this deadly malignancy. Whereas several molecular mechanisms are known for gemcitabine resistance in PanC cells, altered metabolism and bioenergetics are not yet studied. Here, we compared metabolic and bioenergetic functions between gemcitabine-resistant (GR) and gemcitabine-sensitive (GS) PanC cells and underlying molecular mechanisms, together with efficacy of a natural agent bitter melon juice (BMJ). GR PanC cells showed distinct morphological features including spindle-shaped morphology and a decrease in E-cadherin expression. GR cells also showed higher ATP production with an increase in oxygen consumption rate (OCR) and extracellular acidification rate (ECAR). Molecular studies showed higher expression of glucose transporters (GLUT1 and 4) suggesting an increase in glucose uptake by GR cells. Importantly, GR cells showed a significant increase in Akt and ERK1/2 phosphorylation and their inhibition decreased cell viability, suggesting their role in survival and drug resistance of these cells. Recently, we reported strong efficacy of BMJ against a panel of GS cells in culture and nude mice, which we expanded here and found that BMJ was also effective in decreasing both Akt and ERK1/2 phosphorylation and viability of GR PanC cells. Overall, we have identified novel mechanisms of gemcitabine resistance in PanC cells which are targeted by BMJ. Considering the short survival in PanC patients, our findings could have high translational potential in controlling this deadly malignancy.

Palliative chemotherapy with gemcitabine, paclitaxel, and cisplatin as first-line treatment following gemcitabine monotherapy for patients with transitional cell carcinoma of the urothelium.

PubMed

Ecke, T H; Gerullis, H; Bartel, P; Koch, S; Ruttloff, J

2009-03-01

Chemotherapeutic agents are active in transitional cell cancer of the urothelium, and combinations have shown promising results. The objective of this study was to evaluate the palliative chemotherapy with gemcitabine, paclitaxel, and cisplatin for transitional cell carcinoma. Thirty-four patients with advanced transitional cell carcinoma of the urothelium were treated between 2000 and 2007. All patients received chemotherapy with intravenous gemcitabine at a dose of 1000 mg/m2 on days I and VIII, intravenous paclitaxel at a dose of 80 mg/m2 on days I and VIII, and intravenous cisplatin at a dose of 50 mg/m2 on day II. Treatment courses were repeated every 21 days. After completion of four to six courses in this regimen an application of intravenous gemcitabine at a dose of 1000 mg/m2 followed repeating every 28 days. Twelve patients (35.3%) had 1 visceral sites of metastases. Twenty two patients (64.7%) had achieved objective responses to treatment (29.4% complete responses). The median actuarial survival was 18.5 months, and the actuarial one-year and two-year survival rates were 56% and 26% respectively. After a median follow-up of 16.3 months, 18 patients remained alive. The median progression-free survival was 7 months. Median survival time for patients with ECOG status 0, 1, and 2 was 45, 12, and 10.5 months respectively. Grade 3-4 neutropenia occurred in 41.2% of patients. The combination of gemcitabine, paclitaxel, and cisplatin is a highly effective and tolerable regimen for patients with advanced transitional cell carcinoma of the urothelium. This treatment should be considered as a suitable option that deserves further prospective evaluation. ECOG performance status and visceral metastases are important predictive factors for survival.

Gemcitabine plus cisplatin versus gemcitabine plus carboplatin as first-line chemotherapy in advanced transitional cell carcinoma of the urothelium: results of a randomized phase 2 trial.

PubMed

Dogliotti, Luigi; Cartenì, Giacomo; Siena, Salvatore; Bertetto, Oscar; Martoni, Andrea; Bono, Aldo; Amadori, Dino; Onat, Haluk; Marini, Luca

2007-07-01

This phase 2 randomized study compared the toxicity and assessed the efficacy of gemcitabine-cisplatin (GP) and gemcitabine-carboplatin (GC) in patients with advanced transitional cell carcinoma of the urothelium (TCC), with the main objective to demonstrate a reduction in toxicity of at least 25% in the GC arm. A total of 110 chemonaive patients (55 per arm) with locally advanced or metastatic TCC received gemcitabine 1250 mg/m(2) on days 1 and 8 plus cisplatin 70 mg/m(2) on day 2 (GP) every 3 wk or gemcitabine 1250 mg/m(2) on days 1 and 8 plus carboplatin AUC 5 on day 2 (GC) every 3 wk for a maximum of six cycles. No differences between arms were noted in the overall toxicity profiles and any parameter of toxicity. The most frequent grade 3-4 hematologic toxicity was neutropenia in 34.6% of patients for GP and 45.4% for GC. The most frequent grade 3-4 nonhematologic toxicity was nausea and vomiting (GP: 9.1%; GC: 3.6%). Grade 1-2 nephrotoxicity occurred in 14 GP-treated patients (26.0%) and 9 GC-treated patients (16.3%). Per an intent-to-treat analysis, overall response, evaluated on 80 patients, was 49.1% for GP (CR: 14.5%; PR: 34.5%) and 40.0% for GC (CR: 1.8%; PR: 38.2%). Median time to progression was 8.3 mo for GP and 7.7 mo for GC. Median survival was 12.8 mo and 9.8 mo for GP and GC, respectively. GC has a comparably acceptable toxicity profile compared with that of GP and seems active in patients with TCC.

Stereotactic body radiation therapy with concurrent full-dose gemcitabine for locally advanced pancreatic cancer: a pilot trial demonstrating safety

PubMed Central

2013-01-01

Background Concurrent chemoradiation is a standard option for locally advanced pancreatic cancer (LAPC). Concurrent conventional radiation with full-dose gemcitabine has significant toxicity. Stereotactic body radiation therapy (SBRT) may provide the opportunity to administer radiation in a shorter time frame with similar efficacy and reduced toxicity. This Pilot study assessed the safety of concurrent full-dose gemcitabine with SBRT for LAPC. Methods Patients received gemcitabine, 1000 mg/m2 for 6 cycles. During week 4 of cycle 1, patients received SBRT (25 Gy delivered in five consecutive daily fractions of 5 Gy prescribed to the 75-83% isodose line). Acute and late toxicities were assessed using NIH CTCAE v3. Tumor response was assessed by RECIST. Patients underwent an esophagogastroduodenoscopy at baseline, 2, and 6 months to assess the duodenal mucosa. Quality of life (QoL) data was collected before and after treatment using the QLQ-C30 and QLQ-PAN26 questionnaires. Results Between September 2009 and February 2011, 11 patients enrolled with one withdrawal during radiation therapy. Patients had grade 1 to 2 gastrointestinal toxicity from the start of SBRT to 2 weeks after treatment. There were no grade 3 or greater radiation-related toxicities or delays for cycle 2 of gemcitabine. On endoscopy, there were no grade 2 or higher mucosal toxicities. Two patients had a partial response. The median progression free and overall survival were 6.8 and 12.2 months, respectively. Global QoL did not change between baseline and immediately after radiation treatment. Conclusions SBRT with concurrent full dose gemcitabine is safe when administered to patients with LAPC. There is no delay in administration of radiation or chemotherapy, and radiation is completed with minimal toxicity. PMID:23452509

Overexpression of heat shock protein 27 (HSP27) increases gemcitabine sensitivity in pancreatic cancer cells through S-phase arrest and apoptosis

PubMed Central

Guo, Yang; Ziesch, Andreas; Hocke, Sandra; Kampmann, Eric; Ochs, Stephanie; De Toni, Enrico N; Göke, Burkhard; Gallmeier, Eike

2015-01-01

We previously established a role for HSP27 as a predictive marker for therapeutic response towards gemcitabine in pancreatic cancer. Here, we investigate the underlying mechanisms of HSP27-mediated gemcitabine sensitivity. Utilizing a pancreatic cancer cell model with stable HSP27 overexpression, cell cycle arrest and apoptosis induction were analysed by flow cytometry, nuclear staining, immunoblotting and mitochondrial staining. Drug sensitivity studies were performed by proliferation assays. Hyperthermia was simulated using mild heat shock at 41.8°C. Upon gemcitabine treatment, HSP27-overexpressing cells displayed an early S-phase arrest subsequently followed by a strongly increased sub-G1 fraction. Apoptosis was characterized by PARP-, CASPASE 3-, CASPASE 8-, CASPASE 9- and BIM- activation along with a mitochondrial membrane potential loss. It was reversible through chemical caspase inhibition. Importantly, gemcitabine sensitivity and PARP cleavage were also elicited by heat shock-induced HSP27 overexpression, although to a smaller extent, in a panel of pancreatic cancer cell lines. Finally, HSP27-overexpressing pancreatic cancer cells displayed an increased sensitivity also towards death receptor-targeting agents, suggesting another pro-apoptotic role of HSP27 along the extrinsic apoptosis pathway. Taken together, in contrast to the well-established anti-apoptotic properties of HSP27 in cancer, our study reveals novel pro-apoptotic functions of HSP27—mediated through both the intrinsic and the extrinsic apoptotic pathways—at least in pancreatic cancer cells. HSP27 could represent a predictive marker of therapeutic response towards specific drug classes in pancreatic cancer and provides a novel molecular rationale for current clinical trials applying the combination of gemcitabine with regional hyperthermia in pancreatic cancer patients. PMID:25331547

Radiotherapy Does Not Influence the Severe Pulmonary Toxicity Observed With the Administration of Gemcitabine and Bleomycin in Patients With Advanced-Stage Hodgkin's Lymphoma Treated With the BAGCOPP Regimen: A Report by the German Hodgkin's Lymphoma Study Group

DOE Office of Scientific and Technical Information (OSTI.GOV)

Macann, Andrew; Bredenfeld, Henning; Mueller, Rolf-Peter

2008-01-01

Purpose: To evaluate the effect of radiotherapy on the severe pulmonary toxicity observed in the pilot study of BAGCOPP (bleomycin, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone, and gemcitabine) for advanced-stage Hodgkin's lymphoma. Methods and Materials: Patients with Stage III or IV Hodgkin's lymphoma or Stage IIB with risk factors participated in this single-arm, multicenter pilot study. Results: Twenty-seven patients were enrolled on the study before its premature closure as a result of the development of serious pulmonary toxicity in 8 patients. The pulmonary toxicity occurred either during or immediately after the BAGCOPP chemotherapy course. Pulmonary toxicity contributed to one early fatalitymore » but resolved in the other 7 patients after cessation of gemcitabine and bleomycin, allowing continuation of therapy. Fifteen patients received consolidative radiotherapy, including 4 who previously had pulmonary toxicity. There were no reported cases of radiation pneumonitis and no exacerbation of pulmonary symptoms in the 4 patients who had had previous pulmonary toxicity. Conclusions: The severe pulmonary toxicity observed in this study has been attributed to an interaction between gemcitabine and bleomycin. Gemcitabine (when administered without bleomycin) remains of interest in Hodgkin's lymphoma and is being incorporated into a new German Hodgkin's Lymphoma Study Group protocol that also includes consolidative radiotherapy. This study supports the concept of the integration of radiotherapy in gemcitabine-containing regimens in Hodgkin's lymphoma if there is an interval of at least 4 weeks between the two modalities and with a schedule whereby radiotherapy follows the chemotherapy.« less

Enzalutamide inhibits proliferation of gemcitabine-resistant bladder cancer cells with increased androgen receptor expression.

PubMed

Kameyama, Koji; Horie, Kengo; Mizutani, Kosuke; Kato, Taku; Fujita, Yasunori; Kawakami, Kyojiro; Kojima, Toshio; Miyazaki, Tatsuhiko; Deguchi, Takashi; Ito, Masafumi

2017-01-01

Advanced bladder cancer is treated mainly with gemcitabine and cisplatin, but most patients eventually become resistance. Androgen receptor (AR) signaling has been implicated in bladder cancer as well as other types of cancer including prostate cancer. In this study, we investigated the expression and role of AR in gemcitabine-resistant bladder cancer cells and also the potential of enzalutamide, an AR inhibitor, as a therapeutic for the chemoresistance. First of all, we established gemcitabine-resistant T24 cells (T24GR) from T24 bladder cancer cells and performed gene expression profiling. Microarray analysis revealed upregulation of AR expression in T24GR cells compared with T24 cells. AR mRNA and protein expression was confirmed to be increased in T24GR cells, respectively, by quantitative RT-PCR and western blot analysis, which was associated with more potent AR transcriptional activity as measured by luciferase reporter assay. The copy number of AR gene in T24GR cells determined by PCR was twice as many as that of T24 cells. AR silencing by siRNA transfection resulted in inhibition of proliferation of T24GR cells. Cell culture in charcoal-stripped serum and treatment with enzalutamide inhibited growth of T24GR cells, which was accompanied by cell cycle arrest. AR transcriptional activity was found to be reduced in T24GR cells by enzalutamide treatment. Lastly, enzalutamide also inhibited cell proliferation of HTB5 bladder cancer cells that express AR and possess intrinsic resistance to gemcitabine. Our results suggest that enzalutamide may have the potential to treat patients with advanced gemcitabine-resistant bladder cancer with increased AR expression.

Antitumor activity of gemcitabine can be potentiated in pancreatic cancer through modulation of TLR4/NF-κB signaling by 6-shogaol.

PubMed

Zhou, Ling; Qi, Lianwen; Jiang, Lifeng; Zhou, Ping; Ma, Jiang; Xu, Xiaojun; Li, Ping

2014-03-01

Advanced pancreatic cancer still has a poor prognosis, even with the approval of several drugs, such as gemcitabine. Therefore, developing effective and safe antitumor agents is urgently needed. 6-Shogaol, a phenol extracted from ginger, has been linked to suppression of proliferation and survival of cancer with different mechanisms. In the present study, we investigated whether 6-shogaol could suppress pancreatic cancer progress and potentiate pancreatic cancer to gemcitabine treatment in vitro and in vivo. We found that 6-shogaol prevented the activation of toll like receptor 4 (TLR4)/NF-κB signaling. The modulation of NF-κB signaling by 6-shogaol was ascertained by electrophoretic mobility shift assay and western blot analysis. The suppression of NF-κB signaling and key cell survival regulators including COX-2, cyclinD1, survivin, cIAP-1, XIAP, Bcl-2, and MMP-9 brought the anti-proliferation effects in pancreatic cancer cells and sensitized them to gemcitabine treatment. Furthermore, in a pancreatic cancer xenograft model, we found a decreased proliferation index (Ki-67) and increased apoptosis by TUNEL staining in 6-shogaol treated tumors. It was also shown that 6-shogaol combined with gemcitabine treatment was more effective than drug alone, consistent with the downregulation of NF-κB activity along with its target genes COX-2, cyclinD1, survivin, cIAP-1, and XIAP. Overall, our results suggest that 6-shogaol can inhibit the growth of human pancreatic tumors and sensitize them to gemcitabine by suppressing of TLR4/NF-κB-mediated inflammatory pathways linked to tumorigenesis.

LCL124, a Cationic Analog of Ceramide, Selectively Induces Pancreatic Cancer Cell Death by Accumulating in Mitochondria

PubMed Central

Beckham, Thomas H.; Lu, Ping; Jones, Elizabeth E.; Marrison, Tucker; Lewis, Clayton S.; Cheng, Joseph C.; Ramshesh, Venkat K.; Beeson, Gyda; Beeson, Craig C.; Drake, Richard R.; Bielawska, Alicja; Bielawski, Jacek; Szulc, Zdzislaw M.; Ogretmen, Besim; Norris, James S.

2013-01-01

Treatment of pancreatic cancer that cannot be surgically resected currently relies on minimally beneficial cytotoxic chemotherapy with gemcitabine. As the fourth leading cause of cancer-related death in the United States with dismal survival statistics, pancreatic cancer demands new and more effective treatment approaches. Resistance to gemcitabine is nearly universal and appears to involve defects in the intrinsic/mitochondrial apoptotic pathway. The bioactive sphingolipid ceramide is a critical mediator of apoptosis initiated by a number of therapeutic modalities. It is noteworthy that insufficient ceramide accumulation has been linked to gemcitabine resistance in multiple cancer types, including pancreatic cancer. Taking advantage of the fact that cancer cells frequently have more negatively charged mitochondria, we investigated a means to circumvent resistance to gemcitabine by targeting delivery of a cationic ceramide (l-t-C6-CCPS [LCL124: ((2S,3S,4E)-2-N-[6′-(1″-pyridinium)-hexanoyl-sphingosine bromide)]) to cancer cell mitochondria. LCL124 was effective in initiating apoptosis by causing mitochondrial depolarization in pancreatic cancer cells but demonstrated significantly less activity against nonmalignant pancreatic ductal epithelial cells. Furthermore, we demonstrate that the mitochondrial membrane potentials of the cancer cells were more negative than nonmalignant cells and that dissipation of this potential abrogated cell killing by LCL124, establishing that the effectiveness of this compound is potential-dependent. LCL124 selectively accumulated in and inhibited the growth of xenografts in vivo, confirming the tumor selectivity and therapeutic potential of cationic ceramides in pancreatic cancer. It is noteworthy that gemcitabine-resistant pancreatic cancer cells became more sensitive to subsequent treatment with LCL124, suggesting that this compound may be a uniquely suited to overcome gemcitabine resistance in pancreatic cancer. PMID:23086228

Inhibition of oncogenic Pim-3 kinase modulates transformed growth and chemosensitizes pancreatic cancer cells to gemcitabine

PubMed Central

Xu, Dapeng; Cobb, Michael G.; Gavilano, Lily; Witherspoon, Sam M.; Williams, Daniel; White, Catherine D.; Taverna, Pietro; Bednarski, Brian K.; Kim, Hong Jin; Baldwin, Albert S.; Baines, Antonio T.

2013-01-01

Pancreatic ductal adenocarcinoma (PDAC) is a lethal cancer with a 5-year survival rate of only 6%. Although the cytosine analog gemcitabine is the drug commonly used to treat PDAC, chemoresistance unfortunately renders the drug ineffective. Thus, strategies that can decrease this resistance will be essential for improving the dismal outcome of patients suffering from this disease. We previously observed that oncogenic Pim-1 kinase was aberrantly expressed in PDAC tissues and cell lines and was responsible for radioresistance. Furthermore, members of the Pim family have been shown to reduce the efficacy of chemotherapeutic drugs in cancer. Therefore, we attempted to evaluate the role of Pim-3 in chemoresistance of PDAC cells. We were able to confirm upregulation of the Pim-3 oncogene in PDAC tissues and cell lines vs. normal samples. Biological consequences of inhibiting Pim-3 expression with shRNA-mediated suppression included decreases in anchorage-dependent growth, invasion through Matrigel and chemoresistance to gemcitabine as measured by caspase-3 activity. Additionally, we were able to demonstrate that Pim-1 and Pim-3 play overlapping but non-identical roles as it relates to gemcitabine sensitivity of pancreatic cancer cells. To further support the role of Pim-3 suppression in sensitizing PDAC cells to gemcitabine, we used the pharmacological Pim kinase inhibitor SGI-1776. Treatment of PDAC cells with SGI-1776 resulted in decreased phosphorylation of the proapoptotic protein Bad and cell cycle changes. When SGI-1776 was combined with gemcitabine, there was a greater decrease in cell viability in the PDAC cells vs. cells treated with either of the drugs separately. These results suggest combining drug therapies that inhibit Pim kinases, such as Pim-3, with chemotherapeutic agents, to aid in decreasing chemoresistance in pancreatic cancer. PMID:23760491

Dasatinib and Gemcitabine Hydrochloride or Gemcitabine Hydrochloride Alone in Treating Patients With Pancreatic Cancer Previously Treated With Surgery

ClinicalTrials.gov

2018-01-05

Acinar Cell Adenocarcinoma of the Pancreas; Duct Cell Adenocarcinoma of the Pancreas; Recurrent Pancreatic Cancer; Stage IA Pancreatic Cancer; Stage IB Pancreatic Cancer; Stage IIA Pancreatic Cancer; Stage IIB Pancreatic Cancer; Stage III Pancreatic Cancer

Gemcitabine and paclitaxel associated pneumonitis in non-small cell lung cancer: report of a phase I/II dose-escalating study.

PubMed

Thomas, A L; Cox, G; Sharma, R A; Steward, W P; Shields, F; Jeyapalan, K; Muller, S; O'Byrne, K J

2000-12-01

The aim of this phase I/II dose escalating study was to establish the maximum tolerated dose (MTD) of gemcitabine and paclitaxel given in combination in non-small cell lung cancer (NSCLC). 12 patients with stage IIIB and IV NSCLC received paclitaxel administered intravenously over 1 h followed by gemcitabine given over 30 min on days 1, 8 and 15 every 28 days. Pneumonitis was the principal side-effect observed with 4 patients affected. Of these, 1 experienced grade 3 toxicity after one cycle of treatment and the others had grade 2 toxicity. All 4 cases responded to prednisolone. No other significant toxicities were observed. Of the 8 evaluable patients, 3 had a partial response and 2 had minor responses. The study was discontinued due to this dose-limiting toxicity. The combination of paclitaxel and gemcitabine shows promising antitumour activity in NSCLC, however, this treatment schedule may predispose to pneumonitis.

Randomised phase 3 open-label trial of first-line treatment with gemcitabine in association with docetaxel or paclitaxel in women with metastatic breast cancer: a comparison of different schedules and treatments

PubMed Central

2013-01-01

Background This open-label study compared docetaxel/gemcitabine vs. paclitaxel/gemcitabine and a weekly (W) vs. 3-weekly (3 W) schedule in metastatic breast cancer (MBC). Methods Patients relapsed after adjuvant/neoadjuvant anthracycline-containing chemotherapy were randomized to: A) gemcitabine 1000 mg/m2 Day 1,8 + docetaxel 75 mg/m2 Day 1 q3W; B) gemcitabine 1250 mg/m2 Day 1,8 + paclitaxel 175 mg/m2 Day 1 q3W; C) gemcitabine 800 mg/m2 Day 1,8,15 + docetaxel 30 mg/m2 Day 1,8,15 q4W; D) gemcitabine 800 mg/m2 Day 1,15 + paclitaxel 80 mg/m2 Day 1,8,15 q4W. Primary endpoint was time-to-progression (TTP). Secondary endpoints were overall survival (OS) and overall response rate (ORR). Results Interim analysis led to accrual interruption (241 patients enrolled of 360 planned). Median TTP (months) was 8.33 (95% CI: 6.19-10.16) with W and 7.51 (95% CI: 5.93-8.33) with 3 W (p=0.319). No differences were observed in median TTP between docetaxel and paclitaxel, with 85.6% and 87.0% of patients progressing, respectively. OS did not differ between regimens/schedules. ORR was comparable between regimens (HR: 0.882; 95% CI: 0.523-1.488; p=0.639), while it was significantly higher in W than in the 3 W (HR: 0.504; 95% CI: 0.299-0.850; p=0.010) schedule. Grade 3/4 toxicities occurred in 69.2% and 71.9% of patients on docetaxel and paclitaxel, and in 65.8% and 75.2% in W and 3 W. Conclusions Both treatment regimens showed similar TTP. W might be associated with a better tumour response compared with 3 W. Trial registration Clinicaltrial.gov ID NCT00236899 PMID:23537313

Differential Processing of let-7a Precursors Influences RRM2 Expression and Chemosensitivity in Pancreatic Cancer: Role of LIN-28 and SET Oncoprotein

PubMed Central

Bhutia, Yangzom Doma; Hung, Sau Wai; Krentz, Madeline; Patel, Dimal; Lovin, Dylan; Manoharan, Radhika; Thomson, J. Michael; Govindarajan, Rajgopal

2013-01-01

Overexpression of ribonucleotide reductase subunit M2 (RRM2), involved in deoxyribonucleotide synthesis, drives the chemoresistance of pancreatic cancer to nucleoside analogs (e.g., gemcitabine). While silencing RRM2 by synthetic means has shown promise in reducing chemoresistance, targeting endogenous molecules, especially microRNAs (miRNAs), to advance chemotherapeutic outcomes has been poorly explored. Based on computational predictions, we hypothesized that the let-7 tumor suppressor miRNAs will inhibit RRM2-mediated gemcitabine chemoresistance in pancreatic cancer. Reduced expression of the majority of let-7 miRNAs with an inverse relationship to RRM2 expression was identified in innately gemcitabine-resistant pancreatic cancer cell lines. Direct binding of let-7 miRNAs to the 3′ UTR of RRM2 transcripts identified post-transcriptional regulation of RRM2 influencing gemcitabine chemosensitivity. Intriguingly, overexpression of human precursor-let-7 miRNAs led to differential RRM2 expression and chemosensitivity responses in a poorly differentiated pancreatic cancer cell line, MIA PaCa-2. Defective processing of let-7a precursors to mature forms, in part, explained the discrepancies observed with let-7a expressional outcomes. Consistently, the ratios of mature to precursor let-7a were progressively reduced in gemcitabine-sensitive L3.6pl and Capan-1 cell lines induced to acquire gemcitabine resistance. Besides known regulators of let-7 biogenesis (e.g., LIN-28), short hairpin RNA library screening identified several novel RNA binding proteins, including the SET oncoprotein, to differentially impact let-7 biogenesis and chemosensitivity in gemcitabine-sensitive versus -resistant pancreatic cancer cells. Further, LIN-28 and SET knockdown in the cells led to profound reductions in cellular proliferation and colony-formation capacities. Finally, defective processing of let-7a precursors with a positive correlation to RRM2 overexpression was identified in patient-derived pancreatic ductal adenocarcinoma (PDAC) tissues. These data demonstrate an intricate post-transcriptional regulation of RRM2 and chemosensitivity by let-7a and that the manipulation of regulatory proteins involved in let-7a transcription/processing may provide a mechanism for improving chemotherapeutic and/or tumor growth control responses in pancreatic cancer. PMID:23335963

Establishment of a pancreatic cancer stem cell model using the SW1990 human pancreatic cancer cell line in nude mice.

PubMed

Pan, Yan; Gao, Song; Hua, Yong-Qiang; Liu, Lu-Ming

2015-01-01

To establish a pancreatic cancer stem cell model using human pancreatic cancer cells in nude mice to provide a platform for pancreatic cancer stem cell research. To establish pancreatic cancer xenografts using human pancreatic cancer cell line SW1990, nude mice were randomly divided into control and gemcitabine groups. When the tumor grew to a volume of 125 mm3, they treated with gemcitabine at a dose of 50 mg/kg by intraperitoneal injection of 0.2 ml in the gemcitabine group, while the mice in control group were treated with the same volume of normal saline. Gemcitabine was given 2 times a week for 3 times. When the model was established, the proliferation of pancreatic cancer stem cells was observed by clone formation assay, and the protein and/or mRNA expression of pancreatic stem cell surface markers including CD24, CD44, CD133, ALDH, transcription factors containing Oct-4, Sox-2, Nanog and Gli, the key nuclear transcription factor in Sonic Hedgehog signaling pathway was detected by Western blot and/or RT-PCR to verify the reliability of this model. This model is feasible and safe. During the establishment, no mice died and the weight of nude mice maintained above 16.5 g. The clone forming ability in gemcitabine group was stronger than that of the control group (p<0.01). In gemcitabine group, the protein expression of pancreatic cancer stem cell surface markers including CD44, and ALDH was up-regulated, the protein and mRNA expression of nuclear transcription factor including Oct-4, Sox-2 and Nanog was also significantly increased (P<0.01). In addition, the protein expression of key nuclear transcription factor in Sonic Hedgehog signaling pathway, Gli-1, was significantly enhanced (p<0.01). The pancreatic cancer stem cell model was successfully established using human pancreatic cancer cell line SW1990 in nude mice. Gemcitabine could enrich pancreatic cancer stem cells, simultaneously accompanied by the activation of Sonic Hedgehog signaling pathway.

Delayed response to maintenance therapy after first-line chemotherapy in metastatic intrahepatic cholangiocarcinoma: a case report.

PubMed

Marciano, Roberta; Servetto, Alberto; Bianco, Cataldo; Bianco, Roberto

2017-09-26

Intrahepatic cholangiocarcinoma is an aggressive tumor originating in the epithelium of the bile duct, often associated with distant dissemination. The prognosis is poor and treatment is challenging due to low response rate to standard chemotherapy and lack of targeted therapies. Here we report the case of a 74-year-old white woman affected by intrahepatic cholangiocarcinoma with metastatic involvement of spleen, lung, peritoneum, and intra-abdominal lymph nodes. As first-line chemotherapy, she was given cisplatin-gemcitabine chemotherapy. The treatment was well tolerated with the exception of grade 1 constipation and a single episode of grade 4 thrombocytopenia occurring after the fourth course. After the first three courses of chemotherapy a computed tomography scan evaluation demonstrated no change; her CA19-9 levels were slightly decreased. However, after the sixth course of chemotherapy a computed tomography scan revealed a dimensional enlargement of the lung metastases; her CA19-9 levels increased. She was then treated with gemcitabine alone. After 2 months of gemcitabine monotherapy a significant regression of lung and spleen metastases, as well a CA19-9 level reduction, occurred. Eight months after the start of gemcitabine monotherapy no signs of progression were reported. Treatment of metastatic intrahepatic cholangiocarcinoma with gemcitabine as maintenance therapy after first-line chemotherapy could be continued until clear evidence of disease progression since delayed responses are possible.

Analysis of the efficacy and safety of a combined gemcitabine, oxaliplatin and pegaspargase regimen for NK/T-cell lymphoma

PubMed Central

Xia, Zhong-jun; Huang, Hui-qiang; Jiang, Wen-qi; Lu, Yue

2016-01-01

Extranodal natural killer/T-cell lymphoma (ENKTL) is an aggressive neoplasm with a poor outcome. Novel L-asparaginase-based treatment regimens, such as GELOX (gemcitabine, oxaliplatin, and L-asparaginase) and P-gemox (gemcitabine, oxaliplatin, and pegaspargase), have shown promising results against stage IE/IIE ENKTL. To define the general applicability of P-gemox, in a retrospective analysis we examined the efficacy and safety of P-gemox in a cohort of 117 patients with newly diagnosed or relapsed/refractory ENKTL. Treatment included 2 to 8 cycles of P-gemox: intravenous gemcitabine (1250 mg/m2) and oxaliplatin (85 mg/m2) and intramuscular pegaspargase (2500 IU/m2) on day 1 and repeated every 2 weeks, or intravenous gemcitabine (1000 mg/m2) on days 1 and 8 and intravenous oxaliplatin (130 mg/m2) and intramuscular pegaspargase (2500 IU/m2) on day 1 and repeated every 3 weeks. Upon completion of treatment, the overall response rate was 88.8%, and responses were similar for newly diagnosed and relapsed/refractory patients. After a median follow-up of 17 months, the 3-year overall and progression-free survival rates were 72.7% and 57.8%, respectively. Multivariate analysis showed that CR after treatment was the most significant factor affecting survival. P-gemox thus appears to be an effective and well-tolerated treatment for patients with ENKTL. PMID:27072578

Posttranscriptional Upregulation of IDH1 by HuR Establishes a Powerful Survival Phenotype in Pancreatic Cancer Cells

PubMed Central

Zarei, Mahsa; Lal, Shruti; Parker, Seth J.; Nevler, Avinoam; Vaziri-Gohar, Ali; Dukleska, Katerina; Mambelli-Lisboa, Nicole C.; Moffat, Cynthia; Blanco, Fernando F.; Chand, Saswati N.; Jimbo, Masaya; Cozzitorto, Joseph A.; Jiang, Wei; Yeo, Charles J.; Londin, Eric R.; Seifert, Erin L.; Metallo, Christian M.; Brody, Jonathan R.; Winter, Jordan M.

2018-01-01

Cancer aggressiveness may result from the selective pressure of a harsh nutrient-deprived microenvironment. Here we illustrate how such conditions promote chemotherapy resistance in pancreatic ductal adenocarcinoma (PDAC). Glucose or glutamine withdrawal resulted in a 5- to 10-fold protective effect with chemotherapy treatment. PDAC xenografts were less sensitive to gemcitabine in hypoglycemic mice compared with hyperglycemic mice. Consistent with this observation, patients receiving adjuvant gemcitabine (n = 107) with elevated serum glucose levels (HgbA1C > 6.5%) exhibited improved survival. We identified enhanced antioxidant defense as a driver of chemoresistance in this setting. ROS levels were doubled in vitro by either nutrient withdrawal or gemcitabine treatment, but depriving PDAC cells of nutrients before gemcitabine treatment attenuated this effect. Mechanistic investigations based on RNAi or CRISPR approaches implicated the RNA binding protein HuR in preserving survival under nutrient withdrawal, with or without gemcitabine. Notably, RNA deep sequencing and functional analyses in HuR-deficient PDAC cell lines identified isocitrate dehydrogenase 1 (IDH1) as the sole antioxidant enzyme under HuR regulation. HuR-deficient PDAC cells lacked the ability to engraft successfully in immunocompromised mice, but IDH1 overexpression in these cells was sufficient to fully restore chemoresistance under low nutrient conditions. Overall, our findings highlight the HuR–IDH1 regulatory axis as a critical, actionable therapeutic target in pancreatic cancer. PMID:28652247

Low MUC4 expression is associated with survival benefit in patients with resectable pancreatic cancer receiving adjuvant gemcitabine.

PubMed

Urey, Carlos; Andersson, Bodil; Ansari, Daniel; Sasor, Agata; Said-Hilmersson, Katarzyna; Nilsson, Johan; Andersson, Roland

2017-05-01

Previous in vitro studies have shown that mucin 4 (MUC4) confers resistance toward gemcitabine in pancreatic cancer cells. To date, there are few clinical studies corroborating these findings. The aim of this study was to evaluate the predictive impact of MUC4 expression on survival in patients with resectable pancreatic cancer receiving adjuvant gemcitabine. MUC4 expression was investigated by immunohistochemistry in 78 tissue sections from patients with pancreatic ductal adenocarcinoma undergoing Whipple resection. The H-score was used to evaluate MUC4 expression. The Kaplan-Meier method and Cox proportional hazards regression analysis were used to assess the predictive role of MUC4 expression. The MUC4 protein was expressed in 93.6% (73/78) of pancreatic cancer tissue specimens. None of the normal control pancreatic tissues had any MUC4 expression. Low MUC4 expression (H-score ≤100) was detectable in 42 (53.8%) of tumors and high MUC4 expression (H-score >100) was detectable in 36 (46.2%) of tumors. Low expression of MUC4 was associated with favorable survival (p = .027), whereas high MUC4 expression did not correlate with survival (p = .87) in patients receiving adjuvant gemcitabine treatment. This is the first study indicating a predictive role of MUC4 expression for gemcitabine treatment in the clinical setting.

Enhancement of Gemcitabine sensitivity in pancreatic adenocarcinoma by novel exosome-mediated delivery of the Survivin-T34A mutant

PubMed Central

Aspe, Jonathan R.; Diaz Osterman, Carlos J.; Jutzy, Jessica M.S.; Deshields, Simone; Whang, Sonia; Wall, Nathan R.

2014-01-01

Background Current therapeutic options for advanced pancreatic cancer have been largely disappointing with modest results at best, and though adjuvant therapy remains controversial, most remain in agreement that Gemcitabine should stand as part of any combination study. The inhibitor of apoptosis (IAP) protein Survivin is a key factor in maintaining apoptosis resistance, and its dominant-negative mutant (Survivin-T34A) has been shown to block Survivin, inducing caspase activation and apoptosis. Methods In this study, exosomes, collected from a melanoma cell line built to harbor a tetracycline-regulated Survivin-T34A, were plated on the pancreatic adenocarcinoma (MIA PaCa-2) cell line. Evaluation of the presence of Survivin-T34A in these exosomes followed by their ability to induce Gemcitabine-potentiative cell killing was the objective of this work. Results Here we show that exosomes collected in the absence of tetracycline (tet-off) from the engineered melanoma cell do contain Survivin-T34A and when used alone or in combination with Gemcitabine, induced a significant increase in apoptotic cell death when compared to Gemcitabine alone on a variety of pancreatic cancer cell lines. Conclusion This exosomes/Survivin-T34A study shows that a new delivery method for anticancer proteins within the cancer microenvironment may prove useful in targeting cancers of the pancreas. PMID:24624263

Microfiberoptic fluorescence photobleaching reveals size-dependent macromolecule diffusion in extracellular space deep in brain.

PubMed

Zador, Zsolt; Magzoub, Mazin; Jin, Songwan; Manley, Geoffrey T; Papadopoulos, Marios C; Verkman, A S

2008-03-01

Diffusion in brain extracellular space (ECS) is important for nonsynaptic intercellular communication, extracellular ionic buffering, and delivery of drugs and metabolites. We measured macromolecular diffusion in normally light-inaccessible regions of mouse brain by microfiberoptic epifluorescence photobleaching, in which a fiberoptic with a micron-size tip is introduced deep in brain tissue. In brain cortex, the diffusion of a noninteracting molecule [fluorescein isothiocyanate (FITC)-dextran, 70 kDa] was slowed 4.5 +/- 0.5-fold compared with its diffusion in water (D(o)/D), and was depth-independent down to 800 microm from the brain surface. Diffusion was significantly accelerated (D(o)/D of 2.9+/-0.3) in mice lacking the glial water channel aquaporin-4. FITC-dextran diffusion varied greatly in different regions of brain, with D(o)/D of 3.5 +/- 0.3 in hippocampus and 7.4 +/- 0.3 in thalamus. Remarkably, D(o)/D in deep brain was strongly dependent on solute size, whereas diffusion in cortex changed little with solute size. Mathematical modeling of ECS diffusion required nonuniform ECS dimensions in deep brain, which we call "heterometricity," to account for the size-dependent diffusion. Our results provide the first data on molecular diffusion in ECS deep in brain in vivo and demonstrate previously unrecognized hindrance and heterometricity for diffusion of large macromolecules in deep brain.

Stability and Noise in the Cyanobacterial Circadian Clock

NASA Astrophysics Data System (ADS)

Mihalcescu, Irina

2008-03-01

Accuracy in cellular function has to be achieved despite random fluctuations (noise) in the concentrations of different molecular constituents inside and outside the cell. Single cell in vivo monitoring reveals that individual cells generate autonomous circadian rhythms in protein abundance. In multi-cellular organisms, the individual cell rhythms appear to be noisy with drifting phases and frequencies. However, the whole organism is significantly more accurate, the temporal precision being achieved most probably via intercellular coupling of the individual noisy oscillators. In cyanobacteria, we have shown that single cell oscillators are impressively stable and a first estimation rules out strong intercellular coupling. Interestingly, these prokaryotes also have the simplest molecular mechanism at the heart of their circadian clock. In the absence of transcriptional activity in vivo, as well alone in vitro, the three clock proteins KaiA, KaiB and KaiC generate a self-sustained circadian oscillation of autophosphorylation and dephosphorylation. Recent chemical kinetics models provide a possible understanding of the three-protein oscillator, but the measured in vivo stability remains yet unexplained. Is the clock stability a built-in property for each bacterium or does a weak intercellular coupling, make them appear like that? To address this question we first theoretically designed our experiment to be able to distinguish coupling, even weak, from phase diffusion. As the precision of our evaluation increases with the length of the experiments, we continuously monitor, for a couple of weeks, mixtures of cell populations with different initial phases. The inherent experimental noise contribution, initially dominant, is reduced by enhanced statistics. In addition, in situ entrainment experiments confirm our ability to detect a coupling of the circadian oscillator to an external force and to describe explicitly the dynamic change of the mean phase. We report a value of the coupling constant that is small compared to the diffusion constant. These results therefore confirm that the cyanobacterial clock stability is a built-in property: the cyanobacterian clock mechanism is not only the simplest but also the most robust.

Treatment Extends Survival for Women with Cervical Cancer

Cancer.gov

Patients with locally advanced cervical cancer who received gemcitabine (Gemzar®) both as part of initial treatment and as part of therapy following primary treatment had improved survival compared with patients whose treatment did not include gemcitabine, according to findings presented at the 2009 ASCO meeting in Orlando.

Role of ABCB5 P-Glycoprotein in Breast Cancer Multidrug Resistance

DTIC Science & Technology

2005-09-01

Hydroxyurea Doxorubicin Porfiromycin Mechlorethamine Fluorodopan Mitomycin Cytarabine (araC) Dianhydrogalactitol Gemcitabine Thiotepa N-N-Dibenzyl-daunomycin...0.0196 Mitomycin 0.4173 0.0318 Cytarabine (araC) 0.4163 0.0288 Dianhydrogalactitol 0.4105 0.0354 Gemcitabine 0.4088 0.0302 Thiotepa 0.4015 0.0232

Development and characterization of polymeric nanoparticulate delivery system for hydrophillic drug: Gemcitabine

NASA Astrophysics Data System (ADS)

Khurana, Jatin

Gemcitabine is a nucleoside analogue, used in various carcinomas such as non small cell lung cancer, pancreatic cancer, ovarian cancer and breast cancer. The major setbacks to the conventional therapy with gemcitabine include its short half-life and highly hydrophilic nature. The objectives of this investigation were to develop and evaluate the physiochemical properties, drug loading and entrapment efficiency, in vitro release, cytotoxicity, and cellular uptake of polymeric nano-particulate formulations containing gemcitabine hydrochloride. The study also entailed development and validation of a high performance liquid chromatography (HPLC) method for the analysis of gemcitabine hydrochloride. A reverse phase HPLC method using a C18 Luna column was developed and validated. Alginate and Poly lactide co glycolide/Poly-epsilon-caprolactone (PLGA:PCL 80:20) nanoparticles were prepared by multiple emulsion-solvent evaporation methodology. An aqueous solution of low viscosity alginate containing gemcitabine was emulsified into 10% solution of dioctyl-sulfosuccinate in dichloro methane (DCM) by sonication. The primary emulsion was then emulsified in 0.5% (w/v) aqueous solution of polyvinyl alcohol (PVA). Calcium chloride solution (60% w/v) was used to cause cross linking of the polymer. For PLGA:PCL system, the polymer mix was dissolved in dichloromethane (DCM) and an aqueous gemcitabine (with and without sodium chloride) was emulsified under ultrasonic conditions (12-watts; 1-min). This primary emulsion was further emulsified in 2% (w/v) PVA under ultrasonic conditions (24-watts; 3-min) to prepare a multiple-emulsion (w/o/w). In both cases DCM, the organic solvent was evaporated (20- hours, magnetic-stirrer) prior to ultracentrifugation (10000-rpm for PLGA:PCL; 25000-rpm for alginate). The pellet obtained was washed thrice with de-ionized water to remove PVA and any free drug and re-centrifuged. The particles were re-suspended in de-ionized water and then lyophilized to obtain the dried powdered delivery formulation. Particle size and surface charge of the nano-particles were measured using zeta-sizer. The surface morphology and microstructure were evaluated by scanning electron microscopy The drug loading and entrapment efficiencies were evaluated by a HPLC method (Luna C18 column (4.6 X 250 mm), 95/5 (v/v) 0.04M ammonium acetate/acetonitrile mobile phase (pH 5.5), 1.0 ml/min flow rate and 268 nm UV detection). Differential scanning calorimetry (DSC) was used to determine the physical state of gemcitabine in the nanoparticles. The cytotoxicity in pancreatic cancer cells (BxPC-3) was evaluated by MTT assay. The cellular uptake of gemcitabine solution and gemcitabine loaded alginate nano-particle suspension in BxPC-3 cells was determined for 15, 30 and 60 minutes. The particle-size and surface-charge was 564.7+/-56.5nm and -25.65+/-1.94mV for PLGA:PCL and 210.6+/-6.90nm and -33.21+/-1.63mV for alginate. Both the nano-particles were distinctly spherical and non-porous. The drug load was 5.14% for PLGA:PCL and 6.87% for alginate-particles, and the practical entrapment efficiency was found to be 54.1 % and 22.4% respectively. However, in case of PLGA:PCL particles, a two-fold increase in the entrapment efficiency was observed with the addition of sodium-chloride. The absence of endothermic melting peak of the drug in the DSC thermogram was an indication of the non-crystalline state of gemcitabine in the nanoparticles. In addition, there was no cytotoxicity associated with nanoparticle concentrations at-or-below 5 mg/mL. The uptake of nano-particles was around 4 times higher than the solution with treatment for 15 minutes and increased to almost 7 times following treatment for 60 minutes. Gemcitabine hydrochloride could be successfully formulated into a sustained release nano-particulate formulation using calcium cross-linked alginate and dioctyl sulfo succinate system. The nano-particulate delivery system exhibited better cytotoxic activity and also significantly enhanced the accumulation of the drug in BxPC-3 cell monolayers.

Different domains are critical for oligomerization compatibility of different connexins

PubMed Central

MARTÍNEZ, Agustín D.; MARIPILLÁN, Jaime; ACUÑA, Rodrigo; MINOGUE, Peter J.; BERTHOUD, Viviana M.; BEYER, Eric C.

2011-01-01

Oligomerization of connexins is a critical step in gap junction channel formation. Some members of the connexin family can oligomerize with other members and form functional heteromeric hemichannels [e.g. Cx43 (connexin 43) and Cx45], but others are incompatible (e.g. Cx43 and Cx26). To find connexin domains important for oligomerization, we constructed chimaeras between Cx43 and Cx26 and studied their ability to oligomerize with wild-type Cx43, Cx45 or Cx26. HeLa cells co-expressing Cx43, Cx45 or Cx26 and individual chimaeric constructs were analysed for interactions between the chimaeras and the wild-type connexins using cell biological (subcellular localization by immunofluorescence), functional (intercellular diffusion of microinjected Lucifer yellow) and biochemical (sedimentation velocity through sucrose gradients) assays. All of the chimaeras containing the third transmembrane domain of Cx43 interacted with wild-type Cx43 on the basis of co-localization, dominant-negative inhibition of intercellular communication, and altered sedimentation velocity. The same chimaeras also interacted with co-expressed Cx45. In contrast, immunofluorescence and intracellular diffusion of tracer suggested that other domains influenced oligomerization compatibility when chimaeras were co-expressed with Cx26. Taken together, these results suggest that amino acids in the third transmembrane domain are critical for oligomerization with Cx43 and Cx45. However, motifs in different domains may determine oligomerization compatibility in members of different connexin subfamilies. PMID:21348854

Coordination of Leaf Photosynthesis, Transpiration, and Structural Traits in Rice and Wild Relatives (Genus Oryza)1[W][OA

PubMed Central

Giuliani, Rita; Koteyeva, Nuria; Voznesenskaya, Elena; Evans, Marc A.; Cousins, Asaph B.; Edwards, Gerald E.

2013-01-01

The genus Oryza, which includes rice (Oryza sativa and Oryza glaberrima) and wild relatives, is a useful genus to study leaf properties in order to identify structural features that control CO2 access to chloroplasts, photosynthesis, water use efficiency, and drought tolerance. Traits, 26 structural and 17 functional, associated with photosynthesis and transpiration were quantified on 24 accessions (representatives of 17 species and eight genomes). Hypotheses of associations within, and between, structure, photosynthesis, and transpiration were tested. Two main clusters of positively interrelated leaf traits were identified: in the first cluster were structural features, leaf thickness (Thickleaf), mesophyll (M) cell surface area exposed to intercellular air space per unit of leaf surface area (Smes), and M cell size; a second group included functional traits, net photosynthetic rate, transpiration rate, M conductance to CO2 diffusion (gm), stomatal conductance to gas diffusion (gs), and the gm/gs ratio. While net photosynthetic rate was positively correlated with gm, neither was significantly linked with any individual structural traits. The results suggest that changes in gm depend on covariations of multiple leaf (Smes) and M cell (including cell wall thickness) structural traits. There was an inverse relationship between Thickleaf and transpiration rate and a significant positive association between Thickleaf and leaf transpiration efficiency. Interestingly, high gm together with high gm/gs and a low Smes/gm ratio (M resistance to CO2 diffusion per unit of cell surface area exposed to intercellular air space) appear to be ideal for supporting leaf photosynthesis while preserving water; in addition, thick M cell walls may be beneficial for plant drought tolerance. PMID:23669746

Collective cell migration of thyroid carcinoma cells: a beneficial ability to override unfavourable substrates.

PubMed

Lobastova, Liudmila; Kraus, Dominik; Glassmann, Alexander; Khan, Dilaware; Steinhäuser, Christian; Wolff, Christina; Veit, Nadine; Winter, Jochen; Probstmeier, Rainer

2017-02-01

Tumor cell invasion and metastasis are life threatening events. Invasive tumor cells tend to migrate as collective sheets. In the present in vitro study we aimed to (i) assess whether collective tumor cells gain benefits in their migratory potential compared to single cells and (ii) to identify its putative underlying molecular mechanisms. The migratory potential of single and collective carcinoma cells was assessed using video time lapse microscopy and cell migration assays in the absence and presence of seven potential gap junction inhibitors or the Rac1 inhibitor Z62954982. The perturbation of gap junctions was assessed using a dye diffusion assay. In addition, LDH-based cytotoxicity and RT-PCR-based expression analyses were performed. Whereas single breast, cervix and thyroid carcinoma cells were virtually immobile on unfavourable plastic surfaces, we found that they gained pronounced migratory capacities as collectives under comparable conditions. Thyroid carcinoma cells, that were studied in more detail, were found to express specific subsets of connexins and to form active gap junctions as revealed by dye diffusion analysis. Although all potential gap junction blockers suppressed intercellular dye diffusion in at least one of the cell lines tested, only two of them were found to inhibit collective cell migration and none of them to inhibit single cell migration. In the presence of the Rac1 inhibitor Z62954982 collective migration, but not single cell migration, was found to be reduced up to 20 %. Our data indicate that collective migration enables tumor cells to cross otherwise unfavourable substrate areas. This capacity seems to be independent of intercellular communication via gap junctions, whereas Rac1-dependent intracellular signalling seems to be essential.

Regulation of respiration and the oxygen diffusion barrier in soybean protect symbiotic nitrogen fixation from chilling-induced inhibition and shoots from premature senescence.

PubMed

van Heerden, Philippus D R; Kiddle, Guy; Pellny, Till K; Mokwala, Phatlane W; Jordaan, Anine; Strauss, Abram J; de Beer, Misha; Schlüter, Urte; Kunert, Karl J; Foyer, Christine H

2008-09-01

Symbiotic nitrogen fixation is sensitive to dark chilling (7 degrees C-15 degrees C)-induced inhibition in soybean (Glycine max). To characterize the mechanisms that cause the stress-induced loss of nodule function, we examined nodule structure, carbon-nitrogen interactions, and respiration in two soybean genotypes that differ in chilling sensitivity: PAN809 (PAN), which is chilling sensitive, and Highveld Top (HT), which is more chilling resistant. Nodule numbers were unaffected by dark chilling, as was the abundance of the nitrogenase and leghemoglobin proteins. However, dark chilling decreased nodule respiration rates, nitrogenase activities, and NifH and NifK mRNAs and increased nodule starch, sucrose, and glucose in both genotypes. Ureide and fructose contents decreased only in PAN nodules. While the chilling-induced decreases in nodule respiration persisted in PAN even after return to optimal temperatures, respiration started to recover in HT by the end of the chilling period. The area of the intercellular spaces in the nodule cortex and infected zone was greatly decreased in HT after three nights of chilling, an acclimatory response that was absent from PAN. These data show that HT nodules are able to regulate both respiration and the area of the intercellular spaces during chilling and in this way control the oxygen diffusion barrier, which is a key component of the nodule stress response. We conclude that chilling-induced loss of symbiotic nitrogen fixation in PAN is caused by the inhibition of respiration coupled to the failure to regulate the oxygen diffusion barrier effectively. The resultant limitations on nitrogen availability contribute to the greater chilling-induced inhibition of photosynthesis in PAN than in HT.

Regulation of Respiration and the Oxygen Diffusion Barrier in Soybean Protect Symbiotic Nitrogen Fixation from Chilling-Induced Inhibition and Shoots from Premature Senescence1[W][OA

PubMed Central

van Heerden, Philippus D.R.; Kiddle, Guy; Pellny, Till K.; Mokwala, Phatlane W.; Jordaan, Anine; Strauss, Abram J.; de Beer, Misha; Schlüter, Urte; Kunert, Karl J.; Foyer, Christine H.

2008-01-01

Symbiotic nitrogen fixation is sensitive to dark chilling (7°C–15°C)-induced inhibition in soybean (Glycine max). To characterize the mechanisms that cause the stress-induced loss of nodule function, we examined nodule structure, carbon-nitrogen interactions, and respiration in two soybean genotypes that differ in chilling sensitivity: PAN809 (PAN), which is chilling sensitive, and Highveld Top (HT), which is more chilling resistant. Nodule numbers were unaffected by dark chilling, as was the abundance of the nitrogenase and leghemoglobin proteins. However, dark chilling decreased nodule respiration rates, nitrogenase activities, and NifH and NifK mRNAs and increased nodule starch, sucrose, and glucose in both genotypes. Ureide and fructose contents decreased only in PAN nodules. While the chilling-induced decreases in nodule respiration persisted in PAN even after return to optimal temperatures, respiration started to recover in HT by the end of the chilling period. The area of the intercellular spaces in the nodule cortex and infected zone was greatly decreased in HT after three nights of chilling, an acclimatory response that was absent from PAN. These data show that HT nodules are able to regulate both respiration and the area of the intercellular spaces during chilling and in this way control the oxygen diffusion barrier, which is a key component of the nodule stress response. We conclude that chilling-induced loss of symbiotic nitrogen fixation in PAN is caused by the inhibition of respiration coupled to the failure to regulate the oxygen diffusion barrier effectively. The resultant limitations on nitrogen availability contribute to the greater chilling-induced inhibition of photosynthesis in PAN than in HT. PMID:18667725

Coordination of Leaf Photosynthesis, Transpiration, and Structural Traits in Rice and Wild Relatives (Genus Oryza).

PubMed

Giuliani, Rita; Koteyeva, Nuria; Voznesenskaya, Elena; Evans, Marc A; Cousins, Asaph B; Edwards, Gerald E

2013-07-01

The genus Oryza, which includes rice (Oryza sativa and Oryza glaberrima) and wild relatives, is a useful genus to study leaf properties in order to identify structural features that control CO(2) access to chloroplasts, photosynthesis, water use efficiency, and drought tolerance. Traits, 26 structural and 17 functional, associated with photosynthesis and transpiration were quantified on 24 accessions (representatives of 17 species and eight genomes). Hypotheses of associations within, and between, structure, photosynthesis, and transpiration were tested. Two main clusters of positively interrelated leaf traits were identified: in the first cluster were structural features, leaf thickness (Thick(leaf)), mesophyll (M) cell surface area exposed to intercellular air space per unit of leaf surface area (S(mes)), and M cell size; a second group included functional traits, net photosynthetic rate, transpiration rate, M conductance to CO(2) diffusion (g(m)), stomatal conductance to gas diffusion (g(s)), and the g(m)/g(s) ratio.While net photosynthetic rate was positively correlated with gm, neither was significantly linked with any individual structural traits. The results suggest that changes in gm depend on covariations of multiple leaf (S(mes)) and M cell (including cell wall thickness) structural traits. There was an inverse relationship between Thick(leaf) and transpiration rate and a significant positive association between Thick(leaf) and leaf transpiration efficiency. Interestingly, high g(m) together with high g(m)/g(s) and a low S(mes)/g(m) ratio (M resistance to CO(2) diffusion per unit of cell surface area exposed to intercellular air space) appear to be ideal for supporting leaf photosynthesis while preserving water; in addition, thick M cell walls may be beneficial for plant drought tolerance.

Fisetin Reduces Cell Viability Through Up-Regulation of Phosphorylation of ERK1/2 in Cholangiocarcinoma Cells.

PubMed

Kim, Nayoung; Lee, Sang Hyub; Son, Jun Hyuk; Lee, Jae Min; Kang, Min-Jung; Kim, Bo Hye; Lee, Jung-Su; Ryu, Ji Kon; Kim, Yong-Tae

2016-11-01

Cholangiocarcinoma (CCA) is a malignancy with poor prognosis and limited therapeutic options. Effective prevention and treatment of CCA require developing novel anticancer agents and improved therapeutic regimens. As natural products are concidered a rich source of potential anticancer agents, we investigated the anticancer effect of fisetin in combination with gemcitabine. Cytotoxic effect of fisetin and gemcitabine on a human CCA cell line SNU-308 was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and apoptosis assay using propidium iodine and annexin V. Molecular mechanisms of fisetin action in CCA were investigated by western blotting. Fisetin was found to inhibit survival of CCA cells, through strongly phosphorylating ERK. It also induced cellular apoptosis additively in combination with gemcitabine. Expression of cellular proliferative markers, such as phospho-p65 and myelocytomatosis (MYC), were reduced by fisetin. These results suggest fisetin in combination with gemcitabine as a candidate for use in improved anticancer regimens. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Phase II study of neoadjuvant gemcitabine, pegylated liposomal doxorubicin, and docetaxel in locally advanced breast cancer.

PubMed

Artioli, Grazia; Grazia, Artioli; Mocellin, Simone; Simone, Mocellin; Borgato, Lucia; Lucia, Borgato; Cappetta, Alessandro; Alessandro, Cappetta; Bozza, Fernando; Fernando, Bozza; Zavagno, Giorgio; Giorgio, Zavagno; Zovato, Stefania; Stefania, Zovato; Marchet, Alberto; Alberto, Marchet; Pastorelli, Davide; Davide, Pastorelli

2010-09-01

This was a phase II study to assess the activity of a novel neoadjuvant regimen in locally-advanced breast cancer. Fifty patients with histological confirmation of locally advanced breast cancer received treatment with gemcitabine 1000 mg/m(2) (day 1) followed by gemcitabine 800 mg/m(2) plus docetaxel 75 mg/m(2) plus pegylated liposomal doxorubicin (PLD) 30 mg/m(2) (day 8) every 3 weeks for at least 4 cycles, plus a final 2 additional cycles. Tumour size was T1 (n=2), T2 (n=32), T3 (n=14), T4 (n=2). All 50 patients underwent surgery. Clinical complete, partial and no response were observed in 13 (26%), 24 (48%) and 11 (22%) patients, respectively (overall response rate: 74%). The number of chemotherapy cycles was found to be an independent predictor of a pathologic complete response. The combination of gemcitabine-docetaxel-PLD can yield high tumour response rates in patients with locally-advanced breast cancer who undergo a full treatment of 6 cycles.

Development of Long-Circulating pH-Sensitive Liposomes to Circumvent Gemcitabine Resistance in Pancreatic Cancer Cells.

PubMed

Xu, Hongtao; Paxton, James W; Wu, Zimei

2016-07-01

To develop pH-sensitive liposomes (PSL) containing a high content of gemcitabine; and to investigate whether drug loading (DL) would alter the in vitro and pharmacokinetic properties. PSL with a high DL were obtained using a modified small-volume incubation method. The DL effects on drug release rate and in vitro cytotoxicity of PSL were evaluated using MIA PaCa-2 pancreatic cancer cells and their pharmacokinetics investigated in rats. The highest DL of 4.5 ± 0.1% was achieved for gemcitabine in PSL with 145 ± 5 nm diameter. DL did not alter the in vitro release rate from PSL. The IC50 (48 h) of PSL (DL 0.5 and 4.5%) and non pH-sensitive liposomes (NPSL, DL 4.2%) were 1.1 ± 0.1, 0.7 ± 0.1 and 37.0 ± 7.5 μM, respectively. The PSL resulted in a 4.2-fold increase in its elimination half-life (6.2 h) compared to gemcitabine solution (1.4 h) in rats. No significant difference in pharmacokinetic parameters was observed between the two PSL (DL 0.5 and 4.5%). The PSL offered advantages over NPSL in restoring the sensitivity of pancreatic cancer cells to gemcitabine without requiring a high DL. DL in the PSL did not alter release rate, cytotoxicity or their long-circulating properties. Graphical Abstract ᅟ.

Apatinib concurrent gemcitabine for controlling malignant ascites in advanced pancreatic cancer patient: A case report.

PubMed

Liang, Lijun; Wang, Lei; Zhu, Panrong; Xia, Youyou; Qiao, Yun; Hui, Kaiyuan; Hu, Chenxi; Ren, Yan; Jiang, Xiaodong

2017-11-01

Malignant ascites (MA) is one of the poor prognostic factors for advanced pancreatic cancer and can bring about serious symptoms. The improvement of quality of life for patients is priority. However, there is no standard method for the treatment for pancreatic cancer-mediated MA. Apatinib is a novel and highly selective tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor-2. There are no reports of concurrent apatinib with gemcitabine in patients with pancreatic cancer-mediated MA. Herein, we presented a 64-year-old man patient who visited hospital due to abdominal pain for 1 month. He was initially diagnosed with pancreatic cancer and his first symptom was MA. After failing in tube drainage and gemcitabine therapy, the patient received gemcitabine combined apatinib orally and after administrated 1 month, the MA was evaluated as nearly clear response according to the RECIST 1.1 standard, and without further need of paracentesis. The CEA and CA199 reached the lowest level after administrating for 2.5 months during the treatment process. 10.5 months following apatinib administration, the patient achieved a progression-free survival for more than 11 months. Hypertension (grade IV), hand-foot syndrome (grade I) and proteinuria (grade II) were observed. It indicated that apatinib concurrent gemcitabine may be a superior choice for pancreatic cancer-mediated MA. Further clinical trials required to confirm its efficacy and safety. Copyright © 2017 The Authors. Published by Wolters Kluwer Health, Inc. All rights reserved.

Apatinib concurrent gemcitabine for controlling malignant ascites in advanced pancreatic cancer patient

PubMed Central

Liang, Lijun; Wang, Lei; Zhu, Panrong; Xia, Youyou; Qiao, Yun; Hui, Kaiyuan; Hu, Chenxi; Ren, Yan; Jiang, Xiaodong

2017-01-01

Abstract Rationale: Malignant ascites (MA) is one of the poor prognostic factors for advanced pancreatic cancer and can bring about serious symptoms. The improvement of quality of life for patients is priority. However, there is no standard method for the treatment for pancreatic cancer-mediated MA. Apatinib is a novel and highly selective tyrosine kinase inhibitor targeting vascular endothelial growth factor receptor-2. There are no reports of concurrent apatinib with gemcitabine in patients with pancreatic cancer-mediated MA. Patient concerns: Herein, we presented a 64-year-old man patient who visited hospital due to abdominal pain for 1 month. Diagnoses: He was initially diagnosed with pancreatic cancer and his first symptom was MA. Interventions: After failing in tube drainage and gemcitabine therapy, the patient received gemcitabine combined apatinib orally and after administrated 1 month, the MA was evaluated as nearly clear response according to the RECIST 1.1 standard, and without further need of paracentesis. The CEA and CA199 reached the lowest level after administrating for 2.5 months during the treatment process. Outcomes: 10.5 months following apatinib administration, the patient achieved a progression-free survival for more than 11 months. Hypertension (grade IV), hand-foot syndrome (grade I) and proteinuria (grade II) were observed. Lessons: It indicated that apatinib concurrent gemcitabine may be a superior choice for pancreatic cancer-mediated MA. Further clinical trials required to confirm its efficacy and safety. PMID:29381963

EGFR-targeted gelatin nanoparticles for systemic administration of gemcitabine in an orthotopic pancreatic cancer model.

