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Sample records for agent temozolomide tmz

  1. Effective sensitization of temozolomide by ABT-888 is lost with development of TMZ resistance in glioblastoma xenograft lines

    PubMed Central

    Clarke, Michelle J.; Mulligan, Evan A.; Grogan, Patrick T.; Mladek, Ann C.; Carlson, Brett L.; Schroeder, Mark A.; Curtin, Nicola J.; Lou, Zhenkun; Decker, Paul A.; Wu, Wenting; Plummer, E. Ruth; Sarkaria, Jann N.

    2009-01-01

    Resistance to temozolomide (TMZ) and radiotherapy (RT) is a major problem for patients with GBM but may be overcome using the PARP-inhibitor ABT-888. Using two primary GBM xenografts, the efficacy of ABT-888 combined with RT and/or TMZ was evaluated. Treatment with ABT-888 combined with TMZ resulted in significant survival prolongation (GBM12: 55.1%, p=0.005; GBM22: 54.4%, p=0.043). ABT-888 had no effect with RT alone, but significantly enhanced survival in GBM12 when combined with concurrent RT/TMZ. With multi-cycle therapy, ABT-888 further extended the survival benefit of TMZ in the inherently sensitive GBM12 and GBM22 xenograft lines. However, after in vivo selection for TMZ resistance, the derivative GBM12TMZ and GBM22TMZ lines were no longer sensitized by ABT-888 in combination with TMZ, and a similar lack of efficacy was observed in two other TMZ resistant tumor lines. Thus, the sensitizing effects of ABT-888 were limited to tumor lines that had not been previously exposed to TMZ, and these results suggest that patients with newly diagnosed GBM may be more likely to respond to combined TMZ/PARP inhibitor therapy than patients with recurrent disease. PMID:19174557

  2. Concomitant treatment of brain metastasis with Whole Brain Radiotherapy [WBRT] and Temozolomide [TMZ] is active and improves Quality of Life

    PubMed Central

    Addeo, Raffaele; Caraglia, Michele; Faiola, Vincenzo; Capasso, Elena; Vincenzi, Bruno; Montella, Liliana; Guarrasi, Rosario; Caserta, Luigi; Del Prete, Salvatore

    2007-01-01

    Background Brain metastases (BM) represent one of the most frequent complications related to cancer, and their treatment continues to evolve. We have evaluated the activity, toxicity and the impact on Quality of Life (QoL) of a concomitant treatment with whole brain radiotherapy (WBRT) and Temozolomide (TMZ) in patients with brain metastases from solid tumors in a prospective Simon two stage study. Methods Fifty-nine patients were enrolled and received 30 Gy WBRT with concomitant TMZ (75 mg/m2/day) for ten days, and subsequently TMZ (150 mg/m2/day) for up to six cycles. The primary end points were clinical symptoms and radiologic response. Results Five patients had a complete response, 21 patients had a partial response, while 18 patients had stable disease. The overall response rate (45%) exceeded the target activity per study design. The median time to progression was 9 months. Median overall survival was 13 months. The most frequent toxicities included grade 3 neutropenia (15%) and anemia (13%), and only one patient developed a grade 4 thrombocytopenia. Age, Karnofsky performance status, presence of extracranial metastases and the recursive partitioning analysis (RPA) were found to be predictive factors for response in patients. Overall survival (OS) and progression-free survival (PFS) were dependent on age and on the RPA class. Conclusion We conclude that this treatment is well tolerated, with an encouraging objective response rate, and a significant improvement in quality of life (p < 0.0001) demonstrated by FACT-G analysis. All patients answered the questionnaires and described themselves as 'independent' and able to act on their own initiatives. Our study found a high level of satisfaction for QoL, this provides useful information to share with patients in discussions regarding chemotherapy treatment of these lesions. PMID:17254350

  3. Effects of temozolomide (TMZ) on the expression and interaction of heat shock proteins (HSPs) and DNA repair proteins in human malignant glioma cells.

    PubMed

    Castro, Gisela Natalia; Cayado-Gutiérrez, Niubys; Zoppino, Felipe Carlos Martín; Fanelli, Mariel Andrea; Cuello-Carrión, Fernando Darío; Sottile, Mayra; Nadin, Silvina Beatriz; Ciocca, Daniel Ramón

    2015-03-01

    We previously reported the association of HSPA1A and HSPB1 with high-grade astrocytomas, suggesting that these proteins might be involved in disease outcome and response to treatment. With the aim to better understand the resistance/susceptibility processes associated to temozolomide (TMZ) treatment, the current study was performed in three human malignant glioma cell lines by focusing on several levels: (a) apoptotic index and senescence, (b) DNA damage, and (c) interaction of HSPB1 with players of the DNA damage response. Three human glioma cell lines, Gli36, U87, and DBTRG, were treated with TMZ evaluating cell viability and survival, apoptosis, senescence, and comets (comet assay). The expression of HSPA (HSPA1A and HSPA8), HSPB1, O6-methylguanine-DNA methyltransferase (MGMT), MLH1, and MSH2 was determined by immunocytochemistry, immunofluorescence, and Western blot. Immunoprecipitation was used to analyze protein interaction. The cell lines exhibited differences in viability, apoptosis, and senescence after TMZ administration. We then focused on Gli36 cells (relatively unstudied) which showed very low recovery capacity following TMZ treatment, and this was related to high DNA damage levels; however, the cells maintained their viability. In these cells, MGMT, MSH2, HSPA, and HSPB1 levels increased significantly after TMZ administration. In addition, MSH2 and HSPB1 proteins appeared co-localized by confocal microscopy. This co-localization increased after TMZ treatment, and in immunoprecipitation analysis, MSH2 and HSPB1 appeared interacting. In contrast, HSPB1 did not interact with MGMT. We show in glioma cells the biological effects of TMZ and how this drug affects the expression levels of heat shock proteins (HSPs), MGMT, MSH2, and MLH1. In Gli36 cells, the results suggest that interactions between HSPB1 and MSH2, including co-nuclear localization, may be important in determining cell sensitivity to TMZ. PMID:25155585

  4. An efficient and practical radiosynthesis of [11C]temozolomide

    PubMed Central

    Moseley, Christian K.; Carlin, Stephen M.; Neelamegam, Ramesh

    2014-01-01

    Temozolomide (TMZ) is a prodrug for an alkylating agent used for the treatment of malignant brain tumors. A positron emitting version, [11C]TMZ, has been utilized to help elucidate the mechanism and biodistribution of TMZ. Challenges in [11C]TMZ synthesis and reformulation make it difficult for routine production. Herein we report a highly reproducible one-pot radiosynthesis of [11C]TMZ with a radiochemical yield of 17±5% and >97% radiochemical purity. PMID:23151019

  5. Therapeutic effect of TMZ-POH on human nasopharyngeal carcinoma depends on reactive oxygen species accumulation.

    PubMed

    Xie, Li; Song, Xingguo; Guo, Wei; Wang, Xingwu; Wei, Ling; Li, Yang; Lv, Liyan; Wang, Weijun; Chen, Thomas C; Song, Xianrang

    2016-01-12

    Nasopharyngeal carcinoma (NPC) is a common head and neck malignancy without efficient chemotherapeutic agents for it. In our current study, we demonstrated the cytotoxicity effects of a newly patented compound temozolomide-perillyl alcohol (TMZ-POH) on NPC in vitro and in vivo, and the possible mechanisms involved. Human NPC cell lines CNE1, CNE2, HNE2, and SUME-α were treated with control (DMSO), TMZ, POH, TMZ plus POH, and TMZ-POH. Our data indicated that TMZ-POH could inhibit NPC cell proliferation, cause G2/M arrest and DNA damage. TMZ-POH triggered apoptosis in NPC cells via significant activation of caspase-3 and poly(ADP-ribose) polymerase (PARP). Importantly, TMZ-POH-induced cell death was found to be associated with (i) the loss of inner mitochondrial membrane potential (ΔΨm) and release of mitochondrial Cytochrome c, (ii) the increase in ROS generation, and (iii) the activation of stress-activated protein kinases (SAPK)/c-Jun N-terminal kinases (JNK) signaling pathway. The generation of ROS in response to TMZ-POH seems to play a crucial role in the cell death process since the blockage of ROS production using the antioxidant N-acetyl-L-cysteine or catalase reversed the TMZ-POH-induced JNK activation, DNA damage, and cancer cell apoptosis. These results provide the rationale for further research and preclinical investigation of the antitumor effect of TMZ-POH against human NPC. PMID:26625208

  6. Therapeutic effect of TMZ-POH on human nasopharyngeal carcinoma depends on reactive oxygen species accumulation.

    PubMed

    Xie, Li; Song, Xingguo; Guo, Wei; Wang, Xingwu; Wei, Ling; Li, Yang; Lv, Liyan; Wang, Weijun; Chen, Thomas C; Song, Xianrang

    2016-01-12

    Nasopharyngeal carcinoma (NPC) is a common head and neck malignancy without efficient chemotherapeutic agents for it. In our current study, we demonstrated the cytotoxicity effects of a newly patented compound temozolomide-perillyl alcohol (TMZ-POH) on NPC in vitro and in vivo, and the possible mechanisms involved. Human NPC cell lines CNE1, CNE2, HNE2, and SUME-α were treated with control (DMSO), TMZ, POH, TMZ plus POH, and TMZ-POH. Our data indicated that TMZ-POH could inhibit NPC cell proliferation, cause G2/M arrest and DNA damage. TMZ-POH triggered apoptosis in NPC cells via significant activation of caspase-3 and poly(ADP-ribose) polymerase (PARP). Importantly, TMZ-POH-induced cell death was found to be associated with (i) the loss of inner mitochondrial membrane potential (ΔΨm) and release of mitochondrial Cytochrome c, (ii) the increase in ROS generation, and (iii) the activation of stress-activated protein kinases (SAPK)/c-Jun N-terminal kinases (JNK) signaling pathway. The generation of ROS in response to TMZ-POH seems to play a crucial role in the cell death process since the blockage of ROS production using the antioxidant N-acetyl-L-cysteine or catalase reversed the TMZ-POH-induced JNK activation, DNA damage, and cancer cell apoptosis. These results provide the rationale for further research and preclinical investigation of the antitumor effect of TMZ-POH against human NPC.

  7. Targeting autophagy to sensitive glioma to temozolomide treatment.

    PubMed

    Yan, Yuanliang; Xu, Zhijie; Dai, Shuang; Qian, Long; Sun, Lunquan; Gong, Zhicheng

    2016-02-02

    Temozolomide (TMZ), an alkylating agent, is widely used for treating primary and recurrent high-grade gliomas. However, the efficacy of TMZ is often limited by the development of resistance. Recently, studies have found that TMZ treatment could induce autophagy, which contributes to therapy resistance in glioma. To enhance the benefit of TMZ in the treatment of glioblastomas, effective combination strategies are needed to sensitize glioblastoma cells to TMZ. In this regard, as autophagy could promote cell survival or autophagic cell death, modulating autophagy using a pharmacological inhibitor, such as chloroquine, or an inducer, such as rapamycin, has received considerably more attention. To understand the effectiveness of regulating autophagy in glioblastoma treatment, this review summarizes reports on glioblastoma treatments with TMZ and autophagic modulators from in vitro and in vivo studies, as well as clinical trials. Additionally, we discuss the possibility of using autophagy regulatory compounds that can sensitive TMZ treatment as a chemotherapy for glioma treatment.

  8. Temozolomide

    MedlinePlus

    ... by slowing or stopping the growth of cancer cells in your body. ... during, and after your treatment to check your body's response to temozolomide and to see if your blood cells are affected by this drug.Do not let ...

  9. Temozolomide competes for P-glycoprotein and contributes to chemoresistance in glioblastoma cells.

    PubMed

    Munoz, Jessian L; Walker, Nykia D; Scotto, Kathleen W; Rameshwar, Pranela

    2015-10-10

    Chemotherapeutic resistance can occur by P-glycoprotein (P-gp), a 12-transmembrane ATP-dependent drug efflux pump. Glioblastoma (GBM) has poor survival rate and uniformly acquired chemoresistance to its frontline agent, Temozolomide (TMZ). Despite much effort, overcoming TMZ resistance remains a challenge. We reported on autonomous induction of TMZ resistance by increased transcription MDR1, the gene for P-gp. This study investigated how P-gp and TMZ interact to gain resistance. Using an experimental model of Adriamycin-resistant DC3F cells (DC3F/Adx), we showed that increased P-gp caused TMZ resistance. Increasing concentrations of TMZ competed with Calcein for P-gp, resulting in reduced efflux in the DC3F/Adx cells. Three different inhibitors of P-gp reversed the resistance to TMZ in two different GBM cell lines, by increasing active Caspase 3. Molecular modeling predicted the binding sites to be the intracellular region of P-gp and also identified specific amino acids and kinetics of energy for the efflux of TMZ. Taken together, we confirmed P-gp targeting of TMZ, a crucial regulator of TMZ resistance in GBM. This study provides insights on the effectiveness by which TMZ competes with other P-gp substrates, thereby opening the door for combined targeted therapies.

  10. Adenovirus-Mediated FKHRL1/TM Sensitizes Melanoma Cells to Apoptosis Induced by Temozolomide

    PubMed Central

    Egger, Michael E.; McNally, Lacey R.; Nitz, Jonathan; McMasters, Kelly M.

    2014-01-01

    Abstract Melanoma exhibits variable resistance to the alkylating agent temozolomide (TMZ). We evaluated the potential of adenovirus expressing forkhead human transcription factor like 1 triple mutant (Ad-FKHRL1/TM) to sensitize melanoma cells to TMZ. Four melanoma cell lines were treated with Ad-FKHRL1/TM and TMZ, alone or in combination. Apoptosis was assessed by activation and inhibition of caspase pathway, nuclei fragmentation, and annexin V staining. The potential therapeutic efficacy of Ad-FKHRL1/TM with TMZ was also assessed in a mouse melanoma xenograft model. Combination therapy of Ad-FKHRL1/TM and TMZ resulted in greater cell killing (<20% cell viability) compared with single therapy and controls (p<0.05). Combination indices of Ad-FKHRL1/TM and TMZ therapy indicated significant (p<0.05) synergistic killing effect. Greater apoptosis induction was found in cells treated with Ad-FKHRL1/TM and TMZ than with Ad-FKHRL1/TM or TMZ-treated cells alone. Treatment with TMZ enhanced adenovirus transgene expression in a cell type-dependent manner. In an in vivo model, combination therapy of Ad-FKHRL1/TM with TMZ results in greater tumor growth reduction in comparison with single treatments. We suggest that Ad-FKHRL1/TM is a promising vector to sensitize melanoma cells to TMZ, and that a combination of both approaches would be effective in the clinical setting. PMID:25238278

  11. The Synergistic Effect of Combination Progesterone and Temozolomide on Human Glioblastoma Cells

    PubMed Central

    Atif, Fahim; Patel, Neil R.; Yousuf, Seema; Stein, Donald G.

    2015-01-01

    Glioblastoma multiforme (GBM) is the most common and most aggressive malignant brain tumor. Despite optimal treatment and evolving standard of care, the median survival of patients diagnosed with GBM is only 12–15 months. In this study, we combined progesterone (PROG) and temozolomide (TMZ), a standard chemotherapeutic agent for human GBM, to test whether PROG enhances the antitumor effects of TMZ and reduces its side effects. Two WHO grade IV human GBM cells lines (U87MG and U118MG) and primary human dermal fibroblasts (HDFs) were repeatedly exposed to PROG and TMZ either alone or in combination for 3 and 6 days. Cell death was measured by MTT reduction assay. PROG and TMZ individually induced tumor cell death in a dose-dependent manner. PROG at high doses produced more cell death than TMZ alone. When combined, PROG enhanced the cell death-inducing effect of TMZ. In HDFs, PROG did not reduce viability even at the same high cytotoxic doses, but TMZ did so in a dose-dependent manner. In combination, PROG reduced TMZ toxicity in HDFs. PROG alone and in combination with TMZ suppressed the EGFR/PI3K/Akt/mTOR signaling pathway and MGMT expression in U87MG cells, thus suppressing cell proliferation. PROG and TMZ individually reduced cell migration in U87MG cells but did so more effectively in combination. PROG enhances the cytotoxic effects of TMZ in GBM cells and reduces its toxic side effects in healthy primary cells. PMID:26110872

  12. Sulfasalazine intensifies temozolomide cytotoxicity in human glioblastoma cells.

    PubMed

    Ignarro, Raffaela Silvestre; Facchini, Gustavo; Vieira, André Schwambach; De Melo, Daniela Rodrigues; Lopes-Cendes, Iscia; Castilho, Roger Frigério; Rogerio, Fabio

    2016-07-01

    Temozolomide (TMZ) is an alkylating agent used to treat glioblastoma. This tumor type synthesizes the antioxidant glutathione through system X c (-) , which is inhibited by sulfasalazine (SAS). We exposed A172 and T98G human glioblastoma cells to a presumably clinically relevant concentration of TMZ (25 µM) and/or 0.5 mM SAS for 1, 3, or 5 days and assessed cell viability. For both cell lines, TMZ alone did not alter viability at any time point, while the coadministration of TMZ and SAS significantly reduced cell viability after 5 days. The drug combination exerted a synergistic effect on A172 cells after 3 and 5 days. Therefore, this particular lineage was subjected to complementary analyses on the genetic (transcriptome) and functional (glutathione and proliferating cell nuclear antigen (PCNA) protein) levels. Cellular pathways containing differentially expressed genes related to the cell cycle were modified by TMZ alone. On the other hand, SAS regulated pathways associated with glutathione metabolism and synthesis, irrespective of TMZ. Moreover, SAS, but not TMZ, depleted the total glutathione level. Compared with the vehicle-treated cells, the level of PCNA protein was lower in cells treated with TMZ alone or in combination with SAS. In conclusion, our data showed that the association of TMZ and SAS is cytotoxic to T98G and A172 cells, thus providing useful insights for improving TMZ clinical efficacy through testing this novel drug combination. Moreover, the present study not only reports original information on differential gene expression in glioblastoma cells exposed to TMZ and/or SAS but also describes an antiproliferative effect of TMZ, which has not yet been observed in A172 cells. PMID:27334753

  13. Sulfasalazine intensifies temozolomide cytotoxicity in human glioblastoma cells.

    PubMed

    Ignarro, Raffaela Silvestre; Facchini, Gustavo; Vieira, André Schwambach; De Melo, Daniela Rodrigues; Lopes-Cendes, Iscia; Castilho, Roger Frigério; Rogerio, Fabio

    2016-07-01

    Temozolomide (TMZ) is an alkylating agent used to treat glioblastoma. This tumor type synthesizes the antioxidant glutathione through system X c (-) , which is inhibited by sulfasalazine (SAS). We exposed A172 and T98G human glioblastoma cells to a presumably clinically relevant concentration of TMZ (25 µM) and/or 0.5 mM SAS for 1, 3, or 5 days and assessed cell viability. For both cell lines, TMZ alone did not alter viability at any time point, while the coadministration of TMZ and SAS significantly reduced cell viability after 5 days. The drug combination exerted a synergistic effect on A172 cells after 3 and 5 days. Therefore, this particular lineage was subjected to complementary analyses on the genetic (transcriptome) and functional (glutathione and proliferating cell nuclear antigen (PCNA) protein) levels. Cellular pathways containing differentially expressed genes related to the cell cycle were modified by TMZ alone. On the other hand, SAS regulated pathways associated with glutathione metabolism and synthesis, irrespective of TMZ. Moreover, SAS, but not TMZ, depleted the total glutathione level. Compared with the vehicle-treated cells, the level of PCNA protein was lower in cells treated with TMZ alone or in combination with SAS. In conclusion, our data showed that the association of TMZ and SAS is cytotoxic to T98G and A172 cells, thus providing useful insights for improving TMZ clinical efficacy through testing this novel drug combination. Moreover, the present study not only reports original information on differential gene expression in glioblastoma cells exposed to TMZ and/or SAS but also describes an antiproliferative effect of TMZ, which has not yet been observed in A172 cells.

  14. Preparation of Temozolomide-Loaded Nanoparticles for Glioblastoma Multiforme Targeting-Ideal Versus Reality.

    PubMed

    Lee, Chooi Yeng; Ooi, Ing Hong

    2016-01-01

    Temozolomide (TMZ) is one of the most effective chemotherapeutic agents for glioblastoma multiforme, but the required high administration dose is accompanied by side effects. To overcome this problem and to further improve TMZ's efficacy, targeted delivery of TMZ by using polymeric nanoparticles has been explored. We synthesised the PLGA-PEG-FOL copolymer and attempted encapsulation of TMZ into PLGA-PEG-FOL nanoparticles using the emulsion solvent evaporation method and the nanoprecipitation method. Conjugation of PEG and FOL to PLGA has been reported to be able to increase the delivery of TMZ to the brain as well as targeting the glioma cells. However, despite making numerous modifications to these methods, the loading of TMZ in the nanoparticles only ranged between 0.2% and 2%, and the nanoparticles were between 400 nm and 600 nm in size after freeze-drying. We proceed with determining the release profile of TMZ in phosphate buffered saline (PBS). Our initial data indicated that TMZ was slowly released from the nanoparticles. The metabolite of TMZ rather than the parent compound was detected in PBS. Our study suggests that while PLGA-PEG-FOL can be used as a polymeric or encapsulation material for central delivery of TMZ, a practical and cost effective formulation method is still far from reach. PMID:27618068

  15. Preparation of Temozolomide-Loaded Nanoparticles for Glioblastoma Multiforme Targeting-Ideal Versus Reality.

    PubMed

    Lee, Chooi Yeng; Ooi, Ing Hong

    2016-09-08

    Temozolomide (TMZ) is one of the most effective chemotherapeutic agents for glioblastoma multiforme, but the required high administration dose is accompanied by side effects. To overcome this problem and to further improve TMZ's efficacy, targeted delivery of TMZ by using polymeric nanoparticles has been explored. We synthesised the PLGA-PEG-FOL copolymer and attempted encapsulation of TMZ into PLGA-PEG-FOL nanoparticles using the emulsion solvent evaporation method and the nanoprecipitation method. Conjugation of PEG and FOL to PLGA has been reported to be able to increase the delivery of TMZ to the brain as well as targeting the glioma cells. However, despite making numerous modifications to these methods, the loading of TMZ in the nanoparticles only ranged between 0.2% and 2%, and the nanoparticles were between 400 nm and 600 nm in size after freeze-drying. We proceed with determining the release profile of TMZ in phosphate buffered saline (PBS). Our initial data indicated that TMZ was slowly released from the nanoparticles. The metabolite of TMZ rather than the parent compound was detected in PBS. Our study suggests that while PLGA-PEG-FOL can be used as a polymeric or encapsulation material for central delivery of TMZ, a practical and cost effective formulation method is still far from reach.

  16. Autophagy enhancement contributes to the synergistic effect of vitamin D in temozolomide-based glioblastoma chemotherapy

    PubMed Central

    BAK, DONG-HO; KANG, SEONG HEE; CHOI, DU RI; GIL, MI NA; YU, KWANG SIK; JEONG, JI HEUN; LEE, NAM-SEOB; LEE, JE-HUN; JEONG, YOUNG-GIL; KIM, DONG KWAN; KIM, DO-KYUNG; KIM, JWA-JIN; HAN, SEUNG-YUN

    2016-01-01

    Temozolomide (TMZ), an alkylating agent, is recommended as the initial treatment for high-grade glioblastoma. TMZ is widely used, but its short half-life and the frequency of tumor resistance limit its therapeutic efficacy. In the present study, the anticancer effect of vitamin D (VD) combined with TMZ upon glioblastoma was determined, and the underlying mechanism of this effect was identified. Through cell viability, clonogenic and wound healing assays, the current study demonstrated that treatment of a C6 glioblastoma cell line with TMZ and VD resulted in significantly increased in vitro antitumor effects compared with either VD or TMZ alone. Autophagy, hypothesized to be the dominant mechanism underlying TMZ-based tumor cell death, was maximally activated in TMZ and VD co-treated C6 cells. This was demonstrated by ultrastructural observations of autophagosomes, increased size and number of microtubule-associated protein 1 light chain 3 (LC3) puncta and increased conversion of LC3-I to LC3-II. However, the extent of apoptosis was not significantly different between cells treated with TMZ and VD and those treated with TMZ alone. Addition of the autophagy inhibitor 3-methyladenine markedly inhibited the anticancer effect of TMZ and VD treatment, indicating that the chemosensitizing effect of VD in TMZ-based glioblastoma therapy is generated through enhancement of cytotoxic autophagy. TMZ and VD co-treatment also significantly inhibited tumor progression and prolonged survival duration in rat glioblastoma orthotopic xenograft models when compared with TMZ treatment alone. These in vivo results are concordant with the aforementioned in vitro results, together revealing that the combined use of TMZ and VD exerts synergistic antitumor effects on rat models of glioblastoma and may represent an effective therapeutic strategy. PMID:27313664

  17. Preparation of Temozolomide-Loaded Nanoparticles for Glioblastoma Multiforme Targeting—Ideal Versus Reality

    PubMed Central

    Lee, Chooi Yeng; Ooi, Ing Hong

    2016-01-01

    Temozolomide (TMZ) is one of the most effective chemotherapeutic agents for glioblastoma multiforme, but the required high administration dose is accompanied by side effects. To overcome this problem and to further improve TMZ’s efficacy, targeted delivery of TMZ by using polymeric nanoparticles has been explored. We synthesised the PLGA-PEG-FOL copolymer and attempted encapsulation of TMZ into PLGA-PEG-FOL nanoparticles using the emulsion solvent evaporation method and the nanoprecipitation method. Conjugation of PEG and FOL to PLGA has been reported to be able to increase the delivery of TMZ to the brain as well as targeting the glioma cells. However, despite making numerous modifications to these methods, the loading of TMZ in the nanoparticles only ranged between 0.2% and 2%, and the nanoparticles were between 400 nm and 600 nm in size after freeze-drying. We proceed with determining the release profile of TMZ in phosphate buffered saline (PBS). Our initial data indicated that TMZ was slowly released from the nanoparticles. The metabolite of TMZ rather than the parent compound was detected in PBS. Our study suggests that while PLGA-PEG-FOL can be used as a polymeric or encapsulation material for central delivery of TMZ, a practical and cost effective formulation method is still far from reach. PMID:27618068

  18. Temozolomide may induce cell cycle arrest by interacting with URG4/URGCP in SH-SY5Y neuroblastoma cells.

    PubMed

    Çıtışlı, Veli; Dodurga, Yavuz; Eroğlu, Canan; Seçme, Mücahit; Avcı, Çığır Biray; Şatıroğlu-Tufan, N Lale

    2015-09-01

    Temozolomide (TMZ) is an alkylating drug used usually in glioma treatment by inducing the apoptosis in glioma cell. The aim of the study is to investigate the anticancer mechanism of TMZ in SH-SY5Y human neuroblastoma cell line. Cytotoxic effects of TMZ were determined by using XTT assay. IC50 doses in the SH-SY5Y were detected as 5 mM. Expression profiles of novel genes URG4/URGCP, CCND1, CCND2, CDK4, and BCL2 were determined by real-time PCR. The apoptotic effects of TMZ were evaluated with TUNEL method. Furthermore, effects of TMZ on colony formation and invasion were investigated in this study. It was observed that TMZ in SH-SY5Y cell line caused a significant decrease in the gene expressions of URG4/URGCP, CCND1, CCND2, CDK4, and BCL2. According to TUNEL assay results, TMZ markedly induced apoptosis in SH-SY5Y cell line. It was found that TMZ in SH-SY5Y cell line suppressed invasion and colony formation using matrigel invasion chamber and colony formation assay, respectively. To conclude, it is thought that TMZ demonstrates anticarcinogenesis activity by affecting cell cycle arrest, apoptosis, invasion, and colony formation on SH-SY5Y cells. TMZ may be an effective agent for treatment of neuroblastoma as a single or in combination with other drugs.

  19. A New Epigenetic Mechanism of Temozolomide Action in Glioma Cells

    PubMed Central

    Barciszewska, Anna-Maria; Gurda, Dorota; Głodowicz, Paweł; Nowak, Stanisław; Naskręt-Barciszewska, Mirosława Z

    2015-01-01

    Temozolomide (TMZ) is an oral alkylating chemotherapeutic agent that prolongs the survival of patients with glioblastoma (GBM). Despite that high TMZ potential, progression of disease and recurrence are still observed. Therefore a better understanding of the mechanism of action of this drug is necessary and may allow more durable benefit from its anti-glioma properties. Using nucleotide post-labelling method and separation on thin-layer chromatography we measured of global changes of 5-methylcytosine (m5C) in DNA of glioma cells treated with TMZ. Although m5C is not a product of TMZ methylation reaction of DNA, we analysed the effects of the drug action on different glioma cell lines through global changes at the level of the DNA main epigenetic mark. The first effect of TMZ action we observed is DNA hypermethylation followed by global demethylation. Therefore an increase of DNA methylation and down regulation of some genes expression can be ascribed to activation of DNA methyltransferases (DNMTs). On the other hand hypomethylation is induced by oxidative stress and causes uncontrolled expression of pathologic protein genes. The results of brain tumours treatment with TMZ suggest the new mechanism of modulation epigenetic marker in cancer cells. A high TMZ concentration induced a significant increase of m5C content in DNA in the short time, but a low TMZ concentration at longer time hypomethylation is observed for whole range of TMZ concentrations. Therefore TMZ administration with low doses of the drug and short time should be considered as optimal therapy. PMID:26309255

  20. Ursolic acid attenuates temozolomide resistance in glioblastoma cells by downregulating O6-methylguanine-DNA methyltransferase (MGMT) expression

    PubMed Central

    Zhu, Zhongling; Du, Shuangshuang; Ding, Fengxia; Guo, Shanshan; Ying, Guoguang; Yan, Zhao

    2016-01-01

    The DNA-alkylating agent temozolomide (TMZ) is an effective chemotherapeutic agent against malignant glioma, including glioblastoma multiforme (GBM). However, the clinical efficacy of TMZ is limited in many patients because of O6-methylguanine-DNA methyltransferase (MGMT)-driven resistance. Thus, new strategies to overcome TMZ resistance are urgently needed. Ursolic acid (UA) is a naturally derived pentacyclic triterpene acid that exerts broad anticancer effects, and shows capability to cross the blood-brain barrier. In this study, we evaluated the possible synergistic effect of TMZ and UA in resistant GBM cell lines. The results showed that UA prevented the proliferation of resistant GBM cells in a concentration-dependent manner. Compared with TMZ or UA treatment alone, the combination treatment of TMZ and UA synergistically enhanced cytotoxicity and senescence in TMZ-resistant GBM cells. This effect was correlated with the downregulation of MGMT. Moreover, experimental results with an in vivo mouse xenograft model showed that the combination treatment of UA and TMZ reduced tumor volumes by depleting MGMT. Therefore, UA as both a monotherapy and a resensitizer, might be a candidate agent for patients with refractory malignant gliomas. PMID:27508051

  1. AI-29ANGIOGENIC SWITCH FROM VEGFR2/HIF1α IN NEWLY DIAGNOSED GLIOBLASTOMA (GB) TO CXCR4-SDF1 PATHWAY IN RECURRENT PAIRED TUMOR AFTER RADIOTHERAPY (RT)-TEMOZOLOMIDE (TMZ)

    PubMed Central

    Tabouret, Emeline; Tchoghandjian, Aurelie; Denicolai, Emilie; Delfino, Christine; Metellus, Philippe; Padovani, Laetitia; Nanni, Isabelle; Barrie, Maryline; Boucard, Celine; Ouafik, L'Houcine; Figarella-Branger, Dominique; Chinot, Olivier

    2014-01-01

    BACKGROUND: Angiogenesis is one of the key features of GB. Our objective was to explore the potential changes of angiogenic factors expression between initial diagnosis of GB and recurrence after RT/TMZ. METHODS: Paired frozen tumor tissues from both initial and recurrent surgery were available for 29 patients with GB treated with RT/TMZ without bevacizumab upfront. Screening of over 150 genes expressions related to angiogenesis was performed on first 10 paired samples, using RT- PCR arrays (Qiagen®). Comparative expressions were determined using Qiagen® software. In a second step, RNA expressions of the selected identified genes were analyzed on all samples (29 paired tumors) using quantitative RT-PCR (qRT-PCR). Protein expression was examined by immunohistochemistry (IHC) with a semi-quantitative measure. Anti-tumoral effect of an anti-CXCR4 (AMD3100) in addition to TMZ and RT was tested in GB explants. RESULTS: In the screening step performed by RT-PCR arrays the initial-recurrence expression changes contributed to a selection of seven genes for which expression was then quantified by qRT-PCR: VEGFA, VEGFR2, VEGFR1, SDF1, CXCR4, uPA and HIF1α. From initial diagnosis to recurrence RNA expressions of CXCR4 (p = 0.029) and SDF1 (p = 0.107) were increased while expressions of HIF1α (p = 0.009) and VEGFR2 (p = 0.081) were decreased. Similarly, SDF1 protein expression (IHC) tended to increased (p = 0.096) while VEGFR2 staining was significantly decreased (p = 0.004) at recurrence. The role of CXCL4 was further supported by an increase of anti-tumoral effect observed with the combination of AMD3100 and RT/TMZ versus RT/TMZ alone in GB explants. By multivariate analysis, VEGFR2 RNA initial and recurrence expression levels were significantly correlated respectively to initial overall survival (p = 0.019, Hazard ratio (HR) =3.650) and recurrent overall survival (p = 0.024, HR = 2.536). CONCLUSION: Recurrence of GB after chemo-radiation could be associated with a

  2. Effect of temozolomide on the viability of musculoskeletal sarcoma cells

    PubMed Central

    KUSABE, YUTA; KAWASHIMA, HIROYUKI; OGOSE, AKIRA; SASAKI, TARO; ARIIZUMI, TAKASHI; HOTTA, TETSUO; ENDO, NAOTO

    2015-01-01

    Musculoskeletal sarcomas (MSS) are a heterogeneous group of malignancies with relatively high mortality rates. The prognosis for patients with MSS is poor, with few drugs inducing measurable activity. Alkylating agents, namely ifosfamide and dacarbazine, which act nonspecifically on proliferating cells, are the typical therapy prescribed for advanced MSS. A novel alkylating agent, temozolomide (TMZ), has several advantages over existing alkylating agents. TMZ induces the formation of O6-methylguanine in DNA, thereby inducing mismatches during DNA replication and the subsequent activation of apoptotic pathways. However, due to conflicting data in the literature, the mechanism of TMZ action has remained elusive. Therefore, the present study aimed to evaluate apoptosis in MSS cells treated with TMZ, and to evaluate the correlation between TMZ action and survival pathways, including the phosphoinositide 3-kinase (PI3K)/Akt and extracellular signal-regulated kinase (ERK)1/2 mitogen activated protein kinase (MAPK) pathways. Cell proliferation was evaluated by performing an XTT (sodium 3′-[1-(phenylaminocarbonyl)-3,4-tetrazolium]-bis (4-methoxy-6-nitro) benzene sulfonic acid hydrate) assay. Apoptotic morphological changes, for example chromatin condensation, were evaluated by fluorescence confocal microscopy. The expression of the apoptosis-associated proteins caspase-3, poly adenosine diphosphate ribose polymerase (PARP), Akt and ERK1/2, was determined by western blotting. The results of the present study indicated that, in certain MSS cells, the IC50 value was lower than that in TMZ-sensitive U-87 MG cells. Furthermore, TMZ treatment was associated with apoptotic morphological changes and the expression levels of pro-apoptotic cleaved caspase-3 and PARP were also increased in TMZ-treated MSS cells. In addition, the results indicated that PI3K/Akt and ERK1/2 MAPK were constitutively phosphorylated in MSS cells, and phosphorylation of PI3K/Akt was suppressed in certain

  3. Cytotoxic Effects of Temozolomide and Radiation are Additive- and Schedule-Dependent

    SciTech Connect

    Chalmers, Anthony J.; Ruff, Elliot M.; Martindale, Christine; Lovegrove, Nadia; Short, Susan C.

    2009-12-01

    Purpose: Despite aggressive therapy comprising radical radiation and temozolomide (TMZ) chemotherapy, the prognosis for patients with glioblastoma multiforme (GBM) remains poor, particularly if tumors express O{sup 6}-methylguanine-DNA-methyltransferase (MGMT). The interactions between radiation and TMZ remain unclear and have important implications for scheduling and for developing strategies to improve outcomes. Methods and Materials: Factors determining the effects of combination therapy on clonogenic survival, cell-cycle checkpoint signaling and DNA repair were investigated in four human glioma cell lines (T98G, U373-MG, UVW, U87-MG). Results: Combining TMZ and radiation yielded additive cytotoxicity, but only when TMZ was delivered 72 h before radiation. Radiosensitization was not observed. TMZ induced G2/M cell-cycle arrest at 48-72 h, coincident with phosphorylation of Chk1 and Chk2. Additive G2/M arrest and Chk1/Chk2 phosphorylation was only observed when TMZ preceded radiation by 72 h. The ataxia-telangiectasia mutated (ATM) inhibitor KU-55933 increased radiation sensitivity and delayed repair of radiation-induced DNA breaks, but did not influence TMZ effects. The multiple kinase inhibitor caffeine enhanced the cytotoxicity of chemoradiation and exacerbated DNA damage. Conclusions: TMZ is not a radiosensitizing agent but yields additive cytotoxicity in combination with radiation. Our data indicate that TMZ treatment should commence at least 3 days before radiation to achieve maximum benefit. Activation of G2/M checkpoint signaling by TMZ and radiation has a cytoprotective effect that can be overcome by dual inhibition of ATM and ATR. More specific inhibition of checkpoint signaling will be required to increase treatment efficacy without exacerbating toxicity.

  4. Radiosensitizing effects of TMZ observed in vivo only in a subset of MGMT methylated GBM xenografts

    PubMed Central

    Carlson, Brett L.; Grogan, Patrick T.; Mladek, Ann C.; Schroeder, Mark A.; Kitange, Gaspar J.; Decker, Paul A.; Giannini, Caterina; Wu, Wenting; Ballman, Karla A.; James, C. David; Sarkaria, Jann N.

    2009-01-01

    Purpose Concurrent temozolomide (TMZ) and radiation therapy (RT) followed by adjuvant TMZ is standard treatment for patients with GBM, although the relative contribution of concurrent versus adjuvant TMZ is unknown. In this study, the efficacy of TMZ/RT was tested in a panel of 20 primary GBM xenografts. Methods and Materials Mice with intracranial xenografts were treated with TMZ, RT, TMZ/RT, or placebo. Survival ratio for a given treatment/line was defined as the ratio of median survival for treatment vs. placebo. Results The median survival ratio was significantly higher for MGMT methylated tumors versus unmethylated tumors following treatment with TMZ (median survival ratio 3.6 vs. 1.5, respectively; p=0.008) or TMZ/RT (5.7 vs. 2.3, respectively; p=0.001), but not RT alone (1.7 vs. 1.6; p=0.47). In an ANOVA analysis, MGMT methylation status and p53 mutation status were significantly associated with treatment response. In analyzing the additional survival benefit conferred specifically by combined therapy, only a subset (5 of 11) MGMT methylated tumors derived substantial additional benefit from combined therapy, while none of the MGMT unmethylated tumors did. Consistent with a true radiosensitizing effect of TMZ, sequential treatment, in which RT (week 1) was followed by TMZ (week 2), proved significantly less effective than TMZ followed by RT or concurrent TMZ / RT (survival ratios of 4.0, 9.6, and 12.9, respectively; p<0.0001). Conclusions Concurrent treatment with TMZ and RT provides significant survival benefit only in a subset of MGMT methylated tumors, and provides superior anti-tumor activity relative to sequential administration of RT and TMZ. PMID:19695438

  5. Temozolomide and carmustine cause large-scale heterochromatin reorganization in glioma cells

    SciTech Connect

    Papait, Roberto; Magrassi, Lorenzo; Rigamonti, Dorotea; Cattaneo, Elena

    2009-02-06

    Temozolomide (TMZ) and carmustine (BCNU), cancer-drugs usually used in the treatment of gliomas, are DNA-methylating agents producing O6-methylguanine. It has been shown that 06-methylguanine triggers DNA mismatch repair and in turn induce apoptosis and senescence, respectively, over a 4 and 6 days period [Y. Hirose, M.S. Berger, R.O. Pieper, p53 effects both the duration of G2/M arrest and the fate of temozolomide-treated human glioblastoma cells, Cancer Res. 61 (2001) 1957-1963; W. Roos, M. Baumgartner, B. Kaina, Apoptosis triggered by DNA damage O6-methylguanine in human lymphocytes requires DNA replication and is mediated by p53 and Fas/CD95/Apo-1, Oncogene 23 (2004) 359-367]. Here we show that TMZ and BCNU have an earlier effect on nuclear organization and chromatin structure. In particular, we report that TMZ and BCNU induce clustering of pericentromeric heterochromatin regions and increase the amount of heterochromatic proteins MeCP2 and HP1{alpha} bound to chromatin. These drugs also decrease global levels of histone H3 acetylation and increase levels of histone H3 trimethylated on lysine 9 (H3-triMeK9). These events precede the senescence status. We conclude that TMZ and BCNU efficacy in glioma treatment may implicate a first event characterized by changes in heterochromatin organization and its silencing which is then followed by apoptosis and senescence.

  6. Temozolomide nanoparticles for targeted glioblastoma therapy.

    PubMed

    Fang, Chen; Wang, Kui; Stephen, Zachary R; Mu, Qingxin; Kievit, Forrest M; Chiu, Daniel T; Press, Oliver W; Zhang, Miqin

    2015-04-01

    Glioblastoma (GBM) is a deadly and debilitating brain tumor with an abysmal prognosis. The standard therapy for GBM is surgery followed by radiation and chemotherapy with Temozolomide (TMZ). Treatment of GBMs remains a challenge, largely because of the fast degradation of TMZ, the inability to deliver an effective dose of TMZ to tumors, and a lack of target specificity that may cause systemic toxicity. Here, we present a simple method for synthesizing a nanoparticle-based carrier that can protect TMZ from rapid degradation in physiological solutions and can specifically deliver them to GBM cells through the mediation of a tumor-targeting peptide chlorotoxin (CTX). Our nanoparticle, namely NP-TMZ-CTX, had a hydrodynamic size of <100 nm, exhibited sustained stability in cell culture media for up to 2 weeks, and could accommodate stable drug loading. TMZ bound to nanoparticles showed a much higher stability at physiological pH, with a half-life 7-fold greater than that of free TMZ. NP-TMZ-CTX was able to target GBM cells and achieved 2-6-fold higher uptake and a 50-90% reduction of IC50 72 h post-treatment as compared to nontargeted NP-TMZ. NP-TMZ-CTX showed great promise in its ability to deliver a large therapeutic dose of TMZ to GBM cells and could serve as a template for targeted delivery of other therapeutics.

  7. Temozolomide Nanoparticles for Targeted Glioblastoma Therapy

    PubMed Central

    Fang, Chen; Wang, Kui; Stephen, Zachary R.; Mu, Qingxin; Kievit, Forrest M.; Chiu, Daniel T.; Press, Oliver W.; Zhang, Miqin

    2015-01-01

    Glioblastoma (GBM) is a deadly and debilitating brain tumor with an abysmal prognosis. The standard therapy for GBM is surgery followed by radiation and chemotherapy with temozolomide (TMZ). Treatment of GBMs remains a challenge, largely due to the fast degradation of TMZ, inability to deliver an effective dose of TMZ to tumors, and lack of target specificity which may cause systemic toxicity. Here, we present a simple method to synthesize a nanoparticle-based carrier that can protect TMZ from rapid degradation in physiological solutions and can specifically deliver them to GBM cells through the mediation of a tumor targeting peptide chlorotoxin (CTX). Our nanoparticle, namely NP-TMZ-CTX, had a hydrodynamic size of less than 100 nm, exhibited sustained stability in cell culture media for up to two weeks, and could accommodate stable drug loading. TMZ bound to nanoparticles showed much higher stability at physiological pH, with a half-life 7-fold greater than free TMZ. NP-TMZ-CTX was able to target GBM cells and achieved 2–6-fold higher uptake and 50–90% reduction of IC50 at 72 h post-treatment as compared to non-targeted NP-TMZ. NP-TMZ-CTX showed great promise in its ability to deliver a high therapeutic dose of TMZ to GBM cells, and could serve as a template for targeted delivery of other therapeutics. PMID:25751368

  8. IGF-1R inhibition induces schedule-dependent sensitization of human melanoma to temozolomide.

    PubMed

    Ramcharan, Roger; Aleksic, Tamara; Kamdoum, Wilfride Petnga; Gao, Shan; Pfister, Sophia X; Tanner, Jordan; Bridges, Esther; Asher, Ruth; Watson, Amanda J; Margison, Geoffrey P; Woodcock, Mick; Repapi, Emmanouela; Li, Ji-Liang; Middleton, Mark R; Macaulay, Valentine M

    2015-11-24

    Prior studies implicate type 1 IGF receptor (IGF-1R) in mediating chemo-resistance. Here, we investigated whether IGF-1R influences response to temozolomide (TMZ), which generates DNA adducts that are removed by O6-methylguanine-DNA methyltransferase (MGMT), or persist causing replication-associated double-strand breaks (DSBs). Initial assessment in 10 melanoma cell lines revealed that TMZ resistance correlated with MGMT expression (r = 0.79, p = 0.009), and in MGMT-proficient cell lines, with phospho-IGF-1R (r = 0.81, p = 0.038), suggesting that TMZ resistance associates with IGF-1R activation. Next, effects of IGF-1R inhibitors (IGF-1Ri) AZ3801 and linsitinib (OSI-906) were tested on TMZ-sensitivity, cell cycle progression and DSB induction. IGF-1Ri sensitized BRAF wild-type and mutant melanoma cells to TMZ in vitro, an effect that was independent of MGMT. Cells harboring wild-type p53 were more sensitive to IGF-1Ri, and showed schedule-dependent chemo-sensitization that was most effective when IGF-1Ri followed TMZ. This sequence sensitized to clinically-achievable TMZ concentrations and enhanced TMZ-induced apoptosis. Simultaneous or prior IGF-1Ri caused less effective chemo-sensitization, associated with increased G1 population and reduced accumulation of TMZ-induced DSBs. Clinically relevant sequential (TMZ → IGF-1Ri) treatment was tested in mice bearing A375M (V600E BRAF, wild-type p53) melanoma xenografts, achieving peak plasma/tumor IGF-1Ri levels comparable to clinical Cmax, and inducing extensive intratumoral apoptosis. TMZ or IGF-1Ri caused minor inhibition of tumor growth (gradient reduction 13%, 25% respectively), while combination treatment caused supra-additive growth delay (72%) that was significantly different from control (p < 0.01), TMZ (p < 0.01) and IGF-1Ri (p < 0.05) groups. These data highlight the importance of scheduling when combining IGF-1Ri and other targeted agents with drugs that induce replication-associated DNA damage. PMID

  9. IGF-1R inhibition induces schedule-dependent sensitization of human melanoma to temozolomide

    PubMed Central

    Ramcharan, Roger; Aleksic, Tamara; Kamdoum, Wilfride Petnga; Gao, Shan; Pfister, Sophia X.; Tanner, Jordan; Bridges, Esther; Asher, Ruth; Watson, Amanda J.; Margison, Geoffrey P.; Woodcock, Mick; Repapi, Emmanouela; Li, Ji-Liang; Middleton, Mark R.; Macaulay, Valentine M.

    2015-01-01

    Prior studies implicate type 1 IGF receptor (IGF-1R) in mediating chemo-resistance. Here, we investigated whether IGF-1R influences response to temozolomide (TMZ), which generates DNA adducts that are removed by O6-methylguanine-DNA methyltransferase (MGMT), or persist causing replication-associated double-strand breaks (DSBs). Initial assessment in 10 melanoma cell lines revealed that TMZ resistance correlated with MGMT expression (r = 0.79, p = 0.009), and in MGMT-proficient cell lines, with phospho-IGF-1R (r = 0.81, p = 0.038), suggesting that TMZ resistance associates with IGF-1R activation. Next, effects of IGF-1R inhibitors (IGF-1Ri) AZ3801 and linsitinib (OSI-906) were tested on TMZ-sensitivity, cell cycle progression and DSB induction. IGF-1Ri sensitized BRAF wild-type and mutant melanoma cells to TMZ in vitro, an effect that was independent of MGMT. Cells harboring wild-type p53 were more sensitive to IGF-1Ri, and showed schedule-dependent chemo-sensitization that was most effective when IGF-1Ri followed TMZ. This sequence sensitized to clinically-achievable TMZ concentrations and enhanced TMZ-induced apoptosis. Simultaneous or prior IGF-1Ri caused less effective chemo-sensitization, associated with increased G1 population and reduced accumulation of TMZ-induced DSBs. Clinically relevant sequential (TMZ → IGF-1Ri) treatment was tested in mice bearing A375M (V600E BRAF, wild-type p53) melanoma xenografts, achieving peak plasma/tumor IGF-1Ri levels comparable to clinical Cmax, and inducing extensive intratumoral apoptosis. TMZ or IGF-1Ri caused minor inhibition of tumor growth (gradient reduction 13%, 25% respectively), while combination treatment caused supra-additive growth delay (72%) that was significantly different from control (p < 0.01), TMZ (p < 0.01) and IGF-1Ri (p < 0.05) groups. These data highlight the importance of scheduling when combining IGF-1Ri and other targeted agents with drugs that induce replication-associated DNA damage. PMID

  10. Potential Application of Temozolomide in Mesenchymal Stem Cell-Based TRAIL Gene Therapy Against Malignant Glioma

    PubMed Central

    Kim, Seong Muk; Woo, Ji Sun; Jeong, Chang Hyun; Ryu, Chung Heon; Jang, Jae-Deog

    2014-01-01

    Because the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively kills tumor cells, it is one of the most promising candidates for cancer treatment. TRAIL-secreting human mesenchymal stem cells (MSC-TRAIL) provide targeted and prolonged delivery of TRAIL in glioma therapy. However, acquired resistance to TRAIL of glioma cells is a major problem to be overcome. We showed a potential therapy that used MSC-TRAIL combined with the chemotherapeutic agent temozolomide (TMZ). The antitumor effects of the combination with MSC-TRAIL and TMZ on human glioma cells were determined by using an in vitro coculture system and an in vivo experimental xenografted mouse model. Intracellular signaling events that are responsible for the TMZ-mediated sensitization to TRAIL-induced apoptosis were also evaluated. Treatment of either TRAIL-sensitive or -resistant human glioma cells with TMZ and MSC-TRAIL resulted in a significant enhancement of apoptosis compared with the administration of each agent alone. We demonstrated that TMZ effectively increased the sensitivity to TRAIL-induced apoptosis via extracellular signal-regulated kinase-mediated upregulation of the death receptor 5 and downregulation of antiapoptotic proteins, such as X-linked inhibitor of apoptosis protein and cellular FLICE-inhibitory protein. Subsequently, this combined treatment resulted in a substantial increase in caspase activation. Furthermore, in vivo survival experiments and bioluminescence imaging analyses showed that treatment using MSC-TRAIL combined with TMZ had greater therapeutic efficacy than did single-agent treatments. These results suggest that the combination of clinically relevant TMZ and MSC-TRAIL is a potential therapeutic strategy for improving the treatment of malignant gliomas. PMID:24436439

  11. Combination Therapy for Gliomas Using Temozolomide and Interferon-Beta Secreting Human Bone Marrow Derived Mesenchymal Stem Cells

    PubMed Central

    Park, Jae-Hyun; Ryu, Chung Heon; Kim, Mi Jin

    2015-01-01

    Objective Malignant gliomas are the most common primary tumors of the central nervous system and the prognosis of patients with gliomas is poor. The combination of interferon-bata (IFN-β) and temozolomide (TMZ) has shown significant additive antitumor effects in human glioma xenograft models. Considering that the poor survival of patients with human malignant gliomas relates partly to the inability to deliver therapeutic agents to the tumor, the tropism of human bone marrow-derived mesenchymal stem cells (MSC) for malignant gliomas can be exploited to therapeutic advantages. We investigated the combination effects of TMZ and MSCs that secrete IFN-β on gliomas. Methods We engineered human MSCs to secret mouse IFN-β (MSC-IFN-β) via adenoviral transduction and confirmed their secretory capacity using enzyme-linked immunosorbent assays. In vitro and in vivo experiments were performed to determine the effects of the combined TMZ and MSC-IFN-β treatment. Results In vitro, the combination of MSC-IFN-β and TMZ showed significantly enhanced antitumor effects in GL26 mouse glioma cells. In vivo, the combined MSC-IFN-β and TMZ therapy significantly reduced the tumor size and improved the survival rates compared to each treatment alone. Conclusion These results suggest that MSCs can be used as an effective delivery vehicle so that the combination of MSC-IFN-β and TMZ could be considered as a new option for the treatment of malignant gliomas. PMID:26113958

  12. miR-487b-5p Regulates Temozolomide Resistance of Lung Cancer Cells Through LAMP2-Medicated Autophagy.

    PubMed

    Bao, Liang; Lv, Lei; Feng, Jinping; Chen, Yuyu; Wang, Xinhua; Han, Shuguang; Zhao, Hongqing

    2016-08-01

    Temozolomide (TMZ) is a standard agent used in the treatment of various types of cancers, including lung carcinoma, but TMZ resistance is common and accounts for many treatment failures. We investigated miRNA-487b-5p (miR-487b-5p) was highly expressed in A549 and H1299 cells which acquired TMZ resistance. Suppression of miR-487b-5p had overt effects on cellular proliferation and migration in the presence of TMZ. On the other hand, knockdown of miR-487b-5p resulted in increased survival and moderate tumor growth in vivo. In addition, the decreased cellular proliferation following miR-487b-5p suppression was linked to enhanced autophagy, evident by drastically increased levels of LC3-II, BECLIN1, and LAMP2 when miR-487b-5p was knocked down. Further analysis revealed that LAMP2 might be the target gene of miR-487b-5p. In conclusion, our study suggested that miR-487b-5p may be a potential biomarker of acquired TMZ resistance in lung cancer cells, and miR-487b-5p inhibition can be further explored as a chemotherapy target in the treatment of TMZ-resistant lung carcinoma.

  13. Combination of temozolomide and Taxol exerts a synergistic inhibitory effect on Taxol‑resistant glioma cells via inhibition of glucose metabolism.

    PubMed

    Guan, Ding-Guo; Chen, Han-Min; Liao, Sheng-Fang; Zhao, Tian-Zhi

    2015-11-01

    Malignant gliomas, which comprise the most common type of primary malignant brain tumor, are associated with a poor prognosis and quality of life. Paclitaxel (Taxol) and temozolomide (TMZ) are Food and Drug Administration‑approved anticancer agents, which are known to have therapeutic applications in various malignancies. However, similar to other chemotherapeutic agents, the development of resistance to TMZ and Taxol is common. The aim of the present study was to investigate the regulation of glucose metabolism by TMZ and Taxol in glioma cells. The results demonstrated that glioma cells exhibit decreased glucose uptake and lactate production in response to treatment with TMZ; however, glucose metabolism was increased in response to Taxol treatment. Following analysis of TMZ‑ and Taxol‑resistant cell lines, it was reported that glucose metabolism was decreased in the TMZ‑resistant cells, but was increased in the Taxol‑resistant cells. Notably, a combination of TMZ and Taxol exerted synergistic inhibitory effects on Taxol‑resistant glioma cells. However, the synergistic phenotype was not observed following treatment with a combination of 5‑fluorouracil and Taxol. Furthermore, restoration of glucose metabolism by overexpression of glucose transporter 1 in Taxol‑resistant cells resulted in regained resistance to Taxol. Therefore, the present study proposes a novel mechanism accounting for the synergistic effects of Taxol and TMZ co‑treatment, which may contribute to the development of therapeutic strategies for overcoming chemoresistance in patients with cancer.

  14. Therapeutic approach beyond conventional temozolomide for newly diagnosed glioblastoma: Review of the present evidence and future direction

    PubMed Central

    Mallick, Supriya; Gandhi, Ajeet Kumar; Rath, Goura Kishor

    2015-01-01

    Glioblastoma multiforme (GBM) is the most aggressive form of primary brain tumor. Maximal safe surgical resection followed by adjuvant partial brain radiation with concurrent and adjuvant temozolomide (TMZ) (oral alkylating agent) is the standard of care. Five years survival in TMZ treated patient reaches 9.8%. We aimed to summarize the changes in the management of GBM beyond conventional temozolomide based adjuvant treatment. We searched the PUBMED with the following key words: Glioblastoma, phase III trial, Phase II trial, adjuvant treatment in GBM. Clinical research has found a wide range of molecular aberrations in GBM and attempts are being made to further improve survival with the addition of different classes of drugs. Angiogenesis inhibitors, oncolytic vaccines, dose dense TMZ, and anti-epidermal growth factor receptor monoclonal antibody in phase III trials have failed to improve survival. Recent studies have also shown that the management strategies might be different and needs to be customized as per the age of patients such as pediatric and elderly patients. In addition, treatments should be personalized depending on the molecular aberrations. We reviewed all published phase III trials for newly diagnosed GBM as well as also looked into possible future directions in this review. Limited progress has happed beyond conventional TMZ in the adjuvant treatment of GBM. Newer insights are emerging about treatment intensification and introduction of newer molecular targeted drugs with more information about molecular aberrations. PMID:26811592

  15. KCa3.1 channel inhibition sensitizes malignant gliomas to temozolomide treatment

    PubMed Central

    D'Alessandro, Giuseppina; Grimaldi, Alfonso; Chece, Giuseppina; Porzia, Alessandra; Esposito, Vincenzo; Santoro, Antonio; Salvati, Maurizio; Mainiero, Fabrizio; Ragozzino, Davide; Angelantonio, Silvia Di; Wulff, Heike; Catalano, Myriam; Limatola, Cristina

    2016-01-01

    Malignant gliomas are among the most frequent and aggressive cerebral tumors, characterized by high proliferative and invasive indexes. Standard therapy for patients, after surgery and radiotherapy, consists of temozolomide (TMZ), a methylating agent that blocks tumor cell proliferation. Currently, there are no therapies aimed at reducing tumor cell invasion. Ion channels are candidate molecular targets involved in glioma cell migration and infiltration into the brain parenchyma. In this paper we demonstrate that: i) blockade of the calcium-activated potassium channel KCa3.1 with TRAM-34 has co-adjuvant effects with TMZ, reducing GL261 glioma cell migration, invasion and colony forming activity, increasing apoptosis, and forcing cells to pass the G2/M cell cycle phase, likely through cdc2 de-phosphorylation; ii) KCa3.1 silencing potentiates the inhibitory effect of TMZ on glioma cell viability; iii) the combination of TMZ/TRAM-34 attenuates the toxic effects of glioma conditioned medium on neuronal cultures, through a microglia dependent mechanism since the effect is abolished by clodronate-induced microglia killing; iv) TMZ/TRAM-34 co-treatment increases the number of apoptotic tumor cells, and the mean survival time in a syngeneic mouse glioma model (C57BL6 mice implanted with GL261 cells); v) TMZ/TRAM-34 co-treatment reduces cell viability of GBM cells and cancer stem cells (CSC) freshly isolated from patients. Taken together, these data suggest a new therapeutic approach for malignant glioma, targeting both glioma cell proliferating and migration, and demonstrate that TMZ/TRAM-34 co-treatment affects both glioma cells and infiltrating microglia, resulting in an overall reduction of tumor cell progression. PMID:27096953

  16. Erastin sensitizes glioblastoma cells to temozolomide by restraining xCT and cystathionine-γ-lyase function.

    PubMed

    Chen, Liangyu; Li, Xinxing; Liu, Libo; Yu, Bo; Xue, Yixue; Liu, Yunhui

    2015-03-01

    Glioblastoma multiforme (GBM) is one of the most common encephalic malignant tumors. Due to a high recurrence rate and a lack of effective treatments, the average survival rate remains low. Temozolomide (TMZ), a class of alkylating agent, is widely used as a first-line therapeutic drug during the adjuvant treatment for GBM patients. However, most patients exhibit a palpable resistance to TMZ treatment. Additionally, the underlying mechanism remains to be clarified. In this study, glutathione (GSH) and reactive oxygen species (ROS) levels were found to be closely associated with the sensitivity of GBM cells to TMZ. We also found that TMZ markedly induced xCT, the subunit of glutamate/cystine transporter system xc- expression, which together with the GSH synthesis was increased while the TMZ-inducible ROS level was decreased in GBM cells. In addition, the cystathionine γ-lyase (CTH) acivity, a key enzyme in the transsulfuration pathway was enhanced by TMZ, which insured a cysteine supply and GSH synthesis in a compensatory manner when xCT was blocked. Thus, the individual inhibition of xCT by siRNA and a pharmacological inhibitor (sulfasalazine) only partially inhibited GSH synthesis and moderately enhanced the GBM cell sensitivity to TMZ. However, the TMZ‑induced cytotoxicity was markedly increased along with a marked decrease in GSH levels as result of co-treatment with erastin, which inhibited cysteine uptake from xCT transporter and suppressed CTH activity, leading to impaired transformation from methionine to cysteine. In conclusion, to GBM therapy with a drug combination of TMZ and erastin may be beneficial.

  17. MEK2 is a prognostic marker and potential chemo-sensitizing target for glioma patients undergoing temozolomide treatment.

    PubMed

    He, Hua; Yao, Maojin; Zhang, Wenhao; Tao, Bangbao; Liu, Feili; Li, Shu; Dong, Yan; Zhang, Chenran; Meng, Yicheng; Li, Yuxin; Hu, Guohan; Luo, Chun; Zong, Hui; Lu, Yicheng

    2016-09-01

    Although temozolomide (TMZ) is the first-line chemotherapeutic agent for glioblastoma, it is often non-curative due to drug resistance. To overcome the resistance of glioblastoma cells to TMZ, it is imperative to identify prognostic markers for outcome prediction and to develop chemo-sensitizing agents. Here, the gene expression profiles of TMZ-resistant and TMZ-sensitive samples were compared by microarray analysis, and mitogen-activated protein kinase kinase 2 (MEK2) was upregulated specifically in resistant glioma cells but not in sensitive tumor cells or non-tumor tissues. Moreover, a comprehensive analysis of patient data revealed that the increased level of MEK2 expression correlated well with the advancement of glioma grade and worse prognosis in response to TMZ treatment. Furthermore, reducing the level of MEK2 in U251 glioma cell lines or xenografted glioma models through shRNA-mediated gene knockdown inhibited cell proliferation and enhanced the sensitivity of cells toward TMZ treatment. Further analysis of tumor samples from glioma patients by real-time PCR indicated that an increased MEK2 expression level was closely associated with the activation of many drug resistance genes. Finally, these resistance genes were downregulated after MEK2 was silenced in vitro, suggesting that the mechanism of MEK2-induced chemo-resistance could be mediated by the transcriptional activation of these resistance genes. Collectively, our data indicated that the expression level of MEK2 could serve as a prognostic marker for glioma chemotherapy and that MEK2 antagonists can be used as chemo-sensitizers to enhance the treatment efficacy of TMZ.

  18. MEK2 is a prognostic marker and potential chemo-sensitizing target for glioma patients undergoing temozolomide treatment

    PubMed Central

    He, Hua; Yao, Maojin; Zhang, Wenhao; Tao, Bangbao; Liu, Feili; Li, Shu; Dong, Yan; Zhang, Chenran; Meng, Yicheng; Li, Yuxin; Hu, Guohan; Luo, Chun; Zong, Hui; Lu, Yicheng

    2016-01-01

    Although temozolomide (TMZ) is the first-line chemotherapeutic agent for glioblastoma, it is often non-curative due to drug resistance. To overcome the resistance of glioblastoma cells to TMZ, it is imperative to identify prognostic markers for outcome prediction and to develop chemo-sensitizing agents. Here, the gene expression profiles of TMZ-resistant and TMZ-sensitive samples were compared by microarray analysis, and mitogen-activated protein kinase kinase 2 (MEK2) was upregulated specifically in resistant glioma cells but not in sensitive tumor cells or non-tumor tissues. Moreover, a comprehensive analysis of patient data revealed that the increased level of MEK2 expression correlated well with the advancement of glioma grade and worse prognosis in response to TMZ treatment. Furthermore, reducing the level of MEK2 in U251 glioma cell lines or xenografted glioma models through shRNA-mediated gene knockdown inhibited cell proliferation and enhanced the sensitivity of cells toward TMZ treatment. Further analysis of tumor samples from glioma patients by real-time PCR indicated that an increased MEK2 expression level was closely associated with the activation of many drug resistance genes. Finally, these resistance genes were downregulated after MEK2 was silenced in vitro, suggesting that the mechanism of MEK2-induced chemo-resistance could be mediated by the transcriptional activation of these resistance genes. Collectively, our data indicated that the expression level of MEK2 could serve as a prognostic marker for glioma chemotherapy and that MEK2 antagonists can be used as chemo-sensitizers to enhance the treatment efficacy of TMZ. PMID:26189368

  19. Knockdown of long noncoding RNA H19 sensitizes human glioma cells to temozolomide therapy.

    PubMed

    Jiang, Pengfei; Wang, Ping; Sun, Xiaoling; Yuan, Zhongshun; Zhan, Rucai; Ma, Xiangyu; Li, Weiguo

    2016-01-01

    Temozolomide (TMZ) is commonly used in glioma chemotherapy. However, a great clinical challenge for TMZ is chemoresistance. H19 transcripts are recognized as long noncoding RNAs, which potentially interact with chromatin-modifying complexes to regulate gene expression via epigenetic changes. Our data based on glioma patients showed that the expression of H19 was significantly upregulated in TMZ-resistant tumors compared with the TMZ-sensitive tumors. To determine the function of H19 in glioma, cell lines U87 and U251 were exposed to TMZ to establish TMZ-resistant clones U87(TMZ) and U251(TMZ). In U87(TMZ) and U251(TMZ), the expression level of H19 transcripts was increased compared to wild-type or nonresistant clones, as determined by real-time quantitative reverse transcription polymerase chain reaction. Concomitant treatment with small interfering RNA specifically targeting H19 and TMZ in resistant glioma clones resulted in decreased IC50 values for TMZ, and increased apoptotic rates than control small interfering RNA-treated cells. This was also evident by the increased PARP cleavage in resistant cells exposed to TMZ + si-H19. Furthermore, the reduced expression of H19 altered major drug resistance genes, such as MDR, MRP, and ABCG2, both at the mRNA and protein levels. Taken together, these findings suggest that H19 plays an important role in the development of TMZ resistance, and may represent a novel therapeutic target for TMZ-resistant gliomas. PMID:27366087

  20. Knockdown of long noncoding RNA H19 sensitizes human glioma cells to temozolomide therapy

    PubMed Central

    Jiang, Pengfei; Wang, Ping; Sun, Xiaoling; Yuan, Zhongshun; Zhan, Rucai; Ma, Xiangyu; Li, Weiguo

    2016-01-01

    Temozolomide (TMZ) is commonly used in glioma chemotherapy. However, a great clinical challenge for TMZ is chemoresistance. H19 transcripts are recognized as long noncoding RNAs, which potentially interact with chromatin-modifying complexes to regulate gene expression via epigenetic changes. Our data based on glioma patients showed that the expression of H19 was significantly upregulated in TMZ-resistant tumors compared with the TMZ-sensitive tumors. To determine the function of H19 in glioma, cell lines U87 and U251 were exposed to TMZ to establish TMZ-resistant clones U87TMZ and U251TMZ. In U87TMZ and U251TMZ, the expression level of H19 transcripts was increased compared to wild-type or nonresistant clones, as determined by real-time quantitative reverse transcription polymerase chain reaction. Concomitant treatment with small interfering RNA specifically targeting H19 and TMZ in resistant glioma clones resulted in decreased IC50 values for TMZ, and increased apoptotic rates than control small interfering RNA-treated cells. This was also evident by the increased PARP cleavage in resistant cells exposed to TMZ + si-H19. Furthermore, the reduced expression of H19 altered major drug resistance genes, such as MDR, MRP, and ABCG2, both at the mRNA and protein levels. Taken together, these findings suggest that H19 plays an important role in the development of TMZ resistance, and may represent a novel therapeutic target for TMZ-resistant gliomas. PMID:27366087

  1. Attenuation of O(6)-methylguanine-DNA methyltransferase activity and mRNA levels by cisplatin and temozolomide in jurkat cells.

    PubMed

    D'Atri, S; Graziani, G; Lacal, P M; Nisticò, V; Gilberti, S; Faraoni, I; Watson, A J; Bonmassar, E; Margison, G P

    2000-08-01

    The DNA repair protein O(6)-methylguanine-DNA methyltransferase (MGMT) is important in cellular resistance to certain alkylating antitumor agents such as the methylating drug temozolomide (TMZ). To provide a more rational basis for clinical combinations with another commonly used drug, cisplatin, we assessed the modulation of MGMT protein and mRNA levels in the human leukemic cell line Jurkat after treatment with these agents. Cisplatin decreased MGMT activity in a time- and dose-dependent manner, with maximal suppression (50%) observed 24 h after treatment with 25 microM cisplatin. This was probably the result of decreased transcription of the MGMT gene, because there was an earlier nadir of MGMT mRNA levels after cisplatin treatment and neither cisplatin nor DNA reacted with cisplatin in vitro was able to inhibit MGMT activity in an in vitro assay. TMZ alone depleted MGMT activity in a time- and dose-dependent manner with almost complete loss of activity occurring immediately after treatment with 500 microM TMZ. Combinations of cisplatin (12.5 microM) and TMZ (250 microM) caused substantial and prolonged MGMT depletion with recovery to only 30% of pretreatment levels by 48 h. These results suggest that the clinical efficacy of TMZ and cisplatin may be improved by appropriate schedules of combinations of these agents.