PubMed

Singh, Amit; Xu, Jing; Mattheolabakis, George; Amiji, Mansoor

2016-04-01

In this study, we have formulated redox-responsive epidermal growth factor receptor (EGFR)-targeted type B gelatin nanoparticles as a targeted vector for systemic delivery of gemcitabine therapy in pancreatic cancer. The gelatin nanoparticles were formed by ethanol-induced desolvation process to encapsulate the bound drug. The surface of the nanoparticles was decorated either with poly(ethylene glycol) (PEG) chains to impart enhanced circulation time or with EGFR targeting peptide to confer target specificity. Our in vitro studies in Panc-1 human pancreatic ductal adenocarcinoma cells confirm that gemcitabine encapsulated in EGFR-targeted gelatin nanoparticles, released through disulfide bond cleavage, had a significantly improved cytotoxic profile. Further, the in vivo anticancer activity was evaluated in an orthotopic pancreatic adenocarcinoma tumor bearing SCID beige mice, which confirmed that EGFR-targeted gelatin nanoparticles could efficiently deliver gemcitabine to the tumor leading to higher therapeutic benefit as compared to the drug in solution. The treatment of pancreatic cancer remains unsatisfactory, with an average 5-year survival of less than 5%. New treatment modalities are thus urgently needed. In this study, the authors presented their formulation of redox-responsive epidermal growth factor receptor (EGFR)-targeted type B gelatin nanoparticles as a carrier for gemcitabine. In-vitro and in-vivo experiments showed encouraging results. It is hoped that the findings would provide a novel and alternative drug delivery platform for the future. Copyright © 2015 Elsevier Inc. All rights reserved.

Mechanistic Distinctions between CHK1 and WEE1 Inhibition Guide the Scheduling of Triple Therapy with Gemcitabine.

PubMed

Koh, Siang-Boon; Wallez, Yann; Dunlop, Charles R; Bernaldo de Quirós Fernández, Sandra; Bapiro, Tashinga E; Richards, Frances M; Jodrell, Duncan I

2018-06-01

Combination of cytotoxic therapy with emerging DNA damage response inhibitors (DDRi) has been limited by tolerability issues. However, the goal of most combination trials has been to administer DDRi with standard-of-care doses of chemotherapy. We hypothesized that mechanism-guided treatment scheduling could reduce the incidence of dose-limiting toxicities and enable tolerable multitherapeutic regimens. Integrative analyses of mathematical modeling and single-cell assays distinguished the synergy kinetics of WEE1 inhibitor (WEE1i) from CHEK1 inhibitor (CHK1i) by potency, spatiotemporal perturbation, and mitotic effects when combined with gemcitabine. These divergent properties collectively supported a triple-agent strategy, whereby a pulse of gemcitabine and CHK1i followed by WEE1i durably suppressed tumor cell growth. In xenografts, CHK1i exaggerated replication stress without mitotic CDK hyperactivation, enriching a geminin-positive subpopulation and intratumoral gemcitabine metabolite. Without overt toxicity, addition of WEE1i to low-dose gemcitabine and CHK1i was most effective in tumor control compared with single and double agents. Overall, our work provides quantitative insights into the mechanisms of DDRi chemosensitization, leading to the rational development of a tolerable multitherapeutic regimen. Significance: Multiple lines of mechanistic insight regarding DNA damage response inhibitors rationally guide the preclinical development of a tolerable multitherapeutic regimen. Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/11/3054/F1.large.jpg Cancer Res; 78(11); 3054-66. ©2018 AACR . ©2018 American Association for Cancer Research.

Inhibition of c-Myc by 10058-F4 induces growth arrest and chemosensitivity in pancreatic ductal adenocarcinoma.

PubMed

Zhang, Meng; Fan, Hai-Yan; Li, Sheng-Chao

2015-07-01

Pancreatic ductal adenocarcinoma (PDAC) is a formidable medical challenge due to its malignancies and the absence of effective treatment. c-Myc, as an important transcription factor, plays crucial roles in cell cycle progression, apoptosis and cellular transformation. The c-Myc inhibitor, 10058-F4, has been reported act as a tumor suppressor in several different tumors. In current study, the tumor-suppressive roles of 10058-F4 was observed in human pancreatic cancer cells in vitro as demonstrated by decreased cell viability, cell cycle arrest at the G1/S transition and increased caspase3/7 activity. And tumor responses to gemcitabine were also significantly enhanced by 10058-F4 in PANC-1 and SW1990 cells. In a subcutaneous xenograft model, however, 10058-F4 showed no significant influence on pancreatic tumorigenesis. When combined with gemcitabine, tumorigenesis was drastically attenuated compared with gemcitabine group or 10058-F4 group; this synergistic effect was accompanied with decreased PCNA-positive cells and reduced TUNEL-positive cells in the combined treated group. Subsequent studies revealed that decreased glycolysis may be involved in the inhibitory effect of 10058-F4 on PDAC. Taken together, this study demonstrates the roles of 10058-F4 in PDAC and provides evidence that 10058-F4 in combination with gemcitabine showed significant clinical benefit over the usage of gemcitabine alone. Copyright © 2015. Published by Elsevier Masson SAS.

Gemcitabine-cisplatin versus gemcitabine-oxaliplatin doublet chemotherapy in advanced gallbladder cancers: a match pair analysis.

PubMed

Ramaswamy, Anant; Ostwal, Vikas; Pinninti, Rakesh; Kannan, Sadhana; Bhargava, Prabhat; Nashikkar, Chaitali; Mirani, Jimmy; Banavali, Shripad

2017-05-01

Gemcitabine-cisplatin (GC) and gemcitabine-oxaliplatin (GO) are the most commonly used regimens in advanced gallbladder cancer (GBC). The data of patients with advanced GBC, treated between January 2013 and June 2015 were retrieved. A 1:1 matching without replacement was performed by using nearest neighbor matching method. A total of 326 patients (163 GC and 163 GO), were matched 1:1 by age and gender. The response rates for GC and GO were 31.2% and 36.3% (P = 0.350). The overall median event free survival (EFS) was 4.34 months (95% CI 4.030-4.644 months). The median EFS was 4.67 months (95% CI 4.060-5.271 months) in GC cohort and 3.88 months (95% CI 3.369-4.385 months) in GO cohort (P = 0.023). The overall median OS was 8.016 months (95% CI 7.361-8.672 months). The median OS was 8.02 months (95% CI 7.257-8.776 months) in GC cohort and 7.79 months (95% CI 6.690-8.88 months) in GO cohort (P = 0.455). The incidence of Grade 2/3 peripheral neuropathy (9.2% vs. 3.1%; P = 0.445) and Grade 3/4 transamintis (14.7% vs. 6.1%) was higher with GO while the incidence of anemia (22.1% vs. 6.7%; P < 0.001), neutropenia (7.3% vs. 2.4%; P = 0.49) and thrombocytopenia (9.8% vs. 3.7%; P = 0.033) was higher with GC. Gemcitabine-cisplatin or gemcitabine-oxaliplatin can be used as an initial regimen in advanced GBC. Higher EFS, potentially lower costs, lower incidence of peripheral neuropathy and hepatotoxicity favor the use of GC, whereas a lower incidence of hematological toxicities, and potential ease of administration in patients with borderline renal and cardiac functions favor GO. © 2017 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

Is the progression free survival advantage of concurrent gemcitabine plus cisplatin and radiation followed by adjuvant gemcitabine and cisplatin in patients with advanced cervical cancer worth the additional cost? A cost-effectiveness analysis.

PubMed

Smith, B; Cohn, D E; Clements, A; Tierney, B J; Straughn, J M

2013-09-01

The objective of this study is to determine whether concurrent and adjuvant chemoradiation with gemcitabine/cisplatin is cost-effective in patients with stage IIB to IVA cervical cancer. A cost-effectiveness model compared two arms of the trial performed by Duenas-Gonzalez et al. [1]: concurrent and adjuvant chemoradiation with gemcitabine/cisplatin (RT/GC+GC) versus concurrent radiation with cisplatin (RT/C). Major adverse events (AEs) and progression free survival (PFS) rates of each arm were incorporated in the model. AEs were defined as any hospitalization including grade 4 anemia, grade 4 neutropenia, and death. Medicare data and literature review were used to estimate costs. Incremental cost-effectiveness ratios (ICERs) per progression-free life-year saved (PF-LYS) were calculated. Sensitivity analyses were performed for pertinent uncertainties. For 10,000 women with locally advanced cervical cancer, the cost of therapy and AEs was $173.9 million (M) for RT/C versus $259.8M for RT/GC+GC. There were 879 additional 3-year progression-free survivors in the RT/GC+GC arm. The ICER for RT/GC+GC was $97,799 per PF-LYS. When the rate of hospitalization was equalized to 4.3%, the ICER for RT/GC+GC exceeded $80,000. The resultant ICER when increasing PFS in the RT/GC+GC arm by 5% was $62,605 per PF-LYS. When the cost of chemotherapy was decreased by 50%, the ICER was below $50,000 at $41,774 per PF-LYS. Radiation and gemcitabine/cisplatin for patients with stage IIB to IVA cervical cancer are not cost-effective. The increased financial burden of radiation with gemcitabine/cisplatin and associated toxicities appears to outweigh the benefit of increased 3-year PFS and is primarily dependent on chemotherapy drug costs. Copyright © 2013 Elsevier Inc. All rights reserved.

Overexpression of heat shock protein 27 (HSP27) increases gemcitabine sensitivity in pancreatic cancer cells through S-phase arrest and apoptosis.

PubMed

Guo, Yang; Ziesch, Andreas; Hocke, Sandra; Kampmann, Eric; Ochs, Stephanie; De Toni, Enrico N; Göke, Burkhard; Gallmeier, Eike

2015-02-01

We previously established a role for HSP27 as a predictive marker for therapeutic response towards gemcitabine in pancreatic cancer. Here, we investigate the underlying mechanisms of HSP27-mediated gemcitabine sensitivity. Utilizing a pancreatic cancer cell model with stable HSP27 overexpression, cell cycle arrest and apoptosis induction were analysed by flow cytometry, nuclear staining, immunoblotting and mitochondrial staining. Drug sensitivity studies were performed by proliferation assays. Hyperthermia was simulated using mild heat shock at 41.8°C. Upon gemcitabine treatment, HSP27-overexpressing cells displayed an early S-phase arrest subsequently followed by a strongly increased sub-G1 fraction. Apoptosis was characterized by PARP-, CASPASE 3-, CASPASE 8-, CASPASE 9- and BIM- activation along with a mitochondrial membrane potential loss. It was reversible through chemical caspase inhibition. Importantly, gemcitabine sensitivity and PARP cleavage were also elicited by heat shock-induced HSP27 overexpression, although to a smaller extent, in a panel of pancreatic cancer cell lines. Finally, HSP27-overexpressing pancreatic cancer cells displayed an increased sensitivity also towards death receptor-targeting agents, suggesting another pro-apoptotic role of HSP27 along the extrinsic apoptosis pathway. Taken together, in contrast to the well-established anti-apoptotic properties of HSP27 in cancer, our study reveals novel pro-apoptotic functions of HSP27-mediated through both the intrinsic and the extrinsic apoptotic pathways-at least in pancreatic cancer cells. HSP27 could represent a predictive marker of therapeutic response towards specific drug classes in pancreatic cancer and provides a novel molecular rationale for current clinical trials applying the combination of gemcitabine with regional hyperthermia in pancreatic cancer patients. © 2015 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

A novel method for quantification of gemcitabine and its metabolites 2',2'-difluorodeoxyuridine and gemcitabine triphosphate in tumour tissue by LC-MS/MS: comparison with (19)F NMR spectroscopy.

PubMed

Bapiro, Tashinga E; Richards, Frances M; Goldgraben, Mae A; Olive, Kenneth P; Madhu, Basetti; Frese, Kristopher K; Cook, Natalie; Jacobetz, Michael A; Smith, Donna-Michelle; Tuveson, David A; Griffiths, John R; Jodrell, Duncan I

2011-11-01

To develop a sensitive analytical method to quantify gemcitabine (2',2'-difluorodeoxycytidine, dFdC) and its metabolites 2',2'-difluorodeoxyuridine (dFdU) and 2',2'-difluorodeoxycytidine-5'-triphosphate (dFdCTP) simultaneously from tumour tissue. Pancreatic ductal adenocarcinoma tumour tissue from genetically engineered mouse models of pancreatic cancer (KP ( FL/FL ) C and KP ( R172H/+) C) was collected after dosing the mice with gemcitabine. (19)F NMR spectroscopy and LC-MS/MS protocols were optimised to detect gemcitabine and its metabolites in homogenates of the tumour tissue. A (19)F NMR protocol was developed, which was capable of distinguishing the three analytes in tumour homogenates. However, it required at least 100 mg of the tissue in question and a long acquisition time per sample, making it impractical for use in large PK/PD studies or clinical trials. The LC-MS/MS protocol was developed using porous graphitic carbon to separate the analytes, enabling simultaneous detection of all three analytes from as little as 10 mg of tissue, with a sensitivity for dFdCTP of 0.2 ng/mg tissue. Multiple pieces of tissue from single tumours were analysed, showing little intra-tumour variation in the concentrations of dFdC or dFdU (both intra- and extra-cellular). Intra-tumoural variation was observed in the concentration of dFdCTP, an intra-cellular metabolite, which may reflect regions of different cellularity within a tumour. We have developed a sensitive LC-MS/MS method capable of quantifying gemcitabine, dFdU and dFdCTP in pancreatic tumour tissue. The requirement for only 10 mg of tissue enables this protocol to be used to analyse multiple areas from a single tumour and to spare tissue for additional pharmacodynamic assays.

Adjuvant chemotherapy with fluorouracil plus folinic acid vs gemcitabine following pancreatic cancer resection: a randomized controlled trial.

PubMed

Neoptolemos, John P; Stocken, Deborah D; Bassi, Claudio; Ghaneh, Paula; Cunningham, David; Goldstein, David; Padbury, Robert; Moore, Malcolm J; Gallinger, Steven; Mariette, Christophe; Wente, Moritz N; Izbicki, Jakob R; Friess, Helmut; Lerch, Markus M; Dervenis, Christos; Oláh, Attila; Butturini, Giovanni; Doi, Ryuichiro; Lind, Pehr A; Smith, David; Valle, Juan W; Palmer, Daniel H; Buckels, John A; Thompson, Joyce; McKay, Colin J; Rawcliffe, Charlotte L; Büchler, Markus W

2010-09-08

Adjuvant fluorouracil has been shown to be of benefit for patients with resected pancreatic cancer. Gemcitabine is known to be the most effective agent in advanced disease as well as an effective agent in patients with resected pancreatic cancer. To determine whether fluorouracil or gemcitabine is superior in terms of overall survival as adjuvant treatment following resection of pancreatic cancer. The European Study Group for Pancreatic Cancer (ESPAC)-3 trial, an open-label, phase 3, randomized controlled trial conducted in 159 pancreatic cancer centers in Europe, Australasia, Japan, and Canada. Included in ESPAC-3 version 2 were 1088 patients with pancreatic ductal adenocarcinoma who had undergone cancer resection; patients were randomized between July 2000 and January 2007 and underwent at least 2 years of follow-up. Patients received either fluorouracil plus folinic acid (folinic acid, 20 mg/m(2), intravenous bolus injection, followed by fluorouracil, 425 mg/m(2) intravenous bolus injection given 1-5 days every 28 days) (n = 551) or gemcitabine (1000 mg/m(2) intravenous infusion once a week for 3 of every 4 weeks) (n = 537) for 6 months. Primary outcome measure was overall survival; secondary measures were toxicity, progression-free survival, and quality of life. Final analysis was carried out on an intention-to-treat basis after a median of 34.2 (interquartile range, 27.1-43.4) months' follow-up after 753 deaths (69%). Median survival was 23.0 (95% confidence interval [CI], 21.1-25.0) months for patients treated with fluorouracil plus folinic acid and 23.6 (95% CI, 21.4-26.4) months for those treated with gemcitabine (chi(1)(2) = 0.7; P = .39; hazard ratio, 0.94 [95% CI, 0.81-1.08]). Seventy-seven patients (14%) receiving fluorouracil plus folinic acid had 97 treatment-related serious adverse events, compared with 40 patients (7.5%) receiving gemcitabine, who had 52 events (P < .001). There were no significant differences in either progression-free survival or global quality-of-life scores between the treatment groups. Compared with the use of fluorouracil plus folinic acid, gemcitabine did not result in improved overall survival in patients with completely resected pancreatic cancer. clinicaltrials.gov Identifier: NCT00058201.

Pathogenetic role of the deafness-related M34T mutation of Cx26

PubMed Central

Bicego, Massimiliano; Beltramello, Martina; Melchionda, Salvatore; Carella, Massimo; Piazza, Valeria; Zelante, Leopoldo; Bukauskas, Feliksas F.; Arslan, Edoardo; Cama, Elona; Pantano, Sergio; Bruzzone, Roberto; D’Andrea, Paola; Mammano, Fabio

2010-01-01

Mutations in the GJB2 gene, which encodes the gap junction protein connexin26 (Cx26), are the major cause of genetic non-syndromic hearing loss. The role of the allelic variant M34T in causing hereditary deafness remains controversial. By combining genetic, clinical, biochemical, electrophysiological and structural modeling studies, we have re-assessed the pathogenetic role of the M34T mutation. Genetic and audiological data indicate that the majority of heterozygous carriers and all five compound heterozygotes exhibited an impaired auditory function. Functional expression in transiently transfected HeLa cells showed that, although M34T was correctly synthesized and targeted to the plasma membrane, it inefficiently formed intercellular channels that displayed an abnormal electrical behavior and retained only 11% of the unitary conductance of the wild-type protein (HCx26wt). Moreover, M34T channels failed to support the intercellular diffusion of Lucifer Yellow and the spreading of mechanically induced intercellular Ca2+ waves. When co-expressed together with HCx26wt, M34T exerted dominant-negative effects on cell–cell coupling. Our findings are consistent with a structural model, predicting that the mutation leads to a constriction of the channel pore. These data support the view that M34T is a pathological variant of Cx26 associated with hearing impairment. PMID:16849369

Investigation of the mechanism for penetration of low density lipoprotein into the arterial wall

NASA Astrophysics Data System (ADS)

Glukhova, O. E.; Zyktin, A. A.; Slepchenkov, M. M.

2018-02-01

Currently, the pathology of the cardiovascular system is an extremely urgent problem of fundamental and clinical medicine. These diseases are caused, mainly, by atherosclerotic changes in the wall of blood vessels. The predominant role in the development of atherosclerosis is attributed to the penetration of various kinds of lipoproteins into the arterial intima. In this paper, we in silico investigated the dynamics of the penetration of low density lipoprotein (LDL) through the intercellular gap using molecular modeling methods. The simulation was carried out in the GROMACS software package using a coarse-grained MARTINI model. During investigation we carried out the LDL self-assembly for the first time. The coarse-grained model of LDL was collected from the following molecules: POPC (phosphatidylcholine) - 630 molecules, LPC (lysophosphatidylcholine) - 80 molecules CHOL (cholesterol) - 600 molecules CHYO (cholesteryl oleate) - 1600 molecules TOG (glycerol trioleate) 180 Molecules. The coarse-grained model of the intercellular endothelial gap was based on a model of lipid bilayer consisting of DPPC phospholipids and cholesterol in a percentage ratio of 70% and 30%, respectively. Based on the obtained results, we can predict the mechanism of LDL diffusion. Lipoproteins can be deformed so as to pass through narrow gaps. Our investigations open the way for the research of the behavior dynamics of LDL moving with the blood flow rate when interacting with the intercellular gaps of the endothelial layer of the vessel inner wall.

Overexpression of SepJ alters septal morphology and heterocyst pattern regulated by diffusible signals in Anabaena.

PubMed

Mariscal, Vicente; Nürnberg, Dennis J; Herrero, Antonia; Mullineaux, Conrad W; Flores, Enrique

2016-09-01

Filamentous, N2 -fixing, heterocyst-forming cyanobacteria grow as chains of cells that are connected by septal junctions. In the model organism Anabaena sp. strain PCC 7120, the septal protein SepJ is required for filament integrity, normal intercellular molecular exchange, heterocyst differentiation, and diazotrophic growth. An Anabaena strain overexpressing SepJ made wider septa between vegetative cells than the wild type, which correlated with a more spread location of SepJ in the septa as observed with a SepJ-GFP fusion, and contained an increased number of nanopores, the septal peptidoglycan perforations that likely accommodate septal junctions. The septa between heterocysts and vegetative cells, which are narrow in wild-type Anabaena, were notably enlarged in the SepJ-overexpressing mutant. Intercellular molecular exchange tested with fluorescent tracers was increased for the SepJ-overexpressing strain specifically in the case of calcein transfer between vegetative cells and heterocysts. These results support an association between calcein transfer, SepJ-related septal junctions, and septal peptidoglycan nanopores. Under nitrogen deprivation, the SepJ-overexpressing strain produced an increased number of contiguous heterocysts but a decreased percentage of total heterocysts. These effects were lost or altered in patS and hetN mutant backgrounds, supporting a role of SepJ in the intercellular transfer of regulatory signals for heterocyst differentiation. © 2016 John Wiley & Sons Ltd.

Functional assessment of gap junctions in monolayer and three-dimensional cultures of human tendon cells using fluorescence recovery after photobleaching

PubMed Central

Kuzma-Kuzniarska, Maria; Yapp, Clarence; Pearson-Jones, Thomas W.; Jones, Andrew K.; Hulley, Philippa A.

2014-01-01

Abstract. Gap junction-mediated intercellular communication influences a variety of cellular activities. In tendons, gap junctions modulate collagen production, are involved in strain-induced cell death, and are involved in the response to mechanical stimulation. The aim of the present study was to investigate gap junction-mediated intercellular communication in healthy human tendon-derived cells using fluorescence recovery after photobleaching (FRAP). The FRAP is a noninvasive technique that allows quantitative measurement of gap junction function in living cells. It is based on diffusion-dependent redistribution of a gap junction-permeable fluorescent dye. Using FRAP, we showed that human tenocytes form functional gap junctions in monolayer and three-dimensional (3-D) collagen I culture. Fluorescently labeled tenocytes following photobleaching rapidly reacquired the fluorescent dye from neighboring cells, while HeLa cells, which do not communicate by gap junctions, remained bleached. Furthermore, both 18 β-glycyrrhetinic acid and carbenoxolone, standard inhibitors of gap junction activity, impaired fluorescence recovery in tendon cells. In both monolayer and 3-D cultures, intercellular communication in isolated cells was significantly decreased when compared with cells forming many cell-to-cell contacts. In this study, we used FRAP as a tool to quantify and experimentally manipulate the function of gap junctions in human tenocytes in both two-dimensional (2-D) and 3-D cultures. PMID:24390370

Induction gemcitabine in standard dose or prolonged low-dose with cisplatin followed by concurrent radiochemotherapy in locally advanced non-small cell lung cancer: a randomized phase II clinical trial

PubMed Central

Vrankar, Martina; Zwitter, Matjaz; Bavcar, Tanja; Milic, Ana; Kovac, Viljem

2014-01-01

Background The optimal combination of chemotherapy with radiation therapy for treatment locally advanced non-small cell lung cancer (NSCLC) remains an open issue. This randomized phase II study compared gemcitabine in two different schedules and cisplatin - as induction chemotherapy, followed by radiation therapy concurrent with cisplatin and etoposid. Patients and methods. Eligible patients had microscopically confirmed inoperable non-metastatic non-small cell lung cancer; fulfilled the standard criteria for platin-based chemotherapy; and signed informed consent. Patients were treated with 3 cycles of induction chemotherapy with gemcitabine and cisplatin. Two different aplications of gemcitabine were compared: patients in arm A received gemcitabine at 1250 mg/m2 in a standard half hour i.v. infusion on days 1 and 8; patients in arm B received gemcitabine at 250 mg/m2 in prolonged 6-hours i.v. infusion on days 1 and 8. In both arms, cisplatin 75 mg/m2 on day 2 was administered. All patients continued treatment with radiation therapy with 60–66 Gy concurrent with cisplatin 50 mg/m2 on days 1, 8, 29 and 36 and etoposid 50 mg/m2 on days 1–5 and 29–33. The primary endpoint was response rate (RR) after induction chemotherapy; secondary endpoints were toxicity, progression-free survival (PFS) and overall survival (OS). Results From September 2005 to November 2010, 106 patients were recruited to this study. No statistically signifficant differences were found in RR after induction chemotherapy between the two arms (48.1% and 57.4%, p = 0.34). Toxicity profile was comparable and mild with grade 3/4 neutropenia as primary toxicity in both arms. One patient in arm B suffered from acute peripheral ischemia grade 4 and an amputation of lower limb was needed. With a median follow-up of 69.3 months, progression-free survival and median survival in arm A were 15.7 and 24.8 months compared to 18.9 and 28.6 months in arm B. The figures for 1- and 3-year overall survival were 73.1% and 30.8% in arm A, and 81.5 % and 44.4% in arm B, respectively. Conclusions Among the two cisplatin-based doublets of induction chemotherapy for inoperable NSCLC, both schedules of gemcitabine have a comparable toxicity profile. Figures for RR, PFS and OS are among the best reported in current literature. While there is a trend towards better efficacy of the treament with prolonged infusion of gemcitabine, the difference between the two arms did not reach statistical significance. PMID:25435850

Regulation of Endothelial Adherens Junctions by Tyrosine Phosphorylation

PubMed Central

Adam, Alejandro Pablo

2015-01-01

Endothelial cells form a semipermeable, regulated barrier that limits the passage of fluid, small molecules, and leukocytes between the bloodstream and the surrounding tissues. The adherens junction, a major mechanism of intercellular adhesion, is comprised of transmembrane cadherins forming homotypic interactions between adjacent cells and associated cytoplasmic catenins linking the cadherins to the cytoskeleton. Inflammatory conditions promote the disassembly of the adherens junction and a loss of intercellular adhesion, creating openings or gaps in the endothelium through which small molecules diffuse and leukocytes transmigrate. Tyrosine kinase signaling has emerged as a central regulator of the inflammatory response, partly through direct phosphorylation and dephosphorylation of the adherens junction components. This review discusses the findings that support and those that argue against a direct effect of cadherin and catenin phosphorylation in the disassembly of the adherens junction. Recent findings indicate a complex interaction between kinases, phosphatases, and the adherens junction components that allow a fine regulation of the endothelial permeability to small molecules, leukocyte migration, and barrier resealing. PMID:26556953

Plasmodesmata in integrated cell signalling: insights from development and environmental signals and stresses

PubMed Central

Sager, Ross; Lee, Jung-Youn

2014-01-01

To survive as sedentary organisms built of immobile cells, plants require an effective intercellular communication system, both locally between neighbouring cells within each tissue and systemically across distantly located organs. Such a system enables cells to coordinate their intracellular activities and produce concerted responses to internal and external stimuli. Plasmodesmata, membrane-lined intercellular channels, are essential for direct cell-to-cell communication involving exchange of diffusible factors, including signalling and information molecules. Recent advances corroborate that plasmodesmata are not passive but rather highly dynamic channels, in that their density in the cell walls and gating activities are tightly linked to developmental and physiological processes. Moreover, it is becoming clear that specific hormonal signalling pathways play crucial roles in relaying primary cellular signals to plasmodesmata. In this review, we examine a number of studies in which plasmodesmal structure, occurrence, and/or permeability responses are found to be altered upon given cellular or environmental signals, and discuss common themes illustrating how plasmodesmal regulation is integrated into specific cellular signalling pathways. PMID:25262225

Astrocytes and extracellular matrix in extrasynaptic volume transmission.

PubMed

Vargová, Lýdia; Syková, Eva

2014-10-19

Volume transmission is a form of intercellular communication that does not require synapses; it is based on the diffusion of neuroactive substances across the brain extracellular space (ECS) and their binding to extrasynaptic high-affinity receptors on neurons or glia. Extracellular diffusion is restricted by the limited volume of the ECS, which is described by the ECS volume fraction α, and the presence of diffusion barriers, reflected by tortuosity λ, that are created, for example, by fine astrocytic processes or extracellular matrix (ECM) molecules. Organized astrocytic processes, ECM scaffolds or myelin sheets channel the extracellular diffusion so that it is facilitated in a certain direction, i.e. anisotropic. The diffusion properties of the ECS are profoundly influenced by various processes such as the swelling and morphological rebuilding of astrocytes during either transient or persisting physiological or pathological states, or the remodelling of the ECM in tumorous or epileptogenic tissue, during Alzheimer's disease, after enzymatic treatment or in transgenic animals. The changing diffusion properties of the ECM influence neuron-glia interaction, learning abilities, the extent of neuronal damage and even cell migration. From a clinical point of view, diffusion parameter changes occurring during pathological states could be important for diagnosis, drug delivery and treatment. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Corruption of the Fas Pathway Delays the Pulmonary Clearance of Murine Osteosarcoma Cells, Enhances Their Metastatic Potential, and Reduces the Effect of Aerosol Gemcitabine

PubMed Central

Gordon, Nancy; Koshkina, Nadezhda V.; Jia, Shu-Fang; Khanna, Chand; Mendoza, Arnulfo; Worth, Laura L.; Kleinerman, Eugenie S.

2015-01-01

Purpose Pulmonary metastases continue to be a significant problem in osteosarcoma. Apoptosis dysfunction is known to influence tumor development. Fas (CD95, APO-1)/FasL is one of the most extensively studied apoptotic pathways. Because FasL is constitutively expressed in the lung, cells that express Fas should be eliminated by lung endothelium. Cells with low or no cell surface Fas expression may be able to evade this innate defense mechanism. The purpose of these studies was to evaluate Fas expression in osteosarcoma lung metastases and the effect of gemcitabine on Fas expression and tumor growth. Experimental Design and Results Using the K7M2 murine osteosarcoma model, Fas expression was quantified using immunohistochemistry. High levels of Fas were present in primary tumors, but no Fas expression was present in actively growing lung metastases. Blocking the Fas pathway using Fas-associated death domain dominant-negative delayed tumor cell clearance from the lung and increased metastatic potential. Treatment of mice with aerosol gemcitabine resulted in increased Fas expression and subsequent tum or regression. Conclusions We conclude that corruption of the Fas pathway is critical to the ability of osteosarcoma cells to grow in the lung. Agents such as gemcitabine that up-regulate cell surface Fas expression may therefore be effective in treating osteosarcoma lung metastases. These data also suggest that an additional mechanism by which gemcitabine induces regression of osteosarcoma lung metastases is mediated by enhancing the sensitivity of the tumor cells to the constitutive FasL in the lung. PMID:17671136

Sulforaphane inhibits growth of human breast cancer cells and augments the therapeutic index of the chemotherapeutic drug, gemcitabine.

PubMed

Hussain, Arif; Mohsin, Javeria; Prabhu, Sathyen Alwin; Begum, Salema; Nusri, Qurrat El-Ain; Harish, Geetganga; Javed, Elham; Khan, Munawwar Ali; Sharma, Chhavi

2013-01-01

Phytochemicals are among the natural chemopreventive agents with most potential for delaying, blocking or reversing the initiation and promotional events of carcinogenesis. They therefore offer cancer treatment strategies to reduce cancer related death. One such promising chemopreventive agent which has attracted considerable attention is sulforaphane (SFN), which exhibits anti-cancer, anti-diabetic, and anti-microbial properties. The present study was undertaken to assess effect of SFN alone and in combination with a chemotherapeutic agent, gemcitabine, on the proliferative potential of MCF-7 cells by cell viability assay and authenticated the results by nuclear morphological examination. Further we analyzed the modulation of expression of Bcl-2 and COX-2 on treatment of these cells with SFN by RT-PCR. SFN showed cytotoxic effects on MCF-7 cells in a dose- and time-dependent manner via an apoptotic mode of cell death. In addition, a combinational treatment of SFN and gemcitabine on MCF-7 cells resulted in growth inhibition in a synergistic manner with a combination index (CI) <1. Notably, SFN was found to significantly downregulate the expression of Bcl-2, an anti-apoptotic gene, and COX-2, a gene involved in inflammation, in a time-dependent manner. These results indicate that SFN induces apoptosis and anti-inflammatory effects on MCF-7 cells via downregulation of Bcl-2 and COX-2 respectively. The combination of SFN and gemcitabine may potentiate the efficacy of gemcitabine and minimize the toxicity to normal cells. Taken together, SFN may be a potent anti-cancer agent for breast cancer treatment.

Lurbinectedin induces depletion of tumor-associated macrophages, an essential component of its in vivo synergism with gemcitabine, in pancreatic adenocarcinoma mouse models

PubMed Central

Céspedes, María Virtudes; Guillén, María José; López-Casas, Pedro Pablo; Sarno, Francesca; Gallardo, Alberto; Álamo, Patricia; Cuevas, Carmen; Hidalgo, Manuel; Galmarini, Carlos María; Allavena, Paola; Avilés, Pablo; Mangues, Ramón

2016-01-01

ABSTRACT We explored whether the combination of lurbinectedin (PM01183) with the antimetabolite gemcitabine could result in a synergistic antitumor effect in pancreatic ductal adenocarcinoma (PDA) mouse models. We also studied the contribution of lurbinectedin to this synergism. This drug presents a dual pharmacological effect that contributes to its in vivo antitumor activity: (i) specific binding to DNA minor grooves, inhibiting active transcription and DNA repair; and (ii) specific depletion of tumor-associated macrophages (TAMs). We evaluated the in vivo antitumor activity of lurbinectedin and gemcitabine as single agents and in combination in SW-1990 and MIA PaCa-2 cell-line xenografts and in patient-derived PDA models (AVATAR). Lurbinectedin-gemcitabine combination induced a synergistic effect on both MIA PaCa-2 [combination index (CI)=0.66] and SW-1990 (CI=0.80) tumor xenografts. It also induced complete tumor remissions in four out of six patient-derived PDA xenografts. This synergism was associated with enhanced DNA damage (anti-γ-H2AX), cell cycle blockage, caspase-3 activation and apoptosis. In addition to the enhanced DNA damage, which is a consequence of the interaction of the two drugs with the DNA, lurbinectedin induced TAM depletion leading to cytidine deaminase (CDA) downregulation in PDA tumors. This effect could, in turn, induce an increase of gemcitabine-mediated DNA damage that was especially relevant in high-density TAM tumors. These results show that lurbinectedin can be used to develop ‘molecularly targeted’ combination strategies. PMID:27780828

Combination chemotherapy with irinotecan and gemcitabine for taxane/platinum-resistant/refractory ovarian and primary peritoneal cancer: a multicenter phase I/II trial (GOGO-Ov 6).

PubMed

Yoshino, Kiyoshi; Kamiura, Shoji; Yokoi, Takeshi; Nakae, Ruriko; Fujita, Masami; Takemura, Masahiko; Adachi, Kazushige; Wakimoto, Akinori; Nishizaki, Takamichi; Shiki, Yasuhiko; Tsutsui, Tateki; Kanda, Yuki; Kobayashi, Eiji; Hashimoto, Kae; Mabuchi, Seiji; Ueda, Yutaka; Sawada, Kenjiro; Tomimatsu, Takuji; Kimura, Tadashi

2017-12-01

To develop a new therapeutic strategy for taxane/platinum-resistant/refractory ovarian and primary peritoneal cancers, we evaluated the feasibility and efficacy of irinotecan and gemcitabine combination chemotherapy. Patients with taxane/platinum-resistant/refractory cancer received escalating doses of irinotecan and gemcitabine (level 1: 80 and 800 mg/m 2 , respectively; level 2: 100 and 1000 mg/m 2 ) on days 1 and 8 on a 21-day cycle. Genotyping for UGT1A1*6 and *28 polymorphisms was performed for possible adverse irinotecan sensitivity. A total of 35 patients were enrolled. The recommended dose was defined as 100 mg/m 2 irinotecan and 1000 mg/m 2 gemcitabine (level 2). The observed common grade 3/4 toxicities were neutropenia (60%), anemia (17.1%), diarrhea (8.6%), thrombocytopenia (5.7%) and nausea (5.7%). Groups homozygous for UGT1A1*6 or *28 were associated with grade 3/4 neutropenia and diarrhea. Objective responses were 20%, including one complete response and six partial responses. In 29 patients treated with the recommended dose, the median progression-free survival and overall survival were 3.8 months (95% CI 2.1-6.0 months) and 17.4 months (95% CI 9.9-21.9 months), respectively, while the 1-year survival rate was 58.6%. Combination chemotherapy with irinotecan and gemcitabine represents a safe and effective treatment combination for taxane/platinum-resistant/refractory ovarian and primary peritoneal cancers.

A first-in-human phase I and pharmacokinetic study of CP-4126 (CO-101), a nucleoside analogue, in patients with advanced solid tumours.

PubMed

Venugopal, B; Awada, A; Evans, T R J; Dueland, S; Hendlisz, A; Rasch, W; Hernes, K; Hagen, S; Aamdal, S

2015-10-01

CP-4126 (gemcitabine elaidate, previously CO-101) is a lipid-drug conjugate of gemcitabine designed to circumvent human equilibrative nucleoside transporter1-related resistance to gemcitabine. The purpose of this study was to determine the maximum tolerated dose (MTD) and the recommended phase II dose (RP2D) of CP-4126, and to describe its pharmacokinetic profile. Eligible patients with advanced refractory solid tumours, and adequate performance status, haematological, renal and hepatic function, were treated with one of escalating doses of CP-4126 administered by a 30-min intravenous infusion on days 1, 8 and 15 of a 28-day cycle. Blood and urine samples were collected to determine the pharmacokinetics (PKs) of CP-4126. Forty-three patients, median age 59 years (range 18-76; male = 27, female = 16), received one of ten dose levels (30-1600 mg/m(2)). Dose-limiting toxicities included grade 3 anaemia, grade 3 fatigue and grade 3 elevation of transaminases. The MTD and RP2D were 1250 mg/m(2) on basis of the toxicity and PK data. CP-4126 followed dose-dependent kinetics and maximum plasma concentrations occurred at the end of CP-4126 infusion. Seven patients achieved stable disease sustained for ≥3 months, including two patients with pancreatic cancer who had progressed on or after gemcitabine exposure. CP-4126 was well tolerated with comparable toxicity profile to gemcitabine. Future studies are required to determine its anti-tumour efficacy, either alone or in combination with other cytotoxic chemotherapy regimens.

Self-assembled gemcitabine-gadolinium nanoparticles for magnetic resonance imaging and cancer therapy.

PubMed

Li, Lele; Tong, Rong; Li, Mengyuan; Kohane, Daniel S

2016-03-01

Nanoparticles with combined diagnostic and therapeutic functions are promising tools for cancer diagnosis and treatment. Here, we demonstrate a theranostic nanoparticle that integrates an active gemcitabine metabolite and a gadolinium-based magnetic resonance imaging agent via a facile supramolecular self-assembly synthesis, where the anti-cancer drug gemcitabine-5'-monophosphate (a phosphorylated active metabolite of the anti-cancer drug gemcitabine) was used to coordinate with Gd(III) to self-assemble into theranostic nanoparticles. The formulation exhibits a strong T1 contrast signal for magnetic resonance imaging of tumors in vivo, with enhanced retention time. Furthermore, the nanoparticles did not require other inert nanocarriers or excipients and thus had an exceptionally high drug loading (55 wt%), resulting in the inhibition of MDA-MB-231 tumor growth in mice. Recent advances in nanoparticle-based drug delivery systems have spurred the development of "theranostic" multifunctional nanoparticles, which combine therapeutic and diagnostic functionalities in a single formulation. Developing simple and efficient synthetic strategies for the construction of nanotheranostics with high drug loading remains a challenge. Here, we demonstrate a theranostic nanoparticle that integrates high loadings of an active gemcitabine metabolite and a gadolinium-based magnetic resonance imaging agent via a facile synthesis. The nanoparticles were better T1 contrast agents than currently used Gd-DTPA and had prolonged retention in tumor. Moreover they exhibited enhanced in vivo antitumor activity compared to free drug in a breast cancer xenograft mouse model. The strategy provides a scalable way to fabricate nanoparticles that enables enhancement of both therapeutic and diagnostic capabilities. Published by Elsevier Ltd.

Evaluate Risk/Benefit of Nab Paclitaxel in Combination With Gemcitabine and Carboplatin Compared to Gemcitabine and Carboplatin in Triple Negative Metastatic Breast Cancer (or Metastatic Triple Negative Breast Cancer)

ClinicalTrials.gov

2018-03-07

Breast Tumor; Breast Cancer; Cancer of the Breast; Estrogen Receptor- Negative Breast Cancer; HER2- Negative Breast Cancer; Progesterone Receptor- Negative Breast Cancer; Recurrent Breast Cancer; Stage IV Breast Cancer; Triple-negative Breast Cancer; Triple-negative Metastatic Breast Cancer; Metastatic Breast Cancer

Therapeutic Potential of Curcumin in Treatment of Pancreatic Cancer: Current Status and Future Perspectives.

PubMed

Hosseini, Mina; Hassanian, Seyed Mahdi; Mohammadzadeh, Elham; ShahidSales, Soodabeh; Maftouh, Mina; Fayazbakhsh, Hasan; Khazaei, Majid; Avan, Amir

2017-07-01

Pancreatic cancer is among the leading cause of deaths due to cancer with extremely poor prognosis. Gemcitabine is being used in the treatment of patient with pancreatic ductal adenocarcinoma (PDAC), although, the response rate is bellow 12%. A recent phase III trial revealed that FOLFIRINOX could be an option for the treatment of metastatic PDAC patients, although it is associated with increased toxicity. Therefore, identification of novel agents that either improves gemcitabine activity, within novel combinatorial approaches, or with a better efficacy than gemcitabine is warranted. The antitumor activity of curcumin in several tumors, including prostate, breast and colorectal cancers have investigated. A recent phase II trial explored the effects of curcumin in advanced pancreatic cancer patient. They found that oral curcumin was well tolerated. Another trial showed the activity of 8,000 mg of curcumin in combination with gemcitabine in patients with advanced pancreatic cancer. This review summarizes the current knowledge about possible molecular mechanisms of curcumin in PDAC with particular emphasis on preclinical/clinical studies in pancreatic cancer treatment. J. Cell. Biochem. 118: 1634-1638, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Systemic therapy for unresectable and metastatic transitional cell carcinoma of the urothelium: first-line and beyond.

PubMed

Cheng, Tina

2008-09-01

The review aims to provide an overview of recent advances and future research direction in the management of patients with advanced transitional cell carcinoma. Early data of the randomized phase III study comparing paclitaxel, cisplatin, and gemcitabine with gemcitabine plus cisplatin for advanced urothelial cancer detected no survival difference. A phase II study investigated the safety and efficacy of trastuzumab, carboplatin, gemcitabine, and paclitaxel in human epidermal growth factor receptor-2/neu-positive advanced urothelial carcinoma and reported promising results. Renal-sparing regimens are under active development. A nonrandomized comparison of the 3-week with the 4-week schedule for gemcitabine and cisplatin showed that the 3-week schedule had less hematological toxicity and better dose intensity. Potential molecular markers such as excision repair cross-complementation group 1, emmprin, and survivin for survival and/or platinum resistance in patients with transitional cell carcinoma showed promise. Recent data do not support change in the current standard of care for advanced transitional cell carcinoma. Clinical testing of emerging anticancer therapies using new agents, new combinations, and new approaches is under active investigation. Rational combination and new strategy in clinical trial design are critical for new drug development for transitional cell carcinoma.

Towards an optimal treatment algorithm for metastatic pancreatic ductal adenocarcinoma (PDA)

PubMed Central

Uccello, M.; Moschetta, M.; Mak, G.; Alam, T.; Henriquez, C. Murias; Arkenau, H.-T.

2018-01-01

Chemotherapy remains the mainstay of treatment for advanced pancreatic ductal adenocarcinoma (pda). Two randomized trials have demonstrated superiority of the combination regimens folfirinox (5-fluorouracil, leucovorin, oxaliplatin, and irinotecan) and gemcitabine plus nab-paclitaxel over gemcitabine monotherapy as a first-line treatment in adequately fit subjects. Selected pda patients progressing to first-line therapy can receive secondline treatment with moderate clinical benefit. Nevertheless, the optimal algorithm and the role of combination therapy in second-line are still unclear. Published second-line pda clinical trials enrolled patients progressing to gemcitabine-based therapies in use before the approval of nab-paclitaxel and folfirinox. The evolving scenario in second-line may affect the choice of the first-line treatment. For example, nanoliposomal irinotecan plus 5-fluouracil and leucovorin is a novel second-line option which will be suitable only for patients progressing to gemcitabine-based therapy. Therefore, clinical judgement and appropriate patient selection remain key elements in treatment decision. In this review, we aim to illustrate currently available options and define a possible algorithm to guide treatment choice. Future clinical trials taking into account sequential treatment as a new paradigm in pda will help define a standard algorithm. PMID:29507500

MUC4 down-regulation reverses chemoresistance of pancreatic cancer stem/progenitor cells and their progenies.

PubMed

Mimeault, Murielle; Johansson, Sonny L; Senapati, Shantibhusan; Momi, Navneet; Chakraborty, Subhankar; Batra, Surinder K

2010-09-01

The present study was undertaken to estimate the therapeutic benefit to down-regulate the MUC4 mucin for reversing chemoresistance of pancreatic cancer (PC) stem/progenitor cells and their progenies. The results have revealed that MUC4 mucin is overexpressed in CD133(+) and CD133(-) pancreatic cells (PCs) detected in patient's adenocarcinoma tissues while no significant expression was seen in normal pancreatic tissues. The gain- and loss-of-function analyses have indicated that the overexpression of MUC4 in PC lines is associated with a higher resistance to the anti-proliferative, anti-invasive and apoptotic effects induced by gemcitabine. Importantly, the treatment of the MUC4-overexpressing CD18/HPAF-Src cells with gemcitabine resulted in an enrichment of the side population (SP) cells expressing CD133 while the total PC cells including non-SP cells detected in MUC4 knockdown CD18/HPAF-shMUC4 cells were responsive to the cytotoxic effects induced by gemcitabine. These data suggest that the MUC4 down-regulation may constitute a potential therapeutic strategy for improving the efficacy of gemcitabine to eradicate the total PC cell mass, and thereby preventing disease relapse. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Management of advanced pancreatic cancer with gemcitabine plus erlotinib: efficacy and safety results in clinical practice.

PubMed

Diaz Beveridge, Robert; Alcolea, Vicent; Aparicio, Jorge; Segura, Ángel; García, Jose; Corbellas, Miguel; Fonfría, María; Giménez, Alejandra; Montalar, Joaquin

2014-01-10

The combination of gemcitabine and erlotinib is a standard first-line treatment for unresectable, locally advanced or metastatic pancreatic cancer. We reviewed our single centre experience to assess its efficacy and toxicity in clinical practice. Clinical records of patients with unresectable, locally advanced or metastatic pancreatic cancer who were treated with the combination of gemcitabine and erlotinib were reviewed. Univariate survival analysis and multivariate analysis were carried out to indentify independent predictors factors of overall survival. Our series included 55 patients. Overall disease control rate was 47%: 5% of patients presented complete response, 20% partial response and 22% stable disease. Median overall survival was 8.3 months). Cox regression analysis indicated that performance status and locally advanced versus metastatic disease were independent factors of overall survival. Patients who developed acne-like rash toxicity, related to erlotinib administration, presented a higher survival than those patients who did not develop this toxicity. Gemcitabine plus erlotinib doublet is active in our series of patients with advanced pancreatic cancer. This study provides efficacy and safety results similar to those of the pivotal phase III clinical trial that tested the same combination.

Gemcitabine-induced hemolytic uremic syndrome mimicking scleroderma renal crisis presenting with Raynaud's phenomenon, positive antinuclear antibodies and hypertensive emergency.

PubMed

Yamada, Yuichiro; Suzuki, Keisuke; Nobata, Hironobu; Kawai, Hirohisa; Wakamatsu, Ryo; Miura, Naoto; Banno, Shogo; Imai, Hirokazu

2014-01-01

A 58-year-old woman who received gemcitabine for advanced gallbladder cancer developed an impaired renal function, thrombocytopenia, Raynaud's phenomenon, digital ischemic changes, a high antinuclear antibody titer and hypertensive emergency that mimicked a scleroderma renal crisis. A kidney biopsy specimen demonstrated onion-skin lesions in the arterioles and small arteries along with ischemic changes in the glomeruli, compatible with a diagnosis of hypertensive emergency (malignant hypertension). The intravenous administration of a calcium channel blocker, the oral administration of an angiotensin-converting enzyme inhibitor and angiotensin II receptor blocker and the transfusion of fresh frozen plasma were effective for treating the thrombocytopenia and progressive kidney dysfunction. Gemcitabine induces hemolytic uremic syndrome with accelerated hypertension and Raynaud's phenomenon, mimicking scleroderma renal crisis.

Cell wall properties in Oryza sativa influence mesophyll CO2 conductance.

PubMed

Ellsworth, Patrícia V; Ellsworth, Patrick Z; Koteyeva, Nuria K; Cousins, Asaph B

2018-04-20

Diffusion of CO 2 from the leaf intercellular air space to the site of carboxylation (g m ) is a potential trait for increasing net rates of CO 2 assimilation (A net ), photosynthetic efficiency, and crop productivity. Leaf anatomy plays a key role in this process; however, there are few investigations into how cell wall properties impact g m and A net . Online carbon isotope discrimination was used to determine g m and A net in Oryza sativa wild-type (WT) plants and mutants with disruptions in cell wall mixed-linkage glucan (MLG) production (CslF6 knockouts) under high- and low-light growth conditions. Cell wall thickness (T cw ), surface area of chloroplast exposed to intercellular air spaces (S c ), leaf dry mass per area (LMA), effective porosity, and other leaf anatomical traits were also analyzed. The g m of CslF6 mutants decreased by 83% relative to the WT, with c. 28% of the reduction in g m explained by S c . Although A net /LMA and A net /Chl partially explained differences in A net between genotypes, the change in cell wall properties influenced the diffusivity and availability of CO 2 . The data presented here indicate that the loss of MLG in CslF6 plants had an impact on g m and demonstrate the importance of cell wall effective porosity and liquid path length on g m . © 2018 The Authors. New Phytologist © 2018 New Phytologist Trust.

N-trimethyl chitosan nanoparticles and CSKSSDYQC peptide: N-trimethyl chitosan conjugates enhance the oral bioavailability of gemcitabine to treat breast cancer.

PubMed

Chen, Guanyu; Svirskis, Darren; Lu, Weiyue; Ying, Man; Huang, Yuan; Wen, Jingyuan

2018-05-10

Gemcitabine is a nucleoside analogue effective against a number of cancers. However, the full potential of this drug has not been realised, in part due to low oral bioavailability and frequent dosing requirements. This study reports the synthesis, in-vitro, ex-vivo and in-vivo evaluation of trimethyl chitosan (TMC) - CSKSSDYQC (CSK) peptide conjugates capable of enhancing the oral bioavailability of gemcitabine due to the ability to target intestinal goblet cells and promote intestinal cellular uptake. TMC was synthesized by a novel two-step methylation method to improve quanternization and yield. The CSK-TMC conjugates were prepared by ionic gelation to achieve particles sized at 173.6 ± 6.8 nm, zeta potential of +18.5 ± 0.2 mV and entrapment efficiency of 66.4 ± 0.1%, capable of sustained drug release. By encapsulating gemcitabine into CSK-TMC conjugates, an increased amount of drug permeated through porcine intestinal epithelial membranes compared with the unconjugated TMC nanoparticles (NPs). The rate of cellular uptake of drug loaded conjugates into HT29-MTX-E12 intestinal goblet cells, was time- and concentration-dependant. The conjugates underwent active transport associated with adsorptive mediated, clathrin and caveolae mediated endocytosis. In cellular transport studies, drug loaded conjugates had greater drug transport capability compared with drug solution and TMC NPs over the co-cultured Caco-2/HT29-MTX-E12 cell monolayer. The drug loaded conjugates exhibited electrostatic interaction with the intestinal epithelial cells. Both P-glycoprotein (P-gp) and multiple resistance protein-2 (MRP2) efflux affected the cellular transport of the conjugates. Importantly, during the pharmacokinetic studies, the orally administrated drug loaded into TMC NPs showed an improved oral bioavailability of 54.0%, compared with gemcitabine solution of 9.9%. Notable, the CSK-TMC conjugates further improved oral bioavailability to 60.1% and reduced the tumour growth rate in a BALB/c nude mouse model, with a 5.1-fold and 3.3-fold reduction compare with the non-treated group and gemcitabine solution group. Furthermore, no major evidence of toxicity was discernible on histologic studies of selected organs. In conclusion, the presented CSK-TMC conjugates and TMC nanoparticles both significantly improve the oral bioavailability of gemcitabine and have the potential for the treatment of breast cancer. Copyright © 2018 Elsevier B.V. All rights reserved.

Tripartite differentiation (squamous, glandular, and melanocytic) of a primary cutaneous neuroendocrine carcinoma. An immunocytochemical and ultrastructural study.

PubMed

Isimbaldi, G; Sironi, M; Taccagni, G; Declich, P; Dell'Antonio, A; Galli, C

1993-06-01

We report a case of primary cutaneous neuroendocrine carcinoma (PCNEC) with squamous, glandular, and melanocytic differentiation and associated Bowen disease. The paranuclear globular positivity of low-molecular-weight cytokeratins agrees with the ultrastructural observations of paranuclear fibrous bodies in the small neuroendocrine cells, while the diffuse cytoplasmic positivity corresponds to the sparse intermediate filaments in large cells with squamous differentiation. "Transitional forms" are characterized by both diffuse and globular cytoplasmic positivity for cytokeratins and by the ultrastructural evidence of neuroendocrine and squamous features. Therefore the ultrastructural demonstration of intracytoplasmic tonofibrils and tonofilaments, intercellular glandular lumina, lined by well-formed microvilli, and immature premelanosomes in the neurosecretory cells supports the proposed tripartite differentiation of neuroendocrine cells of this case of PCNEC.

Translating the ABC-02 trial into daily practice: outcome of palliative treatment in patients with unresectable biliary tract cancer treated with gemcitabine and cisplatin.

PubMed

Dierks, J; Gaspersz, M P; Belkouz, A; van Vugt, J L A; Coelen, R J S; de Groot, J W B; Ten Tije, A J; Meijer, W G; Pruijt, J F M; van Voorthuizen, T; van Spronsen, D J; Rentinck, M; Ten Oever, D; Smit, J M; Otten, H M; van Gulik, T M; Wilmink, J W; Groot Koerkamp, B; Klümpen, H

2017-12-21

Biliary tract cancer (BTC) is an uncommon cancer with an unfavorable prognosis. Since 2010, the standard of care for patients with unresectable BTC is palliative treatment with gemcitabine plus cisplatin, based on the landmark phase III ABC-02 trial. This current study aims to evaluate the efficacy and safety of gemcitabine and cisplatin in patients with unresectable cholangiocarcinoma and gallbladder cancer in daily practice that meet the criteria for the ABC-02 trial in comparison to patients who did not. Patients diagnosed with unresectable BTC between 2010 and 2015 with an indication for gemcitabine and cisplatin were included. We divided these patients into three groups: (I) patients who received chemotherapy and met the criteria of the ABC-02 trial, (II) patients who received chemotherapy and did not meet these criteria and (III) patients who had an indication for chemotherapy, but received best supportive care without chemotherapy. Primary outcome was overall survival (OS) and secondary outcome was progression-free survival (PFS). We collected data of 208 patients, of which 138 (66.3%) patients received first line chemotherapy with gemcitabine and cisplatin. Median OS of 69 patients in group I, 63 patients in group II and 65 patients in group III was 9.6 months (95%CI = 6.7-12.5), 9.5 months (95%CI = 7.7-11.3) and 7.6 months (95%CI = 5.0-10.2), respectively. Median PFS was 6.0 months (95%CI = 4.4-7.6) in group I and 5.1 months (95%CI = 3.7-6.5) in group II. Toxicity and number of dose reductions (p = .974) were comparable between the two chemotherapy groups. First-line gemcitabine and cisplatin is an effective and safe treatment for patients with unresectable BTC who do not meet the eligibility criteria for the ABC-02 trial. Median OS, PFS and treatment side effects were comparable between the patients who received chemotherapy (group I vs. group II).

Phase 1 trial evaluating cisplatin, gemcitabine, and veliparib in 2 patient cohorts: Germline BRCA mutation carriers and wild-type BRCA pancreatic ductal adenocarcinoma.

PubMed

O'Reilly, Eileen M; Lee, Jonathan W; Lowery, Maeve A; Capanu, Marinela; Stadler, Zsofia K; Moore, Malcolm J; Dhani, Neesha; Kindler, Hedy L; Estrella, Hayley; Maynard, Hannah; Golan, Talia; Segal, Amiel; Salo-Mullen, Erin E; Yu, Kenneth H; Epstein, Andrew S; Segal, Michal; Brenner, Robin; Do, Richard K; Chen, Alice P; Tang, Laura H; Kelsen, David P

2018-04-01

A phase 1 trial was used to evaluate a combination of cisplatin, gemcitabine, and escalating doses of veliparib in patients with untreated advanced pancreatic ductal adenocarcinoma (PDAC) in 2 cohorts: a germline BRCA1/2-mutated (BRCA+) cohort and a wild-type BRCA (BRCA-) cohort. The aims were to determine the safety, dose-limiting toxicities (DLTs), maximum tolerated dose, and recommended phase 2 dose (RP2D) of veliparib combined with cisplatin and gemcitabine and to assess the antitumor efficacy (Response Evaluation Criteria in Solid Tumors, version 1.1) and overall survival. Gemcitabine and cisplatin were dosed at 600 and 25 mg/m 2 , respectively, over 30 minutes on days 3 and 10 of a 21-day cycle. Four dose levels of veliparib were evaluated: 20 (dose level 0), 40 (dose level 1), and 80 mg (dose level 2) given orally twice daily on days 1 to 12 and 80 mg given twice daily on days 1 to 21 (dose level 2A [DL2A]). Seventeen patients were enrolled: 9 BRCA+ patients, 7 BRCA- patients, and 1 patient with an unknown status. DLTs were reached at DL2A (80 mg twice daily on days 1 to 21). Two of the 5 patients in this cohort (40%) experienced grade 4 neutropenia and thrombocytopenia. Two grade 5 events occurred on protocol. The objective response rate in the BRCA+ cohort was 7 of 9 (77.8%). The median overall survival for BRCA+ patients was 23.3 months (95% confidence interval [CI], 3.8-30.2 months). The median overall survival for BRCA- patients was 11 months (95% CI, 1.5-12.1 months). The RP2D of veliparib was 80 mg by mouth twice daily on days 1 to 12 in combination with cisplatin and gemcitabine; the DLT was myelosuppression. Substantial antitumor activity was seen in BRCA+ PDAC. A randomized phase 2 trial is currently evaluating cisplatin and gemcitabine with and without veliparib for BRCA+ PDAC (NCT01585805). Cancer 2018;124:1374-82. © 2018 American Cancer Society. © 2018 American Cancer Society.

Gemcitabine Plus Radiation Therapy for High-Grade Glioma: Long-Term Results of a Phase 1 Dose-Escalation Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Michelle M., E-mail: michekim@med.umich.edu; Camelo-Piragua, Sandra; Schipper, Matthew

Purpose: To evaluate the tolerability and efficacy of gemcitabine plus radiation therapy (RT) in this phase 1 study of patients with newly diagnosed malignant glioma (HGG). Patients and Methods: Between 2004 and 2012, 29 adults with HGG were enrolled. After any extent of resection, RT (60 Gy over 6 weeks) was given concurrent with escalating doses of weekly gemcitabine. Using a time-to-event continual reassessment method, 5 dose levels were evaluated starting at 500 mg/m{sup 2} during the last 2 weeks of RT and advanced stepwise into earlier weeks. The primary objective was to determine the recommended phase 2 dose of gemcitabine plus RT. Secondary objectivesmore » included progression-free survival, overall survival (OS), and long-term toxicity. Results: Median follow-up was 38.1 months (range, 8.9-117.5 months); 24 patients were evaluable for toxicity. After 2005 when standard practice changed, patients with World Health Organization grade 4 tumors were no longer enrolled. Median progression-free survival for 22 patients with grade 3 tumors was 26.0 months (95% confidence interval [CI] 15.6-inestimable), and OS was 48.5 months (95% CI 26.8-inestimable). In 4 IDH mutated, 1p/19q codeleted patients, no failures occurred, with all but 1 alive at time of last follow-up. Seven with IDH mutated, non-codeleted tumors with ATRX loss had intermediate OS of 73.5 months (95% CI 32.8-inestimable). Six nonmutated, non-codeleted patients had a median OS of 26.5 months (95% CI 25.4-inestimable). The recommended phase 2 dose of gemcitabine plus RT was 750 mg/m{sup 2}/wk given the last 4 weeks of RT. Dose reductions were most commonly due to grade 3 neutropenia; no grade 4 or 5 toxicities were seen. Conclusions: Gemcitabine concurrent with RT is well-tolerated and yields promising outcomes, including in patients with adverse molecular features. It is a candidate for further study, particularly for poor-prognosis patient subgroups with HGG.« less

Multilayer Spheroids To Quantify Drug Uptake and Diffusion in 3D

PubMed Central

2015-01-01

There is a need for new quantitative in vitro models of drug uptake and diffusion to help assess drug toxicity/efficacy as well as new more predictive models for drug discovery. We report a three-dimensional (3D) multilayer spheroid model and a new algorithm to quantitatively study uptake and inward diffusion of fluorescent calcein via gap junction intercellular communication (GJIC). When incubated with calcein-AM, a substrate of the efflux transporter P-glycoprotein (Pgp), spheroids from a variety of cell types accumulated calcein over time. Accumulation decreased in spheroids overexpressing Pgp (HEK-MDR) and was increased in the presence of Pgp inhibitors (verapamil, loperamide, cyclosporin A). Inward diffusion of calcein was negligible in spheroids that lacked GJIC (OVCAR-3, SK-OV-3) and was reduced in the presence of an inhibitor of GJIC (carbenoxolone). In addition to inhibiting Pgp, verapamil and loperamide, but not cyclosporin A, inhibited inward diffusion of calcein, suggesting that they also inhibit GJIC. The dose response curves of verapamil’s inhibition of Pgp and GJIC were similar (IC50: 8 μM). The method is amenable to many different cell types and may serve as a quantitative 3D model that more accurately replicates in vivo barriers to drug uptake and diffusion. PMID:24641346

Metabolite pools and carbon flow during C4 photosynthesis in maize: 13CO2 labeling kinetics and cell type fractionation.

PubMed

Arrivault, Stéphanie; Obata, Toshihiro; Szecówka, Marek; Mengin, Virginie; Guenther, Manuela; Hoehne, Melanie; Fernie, Alisdair R; Stitt, Mark

2017-01-01

Worldwide efforts to engineer C 4 photosynthesis into C 3 crops require a deep understanding of how this complex pathway operates. CO 2 is incorporated into four-carbon metabolites in the mesophyll, which move to the bundle sheath where they are decarboxylated to concentrate CO 2 around RuBisCO. We performed dynamic 13 CO 2 labeling in maize to analyze C flow in C 4 photosynthesis. The overall labeling kinetics reflected the topology of C 4 photosynthesis. Analyses of cell-specific labeling patterns after fractionation to enrich bundle sheath and mesophyll cells revealed concentration gradients to drive intercellular diffusion of malate, but not pyruvate, in the major CO 2 -concentrating shuttle. They also revealed intercellular concentration gradients of aspartate, alanine, and phosphenolpyruvate to drive a second phosphoenolpyruvate carboxykinase (PEPCK)-type shuttle, which carries 10-14% of the carbon into the bundle sheath. Gradients also exist to drive intercellular exchange of 3-phosphoglycerate and triose-phosphate. There is rapid carbon exchange between the Calvin-Benson cycle and the CO 2 -concentrating shuttle, equivalent to ~10% of carbon gain. In contrast, very little C leaks from the large pools of metabolites in the C concentration shuttle into respiratory metabolism. We postulate that the presence of multiple shuttles, alongside carbon transfer between them and the Calvin-Benson cycle, confers great flexibility in C 4 photosynthesis. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

The effect of PI3K inhibitor LY294002 and gemcitabine hydrochloride combined with ionizing radiation on the formation of vasculogenic mimicry of Panc-1 cells in vitro and in vivo.