  2. Downregulation of hPMC2 imparts chemotherapeutic sensitivity to alkylating agents in breast cancer cells

    PubMed Central

    Krishnamurthy, Nirmala; Liu, Lili; Xiong, Xiahui; Zhang, Junran; Montano, Monica M

    2015-01-01

    Triple negative breast cancer cell lines have been reported to be resistant to the cyotoxic effects of temozolomide (TMZ). We have shown previously that a novel protein, human homolog of Xenopus gene which Prevents Mitotic Catastrophe (hPMC2) has a role in the repair of estrogen-induced abasic sites. Our present study provides evidence that downregulation of hPMC2 in MDA-MB-231 and MDA-MB-468 breast cancer cells treated with temozolomide (TMZ) decreases cell survival. This increased sensitivity to TMZ is associated with an increase in number of apurinic/apyrimidinic (AP) sites in the DNA. We also show that treatment with another alkylating agent, BCNU, results in an increase in AP sites and decrease in cell survival. Quantification of western blot analyses and immunofluorescence experiments reveal that treatment of hPMC2 downregulated cells with TMZ results in an increase in γ-H2AX levels, suggesting an increase in double strand DNA breaks. The enhancement of DNA double strand breaks in TMZ treated cells upon downregulation of hPCM2 is also revealed by the comet assay. Overall, we provide evidence that downregulation of hPMC2 in breast cancer cells increases cytotoxicity of alkylating agents, representing a novel mechanism of treatment for breast cancer. Our data thus has important clinical implications in the management of breast cancer and brings forth potentially new therapeutic strategies. PMID:25849309

  3. Therapeutic interactions of autophagy with radiation and temozolomide in glioblastoma: evidence and issues to resolve.

    PubMed

    Koukourakis, Michael I; Mitrakas, Achilleas G; Giatromanolaki, Alexandra

    2016-03-01

    Glioblastoma is a unique model of non-metastasising disease that kills the vast majority of patients through local growth, despite surgery and local irradiation. Glioblastoma cells are resistant to apoptotic stimuli, and their death occurs through autophagy. This review aims to critically present our knowledge regarding the autophagic response of glioblastoma cells to radiation and temozolomide (TMZ) and to delineate eventual research directions to follow, in the quest of improving the curability of this incurable, as yet, disease. Radiation and TMZ interfere with the autophagic machinery, but whether cell response is driven to autophagy flux acceleration or blockage is disputable and may depend on both cell individuality and radiotherapy fractionation or TMZ schedules. Potent agents that block autophagy at an early phase of initiation or at a late phase of autolysosomal fusion are available aside to agents that induce functional autophagy, or even demethylating agents that may unblock the function of autophagy-initiating genes in a subset of tumours. All these create a maze, which if properly investigated can open new insights for the application of novel radio- and chemosensitising policies, exploiting the autophagic pathways that glioblastomas use to escape death. PMID:26889975

  4. Therapeutic interactions of autophagy with radiation and temozolomide in glioblastoma: evidence and issues to resolve

    PubMed Central

    Koukourakis, Michael I; Mitrakas, Achilleas G; Giatromanolaki, Alexandra

    2016-01-01

    Glioblastoma is a unique model of non-metastasising disease that kills the vast majority of patients through local growth, despite surgery and local irradiation. Glioblastoma cells are resistant to apoptotic stimuli, and their death occurs through autophagy. This review aims to critically present our knowledge regarding the autophagic response of glioblastoma cells to radiation and temozolomide (TMZ) and to delineate eventual research directions to follow, in the quest of improving the curability of this incurable, as yet, disease. Radiation and TMZ interfere with the autophagic machinery, but whether cell response is driven to autophagy flux acceleration or blockage is disputable and may depend on both cell individuality and radiotherapy fractionation or TMZ schedules. Potent agents that block autophagy at an early phase of initiation or at a late phase of autolysosomal fusion are available aside to agents that induce functional autophagy, or even demethylating agents that may unblock the function of autophagy-initiating genes in a subset of tumours. All these create a maze, which if properly investigated can open new insights for the application of novel radio- and chemosensitising policies, exploiting the autophagic pathways that glioblastomas use to escape death. PMID:26889975

  5. Radiotherapy plus concomitant temozolomide in primary gliosarcoma.

    PubMed

    Adeberg, Sebastian; Bernhardt, Denise; Harrabi, Semi Ben; Diehl, Christian; Koelsche, Christian; Rieken, Stefan; Unterberg, Andreas; von Deimling, Andreas; Debus, Juergen

    2016-06-01

    Clinical guidelines for gliosarcoma (GSM) are poorly defined and GSM patients are usually treated in accordance with existing guidelines for glioblastoma (GBM), with maximal surgical resection followed by chemoradiation with temozolomide (TMZ). However, it is not clear yet if GSM patients profit from TMZ therapy and if O6-methylguanine-DNA-methyltransferase (MGMT) promoter methylation is crucial. We retrospectively evaluated 37 patients with histologically proven, primary GSM who had received radiation therapy since the temozolomide era (post-2005). Twenty-five patients (67.6 %) received combined chemoradiation with temozolomide, and 12 cases (32.4 %) received radiation therapy alone. Molecular markers were determined retrospectively. Survival and correlations were calculated using log-rank, univariate, and multivariate Cox proportional hazards-ratio analyses. All cases were isocitrate dehydrogenase 1 (IDH1) wildtype, MGMT promoter methylation could be observed in 33.3 % of the assessable cases (10/30) and TERT promoter mutation was seen in a high frequency of 86.7 % (26/30). The influence of TMZ therapy on overall survival (OS) was significantly improved compared with cases in which radiation therapy alone was performed (13.9 vs. 9.9 months; p = 0.045), independently of MGMT promoter methylation. The positive effect of TMZ on OS was confirmed in this study's multivariate analyses (p = 0.04), after adjusting our results for potential confounders. In conclusion, this study demonstrates that concomitant TMZ together with radiation therapy increases GSM-patient survival independent of MGMT promoter methylation. Thus, GSM can be treated in accordance to GBM guidelines. MGMT promoter methylation was infrequent and TERT promoter mutation common without influencing the survival rates. The mechanisms of TMZ effects in GSM are still not fully understood and merit further clinical and molecular-genetic and -biological evaluation. PMID:27025857

  6. NF-κB is activated in response to temozolomide in an AKT-dependent manner and confers protection against the growth suppressive effect of the drug

    PubMed Central

    2012-01-01

    Background Most DNA-damaging chemotherapeutic agents activate the transcription factor nuclear factor κB (NF-κB). However, NF-κB activation can either protect from or contribute to the growth suppressive effects of the agent. We previously showed that the DNA-methylating drug temozolomide (TMZ) activates AKT, a positive modulator of NF-κB, in a mismatch repair (MMR) system-dependent manner. Here we investigated whether NF-κB is activated by TMZ and whether AKT is involved in this molecular event. We also evaluated the functional consequence of inhibiting NF-κB on tumor cell response to TMZ. Methods AKT phosphorylation, NF-κB transcriptional activity, IκB-α degradation, NF-κB2/p52 generation, and RelA and NF-κB2/p52 nuclear translocation were investigated in TMZ-treated MMR-deficient (HCT116, 293TLα-) and/or MMR-proficient (HCT116/3-6, 293TLα+, M10) cells. AKT involvement in TMZ-induced activation of NF-κB was addressed in HCT116/3-6 and M10 cells transiently transfected with AKT1-targeting siRNA or using the isogenic MMR-proficient cell lines pUSE2 and KD12, expressing wild type or kinase-dead mutant AKT1. The effects of inhibiting NF-κB on sensitivity to TMZ were investigated in HCT116/3-6 and M10 cells using the NF-κB inhibitor NEMO-binding domain (NBD) peptide or an anti-RelA siRNA. Results TMZ enhanced NF-κB transcriptional activity, activated AKT, induced IκB-α degradation and RelA nuclear translocation in HCT116/3-6 and M10 but not in HCT116 cells. In M10 cells, TMZ promoted NF-κB2/p52 generation and nuclear translocation and enhanced the secretion of IL-8 and MCP-1. TMZ induced RelA nuclear translocation also in 293TLα+ but not in 293TLα- cells. AKT1 silencing inhibited TMZ-induced IκB-α degradation and NF-κB2/p52 generation. Up-regulation of NF-κB transcriptional activity and nuclear translocation of RelA and NF-κB2/p52 in response to TMZ were impaired in KD12 cells. RelA silencing in HCT116/3-6 and M10 cells increased TMZ

  7. Do Glioma Patients Derive Any Therapeutic Benefit From Taking a Higher Cumulative Dose of Temozolomide Regimens?

    PubMed Central

    Sun, Hao; Du, Shasha; Liao, Guixiang; Xie, Xiao; Ren, Chen; Yuan, Ya Wei

    2015-01-01

    Abstract Temozolomide (TMZ) is an oral alkylating agent with established effects on the central nervous system of glioblastoma (GBM) patients. Clinical trials have demonstrated a significant impact on overall survival (OS) with TMZ. Ever since, several TMZ regimens have been designed to improve treatment efficacy by increasing the cumulative dose per cycle. We report a meta-analysis to systematically evaluate different treatment schedules of TMZ in GBM patients. All searches that were conducted in the Cochrane library, Science Direct, and PubMed Databases, and 3 randomized controlled trials (1141 patients) were included. OS and progression-free survival (PFS) were the primary outcomes to be pooled. Unexpectedly, this analysis did not reveal any OS or PFS advantage for the high cumulative dose (HCD) regimen compared with the normal cumulative dose regimen (1141 total patients; hazard ratio [HR] 1.07, 95% CI 0.94–1.22, P = 0.31). Then after analyzing the characteristics of the results from each trial, we found that the regimen with a higher peak concentration during a short-term period (daily doses ≥150 mg/m2/d within ≤7 days/cycle) always had a more superior clinical benefit. So we generated a new pooled HR of 1.10 with a 95% CI of 0.96–1.25 (P = 0.17), which prefers the high peak concentration schedule even without a significant difference. The adverse outcome also indicates a significant increased risk of leukopenia (risk ratio 1.59, 95% CI 1.03–2.46, P = 0.04) among the HCD group. Our study suggests that increasing the cumulative dose per cycle is not an ideal way to improve the efficacy of TMZ, and it will lead to increased risk for leukopenia. Future trials should be designed to examine schedules of higher peak concentration rather than the cumulative dose per cycle. PMID:25997057

  8. Temozolomide Treatment for Pediatric Refractory Anaplastic Ependymoma with Low MGMT Protein Expression.

    PubMed

    Komori, Kazutoshi; Yanagisawa, Ryu; Miyairi, Yosuke; Sakashita, Kazuo; Shiohara, Masaaki; Fujihara, Ikuko; Morita, Daisuke; Nakamura, Tomohiko; Ogiso, Yoshifumi; Sano, Kenji; Shirahata, Mitsuaki; Fukuoka, Kohei; Ichimura, Koichi; Shigeta, Hiroaki

    2016-01-01

    The benefit of postoperative chemotherapy for anaplastic ependymoma remains unknown. We report two pediatric patients with refractory anaplastic ependymoma treated with temozolomide (TMZ). We did not detect O(6) -methylguanine-DNA methyltransferase (MGMT) promoter methylation in tumor samples; however, MGMT protein expression was low. With TMZ treatment, one patient had a 7-month complete remission; the other, stable disease for 15 months. Three other patients did not respond to TMZ; two had high and one low MGMT expression, and two showed no MGMT promoter methylation. These findings suggest that TMZ may be effective for pediatric refractory anaplastic ependymoma with low MGMT protein expression. PMID:26305586

  9. Combination of anti-VEGF therapy and temozolomide in two experimental human glioma models.

    PubMed

    Grossman, Rachel; Brastianos, Harry; Blakeley, Jaishri O; Mangraviti, Antonella; Lal, Bachchu; Zadnik, Patti; Hwang, Lee; Wicks, Robert T; Goodwin, Rory C; Brem, Henry; Tyler, Betty

    2014-01-01

    Anti-angiogenic agents, such as bevacizumab (BEV), can induce normalization of the blood brain barrier, which may influence the penetration and activity of a co-administered cytotoxic drug. However, it is unknown whether this effect is associated with a benefit in overall survival. This study employed intracranial human glioma models to evaluate the effect of BEV alone and in combination with temozolomide (TMZ) and/or radiation therapy (XRT) on overall survival. One hundred eight male athymic rats were intracranially injected with either U251 or U87 human glioma. Ten or eleven days after tumor inoculation, animals bearing U251 and U87, respectively, were treated with: TMZ alone (50 mg/kg for 5 consecutive days, P.O.), BEV alone (15 mg/kg, I.V.), a combination of TMZ and BEV, or a combination of TMZ, BEV, and a single fraction of XRT (20 Gy). Controls received no treatment. The U87 experiment was repeated and the relationship between survival and the extent of anti-angiogenesis via anti-laminin antibodies for the detection of blood vessels was assessed. In both U87 glioma experiments, all of the treatment groups had a statistically significant increase in survival as compared to the control groups. Also, for both U87 experiments the combination groups of TMZ and BEV had significantly better survival when compared to either treatment administered alone, with 75% of animals demonstrating long-term survival (LTS) (defined as animals alive 120 days after tumor implantation) in one experiment and 25% LTS in the repeat experiment. In the U251 glioma experiment, all treated groups (except BEV alone) had significantly improved survival as compared to controls with minimal statistical variance among groups. The percent vessel area was lowest in the group of animals treated with BEV alone. The addition of BEV to TMZ and/or XRT had variable effect on prolonging survival in the two human glioma models tested with reduced tumor vascularity in groups treated with BEV. These

  10. The synergistic effect of combination temozolomide and chloroquine treatment is dependent on autophagy formation and p53 status in glioma cells.

    PubMed

    Lee, Seung Woo; Kim, Hyun-Kyung; Lee, Na-Hyeon; Yi, Hee-Yeon; Kim, Hong-Sug; Hong, Sung Hee; Hong, Yong-Kil; Joe, Young Ae

    2015-05-01

    Temozolomide (TMZ) is an alkylating agent used for the treatment of glioblastoma. The late autophagy inhibitor chloroquine (CQ) inhibits glioblastoma tumors in a p53-independent and p53-dependent manner. We addressed a possible beneficial effect of combination treatment with TMZ and CQ by examining the molecular and cellular mechanism of co-treatment. Combination treatment of U87 cell (wild type p53) with TMZ and CQ synergistically reduced cell proliferation and enhanced apoptosis, with increased sub-G1 hypodiploid cells and caspase activation. This effect was abolished by a pan-caspase inhibitor, Z-VAD-FMK. TMZ induced autophagy, and the addition of CQ further increased autophagic vacuoles. Inhibition of early stages of autophagy by Beclin 1 knockdown and 3-methyladenine pretreatment prevented the enhanced effect of the combination treatment. The combination treatment also upregulated p53 and phospho-p53 levels, whereas p53 knockdown or overexpression of mutant p53 abolished the combination effect. In contrast, combination therapy had no enhanced effect on U373 cell (mutant p53) proliferation and apoptosis within 3 d, although TMZ induced autophagy and co-treatment with CQ increased autophagic vacuole accumulation. However, long term combination treatment for 9-10 d effectively decreased clonal and cellular growth with increased G2-M arrest. This effect was also abolished by Beclin 1 knockdown. Our data support the beneficial effect of combination treatment with TMZ and CQ in glioma via differential autophagy-associated mechanisms, depending on p53 status. PMID:25681668

  11. Leukemia cells are sensitized to temozolomide, carmustine and melphalan by the inhibition of O6-methylguanine-DNA methyltransferase

    PubMed Central

    ARAI, HAJIME; YAMAUCHI, TAKAHIRO; UZUI, KANAKO; UEDA, TAKANORI

    2015-01-01

    The cytotoxicity of the monofunctional alkylator, temozolomide (TMZ), is known to be mediated by mismatch repair (MMR) triggered by O6-alkylguanine. By contrast, the cytotoxicity of bifunctional alkylators, including carmustine (BCNU) and melphalan (MEL), depends on interstrand crosslinks formed through O6-alkylguanine, which is repaired by nucleotide excision repair and recombination. O6-alkylguanine is removed by O6-methylguanine-DNA methyltransferase (MGMT). The aim of the present study was to evaluate the cytotoxicity of TMZ, BCNU and MEL in two different leukemic cell lines (HL-60 and MOLT-4) in the context of DNA repair. The transcript levels of MGMT, ERCC1, hMLH1 and hMSH2 were determined using reverse transcription-quantitative polymerase chain reaction. In addition, the proliferation was measured using the trypan blue exclusion assay. Drug sensitivity was found to vary between the two cell lines. Treatment of the cells with TMZ, BCNU or MEL in combination with O6-benzylguanine, an MGMT inhibitor, was demonstrated to sensitize the two cell lines to these agents. However, the extent of sensitization was not found to be correlated with the expression levels of MGMT transcripts. Furthermore, the drug sensitivity was also not associated with the transcript levels of ERCC1, hMLH1 and hMSH2. Thus, leukemic cells were sensitized to alkylating agents by the inhibition of MGMT. PMID:26622581

  12. Targeting miR-381-NEFL axis sensitizes glioblastoma cells to temozolomide by regulating stemness factors and multidrug resistance factors

    PubMed Central

    Wang, Zeyou; Yang, Jing; Xu, Gang; Wang, Wei; Liu, Changhong; Yang, Honghui; Yu, Zhibin; Lei, Qianqian; Xiao, Lan; Xiong, Jing; Zeng, Liang; Xiang, Juanjuan; Ma, Jian; Li, Guiyuan; Wu, Minghua

    2015-01-01

    MicroRNA-381 (miR-381) is a highly expressed onco-miRNA that is involved in malignant progression and has been suggested to be a good target for glioblastoma multiforme (GBM) therapy. In this study, we employed two-dimensional fluorescence differential gel electrophoresis (2-D DIGE) and MALDI–TOF/TOF-MS/MS to identify 27 differentially expressed proteins, including the significantly upregulated neurofilament light polypeptide (NEFL), in glioblastoma cells in which miR-381 expression was inhibited. We identified NEFL as a novel target molecule of miR-381 and a tumor suppressor gene. In human astrocytoma clinical specimens, NEFL was downregulated with increased levels of miR-381 expression. Either suppressing miR-381 or enforcing NEFL expression dramatically sensitized glioblastoma cells to temozolomide (TMZ), a promising chemotherapeutic agent for treating GBMs. The mechanism by which these cells were sensitized to TMZ was investigated by inhibiting various multidrug resistance factors (ABCG2, ABCC3, and ABCC5) and stemness factors (ALDH1, CD44, CKIT, KLF4, Nanog, Nestin, and SOX2). Our results further demonstrated that miR-381 overexpression reversed the viability of U251 cells exhibiting NEFL-mediated TMZ sensitivity. In addition, NEFL-siRNA also reversed the proliferation rate of U251 cells exhibiting locked nucleic acid (LNA)-anti-miR-381-mediated TMZ sensitivity. Overall, the miR-381-NEFL axis is important for TMZ resistance in GBM and may potentially serve as a novel therapeutic target for glioma. PMID:25605243

  13. Temozolomide-perillyl alcohol conjugate induced reactive oxygen species accumulation contributes to its cytotoxicity against non-small cell lung cancer.

    PubMed

    Song, Xingguo; Xie, Li; Wang, Xingwu; Zeng, Qian; Chen, Thomas C; Wang, Weijun; Song, Xianrang

    2016-01-01

    Temozolomide-perillyl alcohol conjugate (TMZ - POH), a novel temozolomide analog, was reported to play a cytotoxic role in triple-negative breast cancer and TMZ-resistant gliomas. In a current study we had demonstrated how TMZ - POH also exhibited its cytotoxicity against non-small cell lung cancer (NSCLC), the most common type of lung cancer, as evidence from cell/tumor proliferation inhibition, G2/M arrest, DNA damage and mitochondrial apoptosis. Importantly, TMZ - POH's cytotoxicity is closely related to reactive oxygen species (ROS) accumulation because it can be reversed by two ROS scavengers, catalase (CAT) and N-acetyl-L-cysteine (NAC). TMZ - POH induces mitochondrial transmembrane potential (MTP) decrease and ROS accumulation, in turn activates mitogen-activated protein kinase (MAPKs) signaling and mitochondrial apoptosis, and then exerts its cytotoxicity, thus proposing TMZ - POH as a potential therapeutic candidate for NSCLC. PMID:26949038

  14. Temozolomide Injection

    MedlinePlus

    ... by slowing or stopping the growth of cancer cells in your body. ... during, and after your treatment to check your body's response and to temozolomide to see if your blood cells are affected by this drug.It is important ...

  15. Gliadel wafer implantation combined with standard radiotherapy and concurrent followed by adjuvant temozolomide for treatment of newly diagnosed high-grade glioma: a systematic literature review.

    PubMed

    Ashby, Lynn S; Smith, Kris A; Stea, Baldassarre

    2016-08-24

    Since 2003, only two chemotherapeutic agents, evaluated in phase III trials, have been approved by the US Food and Drug Administration for treatment of newly diagnosed high-grade glioma (HGG): Gliadel wafers (intracranially implanted local chemotherapy) and temozolomide (TMZ) (systemic chemotherapy). Neither agent is curative, but each has been shown to improve median overall survival (OS) compared to radiotherapy (RT) alone. To date, no phase III trial has tested these agents when used in sequential combination; however, a number of smaller trials have reported favorable results. We performed a systematic literature review to evaluate the combination of Gliadel wafers with standard RT (60 Gy) plus concurrent and adjuvant TMZ (RT/TMZ) for newly diagnosed HGG. A literature search was conducted for the period of January 1995 to September 2015. Data were extracted and categorized, and means and ranges were determined. A total of 11 publications met criteria, three prospective trials and eight retrospective studies, representing 411 patients who received Gliadel plus standard RT/TMZ. Patients were similar in age, gender, and performance status. The weighted mean of median OS was 18.2 months (ten trials, n = 379, range 12.7 to 21.3 months), and the weighted mean of median progression-free survival was 9.7 months (seven trials, n = 287, range 7 to 12.9 months). The most commonly reported grade 3 and 4 adverse events were myelosuppression (10.22 %), neurologic deficit (7.8 %), and healing abnormalities (4.3 %). Adverse events reflected the distinct independent safety profiles of Gliadel wafers and RT/TMZ, with little evidence of enhanced toxicity from their use in sequential combination. In the 11 identified trials, an increased benefit from sequentially combining Gliadel wafers with RT/TMZ was strongly suggested. Median OS tended to be improved by 3 to 4 months beyond that observed for Gliadel wafers or TMZ when used alone in the respective phase III

  16. Variant allele frequency enrichment analysis in vitro reveals sonic hedgehog pathway to impede sustained temozolomide response in GBM

    PubMed Central

    Biswas, Nidhan K.; Chandra, Vikas; Sarkar-Roy, Neeta; Das, Tapojyoti; Bhattacharya, Rabindra N.; Tripathy, Laxmi N.; Basu, Sunandan K.; Kumar, Shantanu; Das, Subrata; Chatterjee, Ankita; Mukherjee, Ankur; Basu, Pryiadarshi; Maitra, Arindam; Chattopadhyay, Ansuman; Basu, Analabha; Dhara, Surajit

    2015-01-01

    Neoplastic cells of Glioblastoma multiforme (GBM) may or may not show sustained response to temozolomide (TMZ) chemotherapy. We hypothesize that TMZ chemotherapy response in GBM is predetermined in its neoplastic clones via a specific set of mutations that alter relevant pathways. We describe exome-wide enrichment of variant allele frequencies (VAFs) in neurospheres displaying contrasting phenotypes of sustained versus reversible TMZ-responses in vitro. Enrichment of VAFs was found on genes ST5, RP6KA1 and PRKDC in cells showing sustained TMZ-effect whereas on genes FREM2, AASDH and STK36, in cells showing reversible TMZ-effect. Ingenuity pathway analysis (IPA) revealed that these genes alter cell-cycle, G2/M-checkpoint-regulation and NHEJ pathways in sustained TMZ-effect cells whereas the lysine-II&V/phenylalanine degradation and sonic hedgehog (Hh) pathways in reversible TMZ-effect cells. Next, we validated the likely involvement of the Hh-pathway in TMZ-response on additional GBM neurospheres as well as on GBM patients, by extracting RNA-sequencing-based gene expression data from the TCGA-GBM database. Finally, we demonstrated TMZ-sensitization of a TMZ non-responder neurosphere in vitro by treating them with the FDA-approved pharmacological Hh-pathway inhibitor vismodegib. Altogether, our results indicate that the Hh-pathway impedes sustained TMZ-response in GBM and could be a potential therapeutic target to enhance TMZ-response in this malignancy. PMID:25604826

  17. Bevacizumab and temozolomide versus temozolomide alone as neoadjuvant treatment in unresected glioblastoma: the GENOM 009 randomized phase II trial.

    PubMed

    Balana, Carmen; De Las Penas, Ramon; Sepúlveda, Juan Manuel; Gil-Gil, Miguel J; Luque, Raquel; Gallego, Oscar; Carrato, Cristina; Sanz, Carolina; Reynes, Gaspar; Herrero, Ana; Ramirez, Jose Luis; Pérez-Segura, Pedro; Berrocal, Alfonso; Vieitez, Jose Maria; Garcia, Almudena; Vazquez-Estevez, Sergio; Peralta, Sergi; Fernandez, Isaura; Henriquez, Ivan; Martinez-Garcia, Maria; De la Cruz, Juan Jose; Capellades, Jaume; Giner, Pilar; Villà, Salvador

    2016-05-01

    We sought to determine the impact of bevacizumab on reduction of tumor size prior to chemoradiotherapy in unresected glioblastoma patients. Patients were randomized 1:1 to receive temozolomide (TMZ arm) or temozolomide plus bevacizumab (TMZ + BEV arm). In both arms, neoadjuvant treatment was temozolomide (85 mg/m(2), days 1-21, two 28-day cycles), concurrent radiation plus temozolomide, and six cycles of adjuvant temozolomide. In the TMZ + BEV arm, bevacizumab (10 mg/kg) was added on days 1 and 15 of each neoadjuvant cycle and on days 1, 15 and 30 of concurrent treatment. The primary endpoint was investigator-assessed response to neoadjuvant treatment. Secondary endpoints included progression-free survival (PFS), overall survival (OS), and the impact on outcome of MGMT methylation in tumor and serum. One hundred and two patients were included; 43 in the TMZ arm and 44 in the TMZ + BEV arm were evaluable for response. Results favored the TMZ + BEV arm in terms of objective response (3 [6.7 %] vs. 11 [22.9 %]; odds ratio 4.2; P = 0.04). PFS and OS were longer in the TMZ + BEV arm, though the difference did not reach statistical significance. MGMT methylation in tumor, but not in serum, was associated with outcome. More patients experienced toxicities in the TMZ + BEV than in the TMZ arm (P = 0.06). The combination of bevacizumab plus temozolomide is more active than temozolomide alone and may well confer benefit in terms of tumor shrinkage in unresected patients albeit at the expense of greater toxicity. PMID:26847813

  18. Efficacy of clinically relevant temozolomide dosing schemes in glioblastoma cancer stem cell lines.

    PubMed

    Beier, Dagmar; Schriefer, Beate; Brawanski, Konstantin; Hau, Peter; Weis, Joachim; Schulz, Jörg B; Beier, Christoph P

    2012-08-01

    The effectiveness of temozolomide (TMZ) dosing schemes and the "rechallenge" of recurrent glioblastoma (GBM) with TMZ are controversial. We therefore compared the efficacy of different TMZ dosing schemes against GBM cancer stem cell (CSC) lines in vitro. In O(6)-methyl-guanidine-methyl-transferase (MGMT)-negative CSC lines, all schedules (1 day on/27 days off, 5 days on/23 days off, 7 days on/7 days off, 21 days on/7 days off, continuous low-dose TMZ) depleted clonogenic cells. In TMZ-resistant CSC lines, the 7 days on/7 days off scheme showed higher toxicity as compared with the other schemes. However, clinically feasible concentrations remained ineffective in highly resistant CSC lines. In addition, none of the schedules induced long-term depletion of clonogenic cells even at the highest concentrations (up to 250 μM). After sublethal TMZ treatment for 5 days, TMZ rechallenge of recovering CSC lines remained effective. Our data advocate CSC lines as in vitro model to address clinical questions. Using this model, our data suggest the effectiveness of TMZ in MGMT-negative CSC lines and support the concept of TMZ rechallenge. The 7 days on/7 days off scheme consistently showed the best activity of all schedules in TMZ-resistant CSC lines.

  19. Fluoxetine synergizes with temozolomide to induce the CHOP-dependent endoplasmic reticulum stress-related apoptosis pathway in glioma cells.

    PubMed

    Ma, Jian; Yang, Yan-Ru; Chen, Wei; Chen, Mei-Hua; Wang, Hao; Wang, Xiao-Dan; Sun, Li-Li; Wang, Feng-Ze; Wang, De-Cai

    2016-08-01

    Although temozolomide (TMZ) is the most effective chemotherapy agent for glioma, chemotherapy resistance has limited its clinical use. Fluoxetine (FLT), which is widely used in cancer-related depression, has exhibited potent anticancer properties in different cancer cell types. The aim of this study was i) to evaluate the antitumor mechanism of FLT, and ii) to further evaluate the effects of a combination of FLT and TMZ on glioma cells. Glioma cell lines were exposed to FLT and/or TMZ. Cell viability and apoptosis were examined by CCK-8 assay, flow cytometry and caspase-3 activity assay, respectively. The expression of endoplasmic reticulum-stress (ERS) apoptosis-related proteins was measured using real-time PCR and western blotting. Synergism between the two drugs was evaluated by the combination index (CI) through CompuSyn software. FLT significantly and dose-dependently inhibited the proliferation of various glioma cell lines, and rat glioma C6 cells had a highly sensitive response to the addition of FLT. FLT treatment increased the early apoptosis rate, induced typical apoptotic morphology in the C6 cells and activated caspase-3 with no change in the mitochondrial membrane potential. Further study showed that FLT activated the ERS marker, CHOP. This induction was associated with activation of the PERK-eIF2α-ATF4 and ATF6 cascade. Concomitantly, GADD34, a downstream molecule of CHOP, was also increased. Combined FLT and TMZ treatment showed a synergistic cytotoxic effect in the C6 glioma cells. Knockdown of CHOP expression abolished the synergistic effect of FLT and TMZ in the C6 cells, which suggests that FLT may sensitize glioma cells to TMZ through activation of the CHOP-dependent apoptosis pathway. These results revealed that FLT induced glioma cell apoptosis and sensitized glioma cells to TMZ through activation of the CHOP‑dependent apoptosis pathway. The present study provides a primary basis for using the combination of these drugs in patients with

  20. Fluoxetine synergizes with temozolomide to induce the CHOP-dependent endoplasmic reticulum stress-related apoptosis pathway in glioma cells.

    PubMed

    Ma, Jian; Yang, Yan-Ru; Chen, Wei; Chen, Mei-Hua; Wang, Hao; Wang, Xiao-Dan; Sun, Li-Li; Wang, Feng-Ze; Wang, De-Cai

    2016-08-01

    Although temozolomide (TMZ) is the most effective chemotherapy agent for glioma, chemotherapy resistance has limited its clinical use. Fluoxetine (FLT), which is widely used in cancer-related depression, has exhibited potent anticancer properties in different cancer cell types. The aim of this study was i) to evaluate the antitumor mechanism of FLT, and ii) to further evaluate the effects of a combination of FLT and TMZ on glioma cells. Glioma cell lines were exposed to FLT and/or TMZ. Cell viability and apoptosis were examined by CCK-8 assay, flow cytometry and caspase-3 activity assay, respectively. The expression of endoplasmic reticulum-stress (ERS) apoptosis-related proteins was measured using real-time PCR and western blotting. Synergism between the two drugs was evaluated by the combination index (CI) through CompuSyn software. FLT significantly and dose-dependently inhibited the proliferation of various glioma cell lines, and rat glioma C6 cells had a highly sensitive response to the addition of FLT. FLT treatment increased the early apoptosis rate, induced typical apoptotic morphology in the C6 cells and activated caspase-3 with no change in the mitochondrial membrane potential. Further study showed that FLT activated the ERS marker, CHOP. This induction was associated with activation of the PERK-eIF2α-ATF4 and ATF6 cascade. Concomitantly, GADD34, a downstream molecule of CHOP, was also increased. Combined FLT and TMZ treatment showed a synergistic cytotoxic effect in the C6 glioma cells. Knockdown of CHOP expression abolished the synergistic effect of FLT and TMZ in the C6 cells, which suggests that FLT may sensitize glioma cells to TMZ through activation of the CHOP-dependent apoptosis pathway. These results revealed that FLT induced glioma cell apoptosis and sensitized glioma cells to TMZ through activation of the CHOP‑dependent apoptosis pathway. The present study provides a primary basis for using the combination of these drugs in patients with

  1. Fluoxetine synergizes with temozolomide to induce the CHOP-dependent endoplasmic reticulum stress-related apoptosis pathway in glioma cells

    PubMed Central

    Ma, Jian; Yang, Yan-Ru; Chen, Wei; Chen, Mei-Hua; Wang, Hao; Wang, Xiao-Dan; Sun, Li-Li; Wang, Feng-Ze; Wang, De-Cai

    2016-01-01

    Although temozolomide (TMZ) is the most effective chemotherapy agent for glioma, chemotherapy resistance has limited its clinical use. Fluoxetine (FLT), which is widely used in cancer-related depression, has exhibited potent anticancer properties in different cancer cell types. The aim of this study was i) to evaluate the antitumor mechanism of FLT, and ii) to further evaluate the effects of a combination of FLT and TMZ on glioma cells. Glioma cell lines were exposed to FLT and/or TMZ. Cell viability and apoptosis were examined by CCK-8 assay, flow cytometry and caspase-3 activity assay, respectively. The expression of endoplasmic reticulum-stress (ERS) apoptosis-related proteins was measured using real-time PCR and western blotting. Synergism between the two drugs was evaluated by the combination index (CI) through CompuSyn software. FLT significantly and dose-dependently inhibited the proliferation of various glioma cell lines, and rat glioma C6 cells had a highly sensitive response to the addition of FLT. FLT treatment increased the early apoptosis rate, induced typical apoptotic morphology in the C6 cells and activated caspase-3 with no change in the mitochondrial membrane potential. Further study showed that FLT activated the ERS marker, CHOP. This induction was associated with activation of the PERK-eIF2α-ATF4 and ATF6 cascade. Concomitantly, GADD34, a downstream molecule of CHOP, was also increased. Combined FLT and TMZ treatment showed a synergistic cytotoxic effect in the C6 glioma cells. Knockdown of CHOP expression abolished the synergistic effect of FLT and TMZ in the C6 cells, which suggests that FLT may sensitize glioma cells to TMZ through activation of the CHOP-dependent apoptosis pathway. These results revealed that FLT induced glioma cell apoptosis and sensitized glioma cells to TMZ through activation of the CHOP-dependent apoptosis pathway. The present study provides a primary basis for using the combination of these drugs in patients with

  2. Double-salting out assisted liquid-liquid extraction (SALLE) HPLC method for estimation of temozolomide from biological samples.

    PubMed

    Jain, Darshana; Athawale, Rajani; Bajaj, Amrita; Shrikhande, Shruti

    2014-11-01

    The role of temozolomide (TMZ) in treatment of high grade gliomas, melanomas and other malignancies is being defined by the current clinical developmental trials. Temozolomide belongs to the group of alkylating agents and is prescribed to patients suffering from most aggressive forms of brain tumors. The estimation techniques for temozolomide from the extracted plasma or biological samples includes high-performance liquid chromatography with UV detection (HPLC-UV), micellar electrokinetic capillary chromatography (MKEC) and liquid chromatography coupled to mass spectroscopy (LC-MS). These methods suffer from disadvantages like low resolution, low sensitivity, low recovery or cost involvement. An analytical method possessing capacity to estimate low quantities of TMZ in plasma samples with high extraction efficiency (%) and high resolution with cost effectiveness needs to be developed. Cost effective, robust and low plasma component interfering HPLC method using salting out liquid-liquid extraction (SALLE) technique was developed and validated for estimation of drug from plasma samples. The extraction efficiency (%) with conventional LLE technique with methanol, ethyl acetate, dichloromethane and acetonitrile was found to be 5.99±2.45, 45.39±4.56, 46.04±1.14 and 46.23±3.67 respectively. Extraction efficiency (%) improved with SALLE where sodium chloride was used as an electrolyte and was found to be 6.80±5.56, 52.01±3.13, 62.69±2.11 and 69.20±1.18 with methanol, ethyl acetate, dichloromethane and acetonitrile as organic solvent. Upon utilization of two salts for extraction (double salting liquid-liquid extraction) the extraction efficiency (%) was further improved and was twice of LLE. It was found that double salting liquid-liquid extraction technique yielded extraction efficiency (%) of 11.71±5.66, 55.62±3.44, 77.28±2.89 and 87.75±0.89. Hence a method based on double SALLE was developed for quantification of TMZ demonstrating linearity in the range of

  3. BC3EE2,9B, a synthetic carbazole derivative, upregulates autophagy and synergistically sensitizes human GBM8901 glioblastoma cells to temozolomide.

    PubMed

    Chen, Chien-Min; Syu, Jhih-Pu; Way, Tzong-Der; Huang, Li-Jiau; Kuo, Sheng-Chu; Lin, Chung-Tien; Lin, Chih-Li

    2015-11-01

    Glioblastoma multiforme (GBM) is the most fatal form of human brain cancer. Although temozolomide (TMZ), an oral alkylating chemotherapeutic agent, improves the survival rate, the prognosis of patients with GBM remains poor. Naturally occurring carbazole alkaloids isolated from curry leaves (Murraya koenigii Spreng.) have been shown to possess a wide range of anticancer properties. However, the effects of carbazole derivatives on glioblastoma cells remain poorly understood. In the present study, anti‑glioblastoma profiles of a series of synthetic carbazole derivatives were evaluated in vitro. The most promising derivative in this series was BC3EE2,9B, which showed significant anti‑proliferative effects in GBM8401 and GBM8901 cells. BC3EE2,9B also triggered cell‑cycle arrest, most prominently at the G1 stage, and suppressed glioblastoma cell invasion and migration. Furthermore, BC3EE2,9B induced autophagy‑mediated cell death and synergistically sensitized GBM cells to TMZ cytotoxicity. The possible mechanism underlying BC3EE2,9B‑induced autophagy may involve activation of adenosine monophosphate-activated protein kinase and the attenuation of the Akt and mammalian target of the rapamycin downstream signaling pathway. Taken together, the present results provide molecular evidence for the mode of action governing the ability of BC3EE2,9B to sensitize drug‑resistant glioblastoma cells to the chemotherapeutic agent TMZ.

  4. BC3EE2,9B, a synthetic carbazole derivative, upregulates autophagy and synergistically sensitizes human GBM8901 glioblastoma cells to temozolomide

    PubMed Central

    CHEN, CHIEN-MIN; SYU, JHIH-PU; WAY, TZONG-DER; HUANG, LI-JIAU; KUO, SHENG-CHU; LIN, CHUNG-TIEN; LIN, CHIH-LI

    2015-01-01

    Glioblastoma multiforme (GBM) is the most fatal form of human brain cancer. Although temozolomide (TMZ), an oral alkylating chemotherapeutic agent, improves the survival rate, the prognosis of patients with GBM remains poor. Naturally occurring carbazole alkaloids isolated from curry leaves (Murraya koenigii Spreng.) have been shown to possess a wide range of anticancer properties. However, the effects of carbazole derivatives on glioblastoma cells remain poorly understood. In the present study, anti-glioblastoma profiles of a series of synthetic carbazole derivatives were evaluated in vitro. The most promising derivative in this series was BC3EE2,9B, which showed significant anti-proliferative effects in GBM8401 and GBM8901 cells. BC3EE2,9B also triggered cell-cycle arrest, most prominently at the G1 stage, and suppressed glioblastoma cell invasion and migration. Furthermore, BC3EE2,9B induced autophagy-mediated cell death and synergistically sensitized GBM cells to TMZ cytotoxicity. The possible mechanism underlying BC3EE2,9B-induced autophagy may involve activation of adenosine monophosphate-activated protein kinase and the attenuation of the Akt and mammalian target of the rapamycin downstream signaling pathway. Taken together, the present results provide molecular evidence for the mode of action governing the ability of BC3EE2,9B to sensitize drug-resistant glioblastoma cells to the chemotherapeutic agent TMZ. PMID:26329365

  5. Pine (Pinus morrisonicola Hayata) needle extracts sensitize GBM8901 human glioblastoma cells to temozolomide by downregulating autophagy and O(6)-methylguanine-DNA methyltransferase expression.

    PubMed

    Liao, Chia-Leng; Chen, Chien-Min; Chang, Yan-Zin; Liu, Guang-Yaw; Hung, Hui-Chih; Hsieh, Tung-Ying; Lin, Chih-Li

    2014-10-29

    Pine needle extracts of Pinus morrisonicola (Hayata) are commonly used as a functional health beverage. However, it remains unclear what the mechanism is underlying the antitumor activity of pine needle extract. The aims of present study were to investigate the anti-glioblastoma effects of pine needle extracts as well as its bioactive compounds. From three different solvent extracts of pine needles, the water extract displayed the strongest cytotoxicity effects on GBM8901 glioblastoma cells. The isolated compounds were identified as pinocembrin, chrysin, and tiliroside. Chrysin was the most active ingredient of pine needle extract for the induction of apoptosis and suppression of migration and invasion. It also markedly inhibited temozolomide (TMZ)-induced autophagy and O(6)-methylguanine-DNA methyltransferase (MGMT) expression. Because both autophagy and MGMT overexpression have been implicated to TMZ-induced drug resistance in glioblastoma, our results showed that pine needle extract and chrysin may serve as a potential anticancer agent against glioblastoma, especially with regard to sensitizing glioblastoma cells resistant to TMZ.

  6. Sulforaphane reverses chemo-resistance to temozolomide in glioblastoma cells by NF-κB-dependent pathway downregulating MGMT expression.

    PubMed

    Lan, Fengming; Yang, Yang; Han, Jing; Wu, Qiaoli; Yu, Huiming; Yue, Xiao

    2016-02-01

    The survival benefits of patients with glioblastoma (GBM) remain unsatisfactory due to the intrinsic or acquired resistance to temozolomide (TMZ). We elucidated the mechanisms of sulforaphane (SFN) reverse TMZ resistance in TMZ-inducing cell lines by inhibiting nuclear factor-κB (NF-κB) transcriptional activity. TMZ-resistant cell lines (U87-R and U373-R) were generated by stepwise (6 months) exposure of parental cells to TMZ. Luciferase reporter assay, biochemical assays and subcutaneous tumor establishment were used to characterize the antitumor effect of SFN. MGMT expression and 50% inhibiting concentration (IC50) values of TMZ in GBM cell lines were assessed. Next, we established that U87-R and U373-R cells presenting high IC50 of TMZ, activated NF-κB transcription and significantly increased MGMT expression compared with untreated cells. Furthermore, we revealed that SFN could significantly suppress proliferation of TMZ-resistant GBM cells. In addition, SFN effectively inhibited activity of NF-κB signaling pathway and then reduced MGMT expression to reverse the chemo-resistance to TMZ in T98G, U87-R and U373-R cell lines. Sequential combination with TMZ synergistically inhibited survival capability and increased the induction of apoptosis in TMZ-resistant GBM cells. Finally, a nude mouse model was established with U373-R cell subcutaneous tumor-bearing mice, and results showed that SFN could remarkably suppress cell growth and enhance cell death in chemo-resistant xenografts in the nude mouse model. Collectively, the present study suggests that the clinical efficacy of TMZ-based chemotherapy in TMZ-resistant GBM may be improved by combination with SFN. PMID:26648123

  7. Suppression of the Eag1 potassium channel sensitizes glioblastoma cells to injury caused by temozolomide

    PubMed Central

    Sales, Thais Torquato; Resende, Fernando Francisco Borges; Chaves, Natália Lemos; Titze-De-Almeida, Simoneide Souza; Báo, Sônia Nair; Brettas, Marcella Lemos; Titze-De-Almeida, Ricardo

    2016-01-01

    Glioblastoma multiforme (GBM) is the most aggressive type of human primary brain tumor. The standard treatment protocol includes radiotherapy in combination with temozolomide (TMZ). Despite advances in GBM treatment, the survival time of patients diagnosed with glioma is 14.5 months. Regarding tumor biology, various types of cancer cell overexpress the ether à go-go 1 (Eag1) potassium channel. Therefore, the present study examined the role of Eag1 in the cell damage caused by TMZ on the U87MG glioblastoma cell line. Eag1 was inhibited using a channel blocker (astemizole) or silenced by a short-hairpin RNA expression vector (pKv10.1-3). pKv10.1-3 (0.2 µg) improved the Eag1 silencing caused by 250 µM TMZ, as determined by reverse transcription-quantitative polymerase chain reaction and immunocytochemistry. Additionally, inhibiting Eag1 with the vector or astemizole (5 µM) reduced glioblastoma cell viability and sensitized cells to TMZ. Cell viability decreased by 63% for pKv10.1-3 + TMZ compared with 34% for TMZ alone, and by 77% for astemizole + TMZ compared with 46% for TMZ alone, as determined by MTT assay. In addition, both the vector and astemizole increased the apoptosis rate of glioblastoma cells triggered by TMZ, as determined by an Annexin V apoptosis assay. Collectively, the current data reveal that Eag1 has a role in the damage caused to glioblastoma by TMZ. Furthermore, suppression of this channel can improve the action of TMZ on U87MG glioblastoma cells. Thus, silencing Eag1 is a promising strategy to improve GBM treatment and merits additional studies in animal models of glioma. PMID:27698831

  8. Suppression of the Eag1 potassium channel sensitizes glioblastoma cells to injury caused by temozolomide

    PubMed Central

    Sales, Thais Torquato; Resende, Fernando Francisco Borges; Chaves, Natália Lemos; Titze-De-Almeida, Simoneide Souza; Báo, Sônia Nair; Brettas, Marcella Lemos; Titze-De-Almeida, Ricardo

    2016-01-01

    Glioblastoma multiforme (GBM) is the most aggressive type of human primary brain tumor. The standard treatment protocol includes radiotherapy in combination with temozolomide (TMZ). Despite advances in GBM treatment, the survival time of patients diagnosed with glioma is 14.5 months. Regarding tumor biology, various types of cancer cell overexpress the ether à go-go 1 (Eag1) potassium channel. Therefore, the present study examined the role of Eag1 in the cell damage caused by TMZ on the U87MG glioblastoma cell line. Eag1 was inhibited using a channel blocker (astemizole) or silenced by a short-hairpin RNA expression vector (pKv10.1-3). pKv10.1-3 (0.2 µg) improved the Eag1 silencing caused by 250 µM TMZ, as determined by reverse transcription-quantitative polymerase chain reaction and immunocytochemistry. Additionally, inhibiting Eag1 with the vector or astemizole (5 µM) reduced glioblastoma cell viability and sensitized cells to TMZ. Cell viability decreased by 63% for pKv10.1-3 + TMZ compared with 34% for TMZ alone, and by 77% for astemizole + TMZ compared with 46% for TMZ alone, as determined by MTT assay. In addition, both the vector and astemizole increased the apoptosis rate of glioblastoma cells triggered by TMZ, as determined by an Annexin V apoptosis assay. Collectively, the current data reveal that Eag1 has a role in the damage caused to glioblastoma by TMZ. Furthermore, suppression of this channel can improve the action of TMZ on U87MG glioblastoma cells. Thus, silencing Eag1 is a promising strategy to improve GBM treatment and merits additional studies in animal models of glioma.

  9. Which elderly newly diagnosed glioblastoma patients can benefit from radiotherapy and temozolomide? A PERNO prospective study.

    PubMed

    Franceschi, Enrico; Depenni, Roberta; Paccapelo, Alexandro; Ermani, Mario; Faedi, Marina; Sturiale, Carmelo; Michiara, Maria; Servadei, Franco; Pavesi, Giacomo; Urbini, Benedetta; Pisanello, Anna; Crisi, Girolamo; Cavallo, Michele A; Dazzi, Claudio; Biasini, Claudia; Bertolini, Federica; Mucciarini, Claudia; Pasini, Giuseppe; Baruzzi, Agostino; Brandes, Alba A

    2016-05-01

    The role of temozolomide concurrent with and adjuvant to radiotherapy (RT/TMZ) in elderly patients with glioblastoma (GBM) remains unclear. We evaluated the outcome of patients >70 years in the context of the Project of Emilia-Romagna Region in Neuro-Oncology (PERNO), the first Italian prospective observational population-based study in neuro-oncology. For this analysis the criteria for selecting patients enrolled in the PERNO study were: age >70 years; PS 0-3; histologically confirmed GBM; postoperative radiotherapy (RT) after surgery with or without concomitant temozolomide (TMZ) or postsurgical TMZ alone. Between January 2009 and December 2010, 76 GBM elderly patients were identified in the prospective PERNO study. Twenty-three patients did not receive any treatment after surgery, and 53 patients received postsurgical treatments (25 patients received RT alone and 28 patients RT/TMZ). Median survival was 11.1 months (95 % CI 8.8-13.5), adding temozolomide concomitant and adjuvant to radiotherapy it was 11.6 months (95 % CI 8.6-14.6), and 9.3 months (95 % CI 8.1-10.6) in patients treated with RT alone (P = 0.164). However, patients with MGMT methylated treated with RT/TMZ obtained a better survival (17.2 months, 95 % CI 11.5-22.9) (P = 0.042). No difference in terms of survival were observed if patients with MGMT unmethylated tumor received RT alone, or RT/TMZ or, in MGMT methylated tumor, if patients received radiotherapy alone. In elderly patients RT/TMZ represent a widely used approach but it is effective with methylated MGMT tumors only. PMID:26943851

  10. Which elderly newly diagnosed glioblastoma patients can benefit from radiotherapy and temozolomide? A PERNO prospective study.

    PubMed

    Franceschi, Enrico; Depenni, Roberta; Paccapelo, Alexandro; Ermani, Mario; Faedi, Marina; Sturiale, Carmelo; Michiara, Maria; Servadei, Franco; Pavesi, Giacomo; Urbini, Benedetta; Pisanello, Anna; Crisi, Girolamo; Cavallo, Michele A; Dazzi, Claudio; Biasini, Claudia; Bertolini, Federica; Mucciarini, Claudia; Pasini, Giuseppe; Baruzzi, Agostino; Brandes, Alba A

    2016-05-01

    The role of temozolomide concurrent with and adjuvant to radiotherapy (RT/TMZ) in elderly patients with glioblastoma (GBM) remains unclear. We evaluated the outcome of patients >70 years in the context of the Project of Emilia-Romagna Region in Neuro-Oncology (PERNO), the first Italian prospective observational population-based study in neuro-oncology. For this analysis the criteria for selecting patients enrolled in the PERNO study were: age >70 years; PS 0-3; histologically confirmed GBM; postoperative radiotherapy (RT) after surgery with or without concomitant temozolomide (TMZ) or postsurgical TMZ alone. Between January 2009 and December 2010, 76 GBM elderly patients were identified in the prospective PERNO study. Twenty-three patients did not receive any treatment after surgery, and 53 patients received postsurgical treatments (25 patients received RT alone and 28 patients RT/TMZ). Median survival was 11.1 months (95 % CI 8.8-13.5), adding temozolomide concomitant and adjuvant to radiotherapy it was 11.6 months (95 % CI 8.6-14.6), and 9.3 months (95 % CI 8.1-10.6) in patients treated with RT alone (P = 0.164). However, patients with MGMT methylated treated with RT/TMZ obtained a better survival (17.2 months, 95 % CI 11.5-22.9) (P = 0.042). No difference in terms of survival were observed if patients with MGMT unmethylated tumor received RT alone, or RT/TMZ or, in MGMT methylated tumor, if patients received radiotherapy alone. In elderly patients RT/TMZ represent a widely used approach but it is effective with methylated MGMT tumors only.

  11. Expression of dynein, cytoplasmic 2, heavy chain 1 (DHC2) associated with glioblastoma cell resistance to temozolomide

    PubMed Central

    Wang, Hai; Feng, Wenfeng; Lu, Yuntao; Li, Hezhen; Xiang, Wei; Chen, Ziyang; He, Minyi; Zhao, Liang; Sun, Xuegang; Lei, Bingxi; Qi, Songtao; Liu, Yawei

    2016-01-01

    Temozolomide (TMZ) is the main chemotherapeutic drug utilized for the treatment of glioblastoma multiforme (GMB), however, drug resistance often leads to tumor recurrence and poor outcomes. GMB cell lines were treated with TMZ for up to two weeks and then subjected to proteomics analysis to identify the underlying molecular pathology that is associated with TMZ resistance. Proteomics data showed that TMZ altered expression of proteins that related to cytoskeleton structure and function, such as DHC2 and KIF2B. qRT-PCR and immunofluorescence were used to verify expression of DHC2 and KIF2B in these cells. Immunohistochemistry was used to verify expression of these two proteins in xenografts of a nude mouse model, and ex vivo GBM tissue samples. Their expression was knocked down using siRNA to confirm their role in the regulation of GBM cell sensitivity to TMZ. Knockdown of DHC2 expression enhanced sensitivity of U87 cells to TMZ treatment. Ex vivo data showed that DHC2 expression in GBM tissue samples was associated with tumor recurrence after TMZ chemotherapy. These results indicated cytoskeleton related protein DHC2 reduced sensitivity of GBM cells to TMZ treatment. Further studies should assess DHC2 as a novel target in GBM for TMZ combination treatment. PMID:27375225

  12. Expression of dynein, cytoplasmic 2, heavy chain 1 (DHC2) associated with glioblastoma cell resistance to temozolomide.

    PubMed

    Wang, Hai; Feng, Wenfeng; Lu, Yuntao; Li, Hezhen; Xiang, Wei; Chen, Ziyang; He, Minyi; Zhao, Liang; Sun, Xuegang; Lei, Bingxi; Qi, Songtao; Liu, Yawei

    2016-01-01

    Temozolomide (TMZ) is the main chemotherapeutic drug utilized for the treatment of glioblastoma multiforme (GMB), however, drug resistance often leads to tumor recurrence and poor outcomes. GMB cell lines were treated with TMZ for up to two weeks and then subjected to proteomics analysis to identify the underlying molecular pathology that is associated with TMZ resistance. Proteomics data showed that TMZ altered expression of proteins that related to cytoskeleton structure and function, such as DHC2 and KIF2B. qRT-PCR and immunofluorescence were used to verify expression of DHC2 and KIF2B in these cells. Immunohistochemistry was used to verify expression of these two proteins in xenografts of a nude mouse model, and ex vivo GBM tissue samples. Their expression was knocked down using siRNA to confirm their role in the regulation of GBM cell sensitivity to TMZ. Knockdown of DHC2 expression enhanced sensitivity of U87 cells to TMZ treatment. Ex vivo data showed that DHC2 expression in GBM tissue samples was associated with tumor recurrence after TMZ chemotherapy. These results indicated cytoskeleton related protein DHC2 reduced sensitivity of GBM cells to TMZ treatment. Further studies should assess DHC2 as a novel target in GBM for TMZ combination treatment.

  13. Minor changes in expression of the mismatch repair protein MSH2 exert a major impact on glioblastoma response to temozolomide

    PubMed Central

    McFaline-Figueroa, José L.; Braun, Christian J.; Stanciu, Monica; Nagel, Zachary D.; Mazzucato, Patrizia; Sangaraju, Dewakar; Cerniauskas, Edvinas; Barford, Kelly; Vargas, Amanda; Chen, Yimin; Tretyakova, Natalia; Lees, Jacqueline A.; Hemann, Michael T.; White, Forest M.; Samson, Leona D.

    2015-01-01

    Glioblastoma (GBM) is often treated with the cytotoxic drug temozolomide (TMZ) but the disease inevitably recurs in a drug-resistant form after initial treatment. Here we report that in GBM cells even a modest decrease in the mismatch repair (MMR) components MSH2 and MSH6 have profound effects on TMZ sensitivity. RNAi-mediated attenuation of MSH2 and MSH6 showed that such modest decreases provided an unexpectedly strong mechanism of TMZ resistance. In a mouse xenograft model of human GBM, small changes in MSH2 were sufficient to suppress TMZ-induced tumor regression. Using the Cancer Genome Atlas to analyze mRNA expression patterns in tumors from TMZ-treated GBM patients, we found that MSH2 transcripts in primary GBM could predict patient responses to initial TMZ therapy. In recurrent disease, the absence of microsatellite instability (the standard marker for MMR deficiency) suggests a lack of involvement of MMR in the resistant phenotype of recurrent disease. However, more recent studies reveal that decreased MMR protein levels occur often in recurrent GBM. In accordance with our findings, these reported decreases may constitute a mechanism by which GBM evades TMZ sensitivity while maintaining microsatellite stability. Overall, our results highlight the powerful effects of MSH2 attenuation as a potent mediator of TMZ resistance, and argue that MMR activity offers a predictive marker for initial therapeutic response to TMZ treatment. PMID:26025730

  14. Six-month progression-free survival as an alternative primary efficacy endpoint to overall survival in newly diagnosed glioblastoma patients receiving temozolomide

    PubMed Central

    Polley, Mei-Yin C.; Lamborn, Kathleen R.; Chang, Susan M.; Butowski, Nicholas; Clarke, Jennifer L.; Prados, Michael

    2010-01-01

    We assessed six-month progression-free survival (PFS) as an alternative primary efficacy endpoint to overall survival in newly diagnosed glioblastoma multiforme (GBM) patients receiving temozolomide (TMZ). A total of 183 patients with newly diagnosed GBM enrolled in 3 phase II protocols at the University of California–San Francisco were included. Patients were treated with interventions based on the Stupp regimen, each with the added component of a second oral agent given concurrently with radiotherapy and TMZ, followed by its coadministration with adjuvant TMZ. We examined whether progression status at 2, 4, and 6 months predicted subsequent survival using the landmark analysis. The hazard ratios of death as a function of progression status were estimated based on the Cox proportional hazards model after adjustment for putative prognostic factors. Progression status at 2, 4, and 6 months were all consistently found to be strong predictors of subsequent survival in all studies. The study-specific hazard ratios associated with progression status at 6 months ranged from 2.03 to 3.39. The hazard ratios associated with the earlier time points (2- and 4-month progression) all exceeded 2 in magnitude, ranging from 2.29 to 4.73. P-values were statistically significant for all time points. In this report, we demonstrated a strong association between the endpoints of PFS at 2, 4, and 6 months and survival. Patients who showed the signs of early progression were at significantly higher risk of earlier death. Our analysis suggests that 6-month PFS may be an appropriate primary endpoint in the context of phase II upfront GBM trials in the TMZ era. PMID:20167815

  15. Differential Radiosensitizing Potential of Temozolomide in MGMT Promoter Methylated Glioblastoma Multiforme Cell Lines

    SciTech Connect

    Nifterik, Krista A. van; Berg, Jaap van den; Stalpers, Lukas J.A.; Lafleur, M. Vincent M.; Leenstra, Sieger; Slotman, Ben J.; Hulsebos, Theo J.M.; Sminia, Peter

    2007-11-15

    Purpose: To investigate the radiosensitizing potential of temozolomide (TMZ) for human glioblastoma multiforme (GBM) cell lines using single-dose and fractionated {gamma}-irradiation. Methods and Materials: Three genetically characterized human GBM cell lines (AMC-3046, VU-109, and VU-122) were exposed to various single (0-6 Gy) and daily fractionated doses (2 Gy per fraction) of {gamma}-irradiation. Repeated TMZ doses were given before and concurrent with irradiation treatment. Immediately plated clonogenic cell-survival curves were determined for both the single-dose and the fractionated irradiation experiments. To establish the net effect of clonogenic cell survival and cell proliferation, growth curves were determined, expressed as the number of surviving cells. Results: All three cell lines showed MGMT promoter methylation, lacked MGMT protein expression, and were sensitive to TMZ. The isotoxic TMZ concentrations used were in a clinically feasible range of 10 {mu}mol/L (AMC-3046), 3 {mu}mol/L (VU-109), and 2.5 {mu}mol/L (VU-122). Temozolomide was able to radiosensitize two cell lines (AMC 3046 and VU-122) using single-dose irradiation. A reduction in the number of surviving cells after treatment with the combination of TMZ and fractionated irradiation was seen in all three cell lines, but only AMC 3046 showed a radiosensitizing effect. Conclusions: This study on TMZ-sensitive GBM cell lines shows that TMZ can act as a radiosensitizer and is at least additive to {gamma}-irradiation. Enhancement of the radiation response by TMZ seems to be independent of the epigenetically silenced MGMT gen000.

  16. Pulsed Versus Conventional Radiation Therapy in Combination With Temozolomide in a Murine Orthotopic Model of Glioblastoma Multiforme

    SciTech Connect

    Lee, David Y.; Chunta, John L.; Park, Sean S.; Huang, Jiayi; Martinez, Alvaro A.; Grills, Inga S.; Krueger, Sarah A.; Wilson, George D.; Marples, Brian

    2013-08-01

    Purpose: To evaluate the efficacy of pulsed low-dose radiation therapy (PLRT) combined with temozolomide (TMZ) as a novel treatment approach for radioresistant glioblastoma multiforme (GBM) in a murine model. Methods and Materials: Orthotopic U87MG hGBM tumors were established in Nu-Foxn1{sup nu} mice and imaged weekly using a small-animal micropositron emission tomography (PET)/computed tomography (CT) system. Tumor volume was determined from contrast-enhanced microCT images and tumor metabolic activity (SUVmax) from the F18-FDG microPET scan. Tumors were irradiated 7 to 10 days after implantation with a total dose of 14 Gy in 7 consecutive days. The daily treatment was given as a single continuous 2-Gy dose (RT) or 10 pulses of 0.2 Gy using an interpulse interval of 3 minutes (PLRT). TMZ (10 mg/kg) was given daily by oral gavage 1 hour before RT. Tumor vascularity and normal brain damage were assessed by immunohistochemistry. Results: Radiation therapy with TMZ resulted in a significant 3- to 4-week tumor growth delay compared with controls, with PLRT+TMZ the most effective. PLRT+TMZ resulted in a larger decline in SUVmax than RT+TMZ. Significant differences in survival were evident. Treatment after PLRT+TMZ was associated with increased vascularization compared with RT+TMZ. Significantly fewer degenerating neurons were seen in normal brain after PLRT+TMZ compared with RT+TMZ. Conclusions: PLRT+TMZ produced superior tumor growth delay and less normal brain damage when compared with RT+TMZ. The differential effect of PLRT on vascularization may confirm new treatment avenues for GBM.

  17. Radiosensitizing Effects of Temozolomide Observed in vivo only in a Subset of O6-Methylguanine-DNA Methyltransferase Methylated Glioblastoma Multiforme Xenografts

    SciTech Connect

    Carlson, Brett L.; Grogan, Patrick T.; Mladek, Ann C.; Schroeder, Mark A.; Kitange, Gaspar J.; Decker, Paul A.; Giannini, Caterina; Wu Wenting; Ballman, Karla A.; James, C. David; Sarkaria, Jann N.

    2009-09-01

    Purpose: Concurrent temozolomide (TMZ) and radiation therapy (RT) followed by adjuvant TMZ is standard treatment for patients with glioblastoma multiforme (GBM), although the relative contribution of concurrent versus adjuvant TMZ is unknown. In this study, the efficacy of TMZ/RT was tested with a panel of 20 primary GBM xenografts. Methods and Materials: Mice with intracranial xenografts were treated with TMZ, RT, TMZ/RT, or placebo. Survival ratio for a given treatment/line was defined as the ratio of median survival for treatment vs. placebo. Results: The median survival ratio was significantly higher for O6-methylguanine-DNA methyltransferase (MGMT) methylated tumors versus unmethylated tumors following treatment with TMZ (median survival ratio, 3.6 vs. 1.5, respectively; p = 0.008) or TMZ/RT (5.7 vs. 2.3, respectively; p = 0.001) but not RT alone (1.7 vs. 1.6; p = 0.47). In an analysis of variance, MGMT methylation status and p53 mutation status were significantly associated with treatment response. When we analyzed the additional survival benefit conferred specifically by combined therapy, only a subset (5 of 11) of MGMT methylated tumors derived substantial additional benefit from combined therapy, while none of the MGMT unmethylated tumors did. Consistent with a true radiosensitizing effect of TMZ, sequential treatment in which RT (week 1) was followed by TMZ (week 2) proved significantly less effective than TMZ followed by RT or concurrent TMZ/RT (survival ratios of 4.0, 9.6 and 12.9, respectively; p < 0.0001). Conclusions: Concurrent treatment with TMZ and RT provides significant survival benefit only in a subset of MGMT methylated tumors and provides superior antitumor activity relative to sequential administration of RT and TMZ.

  18. Efficacy of protracted temozolomide dosing is limited in MGMT unmethylated GBM xenograft models

    PubMed Central

    Cen, Ling; Carlson, Brett L.; Pokorny, Jenny L.; Mladek, Ann C.; Grogan, Patrick T.; Schroeder, Mark A.; Decker, Paul A.; Anderson, S. Keith; Giannini, Caterina; Wu, Wenting; Ballman, Karla V.; Kitange, Gaspar J.; Sarkaria, Jann N.

    2013-01-01

    Background Temozolomide (TMZ) is important chemotherapy for glioblastoma multiforme (GBM), but the optimal dosing schedule is unclear. Methods The efficacies of different clinically relevant dosing regimens were compared in a panel of 7 primary GBM xenografts in an intracranial therapy evaluation model. Results Protracted TMZ therapy (TMZ daily M–F, 3 wk every 4) provided superior survival to a placebo-treated group in 1 of 4 O6-DNA methylguanine-methyltransferase (MGMT) promoter hypermethylated lines (GBM12) and none of the 3 MGMT unmethylated lines, while standard therapy (TMZ daily M–F, 1 wk every 4) provided superior survival to the placebo-treated group in 2 of 3 MGMT unmethylated lines (GBM14 and GBM43) and none of the methylated lines. In comparing GBM12, GBM14, and GBM43 intracranial specimens, both GBM14 and GBM43 mice treated with protracted TMZ had a significant elevation in MGMT levels compared with placebo. Similarly, high MGMT was found in a second model of acquired TMZ resistance in GBM14 flank xenografts, and resistance was reversed in vitro by treatment with the MGMT inhibitor O6-benzylguanine, demonstrating a mechanistic link between MGMT overexpression and TMZ resistance in this line. Additionally, in an analysis of gene expression data, comparison of parental and TMZ-resistant GBM14 demonstrated enrichment of functional ontologies for cell cycle control within the S, G2, and M phases of the cell cycle and DNA damage checkpoints. Conclusions Across the 7 tumor models studied, there was no consistent difference between protracted and standard TMZ regimens. The efficacy of protracted TMZ regimens may be limited in a subset of MGMT unmethylated tumors by induction of MGMT expression. PMID:23479134

  19. p53 Small Molecule Inhibitor Enhances Temozolomide Cytotoxic Activity against Intracranial Glioblastoma Xenografts

    PubMed Central

    Dinca, Eduard B.; Lu, Kan V.; Sarkaria, Jann N.; Pieper, Russell O.; Prados, Michael D.; Haas-Kogan, Daphne A.; VandenBerg, Scott R.; Berger, Mitchel S.; James, C. David

    2010-01-01

    In this study we investigated corresponding precursor and active forms of a p53 small molecule inhibitor for effect on temozolomide (TMZ) anti-tumor activity against glioblastoma (GBM), using both in vitro and in vivo experimental approaches. Results from in vitro cell viability analysis showed that the cytotoxic activity of TMZ was substantially increased when GBMs with wild-type p53 were co-treated with the active form of p53 inhibitor, and this heightened cytotoxic response was accompanied by increased PARP cleavage as well as elevated cellular phospho-H2AX. Analysis of the same series of GBMs, as intracranial xenografts in athymic mice, and administering corresponding p53 inhibitor precursor, that is converted to the active compound in vivo, yielded results consistent with the in vitro analyses: i.e., TMZ + p53 inhibitor precursor co-treatment, of three distinct wild-type p53 GBM xenografts, resulted in significant enhancement of TMZ anti-tumor effect relative to treatment with TMZ alone, as indicated by serial bioluminescence monitoring as well as survival analysis (p < 0.001 for co-treatment survival benefit in each case). Mice receiving intracranial injection with p53 null GBM showed similar survival benefit from TMZ treatment regardless of the presence or absence of p53 inhibitor precursor. In total, our results indicate that the p53 active and precursor inhibitor pair enhance TMZ cytotoxicity in vitro and in vivo, respectively, and do so in a p53-dependent manner. PMID:19074867

  20. Optimizing Glioblastoma Temozolomide Chemotherapy Employing Lentiviral-based Anti-MGMT shRNA Technology

    PubMed Central

    Viel, Thomas; Monfared, Parisa; Schelhaas, Sonja; Fricke, Inga B; Kuhlmann, Michael T; Fraefel, Cornel; Jacobs, Andreas H

    2013-01-01

    Despite treatments combining surgery, radiation-, and chemotherapy, patients affected by glioblastoma (GBM) have a limited prognosis. Addition of temozolomide (TMZ) to radiation therapy is the standard therapy in clinical application, but effectiveness of TMZ is limited by the tumor's overexpression of the DNA repair protein O6-methylguanine-DNA methyltransferase (MGMT). The goal of this study was to use the highly specific and efficient RNA interference (RNAi) pathway to modulate MGMT expression to increase TMZ efficiency in chemotherapy resistant GBM. Using lentiviral-based anti-MGMT small hairpin RNA (shRNA) technology we observed a specific inhibition of the MGMT expression in GBM cell lines as well as in subcutaneous tumors. Tumor growth inhibition was observed following TMZ treatment of xenografts with low MGMT expression in contrast to xenografts with high MGMT expression. Bioluminescence imaging (BLI) measurements indicated that luciferase and shRNA-expressing lentiviruses were able to efficiently transduce the GBM xenografts in vivo. Treatment combining injection of a lentivirus expressing an anti-MGMT shRNA and TMZ induced a reduction of the size of the tumors, in contrast with treatment combining the lentivirus expressing the control shRNA and TMZ. Our data suggest that anti-MGMT shRNA therapy could be used in combination with TMZ chemotherapy in order to improve the treatment of resistant GBM. PMID:23319055

  1. p53 Small-molecule inhibitor enhances temozolomide cytotoxic activity against intracranial glioblastoma xenografts.

    PubMed

    Dinca, Eduard B; Lu, Kan V; Sarkaria, Jann N; Pieper, Russell O; Prados, Michael D; Haas-Kogan, Daphne A; Vandenberg, Scott R; Berger, Mitchel S; James, C David

    2008-12-15

    In this study, we investigated the precursor and active forms of a p53 small-molecule inhibitor for their effects on temozolomide (TMZ) antitumor activity against glioblastoma (GBM), using both in vitro and in vivo experimental approaches. Results from in vitro cell viability analysis showed that the cytotoxic activity of TMZ was substantially increased when p53 wild-type (p53(wt)) GBMs were cotreated with the active form of p53 inhibitor, and this heightened cytotoxic response was accompanied by increased poly(ADP-ribose) polymerase cleavage as well as elevated cellular phospho-H2AX. Analysis of the same series of GBMs, as intracranial xenografts in athymic mice, and administering corresponding p53 inhibitor precursor, which is converted to the active compound in vivo, yielded results consistent with the in vitro analyses: TMZ + p53 inhibitor precursor cotreatment of three distinct p53(wt) GBM xenografts resulted in significant enhancement of TMZ antitumor effect relative to treatment with TMZ alone, as indicated by serial bioluminescence monitoring as well as survival analysis (P < 0.001 for cotreatment survival benefit in each case). Mice receiving intracranial injection with p53(null) GBM showed similar survival benefit from TMZ treatment regardless of the presence or absence of p53 inhibitor precursor. In total, our results indicate that the p53 active and precursor inhibitor pair enhances TMZ cytotoxicity in vitro and in vivo, respectively, and do so in a p53-dependent manner.

  2. A Phase 2 Study of Concurrent Radiation Therapy, Temozolomide, and the Histone Deacetylase Inhibitor Valproic Acid For Patients With Glioblastoma

    PubMed Central

    Krauze, Andra V.; Myrehaug, Sten D.; Chang, Michael G.; Holdford, Diane J.; Smith, Sharon; Shih, Joanna; Tofilon, Philip J.; Fine, Howard A.; Camphausen, Kevin

    2015-01-01

    Purpose Valproic acid (VPA) is an antiepileptic agent with histone deacetylase inhibitor (HDACi) activity shown to sensitize glioblastoma (GBM) cells to radiation in pre-clinical models. We evaluated the addition of VPA to standard radiation therapy (RT) and temozolomide (TMZ) in patients with newly diagnosed GBM. Methods and Materials Thirty-seven patients with newly diagnosed GBM were enrolled between July 2006 and April 2013. Patients received VPA, 25 mg/kg orally, divided into 2 daily doses concurrent with RT and TMZ. The first dose of VPA was given 1 week before the first day of RT at 10 to 15 mg/kg/day and subsequently increased up to 25 mg/kg/day over the week prior to radiation. VPA- and TMZ-related acute toxicities were evaluated using Common Toxicity Criteria version 3.0 (National Cancer Institute Cancer Therapy Evaluation Program) and Cancer Radiation Morbidity Scoring Scheme for toxicity and adverse event reporting (Radiation Therapy Oncology Group/European Organization for Research and Treatment). Results A total of 81% of patients took VPA according to protocol. Median overall survival (OS) was 29.6 months (range: 21–63.8 months), and median progression-free survival (PFS) was 10.5 months (range: 6.8–51.2 months). OS at 6, 12, and 24 months was 97%, 86%, and 56%, respectively. PFS at 6, 12, and 24 months was 70%, 43%, and 38% respectively. The most common grade 3/4 toxicities of VPA in conjunction with RT/TMZ therapy were blood and bone marrow toxicity (32%), neurological toxicity (11%), and metabolic and laboratory toxicity (8%). Younger age and class V recursive partitioning analysis results were significant for both OS and PFS. VPA levels were not correlated with grade 3/4 toxicity levels. Conclusions Addition of VPA to concurrent RT/TMZ in patients with newly diagnosed GBM was well tolerated. Additionally, VPA may result in improved outcomes compared to historical data and merits further study. PMID:26194676

  3. A Phase 2 Study of Concurrent Radiation Therapy, Temozolomide, and the Histone Deacetylase Inhibitor Valproic Acid for Patients With Glioblastoma

    SciTech Connect

    Krauze, Andra V.; Chang, Michael G.; Holdford, Diane J.; Smith, Sharon; Shih, Joanna; Tofilon, Philip J.; Camphausen, Kevin

    2015-08-01

    Purpose: Valproic acid (VPA) is an antiepileptic agent with histone deacetylase inhibitor (HDACi) activity shown to sensitize glioblastoma (GBM) cells to radiation in preclinical models. We evaluated the addition of VPA to standard radiation therapy (RT) plus temozolomide (TMZ) in patients with newly diagnosed GBM. Methods and Materials: Thirty-seven patients with newly diagnosed GBM were enrolled between July 2006 and April 2013. Patients received VPA, 25 mg/kg orally, divided into 2 daily doses concurrent with RT and TMZ. The first dose of VPA was given 1 week before the first day of RT at 10 to 15 mg/kg/day and subsequently increased up to 25 mg/kg/day over the week prior to radiation. VPA- and TMZ-related acute toxicities were evaluated using Common Toxicity Criteria version 3.0 (National Cancer Institute Cancer Therapy Evaluation Program) and Cancer Radiation Morbidity Scoring Scheme for toxicity and adverse event reporting (Radiation Therapy Oncology Group/European Organization for Research and Treatment). Results: A total of 81% of patients took VPA according to protocol. Median overall survival (OS) was 29.6 months (range: 21-63.8 months), and median progression-free survival (PFS) was 10.5 months (range: 6.8-51.2 months). OS at 6, 12, and 24 months was 97%, 86%, and 56%, respectively. PFS at 6, 12, and 24 months was 70%, 43%, and 38% respectively. The most common grade 3/4 toxicities of VPA in conjunction with RT/TMZ therapy were blood and bone marrow toxicity (32%), neurological toxicity (11%), and metabolic and laboratory toxicity (8%). Younger age and class V recursive partitioning analysis (RPA) results were significant for both OS and PFS. VPA levels were not correlated with grade 3 or 4 toxicity levels. Conclusions: Addition of VPA to concurrent RT/TMZ in patients with newly diagnosed GBM was well tolerated. Additionally, VPA may result in improved outcomes compared to historical data and merits further study.

  4. Identification of temozolomide resistance factors in glioblastoma via integrative miRNA/mRNA regulatory network analysis.

    PubMed

    Hiddingh, Lotte; Raktoe, Rajiv S; Jeuken, Judith; Hulleman, Esther; Noske, David P; Kaspers, Gertjan J L; Vandertop, W Peter; Wesseling, Pieter; Wurdinger, Thomas

    2014-01-01

    Drug resistance is a major issue in the treatment of glioblastoma. Almost all glioblastomas are intrinsically resistant to chemotherapeutic temozolomide (TMZ) or develop resistance during treatment. The interaction networks of microRNAs (miRNAs) and mRNAs likely regulate most biological processes and can be employed to better understand complex processes including drug resistance in cancer. In this study, we examined if integrative miRNA/mRNA network analysis using the web-service tool mirConnX could be used to identify drug resistance factors in glioblastoma. We used TMZ-resistant glioblastoma cells and their integrated miRNA/mRNA networks to identify TMZ-sensitizing factors. TMZ resistance was previously induced in glioblastoma cell lines U87, Hs683, and LNZ308. miRNA/mRNA expression profiling of these cells and integration of the profiles using mirConnX resulted in the identification of plant homeodomain (PHD)-like finger 6 (PHF6) as a potential TMZ-sensitizing factor in resistant glioblastoma cells. Analysis of PHF6 expression showed significant upregulation in glioblastoma as compared to normal tissue. Interference with PHF6 expression in three TMZ-resistant subclones significantly enhanced TMZ-induced cell kill in two of these cell lines. Altogether, these results demonstrate that mirConnX is a feasible and useful tool to investigate miRNA/mRNA interactions in TMZ-resistant cells and has potential to identify drug resistance factors in glioblastoma.

  5. Identification of temozolomide resistance factors in glioblastoma via integrative miRNA/mRNA regulatory network analysis

    PubMed Central

    Hiddingh, Lotte; Raktoe, Rajiv S.; Jeuken, Judith; Hulleman, Esther; Noske, David P.; Kaspers, Gertjan J. L.; Vandertop, W. Peter; Wesseling, Pieter; Wurdinger, Thomas

    2014-01-01

    Drug resistance is a major issue in the treatment of glioblastoma. Almost all glioblastomas are intrinsically resistant to chemotherapeutic temozolomide (TMZ) or develop resistance during treatment. The interaction networks of microRNAs (miRNAs) and mRNAs likely regulate most biological processes and can be employed to better understand complex processes including drug resistance in cancer. In this study, we examined if integrative miRNA/mRNA network analysis using the web-service tool mirConnX could be used to identify drug resistance factors in glioblastoma. We used TMZ-resistant glioblastoma cells and their integrated miRNA/mRNA networks to identify TMZ-sensitizing factors. TMZ resistance was previously induced in glioblastoma cell lines U87, Hs683, and LNZ308. miRNA/mRNA expression profiling of these cells and integration of the profiles using mirConnX resulted in the identification of plant homeodomain (PHD)-like finger 6 (PHF6) as a potential TMZ-sensitizing factor in resistant glioblastoma cells. Analysis of PHF6 expression showed significant upregulation in glioblastoma as compared to normal tissue. Interference with PHF6 expression in three TMZ-resistant subclones significantly enhanced TMZ-induced cell kill in two of these cell lines. Altogether, these results demonstrate that mirConnX is a feasible and useful tool to investigate miRNA/mRNA interactions in TMZ-resistant cells and has potential to identify drug resistance factors in glioblastoma. PMID:24919120

  6. Organized Pneumonia Secondary to Increasing Doses of Temozolomide

    PubMed Central

    Consuegra Vanegas, Angélica; Matachana Martínez, María; Cordero Lorenzana, Lourdes; Vidal García, Iria; Montero Martínez, Carmen

    2015-01-01

    Surgery, radiotherapy (RT), and chemotherapy have a role in the control of tumor growth, progression, and recurrence in high-grade gliomas. Temozolomide has been incorporated as the main chemotherapy agent for managing these tumors. Here, we present a case of a patient who developed a severe organizing pneumonia after increasing doses of temozolomide for a high-grade glioma. PMID:26487994

  7. A Phase I Trial of Tipifarnib With Radiation Therapy, With and Without Temozolomide, for Patients With Newly Diagnosed Glioblastoma

    SciTech Connect

    Nghiemphu, Phioanh Leia; Wen, Patrick Y.; Drappatz, Jan; Fink, Karen; Malkin, Mark G.; Lieberman, Frank S.; DeAngelis, Lisa M.; Torres-Trejo, Alejandro; Chang, Susan M.; Abrey, Lauren; Fine, Howard A.; Demopoulos, Alexis; Lassman, Andrew B.; Kesari, Santosh; Prados, Michael D.; Cloughesy, Timothy F.

    2011-12-01

    Purpose: To determine the maximum tolerated dose (MTD) of tipifarnib in combination with conventional radiotherapy for patients with newly diagnosed glioblastoma. The MTD was evaluated in three patient cohorts, stratified based on concurrent use of enzyme-inducing antiepileptic drugs (EIAED) or concurrent treatment with temozolomide (TMZ): Group A: patients not receiving EIAED and not receiving TMZ; Group A-TMZ: patients not receiving EIAED and receiving treatment with TMZ; Group B: any patients receiving EIAED but not TMZ. Patients and Methods: After diagnostic surgery or biopsy, treatment with tipifarnib started 5 to 9 days before initiating radiotherapy, twice daily, in 4-week cycles using discontinuous dosing (21 out of 28 days), until toxicity or progression. For Group A-TMZ, patients also received TMZ daily during radiotherapy and then standard 5/28 days dosing after radiotherapy. Dose-limiting toxicity (DLT) was determined over the first 10 weeks of therapy for all cohorts. Results: Fifty-one patients were enrolled for MTD determination: 10 patients in Group A, 21 patients in Group A-TMZ, and 20 patients in Group B. In the Group A and Group A-TMZ cohorts, patients achieved the intended MTD of 300 mg twice daily (bid) with DLTs including rash and fatigue. For Group B, the MTD was determined as 300 mg bid, half the expected dose. The DLTs included rash and one intracranial hemorrhage. Thirteen of the 20 patients evaluated in Group A-TMZ were alive at 1 year. Conclusion: Tipifarnib is well tolerated at 300 mg bid given discontinuously (21/28 days) in 4-week cycles, concurrently with standard chemo/radiotherapy. A Phase II study should evaluate the efficacy of tipifarnib with radiation and TMZ in patients with newly diagnosed glioblastoma and not receiving EIAED.

  8. A phase I trial of tipifarnib with radiation therapy, with and without temozolomide, for patients with newly diagnosed glioblastoma

    PubMed Central

    Nghiemphu, Phioanh Leia; Wen, Patrick Y.; Lamborn, Kathleen R.; Drappatz, Jan; Robins, H. Ian; Fink, Karen; Malkin, Mark G.; Lieberman, Frank S.; DeAngelis, Lisa M.; Torres-Trejo, Alejandro; Chang, Susan M.; Abrey, Lauren; Fine, Howard A.; Demopoulos, Alexis; Lassman, Andrew B.; Kesari, Santosh; Mehta, Minesh P.; Prados, Michael D.; Cloughesy, Timothy F.

    2010-01-01

    Purpose To determine the maximum tolerated dose (MTD) of tipifarnib in combination with conventional radiotherapy (RT) for patients with newly diagnosed glioblastoma (GBM). MTD was evaluated in three patient cohorts, stratified based on concurrent use of enzyme inducing antiepileptic drugs (EIAED) or concurrent treatment with temozolomide (TMZ): Group A - patients not receiving EIAED and not receiving TMZ; Group A-TMZ - patients not on EIAED, and on treatment with TMZ; Group B – any patients receiving EIAED, but no TMZ. Methods and Materials After diagnostic surgery or biopsy, treatment with tipifarnib started 5–9 days before initiating RT, twice daily, in four-week cycles using discontinuous dosing (21 out of 28 days), until toxicity or progression. For Group A-TMZ, patients also received TMZ daily during radiotherapy and then standard 5/28 days dosing after radiotherapy. Dose limiting toxicity (DLT) was determined over the first 10 weeks of therapy for all cohorts. Results Fifty-one patients were enrolled for MTD determination: 10 patients in Group A, 21 patients in Group A-TMZ, 20 patients in Group B. In Group A and Group A-TMZ cohorts, patients achieved the intended MTD of 300 mg bid with DLTs including rash and fatigue. For Group B, the MTD was determined as 300 mg bid, half the expected dose. DLTs included rash and 1 intracranial hemorrhage. Thirteen of the 20 patients evaluated in Group A-TMZ were alive at one year. Conclusion Tipifarnib is well tolerated at 300 mg bid given discontinuously (21/28 days) in 4-week cycles, concurrently with standard chemo/radiotherapy. A phase II study should evaluate the efficacy of tipifarnib with radiation and TMZ in patients with newly diagnosed GBM and not on EIAED. PMID:20934264

  9. Chemoradiotherapy of Newly Diagnosed Glioblastoma With Intensified Temozolomide

    SciTech Connect

    Weiler, Markus; Hartmann, Christian; Wiewrodt, Dorothee; Herrlinger, Ulrich

    2010-07-01

    Purpose: To evaluate the toxicity and efficacy of chemoradiotherapy with temozolomide (TMZ) administered in an intensified 1-week on/1-week off schedule plus indomethacin in patients with newly diagnosed glioblastoma. Patients and Methods: A total of 41 adult patients (median Karnofsky performance status, 90%; median age, 56 years) were treated with preirradiation TMZ at 150 mg/m{sup 2} (1 week on/1 week off), involved-field radiotherapy combined with concomitant low-dose TMZ (50 mg/m{sup 2}), maintenance TMZ starting at 150 mg/m{sup 2} using a 1-week on/1-week off schedule, plus maintenance indomethacin (25 mg twice daily). Results: The median follow-up interval was 21.7 months. Grade 4 hematologic toxicity was observed in 15 patients (36.6%). Treatment-related nonhematologic Grade 4-5 toxicity was reported for 2 patients (4.9%). The median progression-free survival was 7.6 months (95% confidence interval, 6.2-10.4). The 1-year survival rate was 73.2% (95% confidence interval, 56.8-84.2%). The presence of O{sup 6}-methylguanine-DNA methyltransferase (MGMT) gene promoter methylation in the tumor tissue was associated with significantly superior progression-free survival. Conclusion: The dose-dense regimen of TMZ administered in a 1-week on/1-week off schedule resulted in acceptable nonhematologic toxicity. Compared with data from the European Organization for Research and Treatment of Cancer/National Cancer Institute of Canada trial 26981-22981/CE.3, patients with an unmethylated MGMT gene promoter appeared not to benefit from intensifying the TMZ schedule regarding the median progression-free survival and overall survival. In contrast, data are promising for patients with a methylated MGMT promoter.

  10. Thymoquinone synergistically potentiates temozolomide cytotoxicity through the inhibition of autophagy in U87MG cell line

    PubMed Central

    Pazhouhi, Mona; Sariri, Reyhaneh; Rabzia, Arezou; Khazaei, Mozafar

    2016-01-01

    Objective(s): Glioblastoma multiforme (GBM) is one of the most lethal forms of human cancer and temozolomide (TMZ) is currently part of the standard treatment for this disease. Combination therapy using natural substances can enhance the anti-cancer activity of TMZ. The purpose of this study was to evaluate the effect of TMZ in combination with thymoquinone (TQ) on human GBM cell line (U87MG). Materials and Methods: The cell line was treated with TMZ and/or TQ. Cell viability was assessed using trypan blue and MTT assay. The effect of TMZ and/or TQ on colony-forming ability of the cells was investigated. Apoptosis and autophagy were quantified by fluorescent dye staining. The expression level of two autophagy related genes (ATG) were assessed using RT-PCR. Furthermore, nitric oxide (NO) production was detected by Griess reaction. Results: After treatment with TMZ and/or TQ, the cell viability was reduced in a time- and dose-dependent manner, and the cell survival fraction (SF) was significantly decreased (P=0.000). Apoptosis index of U87MG cells was also significantly increased (P=0.000). Autophagy was significantly increased by TMZ (P=0.000) and decreased by TQ (P=0.018). Also TMZ and/or TQ significantly decreased NO production by U87MG cell (P=0.000). Conclusion: TQ enhanced the anti-cancer activity of TMZ by inhibition of autophagy at the transcriptional level and decreased the colony-forming ability and NO production of U87MG cell line. PMID:27746872

  11. Continuous Low-Dose Temozolomide Chemotherapy and Microvessel Density in Recurrent Glioblastoma

    PubMed Central

    Woo, Jong-Yun; Yang, Seung Ho; Lee, Youn Soo; Lee, Su Youn; Kim, Jeana

    2015-01-01

    Objective The purpose of this study was to evaluate the clinical efficacy of continuous low-dose temozolomide (TMZ) chemotherapy for recurrent and TMZ-refractory glioblastoma multiforme (GBM) and to study the relationship between its efficacy and microvessel density within the tumor. Methods Thirty patients who had recurrent GBM following Stupp's regimen received TMZ daily at 50 mg/m2/day until tumor progression between 2007 and 2013. The median duration of continuous low-dose TMZ administration was 8 weeks (range, 2-64). Results The median progression-free survival (PFS) of continuous low-dose TMZ therapy was 2 months (range, 0.5-16). At 6 months, PFS was 20%. The median overall survival (OS) from the start of this therapy to death was 6 months (95% CI : 5.1-6.9). Microvessel density of recurrent tumor tissues obtained by reoperation of 17 patients was 22.7±24.1/mm2 (mean±standard deviation), and this was lower than that of the initial tumor (61.4±32.7/mm2) (p-value=0.001). It suggests that standard TMZ-chemoradiotherapy reduces the microvessel density within GBM and that recurrences develop in tumor cells with low metabolic burden. The efficacy of continuous low-dose TMZ could not be expected in recurrent GBM cells in poor angiogenic environments. Conclusion The efficacy of continuous low-dose TMZ chemotherapy is marginal. This study suggests the need to develop further treatment strategies for recurrent and TMZ-refractory GBM. PMID:26713142

  12. Glioma-associated endothelial cells are chemoresistant to temozolomide.

    PubMed

    Virrey, Jenilyn J; Golden, Encouse B; Sivakumar, Walavan; Wang, Weijun; Pen, Ligaya; Schönthal, Axel H; Hofman, Florence M; Chen, Thomas C

    2009-10-01

    Temozolomide is considered the standard of care and drug of choice for the treatment of initially diagnosed malignant gliomas. Although well tolerated, temozolomide still has limited clinical efficacy. Following drug treatment, patient prognosis still remains poor; tumor recurrence is almost universal. We hypothesized that this lack of effectiveness with temozolomide is because this drug does not target the glioma microenvironment, which is highly vascular in malignant gliomas. To test this hypothesis we analyzed the effects of temozolomide on the tumor vasculature in vitro and in vivo. We found that this drug did not affect the viability or proliferation rate of endothelial cells isolated from human glioma specimens, although temozolomide was highly cytotoxic to the glioma cell lines U87MG and U251. Furthermore, temozolomide did not inhibit the migration of these glioma-associated endothelial cells, a key mechanism responsible for tumor angiogenesis. In in vivo studies, using the intracranial glioma mouse model, temozolomide did not cause a pronounced effect on microvessel density. Our findings show that temozolomide has no apparent effect on the glioma vascular microenvironment. Thus combination therapy with anti-vascular agents may enhance temozolomide effectiveness as glioma therapeutic protocol.

  13. Tumor stroma and chemokines control T-cell migration into melanoma following Temozolomide treatment

    PubMed Central

    Tan, Kar Wai; Evrard, Maximilien; Tham, Muly; Hong, Michelle; Huang, Caleb; Kato, Masashi; Prevost-Blondel, Armelle; Donnadieu, Emmanuel; Ng, Lai Guan; Abastado, Jean-Pierre

    2015-01-01

    The infiltration of T lymphocytes within tumors is associated with better outcomes in cancer patients, yet current understanding of factors that influence T-lymphocyte infiltration into tumors remains incomplete. In our study, Temozolomide (TMZ), a chemotherapeutic drug used to treat metastatic melanoma, induced T-cell infiltration into transplanted melanoma and into genitourinary (GU) tumors in mice developing spontaneous melanoma. In contrast, TMZ treatment did not increase T-cell infiltration into cutaneous tumors, despite similar increases in the expression of the (C-X-C) chemokines CXCL9 and CXCL10 in all sites after TMZ exposure. Our findings reveal that the matrix architecture of the GU tumor stroma, and its ability to present CXCL9 and CXCL10 after TMZ treatment played a key role in favouring T-cell infiltration. We subsequently demonstrate that modifications of these key elements by combined collagenase and TMZ treatment induced T-cell infiltration into skin tumors. T cells accumulating within GU tumors after TMZ treatment exhibited T helper type-1 effector and cytolytic functional phenotypes, which are important for control of tumor growth. Our findings highlight the importance of the interaction between tumor stroma and chemokines in influencing T-cell migration into tumors, thereby impacting immune control of tumor growth. This knowledge will aid the development of strategies to promote T-cell infiltration into cancerous lesions and has the potential to markedly improve treatment outcomes. PMID:25949877

  14. MiR-16 modulate temozolomide resistance by regulating BCL-2 in human glioma cells

    PubMed Central

    Han, Jing; Chen, Qianxue

    2015-01-01

    Temozolomide (TMZ) with radiotherapy is the current standard of care for newly diagnosed glioma. However, glioma patients who are treated with the drug often develop resistance to it and some other drugs. Recently studies have shown that microRNAs (miRNAs) play an important role in drug resistance. In present study, we first examined the sensitivity to temozolomide in six glioma cell lines, and established a resistant variant, U251MG/TR cells from TMZ-sensitive glioma cell line, U251MG. We then performed a comprehensive analysis of miRNA expressions in U251MG/TR and parental cells using cancer microRNA PCR Array. Among the downregulated microRNAs was miR-16, members of miR-15/16 family, whose expression was further validated by qRT-PCR in U251MG/TR and U251MG cells. The selective microRNA, miR-16 mimics or inhibitor was respectively transfected into U251MG/TR cells and AM38 cell. We found that treatment with the mimics of miR-16 greatly decreased the sensitivity of U251MG/TR cells to temozolomide, while sensitivity to these drugs was increased by treatment with the miR-16 inhibitor. In addition, the downregulation of miR-16 in temozolomide-sensitive AM38 cells was concurrent with the upregulation of Bcl-2 protein. Conversely, overexpression of miR-16 in temozolomide-resistant cells inhibited Bcl-2 expression and decreased temozolomide resistance. In conclusion, MiR-16 mediated temozolomide-resistance in glioma cells by modulation of apoptosis via targeting Bcl-2, which suggesting that miR-16 and Bcl-2 would be potential therapeutic targets for glioma therapy. PMID:26722459

  15. MiR-16 modulate temozolomide resistance by regulating BCL-2 in human glioma cells.

    PubMed

    Han, Jing; Chen, Qianxue

    2015-01-01

    Temozolomide (TMZ) with radiotherapy is the current standard of care for newly diagnosed glioma. However, glioma patients who are treated with the drug often develop resistance to it and some other drugs. Recently studies have shown that microRNAs (miRNAs) play an important role in drug resistance. In present study, we first examined the sensitivity to temozolomide in six glioma cell lines, and established a resistant variant, U251MG/TR cells from TMZ-sensitive glioma cell line, U251MG. We then performed a comprehensive analysis of miRNA expressions in U251MG/TR and parental cells using cancer microRNA PCR Array. Among the downregulated microRNAs was miR-16, members of miR-15/16 family, whose expression was further validated by qRT-PCR in U251MG/TR and U251MG cells. The selective microRNA, miR-16 mimics or inhibitor was respectively transfected into U251MG/TR cells and AM38 cell. We found that treatment with the mimics of miR-16 greatly decreased the sensitivity of U251MG/TR cells to temozolomide, while sensitivity to these drugs was increased by treatment with the miR-16 inhibitor. In addition, the downregulation of miR-16 in temozolomide-sensitive AM38 cells was concurrent with the upregulation of Bcl-2 protein. Conversely, overexpression of miR-16 in temozolomide-resistant cells inhibited Bcl-2 expression and decreased temozolomide resistance. In conclusion, MiR-16 mediated temozolomide-resistance in glioma cells by modulation of apoptosis via targeting Bcl-2, which suggesting that miR-16 and Bcl-2 would be potential therapeutic targets for glioma therapy.

  16. Treatment of glioblastoma multiforme cells with temozolomide-BioShuttle ligated by the inverse Diels-Alder ligation chemistry

    PubMed Central

    Braun, Klaus; Wiessler, Manfred; Ehemann, Volker; Pipkorn, Ruediger; Spring, Herbert; Debus, Juergen; Didinger, Bernd; Koch, Mario; Muller, Gabriele; Waldeck, Waldemar

    2008-01-01

    Recurrent glioblastoma multiforme (GBM), insensitive against most therapeutic interventions, has low response and survival rates. Temozolomide (TMZ) was approved for second-line therapy of recurrent anaplastic astrocytoma. However, TMZ therapy in GBM patients reveals properties such as reduced tolerability and inauspicious hemogram. The solution addressed here concerning GBM therapy consolidates and uses the potential of organic and peptide chemistry with molecular medicine. We enhanced the pharmacologic potency with simultaneous reduction of unwanted adverse reactions of the highly efficient chemotherapeutic TMZ. The TMZ connection to transporter molecules (TMZ-BioShuttle) was investigated, resulting in a much higher pharmacological effect in glioma cell lines and also with reduced dose rate. From this result we can conclude that a suitable chemistry could realize the ligation of pharmacologically active, but sensitive and highly unstable pharmaceutical ingredients without functional deprivation. The TMZ-BioShuttle dramatically enhanced the potential of TMZ for the treatment of brain tumors and is an attractive drug for combination chemotherapy. PMID:19920915

  17. The synergic antitumor effects of paclitaxel and temozolomide co-loaded in mPEG-PLGA nanoparticles on glioblastoma cells

    PubMed Central

    Li, Yiming; Sun, Ying; Teng, Yanwei; Wang, Yi; Duan, Yourong

    2016-01-01

    To get better chemotherapy efficacy, the optimal synergic effect of Paclitaxel (PTX) and Temozolomide (TMZ) on glioblastoma cells lines was investigated. A dual drug-loaded delivery system based on mPEG-PLGA nanoparticles (NPs) was developed to potentiate chemotherapy efficacy for glioblastoma. PTX/TMZ-NPs were prepared with double emulsification solvent evaporation method and exhibited a relatively uniform diameter of 206.3 ± 14.7 nm. The NPs showed sustained release character. Cytotoxicity assays showed the best synergistic effects were achieved when the weight ratios of PTX to TMZ were 1:5 and 1:100 on U87 and C6 cells, respectively. PTX/TMZ-NPs showed better inhibition effect to U87 and C6 cells than single drug NPs or free drugs mixture. PTX/TMZ-NPs (PTX: TMZ was 1:5(w/w)) significantly inhibited the tumor growth in the subcutaneous U87 mice model. These results indicate that coordinate administration of PTX and TMZ combined with NPs is an efficient method for glioblastoma. PMID:26956046

  18. Outcomes of pediatric glioblastoma treated with adjuvant chemoradiation with temozolomide and correlation with prognostic factors

    PubMed Central

    Mallick, Supriya; Gandhi, Ajeet Kumar; Joshi, Nikhil P.; Kumar, Anupam; Puri, Tarun; Sharma, Daya Nand; Haresh, Kunhi Parambath; Gupta, Subhash; Julka, Pramod Kumar; Rath, Goura Kisor; Sarkar, Chitra

    2015-01-01

    Background: Pediatric glioblastoma (pGBM) patients are underrepresented in major trials for this disease. We aimed to explore the outcome of pGBM patients treated with concurrent and adjuvant temozolomide (TMZ). Materials and Methods: 23 patients of pGBM treated from 2004 to 2010 were included in this retrospective analysis. Adjuvant therapy included conformal radiation 60 gray at 2 gray/fraction daily over 6 weeks with concurrent TMZ 75 mg/m2 followed by six cycles of adjuvant TMZ 150-200 mg/m2 (day 1-5) every 4 weeks. Kaplan-Meier estimates of overall survival (OS) were determined. Univariate analysis with log-rank test was used to determine the impact of prognostic variables on survival. Results: Median age at presentation was 11.5 years (range: 7-19 years) and M:F ratio was 15:8. All patients underwent maximal safe surgical resection; 13 gross total resection and 10 sub-total resection. At a median follow-up of 18 months (range: 2.1-126 months), the estimated median OS was 41.9 months. The estimated median OS for patients receiving only concurrent TMZ was 8 months while that for patients receiving concurrent and adjuvant TMZ was 41.9 months (P = 0.081). Estimated median OS for patients who did not complete six cycles of adjuvant TMZ was 9.5 months versus not reached for those who completed at least six cycles (P = 0.0005). Other prognostic factors did not correlate with survival. Conclusions: Our study shows the benefit of TMZ for pGBM patients. Both concurrent and adjuvant TMZ seem to be important for superior OS in this group of patients. PMID:26157286

  19. APE1/REF-1 down-regulation enhances the cytotoxic effects of temozolomide in a resistant glioblastoma cell line.

    PubMed

    Montaldi, Ana P; Godoy, Paulo R D V; Sakamoto-Hojo, Elza T

    2015-11-01

    Temozolomide (TMZ) is widely used for patients with glioblastoma (GBM); however, tumor cells frequently exhibit drug-resistance. Base excision repair (BER) has been identified as a possible mediator of TMZ resistance, and an attractive approach to sensitizing cells to chemotherapy. Human apurinic/apyrimidinic endonuclease/redox factor-1 (APE1) is an essential enzyme with a role in the BER pathway by repairing abasic sites, and it also acts as a reduction factor, maintaining transcription factors in an active reduced state. Thus, we aimed to investigate whether the down-regulation of APE1 expression by siRNA can interfere with the resistance of GBM to TMZ, being evaluated by several cellular and molecular parameters. We demonstrated that APE1 knockdown associated with TMZ treatment efficiently reduced cell proliferation and clonogenic survival of resistant cells (T98G), which appears to be a consequence of increased DNA damage, S-phase arrest, and H2AX phosphorylation, resulting in apoptosis induction. On the contrary, for those assays, the sensitization effects of APE1 silencing plus TMZ treatment did not occur in the TMZ-sensitive cell line (U87MG). Interestingly, TMZ-treatment and APE1 knockdown significantly reduced cell invasion in both cell lines, but TMZ alone did not reduce the invasion capacity of U87MG cells, as observed for T98G. We also found that VEGF expression was down-regulated by TMZ treatment in T98G cells, regardless of APE1 knockdown, but U87MG showed a different response, since APE1 silencing counteracted VEGF induction promoted by TMZ, suggesting that the APE1-redox function may play an indirect role, depending on the cell line. The present results support the contribution of BER in the GBM resistance to TMZ, with a greater effect in TMZ-resistant, compared with TMZ-sensitive cells, emphasizing that APE1 can be a promising target for modifying TMZ tolerance. Furthermore, genetic characteristics of tumor cells should be considered as critical

  20. Temozolomide Therapy for Aggressive Pituitary Tumors: Results in a Small Series of Patients from Argentina

    PubMed Central

    Bruno, Oscar D.; Juárez-Allen, Lea; Christiansen, Silvia B.; Manavela, Marcos; Danilowicz, Karina; Vigovich, Carlos; Gómez, Reynaldo M.

    2015-01-01

    We evaluated results of temozolomide (TMZ) therapy in six patients, aged 34–78 years, presenting aggressive pituitary tumors. In all the patients tested O6-methylguanine-DNA methyltransferase (MGMT) immunoexpression in surgical specimens was absent. Patients received temozolomide 140–320 mg/day for 5 days monthly for at least 3 months. In two patients minimum time for evaluation could not be reached because of death in a 76-year-old man with a malignant prolactinoma and of severe neutro-thrombopenia in a 47-year-old woman with nonfunctioning pituitary adenoma. In two patients (a 34-year-old acromegalic woman and a 39-year-old woman with Nelson's syndrome) no response was observed after 4 and 6 months, respectively, and the treatment was stopped. Conversely, two 52- and 42-year-old women with Cushing's disease had long-term total clinical and radiological remissions which persisted after stopping temozolomide. We conclude that TMZ therapy may be of variable efficacy depending on—until now—incompletely understood factors. Cooperative work on a greater number of cases of aggressive pituitary tumors should be crucial to establish the indications, doses, and duration of temozolomide administration. PMID:26106414

  1. [Evaluation of stability of temozolomide in solutions after opening the capsule].

    PubMed

    Kodawara, Takaaki; Mizuno, Tomoyuki; Taue, Hiromi; Hashida, Tohru; Yano, Ikuko; Katsura, Toshiya; Inui, Ken-Ichi

    2009-03-01

    We evaluated the stability of temozolomide, an alkylating agent, in solutions after opening the capsule. First, we established an analytical method for determination of temozolomide concentration by HPLC. The calibration curve for temozolomide was linear between 0.5-20 microg/ml (r=0.999). We then evaluated the stability of temozolomide in each buffer solution (pH 2-9) for 30 min. Temozolomide was decomposed pH-dependently between pH 7 and 9, and completely decomposed at pH 9. Temozolomide in several drinking water samples and beverages was decomposed according to their pH values. We also examined the time-dependent degradation of temozolomide in different pH solutions. Temozolomide started to decompose at 5 min in alkaline and neutral solutions, whereas 90% of temozolomide remained intact in acidic solution at 60 min. These results indicate that the stability of temozolomide after opening the capsule is affected by pH of solvents, and temozolomide is almost stable in acidic solutions. PMID:19252393

  2. Macitentan, a dual endothelin receptor antagonist, in combination with temozolomide leads to glioblastoma regression and long-term survival in mice

    PubMed Central

    Kim, Sun-Jin; Lee, Ho Jeong; Kim, Mark Seungwook; Choi, Hyun Jin; He, Junqin; Wu, Qiuyu; Aldape, Kenneth; Weinberg, Jeffrey S.; Alfred Yung, W. K.; Conrad, Charles A.; Langley, Robert R.; Lehembre, François; Regenass, Urs; Fidler, Isaiah J.

    2016-01-01

    Purpose The objective of the study was to determine whether astrocytes and brain endothelial cells protect glioma cells from temozolomide (TMZ) through an endothelin-dependent signaling mechanism and to examine the therapeutic efficacy of the dual endothelin receptor antagonist, macitentan, in orthotopic models of human glioblastoma. Experimental Design We evaluated several endothelin receptor antagonists for their ability to inhibit astrocyte- and brain endothelial cell-induced protection of glioma cells from TMZ in chemoprotection assays. We compared survival in nude mice bearing orthotopically implanted LN-229 glioblastomas or TMZ-resistant (LN-229Res and D54Res) glioblastomas that were treated with macitentan, TMZ, or both. Tumor burden was monitored weekly with bioluminescence imaging. The effect of therapy on cell division, apoptosis, tumor-associated vasculature, and pathways associated with cell survival was assessed by immunofluorescent microscopy. Results Only dual endothelin receptor antagonism abolished astrocyte- and brain endothelial cell-mediated protection of glioma cells from TMZ. In five independent survival studies, including TMZ-resistant glioblastomas, 46 of 48 (96%) mice treated with macitentan plus TMZ had no evidence of disease (P<0.0001), whereas all mice in other groups died. In another analysis, macitentan plus TMZ therapy was stopped in 16 mice after other groups had died. Only 3 of 16 mice eventually developed recurrent disease, 2 of which responded to additional cycles of macitentan plus TMZ. Macitentan downregulated proteins associated with cell division and survival in glioma cells and associated endothelial cells, which enhanced their sensitivity to TMZ. Conclusions Macitentan plus TMZ are well tolerated, produce durable responses, and warrant clinical evaluation in glioblastoma patients. PMID:26106074

  3. Retinoblastoma Binding Protein 4 Modulates Temozolomide Sensitivity in Glioblastoma by Regulating DNA Repair Proteins

    PubMed Central

    Kitange, Gaspar J.; Mladek, Ann C.; Schroeder, Mark A.; Pokorny, Jenny C.; Carlson, Brett L.; Zhang, Yuji; Nair, Asha A.; Lee, Jeong-Heon; Yan, Huihuang; Decker, Paul A.; Zhang, Zhiguo; Sarkaria, Jann N.

    2016-01-01

    Summary Here we provide evidence that RBBP4 modulates temozolomide (TMZ) sensitivity through coordinate regulation of 2 key DNA repair genes critical for recovery from TMZ-induced DNA damage: methylguanine-DNA-methyltransferase (MGMT) and RAD51. Disruption of RBBP4 enhanced TMZ sensitivity, induced synthetic lethality to PARP inhibition and increased DNA damage signaling in response to TMZ. Moreover, RBBP4 silencing enhanced TMZ-induced H2AX phosphorylation and apoptosis in GBM cells. Intriguingly, RBBP4 knockdown suppressed the expression of MGMT, RAD51 and other genes in association with decreased promoter H3K9 acetylation (H3K9Ac) and increased H3K9 tri-methylation (H3K9me3). Consistent with these data, RBBP4 interacts with CBP/p300 to form a chromatin modifying complex that binds within the promoter of MGMT, RAD51 and perhaps other genes. Globally, RBBP4 positively and negatively regulates genes involved in critical cellular functions including tumorigenesis. RBBP4/CBP/p300 complex may provide an interesting target for developing therapy sensitizing strategies for GBM and other tumors. PMID:26972001

  4. Polysaccharide-based nanocomplexes for co-encapsulation and controlled release of 5-Fluorouracil and Temozolomide.

    PubMed

    Di Martino, Antonio; Pavelkova, Alena; Maciulyte, Sandra; Budriene, Saulute; Sedlarik, Vladimir

    2016-09-20

    Polysaccharide-based nanocomplexes, intended for simultaneous encapsulation and controlled release of 5-Fluorouracil (5-FU) and Temozolomide (TMZ) were developed via the complexation method using chitosan, alginic and polygalacturonic acid. Investigation focused on the influence of polysaccharides on the properties of the system and amelioration of the stability of the drugs, in particular TMZ. The dimensions of particles and their ζ-potential were found to range between 100 and 200nm and -25 to +40mV, respectively. Encapsulation efficiency varied from 16% to over 70%, depending on the given system. The influence of pH on the release and co-release of TMZ and 5-FU was evaluated under different pH conditions. The stability of the loaded drug, in particular TMZ, after release was evaluated and confirmed by LC-MS analysis. Results suggested that the amount of loaded drug(s) and the release rate is connected with the weight ratio of polysaccharides and the pH of the media. One-way ANOVA analysis on the obtained data revealed no interference between the drugs during the encapsulation and release process, and in particular no hydrolysis of TMZ occurred suggesting that CS-ALG and CS-PGA would represent interesting carriers for multi-drug controlled release and drugs protection.

  5. Synthesis of TiO 2 nanostructured reservoir with temozolomide: Structural evolution of the occluded drug

    NASA Astrophysics Data System (ADS)

    López, T.; Sotelo, J.; Navarrete, J.; Ascencio, J. A.

    2006-10-01

    Sol-gel synthesized nanostructured TiO 2 matrix were produced with different channel sizes, where drug are immersed, producing a reservoir with Temozolomide (TMZ). This drug is particularly important for the treatment of cancer tumors, which are fundamentally a consequence of the uncontrolled reproduction of human cell. In this way the chemotherapy plays an important role in the treatment of both recurrent and newly diagnosed patients. In the handling of brain tumors TMZ has been discovered as a recent and efficient second generation drug employed in the control of advanced brain gliomas, and it is a welcome addition. Its active component binds to the cancerous DNA cells, thus preventing their disordered growth, destroying them. In this work, we report the synthesis of TiO 2 nanostructured reservoir with TMZ, focusing the effort to the understanding of structural effects on the TMZ configuration by using nuclear magnetic resonance, Raman and IR spectroscopy methods. Our results establish that TMZ molecules are quite sensible to chemical processes and it produces the activation of the molecule, which is followed and understood with help of quantum molecular simulation methods. The study of the molecules allows determining the conditions that produce the activation and chemical selectivity of the molecules, which determines the conditions of synthesis. This information gives parameters for the reservoir structural and chemical optimization.

  6. Evaluation of novel imidazotetrazine analogues designed to overcome temozolomide resistance and glioblastoma regrowth.

    PubMed

    Ramirez, Yulian P; Mladek, Ann C; Phillips, Roger M; Gynther, Mikko; Rautio, Jarkko; Ross, Alonzo H; Wheelhouse, Richard T; Sakaria, Jann N

    2015-01-01

    The cellular responses to two new temozolomide (TMZ) analogues, DP68 and DP86, acting against glioblastoma multiforme (GBM) cell lines and primary culture models are reported. Dose-response analysis of cultured GBM cells revealed that DP68 is more potent than DP86 and TMZ and that DP68 was effective even in cell lines resistant to TMZ. On the basis of a serial neurosphere assay, DP68 inhibits repopulation of these cultures at low concentrations. The efficacy of these compounds was independent of MGMT and MMR functions. DP68-induced interstrand DNA cross-links were demonstrated with H2O2-treated cells. Furthermore, DP68 induced a distinct cell-cycle arrest with accumulation of cells in S phase that is not observed for TMZ. Consistent with this biologic response, DP68 induces a strong DNA damage response, including phosphorylation of ATM, Chk1 and Chk2 kinases, KAP1, and histone variant H2AX. Suppression of FANCD2 expression or ATR expression/kinase activity enhanced antiglioblastoma effects of DP68. Initial pharmacokinetic analysis revealed rapid elimination of these drugs from serum. Collectively, these data demonstrate that DP68 is a novel and potent antiglioblastoma compound that circumvents TMZ resistance, likely as a result of its independence from MGMT and mismatch repair and its capacity to cross-link strands of DNA.

  7. Radiotherapy with or without temozolomide in elderly patients aged ≥ 70 years with glioblastoma

    PubMed Central

    Karaoglanoglu, Ozden; Akyazici, Emine

    2016-01-01

    Introduction Although the recommended optimal treatment of glioblastoma multiforme (GBM) is adjuvant chemoradiotherapy, trials in GBM have excluded patients older than 70 years. In this study, we aimed to assess overall survival (OS) and prognostic factors in elderly patients (≥ 70 years) with newly diagnosed GBM treated with radiotherapy (RT) ± concurrent/adjuvant temozolomide (TMZ). Material and methods Inclusion criteria were patients ≥ 70 years, pre-RT Karnofsky performance status (KPS) ≥ 60, and time between diagnosis and start of RT ≤ 2 months. A total of 40 patients aged ≥ 70 years, 12 female and 28 male, treated between January 2004 and December 2012, were evaluated. Median age was 73.5 years (range, 70–83 years). The median RT dose was 60 Gy (range, 30–62 Gy). Twenty-one (52.5%) received concurrent TMZ, and of those 12 (30%) went on to receive adjuvant TMZ. Results The median OS was 7 months (95% CI: 5.45–8.54). One- and two-year OS for the whole cohort was 38% and 16%, respectively. Sex, type of surgery, tumor size, and RT dose did not significantly affect the OS. Presence of concurrent TMZ (p < 0.005) and presence of adjuvant TMZ (p < 0.001) were associated with longer OS in our cohort. Conclusions RT ± TMZ seems to be a well-tolerated treatment in patients ≥ 70 years with GBM. Even though no superiority was found between conventional or hypofractionated RT regimens (p = 0.405), the addition of concurrent and adjuvant TMZ to RT increased the OS in our study.

  8. Radiotherapy with or without temozolomide in elderly patients aged ≥ 70 years with glioblastoma

    PubMed Central

    Karaoglanoglu, Ozden; Akyazici, Emine

    2016-01-01

    Introduction Although the recommended optimal treatment of glioblastoma multiforme (GBM) is adjuvant chemoradiotherapy, trials in GBM have excluded patients older than 70 years. In this study, we aimed to assess overall survival (OS) and prognostic factors in elderly patients (≥ 70 years) with newly diagnosed GBM treated with radiotherapy (RT) ± concurrent/adjuvant temozolomide (TMZ). Material and methods Inclusion criteria were patients ≥ 70 years, pre-RT Karnofsky performance status (KPS) ≥ 60, and time between diagnosis and start of RT ≤ 2 months. A total of 40 patients aged ≥ 70 years, 12 female and 28 male, treated between January 2004 and December 2012, were evaluated. Median age was 73.5 years (range, 70–83 years). The median RT dose was 60 Gy (range, 30–62 Gy). Twenty-one (52.5%) received concurrent TMZ, and of those 12 (30%) went on to receive adjuvant TMZ. Results The median OS was 7 months (95% CI: 5.45–8.54). One- and two-year OS for the whole cohort was 38% and 16%, respectively. Sex, type of surgery, tumor size, and RT dose did not significantly affect the OS. Presence of concurrent TMZ (p < 0.005) and presence of adjuvant TMZ (p < 0.001) were associated with longer OS in our cohort. Conclusions RT ± TMZ seems to be a well-tolerated treatment in patients ≥ 70 years with GBM. Even though no superiority was found between conventional or hypofractionated RT regimens (p = 0.405), the addition of concurrent and adjuvant TMZ to RT increased the OS in our study. PMID:27647990

  9. Temozolomide resistance in glioblastoma occurs by miRNA-9-targeted PTCH1, independent of sonic hedgehog level.

    PubMed

    Munoz, Jessian L; Rodriguez-Cruz, Vivian; Ramkissoon, Shakti H; Ligon, Keith L; Greco, Steven J; Rameshwar, Pranela

    2015-01-20

    Glioblastoma Multiforme (GBM), the most common and lethal adult primary tumor of the brain, showed a link between Sonic Hedgehog (SHH) pathway in the resistance to temozolomide (TMZ). PTCH1, the SHH receptor, can tonically represses signaling by endocytosis. We asked how the decrease in PTCH1 in GBM cells could lead to TMZ-resistance. TMZ resistant GBM cells have increased PTCH1 mRNA and reduced protein. Knockdown of Dicer, a Type III RNAase, indicated that miRNAs can explain the decreased PTCH1 in TMZ resistant cells. Computational studies, real-time PCR, reporter gene studies, western blots, target protector oligos and ectopic expression identified miR-9 as the target of PTCH1 in resistant GBM cells with concomitant activation of SHH signaling. MiR-9 mediated increases in the drug efflux transporters, MDR1 and ABCG2. MiR-9 was increased in the tissues from GBM patients and in an early passage GBM cell line from a patient with recurrent GBM but not from a naïve patient. Pharmacological inhibition of SHH signaling sensitized the GBM cells to TMZ. Taken together, miR-9 targets PTCH1 in GBM cells by a SHH-independent method in GBM cells for TMZ resistance. The identified pathways could lead to new strategies to target GBM with combinations of drugs. PMID:25595896

  10. Hypofractionated Versus Standard Radiation Therapy With or Without Temozolomide for Older Glioblastoma Patients

    SciTech Connect

    Arvold, Nils D.; Aizer, Ayal A.; Chiocca, E. Antonio

    2015-06-01

    Purpose: Older patients with newly diagnosed glioblastoma have poor outcomes, and optimal treatment is controversial. Hypofractionated radiation therapy (HRT) is frequently used but has not been compared to patients receiving standard fractionated radiation therapy (SRT) and temozolomide (TMZ). Methods and Materials: We conducted a retrospective analysis of patients ≥65 years of age who received radiation for the treatment of newly diagnosed glioblastoma from 1994 to 2013. The distribution of clinical covariates across various radiation regimens was analyzed for possible selection bias. Survival was calculated using the Kaplan-Meier method. Comparison of hypofractionated radiation (typically, 40 Gy/15 fractions) versus standard fractionation (typically, 60 Gy/30 fractions) in the setting of temozolomide was conducted using Cox regression and propensity score analysis. Results: Patients received SRT + TMZ (n=57), SRT (n=35), HRT + TMZ (n=34), or HRT (n=9). Patients receiving HRT were significantly older (median: 79 vs 69 years of age; P<.001) and had worse baseline performance status (P<.001) than those receiving SRT. On multivariate analysis, older age (adjusted hazard ratio [AHR]: 1.06; 95% confidence interval [CI]: 1.01-1.10, P=.01), lower Karnofsky performance status (AHR: 1.02; 95% CI: 1.01-1.03; P=.01), multifocal disease (AHR: 2.11; 95% CI: 1.23-3.61, P=.007), and radiation alone (vs SRT + TMZ; SRT: AHR: 1.72; 95% CI: 1.06-2.79; P=.03; HRT: AHR: 3.92; 95% CI: 1.44-10.60, P=.007) were associated with decreased overall survival. After propensity score adjustment, patients receiving HRT with TMZ had similar overall survival compared with those receiving SRT with TMZ (AHR: 1.10, 95% CI: 0.50-2.4, P=.82). Conclusions: With no randomized data demonstrating equivalence between HRT and SRT in the setting of TMZ for glioblastoma, significant selection bias exists in the implementation of HRT. Controlling for this bias, we observed similar overall

  11. In Vitro Responsiveness of Glioma Cell Lines to Multimodality Treatment With Radiotherapy, Temozolomide, and Epidermal Growth Factor Receptor Inhibition With Cetuximab

    SciTech Connect

    Combs, Stephanie E. . E-mail: Stephanie.Combs@med.uni-heidelberg.de; Schulz-Ertner, Daniela; Roth, Wilfried; Herold-Mende, Christel; Debus, Juergen; Weber, Klaus-Josef

    2007-07-01

    Background: The majority of glioblastoma multiforme (GBM) cells express the epidermal growth factor receptor (EGFR). The present study evaluates the combination of temozolomide (TMZ), EGFR inhibition, and radiotherapy (RT) in GBM cell lines. Methods and Materials: Human GBM cell lines U87, LN229, LN18, NCH 82, and NCH 89 were treated with various combinations of TMZ, RT, and the monoclonal EGFR antibody cetuximab. Responsiveness of glioma cells to the combination treatment was measured by clonogenic survival. Results: Overall, double and triple combinations of RT, TMZ, and cetuximab lead to additive cytotoxic effects (independent toxicity). A notable exception was observed for U87 and LN 18 cell lines, where the combination of TMZ and cetuximab showed substantial antagonism. Interestingly, in these two cell lines, the combination of RT with cetuximab resulted in a substantial increase in cell killing over that expected for independent toxicity. The triple combination with RT, cetuximab, and TMZ was nearly able to overcome the antagonism for the TMZ/cetuximab combination in U87, however only marginally in LN18, GBM cell lines. Conclusion: It appears that EGFR expression is not correlated with cytotoxic effects exerted by cetuximab. Combination treatment with TMZ, cetuximab and radiation resulted in independent toxicity in three out of five cell lines evaluated, the antagonistic effect of the TMZ/cetuximab combination in two cell lines could indicate that TMZ preferentially kills cetuximab-resistant cells, suggesting for some cross-talk between toxicity mechanisms. Expression of EGFR was no surrogate marker for responsiveness to cetuximab, alone or in combination with RT and TMZ.

  12. Phase I study of iniparib concurrent with monthly or continuous temozolomide dosing schedules in patients with newly diagnosed malignant gliomas.

    PubMed

    Blakeley, Jaishri O; Grossman, Stuart A; Mikkelsen, Tom; Rosenfeld, Myrna R; Peereboom, David; Nabors, L Burt; Chi, Andrew S; Emmons, Gary; Garcia Ribas, Ignacio; Supko, Jeffrey G; Desideri, Serena; Ye, Xiaobu

    2015-10-01

    Iniparib is a prodrug that converts to highly reactive cytotoxic metabolites intracellularly with activity in preclinical glioma models. We investigated the maximum tolerated dose (MTD) of iniparib with monthly (m) and continuous (c) temozolomide (TMZ) dosing schedules in patients with malignant gliomas (MG). Adults with newly diagnosed MG who had successfully completed ≥80% of radiation (RT) and TMZ without toxicity received mTMZ dosing (150-200 mg/m(2) days 1-5/28 days) or cTMZ dosing (75 mg/m(2)/days × 6 weeks) in conjunction with iniparib (i.v. 2 days/week) in the adjuvant setting. Iniparib was dose escalated using a modified continual reassessment method (mCRM). 43 patients (32 male; 34 GBM, 8 AA, 1 gliosarcoma; median age 54 years; median KPS 90) were enrolled across 4 dose levels. In the mTMZ group, 2/4 patients had dose limiting toxicities (DLT) at 19 mg/kg/week (rash/hypersensitivity). At 17.2 mg/kg/week, 1/9 patients had a DLT (grade 3 fatigue). Additional grade 3 toxicities were neutropenia, lymphopenia, and nausea. In the cTMZ group, one DLT (thromboembolic event) occurred at 10.2 mg/kg/week. Dose escalation stopped at 16 mg/kg/week based on mCRM. The mean maximum plasma concentration of iniparib increased with dose. Concentration of the two major circulating metabolites, 4-iodo-3-aminobenzamide and 4-iodo-3-aminobenzoic acid, was ≤5% of the corresponding iniparib concentration. Iniparib is well tolerated, at doses higher than previously investigated, in combination with TMZ after completion of RT + TMZ in patients with MG. Recommended phase 2 dosing of iniparib based on mCRM is 17.2 mg/kg/week with mTMZ and 16 mg/kg/week with cTMZ. An efficacy study of TMZ/RT + iniparib followed by TMZ + iniparib in newly diagnosed GBM using these doses has completed enrollment. Survival assessment is ongoing. PMID:26285766

  13. Phase I study of iniparib concurrent with monthly or continuous temozolomide dosing schedules in patients with newly diagnosed malignant gliomas

    PubMed Central

    Blakeley, Jaishri O.; Grossman, Stuart A.; Mikkelsen, Tom; Rosenfeld, Myrna R.; Peereboom, David; Nabors, L. Burt; Chi, Andrew S.; Emmons, Gary; Ribas, Ignacio Garcia; Supko, Jeffrey G.; Desideri, Serena; Ye, Xiaobu

    2016-01-01

    Background Iniparib is a prodrug that converts to highly reactive cytotoxic metabolites intracellularly with activity in preclinical glioma models. We investigated the maximum tolerated dose (MTD) of iniparib with monthly (m) and continuous (c) temozolomide (TMZ) dosing schedules in patients with malignant gliomas (MG). Methods Adults with newly diagnosed MG who had successfully completed ≥ 80% of radiation (RT) and TMZ without toxicity received mTMZ dosing (150-200 mg/m2 days 1-5/28 days) or cTMZ dosing (75 mg/m2/d × 6weeks) in conjunction with iniparib (i.v. 2 days/wk) in the adjuvant setting. Iniparib was dose escalated using a modified continual reassessment method (mCRM). Results 43 patients (32 male; 34 GBM, 8 AA, 1 gliosarcoma; median age 54 yrs; median KPS 90) were enrolled across 4 dose levels. In the mTMZ group, 2/4 patients had dose limiting toxicities (DLT) at 19mg/kg/week (rash/hypersensitivity). At 17.2mg/kg/week, 1/9 patients had a DLT (grade 3 fatigue). Additional grade 3 toxicities were neutropenia, lymphopenia, and nausea. In the cTMZ group, one DLT (thromboembolic event) occurred at 10.2mg/kg/wk. Dose escalation stopped at 16mg/kg/week based on mCRM. The mean maximum plasma concentration of iniparib increased with dose. Concentration of the two major circulating metabolites, 4-iodo-3-aminobenzamide and 4-iodo-3-aminobenzoic acid, was ≤ 5% of the corresponding iniparib concentration. Conclusions Iniparib is well tolerated, at doses higher than previously investigated, in combination with TMZ after completion of RT + TMZ in patients with MG. Recommended phase 2 dosing of iniparib based on mCRM is 17.2mg/kg/wk with mTMZ and 16mg/kg/wk with cTMZ. An efficacy study of TMZ/RT + iniparib followed by TMZ + iniparib in newly diagnosed GBM using these doses has completed enrollment. Survival assessment is ongoing. PMID:26285766

  14. Silencing erythropoietin receptor on glioma cells reinforces efficacy of temozolomide and X-rays through senescence and mitotic catastrophe.

    PubMed

    Pérès, Elodie A; Gérault, Aurélie N; Valable, Samuel; Roussel, Simon; Toutain, Jérôme; Divoux, Didier; Guillamo, Jean-Sébastien; Sanson, Marc; Bernaudin, Myriam; Petit, Edwige

    2015-02-10

    Hypoxia-inducible genes may contribute to therapy resistance in glioblastoma (GBM), the most aggressive and hypoxic brain tumours. It has been recently reported that erythropoietin (EPO) and its receptor (EPOR) are involved in glioma growth. We now investigated whether EPOR signalling may modulate the efficacy of the GBM current treatment based on chemotherapy (temozolomide, TMZ) and radiotherapy (X-rays). Using RNA interference, we showed on glioma cell lines (U87 and U251) that EPOR silencing induces a G2/M cell cycle arrest, consistent with the slowdown of glioma growth induced by EPOR knock-down. In vivo, we also reported that EPOR silencing combined with TMZ treatment is more efficient to delay tumour recurrence and to prolong animal survival compared to TMZ alone. In vitro, we showed that EPOR silencing not only increases the sensitivity of glioma cells to TMZ as well as X-rays but also counteracts the hypoxia-induced chemo- and radioresistance. Silencing EPOR on glioma cells exposed to conventional treatments enhances senescence and induces a robust genomic instability that leads to caspase-dependent mitotic death by increasing the number of polyploid cells and cyclin B1 expression. Overall these data suggest that EPOR could be an attractive target to overcome therapeutic resistance toward ionising radiation or temozolomide.

  15. Mismatch repair deficiency: a temozolomide resistance factor in medulloblastoma cell lines that is uncommon in primary medulloblastoma tumours

    PubMed Central

    von Bueren, A O; Bacolod, M D; Hagel, C; Heinimann, K; Fedier, A; Kordes, U; Pietsch, T; Koster, J; Grotzer, M A; Friedman, H S; Marra, G; Kool, M; Rutkowski, S

    2012-01-01

    Background: Tumours are responsive to temozolomide (TMZ) if they are deficient in O6-methylguanine-DNA methyltransferase (MGMT), and mismatch repair (MMR) proficient. Methods: The effect of TMZ on medulloblastoma (MB) cell killing was analysed with clonogenic survival assays. Expression of DNA repair genes and enzymes was investigated using microarrays, western blot, and immunohistochemistry. DNA sequencing and promoter methylation analysis were employed to investigate the cause of loss of the expression of MMR gene MLH1. Results: Temozolomide exhibited potent cytotoxic activity in D425Med (MGMT deficient, MLH1 proficient; IC50=1.7 μℳ), moderate activity against D341Med (MGMT proficient, MLH1 deficient), and DAOY MB cells (MGMT proficient, MLH1 proficient). MGMT inhibitor O6-benzylguanine sensitised DAOY, but not D341Med cells to TMZ. Of 12 MB cell lines, D341Med, D283Med, and 1580WÜ cells exhibited MMR deficiency due to MLH1 promoter hypermethylation. DNA sequencing of these cells provided no evidence for somatic genetic alterations in MLH1. Expression analyses of MMR and MGMT in MB revealed that all patient specimens (n=74; expression array, n=61; immunostaining, n=13) are most likely MMR proficient, whereas some tumours had low MGMT expression levels (according to expression array) or were totally MGMT deficient (3 out of 13 according to immunohistochemistry). Conclusion: A subset of MB may respond to TMZ as some patient specimens are MGMT deficient, and tumours appear to be MMR proficient. PMID:22976800

  16. Prospective Evaluation of Radiotherapy With Concurrent and Adjuvant Temozolomide in Children With Newly Diagnosed Diffuse Intrinsic Pontine Glioma

    SciTech Connect

    Jalali, Rakesh; Raut, Nirmal; Arora, Brijesh; Gupta, Tejpal; Dutta, Debnarayan; Munshi, Anusheel; Sarin, Rajiv; Kurkure, Purna

    2010-05-01

    Purpose: To present outcome data in a prospective study of radiotherapy (RT) with concurrent and adjuvant temozolomide (TMZ) in children with diffuse intrinsic pontine gliomas (DIPGs). Methods and Materials: Pediatric patients with newly diagnosed DIPGs were prospectively treated with focal RT to a dose of 54 Gy in 30 fractions along with concurrent daily TMZ (75 mg/m{sup 2}, Days 1-42). Four weeks after completing the initial RT-TMZ schedule, adjuvant TMZ (200 mg/m{sup 2}, Days 1-5) was given every 28 days to a maximum of 12 cycles. Response was evaluated clinically and radiologically with magnetic resonance imaging and positron emission tomography scans. Results: Between March 2005 and November 2006, 20 children (mean age, 8.3 years) were accrued. Eighteen patients have died from disease progression, one patient is alive with progressive disease, and one patient is alive with stable disease. Median overall survival and progression-free survival were 9.15 months and 6.9 months, respectively. Grade III/IV toxicity during the concurrent RT-TMZ phase included thrombocytopenia in 3 patients, leucopenia in 2, and vomiting in 7. Transient Grade II skin toxicity developed in the irradiated fields in 18 patients. During the adjuvant TMZ phase, Grade III/IV leucopenia developed in 2 patients and Grade IV thrombocytopenia in 1 patient. Patients with magnetic resonance imaging diagnosis of a high-grade tumor had worse survival than those with a low-grade tumor (p = 0.001). Patients with neurologic improvement after RT-TMZ had significantly better survival than those who did not (p = 0.048). Conclusions: TMZ with RT has not yielded any improvement in the outcome of DIPG compared with RT alone. Further clinical trials should explore novel treatment modalities.

  17. Effect of the STAT3 inhibitor STX-0119 on the proliferation of a temozolomide-resistant glioblastoma cell line.

    PubMed

    Ashizawa, Tadashi; Akiyama, Yasuto; Miyata, Haruo; Iizuka, Akira; Komiyama, Masaru; Kume, Akiko; Omiya, Maho; Sugino, Takashi; Asai, Akira; Hayashi, Nakamasa; Mitsuya, Koichi; Nakasu, Yoko; Yamaguchi, Ken

    2014-07-01

    Glioblastoma multiforme (GBM) is one of the most malignant and aggressive tumors and has a very poor prognosis, with a median survival time of less than 2 years. Once recurrence develops, there are few therapeutic approaches to control the growth of glioblastoma. In particular, temozolomide (TMZ)-resistant (TMZ-R) GBM is very difficult to treat, and a novel approach to overcome resistance is eagerly awaited. Previously, we reported a novel small molecule inhibitor of STAT3 dimerization, STX-0119, as a cancer therapeutic. In the current study, the efficacy of STX-0119 was evaluated against our established TMZ-resistant U87 cell line using quantitative PCR-based gene expression analysis, in vitro assay and animal experiments. The growth inhibitory effect of STX-0119 on U87 and TMZ-R U87 cells was moderate (IC₅₀, 34 and 45 µM, respectively). In particular, STX-0119 did not show significant inhibition of U87 tumor growth; however, it suppressed the growth of the TMZ-R U87 tumor in nude mice by more than 50%, and prolonged the median survival time compared to the control group. Quantitative PCR revealed that YKL-40, MAGEC1, MGMT, several EMT genes, mesenchymal genes and STAT3 target genes were upregulated, but most of those genes were downregulated by STX-0119 treatment. Furthermore, the invasive activity of TMZ-R U87 cells was significantly inhibited by STX-0119. YKL-40 levels in TMZ-R U87 cells and their supernatants were significantly decreased by STX-0119 administration. These results suggest that STX-0119 is an efficient therapeutic to overcome TMZ resistance in recurrent GBM tumors, and could be the next promising compound leading to survival prolongation, and YKL-40 may be a possible surrogate marker for STAT3 targeting.