PubMed

Bai, R; Ding, T; Zhao, J; Liu, S; Zhang, L; Lan, X; Yu, Y; Yin, L

2016-01-01

This research's purpose was to explore the existence of vasculogenic mimicry (VM) in both 3-D matrices of Panc-1 cells in vitro and orthotopic Panc-1 xenografts in vivo and to test the hypothesis that PI3K inhibitor LY294002 and gemcitabine hydrochloride would offer clear treatment benefit when integrated into ionizing radiation (IR) therapeutic regimens for treatment of pancreatic cancer. We explored the existence of VM in both 3-D matrices of Panc-1 cells and orthotopic Panc-1 xenografts. We subsequently investigated the activation of the PI3K/MMPs/Ln-5γ2 signaling pathway in response to IR. LY294002 and gemcitabine hydrochloride were then evaluated for their radiosensitizing effect solely and in combination. We found that VM existed in both 3-D matrices of Panc-1 cells in vitro and orthotopic Panc-1 xenografts in vivo. The expressions of p-Akt and MMP- 2 were found to increase in response to IR. LY294002 and gemcitabine hydrochloride combined with IR better inhibited cell migration, VM formation and MMP-2 mRNA expression of Panc-1 cells in vitro, and we also proved that the novel therapeutic regimen better inhibited tumor growth, tumor metastasis and VM formation of orthotopic Panc-1 xenografts by suppressing the PI3K/MMPs/Ln-5γ2 signaling pathway in vivo. Our present study is among the first to prove the VM formation in orthotopic Panc-1 xenografts. Furthermore, our current study is also among the first to provide preliminary evidence for the use of the novel therapeutic regimen LY294002 and gemcitabine hydrochloride combined with IR for treatment of pancreatic cancer.

Gemcitabine Chemotherapy and Single-Fraction Stereotactic Body Radiotherapy for Locally Advanced Pancreatic Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schellenberg, Devin; Goodman, Karyn A.; Lee, Florence

2008-11-01

Purpose: Fractionated radiotherapy and chemotherapy for locally advanced pancreatic cancer achieves only modest local control. This prospective trial evaluated the efficacy of a single fraction of 25 Gy stereotactic body radiotherapy (SBRT) delivered between Cycle 1 and 2 of gemcitabine chemotherapy. Methods and Materials: A total of 16 patients with locally advanced, nonmetastatic, pancreatic adenocarcinoma received gemcitabine with SBRT delivered 2 weeks after completion of the first cycle. Gemcitabine was resumed 2 weeks after SBRT and was continued until progression or dose-limiting toxicity. The gross tumor volume, with a 2-3-mm margin, was treated in a single 25-Gy fraction by Cyberknife.more » Patients were evaluated at 4-6 weeks, 10-12 weeks, and every 3 months after SBRT. Results: All 16 patients completed SBRT. A median of four cycles (range one to nine) of chemotherapy was delivered. Three patients (19%) developed local disease progression at 14, 16, and 21 months after SBRT. The median survival was 11.4 months, with 50% of patients alive at 1 year. Patients with normal carbohydrate antigen (CA)19-9 levels either at diagnosis or after Cyberknife SBRT had longer survival (p <0.01). Acute gastrointestinal toxicity was mild, with 2 cases of Grade 2 (13%) and 1 of Grade 3 (6%) toxicity. Late gastrointestinal toxicity was more common, with five ulcers (Grade 2), one duodenal stenosis (Grade 3), and one duodenal perforation (Grade 4). A trend toward increased duodenal volumes radiated was observed in those experiencing late effects (p = 0.13). Conclusion: SBRT with gemcitabine resulted in comparable survival to conventional chemoradiotherapy and good local control. However, the rate of duodenal ulcer development was significant.« less

A Phase I Study of Hepatic Arterial Infusion of Nab-Paclitaxel in Combination with Intravenous Gemcitabine and Bevacizumab for Patients with Advanced Cancers and Predominant Liver Metastases

PubMed Central

Tsimberidou, Apostolia M.; Ye, Yang; Wheler, Jennifer; Naing, Aung; Hong, David; Nwosu, Uchechi; Hess, Kenneth R.; Wolff, Robert A.

2014-01-01

PURPOSE We conducted a Phase I clinical trial for patients with advanced cancer and predominant liver disease. EXPERIMENTAL DESIGN Patients were treated with HAI nab-paclitaxel (120-210 mg/m2; day 1); intravenous bevacizumab (10 mg/kg; day 1); and intravenous gemcitabine (600-800 mg/m2; days 1 and 8). A conventional “3 + 3” study design was used. RESULTS Fifty patients with advanced cancer and predominant liver metastases were treated (median age, 58 years; 27 women, 23 men; median number of prior therapies, 3 [range, 0-12]). The most common cancers were breast (n=9) and pancreatic (n=9). Overall, 264 cycles were administered (median/patient, 4; range, 1-17). No dose-limiting toxicities were noted during the escalation phase. On dose level 4, 3 patients were unable to receive gemcitabine on day 8 because of severe thrombocytopenia. Dose level 3 was selected as the maximum tolerated dose (HAI nab-paclitaxel 180 mg/m2 and intravenous gemcitabine 800 mg/m2 and bevacizumab 10 mg/kg); Thirty-two patients were treated in the expansion phase. The most common treatment-related toxicities were thrombocytopenia (n=17), neutropenia (n=10), and fatigue (n=12). Of 46 patients evaluable for response, 9 (20%) had a partial response [1] and 9 (20%) had stable disease for {greater than or equal to} 6 months. The median overall survival duration was 7.0 months (95% CI: 4, 22 months) and the median progression-free survival duration was 4.2 months (95% CI: 2.7, 8.6 months). CONCLUSIONS HAI nab-paclitaxel in combination with gemcitabine and bevacizumab was well tolerated and had antitumor activity in selected patients with advanced cancer and liver metastases. PMID:23377373

ALDH1A3, the Major Aldehyde Dehydrogenase Isoform in Human Cholangiocarcinoma Cells, Affects Prognosis and Gemcitabine Resistance in Cholangiocarcinoma Patients.

PubMed

Chen, Ming-Huang; Weng, Jing-Jie; Cheng, Chi-Tung; Wu, Ren-Chin; Huang, Shih-Chiang; Wu, Chiao-En; Chung, Yi-Hsiu; Liu, Chun-Yu; Chang, Mu-Hsin; Chen, Ming-Han; Chiang, Kun-Chun; Yeh, Ta-Sen; Su, Yeu; Yeh, Chun-Nan

2016-08-15

Intrahepatic cholangiocarcinoma is a fatal primary liver cancer resulting from diagnosis at an advanced stage. Understanding the mechanisms of drug resistance and metastasis of cholangiocarcinoma may improve the disease prognosis. Enhanced aldehyde dehydrogenase (ALDH) activity is suggested to be associated with increased drug resistance and the metastasis. This study aims to investigate the roles of the ALDH isoforms in cholangiocarcinoma. Aldefluor assays, RT-PCR, and Western blot analysis were used to identify the major ALDH isoforms contributing to Aldefluor activity in human cholangiocarcinoma cell lines. We manipulated isoform expression in HuCCT1 cells to elucidate the role of ALDH1A3 in the malignant progression of these cells. Finally, we used immunohistochemical staining to evaluate the clinical significance of ALDH1A3 in 77 hepatectomized cholangiocarcinoma patients and an additional 31 patients with advanced cholangiocarcinoma who received gemcitabine-based therapy. ALDH(high) cholangiocarcinoma cells not only migrated faster but were more resistant to gemcitabine. Among the 19 ALDH isoforms studied, ALDH1A3 was found to be the main contributor to Aldefluor activity. In addition, we also found that knockdown of ALDH1A3 expression in HuCCT1 cells markedly reduced not only their sensitivity to gemcitabine, which might be attributed to a decreased expression of ribonucleotide reductase M1, but also their migration. Most importantly, this enzyme was also identified as an independent poor prognostic factor for patients with intrahepatic cholangiocarcinoma, as well as a prognostic biomarker of gemcitabine-treated patients. ALDH1A3 plays an important role in enhancing malignant behavior of cholangiocarcinoma and serves as a new therapeutic target. Clin Cancer Res; 22(16); 4225-35. ©2016 AACR. ©2016 American Association for Cancer Research.

Cisplatin plus gemcitabine versus a cisplatin-based triplet versus nonplatinum sequential doublets in advanced non-small-cell lung cancer: a Spanish Lung Cancer Group phase III randomized trial.

PubMed

Alberola, V; Camps, C; Provencio, M; Isla, D; Rosell, R; Vadell, C; Bover, I; Ruiz-Casado, A; Azagra, P; Jiménez, U; González-Larriba, J L; Diz, P; Cardenal, F; Artal, A; Carrato, A; Morales, S; Sanchez, J J; de las Peñas, R; Felip, E; López-Vivanco, G

2003-09-01

To compare the survival benefit obtained with cisplatin plus gemcitabine, a cisplatin-based triplet, and nonplatinum sequential doublets in advanced non-small-cell lung cancer (NSCLC). Stage IIIB to IV NSCLC patients were randomly assigned to receive cisplatin 100 mg/m2 day 1 plus gemcitabine 1,250 mg/m2 days 1 and 8, every 3 weeks for six cycles (CG); cisplatin 100 mg/m2 day 1 plus gemcitabine 1,000 mg/m2 and vinorelbine 25 mg/m2 days 1 and 8, every 3 weeks for six cycles (CGV); or gemcitabine 1,000 mg/m2 plus vinorelbine 30 mg/m2 days 1 and 8, every 3 weeks for three cycles, followed by vinorelbine 30 mg/m2 days 1 and 8 plus ifosfamide 3 g/m2 day 1, every 3 weeks for three cycles (GV-VI). Five hundred fifty-seven patients were assigned to treatment (182 CG, 188 CGV, 187 GV-VI). Response rates were significantly inferior for the nonplatinum sequential doublet (CG, 42%; CGV, 41%; GV-VI, 27%; CG v GV-VI, P =.003). No differences in median survival or time to progression were observed. Toxicity was higher for the triplet: grade 3 to 4 neutropenia (GC, 32%; CGV, 57%; GV-VI, 27%; P <.05); neutropenic fever (CG, 4%; CGV, 19%; GV-VI, 5%; P <.0001); grade 3 to 4 thrombocytopenia (CG, 19%; CGV, 23%; GV-VI, 3%; P =.0001); and grade 3 to 4 emesis (GC, 22%; GCV, 32%; GV-VI, 6%; P <.0001). On the basis of these results, CG remains a standard regimen for first-line treatment of advanced NSCLC.

Efficacy and safety of sorafenib in combination with gemcitabine in patients with advanced hepatocellular carcinoma: a multicenter, open-label, single-arm phase II study.

PubMed

Srimuninnimit, Vichien; Sriuranpong, Virote; Suwanvecho, Suthida

2014-09-01

Currently, the only standard systemic treatment for advanced hepatocellular carcinoma is sorafenib monotherapy. The study was conducted to assess the efficacy and safety of the novel combination of sorafenib and gemcitabine in the treatment of advanced hepatocellular carcinoma. Between March 2008 and October 2010, patients with advanced pathologically proven hepatocellular carcinoma who had not received previous systemic therapy and had Child-Pugh liver function class A or B received sorafenib plus gemcitabine. Treatment included 4-week cycle of gemcitabine (1000 mg/m(2) days 1, 8, 15) to the maximum of six cycles together with sorafenib (400 mg twice daily). Patient continued sorafenib until disease progression or withdrawal from other reasons. The primary end point is progression-free survival. Forty-five patients were enrolled in this study. The median progression-free survival was 3.7 months (95% CI 3.5-3.8). The overall response rate was 4% with no complete responses and the disease control rate was 66%. The median overall survival (OS) was 11.6 months (95% CI 7.4-15.9). The median time to progression was 3.6 months (95% CI 3.4-3.7). The most frequently reported grade 3/4 treatment-related adverse events included thrombocytopenia 33%, neutropenia 16% and hand-foot skin reaction 13%. The study regimen was well tolerated. The combination of sorafenib and gemcitabine in advanced hepatocellular carcinoma is generally well tolerated and has modest clinical efficacy. The median OS is up to 1 year. However, well-designed randomized controlled trials with a sorafenib alone comparator arm are needed to confirm this finding. © 2014 Wiley Publishing Asia Pty Ltd.

Optimization for the blockade of epidermal growth factor receptor signaling for therapy of human pancreatic carcinoma.

PubMed

Solorzano, C C; Baker, C H; Tsan, R; Traxler, P; Cohen, P; Buchdunger, E; Killion, J J; Fidler, I J

2001-08-01

We determined the optimal administration schedule of a novel epidermal growth factor receptor (EGFR) protein tyrosine kinase inhibitor (PKI), PKI 166 (4-(R)-phenethylamino-6-(hydroxyl)phenyl-7H-pyrrolo[2.3-d]-pyrimidine), alone or in combination with gemcitabine (administered i.p.) for therapy of L3.6pl human pancreatic carcinoma growing in the pancreas of nude mice. Seven days after orthotopic implantation of L3.6pl cells, the mice received daily oral doses of PKI 166. PKI 166 therapy significantly inhibited phosphorylation of the EGFR without affecting EGFR expression. EGFR phosphorylation was restored 72 h after cessation of therapy. Seven days after orthotopic injection of L3.6pl cells, groups of mice received daily or thrice weekly oral doses of PKI 166 alone or in combination with gemcitabine. Treatment with PKI 166 (daily), PKI 166 (3 times/week), or gemcitabine alone produced a 72%, 69%, or 70% reduction in the volume of pancreatic tumors in mice, respectively. Daily oral PKI 166 or thrice weekly oral PKI 166 in combination with injected gemcitabine produced 97% and 95% decreases in volume of pancreatic cancers and significant inhibition of lymph node and liver metastasis. Daily oral PKI 166 produced a 20% decrease in body weight, whereas treatment 3 times/week did not. Decreased microvessel density, decreased proliferating cell nuclear antigen staining, and increased tumor cell and endothelial cell apoptosis correlated with therapeutic success. Collectively, our results demonstrate that three weekly oral administrations of an EGFR tyrosine kinase inhibitor in combination with gemcitabine are sufficient to significantly inhibit primary and metastatic human pancreatic carcinoma.

Up-regulation of miR-200 and let-7 by natural agents leads to the reversal of epithelial-mesenchymal transition in gemcitabine-resistant pancreatic cancer cells

PubMed Central

Li, Yiwei; VandenBoom, Timothy G.; Kong, Dejuan; Wang, Zhiwei; Ali, Shadan; Philip, Philip A.; Sarkar, Fazlul H.

2009-01-01

Pancreatic cancer (PC) is the fourth most common cause of cancer death in the United States and the aggressiveness of PC is in part due to its intrinsic and extrinsic drug resistance characteristics, which is also associated with the acquisition of epithelial-to-mesenchymal transition (EMT). Emerging evidence also suggest that the processes of EMT is regulated by the expression status of many microRNAs (miRNAs), which are believed to function as key regulators of various biological and pathological processes during tumor development and progression. In the present study, we compared the expression of miRNAs between gemcitabine-sensitive and gemcitabine-resistant PC cells, and investigated whether the treatment of cells with “natural agents” [3,3′-diinodolylmethane (DIM) or isoflavone] could affect the expression of miRNAs. We found that the expression of miR-200b, miR-200c, let-7b, let-7c, let-7d, and let-7e was significantly down-regulated in gemcitabine-resistant cells that showed EMT characteristics such as elongated fibroblastoid morphology, lower expression of epithelial marker E-cadherin, and higher expression of mesenchymal markers such as vimentin and ZEB1. Moreover, we found that re-expression of miR-200 by transfection studies or treatment of gemcitabine-resistant cells with either DIM or isoflavone resulted in the down-regulation of ZEB1, slug, and vimentin, which was consistent with morphological reversal of EMT phenotype leading to epithelial morphology. These results provide experimental evidence, for the first time, that DIM and isoflavone could function as miRNA regulators leading to the reversal of EMT phenotype, which is likely to be important for designing novel therapies for PC. PMID:19654291

Gemcitabine and Nucleos(t)ide Synthesis Inhibitors Are Broad-Spectrum Antiviral Drugs that Activate Innate Immunity.

PubMed

Shin, Hye Jin; Kim, Chonsaeng; Cho, Sungchan

2018-04-20

Nucleoside analogs have been frequently identified as antiviral agents. In recent years, gemcitabine, a cytidine analog in clinical use for the treatment of many solid tumors, was also shown to have antiviral activity against a broad range of viruses. Nucleoside analogs generally interfere with cellular nucleos(t)ide synthesis pathways, resulting in the depletion or imbalance of (d)NTP pools. Intriguingly, a few recent reports have shown that some nucleoside analogs, including gemcitabine, activated innate immunity, inducing the expression of interferon-stimulated genes, through nucleos(t)ide synthesis inhibition. The precise crosstalk between these two independent processes remains to be determined. Nonetheless, we summarize the current knowledge of nucleos(t)ide synthesis inhibition-related innate immunity and propose it as a newly emerging antiviral mechanism of nucleoside analogs.

Excess Diffuse Light Absorption in Upper Mesophyll Limits CO2 Drawdown and Depresses Photosynthesis1[OPEN

PubMed Central

Gilbert, Matthew E.; McElrone, Andrew J.

2017-01-01

In agricultural and natural systems, diffuse light can enhance plant primary productivity due to deeper penetration into and greater irradiance of the entire canopy. However, for individual sun-grown leaves from three species, photosynthesis is actually less efficient under diffuse compared with direct light. Despite its potential impact on canopy-level productivity, the mechanism for this leaf-level diffuse light photosynthetic depression effect is unknown. Here, we investigate if the spatial distribution of light absorption relative to electron transport capacity in sun- and shade-grown sunflower (Helianthus annuus) leaves underlies its previously observed diffuse light photosynthetic depression. Using a new one-dimensional porous medium finite element gas-exchange model parameterized with light absorption profiles, we found that weaker penetration of diffuse versus direct light into the mesophyll of sun-grown sunflower leaves led to a more heterogenous saturation of electron transport capacity and lowered its CO2 concentration drawdown capacity in the intercellular airspace and chloroplast stroma. This decoupling of light availability from photosynthetic capacity under diffuse light is sufficient to generate an 11% decline in photosynthesis in sun-grown but not shade-grown leaves, primarily because thin shade-grown leaves similarly distribute diffuse and direct light throughout the mesophyll. Finally, we illustrate how diffuse light photosynthetic depression could overcome enhancement in canopies with low light extinction coefficients and/or leaf area, pointing toward a novel direction for future research. PMID:28432257

Excess Diffuse Light Absorption in Upper Mesophyll Limits CO2 Drawdown and Depresses Photosynthesis.

PubMed

Earles, J Mason; Théroux-Rancourt, Guillaume; Gilbert, Matthew E; McElrone, Andrew J; Brodersen, Craig R

2017-06-01

In agricultural and natural systems, diffuse light can enhance plant primary productivity due to deeper penetration into and greater irradiance of the entire canopy. However, for individual sun-grown leaves from three species, photosynthesis is actually less efficient under diffuse compared with direct light. Despite its potential impact on canopy-level productivity, the mechanism for this leaf-level diffuse light photosynthetic depression effect is unknown. Here, we investigate if the spatial distribution of light absorption relative to electron transport capacity in sun- and shade-grown sunflower ( Helianthus annuus ) leaves underlies its previously observed diffuse light photosynthetic depression. Using a new one-dimensional porous medium finite element gas-exchange model parameterized with light absorption profiles, we found that weaker penetration of diffuse versus direct light into the mesophyll of sun-grown sunflower leaves led to a more heterogenous saturation of electron transport capacity and lowered its CO 2 concentration drawdown capacity in the intercellular airspace and chloroplast stroma. This decoupling of light availability from photosynthetic capacity under diffuse light is sufficient to generate an 11% decline in photosynthesis in sun-grown but not shade-grown leaves, primarily because thin shade-grown leaves similarly distribute diffuse and direct light throughout the mesophyll. Finally, we illustrate how diffuse light photosynthetic depression could overcome enhancement in canopies with low light extinction coefficients and/or leaf area, pointing toward a novel direction for future research. © 2017 American Society of Plant Biologists. All Rights Reserved.

Overexpression of karyopherin-α2 in cholangiocarcinoma correlates with poor prognosis and gemcitabine sensitivity via nuclear translocation of DNA repair proteins

PubMed Central

Tsukagoshi, Mariko; Araki, Kenichiro; Yokobori, Takehiko; Altan, Bolag; Suzuki, Hideki; Kubo, Norio; Watanabe, Akira; Ishii, Norihiro; Hosouchi, Yasuo; Nishiyama, Masahiko; Shirabe, Ken; Kuwano, Hiroyuki

2017-01-01

Cholangiocarcinoma is a highly malignant tumor, and the development of new therapeutic strategies is critical. Karyopherin-α2 (KPNA2) functions as an adaptor that mediates nucleocytoplasmic transport. Specifically, KPNA2 transports one of the important DNA repair machineries, the MRE11-RAD50-NBS1 (MRN) complex, to the nucleus. In this study, we clarified the significance of KPNA2 in cholangiocarcinoma. KPNA2 expression evaluated by immunohistochemical analysis was common in malignant tissue but rare in adjacent noncancerous tissues. KPNA2 overexpression was significantly correlated with poor prognosis and was an independent prognostic factor after surgery. In patients with cholangiocarcinoma who received gemcitabine after surgery, KPNA2 overexpression tended to be a prognostic indicator of poor overall survival. In KPNA2-depleted cholangiocarcinoma cells, proliferation was significantly decreased and gemcitabine sensitivity was enhanced in vitro and in vivo. Expression of KPNA2 and the MRN complex displayed colocalization in the nucleus. In addition, nuclear localization of the MRN complex was regulated by KPNA2 in vitro. These results suggest that KPNA2 expression may be a useful prognostic and predictive marker of gemcitabine sensitivity and survival. The regulation of KPNA2 expression may be a new therapeutic strategy for cholangiocarcinoma. PMID:28178675

Overexpression of karyopherin-α2 in cholangiocarcinoma correlates with poor prognosis and gemcitabine sensitivity via nuclear translocation of DNA repair proteins.

PubMed

Tsukagoshi, Mariko; Araki, Kenichiro; Yokobori, Takehiko; Altan, Bolag; Suzuki, Hideki; Kubo, Norio; Watanabe, Akira; Ishii, Norihiro; Hosouchi, Yasuo; Nishiyama, Masahiko; Shirabe, Ken; Kuwano, Hiroyuki

2017-06-27

Cholangiocarcinoma is a highly malignant tumor, and the development of new therapeutic strategies is critical. Karyopherin-α2 (KPNA2) functions as an adaptor that mediates nucleocytoplasmic transport. Specifically, KPNA2 transports one of the important DNA repair machineries, the MRE11-RAD50-NBS1 (MRN) complex, to the nucleus. In this study, we clarified the significance of KPNA2 in cholangiocarcinoma. KPNA2 expression evaluated by immunohistochemical analysis was common in malignant tissue but rare in adjacent noncancerous tissues. KPNA2 overexpression was significantly correlated with poor prognosis and was an independent prognostic factor after surgery. In patients with cholangiocarcinoma who received gemcitabine after surgery, KPNA2 overexpression tended to be a prognostic indicator of poor overall survival. In KPNA2-depleted cholangiocarcinoma cells, proliferation was significantly decreased and gemcitabine sensitivity was enhanced in vitro and in vivo. Expression of KPNA2 and the MRN complex displayed colocalization in the nucleus. In addition, nuclear localization of the MRN complex was regulated by KPNA2 in vitro. These results suggest that KPNA2 expression may be a useful prognostic and predictive marker of gemcitabine sensitivity and survival. The regulation of KPNA2 expression may be a new therapeutic strategy for cholangiocarcinoma.

Modulation of chemotherapy-induced cytotoxicity in SH-SY5Y neuroblastoma cells by caffeine and chlorogenic acid.

PubMed

Hall, Susan; Anoopkumar-Dukie, Shailendra; Grant, Gary D; Desbrow, Ben; Lai, Richard; Arora, Devinder; Hong, Yinna

2017-06-01

Chemotherapy is an important treatment modality for malignancy but is limited by significant toxicity and it susceptibility to numerous drug interactions. While the interacting effects with medications are well known, there is limited evidence on the interaction with commonly consumed food and natural products. The aim of this study was to evaluate the bioactive constituents of coffee (caffeine and chlorogenic acid) on the cytotoxicity of doxorubicin, gemcitabine, and paclitaxel in vitro. Pretreatment with caffeine (100 nM and 10 μM) sensitized SH-SY5Y cells to doxorubicin-induced toxicity and increased apoptosis and sensitized PC3 cells to gemcitabine-induced toxicity. Pretreatment with 10 μM caffeine decreased total cell reactive oxygen species (ROS) production but increased mitochondrial ROS production. In contrast, caffeine (10 nM and 10 μM) protected cells against gemcitabine-induced toxicity and apoptosis. Similarly, 1 μM and 10 μM caffeine protected cells against paclitaxel-induced toxicity and mitochondrial ROS production. Chlorogenic acid had no effect on chemotherapy-induced toxicity in SH-SY5Y cells. In conclusion, this study provides preliminary evidence that caffeine, not chlorogenic acid, modulates the cytotoxicity of doxorubicin, gemcitabine, and paclitaxel in SH-SY5Y cells via different mechanisms.

Successful pregnancy after mucinous cystic neoplasm with invasive carcinoma of the pancreas in a patient with polycystic ovarian syndrome: a case report.

PubMed

Holloman, Conisha; Carlan, S J; Sundharkrishnan, Lohini; Guzman, Angela; Madruga, Mario

2017-07-11

The incidence of invasive cancer within a mucinous cystic neoplasm of the pancreas varies between 6 and 36%. Polycystic ovarian syndrome is a disorder characterized by hyperandrogenism and anovulatory infertility. One surgical treatment that can restore endocrine balance and ovulation in polycystic ovarian syndrome is partial ovarian destruction. Successful pregnancies following preconception pancreaticoduodenectomies (Whipple procedures) and chemoradiation to treat pancreatic neoplasms have been reported rarely but none were diagnosed with pre-cancer polycystic ovarian syndrome-associated infertility. Gemcitabine is an antimetabolite drug used for the treatment of pancreatic cancer that can have profound detrimental effects on oogenesis and ovarian function. Whether the ovarian destructive property of gemcitabine could act as a method to restore ovulation potential in polycystic ovarian syndrome is unknown. A 40-year-old white American woman with a history of pancreatic cancer treatment with a Whipple procedure and chemoradiation with gemcitabine had a successful pregnancy after years of pre-cancerous anovulatory infertility and polycystic ovarian syndrome. She received no fertility agents and delivered full term via a spontaneous vaginal delivery with no pregnancy complications. Gemcitabine treatment for pancreatic cancer may result in resumption of ovulation in women with polycystic ovarian syndrome and these women should be counseled accordingly.

Phase I trial of S-1 every other day in combination with gemcitabine/cisplatin for inoperable biliary tract cancer.

PubMed

Uwagawa, Tadashi; Sakamoto, Taro; Abe, Kyohei; Okui, Norimitsu; Hata, Daigo; Shiba, Hiroaki; Futagawa, Yasuro; Aiba, Keisuke; Yanaga, Katsuhiko

2015-01-01

To date, gemcitabine-based or fluoropyrimidine-based regimens are recommended for unresectable advanced biliary tract cancer. Then, we conducted a phase I study of gemcitabine/cisplatin and S-1 that is an oral fluoropyrimidine. The aim of this study was to determine the dose-limiting toxicity (DLT), maximum-tolerated dose, and a recommended phase II dose of S-1. Response was assessed as a secondary endpoint. Patients who have been diagnosed with unresectable or postoperative recurrent biliary tract cancer received cisplatin (25 mg/m² i.v. for 120 min) followed by gemcitabine (1,000 mg/m² i.v. for 30 min) on days 1 and 8, and oral S-1 on alternate days; this regimen was repeated at 21-day intervals. A standard '3 + 3' phase I dose-escalation design was adopted. This study was registered with University hospital Medical Information Network (UMIN) Center in Japan, number UMIN000008415. Twelve patients were evaluable in this study. No patients developed DLTs. Recommended dose of S-1 was 80 (<1.25 m²), 100 (1.25 ≤ 1.5 m²), and 120 mg (1.5 m²≥) per day. One patient could achieve conversion to curative surgery. This phase I study was performed safely and demonstrated encouraging response.

Involvement of CYP4F2 in the Metabolism of a Novel Monophosphate Ester Prodrug of Gemcitabine and Its Interaction Potential In Vitro.

PubMed

Wang, Yedong; Li, Yuan; Lu, Jia; Qi, Huixin; Cheng, Isabel; Zhang, Hongjian

2018-05-16

Compound- 3 is an oral monophosphate prodrug of gemcitabine. Previous data showed that Compound- 3 was more potent than gemcitabine and it was orally active in a tumor xenograft model. In the present study, the metabolism of Compound- 3 was investigated in several well-known in vitro matrices. While relatively stable in human and rat plasma, Compound- 3 demonstrated noticeable metabolism in liver and intestinal microsomes in the presence of NADPH and human hepatocytes. Compound- 3 could also be hydrolyzed by alkaline phosphatase, leading to gemcitabine formation. Metabolite identification using accurate mass- and information-based scan techniques revealed that Compound- 3 was subjected to sequential metabolism, forming alcohol, aldehyde and carboxylic acid metabolites, respectively. Results from reaction phenotyping studies indicated that cytochrome P450 4F2 (CYP4F2) was a key CYP isozyme involved in Compound- 3 metabolism. Interaction assays suggested that CYP4F2 activity could be inhibited by Compound- 3 or an antiparasitic prodrug pafuramidine. Because CYP4F2 is a key CYP isozyme involved in the metabolism of eicosanoids and therapeutic drugs, clinical relevance of drug-drug interactions mediated via CYP4F2 inhibition warrants further investigation.

Study of immunoglobulins in pleura and pleural effusions.

PubMed Central

Telvi, L; Jaubert, F; Eyquem, A; Andreux, J P; Labrousse, F; Chrétien, J

1979-01-01

The protein concentration of 35 pleural effusions was compared with that in the serum. The ratio of the pleural and serum concentration of albumin, IgG, IgA, and IgM is always below unity and appears to have no diagnostic value. However, the ratio of the concentration of these proteins was inversely related to their molecular weight. The underlying mechanism in malignant and inflammatory effusions appear similar and is in keeping with a diffusion process. Immunofluorescent staining of the pleura suggests the intercellular passage of the proteins through the mesothelial barrier. Images PMID:384578

[The possibility of local control of cancer by neoadjuvant chemoradiation therapy with gemcitabine and surgical resection for advanced cholangiocarcinoma].

PubMed

Nakagawa, Kei; Katayose, Yu; Rikiyama, Toshiki; Okaue, Adoru; Unno, Michiaki

2009-11-01

Surgical resection is the gold standard of treatment for cholangiocarcinoma. However, there are also many recurrences after operation, because of the anatomical background and the tendency of invasion. We thought that eliminating the remnant of the cancer could yield a better prognosis. Therefore, an introduction of the neoadjuvant chemoradiation therapy with gemcitabine and surgical resection for advanced cholangiocarcinoma patient (NACRAC) was planned. The safety of NACRAC was confirmed by a pilot study. The recommended dose of gemcitabine (600 mg/m2) was determined by a phase I study. A phase II study is now being performed for evaluating the effectiveness and safety. NACRAC may control the frontal part of the tumor with difficult distinctions made by MDCT, and abolishing the cancer remnant is expected. The possibility of extended prognosis by NACRAC can be considered.

Conjugation of squalene to gemcitabine as unique approach exploiting endogenous lipoproteins for drug delivery

NASA Astrophysics Data System (ADS)

Sobot, Dunja; Mura, Simona; Yesylevskyy, Semen O.; Dalbin, Laura; Cayre, Fanny; Bort, Guillaume; Mougin, Julie; Desmaële, Didier; Lepetre-Mouelhi, Sinda; Pieters, Grégory; Andreiuk, Bohdan; Klymchenko, Andrey S.; Paul, Jean-Louis; Ramseyer, Christophe; Couvreur, Patrick

2017-05-01

Once introduced in the organism, the interaction of nanoparticles with various biomolecules strongly impacts their fate. Here we show that nanoparticles made of the squalene derivative of gemcitabine (SQGem) interact with lipoproteins (LPs), indirectly enabling the targeting of cancer cells with high LP receptors expression. In vitro and in vivo experiments reveal preeminent affinity of the squalene-gemcitabine bioconjugates towards LP particles with the highest cholesterol content and in silico simulations further display their incorporation into the hydrophobic core of LPs. To the best of our knowledge, the use of squalene to induce drug insertion into LPs for indirect cancer cell targeting is a novel concept in drug delivery. Interestingly, not only SQGem but also other squalene derivatives interact similarly with lipoproteins while such interaction is not observed with liposomes. The conjugation to squalene represents a versatile platform that would enable efficient drug delivery by simply exploiting endogenous lipoproteins.

[Effect of anti-cancer drugs on the expression of BIC/miR-155 in human pancreatic cancer PANC-1 cells].

PubMed

Xia, Qi-sheng; Ishigaki, Yasuhito; Sun, Li; Chen, Rui; Motoo, Yoshiharu

2010-01-12

To investigate the effect of anti-cancer drugs on the expression of B-cell integration cluster (BIC) RNA/miRNA-155 in human pancreatic cancer PANC-1 cells. PANC-1 cells were treated with different concentrations of anti-cancer drugs. Total RNA of the treated cells were harvested and the expression levels of BIC RNA and mature miR-155 were quantified by using Taqman FAM/MGB probes on a real-time PCR system. Relative quantification was carried out using the DeltaDeltaCt method. A PI3K-related kinases inhibitor was used to determine whether these kinases were involved in the regulation of BIC RNA. The expression of BIC RNA was strongly induced by anti-cancer drugs. When PANC-1 cells were treated by gemcitabine with concentrations of 1.0, 2.5, 5.0, 10.0 mg/L for 48 h and 72 h, the level of BIC RNA (48 h: 37.1 +/- 4.1, 29.0 +/- 5.7, 21.0 +/- 7.6, 40.4 +/- 9.0, 72 h: 27.7 +/- 3.1, 43.1 +/- 1.2, 31.8 +/- 5.4, 23.1 +/- 1.4) were significantly higher than that of the control (48 h: 1.6 +/- 1.1, 72 h: 1.0 +/- 0.1, all P < 0.05). 5-FU (10 mg/L, 48 h) and bleomycin (100 mg/L, 48 h) also induced BIC RNA up-regulation (5.2 +/- 1.1 vs 1.7 +/- 0.7, 11.5 +/- 0.7 vs 1.7 +/- 0.7, both P < 0.05). When PANC-1 cells treated with 1.0, 2.5, 5.0, 10.0 mg/L gemcitabine for 72 h, the level of miR-155 (2.21 +/- 0.40, 1.86 +/- 0.03, 2.47 +/- 0.04, 3.24 +/- 0.05) also higher than that of the control (1.11 +/- 0.09, P < 0.05), while no change was observed when the cells only treated for 48 h. Further study showed gemcitabine-induced BIC RNA up-regulation was inhibited by wortmannin, a specific PI3K inhibitor, the expression levels of BIC RNA of 1 micromol/L wortmannin + 5 mg/L gemcitabine group and 10 micromol/L wortmannin + 5 mg/L gemcitabine group were 5.34 +/- 1.11 and 1.26 +/- 0.07, lower than that of 5 mg/L gemcitabine group (11.82 +/- 3.11, P < 0.05). BIC RNA is strongly induced by anti-cancer drugs in PANC-1 cells and the levels of miR-155 also slightly increase. PI3K pathway is involved in gemcitabine-induced BIC RNA up-regulation.

Budget impact model of adding erlotinib to a regimen of gemcitabine for the treatment of locally advanced, nonresectable or metastatic pancreatic cancer.

PubMed

Danese, Mark D; Reyes, Carolina; Northridge, Kelly; Lubeck, Deborah; Lin, Chin-Yu; O'Connor, Paula

2008-04-01

The aim of this study was to determine the budget impact of adding erlotinib to a US health plan insurer's formulary as a combination therapy with gemcitabine for the treatment of nonresectable pancreatic cancer. An Excel-based budget impact model was developed to evaluate the costs for National Comprehensive Cancer Network guideline-recommended treatment options for patients with locally advanced, nonresectable or metastatic pancreatic cancer from the perspective of a US managed care plan. The model compared treatment with gemcitabine alone and in combination with erlotinib, including the costs of treatment, adverse events (AEs), and administration. Inputs for the model were derived from the Surveillance, Epidemiology and End Results Cancer Registry, clinical trials, and publicly available sources and were varied in sensitivity analyses to identify influential inputs. The model addressed first-line use in a single indication and assumed that the proportion of patients aged >or=65 years in a managed care organization was the same as in the general population. The model did not account for patient copayments for oral medications, a factor that could lower a plan's overall cost further than estimated herein. For a hypothetical managed care plan with 500,000 members, the model estimated 43 newly diagnosed pancreatic cancer cases each year, of which 56% (n=24) would be treated with gemcitabine as first-line therapy. Assuming that erlotinib were added to the treatment regimen in 40% (n=10) of gemcitabine-treated patients for 15.7 weeks of therapy per patient, the expected 1-year cost in 2006 dollars would be US $466,700 compared with $346,700 had all patients been treated with gemcitabine alone. Administration costs accounted for 10% to 12% of total costs, while AE management costs made up 14% to 16% of total costs. These estimates corresponded to an incremental cost of $120,000, or $0.020 per member per month (PMPM). The results were relatively insensitive to drug costs, drug administration costs, and costs of treatment of AEs based on sensitivity analyses. In this analysis of the budget impact of adding to the health plan formulary erlotinib to a regimen of gemcitabine as first-line treatment of locally advanced, nonresectable or metastatic pancreatic cancer in the United States, the budget impact was $0.020 PMPM. The relatively low incidence of pancreatic cancer and the assumption of treating only 23% of these patients with erlotinib were likely the principal reasons for the low budgetary impact of erlotinib. In this model and using these reasonable assumptions, the results suggested that the incremental cost impact on a PMPM basis may be small.

Nab-paclitaxel plus either gemcitabine or simplified leucovorin and fluorouracil as first-line therapy for metastatic pancreatic adenocarcinoma (AFUGEM GERCOR): a non-comparative, multicentre, open-label, randomised phase 2 trial.

PubMed

Bachet, Jean-Baptiste; Hammel, Pascal; Desramé, Jérôme; Meurisse, Aurélia; Chibaudel, Benoist; André, Thierry; Debourdeau, Philippe; Dauba, Jérome; Lecomte, Thierry; Seitz, Jean-François; Tournigand, Christophe; Aparicio, Thomas; Meyer, Véronique Guerin; Taieb, Julien; Volet, Julien; Monier, Amandine; Bonnetain, Franck; Louvet, Christophe

2017-05-01

Nab-paclitaxel plus gemcitabine has become a standard treatment regimen in patients with metastatic pancreatic adenocarcinoma; however, retrospective data suggest that gemcitabine might be inefficient in 50-60% of patients and thus not an optimum regimen in combination with nab-paclitaxel. We did a phase 2 trial to assess the activity and safety of a new regimen of nab-paclitaxel plus simplified leucovorin and fluorouracil. We did a non-comparative, multicentre, open-label, randomised phase 2 trial in 15 hospitals and institutions in France. Eligible participants were previously untreated patients with metastatic pancreatic adenocarcinoma (previous adjuvant chemotherapy after curative intent resection was allowed if the interval between the end of chemotherapy and relapse was more than 12 months). Patients had to have at least one measurable lesion assessed by CT scan or MRI and an Eastern Cooperative Oncology Group (ECOG) performance status of 2 or less. We randomly assigned participants (1:2) centrally to 28-day cycles of either gemcitabine plus nab-paclitaxel or simplified leucovorin and fluorouracil plus nab-paclitaxel. The randomisation was by minimisation, stratified by centre and ECOG performance status. Drugs were administered in each cycle as follows: nab-paclitaxel (125 mg/m 2 ) and gemcitabine (1000 mg/m 2 ) as 30-min intravenous infusions on days 1, 8, and 15; leucovorin (400 mg/m 2 ) as a 120-min intravenous infusion on days 1 and 15; and fluorouracil (400 mg/m 2 ) as a 5-min bolus intravenous infusion followed by a 46-h continuous intravenous infusion of 2400 mg/m 2 on days 1 and 15. Patients continued treatment until unacceptable toxicity, disease progression, or patient withdrawal. The primary endpoint was progression-free survival at 4 months in the first 72 assessable patients in the leucovorin and fluorouracil group, with a target of 50% for the regimen to be deemed sufficiently active to warrant further study. We did the primary analysis on the modified intention-to-treat (ITT) population, defined as all randomly assigned and assessable patients regardless of their eligibility and received treatments. This trial is registered at ClinicalTrials.gov, number NCT01964534. The trial has ended and we report the final analysis here. Between Dec 12, 2013, and Oct 31, 2014, we randomly assigned 114 patients to treatment: 75 patients to the leucovorin and fluorouracil group and 39 to the gemcitabine group. One patient in the leucovorin and fluorouracil group did not have a 4-month assessment, and was thus excluded from the modified ITT analysis. Median follow-up was 13·1 months (95% CI 12·5-14·1). At 4 months, 40 (56%, 90% CI 45-66) of 72 patients in the leucovorin and fluorouracil group were alive and free from disease progression (21 [54%, 40-68] of 39 patients in the gemcitabine group were also alive and progression-free at 4 months). Grade 3-4 adverse events occurred in 33 (87%) of 38 patients in the gemcitabine group and in 56 (77%) of 73 patients in the leucovorin and fluorouracil group, with different toxicity profiles. The most common grade 3-4 adverse events in the leucovorin and fluorouracil group were neutropenia without fever (17 [23%]), fatigue (16 [22%]), paraesthesia (14 [19%]), diarrhoea (nine [12%]), and mucositis (seven [10%]); in the gemcitabine group they were neutropenia without fever (12 [32%]), thrombocytopenia (seven [18%]), fatigue (eight [21%]), anaemia (five [13%]), increased alanine aminotransferase and aspartate aminotransferase concentrations (five [13%] for both), and paraesthesia (four [11%]). Two participants died; one in the leucovorin and fluorouracil group from septic shock, and one in the gemcitabine group from diabetes compensation with acidosis; these deaths were deemed to be not related to treatment. Treatment-related serious adverse events occurred in 28 (38%) of 73 patients in the leucovorin and fluorouracil group and in 14 (37%) of 38 in the gemcitabine group. Nab-paclitaxel plus simplified leucovorin and fluorouracil fulfilled the primary endpoint in that more than the required 50% of our study population were progression-free at 4 months, with a tolerable toxicity profile. This regimen thus deserves further assessment in a phase 3 trial. GERCOR (Groupe Coopérateur Multidisciplinaire en Oncologie) and Celgene through grants to GERCOR. Copyright © 2017 Elsevier Ltd. All rights reserved.

Potential Combinational Anti-Cancer Therapy in Non-Small Cell Lung Cancer with Traditional Chinese Medicine Sun-Bai-Pi Extract and Cisplatin

PubMed Central

Wang, Jhih-Syuan; Chung, Meng-Chi; Chang, Jing-Fen; Chao, Ming-Wei

2016-01-01

Traditional lung cancer treatments involve chemical or radiation therapies after surgical tumor removal; however, these procedures often kill normal cells as well. Recent studies indicate that chemotherapies, when combined with Traditional Chinese Medicines, may offer a new way to treat cancer. In vitro tests measuring the induction of autophagy and/or apoptosis were used to examine the cytotoxicity of SBPE, commonly used for lung inflammation on A549 cell line. The results indicated that intercellular levels of p62 and Atg12 were increased, LC3-I was cleaved into LC3-II, and autophagy was induced with SBPE only. After 24 hours, the apoptotic mechanism was induced. If the Cisplatin was added after cells reached the autophagy state, we observed synergistic effects of the two could achieve sufficient death of lung cancer cells. Therefore, the Cisplatin dosage used to induce apoptosis could be reduced by half, and the amount of time needed to achieve the inhibitory concentration of 50% was also half that of the original. In addition to inducing autophagy within a shortened period of time, the SBPE and chemotherapy drug combination therapy was able to achieve the objective of rapid low-dosage cancer cell elimination. Besides, SBPE was applied with Gemcitabine or Paclitaxel, and found that the combination treatment indeed achieve improved lung cancer cell killing effects. However, SBPE may also be less toxic to normal cells. PMID:27171432

GPRC5A is a potential oncogene in pancreatic ductal adenocarcinoma cells that is upregulated by gemcitabine with help from HuR.

PubMed

Zhou, H; Telonis, A G; Jing, Y; Xia, N L; Biederman, L; Jimbo, M; Blanco, F; Londin, E; Brody, J R; Rigoutsos, I

2016-07-14

GPRC5A is an orphan G-protein coupled receptor with an intriguing dual behavior, acting as an oncogene in some cancers and as a tumor suppressor in other cancers. In the pancreatic cancer context, very little is known about GPRC5A. By analyzing messenger RNA (mRNA) expression data from 675 human cancer cell lines and 10 609 samples from The Cancer Genome Atlas (TCGA) we found that GPRC5A's abundance in pancreatic cancer is highest (cell lines) or second highest (TCGA) among all tissues and cancer types. Further analyses of an independent set of 252 pancreatic normal and cancer samples showed GPRC5A mRNA to be more than twofold upregulated in primary tumor samples compared with normal pancreas (P-value<10(-5)), and even further upregulated in pancreatic cancer metastases to various organs (P-value=0.0021). Immunostaining of 208 cores (103 samples) of a tissue microarray showed generally low expression of GPRC5A protein in normal pancreatic ductal cells; on the other hand, in primary and metastatic samples, GPRC5A protein levels were dramatically increased in pancreatic ductal cells. In vitro studies of multiple pancreatic cancer cell lines showed that an increase in GPRC5A protein levels promoted pancreatic cancer cell growth and migration. Unexpectedly, when we treated pancreatic cancer cell lines with gemcitabine (2',2'-difluorodeoxycytidine), we observed an increase in GPRC5A protein abundance. On the other hand, when we knocked down GPRC5A we sensitized pancreatic cancer cells to gemcitabine. Through further experimentation we showed that the monotonic increase in GPRC5A protein levels that we observe for the first 18 h following gemcitabine treatment results from interactions between GPRC5A's mRNA and the RNA-binding protein HuR, which is an established key mediator of gemcitabine's efficacy in cancer cells. As we discovered, the interaction between GPRC5A and HuR is mediated by at least one HuR-binding site in GPRC5A's mRNA. Our findings indicate that GPRC5A is part of a complex molecular axis that involves gemcitabine and HuR, and, possibly, other genes. Further work is warranted before it can be established unequivocally that GPRC5A is an oncogene in the pancreatic cancer context.

EGFR targeted PLGA nanoparticles using gemcitabine for treatment of pancreatic cancer.

PubMed

Aggarwal, Sahil; Yadav, Sachin; Gupta, Swati

2011-02-01

The present study aimed to prepare and characterize anti EGFR monoclonal antibody (mab) conjugated Gemcitabine loaded PLGA nanoparticles for their selective delivery to pancreatic cells and evaluation of the systems in vitro. It was observed that direct covalent coupling of antibodies to glutaraldehyde activated nanoparticles is an appropriate method to achieve cell-type specific drug carrier systems based on polymeric nanoparticles that have potential to be applied for targeted chemotherapy in EGFR positive cancer.

CHOP plus etoposide and gemcitabine (CHOP-EG) as front-line chemotherapy for patients with peripheral T cell lymphomas.

PubMed

Kim, Jong Gwang; Sohn, Sang Kyun; Chae, Yee Soo; Kim, Dong Hwan; Baek, Jin Ho; Lee, Kyu Bo; Lee, Je-Jung; Chung, Ik-Joo; Kim, Hyeoung-Joon; Yang, Deok-Hwan; Lee, Won-Sik; Joo, Young-Don; Sohn, Chang-Hak

2006-07-01

The present study evaluated the feasibility of CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) plus etoposide and gemcitabine (CHOP-EG) as front-line chemotherapy in patients with peripheral T cell lymphomas (PTCLs). Twenty-six patients with newly diagnosed PTCLs were enrolled into the pilot study. Treatment consisted of classical CHOP plus etoposide 100 mg/m(2) intravenously (i.v.) on day 1 and gemcitabine 600 mg/m(2) i.v. on day 1 in a 3 week interval. Fifteen complete responses (CR, 57.7%) or one unconfirmed complete response (uCR, 3.8%) and four partial responses (PR, 15.4%) were confirmed, giving an overall response rate of 76.9% (95% CI, 58.3-96.3%). Median survival has not yet been reached, while median event free survival was 215 days at a median follow-up duration of 383 days. Estimated overall survival at 1 year was 69.6%. The most severe haematological adverse event was neutropaenia, which occurred with a grade 4 intensity in 14 patients (53.8%). Additionally, febrile neutropaenia was observed in four patients (15.4%). However, there was no treatment-related death. The CHOP-EG regimen was found to be feasible in patients with PTCLs. For further investigation on the role of gemcitabine in the treatment of PTCLs, a more large scale phase II or phase III study is warranted.

Can we customize chemotherapy? Individualizing cytotoxic regimens in advanced non-small-cell lung cancer.

PubMed

Rosell, Rafael; Manegold, Christian; Moran, Teresa; Garrido, Pilar; Blanco, Remei; Lianes, Pilar; Stahel, Rolf; Trigo, Jose Manuel; Wei, Jia; Taron, Miquel

2008-03-01

Metastatic non-small-cell lung cancer remains a fatal disease with a median survival of < 1 year. A critical challenge is to develop predictive markers for customizing platinum-based treatment. The first studies focused on the excision repair cross-complementing 1 (ERCC1) gene in this difficult task. Several layers of evidence indicate that ERCC1 mRNA expression could be a predictive marker for cisplatin alone or in combination with certain drugs such as etoposide, gemcitabine, and 5-fluorouracil but not in combination with antimicrotubule drugs. Several retrospective studies demonstrated an impressive survival advantage for gemcitabine plus cisplatin but not for other combinations in tumors with low ERCC1 expression. A customized phase III ERCC1-based trial met the primary endpoint of improvement in response but not in survival, leading us to hypothesize that docetaxel might not be the most appropriate partner for cisplatin in the presence of low ERCC1 levels or for gemcitabine in the presence of high ERCC1 levels. A phase II study demonstrated the feasibility of combining carboplatin, gemcitabine, docetaxel, and vinorelbine according to ERCC1 and ribonucleotide reductase subunit M1 expression levels. These findings highlight the importance of continual learning, and decision-making strategies for customizing treatment should reflect the limitations of our knowledge. Copyright © 2008 Elsevier Inc. All rights reserved.

Thermosensitive gemcitabine-magnetoliposomes for combined hyperthermia and chemotherapy

NASA Astrophysics Data System (ADS)

Ferreira, Roberta V.; da Mata Martins, Thaís Maria; Goes, Alfredo Miranda; Fabris, José D.; Cavalcante, Luis Carlos D.; Eugenio Fernandez Outon, Luis; Domingues, Rosana Z.

2016-02-01

The combination of magnetic hyperthermia therapy with the controlled release of chemotherapeutic agents in tumors may be an efficient therapeutic with few side effects because the bioavailability, tolerance and amount of the drug can be optimized. Here, we prepared magnetoliposomes consisting of magnetite nanoparticle cores and the anticancer drug gemcitabine encapsulated by a phospholipid bilayer. The potential of these magnetoliposomes for controlled drug release and cancer treatment via hyperthermic behavior was investigated. The magnetic nanoparticle encapsulation efficiency was dependent on the initial amount of magnetite nanoparticles present at the encapsulation stage; the best formulation was 66%. We chose this formulation to characterize the physicochemical properties of the magnetoliposomes and to encapsulate gemcitabine. The mean particle size and distribution were determined by dynamic light scattering (DLS), and the zeta potential was measured. The magnetoliposome formulations all had acceptable characteristics for systemic administration, with a mean size of approximately 150 nm and a polydispersity index <0.2. The magnetoliposomes were stable in aqueous suspension for at least one week, as determined by DLS. Temperature increases due to the dissipation energy of magnetoliposome suspensions subjected to an applied alternating magnetic field (AMF) were measured at different magnetic field intensities, and the values were appropriated for cancer treatments. The drug release profile at 37 °C showed that 17% of the gemcitabine was released after 72 h. Drug release from magnetoliposomes exposed to an AMF for 5 min reached 70%.

Fructose-1,6-bisphosphatase Inhibits ERK Activation and Bypasses Gemcitabine Resistance in Pancreatic Cancer by Blocking IQGAP1–MAPK Interaction

PubMed Central

Jin, Xin; Pan, Yunqian; Wang, Liguo; Ma, Tao; Zhang, Lizhi; Tang, Amy H.; Billadeau, Daniel D.; Wu, Heshui; Huang, Haojie

2017-01-01

Dysregulation of the MAPK pathway correlates with progression of pancreatic ductal adenocarcinoma (PDAC) progression. IQ motif containing GTPase-activating protein 1 (IQGAP1) is a MAPK scaffold that directly regulates the activation of RAF, MEK, and ERK. Fructose-1,6-bisphosphatase (FBP1), a key enzyme in gluconeogenesis, is transcriptionally downregulated in various cancers, including PDAC. Here, we demonstrate that FBP1 acts as a negative modulator of the IQGAP1–MAPK signaling axis in PDAC cells. FBP1 binding to the WW domain of IQGAP1 impeded IQGAP1-dependent ERK1/2 phosphorylation (pERK1/2) in a manner independent of FBP1 enzymatic activity. Conversely, decreased FBP1 expression induced pERK1/2 levels in PDAC cell lines and correlated with increased pERK1/2 levels in patient specimens. Treatment with gemcitabine caused undesirable activation of ERK1/2 in PDAC cells, but cotreatment with the FBP1-derived small peptide inhibitor FBP1 E4 overcame gemcitabine-induced ERK activation, thereby increasing the anticancer efficacy of gemcitabine in PDAC. These findings identify a primary mechanism of resistance of PDAC to standard therapy and suggest that the FBP1–IQGAP1–ERK1/2 signaling axis can be targeted for effective treatment of PDAC. PMID:28720574

Methylenetetrahydrofolate reductase C677T polymorphism predicts response and time to progression to gemcitabine-based chemotherapy for advanced non-small cell lung cancer in a Chinese Han population*

PubMed Central

Hong, Wei; Wang, Kai; Zhang, Yi-ping; Kou, Jun-yan; Hong, Dan; Su, Dan; Mao, Wei-min; Yu, Xin-min; Xie, Fa-jun; Wang, Xiao-jian

2013-01-01

Objective: The aim of this study was to evaluate the association between the methylenetetrahydrofolate reductase (MTHFR) C677T excision repair cross-complementation group 1 (ERCC1) genetic polymorphisms and the clinical efficacy of gemcitabine-based chemotherapy in advanced non-small cell lung cancer (NSCLC). Methods: A total of 135 chemonaive patients with unresectable advanced NSCLC were treated with gemcitabine/platinum regimens. The polymorphisms of MTHFR C677T, ERCC1 C8092A, and ERCC1 C118T were genotyped using the TaqMan methods. Results: The overall response rate was 28.9%. Patients with MTHFR CC genotype had a higher rate of objective response than patients with variant genotype (TT or CT) (41.2% versus 19.1%, P=0.01). Median time to progression (TTP) of patients with MTHFR CC genotype was longer than that of patients with variant genotype (7.6 months versus 5.0 months, P=0.003). No significant associations were obtained between ERCC1 C118T and C8092A polymorphisms and both response and survival. Conclusions: Our data suggest the value of MTHFR C677T polymorphism as a possible predictive marker of response and TTP in advanced NSCLC patients treated with gemcitabine/platinum. PMID:23463763

Systemic gemcitabine combined with intra-arterial low-dose cisplatin and 5-fluorouracil for advanced hepatocellular carcinoma: Seven cases

PubMed Central

Uka, Kiminori; Aikata, Hiroshi; Takaki, Shintaro; Kawaoka, Tomokazu; Saneto, Hiromi; Miki, Daiki; Takahashi, Shoichi; Toyota, Naoyuki; Ito, Katsuhide; Chayama, Kazuaki

2008-01-01

The combination of intra-arterial low-dose cisplatin and 5-fluorouracil (5-FU) is effective against advanced hepatocellular carcinoma (HCC). Systemic gemcitabine chemotherapy seems effective in many cancers. We report the results of combination therapy with systemic gemcitabine, intra-arterial low-dose cisplatin and 5-FU (GEMFP). Seven patients with non-resectable advanced HCC were treated with GEMFP. One course of chemotherapy consisted of daily intra-arterial cisplatin (20 mg/body weight/hour on d 1, 10 mg/body weight per 0.5 h on d 2-5 and 8-12), followed by 5-FU (250 mg/body weight per 5 h on d 1-5 and 8-12) via an injection port. Gemcitabine at 1000 mg/m2 was administered intravenously at 0.5 h on d 1 and 8. The objective response was 57%. The response to GEMFP was as follows: complete response (no patients), partial response (four patients), stable disease (three patients), and progressive disease (no patients). The median survival period was 8 mo (range, 5-55). With regard to the National Cancer Institute Common Toxicity Criteria (NCI-CTC) grade 3 or 4 adverse reactions, seven (100%), seven, six (86%) and one (14%) patients developed leukopenia, neutropenia, thrombocytopenia and anemia, respectively. GEMFP may potentially be effective for non-resectable advanced HCC, but it has severe hematologic toxicity. PMID:18442216

Gemcitabine diphosphate choline is a major metabolite linked to the Kennedy pathway in pancreatic cancer models in vivo.

PubMed

Bapiro, T E; Frese, K K; Courtin, A; Bramhall, J L; Madhu, B; Cook, N; Neesse, A; Griffiths, J R; Tuveson, D A; Jodrell, D I; Richards, F M

2014-07-15

The modest benefits of gemcitabine (dFdC) therapy in patients with pancreatic ductal adenocarcinoma (PDAC) are well documented, with drug delivery and metabolic lability cited as important contributing factors. We have used a mouse model of PDAC: KRAS(G12D); p53(R172H); pdx-Cre (KPC) that recapitulates the human disease to study dFdC intra-tumoural metabolism. LC-MS/MS and NMR were used to measure drug and physiological analytes. Cytotoxicity was assessed by the Sulphorhodamine B assay. In KPC tumour tissue, we identified a new, Kennedy pathway-linked dFdC metabolite (gemcitabine diphosphate choline (GdPC)) present at equimolar amounts to its precursor, the accepted active metabolite gemcitabine triphosphate (dFdCTP). Utilising additional subcutaneous PDAC tumour models, we demonstrated an inverse correlation between GdPC/dFdCTP ratios and cytidine triphosphate (CTP). In tumour homogenates in vitro, CTP inhibited GdPC formation from dFdCTP, indicating competition between CTP and dFdCTP for CTP:phosphocholine cytidylyltransferase (CCT). As the structure of GdPC precludes entry into cells, potential cytotoxicity was assessed by stimulating CCT activity using linoleate in KPC cells in vitro, leading to increased GdPC concentration and synergistic growth inhibition after dFdC addition. GdPC is an important element of the intra-tumoural dFdC metabolic pathway in vivo.

A nu-space for image correlation spectroscopy: characterization and application to measure protein transport in live cells

NASA Astrophysics Data System (ADS)

Potvin-Trottier, Laurent; Chen, Lingfeng; Horwitz, Alan Rick; Wiseman, Paul W.

2013-08-01

We introduce a new generalized theoretical framework for image correlation spectroscopy (ICS). Using this framework, we extend the ICS method in time-frequency (ν, nu) space to map molecular flow of fluorescently tagged proteins in individual living cells. Even in the presence of a dominant immobile population of fluorescent molecules, nu-space ICS (nICS) provides an unbiased velocity measurement, as well as the diffusion coefficient of the flow, without requiring filtering. We also develop and characterize a tunable frequency-filter for spatio-temporal ICS (STICS) that allows quantification of the density, the diffusion coefficient and the velocity of biased diffusion. We show that the techniques are accurate over a wide range of parameter space in computer simulation. We then characterize the retrograde flow of adhesion proteins (α6- and αLβ2-GFP integrins and mCherry-paxillin) in CHO.B2 cells plated on laminin and intercellular adhesion molecule 1 (ICAM-1) ligands respectively. STICS with a tunable frequency filter, in conjunction with nICS, measures two new transport parameters, the density and transport bias coefficient (a measure of the diffusive character of a flow/biased diffusion), showing that molecular flow in this cell system has a significant diffusive component. Our results suggest that the integrin-ligand interaction, along with the internal myosin-motor generated force, varies for different integrin-ligand pairs, consistent with previous results.

Berberine diminishes side population and down-regulates stem cell-associated genes in the pancreatic cancer cell lines PANC-1 and MIA PaCa-2.

PubMed

Park, S H; Sung, J H; Chung, N

2014-09-01

Cancer stem cells play an important role in metastasis and the relapse of drug resistant cancers. Side-population (SP) cells are capable of effluxing Hoechst 33342 dye and are referred to as cancer stem cells. We investigated the effect of berberine on pancreatic cancer stem cells of PANC-1 and MIA PaCa-2. For both cell lines, the proportions of SP cells in the presence of berberine were investigated and compared to the proportions in the presence of gemcitabine, a standard pancreatic anti-cancer drug. The proportions of SP cells in the PANC-1 and MIA PaCa-2 cell lines were about 9 and <0.1%, respectively. After berberine and gemcitabine treatments, the SP cell proportion of PANC-1 decreased to 5.7 ± 2.0 and 6.8 ± 0.8%, respectively, which compares to the control proportion of (9.7 ± 1.7). After berberine and gemcitabine treatment of PANC-1, of the four stem cell-associated genes (SOX2, POU5F1, NANOG, and NOTCH1), all but NOTCH1 were down-regulated. Unfortunately, the effect of berberine and gemcitabine treatments on MIA PaCa-2 SP cells could not be clearly observed because SP cells represented only a very small proportion of MIA PaCa-2 cells. However, SOX2, POU5F1, and NANOG genes were shown to be effectively down-regulated in the MIA PaCa-2 cell line as a whole. Taken together, these results indicate that berberine is as effective at targeting pancreatic cancer cell lines as gemcitabine. Therefore, we believe that POU5F1, SOX2, and NANOG can serve as potential markers, and berberine may be an effective anti-cancer agent when targeting human pancreatic cancer cells and/or their cancer stem cells.

Expression of DNA translesion synthesis polymerase η in head and neck squamous cell cancer predicts resistance to gemcitabine and cisplatin-based chemotherapy.

PubMed

Zhou, Wendi; Chen, Yih-wen; Liu, Xiyong; Chu, Peiguo; Loria, Sofia; Wang, Yafan; Yen, Yun; Chou, Kai-Ming

2013-01-01

The development of resistance against anticancer drugs has been a persistent clinical problem for the treatment of locally advanced malignancies in the head and neck mucosal derived squamous cell carcinoma (HNSCC). Recent evidence indicates that the DNA translesion synthesis (TLS) polymerase η (Pol η; hRad30a gene) reduces the effectiveness of gemcitabine/cisplatin. The goal of this study is to examine the relationship between the expression level of Pol η and the observed resistance against these chemotherapeutic agents in HNSCC, which is currently unknown. Sixty-four mucosal derived squamous cell carcinomas of head and neck (HNSCC) from 1989 and 2007 at the City of Hope National Medical Center (Duarte, CA) were retrospectively analyzed. Pretreatment samples were immunostained with anti-Pol η antibody and the correlation between the expression level of Pol η and clinical outcomes were evaluated. Forty-nine cases treated with platinum (n=40) or gemcitabine (n=9) based chemotherapy were further examined for Pol η expression level for comparison with patient response to chemotherapy. The expression of Pol η was elevated in 67% of the head and neck tumor samples. Pol η expression level was significantly higher in grade 1 to grade 2 tumors (well to moderately differentiated). The overall benefit rate (complete response+ partial response) in patients treated with platinum and gemcitabine based chemotherapy was 79.5%, where low Pol η level was significantly associated with high complete response rate (p=0.03), although not associated with overall survival. Furthermore, no significant correlation was observed between Pol η expression level with gender, age, tobacco/alcohol history, tumor stage and metastatic status. Our data suggest that Pol η expression may be a useful prediction marker for the effectiveness of platinum or gemcitabine based therapy for HNSCC.

Expression of DNA Translesion Synthesis Polymerase η in Head and Neck Squamous Cell Cancer Predicts Resistance to Gemcitabine and Cisplatin-Based Chemotherapy

PubMed Central

Zhou, Wendi; Chen, Yih-wen; Liu, Xiyong; Chu, Peiguo; Loria, Sofia; Wang, Yafan; Yen, Yun; Chou, Kai-Ming

2013-01-01

Purpose The development of resistance against anticancer drugs has been a persistent clinical problem for the treatment of locally advanced malignancies in the head and neck mucosal derived squamous cell carcinoma (HNSCC). Recent evidence indicates that the DNA translesion synthesis (TLS) polymerase η (Pol η; hRad30a gene) reduces the effectiveness of gemcitabine/cisplatin. The goal of this study is to examine the relationship between the expression level of Pol η and the observed resistance against these chemotherapeutic agents in HNSCC, which is currently unknown. Methods Sixty-four mucosal derived squamous cell carcinomas of head and neck (HNSCC) from 1989 and 2007 at the City of Hope National Medical Center (Duarte, CA) were retrospectively analyzed. Pretreatment samples were immunostained with anti-Pol η antibody and the correlation between the expression level of Pol η and clinical outcomes were evaluated. Forty-nine cases treated with platinum (n=40) or gemcitabine (n=9) based chemotherapy were further examined for Pol η expression level for comparison with patient response to chemotherapy. Results The expression of Pol η was elevated in 67% of the head and neck tumor samples. Pol η expression level was significantly higher in grade 1 to grade 2 tumors (well to moderately differentiated). The overall benefit rate (complete response+ partial response) in patients treated with platinum and gemcitabine based chemotherapy was 79.5%, where low Pol η level was significantly associated with high complete response rate (p=0.03), although not associated with overall survival. Furthermore, no significant correlation was observed between Pol η expression level with gender, age, tobacco/alcohol history, tumor stage and metastatic status. Conclusions Our data suggest that Pol η expression may be a useful prediction marker for the effectiveness of platinum or gemcitabine based therapy for HNSCC. PMID:24376779

Multicenter, Double-Blind, Placebo-Controlled, Randomized Phase II Trial of Gemcitabine/Cisplatin Plus Bevacizumab or Placebo in Patients With Malignant Mesothelioma

PubMed Central

Kindler, Hedy L.; Karrison, Theodore G.; Gandara, David R.; Lu, Charles; Krug, Lee M.; Stevenson, James P.; Jänne, Pasi A.; Quinn, David I.; Koczywas, Marianna N.; Brahmer, Julie R.; Albain, Kathy S.; Taber, David A.; Armato, Samuel G.; Vogelzang, Nicholas J.; Chen, Helen X.; Stadler, Walter M.; Vokes, Everett E.

2012-01-01

Purpose Gemcitabine plus cisplatin is active in malignant mesothelioma (MM), although single-arm phase II trials have reported variable outcomes. Vascular endothelial growth factor (VEGF) inhibitors have activity against MM in preclinical models. We added the anti-VEGF antibody bevacizumab to gemcitabine/cisplatin in a multicenter, double-blind, placebo-controlled randomized phase II trial in patients with previously untreated, unresectable MM. Patients and Methods Eligible patients had an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 1 and no thrombosis, bleeding, or major blood vessel invasion. The primary end point was progression-free survival (PFS). Patients were stratified by ECOG performance status (0 v 1) and histologic subtype (epithelial v other). Patients received gemcitabine 1,250 mg/m2 on days 1 and 8 every 21 days, cisplatin 75 mg/m2 every 21 days, and bevacizumab 15 mg/kg or placebo every 21 days for six cycles, and then bevacizumab or placebo every 21 days until progression. Results One hundred fifteen patients were enrolled at 11 sites; 108 patients were evaluable. Median PFS time was 6.9 months for the bevacizumab arm and 6.0 months for the placebo arm (P = .88). Median overall survival (OS) times were 15.6 and 14.7 months in the bevacizumab and placebo arms, respectively (P = .91). Partial response rates were similar (24.5% for bevacizumab v 21.8% for placebo; P = .74). A higher pretreatment plasma VEGF concentration (n = 56) was associated with shorter PFS (P = .02) and OS (P = .0066), independent of treatment arm. There were no statistically significant differences in toxicity of grade 3 or greater. Conclusion The addition of bevacizumab to gemcitabine/cisplatin in this trial did not significantly improve PFS or OS in patients with advanced MM. PMID:22665541

The serum miR-21 level serves as a predictor for the chemosensitivity of advanced pancreatic cancer, and miR-21 expression confers chemoresistance by targeting FasL.

PubMed

Wang, Peng; Zhuang, Liping; Zhang, Juan; Fan, Jie; Luo, Jianmin; Chen, Hao; Wang, Kun; Liu, Luming; Chen, Zhen; Meng, Zhiqiang

2013-06-01

miR-21 expression in cancer tissue has been reported to be associated with the clinical outcome and activity of gemcitabine in pancreatic cancer. However, resection is possible in only a minority of patients due to the advanced stages often present at the time of diagnosis, and safely obtaining sufficient quantities of pancreatic tumor tissue for molecular analysis is difficult at the unresectable stages. In this study, we investigated whether the serum level of miR-21 could be used as a predictor of chemosensitivity. We tested the levels of serum miR-21 in a cohort of 177 cases of advanced pancreatic cancer who received gemcitabine-based palliative chemotherapy. We found that a high level of miR-21 in the serum was significantly correlated with a shortened time-to-progression (TTP) and a lower overall survival (OS). The serum miR-21 level was an independent prognostic factor for both the TTP and the OS (HR 1.920; 95% CI, 1.274-2.903, p = 0.002 for TTP and HR 1.705; 95% CI, 1.147-2.535, p = 0.008 for OS). The results from a functional study showed that gemcitabine exposure down-regulated miR-21 expression and up-regulated FasL expression. The increased FasL expression following gemcitabine treatment induced cancer cell apoptosis, whereas the ectopic expression of miR-21 partially protected the cancer cells from gemcitabine-induced apoptosis. Additionally, we confirmed that FasL was a direct target of miR-21. Therefore, the serum level of miR-21 may serve as a predictor of chemosensitivity in advanced pancreatic cancer. Additionally, we identified a new mechanism of chemoresistance mediated by the effects of miR-21 on the FasL/Fas pathway. Copyright © 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Efficacy and Safety of First-Line Necitumumab Plus Gemcitabine and Cisplatin Versus Gemcitabine and Cisplatin in East Asian Patients with Stage IV Squamous Non-small Cell Lung Cancer: A Subgroup Analysis of the Phase 3, Open-Label, Randomized SQUIRE Study.

PubMed

Park, Keunchil; Cho, Eun Kyung; Bello, Maximino; Ahn, Myung-Ju; Thongprasert, Sumitra; Song, Eun-Kee; Soldatenkova, Victoria; Depenbrock, Henrik; Puri, Tarun; Orlando, Mauro

2017-10-01

The phase 3 randomized SQUIRE study revealed significantly longer overall survival (OS) and progression-free survival (PFS) for necitumumab plus gemcitabine and cisplatin (neci+GC) than for gemcitabine and cisplatin alone (GC) in 1,093 patients with previously untreated advanced squamous non-small cell lung cancer (NSCLC). This post hoc subgroup analysis assessed the efficacy and safety of neci+GC among East Asian (EA) patients enrolled in the study. All patients received up to six 3-week cycles of gemcitabine (days 1 and 8, 1,250 mg/m²) and cisplatin (day 1, 75 mg/m²). Patients in the neci+GC arm also received necitumumab (days 1 and 8, 800 mg) until disease progression or unacceptable toxicity. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated from stratified Cox proportional hazards models. In EA patients, there were improvements for neci+GC (n=43) versus GC (n=41) in OS (HR, 0.805; 95% CI, 0.484 to 1.341) and PFS (HR, 0.720; 95% CI, 0.439 to 1.180), consistent with the results for non-EA patients observed in the present study. The overall safety data were consistent between EA and non-EA patients. A numerically higher proportion of patients experienced serious adverse events (AEs), grade ≥ 3 AEs, and AEs with an outcome of death for neci+GC versus GC in EA patients and EA patients versus non-EA patients for neci+GC. Although limited by the small sample size and post hoc nature of the analysis, these findings are consistent with those of the overall study and suggest that neci+GC offers a survival advantage and favorable benefit/risk for EA patients with advanced squamous NSCLC.

Palonosetron with aprepitant plus dexamethasone to prevent chemotherapy-induced nausea and vomiting during gemcitabine/cisplatin in urothelial cancer patients.

PubMed

Kitamura, Hiroshi; Takahashi, Atsushi; Hotta, Hiroshi; Kato, Ryuichi; Kunishima, Yasuharu; Takei, Fumiyasu; Horita, Hiroki; Masumori, Naoya

2015-10-01

To evaluate the appearance of chemotherapy-induced nausea and vomiting, and to compare the antiemetic efficacy of the triple combination of palonosetron, aprepitant and dexamethasone with that of our old regimen using first-generation 5-hydroxytryptamine 3-receptor antagonists and dexamethasone during gemcitabine and cisplatin chemotherapy in patients with advanced urothelial cancer. We carried out a multi-institutional study including 122 patients who received gemcitabine and cisplatin for advanced urothelial cancer between February 2005 and January 2012. Uncontrolled chemotherapy-induced nausea and vomiting events were identified through records of nausea and vomiting, additional infusion, rescue medications, and/or records of food intake. First-generation 5-hydroxytryptamine 3-receptor antagonists (ondansetron or granisetron) plus dexamethasone were used for 75 patients (cohort 1), and palonosetron with dexamethasone plus aprepitant for 47 patients (cohort 2). Patients in cohort 2 had significantly higher complete response (defined as no emetic episodes and no rescue medication use) rates than those in cohort 1 during the overall phase in the first cycle (85.7% vs 65.3%, P = 0.012), and all cycles (78.7% vs 50.7%, P = 0.0019) of gemcitabine and cisplatin. Patients in cohort 2 were more likely to achieve more favorable chemotherapy-induced nausea and vomiting control; that is, a lower grade of nausea, vomiting or anorexia, lower incidence of rescue therapy required, and shorter time to become chemotherapy-induced nausea- and vomiting-free than patients in cohort 1. The present results show that palonosetron in combination with aprepitant and dexamethasone is more effective to prevent chemotherapy-induced nausea and vomiting in urothelial cancer patients treated with gemcitabine and cisplatin than first-generation 5-hydroxytryptamine 3-receptor antagonists plus dexamethasone. © 2015 The Japanese Urological Association.

Prognostic role of human equilibrative transporter 1 (hENT1) in patients with resected gastric cancer.

PubMed

Santini, Daniele; Vincenzi, Bruno; Fratto, Maria Elisabetta; Perrone, Giuseppe; Lai, Raymond; Catalano, Vincenzo; Cass, Carol; Ruffini, Pier Adelchi; Spoto, Chiara; Muretto, Pietro; Rizzo, Sergio; Muda, Andrea Onetti; Mackey, John R; Russo, Antonio; Tonini, Giuseppe; Graziano, Francesco

2010-05-01

Nucleoside transporter proteins are specialized proteins that mediate the transport of nucleosides and nucleoside analog drugs across the plasma membrane. The human equilibrative nucleoside transporter 1 (hENT1) is a member of these proteins and mediates cellular entry of gemcitabine, cytarabine, and fludarabine. The hENT1 expression has been demonstrated to be related with prognosis and activity of gemcitabine-based therapy in breast, ampullary, lung, and pancreatic cancer. We investigated the immunohistochemical expression of hENT in tumor samples from 111 patients with resected gastric adenocarcinoma, correlating these data with clinical parameters and disease outcomes. None of the patients received chemotherapy or radiation therapy before or after surgery as a part of an adjuvant or neoadjuvant program. On univariate survival analysis, the hENT1 expression was associated with overall survival (OS) and disease free survival (DFS). Specifically, those patients with overexpression of hENT1 showed a shorter OS (P = 0.021) and a shorter DFS (P = 0.033). Considering only the node positive patients, higher hENT levels were associated with significantly shorter median DFS (21.7 months; 95% CI 11.1-32.4) compared with patients with low expression of hENT1. The hENT1 expression was defined, in the lymph-node positive patients, as an independent prognostic factor (P = 0.019). Furthermore, considering only patients with diffuse or mixed tumors and lymph-node positive, the expression of hENT1 was strongly related with DFS and OS. Immunohistochemistry for the hENT1 protein carries prognostic information in patients with resected gastric cancer and holds promise as a predictive factor in chemotherapy decisions.

Measurement of Single Channel Currents from Cardiac Gap Junctions

NASA Astrophysics Data System (ADS)

Veenstra, Richard D.; Dehaan, Robert L.

1986-08-01

Cardiac gap junctions consist of arrays of integral membrane proteins joined across the intercellular cleft at points of cell-to-cell contact. These junctional proteins are thought to form pores through which ions can diffuse from cytosol to cytosol. By monitoring whole-cell currents in pairs of embryonic heart cells with two independent patch-clamp circuits, the properties of single gap junction channels have been investigated. These channels had a conductance of about 165 picosiemens and underwent spontaneous openings and closings that were independent of voltage. Channel activity and macroscopic junctional conductance were both decreased by the uncoupling agent 1-octanol.

The stratified syncytium of the vertebrate lens.

PubMed

Shi, Yanrong; Barton, Kelly; De Maria, Alicia; Petrash, J Mark; Shiels, Alan; Bassnett, Steven

2009-05-15

The fusion of cells to generate syncytial tissues is a crucial event in the development of many organisms. In the lens of the vertebrate eye, proteins and other macromolecules diffuse from cell to cell via the large molecule diffusion pathway (LMDP). We used the tamoxifen-induced expression of GFP to investigate the nature and role of the LMDP in living, intact lenses. Our data indicate that the LMPD preferentially connects cells lying within a stratum of the lens cortex and that formation of the LMPD depends on the expression of Lim2, a claudin-like molecule. The conduits for intercellular protein exchange are most likely regions of partial cellular fusion, which are commonly observed in wild-type lenses but rare or absent in Lim2-deficient lenses. The observation that lens tissue constitutes a stratified syncytium has implications for the transparency, refractive function and pathophysiology of the tissue.

Icotinib plus gemcitabine for metastatic pancreatic cancer: A case report

PubMed Central

Zhao, Jing; Shen, Hong; Hu, Han-Guang; Huang, Jian-Jin

2015-01-01

A large majority of patients diagnosed with pancreatic cancer have advanced metastatic disease with unresectable malignancies. Despite treatment advances, the survival benefit from chemotherapeutic regimens and targeted drugs is limited. Moreover, their application is limited in China because of high toxicity and cost. Recently, inhibitors of epidermal growth factor receptor activity have shown promise for the treatment of solid cancers when used in combination with standard therapy. However, these drugs have not been evaluated extensively for the treatment of pancreatic cancer. Here, we report the treatment of a 64-year-old male with metastatic pancreatic cancer using a novel regimen of icotinib with gemcitabine. Marked shrinkage of the mass was observed after two treatment cycles, and partial remission was achieved. The abdominal pain was relieved. The adverse effects were tolerable and treatment cost was acceptable. This is the first reported case for the treatment of advanced pancreatic cancer with icotinib plus gemcitabine and demonstrates a promising therapeutic alternative. PMID:25805958

Icotinib plus gemcitabine for metastatic pancreatic cancer: a case report.

PubMed

Zhao, Jing; Shen, Hong; Hu, Han-Guang; Huang, Jian-Jin

2015-03-21

A large majority of patients diagnosed with pancreatic cancer have advanced metastatic disease with unresectable malignancies. Despite treatment advances, the survival benefit from chemotherapeutic regimens and targeted drugs is limited. Moreover, their application is limited in China because of high toxicity and cost. Recently, inhibitors of epidermal growth factor receptor activity have shown promise for the treatment of solid cancers when used in combination with standard therapy. However, these drugs have not been evaluated extensively for the treatment of pancreatic cancer. Here, we report the treatment of a 64-year-old male with metastatic pancreatic cancer using a novel regimen of icotinib with gemcitabine. Marked shrinkage of the mass was observed after two treatment cycles, and partial remission was achieved. The abdominal pain was relieved. The adverse effects were tolerable and treatment cost was acceptable. This is the first reported case for the treatment of advanced pancreatic cancer with icotinib plus gemcitabine and demonstrates a promising therapeutic alternative.

Lipid composition of the stratum corneum and cutaneous water loss in birds along an aridity gradient.

PubMed

Champagne, Alex M; Muñoz-Garcia, Agustí; Shtayyeh, Tamer; Tieleman, B Irene; Hegemann, Arne; Clement, Michelle E; Williams, Joseph B

2012-12-15

Intercellular and covalently bound lipids within the stratum corneum (SC), the outermost layer of the epidermis, are the primary barrier to cutaneous water loss (CWL) in birds. We compared CWL and intercellular SC lipid composition in 20 species of birds from desert and mesic environments. Furthermore, we compared covalently bound lipids with CWL and intercellular lipids in the lark family (Alaudidae). We found that CWL increases in birds from more mesic environments, and this increase was related to changes in intercellular SC lipid composition. The most consistent pattern that emerged was a decrease in the relative amount of cerebrosides as CWL increased, a pattern that is counterintuitive based on studies of mammals with Gaucher disease. Although covalently bound lipids in larks did not correlate with CWL, we found that covalently bound cerebrosides correlated positively with intercellular cerebrosides and intercellular cholesterol ester, and intercellular cerebrosides correlated positively with covalently bound free fatty acids. Our results led us to propose a new model for the organization of lipids in the avian SC, in which the sugar moieties of cerebrosides lie outside of intercellular lipid layers, where they may interdigitate with adjacent intercellular cerebrosides or with covalently bound cerebrosides.

Inhibition of CHK1 sensitizes Ewing sarcoma cells to the ribonucleotide reductase inhibitor gemcitabine

PubMed Central

Goss, Kelli L; Koppenhafer, Stacia L; Harmoney, Kathryn M; Terry, William W; Gordon, David J

2017-01-01

Ewing sarcoma is a bone and soft tissue sarcoma that occurs in children and young adults. The EWS-FLI1 gene fusion is the driver mutation in most Ewing sarcoma tumors and functions, in part, as an aberrant transcription factor. We recently identified that Ewing sarcoma cells are sensitive to inhibition of ribonucleotide reductase (RNR), which catalyzes the formation of deoxyribonucleotides from ribonucleotides. In this report, we show that Ewing sarcoma cells are sensitive to treatment with clofarabine, which is a nucleoside analogue and allosteric inhibitor of RNR. However, clofarabine is a reversible inhibitor of RNR and we found that the effect of clofarabine is limited when using a short (6-hour) drug treatment. Gemcitabine, on the other hand, is an irreversible inhibitor of the RRM1 subunit of RNR and this drug induces apoptosis in Ewing sarcoma cells when used in both 6-hour and longer drug treatments. Treatment of Ewing sarcoma cells with gemcitabine also results in activation of checkpoint kinase 1 (CHK1), which is a critical mediator of cell survival in the setting of impaired DNA replication. Notably, inhibition of CHK1 function in Ewing sarcoma cells using a small-molecule CHK1 inhibitor, or siRNA knockdown, in combination with gemcitabine results in increased toxicity both in vitro and in vivo in a mouse xenograft experiment. Overall, our results provide insight into Ewing sarcoma biology and identify a candidate therapeutic target, and drug combination, in Ewing sarcoma. PMID:29152060

Folate receptor-specific, redox-responsive mesoporous silica nanoparticles for the simultaneous delivery of cisplatin and gemcitabine to treat cancer

NASA Astrophysics Data System (ADS)

Fink, Eric Douglas

Nanoparticles are an innovative platform for cancer treatment that reduces systemic toxicity and allows for active targeting of tumor sites to enhance the therapeutic efficacy. Mesoporous silica nanoparticles (MSNs) have emerged as an attractive drug delivery system due to their high surface area, vast functionalization potential, and biocompatibility. The main goal of this project is to develop a target-specific stimuli-responsive MSN based drug delivery system for the simultaneous delivery of cisplatin and gemcitabine. Both drugs were chemically attached to the MSNs via stimuli-responsive linkers that respond to the high reducing environment and low pH characteristic of cancer cells. The MSN materials fabricated in this work were successfully synthesized and characterized with a wide variety of spectroscopic and microscopic techniques. The loading of cisplatin and gemcitabine and their release profile under high reducing conditions were determined using atomic absorption (AA) and UV-vis spectroscopy, respectively. In vitro toxicity studies were performed on human cervical cancer (HeLa) cells in the presence of different ratios of cisplatin/gemcitabine drugs to determine the best ratio to kill HeLa cells. Based on this data, MSN materials carrying individual drugs and the corresponding combinatorial nanoparticles were fabricated and their in vitro cytotoxicity evaluated in HeLa and pancreatic cancer cells (AsPC1 and BxPC-3). The next step in this project was to further modify with folic acid to enhance its targeting ability toward cancer cells overexpressing folate receptors.

A phase II trial of gemcitabine plus carboplatin in advanced transitional cell carcinoma of the urothelium.

PubMed

Xu, Nong; Zhang, Xiao Chen; Xiong, Jian Ping; Fang, Wei Jia; Yu, Lan Fang; Qian, Jiong; Zhang, Ling

2007-06-09

Recent studies have demonstrated the effectiveness of cisplatin-based combinations in patients with advanced transitional cell carcinoma(TCC) of the urothelium. Concern over cisplatin toxicity instigated a search for alternative regimens. The aim of the study was to evaluate the activity and tolerability of gemcitabine plus carboplatin combination as first-line treatment in patients with advanced transitional cell carcinoma of the urothelium. Patients with advanced TCC were treated with gemcitabine 1200 mg/m2 on days 1 and 8 and carboplatin area under the concentration-time curve(AUC) 5 on day 1 every 21 days. Out of 41 patients, thirty-nine were evaluable for efficacy and 41 for toxicity. A median of 5 cycles (range 1-6) was administered. Overall response rate was 46.2% (95% confidence interval: 32-65%) including 10.3% complete responses and 35.9% partial responses. The median time to progression and median overall survival were 7.5 months (95% confidence interval: 6.6-8.4 months) and 13.6 months (95% confidence interval: 10.2-17.0 months), respectively. Grade 3/4 neutropenia, anemia and thrombocytopenia were observed in 36.6%, 26.8, and 24.4% of patients, respectively. Non-hematological toxicity was generally mild. Grade 3 vomiting occurred in 1 (2.4%) patients. The gemcitabine plus carboplatin combination is active in advanced TCC with acceptable toxicity and needs to be evaluated further and compared with other non-cisplatin-containing regimens. ISRCTN88259320.

An Intergroup Randomized Phase II Study of Bevacizumab or Cetuximab in Combination with Gemcitabine and in Combination with Chemoradiation in Patients with Resected Pancreatic Carcinoma: A Trial of the ECOG-ACRIN Cancer Research Group (E2204).

PubMed

Berlin, Jordan D; Feng, Yang; Catalano, Paul; Abbruzzese, James L; Philip, Philip A; McWilliams, Robert R; Lowy, Andrew M; Benson, Al B; Blackstock, A William

2018-01-01

Evaluate toxicity of two treatment arms, A (cetuximab) and B (bevacizumab), when combined with gemcitabine, and chemoradiation in patients with completely resected pancreatic carcinoma. Secondary objectives included overall survival (OS) and disease-free survival (DFS). Patients with R0/R1 resection were randomized 1:1 to cetuximab or bevacizumab administered in combination with gemcitabine for two treatment cycles. Next three cycles included concurrent cetuximab/bevacizumab plus chemoradiation, followed by one cycle of cetuximab/bevacizumab. Cycles 7-12 included cetuximab/bevacizumab with gemcitabine. Cycles were 2 weeks. Frequency of specific toxicities was summarized for each treatment arm at two times during the study, after chemotherapy but prior to chemoradiation and after all therapy. A total of 127 patients were randomized (A, n = 65; B, n = 62). Prior to chemoradiation, the overall rate for toxicities of interest was 10% for arm A and 2% for arm B. After all therapy, the overall rates for toxicities of interest were 30 and 25% for arms A and B, respectively. Overall median OS and DFS were 17 and 11 months, respectively, which is not a significant improvement over expected survival rates for historical controls. Both treatments were tolerable with manageable toxicities, and were safe enough for a phase III trial had this been indicated. © 2017 S. Karger AG, Basel.

Gemcitabine diphosphate choline is a major metabolite linked to the Kennedy pathway in pancreatic cancer models in vivo

PubMed Central

Bapiro, T E; Frese, K K; Courtin, A; Bramhall, J L; Madhu, B; Cook, N; Neesse, A; Griffiths, J R; Tuveson, D A; Jodrell, D I; Richards, F M

2014-01-01

Background: The modest benefits of gemcitabine (dFdC) therapy in patients with pancreatic ductal adenocarcinoma (PDAC) are well documented, with drug delivery and metabolic lability cited as important contributing factors. We have used a mouse model of PDAC: KRASG12D; p53R172H; pdx-Cre (KPC) that recapitulates the human disease to study dFdC intra-tumoural metabolism. Methods: LC-MS/MS and NMR were used to measure drug and physiological analytes. Cytotoxicity was assessed by the Sulphorhodamine B assay. Results: In KPC tumour tissue, we identified a new, Kennedy pathway-linked dFdC metabolite (gemcitabine diphosphate choline (GdPC)) present at equimolar amounts to its precursor, the accepted active metabolite gemcitabine triphosphate (dFdCTP). Utilising additional subcutaneous PDAC tumour models, we demonstrated an inverse correlation between GdPC/dFdCTP ratios and cytidine triphosphate (CTP). In tumour homogenates in vitro, CTP inhibited GdPC formation from dFdCTP, indicating competition between CTP and dFdCTP for CTP:phosphocholine cytidylyltransferase (CCT). As the structure of GdPC precludes entry into cells, potential cytotoxicity was assessed by stimulating CCT activity using linoleate in KPC cells in vitro, leading to increased GdPC concentration and synergistic growth inhibition after dFdC addition. Conclusions: GdPC is an important element of the intra-tumoural dFdC metabolic pathway in vivo. PMID:24874484

Investigation into metastatic processes and the therapeutic effects of gemcitabine on human pancreatic cancer using an orthotopic SUIT-2 pancreatic cancer mouse model

PubMed Central

Higuchi, Tamami; Yokobori, Takehiko; Naito, Tomoharu; Kakinuma, Chihaya; Hagiwara, Shinji; Nishiyama, Masahiko; Asao, Takayuki

2018-01-01

Prognosis of pancreatic cancer is poor, thus the development of novel therapeutic drugs is necessary. During preclinical studies, appropriate models are essential for evaluating drug efficacy. The present study sought to determine the ideal pancreatic cancer mouse model for reliable preclinical testing. Such a model could accurately reflect human pancreatic cancer phenotypes and predict future clinical trial results. Systemic pathology analysis was performed in an orthotopic transplantation model to prepare model mice for use in preclinical studies, mimicking the progress of human pancreatic cancer. The location and the timing of inoculated cancer cell metastases, pathogenesis and cause of fatality were analyzed. Furthermore, the efficacy of gemcitabine, a key pancreatic cancer drug, was evaluated in this model where liver metastasis and peritoneal dissemination occur. Results indicated that the SUIT-2 orthotopic pancreatic cancer model was similar to the phenotypic sequential progression of human pancreatic cancer, with extra-pancreatic invasion, intra-peritoneal dissemination and other hematogenous organ metastases. Notably, survival was prolonged by administering gemcitabine to mice with metastasized pancreatic cancer. Furthermore, the detailed effects of gemcitabine on the primary tumor and metastatic tumor lesions were pathologically evaluated in mice. The present study indicated the model accurately depicted pancreatic cancer development and metastasis. Furthermore, the detailed effects of pancreatic cancer drugs on the primary tumor and on metastatic tumor lesions. We present this model as a potential new standard for new drug development in pancreatic cancer. PMID:29435042

Signaling from the Podocyte Intercellular Junction to the Actin Cytoskeleton

PubMed Central

George, Britta; Holzman, Lawrence B.

2012-01-01

Observations of hereditary glomerular disease support the contention that podocyte intercellular junction proteins are essential for junction formation and maintenance. Genetic deletion of most of these podocyte intercellular junction proteins results in foot process effacement and proteinuria. This review focuses on the current understanding of molecular mechanisms by which podocyte intercellular junction proteins such as the Nephrin-Neph1-Podocin receptor complex coordinate cytoskeletal dynamics and thus intercellular junction formation, maintenance and injury-dependent remodeling. PMID:22958485

Cavitation of intercellular spaces is critical to establishment of hydraulic properties of compression wood of Chamaecyparis obtusa seedlings

PubMed Central

Nakaba, Satoshi; Hirai, Asami; Kudo, Kayo; Yamagishi, Yusuke; Yamane, Kenichi; Kuroda, Katsushi; Nugroho, Widyanto Dwi; Kitin, Peter; Funada, Ryo

2016-01-01

Background and Aims When the orientation of the stems of conifers departs from the vertical as a result of environmental influences, conifers form compression wood that results in restoration of verticality. It is well known that intercellular spaces are formed between tracheids in compression wood, but the function of these spaces remains to be clarified. In the present study, we evaluated the impact of these spaces in artificially induced compression wood in Chamaecyparis obtusa seedlings. Methods We monitored the presence or absence of liquid in the intercellular spaces of differentiating xylem by cryo-scanning electron microscopy. In addition, we analysed the relationship between intercellular spaces and the hydraulic properties of the compression wood. Key Results Initially, we detected small intercellular spaces with liquid in regions in which the profiles of tracheids were not rounded in transverse surfaces, indicating that the intercellular spaces had originally contained no gases. In the regions where tracheids had formed secondary walls, we found that some intercellular spaces had lost their liquid. Cavitation of intercellular spaces would affect hydraulic conductivity as a consequence of the induction of cavitation in neighbouring tracheids. Conclusions Our observations suggest that cavitation of intercellular spaces is the critical event that affects not only the functions of intercellular spaces but also the hydraulic properties of compression wood. PMID:26818592

Phytoalexin Induction in French Bean 1

PubMed Central

Dixon, Richard A.; Dey, Prakash M.; Lawton, Michael A.; Lamb, Christopher J.

1983-01-01

Treatment of hypocotyl sections or cell suspension cultures of dwarf French bean (Phaseolus vulgaris L.) with an abiotic elicitor (denatured ribonuclease A) resulted in increased extractable activity of the enzyme l-phenylalanine ammonia-lyase. This induction could be transmitted from treated cells through a dialysis membrane to cells which were not in direct contact with the elicitor. In hypocotyl sections, induction of isoflavonoid phytoalexin accumulation was also transmitted across a dialysis membrane, although levels of insoluble, lignin-like phenolic material remained unchanged in elicitor-treated and control sections. In bean cell suspension cultures, the induction of phenylalanine ammonia-lyase in cells separated from ribonuclease-treated cells by a dialysis membrane was also accompanied by increases in the activities of chalcone synthase and chalcone isomerase, two enzymes previously implicated in the phytoalexin defense response. Such intercellular transmission of elicitation did not occur in experiments with cells treated with a biotic elicitor preparation heat-released from the cell walls of the bean pathogen Colletotrichum lindemuthianum. The results confirm and extend previous suggestions that a low molecular weight, diffusible factor of host plant origin is involved (in French bean) in the intercellular transmission of the elicitation response to abiotic elicitors. PMID:16662813

Loss of intercellular adhesion leads to differential accumulation of hypericin in bladder cancer

NASA Astrophysics Data System (ADS)

Lucky, S. Sasidharan; Bhuvaneswari, Ramaswamy; Chin, William W. L.; Lau, Weber K. O.; Olivo, Malini C. D.

2009-06-01

Photodynamic diagnosis (PDD) exploits the photoactive nature of certain compounds, namely photosensitizers, in order to enhance the visual demarcation between normal and neoplastic tissue. Hypericin is one such potent photosensitizer that preferentially accumulate in neoplastic tissue, and fluoresce in the visible spectrum when illuminated with light of an appropriate wavelength. In our study, we investigated the role of E-cadherin in the selective permeation of hypericin in bladder cancer tissues. Clinical studies were done on a series of 43 histologically graded bladder cancer biopsy specimens, obtained from 28 patients who received intravesical instillations with 8μM hypericin solution for at least 2 hours. Immunohistochemical staining was used to assess the expression of E-cadherin, in the cryosectioned tissues. Hypericin uptake was examined by fluorescence microscopy. Immunohistochemical staining showed a clear expression of E-cadherin along the urothelial lining of the normal and pre-malignant tissues. Partial expression of these cell adhesion molecules were still observed in malignant tissues, however there was a loss of expression to variable extends along the urothelium. Thus, loss of intercellular adhesion can be associated with enhanced hypericin permeation through paracellular diffusion.

Pan-mTOR inhibitor MLN0128 is effective against intrahepatic cholangiocarcinoma in mice.

PubMed

Zhang, Shanshan; Song, Xinhua; Cao, Dan; Xu, Zhong; Fan, Biao; Che, Li; Hu, Junjie; Chen, Bin; Dong, Mingjie; Pilo, Maria G; Cigliano, Antonio; Evert, Katja; Ribback, Silvia; Dombrowski, Frank; Pascale, Rosa M; Cossu, Antonio; Vidili, Gianpaolo; Porcu, Alberto; Simile, Maria M; Pes, Giovanni M; Giannelli, Gianluigi; Gordan, John; Wei, Lixin; Evert, Matthias; Cong, Wenming; Calvisi, Diego F; Chen, Xin

2017-12-01

Intrahepatic cholangiocarcinoma (ICC) is a lethal malignancy without effective treatment options. MLN0128, a second generation pan-mTOR inhibitor, shows efficacy for multiple tumor types. We evaluated the therapeutic potential of MLN0128 vs. gemcitabine/oxaliplatin in a novel ICC mouse model. We established a novel ICC mouse model via hydrodynamic transfection of activated forms of AKT (myr-AKT) and Yap (YapS127A) protooncogenes (that will be referred to as AKT/YapS127A). Genetic approaches were applied to study the requirement of mTORC1 and mTORC2 in mediating AKT/YapS127A driven tumorigenesis. Gemcitabine/oxaliplatin and MLN0128 were administered in AKT/YapS127A tumor-bearing mice to study their anti-tumor efficacy in vivo. Multiple human ICC cell lines were used for in vitro experiments. Hematoxylin and eosin staining, immunohistochemistry and immunoblotting were applied for the characterization and mechanistic study. Co-expression of myr-AKT and YapS127A promoted ICC development in mice. Both mTORC1 and mTORC2 complexes were required for AKT/YapS127A ICC development. Gemcitabine/oxaliplatin had limited efficacy in treating late stage AKT/YapS127A ICC. In contrast, partial tumor regression was achieved when MLN0128 was applied in the late stage of AKT/YapS127A cholangiocarcinogenesis. Furthermore, when MLN0128 was administered in the early stage of AKT/YapS127A carcinogenesis, it led to disease stabilization. Mechanistically, MLN0128 efficiently inhibited AKT/mTOR signaling both in vivo and in vitro, inducing strong ICC cell apoptosis and only marginally affecting proliferation. This study suggests that mTOR kinase inhibitors may be beneficial for the treatment of ICC, even in tumors that are resistant to standard of care chemotherapeutics, such as gemcitabine/oxaliplatin-based regimens, especially in the subset of tumors exhibiting activated AKT/mTOR cascade. Lay summary: We established a novel mouse model of intrahepatic cholangiocarcinoma (ICC). Using this new preclinical model, we evaluated the therapeutic potential of mTOR inhibitor MLN0128 vs. gemcitabine/oxaliplatin (the standard chemotherapy for ICC treatment). Our study shows the anti-neoplastic potential of MLN0128, suggesting that it may be superior to gemcitabine/oxaliplatin-based chemotherapy for the treatment of ICC, especially in the tumors exhibiting activated AKT/mTOR cascade. Copyright © 2017 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Oxygen diffusion: an enzyme-controlled variable parameter.

PubMed

Erdmann, Wilhelm; Kunke, Stefan

2014-01-01

Previous oxygen microelectrode studies have shown that the oxygen diffusion coefficient (DO₂) increases during extracellular PO₂ decreases, while intracellular PO₂ remained unchanged and thus cell function (spike activity of neurons). Oxygen dependency of complex multicellular organisms requires a stable and adequate oxygen supply to the cells, while toxic concentrations have to be avoided. Oxygen brought to the tissue by convection diffuses through the intercellular and cell membranes, which are potential barriers to diffusion. In gerbil brain cortex, PO₂ and DO₂ were measured by membrane-covered and by bare gold microelectrodes, as were also spike potentials. Moderate respiratory hypoxia was followed by a primary sharp drop of tissue PO₂ that recovered to higher values concomitant with an increase of DO₂. A drop in intracellular PO₂ recovered immediately. Studies on the abdominal ganglion of aplysia californica showed similar results.Heterogeneity is a feature of both normal oxygen supply to tissue and supply due to a wide range of disturbances in oxygen supply. Oxygen diffusion through membranes is variable thereby ensuring adequate intracellular PO₂. Cell-derived glucosamine oxidase seems to regulate the polymerization/depolymerisation ratio of membrane mucopolysaccharides and thus oxygen diffusion.Variability of oxygen diffusion is a decisive parameter for regulating the supply/demand ratio of oxygen supply to the cell; this occurs in highly developed animals as well as in species of a less sophisticated nature. Autoregulation of oxygen diffusion is as important as the distribution/perfusion ratio of the capillary meshwork and as the oxygen extraction ratio in relation to oxygen consumption of the cell. Oxygen diffusion resistance is the cellular protection against luxury oxygen supply (which can result in toxic oxidative species leading to mutagenesis).

A novel individual-cell-based mathematical model based on multicellular tumour spheroids for evaluating doxorubicin-related delivery in avascular regions.

PubMed

Liu, Jiali; Yan, Fangrong; Chen, Hongzhu; Wang, Wenjie; Liu, Wenyue; Hao, Kun; Wang, Guangji; Zhou, Fang; Zhang, Jingwei

2017-09-01

Effective drug delivery in the avascular regions of tumours, which is crucial for the promising antitumour activity of doxorubicin-related therapy, is governed by two inseparable processes: intercellular diffusion and intracellular retention. To accurately evaluate doxorubicin-related delivery in the avascular regions, these two processes should be assessed together. Here we describe a new approach to such an assessment. An individual-cell-based mathematical model based on multicellular tumour spheroids was developed that describes the different intercellular diffusion and intracellular retention kinetics of doxorubicin in each cell layer. The different effects of a P-glycoprotein inhibitor (LY335979) and a hypoxia inhibitor (YC-1) were quantitatively evaluated and compared, in vitro (tumour spheroids) and in vivo (HepG2 tumours in mice). This approach was further tested by evaluating in these models, an experimental doxorubicin derivative, INNO 206, which is in Phase II clinical trials. Inhomogeneous, hypoxia-induced, P-glycoprotein expression compromised active transport of doxorubicin in the central area, that is, far from the vasculature. LY335979 inhibited efflux due to P-glycoprotein but limited levels of doxorubicin outside the inner cells, whereas YC-1 co-administration specifically increased doxorubicin accumulation in the inner cells without affecting the extracellular levels. INNO 206 exhibited a more effective distribution profile than doxorubicin. The individual-cell-based mathematical model accurately evaluated and predicted doxorubicin-related delivery and regulation in the avascular regions of tumours. The described framework provides a mechanistic basis for the proper development of doxorubicin-related drug co-administration profiles and nanoparticle development and could avoid unnecessary clinical trials. © 2017 The British Pharmacological Society.

Intercellular salicylic acid accumulation during compatible and incompatible Arabidopsis-Pseudomonas syringae interactions

PubMed Central

Wilson, Daniel C; Carella, Philip; Cameron, Robin K

2014-01-01

The phytohormone salicylic acid (SA) plays an important role in several disease resistance responses. During the Age-Related Resistance (ARR) response that occurs in mature Arabidopsis responding to Pseudomonas syringae pv tomato (Pst), SA accumulates in the intercellular space where it may act as an antimicrobial agent. Recently we measured intracellular and intercellular SA levels in young, ARR-incompetent plants responding to virulent and avirulent strains of Pst to determine if intercellular SA accumulation is a component of additional defense responses to Pst. In young plants virulent Pst suppressed both intra- and intercellular SA accumulation in a coronatine-dependent manner. In contrast, high levels of intra- and intercellular SA accumulated in response to avirulent Pst. Our results support the idea that SA accumulation in the intercellular space is an important component of multiple defense responses. Future research will include understanding how mature plants counteract the effects of coronatine during the ARR response. PMID:25763618

Investigation of Intercellular Salicylic Acid Accumulation during Compatible and Incompatible Arabidopsis-Pseudomonas syringae Interactions Using a Fast Neutron-Generated Mutant Allele of EDS5 Identified by Genetic Mapping and Whole-Genome Sequencing

PubMed Central

Catana, Vasile; Golding, Brian; Weretilnyk, Elizabeth A.; Cameron, Robin K.

2014-01-01

A whole-genome sequencing technique developed to identify fast neutron-induced deletion mutations revealed that iap1-1 is a new allele of EDS5 (eds5-5). RPS2-AvrRpt2-initiated effector-triggered immunity (ETI) was compromised in iap1-1/eds5-5 with respect to in planta bacterial levels and the hypersensitive response, while intra- and intercellular free salicylic acid (SA) accumulation was greatly reduced, suggesting that SA contributes as both an intracellular signaling molecule and an antimicrobial agent in the intercellular space during ETI. During the compatible interaction between wild-type Col-0 and virulent Pseudomonas syringae pv. tomato (Pst), little intercellular free SA accumulated, which led to the hypothesis that Pst suppresses intercellular SA accumulation. When Col-0 was inoculated with a coronatine-deficient strain of Pst, high levels of intercellular SA accumulation were observed, suggesting that Pst suppresses intercellular SA accumulation using its phytotoxin coronatine. This work suggests that accumulation of SA in the intercellular space is an important component of basal/PAMP-triggered immunity as well as ETI to pathogens that colonize the intercellular space. PMID:24594657

A two-dimensional microscale model of gas exchange during photosynthesis in maize (Zea mays L.) leaves.

PubMed

Retta, Moges; Ho, Quang Tri; Yin, Xinyou; Verboven, Pieter; Berghuijs, Herman N C; Struik, Paul C; Nicolaï, Bart M

2016-05-01

CO2 exchange in leaves of maize (Zea mays L.) was examined using a microscale model of combined gas diffusion and C4 photosynthesis kinetics at the leaf tissue level. Based on a generalized scheme of photosynthesis in NADP-malic enzyme type C4 plants, the model accounted for CO2 diffusion in a leaf tissue, CO2 hydration and assimilation in mesophyll cells, CO2 release from decarboxylation of C4 acids, CO2 fixation in bundle sheath cells and CO2 retro-diffusion from bundle sheath cells. The transport equations were solved over a realistic 2-D geometry of the Kranz anatomy obtained from light microscopy images. The predicted responses of photosynthesis rate to changes in ambient CO2 and irradiance compared well with those obtained from gas exchange measurements. A sensitivity analysis showed that the CO2 permeability of the mesophyll-bundle sheath and airspace-mesophyll interfaces strongly affected the rate of photosynthesis and bundle sheath conductance. Carbonic anhydrase influenced the rate of photosynthesis, especially at low intercellular CO2 levels. In addition, the suberin layer at the exposed surface of the bundle sheath cells was found beneficial in reducing the retro-diffusion. The model may serve as a tool to investigate CO2 diffusion further in relation to the Kranz anatomy in C4 plants. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Sequence therapy in metastatic pancreatic cancer.

PubMed

Waidmann, Oliver; Pelzer, Uwe; Boeck, Stefan; Waldschmidt, Dirk-Thomas

2018-06-01

Pancreatic cancer is one of the most lethal cancer diseases. For years, gemcitabine has been the standard of care and the only therapeutic option in patients with metastatic pancreatic cancer. Within the last years, new combination therapies have been established for first-line treatment, which significantly improve overall survival in comparison to gemcitabine monotherapy. Furthermore, new second-line therapies have been identified, which significantly improve overall survival. The current manuscript summarizes briefly standard of care first- and second-line chemotherapies and discusses possible treatment sequences. © Georg Thieme Verlag KG Stuttgart · New York.

Cavitation of intercellular spaces is critical to establishment of hydraulic properties of compression wood of Chamaecyparis obtusa seedlings.

PubMed

Nakaba, Satoshi; Hirai, Asami; Kudo, Kayo; Yamagishi, Yusuke; Yamane, Kenichi; Kuroda, Katsushi; Nugroho, Widyanto Dwi; Kitin, Peter; Funada, Ryo

2016-03-01

When the orientation of the stems of conifers departs from the vertical as a result of environmental influences, conifers form compression wood that results in restoration of verticality. It is well known that intercellular spaces are formed between tracheids in compression wood, but the function of these spaces remains to be clarified. In the present study, we evaluated the impact of these spaces in artificially induced compression wood in Chamaecyparis obtusa seedlings. We monitored the presence or absence of liquid in the intercellular spaces of differentiating xylem by cryo-scanning electron microscopy. In addition, we analysed the relationship between intercellular spaces and the hydraulic properties of the compression wood. Initially, we detected small intercellular spaces with liquid in regions in which the profiles of tracheids were not rounded in transverse surfaces, indicating that the intercellular spaces had originally contained no gases. In the regions where tracheids had formed secondary walls, we found that some intercellular spaces had lost their liquid. Cavitation of intercellular spaces would affect hydraulic conductivity as a consequence of the induction of cavitation in neighbouring tracheids. Our observations suggest that cavitation of intercellular spaces is the critical event that affects not only the functions of intercellular spaces but also the hydraulic properties of compression wood. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The mechanistic basis of internal conductance: a theoretical analysis of mesophyll cell photosynthesis and CO2 diffusion.

PubMed

Tholen, Danny; Zhu, Xin-Guang

2011-05-01

Photosynthesis is limited by the conductance of carbon dioxide (CO(2)) from intercellular spaces to the sites of carboxylation. Although the concept of internal conductance (g(i)) has been known for over 50 years, shortcomings in the theoretical description of this process may have resulted in a limited understanding of the underlying mechanisms. To tackle this issue, we developed a three-dimensional reaction-diffusion model of photosynthesis in a typical C(3) mesophyll cell that includes all major components of the CO(2) diffusion pathway and associated reactions. Using this novel systems model, we systematically and quantitatively examined the mechanisms underlying g(i). Our results identify the resistances of the cell wall and chloroplast envelope as the most significant limitations to photosynthesis. In addition, the concentration of carbonic anhydrase in the stroma may also be limiting for the photosynthetic rate. Our analysis demonstrated that higher levels of photorespiration increase the apparent resistance to CO(2) diffusion, an effect that has thus far been ignored when determining g(i). Finally, we show that outward bicarbonate leakage through the chloroplast envelope could contribute to the observed decrease in g(i) under elevated CO(2). Our analysis suggests that physiological and anatomical features associated with g(i) have been evolutionarily fine-tuned to benefit CO(2) diffusion and photosynthesis. The model presented here provides a novel theoretical framework to further analyze the mechanisms underlying diffusion processes in the mesophyll.

The Mechanistic Basis of Internal Conductance: A Theoretical Analysis of Mesophyll Cell Photosynthesis and CO2 Diffusion1[W][OA

PubMed Central

Tholen, Danny; Zhu, Xin-Guang

2011-01-01

Photosynthesis is limited by the conductance of carbon dioxide (CO2) from intercellular spaces to the sites of carboxylation. Although the concept of internal conductance (gi) has been known for over 50 years, shortcomings in the theoretical description of this process may have resulted in a limited understanding of the underlying mechanisms. To tackle this issue, we developed a three-dimensional reaction-diffusion model of photosynthesis in a typical C3 mesophyll cell that includes all major components of the CO2 diffusion pathway and associated reactions. Using this novel systems model, we systematically and quantitatively examined the mechanisms underlying gi. Our results identify the resistances of the cell wall and chloroplast envelope as the most significant limitations to photosynthesis. In addition, the concentration of carbonic anhydrase in the stroma may also be limiting for the photosynthetic rate. Our analysis demonstrated that higher levels of photorespiration increase the apparent resistance to CO2 diffusion, an effect that has thus far been ignored when determining gi. Finally, we show that outward bicarbonate leakage through the chloroplast envelope could contribute to the observed decrease in gi under elevated CO2. Our analysis suggests that physiological and anatomical features associated with gi have been evolutionarily fine-tuned to benefit CO2 diffusion and photosynthesis. The model presented here provides a novel theoretical framework to further analyze the mechanisms underlying diffusion processes in the mesophyll. PMID:21441385

Electrophysiological and Structural Remodeling in Heart Failure Modulate Arrhythmogenesis. 2D Simulation Study

PubMed Central

Gomez, Juan F.; Cardona, Karen; Martinez, Laura; Saiz, Javier; Trenor, Beatriz

2014-01-01

Background Heart failure is operationally defined as the inability of the heart to maintain blood flow to meet the needs of the body and it is the final common pathway of various cardiac pathologies. Electrophysiological remodeling, intercellular uncoupling and a pro-fibrotic response have been identified as major arrhythmogenic factors in heart failure. Objective In this study we investigate vulnerability to reentry under heart failure conditions by incorporating established electrophysiological and anatomical remodeling using computer simulations. Methods The electrical activity of human transmural ventricular tissue (5 cm×5 cm) was simulated using the human ventricular action potential model Grandi et al. under control and heart failure conditions. The MacCannell et al. model was used to model fibroblast electrical activity, and their electrotonic interactions with myocytes. Selected degrees of diffuse fibrosis and variations in intercellular coupling were considered and the vulnerable window (VW) for reentry was evaluated following cross-field stimulation. Results No reentry was observed in normal conditions or in the presence of HF ionic remodeling. However, defined amount of fibrosis and/or cellular uncoupling were sufficient to elicit reentrant activity. Under conditions where reentry was generated, HF electrophysiological remodeling did not alter the width of the VW. However, intermediate fibrosis and cellular uncoupling significantly widened the VW. In addition, biphasic behavior was observed, as very high fibrotic content or very low tissue conductivity hampered the development of reentry. Detailed phase analysis of reentry dynamics revealed an increase of phase singularities with progressive fibrotic components. Conclusion Structural remodeling is a key factor in the genesis of vulnerability to reentry. A range of intermediate levels of fibrosis and intercellular uncoupling can combine to favor reentrant activity. PMID:25054335

Physicochemical basis for dilated intercellular spaces in non-erosive acid-damaged rabbit esophageal epithelium.

PubMed

Tobey, N A; Gambling, T M; Vanegas, X C; Carson, J L; Orlando, R C

2008-01-01

Dilated intercellular spaces (DIS) within esophageal epithelium (EE) is a histopathologic feature of non-erosive reflux disease and early lesion in acid-damaged rabbit EE associated with increased paracellular permeability. Its cause remains unknown, but the lesion's morphology suggests a significant fluid shift into the intercellular spaces (ICS). Since water follows osmotic forces and consequently ion movements, we explored the role of active (ion) transport and ion gradients in its pathogenesis. This was done by quantifying the effect of inhibited active transport and altered ion gradients on electrical resistance (R(T)) and ICS diameter in acid-exposed Ussing-chambered rabbit EE. Compared with normal Ringer, pH 7.5, 30 minutes of luminal HCl (100 mmol/L), pH 1.1, increased permeability (R(T): +5 +/- 4% vs-52 +/- 4%) and ICS diameter (0.25 +/- 0.01 microm vs 0.42 +/- 0.02 microm), but had no effect on cell morphology or diameter. Ouabain pretreatment significantly reduced active transport but had no effect on the acid-induced changes. However, negating the chloride gradient created by luminal HCl either by adding choline chloride, 100 mmol/L, serosally or by replacing luminal HCl, pH 1.1, with luminal H(2)SO(4), pH 1.1, prevented the development of DIS while maintaining the increase in permeability. DIS was also prevented in the presence of a 100 mmol/L (choline) chloride gradient by luminal exposure at neutral pH. DIS in HCl-damaged EE is caused by an H(+)-induced increase in epithelial permeability; this enables Cl(-) to diffuse along its gradient into the ICS, creating an osmotic force for water movement into and (hydrostatic) dilation of the ICS.

Intercellular nanotubes: insights from imaging studies and beyond

PubMed Central

Hurtig, Johan; Chiu, Daniel T.; Önfelt, Björn

2017-01-01

Cell-cell communication is critical to the development, maintenance, and function of multicellular organisms. Classical mechanisms for intercellular communication include secretion of molecules into the extracellular space and transport of small molecules through gap junctions. Recent reports suggest that cells also can communicate over long distances via a network of transient intercellular nanotubes. Such nanotubes have been shown to mediate intercellular transfer of organelles as well as membrane components and cytoplasmic molecules. Moreover, intercellular nanotubes have been observed in vivo and have been shown to enhance the transmission of pathogens such as human immunodeficiency virus (HIV)-1 and prions in vitro. These studies indicate that intercellular nanotubes may play a role both in normal physiology and in disease. PMID:20166114

Improvement of long-term outcomes in pancreatic cancer and its associated factors within the gemcitabine era: a collaborative retrospective multicenter clinical review of 1,082 patients.

PubMed

Kuroda, Taira; Kumagi, Teru; Yokota, Tomoyuki; Seike, Hirotaka; Nishiyama, Mari; Imai, Yusuke; Inada, Nobu; Shibata, Naozumi; Imamine, Satoshi; Okada, Shin-ichi; Koizumi, Mitsuhito; Yamanishi, Hirofumi; Azemoto, Nobuaki; Miyaike, Jiro; Tanaka, Yoshinori; Tatsukawa, Haruka; Utsunomiya, Hiroki; Ohno, Yoshinori; Miyake, Teruki; Hirooka, Masashi; Furukawa, Shinya; Abe, Masanori; Ikeda, Yoshiou; Matsuura, Bunzo; Hiasa, Yoichi; Onji, Morikazu

2013-08-31

Although the outcomes of pancreatic cancer have been improved by gemcitabine, the changes in its characteristics and long-term outcomes within the gemcitabine era remain unclear. This study was conducted to identify clinical characteristics of pancreatic cancer patients within the gemcitabine era. A retrospective chart review was performed at 10 centers for 1,248 consecutive patients who were ever considered to have a diagnosis of pancreatic cancer between 2001 and 2010. Data collected included demographics, diagnosis date, clinical stage, treatment, and outcome 1,082 patients met the inclusion criteria and were analyzed further. The chi-square test, Student's t-test, and Mann-Whitney U-test were used for statistical analysis. Outcomes were analyzed using the Kaplan-Meier method and Cox proportional hazards regression. Differences in survival analyses were determined using the log-rank test. The distribution of clinical stages was: I, 2.2% II, 3.4% III, 13% IVa, 27% and IVb, 55%. Chemotherapy alone was administered to 42% of patients and 17% underwent resection. The 1-, 3-, and 5-year survival rates were 39%, 13%, and 6.9%, respectively. The median survival time was 257 days, but differed considerably among treatments and clinical stages. Demographics, distribution of clinical stage, and cause of death did not differ between groups A (2001-2005, n=406) and B (2006-2010, n=676). However, group B included more patients who underwent chemotherapy (P<0.0001) and fewer treated with best supportive care (P=0.0004), mirroring improvements in this group's long-term outcomes (P=0.0063). Finally, factors associated with long-term outcomes derived from multivariate analysis were clinical stage (P<0.0001), location of the tumor (P=0.0294) and treatments (surgery, chemotherapy) (<0.0001). Long-term outcomes in pancreatic cancer has improved even within the gemcitabine era, suggesting the importance of offering chemotherapy to patients previously only considered for best supportive care. Most patients are still diagnosed at an advanced stage, making clinical strategy development for diagnosing pancreatic cancer at earlier stages essential.

Induction gemcitabine and oxaliplatin therapy followed by a twice-weekly infusion of gemcitabine and concurrent external-beam radiation for neoadjuvant treatment of locally advanced pancreatic cancer: a single institutional experience.

PubMed

Leone, Francesco; Gatti, Marco; Massucco, Paolo; Colombi, Federica; Sperti, Elisa; Campanella, Delia; Regge, Daniele; Gabriele, Pietro; Capussotti, Lorenzo; Aglietta, Massimo

2013-01-15

Chemoradiotherapy (CRT) may render curative resection feasible in patients with locally advanced pancreatic carcinoma (LAPC). The authors previously demonstrated the achievement of significant disease control and a median survival of 14 months by CRT in patients with LAPC. In this study, they evaluated the use of induction chemotherapy followed by a CRT neoadjuvant protocol. Patients first received induction gemcitabine and oxaliplatin (GEMOX) (gemcitabine 1000 mg/m(2), oxaliplatin 100 mg/m(2)). Patients without disease progression then received gemcitabine twice weekly (50 mg/m(2) daily) concurrent with radiotherapy (50.4 grays) and were re-evaluated for resectability. Thirty-nine patients (15 with borderline resectable disease and 24 with unresectable disease) entered the study. The treatment was well tolerated. Disease control was obtained in 29 of 39 patients. Two patients progressed after GEMOX, and 7 progressed after CRT. After a median follow-up of 13 months, the median progression-free survival (PFS) was 10.2 months. The median PFS of patients with borderline resectable and unresectable disease was 16.6 and 9.1 months, respectively (P = .056). For the whole group, the median overall survival (OS) was 16.7 months (27.8 months for patients with borderline resectable disease, 13.3 for patients with unresectable disease; P = .045). Eleven patients (9 with borderline resectable disease and 2 with unresectable disease at diagnosis) underwent successful resection. Patients who underwent resection had a significantly longer median PFS compared with nonresected patients (19.7 months vs 7.6 months, respectively). The median OS among resected and nonresected patients was 31.5 months and 12.3 months, respectively (P < .001). The current results indicated that induction GEMOX followed by CRT is feasible in patients with LAPC. Both those with borderline resectable disease and those with unresectable disease received clinical benefit, a chance to obtain resectability, and improved survival. The authors concluded that this protocol warrants further evaluation. Copyright © 2012 American Cancer Society.

A PHASE II STUDY OF GEMCITABINE AND CAPECITABINE IN PATIENTS WITH ADVANCED RENAL CELL CANCER (RCC): SOUTHWEST ONCOLOGY GROUP STUDY S0312

PubMed Central

Van Veldhuizen, Peter J.; Hussey, Michael; Lara, Primo N.; Mack, Philip C.; Gandour-Edwards, Regina; Clark, Joseph I.; Lange, Marianne K.; Crawford, E. David

2010-01-01

Background Gemcitabine plus capecitabine has modest efficacy in patients with advanced RCC but has considerable toxicity. We evaluated the efficacy and toxicity of a modified dose-schedule of this doublet in patients with advanced unresectable or metastatic RCC. Methods Chemotherapy-naïve patients were treated with gemcitabine at 900mg/m2 on days 1,8,15 and capecitabine at 625mg/m2 twice daily on days 1 through 21, every 28 days. Eligible patients must have adequate performance status and end-organ function. The primary endpoint was tumor response rate (RR). No further evaluation of this regimen would be pursued if the RR was ≤ 5%. In an exploratory manner using archival specimens, we also evaluated potential markers of prognosis and treatment response including thymidylate synthase (TS) gene polymorphisms and tumor expression of p53, PTEN, pAKT, pmTOR, and ERCC1. Results Of 43 patients registered, 1 was ineligible and 2 were not analyzable. There was 1 confirmed complete response (CR) and three unconfirmed partial responses (PR), for an overall response rate of 10% (95% CI: 3, 24). Nineteen patients (48%) had stable disease (SD). The six-month freedom-from-treatment-failure and overall survival rates were 20% (95% CI: 8, 32) and 75% (95% CI: 62, 88), respectively. Median survival time was 23 months (95% CI: 10, 37). One patient each experienced Grade 4 neutropenia, fatigue, thrombocytopenia and hemolysis with renal failure. The most common Grade 3 toxicities were neutropenia (12 patients), fatigue (5), and leucopenia (4). Patients with a best response of stable disease or better were more likely to have a decrease in expression of PTEN and an increased expression of pmTOR. Conclusions Gemcitabine plus capecitabine at this reduced dose-schedule benefits a small percentage of patients with RCC with an acceptable toxicity profile. The combination of gemcitabine and capecitabine may serve as a base regimen for combination therapy with targeted agents in select RCC patients. PMID:19487915

Cost-effectiveness of gemcitabine in stage IV non-small cell lung cancer: an estimate using the Population Health Model lung cancer module.

PubMed

Evans, W K

1997-04-01

Statistics Canada (Ottawa, Ontario, Canada) is in the process of developing the Population Health Model to simulate the health and common illnesses of Canadians. The Population Health Model incorporates a lung cancer module that is based on contemporary Canadian practice. This microsimulation model can be used to estimate the total direct care costs of treating all lung cancer cases diagnosed in Canada and to evaluate the cost and cost-effectiveness of new therapeutic interventions as they are introduced into practice. Gemcitabine, a new nucleoside analogue with a broad spectrum of antitumor activity, is about to be introduced on the Canadian market. The Population Health Model has been used to estimate the cost-effectiveness of gemcitabine in the management of lung cancer over a range of drug doses per treatment cycle starting at 1,000 mg/m2 weekly x 3, as well as potential survival benefits. The survival of stage IV non-small cell lung cancer (NSCLC) patients treated on an international trial of gemcitabine (EO-18) was used to estimate the potential survival gain relative to the survival of stage IV NSCLC patients managed with best supportive care on a randomized trial conducted by the National Cancer Institute of Canada (BR 5). Sensitivity analyses were performed assuming that the survival gain was 25% or 50% less than that reported in the EO-18 trial. The perspective of the economic analysis is that of the government as payer in a universal health care system, and all costs are expressed in 1993 Canadian dollars. Based on the apparent survival advantage of the EO-18 trial in comparison to best supportive care, the cost per life-year gained ranged from $632 to $9,285, depending on the dose per treatment cycle. At the highest dose per cycle (2,000 mg/m2) and with survival reduced by 50% as compared with the EO-18 result, the cost per life-year gained was estimated to be $17,390. From these estimates of direct care costs in the Canadian health care system, gemcitabine appears to be a cost-effective intervention for advanced NSCLC.