  18. Phase 1b study of lenvatinib (E7080) in combination with temozolomide for treatment of advanced melanoma

    PubMed Central

    Hong, David S.; Kurzrock, Razelle; Falchook, Gerald S.; Andresen, Corina; Kwak, Jennifer; Ren, Min; Xu, Lucy; George, Goldy C.; Kim, Kevin B.; Nguyen, Ly M.; O'Brien, James P.; Nemunaitis, John

    2015-01-01

    Objective and Methods In this phase 1b study, patients with stage 4 or unresectable stage 3 melanoma were treated with escalating doses of lenvatinib (once daily) and temozolomide (TMZ) (days 1–5) in 28-day cycles, to determine the maximum tolerated dose (MTD) of the combination. Dose Level (DL)1: lenvatinib 20 mg, TMZ 100 mg/m2; DL2: lenvatinib 24 mg, TMZ 100 mg/m2; DL3: lenvatinib 24 mg, TMZ 150 mg/m2. Adverse events (AEs) were recorded and tumor response assessed per RECIST 1.0. Results Dose-limiting toxicity occurred in 1 of 32 treated patients (DL1); MTD was not reached. The highest dose administered was lenvatinib 24 mg + TMZ 150 mg/m2. Most common treatment-related AEs included fatigue (56.3%), hypertension (53.1%), and proteinuria (46.9%). Overall objective response rate was 18.8% (6 patients), all partial response; (DL1, n = 1; DL3, n = 5). Stable disease (SD) ≥ 16 weeks was observed in 28.1% of patients (DL1 and DL2, n = 1 each; DL3, n = 7); 12.5% of patients had SD ≥ 23 weeks. Single and repeat-dose pharmacokinetics of lenvatinib were comparable across cycles and with concomitant TMZ administration. Conclusion Lenvatinib 24 mg/day + TMZ 150 mg/m2/day (days 1–5) demonstrated modest clinical activity, an acceptable safety profile, and was administered without worsening of either lenvatinib- or TMZ-related toxicities in this patient group. PMID:26503473

  19. Temozolomide in combination with metformin act synergistically to inhibit proliferation and expansion of glioma stem-like cells

    PubMed Central

    YU, ZHIYUN; ZHAO, GANG; LI, PENGLIANG; LI, YUNQIAN; ZHOU, GUANGTONG; CHEN, YONG; XIE, GUIFANG

    2016-01-01

    Glioblastoma is the most common and most aggressive brain tumor in adults. The introduction of temozolomide (TMZ) has advanced chemotherapy for malignant gliomas, but it is not curative. The difficulties in treating glioblastoma may be as a result of the presence of glioma stem cells (GSCs), which are a source of relapse and chemoresistance. Another reason may be that endogenous Akt kinase activity may be activated in response to clinically relevant concentrations of TMZ. Akt activation is correlated with the increased tumorigenicity, invasiveness and stemness of cancer cells and overexpression of an active form of Akt increases glioma cell resistance to TMZ. Mounting evidence has demonstrated that cancer stem cells are preferentially sensitive to an inhibitor of Akt and down-regulation of the PI3K/Akt pathway may enhance the cytotoxicity of TMZ. Metformin (MET), the first-line drug for treating diabetes, it has been proved that it reduces AKT activation and selectively kills cancer stem cells, but whether it can potentiate the cytotoxicity of TMZ for GSCs remains unknown. In the present study, the GSCs isolated from human glioma cell line U87 and Rat glioma cell line C6, in vitro treatment with TMZ either alone or with MET. The present study demonstrates that MET acts synergistically with TMZ in inhibiting GSCs proliferation and generating the highest apoptotic rates when compared to either drug alone. These findings implicate that GSCs cytotoxicity mediated by TMZ may be stimulated by MET, have a synergistic effect, but the definite mechanisms remain elusive. PMID:27073554

  20. NKG2D- and T-cell receptor-dependent lysis of malignant glioma cell lines by human γδ T cells: Modulation by temozolomide and A disintegrin and metalloproteases 10 and 17 inhibitors

    PubMed Central

    Chitadze, Guranda; Lettau, Marcus; Luecke, Stefanie; Wang, Ting; Janssen, Ottmar; Fürst, Daniel; Mytilineos, Joannis; Wesch, Daniela; Oberg, Hans-Heinrich; Held-Feindt, Janka; Kabelitz, Dieter

    2016-01-01

    ABSTRACT The interaction of the MHC class I-related chain molecules A and B (MICA and MICB) and UL-16 binding protein (ULBP) family members expressed on tumor cells with the corresponding NKG2D receptor triggers cytotoxic effector functions in NK cells and γδ T cells. However, as a mechanism of tumor immune escape, NKG2D ligands (NKG2DLs) can be released from the cell surface. In this study, we investigated the NKG2DL system in different human glioblastoma (GBM) cell lines, the most lethal brain tumor in adults. Flow cytometric analysis and ELISA revealed that despite the expression of various NKG2DLs only ULBP2 is released as a soluble protein via the proteolytic activity of “a disintegrin and metalloproteases” (ADAM) 10 and 17. Moreover, we report that temozolomide (TMZ), a chemotherapeutic agent in clinical use for the treatment of GBM, increases the cell surface expression of NKG2DLs and sensitizes GBM cells to γδ T cell-mediated lysis. Both NKG2D and the T-cell receptor (TCR) are involved. The cytotoxic activity of γδ T cells toward GBM cells is strongly enhanced in a TCR-dependent manner by stimulation with pyrophosphate antigens. These data clearly demonstrate the complexity of mechanisms regulating NKG2DL expression in GBM cells and further show that treatment with TMZ can increase the immunogenicity of GBM. Thus, TMZ might enhance the potential of the adoptive transfer of ex vivo expanded γδ T cells for the treatment of malignant glioblastoma. PMID:27141377

  1. Pharmacokinetics and antitumor efficacy of DSPE-PEG2000 polymeric liposomes loaded with quercetin and temozolomide: Analysis of their effectiveness in enhancing the chemosensitization of drug-resistant glioma cells

    PubMed Central

    HU, JUN; WANG, JUNJIE; WANG, GANG; YAO, ZHONGJUN; DANG, XIAOQIAN

    2016-01-01

    In the present study, a new type of DSPE-PEG2000 polymeric liposome for the brain-targeted delivery of poorly water-soluble anticancer drugs was successfully prepared and characterized. The nanoparticles were formed by the self-assembly of an amphiphilic polymer consisting of hydrophilic 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)-2000] (DSPE-PEG2000). These nanoliposomes served as a safe delivery platform for the simultaneous delivery of quercetin (QUE) and temozolomide (TMZ) to rat brains. The 2-in-1 PEG2000-DSPE nanoliposomes containing QUE and TMZ (QUE/TMZ-NLs) were rapidly taken up by the U87 glioma cells in vitro, whereas at the same concentrations, the amounts of the free drugs taken up were minimal. The QUE/TMZ-NLs showed an enhanced potency in the U87 cells and the TMZ-resistant U87 cells (U87/TR cells), possibly due to the high intracellular drug concentration and the subsequent drug release. In vivo biodistribution experiments revealed a significant accumulation of QUE/TMZ-NLs in the brain, with significantly increased plasma concentrations of QUE and TMZ, as well as delayed clearance in our rat model of glioma. The results were not so significant for the QUE-loaded nanoliposomes (QUE-NLs) and free TMZ. The findings of our study establish the DSPE-PEG2000 polymeric liposome as a novel and effective nanocarrier for enhancing drug delivery to brain tumors. PMID:26782731

  2. Marked response of gliomatosis cerebri to temozolomide and whole brain radiotherapy.

    PubMed

    Mattox, Austin K; Lark, Amy L; Adamson, D Cory

    2012-05-01

    Gliomatosis cerebri (GC) represents an unfortunate, rare variant of glioma with a very poor prognosis. Given this lesion's rarity, little information exists on appropriate treatment options. The diffuse, infiltrative nature of GC precludes any surgical resection and limits therapy. Because of the improved survival seen with the use of temozolomide (TMZ) in malignant glioma, a rigorous systematic review of the published literature was performed to ascertain the benefit of TMZ in GC. We identified all GC cases in the literature where there was enough information to ascertain a clear response to a specific chemoradiotherapeutic treatment. In addition to our experience with a recent case, we have identified 61 patients with GC in the published literature who demonstrated a positive radiographic or clinic response after treatment. Statistical analysis of survival was performed by Kaplan-Meier analysis. A positive radiographic and clinical response was seen in patients ranging in age from 4 to 84 years. Overall median survival in patients diagnosed with GC who demonstrated a response after treatment was 25 months, with 1- and 2-year survival rates of 89% and 55%, respectively. The most common treatment regimens for responders included TMZ alone (26.2%), external whole-brain radiotherapy (WBRT) (26.2%), and concomitant TMZ and WBRT (20%). Our patient was treated with concomitant TMZ (150 mg/m(2)/day over 5 days) and WBRT (50 Gy) and has remained with a complete radiographic response after 36 months. In conclusion, patients with GC confirmed by surgical biopsy should be aggressively treated with concomitant TMZ and WBRT, as marked responses have been seen, and this appears to offer overall survival benefit.

  3. Phase I Study of Vandetanib With Radiotherapy and Temozolomide for Newly Diagnosed Glioblastoma

    SciTech Connect

    Drappatz, Jan; Norden, Andrew D.; Wong, Eric T.

    2010-09-01

    Purpose: Increasing evidence has suggested that angiogenesis inhibition might potentiate the effects of radiotherapy and chemotherapy in patients with glioblastoma (GBM). In addition, epidermal growth factor receptor inhibition might be of therapeutic benefit, because the epidermal growth factor receptor is upregulated in GBM and contributes to radiation resistance. We conducted a Phase I study of vandetanib, an inhibitor of vascular endothelial growth factor receptor 2 and epidermal growth factor receptor, in patients with newly diagnosed GBM combined with RT and temozolomide (TMZ). Methods and Materials: A total of 13 GBM patients were treated with vandetanib, radiotherapy, and concurrent and adjuvant TMZ, using a standard '3 + 3' dose escalation. The maximal tolerated dose was defined as the dose with <1 of 6 dose-limiting toxicities during the first 12 weeks of therapy. The eligible patients were adults with newly diagnosed GBM, Karnofsky performance status of {>=}60, normal organ function, who were not taking enzyme-inducing antiepileptic drugs. Results: Of the 13 patients, 6 were treated with vandetanib at a dose of 200mg daily. Of the 6 patients, 3 developed dose-limiting toxicities within the first 12 weeks, including gastrointestinal hemorrhage and thrombocytopenia in 1 patient, neutropenia in 1 patient, and diverticulitis with gastrointestinal perforation in 1 patient. The other 7 patients were treated with 100 mg daily, with no dose-limiting toxicities observed, establishing this dose as the maximal tolerated dose combined with TMZ and RT. Conclusion: Vandetanib can be safely combined with RT and TMZ in GBM patients. A Phase II study in which patients are randomized to vandetanib 100 mg daily with RT and TMZ or RT and TMZ alone is underway.

  4. Postoperative Treatment of Primary Glioblastoma Multiforme With Radiation and Concomitant Temozolomide in Elderly Patients

    SciTech Connect

    Combs, Stephanie E. Wagner, Johanna; Bischof, Marc; Welzel, Thomas; Wagner, Florian; Debus, Juergen; Schulz-Ertner, Daniela

    2008-03-15

    Purpose: To evaluate efficacy and toxicity in elderly patients with glioblastoma multiforme (GBM) treated with postoperative radiochemotherapy with temozolomide (TMZ). Patients and Methods: Forty-three patients aged 65 years or older were treated with postoperative with radiochemotherapy using TMZ for primary GBM. Median age at primary diagnosis was 67 years; 14 patients were female, 29 were male. A complete surgical resection was performed in 12 patients, subtotal resection in 17 patients, and biopsy only in 14 patients. Radiotherapy was applied with a median dose of 60 Gy, in a median fractionation of 5 x 2 Gy/wk. Thirty-five patients received concomitant TMZ at 50 mg/m{sup 2}, and in 8 patients 75 mg/m{sup 2} of TMZ was applied. Adjuvant cycles of TMZ were prescribed in 5 patients only. Results: Median overall survival was 11 months in all patients; the actuarial overall survival rate was 48% at 1 year and 8% at 2 years. Median overall survival was 18 months after complete resection, 16 months after subtotal resection, and 6 months after biopsy only. Median progression-free survival was 4 months; the actuarial progression-free survival rate was 41% at 6 months and 18% at 12 months. Radiochemotherapy was well tolerated in most patients and could be completed without interruption in 38 of 43 patients. Four patients developed hematologic side effects greater than Common Terminology Criteria Grade 2, which led to early discontinuation of TMZ in 1 patient. Conclusions: Radiochemotherapy is safe and effective in a subgroup of elderly patients with GBM and should be considered in patients without major comorbidities.

  5. Phase I Study of Vorinostat in Combination with Temozolomide in Patients with High-Grade Gliomas: North American Brain Tumor Consortium Study 04-03

    PubMed Central

    Lee, Eudocia Q.; Puduvalli, Vinay K.; Reid, Joel M.; Kuhn, John G.; Lamborn, Kathleen R.; Cloughesy, Timothy F.; Chang, Susan M.; Drappatz, Jan; Yung, W. K. Alfred; Gilbert, Mark R.; Robins, H. Ian; Lieberman, Frank S.; Lassman, Andrew B.; McGovern, Renee M.; Xu, Jihong; Desideri, Serena; Ye, Xiabu; Ames, Matthew M.; Espinoza-Delgado, Igor; Prados, Michael D.; Wen, Patrick Y.

    2013-01-01

    Purpose A phase I, dose-finding study of vorinostat in combination with temozolomide (TMZ) was conducted to determine the maximum tolerated dose (MTD), safety, and pharmacokinetics in patients with high-grade glioma (HGG). Experimental Design This phase I, dose-finding, investigational study was conducted in two parts. Part 1 was a dose-escalation study of vorinostat in combination with TMZ 150 mg/m2/day × 5 days every 28 days. Part 2 was a dose-escalation study of vorinostat in combination with TMZ 150 mg/m2/day × 5 days of the first cycle and 200 mg/m2/day × 5 days of the subsequent 28-day cycles. Results In Part 1, the MTD of vorinostat administered on days 1-7 and 15-21 of every 28 day cycle in combination with TMZ was 500 mg daily. Dose-limiting toxicities (DLTs) included grade 3 anorexia, grade 3 ALT, and grade 5 hemorrhage in the setting of grade 4 thrombocytopenia. In Part 2, the MTD of vorinostat on days 1-7 and 15-21 of every 28 day cycle combined with TMZ was 400 mg daily. No DLTs were encountered, but vorinostat dosing could not be escalated further due to thrombocytopenia. The most common serious adverse events were fatigue, lymphopenia, thrombocytopenia, and thromboembolic events. There were no apparent pharmacokinetic interactions between vorinostat and TMZ. Vorinostat treatment resulted in hyperacetylation of histones H3 and H4 in peripheral mononuclear cells. Conclusion Vorinostat in combination with temozolomide is well-tolerated in patients with HGG. A phase I/II trial of vorinostat with radiotherapy and concomitant TMZ in newly diagnosed glioblastoma is underway. PMID:22923449

  6. Temozolomide Resistance in Glioblastoma Cell Lines: Implication of MGMT, MMR, P-Glycoprotein and CD133 Expression

    PubMed Central

    Prados, Jose; Caba, Octavio; Cabeza, Laura; Berdasco, Maria; Gónzalez, Beatriz; Melguizo, Consolación

    2015-01-01

    Background The use of temozolomide (TMZ) has improved the prognosis for glioblastoma multiforme patients. However, TMZ resistance may be one of the main reasons why treatment fails. Although this resistance has frequently been linked to the expression of O6-methylguanine-DNA methyltransferase (MGMT) it seems that this enzyme is not the only molecular mechanism that may account for the appearance of drug resistance in glioblastoma multiforme patients as the mismatch repair (MMR) complex, P-glycoprotein, and/or the presence of cancer stem cells may also be implicated. Methods Four nervous system tumor cell lines were used to analyze the modulation of MGMT expression and MGMT promoter methylation by TMZ treatment. Furthermore, 5-aza-2’-deoxycytidine was used to demethylate the MGMT promoter and O(6)-benzylguanine to block GMT activity. In addition, MMR complex and P-glycoprotein expression were studied before and after TMZ exposure and correlated with MGMT expression. Finally, the effect of TMZ exposure on CD133 expression was analyzed. Results Our results showed two clearly differentiated groups of tumor cells characterized by low (A172 and LN229) and high (SF268 and SK-N-SH) basal MGMT expression. Interestingly, cell lines with no MGMT expression and low TMZ IC50 showed a high MMR complex expression, whereas cell lines with high MGMT expression and high TMZ IC50 did not express the MMR complex. In addition, modulation of MGMT expression in A172 and LN229 cell lines was accompanied by a significant increase in the TMZ IC50, whereas no differences were observed in SF268 and SK-N-SH cell lines. In contrast, P-glycoprotein and CD133 was found to be unrelated to TMZ resistance in these cell lines. Conclusions These results may be relevant in understanding the phenomenon of TMZ resistance, especially in glioblastoma multiforme patients laking MGMT expression, and may also aid in the design of new therapeutic strategies to improve the efficacy of TMZ in glioblastoma

  7. Inhibition of MMP14 potentiates the therapeutic effect of temozolomide and radiation in gliomas.

    PubMed

    Ulasov, Ilya; Thaci, Bart; Sarvaiya, Purvaba; Yi, Ruiyang; Guo, Donna; Auffinger, Brenda; Pytel, Peter; Zhang, Lingjiao; Kim, Chung Kwon; Borovjagin, Anton; Dey, Mahua; Han, Yu; Baryshnikov, Anatoly Y; Lesniak, Maciej S

    2013-08-01

    Metalloproteinases are membrane-bound proteins that play a role in the cellular responses to antiglioma therapy. Previously, it has been shown that treatment of glioma cells with temozolomide (TMZ) and radiation (XRT) induces the expression of metalloproteinase 14 (MMP14). To investigate the role of MMP14 in gliomagenesis, we used several chemical inhibitors which affect MMP14 expression. Of all the inhibitors tested, we found that Marimastat not only inhibits the expression of MMP14 in U87 and U251 glioma cells, but also induces cell cycle arrest. To determine the relationship between MMP14 inhibition and alteration of the cell cycle, we used an RNAi technique. Genetic knockdown of MMP14 in U87 and U251 glioma cells induced G2/M arrest and decreased proliferation. Mechanistically, we show that TMZ and XRT regulated expression of MMP14 in clinical samples and in vitro models through downregulation of microRNA374. In vivo genetic knockdown of MMP14 significantly decreased tumor growth of glioma xenografts and improved survival of glioma-bearing mice. Moreover, the combination of MMP14 silencing with TMZ and XRT significantly improved the survival of glioma-bearing mice compared to a single modality treatment group. Therefore, we show that the inhibition of MMP14 sensitizes tumor cells to TMZ and XRT and could be used as a future strategy for antiglioma therapy.

  8. Inhibition of MNK pathways enhances cancer cell response to chemotherapy with temozolomide and targeted radionuclide therapy.

    PubMed

    Grzmil, Michal; Seebacher, Jan; Hess, Daniel; Behe, Martin; Schibli, Roger; Moncayo, Gerald; Frank, Stephan; Hemmings, Brian A

    2016-09-01

    Current standard-of-care treatment for malignant cancers includes radiotherapy and adjuvant chemotherapy. Here, we report increased MAP kinase-interacting kinase (MNK)-regulated phosphorylation of translation initiation factor 4E (eIF4E) in glioma cells upon temozolomide (TMZ) treatment and in medullary thyroid carcinoma (MTC) cells in response to targeted radionuclide therapy. Depletion of MNK activity by using two MNK inhibitors, CGP57380 or cercosporamide, as well as by MNK1-specific knockdown sensitized glioblastoma (GBM) cells and GBM-derived spheres to TMZ. Furthermore, CGP57380 treatment enhanced response of MTC cells to (177)Lu-labeled gastrin analogue. In order to understand how MNK signaling pathways support glioma survival we analyzed putative MNK substrates by quantitative phosphoproteomics in normal condition and in the presence of TMZ. We identified MNK inhibitor-sensitive phosphorylation sites on eIF4G1, mutations of which either influenced eIF4E phosphorylation or glioma cell response to TMZ, pointing to altered regulation of translation initiation as a resistance mechanism. Pharmacological inhibition of overexpressed MNK1 by CGP57380 reduced eIF4E phosphorylation and induced association of inactive MNK1 with eIF4G1. Taken together, our data show an activation of MNK-mediated survival mechanisms in response to either glioma chemotherapy or MTC targeted radiation and suggest that inhibition of MNK activity represents an attractive sensitizing strategy for cancer treatments.

  9. Could the Anti-Chaperone VER155008 Replace Temozolomide for Glioma Treatment

    PubMed Central

    Shervington, Leroy; Patil, Harshada; Shervington, Amal

    2015-01-01

    Cancer inducible molecular chaperone HSP90 is of great importance as an anticancer target. Proteomic analysis showed that inhibiting HSP90 by the geldanamycin derivative, 17-AAG elevated the expression of the co-chaperone Hsp70. In this study we used HSP90 selective inhibitor 17-AAG and HSP70/90 dual inhibitor, VER155008 (VER) in U87-MG glioma cells. miRNAs microarray technology was used to evaluate the efficacy of these inhibitory drugs compared with temozolomide (TMZ), used as a standard treatment for glioma. Microarrays data identified 154 differentially expressed miRNAs using stringent or unstringent parameters. 16 miRNAs were overlapped between treatments, 13 upregulated and one downregulated miRNA were overlapped between TMZ and VER. The miRNA target prediction software was used for these overlapped miRNAs and identified 6 of the 13 upregulated miRNAs target methyltransferase genes. The IC50, together with Akt and HSP70 and 90 protein level data favour VER and TMZ to 17-AAG, however due to the selectivity of VER to cancer cells as a potent antichaperon, it may be more favourable to the standard TMZ. PMID:26185541

  10. HDAC6 promotes cell proliferation and confers resistance to temozolomide in glioblastoma.

    PubMed

    Wang, Zhihao; Hu, Pengchao; Tang, Fang; Lian, Haiwei; Chen, Xiong; Zhang, Yingying; He, Xiaohua; Liu, Wanhong; Xie, Conghua

    2016-08-28

    Histone deacetylases are considered to be among the most promising targets in drug development for cancer therapy. Histone deacetylase 6 (HDAC6) is a unique cytoplasmic enzyme that regulates many biological processes involved in tumorigenesis through its deacetylase and ubiquitin-binding activities. Here, we report that HDAC6 is overexpressed in glioblastoma tissues and cell lines. Overexpression of HDAC6 promotes the proliferation and spheroid formation of glioblastoma cells. HDAC6 overexpression confers resistance to temozolomide (TMZ) mediated cell proliferation inhibition and apoptosis induction. Conversely, knockdown of HDAC6 inhibits cell proliferation, impairs spheroid formation and sensitizes glioblastoma cells to TMZ. The inhibition of HDAC6 deacetylase activity by selective inhibitors inhibits the proliferation of glioblastoma cells and induces apoptosis. HDAC6 selective inhibitors can sensitize glioblastoma cells to TMZ. Moreover, we showed that HDAC6 mediated EGFR stabilization might partly account for its oncogenic role in glioblastoma. TMZ resistant glioblastoma cells showed higher expression of HDAC6 and more activation of EGFR. HDAC6 inhibitors decrease EGFR protein levels and impair the activation of the EGFR pathway. Taken together, our results suggest that the inhibition of HDAC6 may be a promising strategy for the treatment of glioblastoma.

  11. Synergistic inhibition of angiogenesis and glioma cell-induced angiogenesis by the combination of temozolomide and enediyne antibiotic lidamycin

    PubMed Central

    Li, Xing-qi; Ouyang, Zhi-gang; Zhang, Sheng-hua; Liu, Hong; Shang, Yue; Li, Yi; Zhen, Yong-su

    2014-01-01

    Present work mainly evaluated the inhibitory effects of lidamycin (LDM), an enediyne antibiotic, on angiogenesis or glioma-induced angiogenesis in vitro and in vivo, especially its synergistic anti-angiogenesis with temozolomide (TMZ). LDM alone efficiently inhibited proliferations and induced apoptosis of rat brain microvessel endothelial cells (rBMEC). LDM also interrupted the tube formation of rat brain microvessel endothelial cells (rBMEC) and rat aortic ring spreading. The blockade of rBMEC invasion and C6 cell-induced rBMEC migration by LDM was associated with decrease of VEGF secretion in a co-culture system. TMZ dramatically potentiated the effects of LDM on anti-proliferation, apoptosis induction, and synergistically inhibited angiogenesis events. As determined by western blot and ELISA, the interaction of tumor cells and the rBMEC was markedly interrupted by LDM plus TMZ with synergistic regulations of VEGF induced angiogenesis signal pathway, tumor cell invasion/migration, and apoptosis signal pathway. Immunofluorohistochemistry of CD31 and VEGF showed that LDM plus TMZ resulted in synergistic decrease of microvessel density (MVD) and VEGF expression in human glioma U87 cell subcutaneous xenograft. This study indicates that the high efficacy of LDM and the synergistic effects of LDM plus TMZ against glioma are mediated, at least in part, by the potentiated anti-angiogenesis. PMID:24424202

  12. Unraveling the cytotoxic potential of Temozolomide loaded into PLGA nanoparticles

    PubMed Central

    2014-01-01

    Background Nanotechnology has received great attention since a decade for the treatment of different varieties of cancer. However, there is a limited data available on the cytotoxic potential of Temozolomide (TMZ) formulations. In the current research work, an attempt has been made to understand the anti-metastatic effect of the drug after loading into PLGA nanoparticles against C6 glioma cells. Nanoparticles were prepared using solvent diffusion method and were characterized for size and morphology. Diffusion of the drug from the nanoparticles was studied by dialysis method. The designed nanoparticles were also assessed for cellular uptake using confocal microscopy and flow cytometry. Results PLGA nanoparticles caused a sustained release of the drug and showed a higher cellular uptake. The drug formulations also affected the cellular proliferation and motility. Conclusion PLGA coated nanoparticles prolong the activity of the loaded drug while retaining the anti-metastatic activity. PMID:24410831

  13. Smac mimetic-induced upregulation of interferon-β sensitizes glioblastoma to temozolomide-induced cell death

    PubMed Central

    Marschall, V; Fulda, S

    2015-01-01

    Inhibitor of apoptosis (IAP) proteins are frequently expressed at high levels in cancer cells and represent attractive therapeutic targets. We previously reported that the Smac (second mitochondria-derived activator of caspases) mimetic BV6, which antagonizes IAP proteins, sensitizes glioblastoma cells to temozolomide (TMZ)-induced cell death in a nuclear factor-κB (NF-κB)-dependent manner. However, BV6-induced NF-κB target genes responsible for this synergistic interaction have remained elusive. Using whole-genome gene expression profiling, we here identify BV6-stimulated, NF-κB-dependent transcriptional upregulation of interferon-β (IFNβ) and IFN-mediated proapoptotic signaling as critical events that mediate BV6/TMZ-induced apoptosis. Knockdown of IFNβ significantly rescues cells from BV6/TMZ-induced cell death. Similarly, silencing of the corresponding receptor IFNα/β receptor (IFNAR) confers a significant protection against apoptosis, demonstrating that IFNβ and IFN signaling are required for BV6/TMZ-mediated cell death. Moreover, BV6 and TMZ cooperate to transcriptionally upregulate the proapoptotic B-cell lymphoma 2 family proteins Bax (Bcl-2-associated X protein) or Puma (p53-upregulated modulator of apoptosis). Knockdown of Bax or Puma significantly decreases BV6/TMZ-induced apoptosis, showing that both proteins are necessary for apoptosis. By identifying IFNβ as a key mediator of BV6/TMZ-induced apoptosis, our study provides novel insights into the underlying molecular mechanisms of Smac mimetic-mediated chemosensitization with important implications for the development of novel treatment strategies for glioblastoma. PMID:26379193

  14. Temozolomide-Induced Shrinkage of Invasive Pituitary Adenoma in Patient with Nelson's Syndrome: A Case Report and Review of the Literature

    PubMed Central

    Kurowska, Maria; Nowakowski, Andrzej; Zieliński, Grzegorz; Malicka, Joanna; Tarach, Jerzy S.; Maksymowicz, Maria; Denew, Piotr

    2015-01-01

    Introduction. Invasive tumours in Nelson's syndrome need aggressive therapy. Recent reports have documented the efficacy of temozolomide (TMZ) in the treatment of adenomas resistant to conventional management. Objective. The review of the literature concerning TMZ treatment of atypical corticotroph adenomas and a case study of 56-year-old woman who developed Nelson's syndrome. Treatment Proceeding. The patient with Cushing's disease underwent transsphenoidal adenomectomy followed by a 27-month-long period of remission. Due to a regrowth of the tumor, she underwent two reoperations followed by stereotactic radiotherapy. Because of treatment failures, bilateral adrenalectomy was performed. Then she developed Nelson's syndrome. A fourth transsphenoidal adenomectomy was performed, but there was a rapid recurrence. Five months later, she underwent a right frontotemporal craniotomy. Due to a rapid regrowth of the tumour, the patient did not receive gamma-knife therapy and was treated with cabergoline and somatostatin analogue for some time. Only TMZ therapy resulted in marked clinical, biochemical, and radiological improvement. To date, this is the first case of invasive corticotroph adenoma in Nelson's syndrome treated with temozolomide in Poland. Conclusion. In our opinion, temozolomide can be an effective treatment option of invasive adenomas in Nelson's syndrome. PMID:26221547

  15. Combined Delivery of Temozolomide and Anti-miR221 PNA Using Mesoporous Silica Nanoparticles Induces Apoptosis in Resistant Glioma Cells.

    PubMed

    Bertucci, Alessandro; Prasetyanto, Eko Adi; Septiadi, Dedy; Manicardi, Alex; Brognara, Eleonora; Gambari, Roberto; Corradini, Roberto; De Cola, Luisa

    2015-11-11

    Mesoporous silica nanoparticles (MSNPs), 100 nm in size, incorporating a Cy5 fluorophore within the silica framework, are synthesized and loaded with the anti-cancer drug temozolomide (TMZ), used in the treatment of gliomas. The surface of the particles is then decorated, using electrostatic interactions, with a polyarginine-peptide nucleic acid (R8-PNA) conjugate targeting the miR221 microRNA. The multi-functional nanosystem thus obtained is rapidly internalized into glioma C6 or T98G cells. The anti-miR activity of the PNA is retained, as confirmed by reverse transcription polymerase chain reaction (RT-PCR) measurements and induction of apoptosis is observed in temozolomide-resistant cell lines. The TMZ-loaded MSNPs show an enhanced pro-apoptotic effect, and the combined effect of TMZ and R8-PNA in the MSNPs shows the most effective induction of apoptosis (70.9% of apoptotic cells) thus far achieved in the temozolomide-resistant T98G cell line. PMID:26395266

  16. Combination of lentivirus-mediated silencing of PPM1D and temozolomide chemotherapy eradicates malignant glioma through cell apoptosis and cell cycle arrest

    PubMed Central

    Wang, Peng; Ye, Jing-An; Hou, Chong-Xian; Zhou, Dong; Zhan, Sheng-Quan

    2016-01-01

    Temozolomide (TMZ) is approved for use as first-line treatment for glioblastoma multiforme (GBM). However, GBM shows chemoresistance shortly after the initiation of treatment. In order to detect whether silencing of human protein phosphatase 1D magnesium dependent (PPM1D) gene could increase the effects of TMZ in glioma cells, glioma cells U87-MG were infected with lentiviral shRNA vector targeting PPM1D silencing. After PPM1D silencing was established, cells were treated with TMZ. The multiple functions of human glioma cells after PPM1D silencing and TMZ chemotherapy were detected by flow cytometry and MTT assay. Significantly differentially expressed genes were distinguished by microarray-based gene expression profiling and analyzed by gene pathway enrichment analysis and ontology assessment. Western blotting was used to establish the protein expression of the core genes. PPM1D gene silencing improves TMZ induced cell proliferation and induces cell apoptosis and cell cycle arrest. When PPM1D gene silencing combined with TMZ was performed in glioma cells, 367 genes were upregulated and 444 genes were downregulated compared with negative control. The most significant differential expression pathway was pathway in cancer and IGFR1R, PIK3R1, MAPK8 and EP300 are core genes in the network. Western blotting showed that MAPK8 and PIK3R1 protein expression levels were upregulated and RB1 protein expression was decreased. It was consistent with that detected in gene expression profiling. In conclusion, PPM1D gene silencing combined with TMZ eradicates glioma cells through cell apoptosis and cell cycle arrest. PIK3R1/AKT pathway plays a role in the multiple functions of glioma cells after PPM1D silencing and TMZ chemotherapy. PMID:27633132

  17. Comparison of long-term survival between temozolomide-based chemoradiotherapy and radiotherapy alone for patients with low-grade gliomas after surgical resection

    PubMed Central

    Gai, Xiu-juan; Wei, Yu-mei; Tao, Heng-min; An, Dian-zheng; Sun, Jia-teng; Li, Bao-sheng

    2016-01-01

    Purpose This study was designed to compare the survival outcomes of temozolomide-based chemoradiotherapy (TMZ + RT) vs radiotherapy alone (RT-alone) for low-grade gliomas (LGGs) after surgical resection. Patients and methods In this retrospective analysis, we reviewed postoperative records of 69 patients with LGGs treated with TMZ + RT (n=31) and RT-alone (n=38) at the Shandong Cancer Hospital Affiliated to Shandong University between June 2011 and December 2013. Patients in the TMZ + RT group were administered 50–100 mg oral TMZ every day until the radiotherapy regimen was completed. Results The median follow-up since surgery was 33 months and showed no significant intergroup differences (P=0.06). There were statistically significant intergroup differences in the progression-free survival rate (P=0.037), with 83.9% for TMZ-RT group and 60.5% for RT-alone group. The overall 2-year overall survival (OS) rate was 89.86%. Age distribution (≥45 years and <45 years) and resection margin (complete resection or not) were significantly associated with OS (P=0.03 and P=0.004, respectively). Conclusion Although no differences were found in the 2-year OS between the TMZ + RT and RT-alone groups, there was a trend toward increased 2-year progression-free survival in the TMZ + RT group. With better tolerability, concurrent TMZ chemoradiotherapy may be beneficial for postoperative patients with LGGs. Age distribution and surgical margin are likely potential indicators of disease prognosis. The possible differences in long-term survival between the two groups and the links between prognostic factors and long-term survival may be worthy of further investigation. PMID:27574452

  18. High expression of miR-9 in CD133+ glioblastoma cells in chemoresistance to temozolomide

    PubMed Central

    Munoz, Jessian L.; Rodriguez-Cruz, Vivian; Rameshwar, Pranela

    2016-01-01

    Glioblastoma Multiforme (GBM), a uniformly lethal stage IV astrocytoma, is currently treated with a combination of surgical and radiation therapy as well as Temozolomide (TMZ) chemotherapy. Resistance to TMZ is rapidly acquired by GBM cells and overcoming this resistance has been an area of signi?cant research. GBM 'cancer stem cells' (CSC) also known as 'cancer initiating cells' are often positively selected by CD133 expression and TMZ resistance. In this project, we selected GBM CSC from two cell lines based on CD133 expression. CD133+ and CD133− GBM cells showed comparable cell cycle status. The expression of genes within the Sonic Hedgehog Signaling pathway, PTCH1 (SHH receptor/basal signaling repressor) and Gli1 (effector transcription factor) were increased. The recent literature indicated a decreased in PTCH expression by miRNA and this was independent of SHH expression. We analyzed 5 potential PTCH-targeting miRNA and identi?ed an increase in miRNA-9-2. The CD133+ cells showed an increase in the Multiple Drug Resistance 1 gene (MDR1). Knockdown of Gli1 and MDR1 with siRNA enhanced TMZ induced cell death. Taken together, these studies show CD133+ GBM CSCs expressed greater levels of miR-9 and activation of the SHH/PTCH1/MDR1 axis. This axis has been shown to impart TMZ resistance. In the case of the CD133+ cells, the resistance is not acquires but seems to be inherent. Identi?cation of this pathway as well as the identi?cation of miR-9 may allow for the development of miRNA-targeted approach to Cancer Stem Cell therapy in GBM. PMID:27347493

  19. Transport of treosulfan and temozolomide across an in-vitro blood-brain barrier model.

    PubMed

    Linz, Ute; Hupert, Michelle; Santiago-Schübel, Beatrix; Wien, Sascha; Stab, Julia; Wagner, Sylvia

    2015-08-01

    In vitro, treosulfan (TREO) has shown high effectiveness against malignant gliomas. However, a first clinical trial for newly diagnosed glioblastoma did not show any positive effect. Even though dosing and timing might have been the reasons for this failure, it might also be that TREO does not reach the brain in sufficient amount. Surprisingly, there are no published data on TREO uptake into the brain of patients, despite extensive research on this compound. An in-vitro blood-brain barrier (BBB) model consisting of primary porcine brain capillary endothelial cells was used to determine the transport of TREO across the cell monolayer. Temozolomide (TMZ), the most widely used cytotoxic drug for malignant gliomas, served as a reference. An HPLC-ESI-MS/MS procedure was developed to detect TREO and TMZ in cell culture medium. Parallel to the experimental approach, the permeability of TREO and the reference substance across the in-vitro BBB was estimated on the basis of their physicochemical properties. The detection limit was 30 nmol/l for TREO and 10 nmol/l for TMZ. Drug transport was measured in two directions: influx, apical-to-basolateral (A-to-B), and efflux, basolateral-to-apical (B-to-A). For TREO, the A-to-B permeability was lower (1.6%) than the B-to-A permeability (3.0%). This was in contrast to TMZ, which had higher A-to-B (13.1%) than B-to-A (7.2%) permeability values. The in-vitro BBB model applied simulated the human BBB properly for TMZ. It is, therefore, reasonable to assume that the values for TREO are also meaningful. Considering the lack of noninvasive, significant alternative methods to study transport across the BBB, the porcine brain capillary endothelial cell model was efficient to collect first data for TREO that explain the disappointing clinical results for this drug against cerebral tumors.

  20. Standard (60 Gy) or Short-Course (40 Gy) Irradiation Plus Concomitant and Adjuvant Temozolomide for Elderly Patients With Glioblastoma: A Propensity-Matched Analysis

    SciTech Connect

    Minniti, Giuseppe; Scaringi, Claudia; Lanzetta, Gaetano; Terrenato, Irene; Esposito, Vincenzo; Arcella, Antonella; Pace, Andrea; Giangaspero, Felice; Bozzao, Alessandro; Enrici, Riccardo Maurizi

    2015-01-01

    Purpose: To evaluate 2 specific radiation schedules, each combined with temozolomide (TMZ), assessing their efficacy and safety in patients aged ≥65 years with newly diagnosed glioblastoma (GBM). Methods and Materials: Patients aged ≥65 years with Karnofsky performance status (KPS) ≥60 who received either standard (60 Gy) or short-course (40 Gy) radiation therapy (RT) with concomitant and adjuvant TMZ between June 2004 and October 2013 were retrospectively analyzed. A propensity score analysis was executed for a balanced comparison of treatment outcomes. Results: A total of 127 patients received standard RT-TMZ, whereas 116 patients underwent short-course RT-TMZ. Median overall survival and progression-free survival times were similar: 12 months and 5.6 months for the standard RT-TMZ group and 12.5 months and 6.7 months for the short-course RT-TMZ group, respectively. Radiation schedule was associated with similar survival outcomes in either unadjusted or adjusted analysis. O{sup 6}-methylguanine-DNA methyltransferase promoter methylation was the most favorable prognostic factor (P=.0001). Standard RT-TMZ therapy was associated with a significant rise in grade 2 and 3 neurologic toxicity (P=.01), lowering of KPS scores during the study (P=.01), and higher posttreatment dosing of corticosteroid (P=.02). Conclusions: In older adults with GBM, survival outcomes of standard and short-course RT-TMZ were similar. An abbreviated course of RT plus TMZ may represent a reasonable therapeutic approach for these patients, without loss of survival benefit and acceptable toxicity.

  1. Phase II Trial of Hypofractionated IMRT With Temozolomide for Patients With Newly Diagnosed Glioblastoma Multiforme

    SciTech Connect

    Reddy, Krishna; Damek, Denise; Gaspar, Laurie E.; Ney, Douglas; Waziri, Allen; Lillehei, Kevin; Stuhr, Kelly; Kavanagh, Brian D.; Chen Changhu

    2012-11-01

    Purpose: To report toxicity and overall survival (OS) in patients with newly diagnosed glioblastoma multiforme (GBM) treated with hypofractionated intensity-modulated radiotherapy (hypo-IMRT) with concurrent and adjuvant temozolomide (TMZ). Methods and Materials: Patients with newly diagnosed GBM after biopsy or resection and with adequate performance status and organ or bone marrow function were eligible for this study. Patients received postoperative hypo-IMRT to the surgical cavity and residual tumor seen on T1-weighted brain MRI with a 5-mm margin to a total dose of 60 Gy in 10 fractions (6 Gy/fraction) and to the T2 abnormality on T2-weighted MRI with 5-mm margin to 30 Gy in 10 fractions (3 Gy/fraction). Concurrent TMZ was given at 75 mg/m{sup 2}/day for 28 consecutive days. Adjuvant TMZ was given at 150 to 200 mg/m{sup 2}/day for 5 days every 28 days. Toxicities were defined using Common Terminology Criteria for Adverse Events version 3.0. Results: Twenty-four patients were treated, consisting of 14 men, 10 women; a median age of 60.5 years old (range, 27-77 years); and a median Karnofsky performance score of 80 (range, 60-90). All patients received hypo-IMRT and concurrent TMZ according to protocol, except for 2 patients who received only 14 days of concurrent TMZ. The median number of adjuvant TMZ cycles was 6.5 (range, 0-14).With a median follow-up of 14.8 months (range, 2.7-34.2 months) for all patients and a minimum follow-up of 20.6 months for living patients, no instances of grade 3 or higher nonhematologic toxicity were observed. The median OS was 16.6 months (range, 4.1-35.9 months). Six patients underwent repeated surgery for suspected tumor recurrence; necrosis was found in 50% to 100% of the resected specimens. Conclusion: In selected GBM patients, 60 Gy hypo-IMRT delivered in 6-Gy fractions over 2 weeks with concurrent and adjuvant TMZ is safe. OS in this small cohort of patients was comparable to that treated with current standard of care

  2. Disulfiram, a drug widely used to control alcoholism, suppresses self-renewal of glioblastoma and overrides resistance to temozolomide

    PubMed Central

    Triscott, Joanna; Lee, Cathy; Hu, Kaiji; Fotovati, Abbas; Berns, Rachel; Pambid, Mary; Luk, Margaret; Kast, Richard E.; Kong, Esther; Toyota, Eric; Yip, Stephen; Toyota, Brian; Dunn, Sandra E.

    2012-01-01

    Glioblastomas (GBM) are associated with high rates of relapse. These brain tumors are often resistant to chemotherapies like temozolomide (TMZ) and there are very few treatment options available to patients. We recently reported that polo-like kinase-1 (PLK1) is associated with the proliferative subtype of GBM; which has the worst prognosis. In this study, we addressed the potential of repurposing disulfiram (DSF), a drug widely used to control alcoholism for the past six decades. DSF has good safety profiles and penetrates the blood-brain barrier. Here we report that DSF inhibited the growth of TMZ resistant GBM cells, (IC90=100 nM), but did not affect normal human astrocytes. At similar DSF concentrations, self-renewal was blocked by ~100% using neurosphere growth assays. Likewise the drug completely inhibited the self-renewal of the BT74 and GBM4 primary cell lines. Additionally, DSF suppressed growth and self-renewal of primary cells from two GBM tumors. These cells were resistant to TMZ, had unmethylated MGMT, and expressed high levels of PLK1. Consistent with its role in suppressing GBM growth, DSF inhibited the expression of PLK1 in GBM cells. Likewise, PLK1 inhibition with siRNA, or small molecules (BI-2536 or BI-6727) blocked growth of TMZ resistant cells. Our studies suggest that DSF has the potential to be repurposed for treatment of refractory GBM. PMID:23047041

  3. Metformin and temozolomide act synergistically to inhibit growth of glioma cells and glioma stem cells in vitro and in vivo

    PubMed Central

    Yu, Zhiyun; Zhao, Gang; Xie, Guifang; Zhao, Liyan; Chen, Yong; Yu, Hongquan; Zhang, Zhonghua; Li, Cai; Li, Yunqian

    2015-01-01

    Glioblastoma (GBM) is the most frequent and aggressive brain tumor in adults. In spite of advances in diagnosis and therapy, the prognosis of patients with GBM has remained dismal. The fast recurrence and multi-drug resistance are some of the key challenges in combating brain tumors. Glioma stem cells (GSCs) which are considered the source of relapse and chemoresistance, the need for more effective therapeutic options is overwhelming. In our present work, we found that combined treatment with temozolomide (TMZ) and metformin (MET) synergistically inhibited proliferation and induced apoptosis in both glioma cells and GSCs. Combination of TMZ and MET significantly reduced the secondary gliosphere formation and expansion of GSCs. We first demonstrated that MET effectively inhibited the AKT activation induced by TMZ, and a combination of both drugs led to enhanced reduction of mTOR, 4EBP1 and S6K phosphorylation. In addition, the combination of the two drugs was accompanied with a powerful AMP-activated protein kinase (AMPK) activation, while this pathway is not determinant. Xenografts performed in nude mice demonstrate in vivo demonstrated that combined treatment significantly reduced tumor growth rates and prolonged median survival of tumor-bearing mice. In conclusion, TMZ in combination with MET synergistically inhibits the GSCs proliferation through downregulation of AKT-mTOR signaling pathway. The combined treatment of two drugs inhibits GSCs self-renewal capability and partly eliminates GSCs in vitro and in vivo. This combined treatment could be a promising option for patients with advanced GBM. PMID:26431379

  4. Brain Radiotherapy plus Concurrent Temozolomide versus Radiotherapy Alone for Patients with Brain Metastases: A Meta-Analysis

    PubMed Central

    Zhao, Qian; Qin, Qin; Sun, Jinglong; Han, Dan; Wang, Zhongtang; Teng, Junjie; Li, Baosheng

    2016-01-01

    Objective We performed a meta-analysis of randomized clinical trials to compare the efficacy of brain radiotherapy (RT) combined with temozolomide (TMZ) versus RT alone as first-line treatment for brain metastases (BM). Methods Medline, Embase, and Pubmed were used to search for relevant randomized controlled trials (RCTs). Two investigators reviewed the abstracts and independently rated the quality of trials and relevant data. The primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), objective response rate (ORR), and adverse events. Results Seven studies were selected from the literature search. RT plus TMZ produced significant improvement in ORR with odds ratio (OR) of 2.27 (95% CI, 1.29 to 4.00; P = 0.005) compared with RT alone. OS and PFS were not significantly different between the two arms (OS: HR, 1.00; P = 0.959; PFS: HR, 0.73; P = 0.232). However, the RT plus TMZ arm was associated with significantly more grade 3 to 4 nausea and thrombocytopenia. Conclusion Concomitant RT and TMZ, compared to RT alone, significantly increases ORR in patients with BM, but yields increased toxicity and fails to demonstrate a survival advantage. PMID:26930609

  5. Profile Analysis of Chemotherapy-induced Nausea and Vomiting in Patients Treated with Concomitant Temozolomide and Radiotherapy: Results of a Prospective Study

    PubMed Central

    MATSUDA, Masahide; YAMAMOTO, Tetsuya; ISHIKAWA, Eiichi; NAKAI, Kei; AKUTSU, Hiroyoshi; ONUMA, Kuniyuki; MATSUMURA, Akira

    2015-01-01

    Temozolomide (TMZ) as a concomitant and adjuvant chemotherapy to radiotherapy following maximal surgical resection is the established standard therapy for patients with newly diagnosed high-grade glioma. However, detailed analysis of chemotherapy-induced nausea and vomiting (CINV) associated with concomitant TMZ has not been sufficiently described. We prospectively analyzed the profile of CINV associated with concomitant TMZ. Eighteen consecutive patients with newly diagnosed high-grade glioma treated with concomitant chemoradiotherapy including TMZ were enrolled. CINV was recorded using a daily diary including nausea assessment, emetic episodes, degree of appetite suppression, and antiemetic medication use. The observed incidence rates of all grade nausea, moderate/severe (CTC grade 2, 3) nausea, emetic episodes, and appetite suppression for the overall period were 89%, 39%, 39%, and 83%, respectively. Moderate/severe nausea and severe (CTC grade 3) appetite suppression were frequently observed during the delayed phase of the treatment. Emetic episodes and moderate/severe nausea were significantly correlated with female gender. Moderate/severe nausea and severe appetite suppression were significantly correlated with low lymphocyte counts before chemoradiotherapy. For CINV associated with concomitant TMZ, enhanced antiemetic therapy focused on the delayed phase of the treatment will likely be beneficial, especially in female patients with a low lymphocyte count before chemoradiotherapy. PMID:26345664

  6. Nanoparticle-Delivered Antisense MicroRNA-21 Enhances the Effects of Temozolomide on Glioblastoma Cells.

    PubMed

    Ananta, Jeyarama S; Paulmurugan, Ramasamy; Massoud, Tarik F

    2015-12-01

    Glioblastoma (GBM) generally exhibits high IC50 values for its standard drug treatment, temozolomide (TMZ). MicroRNA-21 (miR-21) is an oncomiR overexpressed in GBM, thus controlling important aspects of glioma biology. We hypothesized that PLGA nanoparticles carrying antisense miR-21 to glioblastoma cells might beneficially knock down endogenous miR-21 prior to TMZ treatment. PLGA nanoparticles encapsulating antisense miR-21 were effective in intracellular delivery and sustained silencing (p < 0.01) of miR-21 function in U87 MG, LN229, and T98G cells. Prior antisense miR-21 delivery significantly reduced the number of viable cells (p < 0.001), and increased (1.6-fold) cell cycle arrest at G2/M phase upon TMZ treatment in U87 MG cells. There was overexpression of the miR-21 target genes PTEN (by 67%) and caspase-3 (by 15%) upon cotreatment. This promising PLGA nanoparticle-based platform for antisense miR-21 delivery to GBM is an effective cotherapeutic strategy in cell culture, warranting the need for further studies prior to future clinical translation. PMID:26559642

  7. BMS-536924, an ATP-competitive IGF-1R/IR inhibitor, decreases viability and migration of temozolomide-resistant glioma cells in vitro and suppresses tumor growth in vivo.

    PubMed

    Zhou, Qiao

    2015-01-01

    Glioma is the most common type of primary brain tumor. Despite the combination of surgery, chemotherapy, and radiotherapy, the median survival duration of patients with malignant glioma is still very short. Temozolomide (TMZ) is the primary and most promising therapeutic drug for glioma; however, it is easy to develop acquired resistance during treatment. Activation of receptor tyrosine kinases (RTKs) has been identified to be involved in the acquisition of resistance toward many anticancer drugs. So inhibition of RTKs might be a promising therapeutic strategy for overcoming or attenuating acquired drug resistance. Here, we have investigated the anticancer activities of BMS-536924, an ATP-competitive IGF-1R/IR inhibitor in glioma, especially TMZ-resistant glioma, both in vitro and in vivo. We found that BMS-536924 could effectively reduce viability of both TMZ-sensitive and -resistant glioma cells. BMS-536924 induced dramatic apoptosis in TMZ-resistant cells, and it also dramatically inhibited migration of TMZ-resistant cells. Importantly, BMS-536924 significantly suppressed glioma tumor growth in vivo. This is the first report on anticancer activity of BMS-536924 in glioma. BMS-536924 is a promising compound in the therapy of glioma, especially of TMZ-resistant glioma, which might shed new light on glioma therapy.

  8. Inhibition of DNA-repair genes Ercc1 and Mgmt enhances temozolomide efficacy in gliomas treatment: a pre-clinical study.

    PubMed

    Boccard, Sandra G; Marand, Sandie V; Geraci, Sandra; Pycroft, Laurie; Berger, François R; Pelletier, Laurent A

    2015-10-01

    Gliomas are the most common primary brain tumors. To date, therapies do not allow curing patients, and glioblastomas (GBMs) are associated with remarkably poor prognosis. This situation is at least partly due to intrinsic or acquired resistance to treatment, especially to chemotherapy. In 2005, temozolomide (TMZ) has become the first chemotherapeutic drug validated for GBM. Nevertheless TMZ efficacy depends on Mgmt status. While the methylation of Mgmt promoter was considered so far as a prognostic marker, its targeting is becoming an effective therapeutic opportunity. Thus, arrival of both TMZ and Mgmt illustrated that considerable progress can still be realized by optimizing adjuvant chemotherapy. A part of this progress could be accomplished in the future by overcoming residual resistance. The aim of the present study was to investigate the involvement of a set of other DNA-repair genes in glioma resistance to temozolomide. We focused on DNA-repair genes located in the commonly deleted chromosomal region in oligodendroglioma (1p/19q) highly correlated with patient response to chemotherapy. We measured effects of inhibition of ten DNA-repair genes expression using siRNAs on astrocytoma cell response to cisplatin (CDDP) and TMZ. SiRNAs targeting ercc1, ercc2, mutyh, and pnkp significantly sensitized cells to chemotherapy, increasing cell death by up to 25%. In vivo we observed a decrease of subcutaneous glioma tumor growth after injection of siRNA in conjunction with absorption of TMZ. We demonstrated in this pre-clinical study that targeting of DNA-repair genes such as Ercc1 could be used as an adjuvant chemosensitization treatment, similarly to Mgmt inhibition. PMID:26336131

  9. Inhibition of DNA-repair genes Ercc1 and Mgmt enhances temozolomide efficacy in gliomas treatment: a pre-clinical study

    PubMed Central

    Boccard, Sandra G.; Marand, Sandie V.; Geraci, Sandra; Pycroft, Laurie; Berger, François R.; Pelletier, Laurent A.

    2015-01-01

    Gliomas are the most common primary brain tumors. To date, therapies do not allow curing patients, and glioblastomas (GBMs) are associated with remarkably poor prognosis. This situation is at least partly due to intrinsic or acquired resistance to treatment, especially to chemotherapy. In 2005, temozolomide (TMZ) has become the first chemotherapeutic drug validated for GBM. Nevertheless TMZ efficacy depends on Mgmt status. While the methylation of Mgmt promoter was considered so far as a prognostic marker, its targeting is becoming an effective therapeutic opportunity. Thus, arrival of both TMZ and Mgmt illustrated that considerable progress can still be realized by optimizing adjuvant chemotherapy. A part of this progress could be accomplished in the future by overcoming residual resistance. The aim of the present study was to investigate the involvement of a set of other DNA-repair genes in glioma resistance to temozolomide. We focused on DNA-repair genes located in the commonly deleted chromosomal region in oligodendroglioma (1p/19q) highly correlated with patient response to chemotherapy. We measured effects of inhibition of ten DNA-repair genes expression using siRNAs on astrocytoma cell response to cisplatin (CDDP) and TMZ. SiRNAs targeting ercc1, ercc2, mutyh, and pnkp significantly sensitized cells to chemotherapy, increasing cell death by up to 25%. In vivo we observed a decrease of subcutaneous glioma tumor growth after injection of siRNA in conjunction with absorption of TMZ. We demonstrated in this pre-clinical study that targeting of DNA-repair genes such as Ercc1 could be used as an adjuvant chemosensitization treatment, similarly to Mgmt inhibition. PMID:26336131

  10. Phase I Trial of Hypofractionated Intensity-Modulated Radiotherapy With Temozolomide Chemotherapy for Patients With Newly Diagnosed Glioblastoma Multiforme

    SciTech Connect

    Chen Changhu; Damek, Denise; Gaspar, Laurie E.; Waziri, Allen; Lillehei, Kevin; Kleinschmidt-DeMasters, B.K.; Robischon, Monica; Stuhr, Kelly; Rusthoven, Kyle E.; Kavanagh, Brian D.

    2011-11-15

    Purpose: To determine the maximal tolerated biologic dose intensification of radiotherapy using fractional dose escalation with temozolomide (TMZ) chemotherapy in patients with newly diagnosed glioblastoma multiforme. Methods and Materials: Patients with newly diagnosed glioblastoma multiforme after biopsy or resection and with adequate performance status, bone marrow, and organ function were eligible. The patients underwent postoperative intensity-modulated radiotherapy (IMRT) with concurrent and adjuvant TMZ. All patients received a total dose of 60 Gy to the surgical cavity and residual tumor, with a 5-mm margin. IMRT biologic dose intensification was achieved by escalating from 3 Gy/fraction (Level 1) to 6 Gy/fraction (Level 4) in 1-Gy increments. Concurrent TMZ was given at 75 mg/m{sup 2}/d for 28 consecutive days. Adjuvant TMZ was given at 150-200 mg/m{sup 2}/d for 5 days every 28 days. Dose-limiting toxicity was defined as any Common Terminology Criteria for Adverse Events, version 3, Grade 3-4 nonhematologic toxicity, excluding Grade 3 fatigue, nausea, and vomiting. A standard 3+3 Phase I design was used. Results: A total of 16 patients were accrued (12 men and 4 women, median age, 69 years; range, 34-84. The median Karnofsky performance status was 80 (range, 60-90). Of the 16 patients, 3 each were treated at Levels 1 and 2, 4 at Level 3, and 6 at Level 4. All patients received IMRT and concurrent TMZ according to the protocol, except for 1 patient, who received 14 days of concurrent TMZ. The median number of adjuvant TMZ cycles was 7.5 (range, 0-12). The median survival was 16.2 months (range, 3-33). One patient experienced vision loss in the left eye 7 months after IMRT. Four patients underwent repeat surgery for suspected tumor recurrence 6-12 months after IMRT; 3 had radionecrosis. Conclusions: The maximal tolerated IMRT fraction size was not reached in our study. Our results have shown that 60 Gy IMRT delivered in 6-Gy fractions within 2 weeks with

  11. Quality of life in low-grade glioma patients receiving temozolomide

    PubMed Central

    Liu, Raymond; Solheim, Karla; Polley, Mei-Yin; Lamborn, Kathleen R.; Page, Margaretta; Fedoroff, Anne; Rabbitt, Jane; Butowski, Nicholas; Prados, Michael; Chang, Susan M.

    2009-01-01

    The purpose of this study was to describe the quality of life (QOL) of low-grade glioma (LGG) patients at baseline prior to chemotherapy and through 12 cycles of temozolomide (TMZ) chemotherapy. Patients with histologically confirmed LGG with only prior surgery were given TMZ for 12 cycles. QOL assessments by the Functional Assessment of Cancer Therapy–Brain (FACT-Br) were obtained at baseline prior to chemotherapy and at 2-month intervals while receiving TMZ. Patients with LGG at baseline prior to chemotherapy had higher reported social well-being scores (mean difference = 5.0; p < 0.01) but had lower reported emotional well-being scores (mean difference = 2.2; p < 0.01) compared to a normal population. Compared to patients with left hemisphere tumors, patients with right hemisphere tumors reported higher physical well-being scores (p = 0.01): 44% could not drive, 26% did not feel independent, and 26% were afraid of having a seizure. Difficulty with work was noted in 24%. Mean change scores at each chemotherapy cycle compared to baseline for all QOL subscales showed either no significant change or were significantly positive (p < 0.01). Patients with LGG on TMZ at baseline prior to chemotherapy reported QOL comparable to a normal population with the exception of social and emotional well-being, and those with right hemisphere tumors reported higher physical well-being scores compared to those with left hemisphere tumors. While remaining on therapy, LGG patients were able to maintain their QOL in all realms. LGG patients’ QOL may be further improved by addressing their emotional well-being and their loss of independence in terms of driving or working. PMID:18713953

  12. Inhibition of MMP14 potentiates the therapeutic effect of temozolomide and radiation in gliomas

    PubMed Central

    Ulasov, Ilya; Thaci, Bart; Sarvaiya, Purvaba; Yi, Ruiyang; Guo, Donna; Auffinger, Brenda; Pytel, Peter; Zhang, Lingjiao; Kim, Chung Kwon; Borovjagin, Anton; Dey, Mahua; Han, Yu; Baryshnikov, Anatoly Y; Lesniak, Maciej S

    2013-01-01

    Abstract Metalloproteinases are membrane-bound proteins that play a role in the cellular responses to antiglioma therapy. Previously, it has been shown that treatment of glioma cells with temozolomide (TMZ) and radiation (XRT) induces the expression of metalloproteinase 14 (MMP14). To investigate the role of MMP14 in gliomagenesis, we used several chemical inhibitors which affect MMP14 expression. Of all the inhibitors tested, we found that Marimastat not only inhibits the expression of MMP14 in U87 and U251 glioma cells, but also induces cell cycle arrest. To determine the relationship between MMP14 inhibition and alteration of the cell cycle, we used an RNAi technique. Genetic knockdown of MMP14 in U87 and U251 glioma cells induced G2/M arrest and decreased proliferation. Mechanistically, we show that TMZ and XRT regulated expression of MMP14 in clinical samples and in vitro models through downregulation of microRNA374. In vivo genetic knockdown of MMP14 significantly decreased tumor growth of glioma xenografts and improved survival of glioma-bearing mice. Moreover, the combination of MMP14 silencing with TMZ and XRT significantly improved the survival of glioma-bearing mice compared to a single modality treatment group. Therefore, we show that the inhibition of MMP14 sensitizes tumor cells to TMZ and XRT and could be used as a future strategy for antiglioma therapy. Glioblastoma remains an incurable form of brain cancer. In this manuscript, we show that inhibition of MMP14 can potentiate the efficacy of current standard of care which includes chemo- and radiotherapy. PMID:24156018

  13. Erythropoietin Augments Survival of Glioma Cells After Radiation and Temozolomide

    SciTech Connect

    Hassouna, Imam; Sperling, Swetlana; Kim, Ella; Schulz-Schaeffer, Walter; Rave-Fraenk, Margret; Hasselblatt, Martin; Jelkmann, Wolfgang; Giese, Alf; Ehrenreich, Hannelore

    2008-11-01

    Purpose: Despite beneficial effects of irradiation/chemotherapy on survival of glioblastoma (GBM) patients, collateral damage to intact neural tissue leads to 'radiochemobrain' and reduced quality of life in survivors. For prophylactic neuroprotection, erythropoietin (EPO) is a promising candidate, provided that concerns regarding potential tumor promoting effects are alleviated. Methods and Materials: Human GBM-derived cell lines U87, G44, G112, and the gliosarcoma-derived line G28 were treated with EPO, with and without combinations of irradiation or temozolomide (TMZ). Responsiveness of glioma cells to EPO was measured by cell migration from spheroids, cell proliferation, and clonogenic survival. Implantation of U87 cells into brains of nude mice, followed 5 days later by EPO treatment (5,000 U/kg intraperitoneal every other day for 2 weeks) should reveal effects of EPO on tumor growth in vivo. Reverse transcriptase-polymerase chain reaction was performed for EPOR, HIF-1{alpha}, and epidermal growth factor receptor (EGFR)vIII in cell lines and 22 human GBM specimens. Results: EPO did not modulate basal glioma cell migration and stimulated proliferation in only one of four cell lines. Importantly, EPO did not enhance tumor growth in mouse brains. Preincubation of glioma cells with EPO for 3 h, followed by irradiation and TMZ for another 24 h, resulted in protection against chemoradiation-induced cytotoxicity in three cell lines. Conversely, EPO induced a dose-dependent decrease in survival of G28 gliosarcoma cells. In GBM specimens, expression of HIF-1{alpha} correlated positively with expression of EPOR and EGFRvIII. EPOR and EGFRvIII expression did not correlate. Conclusions: EPO is unlikely to appreciably influence basal glioma growth. However, concomitant use of EPO with irradiation/chemotherapy in GBM patients is not advisable.

  14. Impact of 1p/19q Codeletion and Histology on Outcomes of Anaplastic Gliomas Treated With Radiation Therapy and Temozolomide

    SciTech Connect

    Speirs, Christina K.; Simpson, Joseph R.; Robinson, Clifford G.; DeWees, Todd A.; Tran, David D.; Linette, Gerry; Chicoine, Michael R.; Dacey, Ralph G.; Rich, Keith M.; Dowling, Joshua L.; Leuthardt, Eric C.; Zipfel, Gregory J.; Kim, Albert H.; Huang, Jiayi

    2015-02-01

    Purpose: Anaplastic gliomas represent a heterogeneous group of primary high-grade brain tumors, and the optimal postoperative treatment remains controversial. In this report, we present our institutional data on the clinical outcomes of radiation therapy (RT) plus temozolomide (RT + TMZ) for anaplastic gliomas, stratified by histology and 1p/19q codeletion. Methods and Materials: A single-institution retrospective review was conducted of patients with supratentorial anaplastic oligodendroglioma (AO), mixed anaplastic oligoastrocytoma (AOA), and anaplastic astrocytoma (AA). After surgery, RT was delivered at a median total dose of 60 Gy (range, 31.6-63 Gy) in daily fractions. All patients received standard concurrent TMZ, with or without adjuvant TMZ. Histological/molecular subtypes were defined as codeleted AO/AOA, non-codeleted AO/AOA, and AA. Results: From 2000 to 2012, 111 cases met study criteria and were evaluable. Codeleted AO/AOA had superior overall survival (OS) to non-codeleted AO/AOA (91% vs 68% at 5 years, respectively, P=.02), whereas progression-free survival (PFS) was not significantly different (70% vs 46% at 5 years, respectively, P=.10). AA had inferior OS to non-codeleted AO/AOA (37% vs 68% at 5 years, respectively, P=.007) and inferior PFS (27% vs 46%, respectively, P=.03). On multivariate analysis, age, performance status, and histological or molecular subtype were independent predictors for both PFS and OS. Compared to historical controls, RT + TMZ provided comparable OS to RT with procarbazine, lomustine, and vincristine (RT + PCV) for codeleted AO/AOA, superior OS to RT alone for non-codeleted AO/AOA, and similar OS to RT alone for AA. Conclusions: RT + TMZ may be a promising treatment for both codeleted and non-codeleted AO/AOA, but its role for AA remains unclear.

  15. The Effect of Chemoradiotherapy with SRC Tyrosine Kinase Inhibitor, PP2 and Temozolomide on Malignant Glioma Cells In Vitro and In Vivo

    PubMed Central

    Eom, Keun-Yong; Cho, Bong Jun; Choi, Eun Jung; Kim, Jin-Ho; Chie, Eui Kyu; Wu, Hong-Gyun; Kim, Il Han; Paek, Sun Ha; Kim, Jae-Sung; Kim, In Ah

    2016-01-01

    Purpose We investigated the effect of chemoradiotherapy with PP2 and temozolomide (TMZ) on malignant glioma cells using clonogenic assays and in vivo brain tumor model. Materials and Methods The effect of PP2 on radiosensitivity of U251 and T98G cells was investigated using clonogenic assays. The expression of E-cadherin, matrix metalloproteinases 2 (MMP2), Ephrin type-A receptor 2 (EphA2), and vascular endothelial growth factor (VEGF) was measured by Western blotting and an accumulation of γH2AX foci 6 hours after radiotherapy was measured after PP2 treatment. The effect of PP2 on migration, invasion, and vasculogenic mimicry formation (VMF) of U251 cells was evaluated. In an orthotopical brain tumor model with U251 cells, PP2 was injected intraperitoneally with or without oral TMZ before, during and after whole brain radiotherapy. Bioluminescence images were taken to visualize in vivo tumors and immunohistochemical staining of VEGF, CD31, EphA2, and hypoxia-inducible factor 1a was performed. Results PP2 increased radiosensitivity of U251 and T98G cells without decreasing survival of normal human astrocytes. Chemoradiotherapy with PP2 and TMZ resulted in increased accumulation of γH2AX foci. PP2 induced overexpression of E-cadherin and suppression of MMP2, VEGF, and EphA2. PP2 also compromised invasion, migration, and VMF of U251 cells. In brain tumors, chemoradiotherapy with PP2 and TMZ decreased tumor volume best, but not statistically significantly compared with chemoradiotherapy with TMZ. The expression of VEGF and CD31 was suppressed in PP2-treated tumors. Conclusion PP2 enhances radiosensitivity of malignant glioma cells and suppresses invasion and migration of U251 cells. Chemoradiotherapy with PP2 and TMZ resulted in non-significant tumor volume decrease. PMID:26044161

  16. Apoptosis induced by temozolomide and nimustine in glioblastoma cells is supported by JNK/c-Jun-mediated induction of the BH3-only protein BIM.

    PubMed

    Tomicic, Maja T; Meise, Ruth; Aasland, Dorthe; Berte, Nancy; Kitzinger, Rebekka; Krämer, Oliver H; Kaina, Bernd; Christmann, Markus

    2015-10-20

    The outcome of cancer therapy strongly depends on the complex network of cell signaling pathways, including transcription factor activation following drug exposure. Here we assessed whether and how the MAP kinase (MAPK) cascade and its downstream target, the transcription factor AP-1, influence the sensitivity of malignant glioma cells to the anticancer drugs temozolomide (TMZ) and nimustine (ACNU). Both drugs induce apoptosis in glioma cells at late times following treatment. Activation of the MAPK cascade precedes apoptosis, as shown by phosphorylation of Jun kinase (JNK) and c-Jun, a main component of AP-1. Pharmacological inhibition and siRNA mediated knockdown of JNK and c-Jun reduced the level of apoptosis in LN-229 glioma cells treated with TMZ or ACNU. Analyzing the underlying molecular mechanism, we identified the pro-apoptotic gene BIM as a critical target of AP-1, which is upregulated following TMZ and ACNU. Importantly, shRNA mediated downregulation of BIM in the malignant glioma cell lines LN-229 and U87MG led to an attenuated cleavage of caspase-9 and, consequently, reduced the level of apoptosis following TMZ and ACNU treatment. Overall, we identified JNK/c-Jun activation and BIM induction as a late pro-apoptotic response of glioma cells treated with alkylating anticancer drugs. PMID:26418950

  17. Disulfiram, a drug widely used to control alcoholism, suppresses the self-renewal of glioblastoma and over-rides resistance to temozolomide.

    PubMed

    Triscott, Joanna; Lee, Cathy; Hu, Kaiji; Fotovati, Abbas; Berns, Rachel; Pambid, Mary; Luk, Margaret; Kast, Richard E; Kong, Esther; Toyota, Eric; Yip, Stephen; Toyota, Brian; Dunn, Sandra E

    2012-10-01

    Glioblastomas (GBM) are associated with high rates of relapse. These brain tumors are often resistant to chemotherapies like temozolomide (TMZ) and there are very few treatment options available to patients. We recently reported that polo-like kinase-1 (PLK1) is associated with the proliferative subtype of GBM; which has the worst prognosis. In this study, we addressed the potential of repurposing disulfiram (DSF), a drug widely used to control alcoholism for the past six decades. DSF has good safety profiles and penetrates the blood-brain barrier. Here we report that DSF inhibited the growth of TMZ resistant GBM cells, (IC90=100 nM), but did not affect normal human astrocytes. At similar DSF concentrations, self-renewal was blocked by ~100% using neurosphere growth assays. Likewise the drug completely inhibited the self-renewal of the BT74 and GBM4 primary cell lines. Additionally, DSF suppressed growth and self-renewal of primary cells from two GBM tumors.These cells were resistant to TMZ, had unmethylated MGMT, and expressed high levels of PLK1. Consistent with its role in suppressing GBM growth, DSF inhibited the expression of PLK1 in GBM cells. Likewise, PLK1 inhibition with siRNA, or small molecules (BI-2536 or BI-6727) blocked growth of TMZ resistant cells. Our studies suggest that DSF has the potential to be repurposed for treatment of refractory GBM. PMID:23047041

  18. Apoptosis induced by temozolomide and nimustine in glioblastoma cells is supported by JNK/c-Jun-mediated induction of the BH3-only protein BIM

    PubMed Central

    Aasland, Dorthe; Berte, Nancy; Kitzinger, Rebekka; Krämer, Oliver H.; Kaina, Bernd; Christmann, Markus

    2015-01-01

    The outcome of cancer therapy strongly depends on the complex network of cell signaling pathways, including transcription factor activation following drug exposure. Here we assessed whether and how the MAP kinase (MAPK) cascade and its downstream target, the transcription factor AP-1, influence the sensitivity of malignant glioma cells to the anticancer drugs temozolomide (TMZ) and nimustine (ACNU). Both drugs induce apoptosis in glioma cells at late times following treatment. Activation of the MAPK cascade precedes apoptosis, as shown by phosphorylation of Jun kinase (JNK) and c-Jun, a main component of AP-1. Pharmacological inhibition and siRNA mediated knockdown of JNK and c-Jun reduced the level of apoptosis in LN-229 glioma cells treated with TMZ or ACNU. Analyzing the underlying molecular mechanism, we identified the pro-apoptotic gene BIM as a critical target of AP-1, which is upregulated following TMZ and ACNU. Importantly, shRNA mediated downregulation of BIM in the malignant glioma cell lines LN-229 and U87MG led to an attenuated cleavage of caspase-9 and, consequently, reduced the level of apoptosis following TMZ and ACNU treatment. Overall, we identified JNK/c-Jun activation and BIM induction as a late pro-apoptotic response of glioma cells treated with alkylating anticancer drugs. PMID:26418950

  19. The role of temozolomide in the management of patients with newly diagnosed anaplastic astrocytoma: a comparison of survival in the era prior to and following the availability of temozolomide

    PubMed Central

    Abuali, Inas; Ye, Xiaobu; Lu, Yao; Grossman, Stuart A.