Fixed dose-rate gemcitabine infusion as first-line treatment for advanced-stage carcinoma of the pancreas and biliary tree.

PubMed

Gelibter, Alain; Malaguti, Paola; Di Cosimo, Serena; Bria, Emilio; Ruggeri, Enzo Maria; Carlini, Paolo; Carboni, Fabio; Ettorre, Giuseppe Maria; Pellicciotta, Mario; Giannarelli, Diana; Terzoli, Edmondo; Cognetti, Francesco; Milella, Michele

2005-09-15

Gemcitabine infusion at the fixed dose rate of 10 mg/m(2) per minute (FDR-gemcitabine) has pharmacokinetic advantages and may result in improved therapeutic efficacy. Between April 2002 and September 2003, 40 patients with advanced-stage pancreatic adenocarcinoma (PDAC; n = 27) or biliary tree carcinoma (BTC; n = 13) were treated with weekly FDR-gemcitabine (1000 mg/m(2)). The primary end point was the response rate. The secondary end points were progression-free and overall survival (PFS and OS), tumor marker response, and clinical benefit response (CBR). The overall response rate (ORR) on an intent-to-treat basis was 15% (95% confidence interval [95% CI], 4-26%). A positive CBR was obtained in 14 of 29 (48%) patients. Seventeen of 25 (68%) patients had a reduction in carbohydrate antigen 19-9 (CA 19-9) of > 25%. The median time to treatment failure and the median PFS were 17 weeks (95% CI, 13-22 weeks) and 19 weeks (95% CI, 15-23 weeks), respectively. The median OS was 40 weeks (95% CI, 36-45 weeks) and the 1-year actuarial survival rate was 25.8%. Multivariate analysis showed that a performance status score of 0-1 at study entry and locally advanced disease were the only independent predictors of longer PFS and OS, whereas a reduction in CA 19-9 serum levels > 75% was an independent predictor of longer PFS, but had no impact on OS. Toxicity was mild with Grade 3-4 neutropenia (according to the National Cancer Institute-Common Toxicity Criteria [version 2.0]) in 18 of 427 treatment weeks (4.2%), and Grade 3 anemia and thrombocytopenia in 6 of 427 treatment weeks (1.4%) and 9 of 427 treatment weeks (2.1%), respectively, and asymptomatic Grade 3-4 transaminase elevation in 21 of 427 treatment weeks (4.9%). FDR-gemcitabine at the weekly dose of 1000 mg/m(2) demonstrated promising activity, despite negligible toxicity, in patients with advanced-stage PDAC and BTC. Copyright 2005 American Cancer Society.

Biweekly Carboplatin Plus Gemcitabine as First-Line Treatment of Elderly Patients With Advanced Squamous Non-Small-cell Lung Cancer: A Multicenter Phase I-II Trial by the Hellenic Oncology Research Group.

PubMed

Karampeazis, Athanasios; Vamvakas, Lambros; Kentepozidis, Nikolaos; Polyzos, Aris; Chandrinos, Vassilis; Rigas, Georgios; Christofyllakis, Charalambos; Kotsakis, Athanasios; Hatzidaki, Dora; Pallis, Athanasios G; Georgoulias, Vassilis

2016-11-01

The present study was a phase I/II study to determine the maximum tolerated doses (MTDs) and dose-limiting toxicities of the biweekly carboplatin/gemcitabine combination and evaluate its safety and efficacy in patients aged ≥ 70 years with advanced squamous non-small-cell lung cancer (NSCLC). Patients aged ≥ 70 years with advanced or metastatic squamous NSCLC received escalated doses of carboplatin (area under the curve [AUC] 2-2.5 intravenously) and gemcitabine (800-1100 mg/m 2 intravenously) every 2 weeks (phase I). In the phase II, the drugs were administered at their previously defined MTDs (carboplatin, AUC 2.5; gemcitabine, 1100 mg/m 2 ). The primary endpoint was the overall response rate. A total of 69 patients were enrolled (phase I, n = 15). The median age was 76 years (range, 70-84 years); 52 patients had stage IV disease, and 61 and 8 patients had Eastern Cooperative Oncology Group performance status of 0 to 1 and 2, respectively. The MTDs could not be reached at the predefined last dose levels. The dose-limiting toxicities were grade 5 renal toxicity and grade 3 thrombocytopenia. In the phase II study, the overall response rate was 35.8% (95% confidence interval [CI], 23.0%-48.8%). In the intention-to-treat analysis, the median progression-free survival was 6.7 months (95% CI, 4.2-8.8 months), and the median overall survival was 13.3 months (95% CI, 7.1-19.6 months). Grade 3 or 4 neutropenia was observed in 7 patients (12.3%), grade 3 or 4 thrombocytopenia in 4 patients (7.1%), and grade 2 or 3 fatigue in 10 patients (17.5%). One toxic death occurred in the phase I of the study. The biweekly regimen of gemcitabine and carboplatin showed satisfactory efficacy and a favorable toxicity profile in elderly patients with advanced or metastatic squamous cell NSCLC. Copyright © 2016 Elsevier Inc. All rights reserved.

Berberine induces apoptosis via ROS generation in PANC-1 and MIA-PaCa2 pancreatic cell lines.

PubMed

Park, S H; Sung, J H; Kim, E J; Chung, N

2015-02-01

Pancreatic cancer is the fourth leading cause of cancer death. Gemcitabine is widely used as a chemotherapeutic agent for the treatment of pancreatic cancer, but the prognosis is still poor. Berberine, an isoquinoline alkaloid extracted from a variety of natural herbs, possesses a variety of pharmacological properties including anticancer effects. In this study, we investigated the anticancer effects of berberine and compared its use with that of gemcitabine in the pancreatic cancer cell lines PANC-1 and MIA-PaCa2. Berberine inhibited cell growth in a dose-dependent manner by inducing cell cycle arrest and apoptosis. After berberine treatment, the G1 phase of PANC-1 cells increased by 10% compared to control cells, and the G1 phase of MIA-PaCa2 cells was increased by 2%. Whereas gemcitabine exerts antiproliferation effects through S-phase arrest, our results showed that berberine inhibited proliferation by inducing G1-phase arrest. Berberine-induced apoptosis of PANC-1 and MIA-PaCa2 cells increased by 7 and 2% compared to control cells, respectively. Notably, berberine had a greater apoptotic effect in PANC-1 cells than gemcitabine. Upon treatment of PANC-1 and MIA-PaCa2 with berberine at a half-maximal inhibitory concentration (IC50), apoptosis was induced by a mechanism that involved the production of reactive oxygen species (ROS) rather than caspase 3/7 activation. Our findings showed that berberine had anti-cancer effects and may be an effective drug for pancreatic cancer chemotherapy.

Gemcitabine-Based Combination Chemotherapy Followed by Radiation With Capecitabine as Adjuvant Therapy for Resected Pancreas Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Desai, Sameer; Ben-Josef, Edgar; Griffith, Kent A.

2009-12-01

Purpose: To report outcomes for patients with resected pancreas cancer treated with an adjuvant regimen consisting of gemcitabine-based combination chemotherapy followed by capecitabine and radiation. Patients and Methods: We performed a retrospective review of a series of patients treated at a single institution with a common postoperative adjuvant program. Between January 2002 and August 2006, 43 resected pancreas cancer patients were offered treatment consisting of 4, 21-day cycles of gemcitabine 1 g/m{sup 2} intravenously over 30 min on Days 1 and 8, with either cisplatin 35 mg/m{sup 2} intravenously on Days 1 and 8 or capecitabine 1500 mg/m{sup 2} orallymore » in divided doses on Days 1-14. After completion of combination chemotherapy, patients received a course of radiotherapy (54 Gy) with concurrent capecitabine (1330 mg/m{sup 2} orally in divided doses) day 1 to treatment completion. Results: Forty-one patients were treated. Median progression-free survival for the entire group was 21.7 months (95% confidence interval 13.9-34.5 months), and median overall survival was 45.9 months. In multivariate analysis a postoperative CA 19-9 level of >=180 U/mL predicted relapse and death. Toxicity was mild, with only two hospitalizations during adjuvant therapy. Conclusions: A postoperative adjuvant program using combination chemotherapy with gemcitabine and either cisplatin or capecitabine followed by radiotherapy with capecitabine is tolerable and efficacious and should be considered for Phase III testing in this group of patients.« less

Hypoxia-inducible factor-targeting prodrug TOP3 combined with gemcitabine or TS-1 improves pancreatic cancer survival in an orthotopic model.

PubMed

Hoang, Ngoc Thi Hong; Kadonosono, Tetsuya; Kuchimaru, Takahiro; Kizaka-Kondoh, Shinae

2016-08-01

Pancreatic cancer is one of the most lethal digestive system cancers with a 5-year survival rate of 4-7%. Despite extensive efforts, recent chemotherapeutic regimens have provided only limited benefits to pancreatic cancer patients. Gemcitabine and TS-1, the current standard-of-care chemotherapeutic drugs for treatment of this severe cancer, have a low response rate. Hypoxia is one of the factors contributing to treatment resistance. Specifically, overexpression of hypoxia-inducible factor, a master transcriptional regulator of cell adaption to hypoxia, is strongly correlated with poor prognosis in many human cancers. TAT-ODD-procaspase-3 (TOP3) is a protein prodrug that is specifically processed and activated in hypoxia-inducible factor-active cells in cancers, leading to cell death. Here, we report combination therapies in which TOP3 was combined with gemcitabine or TS-1. As monotherapy, gemcitabine and TS-1 showed a limited effect on hypoxic and starved pancreatic cancer cells, whereas co-treatment with TOP3 successfully overcame this limitation in vitro. Furthermore, combination therapies of TOP3 with these drugs resulted in a significant improvement in survival of orthotopic pancreatic cancer models involving the human pancreatic cancer cell line SUIT-2. Overall, our study indicates that the combination of TOP3 with current chemotherapeutic drugs can significantly improve treatment outcome, offering a promising new therapeutic option for patients with pancreatic cancer. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Design and evaluation of an intravesical delivery system for superficial bladder cancer: preparation of gemcitabine HCl-loaded chitosan–thioglycolic acid nanoparticles and comparison of chitosan/poloxamer gels as carriers

PubMed Central

Ay Şenyiğit, Zeynep; Karavana, Sinem Yaprak; İlem-Özdemir, Derya; Çalışkan, Çağrı; Waldner, Claudia; Şen, Sait; Bernkop-Schnürch, Andreas; Baloğlu, Esra

2015-01-01

This study aimed to develop an intravesical delivery system of gemcitabine HCl for superficial bladder cancer in order to provide a controlled release profile, to prolong the residence time, and to avoid drug elimination via urination. For this aim, bioadhesive nanoparticles were prepared with thiolated chitosan (chitosan–thioglycolic acid conjugate) and were dispersed in bioadhesive chitosan gel or in an in situ gelling poloxamer formulation in order to improve intravesical residence time. In addition, nanoparticle-loaded gels were diluted with artificial urine to mimic in vivo conditions in the bladder and were characterized regarding changes in gel structure. The obtained results showed that chitosanthioglycolic acid nanoparticles with a mean diameter of 174.5±3.762 nm and zeta potential of 32.100±0.575 mV were successfully developed via ionotropic gelation and that the encapsulation efficiency of gemcitabine HCl was nearly 20%. In vitro/ex vivo characterization studies demonstrated that both nanoparticles and nanoparticle-loaded chitosan and poloxamer gels might be alternative carriers for intravesical administration of gemcitabine HCl, prolonging its residence time in the bladder and hence improving treatment efficacy. However, when the gel formulations were diluted with artificial urine, poloxamer gels lost their in situ gelling properties at body temperature, which is in conflict with the aimed formulation property. Therefore, 2% chitosan gel formulation was found to be a more promising carrier system for intravesical administration of nanoparticles. PMID:26508855

Cost-effectiveness analysis of gemcitabine, S-1 and gemcitabine plus S-1 for treatment of advanced pancreatic cancer based on GEST study.

PubMed

Zhou, Jing; Zhao, Rongce; Wen, Feng; Zhang, Pengfei; Tang, Ruilei; Du, Zedong; He, Xiaofeng; Zhang, Jian; Li, Qiu

2015-04-01

Gemcitabine (GEM) alone, S-1 alone and gemcitabine plus S-1 (GS) have shown a marginal clinical benefit for the treatment of advanced pancreatic cancer. However, there is no clearly defined optimal cost-effectiveness treatment. The objective of this study was to assess the cost-effectiveness of GEM alone, S-1 alone and GS for the treatment of advanced pancreatic cancer based on GEST study for public payers. A decision model compared GEM alone, S-1 alone and GS. Primary base case data were identified using the GEST study and the literatures. Costs were estimated from West China Hospital, Sichuan University, China, and incremental cost-effectiveness ratios (ICERs) were calculated. Survival benefits were reported in quality-adjusted life-months (QALMs). Sensitive analyses were performed by varying potentially modifiable parameters of the model. The base case analysis showed that the GEM cost $21,912 and yielded survival of 6.93 QALMs, S-1 cost $19,371 and yielded survival of 7.90 QALMs and GS cost $22,943 and yielded survival of 7.46 QALMs in the entire treatment. The one-way sensitivity analyses showed that the ICER of S-1 was driven mostly by the S-1 group utility score of stable state compared with GEM, and the GEM group utility score of progressed state played a key role on the ICER of GS compared with GEM. S-1 represents an attractive cost-effective treatment for advanced pancreatic cancer, given the favorable cost per QALM and improvement in clinical efficacy, especially the limited available treatment options.

Intravenous ω-3 Fatty Acids Plus Gemcitabine.

PubMed

Arshad, Ali; Isherwood, John; Mann, Christopher; Cooke, Jill; Pollard, Cristina; Runau, Franscois; Morgan, Bruno; Steward, William; Metcalfe, Matthew; Dennison, Ashley

2017-03-01

Marine-derived ω-3 fatty acids (ω-3FAs) have proven antitumor activity in vivo and in vitro and improve quality of life (QOL) in clinical cancer studies. These changes may be mediated by reduction in circulating proangiogenic and proinflammatory factors. In this first study of intravenous ω-3FAs as a therapy in cancer patients, we aimed to assess if it could augment the antitumor activity of gemcitabine in patients with advanced pancreatic cancer and improve QOL. Patients were administered gemcitabine 1000 mg/m 3 weekly followed by up to 100 g (200 mg/mL) of ω-3 rich lipid emulsion for 3 weeks followed by a rest week. This was continued for up to 6 cycles, progression, unacceptable toxicity, patient request, or death. The primary outcome measure was objective response rate, with secondary outcome measures of overall and progression free survival, QOL scores, and adverse events. Fifty patients were recruited. Response rate was 14.3% and disease control rate was 85.7%. Overall and progression free survival were 5.9 and 4.8 months, respectively. Increase in global health of > 10% over baseline was seen in 47.2% of patients. More than 50% of patients had > 10% increase in QOL scores in generic symptom scores and both disease-specific domains. Grade 3/4 adverse events were thrombocytopenia (8%), neutropenia (12%), nausea or vomiting (4%), and chills (6%). Intravenous ω-3FAs in combination with gemcitabine shows evidence of improved activity and benefit to QOL in patients with advanced pancreas cancer and is worthy of investigation in a randomized phase III trial.

Zyflamend Suppresses Growth and Sensitizes Human Pancreatic Tumors to Gemcitabine in an Orthotopic Mouse Model Through Modulation of Multiple Targets

PubMed Central

Kunnumakkara, Ajaikumar B.; Sung, Bokyung; Ravindran, Jayaraj; Diagaradjane, Parmeswaran; Deorukhkar, Amit; Dey, Sanjit; Koca, Cemile; Tong, Zhimin; Gelovani, Juri G.; Guha, Sushovan; Krishnan, Sunil; Aggarwal, Bharat B.

2011-01-01

Agents that can potentiate the efficacy of standard chemotherapy against pancreatic cancer are of great interest. Because of their low cost and safety, patients commonly use a variety of dietary supplements, although evidence of their efficacy is often lacking. One such commonly used food supplement, Zyflamend, is a polyherbal preparation with potent anti-inflammatory activities, and preclinical efficacy against prostate and oral cancer. Whether Zyflamend has any efficacy against human pancreatic cancer alone or in combination with gemcitibine, a commonly used agent, was examined in cell cultures and in an orthotopic mouse model. In vitro, Zyflamend inhibited the proliferation of pancreatic cancer cell lines regardless of p53 status and also enhanced gemcitabine-induced apoptosis. This finding correlated with inhibition of NF-κB activation by Zyflamend and suppression of cyclin D1, c-myc, COX-2, Bcl-2, IAP, survivin, VEGF, ICAM-1, and CXCR4. In nude mice, oral administration of Zyflamend alone significantly inhibited the growth of orthotopically transplanted human pancreatic tumors, and when combined with gemcitabine, further enhanced the antitumor effects. Immunohistochemical and Western blot analyses of tumor tissue showed that the suppression of pancreatic cancer growth correlated with inhibition of proliferation index marker (Ki-67), COX-2, MMP-9, NF-κB, and VEGF. Overall, these results suggest that the concentrated multiherb product Zyflamend alone can inhibit the growth of human pancreatic tumors and, in addition, can sensitize pancreatic cancers to gemcitabine through the suppression of multiple targets linked to tumorigenesis. PMID:21935918

High-Dose Infusional Gemcitabine Combined with Busulfan and Melphalan with Autologous Stem-Cell Transplant in Patients with Refractory Lymphoid Malignancies

PubMed Central

Nieto, Y; Thall, P; Valdez, B; Andersson, B; Popat, U; Anderlini, P; Shpall, EJ; Bassett, R; Alousi, A; Hosing, C; Kebriaei, P; Qazilbash, M; Gulbis, A; Chancoco, C; Bashir, Q; Ciurea, S; Khouri, I; Parmar, S; Shah, N; Worth, L; Rondon, G; Champlin, R; Jones, RB

2014-01-01

We developed a new high-dose combination of infusional gemcitabine with busulfan/melphalan for lymphoid tumors. Gemcitabine dose was escalated by extending infusions at a fixed rate of 10 mg/m2/min in sequential cohorts, in daily, 3-dose or 2-dose schedules. Each dose immediately preceded busulfan (adjusted targeting AUC 4,000 μM.min−1/day × 4 days) or melphalan (60 mg/m2/day × 2 days). We enrolled 133 patients (80 Hodgkin’s lymphoma (HL), 46 non-Hodgkin’s lymphoma (NHL), 7 myeloma), median 3 prior regimens; primary refractory disease in 63% HL/45% NHL and PET-positive tumors at transplant in 50% patients. Two patients died from early posttransplant infections. The major toxicity was mucositis. The daily and 3-dose schedules caused substantial cutaneous toxicity. In contrast, the 2-dose schedule was better tolerated, which allowed us to extend the infusions from 15 to 270 minutes. Pretransplant values of C-reactive protein, b-type natriuretic peptide, ferritin or haptoglobin did not correlate with toxicity. Overall response and complete response rates were 87%/62% (HL), 100%/69% (B-LCL), 66%/66% (T-NHL), and 71%/57% (myeloma). At median follow-up of 24 months (3–63), the event-free/overall survival rates are 54%/72% (HL), 60%/89% (B-LCL), 70%/70% (T-NHL) and 43%/43% (myeloma). In conclusion, gemcitabine/busulfan/melphalan is a feasible regimen with substantial activity against a range of lymphoid malignancies. This regimen merits further evaluation in phase II and III trials. PMID:22643322

Cisplatin, Gemcitabine, and Lapatinib as Neoadjuvant Therapy for Muscle-Invasive Bladder Cancer.

PubMed

Narayan, Vivek; Mamtani, Ronac; Keefe, Stephen; Guzzo, Thomas; Malkowicz, S Bruce; Vaughn, David J

2016-07-01

We sought to investigate the safety and efficacy of gemcitabine, cisplatin, and lapatinib (GCL) as neoadjuvant therapy in patients with muscle-invasive bladder cancer (MIBC) planned for radical cystectomy. Four cycles of GCL were administered as neoadjuvant therapy for patients with MIBC. Although initially designed as a phase II efficacy study with a primary endpoint of pathologic complete response at the time of radical cystectomy, the dose selected for investigation proved excessively toxic. A total of six patients were enrolled. The initial four patients received gemcitabine 1,000 mg/m(2) intravenously on days 1 and 8 and cisplatin 70 mg/m(2) intravenously on day 1 of each 21-day treatment cycle. Lapatinib was administered as 1,000 mg orally daily starting one week prior to the initiation of cycle 1 of gemcitabine and cisplatin (GC) and continuing until the completion of cycle 4 of GC. These initial doses were poorly tolerated, and the final two enrolled patients received a reduced lapatinib dose of 750 mg orally daily. However, reduction of the lapatinib dose did not result in improved tolerance or drug-delivery, and the trial was terminated early due to excessive toxicity. Grade 3/4 toxicities included diarrhea (33%), nausea/vomiting (33%), and thrombocytopenia (33%). The addition of lapatinib to GC as neoadjuvant therapy for MIBC was limited by excessive treatment-related toxicity. These findings highlight the importance of thorough dose-escalation investigation of combination therapies prior to evaluation in the neoadjuvant setting, as well as the limitations of determination of maximum tolerated dose for novel targeted combination regimens.

Localized delivery of chemotherapy to the cervix for radiosensitization.

PubMed

Hodge, Lucy S; Downs, Levi S; Chura, Justin C; Thomas, Sajeena G; Callery, Patrick S; Soisson, A Patrick; Kramer, Paul; Wolfe, Stephen S; Tracy, Timothy S

2012-10-01

Chemoradiation is the mainstay of therapy for advanced cervical cancer, with the most effective treatment regimens involving combinations of radiosensitizing agents. However, administration of radiosensitizing chemotherapeutics concurrently with pelvic radiation is not without side effects. The aim of this study was to examine the utility of localized drug delivery as a means of improving drug targeting of radiosensitizing chemotherapeutics to the cervix while limiting systemic toxicities. An initial proof-of-concept study was performed in 14 healthy women following local administration of diazepam utilizing a novel cervical delivery device (CerviPrep™). Uterine vein and peripheral blood samples were collected and diazepam was measured using a GC-MS method. In the follow-up study, gemcitabine was applied to the cervix in 17 women undergoing hysterectomy for various gynecological malignancies. Cervical tissue, uterine vein blood samples, and peripheral plasma were collected, and gemcitabine and its deaminated metabolite 2',2'-difluorodeoxyuridine (dFdU) were measured using HPLC-UV and LC/MS methods. Targeted delivery of diazepam to the cervix was consistent with parent drug detectable in the uterine vein of 13 of 14 women. In the second study, pharmacologically relevant concentrations of gemcitabine (0.01-6.6 nmol/g tissue) were detected in the cervical tissue of 11 of 16 available specimens with dFdU measureable in 15 samples (0.04-8.8 nmol/g tissue). Neither gemcitabine nor its metabolites were detected in the peripheral plasma of any subject. Localized drug delivery to the cervix is possible and may be useful in limiting toxicity associated with intravenous administration of chemotherapeutics for radiosensitization. Copyright © 2012 Elsevier Inc. All rights reserved.

Vitamin E δ-Tocotrienol Augments the Anti-tumor Activity of Gemcitabine and Suppresses Constitutive NF-κB Activation in Pancreatic Cancer

PubMed Central

Husain, Kazim; Francois, Rony A.; Yamauchi, Teruo; Perez, Marta; Sebti, Said M.; Malafa, Mokenge P.

2011-01-01

The nuclear factor-κB (NF-κB) transcription factor functions as a crucial regulator of cell survival and chemoresistance in pancreatic cancer. Recent studies suggest that tocotrienols, which are the unsaturated forms of vitamin E, are a promising class of anti-cancer compounds that inhibit the growth and survival of many cancer cells, including pancreatic cancer. Here, we show that tocotrienols inhibited NF-κB activity and the survival of human pancreatic cancer cells in vitro and in vivo. Importantly, we found the bioactivity of the 4 natural tocotrienol compounds (α-, β-, δ-, and γ-tocotrienol) to be directly related to their ability to suppress NF-κB activity in vitro and in vivo. The most bioactive tocotrienol for pancreatic cancer, δ-tocotrienol, significantly enhanced the efficacy of gemcitabine to inhibit pancreatic cancer growth and survival in vitro and in vivo. Moreover, we found that δ-tocotrienol augmentation of gemcitabine activity in pancreatic cancer cells and tumors is associated with significant suppression of NF-κB activity and the expression of NF-κB transcriptional targets [Bcl-XL, X-linked inhibitor of apoptosis (XIAP), and survivin]. Our study represents the first comprehensive pre-clinical evaluation of the activity of natural vitamin E compounds in pancreatic cancer. Given these results, we are conducting a phase I trial of δ-tocotrienol in patients with pancreatic cancer utilizing pancreatic tumor cell survival and NF-κB signaling components as intermediate biomarkers. Our data also support future clinical investigation of δ-tocotrienol to augment gemcitabine activity in pancreatic cancer. PMID:21971120

Suppression of Reserve MCM Complexes Chemosensitizes to Gemcitabine and 5-Fluorouracil

PubMed Central

Bryant, Victoria L.; Elias, Roy M.; McCarthy, Susan M.; Yeatman, Timothy J.; Alexandrow, Mark G.

2015-01-01

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest forms of cancer and is very difficult to treat with conventional chemotherapeutic regimens. Gemcitabine and 5-fluorouracil (5-FU) are used in the management of PDAC and act by indirectly blocking replicative forks. However, these drugs are not highly effective at suppressing disease progression, indicating a need for the development of innovative therapeutic approaches. Recent studies indicate that suppression of the MCM helicase may provide a novel means to sensitize cancer cells to chemotherapeutic agents that inhibit replicative fork progression. Mammalian cells assemble more MCM complexes on DNA than are required to start S-phase. The excess MCM complexes function as back-up initiation sites under conditions of replicative stress. The current study provides definitive evidence that co-suppression of the excess/back-up MCM complexes sensitizes PDAC tumor lines to both gemcitabine and 5-FU, leading to increased loss of proliferative capacity compared to drugs alone. This occurs because reduced MCM levels prevent efficient recovery of DNA replication in tumor cells exposed to drug. PDAC tumor cells are more sensitive to MCM loss in the presence of gemcitabine than are non-tumor, immortalized epithelial cells. Similarly, colon tumor cells are rendered less viable when co-suppression of MCM complexes occurs during exposure to the crosslinking agent oxaliplatin or topoisomerase inhibitor etoposide. Implications These studies demonstrate that suppressing the back-up complement of MCM complexes provides an effective sensitizing approach with the potential to increase the therapeutic index of drugs used in the clinical management of PDAC and other cancers. PMID:26063742

Suppression of Reserve MCM Complexes Chemosensitizes to Gemcitabine and 5-Fluorouracil.

PubMed

Bryant, Victoria L; Elias, Roy M; McCarthy, Susan M; Yeatman, Timothy J; Alexandrow, Mark G

2015-09-01

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest forms of cancer and is very difficult to treat with conventional chemotherapeutic regimens. Gemcitabine and 5-fluorouracil are used in the management of PDAC and act by indirectly blocking replicative forks. However, these drugs are not highly effective at suppressing disease progression, indicating a need for the development of innovative therapeutic approaches. Recent studies indicate that suppression of the MCM helicase may provide a novel means to sensitize cancer cells to chemotherapeutic agents that inhibit replicative fork progression. Mammalian cells assemble more MCM complexes on DNA than are required to start S-phase. The excess MCM complexes function as backup initiation sites under conditions of replicative stress. The current study provides definitive evidence that cosuppression of the excess/backup MCM complexes sensitizes PDAC tumor lines to both gemcitabine and 5-FU, leading to increased loss of proliferative capacity compared with drugs alone. This occurs because reduced MCM levels prevent efficient recovery of DNA replication in tumor cells exposed to drug. PDAC tumor cells are more sensitive to MCM loss in the presence of gemcitabine than are nontumor, immortalized epithelial cells. Similarly, colon tumor cells are rendered less viable when cosuppression of MCM complexes occurs during exposure to the crosslinking agent oxaliplatin or topoisomerase inhibitor etoposide. These studies demonstrate that suppressing the backup complement of MCM complexes provides an effective sensitizing approach with the potential to increase the therapeutic index of drugs used in the clinical management of PDAC and other cancers. ©2015 American Association for Cancer Research.

CG200745, an HDAC inhibitor, induces anti-tumour effects in cholangiocarcinoma cell lines via miRNAs targeting the Hippo pathway.

PubMed

Jung, Dawoon E; Park, Soo Been; Kim, Kahee; Kim, Chanyang; Song, Si Young

2017-09-07

Cholangiocarcinoma is a devastating malignancy with fatal complications that exhibits low response and resistance to chemotherapy. Here, we evaluated the anticancer effects of CG200745, a novel histone deacetylase inhibitor, either alone or in combination with standard chemotherapy drugs in cholangiocarcinoma cells. CG200745 dose-dependently reduced the viability of cholangiocarcinoma cells in vitro and decreased tumour volume and weight in a xenograft model. Administering CG200745 along with other chemotherapeutic agents including gemcitabine, 5-fluorouracil (5-FU), cisplatin, oxaliplatin, or gemcitabine plus cisplatin further decreased cholangiocarcinoma cell viability, with a combination index < 1 that indicated synergistic action. CG200745 also enhanced the sensitivity of gemcitabine-resistant cells to gemcitabine and 5-FU, thereby decreasing cell viability and inducing apoptosis. This was accompanied by downregulation of YAP, TEAD4, TGF-β2, SMAD3, NOTCH3, HES5, Axl, and Gas6 and upregulation of the miRNAs miR-22-3p, miR-22-5p, miR-194-5p, miR-194-3p, miR-194-5p, miR-210-3p, and miR-509-3p. The Ingenuity Pathway Analysis revealed that CG200745 mainly targets the Hippo signalling pathway by inducing miR-509-3p expression. Thus, CG200745 inhibits cholangiocarcinoma growth in vitro and in vivo, and acts synergistically when administered in combination with standard chemotherapeutic agents, enabling dose reduction. CG200745 is therefore expected to improve the outcome of cholangiocarcinoma patients who exhibit resistance to conventional therapies.

Reduction of Decoy Receptor 3 Enhances TRAIL-Mediated Apoptosis in Pancreatic Cancer

PubMed Central

Wang, Wei; Yang, Shanmin; Su, Ying; Zhang, Hengshan; Liu, Chaomei; Li, Xinfeng; Lin, Ling; Kim, Sunghee; Okunieff, Paul; Zhang, Zhenhuan; Zhang, Lurong

2013-01-01

Most human pancreatic cancer cells are resistant to tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis. However, the mechanisms by which pancreatic cancer cells utilize their extracellular molecules to counteract the proapoptotic signaling mediated by the TNF family are largely unknown. In this study, we demonstrate for the first time that DcR3, a secreted decoy receptor that malignant pancreatic cancer cells express at a high level, acts as an extracellular antiapoptotic molecule by binding to TRAIL and counteracting its death-promoting function. The reduction of DcR3 with siRNA unmasked TRAIL and greatly enhanced TRAIL-induced apoptosis. Gemcitabine, a first-line drug for pancreatic cancer, also reduced the level of DcR3. The addition of DcR3 siRNA further enhanced gemcitabine-induced apoptosis. Notably, our in vivo study demonstrated that the therapeutic effect of gemcitabine could be enhanced via further reduction of DcR3, suggesting that downregulation of DcR3 in tumor cells could tip the balance of pancreatic cells towards apoptosis and potentially serve as a new strategy for pancreatic cancer therapy. PMID:24204567

Let-7 Sensitizes KRAS Mutant Tumor Cells to Chemotherapy

PubMed Central

Dai, Xin; Jiang, Ying; Tan, Chalet

2015-01-01

KRAS is the most commonly mutated oncogene in human cancers and is associated with poor prognosis and drug resistance. Let-7 is a family of tumor suppressor microRNAs that are frequently suppressed in solid tumors, where KRAS mutations are highly prevalent. In this study, we investigated the potential use of let-7 as a chemosensitizer. We found that let-7b repletion selectively sensitized KRAS mutant tumor cells to the cytotoxicity of paclitaxel and gemcitabine. Transfection of let-7b mimic downregulated the expression of mutant but not wild-type KRAS. Combination of let-7b mimic with paclitaxel or gemcitabine diminished MEK/ERK and PI3K/AKT signaling concurrently, triggered the onset of apoptosis, and reverted the epithelial-mesenchymal transition in KRAS mutant tumor cells. In addition, let-7b repletion downregulated the expression of β-tubulin III and ribonucleotide reductase subunit M2, two proteins known to mediate tumor resistance to paclitaxel and gemcitabine, respectively. Let-7 may represent a new class of chemosensitizer for the treatment of KRAS mutant tumors. PMID:25946136

Effects of a non thermal plasma treatment alone or in combination with gemcitabine in a MIA PaCa2-luc orthotopic pancreatic carcinoma model.

PubMed

Brullé, Laura; Vandamme, Marc; Riès, Delphine; Martel, Eric; Robert, Eric; Lerondel, Stéphanie; Trichet, Valérie; Richard, Serge; Pouvesle, Jean-Michel; Le Pape, Alain

2012-01-01

Pancreatic tumors are the gastrointestinal cancer with the worst prognosis in humans and with a survival rate of 5% at 5 years. Nowadays, no chemotherapy has demonstrated efficacy in terms of survival for this cancer. Previous study focused on the development of a new therapy by non thermal plasma showed significant effects on tumor growth for colorectal carcinoma and glioblastoma. To allow targeted treatment, a fibered plasma (Plasma Gun) was developed and its evaluation was performed on an orthotopic mouse model of human pancreatic carcinoma using a MIA PaCa2-luc bioluminescent cell line. The aim of this study was to characterize this pancreatic carcinoma model and to determine the effects of Plasma Gun alone or in combination with gemcitabine. During a 36 days period, quantitative BLI could be used to follow the tumor progression and we demonstrated that plasma gun induced an inhibition of MIA PaCa2-luc cells proliferation in vitro and in vivo and that this effect could be improved by association with gemcitabine possibly thanks to its radiosensitizing properties.

Reduction of decoy receptor 3 enhances TRAIL-mediated apoptosis in pancreatic cancer.

PubMed

Wang, Wei; Zhang, Mei; Sun, Weimin; Yang, Shanmin; Su, Ying; Zhang, Hengshan; Liu, Chaomei; Li, Xinfeng; Lin, Ling; Kim, Sunghee; Okunieff, Paul; Zhang, Zhenhuan; Zhang, Lurong

2013-01-01

Most human pancreatic cancer cells are resistant to tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis. However, the mechanisms by which pancreatic cancer cells utilize their extracellular molecules to counteract the proapoptotic signaling mediated by the TNF family are largely unknown. In this study, we demonstrate for the first time that DcR3, a secreted decoy receptor that malignant pancreatic cancer cells express at a high level, acts as an extracellular antiapoptotic molecule by binding to TRAIL and counteracting its death-promoting function. The reduction of DcR3 with siRNA unmasked TRAIL and greatly enhanced TRAIL-induced apoptosis. Gemcitabine, a first-line drug for pancreatic cancer, also reduced the level of DcR3. The addition of DcR3 siRNA further enhanced gemcitabine-induced apoptosis. Notably, our in vivo study demonstrated that the therapeutic effect of gemcitabine could be enhanced via further reduction of DcR3, suggesting that downregulation of DcR3 in tumor cells could tip the balance of pancreatic cells towards apoptosis and potentially serve as a new strategy for pancreatic cancer therapy.

A Sterile 20 Family Kinase and Its Co-factor CCM-3 Regulate Contractile Ring Proteins on Germline Intercellular Bridges.

PubMed

Rehain-Bell, Kathryn; Love, Andrew; Werner, Michael E; MacLeod, Ian; Yates, John R; Maddox, Amy Shaub

2017-03-20

Germ cells in most animals are connected by intercellular bridges, actin-based rings that form stable cytoplasmic connections between cells promoting communication and coordination [1]. Moreover, these connections are required for fertility [1, 2]. Intercellular bridges are proposed to arise from stabilization of the cytokinetic ring during incomplete cytokinesis [1]. Paradoxically, proteins that promote closure of cytokinetic rings are enriched on stably open intercellular bridges [1, 3, 4]. Given this inconsistency, the mechanism of intercellular bridge stabilization is unclear. Here, we used the C. elegans germline as a model for identifying molecular mechanisms regulating intercellular bridges. We report that bridges are actually highly dynamic, changing size at precise times during germ cell development. We focused on the regulation of bridge stability by anillins, key regulators of cytokinetic rings and cytoplasmic bridges [1, 4-7]. We identified GCK-1, a conserved serine/threonine kinase [8], as a putative novel anillin interactor. GCK-1 works together with CCM-3, a known binding partner [9], to promote intercellular bridge stability and limit localization of both canonical anillin and non-muscle myosin II (NMM-II) to intercellular bridges. Additionally, we found that a shorter anillin, known to stabilize bridges [4, 7], also regulates NMM-II levels at bridges. Consistent with these results, negative regulators of NMM-II stabilize intercellular bridges in the Drosophila egg chamber [10, 11]. Together with our findings, this suggests that tuning of myosin levels is a conserved mechanism for the stabilization of intercellular bridges that can occur by diverse molecular mechanisms. Copyright © 2017 Elsevier Ltd. All rights reserved.

A phase I, dose-finding study of sorafenib in combination with gemcitabine and radiation therapy in patients with unresectable pancreatic adenocarcinoma: a Grupo Español Multidisciplinario en Cáncer Digestivo (GEMCAD) study.

PubMed

Aparicio, Jorge; García-Mora, Carmen; Martín, Marta; Petriz, Ma Lourdes; Feliu, Jaime; Sánchez-Santos, Ma Elena; Ayuso, Juan Ramón; Fuster, David; Conill, Carlos; Maurel, Joan

2014-01-01

Sorafenib, an oral inhibitor of B-raf, VEGFR2, and PDGFR2-beta, acts against pancreatic cancer in preclinical models. Due to the radio-sensitization activity of both sorafenib and gemcitabine, we designed a multicenter, phase I trial to evaluate the safety profile and the recommended dose of this combination used with concomitant radiation therapy. Patients with biopsy-proven, unresectable pancreatic adenocarcinoma (based on vascular invasion detected by computed tomography) were treated with gemcitabine (300 mg/m2 i.v. weekly ×5 weeks) concurrently with radiation therapy (45 Gy in 25 fractions) and sorafenib (escalated doses in a 3+3 design, from 200 to 800 mg/day). Radiation portals included the primary tumor but not the regional lymph nodes. Patients with planning target volumes (PTV) over 500 cc were excluded. Cases not progressing during chemoradiation were allowed to continue with sorafenib until disease progression. Twelve patients were included. Three patients received 200 mg/day, 6 received 400 mg/day, and 3 received 800 mg/day; PTVs ranged from 105 to 500 cc. No dose-limiting toxicities occurred. The most common grade 2 toxicities were fatigue, neutropenia, nausea, and raised serum transaminases. Treatment was discontinued in one patient because of a reversible posterior leukoencephalopathy. There were no treatment-related deaths. The addition of sorafenib to concurrent gemcitabine and radiation therapy showed a favorable safety profile in unresectable pancreatic adenocarcinoma. A dose of 800 mg/day is recommended for phase II evaluation. EudraCT 2007-003211-31 ClinicalTrials.gov 00789763.

Modeling targeted inhibition of MEK and PI3 kinase in human pancreatic cancer.

PubMed

Junttila, Melissa R; Devasthali, Vidusha; Cheng, Jason H; Castillo, Joseph; Metcalfe, Ciara; Clermont, Anne C; Otter, Douglas Den; Chan, Emily; Bou-Reslan, Hani; Cao, Tim; Forrest, William; Nannini, Michelle A; French, Dorothy; Carano, Richard; Merchant, Mark; Hoeflich, Klaus P; Singh, Mallika

2015-01-01

Activating mutations in the KRAS oncogene occur in approximately 90% of pancreatic cancers, resulting in aberrant activation of the MAPK and the PI3K pathways, driving malignant progression. Significant efforts to develop targeted inhibitors of nodes within these pathways are underway and several are currently in clinical trials for patients with KRAS-mutant tumors, including patients with pancreatic cancer. To model MEK and PI3K inhibition in late-stage pancreatic cancer, we conducted preclinical trials with a mutant Kras-driven genetically engineered mouse model that faithfully recapitulates human pancreatic ductal adenocarcinoma development. Treatment of advanced disease with either a MEK (GDC-0973) or PI3K inhibitor (GDC-0941) alone showed modest tumor growth inhibition and did not significantly enhance overall survival. However, combination of the two agents resulted in a significant survival advantage as compared with control tumor-bearing mice. To model the clinical scenario, we also evaluated the combination of these targeted agents with gemcitabine, the current standard-of-care chemotherapy for pancreatic cancer. The addition of MEK or PI3K inhibition to gemcitabine, or the triple combination regimen, incrementally enhanced overall survival as compared with gemcitabine alone. These results are reminiscent of the survival advantage conferred in this model and in patients by the combination of gemcitabine and erlotinib, an approved therapeutic regimen for advanced nonresectable pancreatic cancer. Taken together, these data indicate that inhibition of MEK and PI3K alone or in combination with chemotherapy do not confer a dramatic improvement as compared with currently available therapies for patients with pancreatic cancer. ©2014 American Association for Cancer Research.

Eligibility of Metastatic Pancreatic Cancer Patients for First-Line Palliative Intent nab-Paclitaxel Plus Gemcitabine Versus FOLFIRINOX.

PubMed

Peixoto, Renata D; Ho, Maria; Renouf, Daniel J; Lim, Howard J; Gill, Sharlene; Ruan, Jenny Y; Cheung, Winson Y

2017-10-01

The PRODIGE and MPACT trials showed superiority of FOLFIRINOX and nab-paclitaxel plus gemcitabine (NG) over gemcitabine alone, respectively. However, both had strict inclusion criteria. We sought to determine the characteristics of patients with metastatic pancreatic cancer (MPC) which inform the appropriateness of first-line chemotherapy FOLFIRINOX and NG in routine practice. Patients with MPC who initiated palliative chemotherapy with gemcitabine from 2000 to 2011 at the British Columbia Cancer Agency were identified. Clinicopathologic variables and outcomes were retrospectively collected and compared among groups. Eligibility criteria for each regimen were in accordance with the respective pivotal phase III trials. A total of 473 patients were included: 25% of the patients were eligible for FOLFIRINOX versus 45% for NG. Main reasons for FOLFIRINOX ineligibility were Eastern Cooperative Oncology Group (ECOG) performance status (PS)≥2 (56.5%), age older than 75 years (19.0%), and bilirubin>1.5× upper limit of normal (18.6%), whereas those for NG ineligibility were bilirubin > upper limit of normal (24.5%), ECOG PS≥3 (14.6%), and cardiac dysfunction (13.8%). Univariate analyses revealed that FOLFIRINOX and NG-eligible patients had longer median overall survival than their respective ineligible group (8.6 vs. 4.7 mo, P<0.001; 6.7 vs. 4.9 mo, P=0.008, respectively). After accounting for ECOG PS in the multivariate model, however, eligibility for either FOLFIRINOX or NG no longer predicted for better overall survival. The majority of patients with MPC are not candidates to either NG or FOLFIRINOX due to restrictive eligibility requirements. Specific trials addressing the unmet needs of protocol ineligible patients are warranted.

Analysis of Predictors of Resection and Survival in Locally Advanced Stage III Pancreatic Cancer: Does the Nature of Chemotherapy Regimen Influence Outcomes?

PubMed

Bednar, Filip; Zenati, Mazen S; Steve, Jennifer; Winters, Sharon; Ocuin, Lee M; Bahary, Nathan; Hogg, Melissa E; Zeh, Herbert J; Zureikat, Amer H

2017-05-01

Locally advanced unresectable pancreatic cancer (LAPC) historically portends a poor prognosis. FOLFIRINOX and gemcitabine/nab-paclitaxel have proven effective in the metastatic setting. We sought to evaluate the outcomes of these regimens compared with older regimens in LAPC. A retrospective, single institutional review of all consecutive LAPC treated with "new" (FOLFIRINOX and/or gemcitabine/nab-paclitaxel) and "old" (gemcitabine or 5-FU) chemotherapy from 2010 to 2014 was performed. Univariate and multivariate predictors of resection and survival were determined. A total of 92 patients (new chemotherapy = 61, old chemotherapy = 31) were analyzed, of which 19 (21%) underwent eventual resection (median overall survival [OS] = 32 vs. 14.3 months for unresected patients, P = 0.0002). For the overall cohort, resection (hazard ratio [HR] 0.261, P = 0.014), radiation therapy (HR 0.458, P = 0.004), number of lines of chemotherapy (HR 0.486, P = 0.012), and new chemotherapy (HR 0.593 vs. old regimens, P = 0.065) were independent predictors of OS on multivariate analyses (MVA). On MVA, predictors of eventual resection were head and neck tumors (OR 0.307, P = 0.033) or SMA involvement (OR 0.285, P = 0.023). In nonresected patients (73), MVA showed treatment with new chemotherapy (HR 0.452, P = 0.006), radiation (HR 0.459, P = 0.006), and number of lines of CT (HR 0.705, P = 0.013) to be predictors of survival. In LAPC, use of FOLFIRNOX and/or gemcitabine/nab-paclitaxel is associated with improved survival compared with older chemotherapy regimens, regardless of eventual resection. Tumor location and relationship to certain vasculature are important determinants of resection in this cohort.

A phase ii study of gemcitabine and capecitabine in patients with advanced renal cell cancer: Southwest Oncology Group Study S0312.

PubMed

Van Veldhuizen, Peter J; Hussey, Michael; Lara, Primo N; Mack, Philip C; Gandour-Edwards, Regina; Clark, Joseph I; Lange, Marianne K; Crawford, David E

2009-10-01

Gemcitabine plus capecitabine has moderate efficacy in patients with advanced renal cell cancer (RCC) but has considerable toxicity. We evaluated the efficacy and toxicity of a modified dose-schedule of this doublet in patients with metastatic RCC. Chemotherapy-naive patients were treated with gemcitabine at 900 mg/m2 on days 1, 8, and 15 and with capecitabine at 625 mg/m2 twice daily on days 1 through 21, and every 28 days thereafter. The primary end point was response rate (RR). No further evaluation of this regimen would be pursued if the RR was ≤ 5%. In an exploratory analysis, we also evaluated potential markers of prognosis and treatment response, including thymidylate synthase, PTEN, pAKT, pmTOR, XRCC1, and ERCC1. Of 43 patients, 1 was ineligible and 2 were not analyzable. There was 1 complete response and 3 partial responses, for an overall RR of 10% (95% CI = 3, 24). Nineteen patients (48%) had stable disease. The 6-month freedom-from-treatment-failure and overall survival rates were 20% (95% CI = 8, 32) and 75% (95% CI = 62, 88), respectively. Median survival time was 23 months (95% CI = 10, 37). One patient each experienced grade 4 neutropenia, fatigue, thrombocytopenia, and hemolysis with renal failure. The most common grade 3 toxicities were neutropenia (12 patients), fatigue (5), and leucopenia (4). Patients with a best response of stable disease or better were more likely to have decreased expression of PTEN and increased expression of pmTOR. Gemcitabine plus capecitabine at this reduced dose-schedule benefits a small percentage of patients with RCC with an acceptable toxicity profile.

A phase II trial of Cremorphor EL-free paclitaxel (Genexol-PM) and gemcitabine in patients with advanced non-small cell lung cancer.

PubMed

Ahn, Hee Kyung; Jung, Minkyu; Sym, Sun Jin; Shin, Dong Bok; Kang, Shin Myung; Kyung, Sun Young; Park, Jeong-Woong; Jeong, Sung Hwan; Cho, Eun Kyung

2014-08-01

Genexol-PM is a Cremorphor EL (CrEL)-free polymeric micelle formulation of paclitaxel that allows higher-dose administration with less hypersensitivity. This study was designed to evaluate the efficacy and safety of Genexol-PM and gemcitabine combination in advanced non-small cell lung cancer patients as a first-line treatment. This is a prospective, single-arm, single-center phase II study. Patients with advanced NSCLC received Genexol-PM at 230 mg/m(2) on day 1 and gemcitabine 1,000 mg/m(2) on day 1 and day 8 of a 3-week cycle. Six cycles of chemotherapy were planned unless there was disease progression. The primary endpoint was overall response rate. Forty-three patients received the study drugs with a median of 4 cycles per patient (range 1-6). The overall response rate was 46.5%. The median progression-free survival was 4.0 months (95% CI 2.0-6.0 months), and median overall survival was 14.8 months (95% CI 9.1-20.5 months). The most common toxicities were anemia (n = 29, 67%), asthenia (n = 17, 40%), myalgia (n = 16, 37%), peripheral neuropathy (n = 15, 35 %), and diarrhea (n = 12, 30%). The most common grade 3/4 adverse events were neutropenia (n = 7, 16%) and pneumonia (n = 5, 12%). Two patients died of pneumonia and dyspnea. CrEL-free paclitaxel in combination with gemcitabine demonstrated favorable antitumor activity with little emetogenicities in non-small cell lung cancer patients. However, frequent grade 3/4 toxicities were observed, and safety should be evaluated thoroughly in future studies.

Gemcitabine or gemcitabine plus oxaliplatin in the first-line treatment of patients with advanced transitional cell carcinoma of the urothelium unfit for cisplatin-based chemotherapy: a randomized phase 2 study of the French Genitourinary Tumor Group (GETUG V01).

PubMed

Culine, Stéphane; Fléchon, Aude; Guillot, Aline; Le Moulec, Sylvestre; Pouessel, Damien; Rolland, Frédéric; Ravaud, Alain; Houédé, Nadine; Mignot, Laurent; Joly, Florence; Oudard, Stéphane; Gourgou, Sophie

2011-12-01

The optimal chemotherapy for patients with advanced transitional cell carcinoma of the urothelium who are not eligible for cisplatin remains to be defined. To assess the activity of gemcitabine alone (GEM) or in combination with oxaliplatin (GEMOX) in a randomized phase 2 trial. The primary end point was the objective response rate according to Response Evaluation Criteria in Solid Tumors criteria. The sample size was based on a two-stage Fleming design with p0=35% and p1=55%. At the end of the first stage designed to register 20 patients on each treatment arm, the observation of seven or more objective responses would have led to the inclusion of 30 more patients in each arm. From July 2004 to March 2009, 44 patients in 10 centers were randomly assigned into the GEM or the GEMOX arm, 22 on each treatment arm. The median age was 76 yr. Seven patients were included for a performance status (PS) of 2 only. The remaining 37 patients had an impaired renal function, 11 of whom also had a PS of 2. The median creatinine clearance was 45 ml/min (range: 30-80 ml/min). The trial was closed after the first part because the GEMOX arm did not reach the targeted objective response rate to proceed further. Oxaliplatin does not add any significant activity (in terms of response rates) compared with gemcitabine alone in patients with advanced transitional cell carcinoma of the urothelium who are ineligible for cisplatin. Copyright © 2011 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Bitter melon juice exerts its efficacy against pancreatic cancer via targeting both bulk and cancer stem cells.

PubMed

Dhar, Deepanshi; Deep, Gagan; Kumar, Sushil; Wempe, Michael F; Raina, Komal; Agarwal, Chapla; Agarwal, Rajesh

2018-05-04

Pancreatic cancer (PanC) is one of the deadliest malignancies worldwide and frontline treatment with gemcitabine becomes eventually ineffective due to increasing PanC resistance, suggesting additional approaches are needed to manage PanC. Recently, we have shown the efficacy of bitter melon juice (BMJ) against PanC cells, including those resistant to gemcitabine. Since cancer stem cells (CSCs) are actively involved in PanC initiation, progression, relapse and drug-resistance, here we assessed BMJ ability in targeting pancreatic cancer-associated cancer stem cells (PanC-CSCs). We found BMJ efficacy against CD44 + /CD24 + /EpCAM high enriched PanC-CSCs in spheroid assays; BMJ also increased the sensitivity of gemcitabine-resistant PanC-CSCs. Exogenous addition of BMJ to PanC-CSC generated spheroids (not pre-exposed to BMJ) also significantly reduced spheroid number and size. Mechanistically, BMJ effects were associated with a decrease in the expression of genes and proteins involved in PanC-CSC renewal and proliferation. Specifically, immunofluorescence staining showed that BMJ decreases protein expression/nuclear localization of CSC-associated transcription factors SOX2, OCT4 and NANOG, and CSC marker CD44. Immunohistochemical analysis of MiaPaCa2 xenografts from BMJ treated animals also showed a significant decrease in the levels of CSC-associated transcription factors. Together, these results show BMJ potential in targeting PanC-CSC pool and associated regulatory pathways, suggesting the need for further investigation of its efficacy against PanC growth and progression including gemcitabine-resistant PanC. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

A phase I study evaluating the role of the anti-epidermal growth factor receptor (EGFR) antibody cetuximab as a radiosensitizer with chemoradiation for locally advanced pancreatic cancer

PubMed Central

Arnoletti, J. P.; Frolov, A.; Eloubeidi, M.; Keene, K.; Posey, J.; Wood, T.; Greeno, Edward; Jhala, N.; Varadarajulu, S.; Russo, S.; Christein, J.; Oster, R.; Buchsbaum, D. J.; Vickers, S. M.

2012-01-01

Purpose (1) To determine the safety of the epidermal growth factor receptor (EGFR) antibody cetuximab with concurrent gemcitabine and abdominal radiation in the treatment of patients with locally advanced adenocarcinoma of the pancreas. (2) To evaluate the feasibility of pancreatic cancer cell epithelial–mesenchymal transition (EMT) molecular profiling as a potential predictor of response to anti-EGFR treatment. Methods Patients with non-metastatic, locally advanced pancreatic cancer were treated in this dose escalation study with gemcitabine (0–300 mg/m2/week) given concurrently with cetuximab (400 mg/m2 loading dose, 250 mg/m2 weekly maintenance dose) and abdominal irradiation (50.4 Gy). Expression of E-cadherin and vimentin was assessed by immunohistochemistry in diagnostic endoscopic ultrasound fine-needle aspiration (EUS-FNA) specimens. Results Sixteen patients were enrolled in 4 treatment cohorts with escalating doses of gemcitabine. Incidence of grade 1–2 adverse events was 96%, and incidence of 3–4 adverse events was 9%. There were no treatment-related mortalities. Two patients who exhibited favorable treatment response underwent surgical exploration and were intraoperatively confirmed to have unresectable tumors. Median overall survival was 10.5 months. Pancreatic cancer cell expression of E-cadherin and vimentin was successfully determined in EUS-FNA specimens from 4 patients. Conclusions Cetuximab can be safely administered with abdominal radiation and concurrent gemcitabine (up to 300 mg/m2/week) in patients with locally advanced adenocarcinoma of the pancreas. This combined therapy modality exhibited limited activity. Diagnostic EUS-FNA specimens could be analyzed for molecular markers of EMT in a minority of patients with pancreatic cancer. PMID:20589377

Phase I Study of Conformal Radiotherapy and Concurrent Full-Dose Gemcitabine With Erlotinib for Unresected Pancreatic Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robertson, John M., E-mail: jrobertson@beaumont.edu; Margolis, Jeffrey; Jury, Robert P.

2012-02-01

Purpose: To determine the recommended dose of radiotherapy when combined with full-dose gemcitabine and erlotinib for unresected pancreas cancer. Methods and Materials: Patients with unresected pancreatic cancer (Zubrod performance status 0-2) were eligible for the present study. Gemcitabine was given weekly for 7 weeks (1,000 mg/m{sup 2}) with erlotinib daily for 8 weeks (100 mg). A final toxicity assessment was performed in Week 9. Radiotherapy (starting at 30 Gy in 2-Gy fractions, 5 d/wk) was given to the gross tumor plus a 1-cm margin starting with the first dose of gemcitabine. A standard 3 plus 3 dose escalation (an additionalmore » 4 Gy within 2 days for each dose level) was used, except for the starting dose level, which was scheduled to contain 6 patients. In general, Grade 3 or greater gastrointestinal toxicity was considered a dose-limiting toxicity, except for Grade 3 anorexia or Grade 3 fatigue alone. Results: A total of 20 patients were treated (10 men and 10 women). Nausea, vomiting, and infection were significantly associated with the radiation dose (p = .01, p = .03, and p = .03, respectively). Of the 20 patients, 5 did not complete treatment and were not evaluable for dose-escalation purposes (3 who developed progressive disease during treatment and 2 who electively discontinued it). Dose-limiting toxicity occurred in none of 6 patients at 30 Gy, 2 of 6 at 34 Gy, and 1 of 3 patients at 38 Gy. Conclusion: The results of the present study have indicated that the recommended Phase II dose is 30 Gy in 15 fractions.« less

Cisplatin plus gemcitabine for treatment of breast cancer patients with brain metastases; a preferential option for triple negative patients?

PubMed

Erten, Cigdem; Demir, Lutfiye; Somali, Isil; Alacacioglu, Ahmet; Kucukzeybek, Yuksel; Akyol, Murat; Can, Alper; Dirican, Ahmet; Bayoglu, Vedat; Tarhan, Mustafa Oktay

2013-01-01

To assess the efficacy and tolerability of Cisplatin plus Gemcitabine combination in patients with brain metastases (BM) from breast cancer (BC). Eighteen BC patients with BM who were treated with Cisplatin plus Gemcitabine regimen between 2003-2011 were evaluated. A median of 6 cycles of this regimen were received, in fifteen patients (83.3%) as first-line chemotherapy, in 2 as second- line and in 1 as third-line after diagnosis of BM. Dose reduction was performed in 11 (61.1%) patients; major reasons were neutropenia and leukopenia. Grade III neutropenia and Grade II trombocytopenia rates were 33.3% and 16.7% respectively. Overall response rate (ORR; complete+partial response rate) was 33.4% (n=6) for the entire study population; triple negative patients achieved an 66.6% ORR while hormone receptor (HR) positive patients had 25% and HER2 positive patients 12.5%. Median progression-free survival was 5.6 months (2.4-8.8 months, 95%CI) and longer in patients with triple negative breast cancer (TNBC) (median 7.4 months, 95%CI, 2.4-12.3 months) than the patients with other subtypes (median 5 months for HER2 positive and 3.6 months for HR positive patients). Median PFS of the patients with TNBC who received this regimen as first-line was 9.2 months (5.2-13.2 months, 95%CI). Cisplatin plus Gemcitabine may be a treatment option for patients with BM from breast cancer. Longer PFS and higher response rates are results that support the usage of this regimen especially for the triple negative subtype. However, further prospective and randomized trials are clearly required to provide more exact information.

A Cost-Effectiveness Analysis of Gemcitabine plus Cisplatin Versus Gemcitabine Alone for Treatment of Advanced Biliary Tract Cancer in Japan.

PubMed

Tsukiyama, Ikuto; Ejiri, Masayuki; Yamamoto, Yoshihiro; Nakao, Haruhisa; Yoneda, Masashi; Matsuura, Katsuhiko; Arakawa, Ichiro; Saito, Hiroko; Inoue, Tadao

2017-12-01

This study assessed the cost-effectiveness of combination treatment with gemcitabine and cisplatin compared to treatment with gemcitabine alone for advanced biliary tract cancer (BTC) in Japan. A monthly transmitted Markov model of three states was constructed based on the Japan BT-22 trial. Transition probabilities among the health states were derived from a trial conducted in Japan and converted to appropriate parameters for our model. The associated cost components, obtained from a receipt-based survey undertaken at the Aichi Medical University Hospital, were those related to inpatient care, outpatient care, and treatment for BTC. Costs for palliative care and treatment of adverse events were obtained from the National Health Insurance price list. We estimated cost-effectiveness per quality-adjusted life year (QALY) at a time horizon of 36 months. An annual discount of 3 % for both cost and outcome was considered. The base case outcomes indicated that combination therapy was less cost-effective than monotherapy when the incremental cost-effectiveness ratio (ICER) was approximately 14 million yen per QALY gained. The deterministic sensitivity analysis of the ICER revealed that the ICER of the base case was robust. A probabilistic analysis conducted with 10,000-time Monte Carlo simulations demonstrated efficacy at the willingness to pay threshold of 6 million yen per QALY gained for approximately 33 % of the population. In Japan, combination therapy is less cost-effective than monotherapy for treating advanced BTC, regardless of the statistical significance of the two therapies. Useful information on the cost-effectiveness of chemotherapy is much needed for the treatment of advanced BTC in Japan.

Aspirin counteracts cancer stem cell features, desmoplasia and gemcitabine resistance in pancreatic cancer

PubMed Central

Zhang, Yiyao; Liu, Li; Fan, Pei; Bauer, Nathalie; Gladkich, Jury; Ryschich, Eduard; Bazhin, Alexandr V.; Giese, Nathalia A.; Strobel, Oliver; Hackert, Thilo; Hinz, Ulf; Gross, Wolfgang; Fortunato, Franco; Herr, Ingrid

2015-01-01

Pancreatic ductal adenocarcinoma (PDA) is characterized by an extremely poor prognosis. An inflammatory microenvironment triggers the pronounced desmoplasia, the selection of cancer stem-like cells (CSCs) and therapy resistance. The anti-inflammatory drug aspirin is suggested to lower the risk for PDA and to improve the treatment, although available results are conflicting and the effect of aspirin to CSC characteristics and desmoplasia in PDA has not yet been investigated. We characterized the influence of aspirin on CSC features, stromal reactions and gemcitabine resistance. Four established and 3 primary PDA cell lines, non-malignant cells, 3 patient tumor-derived CSC-enriched spheroidal cultures and tissues from patients who did or did not receive aspirin before surgery were analyzed using MTT assays, flow cytometry, colony and spheroid formation assays, Western blot analysis, antibody protein arrays, electrophoretic mobility shift assays (EMSAs), immunohistochemistry and in vivo xenotransplantation. Aspirin significantly induced apoptosis and reduced the viability, self-renewal potential, and expression of proteins involved in inflammation and stem cell signaling. Aspirin also reduced the growth and invasion of tumors in vivo, and it significantly prolonged the survival of mice with orthotopic pancreatic xenografts in combination with gemcitabine. This was associated with a decreased expression of markers for progression, inflammation and desmoplasia. These findings were confirmed in tissue samples obtained from patients who had or had not taken aspirin before surgery. Importantly, aspirin sensitized cells that were resistant to gemcitabine and thereby enhanced the therapeutic efficacy. Aspirin showed no obvious toxic effects on normal cells, chick embryos or mice. These results highlight aspirin as an effective, inexpensive and well-tolerated co-treatment to target inflammation, desmoplasia and CSC features PDA. PMID:25846752

Gemcitabine and cisplatin in a concomitant alternating chemoradiotherapy program for locally advanced head-and-neck cancer: A pharmacology-guided schedule

DOE Office of Scientific and Technical Information (OSTI.GOV)

Numico, Gianmauro; Russi, Elvio G.; Vitiello, Raffele

Purpose: Administration of gemcitabine together with cisplatin at cytotoxic doses in a chemoradiotherapy regimen is hampered by a high degree of local toxicity. Using the pharmacologic properties of the drug we designed a modified schedule aimed at reducing toxicity while preserving activity. Methods and Materials: Patients with squamous cell carcinomas of the oral cavity, pharynx and larynx, bulky T4, and/or N2 to N3 were eligible. Gemcitabine was administered at a dose of 800 mg/m{sup 2} on Days 1 and 12 and cisplatin at a dose of 20 mg/m{sup 2} on Days 2 to 5, every 21 days for 3 courses.more » Radiotherapy, delivered with standard fractionation, was given on Days 8 to 12 and 15 to 19 and was repeated 3 times up to a total dose of {>=}60 Gy. Results: A total of 28 patients were selected. Grade 3 to 4 stomatitis was recorded in 25 patients (89%). Thirteen patients (46%) experienced Grade 3 to 4 neutropenia. Febrile neutropenia occurred in 8 patients (29%) and in 2 was complicated by infection and death. The overall complete response rate was 79%. At a median follow up of 71 months, 11 patients had a locoregional relapse (3-year locoregional control, 64%); 6 patients had distant metastases, among whom only 2 were without locoregional recurrence. The 3-year progression-free survival is 39% and 3-year overall survival has been 43%. Conclusion: The schedule modification did not attenuate local toxicity. Moreover, infections and especially pneumonia, were a major problem. The high activity of gemcitabine when combined with radiotherapy would most likely be better exploited in the context of modified radiation schemes.« less

Phase II Trial of Full-Dose Gemcitabine and Bevacizumab in Combination With Attenuated Three-Dimensional Conformal Radiotherapy in Patients With Localized Pancreatic Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Small, William, E-mail: wsmall@nmff.or; Mulcahy, Mary F.; Rademaker, Alfred

Purpose: To evaluate response rate, survival, and toxicity in patients with nonmetastatic pancreatic cancer treated with gemcitabine, bevacizumab, and radiotherapy. Methods and Materials: Patients received three cycles of therapy over 10 weeks. In total, treatment consisted of intravenous (IV) gemcitabine, 1,000 mg/m{sup 2}, every 1 to 2 weeks (7 doses), IV bevacizumab, 10 mg/kg every 2 weeks (5 doses), and 36 Gy of radiotherapy (2.4-Gy fractions during cycle two). Response was assessed by cross-sectional imaging and carbohydrate antigen 19-9 (CA 19-9) levels. Patients with resectable tumors underwent surgery 6 to 8 weeks after the last dose of bevacizumab. Maintenance gemcitabinemore » and bevacizumab doses were delivered to patients who had unresected tumors and no progression. Results: Twenty-eight of the 32 enrolled patients completed all three cycles. The median follow-up was 11.07 months. Most grade 3 or 4 toxicities occurred in the initial treatment phase; the most frequent toxicities were leukopenia (21%), neutropenia (17%), and nausea (17%). At week 10, 1 patient (4%) had a complete response, 2 patients (7%) had partial responses, 21 patients (75%) had stable disease, and 4 patients (14%) had progressive disease. The median pretreatment and posttreatment CA 19-9 levels (25 patients) were 184.3 and 57.9 U/ml, respectively (p = 0.0006). One of 10 patients proceeding to surgery experienced a major complication. Two of 6 patients undergoing resection had complete pathologic responses. The median progression-free and overall survival durations were 9.9 months and 11.8 months, respectively. Conclusions: The combination of full-dose gemcitabine, bevacizumab, and radiotherapy was active and was not associated with a high rate of major surgical complications.« less

Bio-Fluid Dynamics in a Centimeter-Scale Diagnostics Incubator with Integrated Perfusion

NASA Astrophysics Data System (ADS)

Vukasinovic, J.; Cullen, D. K.; Glezer, A.; Laplaca, M. C.

2006-11-01

Growing demands for long-term incubation of biologically faithful, three-dimensional neuronal and other cultures during extended physiological studies require efficient perfusion platforms with functional vasculatures that mimic the in vivo condition in a thermally regulated environment. While thermostatically controlled incubation baths with capillary action perfusion are available, their use is confined to specific experimental conditions. The interstitial nutrient and gas delivery remains diffusion limited over the long term and cultures decay metabolically. To overcome these problems, we describe simple fabrication and experimental characterization of a compact, diagnostics incubator that allows in situ monitoring of culture activity with a superior control of critical biological functions using convectively enhanced heat and mass transport. To overcome intercellular diffusion barriers culture is exposed to a direct flow of media issuing from an array of micro-nozzles that are directed normal to the substrate upholding the culture, and further improved by 3-D convection induced by jet interactions and biased, peripheral perfusate extraction through an array of microchannels as demonstrated by microPIV measurements.

Bridging the divide

PubMed Central

McLean, Peter F; Cooley, Lynn

2014-01-01

Ring canals are made from arrested cleavage furrows, and provide direct cytoplasmic connections among sibling cells. They are well documented for their participation in Drosophila oogenesis, but little is known about their role in several somatic tissues in which they are also found. Using a variety of genetic tools in live and fixed tissue, we recently demonstrated that rapid intercellular exchange occurs through somatic ring canals by diffusion, and presented evidence that ring canals permit equilibration of protein among transcriptionally mosaic cells. We also used a novel combination of markers to evaluate the extent of protein movement within and across mitotic clones in follicle cells and imaginal discs, providing evidence of robust movement of GFP between the 2 sides of mitotic clones and frequently into non-recombined cells. These data suggest that, depending on the experimental setup and proteins of interest, inter-clonal diffusion of protein may alter the interpretation of clonal data in follicle cells. Here, we discuss these results and provide additional insight into the impact of ring canals in Drosophila somatic tissues. PMID:24406334

A portion of plant airborne communication is endorsed by uptake and metabolism of volatile organic compounds.

PubMed

Matsui, Kenji

2016-08-01

Plants have the ability to sense volatile organic compounds (VOCs) so as to efficiently adapt to their environment. The mechanisms underlying such plant 'olfactory' systems are largely unknown. Here I would like to propose that the metabolism of VOCs in plant tissues is one of the mechanisms by which plants sense VOCs. During the gas-exchange that is essential for photosynthesis, VOCs in the atmosphere are taken into the intercellular spaces of leaves. Each VOC is partitioned between the gas phase (intercellular space) and liquid phase (cell wall) at a certain ratio determined by Henry's law. The VOCs in the cell wall diffuse through the plasma membrane to the cytosol depending on their oil/water partition coefficients. Plants detoxify some VOCs, especially those that are oxidized, through glycosylation, glutathionylation, and reduction. These metabolic processes lower the concentration of VOCs in the cytosol, which facilitates further cytosolic uptake. As a result, vigorous metabolism of VOCs in the cytosol can lead to a substantial accumulation of VOC metabolites and the depletion of glutathione or NADPH. One such metabolite (a VOC glycoside) is known to mount a direct defense against herbivores, whilst deprivation of glutathione and NADPH can fortify plants with responses similar to the oxidative stress response. Copyright © 2016 Elsevier Ltd. All rights reserved.

Intercellular and intracellular signalling systems that globally control the expression of virulence genes in plant pathogenic bacteria.

PubMed

Ham, Jong Hyun

2013-04-01

Plant pathogenic bacteria utilize complex signalling systems to control the expression of virulence genes at the cellular level and within populations. Quorum sensing (QS), an important intercellular communication mechanism, is mediated by different types of small molecules, including N-acyl homoserine lactones (AHLs), fatty acids and small proteins. AHL-mediated signalling systems dependent on the LuxI and LuxR family proteins play critical roles in the virulence of a wide range of Gram-negative plant pathogenic bacteria belonging to the Alphaproteobacteria, Betaproteobacteria and Gammaproteobacteria. Xanthomonas spp. and Xylella fastidiosa, members of the Gammaproteobacteria, however, possess QS systems that are mediated by fatty acid-type diffusible signal factors (DSFs). Recent studies have demonstrated that Ax21, a 194-amino-acid protein in Xanthomonas oryzae pv. oryzae, plays dual functions in activating a rice innate immune pathway through binding to the rice XA21 pattern recognition receptor and in regulating bacterial virulence and biofilm formation as a QS signal molecule. In xanthomonads, DSF-mediated QS systems are connected with the signalling pathways mediated by cyclic diguanosine monophosphate (c-di-GMP), which functions as a second messenger for the control of virulence gene expression in these bacterial pathogens. © 2012 BSPP AND BLACKWELL PUBLISHING LTD.

Variations in gap junctional intercellular communication and connexin expression in fibroblasts derived from keloid and hypertrophic scars.

PubMed

Lu, Feng; Gao, JianHua; Ogawa, Rei; Hyakusoku, Hiko

2007-03-01

Expression of connexins and other constituent proteins of gap junctions along with gap junctional intercellular communication are involved in cellular development and differentiation processes. In addition, an increasing number of hereditary skin disorders appear to be linked to connexins. Therefore, in this report, the authors studied in vitro gap junctional intercellular communication function and connexin expression in fibroblasts derived from keloid and hypertrophic scar patients. Fibroblasts harvested from each of six keloid and hypertrophic scar patients were used for this study. Gap junctional intercellular communication function was investigated using the gap fluorescence recovery after photobleaching method, and expression of connexin proteins was studied using quantitative confocal microscopic analyses. Compared with normal skin, a decreased level of gap junctional intercellular communication was seen in fibroblasts derived from hypertrophic scar tissue, whereas an extremely low gap junctional intercellular communication level was detected in fibroblasts derived from keloid tissue. We also detected little connexin 43 (Cx43) protein localized in fibroblasts derived from keloids. Moreover, Cx43 protein levels were much lower in fibroblasts derived from hypertrophic scars than in those derived from normal skin. The authors' data suggest that the loss of gap junctional intercellular communication and connexin expression may affect intercellular recognition and thus break the proliferation and apoptosis balance in fibroblasts derived from keloid and hypertrophic scar tissue.

Zein Microneedles for Localized Delivery of Chemotherapeutic Agents to Treat Breast Cancer: Drug Loading, Release Behavior, and Skin Permeation Studies.

PubMed

Bhatnagar, Shubhmita; Kumari, Pooja; Pattarabhiran, Srijanaki Paravastu; Venuganti, Venkata Vamsi Krishna

2018-05-01

Localized delivery of chemotherapeutic agents to treat breast cancer could limit their adverse drug reactions. The aim of this study was to investigate the influence of physico-chemical properties of chemotherapeutic agents in their loading, release behavior, and skin permeation using microneedles. Zein microneedles were fabricated using the micromolding technique containing 36 microneedles in a 1-cm 2 area. These microneedles were loaded with two anti-breast cancer drugs, tamoxifen and gemcitabine, having different water solubilities. Entrapment or surface coating of chemotherapeutic agents in zein microneedles was optimized to achieve greater loading efficiency. The greatest loading achieved was 607 ± 21 and 1459 ± 74 μg for tamoxifen and gemcitabine using the entrapment approach, respectively. Skin permeation studies in excised porcine skin showed that the coating on microneedles approach results in greater skin deposition for tamoxifen; while the poke-and-patch approach would provide greater skin permeation for gemcitabine. Taken together, it can be concluded that different loading strategies and skin penetration approaches have to be studied for delivery of small molecules using polymeric microneedles.

The preclinical evaluation of TIC10/ONC201 as an anti-pancreatic cancer agent.

PubMed

Zhang, Qiangbo; Wang, Hong; Ran, Lin; Zhang, Zongli; Jiang, Runde

2016-08-05

Here we evaluated the potential anti-pancreatic cancer activity by TIC10/ONC201, a first-in-class small-molecule inducer of tumor necrosis (TNF)-related apoptosis-inducing ligand (TRAIL). The in vitro results showed that TIC10 induced potent cytotoxic and cytostatic activities in several human pancreatic cancer cell lines (Panc-1, Mia-PaCa2, AsPC-1 or L3.6). TIC10 activated both extrinsic (TRAIL-caspase-8-dependent) and endogenous/mitochondrial (caspase-9-dependent) apoptosis pathways in the pancreatic cancer cells. Molecularly, we showed that TIC10 inhibited Akt-Erk activation, yet induced TRAIL expression in pancreatic cancer cells. Significantly, TIC10, at a relatively low concentration, sensitized gemcitabine-induced growth inhibition and apoptosis against pancreatic cancer cells. Further, TIC10 and gemcitabine synergistically inhibited Panc-1 xenograft growth in SCID mice. The combination treatment also significantly improved mice survival. In addition, Akt-Erk in-activation and TRAIL/cleaved-caspase-8 induction were observed in TIC10-treated Panc-1 xenografts. Together, the preclinical results of the study demonstrate the potent anti-pancreatic cancer activity by TIC10, or with gemcitabine. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of a Non Thermal Plasma Treatment Alone or in Combination with Gemcitabine in a MIA PaCa2-luc Orthotopic Pancreatic Carcinoma Model

PubMed Central

Brullé, Laura; Vandamme, Marc; Riès, Delphine; Martel, Eric; Robert, Eric; Lerondel, Stéphanie; Trichet, Valérie; Richard, Serge; Pouvesle, Jean-Michel; Le Pape, Alain

2012-01-01

Pancreatic tumors are the gastrointestinal cancer with the worst prognosis in humans and with a survival rate of 5% at 5 years. Nowadays, no chemotherapy has demonstrated efficacy in terms of survival for this cancer. Previous study focused on the development of a new therapy by non thermal plasma showed significant effects on tumor growth for colorectal carcinoma and glioblastoma. To allow targeted treatment, a fibered plasma (Plasma Gun) was developed and its evaluation was performed on an orthotopic mouse model of human pancreatic carcinoma using a MIA PaCa2-luc bioluminescent cell line. The aim of this study was to characterize this pancreatic carcinoma model and to determine the effects of Plasma Gun alone or in combination with gemcitabine. During a 36 days period, quantitative BLI could be used to follow the tumor progression and we demonstrated that plasma gun induced an inhibition of MIA PaCa2-luc cells proliferation in vitro and in vivo and that this effect could be improved by association with gemcitabine possibly thanks to its radiosensitizing properties. PMID:23300736

Management strategies in pancreatic cancer.

PubMed

Campen, Christopher J; Dragovich, Tomislav; Baker, Amanda F

2011-04-01

Current first-line and adjuvant chemotherapeutic strategies for management of patients with pancreatic cancer are reviewed. Pancreatic adenocarcinoma is the 10th most prevalent cancer and the fourth most common cause of cancer deaths in the United States. More than 80% of patients with pancreatic cancer are diagnosed with locally advanced or metastatic disease and are not candidates for surgery; these patients often require multimodal treatment. The most widely used chemotherapy for such patients, as well as patients requiring adjuvant therapy after surgery, is gemcitabine or gemcitabine-based chemotherapy. All current chemotherapies for pancreatic cancer are associated with dose-limiting hematologic toxicity and other adverse effects that require ongoing monitoring and dosage adjustment to balance the benefits and risks of treatment. Pharmacists can play an important role in monitoring and providing drug information and guidance to patients and oncologists. Current investigational strategies include efforts to improve chemotherapy response rates and outcomes through modulation of cell signaling pathways and use of nanotechnology to improve drug delivery. Current management of pancreatic cancer is multifaceted, involving anticancer therapy, supportive care, and toxicity management. Standard systemic therapy with gemcitabine as a single agent or in combination with other cytotoxic agents provides modest benefits in terms of response and symptom control.

Randomized phase II--study evaluating EGFR targeting therapy with cetuximab in combination with radiotherapy and chemotherapy for patients with locally advanced pancreatic cancer--PARC: study protocol [ISRCTN56652283].

PubMed

Krempien, R; Muenter, M W; Huber, P E; Nill, S; Friess, H; Timke, C; Didinger, B; Buechler, P; Heeger, S; Herfarth, K K; Abdollahi, A; Buchler, M W; Debus, J

2005-10-11

Pancreatic cancer is the fourth commonest cause of death from cancer in men and women. Advantages in surgical techniques, radiation therapy techniques, chemotherapeutic regimes, and different combined-modality approaches have yielded only a modest impact on the prognosis of patients with pancreatic cancer. Thus there is clearly a need for additional strategies. One approach involves using the identification of a number of molecular targets that may be responsible for the resistance of cancer cells to radiation or to other cytotoxic agents. As such, these molecular determinants may serve as targets for augmentation of the radiotherapy or chemotherapy response. Of these, the epidermal growth factor receptor (EGFR) has been a molecular target of considerable interest and investigation, and there has been a tremendous surge of interest in pursuing targeted therapy of cancers via inhibition of the EGFR. The PARC study is designed as an open, controlled, prospective, randomized phase II trial. Patients in study arm A will be treated with chemoradiation using intensity modulated radiation therapy (IMRT) combined with gemcitabine and simultaneous cetuximab infusions. After chemoradiation the patients receive gemcitabine infusions weekly over 4 weeks. Patients in study arm B will be treated with chemoradiation using intensity modulated radiation therapy (IMRT) combined with gemcitabine and simultaneous cetuximab infusions. After chemoradiation the patients receive gemcitabine weekly over 4 weeks and cetuximab infusions over 12 weeks. A total of 66 patients with locally advanced adenocarcinoma of the pancreas will be enrolled. An interim analysis for patient safety reasons will be done one year after start of recruitment. Evaluation of the primary endpoint will be performed two years after the last patient's enrollment. The primary objective of this study is to evaluate the feasibility and the toxicity profile of trimodal therapy in pancreatic adenocarcinoma with chemoradiation therapy with gemcitabine and intensity modulated radiation therapy (IMRT) and EGFR-targeted therapy using cetuximab and to compare between two different methods of cetuximab treatment schedules (concomitant versus concomitant and sequential cetuximab treatment). Secondary objectives are to determine the role and the mechanism of cetuximab in patient's chemoradiation regimen, the response rate, the potential of this combined modality treatment to concert locally advanced lesions to potentially resectable lesions, the time to progression interval and the quality of life.

Theranostic reduction-sensitive gemcitabine prodrug micelles for near-infrared imaging and pancreatic cancer therapy

NASA Astrophysics Data System (ADS)

Han, Haijie; Wang, Haibo; Chen, Yangjun; Li, Zuhong; Wang, Yin; Jin, Qiao; Ji, Jian

2015-12-01

A biodegradable and reduction-cleavable gemcitabine (GEM) polymeric prodrug with in vivo near-infrared (NIR) imaging ability was reported. This theranostic GEM prodrug PEG-b-[PLA-co-PMAC-graft-(IR820-co-GEM)] was synthesized by ring-opening polymerization and ``click'' reaction. The as-prepared reduction-sensitive prodrug could self-assemble into prodrug micelles in aqueous solution confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). In vitro drug release studies showed that these prodrug micelles were able to release GEM in an intracellular-mimicking reductive environment. These prodrug micelles could be effectively internalized by BxPC-3 pancreatic cancer cells, which were observed by confocal laser scanning microscopy (CLSM). Meanwhile, a methyl thiazolyl tetrazolium (MTT) assay demonstrated that this prodrug exhibited high cytotoxicity against BxPC-3 cells. The in vivo whole-animal near-infrared (NIR) imaging results showed that these prodrug micelles could be effectively accumulated in tumor tissue and had a longer blood circulation time than IR820-COOH. The endogenous reduction-sensitive gemcitabine prodrug micelles with the in vivo NIR imaging ability might have great potential in image-guided pancreatic cancer therapy.A biodegradable and reduction-cleavable gemcitabine (GEM) polymeric prodrug with in vivo near-infrared (NIR) imaging ability was reported. This theranostic GEM prodrug PEG-b-[PLA-co-PMAC-graft-(IR820-co-GEM)] was synthesized by ring-opening polymerization and ``click'' reaction. The as-prepared reduction-sensitive prodrug could self-assemble into prodrug micelles in aqueous solution confirmed by dynamic light scattering (DLS) and transmission electron microscopy (TEM). In vitro drug release studies showed that these prodrug micelles were able to release GEM in an intracellular-mimicking reductive environment. These prodrug micelles could be effectively internalized by BxPC-3 pancreatic cancer cells, which were observed by confocal laser scanning microscopy (CLSM). Meanwhile, a methyl thiazolyl tetrazolium (MTT) assay demonstrated that this prodrug exhibited high cytotoxicity against BxPC-3 cells. The in vivo whole-animal near-infrared (NIR) imaging results showed that these prodrug micelles could be effectively accumulated in tumor tissue and had a longer blood circulation time than IR820-COOH. The endogenous reduction-sensitive gemcitabine prodrug micelles with the in vivo NIR imaging ability might have great potential in image-guided pancreatic cancer therapy. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06734k

Gemcitabine-erlotinib versus gemcitabine-erlotinib-capecitabine in the first-line treatment of patients with metastatic pancreatic cancer: Efficacy and safety results of a phase IIb randomised study from the Spanish TTD Collaborative Group.

PubMed

Irigoyen, Antonio; Gallego, Javier; Guillén Ponce, Carmen; Vera, Ruth; Iranzo, Vega; Ales, Inmaculada; Arévalo, Sara; Pisa, Aleydis; Martín, Marta; Salud, Antonieta; Falcó, Esther; Sáenz, Alberto; Manzano Mozo, José Luis; Pulido, Gema; Martínez Galán, Joaquina; Pazo-Cid, Roberto; Rivera, Fernando; García García, Teresa; Serra, Olbia; Fernández Parra, Eva Ma; Hurtado, Alicia; Gómez Reina, Ma José; López Gomez, Luis Jesús; Martínez Ortega, Esther; Benavides, Manuel; Aranda, Enrique

2017-04-01

Gemcitabine and erlotinib have shown a survival benefit in the first-line setting in metastatic pancreatic cancer (mPC). The aim of this study was to assess whether combining capecitabine (C) with gemcitabine + erlotinib (GE) was safe and effective versus GE in patients with mPC. Previously untreated mPC patients were randomised to receive G (1000 mg/m 2 , days 1, 8, 15) + E (100 mg/day, days 1-28) + C (1660 mg/m 2 , days 1-21) or GE, q4 weeks, until progression or unacceptable toxicity. Primary end-point: progression-free survival (PFS); secondary end-points: overall survival (OS), response rate, relationship of rash with PFS/OS and safety. 120 patients were randomised, median age 63 years, ECOG status 0/1/2 33%/58%/8%; median follow-up 16.5 months. Median PFS in the gemcitabine-erlotinib-capecitabine (GEC) and GE arms was 4.3 and 3.8 months, respectively (hazard ratio [HR]: 0.88, 95% confidence interval [CI]: 0.58-1.31; p = 0.52). Median OS in the GEC and GE arms was 6.8 and 7.7 months, respectively (HR: 1.09, 95% CI: 0.72-1.63; p = 0.69). Grade 3/4 neutropenia (GEC 43% versus GE 15%; p = 0.0008) and mucositis (GEC 9% versus GE 0%; p = 0.03) were the only statistically significant differences in grade 3/4 adverse events. PFS and OS were significantly longer in patients with rash (grade ≥1) versus no rash (grade = 0): PFS 5.5 versus 2.0 months (HR = 0.39, 95% CI: 0.26-0.6; p < 0.0001) and OS: 9.5 versus 4.0 months (HR = 0.51, 95% CI: 0.33-0.77; p = 0.0014). PFS with GEC was not significantly different to that with GE in patients with mPC. Skin rash strongly predicted erlotinib efficacy. The study was registered with ClinicalTrials.gov: NCT01303029. Copyright © 2017 Elsevier Ltd. All rights reserved.

Localization of Protein Aggregation in Escherichia coli Is Governed by Diffusion and Nucleoid Macromolecular Crowding Effect

PubMed Central

Coquel, Anne-Sophie; Jacob, Jean-Pascal; Primet, Mael; Demarez, Alice; Dimiccoli, Mariella; Julou, Thomas; Moisan, Lionel

2013-01-01

Aggregates of misfolded proteins are a hallmark of many age-related diseases. Recently, they have been linked to aging of Escherichia coli (E. coli) where protein aggregates accumulate at the old pole region of the aging bacterium. Because of the potential of E. coli as a model organism, elucidating aging and protein aggregation in this bacterium may pave the way to significant advances in our global understanding of aging. A first obstacle along this path is to decipher the mechanisms by which protein aggregates are targeted to specific intercellular locations. Here, using an integrated approach based on individual-based modeling, time-lapse fluorescence microscopy and automated image analysis, we show that the movement of aging-related protein aggregates in E. coli is purely diffusive (Brownian). Using single-particle tracking of protein aggregates in live E. coli cells, we estimated the average size and diffusion constant of the aggregates. Our results provide evidence that the aggregates passively diffuse within the cell, with diffusion constants that depend on their size in agreement with the Stokes-Einstein law. However, the aggregate displacements along the cell long axis are confined to a region that roughly corresponds to the nucleoid-free space in the cell pole, thus confirming the importance of increased macromolecular crowding in the nucleoids. We thus used 3D individual-based modeling to show that these three ingredients (diffusion, aggregation and diffusion hindrance in the nucleoids) are sufficient and necessary to reproduce the available experimental data on aggregate localization in the cells. Taken together, our results strongly support the hypothesis that the localization of aging-related protein aggregates in the poles of E. coli results from the coupling of passive diffusion-aggregation with spatially non-homogeneous macromolecular crowding. They further support the importance of “soft” intracellular structuring (based on macromolecular crowding) in diffusion-based protein localization in E. coli. PMID:23633942

Gap Junction Regulation of Vascular Tone: Implications of Modulatory Intercellular Communication During Gestation

PubMed Central

Ampey, Bryan C.; Morschauser, Timothy J.; Lampe, Paul D.

2017-01-01

In the vasculature, gap junctions (GJ) play a multifaceted role by serving as direct conduits for cell–cell intercellular communication via the facilitated diffusion of signaling molecules. GJs are essential for the control of gene expression and coordinated vascular development in addition to vascular function. The coupling of endothelial cells to each other, as well as with vascular smooth muscle cells via GJs, plays a relevant role in the control of vasomotor tone, tissue perfusion and arterial blood pressure. The regulation of cell-signaling is paramount to cardiovascular adaptations of pregnancy. Pregnancy requires highly developed cell-to-cell coupling, which is affected partly through the formation of intercellular GJs by Cx43, a gap junction protein, within adjacent cell membranes to help facilitate the increase of uterine blood flow (UBF) in order to ensure adequate perfusion for nutrient and oxygen delivery to the placenta and thus the fetus. One mode of communication that plays a critical role in regulating Cx43 is the release of endothelial-derived vasodilators such as prostacyclin (PGI2) and nitric oxide (NO) and their respective signaling mechanisms involving second messengers (cAMP and cGMP, respectively) that are likely to be important in maintaining UBF. Therefore, the assertion we present in this review is that GJs play an integral if not a central role in maintaining UBF by controlling rises in vasodilators (PGI2 and NO) via cyclic nucleotides. In this review, we discuss: (1) GJ structure and regulation; (2) second messenger regulation of GJ phosphorylation and formation; (3) pregnancy-induced changes in cell-signaling; and (4) the role of uterine arterial endothelial GJs during gestation. These topics integrate the current knowledge of this scientific field with interpretations and hypotheses regarding the vascular effects that are mediated by GJs and their relationship with vasodilatory vascular adaptations required for modulating the dramatic physiological rises in uteroplacental perfusion and blood flow observed during normal pregnancy. PMID:25015806

Temperature Response of Mesophyll Conductance. Implications for the Determination of Rubisco Enzyme Kinetics and for Limitations to Photosynthesis in Vivo

PubMed Central

Bernacchi, Carl J.; Portis, Archie R.; Nakano, Hiromi; von Caemmerer, Susanne; Long, Stephen P.

2002-01-01

CO2 transfer conductance from the intercellular airspaces of the leaf into the chloroplast, defined as mesophyll conductance (gm), is finite. Therefore, it will limit photosynthesis when CO2 is not saturating, as in C3 leaves in the present atmosphere. Little is known about the processes that determine the magnitude of gm. The process dominating gm is uncertain, though carbonic anhydrase, aquaporins, and the diffusivity of CO2 in water have all been suggested. The response of gm to temperature (10°C–40°C) in mature leaves of tobacco (Nicotiana tabacum L. cv W38) was determined using measurements of leaf carbon dioxide and water vapor exchange, coupled with modulated chlorophyll fluorescence. These measurements revealed a temperature coefficient (Q10) of approximately 2.2 for gm, suggesting control by a protein-facilitated process because the Q10 for diffusion of CO2 in water is about 1.25. Further, gm values are maximal at 35°C to 37.5°C, again suggesting a protein-facilitated process, but with a lower energy of deactivation than Rubisco. Using the temperature response of gm to calculate CO2 at Rubisco, the kinetic parameters of Rubisco were calculated in vivo from 10°C to 40°C. Using these parameters, we determined the limitation imposed on photosynthesis by gm. Despite an exponential rise with temperature, gm does not keep pace with increased capacity for CO2 uptake at the site of Rubisco. The fraction of the total limitations to CO2 uptake within the leaf attributable to gm rose from 0.10 at 10°C to 0.22 at 40°C. This shows that transfer of CO2 from the intercellular air space to Rubisco is a very substantial limitation on photosynthesis, especially at high temperature. PMID:12481082

Maintenance of Air in Intercellular Spaces of Plants

PubMed Central

Woolley, Joseph T.

1983-01-01

Although air-filled intercellular spaces are necessary and ubiquitous in higher plants, little attention has been paid to the possible mechanisms by which these spaces are kept from being flooded. The most likely mechanism is that the living plant cell may maintain a hydrophobic monolayer on the surfaces of adjacent intercellular spaces. The existence of `apparent free space' in cell walls and the fact that detergent solutions do not enter the intercellular spaces argue against this hypothesis. It is concluded that the mechanism by which these important air spaces are maintained is still unknown. Images Fig. 1 Fig. 2 PMID:16663150

Release of Applied Mechanical Loading Stimulates Intercellular Calcium Waves in Drosophila Wing Discs.

PubMed

Narciso, Cody E; Contento, Nicholas M; Storey, Thomas J; Hoelzle, David J; Zartman, Jeremiah J

2017-07-25

Mechanical forces are critical but poorly understood inputs for organogenesis and wound healing. Calcium ions (Ca 2+ ) are critical second messengers in cells for integrating environmental and mechanical cues, but the regulation of Ca 2+ signaling is poorly understood in developing epithelial tissues. Here we report a chip-based regulated environment for microorgans that enables systematic investigations of the crosstalk between an organ's mechanical stress environment and biochemical signaling under genetic and chemical perturbations. This method enabled us to define the essential conditions for generating organ-scale intercellular Ca 2+ waves in Drosophila wing discs that are also observed in vivo during organ development. We discovered that mechanically induced intercellular Ca 2+ waves require fly extract growth serum as a chemical stimulus. Using the chip-based regulated environment for microorgans, we demonstrate that not the initial application but instead the release of mechanical loading is sufficient, but not necessary, to initiate intercellular Ca 2+ waves. The Ca 2+ response depends on the prestress intercellular Ca 2+ activity and not on the magnitude or duration of the mechanical stimulation applied. Mechanically induced intercellular Ca 2+ waves rely on IP 3 R-mediated Ca 2+ -induced Ca 2+ release and propagation through gap junctions. Thus, intercellular Ca 2+ waves in developing epithelia may be a consequence of stress dissipation during organ growth. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Development of a green fluorescent protein metastatic-cancer chick-embryo drug-screen model.

PubMed

Bobek, Vladimir; Plachy, Jiri; Pinterova, Daniela; Kolostova, Katarina; Boubelik, Michael; Jiang, Ping; Yang, Meng; Hoffman, Robert M

2004-01-01

The chick-embryo model has been an important tool to study tumor growth, metastasis, and angiogenesis. However, an imageable model with a genetic fluorescent tag in the growing and spreading cancer cells that is stable over time has not been developed. We report here the development of such an imageable fluorescent chick-embryo metastatic cancer model with the use of green fluorescent protein (GFP). Lewis lung carcinoma cells, stably expressing GFP, were injected on the 12th day of incubation in the chick embryo. GFP-Lewis lung carcinoma metastases were visualized by fluorescence, after seven days additional incubation, in the brain, heart, and sternum of the developing chick embryo, with the most frequent site being the brain. The combination of streptokinase and gemcitabine was evaluated in this GFP metastatic model. Twelve-day-old chick embryos were injected intravenously with GFP-Lewis lung cancer cells, along with these two agents either alone or in combination. The streptokinase-gemcitabine combination inhibited metastases at all sites. The effective dose of gemcitabine was found to be 10 mg/kg and streptokinase 2000 IU per embryo. The data in this report suggest that this new stably fluorescent imageable metastatic-cancer chick-embryo model will enable rapid screening of new antimetastatic agents.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Su Jin; New Drug Development Center, Osong Medical Innovation Foundation, Cheongwon, Chungbuk; Chang, Suhwan

Highlights: • PMAb83, a human monoclonal antibody against PAUF, impaired tumor progression in vivo. • PMAb83 attenuated aggressiveness of tumor cells and suppressed angiogenesis. • PMAb83 in combination with gemcitabine conferred improved survival of mouse model. - Abstract: Pancreatic adenocarcinoma up-regulated factor (PAUF) is expressed in pancreatic ductal adenocarcinoma (PDAC) and plays an important role in tumor progression and metastasis. Here we evaluate the anti-tumor efficacy of a human monoclonal antibody against PAUF, PMAb83, to provide a therapeutic intervention to treat the disease. PMAb83 reduced tumor growth and distant metastasis in orthotopically xenografted mice of human PDAC cells. PMAb83 treatmentmore » retarded proliferation along with weakened aggressiveness traits of the carcinoma cells. AKT/β-catenin signaling played a role in the carcinoma cell proliferation and the treated xenograft tumors exhibited reduced levels of β-catenin and cyclin D1. Moreover PMAb83 abrogated the PAUF-induced angiogenic responses of endothelial cells, reducing the density of CD31{sup +} vessels in the treated tumors. In combination with gemcitabine, PMAb83 conferred enhanced survival of xenografted mice by about twofold compared to gemcitabine alone. Taken together, our findings show that PMAb83 treatment decreases the aggressiveness of carcinoma cells and suppresses tumor vascularization, which culminates in mitigated tumor growth and metastasis with improved survival in PDAC mouse models.« less

[A case of gastric metastasis and carcinomatous peritonitis of breast cancer with improved QOL by stent implantation and gemcitabine].

PubMed

Mukaibashi, Tomoe; Kojima, Izumi; Yamanaka, Ayumi; Nishiyama, Sachiko; Yamanaka, Takashi; Nakayama, Hirotaka; Matsuura, Hitoshi; Matsuzu, Kenichi; Inaba, Masaaki; Yoshida, Akira; Shimizu, Satoru

2013-08-01

A 73-year-old woman had undergone mastectomy for left breast cancer. One year later, bone metastasis was detected. After 7 years, the patient experienced epigastric discomfort, and gastrointestinal endoscopy showed stenosis of the pylorus and enlarged gastric folds. Stomach cancer was suspected at first, but gastric metastasis of breast cancer was diagnosed on the basis of endoscopic reexamination and computed tomography(CT)images. The patient could not drink water, and therefore, gastrointestinal stenting was performed, which facilitated ingestion to some extent. However, at the same time, an elevated serum carcinoembryonic antigen(CEA)level and jaundice were observed. Therefore, biliary tract stenosis due to carcinomatous peritonitis was diagnosed. We attempted to treat the jaundice with endoscopic retrograde cholangiopancreatography( ERCP)or percutaneous transhepatic cholangiography(PTCD), but the treatment was not successful, and an increase in ascites was noted. Accordingly, gemcitabine was administered as systemic therapy. As a result, ascites decreased and jaundice improved. Patients with gastric metastasis of breast cancer have poor quality of life(QOL)because of difficulties in ingestion or vomiting, and poor prognoses, because of frequent concurrent carcinomatous peritonitis. We experienced a case of gastric metastasis and carcinomatous peritonitis, and were able to improve the patient's QOL by gastrointestinal stenting and gemcitabine administration.

The combination of i-leader truncation and gemcitabine improves oncolytic adenovirus efficacy in an immunocompetent model.

PubMed

Puig-Saus, C; Laborda, E; Rodríguez-García, A; Cascalló, M; Moreno, R; Alemany, R

2014-02-01

Adenovirus (Ad) i-leader protein is a small protein of unknown function. The C-terminus truncation of the i-leader protein increases Ad release from infected cells and cytotoxicity. In the current study, we use the i-leader truncation to enhance the potency of an oncolytic Ad. In vitro, an i-leader truncated oncolytic Ad is released faster to the supernatant of infected cells, generates larger plaques, and is more cytotoxic in both human and Syrian hamster cell lines. In mice bearing human tumor xenografts, the i-leader truncation enhances oncolytic efficacy. However, in a Syrian hamster pancreatic tumor model, which is immunocompetent and less permissive to human Ad, antitumor efficacy is only observed when the i-leader truncated oncolytic Ad, but not the non-truncated version, is combined with gemcitabine. This synergistic effect observed in the Syrian hamster model was not seen in vitro or in immunodeficient mice bearing the same pancreatic hamster tumors, suggesting a role of the immune system in this synergism. These results highlight the interest of the i-leader C-terminus truncation because it enhances the antitumor potency of an oncolytic Ad and provides synergistic effects with gemcitabine in the presence of an immune competent system.

INHIBITION OF GAP JUNCTIONAL INTERCELLULAR COMMUNICATION BY PERFLUORINATED COMPOUNDS IN RAT LIVER AND DOLPHIN KIDNEY EPITHELIAL CELL LINES IN VITRO AND SPRAGUE-DAWLEY RATS IN VIVO

EPA Science Inventory

Abstract

Gap Junctional Intercellular Communication (GJIC) is the major pathway of intercellular signal transduction, and is, thus, important for normal cell growth and function. Recent studies have revealed a global distribution of some perfluorinated organic compounds e...

Shared features of S100B immunohistochemistry and cytochrome oxidase histochemistry in the ventroposterior thalamus and lateral habenula in neonatal rats.

PubMed

Muneoka, Katsumasa; Funahashi, Hisayuki; Ogawa, Tetsuo; Whitaker-Azmitia, Patricia M; Shioda, Seiji

2012-10-01

The ventroposterior thalamus and the habenular nuclei of the epithalamus are relevant to the monoaminergic system functionally and anatomically. The glia-derived S100B protein plays a critical role in the development of the nervous system including the monoaminergic systems. In this study, we performed an immunohistochemical study of glia-related proteins including S100B, serotonin transporter, and microtubule-associated protein 2, as well as cytochrome oxidase histochemistry in neonatal rats. Results showed the same findings for S100B immunohistochemistry between the ventroposterior thalamus and the lateral habenula at postnatal day 7: intense staining in cell bodies of astrocytes, diffusely spread immunoproduct in the intercellular space, and S100B-free areas as well as a strong reaction to cytochrome oxidase histochemistry. Further common features were the scarcity of glial fibrillary acidic protein-positive astrocytes and the few apoptotic cells observed. The results of the cytochrome oxidase reaction suggested that S100B is released actively into intercellular areas in restricted brain regions showing high neuronal activity at postnatal day 7. Pathology of the ventroposterior thalamus and the habenula is suggested in mental disorders, and S100B might be a key factor for investigations in these areas. Copyright © 2012 ISDN. Published by Elsevier Ltd. All rights reserved.

Gemcitabine, Fludarabine, and Melphalan for Reduced-Intensity Conditioning and Allogeneic Stem Cell Transplantation for Relapsed and Refractory Hodgkin Lymphoma.

PubMed

Anderlini, Paolo; Saliba, Rima M; Ledesma, Celina; Plair, Tamera; Alousi, Amin M; Hosing, Chitra M; Khouri, Issa F; Nieto, Yago; Popat, Uday R; Shpall, Elizabeth J; Fanale, Michelle A; Hagemeister, Frederick B; Oki, Yasuhiro; Neelapu, Saatva; Romaguera, Jorge E; Younes, Anas; Champlin, Richard E

2016-07-01

Forty patients (median age, 31 years; range, 20 to 63) with Hodgkin lymphoma underwent an allogeneic stem cell transplant with the gemcitabine-fludarabine-melphalan reduced-intensity conditioning regimen. Thirty-one patients (77%) had undergone a prior autologous stem cell transplant, with a median time to progression after transplant of 6 months (range, 1 to 68). Disease status at transplant was complete remission/complete remission, undetermined (n = 23; 57%), partial remission (n = 14; 35%), and other (n = 3; 8%). Twenty-six patients (65%) received brentuximab vedotin before allotransplant. The overall complete response rate before allotransplant was 65% in brentuximab-treated patients versus 42% in brentuximab-naive patients (P = .15). At the latest follow-up (October 2015) 31 patients were alive. The median follow-up was 41 months (range, 5 to 87). Transplant-related mortality rate at 3 years was 17%. Pulmonary, skin toxicities, and nausea were seen in 13 (33%), 11 (28%), and 37 (93%) patients, respectively. At 3 years, estimates for overall and progression-free survival were 75% (95% CI, 57% to 86%) and 54% (95% CI, 36% to 70%). Overall incidence for disease progression was 28% (95% CI, 16% to 50%). We believe the gemcitabine-fludarabine-melphalan regimen allows moderate dose intensification with acceptable morbidity and mortality. The inclusion of gemcitabine affected nausea, pulmonary, and likely skin toxicity. Exposure to brentuximab vedotin allowed more patients to reach allogeneic stem cell transplantation in complete remission. With over 50% of patients progression-free at 3 years, allogeneic stem cell transplantation with reduced-intensity conditioning remains an effective and relevant treatment option for Hodgkin lymphoma in the brentuximab vedotin era. Copyright © 2016 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

CKD-516 displays vascular disrupting properties and enhances anti-tumor activity in combination with chemotherapy in a murine tumor model.

PubMed

Moon, Chang Hoon; Lee, Seung Ju; Lee, Ho Yong; Dung, Le Thi Kim; Cho, Wha Ja; Cha, HeeJeong; Park, Jeong Woo; Min, Young Joo

2014-06-01

CKD-516 is a benzophenone analog in which the B ring is modified by replacement with a carbonyl group. The study assessed CKD-516 as a vascular disrupting agent or anti-cancer drug. To assess the effect of S516 on vascularization, we analyzed the effect on human umbilical vein endothelial cells (HUVECs). To determine the inhibition of cell proliferation of S516, we used H460 lung carcinoma cells. The alteration of microtubules was analyzed using immunoblot, RT-PCR and confocal imaging. To evaluate the anti-tumor effects of gemcitabine and/or CKD-516, H460 xenograft mice were treated with CKD-516 (2.5 mg/kg) and/or gemcitabine (40 mg/kg), and tumor growth was compared with vehicle-treated control. For histologic analysis, liver, spleen and tumor tissues from H460 xenograft mice were obtained 12 and 24 h after CKD-516 injection. Cytoskeletal changes of HUVECs treated with 10 nM S516 were assessed by immunoblot and confocal imaging. S516 disrupted tubulin assembly and resulted in microtubule dysfunction, which induced cell cycle arrest (G2/M). S516 markedly enhanced the depolymerization of microtubules, perhaps due to the vascular disrupting properties of S516. Interestingly, S516 decreased the amount of total tubulin protein in HUVECs. Especially, S516 decreased mRNA expression α-tubulin (HUVECs only) and β-tubulin (HUVECs and H460 cells) at an early time point (4 h). Immunocytochemical analysis showed that S516 changed the cellular microtubule network and inhibited the formation of polymerized microtubules. Extensive central necrosis of tumors was evident by 12 h after treatment with CKD-516 (2.5 mg/kg, i.p.). In H460 xenografts, CKD-516 combined with gemcitabine significantly delayed tumor growth up to 57 % and 36 % as compared to control and gemcitabine alone, respectively. CKD-516 is a novel agent with vascular disrupting properties and enhances anti-tumor activity in combination with chemotherapy.

Complete response in gallbladder cancer to erlotinib plus gemcitabine does not require mutation of the epidermal growth factor receptor gene: a case report.

PubMed

Mody, Kabir; Strauss, Edward; Lincer, Robert; Frank, Richard C

2010-10-20

Gallbladder cancer typically follows an aggressive course, with chemotherapy the standard of care for advanced disease; complete remissions are rarely encountered. The epidermal growth factor receptor (EGFR) is a promising therapeutic target but the activity of single agent oral EGFR tyrosine kinase inhibitors is low. There have been no previous reports of chemotherapy plus an EGFR-tyrosine kinase inhibitor (TKI) to treat gallbladder cancer or correlations of response with the mutation status of the tyrosine kinase domain of the EGFR gene. A 67 year old man with metastatic gallbladder cancer involving the liver and abdominal lymph nodes was treated with gemcitabine (1000 mg/m2) on day 1 and 8 every 21 days as well as daily erlotinib (100 mg). After four cycles of therapy, the CA 19-9 normalized and a PET/CT showed a complete remission; this response was maintained by the end of 12 cycles of therapy. Gemcitabine was then discontinued and single agent erlotinib was continued as maintenance therapy. The disease remains in good control 18 months after initiation of therapy, including 6 months on maintenance erlotinib. The only grade 3 toxicity was a typical EGFR-related skin rash. Because of the remarkable response to erlotinib plus gemcitabine, we performed tumor genotyping of the EGFR gene for response predicting mutations in exons 18, 19 and 21. This disclosed the wild-type genotype with no mutations found. This case report demonstrates a patient with stage IV gallbladder cancer who experienced a rarely encountered complete, prolonged response after treatment with an oral EGFR-TKI plus chemotherapy. This response occurred in the absence of an EGFR gene mutation. These observations should inform the design of clinical trials using EGFR-TKIs to treat gallbladder and other biliary tract cancers; such trials should not select patients based on EGFR mutation status.

Gemcitabine and carboplatin in advanced transitional cell carcinoma of the urinary tract: an alternative therapy.

PubMed

Nogué-Aliguer, Miquel; Carles, Joan; Arrivi, Antonio; Juan, Oscar; Alonso, Lorenzo; Font, Albert; Mellado, Begoña; Garrido, Pilar; Sáenz, Alberto

2003-05-01

Cisplatin-based combinations are considered to be the standard treatment for advanced transitional cell carcinoma (TCC) of the urothelium. Many of the patients are elderly with concomitant diseases or impaired renal function. We studied the tolerance and activity of the gemcitabine/carboplatin combination as a therapeutic alternative. Patients with locally advanced or metastatic TCC of the urothelium were treated with gemcitabine 1000 mg/m(2) on Days 1 and 8 and carboplatin area under the concentration-time curve 5 on Day 1 every 21 days. Patients with creatinine clearance of 30 mL/min or above and Karnofsky performance status (KPS) scores 60 or above were enrolled. A total of 227 cycles were administered to 41 patients, with an average of 5.5 cycles per patient (range, 1-8 cycles). Creatinine clearance was below 60 mL/min in 54% of patients, KPS was 70 or below in 37% of patients, and 37% of patients were 70 years old or older. Hematologic toxicity was mainly Grade 3/4 neutropenia in 63%, Grade 3/4 thrombocytopenia in 32%, and Grade 3/4 anemia in 54% of patients. There were only three episodes of febrile neutropenia and one death from neutropenic sepsis. Nonhematologic toxicity was mild, with asthenia as the most frequently reported event. We obtained 6 complete and 17 partial responses, for an overall response rate of 56.1% (95% confidence interval [CI], 40.6-71.6%). Progression-free survival was 7.2 months (95% CI, 5.7-8.5) and median survival was 10.1 months (95% CI, 8.8-12.2). The combination of gemcitabine plus carboplatin achieves a similar result to doublets using cisplatin. It has an acceptable toxicity profile and enables patients with impaired renal function and/or poor performance status and elderly patients to be treated. Copyright 2003 American Cancer Society.DOI 10.1002/cncr.10990

The FAK scaffold inhibitor C4 disrupts FAK-VEGFR-3 signaling and inhibits pancreatic cancer growth

PubMed Central

Kurenova, Elena; Liao, Jianqun; He, Di-Hua; Hunt, Darrell; Yemma, Michael; Bshara, Wiam; Seshadri, Mukund; Cance, William G.

2013-01-01

Even with successful surgical resection and perioperative chemotherapy and radiation, pancreatic ductal adenocarcinoma (PDA) has a high incidence of recurrence. Tumor cell survival depends on activation of signaling pathways that suppress the apoptotic stimuli of invasion and metastasis. Focal adhesion kinase (FAK) is a critical signaling molecule that has been implicated in tumor cell survival, invasion and metastasis. We have previously shown that FAK and vascular endothelial growth factor receptor 3 (VEGFR-3) are overexpressed in cancer cells and physically interact to confer a significant survival advantage. We subsequently identified a novel small molecule inhibitor C4 that targeted the VEGFR-3-FAK site of interaction. In this study, we have shown that C4 disrupted the FAK-VEGFR-3 complexes in PDA cells. C4 treatment caused dose-dependent dephosphorylation and inactivation of the VEGFR-3 and FAK, reduction in cell viability and proliferation, cell cycle arrest and apoptosis in PDA cells. C4 increased the sensitivity of tumor cells to gemcitabine chemotherapy in vitro that lead to apoptosis at nanomolar concentrations of both drugs. C4 reduced tumor growth in vivoin subcutaneous and orthotopic murine models of PDA. The drug alone at low dose, decreased tumor growth; however, concomitant administration with low dose of gemcitabine had significant synergistic effect and led to 70% tumor reduction. Combination of C4 with gemcitabine had a prolonged cytostatic effect on tumor growth after treatment withdrawal. Finally, we report an anecdotal case of stage IV pancreatic cancer treated with gemcitabine in combination with C4 that showed a significant clinical response in primary tumor and complete clinical response in liver metastasis over an eight month period. Taken together, these results demonstrate that targeting the scaffolding function of FAK with a small-molecule FAK-VEGFR-3 inhibitor can be an effective therapeutic strategy against PDA. PMID:24142503

Phase I trial of gefitinib with concurrent radiotherapy and fixed 2-h gemcitabine infusion, in locally advanced pancreatic cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maurel, Joan; Martin-Richard, Marta; Conill, Carlos

Purpose: Pancreatic cancers are resistant to radiotherapy (RT) and current chemotherapy agents. Epidermal growth factor receptor is overexpressed in pancreatic cancer, and in vitro studies have shown that epidermal growth factor receptor inhibitors can overcome radio- and chemoresistance. The aim of the study was to determine whether the addition of gefitinib to RT and gemcitabine for patients with locally advanced pancreatic carcinoma (LAPC) was feasible and safe. Methods and Materials: Eighteen patients with pathologically proven LAPC, based on major vascular invasion based on helical computed tomography (CT) and endoscopic ultrasound, were entered into the study. The targeted irradiated volume includedmore » the tumor and 2-cm margin. Prophylactic irradiation of regional nodes was not allowed. Patients with >500 cm{sup 3} of planning tumor volume were excluded. An initial cohort of 6 patients was treated with RT (45 Gy/25 fractions/5 weeks) plus concomitant gefitinib (250 mg/day). Successive cohorts of patients received 100, 150, and 200 mg/m{sup 2}/day of gemcitabine in a 2-h infusion over Weeks 1, 2, 3, 4, and 5 with gefitinib (250 mg/day) and RT. Gefitinib was continued after RT until progression. A pharmacodynamic study of angiogenic markers was also performed to evaluate a possible antiangiogenic effect. Results: There were no dose-limiting toxicities. Common toxicities were mild neutropenia, asthenia, diarrhea, cutaneous rash and nausea/vomiting. The median (95% confidence interval [CI]) progression-free survival was 3.7 (95% CI = 1.9-5.5) months, and the median overall survival was 7.5 (95% CI 5.2-9.9) months. No significant reduction of vascular endothelial growth factor and interleukin-8 was observed after treatment. Conclusion: Our results support that the combination of gefitinib, RT, and gemcitabine has an acceptable toxicity but with modest activity in LAPC.« less

The vascular plant-pathogenic bacterium Ralstonia solanacearum produces biofilms required for its virulence on the surfaces of tomato cells adjacent to intercellular spaces.

PubMed

Mori, Yuka; Inoue, Kanako; Ikeda, Kenichi; Nakayashiki, Hitoshi; Higashimoto, Chikaki; Ohnishi, Kouhei; Kiba, Akinori; Hikichi, Yasufumi

2016-08-01

The mechanism of colonization of intercellular spaces by the soil-borne and vascular plant-pathogenic bacterium Ralstonia solanacearum strain OE1-1 after invasion into host plants remains unclear. To analyse the behaviour of OE1-1 cells in intercellular spaces, tomato leaves with the lower epidermis layers excised after infiltration with OE1-1 were observed under a scanning electron microscope. OE1-1 cells formed microcolonies on the surfaces of tomato cells adjacent to intercellular spaces, and then aggregated surrounded by an extracellular matrix, forming mature biofilm structures. Furthermore, OE1-1 cells produced mushroom-type biofilms when incubated in fluids of apoplasts including intercellular spaces, but not xylem fluids from tomato plants. This is the first report of biofilm formation by R. solanacearum on host plant cells after invasion into intercellular spaces and mushroom-type biofilms produced by R. solanacearum in vitro. Sugar application led to enhanced biofilm formation by OE1-1. Mutation of lecM encoding a lectin, RS-IIL, which reportedly exhibits affinity for these sugars, led to a significant decrease in biofilm formation. Colonization in intercellular spaces was significantly decreased in the lecM mutant, leading to a loss of virulence on tomato plants. Complementation of the lecM mutant with native lecM resulted in the recovery of mushroom-type biofilms and virulence on tomato plants. Together, our findings indicate that OE1-1 produces mature biofilms on the surfaces of tomato cells after invasion into intercellular spaces. RS-IIL may contribute to biofilm formation by OE1-1, which is required for OE1-1 virulence. © 2015 BSPP AND JOHN WILEY & SONS LTD.

Oesophageal mucosal intercellular space diameter and reflux pattern in childhood erosive and non-erosive reflux disease.

PubMed

Mancini, Valentina; Ribolsi, Mentore; Gentile, Massimo; de'Angelis, Gianluigi; Bizzarri, Barbara; Lindley, Keith J; Cucchiara, Salvatore; Cicala, Michele; Borrelli, Osvaldo

2012-12-01

We sought to compare intercellular space diameter in children with non-erosive and erosive reflux disease, and a control group. We also aimed to characterize the reflux pattern in erosive and non-erosive reflux disease patients, and to explore the relationship between intercellular space diameter values and reflux parameters. Twenty-four children with non-erosive reflux disease, 20 with erosive reflux disease, and 10 controls were prospectively studied. All patients and controls underwent upper endoscopy. Biopsies were taken at 2-3 cm above the Z-line, and intercellular space diameter was measured using transmission electron microscopy. Non-erosive and erosive reflux disease patients underwent impedance-pH monitoring. Mean intercellular space diameter values were significantly higher in both non-erosive (0.9 ± 0.2 μm) and erosive reflux disease (1 ± 0.2 μm) compared to controls (0.5 ± 0.2 μm, p<0.01). No difference was found between the two patient groups. Acid exposure time, the number of acid, weakly acidic and weakly alkaline reflux events did not differ between the two patient groups. No difference was found in the mean intercellular space diameter between non-erosive reflux disease children with and without abnormal acid exposure time (1 ± 0.3 vs. 0.9 ± 0.2 μm). No correlation was found between any reflux parameter and intercellular space diameter values. Dilated intercellular space diameter seems to be a useful and objective marker of oesophageal damage in paediatric gastro-oesophageal reflux disease, regardless of acid exposure. In childhood, different gastro-oesophageal reflux disease phenotypes cannot be discriminated on the basis of reflux pattern. Copyright © 2012 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

Intercellular and systemic spread of RNA and RNAi in plants.

PubMed

Nazim Uddin, Mohammad; Kim, Jae-Yean

2013-01-01

Plants possess dynamic networks of intercellular communication that are crucial for plant development and physiology. In plants, intercellular communication involves a combination of ligand-receptor-based apoplasmic signaling, and plasmodesmata and phloem-mediated symplasmic signaling. The intercellular trafficking of macromolecules, including RNAs and proteins, has emerged as a novel mechanism of intercellular communication in plants. Various forms of regulatory RNAs move over distinct cellular boundaries through plasmodesmata and phloem. This plant-specific, non-cell-autonomous RNA trafficking network is also involved in development, nutrient homeostasis, gene silencing, pathogen defense, and many other physiological processes. However, the mechanism underlying macromolecular trafficking in plants remains poorly understood. Current progress made in RNA trafficking research and its biological relevance to plant development will be summarized. Diverse plant regulatory mechanisms of cell-to-cell and systemic long-distance transport of RNAs, including mRNAs, viral RNAs, and small RNAs, will also be discussed. Copyright © 2013 John Wiley & Sons, Ltd.

Estimating intercellular surface tension by laser-induced cell fusion.

PubMed

Fujita, Masashi; Onami, Shuichi

2011-12-01

Intercellular surface tension is a key variable in understanding cellular mechanics. However, conventional methods are not well suited for measuring the absolute magnitude of intercellular surface tension because these methods require determination of the effective viscosity of the whole cell, a quantity that is difficult to measure. In this study, we present a novel method for estimating the intercellular surface tension at single-cell resolution. This method exploits the cytoplasmic flow that accompanies laser-induced cell fusion when the pressure difference between cells is large. Because the cytoplasmic viscosity can be measured using well-established technology, this method can be used to estimate the absolute magnitudes of tension. We applied this method to two-cell-stage embryos of the nematode Caenorhabditis elegans and estimated the intercellular surface tension to be in the 30-90 µN m(-1) range. Our estimate was in close agreement with cell-medium surface tensions measured at single-cell resolution.

Gemcitabine, Oxaliplatin, Tarceva &/or Cisplatin in HCC & Biliary Tree Cancers

ClinicalTrials.gov

2018-06-27

Hepatocellular Carcinoma; Cholangiocellular Carcinoma; Cholangiocarcinoma of the Extrahepatic Bile Duct; Bile Duct Cancer; Periampullary Adenocarcinoma; Gallbladder Cancer; Extrahepatic Bile Duct Cancer

Multiscale modeling of transdermal drug delivery

NASA Astrophysics Data System (ADS)

Rim, Jee Eun

2006-04-01

This study addresses the modeling of transdermal diffusion of drugs, to better understand the permeation of molecules through the skin, and especially the stratum corneum, which forms the main permeation barrier of the skin. In transdermal delivery of systemic drugs, the drugs diffuse from a patch placed on the skin through the epidermis to the underlying blood vessels. The epidermis is the outermost layer of the skin and can be further divided into the stratum corneum (SC) and the viable epidermis layers. The SC consists of keratinous cells (corneocytes) embedded in the lipid multi-bilayers of the intercellular space. It is widely accepted that the barrier properties of the skin mostly arises from the ordered structure of the lipid bilayers. The diffusion path, at least for lipophilic molecules, seems to be mainly through the lipid bilayers. Despite the advantages of transdermal drug delivery compared to other drug delivery routes such as oral dosing and injections, the low percutaneous permeability of most compounds is a major difficulty in the wide application of transdermal drug delivery. In fact, many transdermal drug formulations include one or more permeation enhancers that increase the permeation of the drug significantly. During the last two decades, many researchers have studied percutaneous absorption of drugs both experimentally and theoretically. However, many are based on pharmacokinetic compartmental models, in which steady or pseudo-steady state conditions are assumed, with constant diffusivity and partitioning for single component systems. This study presents a framework for studying the multi-component diffusion of drugs coupled with enhancers through the skin by considering the microstructure of the stratum corneum (SC). A multiscale framework of modeling the transdermal diffusion of molecules is presented, by first calculating the microscopic diffusion coefficient in the lipid bilayers of the SC using molecular dynamics (MD). Then a homogenization procedure is performed over a model unit cell of the heterogeneous SC, resulting in effective diffusion parameters. These effective parameters are the macroscopic diffusion coefficients for the homogeneous medium that is "equivalent" to the heterogeneous SC, and thus can be used in finite element simulations of the macroscopic diffusion process.

Stomatal responses to flooding of the intercellular air spaces suggest a vapor-phase signal between the mesophyll and the guard cells.

PubMed

Sibbernsen, Erik; Mott, Keith A

2010-07-01

Flooding the intercellular air spaces of leaves with water was shown to cause rapid closure of stomata in Tradescantia pallida, Lactuca serriola, Helianthus annuus, and Oenothera caespitosa. The response occurred when water was injected into the intercellular spaces, vacuum infiltrated into the intercellular spaces, or forced into the intercellular spaces by pressurizing the xylem. Injecting 50 mm KCl or silicone oil into the intercellular spaces also caused stomata to close, but the response was slower than with distilled water. Epidermis-mesophyll grafts for T. pallida were created by placing the epidermis of one leaf onto the exposed mesophyll of another leaf. Stomata in these grafts opened under light but closed rapidly when water was allowed to wick between epidermis and the mesophyll. When epidermis-mesophyll grafts were constructed with a thin hydrophobic filter between the mesophyll and epidermis stomata responded normally to light and CO(2). These data, when taken together, suggest that the effect of water on stomata is caused partly by dilution of K(+) in the guard cell and partly by the existence of a vapor-phase signal that originates in the mesophyll and causes stomata to open in the light.

Investigating plasmodesmata genetics with virus-induced gene silencing and an agrobacterium-mediated GFP movement assay.

PubMed

Brunkard, Jacob O; Burch-Smith, Tessa M; Runkel, Anne M; Zambryski, Patricia

2015-01-01

Plasmodesmata (PD) are channels that connect the cytoplasm of adjacent plant cells, permitting intercellular transport and communication. PD function and formation are essential to plant growth and development, but we still know very little about the genetic pathways regulating PD transport. Here, we present a method for assaying changes in the rate of PD transport following genetic manipulation. Gene expression in leaves is modified by virus-induced gene silencing. Seven to ten days after infection with Tobacco rattle virus carrying a silencing trigger, the gene(s) of interest is silenced in newly arising leaves. In these new leaves, individual cells are then transformed with Agrobacterium to express GFP, and the rate of GFP diffusion via PD is measured. By measuring GFP diffusion both within the epidermis and between the epidermis and mesophyll, the assay can be used to study the effects of silencing a gene(s) on PD transport in general, or transport through secondary PD specifically. Plant biologists working in several fields will find this assay useful, since PD transport impacts plant physiology, development, and defense.

Innexin-3 forms connexin-like intercellular channels.

PubMed

Landesman, Y; White, T W; Starich, T A; Shaw, J E; Goodenough, D A; Paul, D L

1999-07-01

Innexins comprise a large family of genes that are believed to encode invertebrate gap junction channel-forming proteins. However, only two Drosophila innexins have been directly tested for the ability to form intercellular channels and only one of those was active. Here we tested the ability of Caenorhabditis elegans family members INX-3 and EAT-5 to form intercellular channels between paired Xenopus oocytes. We show that expression of INX-3 but not EAT-5, induces electrical coupling between the oocyte pairs. In addition, analysis of INX-3 voltage and pH gating reveals a striking degree of conservation in the functional properties of connexin and innnexin channels. These data strongly support the idea that innexin genes encode intercellular channels.

Pancreatic adenocarcinoma response to chemotherapy enhanced with non-invasive radio frequency evaluated via an integrated experimental/computational approach.