    2016-01-01

    Adding temozolomide (TMZ) to radiation for patients with newly-diagnosed anaplastic astrocytomas (AAs) is common clinical practice despite the lack of prospective studies demonstrating a survival advantage. Two retrospective studies, each with methodologic limitations, provide conflicting advice regarding treatment. This single-institution retrospective study was conducted to determine survival trends in patients with AA. All patients ≥18 years with newly-diagnosed AA treated at Johns Hopkins from 1995 to 2012 were included. As we incorporated TMZ into high-grade glioma treatment regimens in 2004, patients were divided into pre-2004 and post-2004 groups for analysis. Clinical, radiographic, and pathologic data were collected. Median overall survival (OS) was calculated using Kaplan–Meier estimates. A total of 196 patients were identified; 74 pre-2004 and 122 post-2004; mean age 47 ± 15 years; 57 % male; 87 % white, 69 % surgical debulking. Mean RT dose 5676 + 746 cGy; duration of concurrent chemoradiation 5.8 ± 0.8 weeks; and mean adjuvant chemotherapy 4.3 + 2.8 cycles. Baseline prognostic factors did not differ between groups. Chemotherapy was administered to 12 % of patients pre-2004 (TMZ = 1, procarbazine, lomustine and vincristine = 2, carmustine wafer = 6) and 94 % post-2004 (TMZ in all, p < 0.001). Median OS was 32 months (95 % CI 23–43). Survival was longer in the post-2004 cohort (37 mo, 24–64) than pre-2004 (27 mo, 19–40; HR 0.75, 0.53–1.06, p = 0.11). Multivariate analysis controlling for age, Karnofsky performance status, and extent of resection revealed a 36 % reduced risk of death (HR 0.64, 0.44–0.91, p = 0.015) in patients treated post-2004. This retrospective review found survival in newly diagnosed patients with AA improved with the addition of temozolomide to standard radiation. Until prospective randomized phase III data are available, these data support the practice of incorporating TMZ in the management of newly-diagnosed AA

  20. Induction of microRNA-146a is involved in curcumin-mediated enhancement of temozolomide cytotoxicity against human glioblastoma.

    PubMed

    Wu, Hao; Liu, Qiang; Cai, Tao; Chen, Yu-Dan; Wang, Zhi-Fei

    2015-10-01

    MicroRNA (miR)-146a is a negative regulator of nuclear factor-κB (NF-κB) signaling that affects tumor growth and survival. The present study was undertaken to determine whether the cytotoxicity of curcumin (diferuloylmethane), a natural polyphenolic compound isolated from turmeric (Curcuma longa Linn), in glioblastoma cells is mediated through upregulation of miR‑146a. Human U‑87 MG glioblastoma cells were treated with curcumin and temozolomide (TMZ) alone or in combination, and cell proliferation and apoptosis were assessed. The involvement of miR‑146a and NF‑κB signaling in curcumin‑mediated chemosensitization was explored. Curcumin exposure led to upregulation of miR‑146a in U‑87 MG cells. Combined curcumin and TMZ treatment significantly (P<0.05) inhibited U‑87 MG cell proliferation and induced apoptotic death, compared with each alone. Notably, curcumin‑mediated enhancement of TMZ‑induced apoptosis was blocked by depletion of miR‑146a. By contrast, miR‑146a overexpression enhanced apoptosis and suppressed NF‑κB activation in TMZ‑treated cells. Additionally, pharmacological inhibition of NF‑κB signaling significantly increased TMZ‑induced apoptosis. To the best of our knowledge, the present study provides the first evidence that upregulation of miR‑146a and inactivation of NF‑κB signaling mediates the sensitization of human glioblastoma cells to TMZ-induced apoptosis by curcumin. PMID:26239619

  1. Low c-Met expression levels are prognostic for and predict the benefits of temozolomide chemotherapy in malignant gliomas

    PubMed Central

    Li, Ming-Yang; Yang, Pei; Liu, Yan-Wei; Zhang, Chuan-Bao; Wang, Kuan-Yu; Wang, Yin-Yan; Yao, Kun; Zhang, Wei; Qiu, Xiao-Guang; Li, Wen-Bin; Peng, Xiao-Xia; Wang, Yong-Zhi; Jiang, Tao

    2016-01-01

    Aberrant c-Met has been implicated in the development of many cancers. The objective of this study was to identify an unfavorable prognostic marker that might guide decisions regarding clinical treatment strategies for high-grade gliomas. C-Met expression was measured using immunohistochemistry in 783 gliomas, and we further analyzed c-Met mRNA levels using the Agilent Whole Genome mRNA Microarray in 286 frozen samples. In vitro, we performed cell migration and invasion assays. Cell sensitivity to temozolomide (TMZ) chemotherapy was determined using MTT assays. Both mRNA and protein levels of c-Met were significantly associated with tumor grade progression and inversely correlated with overall and progression-free survival in high-grade gliomas (all P < 0.0001). These findings were nearly consistent at the mRNA level across 3 independent cohorts. Multivariable analysis indicated that c-Met was an independent prognostic marker after adjusting for age, preoperative Karnofsky Performance Status (KPS) score, the extent of resection, radiotherapy, TMZ chemotherapy, and O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status. Further analysis in vitro revealed that downregulating the expression of c-Met dramatically inhibited cell migration and invasion capacities, enhanced sensitivity to TMZ chemotherapy in H4 and U87 glioma cells. Our results suggest that c-Met may serve as a potential predictive maker for clinical decision making. PMID:26879272

  2. Interactions of Nucleic Acid Bases with Temozolomide. Stacked, Perpendicular, and Coplanar Heterodimers.

    PubMed

    Kasende, Okuma Emile; Nziko, Vincent de Paul N; Scheiner, Steve

    2016-09-01

    Temozolomide (TMZ) was paired with each of the five nucleic acid bases, and the potential energy surface searched for all minima, in the context of dispersion-corrected density functional theory and MP2 methods. Three types of arrangements were observed, with competitive stabilities. Coplanar H-bonding structures, reminiscent of Watson-Crick base pairs were typically the lowest in energy, albeit by a small amount. Also very stable were perpendicular arrangements that included one or more H-bonds. The two monomers were stacked approximately parallel to one another in the third category, some of which contained weak and distorted H-bonds. Dispersion was found to be a dominating attractive force, largest for the stacked structures, and smallest for the coplanar dimers.

  3. A complex mechanism for HDGF-mediated cell growth, migration, invasion, and TMZ chemosensitivity in glioma.

    PubMed

    Song, Ye; Hu, Zheng; Long, Hao; Peng, Yuping; Zhang, Xi'an; Que, Tianshi; Zheng, Shihao; Li, Zhiyong; Wang, Gang; Yi, Liu; Liu, Zhen; Fang, Weiyi; Qi, Songtao

    2014-09-01

    HDGF is overexpressed in gliomas as compared to normal brain. We therefore analyzed the molecular mechanisms of HDGF action in gliomas. HDGF was downregulated in normal brain tissue as compared to glioma specimens at both the mRNA and the protein levels. In glioma samples, increased HDGF expression was associated with disease progression. Knocking down HDGF expression not only significantly decreased cellular proliferation, migration, invasion, and tumorigenesis, but also markedly enhanced TMZ-induced cytotoxicity and apoptosis in glioma cells. Mechanistic analyses revealed that CCND1, c-myc, and TGF-β were downregulated after stable HDGF knockdown in the U251 and U87 glioma cells. HDGF knockdown restored E-cadherin expression and suppressed mesenchymal cell markers such as vimentin, β-catenin, and N-cadherin. The expression of cleaved caspase-3 increased, while Bcl-2 decreased in each cell line following treatment with shHDGF and TMZ, as compared to TMZ alone. Furthermore, RNAi-based knockdown study revealed that HDGF is probably involved in the activation of both the PI3K/Akt and the TGF-β signaling pathways. Together, our data suggested that HDGF regulates glioma cell growth, apoptosis and epithelial-mesenchymal transition (EMT) probably through the Akt and the TGF-β signaling pathways. These results provide evidence that targeting HDGF or its downstream targets may lead to novel therapies for gliomas.

  4. Does Early Postsurgical Temozolomide Plus Concomitant Radiochemotherapy Regimen Have Any Benefit in Newly-diagnosed Glioblastoma Patients? A Multi-center, Randomized, Parallel, Open-label, Phase II Clinical Trial

    PubMed Central

    Mao, Ying; Yao, Yu; Zhang, Li-Wei; Lu, Yi-Cheng; Chen, Zhong-Ping; Zhang, Jian-Min; Qi, Song-Tao; You, Chao; Wang, Ren-Zhi; Yang, Shu-Yuan; Zhang, Xiang; Wang, Ji-Sheng; Chen, Ju-Xiang; Yang, Qun-Ying; Shen, Hong; Li, Zhi-Yong; Wang, Xiang; Ma, Wen-Bin; Yang, Xue-Jun; Zhen, Hai-Ning; Zhou, Liang-Fu

    2015-01-01

    Background: The radiochemotherapy regimen concomitantly employing temozolomide (TMZ) chemotherapy and radiotherapy (RT) 4 weeks after surgery, followed by 6 cycles of TMZ is a common treatment for glioblastoma (GBM). However, its median overall survival (OS) is only 14.6 months. This study was to explore the effectiveness and safety of early TMZ chemotherapy between surgery and chemoradiotherapy plus the standard concomitant radiochemotherapy regimen. Methods: A randomized, parallel group, open-label study of 99 newly diagnosed GBM patients was conducted at 10 independent Chinese neurosurgical departments from June 2008 to June 2012. Patients were treated with concomitant radiochemotherapy regimen plus early postsurgical temozolomide (early TMZ group) or standard concomitant radiochemotherapy regimen (control group). Overall response was assessed based on objective tumor assessments, administration of corticosteroid and neurological status test. Hematological, biochemical, laboratory, adverse event (AE), and neurological condition were measured for 24 months of follow-up. The primary efficacy endpoint of this study was overall survival (OS). The secondary endpoint was progression free survival (PFS). Results: The median OS time in the early TMZ group was 17.6 months, compared with 13.2 months in the control group (log-rank test P = 0.021). In addition, the OS rate in the early TMZ group was higher at 6, 12, and 18 months than in the control group, respectively (P < 0.05). The median PFS time was 8.7 months in the early TMZ group and 10.4 months in the control group (log-rank test P = 0.695). AEs occurred in 29 (55.8%) and 31(73.8%) patients respectively in early and control groups, including nausea (15.4% vs. 33.3%), vomiting (7.7% vs. 28.6%), fever (7.7% vs. 11.9%), and headache (3.8% vs. 23.8%). Only 30.8% and 33.3% were drug-related, respectively. Conclusions: Addition of TMZ chemotherapy in the early break of the standard concomitant radiochemotherapy regimen

  5. North Central Cancer Treatment Group Phase I Trial N057K of Everolimus (RAD001) and Temozolomide in Combination With Radiation Therapy in Patients With Newly Diagnosed Glioblastoma Multiforme

    SciTech Connect

    Sarkaria, Jann N.; Galanis, Evanthia; Wu Wenting; Peller, Patrick J.; Giannini, Caterina; Brown, Paul D.; Uhm, Joon H.; McGraw, Steven; Jaeckle, Kurt A.; Buckner, Jan C.

    2011-10-01

    Background: The mammalian target of rapamycin (mTOR) functions within the PI3K/Akt signaling pathway as a critical modulator of cell survival. On the basis of promising preclinical data, the safety and tolerability of therapy with the mTOR inhibitor RAD001 in combination with radiation (RT) and temozolomide (TMZ) was evaluated in this Phase I study. Methods and Materials: All patients received weekly oral RAD001 in combination with standard chemoradiotherapy, followed by RAD001 in combination with standard adjuvant temozolomide. RAD001 was dose escalated in cohorts of 6 patients. Dose-limiting toxicities were defined during RAD001 combination therapy with TMZ/RT. Results: Eighteen patients were enrolled, with a median follow-up of 8.4 months. Combined therapy was well tolerated at all dose levels, with 1 patient on each dose level experiencing a dose-limiting toxicity: Grade 3 fatigue, Grade 4 hematologic toxicity, and Grade 4 liver dysfunction. Throughout therapy, there were no Grade 5 events, 3 patients experienced Grade 4 toxicities, and 6 patients had Grade 3 toxicities attributable to treatment. On the basis of these results, the recommended Phase II dosage currently being tested is RAD001 70 mg/week in combination with standard chemoradiotherapy. Fluorodeoxyglucose (FDG) positron emission tomography scans also were obtained at baseline and after the second RAD001 dose before the initiation of TMZ/RT; the change in FDG uptake between scans was calculated for each patient. Fourteen patients had stable metabolic disease, and 4 patients had a partial metabolic response. Conclusions: RAD001 in combination with RT/TMZ and adjuvant TMZ was reasonably well tolerated. Changes in tumor metabolism can be detected by FDG positron emission tomography in a subset of patients within days of initiating RAD001 therapy.

  6. Long-Term Survival in Patients with Metastatic Melanoma Treated with DTIC or Temozolomide

    PubMed Central

    Kim, Christina; Lee, Christopher W.; Kovacic, Laurel; Shah, Amil; Klasa, Richard

    2010-01-01

    Background. Patients with metastatic melanoma typically have a poor outcome; however, a small proportion of patients achieve long-term survival (LTS). It is unclear how often LTS is related to sensitivity to chemotherapy. Methods. All patients with metastatic melanoma treated with either dacarbazine (DTIC) or temozolomide (TMZ) at the British Columbia Cancer Agency (BCCA) from January 1, 1988 to February 1, 2006 were identified through the BCCA pharmacy electronic database, which was then linked to the surveillance and outcomes unit to identify patients with LTS, defined as survival ≥18 months following chemotherapy. Results. In total, 397 patients were treated with either DTIC (n = 349) or TMZ (n = 48) and 43 patients (10.8%) were identified with LTS. Two additional patients with LTS were added prior to 1988 for a total of 45 patients. The 5-year overall and progression-free survival rates for patients with LTS were 33% and 16%, respectively. In total, 16% had a complete response (CR) to chemotherapy, which was the only factor identified that correlated with survival in the multivariate analysis. However, most patients with LTS had an incomplete response to chemotherapy. Conclusions. LTS occurs in select patients who achieve a CR to chemotherapy. However, this occurs in only a minority of patients and, in most cases, the longer survival is likely the result of indolent disease biology or host factors. PMID:20538743

  7. Radiation Therapy Dose Escalation for Glioblastoma Multiforme in the Era of Temozolomide

    SciTech Connect

    Badiyan, Shahed N.; Markovina, Stephanie; Simpson, Joseph R.; Robinson, Clifford G.; DeWees, Todd; Tran, David D.; Linette, Gerry; Jalalizadeh, Rohan; Dacey, Ralph; Rich, Keith M.; Chicoine, Michael R.; Dowling, Joshua L.; Leuthardt, Eric C.; Zipfel, Gregory J.; Kim, Albert H.; Huang, Jiayi

    2014-11-15

    Purpose: To review clinical outcomes of moderate dose escalation using high-dose radiation therapy (HDRT) in the setting of concurrent temozolomide (TMZ) in patients with newly diagnosed glioblastoma multiforme (GBM), compared with standard-dose radiation therapy (SDRT). Methods and Materials: Adult patients aged <70 years with biopsy-proven GBM were treated with SDRT (60 Gy at 2 Gy per fraction) or with HDRT (>60 Gy) and TMZ from 2000 to 2012. Biological equivalent dose at 2-Gy fractions was calculated for the HDRT assuming an α/β ratio of 5.6 for GBM. Results: Eighty-one patients received SDRT, and 128 patients received HDRT with a median (range) biological equivalent dose at 2-Gy fractions of 64 Gy (61-76 Gy). Overall median follow-up time was 1.10 years, and for living patients it was 2.97 years. Actuarial 5-year overall survival (OS) and progression-free survival (PFS) rates for patients that received HDRT versus SDRT were 12.4% versus 13.2% (P=.71), and 5.6% versus 4.1% (P=.54), respectively. Age (P=.001) and gross total/near-total resection (GTR/NTR) (P=.001) were significantly associated with PFS on multivariate analysis. Younger age (P<.0001), GTR/NTR (P<.0001), and Karnofsky performance status ≥80 (P=.001) were associated with improved OS. On subset analyses, HDRT failed to improve PFS or OS for those aged <50 years or those who had GTR/NTR. Conclusion: Moderate radiation therapy dose escalation above 60 Gy with concurrent TMZ does not seem to improve clinical outcomes for patients with GBM.

  8. Phase II Trial of Upfront Bevacizumab, Irinotecan, and Temozolomide for Unresectable Glioblastoma

    PubMed Central

    Lou, Emil; Desjardins, Annick; Reardon, David A.; Lipp, Eric S.; Miller, Elizabeth; Herndon, James E.; McSherry, Frances; Friedman, Henry S.; Vredenburgh, James J.

    2015-01-01

    Lessons Learned Trials focusing on unresectable multifocal glioblastoma are needed because of the extremely poor prognosis and challenges in receiving standard therapy, such as concurrent radiation and chemotherapy. Developing a strategy to chemically debulk tumors before radiation and/or surgery is warranted. Background. Extent of resection remains a key prognostic factor in glioblastoma (GBM), with gross total resection providing a better prognosis than biopsy or subtotal resection. We conducted a phase II trial of upfront therapy with bevacizumab (BV), irinotecan (CPT-11), and temozolomide (TMZ) prior to chemoradiation in patients with unresectable, subtotally resected, and/or multifocal GBM. Methods. Patients received up to 4 cycles of TMZ at 200 mg/m2 per day on days 1–5 (standard dosing) and BV at 10 mg/kg every 2 weeks on a 28-day cycle. CPT-11 was given every 2 weeks on a 28-day cycle at 125 mg/m2 or 340 mg/m2 depending on antiepileptic drugs. Magnetic resonance imaging of the brain was done every 4 weeks, and treatment continued as long as there was no tumor progression or unmanageable toxicity. The primary endpoint was tumor response rate, with a goal of 26% or greater. Results. Forty-one patients were enrolled from December 2009 to November 2010. Radiographic responses were as follows: 9 patients (22.0%) had partial respons!e, 25 (61.0%) had stable disease, and 2 (4.9%) had progression; 5 patients were not assessed. Cumulative response rate was 22%. Median overall survival was 12 months (95% confidence interval: 7.2–13.5 months). Conclusion. Upfront treatment with BV, TMZ, and CPT-11 is tolerable and can lead to radiographic response in unresectable and/or subtotally resected GBM. PMID:26025933

  9. TERT Promoter Mutations Lead to High Transcriptional Activity under Hypoxia and Temozolomide Treatment and Predict Poor Prognosis in Gliomas

    PubMed Central

    Meng, Lingxuan; Li, Zhonghua; Zhang, Xue; Wu, Anhua

    2014-01-01

    Objective This study explored the effects of telomerase reverse transcriptase (TERT) promoter mutations on transcriptional activity of the TERT gene under hypoxic and temozolomide (TMZ) treatment conditions, and investigated the status and prognostic value of these mutations in gliomas. Methods The effect of TERT promoter mutations on the transcriptional activity of the TERT gene under hypoxic and TMZ treatment conditions was investigated in glioma cells using the luciferase assay. TERT promoter mutations were detected in 101 glioma samples (grades I–IV) and 49 other brain tumors by sequencing. TERT mRNA expression in gliomas was examined by real-time PCR. Hazard ratios from survival analysis of glioma patients were determined relative to the presence of TERT promoter mutations. Results Mutations in the TERT promoter enhanced gene transcription even under hypoxic and TMZ treatment conditions, inducing upregulation of TERT mRNA expression. Mutations were detected in gliomas, but not in meningiomas, pituitary adenomas, cavernomas, intracranial metastases, normal brain tissues, or peripheral blood of glioma patients. Patients with TERT promoter mutations had lower survival rates, even after adjusting for other known or potential risk factors, and the incidence of mutation was correlated with patient age. Conclusion TERT promoter mutations were specific to gliomas. TERT promoter mutations maintained its ability of inducing high transcriptional activity even under hypoxic and TMZ treatment conditions, and the presence of mutations was associated with poor prognosis in glioma patients. These findings demonstrate that TERT promoter mutations are novel prognostic markers for gliomas that can inform prospective therapeutic strategies. PMID:24937153

  10. Inhibition of Na(+)-K(+)-2Cl(-) cotransporter isoform 1 accelerates temozolomide-mediated apoptosis in glioblastoma cancer cells.

    PubMed

    Algharabil, Jehad; Kintner, Douglas B; Wang, Qiwei; Begum, Gulnaz; Clark, Paul A; Yang, Sung-Sen; Lin, Shih-Hua; Kahle, Kristopher T; Kuo, John S; Sun, Dandan

    2012-01-01

    The hallmark of apoptosis is a significant reduction in cell volume (AVD) resulting from loss of K(+)(i) and Cl(-)(i). Loss of cell volume and lowering of ionic strength of intracellular K(+) and Cl(-) occur before any other detectable characteristics of apoptosis. In the present study, temozolomide (TMZ) triggered loss of K(+)(i) and Cl(-)(i) and AVD in primary glioblastoma multiforme (GBM) cancer cells (GC) and GC cancer stem cells (GSC). We hypothesize that Na(+)-K(+)-2Cl(-) cotransporter isoform 1 (NKCC1) counteracts AVD during apoptosis in GBM cancer cells by regulating cell volume and Cl(-) homeostasis. NKCC1 protein was expressed in both GC and GSC and played an essential role in regulatory volume increase (RVI) in response to hypertonic cell shrinkage and isotonic cell shrinkage. Blocking NKCC1 activity with its potent inhibitor bumetanide abolished RVI. These cells maintained a basal [Cl(-)](i) (~ 68 mM) above the electrochemical equilibrium for Cl(-)(i). NKCC1 also functioned to replenish Cl(-)(i) levels following the loss of Cl(-)(i). TMZ-treated cells exhibited increased phosphorylation of NKCC1 and its up-stream novel Cl(-)/volume-sensitive regulatory kinase WNK1. Inhibition of NKCC1 activity with bumetanide accelerated AVD, early apoptosis, as well as activation of caspase-3 and caspase-8. Taken together, this study strongly suggests that NKCC1 is an essential mechanism in GBM cells to maintain K(+), Cl(-), and volume homeostasis to counteract TMZ-induced loss of K(+), Cl(-) and AVD. Therefore, blocking NKCC1 function augments TMZ-induced apoptosis in glioma cells.

  11. Phase II Study of Short-Course Radiotherapy Plus Concomitant and Adjuvant Temozolomide in Elderly Patients With Glioblastoma

    SciTech Connect

    Minniti, Giuseppe; Lanzetta, Gaetano; Scaringi, Claudia; Caporello, Paola; Salvati, Maurizio; Arcella, Antonella; De Sanctis, Vitaliana; Giangaspero, Felice; Enrici, Riccardo Maurizi

    2012-05-01

    Purpose: Radiotherapy (RT) and chemotherapy may prolong survival in older patients (age {>=}70 years) with glioblastoma multiforme (GBM), although the survival benefits remain poor. This Phase II multicenter study was designed to evaluate the efficacy and safety of an abbreviated course of RT plus concomitant and adjuvant temozolomide (TMZ) in older patients with GBM. Patients and Methods: Seventy-one eligible patients 70 years of age or older with newly diagnosed GBM and a Karnofsky performance status {>=}60 were treated with a short course of RT (40 Gy in 15 fractions over 3 weeks) plus TMZ at the dosage of 75 mg/m{sup 2} per day followed by 12 cycles of adjuvant TMZ (150-200 mg/m{sup 2} for 5 days during each 28-day cycle). The primary endpoint was overall survival (OS). Secondary endpoints included progression-free survival and toxicity. Results: The Median OS was 12.4 months, and the 1-year and 2-year OS rates were 58% and 20%, respectively. The median and 1-year rates of progression-free survival were 6 months and 20%, respectively. All patients completed the planned programme of RT. Grade 3 or 4 adverse events occurred in 16 patients (22%). Grade 3 and 4 neutropenia and/or thrombocytopenia occurred in 10 patients (15%), leading to the interruption of treatment in 6 patients (8%). Nonhematologic Grade 3 toxicity was rare, and included fatigue in 4 patients and cognitive disability in 1 patient. Conclusions: A combination of an abbreviated course of RT plus concomitant and adjuvant TMZ is well tolerated and may prolong survival in elderly patients with GBM. Future randomized studies need to evaluate the efficacy and toxicity of different schedules of RT in association with chemotherapy.

  12. A phase II study of bevacizumab and erlotinib after radiation and temozolomide in MGMT unmethylated GBM patients

    PubMed Central

    Raizer, J. J.; Giglio, P.; Hu, J.; Groves, M.; Merrell, R.; Conrad, C.; Phuphanich, S.; Puduvalli, V. K.; Loghin, M.; Paleologos, N.; Yuan, Y.; Liu, D.; Rademaker, A.; Yung, W. K.; Vaillant, B.; Rudnick, J.; Chamberlain, M.; Vick, N.; Grimm, S.; Tremont-Lukats, I. W.; De Groot, J.; Aldape, K.; Gilbert, M. R.

    2016-01-01

    Survival for glioblastoma (GBM) patients with an unmethyated MGMT promoter in their tumor is generally worse than methylated MGMT tumors, as temozolomide (TMZ) response is limited. How to better treat patients with unmethylated MGMT is unknown. We performed a trial combining erlotinib and bevacizumab in unmethylated GBM patients after completion of radiation (RT) and TMZ. GBM patients with an unmethylated MGMT promoter were trial eligible. Patient received standard RT (60 Gy) and TMZ (75 mg/m2 × 6 weeks) after surgical resection of their tumor. After completion of RT they started erlotinib 150 mg daily and bevacizumab 10 mg/kg every 2 weeks until progression. Imaging evaluations occurred every 8 weeks. The primary endpoint was overall survival. Of the 48 unmethylated patients enrolled, 46 were evaluable (29 men and 17 women); median age was 55.5 years (29–75) and median KPS was 90 (70–100). All patients completed RT with TMZ. The median number of cycles (1 cycle was 4 weeks) was 8 (2–47). Forty-one patients either progressed or died with a median progression free survival of 9.2 months. At a follow up of 33 months the median overall survival was 13.2 months. There were no unexpected toxicities and most observed toxicities were categorized as CTC grade 1 or 2. The combination of erlotinib and bevacizumab is tolerable but did not meet our primary endpoint of increasing survival. Importantly, more trials are needed to find better therapies for GBM patients with an unmethylated MGMT promoter. PMID:26476729

  13. The effect of regadenoson-induced transient disruption of the blood-brain barrier on temozolomide delivery to normal rat brain.

    PubMed

    Jackson, Sadhana; Anders, Nicole M; Mangraviti, Antonella; Wanjiku, Teresia M; Sankey, Eric W; Liu, Ann; Brem, Henry; Tyler, Betty; Rudek, Michelle A; Grossman, Stuart A

    2016-02-01

    The blood-brain barrier (BBB) significantly reduces the delivery of many systemically administered agents to the central nervous system. Although temozolomide is the only chemotherapy to improve survival in patients with glioblastoma, its concentration in brain is only 20 % of that in blood. Regadenoson, an FDA approved adenosine receptor agonist used for cardiac stress testing, transiently disrupts rodent BBB allowing high molecular weight dextran (70 kD) to enter the brain. This study was conducted to determine if regadenoson could facilitate entry of temozolomide into normal rodent brain. Temozolomide (50 mg/kg) was administered by oral gavage to non-tumor bearing F344 rats. Two-thirds of the animals received a single dose of intravenous regadenoson 60-90 min later. All animals were sacrificed 120 or 360 min after temozolomide administration. Brain and plasma temozolomide concentrations were determined using HPLC/MS/MS. Brain temozolomide concentrations were significantly higher at 120 min when it was given with regadenoson versus alone (8.1 ± 2.7 and 5.1 ± 3.5 µg/g, P < 0.05). A similar trend was noted in brain:plasma ratios (0.45 ± 0.08 and 0.29 ± 0.09, P < 0.05). Brain concentrations and brain:plasma ratios were not significantly different 360 min after temozolomide administration. No differences were seen in plasma temozolomide concentrations with or without regadenoson. These results suggest co-administration of regadenoson with temozolomide results in 60% higher temozolomide levels in normal brain without affecting plasma concentrations. This novel approach to increasing intracranial concentrations of systemically administered agents has potential to improve the efficacy of chemotherapy in neuro-oncologic disorders.

  14. The effect of regadenoson-induced transient disruption of the blood–brain barrier on temozolomide delivery to normal rat brain

    PubMed Central

    Jackson, Sadhana; Anders, Nicole M.; Mangraviti, Antonella; Wanjiku, Teresia M.; Sankey, Eric W.; Liu, Ann; Brem, Henry; Tyler, Betty; Rudek, Michelle A.

    2016-01-01

    The blood–brain barrier (BBB) significantly reduces the delivery of many systemically administered agents to the central nervous system. Although temozolomide is the only chemotherapy to improve survival in patients with glioblastoma, its concentration in brain is only 20 % of that in blood. Regadenoson, an FDA approved adenosine receptor agonist used for cardiac stress testing, transiently disrupts rodent BBB allowing high molecular weight dextran (70 kD) to enter the brain. This study was conducted to determine if regadenoson could facilitate entry of temozolomide into normal rodent brain. Temozolomide (50 mg/kg) was administered by oral gavage to non-tumor bearing F344 rats. Two-thirds of the animals received a single dose of intravenous regadenoson 60–90 min later. All animals were sacrificed 120 or 360 min after temozolomide administration. Brain and plasma temozolomide concentrations were determined using HPLC/MS/MS. Brain temozolomide concentrations were significantly higher at 120 min when it was given with regadenoson versus alone (8.1 ± 2.7 and 5.1 ± 3.5 μg/g, P <0.05). A similar trend was noted in brain:plasma ratios (0.45 ± 0.08 and 0.29 ± 0.09, P < 0.05). Brain concentrations and brain:plasma ratios were not significantly different 360 min after temozolomide administration. No differences were seen in plasma temozolomide concentrations with or without regadenoson. These results suggest co-administration of regadenoson with temozolomide results in 60 % higher temozolomide levels in normal brain without affecting plasma concentrations. This novel approach to increasing intracranial concentrations of systemically administered agents has potential to improve the efficacy of chemotherapy in neuro-oncologic disorders. PMID:26626489

  15. Preclinical impact of bevacizumab on brain and tumor distribution of irinotecan and temozolomide.

    PubMed

    Goldwirt, Lauriane; Beccaria, Kevin; Carpentier, Alexandre; Idbaih, Ahmed; Schmitt, Charlotte; Levasseur, Camille; Labussiere, Marianne; Milane, Aline; Farinotti, Robert; Fernandez, Christine

    2015-04-01

    Glioblastoma (GBM) is the most common primary malignant brain tumour in adults. Prognosis of GBM patients is poor with median overall survival around 15 months. Temozolomide is the chemotherapeutic agent used in the standard of care of newly diagnosed GBM patients relying on radiotherapy with concurrent chemotherapy followed by chemotherapy alone. Irinotecan has shown some efficacy in recurrent malignant gliomas. Bevacizumab has been combined with irinotecan in the treatment of recurrent GBM and with temozolomide in newly diagnosed GBM. As the efficacy of GBM treatments relies on their brain distribution through the blood brain barrier, the aim of the present preclinical work was to study, in in vivo models, the impact of bevacizumab on brain and tumor distribution of temozolomide and irinotecan. Our results show that bevacizumab pre-treatment was associated with a reduced temozolomide brain distribution in tumor-free mice. In tumor bearing mice, bevacizumab increased temozolomide tumor distribution, although not statistically significant. In both tumor-free and tumor-bearing mice, bevacizumab does not modify brain distribution of irinotecan and its metabolite SN-38. Bevacizumab impacts brain distribution of some anti-tumor drugs and potentially their efficacy in GBM. Further studies are warranted to investigate other therapeutic combination.

  16. Temozolomide-Associated Bronchiolitis Obliterans Organizing Pneumonia Successfully Treated with High-Dose Corticosteroid

    PubMed Central

    Kim, Tae-Ok; Kang, Hyun-Wook; Chi, Su-Young; Ban, Hee-Jung; Kwon, Yong-Soo; Kim, Kyu-Sik; Kim, Yu-Il; Lim, Sung-Chul; Kim, Young-Chul

    2012-01-01

    Temozolomide is an oral alkylating agent with clinical activity against glioblastoma multiforme (GM). It is generally well-tolerated and has few pulmonary side effects. We report a case of temozolomide-associated brochiolitis obliterans organizing pneumonia (BOOP) requiring very high-dose corticosteroid treatment. A 56-yr-old woman presented with a 2-week history of exertional dyspnea. For the treatment of GM diagnosed 4 months previously, she had undergone surgery followed by chemoradiotherapy, and then planned adjuvant chemotherapy with temozolomide. After the 1st cycle, progressive dyspnea was gradually developed. Chest radiograph showed diffuse patchy peribronchovascular ground-glass opacities in both lungs. Conventional dose of methylprednisolone (1 mg/kg/day) was begun for the possibility of BOOP. Although transbronchial lung biopsy findings were compatible with BOOP, the patient's clinical course was more aggravated until hospital day 5. After the dose of methylprednisolone was increased (500 mg/day for 5 days) radiologic findings were improved dramatically. PMID:22468112

  17. Comparison of the effectiveness of whole-brain radiotherapy plus temozolomide versus whole-brain radiotherapy in treating brain metastases based on a systematic review of randomized controlled trials.

    PubMed

    Bai, Gui-Rong; An, Jin-Bing; Chu, Yang; Wang, Xiang-Yang; Li, Shu-Ming; Yan, Kai-Jing; Lü, Fu-Rong; Gu, Ning; Griffin, Amanda N; Sun, Bin-Yuan; Li, Wei; Wang, Guo-Cheng; Zhou, Shui-Ping; Sun, He; Liu, Chang-Xiao

    2016-01-01

    Temozolomide (TMZ) combination with whole-brain radiotherapy (WBRT) has been tested by many randomized controlled trials in the treatment of brain metastases (BMs) in China and other countries. We performed an up-to-date meta-analysis to determine (i) the log odds ratios (LORs) of objective response (ORR) and adverse effects (AEs) for all-grade, and (ii) the T value of mean overall survival in patients with BMs treated with WBRT combined with TMZ versus WBRT alone. PubMed, Chinese National Knowledge Infrastructure, and WanFang Data were searched for articles published up to 28 January 2015. Eligible studies were selected according to the PRISMA statement. ORR, AEs, and 95% confidence intervals were calculated using random-effects models. Eighteen studies were included in our analysis. A total of 1028 participants were enrolled. Summary LORs of ORR were 1.0239 (P<0.0001) on comparing WBRT plus TMZ with WBRT ORR (n=17). The overall mean difference of mean overall survival (n=17) between TMZ plus WBRT and WBRT was 2.2505 weeks (P=0.02185). There was a significant difference between WBRT plus TMZ and WBRT alone with a LOR of AEs for all-grade of (i) 0.923 for gastrointestinal toxicity and (ii) 0.7978 for myelosuppression. Sensitivity analysis and subgroup analysis were also performed. The 18 eligible randomized controlled trials demonstrated that the combination of WBRT and TMZ significantly improves the ORR and is statistically insignificant in prolonging the survival of patients with BMs. In addition, an increase in the incidence of gastrointestinal toxicity and myelosuppression was significant for all-grade. PMID:26426520

  18. A Phase I/II study of lomustine and temozolomide in patients with cerebral metastases from malignant melanoma

    PubMed Central

    Larkin, J M G; Hughes, S A; Beirne, D A; Patel, P M; Gibbens, I M; Bate, S C; Thomas, K; Eisen, T G; Gore, M E

    2006-01-01

    Temozolomide is an alkylating agent with activity in the treatment of melanoma metastatic to the brain. Lomustine is a nitrosurea that crosses the blood brain barrier and there is evidence to suggest that temozolomide may reverse resistance to lomustine. A multicentre phase I/II study was conducted to assess the maximum-tolerated dose (MTD), safety and efficacy of the combination of temozolomide and lomustine in melanoma metastatic to the brain. Increasing doses of temozolomide and lomustine were administered in phase I of the study to determine the MTD. Patients were treated at the MTD in phase II of the study to six cycles, disease progression or unacceptable toxicity. Twenty-six patients were enrolled in the study. In phase I of the study, the MTD was defined as temozolomide 150 mg m−2 days 1–5 every 28 days and lomustine 60 mg m–2 on day 5 every 56 days. Dose-limiting neutropaenia and thrombocytopaenia were observed at higher doses. Twenty patients were treated at this dose in phase II of the study. No responses to therapy were observed. Median survival from starting chemotherapy was 2 months. The combination of temozolomide and lomustine in patients with brain metastases from melanoma does not demonstrate activity. The further evaluation of this combination therefore is not warranted. PMID:17146474

  19. A phase I/II study of lomustine and temozolomide in patients with cerebral metastases from malignant melanoma.

    PubMed

    Larkin, J M G; Hughes, S A; Beirne, D A; Patel, P M; Gibbens, I M; Bate, S C; Thomas, K; Eisen, T G; Gore, M E

    2007-01-15

    Temozolomide is an alkylating agent with activity in the treatment of melanoma metastatic to the brain. Lomustine is a nitrosurea that crosses the blood brain barrier and there is evidence to suggest that temozolomide may reverse resistance to lomustine. A multicentre phase I/II study was conducted to assess the maximum-tolerated dose (MTD), safety and efficacy of the combination of temozolomide and lomustine in melanoma metastatic to the brain. Increasing doses of temozolomide and lomustine were administered in phase I of the study to determine the MTD. Patients were treated at the MTD in phase II of the study to six cycles, disease progression or unacceptable toxicity. Twenty-six patients were enrolled in the study. In phase I of the study, the MTD was defined as temozolomide 150 mg m(-2) days 1-5 every 28 days and lomustine 60 mg m(-2) on day 5 every 56 days. Dose-limiting neutropaenia and thrombocytopaenia were observed at higher doses. Twenty patients were treated at this dose in phase II of the study. No responses to therapy were observed. Median survival from starting chemotherapy was 2 months. The combination of temozolomide and lomustine in patients with brain metastases from melanoma does not demonstrate activity. The further evaluation of this combination therefore is not warranted. PMID:17146474

  20. Comparison of Corticotropin-Releasing Factor, Dexamethasone and Temozolomide: Treatment Efficacy and Toxicity in U87 and C6 Intracranial Gliomas

    PubMed Central

    Moroz, Maxim A.; Huang, Ruimin; Kochetkov, Tatiana; Shi, Weiji; Thaler, Howard; de Stanchina, Elisa; Gamez, Idoia; Ryan, Robert P.; Blasberg, Ronald G.

    2011-01-01

    Treatment of cerebral tumors and peritumoral brain edema remains a clinical challenge and is associated with high morbidity and mortality. Dexamethasone (DEX) is an effective drug to treat brain edema, but is associated with well-described side effects. Corticorelin acetate (Xerecept) or human corticotrophin releasing factor (hCRF) is a comparatively new drug and was evaluated in two orthotopic glioma models (U87 and C6), by a direct comparison with dexamethasone and temozolomide. In vitro mono- and combination-treatments showed a variable response in 6 different glioma cell lines. In vivo studies showed a dose-dependent effect of hCRF (0.03 and 0.1 mg/kg/q12h) on survival of U87 intracranial xenograft-bearing animals [median survival: control 41 days (95% CI 25–61 d); “low-hCRF” 74.5 d (95% CI 41–88 d); “high-hCRF” >130 d (95% CI not reached)]. Dexamethasone treatment had no effect on survival, but significant toxicity was observed. A survival benefit was observed with TMZ and TMZ + hCRF - treated animals, but with significant TMZ toxicity. C6-bearing animals showed no survival benefit, but similar treatment toxicities. The difference in hCRF-treatment response between U87- and C6-intracranial gliomas can be explained by a difference in receptor expression. RT-PCR identified CRF2r mRNA in U87-xenografts; no CRF-receptors were identified in C6-xenografts. HCRF was more effective than either dexamethasone or temozolomide in the treatment of U87 xenografts, with long-term survivors and only mild toxicity. HCRF therapeutic efficacy appears to be dependent on tumor hCRF-receptor expression. These results support further clinical assessment hCRF therapeutic efficacy and levels of CRFr expression in different human gliomas. PMID:21385926

  1. Comparative Analysis of Matrix Metalloproteinase Family Members Reveals That MMP9 Predicts Survival and Response to Temozolomide in Patients with Primary Glioblastoma

    PubMed Central

    Cai, Jinquan; Sun, Ying; Wang, Guangzhi; Li, Yongli; Li, Ruiyan; Feng, Yan; Han, Bo; Li, Jianlong; Tian, Yu; Yi, Liye; Jiang, Chuanlu

    2016-01-01

    Background Glioblastoma multiform (GBM) is the most common malignant primary brain tumor in adults. Radiotherapy plus concomitant and adjuvant TMZ chemotherapy is the current standard of care for patients with GBM. Matrix metalloproteinases (MMPs), a family of zinc-dependent endopeptidases, are key modulators of tumor invasion and metastasis due to their ECM degradation capacity. The aim of the present study was to identify the most informative MMP member in terms of prognostic and predictive ability for patients with primary GBM. Method The mRNA expression profiles of all MMP genes were obtained from the Chinese Glioma Genome Atlas (CGGA), the Repository for Molecular Brain Neoplasia Data (REMBRANDT) and the GSE16011 dataset. MGMT methylation status was also examined by pyrosequencing. The correlation of MMP9 expression with tumor progression was explored in glioma specimens of all grades. Kaplan–Meier analysis and Cox proportional hazards regression models were used to investigate the association of MMP9 expression with survival and response to temozolomide. Results MMP9 was the only significant prognostic factor in three datasets for primary glioblastoma patients. Our results indicated that MMP9 expression is correlated with glioma grade (p<0.0001). Additionally, low expression of MMP9 was correlated with better survival outcome (OS: p = 0.0012 and PFS: p = 0.0066), and MMP9 was an independent prognostic factor in primary GBM (OS: p = 0.027 and PFS: p = 0.032). Additionally, the GBM patients with low MMP9 expression benefited from temozolomide (TMZ) chemotherapy regardless of the MGMT methylation status. Conclusions Patients with primary GBMs with low MMP9 expression may have longer survival and may benefit from temozolomide chemotherapy. PMID:27022952

  2. MiR-203 sensitizes glioma cells to temozolomide and inhibits glioma cell invasion by targeting E2F3.

    PubMed

    Tang, Guodong; Wu, Jun; Xiao, Gelei; Huo, Lei

    2015-04-01

    Glioma is the most common malignant and fatal primary tumor in the central nervous system in adults. Recent data has suggested a profound role for microRNAs (miRs) in cancer progression. The present study demonstrated, via quantitative polymerase chain reaction (qPCR) analysis, that miR-203 expression was markedly lower in highly invasive U87MG glioma cells and glioma tissues. Wound healing and Transwell assays demonstrated that restoration of miR-203 expression inhibited U87MG cell migration and invasion. Restoration of miR-203 expression additionally sensitized the cells to temozolomide (TMZ) as determined by MTS assay. By contrast, miR-203 inhibition in A172 cells exerted opposite effects. Bioinformatic analysis combined with experimental analysis revealed that miR-203 directly targeted E2F3 via the conserved miR-203 target site within the E2F3 3'-untranslational region. E2F3 knockdown with specific small hairpin RNA also inhibited U87MG cell migration and invasion, and sensitized them to TMZ. Importantly, miR-203 and E2F3 showed inverse expression patterns in invasive glioma tissues, as demonstrated by qPCR and luciferase assay. These results suggested that miR-203 may function as a tumor suppressor in glioma progression and that the miR-203/E2F3 axis may be a novel candidate in the development of rational therapeutic strategies for glioma.

  3. Clinical and Dosimetric Predictors of Acute Severe Lymphopenia During Radiation Therapy and Concurrent Temozolomide for High-Grade Glioma

    SciTech Connect

    Huang, Jiayi; DeWees, Todd A.; Badiyan, Shahed N.; Speirs, Christina K.; Mullen, Daniel F.; Fergus, Sandra; Tran, David D.; Linette, Gerry; Campian, Jian L.; Chicoine, Michael R.; Kim, Albert H.; Dunn, Gavin; Simpson, Joseph R.; Robinson, Clifford G.

    2015-08-01

    Purpose: Acute severe lymphopenia (ASL) frequently develops during radiation therapy (RT) and concurrent temozolomide (TMZ) for high-grade glioma (HGG) and is associated with decreased survival. The current study was designed to identify potential predictors of ASL, with a focus on actionable RT-specific dosimetric parameters. Methods and Materials: From January 2007 to December 2012, 183 patients with HGG were treated with RT+TMZ and had available data including total lymphocyte count (TLC) and radiation dose-volume histogram parameters. ASL was defined as TLC of <500/μL within the first 3 months from the start of RT. Stepwise logistic regression analysis was used to determine the most important predictors of ASL. Results: Fifty-three patients (29%) developed ASL. Patients with ASL had significantly worse overall survival than those without (median: 12.5 vs 20.2 months, respectively, P<.001). Stepwise logistic regression analysis identified female sex (odds ratio [OR]: 5.30; 95% confidence interval [CI]: 2.46-11.41), older age (OR: 1.05; 95% CI: 1.02-1.09), lower baseline TLC (OR: 0.92; 95% CI: 0.87-0.98), and higher brain volume receiving 25 Gy (V{sub 25Gy}) (OR: 1.03; 95% CI: 1.003-1.05) as the most significant predictors for ASL. Brain V{sub 25Gy} <56% appeared to be the optimal threshold (OR: 2.36; 95% CI: 1.11-5.01), with an ASL rate of 38% versus 20% above and below this threshold, respectively (P=.006). Conclusions: Female sex, older age, lower baseline TLC, and higher brain V{sub 25Gy} are significant predictors of ASL during RT+TMZ therapy for HGG. Maintaining the V{sub 25Gy} of brain below 56% may reduce the risk of ASL.

  4. Up-regulation of miR-370-3p restores glioblastoma multiforme sensitivity to temozolomide by influencing MGMT expression

    PubMed Central

    Gao, Yong-tao; Chen, Xiao-bing; Liu, Hong-lin

    2016-01-01

    MicroRNAs (miRNA) are believed to play an important role in glioblastoma multiforme (GBM)chemotherapy. Our study aims to investigate potential miRNA biomarkers in GBM. Sixty GBM patients, which were given temozolomide (TMZ) chemotherapy and recurrent radiotherapy, were recruited. miRNA array was performed in cancerous and in paired normal tissues. Microarray results were further validated by a quantitative real-time PCR in selected tissues and GBM cell lines. TMZ resistance cells were developed and cell proliferation along with colony formation assays was determined. Our study employed H2AX formation and flow cytometry to analyse the role of miRNA in DNA damage and apoptosis. Our study illustrated 16 miRNA in which 9 were up-regulated and 7 down-regulated. and their differential expression were demonstrated in a recurrent GBM tissue. Among them, miRNA-370-3p demonstrated the highest level of down- regulation in tissues and in TMZ resistance cells. miRNA-370-3p mimic increased its expression and sensitivity of GBM cells to TMZ by suppressing the self-reparative ability of tumour cell DNA. O6-methylguanine-DNA methyltransferase (MGMT) was identified as the direct target gene of miR-370-3p, and it was found to be inversely correlated with miR-370-3p expression in tissue samples obtained. Thus, our study demonstrated a critical clinical role of an up-regulated miR-370-3p expression in glioblastoma multiforme chemotherapy sensitivity. PMID:27595933

  5. Up-regulation of miR-370-3p restores glioblastoma multiforme sensitivity to temozolomide by influencing MGMT expression.

    PubMed

    Gao, Yong-Tao; Chen, Xiao-Bing; Liu, Hong-Lin

    2016-01-01

    MicroRNAs (miRNA) are believed to play an important role in glioblastoma multiforme (GBM)chemotherapy. Our study aims to investigate potential miRNA biomarkers in GBM. Sixty GBM patients, which were given temozolomide (TMZ) chemotherapy and recurrent radiotherapy, were recruited. miRNA array was performed in cancerous and in paired normal tissues. Microarray results were further validated by a quantitative real-time PCR in selected tissues and GBM cell lines. TMZ resistance cells were developed and cell proliferation along with colony formation assays was determined. Our study employed H2AX formation and flow cytometry to analyse the role of miRNA in DNA damage and apoptosis. Our study illustrated 16 miRNA in which 9 were up-regulated and 7 down-regulated. and their differential expression were demonstrated in a recurrent GBM tissue. Among them, miRNA-370-3p demonstrated the highest level of down- regulation in tissues and in TMZ resistance cells. miRNA-370-3p mimic increased its expression and sensitivity of GBM cells to TMZ by suppressing the self-reparative ability of tumour cell DNA. O(6)-methylguanine-DNA methyltransferase (MGMT) was identified as the direct target gene of miR-370-3p, and it was found to be inversely correlated with miR-370-3p expression in tissue samples obtained. Thus, our study demonstrated a critical clinical role of an up-regulated miR-370-3p expression in glioblastoma multiforme chemotherapy sensitivity. PMID:27595933

  6. Up-regulation of miR-370-3p restores glioblastoma multiforme sensitivity to temozolomide by influencing MGMT expression.

    PubMed

    Gao, Yong-Tao; Chen, Xiao-Bing; Liu, Hong-Lin

    2016-01-01

    MicroRNAs (miRNA) are believed to play an important role in glioblastoma multiforme (GBM)chemotherapy. Our study aims to investigate potential miRNA biomarkers in GBM. Sixty GBM patients, which were given temozolomide (TMZ) chemotherapy and recurrent radiotherapy, were recruited. miRNA array was performed in cancerous and in paired normal tissues. Microarray results were further validated by a quantitative real-time PCR in selected tissues and GBM cell lines. TMZ resistance cells were developed and cell proliferation along with colony formation assays was determined. Our study employed H2AX formation and flow cytometry to analyse the role of miRNA in DNA damage and apoptosis. Our study illustrated 16 miRNA in which 9 were up-regulated and 7 down-regulated. and their differential expression were demonstrated in a recurrent GBM tissue. Among them, miRNA-370-3p demonstrated the highest level of down- regulation in tissues and in TMZ resistance cells. miRNA-370-3p mimic increased its expression and sensitivity of GBM cells to TMZ by suppressing the self-reparative ability of tumour cell DNA. O(6)-methylguanine-DNA methyltransferase (MGMT) was identified as the direct target gene of miR-370-3p, and it was found to be inversely correlated with miR-370-3p expression in tissue samples obtained. Thus, our study demonstrated a critical clinical role of an up-regulated miR-370-3p expression in glioblastoma multiforme chemotherapy sensitivity.

  7. AKT2-knockdown suppressed viability with enhanced apoptosis, and attenuated chemoresistance to temozolomide of human glioblastoma cells in vitro and in vivo

    PubMed Central

    Cui, Yong; Lin, Jing; Zuo, Jianling; Zhang, Lei; Dong, Yan; Hu, Guohan; Luo, Chun; Chen, Juxiang; Lu, Yicheng

    2015-01-01

    The AKT2 kinase (protein kinase Bβ) is overexpressed in high-grade gliomas. Upregulation of the AKT2 gene has been previously observed in glioblastoma patients suffering from chemotherapy failure and tumor progress. In this study, we aimed to evaluate the effect of AKT2 on viability and chemoresistance in the human glioblastoma cell line U251. The U251 cell line was stably transfected with short hairpin RNA (shRNA) targeting AKT2. U251 cells underexpressing AKT2 were then examined for viability with temozolomide (TMZ) treatment, and tested for cell apoptosis both in vitro and in tumor-implanted mice. Next, expressions of several chemoresistance-related molecules were measured by quantitative reverse-transcription polymerase chain reaction (qRT-PCR) and western blot analysis. The results showed that the 50% inhibitory concentration (IC50) of AKT2 shRNA-transfected cells was significantly lower compared with Lenti-GFP-transfected and nontransfected controls and that the tumor growth of the AKT2-shRNA and TMZ combined-treated mice was obviously suppressed in either mass or volume. Concomitantly, the apoptosis of TMZ-treated tumor cells was significantly enhanced after knockdown of AKT2, as measured by flow cytometry and in situ terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) analysis. Furthermore, AKT2-inhibition in TMZ-treated glioblastoma U251 cells upregulated apoptotic effector caspase-3, whereas it downregulated antiapoptotic protein Bcl-2, DNA repairing protein MGMT, and drug efflux pump protein MRP1. Our study identified AKT2 as an important gene in presenting chemoresistance in glioblastoma, and a potential target to potentiate the clinical effect of chemotherapy in glioma treatment. PMID:26185456

  8. Phase II Pilot Study of Bevacizumab in Combination with Temozolomide and Regional Radiation Therapy for Up-Front Treatment of Patients With Newly Diagnosed Glioblastoma Multiforme: Interim Analysis of Safety and Tolerability

    SciTech Connect

    Lai, Albert Filka, Emese; McGibbon, Bruce; Nghiemphu, Phioanh Leia; Graham, Carrie; Yong, William H.; Mischel, Paul; Liau, Linda M.; Bergsneider, Marvin; Pope, Whitney; Selch, Michael; Cloughesy, Tim

    2008-08-01

    Purpose: To assess interim safety and tolerability of a 10-patient, Phase II pilot study using bevacizumab (BV) in combination with temozolomide (TMZ) and regional radiation therapy (RT) in the up-front treatment of patients with newly diagnosed glioblastoma. Methods and Materials: All patients received standard external beam regional RT of 60.0 Gy in 30 fractions started within 3 to 5 weeks after surgery. Concurrently TMZ was given daily at 75 mg/m{sup 2} for 42 days during RT, and BV was given every 2 weeks at 10 mg/kg starting with the first day of RT/TMZ. After a 2-week interval upon completion of RT, the post-RT phase commenced with resumption of TMZ at 150 to 200 mg/m{sup 2} for 5 days every 4 weeks and continuation of BV every 2 weeks. Results: For these 10 patients, toxicities were compiled until study discontinuation or up to {approx}40 weeks from initial study treatment for those remaining on-study. In terms of serious immediate or delayed neurotoxicity, 1 patient developed presumed radiation-induced optic neuropathy. Among the toxicities that could be potentially treatment related, relatively high incidences of fatigue, myelotoxicity, wound breakdown, and deep venous thrombosis/pulmonary embolism were observed. Conclusion: The observed toxicities were acceptable to continue enrollment toward the overall target group of 70 patients. Preliminary efficacy analysis shows encouraging mean progression-free survival. At this time data are not sufficient to encourage routine off-label use of BV combined with TMZ/RT in the setting of newly diagnosed glioblastoma without longer follow-up, enrollment of additional patients, and thorough efficacy assessment.

  9. Phase I dose-escalation study of the PI3K/mTOR inhibitor voxtalisib (SAR245409, XL765) plus temozolomide with or without radiotherapy in patients with high-grade glioma

    PubMed Central

    Wen, Patrick Y.; Omuro, Antonio; Ahluwalia, Manmeet S.; Fathallah-Shaykh, Hassan M.; Mohile, Nimish; Lager, Joanne J.; Laird, A. Douglas; Tang, Jiali; Jiang, Jason; Egile, Coumaran; Cloughesy, Timothy F.

    2015-01-01

    Background This phase I study aimed to evaluate safety, maximum tolerated dose, pharmacokinetics, pharmacodynamics, and preliminary efficacy of voxtalisib (SAR245409, XL765), a pan-class I phosphoinositide 3-kinase (PI3K) and mammalian target of rapamycin (mTOR) inhibitor, in combination with temozolomide (TMZ), with or without radiation therapy (RT), in patients with high-grade glioma. Methods Patients received voxtalisib 30–90 mg once daily (q.d.) or 20–50 mg twice daily (b.i.d.), in combination with 200 mg/m2 TMZ (n = 49), or voxtalisib 20 mg q.d. with 75 mg/m2 TMZ and RT (n = 5). A standard 3 + 3 dose-escalation design was used to determine the maximum tolerated dose. Patients were evaluated for adverse events (AEs), plasma pharmacokinetics, pharmacodynamic effects in skin biopsies, and tumor response. Results The maximum tolerated doses were 90 mg q.d. and 40 mg b.i.d. for voxtalisib in combination with TMZ. The most frequently reported treatment-related AEs were nausea (48%), fatigue (43%), thrombocytopenia (26%), and diarrhea (24%). The most frequently reported treatment-related grade ≥3 AEs were lymphopenia (13%), thrombocytopenia, and decreased platelet count (9% each). Pharmacokinetic parameters were similar to previous studies with voxtalisib monotherapy. Moderate inhibition of PI3K signaling was observed in skin biopsies. Best response was partial response in 4% of evaluable patients, with stable disease observed in 68%. Conclusions Voxtalisib in combination with TMZ with or without RT in patients with high-grade gliomas demonstrated a favorable safety profile and a moderate level of PI3K/mTOR pathway inhibition. PMID:26019185

  10. A Phase 3 Trial of Whole Brain Radiation Therapy and Stereotactic Radiosurgery Alone Versus WBRT and SRS With Temozolomide or Erlotinib for Non-Small Cell Lung Cancer and 1 to 3 Brain Metastases: Radiation Therapy Oncology Group 0320

    SciTech Connect

    Sperduto, Paul W.; Wang, Meihua; Robins, H. Ian; Schell, Michael C.; Werner-Wasik, Maria; Komaki, Ritsuko; Souhami, Luis; Buyyounouski, Mark K.; Khuntia, Deepak; Demas, William; Shah, Sunjay A.; Nedzi, Lucien A.; Perry, Gad; Suh, John H.; Mehta, Minesh P.

    2013-04-01

    Background: A phase 3 Radiation Therapy Oncology Group (RTOG) study subset analysis demonstrated improved overall survival (OS) with the addition of stereotactic radiosurgery (SRS) to whole brain radiation therapy (WBRT) in non-small cell lung cancer (NSCLC) patients with 1 to 3 brain metastases. Because temozolomide (TMZ) and erlotinib (ETN) cross the blood-brain barrier and have documented activity in NSCLC, a phase 3 study was designed to test whether these drugs would improve the OS associated with WBRT + SRS. Methods and Materials: NSCLC patients with 1 to 3 brain metastases were randomized to receive WBRT (2.5 Gy × 15 to 37.5 Gy) and SRS alone, versus WBRT + SRS + TMZ (75 mg/m{sup 2}/day × 21 days) or ETN (150 mg/day). ETN (150 mg/day) or TMZ (150-200 mg/m{sup 2}/day × 5 days/month) could be continued for as long as 6 months after WBRT + SRS. The primary endpoint was OS. Results: After 126 patients were enrolled, the study closed because of accrual limitations. The median survival times (MST) for WBRT + SRS, WBRT + SRS + TMZ, and WBRT + SRS + ETN were qualitatively different (13.4, 6.3, and 6.1 months, respectively), although the differences were not statistically significant. Time to central nervous system progression and performance status at 6 months were better in the WBRT + SRS arm. Grade 3 to 5 toxicity was 11%, 41%, and 49% in arms 1, 2, and 3, respectively (P<.001). Conclusion: The addition of TMZ or ETN to WBRT + SRS in NSCLC patients with 1 to 3 brain metastases did not improve survival and possibly had a deleterious effect. Because the analysis is underpowered, these data suggest but do not prove that increased toxicity was the cause of inferior survival in the drug arms.

  11. Hepatic encephalopathy after treatment with temozolomide.

    PubMed

    Goldbecker, Annemarie; Tryc, Anita Blanka; Raab, Peter; Worthmann, Hans; Herrmann, Julian; Weissenborn, Karin

    2011-05-01

    Temozolomide in combination with radiation has been in use for more than 5 years for the therapy of glioblastoma. Known adverse effects concerning the gastrointestinal system are elevation of liver enzymes. We present the case of a patient treated with temozolomide who developed severe cholestatic liver damage and consecutive hepatic encephalopathy. Neurological symptoms were mistaken as being caused by focal brain damage for more than 9 months. After the correct diagnosis had been made and the treatment had been started, the patient's condition ameliorated. In conclusion, neurological deficits in patients with known brain lesion should not be attributed automatically to the pre-existing damage even if it is progressive but should be examined carefully, also including toxic and metabolic encephalopathies into the differential diagnosis. Furthermore, new side effects of drugs have to be considered. At least this case might lead to a closer monitoring of liver enzymes during temozolomide therapy.

  12. Temozolomide down-regulates P-glycoprotein in human blood-brain barrier cells by disrupting Wnt3 signaling.

    PubMed

    Riganti, Chiara; Salaroglio, Iris C; Pinzòn-Daza, Martha L; Caldera, Valentina; Campia, Ivana; Kopecka, Joanna; Mellai, Marta; Annovazzi, Laura; Couraud, Pierre-Olivier; Bosia, Amalia; Ghigo, Dario; Schiffer, Davide

    2014-02-01

    Low delivery of many anticancer drugs across the blood-brain barrier (BBB) is a limitation to the success of chemotherapy in glioblastoma. This is because of the high levels of ATP-binding cassette transporters like P-glycoprotein (Pgp/ABCB1), which effluxes drugs back to the bloodstream. Temozolomide is one of the few agents able to cross the BBB; its effects on BBB cells permeability and Pgp activity are not known. We found that temozolomide, at therapeutic concentration, increased the transport of Pgp substrates across human brain microvascular endothelial cells and decreased the expression of Pgp. By methylating the promoter of Wnt3 gene, temozolomide lowers the endogenous synthesis of Wnt3 in BBB cells, disrupts the Wnt3/glycogen synthase kinase 3/β-catenin signaling, and reduces the binding of β-catenin on the promoter of mdr1 gene, which encodes for Pgp. In co-culture models of BBB cells and human glioblastoma cells, pre-treatment with temozolomide increases the delivery, cytotoxicity, and antiproliferative effects of doxorubicin, vinblastine, and topotecan, three substrates of Pgp that are usually poorly delivered across BBB. Our work suggests that temozolomide increases the BBB permeability of drugs that are normally effluxed by Pgp back to the bloodstream. These findings may pave the way to new combinatorial chemotherapy schemes in glioblastoma.

  13. Resistance to DNA Damaging Agents Produced Invasive Phenotype of Rat Glioma Cells-Characterization of a New in Vivo Model.

    PubMed

    Stojković, Sonja; Podolski-Renić, Ana; Dinić, Jelena; Pavković, Željko; Ayuso, Jose M; Fernández, Luis J; Ochoa, Ignacio; Pérez-García, Victor M; Pešić, Vesna; Pešić, Milica

    2016-01-01

    Chemoresistance and invasion properties are severe limitations to efficient glioma therapy. Therefore, development of glioma in vivo models that more accurately resemble the situation observed in patients emerges. Previously, we established RC6 rat glioma cell line resistant to DNA damaging agents including antiglioma approved therapies such as 3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and temozolomide (TMZ). Herein, we evaluated the invasiveness of RC6 cells in vitro and in a new orthotopic animal model. For comparison, we used C6 cells from which RC6 cells originated. Differences in cell growth properties were assessed by real-time cell analyzer. Cells' invasive potential in vitro was studied in fluorescently labeled gelatin and by formation of multicellular spheroids in hydrogel. For animal studies, fluorescently labeled cells were inoculated into adult male Wistar rat brains. Consecutive coronal and sagittal brain sections were analyzed 10 and 25 days post-inoculation, while rats' behavior was recorded during three days in the open field test starting from 25th day post-inoculation. We demonstrated that development of chemoresistance induced invasive phenotype of RC6 cells with significant behavioral impediments implying usefulness of orthotopic RC6 glioma allograft in preclinical studies for the examination of new approaches to counteract both chemoresistance and invasion of glioma cells. PMID:27355941

  14. Resistance to DNA Damaging Agents Produced Invasive Phenotype of Rat Glioma Cells-Characterization of a New in Vivo Model.

    PubMed

    Stojković, Sonja; Podolski-Renić, Ana; Dinić, Jelena; Pavković, Željko; Ayuso, Jose M; Fernández, Luis J; Ochoa, Ignacio; Pérez-García, Victor M; Pešić, Vesna; Pešić, Milica

    2016-06-27

    Chemoresistance and invasion properties are severe limitations to efficient glioma therapy. Therefore, development of glioma in vivo models that more accurately resemble the situation observed in patients emerges. Previously, we established RC6 rat glioma cell line resistant to DNA damaging agents including antiglioma approved therapies such as 3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and temozolomide (TMZ). Herein, we evaluated the invasiveness of RC6 cells in vitro and in a new orthotopic animal model. For comparison, we used C6 cells from which RC6 cells originated. Differences in cell growth properties were assessed by real-time cell analyzer. Cells' invasive potential in vitro was studied in fluorescently labeled gelatin and by formation of multicellular spheroids in hydrogel. For animal studies, fluorescently labeled cells were inoculated into adult male Wistar rat brains. Consecutive coronal and sagittal brain sections were analyzed 10 and 25 days post-inoculation, while rats' behavior was recorded during three days in the open field test starting from 25th day post-inoculation. We demonstrated that development of chemoresistance induced invasive phenotype of RC6 cells with significant behavioral impediments implying usefulness of orthotopic RC6 glioma allograft in preclinical studies for the examination of new approaches to counteract both chemoresistance and invasion of glioma cells.

  15. Role of Evaluating MGMT Status and 1p36 Deletion in Radiosurgery-Induced Anaplastic Ependymoma That Rapidly and Completely Resolved by Temozolomide Alone: Case Report and Review of the Literature.

    PubMed

    Hirono, Seiichiro; Iwadate, Yasuo; Kambe, Michiyo; Hiwasa, Takaki; Takiguchi, Masaki; Nakatani, Yukio; Saeki, Naokatsu

    2015-07-01

    Stereotactic gamma knife surgery (GKS)-induced brain tumors are extremely rare, and no ependymal tumors induced by GKS have been reported. Therefore, little is known about their clinical, pathologic, and genetic features. In addition, a regimen of adjuvant chemotherapy for anaplastic ependymoma (AE) has not been established. A 77-year-old man presented with a gait disturbance and left-side cerebellar ataxia more than 19 years after GKS performed for a cerebellar arteriovenous malformation. Imaging studies demonstrated an enhancing mass in the irradiated field with signs of intraventricular dissemination. Surgical resection confirmed the diagnosis of AE. Temozolomide (TMZ) was administrated postoperatively because the methylated promoter region of O(6)-methylguanine-DNA methyltransferase (MGMT) and 1p36 deletion were observed. Surprisingly, images 16 days after TMZ initiation demonstrated a complete resolution of the residual tumor that was maintained after three cycles of TMZ. This first case report of GKS-induced AE emphasizes the importance of genetic evaluation of MGMT and chromosomal deletion of 1p36 that are not commonly performed in primary ependymal tumors. In addition, it is speculated that a GKS-induced tumor may have a different genetic background compared with the primary tumor because the pathogenesis of the tumors differed.

  16. Treatment of Aggressive Prolactin-Secreting Pituitary Adenomas with Adjuvant Temozolomide Chemotherapy: A Review

    PubMed Central

    Cruz, Aurora S; Benkers, Tara; Rostad, Steven; Broyles, Frances Broyles; Yuen, Kevin; Mayberg, Marc

    2016-01-01

    Most prolactin-secreting pituitary adenomas demonstrate slow growth and are effectively managed with medical/surgical therapy. Rarely, these tumors can behave aggressively with rapid growth and invasion of local tissues, and are refractory to medical, surgical, or radio-surgical therapies. We report a case of a prolactin-secreting adenoma in a young woman, which became progressively aggressive and refractory to usual treatment modalities, but responded to treatment with the chemotherapeutic agent temozolomide. In addition, we review the literature for treatment of refractory adenomas with temozolomide. The clinical and pathologic characteristics of aggressive prolactin-secreting adenomas are reviewed, as well as their response to dopamine agonists, surgery, radiotherapy, and chemotherapy. PMID:27489751

  17. Treatment of Aggressive Prolactin-Secreting Pituitary Adenomas with Adjuvant Temozolomide Chemotherapy: A Review.

    PubMed

    Moisi, Marc; Cruz, Aurora S; Benkers, Tara; Rostad, Steven; Broyles, Frances Broyles; Yuen, Kevin; Mayberg, Marc

    2016-01-01

    Most prolactin-secreting pituitary adenomas demonstrate slow growth and are effectively managed with medical/surgical therapy. Rarely, these tumors can behave aggressively with rapid growth and invasion of local tissues, and are refractory to medical, surgical, or radio-surgical therapies. We report a case of a prolactin-secreting adenoma in a young woman, which became progressively aggressive and refractory to usual treatment modalities, but responded to treatment with the chemotherapeutic agent temozolomide. In addition, we review the literature for treatment of refractory adenomas with temozolomide. The clinical and pathologic characteristics of aggressive prolactin-secreting adenomas are reviewed, as well as their response to dopamine agonists, surgery, radiotherapy, and chemotherapy.