PubMed

Ware, Matthew J; Curtis, Louis T; Wu, Min; Ho, Jason C; Corr, Stuart J; Curley, Steven A; Godin, Biana; Frieboes, Hermann B

2017-06-13

Although chemotherapy combined with radiofrequency exposure has shown promise in cancer treatment by coupling drug cytotoxicity with thermal ablation or thermally-induced cytotoxicity, limited access of the drug to tumor loci in hypo-vascularized lesions has hampered clinical application. We recently showed that high-intensity short-wave capacitively coupled radiofrequency (RF) electric-fields may reach inaccessible targets in vivo. This non-invasive RF combined with gemcitabine (Gem) chemotherapy enhanced drug uptake and effect in pancreatic adenocarcinoma (PDAC), notorious for having poor response and limited therapeutic options, but without inducing thermal injury. We hypothesize that the enhanced cytotoxicity derives from RF-facilitated drug transport in the tumor microenvironment. We propose an integrated experimental/computational approach to evaluate chemotherapeutic response combined with RF-induced phenotypic changes in tissue with impaired transport. Results show that RF facilitates diffusive transport in 3D cell cultures representing hypo-vascularized lesions, enhancing drug uptake and effect. Computational modeling evaluates drug vascular extravasation and diffusive transport as key RF-modulated parameters, with transport being dominant. Assessment of hypothetical schedules following current clinical protocol for Stage-IV PDAC suggests that unresponsive lesions may be growth-restrained when exposed to Gem plus RF. Comparison of these projections to experiments in vivo indicates that synergy may result from RF-induced cell phenotypic changes enhancing drug transport and cytotoxicity, thus providing a potential baseline for clinically-focused evaluation.

Mesophyll conductance and reaction-diffusion models for CO2 transport in C3 leaves; needs, opportunities and challenges.

PubMed

Berghuijs, Herman N C; Yin, Xinyou; Ho, Q Tri; Driever, Steven M; Retta, Moges A; Nicolaï, Bart M; Struik, Paul C

2016-11-01

One way to increase potential crop yield could be increasing mesophyll conductance g m . This variable determines the difference between the CO 2 partial pressure in the intercellular air spaces (C i ) and that near Rubisco (C c ). Various methods can determine g m from gas exchange measurements, often combined with measurements of chlorophyll fluorescence or carbon isotope discrimination. g m lumps all biochemical and physical factors that cause the difference between C c and C i . g m appears to vary with C i . This variability indicates that g m does not satisfy the physical definition of a conductance according to Fick's first law and is thus an apparent parameter. Uncertainty about the mechanisms that determine g m can be limited to some extent by using analytical models that partition g m into separate conductances. Such models are still only capable of describing the CO 2 diffusion pathway to a limited extent, as they make implicit assumptions about the position of mitochondria in the cells, which affect the re-assimilation of (photo)respired CO 2 . Alternatively, reaction-diffusion models may be used. Rather than quantifying g m , these models explicitly account for factors that affect the efficiency of CO 2 transport in the mesophyll. These models provide a better mechanistic description of the CO 2 diffusion pathways than mesophyll conductance models. Therefore, we argue that reaction-diffusion models should be used as an alternative to mesophyll conductance models, in case the aim of such a study is to identify traits that can be improved to increase g m . Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Anatomical basis of variation in mesophyll resistance in eastern Australian sclerophylls: news of a long and winding path

PubMed Central

Tosens, Tiina

2012-01-01

In sclerophylls, photosynthesis is particularly strongly limited by mesophyll diffusion resistance from substomatal cavities to chloroplasts (r m), but the controls on diffusion limits by integral leaf variables such as leaf thickness, density, and dry mass per unit area and by the individual steps along the diffusion pathway are imperfectly understood. To gain insight into the determinants of r m in leaves with varying structure, the full CO2 physical diffusion pathway was analysed in 32 Australian species sampled from sites contrasting in soil nutrients and rainfall, and having leaf structures from mesophytic to strongly sclerophyllous. r m was estimated based on combined measurements of gas exchange and chlorophyll fluorescence. In addition, r m was modelled on the basis of detailed anatomical measurements to separate the importance of different serial resistances affecting CO2 diffusion into chloroplasts. The strongest sources of variation in r m were S c/S, the exposed surface area of chloroplasts per unit leaf area, and mesophyll cell wall thickness, t cw. The strong correlation of r m with t cw could not be explained by cell wall thickness alone, and most likely arose from a further effect of cell wall porosity. The CO2 drawdown from intercellular spaces to chloroplasts was positively correlated with t cw, suggesting enhanced diffusional limitations in leaves with thicker cell walls. Leaf thickness and density were poorly correlated with S c/S, indicating that widely varying combinations of leaf anatomical traits occur at given values of leaf integrated traits, and suggesting that detailed anatomical studies are needed to predict r m for any given species. PMID:22888123

Intercellular ultrafast Ca2+ wave in vascular smooth muscle cells: numerical and experimental study

NASA Astrophysics Data System (ADS)

Quijano, J. C.; Raynaud, F.; Nguyen, D.; Piacentini, N.; Meister, J. J.

2016-08-01

Vascular smooth muscle cells exhibit intercellular Ca2+ waves in response to local mechanical or KCl stimulation. Recently, a new type of intercellular Ca2+ wave was observed in vitro in a linear arrangement of smooth muscle cells. The intercellular wave was denominated ultrafast Ca2+ wave and it was suggested to be the result of the interplay between membrane potential and Ca2+ dynamics which depended on influx of extracellular Ca2+, cell membrane depolarization and its intercel- lular propagation. In the present study we measured experimentally the conduction velocity of the membrane depolarization and performed simulations of the ultrafast Ca2+ wave along coupled smooth muscle cells. Numerical results reproduced a wide spectrum of experimental observations, including Ca2+ wave velocity, electrotonic membrane depolarization along the network, effects of inhibitors and independence of the Ca2+ wave speed on the intracellular stores. The numerical data also provided new physiological insights suggesting ranges of crucial model parameters that may be altered experimentally and that could significantly affect wave kinetics allowing the modulation of the wave characteristics experimentally. Numerical and experimental results supported the hypothesis that the propagation of membrane depolarization acts as an intercellular messenger mediating intercellular ultrafast Ca2+ waves in smooth muscle cells.

Stomatal Responses to Flooding of the Intercellular Air Spaces Suggest a Vapor-Phase Signal Between the Mesophyll and the Guard Cells1[OA

PubMed Central

Sibbernsen, Erik; Mott, Keith A.

2010-01-01

Flooding the intercellular air spaces of leaves with water was shown to cause rapid closure of stomata in Tradescantia pallida, Lactuca serriola, Helianthus annuus, and Oenothera caespitosa. The response occurred when water was injected into the intercellular spaces, vacuum infiltrated into the intercellular spaces, or forced into the intercellular spaces by pressurizing the xylem. Injecting 50 mm KCl or silicone oil into the intercellular spaces also caused stomata to close, but the response was slower than with distilled water. Epidermis-mesophyll grafts for T. pallida were created by placing the epidermis of one leaf onto the exposed mesophyll of another leaf. Stomata in these grafts opened under light but closed rapidly when water was allowed to wick between epidermis and the mesophyll. When epidermis-mesophyll grafts were constructed with a thin hydrophobic filter between the mesophyll and epidermis stomata responded normally to light and CO2. These data, when taken together, suggest that the effect of water on stomata is caused partly by dilution of K+ in the guard cell and partly by the existence of a vapor-phase signal that originates in the mesophyll and causes stomata to open in the light. PMID:20472750

An Italian cost-effectiveness analysis of paclitaxel albumin (nab-paclitaxel) + gemcitabine vs gemcitabine alone for metastatic pancreatic cancer patients: the APICE study.

PubMed

Lazzaro, Carlo; Barone, Carlo; Caprioni, Francesco; Cascinu, Stefano; Falcone, Alfredo; Maiello, Evaristo; Milella, Michele; Pinto, Carmine; Reni, Michele; Tortora, Giampaolo

2018-04-20

the APICE study evaluates the cost-effectiveness of nanoparticle albumin-bound paclitaxel (nab-paclitaxel - Nab-P) + gemcitabine (G) vs G alone in metastatic pancreatic cancer (MPC) from the Italian National Health Service (INHS) standpoint. A 4-year, 4 health states (progression-free; progressed; end of life; death) Markov model based on the MPACT trial was developed to estimate costs (Euro [€], 2017 values), and quality-adjusted life years (QALYs). Patients were assumed to receive intravenously Nab-P 125 mg/m 2  + G 1000 mg/m 2 on days 1, 8, and 15 every 4 weeks or G alone 1000 mg/m 2 weekly for 7 out of 8 weeks (cycle 1) and then on days 1, 8, and 15 every 4 weeks (cycle 2 and subsequent cycles) until progression. One-way and probabilistic sensitivity analyses explored the uncertainty surrounding the baseline incremental cost-utility ratio (ICUR). Nab-P + G totals 0.154 incremental QALYs and €7082.68 incremental costs vs G alone. ICUR (€46,021.58) is lower than the informal threshold value of €87,330 adopted by the Italian Medicines Agency during 2010-2013 for reimbursing oncological drugs. Sensitivity analyses confirmed the robustness of the baseline findings. Nab-P + G in MPC patients can be considered cost-effective for the INHS.

uPAR-controlled oncolytic adenoviruses eliminate cancer stem cells in human pancreatic tumors.

PubMed

Sobrevals, Luciano; Mato-Berciano, Ana; Urtasun, Nerea; Mazo, Adela; Fillat, Cristina

2014-01-01

Pancreatic tumors contain cancer stem cells highly resistant to chemotherapy. The identification of therapies that can eliminate this population of cells might provide with more effective treatments. In the current work we evaluated the potential of oncolytic adenoviruses to act against pancreatic cancer stem cells (PCSC). PCSC from two patient-derived xenograft models were isolated from orthotopic pancreatic tumors treated with saline, or with the chemotherapeutic agent gemcitabine. An enrichment in the number of PCSC expressing the cell surface marker CD133 and a marked enhancement on tumorsphere formation was observed in gemcitabine treated tumors. No significant increase in the CD44, CD24, and epithelial-specific antigen (ESA) positive cells was observed. Neoplastic sphere-forming cells were susceptible to adenoviral infection and exposure to oncolytic adenoviruses resulted in elevated cytotoxicity with both Adwt and the tumor specific AduPARE1A adenovirus. In vivo, intravenous administration of a single dose of AduPARE1A in human-derived pancreatic xenografts led to a remarkable anti-tumor effect. In contrast to gemcitabine AduPARE1A treatment did not result in PCSC enrichment. No enrichment on tumorspheres neither on the CD133(+) population was detected. Therefore our data provide evidences of the relevance of uPAR-controlled oncolytic adenoviruses for the elimination of pancreatic cancer stem cells. © 2013.

Knockdown of cullin 4A inhibits growth and increases chemosensitivity in lung cancer cells.

PubMed

Hung, Ming-Szu; Chen, I-Chuan; You, Liang; Jablons, David M; Li, Ya-Chin; Mao, Jian-Hua; Xu, Zhidong; Lung, Jr-Hau; Yang, Cheng-Ta; Liu, Shih-Tung

2016-07-01

Cullin 4A (Cul4A) has been observed to be overexpressed in various cancers. In this study, the role of Cul4A in the growth and chemosensitivity in lung cancer cells were studied. We showed that Cul4A is overexpressed in lung cancer cells and tissues. Knockdown of the Cul4A expression by shRNA in lung cancer cells resulted in decreased cellular proliferation and growth in lung cancer cells. Increased sensitivity to gemcitabine, a chemotherapy drug, was also noted in those Cul4A knockdown lung cancer cells. Moreover, increased expression of p21, transforming growth factor (TGF)-β inducible early gene-1 (TIEG1) and TGF beta-induced (TGFBI) was observed in lung cancer cells after Cul4A knockdown, which may be partially related to increased chemosensitivity to gemcitabine. G0/G1 cell cycle arrest was also noted after Cul4A knockdown. Notably, decreased tumour growth and increased chemosensitivity to gemcitabine were also noted after Cul4A knockdown in lung cancer xenograft nude mice models. In summary, our study showed that targeting Cul4A with RNAi or other techniques may provide a possible insight to the development of lung cancer therapy in the future. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

Stability-Indicating HPLC Determination of Gemcitabine in Pharmaceutical Formulations

PubMed Central

Singh, Rahul; Shakya, Ashok K.; Naik, Rajashri; Shalan, Naeem

2015-01-01

A simple, sensitive, inexpensive, and rapid stability indicating high performance liquid chromatographic method has been developed for determination of gemcitabine in injectable dosage forms using theophylline as internal standard. Chromatographic separation was achieved on a Phenomenex Luna C-18 column (250 mm × 4.6 mm; 5μ) with a mobile phase consisting of 90% water and 10% acetonitrile (pH 7.00 ± 0.05). The signals of gemcitabine and theophylline were recorded at 275 nm. Calibration curves were linear in the concentration range of 0.5–50 μg/mL. The correlation coefficient was 0.999 or higher. The limit of detection and limit of quantitation were 0.1498 and 0.4541 μg/mL, respectively. The inter- and intraday precision were less than 2%. Accuracy of the method ranged from 100.2% to 100.4%. Stability studies indicate that the drug was stable to sunlight and UV light. The drug gives 6 different hydrolytic products under alkaline stress and 3 in acidic condition. Aqueous and oxidative stress conditions also degrade the drug. Degradation was higher in the alkaline condition compared to other stress conditions. The robustness of the methods was evaluated using design of experiments. Validation reveals that the proposed method is specific, accurate, precise, reliable, robust, reproducible, and suitable for the quantitative analysis. PMID:25838825

The mitochondrion interfering compound NPC-26 exerts potent anti-pancreatic cancer cell activity in vitro and in vivo.

PubMed

Dong, Yang-Yang; Zhuang, Yi-Huang; Cai, Wen-Jie; Liu, Yan; Zou, Wen-Bing

2016-11-01

The development of novel anti-pancreatic cancer agents is extremely important. Here, we investigated the anti-pancreatic cancer activity by NPC-26, a novel mitochondrion interfering compound. We showed that NPC-26 was anti-proliferative and cytotoxic to human pancreatic cancer cells, possibly via inducing caspase-9-dependent cell apoptosis. Pharmacological inhibition or shRNA-mediated silence of caspase-9 attenuated NPC-26-induced pancreatic cancer cell death and apoptosis. Further, NPC-26 treatment led to mitochondrial permeability transition pore (mPTP) opening in the cancer cells, which was evidenced by mitochondrial depolarization, ANT-1(adenine nucleotide translocator-1)-Cyp-D (cyclophilin-D) association and oxidative phosphorylation disturbance. mPTP blockers (cyclosporin and sanglifehrin A) or shRNA-mediated knockdown of key mPTP components (Cyp-D and ANT-1) dramatically attenuated NPC-26-induced pancreatic cancer cell apoptosis. Importantly, we showed that NPC-26, at a low concentration, potentiated gemcitabine-induced mPTP opening and subsequent pancreatic cancer cell apoptosis. In vivo, NPC-26 intraperitoneal injection significantly suppressed the growth of PANC-1 xenograft tumors in nude mice. Meanwhile, NPC-26 sensitized gemcitabine-mediated anti-pancreatic cancer activity in vivo. In summary, the results of this study suggest that NPC-26, alone or together with gemcitabine, potently inhibits pancreatic cancer cells possibly via disrupting mitochondrion.

FDA Approves Irinotecan Liposome to Treat Pancreatic Cancer

Cancer.gov

Patients with metastatic pancreatic cancer that has progressed after receiving gemcitabine-based chemotherapy now have a new treatment option: irinotecan liposome in combination with fluorouracil and leucovorin.

Current Management of Gallbladder Carcinoma

PubMed Central

Hong, Theodore S.; Hezel, Aram F.; Kooby, David A.

2010-01-01

Gallbladder cancer (GBC) represents the most common and aggressive type among the biliary tree cancers (BTCs). Complete surgical resection offers the only chance for cure; however, only 10% of patients with GBC present with early-stage disease and are considered surgical candidates. Among those patients who do undergo “curative” resection, recurrence rates are high. There are no established adjuvant treatments in this setting. Patients with unresectable or metastatic GBC have a poor prognosis. There has been a paucity of randomized phase III data in this field. A recent report demonstrated longer overall survival with gemcitabine in combination with cisplatin than with gemcitabine alone in patients with advanced or metastatic BTCs. Molecularly targeted agents are under development. In this review, we attempt to discuss the current status and key issues involved in the management of GBC. PMID:20147507

Bacterial Unculturability and the Formation of Intercellular Metabolic Networks.

PubMed

Pande, Samay; Kost, Christian

2017-05-01

The majority of known bacterial species cannot be cultivated under laboratory conditions. Here we argue that the adaptive emergence of obligate metabolic interactions in natural bacterial communities can explain this pattern. Bacteria commonly release metabolites into the external environment. Accumulating pools of extracellular metabolites create an ecological niche that benefits auxotrophic mutants, which have lost the ability to autonomously produce the corresponding metabolites. In addition to a diffusion-based metabolite transfer, auxotrophic cells can use contact-dependent means to obtain nutrients from other co-occurring cells. Spatial colocalisation and a continuous coevolution further increase the nutritional dependency and optimise fluxes through combined metabolic networks. Thus, bacteria likely function as networks of interacting cells that reciprocally exchange nutrients and biochemical functions rather than as physiologically autonomous units. Copyright © 2017 Elsevier Ltd. All rights reserved.

In vitro investigation of intestinal transport mechanism of silicon, supplied as orthosilicic acid-vanillin complex.

PubMed

Sergent, Thérèse; Croizet, Karine; Schneider, Yves-Jacques

2017-02-01

Silicon (Si) is one of the most abundant trace elements in the body. Although pharmacokinetics data described its absorption from the diet and its body excretion, the mechanisms involved in the uptake and transport of Si across the gut wall have not been established. Caco-2 cells were used as a well-accepted in vitro model of the human intestinal epithelium to investigate the transport, across the intestinal barrier in both the absorption and excretion directions, of Si supplied as orthosilicic acid stabilized by vanillin complex (OSA-VC). The transport of this species was found proportional to the initial concentration and to the duration of incubation, with absorption and excretion mean rates similar to those of Lucifer yellow, a marker of paracellular diffusion, and increasing in the presence of EGTA, a chelator of divalents cations including calcium. A cellular accumulation of Si, polarized from the apical side of cells, was furthermore detected. These results provide evidence that Si, ingested as a food supplement containing OSA-VC, crosses the intestinal mucosa by passive diffusion via the paracellular pathway through the intercellular tight junctions and accumulates intracellularly, probably by an uptake mechanism of facilitated diffusion. This study can help to further understand the kinetic of absorption of Si. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Probabilistic modeling of percutaneous absorption for risk-based exposure assessments and transdermal drug delivery.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ho, Clifford Kuofei

Chemical transport through human skin can play a significant role in human exposure to toxic chemicals in the workplace, as well as to chemical/biological warfare agents in the battlefield. The viability of transdermal drug delivery also relies on chemical transport processes through the skin. Models of percutaneous absorption are needed for risk-based exposure assessments and drug-delivery analyses, but previous mechanistic models have been largely deterministic. A probabilistic, transient, three-phase model of percutaneous absorption of chemicals has been developed to assess the relative importance of uncertain parameters and processes that may be important to risk-based assessments. Penetration routes through the skinmore » that were modeled include the following: (1) intercellular diffusion through the multiphase stratum corneum; (2) aqueous-phase diffusion through sweat ducts; and (3) oil-phase diffusion through hair follicles. Uncertainty distributions were developed for the model parameters, and a Monte Carlo analysis was performed to simulate probability distributions of mass fluxes through each of the routes. Sensitivity analyses using stepwise linear regression were also performed to identify model parameters that were most important to the simulated mass fluxes at different times. This probabilistic analysis of percutaneous absorption (PAPA) method has been developed to improve risk-based exposure assessments and transdermal drug-delivery analyses, where parameters and processes can be highly uncertain.« less

A phase 1/1B trial of ADI-PEG 20 plus nab-paclitaxel and gemcitabine in patients with advanced pancreatic adenocarcinoma.

PubMed

Lowery, Maeve A; Yu, Kenneth H; Kelsen, David Paul; Harding, James J; Bomalaski, John S; Glassman, Danielle C; Covington, Christina M; Brenner, Robin; Hollywood, Ellen; Barba, Adalberto; Johnston, Amanda; Liu, Kay Chia-Wei; Feng, Xiaoxing; Capanu, Marinela; Abou-Alfa, Ghassan K; O'Reilly, Eileen M

2017-12-01

ADI-PEG 20 is a pegylated form of the arginine-depleting enzyme arginine deiminase. Normal cells synthesize arginine with the enzyme argininosuccinate synthetase (ASS1); ADI-PEG 20 selectively targets malignant cells, which lack ASS1. A single-arm, nonrandomized, open-label, phase 1/1B, standard 3 + 3 dose escalation with an expansion cohort of 9 patients at the recommended phase 2 dose (RP2D) was conducted. Patients who had metastatic pancreatic cancer, up to 1 line of prior treatment (the dose-escalation cohort) or no prior treatment (the expansion cohort), and an Eastern Cooperative Oncology Group performance status of 0 to 1 were included. Patients received both gemcitabine (1000 mg/m 2 ) and nab-paclitaxel (125 mg/m 2 ) for 3 of 4 weeks and intramuscular ADI-PEG 20 at 18 mg/m 2 weekly (cohort 1) or at 36 mg/m 2 weekly (cohort 2 and the expansion cohort).The primary endpoint was to determine the maximum tolerated dose and RP2D of ADI-PEG 20 in combination with nab-paclitaxel and gemcitabine. Eighteen patients were enrolled. No dose-limiting toxicities (DLTs) were observed in cohort 1; cohort 2 was expanded to 6 patients because of 1 DLT occurrence (a grade 3 elevation in bilirubin, aspartate aminotransferase, and alanine aminotransferase). The most frequent adverse events (AEs) of any grade were neutropenia, thrombocytopenia, leukopenia, anemia, peripheral neuropathy, and fatigue; all 18 patients experienced grade 3/4 AEs. The most frequent grade 3/4 toxicities, regardless of the relation with any drugs, included neutropenia (12 patients or 67%), leukopenia (10 patients or 56%), anemia (8 patients or 44%), and lymphopenia (6 patients or 33%). The RP2D for ADI-PEG 20 was 36 mg/m 2 weekly in combination with standard-dose gemcitabine and nab-paclitaxel. The overall response rate among patients treated at the RP2D in the first-line setting was 45.5% (5 of 11).The median progression-free survival time for these patients treated at the RP2D was 6.1 months (95% confidence interval, 5.3-11.2 months), and the median overall survival time was 11.3 months (95% confidence interval, 6.7 months to not reached). ADI-PEG 20 was well tolerated in combination with gemcitabine and nab-paclitaxel. Activity was observed in previously treated and untreated patients with advanced pancreatic cancer and in patients with ASS1-deficient and -proficient tumors. Cancer 2017;123:4556-4565. © 2017 American Cancer Society. © 2017 American Cancer Society.

Depicting changes in tumor biology in response to cetuximab mono- or combination therapy by apoptosis and proliferation imaging using 18F-ICMT-11 and 3'-Deoxy-3'-[18F]Fluorothymidine (18F-FLT) PET.

PubMed

Heinzmann, Kathrin; Nguyen, Quang-De; Honess, Davina Jean; Smith, Donna-Michelle; Stribbling, Stephen; Brickute, Diana; Barnes, Christopher; Griffiths, John Richard; Aboagye, Eric Ofori

2018-05-24

Imaging biomarkers must demonstrate their value in monitoring treatment. Two PET tracers, the caspase-3/7-specific isatin-5-sulfonamide 18 F-ICMT-11 and 3'-Deoxy-3'-[ 18 F]Fluorothymidine ( 18 F-FLT), were employed to detect early treatment-induced changes in tumor biology and whether any changes indicate response to cetuximab, administered as mono- or combination therapy with gemcitabine. Methods: Effects of single or repeated doses of the anti-Epidermal Growth Factor Receptor (EGFR) antibody cetuximab (10mg/kg on day 1 only or day 1 and 2) and/or a single dose of gemcitabine (125mg/kg; day 2) were investigated in mice bearing cetuximab-sensitive H1975 tumors (non-small cell lung cancer) by 18 F-ICMT-11 or 18 F-FLT-PET (day 3). Imaging was also performed in mice bearing cetuximab-insensitive HCT116 tumors (colorectal cancer) after two doses of cetuximab (day 1 and 2). For imaging/histology comparison, tumors were evaluated for proliferation (Ki67; thymidine kinase 1, TK1), cell death (cleaved caspase-3, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL)) and target engagement (EGFR expression) by immunohistochemistry, immunofluorescence and immunoblot, respectively. Tumor and plasma were analysed for thymidine and gemcitabine metabolites by liquid chromatography-mass spectrometry. Results: Retention of both tracers was sensitive to cetuximab in H1975 tumors. 18 F-ICMT-11 uptake and ex vivo cleaved caspase-3 staining notably increased in tumors treated with repeated doses of cetuximab- (75%) and combination-treatment (46%). While one dose of cetuximab was insufficient to induce apoptosis it did affect proliferation. Significant reduction in tumor 18 F-FLT uptake (44 to 50%; P < 0.001) induced by cetuximab mono- and combination-therapy were paralleled with a clear decrease in proliferation (%Ki67 decrease: 72 to 95%; P < 0.0001) and followed by marked tumor growth delay. TK1 expression and tumor thymidine concentrations were profoundly reduced. Neither imaging tracer depicted the gemcitabine-induced tumor changes. However, cleaved caspase-3 and Ki67 staining were not significantly different while TK1 expression and thymidine concentrations increased after gemcitabine-treatment. No cetuximab-induced modulation of the imaging tracers or other response markers was detected in the insensitive model HCT116. Conclusion: 18 F-ICMT-11 and 18 F-FLT are valuable tools to assess cetuximab-sensitivity depicting distinct and time-variant aspects of treatment response. Copyright © 2018 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Porcine Reproductive and Respiratory Syndrome Virus Utilizes Nanotubes for Intercellular Spread

PubMed Central

Guo, Rui; Katz, Benjamin B.; Tomich, John M.; Gallagher, Tom

2016-01-01

ABSTRACT Intercellular nanotube connections have been identified as an alternative pathway for cellular spreading of certain viruses. In cells infected with porcine reproductive and respiratory syndrome virus (PRRSV), nanotubes were observed connecting two distant cells with contiguous membranes, with the core infectious viral machinery (viral RNA, certain replicases, and certain structural proteins) present in/on the intercellular nanotubes. Live-cell movies tracked the intercellular transport of a recombinant PRRSV that expressed green fluorescent protein (GFP)-tagged nsp2. In MARC-145 cells expressing PRRSV receptors, GFP-nsp2 moved from one cell to another through nanotubes in the presence of virus-neutralizing antibodies. Intercellular transport of viral proteins did not require the PRRSV receptor as it was observed in receptor-negative HEK-293T cells after transfection with an infectious clone of GFP-PRRSV. In addition, GFP-nsp2 was detected in HEK-293T cells cocultured with recombinant PRRSV-infected MARC-145 cells. The intercellular nanotubes contained filamentous actin (F-actin) with myosin-associated motor proteins. The F-actin and myosin IIA were identified as coprecipitates with PRRSV nsp1β, nsp2, nsp2TF, nsp4, nsp7-nsp8, GP5, and N proteins. Drugs inhibiting actin polymerization or myosin IIA activation prevented nanotube formation and viral clusters in virus-infected cells. These data lead us to propose that PRRSV utilizes the host cell cytoskeletal machinery inside nanotubes for efficient cell-to-cell spread. This form of virus transport represents an alternative pathway for virus spread, which is resistant to the host humoral immune response. IMPORTANCE Extracellular virus particles transmit infection between organisms, but within infected hosts intercellular infection can be spread by additional mechanisms. In this study, we describe an alternative pathway for intercellular transmission of PRRSV in which the virus uses nanotube connections to transport infectious viral RNA, certain replicases, and certain structural proteins to neighboring cells. This process involves interaction of viral proteins with cytoskeletal proteins that form the nanotube connections. Intercellular viral spread through nanotubes allows the virus to escape the neutralizing antibody response and may contribute to the pathogenesis of viral infections. The development of strategies that interfere with this process could be critical in preventing the spread of viral infection. PMID:26984724

Connexin Type and Fluorescent Protein Fusion Tag Determine Structural Stability of Gap Junction Plaques.

PubMed

Stout, Randy F; Snapp, Erik Lee; Spray, David C

2015-09-25

Gap junctions (GJs) are made up of plaques of laterally clustered intercellular channels and the membranes in which the channels are embedded. Arrangement of channels within a plaque determines subcellular distribution of connexin binding partners and sites of intercellular signaling. Here, we report the discovery that some connexin types form plaque structures with strikingly different degrees of fluidity in the arrangement of the GJ channel subcomponents of the GJ plaque. We uncovered this property of GJs by applying fluorescence recovery after photobleaching to GJs formed from connexins fused with fluorescent protein tags. We found that connexin 26 (Cx26) and Cx30 GJs readily diffuse within the plaque structures, whereas Cx43 GJs remain persistently immobile for more than 2 min after bleaching. The cytoplasmic C terminus of Cx43 was required for stability of Cx43 plaque arrangement. We provide evidence that these qualitative differences in GJ arrangement stability reflect endogenous characteristics, with the caveat that the sizes of the GJs examined were necessarily large for these measurements. We also uncovered an unrecognized effect of non-monomerized fluorescent protein on the dynamically arranged GJs and the organization of plaques composed of multiple connexin types. Together, these findings redefine our understanding of the GJ plaque structure and should be considered in future studies using fluorescent protein tags to probe dynamics of highly ordered protein complexes. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Air volume measurement of 'Braeburn' apple fruit.

PubMed

Drazeta, Lazar; Lang, Alexander; Hall, Alistair J; Volz, Richard K; Jameson, Paula E

2004-05-01

The radial disposition of air in the flesh of fruit of Malus domestica Borkh., cv 'Braeburn' was investigated using a gravimetric technique based on Archimedes' principle. Intercellular air volume was measured by weighing a small tissue sample under water before and after vacuum infiltration to remove the air. In a separate procedure, the volume of the same sample was measured by recording the buoyant upthrust experienced by it when fully immersed in water. The method underestimates tissue air volume due to a slight invasion of the intercellular air spaces around the edges of the sample when it is immersed in water. To correct for this error, an adjustment factor was made based upon an analysis of a series of measurements of air volume in samples of different dimensions. In 'Braeburn' there is a gradient of declining air content from just beneath the skin to the centre of the fruit with a sharp discontinuity at the core line. Cell shape and cell packing were observed in the surface layers of freshly excised and stained flesh samples using a dissecting microscope coupled to a video camera and a PC running proprietary software. Tissue organization changed with distance below the skin. It is speculated that reduced internal gas movement, due to the tightly packed tissue of 'Braeburn' and to the potential diffusion barrier at the core line between the cortex and the pith, may increase susceptibility of the flesh to disorders associated with tissue browning and breakdown.

Quantification of gap junction selectivity.

PubMed

Ek-Vitorín, Jose F; Burt, Janis M

2005-12-01

Gap junctions, which are essential for functional coordination and homeostasis within tissues, permit the direct intercellular exchange of small molecules. The abundance and diversity of this exchange depends on the number and selectivity of the comprising channels and on the transjunctional gradient for and chemical character of the permeant molecules. Limited knowledge of functionally significant permeants and poor detectability of those few that are known have made it difficult to define channel selectivity. Presented herein is a multifaceted approach to the quantification of gap junction selectivity that includes determination of the rate constant for intercellular diffusion of a fluorescent probe (k2-DYE) and junctional conductance (gj) for each junction studied, such that the selective permeability (k2-DYE/gj) for dyes with differing chemical characteristics or junctions with differing connexin (Cx) compositions (or treatment conditions) can be compared. In addition, selective permeability can be correlated using single-channel conductance when this parameter is also measured. Our measurement strategy is capable of detecting 1) rate constants and selective permeabilities that differ across three orders of magnitude and 2) acute changes in that rate constant. Using this strategy, we have shown that 1) the selective permeability of Cx43 junctions to a small cationic dye varied across two orders of magnitude, consistent with the hypothesis that the various channel configurations adopted by Cx43 display different selective permeabilities; and 2) the selective permeability of Cx37 vs. Cx43 junctions was consistently and significantly lower.

Brain Extracellular Space: The Final Frontier of Neuroscience.

PubMed

Nicholson, Charles; Hrabětová, Sabina

2017-11-21

Brain extracellular space is the narrow microenvironment that surrounds every cell of the central nervous system. It contains a solution that closely resembles cerebrospinal fluid with the addition of extracellular matrix molecules. The space provides a reservoir for ions essential to the electrical activity of neurons and forms an intercellular chemical communication channel. Attempts to reveal the size and structure of the extracellular space using electron microscopy have had limited success; however, a biophysical approach based on diffusion of selected probe molecules has proved useful. A point-source paradigm, realized in the real-time iontophoresis method using tetramethylammonium, as well as earlier radiotracer methods, have shown that the extracellular space occupies ∼20% of brain tissue and small molecules have an effective diffusion coefficient that is two-fifths that in a free solution. Monte Carlo modeling indicates that geometrical constraints, including dead-space microdomains, contribute to the hindrance to diffusion. Imaging the spread of macromolecules shows them increasingly hindered as a function of size and suggests that the gaps between cells are predominantly ∼40 nm with wider local expansions that may represent dead-spaces. Diffusion measurements also characterize interactions of ions and proteins with the chondroitin and heparan sulfate components of the extracellular matrix; however, the many roles of the matrix are only starting to become apparent. The existence and magnitude of bulk flow and the so-called glymphatic system are topics of current interest and controversy. The extracellular space is an exciting area for research that will be propelled by emerging technologies. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Weak Ergodicity Breaking of Receptor Motion in Living Cells Stemming from Random Diffusivity

NASA Astrophysics Data System (ADS)

Manzo, Carlo; Torreno-Pina, Juan A.; Massignan, Pietro; Lapeyre, Gerald J.; Lewenstein, Maciej; Garcia Parajo, Maria F.

2015-01-01

Molecular transport in living systems regulates numerous processes underlying biological function. Although many cellular components exhibit anomalous diffusion, only recently has the subdiffusive motion been associated with nonergodic behavior. These findings have stimulated new questions for their implications in statistical mechanics and cell biology. Is nonergodicity a common strategy shared by living systems? Which physical mechanisms generate it? What are its implications for biological function? Here, we use single-particle tracking to demonstrate that the motion of dendritic cell-specific intercellular adhesion molecule 3-grabbing nonintegrin (DC-SIGN), a receptor with unique pathogen-recognition capabilities, reveals nonergodic subdiffusion on living-cell membranes In contrast to previous studies, this behavior is incompatible with transient immobilization, and, therefore, it cannot be interpreted according to continuous-time random-walk theory. We show that the receptor undergoes changes of diffusivity, consistent with the current view of the cell membrane as a highly dynamic and diverse environment. Simulations based on a model of an ordinary random walk in complex media quantitatively reproduce all our observations, pointing toward diffusion heterogeneity as the cause of DC-SIGN behavior. By studying different receptor mutants, we further correlate receptor motion to its molecular structure, thus establishing a strong link between nonergodicity and biological function. These results underscore the role of disorder in cell membranes and its connection with function regulation. Because of its generality, our approach offers a framework to interpret anomalous transport in other complex media where dynamic heterogeneity might play a major role, such as those found, e.g., in soft condensed matter, geology, and ecology.

Cell remodeling and subtilase gene expression in the actinorhizal plant Discaria trinervis highlight host orchestration of intercellular Frankia colonization.

PubMed

Fournier, Joëlle; Imanishi, Leandro; Chabaud, Mireille; Abdou-Pavy, Iltaf; Genre, Andrea; Brichet, Lukas; Lascano, Hernán Ramiro; Muñoz, Nacira; Vayssières, Alice; Pirolles, Elodie; Brottier, Laurent; Gherbi, Hassen; Hocher, Valérie; Svistoonoff, Sergio; Barker, David G; Wall, Luis G

2018-05-23

Nitrogen-fixing filamentous Frankia colonize the root tissues of its actinorhizal host Discaria trinervis via an exclusively intercellular pathway. Here we present studies aimed at uncovering mechanisms associated with this little-researched mode of root entry, and in particular the extent to which the host plant is an active partner during this process. Detailed characterization of the expression patterns of infection-associated actinorhizal host genes has provided valuable tools to identify intercellular infection sites, thus allowing in vivo confocal microscopic studies of the early stages of Frankia colonization. The subtilisin-like serine protease gene Dt12, as well as its Casuarina glauca homolog Cg12, are specifically expressed at sites of Frankia intercellular colonization of D. trinervis outer root tissues. This is accompanied by nucleo-cytoplasmic reorganization in the adjacent host cells and major remodeling of the intercellular apoplastic compartment. These findings lead us to propose that the actinorhizal host plays a major role in modifying both the size and composition of the intercellular apoplast in order to accommodate the filamentous microsymbiont. The implications of these findings are discussed in the light of the analogies that can be made with the orchestrating role of host legumes during intracellular root hair colonization by nitrogen-fixing rhizobia. © 2018 The Authors New Phytologist © 2018 New Phytologist Trust.

European Mistletoe

MedlinePlus

... Audio) NCCIH Clinical Digest A monthly newsletter with evidence-based information on complementary and integrative practices and a ... and gemcitabine in patients with advanced solid tumors. Evidence-Based Complementary and Alternative Medicine. 2013;2013:964592. National ...

Neoadjuvant Chemotherapy Followed by Radiation Therapy and Gemcitabine/Sorafenib/Vorinostat in Pancreatic Cancer

ClinicalTrials.gov

2017-11-29

Pancreatic Adenocarcinoma; Stage IA Pancreatic Cancer; Stage IB Pancreatic Cancer; Stage IIA Pancreatic Cancer; Stage IIB Pancreatic Cancer; Stage III Pancreatic Cancer; Recurrent Pancreatic Carcinoma

Phase II Study of Gemcitabine, Carboplatin, and Iniparib As Neoadjuvant Therapy for Triple-Negative and BRCA1/2 Mutation–Associated Breast Cancer With Assessment of a Tumor-Based Measure of Genomic Instability: PrECOG 0105

PubMed Central

Telli, Melinda L.; Jensen, Kristin C.; Vinayak, Shaveta; Kurian, Allison W.; Lipson, Jafi A.; Flaherty, Patrick J.; Timms, Kirsten; Abkevich, Victor; Schackmann, Elizabeth A.; Wapnir, Irene L.; Carlson, Robert W.; Chang, Pei-Jen; Sparano, Joseph A.; Head, Bobbie; Goldstein, Lori J.; Haley, Barbara; Dakhil, Shaker R.; Reid, Julia E.; Hartman, Anne-Renee; Manola, Judith; Ford, James M.

2015-01-01

Purpose This study was designed to assess efficacy, safety, and predictors of response to iniparib in combination with gemcitabine and carboplatin in early-stage triple-negative and BRCA1/2 mutation–associated breast cancer. Patients and Methods This single-arm phase II study enrolled patients with stage I to IIIA (T ≥ 1 cm) estrogen receptor–negative (≤ 5%), progesterone receptor–negative (≤ 5%), and human epidermal growth factor receptor 2–negative or BRCA1/2 mutation–associated breast cancer. Neoadjuvant gemcitabine (1,000 mg/m2 intravenously [IV] on days 1 and 8), carboplatin (area under curve of 2 IV on days 1 and 8), and iniparib (5.6 mg/kg IV on days 1, 4, 8, and 11) were administered every 21 days for four cycles, until the protocol was amended to six cycles. The primary end point was pathologic complete response (no invasive carcinoma in breast or axilla). All patients underwent comprehensive BRCA1/2 genotyping, and homologous recombination deficiency was assessed by loss of heterozygosity (HRD-LOH) in pretreatment core breast biopsies. Results Among 80 patients, median age was 48 years; 19 patients (24%) had germline BRCA1 or BRCA2 mutations; clinical stage was I (13%), IIA (36%), IIB (36%), and IIIA (15%). Overall pathologic complete response rate in the intent-to-treat population (n = 80) was 36% (90% CI, 27 to 46). Mean HRD-LOH scores were higher in responders compared with nonresponders (P = .02) and remained significant when BRCA1/2 germline mutations carriers were excluded (P = .021). Conclusion Preoperative combination of gemcitabine, carboplatin, and iniparib is active in the treatment of early-stage triple-negative and BRCA1/2 mutation–associated breast cancer. The HRD-LOH assay was able to identify patients with sporadic triple-negative breast cancer lacking a BRCA1/2 mutation, but with an elevated HRD-LOH score, who achieved a favorable pathologic response. Confirmatory controlled trials are warranted. PMID:25847929

Dose-Volume Analysis of Predictors for Gastrointestinal Toxicity After Concurrent Full-Dose Gemcitabine and Radiotherapy for Locally Advanced Pancreatic Adenocarcinoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang Jiayi; Robertson, John M., E-mail: jrobertson@beaumont.edu; Ye Hong

2012-07-15

Purpose: To identify dosimetric predictors for the development of gastrointestinal (GI) toxicity in patients with locally advanced pancreatic adenocarcinoma (LAPC) treated with concurrent full-dose gemcitabine and radiotherapy (GemRT). Methods and Materials: From June 2002 to June 2009, 46 LAPC patients treated with definitive GemRT were retrospectively analyzed. The stomach and duodenum were retrospectively contoured separately to determine their dose-volume histogram (DVH) parameters. GI toxicity was defined as Grade 3 or higher GI toxicity. The follow-up time was calculated from the start of RT to the date of death or last contact. Univariate analysis (UVA) and multivariate analysis (MVA) using Kaplan-Meiermore » and Cox regression models were performed to identify risk factors associated with GI toxicity. The receiver operating characteristic curve and the area under the receiver operating characteristic curve (AUC) were used to determine the best DVH parameter to predict for GI toxicity. Results: Of the patients, 28 (61%) received concurrent gemcitabine alone, and 18 (39%) had concurrent gemcitabine with daily erlotinib. On UVA, only the V{sub 20Gy} to V{sub 35Gy} of duodenum were significantly associated with GI toxicity (all p {<=} 0.05). On MVA, the V{sub 25Gy} of duodenum and the use of erlotinib were independent risk factors for GI toxicity (p = 0.006 and 0.02, respectively). For the entire cohort, the V{sub 25Gy} of duodenum is the best predictor for GI toxicity (AUC = 0.717), and the 12-month GI toxicity rate was 8% vs. 48% for V{sub 25Gy} {<=} 45% and V{sub 25Gy} > 45%, respectively (p = 0.03). However, excluding the erlotinib group, the V{sub 35Gy} is the best predictor (AUC = 0.725), and the 12-month GI toxicity rate was 0% vs. 41% for V{sub 35Gy} {<=} 20% and V{sub 35Gy} > 20%, respectively (p = 0.04). Conclusions: DVH parameters of duodenum may predict Grade 3 GI toxicity after GemRT for LAPC. Concurrent use of erlotinib during GemRT may increase GI toxicity.« less

Prospective randomized double-blind multicentre phase II study comparing gemcitabine and cisplatin plus sorafenib chemotherapy with gemcitabine and cisplatin plus placebo in locally advanced and/or metastasized urothelial cancer: SUSE (AUO-AB 31/05).

PubMed

Krege, Susanne; Rexer, Heidrun; vom Dorp, Frank; de Geeter, Patrick; Klotz, Theodor; Retz, Margitte; Heidenreich, Axel; Kühn, Michael; Kamradt, Joern; Feyerabend, Susan; Wülfing, Christian; Zastrow, Stefan; Albers, Peter; Hakenberg, Oliver; Roigas, Jan; Fenner, Martin; Heinzer, Hans; Schrader, Mark

2014-03-01

To evaluate the efficacy and safety of gemcitabine and cisplatin in combination with sorafenib, a tyrosine-kinase inhibitor, compared with chemotherapy alone as first-line treatment in advanced urothelial cancer. The study was a randomized phase II trial. Its primary aim was to show an improvement in progression-free survival (PFS) of 4.5 months by adding sorafenib to conventional chemotherapy. Secondary objectives were objective response rate (ORR), overall survival (OS) and toxicity. The patients included in the trial had histologically confirmed locally advanced and/or metastatic urothelial cancer of the bladder or upper urinary tract. Chemotherapy with gemcitabine (1250 mg/qm on days 1 and 8) and cisplatin (70 mg/qm on day 1) repeated every 21 days, was administered to all patients in a double-blind randomization of additional sorafenib (400 mg twice daily) vs placebo (two tablets twice daily) on days 3-21. Treatment continued until progression or unacceptable toxicity, the maximum number of cycles was limited to eight. The response assessment was repeated after every two cycles. Between October 2006 and October 2010, 98 of 132 planned patients were recruited. Nine patients were ineligible. The final analysis included 40 patients in the sorafenib and 49 patients in the placebo arm. There were no significant differences between the two arms concerning ORR (sorafenib: complete response [CR] 12.5%, partial response [PR] 40%; placebo: CR 12%, PR 35%), median PFS (sorafenib: 6.3 months, placebo: 6.1 months) or OS (sorafenib: 11.3 months, placebo: 10.6 months). Toxicity was moderately higher in the sorafenib arm. Diarrrhoea occurred significantly more often in the sorafenib arm and hand-foot syndrome occurred only in the sorafenib arm. The study was closed prematurely because of slow recruitment. Although the addition of sorafenib to standard chemotherapy showed acceptable toxicity, the trial failed to show a 4.5 months improvement in PFS. © 2013 The Authors. BJU International © 2013 BJU International.

Antitumor activity of erlotinib (OSI-774, Tarceva) alone or in combination in human non-small cell lung cancer tumor xenograft models.

PubMed

Higgins, Brian; Kolinsky, Kenneth; Smith, Melissa; Beck, Gordon; Rashed, Mohammad; Adames, Violeta; Linn, Michael; Wheeldon, Eric; Gand, Laurent; Birnboeck, Herbert; Hoffmann, Gerhard

2004-06-01

Our objective was the preclinical assessment of the pharmacokinetics, monotherapy and combined antitumor activity of the epidermal growth factor receptor (HER1/EGFR) tyrosine kinase inhibitor erlotinib in athymic nude mice bearing non-small cell lung cancer (NSCLC) xenograft models. Immunohistochemistry determined the HER1/EGFR status of the NSCLC tumor models. Pharmacokinetic studies assessed plasma drug concentrations of erlotinib in tumor- and non-tumor-bearing athymic nude mice. These were followed by maximum tolerated dose (MTD) studies for erlotinib and each chemotherapy. Erlotinib was then assessed alone and in combination with these chemotherapies in the NSCLC xenograft models. Complete necropsies were performed on most of the animals in each study to further assess antitumor or toxic effects. Erlotinib monotherapy dose-dependently inhibited tumor growth in the H460a tumor model, correlating with circulating levels of drug. There was antitumor activity at the MTD with each agent tested in both the H460a and A549 tumor models (erlotinib 100 mg/kg: 71 and 93% tumor growth inhibition; gemcitabine 120 mg/kg: 93 and 75% tumor growth inhibition; cisplatin 6 mg/kg: 81 and 88% tumor growth inhibition). When each compound was given at a fraction of the MTD, tumor growth inhibition was suboptimal. Combinations of gemcitabine or cisplatin with erlotinib were assessed at 25% of the MTD to determine efficacy. In both NSCLC models, doses of gemcitabine (30 mg/kg) or cisplatin (1.5 mg/kg) with erlotinib (25 mg/kg) at 25% of the MTD were well tolerated. For the slow growing A549 tumor, there was significant tumor growth inhibition in the gemcitabine/erlotinib and cisplatin/erlotinib combinations (above 100 and 98%, respectively), with partial regressions. For the faster growing H460a tumor, there was significant but less remarkable tumor growth inhibition in these same combinations (86 and 53% respectively). These results show that in NSCLC xenograft tumors with similar levels of EGFR expression, the antitumor activity of erlotinib is robust both as monotherapy and in combination with chemotherapies.

Salvage chemotherapy of gemcitabine, dexamethasone, and cisplatin (GDP) for patients with relapsed or refractory peripheral T-cell lymphomas: a consortium for improving survival of lymphoma (CISL) trial.

PubMed

Park, Byeong-Bae; Kim, Won Seog; Suh, Cheolwon; Shin, Dong-Yeop; Kim, Jeong-A; Kim, Hoon-Gu; Lee, Won Sik

2015-11-01

There is no standard salvage chemotherapy for relapsed or refractory peripheral T-cell lymphomas (PTCLs). Gemcitabine combined with cisplatin has been known as an effective regimen for lymphoma treatment in the salvage setting. We investigated the efficacy and toxicity of gemcitabine, dexamethasone, and cisplatin (GDP) for relapsed or refractory PTCLs in search of a more effective and less toxic therapy. Patients with relapsed or refractory PTCLs with more than one previous regimen were eligible. Treatment consisted of gemcitabine 1000 mg/m(2) intravenously (i.v.) on days 1 and 8, dexamethasone 40 mg orally on days 1-4, and cisplatin 70 mg/m(2) i.v. on day 1, and then every 21 days. Patients could proceed to autologous stem cell transplantation (ASCT) after four cycles of GDP or receive up to six treatment cycles. Twenty-five eligible patients were evaluated for toxicity and response. The diagnoses of participants included 14 cases of PTCL-not otherwise specified (NOS) (56 %) and four cases of angioimmunoblastic T-cell lymphoma (16 %) among others. The median age of the patients was 59 years (range 20-75 years). After treatments with GDP, which delivered a median of four GDP cycles, there were 12 patients with complete responses (CR; 48 %) and six with partial responses (PR; 24 %). The overall response rate (RR) was 72 %. Four patients preceded to ASCT, and three patients finally achieved CR. The median progression free survival was 9.3 months (95 % confidence interval (CI); 4.1-14.6) with a median follow-up duration of 27.1 months. In a total of 86 cycles of GDP, grade 3 or 4 neutropenia and thrombocytopenia occurred in 16.3 and 12.8 % of cycles, respectively. Three patients (3.3 %) experienced febrile neutropenia. GDP is a highly effective and optimal salvage regimen for relapsed or refractory PTCLs and can be administered with acceptable toxicity.

Extracellular ultrathin fibers sensitive to intracellular reactive oxygen species: Formation of intercellular membrane bridges

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jung, Se-Hui; Park, Jin-Young; Joo, Jung-Hoon

2011-07-15

Membrane bridges are key cellular structures involved in intercellular communication; however, dynamics for their formation are not well understood. We demonstrated the formation and regulation of novel extracellular ultrathin fibers in NIH3T3 cells using confocal and atomic force microscopy. At adjacent regions of neighboring cells, phorbol 12-myristate 13-acetate (PMA) and glucose oxidase induced ultrathin fiber formation, which was prevented by Trolox, a reactive oxygen species (ROS) scavenger. The height of ROS-sensitive ultrathin fibers ranged from 2 to 4 nm. PMA-induced formation of ultrathin fibers was inhibited by cytochalasin D, but not by Taxol or colchicine, indicating that ultrathin fibers mainlymore » comprise microfilaments. PMA-induced ultrathin fibers underwent dynamic structural changes, resulting in formation of intercellular membrane bridges. Thus, these fibers are formed by a mechanism(s) involving ROS and involved in formation of intercellular membrane bridges. Furthermore, ultrastructural imaging of ultrathin fibers may contribute to understanding the diverse mechanisms of cell-to-cell communication and the intercellular transfer of biomolecules, including proteins and cell organelles.« less

Gemcitabine and Bendamustine in Patients With Relapsed or Refractory Hodgkin's Lymphoma

ClinicalTrials.gov

2018-04-02

Adult Lymphocyte Depletion Hodgkin Lymphoma; Adult Lymphocyte Predominant Hodgkin Lymphoma; Adult Mixed Cellularity Hodgkin Lymphoma; Adult Nodular Lymphocyte Predominant Hodgkin Lymphoma; Adult Nodular Sclerosis Hodgkin Lymphoma; Recurrent Adult Hodgkin Lymphoma

CD40 Agonists Alter Tumor Stroma and Show Efficacy Against Pancreatic Carcinoma in Mice and Humans

PubMed Central

Beatty, Gregory L.; Chiorean, Elena G.; Fishman, Matthew P.; Saboury, Babak; Teitelbaum, Ursina R.; Sun, Weijing; Huhn, Richard D.; Song, Wenru; Li, Dongguang; Sharp, Leslie L.; Torigian, Drew A.; O’Dwyer, Peter J.; Vonderheide, Robert H.

2012-01-01

Immunosuppressive tumor microenvironments can restrain antitumor immunity, particularly in pancreatic ductal adenocarcinoma (PDA). Because CD40 activation can reverse immune suppression and drive antitumor T cell responses, we tested the combination of an agonist CD40 antibody with gemcitabine chemotherapy in a small cohort of patients with surgically incurable PDA and observed tumor regressions in some patients. We reproduced this treatment effect in a genetically engineered mouse model of PDA and found unexpectedly that tumor regression required macrophages but not T cells or gemcitabine. CD40-activated macrophages rapidly infiltrated tumors, became tumoricidal, and facilitated the depletion of tumor stroma. Thus, cancer immune surveillance does not necessarily depend on therapy-induced T cells; rather, our findings demonstrate a CD40-dependent mechanism for targeting tumor stroma in the treatment of cancer. PMID:21436454

Prognostic value of inflammation-based markers in patients with pancreatic cancer administered gemcitabine and erlotinib.

PubMed

Lee, Jae Min; Lee, Hong Sik; Hyun, Jong Jin; Choi, Hyuk Soon; Kim, Eun Sun; Keum, Bora; Seo, Yeon Seok; Jeen, Yoon Tae; Chun, Hoon Jai; Um, Soon Ho; Kim, Chang Duck

2016-07-15

To evaluate the value of systemic inflammation-based markers as prognostic factors for advanced pancreatic cancer (PC). Data from 82 patients who underwent combination chemotherapy with gemcitabine and erlotinib for PC from 2011 to 2014 were collected retrospectively. Data that included the neutrophil-to-lymphocyte ratio (NLR), the platelet-to-lymphocyte ratio, and the C-reactive protein (CRP)-to-albumin (CRP/Alb) ratio were analyzed. Kaplan-Meier curves, and univariate and multivariate Cox proportional hazards regression analyses were used to identify the prognostic factors associated with progression-free survival (PFS) and overall survival (OS). The univariate analysis demonstrated the prognostic value of the NLR (P = 0.049) and the CRP/Alb ratio (P = 0.047) in relation to PFS, and a positive relationship between an increase in inflammation-based markers and a poor prognosis in relation to OS. The multivariate analysis determined that an increased NLR (hazard ratio = 2.76, 95%CI: 1.33-5.75, P = 0.007) is an independent prognostic factor for poor OS. There was no association between the PLR and the patients' prognoses in those who had received chemotherapy that comprised gemcitabine and erlotinib in combination. The Kaplan-Meier method and the log-rank test determined significantly worse outcomes in relation to PFS and OS in patients with an NLR > 5 or a CRP/Alb ratio > 5. Systemic inflammation-based markers, including increases in the NLR and the CRP/Alb ratio, may be useful for predicting PC prognoses.

Combination of anti-L1 cell adhesion molecule antibody and gemcitabine or cisplatin improves the therapeutic response of intrahepatic cholangiocarcinoma.

PubMed

Cho, Seulki; Lee, Tae Sup; Song, In Ho; Kim, A-Ram; Lee, Yoon-Jin; Kim, Haejung; Hwang, Haein; Jeong, Mun Sik; Kang, Seung Goo; Hong, Hyo Jeong

2017-01-01

Cholangiocarcinoma has a poor prognosis and is refractory to conventional chemotherapy and radiation therapy. Improving survival of patients with advanced cholangiocarcinoma urgently requires the development of new effective targeted therapies in combination with chemotherapy. We previously developed a human monoclonal antibody (mAb) Ab417 that binds to both the human and mouse L1 cell adhesion molecule (L1CAM) with high affinities. In the present study, we observed that Ab417 exhibited tumor targeting ability in biodistribution studies and dose-dependent tumor growth inhibition in an intrahepatic cholangiocarcinoma (Choi-CK) xenograft mouse model. Regarding the mechanism of action, Ab417 was internalized into the tumor cells and thereby down-regulated membrane L1CAM, and inhibited tumor growth by reducing tumor cell proliferation in vivo. Gemcitabine inhibited the tumor growth in a dose-dependent manner in the Choi-CK xenograft model. However, cisplatin inhibited the tumor growth moderately and not in a dose-dependent way, suggesting that the tumors may have developed resistance to apoptosis induced by cisplatin. Combined treatment with Ab417 and gemcitabine or cisplatin exerted enhanced tumor growth inhibition compared to treatment with antibody or drug alone. The results suggest that Ab417 in combination with chemotherapy may have potential as a new therapeutic regimen for cholangiocarcinoma. Our study is the first to show an enhanced therapeutic effect of a therapeutic antibody targeting L1CAM in combination with chemotherapy in cholangiocarcinoma models.

Efficacy of Capecitabine Plus Oxaliplatin Combination Chemotherapy for Advanced Pancreatic Cancer after Failure of First-Line Gemcitabine-Based Therapy.

PubMed

Chung, Kwang Hyun; Ryu, Ji Kon; Son, Jun Hyuk; Lee, Jae Woo; Jang, Dong Kee; Lee, Sang Hyub; Kim, Yong-Tae

2017-03-15

Second-line chemotherapy in patients with advanced pancreatic ductal adenocarcinoma (PDAC) that progresses following gemcitabine-based treatment has not been established. This study aimed to investigate the efficacy and safety of second-line combination chemotherapy with capecitabine and oxaliplatin (XELOX) in these patients. Between August 2011 and May 2014, all patients who received at least one cycle of XELOX (capecitabine, 1,000 mg/m 2 twice daily for 14 days; oxaliplatin, 130 mg/m 2 on day 1 of a 3-week cycle) combination chemotherapy for unresectable or recurrent PDAC were retrospectively recruited. The response was evaluated every 9 weeks, and the tumor response rate, progression-free survival and overall survival, and adverse events were assessed. Sixty-two patients were included; seven patients (11.3%) had a partial tumor response, and 20 patients (32.3%) had stable disease. The median progression-free and overall survival were 88 days (range, 35.1 to 140.9 days) and 158 days (range, 118.1 to 197.9 days), respectively. Patients who remained stable longer with frontline therapy (≥120 days) exhibited significantly longer progression-free and overall survival. The most common grade 3 to 4 adverse events in patients were vomiting (8.1%) and anorexia (6.5%). There was one treatment-related mortality caused by severe neutropenia and typhlitis. Second-line XELOX combination chemotherapy demonstrated an acceptable response and survival rate in patients with advanced PDAC who had failed gemcitabine-based chemotherapy.

Management of unresectable, locally advanced pancreatic adenocarcinoma.

PubMed

Salgado, M; Arévalo, S; Hernando, O; Martínez, A; Yaya, R; Hidalgo, M

2018-02-01

The diagnosis of unresectable locally advanced pancreatic adenocarcinoma (LAPC) requires confirmation, through imaging tests, of the unfeasibility of achieving a complete surgical resection, in the absence of metastatic spread. The increase in overall survival (OS), together with an appropriate symptom management is the therapeutic target in LAPC, maintaining an acceptable quality of life and, if possible, increasing the time until the appearance of metastasis. Chemoradiation (CRT) improves OS compared to best support treatment or radiotherapy (RT) but with greater toxicity. No significant increase in OS has been achieved with CRT when compared to chemotherapy (QT) alone in patients without disease progression after four months of treatment with QT. However, a significantly better local control, that is, a significant increase in the time to disease progression was associated with this approach. The greater effectiveness of the schemes FOLFIRINOX and gemcitabine (Gem) + Nab-paclitaxel compared to gemcitabine alone, has been extrapolated from metastatic disease to LAPC, representing a possible alternative for patients with good performance status (ECOG 0-1). In the absence of randomized clinical trials, Gem is the standard treatment in LAPC. If disease control is achieved after 4-6 cycles of QT, the use of CRT for consolidation can be considered an option vs QT treatment maintenance. Capecitabine has a better toxicity profile and effectiveness compared to gemcitabine as a radiosensitizer. After local progression, and without evidence of metastases, treatment with RT or CRT, in selected patients, can support to maintain the regional disease control.

Influence of power ultrasound application on mass transport and microstructure of orange peel during hot air drying

NASA Astrophysics Data System (ADS)

Ortuño, Carmen; Pérez-Munuera, Isabel; Puig, Ana; Riera, Enrique; Garcia-Perez, J. V.

2010-01-01

Power ultrasound application on convective drying of foodstuffs may be considered an emergent technology. This work deals with the influence of power ultrasound on drying of natural materials addressing the kinetic as well as the product's microstructure. Convective drying kinetics of orange peel slabs (thickness 5.95±0.41 mm) were carried out at 40 ∘C and 1 m/s with (US) and without (AIR) power ultrasound application. A diffusion model considering external resistance to mass transfer was considered to describe drying kinetics. Fresh, US and AIR dried samples were analyzed using Cryo-SEM. Results showed that drying kinetics of orange peel were significantly improved by the application of power ultrasound. From modeling, it was observed a significant (p¡0.05) increase in both mass transfer coefficient and effective moisture diffusivity. The effects on mass transfer properties were confirmed from microestructural observations. In the cuticle surface, the pores were obstructed by wax components scattering, which evidence the ultrasonic effects on the interfaces. The cells of the flavedo were compressed and large intercellular air spaces were generated in the albedo facilitating water transfer through it.

Cancer and intercellular cooperation

PubMed Central

Dieli, Anna Maria

2017-01-01

The major transitions approach in evolutionary biology has shown that the intercellular cooperation that characterizes multicellular organisms would never have emerged without some kind of multilevel selection. Relying on this view, the Evolutionary Somatic view of cancer considers cancer as a breakdown of intercellular cooperation and as a loss of the balance between selection processes that take place at different levels of organization (particularly single cell and individual organism). This seems an elegant unifying framework for healthy organism, carcinogenesis, tumour proliferation, metastasis and other phenomena such as ageing. However, the gene-centric version of Darwinian evolution, which is often adopted in cancer research, runs into empirical problems: proto-tumoural and tumoural features in precancerous cells that would undergo ‘natural selection’ have proved hard to demonstrate; cells are radically context-dependent, and some stages of cancer are poorly related to genetic change. Recent perspectives propose that breakdown of intercellular cooperation could depend on ‘fields’ and other higher-level phenomena, and could be even mutations independent. Indeed, the field would be the context, allowing (or preventing) genetic mutations to undergo an intra-organism process analogous to natural selection. The complexities surrounding somatic evolution call for integration between multiple incomplete frameworks for interpreting intercellular cooperation and its pathologies. PMID:29134064

Nal-IRI With 5-fluorouracil (5-FU) and Leucovorin or Gemcitabine Plus Cisplatin in Advanced Biliary-tract Cancer

ClinicalTrials.gov

2018-03-22

Adenocarcinoma Metastatic; Biliary Tract Cancer; Adenocarcinoma of the Biliary Tract; Adenocarinoma Locally Advanced; Non-Resectable Hepatocellular Carcinoma; Intrahepatic Bile Duct Carcinoma; Extrahepatic Bile Duct Carcinoma

Switch from intracellular to intercellular invasion during water stress-tolerant legume nodulation

PubMed Central

Goormachtig, Sofie; Capoen, Ward; James, Euan K.; Holsters, Marcelle

2004-01-01

Rhizobia colonize their legume hosts by different modes of entry while initiating symbiotic nitrogen fixation. Most legumes are invaded via growing root hairs by the root hair-curl mechanism, which involves epidermal cell responses. However, invasion of a number of tropical legumes happens through fissures at lateral root bases by cortical, intercellular crack entry. In the semiaquatic Sesbania rostrata, the bacteria entered via root hair curls under nonflooding conditions. Upon flooding, root hair growth was prevented, invasion on accessible root hairs was inhibited, and intercellular invasion was recruited. The plant hormone ethylene was involved in these processes. The occurrence of both invasion pathways on the same host plant enabled a comparison to be made of the structural requirements for the perception of nodulation factors, which were more stringent for the epidermal root hair invasion than for the cortical intercellular invasion at lateral root bases. PMID:15079070

Asymmetric homotypic interactions of the atypical cadherin Flamingo mediate intercellular polarity signaling

PubMed Central

Chen, Wei-Shen; Antic, Dragana; Matis, Maja; Logan, Catriona Y.; Povelones, Michael; Anderson, Graham; Nusse, Roel; Axelrod, Jeffrey D.