  18. Profile of capecitabine/temozolomide combination in the treatment of well-differentiated neuroendocrine tumors

    PubMed Central

    Kotteas, Elias A; Syrigos, Konstantinos N; Saif, Muhammad Wasif

    2016-01-01

    Neuroendocrine tumors are a rare and heterogeneous group of tumors with a variety of primary origins and variable aggressiveness. Platinum-based chemotherapy has been the cornerstone of treatment for the poorly differentiated tumors. However, well-differentiated neuroendocrine tumors are quite chemoresistant and therapy options are limited. Octreotide analogs and tyrosine kinase inhibitors are widely acceptable treatments due to substantial efficacy and tolerable toxicity. On the contrary, monotherapy or combinations of the only approved cytotoxic agent streptozocin with other drugs have been almost abandoned because of excessive toxic events. In recent years, the combination of capecitabine and temozolomide has emerged as the most promising and efficacious treatment. The oral route of administration and the substantial improvement in the outcomes with manageable toxicity are the major advantages. We reviewed the current literature and presented the profile of the capecitabine/temozolomide combination in the management of well-differentiated neuroendocrine tumors. PMID:26929640

  19. Effect of Bevacizumab Plus Temozolomide-Radiotherapy for Newly Diagnosed Glioblastoma with Different MGMT Methylation Status: A Meta-Analysis of Clinical Trials

    PubMed Central

    Du, Chigang; Ren, Junquan; Zhang, Rui; Xin, Tao; Li, Zhongmin; Zhang, Zhiti; Xu, Xinghua; Pang, Qi

    2016-01-01

    Background MGMT methylation status can influence the therapeutic effect and prognosis of glioblastoma (GBM). There are conflicting results from studies evaluating the efficacy of bevacizumab (BV) when it is combined with temozolomide (TMZ) and radiotherapy (RT) in patients diagnosed with GBM with different MGMT methylation status. Material/Methods Data were extracted from publications in PubMed, Embase, and The Cochrane Library, with the last search performed March 23, 2016. Data on overall survival (OS), progression-free survival (PFS), and MGMT methylation status were obtained. Results Data from 3 clinical trials for a total of 1443 subjects were used for this meta-analysis. MGMT methylated and unmethylated patients showed improved PFS in the BV group (pooled HRs, 0.769, 95% CIs 0.604–0.978, P=0.032; 0.675, 95%CIs 0.466–0.979, P=0.038). For patients with either type of GBM, BV did not improve the OS based on the pooled HRs 1.132 (95% CIs 0.876–1.462; P=0.345) for methylated and 1.018 (95% CIs 0.879–1.179; P=0.345) for unmethylated. Conclusions Bevacizumab combined with temozolomide-radiotherapy correlated with improved PFS for treatment of patients with different MGMT methylation status of newly diagnosed GBM. There was insufficient evidence to determine the synergistic effects of combining BV with TMZ and RT on improving survival in patients with different MGMT methylation status. PMID:27684457

  20. Phase I Study Of The Poly(ADP-Ribose) Polymerase Inhibitor, AG014699, In Combination With Temozolomide in Patients with Advanced Solid Tumors

    PubMed Central

    Plummer, Ruth; Jones, Christopher; Middleton, Mark; Wilson, Richard; Evans, Jeffrey; Olsen, Anna; Curtin, Nicola; Boddy, Alan; McHugh, Peter; Newell, David; Harris, Adrian; Johnson, Patrick; Steinfeldt, Heidi; Dewji, Raz; Wang, Diane; Robson, Lesley; Calvert, Hilary

    2009-01-01

    Purpose One mechanism of tumor resistance to cytotoxic therapy is repair of damaged DNA. PARP-1 is a nuclear enzyme involved in base excision repair, one of the 5 major repair pathways. PARP inhibitors are emerging as a new class of agents which can potentiate chemo and radiotherapy. The paper reports safety, efficacy, pharmacokinetic and pharmacodynamic results of the First-in-Class trial of a PARP inhibitor, AG-014699, combined with temozolomide in adults with advanced malignancy. Experimental Design Initially patients with solid tumors received escalating doses of AG-014699 with 100 mg/m2 temozolomide daily x 5 q 28 to establish the PARP-inhibitory dose (PID). Subsequently AG-014699 dose was fixed at PID and temozolomide escalated to maximum tolerated dose or 200 mg/m2 in metastatic melanoma patients whose tumours were biopsied. AG014699 and temozolomide pharmacokinetics, PARP activity, DNA strand single strand breaks (SSB), response and toxicity were evaluated. Results 33 patients were enrolled. PARP inhibition was seen at all doses, PID was 12 mg/m2 based on 74 -97% inhibition of PBL PARP activity. Recommended doses were AG014699 12 mg/m2 and temozolomide 200 mg/m2. Mean tumor PARP inhibition at 5 hours was 92% (range 46 - 97%). No toxicity attributable to AG014699 alone was observed. AG014699 demonstrated linear pharmacokinetics with no interaction with temozolomide. All patients treated at PID showed increases in DNA SSB and encouraging evidence of activity was seen. Conclusions The combination of AG014699 and temozolomide is well tolerated, pharmacodynamic assessments demonstrating proof of principle of the mode of action of this new class of agents. PMID:19047122

  1. Imatinib in combination with hydroxyurea versus hydroxyurea alone as oral therapy in patients with progressive pretreated glioblastoma resistant to standard dose temozolomide.

    PubMed

    Dresemann, Gregor; Weller, Michael; Rosenthal, Mark A; Wedding, Ulrich; Wagner, Wolfgang; Engel, Erik; Heinrich, Bernhard; Mayer-Steinacker, Regine; Karup-Hansen, Anders; Fluge, Oystein; Nowak, Anna; Mehdorn, Maximilian; Schleyer, Eberhard; Krex, Dietmar; Olver, Ian N; Steinbach, Joachim P; Hosius, Christian; Sieder, Christian; Sorenson, Greg; Parker, Richard; Nikolova, Zariana

    2010-02-01

    A randomized, multicenter, open-label, phase 3 study of patients with progressive, recurrent glioblastoma multiforme (GBM) for whom front-line therapy had failed was conducted. This study was designed to determine whether combination therapy with imatinib and hydroxyurea (HU) has superior antitumor activity compared with HU monotherapy in the treatment of recurrent GBM. The target population consisted of patients with confirmed recurrent GBM and an Eastern Cooperative Oncology Group performance status of 0-2 who had completed previous treatment comprising surgical resection, irradiation therapy, and first-line chemotherapy (preferably temozolomide (TMZ) containing regimen) and who have progressed despite treatment. If first-line chemotherapy did not contain TMZ, a second completed chemotherapy was acceptable. The primary efficacy parameter was progression-free survival (PFS). The primary comparison of combination therapy versus monotherapy for PFS was not significant (adjusted P = 0.56). The hazard ratio (HR) (adjusted HR = 0.93) was not clinically relevant. The median PFS for the combination arm was low at 6 weeks and similar to the median PFS in the monotherapy arm (6 weeks). The 6-month PFS for the two treatment groups was very similar (5% in the combination arm vs. 7% in the monotherapy arm). No clinically meaningful differences were found between the two treatment arms, and the primary study end point was not met. Among the patients receiving imatinib, no adverse events were reported that were either previously unknown or unexpected as a consequence of the disease.

  2. Prediction of Response to Concurrent Chemoradiotherapy with Temozolomide in Glioblastoma: Application of Immediate Post-Operative Dynamic Susceptibility Contrast and Diffusion-Weighted MR Imaging

    PubMed Central

    Lee, Eun Kyoung; Yun, Tae Jin; Kang, Koung Mi; Kim, Tae Min; Lee, Se-Hoon; Park, Chul-Kee; Park, Sung-Hye; Kim, Il Han

    2015-01-01

    Objective To determine whether histogram values of the normalized apparent diffusion coefficient (nADC) and normalized cerebral blood volume (nCBV) maps obtained in contrast-enhancing lesions detected on immediate post-operative MR imaging can be used to predict the patient response to concurrent chemoradiotherapy (CCRT) with temozolomide (TMZ). Materials and Methods Twenty-four patients with GBM who had shown measurable contrast enhancement on immediate post-operative MR imaging and had subsequently undergone CCRT with TMZ were retrospectively analyzed. The corresponding histogram parameters of nCBV and nADC maps for measurable contrast-enhancing lesions were calculated. Patient groups with progression (n = 11) and non-progression (n = 13) at one year after the operation were identified, and the histogram parameters were compared between the two groups. Receiver operating characteristic (ROC) analysis was used to determine the best cutoff value for predicting progression. Progression-free survival (PFS) was determined with the Kaplan-Meier method and the log-rank test. Results The 99th percentile of the cumulative nCBV histogram (nCBV C99) on immediate post-operative MR imaging was a significant predictor of one-year progression (p = 0.033). ROC analysis showed that the best cutoff value for predicting progression after CCRT was 5.537 (sensitivity and specificity were 72.7% and 76.9%, respectively). The patients with an nCBV C99 of < 5.537 had a significantly longer PFS than those with an nCBV C99 of ≥ 5.537 (p = 0.026). Conclusion The nCBV C99 from the cumulative histogram analysis of the nCBV from immediate post-operative MR imaging may be feasible for predicting glioblastoma response to CCRT with TMZ. PMID:26576125

  3. Microvesicles as a Biomarker for Tumor Progression versus Treatment Effect in Radiation/Temozolomide-Treated Glioblastoma Patients

    PubMed Central

    Koch, Cameron J.; Lustig, Robert A.; Yang, Xiang-Yang; Jenkins, Walter T.; Wolf, Ronald L.; Martinez-Lage, Maria; Desai, Arati; Williams, Dewight; Evans, Sydney M.

    2014-01-01

    The standard of care for glioblastoma (GB) is surgery followed by concurrent radiation therapy (RT) and temozolomide (TMZ) and then adjuvant TMZ. This regime is associated with increased survival but also increased occurrence of equivocal imaging findings, e.g., tumor progression (TP) versus treatment effect (TE), which is also referred to as pseudoprogression (PsP). Equivocal findings make decisions regarding further treatment difficult and often delayed. Because none of the current imaging assays have proven sensitive and specific for differentiation of TP versus TE/PsP, we investigated whether blood-derived microvesicles (MVs) would be a relevant assay. METHODS: 2.8 ml of citrated blood was collected from patients with GB at the time of their RT simulation, at the end of chemoradiation therapy (CRT), and multiple times following treatment. MVs were collected following multiple centrifugations (300g, 2500g, and 15,000g). The pellet from the final spin was analyzed using flow cytometry. A diameter of approximately 300 nm or greater and Pacific Blue–labeled Annexin V positivity were used to identify the MVs reported herein. RESULTS: We analyzed 19 blood samples from 11 patients with GB. MV counts in the patients with stable disease or TE/PsP were significantly lower than patients who developed TP (P = .014). CONCLUSION: These preliminary data suggest that blood analysis for MVs from GB patients receiving CRT may be useful to distinguish TE/PsP from TP. MVs may add clarity to standard imaging for decision making in patients with equivocal imaging findings. PMID:25500085

  4. Polymer Nanocomposites Based Thermo-Sensitive Gel for Paclitaxel and Temozolomide Co-Delivery to Glioblastoma Cells.

    PubMed

    Xu, Yuanyuan; Shen, Ming; Sun, Ying; Gao, Pei; Duan, Yourong

    2015-12-01

    In this work, we have reported the preparation and optimization of paclitaxel (PTX) and temozolomide (TMZ) loaded monomethoxy (polyethylene glycol)-poly(D, L-lactide-co-glycolide) (mPEG-PLGA) nanocomposite which is a thermo-sensitive gel delivery system to glioblastoma. We utilized the orthogonal design and homogeneous design for the optimal drug-loaded nanoparticles (NPs) and composite gel prescription, respectively. The physicochemical characteristics of NPs and rheological properties of the gel were analyzed. Then the in vitro release of the gel was determined with a membrane-less diffusion system. Finally, the cytotoxic and apoptosis-inducing effects of the gel on the human malignant glioblastoma cell line U87 and C6 rat glioblastoma cell line were evaluated by MTT and flow cytometry apoptosis assay, respectively. The transmission electron microscopy (TEM) analysis revealed the optimized NPs with a relatively uniform diameter and distribution. The homogeneous design and rheological determination showed that the optimized gel prescription was 250 mg/mL Pluronic F127 (F127), 0.5% hydroxy propyl methylcellulose (HPMC-100M), 0.5% Pluronic F68 (F68), 0.5% sodium alginate (SA) and suitable NPs, which possessed the appropriate gelation behaviors: gelation temperature 28.01 degrees C, gelation time 127.1 s and corrosion speed 0.1892 g/cm2 x hr; and rheological properties: suitable elasticity modulus, viscosity modulus and low phase angle. The in vitro results suggested that the PTX and TMZ were sustainedly released from nanoparticles or the composite gel, and the release and elimination time greatly prolonged; and the composite gel possessed much higher growth-inhibiting effect and apoptosis-inducing rate in U87 and C6 cells than other formulations. These findings demonstrated that the optimal gel was a promising delivery system for the interstitial chemotherapy to glioblastoma. PMID:26682412

  5. MicroRNA-93 promotes the malignant phenotypes of human glioma cells and induces their chemoresistance to temozolomide

    PubMed Central

    Chen, Rui; Liu, Huan; Cheng, Quan; Jiang, Bing; Peng, Renjun; Zou, Qin; Yang, Wenren; Yang, Xiaosheng; Wu, Xiaobing; Chen, Zigui

    2016-01-01

    ABSTRACT MicroRNAs (miRNAs), a class of small non-coding RNAs, can induce mRNA degradation or repress translation by binding to the 3′-untranslated region (UTR) of its target mRNA. Recently, some specific miRNAs, e.g. miR-93, have been found to be involved in pathological processes by targeting some oncogenes or tumor suppressors in glioma. However, the regulatory mechanism of miR-93 in the biological behaviors and chemoresistance of glioma cells remains unclear. In the present study, in situ hybridization and real-time RT-PCR data indicated that miR-93 was significantly upregulated in glioma patients (n=43) compared with normal brain tissues (n=8). Moreover, the upregulated miR-93 level was significantly associated with the advanced malignancy. We also found that upregulation of miR-93 promoted the proliferation, migration and invasion of glioma cells, and that miR-93 was involved in the regulation of cell cycle progression by mediating the protein levels of P21, P27, P53 and Cyclin D1. P21 was further identified as a direct target of miR-93. Knockdown of P21 attenuated the suppressive effects of miR-93 inhibition on cell cycle progression and colony formation. In addition, inhibition of miR-93 enhanced the chemosensitization of glioma cells to temozolomide (TMZ). Based on these above data, our study demonstrates that miR-93, upregulated in glioma, promotes the proliferation, cell cycle progression, migration and invasion of human glioma cells and suppresses their chemosensitivity to TMZ. Therefore, miR-93 may become a promising diagnostic marker and therapeutic target for glioma. PMID:27185265

  6. Temozolomide-perillyl alcohol conjugate induced reactive oxygen species accumulation contributes to its cytotoxicity against non-small cell lung cancer

    PubMed Central

    Song, Xingguo; Xie, Li; Wang, Xingwu; Zeng, Qian; Chen, Thomas C.; Wang, Weijun; Song, Xianrang

    2016-01-01

    Temozolomide-perillyl alcohol conjugate (TMZ − POH), a novel temozolomide analog, was reported to play a cytotoxic role in triple-negative breast cancer and TMZ-resistant gliomas. In a current study we had demonstrated how TMZ − POH also exhibited its cytotoxicity against non-small cell lung cancer (NSCLC), the most common type of lung cancer, as evidence from cell/tumor proliferation inhibition, G2/M arrest, DNA damage and mitochondrial apoptosis. Importantly, TMZ − POH’s cytotoxicity is closely related to reactive oxygen species (ROS) accumulation because it can be reversed by two ROS scavengers, catalase (CAT) and N-acetyl-L-cysteine (NAC). TMZ − POH induces mitochondrial transmembrane potential (MTP) decrease and ROS accumulation, in turn activates mitogen-activated protein kinase (MAPKs) signaling and mitochondrial apoptosis, and then exerts its cytotoxicity, thus proposing TMZ − POH as a potential therapeutic candidate for NSCLC. PMID:26949038

  7. The Microarray Gene Profiling Analysis of Glioblastoma Cancer Cells Reveals Genes Affected by FAK Inhibitor Y15 and Combination of Y15 and Temozolomide

    PubMed Central

    Huang, Grace; Ho, Baotran; Conroy, Jeffrey; Liu, Song; Qiang, Hu; Golubovskaya, Vita

    2013-01-01

    Focal adhesion is known to be highly expressed and activated in glioma cells. Recently, we demonstrated that FAK autophosphorylation inhibitor, Y15 significantly decreased tumor growth of DBTRG and U87 cells, especially in combination with temozolomide. In the present report, we performed gene expression analysis in these cells to reveal genes affected by Y15, temozolomide and combination of Y15 and temozolomide. We tested the effect of Y15 on gene expression by Illumina Human HT12v4 microarray assay and detected 8087 and 6555 genes, which were significantly either up- or down-regulated by Y15-treatment in DBTRG and U87 cells, respectively (p<0.05). Moreover, DBTRG and U87 cells treated with Y15 changed expression of 1332 and 462 genes more than 1.5 fold, p<0.05, respectively and had 237 common genes affected by Y15. The common genes up-regulated by Y15 included GADD45A, HSPA6 (heat-shock 70); DUSP1, DUSP 5 (dual-phosphatase 5); CDKN1A (p21) and common down-regulated genes included kinesins, such as KIF11, 14, 20A, 20B; topoisomerase II, TOP2A; cyclin F; cell cycle protein: BUB1; PARP1, POLA1. In addition, we detected genes affected by temozolomide and by combination of Y15 and temozolomide treatment in U87 cells. Among genes up-regulated by Y15 and temozolomide more significantly than by each agent alone were: COX7B; interferon, gamma-inducible transcript: IFI16; DDIT4; GADD45G and down-regulated: KIF3A, AKT1; ABL; JAK1, GLI3 and ALDH1A3. Thus, microarray gene expression analysis can be effective in establishing genes affected in response to FAK inhibitor alone and in response to combination of Y15 with temozolomide that is important for glioblastoma therapy. PMID:23387973

  8. B-Raf inhibitor vemurafenib in combination with temozolomide and fotemustine in the killing response of malignant melanoma cells

    PubMed Central

    Krumm, Andrea; Merz, Stephanie; Switzeny, Olivier Jérôme; Christmann, Markus; Loquai, Carmen; Kaina, Bernd

    2014-01-01

    In the treatment of metastatic melanoma, a highly therapy-refractory cancer, alkylating agents are used and, for the subgroup of BRAFV600E cancers, the B-Raf inhibitor vemurafenib. Although vemurafenib is initially beneficial, development of drug resistance occurs leading to tumor relapse, which necessitates the requirement for combined or sequential therapy with other drugs, including genotoxic alkylating agents. This leads to the question whether vemurafenib and alkylating agents act synergistically and whether chronic vemurafenib treatment alters the melanoma cell response to alkylating agents. Here we show that a) BRAFV600E melanoma cells are killed by vemurafenib, driving apoptosis, b) BRAFV600E melanoma cells are neither more resistant nor sensitive to temozolomide/fotemustine than non-mutant cells, c) combined treatment with vemurafenib plus temozolomide or fotemustine has an additive effect on cell kill, d) acquired vemurafenib resistance of BRAFV600E melanoma cells does not affect MGMT, MSH2, MSH6, PMS2 and MLH1, nor does it affect the resistance to temozolomide and fotemustine, e) metastatic melanoma biopsies obtained from patients prior to and after vemurafenib treatment did not show a change in the MGMT promoter methylation status and MGMT expression level. The data suggest that consecutive treatment with vemurafenib and alkylating drugs is a reasonable strategy for metastatic melanoma treatment. PMID:25557167

  9. Immunological responses in a patient with glioblastoma multiforme treated with sequential courses of temozolomide and immunotherapy: Case study

    PubMed Central

    Heimberger, Amy B.; Sun, Wei; Hussain, S. Farzana; Dey, Mahua; Crutcher, Lamonne; Aldape, Ken; Gilbert, Mark; Hassenbusch, Samuel J.; Sawaya, Raymond; Schmittling, Bob; Archer, Gary E.; Mitchell, Duane A.; Bigner, Darell D.; Sampson, John H.

    2008-01-01

    Cytotoxic chemotherapy that induces lymphopenia is predicted to ablate the benefits of active antitumor immunization. Temozolomide is an effective chemo-therapeutic agent for patients with glioblastoma multiforme, but it induces significant lymphopenia. Although there is monthly fluctuation of the white blood cell count, specifically the CD4 and CD8 counts, there was no cumulative decline in the patient described in this case report. Depriving patients of this agent, in order to treat with immunotherapy, is controversial. Despite conventional dogma, we demonstrated that chemotherapy and immunotherapy can be delivered concurrently without negating the effects of immunotherapy. In fact, the temozolomide-induced lymphopenia may prove to be synergistic with a peptide vaccine secondary to inhibition of regulatory T cells or their delayed recovery. PMID:18079360

  10. Radiotherapy and temozolomide for anaplastic astrocytic gliomas

    PubMed Central

    Nayak, Lakshmi; Panageas, Katherine S.; Reiner, Anne S.; Huse, Jason T.; Pentsova, Elena; Braunthal, Stephanie G.; Abrey, Lauren E.; DeAngelis, Lisa M.

    2015-01-01

    We previously reported results of a phase II non-comparative trial that randomized patients with glioblastoma following radiotherapy to one of two different temozolomide schedules, followed by 13-cis-retinoic acid (RA) maintenance. Here we report the results of an exploratory cohort of patients accrued with anaplastic astrocytic tumors. Patients with newly diagnosed anaplastic astrocytoma (AA) or anaplastic oligo-astrocytoma (AOA) were treated with concurrent radiotherapy (60 Gy over 6 weeks) and temozolomide (75 mg/m2), and six adjuvant 28-day cycles of either dose-dense (150 mg/m2, days 1–7, 15–21) or metronomic (50 mg/m2, days 1–28) temozolomide. Subsequently, maintenance RA (100 mg/m2, days 1–21/28) was administered until disease progression. All outcome measures were descriptive without intention to compare between treatment arms. Survival was measured by the Kaplan–Meier method. There were 31 patients (21 men, 10 women) with median age 48 years (range 28–74), median KPS 90 (range 60–100). Extent of resection was gross-total in 35 %, subtotal 23 %, and biopsy 42 %. Histology was AA in 90 %, and AOA in 10 %. MGMT promoter methylation was methylated in 20 %, unmethylated in 50 %, and uninformative in 30 % of 30 tested. Median progression-free survival was 2.1 years (95 % CI 0.95–Not Reached), and overall survival 2.9 years (95 % CI 2.0–Not Reached). We report outcomes among a homogeneously treated population with anaplastic astrocytic tumors. Survival was unexpectedly short compared to other reports. These data may be useful as a contemporary historic control for other ongoing or future randomized trials. PMID:25920709

  11. Radiotherapy and temozolomide for anaplastic astrocytic gliomas.

    PubMed

    Nayak, Lakshmi; Panageas, Katherine S; Reiner, Anne S; Huse, Jason T; Pentsova, Elena; Braunthal, Stephanie G; Abrey, Lauren E; DeAngelis, Lisa M; Lassman, Andrew B

    2015-05-01

    We previously reported results of a phase II non-comparative trial that randomized patients with glioblastoma following radiotherapy to one of two different temozolomide schedules, followed by 13-cis-retinoic acid (RA) maintenance. Here we report the results of an exploratory cohort of patients accrued with anaplastic astrocytic tumors. Patients with newly diagnosed anaplastic astrocytoma (AA) or anaplastic oligo-astrocytoma (AOA) were treated with concurrent radiotherapy (60 Gy over 6 weeks) and temozolomide (75 mg/m(2)), and six adjuvant 28-day cycles of either dose-dense (150 mg/m(2), days 1-7, 15-21) or metronomic (50 mg/m(2), days 1-28) temozolomide. Subsequently, maintenance RA (100 mg/m(2), days 1-21/28) was administered until disease progression. All outcome measures were descriptive without intention to compare between treatment arms. Survival was measured by the Kaplan-Meier method. There were 31 patients (21 men, 10 women) with median age 48 years (range 28-74), median KPS 90 (range 60-100). Extent of resection was gross-total in 35%, subtotal 23%, and biopsy 42%. Histology was AA in 90%, and AOA in 10%. MGMT promoter methylation was methylated in 20%, unmethylated in 50%, and uninformative in 30% of 30 tested. Median progression-free survival was 2.1 years (95% CI 0.95-Not Reached), and overall survival 2.9 years (95 % CI 2.0-Not Reached). We report outcomes among a homogeneously treated population with anaplastic astrocytic tumors. Survival was unexpectedly short compared to other reports. These data may be useful as a contemporary historic control for other ongoing or future randomized trials. PMID:25920709

  12. Phase 2 Trial of Hypofractionated High-Dose Intensity Modulated Radiation Therapy With Concurrent and Adjuvant Temozolomide for Newly Diagnosed Glioblastoma

    SciTech Connect

    Iuchi, Toshihiko; Hatano, Kazuo; Kodama, Takashi; Sakaida, Tsukasa; Yokoi, Sana; Kawasaki, Koichiro; Hasegawa, Yuzo; Hara, Ryusuke

    2014-03-15

    Purpose/Objectives: To assess the effect and toxicity of hypofractionated high-dose intensity modulated radiation therapy (IMRT) with concurrent and adjuvant temozolomide (TMZ) in 46 patients with newly diagnosed glioblastoma multiforme (GBM). Methods and Materials: All patients underwent postsurgical hypofractionated high-dose IMRT. Three layered planning target volumes (PTVs) were contoured. PTV1 was the surgical cavity and residual tumor on T1-weighted magnetic resonance images with 5-mm margins, PTV2 was the area with 15-mm margins surrounding the PTV1, and PTV3 was the high-intensity area on fluid-attenuated inversion recovery images. Irradiation was performed in 8 fractions at total doses of 68, 40, and 32 Gy for PTV1, PTV2, and PTV3, respectively. Concurrent TMZ was given at 75 mg/m{sup 2}/day for 42 consecutive days. Adjuvant TMZ was given at 150 to 200 mg/m{sup 2}/day for 5 days every 28 days. Overall and progression-free survivals were evaluated. Results: No acute IMRT-related toxicity was observed. The dominant posttreatment failure pattern was dissemination. During a median follow-up time of 16.3 months (range, 4.3-80.8 months) for all patients and 23.7 months (range, 12.4-80.8 months) for living patients, the median overall survival was 20.0 months after treatment. Radiation necrosis was diagnosed in 20 patients and was observed not only in the high-dose field but also in the subventricular zone (SVZ). Necrosis in the SVZ was significantly correlated with prolonged survival (hazard ratio, 4.08; P=.007) but caused deterioration in the performance status of long-term survivors. Conclusions: Hypofractionated high-dose IMRT with concurrent and adjuvant TMZ altered the dominant failure pattern from localized to disseminated and prolonged the survival of patients with GBM. Necrosis in the SVZ was associated with better patient survival, but the benefit of radiation to this area remains controversial.

  13. PTEN loss compromises homologous recombination repair in astrocytes: implications for GBM therapy with temozolomide or PARP inhibitors

    PubMed Central

    McEllin, Brian; Camacho, Cristel V.; Mukherjee, Bipasha; Hahm, Brandon; Tomimatsu, Nozomi; Bachoo, Robert M.; Burma, Sandeep

    2010-01-01

    Glioblastoma multiforme (GBM) are lethal brain tumors that are highly resistant to therapy. The only meaningful improvement in therapeutic response came from use of the SN1-type alkylating agent, temozolomide, in combination with ionizing radiation (IR). However, no genetic markers that might predict a better response to DNA alkylating agents have been identified in GBMs, except for loss of O6-methylguanine-DNA methyltransferase (MGMT) via promoter methylation. In this study, using genetically defined primary murine astrocytes as well as human glioma lines, we show that loss of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) confers sensitivity to N-methyl-N′-nitro-N-nitrosoguanidine (MNNG), a functional analog of temozolomide. We find that MNNG induces replication-associated DNA double-strand breaks (DSBs) that are inefficiently repaired in PTEN-deficient astrocytes and trigger apoptosis. Mechanistically, this is because PTEN-null astrocytes are compromised in homologous recombination (HR), which is important for the repair of replication-associated DSBs. Our results suggest that reduced levels of Rad51 paralogs in PTEN-null astrocytes might underlie the HR deficiency of these cells. Importantly, the HR deficiency of PTEN-null cells renders them sensitive to the poly(ADP-ribose) polymerase (PARP) inhibitor ABT-888 due to synthetic lethality. In sum, our results tentatively suggest that patients with PTEN-null GBMs (about 36%) may especially benefit from treatment with DNA alkylating agents such as temozolomide. Significantly, our results also provide a rational basis for treating the sub-group of patients who are PTEN deficient with PARP inhibitors in addition to the current treatment regimen of radiation and temozolomide. PMID:20530668

  14. Phase 2 Study of Temozolomide-based Chemoradiation Therapy for High-risk Low-grade Gliomas: Preliminary Results of Radiation Therapy Oncology Group 0424

    PubMed Central

    Fisher, Barbara J.; Hu, Chen; Macdonald, David R.; Lesser, Glenn J.; Coons, Stephen W.; Brachman, David G.; Ryu, Samuel; Werner-Wasik, Maria; Bahary, Jean-Paul; Liu, Junfeng; Chakravarti, Arnab; Mehta, Minesh

    2015-01-01

    Purpose Radiation Therapy Oncology Group (RTOG) 0424 was a phase 2 study of a high-risk low-grade glioma (LGG) population who were treated with temozolomide (TMZ) and radiation therapy (RT), and outcomes were compared to those of historical controls. This study was designed to detect a 43% increase in median survival time (MST) from 40.5 to 57.9 months and a 20% improvement in 3-year overall survival (OS) rate from 54% to 65% at a 10% significance level (1-sided) and 96% power. Methods and Materials Patients with LGGs with fewer than 3 risk factors for recurrence (age ≥40 years, astrocytoma histology, bihemispherical tumor, preoperative tumor diameter of ≥6 cm, or a preoperative neurological function status of >1) were treated with RT (54 Gy in 30 fractions) and concurrent and adjuvant TMZ. Results From 2005 to 2009, 129 evaluable patients (75 males and 54 females) were accrued. Median age was 49 years; 91% had a Zubrod score of 0 or 1; and 69%, 25%, and 6% of patients had 3, 4, and 5 risk factors, respectively. Patients had median and minimum follow-up examinations of 4.1 years and 3 years, respectively. The 3-year OS rate was 73.1% (95% confidence interval: 65.3%–80.8%), which was significantly improved compared to that of prespecified historical control values (P<.01). Median survival time has not yet been reached. Three-year progression-free survival was 59.2%. Grades 3 and 4 adverse events occurred in 43% and 10% of patients, respectively. One patient died of herpes encephalitis. Conclusions The 3-year OS rate of 73.1% for RTOG 0424 high-risk LGG patients is higher than that reported for historical controls (P<.001) and the study-hypothesized rate of 65%. PMID:25680596

  15. MGMT Gene Promoter Methylation as a Potent Prognostic Factor in Glioblastoma Treated With Temozolomide-Based Chemoradiotherapy: A Single-Institution Study

    SciTech Connect

    Kim, Young Suk; Kim, Se Hoon; Cho, Jaeho; Kim, Jun Won; Chang, Jong Hee; Kim, Dong Suk; Lee, Kyu Sung; Suh, Chang-Ok

    2012-11-01

    Purpose: Recently, cells deficient in O{sup 6}-methylguanine-DNA methyltransferase (MGMT) were found to show increased sensitivity to temozolomide (TMZ). We evaluated whether hypermethylation of MGMT was associated with survival in patients with glioblastoma multiforme (GBM). Methods and Materials: We retrospectively analyzed 93 patients with histologically confirmed GBM who received involved-field radiotherapy with TMZ from 2001 to 2008. The median age was 58 years (range, 24-78 years). Surgical resection was total in 39 patients (42%), subtotal in 30 patients (32%), and partial in 17 patients (18%); only a biopsy was performed in 7 patients (8%). Postoperative radiotherapy began within 3 weeks of surgery in 87% of the patients. Radiotherapy doses ranged from 50 to 74 Gy (median, 70 Gy). MGMT gene methylation was determined in 78 patients; MGMT was unmethylated in 43 patients (55%) and methylated in 35 patients (45%). The median follow-up period was 22 months (range, 3-88 months) for all patients. Results: The median overall survival (OS) was 22 months, and progression-free survival (PFS) was 11 months. MGMT gene methylation was an independently significant prognostic factor for both OS (p = 0.002) and PFS (p = 0.008) in multivariate analysis. The median OS was 29 months for the methylated group and 20 months for the unmethylated group. In 35 patients with methylated MGMT genes, the 2-year and 5-year OS rates were 54% and 31%, respectively. Six patients with combined prognostic factors of methylated MGMT genes, age {<=}50 years, and total/subtotal resections are all alive 38 to 77 months after operation, whereas the median OS in 8 patients with unmethylated MGMT genes, age >50 years, and less than subtotal resection was 13.2 months. Conclusion: We confirmed that MGMT gene methylation is a potent prognostic factor in patients with GBM. Our results suggest that early postoperative radiotherapy and a high total/subtotal resection rate might further improve the

  16. Health-Related Quality of Life in Elderly Patients With Newly Diagnosed Glioblastoma Treated With Short-Course Radiation Therapy Plus Concomitant and Adjuvant Temozolomide

    SciTech Connect

    Minniti, Giuseppe; Scaringi, Claudia; Baldoni, Alessandra; Lanzetta, Gaetano; De Sanctis, Vitaliana; Esposito, Vincenzo; Enrici, Riccardo Maurizi

    2013-06-01

    Purpose: To describe the quality of life (QOL) in elderly patients with glioblastoma (GBM) treated with an abbreviated course of radiation therapy (RT; 40 Gy in 15 fractions) plus concomitant and adjuvant temozolomide (TMZ). Methods and Materials: Health-related QOL (HRQOL) was assessed by European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core-30 (QLQ-C30, version 3) and EORTC Quality of Life Questionnaire Brain Cancer Module (QLQ-BN20). Changes from baseline in the score of 9 preselected domains (global QLQ, social functioning, cognitive functioning, emotional functioning, physical functioning, motor dysfunction, communication deficit, fatigue, insomnia) were determined 4 weeks after RT and thereafter every 8 weeks during the treatment until disease progression. The proportion of patients with improved HRQOL scores, defined as a change of 10 points or more, and duration of changes were recorded. Results: Sixty-five patients completed the questionnaires at baseline. The treatment was consistently associated with improvement or stability in most of the preselected HRQOL domains. Global health improved over time; mean score differed by 9.6 points between baseline and 6-month follow-up (P=.03). For social functioning and cognitive functioning, mean scores improved over time, with a maximum difference of 10.4 points and 9.5 points between baseline and 6-month follow-up (P=.01 and P=.02), respectively. By contrast, fatigue worsened over time, with a difference in mean score of 5.6 points between baseline and 4-month follow-up (P=.02). Conclusions: A short course of RT in combination with TMZ in elderly patients with GBM was associated with survival benefit without a negative effect on HRQOL until the time of disease progression.

  17. Phase 2 Study of Temozolomide-Based Chemoradiation Therapy for High-Risk Low-Grade Gliomas: Preliminary Results of Radiation Therapy Oncology Group 0424

    SciTech Connect

    Fisher, Barbara J.; Hu, Chen; Macdonald, David R.; Lesser, Glenn J.; Coons, Stephen W.; Brachman, David G.; Ryu, Samuel; Werner-Wasik, Maria; Bahary, Jean-Paul; Liu, Junfeng; Chakravarti, Arnab; Mehta, Minesh

    2015-03-01

    Purpose: Radiation Therapy Oncology Group (RTOG) 0424 was a phase 2 study of a high-risk low-grade glioma (LGG) population who were treated with temozolomide (TMZ) and radiation therapy (RT), and outcomes were compared to those of historical controls. This study was designed to detect a 43% increase in median survival time (MST) from 40.5 to 57.9 months and a 20% improvement in 3-year overall survival (OS) rate from 54% to 65% at a 10% significance level (1-sided) and 96% power. Methods and Materials: Patients with LGGs with 3 or more risk factors for recurrence (age ≥40 years, astrocytoma histology, bihemispherical tumor, preoperative tumor diameter of ≥6 cm, or a preoperative neurological function status of >1) were treated with RT (54 Gy in 30 fractions) and concurrent and adjuvant TMZ. Results: From 2005 to 2009, 129 evaluable patients (75 males and 54 females) were accrued. Median age was 49 years; 91% had a Zubrod score of 0 or 1; and 69%, 25%, and 6% of patients had 3, 4, and 5 risk factors, respectively. Patients had median and minimum follow-up examinations of 4.1 years and 3 years, respectively. The 3-year OS rate was 73.1% (95% confidence interval: 65.3%-80.8%), which was significantly improved compared to that of prespecified historical control values (P<.001). Median survival time has not yet been reached. Three-year progression-free survival was 59.2%. Grades 3 and 4 adverse events occurred in 43% and 10% of patients, respectively. One patient died of herpes encephalitis. Conclusions: The 3-year OS rate of 73.1% for RTOG 0424 high-risk LGG patients is higher than that reported for historical controls (P<.001) and the study-hypothesized rate of 65%.

  18. EGFR inhibition in glioma cells modulates Rho signaling to inhibit cell motility and invasion and cooperates with temozolomide to reduce cell growth.

    PubMed

    Ramis, Guillem; Thomàs-Moyà, Elena; Fernández de Mattos, Silvia; Rodríguez, José; Villalonga, Priam

    2012-01-01

    Enforced EGFR activation upon gene amplification and/or mutation is a common hallmark of malignant glioma. Small molecule EGFR tyrosine kinase inhibitors, such as erlotinib (Tarceva), have shown some activity in a subset of glioma patients in recent trials, although the reported data on the cellular basis of glioma cell responsiveness to these compounds have been contradictory. Here we have used a panel of human glioma cell lines, including cells with amplified or mutant EGFR, to further characterize the cellular effects of EGFR inhibition with erlotinib. Dose-response and cellular growth assays indicate that erlotinib reduces cell proliferation in all tested cell lines without inducing cytotoxic effects. Flow cytometric analyses confirm that EGFR inhibition does not induce apoptosis in glioma cells, leading to cell cycle arrest in G(1). Interestingly, erlotinib also prevents spontaneous multicellular tumour spheroid growth in U87MG cells and cooperates with sub-optimal doses of temozolomide (TMZ) to reduce multicellular tumour spheroid growth. This cooperation appears to be schedule-dependent, since pre-treatment with erlotinib protects against TMZ-induced cytotoxicity whereas concomitant treatment results in a cooperative effect. Cell cycle arrest in erlotinib-treated cells is associated with an inhibition of ERK and Akt signaling, resulting in cyclin D1 downregulation, an increase in p27(kip1) levels and pRB hypophosphorylation. Interestingly, EGFR inhibition also perturbs Rho GTPase signaling and cellular morphology, leading to Rho/ROCK-dependent formation of actin stress fibres and the inhibition of glioma cell motility and invasion.

  19. Microenvironmental Modulation of Decorin and Lumican in Temozolomide-Resistant Glioblastoma and Neuroblastoma Cancer Stem-Like Cells.

    PubMed

    Farace, Cristiano; Oliver, Jaime Antonio; Melguizo, Consolacion; Alvarez, Pablo; Bandiera, Pasquale; Rama, Ana Rosa; Malaguarnera, Giulia; Ortiz, Raul; Madeddu, Roberto; Prados, Jose

    2015-01-01

    The presence of cancer stem cells (CSCs) or tumor-initiating cells can lead to cancer recurrence in a permissive cell-microenvironment interplay, promoting invasion in glioblastoma (GBM) and neuroblastoma (NB). Extracellular matrix (ECM) small leucine-rich proteoglycans (SLRPs) play multiple roles in tissue homeostasis by remodeling the extracellular matrix (ECM) components and modulating intracellular signaling pathways. Due to their pan-inhibitory properties against receptor tyrosine kinases (RTKs), SLRPs are reported to exert anticancer effects in vitro and in vivo. However, their roles seem to be tissue-specific and they are also involved in cancer cell migration and drug resistance, paving the way to complex different scenarios. The aim of this study was to determine whether the SLRPs decorin (DCN) and lumican (LUM) are recruited in cell plasticity and microenvironmental adaptation of differentiated cancer cells induced towards stem-like phenotype. Floating neurospheres were generated by applying CSC enrichment medium (neural stem cell serum-free medium, NSC SFM) to the established SF-268 and SK-N-SH cancer cell lines, cellular models of GBM and NB, respectively. In both models, the time-dependent synergistic activation of DCN and LUM was observed. The highest DCN and LUM mRNA/protein expression was detected after cell exposure to NSC SFM for 8/12 days, considering these cells as SLRP-expressing (SLRP+) CSC-like. Ultrastructural imaging showed the cellular heterogeneity of both the GBM and NB neurospheres and identified the inner living cells. Parental cell lines of both GBM and NB grew only in soft agar + NSC SFM, whereas the secondary neurospheres (originated from SLRP+ t8 CSC-like) showed lower proliferation rates than primary neurospheres. Interestingly, the SLRP+ CSC-like from the GBM and NB neurospheres were resistant to temozolomide (TMZ) at concentrations >750 μM. Our results suggest that GBM and NB CSC-like promote the activation of huge quantities

  20. Microenvironmental Modulation of Decorin and Lumican in Temozolomide-Resistant Glioblastoma and Neuroblastoma Cancer Stem-Like Cells

    PubMed Central

    Melguizo, Consolacion; Alvarez, Pablo; Bandiera, Pasquale; Rama, Ana Rosa; Malaguarnera, Giulia; Ortiz, Raul; Madeddu, Roberto; Prados, Jose

    2015-01-01

    The presence of cancer stem cells (CSCs) or tumor-initiating cells can lead to cancer recurrence in a permissive cell–microenvironment interplay, promoting invasion in glioblastoma (GBM) and neuroblastoma (NB). Extracellular matrix (ECM) small leucine-rich proteoglycans (SLRPs) play multiple roles in tissue homeostasis by remodeling the extracellular matrix (ECM) components and modulating intracellular signaling pathways. Due to their pan-inhibitory properties against receptor tyrosine kinases (RTKs), SLRPs are reported to exert anticancer effects in vitro and in vivo. However, their roles seem to be tissue-specific and they are also involved in cancer cell migration and drug resistance, paving the way to complex different scenarios. The aim of this study was to determine whether the SLRPs decorin (DCN) and lumican (LUM) are recruited in cell plasticity and microenvironmental adaptation of differentiated cancer cells induced towards stem-like phenotype. Floating neurospheres were generated by applying CSC enrichment medium (neural stem cell serum-free medium, NSC SFM) to the established SF-268 and SK-N-SH cancer cell lines, cellular models of GBM and NB, respectively. In both models, the time-dependent synergistic activation of DCN and LUM was observed. The highest DCN and LUM mRNA/protein expression was detected after cell exposure to NSC SFM for 8/12 days, considering these cells as SLRP-expressing (SLRP+) CSC-like. Ultrastructural imaging showed the cellular heterogeneity of both the GBM and NB neurospheres and identified the inner living cells. Parental cell lines of both GBM and NB grew only in soft agar + NSC SFM, whereas the secondary neurospheres (originated from SLRP+ t8 CSC-like) showed lower proliferation rates than primary neurospheres. Interestingly, the SLRP+ CSC-like from the GBM and NB neurospheres were resistant to temozolomide (TMZ) at concentrations >750 μM. Our results suggest that GBM and NB CSC-like promote the activation of huge quantities

  1. Phase 1/2 Trials of Temozolomide, Motexafin Gadolinium, and 60-Gy Fractionated Radiation for Newly Diagnosed Supratentorial Glioblastoma Multiforme: Final Results of RTOG 0513

    SciTech Connect

    Brachman, David G.; Pugh, Stephanie L.; Ashby, Lynn S.; Thomas, Theresa A.; Dunbar, Erin M.; Narayan, Samir; Robins, H. Ian; Bovi, Joseph A.; Rockhill, Jason K.; Won, Minhee; Curran, Walter P.

    2015-04-01

    Purpose: The purpose of phase 1 was to determine the maximum tolerated dose (MTD) of motexafin gadolinium (MGd) given concurrently with temozolomide (TMZ) and radiation therapy (RT) in patients with newly diagnosed supratentorial glioblastoma multiforme (GBM). Phase 2 determined whether this combination improved overall survival (OS) and progression-free survival (PFS) in GBM recursive partitioning analysis class III to V patients compared to therapies for recently published historical controls. Methods and Materials: Dose escalation in phase 1 progressed through 3 cohorts until 2 of 6 patients experienced dose-limiting toxicity or a dose of 5 mg/kg was reached. Once MTD was established, a 1-sided 1-sample log-rank test at significance level of .1 had 85% power to detect a median survival difference (13.69 vs 18.48 months) with 60 deaths over a 12-month accrual period and an additional 18 months of follow-up. OS and PFS were estimated using the Kaplan-Meier method. Results: In phase 1, 24 patients were enrolled. The MTD established was 5 mg/kg, given intravenously 5 days a week for the first 10 RT fractions, then 3 times a week for the duration of RT. The 7 patients enrolled in the third dose level and the 94 enrolled in phase 2 received this dose. Of these 101 patients, 87 were eligible and evaluable. Median survival time was 15.6 months (95% confidence interval [CI]: 12.9-17.6 months), not significantly different from that of the historical control (P=.36). Median PFS was 7.6 months (95% CI: 5.7-9.6 months). One patient (1%) experienced a grade 5 adverse event possibly related to therapy during the concurrent phase, and none experience toxicity during adjuvant TMZ therapy. Conclusions: Treatment was well tolerated, but median OS did not reach improvement specified by protocol compared to historical control, indicating that the combination of standard RT with TMZ and MGd did not achieve a significant survival advantage.

  2. Phase I/randomized phase II study of afatinib, an irreversible ErbB family blocker, with or without protracted temozolomide in adults with recurrent glioblastoma

    PubMed Central

    Reardon, David A.; Nabors, Louis B.; Mason, Warren P.; Perry, James R.; Shapiro, William; Kavan, Petr; Mathieu, David; Phuphanich, Surasak; Cseh, Agnieszka; Fu, Yali; Cong, Julie; Wind, Sven; Eisenstat, David D.

    2015-01-01

    Background This phase I/II trial evaluated the maximum tolerated dose (MTD) and pharmacokinetics of afatinib plus temozolomide as well as the efficacy and safety of afatinib as monotherapy (A) or with temozolomide (AT) vs temozolomide monotherapy (T) in patients with recurrent glioblastoma (GBM). Methods Phase I followed a traditional 3 + 3 dose-escalation design to determine MTD. Treatment cohorts were: afatinib 20, 40, and 50 mg/day (plus temozolomide 75 mg/m2/day for 21 days per 28-day cycle). In phase II, participants were randomized (stratified by age and KPS) to receive A, T or AT; A was dosed at 40 mg/day and T at 75 mg/m2 for 21 of 28 days. Primary endpoint was progression-free survival rate at 6 months (PFS-6). Participants were treated until intolerable adverse events (AEs) or disease progression. Results Recommended phase II dose was 40 mg/day (A) + T based on safety data from phase I (n = 32). Most frequent AEs in phase II (n = 119) were diarrhea (71% [A], 82% [AT]) and rash (71% [A] and 69% [AT]). Afatinib and temozolomide pharmacokinetics were unaffected by coadministration. Independently assessed PFS-6 rate was 3% (A), 10% (AT), and 23% (T). Median PFS was longer in afatinib-treated participants with epidermal growth factor receptor (EFGR) vIII-positive tumors versus EGFRvIII-negative tumors. Best overall response included partial response in 1 (A), 2 (AT), and 4 (T) participants and stable disease in 14 (A), 14 (AT), and 21 (T) participants. Conclusions Afatinib has a manageable safety profile but limited single-agent activity in unselected recurrent GBM patients. PMID:25140039

  3. Liposome encapsulated of temozolomide for the treatment of glioma tumor: preparation, characterization and evaluation.

    PubMed

    Gao, Jinhua; Wang, Zhonglan; Liu, Honghai; Wang, Longmei; Huang, Guihua

    2015-06-01

    Temozolomide plays a critical role in curing glioma at present. The purpose of this work was to develop a suitable drug delivery system which could prolong the half-life, improve the brain targeting, and reduce the systemic effect of the drug. Temozolomide-liposomes were formulated by the method of proliposomes. They were found to be relatively uniform in size of 156.70 ± 11.40 nm with a narrow polydispersity index (PI) of 0.29 ± 0.04. The average drug entrapment efficiency and loading capacity were 35.45 ± 1.48% and 2.81 ± 0.20%, respectively. The pH of temozolomide-liposomes was 6.46. In vitro release studies were conducted by a dynamic dialysis. The results showed that temozolomide released slowly from liposomes compared with the solution group. The release behavior of temozolomide-liposomes was in line with First-order kinetics and Weibull equation. The pharmacokinetics study was evaluated by pharmacokinetics parameters. The t(1/2β) and MRT of temozolomide-liposomes were 3.57 times and 1.27 times greater than that of temozolomide solution. The Cmax and AUC values of temozolomide-liposomes were 1.10 times and 1.55 times greater than that of temozolomide solution. The results of pharmacokinetics study showed temozolomide-liposomes prolonged the in vivo circulation time and increased AUC. Furthermore, the biodistribution in mice showed that temozolomide-liposomes preferentially decreased the accumulation of temozolomide in heart and lung and increased the drug concentration in brain after i.v. injection, which implied that temozolomide-liposomes improved the therapeutic effect in the brain and reduced the toxicity in lung and heart. PMID:26193943

  4. MiR-143 acts as a tumor suppressor by targeting N-RAS and enhances temozolomide-induced apoptosis in glioma.

    PubMed

    Wang, Lin; Shi, Zhu-Mei; Jiang, Cheng-Fei; Liu, Xue; Chen, Qiu-Dan; Qian, Xu; Li, Dong-Mei; Ge, Xin; Wang, Xie-Feng; Liu, Ling-Zhi; You, Yong-Ping; Liu, Ning; Jiang, Bing-Hua

    2014-07-30

    Therapeutic applications of microRNAs (miRNAs) in RAS-driven glioma were valuable, but their specific roles and functions have yet to be fully elucidated. Here, we firstly report that miR-143 directly targets the neuroblastoma RAS viral oncogene homolog (N-RAS) and functions as a tumor-suppressor in glioma. Overexpression of miR-143 decreased the expression of N-RAS, inhibited PI3K/AKT, MAPK/ERK signaling, and attenuated the accumulation of p65 in nucleus of glioma cells. In human clinical specimens, miR-143 was downregulated where an adverse with N-RAS expression was observed. Furthermore, overexpression of miR-143 decreased glioma cell migration, invasion, tube formation and slowed tumor growth and angiogenesis in a manner associated with N-RAS downregulation in vitro and in vivo. Finally, miR-143 also sensitizes glioma cells to temozolomide (TMZ),the first-line drug for glioma treatment. Taken together, for the first time, our results demonstrate that miR-143 plays a significant role in inactivating the RAS signaling pathway through the inhibition of N-RAS, which may provide a novel therapeutic strategy for treatment of glioma and other RAS-driven cancers.

  5. Dose-dense temozolomide regimen for the treatment of brain metastases from melanoma, breast cancer, or lung cancer not amenable to surgery or radiosurgery: a multicenter phase II study

    PubMed Central

    Siena, S.; Crinò, L.; Danova, M.; Del Prete, S.; Cascinu, S.; Salvagni, S.; Schiavetto, I.; Vitali, M.; Bajetta, E.

    2010-01-01

    Background: Brain metastases reduce survival because therapeutic options are limited. This phase II study evaluated the efficacy of single-agent therapy with alternating weekly, dose-dense temozolomide in pretreated patients with brain metastases prospectively stratified by primary tumor type. Methods: Eligible patients had bidimensionally measurable brain metastases from histologically/cytologically confirmed melanoma, breast cancer (BC), or non-small-cell lung cancer (NSCLC). Prior chemotherapy, radiotherapy, and whole-brain radiotherapy (WBRT) were allowed. Patients received temozolomide 150 mg/m2/day (days 1–7 and 15–21 every 28- or 35-day cycle). Results: In the intent-to-treat population (N = 157; 53 melanoma, 51 BC, and 53 NSCLC), one patient had complete response, nine (6%) had partial responses, and 31 (20%) had stable disease in the brain. Median progression-free survival was 56, 58, and 66 days for melanoma, BC, and NSCLC, respectively. Median overall survival was 100 days for melanoma, 172 days for NSCLC, and not evaluable in the BC group. Thrombocytopenia was the most common adverse event causing dose modification or treatment discontinuation. Grade 4 toxic effects were rare. Conclusions: This alternating weekly, dose-dense temozolomide regimen was well tolerated and clinically active in heavily pretreated patients with brain metastases, particularly in patients with melanoma. Combining temozolomide with WBRT or other agents may improve clinical outcomes. PMID:19767314

  6. Decitabine nanoconjugate sensitizes human glioblastoma cells to temozolomide.

    PubMed

    Cui, Yi; Naz, Asia; Thompson, David H; Irudayaraj, Joseph

    2015-04-01

    In this study, we developed and characterized a delivery system for the epigenetic demethylating drug, decitabine, to sensitize temozolomide-resistant human glioblastoma multiforme (GBM) cells to alkylating chemotherapy. A poly(lactic-co-glycolic acid) (PLGA) and poly(ethylene glycol) (PEG) based nanoconjugate was fabricated to encapsulate decitabine and achieved a better therapeutic response in GBM cells than that with the free drug. After synthesis, the highly efficient uptake process and intracellular dynamics of this nanoconjugate were monitored by single-molecule fluorescence tools. Our experiments demonstrated that, under an acidic pH due to active glycolysis in cancer cells, the PLGA-PEG nanovector could release the conjugated decitabine at a faster rate, after which the hydrolyzed lactic acid and glycolic acid would further acidify the intracellular microenvironment, thus providing positive feedback to increase the effective drug concentration and realize growth inhibition. In temozolomide-resistant GBM cells, decitabine can potentiate the cytotoxic DNA alkylation by counteracting cytosine methylation and reactivating tumor suppressor genes, such as p53 and p21. Owing to the excellent internalization and endolysosomal escape enabled by the PLGA-PEG backbone, the encapsulated decitabine exhibited a better anti-GBM potential than that of free drug molecules. Hence, the synthesized nanoconjugate and temozolomide could act in synergy to deliver a more potent and long-term antiproliferative effect against malignant GBM cells.

  7. Decitabine Nano-conjugate Sensitizing Human Glioblastoma Cells to Temozolomide

    PubMed Central

    Cui, Yi; Naz, Asia; Thompson, David H.; Irudayaraj, Joseph

    2015-01-01

    In this study we developed and characterized a delivery system for the epigenetic demethylating drug, decitabine, to sensitize temozolomide-resistant human glioblastoma multiforme (GBM) cells to alkylating chemotherapy. A poly(lactic-co-glycolic acid) (PLGA) and polyethylene glycol (PEG) based nano-conjugate was fabricated to encapsulate decitabine and achieved a better therapeutic response in GBM cells. After synthesis, the highly efficient uptake process and intracellular dynamics of this nano-conjugate was monitored by single-molecule fluorescence tools. Our experiments demonstrated that, under an acidic pH due to active glycolysis in cancer cells, the PLGA-PEG nano-vector could release the conjugated decitabine at a faster rate, after which the hydrolyzed lactic acid and glycolic acid would further acidify the intracellular microenvironment, thus providing a “positive feedback” to increase the effective drug concentration and realize growth inhibition. In temozolomide-resistant GBM cells, decitabine can potentiate the cytotoxic DNA alkylation by counteracting cytosine methylation and reactivating tumor suppressor genes, such as p53 and p21. Owing to excellent internalization and endo-lysosomal escape enabled by the PLGA-PEG backbone, the encapsulated decitabine exhibited a better anti-GBM potential than free drug molecules. Hence, the synthesized nano-conjugate and temozolomide could act in synergy to deliver a more potent and long-term anti-proliferation effect against malignant GBM cells. PMID:25751281

  8. Phase II and pharmacogenomics study of enzastaurin plus temozolomide during and following radiation therapy in patients with newly diagnosed glioblastoma multiforme and gliosarcoma

    PubMed Central

    Butowski, Nicholas; Chang, Susan M.; Lamborn, Kathleen R.; Polley, Mei–Yin; Pieper, Russell; Costello, Joseph F.; Vandenberg, Scott; Parvataneni, Rupa; Nicole, Angelina; Sneed, Patricia K.; Clarke, Jennifer; Hsieh, Emily; Costa, Bruno M.; Reis, Rui M.; Hristova-Kazmierski, Maria; Nicol, Steven J.; Thornton, Donald E.; Prados, Michael D.

    2011-01-01

    This open-label, single-arm, phase II study combined enzastaurin with temozolomide plus radiation therapy (RT) to treat glioblastoma multiforme (GBM) and gliosarcoma. Adults with newly diagnosed disease and Karnofsky performance status (KPS) ≥ 60 were enrolled. Treatment was started within 5 weeks after surgical diagnosis. RT consisted of 60 Gy over 6 weeks. Temozolomide was given at 75 mg/m2 daily during RT and then adjuvantly at 200 mg/m2 daily for 5 days, followed by a 23-day break. Enzastaurin was given once daily during RT and in the adjuvant period at 250 mg/day. Cycles were 28 days. The primary end point was overall survival (OS). Progression-free survival (PFS), toxicity, and correlations between efficacy and molecular markers analyzed from tumor tissue samples were also evaluated. A prospectively planned analysis compared OS and PFS of the current trial with outcomes from 3 historical phase II trials that combined novel agents with temozolomide plus RT in patients with GBM or gliosarcoma. Sixty-six patients were enrolled. The treatment regimen was well tolerated. OS (median, 74 weeks) and PFS (median, 36 weeks) results from the current trial were comparable to those from a prior phase II study using erlotininb and were significantly better than those from 2 other previous studies that used thalidomide or cis-retinoic acid, all in combination with temozolomide plus RT. A positive correlation between O-6-methylguanine-DNA methyltransferase promoter methylation and OS was observed. Adjusting for age and KPS, no other biomarker was associated with survival outcome. Correlation of relevant biomarkers with OS may be useful in future trials. PMID:21896554

  9. Phase II and pharmacogenomics study of enzastaurin plus temozolomide during and following radiation therapy in patients with newly diagnosed glioblastoma multiforme and gliosarcoma.

    PubMed

    Butowski, Nicholas; Chang, Susan M; Lamborn, Kathleen R; Polley, Mei-Yin; Pieper, Russell; Costello, Joseph F; Vandenberg, Scott; Parvataneni, Rupa; Nicole, Angelina; Sneed, Patricia K; Clarke, Jennifer; Hsieh, Emily; Costa, Bruno M; Reis, Rui M; Hristova-Kazmierski, Maria; Nicol, Steven J; Thornton, Donald E; Prados, Michael D

    2011-12-01

    This open-label, single-arm, phase II study combined enzastaurin with temozolomide plus radiation therapy (RT) to treat glioblastoma multiforme (GBM) and gliosarcoma. Adults with newly diagnosed disease and Karnofsky performance status (KPS) ≥ 60 were enrolled. Treatment was started within 5 weeks after surgical diagnosis. RT consisted of 60 Gy over 6 weeks. Temozolomide was given at 75 mg/m(2) daily during RT and then adjuvantly at 200 mg/m(2) daily for 5 days, followed by a 23-day break. Enzastaurin was given once daily during RT and in the adjuvant period at 250 mg/day. Cycles were 28 days. The primary end point was overall survival (OS). Progression-free survival (PFS), toxicity, and correlations between efficacy and molecular markers analyzed from tumor tissue samples were also evaluated. A prospectively planned analysis compared OS and PFS of the current trial with outcomes from 3 historical phase II trials that combined novel agents with temozolomide plus RT in patients with GBM or gliosarcoma. Sixty-six patients were enrolled. The treatment regimen was well tolerated. OS (median, 74 weeks) and PFS (median, 36 weeks) results from the current trial were comparable to those from a prior phase II study using erlotinib and were significantly better than those from 2 other previous studies that used thalidomide or cis-retinoic acid, all in combination with temozolomide plus RT. A positive correlation between O-6-methylguanine-DNA methyltransferase promoter methylation and OS was observed. Adjusting for age and KPS, no other biomarker was associated with survival outcome. Correlation of relevant biomarkers with OS may be useful in future trials.

  10. Amphiphilic chitosan-grafted-functionalized polylactic acid based nanoparticles as a delivery system for doxorubicin and temozolomide co-therapy.

    PubMed

    Di Martino, Antonio; Sedlarik, Vladimir

    2014-10-20

    The aim of this work was to investigate the potential of an amphiphilic system comprising chitosan-grafted polylactide and carboxyl-functionalized polylactide acid as a carrier for the controlled release and co-release of two DNA alkylating drugs: doxorubicin and temozolomide. Polylactide and carboxyl-functionalized polylactide acid were obtained through direct melt polycondensation reaction, using methanesulfonic acid as a non-toxic initiator, and subsequently these were grafted to the chitosan backbone through a coupling reaction, utilizing 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide as a condensing agent. ATR-FTIR analysis and conductometric titration confirmed that a reaction between CS and PLA, PLACA2% and PLACA5% occurred. Chitosan-grafted-polylactide and polylactide-citric acid nanoparticles were prepared via the polyelectrolyte complex technique, applying dextran sulphate as a polyanion, and loaded with doxorubicin and temozolomide. The diameter of particles, ζ-potential and their relationship to temperature and pH were analysed in all formulations. Encapsulation, co-encapsulation efficiency and release studies were conducted in different physiological simulated environments and human serum. Results showed the continuous release of drugs without an initial burst in different physiological media.

  11. Amphiphilic chitosan-grafted-functionalized polylactic acid based nanoparticles as a delivery system for doxorubicin and temozolomide co-therapy.

    PubMed

    Di Martino, Antonio; Sedlarik, Vladimir

    2014-10-20

    The aim of this work was to investigate the potential of an amphiphilic system comprising chitosan-grafted polylactide and carboxyl-functionalized polylactide acid as a carrier for the controlled release and co-release of two DNA alkylating drugs: doxorubicin and temozolomide. Polylactide and carboxyl-functionalized polylactide acid were obtained through direct melt polycondensation reaction, using methanesulfonic acid as a non-toxic initiator, and subsequently these were grafted to the chitosan backbone through a coupling reaction, utilizing 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide as a condensing agent. ATR-FTIR analysis and conductometric titration confirmed that a reaction between CS and PLA, PLACA2% and PLACA5% occurred. Chitosan-grafted-polylactide and polylactide-citric acid nanoparticles were prepared via the polyelectrolyte complex technique, applying dextran sulphate as a polyanion, and loaded with doxorubicin and temozolomide. The diameter of particles, ζ-potential and their relationship to temperature and pH were analysed in all formulations. Encapsulation, co-encapsulation efficiency and release studies were conducted in different physiological simulated environments and human serum. Results showed the continuous release of drugs without an initial burst in different physiological media. PMID:25124059

  12. Temozolomide/PLGA microparticles plus vatalanib inhibits tumor growth and angiogenesis in an orthotopic glioma model.

    PubMed

    Zhang, Yu-Hui; Yue, Zhi-Jian; Zhang, He; Tang, Gu-Sheng; Wang, Yang; Liu, Jian-Min

    2010-11-01

    Temozolomide (TM) has anti-tumor activity in patients with malignant glioma. Implantable poly (D,L-lactide-co-glycolide) (PLGA) microparticles of TM (TM-MS) have been developed, enhancing the cytotoxicity of TM to Glioma C6 cells. Vatalanib, as anti-angiogenic agent, has also shown anti-tumor activity with malignant gliomas. We examined the combined effects of TM-MS and vatalanib in a rat orthotopic glioma model and found TM-MS offered a greater tumor inhibition than TM, and combination treatment with both of them improved the survival time versus single agent therapy. The combination treatment also demonstrated an inhibition to rat glioma tumors, a significant decrease in cell proliferation, an increase in apoptosis, and a lower microvessel density within the glioma tumors. The results suggest that TM-MS can more effectively inhibit tumor than TM, and combination treatment with TM-MS and vatalanib inhibits tumor growth and angiogenesis and may prove to be a promising therapy for malignant gliomas. PMID:20816959

  13. The role of trimetazidine in cardiovascular disease: beyond an anti-anginal agent.

    PubMed

    McCarthy, Cian P; Mullins, Kieran V; Kerins, David M

    2016-10-01

    With evidence for efficacy in such diverse clinical settings such as stable coronary artery disease, reperfusion injury, and contrast-induced nephropathy, trimetazidine (TMZ) is novel among cardiovascular agents. In spite of this and almost half a century of clinical experience with the drug, it remains licensed only as an adjunct in the management of angina pectoris in patients who are inadequately controlled by or intolerant to first-line therapies. Although no single pharmacological mechanism has been hitherto universally accepted, TMZ is known to target deranged cellular energetics particularly in ischaemic myocardial tissue. Mechanistically, this separates the drug from conventional anti-anginal therapies, namely beta-adrenergic antagonists, calcium channel blockers, and nitrates. Moreover, a haemodynamically neutral side-effect profile should make TMZ a much more attractive therapeutic agent in this setting. Such ostensibly beneficial pharmacodynamics notwithstanding, the drug has a limited role in angina pectoris treatment algorithms. Concerns regarding a potential for new onset movement disorder further complicate its use and have led to a licensing revocation in some jurisdictions for the treatment of vestibular disorders. In this review article, we examine the pertinent literature and assess the evidence base for TMZ as a viable treatment option in a number of clinical settings. PMID:27533944

  14. Resveratrol sensitizes glioblastoma-initiating cells to temozolomide by inducing cell apoptosis and promoting differentiation.

    PubMed

    Li, Hao; Liu, Yaodong; Jiao, Yumin; Guo, Anchen; Xu, Xiaoxue; Qu, Xianjun; Wang, Shuo; Zhao, Jizong; Li, Ye; Cao, Yong

    2016-01-01

    Glioblastoma-initiating cells play crucial roles in the origin, growth, and recurrence of glioblastoma multiforme. The elimination of glioblastoma-initiating cells is believed to be a key strategy for achieving long-term survival of glioblastoma patients due to the highly resistant property of glioblastoma-initiating cells to temozolomide. Resveratrol, a naturally occurring polyphenol, has been widely studied as a promising candidate for cancer prevention and treatment. Whether resveratrol could enhance the sensitivity of glioblastoma-initiating cells to temozolomide therapy has not yet been reported. Here, using patient-derived glioblastoma-initiating cell lines, we found that resveratrol sensitized glioblastoma-initiating cells to temozolomide both in vitro and in vivo. Furthermore, we showed that resveratrol enhanced glioblastoma-initiating cells to temozolomide-induced apoptosis through DNA double-stranded breaks/pATM/pATR/p53 pathway activation, and promoted glioblastoma-initiating cell differentiation involving p-STAT3 inactivation. Our results propose that temozolomide and resveratrol combination strategy may be effective in the management of glioblastoma patients, particularly for those patients who have been present with a high abundance of glioblastoma-initiating cells in their tumors and show slight responsiveness to temozolomide.

  15. Phase II Trial of Bevacizumab in Combination With Temozolomide as First-Line Treatment in Patients With Metastatic Uveal Melanoma

    PubMed Central

    Diallo, Alhassane; Etienne-Grimaldi, Marie-Christine; Bidard, François-Clément; Rodrigues, Manuel; Plancher, Corine; Mariani, Pascale; Cassoux, Nathalie; Decaudin, Didier; Asselain, Bernard; Servois, Vincent

    2016-01-01

    Lessons Learned Trials dedicated to metastatic uveal melanoma are needed because of the poor prognosis of this rare cancer and because its biology is distinct from that of cutaneous melanoma. Agents targeting the MEK/ERK/MAP kinase pathways are being tested. Background. In experimental models, bevacizumab suppressed in vitro growth and in vivo hepatic metastasis of ocular melanoma cells. Additional preclinical data suggested a potential benefit when combining bevacizumab with dacarbazine. Methods. This noncomparative phase II study evaluated a combination of bevacizumab (10 mg/kg on days 8 and 22) with temozolomide (150 mg/m2 on days 1–7 and 15–21) in 36 patients with metastatic uveal melanoma (MUM). The primary endpoint was the progression-free rate (PFR) at 6 months. Using a modified 2-step Fleming plan, at least 10 of 35 patients were required to support a predefined PFR at 6 months of 40%. Secondary objectives were progression-free survival (PFS), overall survival (OS), and safety; liver perfusion computed tomography (CT) for response imaging; and impact of VEGF-A gene polymorphisms on bevacizumab pharmacodynamics. Results. First- and second-step analyses revealed nonprogression at 6 months in 3 of 17 and 8 of 35 patients, respectively. Finally, the 6-month PFR was 23% (95% confidence interval [CI]: 10–39), with long-lasting stable disease in 5 patients (14%). Median PFS and OS were 12 weeks and 10 months, respectively. No unexpected toxicity occurred. Liver perfusion CT imaging was not useful in assessing tumor response, and VEGF-A gene polymorphisms were not correlated with toxicity or survival. Conclusion. In patients with MUM, a combination of bevacizumab plus temozolomide achieved a 6-month PFR of 23%. PMID:26911405

  16. Enzastaurin plus temozolomide with radiation therapy in glioblastoma multiforme: A phase I study†

    PubMed Central

    Butowski, Nicholas; Chang, Susan M.; Lamborn, Kathleen R.; Polley, Mei Yin; Parvataneni, R.; Hristova-Kazmierski, Maria; Musib, Luna; Nicol, Steven J.; Thornton, Donald E.; Prados, Michael D.