2008-01-01

Acquisition of planar cell polarity (PCP) in epithelia involves intercellular communication, during which cells align their polarity with that of their neighbors. The transmembrane proteins Frizzled (Fz) and Van Gogh (Vang) are essential components of the intercellular communication mechanism, as loss of either strongly perturbs the polarity of neighboring cells. How Fz and Vang communicate polarity information between neighboring cells is poorly understood. The atypical cadherin, Flamingo (Fmi), is implicated in this process, yet whether Fmi acts permissively as a scaffold, or instructively as a signal is unclear. Here, we provide evidence that Fmi functions instructively to mediate Fz-Vang intercellular signal relay, recruiting Fz and Vang to opposite sides of cell boundaries. We propose that two functional forms of Fmi, one of which is induced by and physically interacts with Fz, form cadherin homodimers that signal bidirectionally and asymmetrically, instructing unequal responses in adjacent cell membranes to establish molecular asymmetry. PMID:18555784

THE EFFECT OF SMOOTH MUSCLE ON THE INTERCELLULAR SPACES IN TOAD URINARY BLADDER

PubMed Central

DiBona, Donald R.; Civan, Mortimer M.

1970-01-01

Phase microscopy of toad urinary bladder has demonstrated that vasopressin can cause an enlargement of the epithelial intercellular spaces under conditions of no net transfer of water or sodium. The suggestion that this phenomenon is linked to the hormone's action as a smooth muscle relaxant has been tested and verified with the use of other agents effecting smooth muscle: atropine and adenine compounds (relaxants), K+ and acetylcholine (contractants). Furthermore, it was possible to reduce the size and number of intercellular spaces, relative to a control, while increasing the rate of osmotic water flow. A method for quantifying these results has been developed and shows that they are, indeed, significant. It is concluded, therefore, that the configuration of intercellular spaces is not a reliable index of water flow across this epithelium and that such a morphologic-physiologic relationship is tenuous in any epithelium supported by a submucosa rich in smooth muscle. PMID:4915450

Gemcitabine Hydrochloride and Docetaxel With or Without Bevacizumab in Treating Patients With Advanced or Recurrent Uterine Leiomyosarcoma

ClinicalTrials.gov

2017-07-13

Recurrent Uterine Corpus Sarcoma; Stage IIIA Uterine Sarcoma; Stage IIIB Uterine Sarcoma; Stage IIIC Uterine Sarcoma; Stage IVA Uterine Sarcoma; Stage IVB Uterine Sarcoma; Uterine Corpus Leiomyosarcoma

Cancer Stem-Like Cells Enriched in Panc-1 Spheres Possess Increased Migration Ability and Resistance to Gemcitabine

PubMed Central

Yin, Tao; Wei, Hongji; Gou, Shanmiao; Shi, Pengfei; Yang, Zhiyong; Zhao, Gang; Wang, Chunyou

2011-01-01

Pancreatic cancer is one of the most lethal malignancies with poor prognosis. Previously, we found that a subpopulation of cancer stem cells (CSCs) in the Panc-1 pancreatic cancer cell line could propagate to form spheres. Here we characterized the malignant phenotypes of the pancreatic cancer stem CD44+/CD24+ cells, which were enriched under sphere forming conditions as analyzed by flow cytometry. These cells demonstrated increased resistance to gemcitabine and increased migration ability. Moreover, these cells exhibited epithelial to mesenchymal transition characterized by a decreased level of the epithelial marker E-cadherin and an increased level of the mesenchymal marker vimentin. Notably, abnormal expression of Bmi-1, ABCG2, Cyclin D1 and p16 were found in Panc-1 CSCs. Our results suggest that targeted inhibition of CSCs represents a novel therapeutic approach to overcome chemoresistance and metastasis of pancreatic cancer. PMID:21673909

Photothermal Effect Enhanced Cascade-Targeting Strategy for Improved Pancreatic Cancer Therapy by Gold Nanoshell@Mesoporous Silica Nanorod.

PubMed

Zhao, Ruifang; Han, Xuexiang; Li, Yiye; Wang, Hai; Ji, Tianjiao; Zhao, Yuliang; Nie, Guangjun

2017-08-22

Pancreatic cancer, one of the leading causes of cancer-related mortality, is characterized by desmoplasia and hypovascular cancerous tissue, with a 5 year survival rate of <8%. To overcome the severe resistance of pancreatic cancer to conventional therapies, we synthesized gold nanoshell-coated rod-like mesoporous silica (GNRS) nanoparticles which integrated cascade tumor targeting (mediated by photothermal effect and molecular receptor binding) and photothermal treatment-enhanced gemcitabine chemotherapy, under mild near-infrared laser irradiation condition. GNRS significantly improved gemcitabine penetration and accumulation in tumor tissues, thus destroying the dense stroma barrier of pancreatic cancer and reinforcing chemosensitivity in mice. Our current findings strongly support the notion that further development of this integrated plasmonic photothermal strategy may represent a promising translational nanoformulation for effective treatment of pancreatic cancer with integral cascade tumor targeting strategy and enhanced drug delivery efficacy.

Metastatic pancreatic adenocarcinoma and renal cell carcinoma treated with gemcitabine and sunitinib malate. A case report.

PubMed

Bharthuar, Anubha; Pearce, Lori; Litwin, Alan; LeVea, Charles; Kuvshinoff, Boris; Iyer, Renuka

2009-09-04

Pancreatic adenocarcinoma and renal cell carcinoma are relatively frequent cancers that have been rarely reported as synchronous primary malignancies. When present simultaneously, they pose a therapeutic challenge given the many available targeted agents with reported efficacy in renal cell cancer and limited options for metastatic pancreatic cancer. We report the case of a 43-year-old Caucasian gentleman diagnosed simultaneously with metastatic pancreatic adenocarcinoma and localized renal cell carcinoma treated with combination chemotherapy, consisting of gemcitabine and sunitinib. Patient had a radiographic response and prolonged progression free survival of twenty six weeks; side effects were manageable and included grade 3 neutropenia and grade 2 hypertension. This encouraging response, safety profile and progression free survival response suggest that we should further examine this and other such regimens to improve clinical outcomes for maximum efficacy with minimal side-effects.

[The role of meta-analysis in assessing the treatment of advanced non-small cell lung cancer].

PubMed

Pérol, M; Pérol, D

2004-02-01

Meta-analysis is a statistical method allowing an evaluation of the direction and quantitative importance of a treatment effect observed in randomized trials which have tested the treatment but have not provided a definitive conclusion. In the present review, we discuss the methodology and the contribution of meta-analyses to the treatment of advanced-stage or metastatic non-small-cell lung cancer. In this area of cancerology, meta-analyses have provided determining information demonstrating the impact of chemotherapy on patient survival. They have also helped define a two-drug regimen based on cisplatin as the gold standard treatment for patients with a satisfactory general status. Recently, the meta-analysis method was used to measure the influence of gemcitabin in combination with platinium salts and demonstrated a small but significant benefit in survival, confirming that gemcitabin remains the gold standard treatment in combination with cisplatin.

Personalising pancreas cancer treatment: When tissue is the issue.

PubMed

Sjoquist, Katrin M; Chin, Venessa T; Chantrill, Lorraine A; O'Connor, Chelsie; Hemmings, Chris; Chang, David K; Chou, Angela; Pajic, Marina; Johns, Amber L; Nagrial, Adnan M; Biankin, Andrew V; Yip, Desmond

2014-06-28

The treatment of advanced pancreatic cancer has not moved much beyond single agent gemcitabine until recently when protocols such as FOLFIRINOX (fluorouracil, leucovorin, irinotecan and oxaliplatin) and nab-paclitaxel-gemcitabine have demonstrated some improved outcomes. Advances in technology especially in massively parallel genome sequencing has progressed our understanding of the biology of pancreatic cancer especially the candidate signalling pathways that are involved in tumourogenesis and disease course. This has allowed identification of potentially actionable mutations that may be targeted by new biological agents. The heterogeneity of pancreatic cancer makes tumour tissue collection important with the aim of being able to personalise therapies for the individual as opposed to a one size fits all approach to treatment of the condition. This paper reviews the developments in this area of translational research and the ongoing clinical studies that will attempt to move this into the everyday oncology practice.

Understanding the Low Photosynthetic Rates of Sun and Shade Coffee Leaves: Bridging the Gap on the Relative Roles of Hydraulic, Diffusive and Biochemical Constraints to Photosynthesis

PubMed Central

Martins, Samuel C. V.; Galmés, Jeroni; Cavatte, Paulo C.; Pereira, Lucas F.; Ventrella, Marília C.; DaMatta, Fábio M.

2014-01-01

It has long been held that the low photosynthetic rates (A) of coffee leaves are largely associated with diffusive constraints to photosynthesis. However, the relative limitations of the stomata and mesophyll to the overall diffusional constraints to photosynthesis, as well as the coordination of leaf hydraulics with photosynthetic limitations, remain to be fully elucidated in coffee. Whether the low actual A under ambient CO2 concentrations is associated with the kinetic properties of Rubisco and high (photo)respiration rates also remains elusive. Here, we provide a holistic analysis to understand the causes associated with low A by measuring a variety of key anatomical/hydraulic and photosynthetic traits in sun- and shade-grown coffee plants. We demonstrate that leaf hydraulic architecture imposes a major constraint on the maximisation of the photosynthetic gas exchange of coffee leaves. Regardless of the light treatments, A was mainly limited by stomatal factors followed by similar limitations associated with the mesophyll and biochemical constraints. No evidence of an inefficient Rubisco was found; rather, we propose that coffee Rubisco is well tuned for operating at low chloroplastic CO2 concentrations. Finally, we contend that large diffusive resistance should lead to large CO2 drawdown from the intercellular airspaces to the sites of carboxylation, thus favouring the occurrence of relatively high photorespiration rates, which ultimately leads to further limitations to A. PMID:24743509

The Role of Oxygen in Avascular Tumor Growth

PubMed Central

Grimes, David Robert; Kannan, Pavitra; McIntyre, Alan; Kavanagh, Anthony; Siddiky, Abul; Wigfield, Simon; Harris, Adrian; Partridge, Mike

2016-01-01

The oxygen status of a tumor has significant clinical implications for treatment prognosis, with well-oxygenated subvolumes responding markedly better to radiotherapy than poorly supplied regions. Oxygen is essential for tumor growth, yet estimation of local oxygen distribution can be difficult to ascertain in situ, due to chaotic patterns of vasculature. It is possible to avoid this confounding influence by using avascular tumor models, such as tumor spheroids, a much better approximation of realistic tumor dynamics than monolayers, where oxygen supply can be described by diffusion alone. Similar to in situ tumours, spheroids exhibit an approximately sigmoidal growth curve, often approximated and fitted by logistic and Gompertzian sigmoid functions. These describe the basic rate of growth well, but do not offer an explicitly mechanistic explanation. This work examines the oxygen dynamics of spheroids and demonstrates that this growth can be derived mechanistically with cellular doubling time and oxygen consumption rate (OCR) being key parameters. The model is fitted to growth curves for a range of cell lines and derived values of OCR are validated using clinical measurement. Finally, we illustrate how changes in OCR due to gemcitabine treatment can be directly inferred using this model. PMID:27088720

Effects of reduced carbonic anhydrase activity on CO2 assimilation rates in Setaria viridis: a transgenic analysis.

PubMed

Osborn, Hannah L; Alonso-Cantabrana, Hugo; Sharwood, Robert E; Covshoff, Sarah; Evans, John R; Furbank, Robert T; von Caemmerer, Susanne

2017-01-01

In C 4 species, the major β-carbonic anhydrase (β-CA) localized in the mesophyll cytosol catalyses the hydration of CO 2 to HCO 3 - , which phosphoenolpyruvate carboxylase uses in the first step of C 4 photosynthesis. To address the role of CA in C 4 photosynthesis, we generated transgenic Setaria viridis depleted in β-CA. Independent lines were identified with as little as 13% of wild-type CA. No photosynthetic defect was observed in the transformed lines at ambient CO 2 partial pressure (pCO 2 ). At low pCO 2 , a strong correlation between CO 2 assimilation rates and CA hydration rates was observed. C 18 O 16 O isotope discrimination was used to estimate the mesophyll conductance to CO 2 diffusion from the intercellular air space to the mesophyll cytosol (g m ) in control plants, which allowed us to calculate CA activities in the mesophyll cytosol (C m ). This revealed a strong relationship between the initial slope of the response of the CO 2 assimilation rate to cytosolic pCO 2 (AC m ) and cytosolic CA activity. However, the relationship between the initial slope of the response of CO 2 assimilation to intercellular pCO 2 (AC i ) and cytosolic CA activity was curvilinear. This indicated that in S. viridis, mesophyll conductance may be a contributing limiting factor alongside CA activity to CO 2 assimilation rates at low pCO 2 . © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Quantitative Investigation of the Role of Intra-/Intercellular Dynamics in Bacterial Quorum Sensing.

PubMed

Leaman, Eric J; Geuther, Brian Q; Behkam, Bahareh

2018-04-20

Bacteria utilize diffusible signals to regulate population density-dependent coordinated gene expression in a process called quorum sensing (QS). While the intracellular regulatory mechanisms of QS are well-understood, the effect of spatiotemporal changes in the population configuration on the sensitivity and robustness of the QS response remains largely unexplored. Using a microfluidic device, we quantitatively characterized the emergent behavior of a population of swimming E. coli bacteria engineered with the lux QS system and a GFP reporter. We show that the QS activation time follows a power law with respect to bacterial population density, but this trend is disrupted significantly by microscale variations in population configuration and genetic circuit noise. We then developed a computational model that integrates population dynamics with genetic circuit dynamics to enable accurate (less than 7% error) quantitation of the bacterial QS activation time. Through modeling and experimental analyses, we show that changes in spatial configuration of swimming bacteria can drastically alter the QS activation time, by up to 22%. The integrative model developed herein also enables examination of the performance robustness of synthetic circuits with respect to growth rate, circuit sensitivity, and the population's initial size and spatial structure. Our framework facilitates quantitative tuning of microbial systems performance through rational engineering of synthetic ribosomal binding sites. We have demonstrated this through modulation of QS activation time over an order of magnitude. Altogether, we conclude that predictive engineering of QS-based bacterial systems requires not only the precise temporal modulation of gene expression (intracellular dynamics) but also accounting for the spatiotemporal changes in population configuration (intercellular dynamics).

Dose-finding trial of a combined regimen with bevacizumab, immunotherapy, and chemotherapy in patients with metastatic renal cell cancer: An Italian Oncology Group for Clinical Research (GOIRC) study.

PubMed

Buti, Sebastiano; Lazzarelli, Silvia; Chiesa, Matteo Dalla; Simonelli, Cecilia; Re, Giovanni Lo; Lheshi, Arvin; Simon, Spazzapan; Mattioli, Rodolfo; Caminiti, Caterina; Mazza, Giancarlo; Donini, Maddalena; Passalacqua, Rodolfo

2010-09-01

The aim of this study was to look for the maximum tolerated dose (MTD) of gemcitabine and 5-fluorouracil in a new regimen also containing the antiangiogenic bevacizumab and immunotherapy (IT) for the treatment of metastatic renal cell cancer. The primary objective of this multicenter dose-finding study was to establish the MTD of chemotherapy (CT) in combination with fixed doses of IT and bevacizumab. The secondary objective was to assess the combination's activity. Five escalated dose levels of CT with intravenous gemcitabine and 5-fluorouracil (days 1 and 8 every 28 d), were associated together with intravenous bevacizumab (10 mg/kg on days 1 and 15 every 28 d), subcutaneous interleukin-2 (1 MIU/m² bid on days 8, 9, 15, 16, and 1 MIU/m²/d on days 10-12 and 17-19), and interferon-α-2a (3 MIU on days 10, 12, 17, 19). Of the 27 enrolled patients, 59% had been pretreated. The MTD was not reached. The highest CT dose studied was gemcitabine 1000 mg/m² and 5-fluorouracil 600 mg/m². More frequent grade 3 to 4 toxicities included neutropenia (63%), thrombocytopenia (33%), and fever (26%). The response rate was 33% according to the Response Evaluation Criteria in Solid Tumors. This is the first study that explored the feasibility and safety of combined bevacizumab, IT, and CT in metastatic renal cell cancer. The activity of this regimen is interesting and its efficacy warrants further trials.

ATR inhibition broadly sensitizes ovarian cancer cells to chemotherapy independent of BRCA status

PubMed Central

Huntoon, Catherine J.; Flatten, Karen S.; Wahner Hendrickson, Andrea E.; Huehls, Amelia M.; Sutor, Shari L.; Kaufmann, Scott H.; Karnitz, Larry M.

2013-01-01

Replication stress and DNA damage activate the ATR-CHK1 checkpoint signaling pathway that licenses repair and cell survival processes. In this study, we examined the respective roles of the ATR and CHK1 kinases in ovarian cancer cells using genetic and pharmacological inhibitors of in combination with cisplatin, topotecan, gemcitabine and the poly(ADP-ribose)-polymerase (PARP) inhibitor veliparib (ABT-888), four agents with clinical activity in ovarian cancer. RNAi-mediated depletion or inhibition of ATR sensitized ovarian cancer cells to all four agents. In contrast, while cisplatin, topotecan and gemcitabine each activated CHK1, RNAi-mediated depletion or inhibition of this kinase in cells sensitized them only to gemcitabine. Unexpectedly, we found that neither the ATR kinase inhibitor VE-821 or the CHK1 inhibitor MK-8776 blocked ATR-mediated CHK1 phosphorylation or autophosphorylation, two commonly used readouts for inhibition of the ATR-CHK1 pathway. Instead, their ability to sensitize cells correlated with enhanced CDC25A levels. Additionally, we also found that VE-821 could further sensitize BRCA1-depleted cells to cisplatin, topotecan and veliparib beyond the potent sensitization already caused by their deficiency in homologous recombination. Taken together, our results established that ATR and CHK1 inhibitors differentially sensitize ovarian cancer cells to commonly used chemotherapy agents, and that CHK1 phosphorylation status may not offer a reliable marker for inhibition of the ATR-CHK1 pathway. A key implication of our work is the clinical rationale it provides to evaluate ATR inhibitors in combination with PARP inhibitors in BRCA1/2-deficient cells. PMID:23548269

Gemcitabine treatment of rat soft tissue sarcoma with phosphatidyldiglycerol-based thermosensitive liposomes.

PubMed

Limmer, Simone; Hahn, Jasmin; Schmidt, Rebecca; Wachholz, Kirsten; Zengerle, Anja; Lechner, Katharina; Eibl, Hansjörg; Issels, Rolf D; Hossann, Martin; Lindner, Lars H

2014-09-01

The pyrimidine analogue gemcitabine (dFdC) is frequently used in the treatment of patients with solid tumors. However, after i.v. application dFdC is rapidly inactivated by metabolization. Here, the potential of thermosensitive liposomes based on 1,2-dipalmitoyl-sn-glycero-3-phosphodiglycerol (DPPG2-TSL) were investigated as carrier and targeting system for delivery of dFdC in combination with local hyperthermia (HT). DPPG2-TSL were prepared by the lipid film hydration and extrusion method and characterized by dynamic light scattering, thin layer chromatography, phosphate assay and HPLC. In vivo experiments were performed in Brown Norway rats with a syngeneic soft tissue sarcoma. Local HT treatment was performed by light exposure. DPPG2-TSL were stable at 37°C in serum and showed a temperature dependent dFdC release >40°C. Plasma half-life of dFdC was strongly increased from 0.07 h (non-liposomal) to 0.53 h (liposomal, vesicle size 105 nm) or 2.59 h (liposomal, 129 nm). Therapy of BN175 tumors with dFdC encapsulated in DPPG2-TSL + HT showed significant improvement in tumor growth delay compared to non-liposomal dFdC without HT (p < 0.05), non-liposomal dFdC with HT (p < 0.01), and liposomal dFdC without HT (p < 0.05), respectively. Gemcitabine encapsulated in DPPG2-TSL in combination with local HT is a promising tool for the treatment of solid tumors. Therefore, these encouraging results ask for further investigation and evaluation.

Anti-carcinogenic effects of sulforaphane in association with its apoptosis-inducing and anti-inflammatory properties in human cervical cancer cells.

PubMed

Sharma, Chhavi; Sadrieh, Lida; Priyani, Anita; Ahmed, Musthaq; Hassan, Ahmad H; Hussain, Arif

2011-06-01

The multistep process of carcinogenesis is characterized by progressive disorganization and occurrence of initiation, promotion, and progression events. Several new strategies such as chemoprevention are being developed for treatment and prevention at various stages of carcinogenesis. Sulforaphane, a potential chemopreventive agent, possesses anti-proliferative, anti-inflammatory, anti-oxidant and anti-cancer activities and has attracted extensive interest for better cancer management. We evaluated the effect of sulforaphane alone or in combination with gemcitabine on HeLa cells by cell viability assay and confirmed the results by apoptosis assay. Further we analyzed the effect of sulforaphane on the expression of Bcl-2, COX-2 and IL-1β by RT-PCR on HeLa cells. In the present study, sulforaphane was found to induce dose-dependent selective cytotoxicity in HeLa cells in comparison to normal cells pointing to its safe cytotoxicity profile. Additionally, a combination of sulforaphane and gemcitabine was found to increase the growth inhibition in a synergistic manner in HeLa cells compared to the individual drugs. Also, the expression analysis of genes involved in apoptosis and inflammation revealed significant downregulation of Bcl-2, COX-2 and IL-1β upon treatment with sulforaphane. Our results suggest that sulforaphane exerts its anticancer activities via apoptosis induction and anti-inflammatory properties and provides the first evidence demonstrating synergism between sulforaphane and gemcitabine which may enhance the therapeutic index of prevention and/or treatment of cervical cancer. Copyright © 2010 Elsevier Ltd. All rights reserved.

Silencing of ATF2 inhibits growth of pancreatic cancer cells and enhances sensitivity to chemotherapy.

PubMed

Li, Mu; Wu, Xingda; Liu, Ning; Li, Xiaoying; Meng, Fanbin; Song, Shaowei

2017-06-01

Pancreatic cancer is one of the leading causes of cancer-related death worldwide. Activating transcription factor 2 (ATF2) is a multifunctional transcription factor, and is implicated in tumor progress, yet its role in pancreatic cancer remains unclear. In the present study, the level of ATF2 in pancreatic cancer tissues and the adjacent non-tumorous tissues was detected by quantitative real-time PCR and Western blot. The roles of ATF2 in the proliferation, cell cycle, and apoptosis of pancreatic cancer cells were investigated through ATF2 silencing, and the effect of ATF2 shRNA on the sensitivity of pancreatic cancer cells to gemcitabine, an anti-tumor drug, was explored. The results of our study showed that the ATF2 level in the pancreatic cancer tissues was higher than that in the adjacent non-tumorous tissues. Silencing of ATF2 was found to inhibit proliferation, arrest cell cycle at G1 phase and induce apoptosis in pancreatic cancer cells. Moreover, ATF2 silencing enhanced gemcitabine-induced growth-inhibition and apoptosis-induction effects in pancreatic cancer cells. In summary, silencing of ATF2 inhibited the growth of pancreatic cancer cells and enhanced the anti-tumor effects of gemcitabine, suggesting that ATF2 plays a pro-survival role in pancreatic cancer. Our results also propose that a high level of ATF2 may serve as a potential biomarker of pancreatic cancer, and that ATF2 may become a potential target for anti-tumor therapy. © 2017 International Federation for Cell Biology.

[Lung adenocarcinoma with concomitant EGFR mutation and ALK rearrangement].

PubMed

Caliez, J; Monnet, I; Pujals, A; Rousseau-Bussac, G; Jabot, L; Boudjemaa, A; Leroy, K; Chouaid, C

2017-05-01

Among patients with non-small-cell lung cancer, coexistence of EGFR mutation and ALK rearrangement is rare. We describe the clinical features of two patients with this double anomaly. A 62-year-old Caucasian non-smoking woman was diagnosed with cT4N0M0 lung adenocarcinoma. Initial biopsy showed EGFR mutation and ALK rearrangement. She received cisplatin-gemcitabine, followed by 17 months of gemcitabine. Owing to progression, she received erlotinib for 14 months, then paclitaxel for 6 months and finally crizotinib. A partial response was achieved and maintained for 24 months. A 45-year-old Caucasian woman, light smoker, was diagnosed with cT2N3M0 lung adenocarcinoma. Only EGFR mutation was found on initial analysis. She underwent treatment with cisplatin-gemcitabine and thoracic radiotherapy. Progression occurred after 8 months and afatinbib was started. Eight months later, progression was observed with a neoplasic pleural effusion in which tumor cells expressing ALK rearrangement were found. A new FISH analysis was performed on the initial tumor but did not find this rearrangement. Despite a third line of crizotinib, the patient died one month later. The literature shows 45 other cases of these two abnormalities, observed either from the start or during follow-up. EGFR's TKI were almost always given before ALK's TKI. Therapeutic strategy needs to be clarified in cases of double alteration. With regard to the second patient, appearance of ALK rearrangement may constitute a resistance mechanism to EGFR's TKI. Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.

Safety assessment of 4'-thio-beta-D-arabinofuranosylcytosine in the beagle dog suggests a drug-induced centrally mediated effect on the hypothalamic-pituitary-adrenal axis.

PubMed

Colagiovanni, Dorothy B; Drolet, Daniel W; Dihel, Larry; Meyer, Dennis J; Hart, Karen; Wolf, Julie

2006-01-01

4'-Thio-beta-D-arabinofuranosylcytosine (OSI-7836) is a nucleoside analogue with structural similarity to gemcitabine and cytarabine (ara-C). Myelosuppression, reversible transaminase elevations, and flu-like symptoms are common side effects associated with human use of gemcitabine and ara-C. Fatigue is also associated with the use of gemcitabine and OSI-7836 in humans. To better understand the toxicity of OSI-7836, subchronic studies were conducted in dogs. OSI-7836 was administered on days 1 and 8 or on days 1, 2, and 3 of a 21-day dose regimen. These schedules attempted to match clinical trial dosing regimens. Routine toxicity study end points demonstrated that OSI-7836 was primarily cytotoxic to the gastrointestinal tract, bone marrow, and testes; the myelotoxicity was mild and reversible. Plasma pharmacokinetics were dose-linear with an elimination half-life of 2.2 h. Follow-up single dose experiments in dogs assessed drug effects on lymphocyte subpopulations and on adrenal and thyroid function. Populations of T and B cells were equally reduced following OSI-7836 administration. There were no adverse effects on thyroid function, but there were marked reductions in circulating cortisol and adrenocorticotropic hormone concentrations suggesting a centrally mediated impairment of the hypothalamic-pituitary-adrenal axis. These findings show a toxicological profile with OSI-7836 similar to other nucleoside analogues and suggest that the beagle is a model for studying one possible cause of OSI-7836-related fatigue, impaired function of the hypothalamic-pituitary-adrenal axis.

Nano albumin bound-paclitaxel in pancreatic cancer: Current evidences and future directions

PubMed Central

Giordano, Guido; Pancione, Massimo; Olivieri, Nunzio; Parcesepe, Pietro; Velocci, Marianna; Di Raimo, Tania; Coppola, Luigi; Toffoli, Giuseppe; D’Andrea, Mario Rosario

2017-01-01

Pancreatic cancer (PDAC) is an aggressive and chemoresistant disease, representing the fourth cause of cancer related deaths in western countries. Majority of patients have unresectable, locally advanced or metastatic disease at time of diagnosis and the 5-year survival rate in these conditions is extremely low. For more than a decade gemcitabine has been the cornerstone of metastatic PDAC treatment, although survival benefit was very poor. PDAC cells are surrounded by an intense desmoplastic reaction that may create a barrier to the drugs penetration within the tumor. Recently PDAC stroma has been addressed as a potential therapeutic target. Nano albumin bound (Nab)-paclitaxel is an innovative molecule depleting tumor stroma, through interaction between albumin and secreted protein acidic and rich in cysteine. Addition of nab-paclitaxel to gemcitabine has showed activity and efficacy in metastatic PDAC first-line treatment improving survival and overall response rate vs gemcitabine alone in the MPACT phase III study. This combination represents one of the standards of care in advanced PDAC therapy and is suitable to a broader spectrum of patients compared to other schedules. Nab-paclitaxel is under investigation as a backbone of chemotherapy in novel combinations with target agents or immunotherapy in locally advanced or metastatic PDAC. In this article, we provide an updated and critical overview about the role of nab-paclitaxel in PDAC treatment based on the latest advances in preclinical and clinical research. Furthermore, we focus on the use of nab-paclitaxel within the context of metastatic PDAC treatment landscape and we discuss about future implications in the light of current clinical ongoing trials. PMID:28932079

Optimizing Adjuvant Therapy for Resected Pancreatic Cancer

Cancer.gov

In this clinical trial, patients with resected pancreatic head cancer will be randomly assigned to receive either gemcitabine with or without erlotinib for 5 treatment cycles. Patients who do not experience disease progression or recurrence will then be r

Cetuximab plus gemcitabine/oxaliplatin (GEMOXCET) in first-line metastatic pancreatic cancer: a multicentre phase II study

PubMed Central

Kullmann, F; Hollerbach, S; Dollinger, M M; Harder, J; Fuchs, M; Messmann, H; Trojan, J; Gäbele, E; Hinke, A; Hollerbach, C; Endlicher, E

2009-01-01

Targeting the epidermal growth factor receptor pathway in pancreatic cancer seems to be an attractive therapeutic approach. This study assessed the efficacy of cetuximab plus the combination of gemcitabine/oxaliplatin in metastatic pancreatic cancer. Eligible subjects had histological or cytological diagnosis of metastatic pancreatic adenocarcinoma. The primary end point was response according to RECIST. Patients received cetuximab 400 mg m−2 at first infusion followed by weekly 250 mg m−2 combined with gemcitabine 1000 mg m−2 as a 100 min infusion on day 1 and oxaliplatin 100 mg m−2 as a 2-h infusion on day 2 every 2 weeks. Between January 2005 and August 2006, a total of 64 patients (22 women (34%), 42 men (66%); median age 64 years (range 31–78)) were enrolled at seven study centres. On October 2007, a total of 17 patients were alive. Sixty-two patients were evaluable for baseline and 61 for assessment of response to treatment in an intention-to-treat analysis. Six patients had an incomplete drug combination within the first cycle of the treatment plan (n=4 hypersensitivity reactions to the first cetuximab infusion, n=2 refused to continue therapy). Reported grade 3/4 toxicities (% of patients) were leukopaenia 15%, anaemia 8%, thrombocytopaenia 10%, diarrhoea 7%, nausea 18%, infection 18% and allergy 7%. Cetuximab-attributable skin reactions occurred as follows: grade 0: 20%, grade 1: 41%, grade 2: 30% and grade 3: 10%. The intention-to-treat analysis of 61 evaluable patients showed an overall response rate of 33%, including 1 (2%) complete and 19 (31%) partial remissions. There were 31% patients with stable and 36% with progressive disease or discontinuation of the therapy before re-staging. The presence of a grade 2 or higher skin rash was associated with a higher likelihood of achieving objective response. Median time to progression was 118 days, with a median overall survival of 213 days. A clinical benefit response was noted in 24 of the evaluable 61 patients (39%). The addition of cetuximab to the combination of gemcitabine and oxaliplatin is well tolerated but does not increase response or survival in patients with metastatic pancreatic cancer. PMID:19293797

Effect of adjuvant chemotherapy with fluorouracil plus folinic acid or gemcitabine vs observation on survival in patients with resected periampullary adenocarcinoma: the ESPAC-3 periampullary cancer randomized trial.

PubMed

Neoptolemos, John P; Moore, Malcolm J; Cox, Trevor F; Valle, Juan W; Palmer, Daniel H; McDonald, Alexander C; Carter, Ross; Tebbutt, Niall C; Dervenis, Christos; Smith, David; Glimelius, Bengt; Charnley, Richard M; Lacaine, François; Scarfe, Andrew G; Middleton, Mark R; Anthoney, Alan; Ghaneh, Paula; Halloran, Christopher M; Lerch, Markus M; Oláh, Attila; Rawcliffe, Charlotte L; Verbeke, Caroline S; Campbell, Fiona; Büchler, Markus W

2012-07-11

Patients with periampullary adenocarcinomas undergo the same resectional surgery as that of patients with pancreatic ductal adenocarcinoma. Although adjuvant chemotherapy has been shown to have a survival benefit for pancreatic cancer, there have been no randomized trials for periampullary adenocarcinomas. To determine whether adjuvant chemotherapy (fluorouracil or gemcitabine) provides improved overall survival following resection. The European Study Group for Pancreatic Cancer (ESPAC)-3 periampullary trial, an open-label, phase 3, randomized controlled trial (July 2000-May 2008) in 100 centers in Europe, Australia, Japan, and Canada. Of the 428 patients included in the primary analysis, 297 had ampullary, 96 had bile duct, and 35 had other cancers. One hundred forty-four patients were assigned to the observation group, 143 patients to receive 20 mg/m2 of folinic acid via intravenous bolus injection followed by 425 mg/m2 of fluorouracil via intravenous bolus injection administered 1 to 5 days every 28 days, and 141 patients to receive 1000 mg/m2 of intravenous infusion of gemcitabine once a week for 3 of every 4 weeks for 6 months. The primary outcome measure was overall survival with chemotherapy vs no chemotherapy; secondary measures were chemotherapy type, toxic effects, progression-free survival, and quality of life. Eighty-eight patients (61%) in the observation group, 83 (58%) in the fluorouracil plus folinic acid group, and 73 (52%) in the gemcitabine group died. In the observation group, the median survival was 35.2 months (95%% CI, 27.2-43.0 months) and was 43.1 (95%, CI, 34.0-56.0) in the 2 chemotherapy groups (hazard ratio, 0.86; (95% CI, 0.66-1.11; χ2 = 1.33; P = .25). After adjusting for independent prognostic variables of age, bile duct cancer, poor tumor differentiation, and positive lymph nodes and after conducting multiple regression analysis, the hazard ratio for chemotherapy compared with observation was 0.75 (95% CI, 0.57-0.98; Wald χ2 = 4.53, P = .03). Among patients with resected periampullary adenocarcinoma, adjuvant chemotherapy, compared with observation, was not associated with a significant survival benefit in the primary analysis; however, multivariable analysis adjusting for prognostic variables demonstrated a statistically significant survival benefit associated with adjuvant chemotherapy. clinicaltrials.gov Identifier: NCT00058201.

Induction Chemotherapy With Gemcitabine, Oxaliplatin, and 5-Fluorouracil/Leucovorin Followed by Concomitant Chemoradiotherapy in Patients With Locally Advanced Pancreatic Cancer: A Taiwan Cooperative Oncology Group Phase II Study

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ch'ang, Hui-Ju; Department of Radiation Oncology, National Cheng Kung University Hospital, Tainan, Taiwan; Lin, Yu-Lin

Purpose: To evaluate the therapeutic efficacy of 3-month triplet induction chemotherapy (ICT) followed by concomitant chemoradiotherapy (CCRT) in patients with locally advanced pancreatic cancer (LAPC). Patients and Methods: Chemonaieve patients with measurable, histologically confirmed LAPC were eligible. The ICT consisted of biweekly gemcitabine (800 mg/m{sup 2}) infusion at a fixed dose rate (10 mg/m{sup 2}/min), followed by 85 mg/m{sup 2} oxaliplatin and 48-h infusion of 5-fluorouracil/leucovorin (3000/150 mg/m{sup 2}) for 6 cycles. Patients without disease progression 4 weeks after ICT would receive weekly 400 mg/m{sup 2} gemcitabine and 5040 cGy radiation in 28 fractions. After CCRT, patients were subjected formore » surgical intervention and/or maintenance chemotherapy until progression or intolerable toxicity. Results: Between December 2004 and August 2008, 50 patients were enrolled. The best responses after ICT were partial response (PR) in 9, stable disease in 26, and progressive disease or not evaluable in 15. Among the former 35 patients, 2 had disease progression before CCRT, and 3 declined to have CCRT. Of the 30 patients receiving CCRT, an additional 4 and 1 patient(s) achieved PR at the end of CCRT and during maintenance chemotherapy, respectively. On intent-to-treat analysis, the overall best response was PR in 14 patients and stable disease in 21. The overall response rate and disease control rate were 28% (95% confidence interval [CI], 16.2-42.5%) and 70% (95% CI, 44.4-99.2%), respectively. The median time to progression and overall survival of the intent-to-treat population was 9.3 (95% CI, 5.8-12.8) months and 14.5 (95% CI, 11.9-17.1) months, respectively. One- and two-year survival rates were 68% (95% CI, 55.1-80.9%) and 20.6% (95% CI, 8.7-32.5%), respectively. Neutropenia was the most common Grade 3-4 toxicity of both ICT and CCRT, with a frequency of 28% and 26.7%, respectively. Significant sensory neuropathy occurred in 9 patients (18%). Conclusion: Three months of triplet ICT followed by gemcitabine-based CCRT is feasible, moderately active, and associated with encouraging survival in patients with LAPC.« less

Patterning of wound-induced intercellular Ca2+ flashes in a developing epithelium

NASA Astrophysics Data System (ADS)

Narciso, Cody; Wu, Qinfeng; Brodskiy, Pavel; Garston, George; Baker, Ruth; Fletcher, Alexander; Zartman, Jeremiah

2015-10-01

Differential mechanical force distributions are increasingly recognized to provide important feedback into the control of an organ’s final size and shape. As a second messenger that integrates and relays mechanical information to the cell, calcium ions (Ca2+) are a prime candidate for providing important information on both the overall mechanical state of the tissue and resulting behavior at the individual-cell level during development. Still, how the spatiotemporal properties of Ca2+ transients reflect the underlying mechanical characteristics of tissues is still poorly understood. Here we use an established model system of an epithelial tissue, the Drosophila wing imaginal disc, to investigate how tissue properties impact the propagation of Ca2+ transients induced by laser ablation. The resulting intercellular Ca2+ flash is found to be mediated by inositol 1,4,5-trisphosphate and depends on gap junction communication. Further, we find that intercellular Ca2+ transients show spatially non-uniform characteristics across the proximal-distal axis of the larval wing imaginal disc, which exhibit a gradient in cell size and anisotropy. A computational model of Ca2+ transients is employed to identify the principle factors explaining the spatiotemporal patterning dynamics of intercellular Ca2+ flashes. The relative Ca2+ flash anisotropy is principally explained by local cell shape anisotropy. Further, Ca2+ velocities are relatively uniform throughout the wing disc, irrespective of cell size or anisotropy. This can be explained by the opposing effects of cell diameter and cell elongation on intercellular Ca2+ propagation. Thus, intercellular Ca2+ transients follow lines of mechanical tension at velocities that are largely independent of tissue heterogeneity and reflect the mechanical state of the underlying tissue.

Stimulating the Release of Exosomes Increases the Intercellular Transfer of Prions.

PubMed

Guo, Belinda B; Bellingham, Shayne A; Hill, Andrew F

2016-03-04

Exosomes are small extracellular vesicles released by cells and play important roles in intercellular communication and pathogen transfer. Exosomes have been implicated in several neurodegenerative diseases, including prion disease and Alzheimer disease. Prion disease arises upon misfolding of the normal cellular prion protein, PrP(C), into the disease-associated isoform, PrP(Sc). The disease has a unique transmissible etiology, and exosomes represent a novel and efficient method for prion transmission. The precise mechanism by which prions are transmitted from cell to cell remains to be fully elucidated, although three hypotheses have been proposed: direct cell-cell contact, tunneling nanotubes, and exosomes. Given the reported presence of exosomes in biological fluids and in the lipid and nucleic acid contents of exosomes, these vesicles represent an ideal mechanism for encapsulating prions and potential cofactors to facilitate prion transmission. This study investigates the relationship between exosome release and intercellular prion dissemination. Stimulation of exosome release through treatment with an ionophore, monensin, revealed a corresponding increase in intercellular transfer of prion infectivity. Conversely, inhibition of exosome release using GW4869 to target the neutral sphingomyelinase pathway induced a decrease in intercellular prion transmission. Further examination of the effect of monensin on PrP conversion revealed that monensin also alters the conformational stability of PrP(C), leading to increased generation of proteinase K-resistant prion protein. The findings presented here provide support for a positive relationship between exosome release and intercellular transfer of prion infectivity, highlighting an integral role for exosomes in facilitating the unique transmissible nature of prions. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

Intercellular communications-redox interactions in radiation toxicity; potential targets for radiation mitigation.

PubMed

Farhood, Bagher; Goradel, Nasser Hashemi; Mortezaee, Keywan; Khanlarkhani, Neda; Salehi, Ensieh; Nashtaei, Maryam Shabani; Shabeeb, Dheyauldeen; Musa, Ahmed Eleojo; Fallah, Hengameh; Najafi, Masoud

2018-06-17

Nowadays, using ionizing radiation (IR) is necessary for clinical, agricultural, nuclear energy or industrial applications. Accidental exposure to IR after a radiation terror or disaster poses a threat to human. In contrast to the old dogma of radiation toxicity, several experiments during the last two recent decades have revealed that intercellular signaling and communications play a key role in this procedure. Elevated level of cytokines and other intercellular signals increase oxidative damage and inflammatory responses via reduction/oxidation interactions (redox system). Intercellular signals induce production of free radicals and inflammatory mediators by some intermediate enzymes such as cyclooxygenase-2 (COX-2), nitric oxide synthase (NOS), NADPH oxidase, and also via triggering mitochondrial ROS. Furthermore, these signals facilitate cell to cell contact and increasing cell toxicity via cohort effect. Nitric oxide is a free radical with ability to act as an intercellular signal that induce DNA damage and changes in some signaling pathways in irradiated as well as non-irradiated adjacent cells. Targeting of these mediators by some anti-inflammatory agents or via antioxidants such as mitochondrial ROS scavengers opens a window to mitigate radiation toxicity after an accidental exposure. Experiments which have been done so far suggests that some cytokines such as IL-1β, TNF-α, TGF-β, IL-4 and IL-13 are some interesting targets that depend on irradiated organs and may help mitigate radiation toxicity. Moreover, animal experiments in recent years indicated that targeting of toll like receptors (TLRs) may be more useful for radioprotection and mitigation. In this review, we aimed to describe the role of intercellular interactions in oxidative injury, inflammation, cell death and killing effects of IR. Moreover, we described evidence on potential mitigation of radiation injury via targeting of these mediators.

Eribulin Mesylate and Gemcitabine Hydrochloride in Treating Patients With Metastatic Solid Tumors or Solid Tumors That Cannot be Removed by Surgery

ClinicalTrials.gov

2017-09-19

Adult Solid Neoplasm; Recurrent Ovarian Carcinoma; Recurrent Uterine Corpus Carcinoma; Stage III Ovarian Cancer; Stage III Uterine Corpus Cancer; Stage IV Ovarian Cancer; Stage IV Uterine Corpus Cancer

Patient Derived Cancer Cell Lines in Identifying Molecular Changes in Patients With Previously Untreated Pancreatic Cancer Receiving Gemcitabine Hydrochloride-Based Chemotherapy

ClinicalTrials.gov

2017-09-05

Pancreatic Ductal Adenocarcinoma; Stage IA Pancreatic Cancer; Stage IB Pancreatic Cancer; Stage IIA Pancreatic Cancer; Stage IIB Pancreatic Cancer; Stage III Pancreatic Cancer; Stage IV Pancreatic Cancer

An intercellular polyamine transfer via gap junctions regulates proliferation and response to stress in epithelial cells

PubMed Central

Desforges, Bénédicte; Curmi, Patrick A.; Bounedjah, Ouissame; Nakib, Samir; Hamon, Loic; De Bandt, Jean-Pascal; Pastré, David

2013-01-01

In the organism, quiescent epithelial cells have the potential to resume cycling as a result of various stimuli, including wound healing or oxidative stress. Because quiescent cells have a low polyamine level, resuming their growth requires an increase of their intracellular polyamine levels via de novo polyamine synthesis or their uptake from plasma. Another alternative, explored here, is an intercellular exchange with polyamine-rich cycling cells via gap junctions. We show that polyamines promote gap junction communication between proliferating cells by promoting dynamical microtubule plus ends at the cell periphery and thus allow polyamine exchange between cells. In this way, cycling cells favor regrowth in adjacent cells deprived of polyamines. In addition, intercellular interactions mediated by polyamines can coordinate the translational response to oxidative stress through the formation of stress granules. Some putative in vivo consequences of polyamine-mediated intercellular interactions are also discussed regarding cancer invasiveness and tissue regeneration. PMID:23515223

Host and viral RNA-binding proteins involved in membrane targeting, replication and intercellular movement of plant RNA virus genomes

PubMed Central

Hyodo, Kiwamu; Kaido, Masanori; Okuno, Tetsuro

2014-01-01

Many plant viruses have positive-strand RNA [(+)RNA] as their genome. Therefore, it is not surprising that RNA-binding proteins (RBPs) play important roles during (+)RNA virus infection in host plants. Increasing evidence demonstrates that viral and host RBPs play critical roles in multiple steps of the viral life cycle, including translation and replication of viral genomic RNAs, and their intra- and intercellular movement. Although studies focusing on the RNA-binding activities of viral and host proteins, and their associations with membrane targeting, and intercellular movement of viral genomes have been limited to a few viruses, these studies have provided important insights into the molecular mechanisms underlying the replication and movement of viral genomic RNAs. In this review, we briefly overview the currently defined roles of viral and host RBPs whose RNA-binding activity have been confirmed experimentally in association with their membrane targeting, and intercellular movement of plant RNA virus genomes. PMID:25071804

Pseudorabies Virus US3-Induced Tunneling Nanotubes Contain Stabilized Microtubules, Interact with Neighboring Cells via Cadherins, and Allow Intercellular Molecular Communication

PubMed Central

Jansens, Robert J. J.; Van den Broeck, Wim; De Pelsmaeker, Steffi; Lamote, Jochen A. S.; Van Waesberghe, Cliff; Couck, Liesbeth

2017-01-01

ABSTRACT Tunneling nanotubes (TNTs) are long bridge-like structures that connect eukaryotic cells and mediate intercellular communication. We found earlier that the conserved alphaherpesvirus US3 protein kinase induces long cell projections that contact distant cells and promote intercellular virus spread. In this report, we show that the US3-induced cell projections constitute TNTs. In addition, we report that US3-induced TNTs mediate intercellular transport of information (e.g., green fluorescent protein [GFP]) in the absence of other viral proteins. US3-induced TNTs are remarkably stable compared to most TNTs described in the literature. In line with this, US3-induced TNTs were found to contain stabilized (acetylated and detyrosinated) microtubules. Transmission electron microscopy showed that virus particles are individually transported in membrane-bound vesicles in US3-induced TNTs and are released along the TNT and at the contact area between a TNT and the adjacent cell. Contact between US3-induced TNTs and acceptor cells is very stable, which correlated with a marked enrichment in adherens junction components beta-catenin and E-cadherin at the contact area. These data provide new structural insights into US3-induced TNTs and how they may contribute to intercellular communication and alphaherpesvirus spread. IMPORTANCE Tunneling nanotubes (TNT) represent an important and yet still poorly understood mode of long-distance intercellular communication. We and others reported earlier that the conserved alphaherpesvirus US3 protein kinase induces long cellular protrusions in infected and transfected cells. Here, we show that US3-induced cell projections constitute TNTs, based on structural properties and transport of biomolecules. In addition, we report on different particular characteristics of US3-induced TNTs that help to explain their remarkable stability compared to physiological TNTs. In addition, transmission electron microscopy assays indicate that, in infected cells, virions travel in the US3-induced TNTs in membranous transport vesicles and leave the TNT via exocytosis. These data generate new fundamental insights into the biology of (US3-induced) TNTs and into how they may contribute to intercellular virus spread and communication. PMID:28747498

Connexin-Mediated Functional and Metabolic Coupling Between Astrocytes and Neurons.

PubMed

Mayorquin, Lady C; Rodriguez, Andrea V; Sutachan, Jhon-Jairo; Albarracín, Sonia L

2018-01-01

The central nervous system (CNS) requires sophisticated regulation of neuronal activity. This modulation is partly accomplished by non-neuronal cells, characterized by the presence of transmembrane gap junctions (GJs) and hemichannels (HCs). This allows small molecule diffusion to guarantee neuronal synaptic activity and plasticity. Astrocytes are metabolically and functionally coupled to neurons by the uptake, binding and recycling of neurotransmitters. In addition, astrocytes release metabolites, such as glutamate, glutamine, D-serine, adenosine triphosphate (ATP) and lactate, regulating synaptic activity and plasticity by pre- and postsynaptic mechanisms. Uncoupling neuroglial communication leads to alterations in synaptic transmission that can be detrimental to neuronal circuit function and behavior. Therefore, understanding the pathways and mechanisms involved in this intercellular communication is fundamental for the search of new targets that can be used for several neurological disease treatments. This review will focus on molecular mechanisms mediating physiological and pathological coupling between astrocytes and neurons through GJs and HCs.

Raindrops of synaptic noise on dual excitability landscape: an approach to astrocyte network modelling

NASA Astrophysics Data System (ADS)

Verisokin, Andrey Yu.; Postnov, Dmitry E.; Verveyko, Darya V.; Brazhe, Alexey R.

2018-04-01

The most abundant non-neuronal cells in the brain, astrocytes, populate all parts of the central nervous system (CNS). Astrocytic calcium activity ranging from subcellular sparkles to intercellular waves is believed to be the key to a plethora of regulatory pathways in the central nervous system from synaptic plasticity to blood flow regulation. Modeling of the calcium wave initiation and transmission and their spatiotemporal dynamics is therefore an important step stone in understanding the crucial cogs of cognition. Astrocytes are active sensors of ongoing neuronal and synaptic activity, and neurotransmitters diffusing from the synaptic cleft make a strong impact on the astrocytic activity. Here we propose a model describing the patterns of calcium wave formation at a single cell level and discuss the interplay between astrocyte shape the calcium waves dynamics driven by local stochastic surges of glutamate simulating synaptic activity.

Critical role of gap junction communication, calcium and nitric oxide signaling in bystander responses to focal photodynamic injury.

PubMed

Calì, Bianca; Ceolin, Stefano; Ceriani, Federico; Bortolozzi, Mario; Agnellini, Andrielly H R; Zorzi, Veronica; Predonzani, Andrea; Bronte, Vincenzo; Molon, Barbara; Mammano, Fabio

2015-04-30

Ionizing and nonionizing radiation affect not only directly targeted cells but also surrounding "bystander" cells. The underlying mechanisms and therapeutic role of bystander responses remain incompletely defined. Here we show that photosentizer activation in a single cell triggers apoptosis in bystander cancer cells, which are electrically coupled by gap junction channels and support the propagation of a Ca2+ wave initiated in the irradiated cell. The latter also acts as source of nitric oxide (NO) that diffuses to bystander cells, in which NO levels are further increased by a mechanism compatible with Ca(2+)-dependent enzymatic production. We detected similar signals in tumors grown in dorsal skinfold chambers applied to live mice. Pharmacological blockade of connexin channels significantly reduced the extent of apoptosis in bystander cells, consistent with a critical role played by intercellular communication, Ca2+ and NO in the bystander effects triggered by photodynamic therapy.

Stratum corneum drying drives vertical compression and lipid organization and improves barrier function in vitro.

PubMed

Iwai, Ichiro; Kunizawa, Naomi; Yagi, Eiichiro; Hirao, Tetsuji; Hatta, Ichiro

2013-03-27

The stratum corneum dehydrates after exogenous hydration due to skincare or bathing. In this study, sheets of stratum corneum were isolated from reconstructed human epidermis and the barrier function and structure of these sheets were assessed during drying with the aim of improving our understanding of skincare. Water diffusion through the sheets of stratum corneum decreased with drying, accompanied by decreased thickness and increased visible light transmission through the sheets. Electron paramagnetic resonance revealed that the order parameter values of stratum corneum lipids increased with drying. X-ray diffraction analysis revealed increases in the diffraction intensity of lamellar structures, with an 11-12 nm periodicity and spacing of 0.42 nm for lattice structures with drying. These results suggest that the drying process improves the barrier function of the stratum corneum by organizing the intercellular lipids in a vertically compressed arrangement.

Blood-Borne Macrophage-Neural Cell Interactions Hitchhike Endosome Networks for Cell-Based Nanozyme Brain Delivery

PubMed Central

Haney, Matthew J.; Suresh, Poornima; Zhao, Yuling; Kanmogne, Georgette D.; Kadiu, Irena; Sokolsky-Papkov, Marina; Klyachko, Natalia L.; Mosley, R. Lee; Kabanov, Alexander V.; Gendelman, Howard E.; Batrakova, Elena V.

2012-01-01

Background Macrophage carried nanoformulated catalase (“nanozyme”) attenuates neuroinflammation and protects nigrostriatal neurons from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine intoxication. This is facilitated by effective enzyme transfer from blood borne macrophages to adjacent endothelial cells and neurons leading to the decomposition of reactive oxygen species. Methods We now examine the intra- and intercellular trafficking mechanisms of nanozymes. Results In macrophages, nanozymes are internalized mainly by clathrin mediated endocytosis then traffic to recycling endosomes. The enzyme is subsequently released in exosomes facilitated by bridging conduits. Nanozyme transfer from macrophages to adjacent cells by endocytosis-independent mechanisms diffusing broadly throughout the recipient cells. In contrast, macrophage-free nanozymes are localized in lysosomes following endocytic entry. Conclusion Facilitated transfer of nanozyme from cell to cell can improve neuroprotection against oxidative stress commonly seen during neurodegenerative disease processes. PMID:22236307

Shape-Dependent Skin Penetration of Silver Nanoparticles: Does It Really Matter?

PubMed Central

Tak, Yu Kyung; Pal, Sukdeb; Naoghare, Pravin K.; Rangasamy, Sabarinathan; Song, Joon Myong

2015-01-01

Advancements in nano-structured materials have facilitated several applications of nanoparticles (NPs). Skin penetration of NPs is a crucial factor for designing suitable topical antibacterial agents with low systemic toxicity. Available reports focus on size-dependent skin penetration of NPs, mainly through follicular pathways. Herein, for the first time, we demonstrate a proof-of-concept study that entails variations in skin permeability and diffusion coefficients, penetration rates and depth-of-penetration of differently shaped silver NPs (AgNPs) via intercellular pathways using both in vitro and in vivo models. The antimicrobial activity of AgNPs is known. Different shapes of AgNPs may exhibit diverse antimicrobial activities and skin penetration capabilities depending upon their active metallic facets. Consideration of the shape dependency of AgNPs in antimicrobial formulations could help developing an ideal topical agent with the highest efficacy and low systemic toxicity. PMID:26584777

Coronary Heart Disease Alters Intercellular Communication by Modifying Microparticle-Mediated MicroRNA Transport

PubMed Central

Finn, Nnenna A.; Eapen, Danny; Manocha, Pankaj; Kassem, Hatem Al; Lassegue, Bernard; Ghasemzadeh, Nima; Quyyumi, Arshed; Searles, Charles D.

2013-01-01

Coronary heart disease (CHD) is characterized by abnormal intercellular communication and circulating microRNAs (miRNAs) are likely involved in this process. Here, we show that CHD was associated with changes in the transport of circulating miRNA, particularly decreased miRNA enrichment in microparticles (MPs). Additionally, MPs from CHD patients were less efficient at transferring miRNA to cultured HUVECs, which correlated with their diminished capacity to bind developmental endothelial locus-1 (Del-1). In summary, CHD was associated with distinct changes in circulating miRNA transport and these changes may contribute to the abnormal intercellular communication that underlies CHD initiation and progression. PMID:24042051

Connexin 32 and its derived homotypic gap junctional intercellular communication inhibit the migration and invasion of transfected HeLa cells via enhancement of intercellular adhesion.

PubMed

Yang, Jie; Liu, Bing; Wang, Qin; Yuan, Dongdong; Hong, Xiaoting; Yang, Yan; Tao, Liang

2011-01-01

The effects of connexin (Cx) and its derived homotypic gap junctional intercellular communication (GJIC) between tumor cells on the invasion of metastatic cancers and the underlying mechanisms remain unclear. In this study, we investigated the influence of Cx32 and the homotypic GJIC mediated by this Cx on the migration, invasion and intercellular adhesion of transfected HeLa cells. The expression of Cx32 significantly increased cell adhesion and inhibited migration and invasion. The inhibition of GJIC by oleamide, a widely used GJIC inhibitor, reduced the enhanced adhesion and partly reversed the decreased migration and invasion that had been induced by Cx32 expression. Blockage of the p38 and extracellular signal-regulated kinase 1 and 2 mitogen-activated protein kinase (ERK1/2 MAPKs) pathways using their specific inhibitors attenuated the effects of Cx32, but not those of GJIC, on cell adhesion, migration and invasion. These results indicate that the homotypic GJIC mediated by Cx32, as well as the Cx itself, inhibit cell migration and invasion, most likely through the elevation of intercellular adhesion. The suppressive effect of Cx32 on the migration and invasion of cancer cells, but not that of its derived homotypic GJIC, partly depends on the activation of the p38 and the ERK1/2 MAPKs pathways.

Reconstruction of palaeoatmospheric carbon dioxide using stomatal densities of various beech plants (Fagaceae): testing and application of a mechanistic model

NASA Astrophysics Data System (ADS)

Grein, M.; Roth-Nebelsick, A.; Konrad, W.

2006-12-01

A mechanistic model (Konrad &Roth-Nebelsick a, in prep.) was applied for the reconstruction of atmospheric carbon dioxide using stomatal densities and photosynthesis parameters of extant and fossil Fagaceae. The model is based on an approach which couples diffusion and the biochemical process of photosynthesis. Atmospheric CO2 is calculated on the basis of stomatal diffusion and photosynthesis parameters of the considered taxa. The considered species include the castanoid Castanea sativa, two quercoids Quercus petraea and Quercus rhenana and an intermediate species Eotrigonobalanus furcinervis. In the case of Quercus petraea literature data were used. Stomatal data of Eotrigonobalanus furcinervis, Quercus rhenana and Castanea sativa were determined by the authors. Data of the extant Castanea sativa were collected by applying a peeling method and by counting of stomatal densities on the digitalized images of the peels. Additionally, isotope data of leaf samples of Castanea sativa were determined to estimate the ratio of intercellular to ambient carbon dioxide. The CO2 values calculated by the model (on the basis of stomatal data and measured or estimated biochemical parameters) are in good agreement with literature data, with the exception of the Late Eocene. The results thus demonstrate that the applied approach is principally suitable for reconstructing palaeoatmospheric CO2.

EXPOSURE OF CULTURED MYOCYTES TO ZINC RESULTS IN ALTERED BEAT RATE AND INTERCELLULAR COMMUNICATION.

EPA Science Inventory

Exposure of cultured myocytes to zinc results in altered beat rate and intercellular communication

Graff, Donald W, Devlin, Robert B, Brackhan, Joseph A, Muller-Borer, Barbara J, Bowman, Jill S, Cascio, Wayne E.

Exposure to ambient air pollution particulate matter (...

Phase 2 Trial of Induction Gemcitabine, Oxaliplatin, and Cetuximab Followed by Selective Capecitabine-Based Chemoradiation in Patients With Borderline Resectable or Unresectable Locally Advanced Pancreatic Cancer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Esnaola, Nestor F.; Chaudhary, Uzair B.; O'Brien, Paul

Purpose: To evaluate, in a phase 2 study, the safety and efficacy of induction gemcitabine, oxaliplatin, and cetuximab followed by selective capecitabine-based chemoradiation in patients with borderline resectable or unresectable locally advanced pancreatic cancer (BRPC or LAPC, respectively). Methods and Materials: Patients received gemcitabine and oxaliplatin chemotherapy repeated every 14 days for 6 cycles, combined with weekly cetuximab. Patients were then restaged; “downstaged” patients with resectable disease underwent attempted resection. Remaining patients were treated with chemoradiation consisting of intensity modulated radiation therapy (54 Gy) and concurrent capecitabine; patients with borderline resectable disease or better at restaging underwent attempted resection. Results:more » A total of 39 patients were enrolled, of whom 37 were evaluable. Protocol treatment was generally well tolerated. Median follow-up for all patients was 11.9 months. Overall, 29.7% of patients underwent R0 surgical resection (69.2% of patients with BRPC; 8.3% of patients with LAPC). Overall 6-month progression-free survival (PFS) was 62%, and median PFS was 10.4 months. Median overall survival (OS) was 11.8 months. In patients with LAPC, median OS was 9.3 months; in patients with BRPC, median OS was 24.1 months. In the group of patients who underwent R0 resection (all of which were R0 resections), median survival had not yet been reached at the time of analysis. Conclusions: This regimen was well tolerated in patients with BRPC or LAPC, and almost one-third of patients underwent R0 resection. Although OS for the entire cohort was comparable to that in historical controls, PFS and OS in patients with BRPC and/or who underwent R0 resection was markedly improved.« less

Inhibition of glucose turnover by 3-bromopyruvate counteracts pancreatic cancer stem cell features and sensitizes cells to gemcitabine

PubMed Central

Bauer, Nathalie; Liu, Li; Fan, Pei; Zhang, Yiyao; Gladkich, Jury; Nwaeburu, Clifford C.; Mattern, Jürgen; Mollenhauer, Martin; Rückert, Felix; Zach, Sebastian; Haberkorn, Uwe; Gross, Wolfgang; Schönsiegel, Frank; Bazhin, Alexandr V.; Herr, Ingrid

2014-01-01

According to the cancer stem cell (CSC) hypothesis, the aggressive growth and early metastasis of pancreatic ductal adenocarcinoma (PDA) is due to the activity of CSCs, which are not targeted by current therapies. Otto Warburg suggested that the growth of cancer cells is driven by a high glucose metabolism. Here, we investigated whether glycolysis inhibition targets CSCs and thus may enhance therapeutic efficacy. Four established and 3 primary PDA cell lines, non-malignant cells, and 3 patient-tumor-derived CSC-enriched spheroidal cultures were analyzed by glucose turnover measurements, MTT and ATP assays, flow cytometry of ALDH1 activity and annexin positivity, colony and spheroid formation, western blotting, electrophoretic mobility shift assay, xenotransplantation, and immunohistochemistry. The effect of siRNA-mediated inhibition of LDH-A and LDH-B was also investigated. The PDA cells exhibited a high glucose metabolism, and glucose withdrawal or LDH inhibition by siRNA prevented growth and colony formation. Treatment with the anti-glycolytic agent 3-bromopyruvate almost completely blocked cell viability, self-renewal potential, NF-κB binding activity, and stem cell-related signaling and reverted gemcitabine resistance. 3-bromopyruvate was less effective in weakly malignant PDA cells and did not affect non-malignant cells, predicting minimal side effects. 3-bromopyruvate inhibited in vivo tumor engraftment and growth on chicken eggs and mice and enhanced the efficacy of gemcitabine by influencing the expression of markers of proliferation, apoptosis, self-renewal, and metastasis. Most importantly, primary CSC-enriched spheroidal cultures were eliminated by 3-bromopyruvate. These findings propose that CSCs may be specifically dependent on a high glucose turnover and suggest 3-bromopyruvate for therapeutic intervention. PMID:25015789