    2010-01-01

    We conducted a phase I study to determine the safety and recommended phase II dose of enzastaurin (oral inhibitor of the protein kinase C-beta [PKCβ] and the PI3K/AKT pathways) when given in combination with radiation therapy (RT) plus temozolomide to patients with newly diagnosed glioblastoma multiforme or gliosarcoma. Patients with Karnofsky performance status ≥60 and no enzyme-inducing anti-epileptic drugs received RT (60 Gy) over 6 weeks, concurrently with temozolomide (75 mg/m2 daily) followed by adjuvant temozolomide (200 mg/m2) for 5 days/28-d cycle. Enzastaurin was given once daily during RT and adjuvantly with temozolomide; the starting dose of 250 mg/d was escalated to 500 mg/d if ≤1/6 patients had dose-limiting toxicity (DLT) during RT and the first adjuvant cycle. Patients continued treatment for 12 adjuvant cycles unless disease progression or unacceptable toxicity occurred. Twelve patients enrolled. There was no DLT in the first 6 patients treated with 250 mg enzastaurin. At 500 mg, 2 of 6 patients experienced a DLT (1 Grade 4 and 1 Grade 3 thrombocytopenia). The patient with Grade 3 DLT recovered to Grade <1 within 28 days and adjuvant temozolomide and enzastaurin was reinitiated with dose reductions. The other patient recovered to Grade <1 toxicity after 28 days and did not restart treatment. Enzastaurin 250 mg/d given concomitantly with RT and temozolomide and adjuvantly with temozolomide was well tolerated and is the recommended phase II dose. The proceeding phase II trial has finished accrual and results will be reported in 2009. PMID:20156802

  17. MGMT expression predicts response to temozolomide in pancreatic neuroendocrine tumors.

    PubMed

    Cros, J; Hentic, O; Rebours, V; Zappa, M; Gille, N; Theou-Anton, N; Vernerey, D; Maire, F; Lévy, P; Bedossa, P; Paradis, V; Hammel, P; Ruszniewski, P; Couvelard, A

    2016-08-01

    Temozolomide (TEM) showed encouraging results in well-differentiated pancreatic neuroendocrine tumors (WDPNETs). Low O(6)-methylguanine-DNA methyltransferase (MGMT) expression and MGMT promoter methylation within tumors correlate with a better outcome under TEM-based chemotherapy in glioblastoma. We aimed to assess whether MGMT expression and MGMT promoter methylation could help predict the efficacy of TEM-based chemotherapy in patients with WDPNET. Consecutive patients with progressive WDPNET and/or liver involvement over 50% who received TEM between 2006 and 2012 were retrospectively studied. Tumor response was assessed according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 guidelines. Nuclear expression of MGMT was assessed by immunochemistry (H-score, 0-300) and MGMT promoter methylation by pyrosequencing. Forty-three patients (21 men, 58years (27-84)) with grade 1 WDPNET (n=6) or 2 (n=36) were analyzed. Objective response, stable disease, and progression rates were seen in 17 patients (39.5%), 18 patients (41.9%), and 8 patients (18.6%), respectively. Low MGMT expression (≤50) was associated with radiological objective response (P=0.04) and better progression-free survival (PFS) (HR=0.35 (0.15-0.81), P=0.01). Disease control rate at 18months of treatment remained satisfying with an MGMT score up to 100 (74%) but dropped with a higher expression. High MGMT promoter methylation was associated with a low MGMT expression and longer PFS (HR=0.37 (0.29-1.08), P=0.05). Low MGMT score (≤50) appears to predict an objective tumor response, whereas an intermediate MGMT score (50-100) seems to be associated with prolonged stable disease. PMID:27353036

  18. MGMT expression predicts response to temozolomide in pancreatic neuroendocrine tumors.

    PubMed

    Cros, J; Hentic, O; Rebours, V; Zappa, M; Gille, N; Theou-Anton, N; Vernerey, D; Maire, F; Lévy, P; Bedossa, P; Paradis, V; Hammel, P; Ruszniewski, P; Couvelard, A

    2016-08-01

    Temozolomide (TEM) showed encouraging results in well-differentiated pancreatic neuroendocrine tumors (WDPNETs). Low O(6)-methylguanine-DNA methyltransferase (MGMT) expression and MGMT promoter methylation within tumors correlate with a better outcome under TEM-based chemotherapy in glioblastoma. We aimed to assess whether MGMT expression and MGMT promoter methylation could help predict the efficacy of TEM-based chemotherapy in patients with WDPNET. Consecutive patients with progressive WDPNET and/or liver involvement over 50% who received TEM between 2006 and 2012 were retrospectively studied. Tumor response was assessed according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 guidelines. Nuclear expression of MGMT was assessed by immunochemistry (H-score, 0-300) and MGMT promoter methylation by pyrosequencing. Forty-three patients (21 men, 58years (27-84)) with grade 1 WDPNET (n=6) or 2 (n=36) were analyzed. Objective response, stable disease, and progression rates were seen in 17 patients (39.5%), 18 patients (41.9%), and 8 patients (18.6%), respectively. Low MGMT expression (≤50) was associated with radiological objective response (P=0.04) and better progression-free survival (PFS) (HR=0.35 (0.15-0.81), P=0.01). Disease control rate at 18months of treatment remained satisfying with an MGMT score up to 100 (74%) but dropped with a higher expression. High MGMT promoter methylation was associated with a low MGMT expression and longer PFS (HR=0.37 (0.29-1.08), P=0.05). Low MGMT score (≤50) appears to predict an objective tumor response, whereas an intermediate MGMT score (50-100) seems to be associated with prolonged stable disease.

  19. New dry powders for inhalation containing temozolomide-based nanomicelles for improved lung cancer therapy.

    PubMed

    Rosière, Rémi; Gelbcke, Michel; Mathieu, Véronique; Van Antwerpen, Pierre; Amighi, Karim; Wauthoz, Nathalie

    2015-09-01

    Besides the numerous advantages of a chemotherapy administered by the inhalation route for lung cancer therapy, dry powder for inhalation (DPI) offers many advantages compared to other techniques and seems to be a technique that is well-adapted to an anticancer treatment. DPI formulations were developed using the cytotoxic drug temozolomide and a new folate-grafted self-assembling copolymer, a conjugate of three components, folate-polyethylene glycol-hydrophobically-modified dextran (F-PEG-HMD). F-PEG-HMD was synthesized using carbodiimide-mediated coupling chemistry in three main steps. F-PEG-HMD was characterized by 1H-NMR, mass spectrometry and thermal analysis. F-PEG-HMD presented a critical micellar concentration in water of 4x10-7 M. F-PEG-HMD nanomicelles were characterized by a trimodal particle size distribution with Z-average diameter of 83±1 nm in water. Temozolomide-loaded nanomicelles were prepared by solubilization of F-PEG-HMD in the presence of temozolomide. Temozolomide solubility in water was increased in the presence of F-PEG-HMD (2-fold increase in molar solubility) which could potentially lead to increased local concentrations in the tumor site. The temozolomide-loaded F-PEG-HMD nanomicelles were characterized by a Z-average diameter of ~50 to ~60 nm, depending on the F-PEG-HMD concentration used. The nanomicelles were then spray-dried to produce dry powders. Temozolomide remained stable during all the formulation steps, confirmed by similar in vitro anticancer properties for the DPI formulations and a raw temozolomide solution. Two of the developed DPI formulations were characterized by good aerodynamic properties (with a fine particle fraction of up to 50%) and were able to release the F-PEG-HMD nanomicelles quickly in aqueous media. Moreover, in vitro, the two DPI formulations showed wide pulmonary deposition in the lower respiratory tract where adenocarcinomas are more often found. The present study, therefore, shows that F

  20. New dry powders for inhalation containing temozolomide-based nanomicelles for improved lung cancer therapy.

    PubMed

    Rosière, Rémi; Gelbcke, Michel; Mathieu, Véronique; Van Antwerpen, Pierre; Amighi, Karim; Wauthoz, Nathalie

    2015-09-01

    Besides the numerous advantages of a chemotherapy administered by the inhalation route for lung cancer therapy, dry powder for inhalation (DPI) offers many advantages compared to other techniques and seems to be a technique that is well-adapted to an anticancer treatment. DPI formulations were developed using the cytotoxic drug temozolomide and a new folate-grafted self-assembling copolymer, a conjugate of three components, folate-polyethylene glycol-hydrophobically-modified dextran (F-PEG-HMD). F-PEG-HMD was synthesized using carbodiimide-mediated coupling chemistry in three main steps. F-PEG-HMD was characterized by 1H-NMR, mass spectrometry and thermal analysis. F-PEG-HMD presented a critical micellar concentration in water of 4x10-7 M. F-PEG-HMD nanomicelles were characterized by a trimodal particle size distribution with Z-average diameter of 83±1 nm in water. Temozolomide-loaded nanomicelles were prepared by solubilization of F-PEG-HMD in the presence of temozolomide. Temozolomide solubility in water was increased in the presence of F-PEG-HMD (2-fold increase in molar solubility) which could potentially lead to increased local concentrations in the tumor site. The temozolomide-loaded F-PEG-HMD nanomicelles were characterized by a Z-average diameter of ~50 to ~60 nm, depending on the F-PEG-HMD concentration used. The nanomicelles were then spray-dried to produce dry powders. Temozolomide remained stable during all the formulation steps, confirmed by similar in vitro anticancer properties for the DPI formulations and a raw temozolomide solution. Two of the developed DPI formulations were characterized by good aerodynamic properties (with a fine particle fraction of up to 50%) and were able to release the F-PEG-HMD nanomicelles quickly in aqueous media. Moreover, in vitro, the two DPI formulations showed wide pulmonary deposition in the lower respiratory tract where adenocarcinomas are more often found. The present study, therefore, shows that F

  1. Inhibition of STAT3 reverses alkylator resistance through modulation of the AKT and β-catenin signaling pathways.

    PubMed

    Wang, Yongzhi; Chen, Lingchao; Bao, Zhaoshi; Li, Shouwei; You, Gan; Yan, Wei; Shi, Zhendong; Liu, Yanwei; Yang, Pei; Zhang, Wei; Han, Lei; Kang, Chunsheng; Jiang, Tao

    2011-11-01

    Activation of signal transducer and activator of transcription 3 (STAT3) is associated with poor clinical outcome of glioblastoma (GBM). However, the role of STAT3 in resistance to alkylator-based chemotherapy remains unknown. Here, we retrospectively analyzed the phosphorylated STAT3 (p-STAT3) profile of 68 GBM patients receiving alkylator therapy, identifying p-STAT3 as an independent unfavorable prognostic factor for progression-free and overall survival. Additionally, elevated p-STAT3 expression correlated with resistance to alkylator therapy. In vitro analysis revealed that U251 and U87 human glioma cells were refractory to treatment with the common alkylating agent temozolomide (TMZ), with only a modest impact on AKT and β-catenin activation in the context of high p-STAT3. Inhibition of STAT3 in these cells significantly enhanced the effect of TMZ. Inhibition of STAT3 dramatically decreased the IC50 of TMZ, increasing TMZ-induced apoptosis while up-regulating expression of Bcl-2 and down-regulating expression of Bax. Furthermore, inhibition of STAT3 increased TMZ-induced G₀-G₁ arrest and decreased Cyclin D1 expression compared to TMZ alone. Together, these results indicate that inhibition of STAT3 sensitizes glioma cells to TMZ, at least in part, by blocking the p-AKT and β-catenin pathways. These findings strongly support the hypothesis that STAT3 inhibition significantly improves the clinical efficacy of alkylating agents.

  2. Enhanced accumulation of curcumin and temozolomide loaded magnetic nanoparticles executes profound cytotoxic effect in glioblastoma spheroid model.

    PubMed

    Dilnawaz, Fahima; Sahoo, Sanjeeb Kumar

    2013-11-01

    Glioblastomas (GBMs) are highly lethal primary brain tumours. Treatment of these malignant gliomas remains ineffective as these are extremely resistant to chemotherapeutic applications. Furthermore, combination therapy for cancer treatment is becoming more popular because it generates synergistic anticancer effects, by reducing individual drug-related toxicity and associated side effects. Currently, magnetic nanoparticles (MNPs) based drug delivery system has attracted much more attention owing to its intrinsic magnetic properties and drug loading capacity. In the present study, MNPs based drug delivery approach for co-delivering of potent chemotherapeutic drugs such as Curcumin (herbal drug) and Temozolomide (DNA methylating agent) has been implemented. The dual drug loaded MNPs formulations were evaluated in two-dimensional (2-D) monolayer culture and three-dimensional (3-D) tumour spheroid culture of T-98G cells for understanding the therapeutic discrepancy. The dual drug loaded MNPs formulations demonstrated higher cytotoxic effect than single drug loaded MNPs formulations as compared to their corresponding native drugs in 2-D and 3-D culture. The combination index (CI) analysis revealed synergistic mode of action of dual drug loaded MNPs formulations, which was further confirmed by cell death induction assay mediated by acridine orange (AO)/propidium iodide (PI) staining, illustrating higher efficacy of the formulation towards GBM therapy.

  3. Restoration of sensitivity in chemo-resistant glioma cells by cold atmospheric plasma.

    PubMed

    Köritzer, Julia; Boxhammer, Veronika; Schäfer, Andrea; Shimizu, Tetsuji; Klämpfl, Tobias G; Li, Yang-Fang; Welz, Christian; Schwenk-Zieger, Sabina; Morfill, Gregor E; Zimmermann, Julia L; Schlegel, Jürgen

    2013-01-01

    Glioblastoma (GBM) is the most common and aggressive brain tumor in adults. Despite multimodal treatments including surgery, chemotherapy and radiotherapy the prognosis remains poor and relapse occurs regularly. The alkylating agent temozolomide (TMZ) has been shown to improve the overall survival in patients with malignant gliomas, especially in tumors with methylated promoter of the O6-methylguanine-DNA-methyltransferase (MGMT) gene. However, intrinsic and acquired resistance towards TMZ makes it crucial to find new therapeutic strategies aimed at improving the prognosis of patients suffering from malignant gliomas. Cold atmospheric plasma is a new auspicious candidate in cancer treatment. In the present study we demonstrate the anti-cancer properties of different dosages of cold atmospheric plasma (CAP) both in TMZ-sensitive and TMZ-resistant cells by proliferation assay, immunoblotting, cell cycle analysis, and clonogenicity assay. Importantly, CAP treatment restored the responsiveness of resistant glioma cells towards TMZ therapy. Concomitant treatment with CAP and TMZ led to inhibition of cell growth and cell cycle arrest, thus CAP might be a promising candidate for combination therapy especially for patients suffering from GBMs showing an unfavorable MGMT status and TMZ resistance.

  4. Histone/protein deacetylase SIRT1 is an anticancer therapeutic target

    PubMed Central

    Hwang, Bor-Jang; Madabushi, Amrita; Jin, Jin; Lin, Shiou-Yuh S; Lu, A-Lien

    2014-01-01

    SIRT1, a member of the NAD+-dependent histone/protein deacetylase family, is involved in chromatin remodeling, DNA repair, and stress response and is a potential drug target. 5-fluorouracil (FU) and the SN1-type DNA methylating agent temozolomide (TMZ) are anticancer agents. In this study, we demonstrate that sirt1 knockout mouse embryonic fibroblast cells are more sensitive to FU and DNA methylating agents than normal cells. Based on these findings, the chemotherapy efficacy of SIRT1 inhibitors in combination with FU or TMZ were tested with human breast cancer cells. We found that treatments combining SIRT1 inhibitors with FU or TMZ show synergistic reduction of cell viability and colony formation of breast cancer cells. Thus, inhibition of SIRT1 activity provides a novel anticancer strategy. PMID:24959376

  5. Vorinostat Enhances Cytotoxicity of SN-38 and Temozolomide in Ewing Sarcoma Cells and Activates STAT3/AKT/MAPK Pathways

    PubMed Central

    Sampson, Valerie B.; Vetter, Nancy S.; Kamara, Davida F.; Collier, Anderson B.; Gresh, Renee C.; Kolb, E. Anders

    2015-01-01

    Histone deacetylase inhibitors (HDACi) have been evaluated in patients with Ewing sarcoma (EWS) but demonstrated limited activity. To better understand the potential for HDACi in EWS, we evaluated the combination of the HDACi vorinostat, with DNA damaging agents SN-38 (the active metabolite of irinotecan and topoisomerase 1 inhibitor) plus the alkylating agent temozolomide (ST). Drugs were evaluated in sequential and simultaneous combinations in two EWS cell lines. Results demonstrate that cell viability, DNA damage and reactive oxygen species (ROS) production are dependent on the sequence of drug administration. Enhanced cytotoxicity is exhibited in vitro in EWS cell lines treated with ST administered before vorinostat, which was modestly higher than concomitant treatment and superior to vorinostat administered before ST. Drug combinations downregulate cyclin D1 to induce G0/G1 arrest and promote apoptosis by cleavage of caspase-3 and PARP. When ST is administered before or concomitantly with vorinostat there is activation of STAT3, MAPK and the p53 pathway. In contrast, when vorinostat is administered before ST, there is DNA repair, increased AKT phosphorylation and reduced H2B acetylation. Inhibition of AKT using the small molecule inhibitor MK-2206 did not restore H2B acetylation. Combining ST with the dual ALK and IGF-1R inhibitor, AZD3463 simultaneously inhibited STAT3 and AKT to enhance the cytotoxic effects of ST and further reduce cell growth suggesting that STAT3 and AKT activation were in part mediated by ALK and IGF-1R signaling. In summary, potent antiproliferative and proapoptotic activity were demonstrated for ST induced DNA damage before or simultaneous with HDAC inhibition and cell death was mediated through the p53 pathway. These observations may aid in designing new protocols for treating pediatric patients with high-risk EWS. PMID:26571493

  6. Nimotuzumab enhances temozolomide-induced growth suppression of glioma cells expressing mutant EGFR in vivo.

    PubMed

    Nitta, Yusuke; Shimizu, Saki; Shishido-Hara, Yukiko; Suzuki, Kaori; Shiokawa, Yoshiaki; Nagane, Motoo

    2016-03-01

    A mutant form of epidermal growth factor receptor (EGFR), EGFRvIII, is common in glioblastoma (GBM) and confers enhanced tumorigenic activity and drug resistance. Nimotuzumab, an anti-EGFR antibody, has shown preclinical and clinical activity to GBM, but its specific activity against EGFRvIII has not been fully investigated. Human glioma U87MG or LNZ308 cells overexpressing either wild-type (wt) EGFR or EGFRvIII were treated with nimotuzumab, temozolomide, or both. Expression and phosphorylation status of molecules were determined by Western blot analysis. Methylation status of promoter region of O(6) -methylguanine-DNA methyltransferase (MGMT) was detected by methylation-specific PCR. Antitumor activity was tested using nude mice bearing either subcutaneous or intracerebral xenografts along with analyses of EGFR phosphorylation status, proliferation, apoptosis, and vessel density. Nimotuzumab treatment resulted in reduction of EGFRvIII tyrosine phosphorylation with a decrease in Akt phosphorylation that was greater than that of wtEGFR. Correspondingly, antitumor effects, growth suppression and survival elongation, were more significant in mice bearing either subcutaneous or intracerebral tumor expressing EGFRvIII than in those expressing wtEGFR. These effects were markedly increased when temozolomide was combined with nimotuzumab. The post-treatment recurrent brain tumors exhibited a decrease in expression of the mismatch repair (MMR) proteins, MSH6 and MLH1, but their methylated MGMT status did not changed. Nimotuzumab has in vivo antitumor activity against GBM, especially those expressing EGFRvIII, when combined with temozolomide. This could provide a basis for preselection of patients with GBM by EGFR status who might benefit from the nimotuzumab and temozolomide combination therapy. PMID:26778701

  7. A transcriptomic signature mediated by HOXA9 promotes human glioblastoma initiation, aggressiveness and resistance to temozolomide

    PubMed Central

    Pojo, Marta; Gonçalves, Céline S.; Xavier-Magalhães, Ana; Oliveira, Ana Isabel; Gonçalves, Tiago; Correia, Sara; Rodrigues, Ana J.; Costa, Sandra; Pinto, Luísa; Pinto, Afonso A.; Lopes, José M.; Reis, Rui M.; Rocha, Miguel; Sousa, Nuno; Costa, Bruno M.

    2015-01-01

    Glioblastoma is the most malignant brain tumor, exhibiting remarkable resistance to treatment. Here we investigated the oncogenic potential of HOXA9 in gliomagenesis, the molecular and cellular mechanisms by which HOXA9 renders glioblastoma more aggressive, and how HOXA9 affects response to chemotherapy and survival. The prognostic value of HOXA9 in glioblastoma patients was validated in two large datasets from TCGA and Rembrandt, where high HOXA9 levels were associated with shorter survival. Transcriptomic analyses identified novel HOXA9-target genes with key roles in cancer-related processes, including cell proliferation, DNA repair, and stem cell maintenance. Functional studies with HOXA9-overexpressing and HOXA9-silenced glioblastoma cell models revealed that HOXA9 promotes cell viability, stemness and invasion, and inhibits apoptosis. Additionally, HOXA9 promoted the malignant transformation of human immortalized astrocytes in an orthotopic in vivo model, and caused tumor-associated death. HOXA9 also mediated resistance to temozolomide treatment in vitro and in vivo via upregulation of BCL2. Importantly, the pharmacological inhibition of BCL2 with the BH3 mimetic ABT-737 reverted temozolomide resistance in HOXA9-positive cells. These data establish HOXA9 as a driver of glioma initiation, aggressiveness and resistance to therapy. In the future, the combination of BH3 mimetics with temozolomide should be further explored as an alternative treatment for glioblastoma. PMID:25762636

  8. Afatinib, an irreversible ErbB family blocker, with protracted temozolomide in recurrent glioblastoma: A case report

    PubMed Central

    Alshami, Jad; Guiot, Marie-Christine; Owen, Scott; Kavan, Petr; Gibson, Neil; Solca, Flavio; Cseh, Agnieszka; Reardon, David A.; Muanza, Thierry

    2015-01-01

    There are few effective treatments for recurrent glioblastoma multiforme (GBM). We present a patient with recurrent GBM who achieved a prolonged response to treatment with afatinib, an irreversible ErbB family blocker, plus temozolomide. A 58-year-old female patient was diagnosed with multifocal primary GBM. After surgical resection, first-line therapy comprised radiotherapy and temozolomide. Following disease progression after 3 temozolomide cycles, the patient entered a phase I/II clinical trial of afatinib (20–40 mg daily for 28 days) plus temozolomide (50 mg/m2 every 21/28 days). Next-generation sequencing analysis of the brain tumor specimen was performed. At the last assessment, 63 treatment cycles had been completed and the patient had survived for ~5 years since recurrence. Significant disease regression was observed after 5 cycles and was maintained during long-term follow-up. Adverse events were consistent with the known tolerability profile of afatinib and were managed by treatment interruption/dose reduction. The patient had several epidermal growth factor receptor (EGFR) aberrations, including gene amplification and EGFRvIII positivity. Three somatic mutations were identified, including an unprecedented extracellular-domain substitution (D247Y). The patient has survived ~6-fold longer than normally expected in patients with recurrent GBM. The complex EGFR genotype may underlie sustained response to afatinib plus temozolomide. PMID:26423602

  9. The DNA damage/repair cascade in glioblastoma cell lines after chemotherapeutic agent treatment.

    PubMed

    Annovazzi, Laura; Caldera, Valentina; Mellai, Marta; Riganti, Chiara; Battaglia, Luigi; Chirio, Daniela; Melcarne, Antonio; Schiffer, Davide

    2015-01-01

    Therapeutic resistance in glioblastoma multiforme (GBM) has been linked to a subpopulation of cells with stem cell-like properties, the glioma stem cells (GSCs), responsible for cancer progression and recurrence. This study investigated the in vitro cytotoxicity of three chemotherapeutics, temozolomide (TMZ), doxorubicin (Dox) and paclitaxel (PTX) on glioma cell lines, by analyzing the molecular mechanisms leading to DNA repair and cell resistance, or to cell death. The drugs were tested on 16 GBM cell lines, grown as neurospheres (NS) or adherent cells (AC), by studying DNA damage occurrence by Comet assay, the expression by immunofluorescence and western blotting of checkpoint/repair molecules and apoptosis. The three drugs were able to provoke a genotoxic injury and to inhibit dose- and time-dependently cell proliferation, more evidently in AC than in NS. The first cell response to DNA damage was the activation of the damage sensors (p-ATM, p-53BP1, γ-H2AX), followed by repair effectors; the expression of checkpoint/repair molecules appeared higher in NS than in AC. The non-homologous repair pathway (NHEJ) seemed more involved than the homologous one (HR). Apoptosis occurred after long treatment times, but only a small percentage of cells in NS underwent death, even at high drug concentration, whereas most cells survived in a quiescent state and resumed proliferation after drug removal. In tumor specimens, checkpoint/repair proteins were constitutively expressed in GBMs, but not in low-grade gliomas.

  10. Poly (ADP-ribose) polymerases inhibitor, Zj6413, as a potential therapeutic agent against breast cancer.

    PubMed

    Zhou, Qin; Ji, Ming; Zhou, Jie; Jin, Jing; Xue, Nina; Chen, Ju; Xu, Bailing; Chen, Xiaoguang

    2016-05-01

    Poly (ADP-ribose) polymerases (PARPs) facilitate repairing of cancer cell DNA damage as a mean to promote cancer proliferation and metastasis. Inhibitors of PARPs which interfering DNA repair, in context of defects in other DNA repair mechanisms, can thus be potentially exploited to inhibit or even kill cancer cells. However, nondiscriminatory inhibition of PARPs, such as PARP2, may lead to undesired consequences. Here, we demonstrated the design and development of the Zj6413 as a potent and selective PARP1 catalytic inhibitor. It trapped PARP1/2 at damaged sites of DNA. As expected, the Zj6413 showed notable anti-tumor activity against breast cancer gene (BRCA) deficient triple negative breast cancers (TNBCs). Zj6413 treated breast cancers (BCs) showed an elevated level of DNA damage evidenced by the accumulation of γ-H2AX foci and DNA damaged related proteins. Zj6413 also induced G2/M arrest and cell death in the MX-1, MDA-MB-453 BC cells, exerted chemo-sensitizing effect on BRCA proficient cancer cells and potentiated Temozolomide (TMZ)'s cytotoxicity in MX-1 xenograft tumors mice. In conclusion, our study provided evidence that a new PARP inhibitor strongly inhibited the catalytic activity of PARPs, trapped them on nicked DNA and damaged the cancer cells, eventually inhibiting the growth of breast tumor cells in vitro and in vivo. PMID:26920250

  11. Enhancement of Glioma Radiotherapy and Chemotherapy Response With Targeted Antibody Therapy Against Death Receptor 5

    SciTech Connect

    Fiveash, John B. Gillespie, G. Yancey; Oliver, Patsy G.; Zhou Tong; Belenky, Michael L.; Buchsbaum, Donald J.

    2008-06-01

    Purpose: TRA-8 is an agonistic mouse monoclonal antibody that binds to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) death receptor 5, which induces apoptosis in cancer cells through a caspase-8-dependent mechanism. We investigated the ability of TRA-8 to augment the radiotherapy (RT) and chemotherapy response of human glioma cells in vitro and in vivo. Methods and Materials: The in vitro cytotoxicity of TRA-8 and temozolomide (Tmz) or RT was examined using adenosine triphosphate-dependent viability and clonogenic survival assays with five glioma cell lines. Death receptor 5 expression was determined by flow cytometry. In vivo studies included subcutaneous and intracranial xenograft models testing various combination treatments, including RT, Tmz, and TRA-8. Results: TRA-8, combined with Tmz or RT, produced enhanced cytotoxicity against five glioma cell lines compared with the use of the individual agents alone. Death receptor 5 upregulation occurred in response to RT. Complete tumor regression in the subcutaneous experiments was the most common in animals that received combination therapy with TRA-8/Tmz/RT. TRA-8 enhanced tumor growth delay in combination with RT or Tmz. TRA-8 alone had limited activity against intracranial tumors. In contrast, the median survival of mice treated with TRA-8/Tmz/RT was significantly greater than the control or TRA-8-alone-treated mice. The median survival of the mice treated with TRA-8/Tmz/RT or chemoradiotherapy only was significantly greater than the control or TRA-8-treated mice. A trend toward improved survival was observed between TRA-8/Tmz/RT-treated and Tmz/RT-treated mice. Conclusions: These preliminary findings support the hypothesis that TRA-8 will augment the RT and chemotherapy response in gliomas. A humanized version of TRA-8 is being evaluated in a Phase II clinical trial.

  12. Bevacizumab and Temozolomide Plus Radiation Regimen for Glioblastoma Multiforme

    PubMed Central

    Rutledge, Matthew R.; Waddell, J. Aubrey; Solimando, Dominic A.

    2015-01-01

    The complexity of cancer chemotherapy requires pharmacists be familiar with the complicated regimens and highly toxic agents used. This column reviews various issues related to preparation, dispensing, and administration of antineoplastic therapy, and the agents, both commercially available and investigational, used to treat malignant diseases. Questions or suggestions for topics should be addressed to Dominic A. Solimando, Jr, President, Oncology Pharmacy Services, Inc., 4201 Wilson Blvd #110-545, Arlington, VA 22203, e-mail: OncRxSvc@comcast.net; or J. Aubrey Waddell, Professor, University of Tennessee College of Pharmacy; Oncology Pharmacist, Pharmacy Department, Blount Memorial Hospital, 907 E. Lamar Alexander Parkway, Maryville, TN 37804, e-mail: waddfour@charter.net. PMID:26823616

  13. Feasibility of Using Bevacizumab With Radiation Therapy and Temozolomide in Newly Diagnosed High-Grade Glioma

    SciTech Connect

    Narayana, Ashwatha Golfinos, John G.; Fischer, Ingeborg; Raza, Shahzad; Kelly, Patrick M.D.; Parker, Erik; Knopp, Edmond A.; Medabalmi, Praveen; Zagzag, David; Eagan, Patricia; Gruber, Michael L.

    2008-10-01

    Introduction: Bevacizumab, a monoclonal antibody against vascular endothelial growth factor (VEGF), has shown promise in the treatment of patients with recurrent high-grade glioma. The purpose of this study is to test the feasibility of using bevacizumab with chemoradiation in the primary management of high-grade glioma. Methods and Materials: Fifteen patients with high-grade glioma were treated with involved field radiation therapy to a dose of 59.4 Gy at 1.8 Gy/fraction with bevacizumab 10 mg/kg on Days 14 and 28 and temozolomide 75 mg/m{sup 2}. Subsequently, bevacizumab 10 mg/kg was continued every 2 weeks with temozolomide 150 mg/m{sup 2} for 12 months. Changes in relative cerebral blood volume, perfusion-permeability index, and tumor volume measurement were measured to assess the therapeutic response. Immunohistochemistry for phosphorylated VEGF receptor 2 (pVEGFR2) was performed. Results: Thirteen patients (86.6%) completed the planned bevacizumab and chemoradiation therapy. Four Grade III/IV nonhematologic toxicities were seen. Radiographic responses were noted in 13 of 14 assessable patients (92.8%). The pVEGFR2 staining was seen in 7 of 8 patients (87.5%) at the time of initial diagnosis. Six patients have experienced relapse, 3 at the primary site and 3 as diffuse disease. One patient showed loss of pVEGFR2 expression at relapse. One-year progression-free survival and overall survival rates were 59.3% and 86.7%, respectively. Conclusion: Use of antiangiogenic therapy with radiation and temozolomide in the primary management of high-grade glioma is feasible. Perfusion imaging with relative cerebral blood volume, perfusion-permeability index, and pVEGFR2 expression may be used as a potential predictor of therapeutic response. Toxicities and patterns of relapse need to be monitored closely.

  14. Metronomic temozolomide as second line treatment for metastatic poorly differentiated pancreatic neuroendocrine carcinoma.

    PubMed

    De Divitiis, C; von Arx, C; Grimaldi, A M; Cicala, D; Tatangelo, F; Arcella, A; Romano, G M; Simeone, E; Iaffaioli, R V; Ascierto, P A; Tafuto, S

    2016-01-01

    Neuroendocrine Neoplasms (NEN) are a group of heterogeneous malignancies derived from neuroendocrine cell compartment, with different roles in both endocrine and nervous system. Most NETs have gastroentero-pancreatic (GEP) origin, arising in the foregut, midgut, or hindgut. The 2010 WHO classification divides GEP-NETs into two main subgroups, neuroendocrine tumors (NET) and neuroendocrine carcinomas (NEC), according with Ki-67 levels. NET are tumors with low (<20 %) Ki-67 value, and NECs, including small cell lung carcinomas and Merkel Cell carcinomas, are all NETs with high Ki-67 levels (>20 %-G3). Poorly differentiated neuroendocrine carcinomas (NEC) are usually treated with cisplatin-based chemotherapy regimens. Here we present a case of a patient with pancreatic NEC progressing after cisplatin and etoposide, treated with temozolomide as palliative, second line treatment. According with the poor Performance Status (PS = 2) and to reduce the toxicity of the treatment was chosen an intermittent dosing regimen of metronomic temozolomide (75 mg/m(2)/day-one-week-on/on-week-off). MGMT resulted methylated. On July 2014 the patient started the treatment. On August 2014 the patient obtained a significant clinical benefit (PS = 0) and the total body CT scan performed on October 2014 showed a RECIST partial response on all the sites of disease. No drug-related side effects were reported by the patient. After 18 months of therapy the treatment continues without significant toxicity, and with further remission of the metastases. Treatment with metronomic "one-week-on/on-week-off" Temozolomide can be considered a good treatment option in patients with poor performance status, affected by pNEC with MGMT methylation. PMID:27142424

  15. Synergistic Effects of Crizotinib and Temozolomide in Experimental FIG-ROS1 Fusion-Positive Glioblastoma.

    PubMed

    Das, Arabinda; Cheng, Ron Ron; Hilbert, Megan L T; Dixon-Moh, Yaenette N; Decandio, Michele; Vandergrift, William Alex; Banik, Naren L; Lindhorst, Scott M; Cachia, David; Varma, Abhay K; Patel, Sunil J; Giglio, Pierre

    2015-01-01

    Glioblastoma (GB) is the most common malignant brain tumor. Drug resistance frequently develops in these tumors during chemotherapy. Therefore, predicting drug response in these patients remains a major challenge in the clinic. Thus, to improve the clinical outcome, more effective and tolerable combination treatment strategies are needed. Robust experimental evidence has shown that the main reason for failure of treatments is signal redundancy due to coactivation of several functionally linked receptor tyrosine kinases (RTKs), including anaplastic lymphoma kinase (ALK), c-Met (hepatocyte growth factor receptor), and oncogenic c-ros oncogene1 (ROS1: RTK class orphan) fusion kinase FIG (fused in GB)-ROS1. As such, these could be attractive targets for GB therapy. The study subjects consisted of 19 patients who underwent neurosurgical resection of GB tissues. Our in vitro and ex vivo models promisingly demonstrated that treatments with crizotinib (PF-02341066: dual ALK/c-Met inhibitor) and temozolomide in combination induced synergistic antitumor activity on FIG-ROS1-positive GB cells. Our results also showed that ex vivo FIG-ROS1+ slices (obtained from GB patients) when cultured were able to preserve tissue architecture, cell viability, and global gene-expression profiles for up to 14 days. Both in vitro and ex vivo studies indicated that combination blockade of FIG, p-ROS1, p-ALK, and p-Met augmented apoptosis, which mechanistically involves activation of Bim and inhibition of survivin, p-Akt, and Mcl-1 expression. However, it is important to note that we did not see any significant synergistic effect of crizotinib and temozolomide on FIG-ROS1-negative GB cells. Thus, these ex vivo culture results will have a significant impact on patient selection for clinical trials and in predicting response to crizotinib and temozolomide therapy. Further studies in different animal models of FIG-ROS1-positive GB cells are warranted to determine useful therapies for the

  16. Synergistic Effects of Crizotinib and Temozolomide in Experimental FIG-ROS1 Fusion-Positive Glioblastoma

    PubMed Central

    Das, Arabinda; Cheng, Ron Ron; Hilbert, Megan L.T.; Dixon-Moh, Yaenette N.; Decandio, Michele; Vandergrift, William Alex; Banik, Naren L.; Lindhorst, Scott M.; Cachia, David; Varma, Abhay K.; Patel, Sunil J.; Giglio, Pierre

    2015-01-01

    Glioblastoma (GB) is the most common malignant brain tumor. Drug resistance frequently develops in these tumors during chemotherapy. Therefore, predicting drug response in these patients remains a major challenge in the clinic. Thus, to improve the clinical outcome, more effective and tolerable combination treatment strategies are needed. Robust experimental evidence has shown that the main reason for failure of treatments is signal redundancy due to coactivation of several functionally linked receptor tyrosine kinases (RTKs), including anaplastic lymphoma kinase (ALK), c-Met (hepatocyte growth factor receptor), and oncogenic c-ros oncogene1 (ROS1: RTK class orphan) fusion kinase FIG (fused in GB)-ROS1. As such, these could be attractive targets for GB therapy. The study subjects consisted of 19 patients who underwent neurosurgical resection of GB tissues. Our in vitro and ex vivo models promisingly demonstrated that treatments with crizotinib (PF-02341066: dual ALK/c-Met inhibitor) and temozolomide in combination induced synergistic antitumor activity on FIG-ROS1-positive GB cells. Our results also showed that ex vivo FIG-ROS1+ slices (obtained from GB patients) when cultured were able to preserve tissue architecture, cell viability, and global gene-expression profiles for up to 14 days. Both in vitro and ex vivo studies indicated that combination blockade of FIG, p-ROS1, p-ALK, and p-Met augmented apoptosis, which mechanistically involves activation of Bim and inhibition of survivin, p-Akt, and Mcl-1 expression. However, it is important to note that we did not see any significant synergistic effect of crizotinib and temozolomide on FIG-ROS1-negative GB cells. Thus, these ex vivo culture results will have a significant impact on patient selection for clinical trials and in predicting response to crizotinib and temozolomide therapy. Further studies in different animal models of FIG-ROS1-positive GB cells are warranted to determine useful therapies for the

  17. Relapse of herpes encephalitis induced by temozolomide-based chemoradiation in a patient with malignant glioma.

    PubMed

    Okada, Masaki; Miyake, Keisuke; Shinomiya, Aya; Kawai, Nobuyuki; Tamiya, Takashi

    2013-02-01

    The authors report on a case of concurrent herpes simplex encephalitis (HSE) and malignant glioma. The co-occurrence of HSE and malignant glioma is very rare, but it can occur during glioma treatment. Both radiotherapy and chemoradiation with temozolomide can induce viral reactivation, leading to HSE relapse. Careful observation for HSE is necessary when administering chemoradiation to patients with a history of HSE. Antiviral therapy for HSE must be initiated immediately, and the chemoradiation for glioma should be stopped; however, it is not clear what antitumor therapy is optimal when HSE co-occurs during the treatment of glioma.

  18. Analysis of potential response predictors to capecitabine/temozolomide in metastatic pancreatic neuroendocrine tumors.

    PubMed

    Cives, M; Ghayouri, M; Morse, B; Brelsford, M; Black, M; Rizzo, A; Meeker, A; Strosberg, J

    2016-09-01

    The capecitabine and temozolomide (CAPTEM) regimen is active in the treatment of metastatic pancreatic neuroendocrine tumors (pNETs), with response rates ranging from 30 to 70%. Small retrospective studies suggest that O(6)-methylguanine DNA methyltransferase (MGMT) deficiency predicts response to temozolomide. High tumor proliferative activity is also commonly perceived as a significant predictor of response to cytotoxic chemotherapy. It is unclear whether chromosomal instability (CIN), which correlates with alternative lengthening of telomeres (ALT), is a predictive factor. In this study, we evaluated 143 patients with advanced pNET who underwent treatment with CAPTEM for radiographic and biochemical response. MGMT expression (n=52), grade (n=128) and ALT activation (n=46) were investigated as potential predictive biomarkers. Treatment with CAPTEM was associated with an overall response rate (ORR) of 54% by RECIST 1.1. Response to CAPTEM was not influenced by MGMT expression, proliferative activity or ALT pathway activation. Based on these results, no biomarker-driven selection criteria for use of the CAPTEM regimen can be recommended at this time.

  19. Radiologic response to radiation therapy concurrent with temozolomide for progressive simple dysembryoplastic neuroepithelial tumor.

    PubMed

    Morr, Simon; Qiu, Jingxin; Prasad, Dheerendra; Mechtler, Laszlo L; Fenstermaker, Robert A

    2016-07-01

    Dysembryoplastic neuroepithelial tumors (DNETs) are low-grade neuroglial tumors that are traditionally considered to be benign hamartoma-like mass lesions. Malignant transformation and disease progression have been reported in complex DNETs. We report a case of a simple DNET with disease progression following subtotal resection. A 34-year-old woman underwent craniotomy with subtotal resection of a large nonenhancing right temporal lobe and insular mass. Histopathological analysis revealed a simple DNET. Magnetic resonance imaging obtained 6 months after surgery demonstrated disease progression with no enhancement or change in signal characteristics. Following concurrent therapy with temozolomide and external beam radiation therapy, a significant radiologic response was observed. Progressive DNET with malignant transformation exhibits predominantly glial transformation and occurs predominantly in complex DNETs. The histological classification of DNETs into simple, complex, and nonspecific are reviewed. Contrast-enhancing regions are more frequently seen in complex tumors, with nonenhancing regions having fewer complex histologic features. Close clinical and radiographic follow-up is important in all cases of DNET. Following tumor progression, radiation therapy with concurrent and adjuvant temozolomide chemotherapy may be an effective treatment.

  20. Temozolomide (Temodar®) and capecitabine (Xeloda®) treatment of an aggressive corticotroph pituitary tumor

    PubMed Central

    Thearle, Marie S.; Bruce, Jeffrey N.; Isaacson, Steven R.; Lee, Yoomi

    2010-01-01

    Only rarely do corticotroph pituitary tumors become invasive leading to symptoms caused by compression of cranial nerves and other local structures. When aggressive pituitary neuroendocrine tumors do develop, conventional treatment options are of limited success. A 50-year-old man developed a giant invasive corticotroph pituitary tumor 2 years after initial presentation. His tumor and symptoms failed to respond to maximal surgical, radio-surgical, radiation and medical therapy and a bilateral adrenalectomy was done. He subsequently developed rapid growth of his tumor leading to multiple cranial nerve deficits. He was administered salvage chemotherapy with capecitabine and temozolomide (CAPTEM), a novel oral chemotherapy regimen developed at our institution for treatment of neuroendocrine tumors. After two cycles of CAPTEM, his tumor markedly decreased in size and ACTH levels fell by almost 90%. Despite further decreases in ACTH levels, his tumor recurred after 5 months with increased avidity on PET scan suggesting a transformation to a more aggressive phenotype. Temozolomide had been reported to be effective against other pituitary tumors and this case adds to this literature demonstrating its use along with capecitabine (CAPTEM) against a corticotroph tumor. Further evaluation of the CAPTEM regimen in patients with pituitary neuroendocrine tumors which fail to respond to classic treatments is warranted. PMID:19960369

  1. Phase II trial of temozolomide and reirradiation using conformal 3D-radiotherapy in recurrent brain gliomas

    PubMed Central

    2014-01-01

    Purpose This phase II trial was designed to assess the response rate, survival benefits and toxicity profile of temozolomide, and brain reirradiation using conformal radiotherapy (RT) for treatment of recurrent high grade glioma. Design Open-label phase II trial. Patients Twenty-nine patients had been enrolled in the study between February 2006 and June 2009. Patients had to show unequivocal evidence of tumour recurrence on gadolinium-enhanced magnetic resonance imaging (MRI) after failing conventional RT with or without temozolomide and surgery for initial disease. Histology included recurrent anaplastic astrocytoma, glioblastoma multiforme. Interventions Patients were treated by temozolomide at a dose of 200 mg/m2/day for chemonaïve patients, and at a dose of 150 mg/m2/day to previously treated patients, for 4-5 cycles. Then, patients underwent reirradiation by conformal RT at a dose of 30-40 Gy by conventional fractionation. Main outcome measures The primary end point of the study was response. The secondary end points included survival benefit. Results All the 29 patients were treated with temozolomide and reirradiation. Two patients achieved complete remission (CR), 4 achieved partial remission (PR), with an overall objective response rate of 20.6%, and further 10 patients had stable disease (SD), with a SD rate of 34.4%. The mean progression free survival (PFS) was 10.1 months, and the mean overall survival (OS) was 11.4 months. Additionally, treatment significantly improved quality of life (QOL). Treatment was tolerated well with mild grade 1, 2 nausea/vomiting in 40% of cycles, and mild grade 1, 2 haematological toxicities (neutropenia/thrombocytoprnia) in 8.6% of cycles. Conclusions Temozolomide and conformal RT had an anti-tumor activity in recurrent high grade glioma, and represented a good treatment hope for patients with recurrent brain glioma. PMID:25333019

  2. Addition of Bevacizumab to Standard Radiation Therapy and Daily Temozolomide Is Associated With Minimal Toxicity in Newly Diagnosed Glioblastoma Multiforme

    SciTech Connect

    Vredenburgh, James J.; Desjardins, Annick; Kirkpatrick, John P.; Reardon, David A.; Peters, Katherine B.; Herndon, James E.; Marcello, Jennifer; Bailey, Leighann; Threatt, Stevie; Sampson, John; Friedman, Allan; Friedman, Henry S.

    2012-01-01

    Purpose: To determine the safety of the addition of bevacizumab to standard radiation therapy and daily temozolomide for newly diagnosed glioblastoma multiforme (GBM). Methods and Materials: A total of 125 patients with newly diagnosed GBM were enrolled in the study, and received standard radiation therapy and daily temozolomide. All patients underwent a craniotomy and were at least 2 weeks postoperative. Radiation therapy was administered in 1.8-Gy fractions, with the clinical target volume for the primary course treated to a dose of 45 to 50.4 Gy, followed by a boost of 9 to 14.4 Gy, to a total dose of 59.4 Gy. Patients received temozolomide at 75 mg/m{sup 2} daily throughout the course of radiation therapy. Bevacizumab was given at 10 mg/kg intravenously every 14 days, beginning a minimum of 4 weeks postoperatively. Results: Of the 125 patients, 120 (96%) completed the protocol-specified radiation therapy. Five patients had to stop the protocol therapy, 2 patients with pulmonary emboli, and 1 patient each with a Grade 2 central nervous system hemorrhage, Grade 4 pancytopenia, and wound dehiscence requiring surgical intervention. All 5 patients ultimately finished the radiation therapy. After radiation therapy, 3 patients had progressive disease, 2 had severe fatigue and decreased performance status, 1 patient had a colonic perforation, and 1 had a rectal fissure; these 7 patients therefore did not proceed with the protocol-specified adjuvant temozolomide, bevacizumab, and irinotecan. However, 113 patients (90%) were able to continue on study. Conclusions: The addition of bevacizumab to standard radiation therapy and daily temozolomide was found to be associated with minimal toxicity in patients newly diagnosed with GBM.

  3. Veliparib and Temozolomide in Treating Patients With Acute Leukemia

    ClinicalTrials.gov

    2016-07-20

    Accelerated Phase of Disease; Acute Myeloid Leukemia Arising From Previous Myelodysplastic Syndrome; Adult Acute Myeloid Leukemia With Inv(16)(p13.1q22); CBFB-MYH11; Adult Acute Myeloid Leukemia With t(16;16)(p13.1;q22); CBFB-MYH11; Adult Acute Myeloid Leukemia With t(8;21)(q22;q22); RUNX1-RUNX1T1; Adult Acute Myeloid Leukemia With t(9;11)(p22;q23); MLLT3-MLL; Adult Acute Promyelocytic Leukemia With t(15;17)(q22;q12); PML-RARA; Adult B Acute Lymphoblastic Leukemia; Adult B Acute Lymphoblastic Leukemia With t(9;22)(q34;q11.2); BCR-ABL1; Adult T Acute Lymphoblastic Leukemia; Alkylating Agent-Related Acute Myeloid Leukemia; Blastic Phase; Chronic Myelomonocytic Leukemia; Recurrent Adult Acute Lymphoblastic Leukemia; Recurrent Adult Acute Myeloid Leukemia; Recurrent Disease; Secondary Acute Myeloid Leukemia; Untreated Adult Acute Lymphoblastic Leukemia; Untreated Adult Acute Myeloid Leukemia

  4. Agent Orange

    MedlinePlus

    ... Index Agent Orange Agent Orange Home Facts about Herbicides Veterans' Diseases Birth Defects Benefits Exposure Locations Provider ... millions of gallons of Agent Orange and other herbicides on trees and vegetation during the Vietnam War. ...

  5. In vitro evaluation of combined temozolomide and radiotherapy using X  rays and high-linear energy transfer radiation for glioblastoma.

    PubMed

    Barazzuol, Lara; Jena, Raj; Burnet, Neil G; Jeynes, Jonathan C G; Merchant, Michael J; Kirkby, Karen J; Kirkby, Norman F

    2012-05-01

    High-linear energy transfer radiation offers superior biophysical properties over conventional radiotherapy and may have a great potential for treating radioresistant tumors, such as glioblastoma. However, very little pre-clinical data exists on the effects of high-LET radiation on glioblastoma cell lines and on the concomitant application of chemotherapy. This study investigates the in vitro effects of temozolomide in combination with low-energy protons and α particles. Cell survival, DNA damage and repair, and cell growth were examined in four human glioblastoma cell lines (LN18, T98G, U87 and U373) after treatment with either X rays, protons (LET 12.91 keV/μm), or α particles (LET 99.26 keV/μm) with or without concurrent temozolomide at clinically-relevant doses of 25 and 50 μM. The relative biological effectiveness at 10% survival (RBE(10)) increased as LET increased: 1.17 and 1.06 for protons, and 1.84 and 1.68 for α particles in the LN18 and U87 cell lines, respectively. Temozolomide administration increased cell killing in the O(6)-methylguanine DNA methyltransferase-methylated U87 and U373 cell lines. In contrast, temozolomide provided no therapeutic enhancement in the methylguanine DNA methyltransferase-unmethylated LN18 and T98G cell lines. In addition, the residual number of γ-H2AX foci at 24 h after treatment with radiation and concomitant temozolomide was found to be lower than or equal to that expected by DNA damage with either of the individual treatments. Kinetics of foci disappearance after X-ray and proton irradiation followed similar time courses; whereas, loss of γ-H2AX foci after α particle irradiation occurred at a slower rate than that by low-LET radiation (half-life 12.51-16.87 h). The combination of temozolomide with different radiation types causes additive rather than synergistic cytotoxicity. Nevertheless, particle therapy combined with chemotherapy may offer a promising alternative with the additional benefit of superior

  6. Patterns and Timing of Recurrence After Temozolomide-Based Chemoradiation for Glioblastoma

    SciTech Connect

    Milano, Michael T.; Okunieff, Paul; Donatello, Rosemary S.; Mohile, Nimish A.; Sul, Joohee; Walter, Kevin A.; Korones, David N.

    2010-11-15

    Purpose: To determine recurrence patterns of glioblastoma treated with temozolomide-based chemoradiation. Methods: Pretreatment and serial posttreatment magnetic resonance imaging scans of 54 patients were retrospectively evaluated. Central recurrence (i.e., local progression) and the development of new (i.e., interval appearance of discrete enhancing lesion) in-field, marginal, and distant recurrences were assessed, with the pattern of recurrence of individual lesions defined relative to the 95% isodose line (D{sub 95}). Distant recurrences were defined as lesions completely outside D{sub 95}, marginal recurrences crossed D{sub 95}, and in-field recurrences were completely inside D{sub 95}. Results: At a median follow-up of 17 months, 39 of 54 (72%) patients developed recurrent glioblastoma. Among these 39 patients, central recurrence occurred in 80% (at a median of 7 months from diagnosis); new in-field recurrence developed in 33% (at a median of 14 months); marginal recurrences developed in 15% (at a median of 18 months); and distant recurrences developed in 20% (at a median of 11 months). The actuarial rates of central, new in-field, marginal, distant, and any new recurrences at 1-year were 46%, 15%, 3%, 14%, and 25% respectively, whereas at 2 years, the rates were 68%, 60%, 32%, 28%, and 66%, reflecting an increasing probability of new lesions developing at later time points. Ten patients developed subependymal recurrences, of whom 7 developed multiple subependymal lesions. Conclusions: Whereas central recurrence of glioblastoma treated with radiation and temozolomide predominates and persists over time, new in-field, marginal, and distant recurrences commonly develop, particularly at later time points in patients with longer survival.

  7. Successful change of treatment strategy in elderly patients with primary central nervous system lymphoma by de-escalating induction and introducing temozolomide maintenance: results from a phase II study by the Nordic Lymphoma Group.

    PubMed

    Pulczynski, Elisa J; Kuittinen, Outi; Erlanson, Martin; Hagberg, Hans; Fosså, Alexander; Eriksson, Mikael; Nordstrøm, Marie; Østenstad, Bjørn; Fluge, Øystein; Leppä, Sirpa; Fiirgaard, Bente; Bersvendsen, Hanne; Fagerli, Unn-Merete

    2015-04-01

    The Nordic Lymphoma Group has conducted a phase ll trial in newly diagnosed primary central nervous system lymphoma patients applying an age-adjusted multi-agent immunochemotherapy regimen, which in elderly patients included temozolomide maintenance treatment. Patients aged 18-75 years were eligible. Thirty-nine patients aged 18-65 years and 27 patients aged 66-75 years were enrolled. The median age of the two age groups was 55 and 70 years, respectively. The overall response rate was 73.8% for the entire cohort: 69.9% in the younger and 80.8% in the elderly subgroup. With a median follow up of 22 months, the 2-year overall survival probability was 60.7% in patients aged 65 years or under and 55.6% in patients aged over 65 years (P=0.40). The estimated progression-free survival at two years was 33.1% (95%CI: 19.1%-47.9%) in patients aged under 65 years and 44.4% (95%CI: 25.6%-61.8%) in the elderly subgroup (P=0.74). Median duration of response was ten months in the younger subgroup, and not reached in the elderly patient subgroup (P=0.33). Four patients aged 64-75 years (6%) died from treatment-related complications. Survival in the two age groups was similar despite a de-escalation of induction treatment in patients aged over 65 years. Duration of response in elderly patients receiving maintenance temozolomide was longer than in the younger age subgroup. While toxicity during induction is still of concern, especially in the elderly patients, we conclude from these data that de-escalation of induction therapy in elderly primary central nervous system lymphoma patients followed by maintenance treatment seems to be a promising treatment strategy. (clinicaltrials.gov identifier:01458730). PMID:25480497

  8. Successful change of treatment strategy in elderly patients with primary central nervous system lymphoma by de-escalating induction and introducing temozolomide maintenance: results from a phase II study by the Nordic Lymphoma Group.

    PubMed

    Pulczynski, Elisa J; Kuittinen, Outi; Erlanson, Martin; Hagberg, Hans; Fosså, Alexander; Eriksson, Mikael; Nordstrøm, Marie; Østenstad, Bjørn; Fluge, Øystein; Leppä, Sirpa; Fiirgaard, Bente; Bersvendsen, Hanne; Fagerli, Unn-Merete

    2015-04-01

    The Nordic Lymphoma Group has conducted a phase ll trial in newly diagnosed primary central nervous system lymphoma patients applying an age-adjusted multi-agent immunochemotherapy regimen, which in elderly patients included temozolomide maintenance treatment. Patients aged 18-75 years were eligible. Thirty-nine patients aged 18-65 years and 27 patients aged 66-75 years were enrolled. The median age of the two age groups was 55 and 70 years, respectively. The overall response rate was 73.8% for the entire cohort: 69.9% in the younger and 80.8% in the elderly subgroup. With a median follow up of 22 months, the 2-year overall survival probability was 60.7% in patients aged 65 years or under and 55.6% in patients aged over 65 years (P=0.40). The estimated progression-free survival at two years was 33.1% (95%CI: 19.1%-47.9%) in patients aged under 65 years and 44.4% (95%CI: 25.6%-61.8%) in the elderly subgroup (P=0.74). Median duration of response was ten months in the younger subgroup, and not reached in the elderly patient subgroup (P=0.33). Four patients aged 64-75 years (6%) died from treatment-related complications. Survival in the two age groups was similar despite a de-escalation of induction treatment in patients aged over 65 years. Duration of response in elderly patients receiving maintenance temozolomide was longer than in the younger age subgroup. While toxicity during induction is still of concern, especially in the elderly patients, we conclude from these data that de-escalation of induction therapy in elderly primary central nervous system lymphoma patients followed by maintenance treatment seems to be a promising treatment strategy. (clinicaltrials.gov identifier:01458730).

  9. A Phase I Study of the Combination of Sorafenib With Temozolomide and Radiation Therapy for the Treatment of Primary and Recurrent High-Grade Gliomas

    SciTech Connect

    Den, Robert B.; Kamrava, Mitchell; Sheng, Zhi; Werner-Wasik, Maria; Dougherty, Erin; Marinucchi, Michelle; Lawrence, Yaacov R.; Hegarty, Sarah; Hyslop, Terry; Andrews, David W.; Glass, Jon; Friedman, David P.; Green, Michael R.; Camphausen, Kevin; Dicker, Adam P.

    2013-02-01

    Purpose: Despite recent advances in the management of high-grade and recurrent gliomas, survival remains poor. Antiangiogenic therapy has been shown to be efficacious in the treatment of high-grade gliomas both in preclinical models and in clinical trials. We sought to determine the safety and maximum tolerated dose of sorafenib when combined with both radiation and temozolomide in the primary setting or radiation alone in the recurrent setting. Methods and Materials: This was a preclinical study and an open-label phase I dose escalation trial. Multiple glioma cell lines were analyzed for viability after treatment with radiation, temozolomide, or sorafenib or combinations of them. For patients with primary disease, sorafenib was given concurrently with temozolomide (75 mg/m{sup 2}) and 60 Gy radiation, for 30 days after completion of radiation. For patients with recurrent disease, sorafenib was combined with a hypofractionated course of radiation (35 Gy in 10 fractions). Results: Cell viability was significantly reduced with the combination of radiation, temozolomide, and sorafenib or radiation and sorafenib. Eighteen patients (11 in the primary cohort, 7 in the recurrent cohort) were enrolled onto this trial approved by the institutional review board. All patients completed the planned course of radiation therapy. The most common toxicities were hematologic, fatigue, and rash. There were 18 grade 3 or higher toxicities. The median overall survival was 18 months for the entire population. Conclusions: Sorafenib can be safely combined with radiation and temozolomide in patients with high-grade glioma and with radiation alone in patients with recurrent glioma. The recommended phase II dose of sorafenib is 200 mg twice daily when combined with temozolomide and radiation and 400 mg with radiation alone. To our knowledge, this is the first publication of concurrent sorafenib with radiation monotherapy or combined with radiation and temozolomide.

  10. Phase II Trial of Pre-Irradiation and Concurrent Temozolomide in Patients with Newly Diagnosed Anaplastic Oligodendrogliomas and Mixed Anaplastic Oligoastrocytomas: Long Term Results of RTOG BR0131

    PubMed Central

    Vogelbaum, Michael A.; Hu, Chen; Peereboom, David M.; Macdonald, David R.; Giannini, Caterina; Suh, John H.; Jenkins, Robert B.; Laack, Nadia N.; Brachman, David G.; Shrieve, Dennis C.; Souhami, Luis; Mehta, Minesh P.

    2015-01-01

    BACKGROUND We report on the long-term results of a phase II study of pre-irradiation temozolomide followed by concurrent temozolomide and radiotherapy (RT) in patients with newly diagnosed anaplastic oligodendroglioma (AO) and mixed anaplastic oligoastrocytoma (MOA). METHODS Pre-RT temozolomide was given for up to 6 cycles. RT with concurrent temozolomide was administered to patients with less than a complete radiographic response. RESULTS Forty eligible patients were entered and 32 completed protocol treatment. With a median follow-up time of 8.7 years (range: 1.1 to 10.1), median progression-free survival (PFS) is 5.8 years (95% C.I. 2.0, NR) and median overall survival (OS) has not been reached (5.9, NR). 1p/19q data are available in 37 cases; 23 tumors had codeletion while 14 tumors had no loss or loss of only 1p or 19q (non-codeleted). In codeleted patients, 9 patients have progressed and 4 have died; neither median PFS nor OS have been reached and two patients who received only pre-RT temozolomide and no RT have remained progression-free for over 7 years. 3-year PFS and 6-year OS are 78% (95% CI: 61-95%) and 83% (95% CI: 67-98%), respectively. Codeleted patients show a trend towards improved 6-year survival when compared to the codeleted procarbazine/CCNU/vincristrine (PCV) and RT cohort in RTOG 9402 (67%, 95% CI:55-79%). For non-codeleted patients, median PFS and OS are 1.3 and 5.8 years, respectively. CONCLUSIONS These updated results suggest that the regimen of dose intense, pre-RT temozolomide followed by concurrent RT/temozolomide has significant activity, particularly in patients with 1p/19q codeleted AOs and MAOs. PMID:26088460

  11. The multidrug-resistance transporter Abcc3 protects NK cells from chemotherapy in a murine model of malignant glioma

    PubMed Central

    Pessina, Sara; Cantini, Gabriele; Kapetis, Dimos; Cazzato, Emanuela; Di Ianni, Natalia; Finocchiaro, Gaetano; Pellegatta, Serena

    2016-01-01

    ABSTRACT Abcc3, a member of the ATP-binding cassette transporter superfamily, plays a role in multidrug resistance. Here, we found that Abcc3 is highly expressed in blood-derived NK cells but not in CD8+ T cells. In GL261 glioma-bearing mice treated with the alkylating agent temozolomide (TMZ) for 5 d, an early increased frequency of NK cells was observed. We also found that Abcc3 is strongly upregulated and functionally active in NK cells from mice treated with TMZ compared to controls. We demonstrate that Abcc3 is critical for NK cell survival during TMZ administration; more importantly, Akt, involved in lymphocyte survival, is phosphorylated only in NK cells expressing Abcc3. The resistance of NK cells to chemotherapy was accompanied by increased migration and homing in the brain at early time points. Cytotoxicity, evaluated by IFNγ production and specific lytic activity against GL261 cells, increased peripherally in the later phases, after conclusion of TMZ treatment. Intra-tumor increase of the NK effector subset as well as in IFNγ, granzymes and perforin-1 expression, were found early and persisted over time, correlating with a profound modulation on glioma microenvironment induced by TMZ. Our findings reveal an important involvement of Abcc3 in NK cell resistance to chemotherapy and have important clinical implications for patients treated with chemo-immunotherapy. PMID:27467914

  12. The Medicinal Chemistry of Imidazotetrazine Prodrugs

    PubMed Central

    Moody, Catherine L.; Wheelhouse, Richard T

    2014-01-01

    Temozolomide (TMZ) is the standard first line treatment for malignant glioma, reaching “blockbuster” status in 2010, yet it remains the only drug in its class. The main constraints on the clinical effectiveness of TMZ therapy are its requirement for active DNA mismatch repair (MMR) proteins for activity, and inherent resistance through O6-methyl guanine-DNA methyl transferase (MGMT) activity. Moreover, acquired resistance, due to MMR mutation, results in aggressive TMZ-resistant tumour regrowth following good initial responses. Much of the attraction in TMZ as a drug lies in its PK/PD properties: it is acid stable and has 100% oral bioavailability; it also has excellent distribution properties, crosses the blood-brain barrier, and there is direct evidence of tumour localisation. This review seeks to unravel some of the mysteries of the imidazotetrazine class of compounds to which TMZ belongs. In addition to an overview of different synthetic strategies, we explore the somewhat unusual chemical reactivity of the imidazotetrazines, probing their mechanisms of reaction, examining which attributes are required for an active drug molecule and reviewing the use of this combined knowledge towards the development of new and improved anti-cancer agents. PMID:25014631

  13. Phase I Clinical Trial Assessing Temozolomide and Tamoxifen With Concomitant Radiotherapy for Treatment of High-Grade Glioma

    SciTech Connect

    Patel, Shilpen; DiBiase, Steven; Meisenberg, Barry; Flannery, Todd; Patel, Ashish; Dhople, Anil; Cheston, Sally; Amin, Pradip

    2012-02-01

    Purpose: The new standard treatment of glioblastoma multiforme is concurrent radiotherapy (RT) and temozolomide. The proliferation of high-grade gliomas might be partly dependent on protein kinase C-mediated pathways. Tamoxifen has been shown in vitro to inhibit protein kinase C through estrogen receptor-independent antineoplastic effects. This Phase I trial was designed to determine the maximal tolerated dose (MTD) of tamoxifen when given with temozolomide and concurrent RT to patients with high-grade gliomas. Methods and Materials: A total of 17 consecutive patients in four cohorts with World Health Organization Grade 3 (n = 2) and 4 (n = 15) gliomas were given tamoxifen twice daily during 6 weeks of concurrent RT and temozolomide. Eligibility included histologic diagnosis, age >18 years old, Karnofsky performance status {>=}60, and no previous brain RT or chemotherapy. The starting dose was 50 mg/m{sup 2} divided twice daily. If no dose-limiting toxicities (DLTs) occurred in 3 patients, the dose was escalated in 25-mg/m{sup 2} increments until the MTD was reached. When {>=}2 patients within a cohort experienced a DLT, the MTD had been exceeded. Temozolomide was given with RT at 75 mg/m{sup 2}. A dose of 60 Gy in 2 Gy/d fractions to a partial brain field was delivered. Results: A total of 6 patients in Cohort 4 had received tamoxifen at 125 mg/m{sup 2}. One patient was excluded, and the fourth patient developed Grade 4 thrombocytopenia (DLT). Thus, 3 more patients needed to be enrolled. A deep venous thrombosis (DLT) occurred in the sixth patient. Thus, the MTD was 100 mg/m{sup 2}. Conclusions: The MTD of tamoxifen was 100 mg/m{sup 2} when given concurrently with temozolomide 75 mg/m{sup 2} and RT. Tamoxifen might have a role in the initial treatment of high-grade gliomas and should be studied in future Phase II trials building on the newly established platform of concurrent chemoradiotherapy.

  14. Phase I study of temozolomide in combination with thiotepa and carboplatin with autologous hematopoietic cell rescue in patients with malignant brain tumors with minimal residual disease.

    PubMed

    Egan, G; Cervone, K A; Philips, P C; Belasco, J B; Finlay, J L; Gardner, S L

    2016-04-01

    Recurrence of malignant brain tumors results in a poor prognosis with limited treatment options. High-dose chemotherapy with autologous hematopoietic cell rescue (AHCR) has been used in patients with recurrent malignant brain tumors and has shown improved outcomes compared with standard chemotherapy. Temozolomide is standard therapy for glioblastoma and has also shown activity in patients with medulloblastoma/primitive neuro-ectodermal tumor (PNET), particularly those with recurrent disease. Temozolomide was administered twice daily on days -10 to -6, followed by thiotepa 300 mg/m(2) per day and carboplatin dosed using the Calvert formula or body surface area on days -5 to -3, with AHCR day 0. Twenty-seven patients aged 3-46 years were enrolled. Diagnoses included high-grade glioma (n=12); medulloblastoma/PNET (n=9); central nervous system (CNS) germ cell tumor (n=4); ependymoma (n=1) and spinal cord PNET (n=1). Temozolomide doses ranged from 100 mg/m(2) per day to 400 mg/m(2) per day. There were no toxic deaths. Prolonged survival was noted in several patients including those with recurrent high-grade glioma, medulloblastoma and CNS germ cell tumor. Increased doses of temozolomide are feasible with AHCR. A phase II study using temozolomide, carboplatin and thiotepa with AHCR for children with recurrent malignant brain tumors is being conducted through the Pediatric Blood and Marrow Transplant Consortium. PMID:26726947

  15. Temozolomide 3 weeks on and 1 week off as first-line therapy for recurrent glioblastoma: phase II study from gruppo italiano cooperativo di neuro-oncologia (GICNO).

    PubMed

    Brandes, A A; Tosoni, A; Cavallo, G; Bertorelle, R; Gioia, V; Franceschi, E; Biscuola, M; Blatt, V; Crinò, L; Ermani, M

    2006-11-01

    The efficacy of temozolomide strongly depends on O(6)-alkylguanine DNA-alkyl transferase (AGAT), which repairs DNA damage caused by the drug itself. Low-dose protracted temozolomide administration can decrease AGAT activity. The main end point of the present study was therefore to test progression-free survival at 6 months (PFS-6) in glioblastoma patients following a prolonged temozolomide schedule. Chemonaïve glioblastoma patients with disease recurrence or progression after surgery and standard radiotherapy were considered eligible. Chemotherapy cycles consisted of temozolomide 75 mg/m(2)/daily for 21 days every 28 days until disease progression. O(6)-methyl-guanine-DNA-methyl-tranferase (MGMT) was determined in 22 patients (66.7%). A total of 33 patients (median age 57 years, range 31-71) with a median KPS of 90 (range 60-100) were accrued. The overall response rate was 9%, and PFS-6 30.3% (95% CI:18-51%). No correlation was found between the MGMT promoter methylation status of the tumours and the overall response rate, time to progression and survival. In 153 treatment cycles delivered, the most common grade 3/4 event was lymphopoenia. The prolonged temozolomide schedule considered in the present study is followed by a high PFS-6 rate; toxicity is acceptable. Further randomised trials should therefore be conducted to confirm the efficacy of this regimen.

  16. Validation of the Effectiveness and Safety of Temozolomide during and after Radiotherapy for Newly Diagnosed Glioblastomas: 10-year Experience of a Single Institution

    PubMed Central

    Joo, Jin-Deok; Kim, Hansol; Kim, Young-Hoon; Han, Jung Ho

    2015-01-01

    This study was performed to validate the effectiveness and safety of concurrent chemoradiotherapy and adjuvant therapy with temozolomide for newly diagnosed glioblastoma multiforme as a standard treatment protocol. Between 2004 and 2011, patients newly diagnosed with glioblastoma who were treated with temozolomide during concurrent chemoradiotherapy and adjuvant chemotherapy were included from a single institution and analyzed retrospectively. The primary endpoint was overall survival, and the secondary endpoints were progression-free survival, response, and safety. A total of 71 patients were enrolled in this study. The response rate was 41% (29/71), and the tumor control rate was 80% (57/71). In the 67 patients who completed the concurrent chemoradiotherapy with temozolomide, the median overall survival was 19 months and the 1- and 2-yr overall survival rates were 78.3% and 41.7%, respectively. The median progression free survival was 9 months, and the 1- and 2-yr progression free survival rates were 33.8% and 14.3%, respectively. The mean duration of survival after progression of disease in salvage treatment group was 11.9 (1.3-53.2) months. Concurrent chemoradiotherapy with temozolomide resulted in grade 3 or 4 hematologic toxic effects in 2.8% of the patients. The current protocol of temozolomide during and after radiation therapy is both effective and safe and is still appropriate as the standard protocol for treatment of glioblastoma. An active salvage treatment might be required for a better prognosis. PMID:26539003

  17. Biological Agents

    MedlinePlus

    ... to Z Index Contact Us FAQs What's New Biological Agents This page requires that javascript be enabled ... and Health Topics A-Z Index What's New Biological agents include bacteria, viruses, fungi, other microorganisms and ...

  18. A Multicenter, Phase II, Randomized, Noncomparative Clinical Trial of Radiation and Temozolomide with or without Vandetanib in Newly Diagnosed Glioblastoma Patients

    PubMed Central

    Lee, Eudocia Q.; Kaley, Thomas J.; Duda, Dan G.; Schiff, David; Lassman, Andrew B.; Wong, Eric T.; Mikkelsen, Tom; Purow, Benjamin W.; Muzikansky, Alona; Ancukiewicz, Marek; Huse, Jason T.; Ramkissoon, Shakti; Drappatz, Jan; Norden, Andrew D.; Beroukhim, Rameen; Weiss, Stephanie E.; Alexander, Brian M.; McCluskey, Christine S.; Gerard, Mary; Smith, Katrina H.; Jain, Rakesh K.; Batchelor, Tracy T.; Ligon, Keith L.; Wen, Patrick Y.

    2016-01-01

    Purpose Vandetanib, a tyrosine kinase inhibitor of KDR (VEGFR2), EGFR, and RET, may enhance sensitivity to chemotherapy and radiation. We conducted a randomized, noncomparative, phase II study of radiation (RT) and temozolomide with or without vandetanib in patients with newly diagnosed glioblastoma (GBM). Experimental Design We planned to randomize a total of 114 newly diagnosed GBM patients in a ratio of 2:1 to standard RT and temozolomide with (76 patients) or without (38 patients) vandetanib 100 mg daily. Patients with age ≥ 18 years, Karnofsky performance status (KPS) ≥ 60, and not on enzyme-inducing antiepileptics were eligible. Primary end-point was median overall survival (OS) from the date of randomization. Secondary endpoints included median progression-free survival (PFS), 12-month PFS, and safety. Correlative studies included pharmacokinetics as well as tissue and serum biomarker analysis. Results The study was terminated early for futility based on the results of an interim analysis. We enrolled 106 patients (36 in the RT/temozolomide arm and 70 in the vandetanib/RT/temozolomide arm). Median OS was 15.9 months [95% confidence interval (CI), 11.0–22.5 months] in the RT/temozolomide arm and 16.6 months (95% CI, 14.9–20.1 months) in the vandetanib/RT/temozolomide (log-rank P = 0.75). Conclusions The addition of vandetanib at a dose of 100 mg daily to standard chemoradiation in patients with newly diagnosed GBM or gliosarcoma was associated with potential pharmacodynamic biomarker changes and was reasonably well tolerated. However, the regimen did not significantly prolong OS compared with the parallel control arm, leading to early termination of the study. PMID:25910950

  19. Convection enhanced delivery and in vivo imaging of polymeric nanoparticles for the treatment of malignant glioma

    PubMed Central

    Mansour, Nassir; Pytel, Peter; Cahill, Kirk E; Voce, David J; Kang, Shijun; Spretz, Ruben; Welp, Ulrich; Noriega, Sandra E; Nunez, Luis; Larsen, Gustavo F; Weichselbaum, Ralph R.; Yamini, Bakhtiar

    2013-01-01

    A major obstacle to the management of malignant glioma is the inability to effectively deliver therapeutic agent to the tumor. In this study, we describe a polymeric nanoparticle vector that not only delivers viable therapeutic, but can also be tracked in vivo using MRI. Nanoparticles, produced by a non-emulsion technique, were fabricated to carry iron oxide within the shell and the chemotherapeutic agent, temozolomide (TMZ), as the payload. Nanoparticle properties were characterized and subsequently their endocytosis-mediated uptake by glioma cells demonstrated. Convection enhanced delivery (CED) can disperse nanoparticles through the rodent brain and their distribution is accurately visualized by MRI. Infusion of nanoparticles does not result in observable animal toxicity relative to control. CED of TMZ bearing nanoparticles prolongs the survival of animals with intracranial xenografts compared to control. In conclusion, the described nanoparticle vector represents a unique multifunctional platform that can be used for image-guided treatment of malignant glioma. PMID:23891990

  20. Formulation and optimization of temozolomide nanoparticles by 3 factor 2 level factorial design

    PubMed Central

    Jain, Aviral; Jain, Sanjay K.

    2013-01-01

    The aim of this study was to investigate the combined influence of 3 independent variables in the preparation of temozolomide bearing Non-PEGylated and PEGylated nanoparticles by emulsification solvent evaporation method. A 3 factor 2 level design was used to derive a polynomial quadratic model and construct contour plots to predict responses. The independent variables selected were concentration of drug (A), concentration of PLGA/PEG-PLGA (B), PVA concentration in aqueous phase (C) and sonication time (D) and evaluated for percentage drug entrapment (PDE) and particle size (PS). A 34 factorial design was used with 4 factors (A, B, C and D) at 3 levels and experimental trials were performed at all 82 possible combinations. In the present work, 28 runs are considered as the preliminary trials revealed that on increasing drug concentration from 2.5 to 5 mg the percent drug entrapment increases, but on further increasing the drug concentration (i.e., to 7.5 mg) no significant effect on the percent drug entrapment and particle size was observed. The 34 factorial design was used to derive a polynomial quadratic model and construct contour plots to predict responses. Contour plots were constructed to show the effects of A, B, C and D on the PDE and PS. PMID:23719178

  1. Glioma cells escaped from cytotoxicity of temozolomide and vincristine by communicating with human astrocytes.

    PubMed

    Chen, Weiliang; Wang, Donghai; Du, Xinwen; He, Ying; Chen, Songyu; Shao, Qianqian; Ma, Chao; Huang, Bin; Chen, Anjing; Zhao, Peng; Qu, Xun; Li, Xingang

    2015-03-01

    Resistance to chemotherapeutic drugs remains a great obstacle to successful treatment of gliomas. Understanding the mechanism of glioma chemoresistance is conducive to develop effective strategies to overcome resistance. Astrocytes are the major stromal cells in the brain and have been demonstrated to play a key role in the malignant phenotype of gliomas. However, little is known regarding its role in glioma chemoresistance. In our study, we established a co-culture system of human astrocytes and glioma in vitro to simulate tumor microenvironment. Our results showed that astrocytes significantly reduced glioma cell apoptosis induced by the chemotherapeutic drugs temozolomide and vincristine. This protective effect was dependent on direct contact between astrocytes and glioma cells through Cx43-GJC. Moreover, in human glioma specimens, we found astrocytes infiltrating around the tumor, with a reactive appearance, suggesting that these astrocytes would play the same chemoprotective effect on gliomas in vivo. Our results expand the understanding of the interaction between astrocytes and glioma cells and provide a possible explanation for unsatisfactory clinical outcomes of chemotherapeutic drugs. Cx43-GJC between astrocytes and glioma cells may be a potential target for overcoming chemoresistance in gliomas clinically. PMID:25631631

  2. Outcomes in Newly Diagnosed Elderly Glioblastoma Patients after Concomitant Temozolomide Administration and Hypofractionated Radiotherapy

    PubMed Central

    Nguyen, Ludovic T.; Touch, Socheat; Nehme-Schuster, Hélène; Antoni, Delphine; Eav, Sokha; Clavier, Jean-Baptiste; Bauer, Nicolas; Vigneron, Céline; Schott, Roland; Kehrli, Pierre; Noël, Georges

    2013-01-01

    This study aimed to analyze the treatment and outcomes of older glioblastoma patients. Forty-four patients older than 70 years of age were referred to the Paul Strauss Center for chemotherapy and radiotherapy. The median age was 75.5 years old (range: 70–84), and the patients included 18 females and 26 males. The median Karnofsky index (KI) was 70%. The Charlson indices varied from 4 to 6. All of the patients underwent surgery. O6-methylguanine–DNA methyltransferase (MGMT) methylation status was determined in 25 patients. All of the patients received radiation therapy. Thirty-eight patients adhered to a hypofractionated radiation therapy schedule and six patients to a normofractionated schedule. Neoadjuvant, concomitant and adjuvant chemotherapy regimens were administered to 12, 35 and 20 patients, respectively. At the time of this analysis, 41 patients had died. The median time to relapse was 6.7 months. Twenty-nine patients relapsed, and 10 patients received chemotherapy upon relapse. The median overall survival (OS) was 7.2 months and the one- and two-year OS rates were 32% and 12%, respectively. In a multivariate analysis, only the Karnofsky index was a prognostic factor. Hypofractionated radiotherapy and chemotherapy with temozolomide are feasible and acceptably tolerated in older patients. However, relevant prognostic factors are needed to optimize treatment proposals. PMID:24202340

  3. Chemical Screening Identifies EUrd as a Novel Inhibitor Against Temozolomide-Resistant Glioblastoma-Initiating Cells.

    PubMed

    Tsukamoto, Yoshihiro; Ohtsu, Naoki; Echizenya, Smile; Otsuguro, Satoko; Ogura, Ryosuke; Natsumeda, Manabu; Isogawa, Mizuho; Aoki, Hiroshi; Ichikawa, Satoshi; Sakaitani, Masahiro; Matsuda, Akira; Maenaka, Katsumi; Fujii, Yukihiko; Kondo, Toru

    2016-08-01

    Glioblastoma (GBM), one of the most malignant human cancers, frequently recurs despite multimodal treatment with surgery and chemo/radiotherapies. GBM-initiating cells (GICs) are the likely cell-of-origin in recurrences, as they proliferate indefinitely, form tumors in vivo, and are resistant to chemo/radiotherapies. It is therefore crucial to find chemicals that specifically kill GICs. We established temozolomide (the standard medicine for GBM)-resistant GICs (GICRs) and used the cells for chemical screening. Here, we identified 1-(3-C-ethynyl-β-d-ribopentofuranosyl) uracil (EUrd) as a selective drug for targeting GICRs. EUrd induced the death in GICRs more effectively than their parental GICs, while it was less toxic to normal neural stem cells. We demonstrate that the cytotoxic effect of EUrd on GICRs partly depended on the increased expression of uridine-cytidine kinase-like 1 (UCKL1) and the decreased one of 5'-nucleotidase cytosolic III (NT5C3), which regulate uridine-monophosphate synthesis positively and negatively respectively. Together, these findings suggest that EUrd can be used as a new therapeutic drug for GBM with the expression of surrogate markers UCKL1 and NT5C3. Stem Cells 2016;34:2016-2025.

  4. Survival with concurrent temozolomide and radiotherapy in pediatric brainstem glioma with relation to the tumor volume

    PubMed Central

    Taran, Shachi Jain; Taran, Rakesh; Batra, Manika; Ladia, Deah Deepak; Bhandari, Virendra

    2015-01-01

    Background: Brainstem gliomas account for approximately 25% of all posterior fossa tumors. In pediatric age group, it constitutes about 10% of all brain tumors. Brainstem glioma is an aggressive and lethal type of malignancy with poor outcome despite all treatments. Aim: We studied the incidence and treatment outcome in pediatric patients with brainstem glioma depending on their tumor volume presenting in our institution in last 5 years. Brain tumors comprised 2.95% of all cancers and brainstem gliomas were 8% of all brain tumors. Materials and Methods: Nine pediatric patients were included in this analysis, who were treated with localized external radiotherapy 54–59.4 Gy along with temozolomide 75 mg/m2 during the whole course of radiotherapy. Results: The median survival in all these patients was 20 months and the overall 2 years survival is 44.4% (4/9). The median survival of patients with primary disease volume <40cc is 26 months whereas when the volume is more than 40cc the median survival is 13.5 months as calculated by Chi-square test. Conclusion: As this study includes a small number of patients with unknown histology and treated on the basis of magnetic resonance imaging findings, no definite opinion can be given as some patients may have a low-grade tumor. More studies are required to establish the relation of size of the tumor with survival. PMID:26962339

  5. Phase I Trial Using Proteasome Inhibitor Bortezomib and Concurrent Temozolomide and Radiotherapy for Central Nervous System Malignancies

    SciTech Connect

    Kubicek, Gregory J.; Werner-Wasik, Maria; Machtay, Mitchell; Mallon, Gayle; Myers, Thomas; Ramirez, Michael; Andrews, David; Curran, Walter J.; Dicker, Adam P.

    2009-06-01

    Purpose: To evaluate the toxicity and response rate of bortezomib with concurrent radiotherapy and temozolomide in the treatment of patients with central nervous system malignancies. Patients and Methods: This open-label, dose-escalation, Phase I clinical study evaluated the safety of three dose levels of intravenously administered bortezomib (0.7, 1.0, and 1.3 mg/m{sup 2}/dose) on Days 1, 4, 8, and 11 of a 21-day cycle, in addition to concurrent radiotherapy and temozolomide at a daily dose of 75 mg/m{sup 2} starting on Day 1. The primary endpoint was dose-limiting toxicity, defined as any Grade 4-5 toxicity or Grade 3 toxicity directly attributable to protocol treatment, requiring hospitalization and/or radiotherapy interruption. The secondary endpoints included feasibility, non-dose-limiting toxicity, and treatment response. Results: A total of 27 patients were enrolled, 23 of whom had high-grade glioma (10 recurrent and 13 newly diagnosed). No dose-limiting toxicities were noted in any dose group, including the highest (1.3 mg/m{sup 2}/dose). The most frequent toxicities were Grade 1 and 2 stomatitis, erythema, and alopecia. All 27 patients were evaluable for response. At a median follow-up of 15.0 months, 9 patients were still alive, with a median survival of 17.4 months for all patients and 15.0 months for patients with high-grade glioma. Conclusion: Bortezomib administered at its typical 'systemic' dose (1.3 mg/m{sup 2}) is well tolerated and safe combined with temozolomide and radiotherapy when used in the treatment of central nervous system malignancies. A Phase II study to characterize efficacy is warranted.

  6. Diffusion tensor imaging and chemical shift imaging assessment of heterogeneity in low grade glioma under temozolomide chemotherapy.

    PubMed

    Sijens, P E; Heesters, M A A M; Enting, R H; van der Graaf, W T A; Potze, J H; Irwan, R; Meiners, L C; Oudkerk, M

    2007-12-01

    Diffusion tensor imaging and multiple voxel magnetic resonance spectroscopy were performed in the MRI follow-up of a patient with a glioma treated with temozolomide chemotherapy. Tumor shrinkage was paralleled by reductions in choline level and by increases in apparent diffusion coefficient indicating decreased cellularity. Within the tumor, choline level and apparent diffusion coefficient showed a significant inverse correlation (P < 0.01). Fractional anisotropy distribution in the tumor correlated positively with N-acetyl aspartate level (P < 0.001), indicating that these parameters reflect (remaining) axonal structure. Tumor lactate level, also found to decrease under therapy, did not correlate with any other parameter.

  7. Tailored Nanoparticle Codelivery of antimiR-21 and antimiR-10b Augments Glioblastoma Cell Kill by Temozolomide: Toward a "Personalized" Anti-microRNA Therapy.

    PubMed

    Ananta, Jeyarama S; Paulmurugan, Ramasamy; Massoud, Tarik F

    2016-09-01

    Glioblastoma remains an aggressive brain malignancy with poor prognosis despite advances in multimodal therapy that include standard use of Temozolomide. MicroRNA-21 (miR-21) and microRNA-10b (miR-10b) are oncomiRs overexpressed in glioblastoma, promoting many aspects of cancer biology. We hypothesized that PLGA nanoparticles carrying antisense miR-21 (antimiR-21) and antisense miR-10b (antimiR-10b) might beneficially knockdown endogenous miR-21 and miR-10b function and reprogram cells prior to Temozolomide treatment. PLGA nanoparticles were effective in intracellular delivery of encapsulated oligonucleotides. Concentrations of delivered antimiR-21 and antimiR-10b were optimized and specifically tailored to copy numbers of intracellular endogenous microRNAs. Coinhibition of miR-21 and miR-10b significantly reduced the number of viable cells (by 24%; p < 0.01) and increased (2.9-fold) cell cycle arrest at G2/M phase upon Temozolomide treatment in U87 MG cells. Cell-tailored nanoparticle-assisted concurrent silencing of miR-21 and miR-10b prior to Temozolomide treatment is an effective molecular therapeutic strategy in cell culture, warranting the need for further studies prior to future in vivo "personalized" medicine applications.

  8. SRPX2 Enhances the Epithelial-Mesenchymal Transition and Temozolomide Resistance in Glioblastoma Cells.

    PubMed

    Tang, Haitao; Zhao, Jiaxin; Zhang, Liangyu; Zhao, Jiang; Zhuang, Yongzhi; Liang, Peng

    2016-10-01

    Glioblastoma (GBM) is the most common and most aggressive central nervous system tumor in adults. Due to GBM cell invasiveness and resistance to chemotherapy, current medical interventions are not satisfactory, and the prognosis for GBM is poor. It is necessary to investigate the underlying mechanism of GBM metastasis and drug resistance so that more effective treatments can be developed for GBM patients. sushi repeat-containing protein, X-linked 2 (SRPX2) is a prognostic biomarker in many different cancer cell lines and is associated with poor prognosis in cancer patients. SRPX2 overexpression promotes interactions between tumor and endothelial cells, leading to tumor progression and metastasis. We hypothesize that SRPX2 also contributes to GBM chemotherapy resistance and metastasis. Our results revealed that GBM tumor samples from 42 patients expressed higher levels of SRPX2 than the control normal brain tissue samples. High-SRPX2 expression levels are correlated with poor prognosis in those patients, as well as resistance to temozolomide in cultured GBM cells. Up-regulating SRPX2 expression in cultured GBM cell lines facilitated invasiveness and migration of GBM cells, while down-regulating SRPX2 through RNA interference was inhibitory. These results suggest that SRPX2 plays an important role in GBM metastasis. Epithelial to mesenchymal transition (EMT) is one of the processes that facilitate GBM metastasis and resistance to chemotherapy. EMT marker expression was decreased in SRPX2 down-regulated GBM cells, and MAPK signaling pathway marker expression was also decreased when SRPX2 is knocked down in GBM-cultured cells. Blocking the MAPK signaling pathway inhibited GBM metastasis but did not inhibit cell invasion and migration in SRPX2 down-regulated cells. Our results indicate that SRPX2 facilitates GBM metastasis by enhancing the EMT process via the MAPK signaling pathway. PMID:26643178

  9. SRPX2 Enhances the Epithelial-Mesenchymal Transition and Temozolomide Resistance in Glioblastoma Cells.

    PubMed

    Tang, Haitao; Zhao, Jiaxin; Zhang, Liangyu; Zhao, Jiang; Zhuang, Yongzhi; Liang, Peng

    2016-10-01

    Glioblastoma (GBM) is the most common and most aggressive central nervous system tumor in adults. Due to GBM cell invasiveness and resistance to chemotherapy, current medical interventions are not satisfactory, and the prognosis for GBM is poor. It is necessary to investigate the underlying mechanism of GBM metastasis and drug resistance so that more effective treatments can be developed for GBM patients. sushi repeat-containing protein, X-linked 2 (SRPX2) is a prognostic biomarker in many different cancer cell lines and is associated with poor prognosis in cancer patients. SRPX2 overexpression promotes interactions between tumor and endothelial cells, leading to tumor progression and metastasis. We hypothesize that SRPX2 also contributes to GBM chemotherapy resistance and metastasis. Our results revealed that GBM tumor samples from 42 patients expressed higher levels of SRPX2 than the control normal brain tissue samples. High-SRPX2 expression levels are correlated with poor prognosis in those patients, as well as resistance to temozolomide in cultured GBM cells. Up-regulating SRPX2 expression in cultured GBM cell lines facilitated invasiveness and migration of GBM cells, while down-regulating SRPX2 through RNA interference was inhibitory. These results suggest that SRPX2 plays an important role in GBM metastasis. Epithelial to mesenchymal transition (EMT) is one of the processes that facilitate GBM metastasis and resistance to chemotherapy. EMT marker expression was decreased in SRPX2 down-regulated GBM cells, and MAPK signaling pathway marker expression was also decreased when SRPX2 is knocked down in GBM-cultured cells. Blocking the MAPK signaling pathway inhibited GBM metastasis but did not inhibit cell invasion and migration in SRPX2 down-regulated cells. Our results indicate that SRPX2 facilitates GBM metastasis by enhancing the EMT process via the MAPK signaling pathway.

  10. A stapled peptide antagonist of MDM2 carried by polymeric micelles sensitizes glioblastoma to temozolomide treatment through p53 activation.

    PubMed

    Chen, Xishan; Tai, Lingyu; Gao, Jie; Qian, Jianchang; Zhang, Mingfei; Li, Beibei; Xie, Cao; Lu, Linwei; Lu, Wuyuan; Lu, Weiyue

    2015-11-28

    Antagonizing MDM2 and MDMX to activate the tumor suppressor protein p53 is an attractive therapeutic paradigm for the treatment of glioblastoma multiforme (GBM). However, challenges remain with respect to the poor ability of p53 activators to efficiently cross the blood-brain barrier and/or blood-brain tumor barrier and to specifically target tumor cells. To circumvent these problems, we developed a cyclic RGD peptide-conjugated poly(ethylene glycol)-co-poly(lactic acid) polymeric micelle (RGD-M) that carried a stapled peptide antagonist of both MDM2 and MDMX (sPMI). The peptide-carrying micelle RGD-M/sPMI was prepared via film-hydration method with high encapsulation efficiency and loading capacity as well as ideal size distribution. Micelle encapsulation dramatically increased the solubility of sPMI, thus alleviating its serum sequestration. In vitro studies showed that RGD-M/sPMI efficiently inhibited the proliferation of glioma cells in the presence of serum by activating the p53 signaling pathway. Further, RGD-M/sPMI exerted potent tumor growth inhibitory activity against human glioblastoma in nude mouse xenograft models. Importantly, the combination of RGD-M/sPMI and temozolomide--a standard chemotherapy drug for GBM increased antitumor efficacy against glioblastoma in experimental animals. Our results validate a combination therapy using p53 activators with temozolomide as a more effective treatment for GBM. PMID:26428461

  11. mTOR inhibition decreases SOX2-SOX9 mediated glioma stem cell activity and temozolomide resistance

    PubMed Central

    Garros-Regulez, Laura; Aldaz, Paula; Arrizabalaga, Olatz; Moncho-Amor, Veronica; Carrasco-Garcia, Estefania; Manterola, Lorea; Moreno-Cugnon, Leire; Barrena, Cristina; Villanua, Jorge; Ruiz, Irune; Pollard, Steven; Lovell-Badge, Robin; Sampron, Nicolas; Garcia, Idoia; Matheu, Ander

    2016-01-01

    ABSTRACT Background: SOX2 and SOX9 are commonly overexpressed in glioblastoma, and regulate the activity of glioma stem cells (GSCs). Their specific and overlapping roles in GSCs and glioma treatment remain unclear. Methods: SOX2 and SOX9 levels were examined in human biopsies. Gain and loss of function determined the impact of altering SOX2 and SOX9 on cell proliferation, senescence, stem cell activity, tumorigenesis and chemoresistance. Results: SOX2 and SOX9 expression correlates positively in glioma cells and glioblastoma biopsies. High levels of SOX2 bypass cellular senescence and promote resistance to temozolomide. Mechanistic investigations revealed that SOX2 acts upstream of SOX9. mTOR genetic and pharmacologic (rapamycin) inhibition decreased SOX2 and SOX9 expression, and reversed chemoresistance. Conclusions: Our findings reveal SOX2-SOX9 as an oncogenic axis that regulates stem cell properties and chemoresistance. We identify that rapamycin abrogate SOX protein expression and provide evidence that a combination of rapamycin and temozolomide inhibits tumor growth in cells with high SOX2/SOX9. PMID:26878385

  12. Quantum chemical calculations and analysis of FTIR, FT-Raman and UV-Vis spectra of temozolomide molecule

    NASA Astrophysics Data System (ADS)

    Bhat, Sheeraz Ahmad; Ahmad, Shabbir

    2015-11-01

    A combined experimental and theoretical study of the structure, vibrational and electronic spectra of temozolomide molecule, which is largely used in the treatment of brain tumours, is presented. FTIR (4000-400 cm-1) and FT-Raman spectra (4000‒50 cm-1) have been recorded and analysed using anharmonic frequency calculations using VPT2, VSCF and CC-VSCF levels of theory within B3LYP/6-311++G(d,p) framework. Anharmonic methods give accurate frequencies of fundamental modes, overtones as well as Fermi resonances and account for coupling of different modes. The anharmonic frequencies calculated using VPT2 and CC-VSCF methods show better agreement with the experimental data. Harmonic frequencies including solvent effects are also computed using IEF-PCM model. The magnitudes of coupling between pair of modes have been calculated using coupling integral based on 2MR-QFF approximation. Intermolecular interactions are discussed for three possible dimers of temozolomide. UV-Vis spectrum, examined in ethanol solvent, is compared with the calculated spectrum at TD-DFT/6-311++G(d,p) level of theory. The electronic properties, such as excitation energy, frontier molecular orbital energies and the assignments of the absorption bands are also discussed.

  13. Temozolomide downregulates P-glycoprotein expression in glioblastoma stem cells by interfering with the Wnt3a/glycogen synthase-3 kinase/β-catenin pathway

    PubMed Central

    Riganti, Chiara; Salaroglio, Iris Chiara; Caldera, Valentina; Campia, Ivana; Kopecka, Joanna; Mellai, Marta; Annovazzi, Laura; Bosia, Amalia; Ghigo, Dario; Schiffer, Davide

    2013-01-01

    Background Glioblastoma multiforme stem cells display a highly chemoresistant phenotype, whose molecular basis is poorly known. We aim to clarify this issue and to investigate the effects of temozolomide on chemoresistant stem cells. Methods A panel of human glioblastoma cultures, grown as stem cells (neurospheres) and adherent cells, was used. Results Neurospheres had a multidrug resistant phenotype compared with adherent cells. Such chemoresistance was overcome by apparently noncytotoxic doses of temozolomide, which chemosensitized glioblastoma cells to doxorubicin, vinblastine, and etoposide. This effect was selective for P-glycoprotein (Pgp) substrates and for stem cells, leading to an investigation of whether there was a correlation between the expression of Pgp and the activity of typical stemness pathways. We found that Wnt3a and ABCB1, which encodes for Pgp, were both highly expressed in glioblastoma stem cells and reduced by temozolomide. Temozolomide-treated cells had increased methylation of the cytosine–phosphate–guanine islands in the Wnt3a gene promoter, decreased expression of Wnt3a, disrupted glycogen synthase-3 kinase/β-catenin axis, reduced transcriptional activation of ABCB1, and a lower amount and activity of Pgp. Wnt3a overexpression was sufficient to transform adherent cells into neurospheres and to simultaneously increase proliferation and ABCB1 expression. On the contrary, glioblastoma stem cells silenced for Wnt3a lost the ability to form neurospheres and reduced at the same time the proliferation rate and ABCB1 levels. Conclusions Our work suggests that Wnt3a is an autocrine mediator of stemness, proliferation, and chemoresistance in human glioblastoma and that temozolomide may chemosensitize the stem cell population by downregulating Wnt3a signaling. PMID:23897632

  14. RTOG 0913: A Phase 1 Study of Daily Everolimus (RAD001) in Combination With Radiation Therapy and Temozolomide in Patients With Newly Diagnosed Glioblastoma

    SciTech Connect

    Chinnaiyan, Prakash; Won, Minhee; Wen, Patrick Y.; Wendland, Merideth; Dipetrillo, Thomas A.; Corn, Benjamin W.; Mehta, Minesh P.

    2013-08-01

    Purpose: To determine the safety of the mammalian target of rapamycin inhibitor everolimus (RAD001) administered daily with concurrent radiation and temozolomide in newly diagnosed glioblastoma patients. Methods and Materials: Everolimus was administered daily with concurrent radiation (60 Gy in 30 fractions) and temozolomide (75 mg/m{sup 2} per day). Everolimus was escalated from 2.5 mg/d (dose level 1) to 5 mg/d (dose level 2) to 10 mg/d (dose level 3). Adjuvant temozolomide was delivered at 150 to 200 mg/m{sup 2} on days 1 to 5, every 28 days, for up to 12 cycles, with concurrent everolimus at the previously established daily dose of 10 mg/d. Dose escalation continued if a dose level produced dose-limiting toxicities (DLTs) in fewer than 3 of the first 6 evaluable patients. Results: Between October 28, 2010, and July 2, 2012, the Radiation Therapy Oncology Group 0913 protocol initially registered a total of 35 patients, with 25 patients successfully meeting enrollment criteria receiving the drug and evaluable for toxicity. Everolimus was successfully escalated to the predetermined maximum tolerated dose of 10 mg/d. Two of the first 6 eligible patients had a DLT at each dose level. DLTs included gait disturbance, febrile neutropenia, rash, fatigue, thrombocytopenia, hypoxia, ear pain, headache, and mucositis. Other common toxicities were grade 1 or 2 hypercholesterolemia and hypertriglyceridemia. At the time of analysis, there was 1 death reported, which was attributed to tumor progression. Conclusions: Daily oral everolimus (10 mg) combined with both concurrent radiation and temozolomide followed by adjuvant temozolomide is well tolerated, with an acceptable toxicity profile. A randomized phase 2 clinical trial with mandatory correlative biomarker analysis is currently under way, designed to both determine the efficacy of this regimen and identify molecular determinants of response.

  15. Sunscreening Agents

    PubMed Central

    Martis, Jacintha; Shobha, V; Sham Shinde, Rutuja; Bangera, Sudhakar; Krishnankutty, Binny; Bellary, Shantala; Varughese, Sunoj; Rao, Prabhakar; Naveen Kumar, B.R.

    2013-01-01

    The increasing incidence of skin cancers and photodamaging effects caused by ultraviolet radiation has increased the use of sunscreening agents, which have shown beneficial effects in reducing the symptoms and reoccurrence of these problems. Many sunscreen compounds are in use, but their safety and efficacy are still in question. Efficacy is measured through indices, such as sun protection factor, persistent pigment darkening protection factor, and COLIPA guidelines. The United States Food and Drug Administration and European Union have incorporated changes in their guidelines to help consumers select products based on their sun protection factor and protection against ultraviolet radiation, whereas the Indian regulatory agency has not yet issued any special guidance on sunscreening agents, as they are classified under cosmetics. In this article, the authors discuss the pharmacological actions of sunscreening agents as well as the available formulations, their benefits, possible health hazards, safety, challenges, and proper application technique. New technologies and scope for the development of sunscreening agents are also discussed as well as the role of the physician in patient education about the use of these agents. PMID:23320122

  16. Antiparasitic agents.

    PubMed

    Rosenblatt, J E

    1992-03-01

    In recent years, introduction of new and more effective agents has improved the overall therapy for parasitic infections. This field, however, is still plagued by numerous problems, including the development of resistance to antimicrobial agents (especially with malaria), unavailability of agents in the United States or lack of approval by the Food and Drug Administration, and major toxicities or lack of experience in pregnant women and children, which limits use in these groups of patients. Widespread resistance of Plasmodium falciparum to chloroquine and other agents has complicated the treatment and prophylaxis of this type of malaria. A combination of quinine and Fansidar is usually effective oral therapy for falciparum malaria; quinidine may be administered if intravenous therapy is needed. Mefloquine, which is currently recommended for prophylaxis against chloroquine-resistant P. falciparum, is also effective for single-dose oral treatment, although this regimen has not yet been approved by the Food and Drug Administration. Metronidazole has been widely used for treatment of gastroenteritis due to Entamoeba histolytica and Giardia lamblia (not approved by the Food and Drug Administration for the latter) and is considered safe and effective. A new macrolide, azithromycin, has been reported to be effective for cryptosporidiosis in experimental animals; currently, no effective therapy is available for human infections. Combinations of sulfonamides with other antifolates, trimethoprim or pyrimethamine, are recommended therapy for Pneumocystis carinii pneumonia or toxoplasmosis, respectively. Therapies for the various types of leishmaniasis and trypanosomiasis are complex, often toxic, and often of limited efficacy. The benzimidazoles are effective for roundworm infections, although thiabendazole has severe toxic effects. The recent introduction of ivermectin has revolutionized the treatment and control of onchocerciasis. Another relatively new agent, praziquantel

  17. Antidiabetic Agents.

    ERIC Educational Resources Information Center

    Plummer, Nancy; Michael, Nancy, Ed.

    This module on antidiabetic agents is intended for use in inservice or continuing education programs for persons who administer medications in long-term care facilities. Instructor information, including teaching suggestions, and a listing of recommended audiovisual materials and their sources appear first. The module goal and objectives are then…

  18. Specific Inhibition of DNMT3A/ISGF3γ Interaction Increases the Temozolomide Efficiency to Reduce Tumor Growth

    PubMed Central

    Cheray, Mathilde; Pacaud, Romain; Nadaradjane, Arulraj; Oliver, Lisa; Vallette, François M; Cartron, Pierre-François

    2016-01-01

    DNA methylation is a fundamental feature of genomes and is a candidate for pharmacological manipulation that might have important therapeutic advantage. Thus, DNA methyltransferases (DNMTs) appear to be ideal targets for drug intervention. By focusing on interactions existing between DNMT3A and DNMT3A-binding protein (D3A-BP), our work identifies the DNMT3A/ISGF3γ interaction such as a biomarker whose the presence level is associated with a poor survival prognosis and with a poor prognosis of response to the conventional chemotherapeutic treatment of glioblastoma multiforme (radiation plus temozolomide). Our data also demonstrates that the disruption of DNMT3A/ISGF3γ interactions increases the efficiency of chemotherapeutic treatment on established tumors in mice. Thus, our data opens a promising and innovative alternative to the development of specific DNMT inhibitors. PMID:27698935

  19. Specific Inhibition of DNMT3A/ISGF3γ Interaction Increases the Temozolomide Efficiency to Reduce Tumor Growth

    PubMed Central

    Cheray, Mathilde; Pacaud, Romain; Nadaradjane, Arulraj; Oliver, Lisa; Vallette, François M; Cartron, Pierre-François

    2016-01-01

    DNA methylation is a fundamental feature of genomes and is a candidate for pharmacological manipulation that might have important therapeutic advantage. Thus, DNA methyltransferases (DNMTs) appear to be ideal targets for drug intervention. By focusing on interactions existing between DNMT3A and DNMT3A-binding protein (D3A-BP), our work identifies the DNMT3A/ISGF3γ interaction such as a biomarker whose the presence level is associated with a poor survival prognosis and with a poor prognosis of response to the conventional chemotherapeutic treatment of glioblastoma multiforme (radiation plus temozolomide). Our data also demonstrates that the disruption of DNMT3A/ISGF3γ interactions increases the efficiency of chemotherapeutic treatment on established tumors in mice. Thus, our data opens a promising and innovative alternative to the development of specific DNMT inhibitors.

  20. Metronomic Doses of Temozolomide Enhance the Efficacy of Carbon Nanotube CpG Immunotherapy in an Invasive Glioma Model.

    PubMed

    Ouyang, Mao; White, Ethan E; Ren, Hui; Guo, Qin; Zhang, Ian; Gao, Hang; Yanyan, Song; Chen, Xuebo; Weng, Yiming; Da Fonseca, Anna; Shah, Sunny; Manuel, Edwin R; Zhang, Leying; Vonderfecht, Steven L; Alizadeh, Darya; Berlin, Jacob M; Badie, Behnam

    2016-01-01

    Even when treated with aggressive current therapies, most patients with glioblastoma survive less than two years. Rapid tumor growth, an invasive nature, and the blood-brain barrier, which limits the penetration of large molecules into the brain, all contribute to the poor tumor response associated with conventional therapies. Immunotherapy has emerged as a therapeutic approach that may overcome these challenges. We recently reported that single-walled carbon nanotubes (SWCNTs) can be used to dramatically increase the immunotherapeutic efficacy of CpG oligonucleotides in a mouse model of glioma. Following implantation in the mouse brain, the tumor cell line used in these previous studies (GL261) tends to form a spherical tumor with limited invasion into healthy brain. In order to evaluate SWCNT/CpG therapy under more clinically-relevant conditions, here we report the treatment of a more invasive mouse glioma model (K-Luc) that better recapitulates human disease. In addition, a CpG sequence previously tested in humans was used to formulate the SWCNT/CpG which was combined with temozolomide, the standard of care chemotherapy for glioblastoma patients. We found that, following two intracranial administrations, SWCNT/CpG is well-tolerated and improves the survival of mice bearing invasive gliomas. Interestingly, the efficacy of SWCNT/CpG was enhanced when combined with temozolomide. This enhanced anti-tumor efficacy was correlated to an increase of tumor-specific cytotoxic activity in splenocytes. These results reinforce the emerging understanding that immunotherapy can be enhanced by combining it with chemotherapy and support the continued development of SWCNT/CpG. PMID:26829221

  1. Metronomic Doses of Temozolomide Enhance the Efficacy of Carbon Nanotube CpG Immunotherapy in an Invasive Glioma Model

    PubMed Central

    Guo, Qin; Zhang, Ian; Gao, Hang; Yanyan, Song; Chen, Xuebo; Weng, Yiming; Da Fonseca, Anna; Shah, Sunny; Manuel, Edwin R.; Zhang, Leying; Vonderfecht, Steven L.; Alizadeh, Darya; Berlin, Jacob M.; Badie, Behnam

    2016-01-01

    Even when treated with aggressive current therapies, most patients with glioblastoma survive less than two years. Rapid tumor growth, an invasive nature, and the blood-brain barrier, which limits the penetration of large molecules into the brain, all contribute to the poor tumor response associated with conventional therapies. Immunotherapy has emerged as a therapeutic approach that may overcome these challenges. We recently reported that single-walled carbon nanotubes (SWCNTs) can be used to dramatically increase the immunotherapeutic efficacy of CpG oligonucleotides in a mouse model of glioma. Following implantation in the mouse brain, the tumor cell line used in these previous studies (GL261) tends to form a spherical tumor with limited invasion into healthy brain. In order to evaluate SWCNT/CpG therapy under more clinically-relevant conditions, here we report the treatment of a more invasive mouse glioma model (K-Luc) that better recapitulates human disease. In addition, a CpG sequence previously tested in humans was used to formulate the SWCNT/CpG which was combined with temozolomide, the standard of care chemotherapy for glioblastoma patients. We found that, following two intracranial administrations, SWCNT/CpG is well-tolerated and improves the survival of mice bearing invasive gliomas. Interestingly, the efficacy of SWCNT/CpG was enhanced when combined with temozolomide. This enhanced anti-tumor efficacy was correlated to an increase of tumor-specific cytotoxic activity in splenocytes. These results reinforce the emerging understanding that immunotherapy can be enhanced by combining it with chemotherapy and support the continued development of SWCNT/CpG. PMID:26829221

  2. Combinations of PARP Inhibitors with Temozolomide Drive PARP1 Trapping and Apoptosis in Ewing’s Sarcoma

    PubMed Central

    Pshenichnaya, Irina; Kogera, Fiona A.; Barthorpe, Syd; Mironenko, Tatiana; Richardson, Laura; Benes, Cyril H.; Stratton, Michael R.; McDermott, Ultan; Jackson, Stephen P.; Garnett, Mathew J.

    2015-01-01

    Ewing’s sarcoma is a malignant pediatric bone tumor with a poor prognosis for patients with metastatic or recurrent disease. Ewing’s sarcoma cells are acutely hypersensitive to poly (ADP-ribose) polymerase (PARP) inhibition and this is being evaluated in clinical trials, although the mechanism of hypersensitivity has not been directly addressed. PARP inhibitors have efficacy in tumors with BRCA1/2 mutations, which confer deficiency in DNA double-strand break (DSB) repair by homologous recombination (HR). This drives dependence on PARP1/2 due to their function in DNA single-strand break (SSB) repair. PARP inhibitors are also cytotoxic through inhibiting PARP1/2 auto-PARylation, blocking PARP1/2 release from substrate DNA. Here, we show that PARP inhibitor sensitivity in Ewing’s sarcoma cells is not through an apparent defect in DNA repair by HR, but through hypersensitivity to trapped PARP1-DNA complexes. This drives accumulation of DNA damage during replication, ultimately leading to apoptosis. We also show that the activity of PARP inhibitors is potentiated by temozolomide in Ewing’s sarcoma cells and is associated with enhanced trapping of PARP1-DNA complexes. Furthermore, through mining of large-scale drug sensitivity datasets, we identify a subset of glioma, neuroblastoma and melanoma cell lines as hypersensitive to the combination of temozolomide and PARP inhibition, potentially identifying new avenues for therapeutic intervention. These data provide insights into the anti-cancer activity of PARP inhibitors with implications for the design of treatment for Ewing’s sarcoma patients with PARP inhibitors. PMID:26505995

  3. Silencing of Hsp27 and Hsp72 in glioma cells as a tool for programmed cell death induction upon temozolomide and quercetin treatment

    SciTech Connect

    Jakubowicz-Gil, Joanna; Langner, Ewa; Bądziul, Dorota; Wertel, Iwona; Rzeski, Wojciech

    2013-12-15

    The aim of the present study was to investigate whether silencing of Hsp27 or Hsp72 expression in glioblastoma multiforme T98G and anaplastic astrocytoma MOGGCCM cells increases their sensitivity to programmed cell death induction upon temozolomide and/or quercetin treatment. Transfection with specific siRNA was performed for the Hsp gene silencing. As revealed by microscopic observation and flow cytometry, the inhibition of Hsp expression was correlated with severe apoptosis induction upon the drug treatment studied. No signs of autophagy were detected. This was correlated with a decreased mitochondrial membrane potential, increased level of cytochrome c in the cytoplasm, and activation of caspase 3 and caspase 9. All these results suggest that the apoptotic signal was mediated by an internal pathway. Additionally, in a large percentage of cells treated with temozolomide, with or without quercetin, granules within the ER system were found, which was accompanied by an increased level of caspase 12 expression. This might be correlated with ER stress. Quercetin and temozolomide also changed the shape of nuclei from circular to “croissant like” in both transfected cell lines. Our results indicate that blocking of Hsp27 and Hsp72 expression makes T98G cells and MOGGCCM cells extremely vulnerable to apoptosis induction upon temozolomide and quercetin treatment and that programmed cell death is initiated by an internal signal. - Highlights: • Hsps gene silencing induced severe apoptosis upon temozolomide–quercetin treatment • Apoptosis in transfected glioma cells was initiated by internal signal • Programmed cell death was preceded by ER stress • Temozolomide–quercetin treatment changed nuclei shape in transfected glioma cells.

  4. Cilengitide with metronomic temozolomide, procarbazine, and standard radiotherapy in patients with glioblastoma and unmethylated MGMT gene promoter in ExCentric, an open-label phase II trial.

    PubMed

    Khasraw, Mustafa; Lee, Adrian; McCowatt, Sally; Kerestes, Zoltan; Buyse, Marc E; Back, Michael; Kichenadasse, Ganessan; Ackland, Stephen; Wheeler, Helen

    2016-05-01

    Newly diagnosed glioblastoma multiforme with unmethylated MGMT promoter has a poor prognosis, with a median survival of 12 months. This phase II study investigated the efficacy and safety of combining the selective integrin inhibitor cilengitide with a combination of metronomic temozolomide and procarbazine for these patients. Eligible patients (newly diagnosed, histologically confirmed supratentorial glioblastoma with unmethylated MGMT promoter) were entered into this multicentre study. Cilengitide (2000 mg IV twice weekly) was commenced 1 week prior to radiotherapy combined with daily temozolomide (60 mg/m(2)) and procarbazine (50 or 100 mg) and, after 4 weeks' break, followed by six adjuvant cycles of temozolomide (50-60 mg/m(2)) and procarbazine (50 or 100 mg) on days 1-20, every 28 days. Cilengitide was continued for up to 12 months or until disease progression or unacceptable toxicity. The primary endpoint for efficacy was a 12-month overall survival rate of 65 %. Twenty-nine patients completed study treatment. Sixteen patients survived for 12 months or more, an overall survival rate of 55 %. The median overall survival was 14.5 months (95 % CI 11.1-19.6) and the median progression-free survival was 7.4 months (95 % CI 6.1-8). Cilengitide combined with metronomic temozolomide and procarbazine in MGMT-promoter unmethylated glioblastoma did not improve survival compared with historical data and does not warrant further investigation. PMID:26935578

  5. KGB agents

    NASA Astrophysics Data System (ADS)

    Gaina, Alex

    A short story is reported in which the activity of Communist Party of the USSR and secret KGB agents, which were payed by the State, in view of controlling of the conscience of population. The story reffers to the Physics Department of the Moscow University, Planing Institute of the Gosplan of Moldavian S.S.R. and Chishinau Technical University (actually: Technical University of Moldova), where the author has worked during Soviet times. Almost every 6-th citizen in the USSR was engaged in this activity, while actually the former communists rule in the Republic of Moldova.

  6. Craniospinal irradiation with concurrent temozolomide and nimotuzumab in a child with primary metastatic diffuse intrinsic pontine glioma. A compassionate use treatment.

    PubMed

    Müller, K; Schlamann, A; Seidel, C; Warmuth-Metz, M; Christiansen, H; Vordermark, D; Kortmann, R-D; Kramm, C M; von Bueren, A O

    2013-08-01

    Primary metastatic diffuse intrinsic pontine glioma (DIPG) is relatively rare and associated with a dismal prognosis. Combining craniospinal irradiation (CSI) with concurrent temozolomide and nimotuzumab therapy may slightly improve tumor control and overall survival. However, little is known about the feasibility and toxicity of this treatment approach. Here, we describe the case of an 8-year-old girl with primary metastatic DIPG who received craniospinal radiotherapy, a local boost, and concurrent temozolomide and nimotuzumab treatment based on an individual therapy recommendation. Radiotherapy could be completed without any interruption. However, concurrent temozolomide had to be disrupted several times due to considerable acute myelotoxicity (grade III-IV).Maintenance immunochemotherapy could be started with a delay of 5 days and was performed according to treatment schedule. The disease could be stabilized for a few months. A routine MRI scan finally depicted disease progression 5.7 months after the start of irradiation. The patient died 1.9 months later.

  7. The adherens junction-associated protein 1 is a negative transcriptional regulator of MAGEA2, which potentiates temozolomide-induced apoptosis in GBM.

    PubMed

    Zeng, Liang; Kang, Chunsheng; Di, Chunhui; Fee, Brian E; Rivas, Miriam; Lin, James; Adamson, David Cory

    2014-04-01

    Previous studies identified the frequent loss of adherens junction-associated protein 1 (AJAP1) expression in glioblastoma (GBM) and its correlation with worse survival. AJAP1 may suppress glioma cell migration, which plays an important role in tumor progression in malignant gliomas such as GBM. However, the role of AJAP1 in cell cycle arrest or apoptosis and resistance to chemotherapy remains unclear. Based on microarray screening results, quantitative PCR and luciferase plasmid reporter constructs were used to evaluate the possible regulatory role of AJAP1 on MAGEA2 expression and function. Cell death assays, TUNEL and other markers of apoptosis were utilized to detect cell apoptosis. Restoration of AJAP1 expression in glioma cells was analyzed after temozolomide exposure. AJAP1 suppressed the expression of MAGEA2 and inhibited the transcriptional activity of MAGEA2 in glioma cells. As AJAP1 expression decreased MAGEA2 protein expression apoptosis increased moderately. Consistent with increased cell death, the induced loss of MAGEA2 expression correlated with increased caspase 3/7 activity, BCL2/BAX ratio and TUNEL signal. AJAP1 expression enhanced cell death in the presence of temozolomide. This study suggests AJAP1 may also function as a pro-apoptotic factor and potentiate cell death by temozolomide in glioma cells. This effect may be partially explained by AJAP1-mediated gene regulation of MAGEA2. PMID:24481586

  8. Filling agents.

    PubMed

    Glavas, Ioannis P

    2005-06-01

    Injectable fillers have become an important component of minimally invasive facial rejuvenation modalities. Their ease of use, effectiveness, low morbidity, and fast results with minimal downtime are factors that have made them popular among patients. Soft tissue augmentation has evolved to a unique combination of medicine and art. A wide selection of available agents and new products, each one with unique properties, may be used alone or in combination. The physician acquires the tools to rebalance facial characteristics not only by filling wrinkles but also by having the ability to shape the face and restore bony contours and lines. Careful selection of candidates, realistic expectations, and an understanding of the limitations of fillers are crucial for a successful result.

  9. Health care agents

    MedlinePlus

    Durable power of attorney for health care; Health care proxy; End-of-life - health care agent; Life support treatment - ... Respirator - health care agent; Ventilator - health care agent; Power of attorney - health care agent; POA - health care ...

  10. Survival following reirradiation using intensity-modulated radiation therapy with temozolomide in selected patients with recurrent high grade gliomas

    PubMed Central

    Koc, Mehmet; Kanyilmaz, Gul

    2015-01-01

    Background High grade gliomas often recur after initial treatment. Despite so many treatment options, there is no standard treatment for recurrent gliomas. The aim of this study is to offer survival following reirradiation (re-RT) using intensity-modulated radiation therapy (IMRT) with temozolomide in selected patients with recurrent high grade gliomas. Methods We examined the medical records of 21 adult patients with recurrent high grade gliomas who were reirradiated with IMRT at the time of tumor recurrence or progression. Tumor recurrence was shown by gadolinium-enhanced magnetic resonance imaging (MRI) and diagnosis was established by pathology review. Statistical analyses were performed with SPSS version 18.0.1 using Cox regression analyses, log-rank test and Kaplan-Meier method. Results Eighteen patients presented by localized recurrence, three patients with diffuse recurrence. Median radiotherapy (RT) dose was 54 Gy. About 81% patients received temozolomide with re-RT. The time interval between two courses RT was median 39.3 months (range, 9.6-140.8 months). The response was checked by MRI. About 24% patients achieved complete response (CR) and 29% patient partial response (PR). Stable disease (SD) was observed in 47% patients. Median follow-up time from diagnosis was 41.4 months (range, 16.6-145.4 months) and 12.3 months (range, 2-27.6 months) from re-RT. Median time to recurrence was 39.3 months (range, 9.6-140.8 months). Median survival after re-RT was 18 months for anaplastic astrocytoma (AA), 14.1 months for glioblastoma multiforme (GBM) (range, 11-17.2 months) (P=0.1) and 7.1 months for patients with Karnofsky performance status (KPS) <70 before re-RT and 17.4 months for KPS >70 (P=0.02). Conclusions re-RT is one of the treatment options for recurrent high grade gliomas and IMRT can be an effective treatment modality for recurrent high grade brain tumors with only mild side effects. Survival is better in patients with good performance status and in

  11. Detecting agents.

    PubMed Central

    Johnson, Susan C

    2003-01-01

    This paper reviews a recent set of behavioural studies that examine the scope and nature of the representational system underlying theory-of-mind development. Studies with typically developing infants, adults and children with autism all converge on the claim that there is a specialized input system that uses not only morphological cues, but also behavioural cues to categorize novel objects as agents. Evidence is reviewed in which 12- to 15-month-old infants treat certain non-human objects as if they have perceptual/attentional abilities, communicative abilities and goal-directed behaviour. They will follow the attentional orientation of an amorphously shaped novel object if it interacts contingently with them or with another person. They also seem to use a novel object's environmentally directed behaviour to determine its perceptual/attentional orientation and object-oriented goals. Results from adults and children with autism are strikingly similar, despite adults' contradictory beliefs about the objects in question and the failure of children with autism to ultimately develop more advanced theory-of-mind reasoning. The implications for a general theory-of-mind development are discussed. PMID:12689380

  12. State of the art and perspectives in the treatment of glioblastoma.

    PubMed

    Grimm, Sean A; Chamberlain, Marc C

    2012-09-01

    Glioblastoma is the most common malignant primary brain tumor. Cures are rare and median survival varies from several to 22 months. Standard treatment for good performance patients consists of maximal safe surgical resection followed by radiotherapy with concurrent temozolomide (TMZ) chemotherapy and six cycles of postradiotherapy TMZ. At recurrence, treatment options include repeat surgery (with or without Gliadel wafer placement), reirradiation or systemic therapy. Most patients with good performance status are treated with cytotoxic chemotherapy or targeted biologic therapy following or in lieu of repeat surgery. Cytotoxic chemotherapy options include nitrosoureas, rechallenge with TMZ, platins, phophoramides and topoisomerase inhibitors, although efficacy is limited. Despite the intense effort of developing biologic agents that target angiogenesis and growth and proliferative pathways, bevacizumab is the only agent that has shown efficacy in clinical trials. It was awarded accelerated approval in the USA after demonstrating an impressive radiographic response in two open-label, prospective Phase II studies. Two randomized, Phase III trials of upfront bevacizumab have completed and may demonstrate survival benefit; however, results are pending at this time. Given the limited treatment options at tumor recurrence, consideration for enrollment on a clinical trial is encouraged.

  13. State of the art and perspectives in the treatment of glioblastoma.

    PubMed

    Grimm, Sean A; Chamberlain, Marc C

    2012-09-01

    Glioblastoma is the most common malignant primary brain tumor. Cures are rare and median survival varies from several to 22 months. Standard treatment for good performance patients consists of maximal safe surgical resection followed by radiotherapy with concurrent temozolomide (TMZ) chemotherapy and six cycles of postradiotherapy TMZ. At recurrence, treatment options include repeat surgery (with or without Gliadel wafer placement), reirradiation or systemic therapy. Most patients with good performance status are treated with cytotoxic chemotherapy or targeted biologic therapy following or in lieu of repeat surgery. Cytotoxic chemotherapy options include nitrosoureas, rechallenge with TMZ, platins, phophoramides and topoisomerase inhibitors, although efficacy is limited. Despite the intense effort of developing biologic agents that target angiogenesis and growth and proliferative pathways, bevacizumab is the only agent that has shown efficacy in clinical trials. It was awarded accelerated approval in the USA after demonstrating an impressive radiographic response in two open-label, prospective Phase II studies. Two randomized, Phase III trials of upfront bevacizumab have completed and may demonstrate survival benefit; however, results are pending at this time. Given the limited treatment options at tumor recurrence, consideration for enrollment on a clinical trial is encouraged. PMID:25054300

  14. Phase II trial of hypofractionated intensity-modulated radiation therapy combined with temozolomide and bevacizumab for patients with newly diagnosed glioblastoma.

    PubMed

    Ney, Douglas E; Carlson, Julie A; Damek, Denise M; Gaspar, Laurie E; Kavanagh, Brian D; Kleinschmidt-DeMasters, B K; Waziri, Allen E; Lillehei, Kevin O; Reddy, Krishna; Chen, Changhu

    2015-03-01

    Bevacizumab blocks the effects of VEGF and may allow for more aggressive radiotherapy schedules. We evaluated the efficacy and toxicity of hypofractionated intensity-modulated radiation therapy with concurrent and adjuvant temozolomide and bevacizumab in patients with newly diagnosed glioblastoma. Patients with newly diagnosed glioblastoma were treated with hypofractionated intensity modulated radiation therapy to the surgical cavity and residual tumor with a 1 cm margin (PTV1) to 60 Gy and to the T2 abnormality with a 1 cm margin (PTV2) to 30 Gy in 10 daily fractions over 2 weeks. Concurrent temozolomide (75 mg/m(2) daily) and bevacizumab (10 mg/kg) was administered followed by adjuvant temozolomide (200 mg/m(2)) on a standard 5/28 day cycle and bevacizumab (10 mg/kg) every 2 weeks for 6 months. Thirty newly diagnosed patients were treated on study. Median PTV1 volume was 131.1 cm(3) and the median PTV2 volume was 342.6 cm(3). Six-month progression-free survival (PFS) was 90 %, with median follow-up of 15.9 months. The median PFS was 14.3 months, with a median overall survival (OS) of 16.3 months. Grade 4 hematologic toxicity included neutropenia (10 %) and thrombocytopenia (17 %). Grades 3/4 non-hematologic toxicity included fatigue (13 %), wound dehiscence (7 %) and stroke, pulmonary embolism and nausea each in 1 patient. Presumed radiation necrosis with clinical decline was seen in 50 % of patients, two with autopsy documentation. The study was closed early to accrual due to this finding. This study demonstrated 90 % 6-month PFS and OS comparable to historic data in patients receiving standard treatment. Bevacizumab did not prevent radiation necrosis associated with this hypofractionated radiation regimen and large PTV volumes may have contributed to high rates of presumed radiation necrosis. PMID:25524817

  15. Phase II Study of Erlotinib Plus Temozolomide During and After Radiation Therapy in Patients With Newly Diagnosed Glioblastoma Multiforme or Gliosarcoma

    PubMed Central

    Prados, Michael D.; Chang, Susan M.; Butowski, Nicholas; DeBoer, Rebecca; Parvataneni, Rupa; Carliner, Hannah; Kabuubi, Paul; Ayers-Ringler, Jennifer; Rabbitt, Jane; Page, Margaretta; Fedoroff, Anne; Sneed, Penny K.; Berger, Mitchel S.; McDermott, Michael W.; Parsa, Andrew T.; Vandenberg, Scott; James, C. David; Lamborn, Kathleen R.; Stokoe, David; Haas-Kogan, Daphne A.

    2009-01-01

    Purpose This open-label, prospective, single-arm, phase II study combined erlotinib with radiation therapy (XRT) and temozolomide to treat glioblastoma multiforme (GBM) and gliosarcoma. The objectives were to determine efficacy of this treatment as measured by survival and to explore the relationship between molecular markers and treatment response. Patients and Methods Sixty-five eligible adults with newly diagnosed GBM or gliosarcoma were enrolled. We intended to treat patients not currently treated with enzyme-inducing antiepileptic drugs (EIAEDs) with 100 mg/d of erlotinib during XRT and 150 mg/d after XRT. Patients receiving EIAEDs were to receive 200 mg/d of erlotinib during XRT and 300 mg/d after XRT. After XRT, the erlotinib dose was escalated until patients developed tolerable grade 2 rash or until the maximum allowed dose was reached. All patients received temozolomide during and after XRT. Molecular markers of epidermal growth factor receptor (EGFR), EGFRvIII, phosphatase and tensin homolog (PTEN), and methylation status of the promotor region of the MGMT gene were analyzed from tumor tissue. Survival was compared with outcomes from two historical phase II trials. Results Median survival was 19.3 months in the current study and 14.1 months in the combined historical control studies, with a hazard ratio for survival (treated/control) of 0.64 (95% CI, 0.45 to 0.91). Treatment was well tolerated. There was a strong positive correlation between MGMT promotor methylation and survival, as well as an association between MGMT promotor-methylated tumors and PTEN positivity shown by immunohistochemistry with improved survival. Conclusion Patients treated with the combination of erlotinib and temozolomide during and following radiotherapy had better survival than historical controls. Additional studies are warranted. PMID:19075262

  16. Preparing Change Agents for Change Agent Roles.

    ERIC Educational Resources Information Center

    Sedlacek, James R.

    Seventy-seven Spanish- and Portuguese-speaking agricultural change agents from developing Central and South American countries responded to a questionnaire which sought perceptions of the roles in which the change agents felt they were involved and the roles for which they felt they were being trained. The agents were participating in training…

  17. Remote Agent Demonstration

    NASA Technical Reports Server (NTRS)

    Dorais, Gregory A.; Kurien, James; Rajan, Kanna

    1999-01-01

    We describe the computer demonstration of the Remote Agent Experiment (RAX). The Remote Agent is a high-level, model-based, autonomous control agent being validated on the NASA Deep Space 1 spacecraft.

  18. β-elemene enhances both radiosensitivity and chemosensitivity of glioblastoma cells through the inhibition of the ATM signaling pathway.

    PubMed

    Liu, Siwei; Zhou, Lei; Zhao, Yongshun; Yuan, Yuhui

    2015-08-01

    Glioblastoma multiforme (GBM), a tumor associated with poor prognosis, is known to be resistant to radiotherapy and alkylating agents such as temozolomide (TMZ). β-elemene, a monomer found in Chinese traditional herbs extracted from Curcuma wenyujin, is currently being used as an antitumor drug for different types of tumors including GBM. In the present study, we investigated the roles of β-elemene in the radiosensitivity and chemosensitivity of GBM cells. Human GBM cell lines U87-MG, T98G, U251, LN229 and rat C6 cells were treated with β-elemene combined with radiation or TMZ. We used MTT and colony forming assays to evaluate the proliferation and survival of the cells, and the comet assay to observe DNA damage. Expression of proteins was analyzed by immunoblotting. In the present study, we found that β-elemene inhibited the proliferation and survival of different GBM cell lines when combined with radiotherapy or TMZ via inhibition of DNA damage repair. Treatment of GBM cells with β-elemene decreased the phosphorylation of ataxia telangiectasia mutated (ATM), AKT and ERK following radiotherapy or chemotherapy. These results revealed that β-elemene could significantly increase the radiosensitivity and chemosensitivity of GBM. β-elemene may be used as a potential drug in combination with the radiotherapy and chemotherapy of GBM. PMID:26062577

  19. Boswellic acid activity against glioblastoma stem-like cells

    PubMed Central

    SCHNEIDER, HANNAH; WELLER, MICHAEL

    2016-01-01

    Boswellic acids (BAs) have long been considered as useful adjunct pharmacological agents for the treatment of patients with malignant brain tumors, notably glioblastoma. Two principal modes of action associated with BAs have been postulated: i) Anti-inflammatory properties, which are useful for containing edema formation, and ii) intrinsic antitumor cell properties, with a hitherto ill-defined mode of action. The present study assessed the effects of various BA derivatives on the viability and clonogenicity of a panel of nine long-term glioma cell lines and five glioma-initiating cell lines, studied cell cycle progression and the mode of cell death induction, and explored potential synergy with temozolomide (TMZ) or irradiation. BA induced the concentration-dependent loss of viability and clonogenicity that was independent of tumor protein 53 status and O6-methylguanine DNA methyltransferase expression. The treatment of glioma cells with BA resulted in cell death induction, prior to or upon S phase entry, and exhibited features of apoptotic cell death. Synergy with irradiation or TMZ was detected at certain concentrations; however, the inhibitory effects were mostly additive, and never antagonistic. While the intrinsic cytotoxic properties of BA at low micromolecular concentrations were confirmed and the potential synergy with irradiation and TMZ was identified, the proximate pharmacodynamic target of BA remains to be identified. PMID:27313764

  20. Biological warfare agents.

    PubMed

    Pohanka, Miroslav; Kuca, Kamil

    2010-01-01

    Biological warfare agents are a group of pathogens and toxins of biological origin that can be potentially misused for military or criminal purposes. The present review attempts to summarize necessary knowledge about biological warfare agents. The historical aspects, examples of applications of these agents such as anthrax letters, biological weapons impact, a summary of biological warfare agents and epidemiology of infections are described. The last section tries to estimate future trends in research on biological warfare agents.

  1. Spacecraft sanitation agent development

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The development of an effective sanitizing agent that is compatible with the spacecraft environment and the human occupant is discussed. Experimental results show that two sanitation agents must be used to satisfy mission requirements: one agent for personal hygiene and one for equipment maintenance. It was also recommended that a water rinse be used with the agents for best results, and that consideration be given to using the agents pressure packed or in aerosol formulations.

  2. Chemical warfare agents.

    PubMed

    Chauhan, S; Chauhan, S; D'Cruz, R; Faruqi, S; Singh, K K; Varma, S; Singh, M; Karthik, V

    2008-09-01

    Chemical warfare agents (CWA's) are defined as any chemical substance whose toxic properties are utilised to kill, injure or incapacitate an enemy in warfare and associated military operations. Chemical agents have been used in war since times immemorial, but their use reached a peak during World War I. During World War II only the Germans used them in the infamous gas chambers. Since then these have been intermittently used both in war and acts of terrorisms. Many countries have stockpiles of these agents. There has been a legislative effort worldwide to ban the use of CWA's under the chemical weapons convention which came into force in 1997. However the manufacture of these agents cannot be completely prohibited as some of them have potential industrial uses. Moreover despite the remedial measures taken so far and worldwide condemnation, the ease of manufacturing these agents and effectiveness during combat or small scale terrorist operations still make them a powerful weapon to reckon with. These agents are classified according to mechanism of toxicity in humans into blister agents, nerve agents, asphyxiants, choking agents and incapacitating/behavior altering agents. Some of these agents can be as devastating as a nuclear bomb. In addition to immediate injuries caused by chemical agents, some of them are associated with long term morbidities and psychological problems. In this review we will discuss briefly about the historical background, properties, manufacture techniques and industrial uses, mechanism of toxicity, clinical features of exposure and pharmacological management of casualties caused by chemical agents. PMID:21783898

  3. Efficacy and patient-reported outcomes with dose-intense temozolomide in patients with newly diagnosed pure and mixed anaplastic oligodendroglioma: a phase II multicenter study.

    PubMed

    Ahluwalia, Manmeet S; Xie, Hao; Dahiya, Saurabh; Hashemi-Sadraei, Nooshin; Schiff, David; Fisher, Paul G; Chamberlain, Marc C; Pannullo, Susan; Newton, Herbert B; Brewer, Cathy; Wood, Laura; Prayson, Richard; Elson, Paul; Peereboom, David M

    2015-03-01

    Standard initial therapy for patients with pure and mixed anaplastic oligodendrogliomas (AO/MAO) includes chemotherapy and radiation therapy. Anaplastic oligodendrogliomas with 1p/19q co-deletion are more responsive to chemotherapy. There is concern for potential long-term CNS toxicity of radiation. Hence an approach using chemotherapy initially and reserving radiation for progressive disease is attractive. This multicenter phase II trial included patients with newly diagnosed AO/MAO with central pathology review and 1p/19q assay. Temozolomide was given 150 mg/m(2) days 1-7 and 15-21, every 28 days for 8 cycles. The primary endpoint was progression free survival (PFS). Secondary endpoints included response rate, overall survival (OS), treatment toxicity and health-related quality of life (HRQL). Data from 62 patients enrolled between December 2001 and April 2007 at seven centers were analyzed. Among patients with measurable disease, 8 % achieved complete remission, 56 % had stable disease and 36 % had progression. The median PFS and OS were 27.2 months (95 % CI 11.9-36.3) and 105.8 months (95 % CI 51.5-N/A), respectively. Both 1p loss and 1p/19q co-deletion were positive prognostic factors for PFS (p < 0.001) and OS (p < 0.001); and there was some suggestion that 1p/19q co-deletion also predicted better response to chemotherapy (p = 0.007). Grade 3/4 toxicities were mainly hematological. Significantly improved HRQL in the future uncertainty domain of the brain cancer module was seen after cycle 4 (p < 0.001). This trial achieved outcomes similar to those reported previously. Toxicities from dose-intense temozolomide were manageable. Improvement in at least one HRQL domain increased over time. This trial supports the further study of first-line temozolomide monotherapy as an alternative to radiation therapy for patients with newly diagnosed AO/MAO with 1p 19q co-deleted tumors.

  4. Mobile Agents Applications.

    ERIC Educational Resources Information Center

    Martins, Rosane Maria; Chaves, Magali Ribeiro; Pirmez, Luci; Rust da Costa Carmo, Luiz Fernando

    2001-01-01

    Discussion of the need to filter and retrieval relevant information from the Internet focuses on the use of mobile agents, specific software components which are based on distributed artificial intelligence and integrated systems. Surveys agent technology and discusses the agent building package used to develop two applications using IBM's Aglet…

  5. Hydroxypyridonate chelating agents

    DOEpatents

    Raymond, Kenneth N.; Scarrow, Robert C.; White, David L.

    1987-01-01

    Chelating agents having 1-hydroxy-2-pyridinone (HOPO) and related moieties incorporated within their structures, including polydentate HOPO-substituted polyamines such as spermidine and spermine, and HOPO-substituted desferrioxamine. The chelating agents are useful in selectively removing certain cations from solution, and are particularly useful as ferric ion and actinide chelators. Novel syntheses of the chelating agents are provided.

  6. Prospective of curcumin, a pleiotropic signalling molecule from Curcuma longa in the treatment of Glioblastoma.

    PubMed

    Luthra, Pratibha Mehta; Lal, Neetika

    2016-02-15

    GBM (Glioblastoma) is the most malignant human brain tumor with median survival of one year. The treatment involves surgery, radiotherapy and adjuvant chemotherapy mostly with the alkylation agents such as temozolomide (TMZ). Dietary polyphenol curcumin, isolated from the rhizome of the Curcuma longa (turmeric), has emerged as remarkable anti-cancer agent in the treatment of various peripheral cancers such as blood, lymphomas, multiple myeloma, melanoma as well as skin, lung, prostate, breast, ovarian, bladder, liver, gastrointestinal tract, pancreatic and colorectal epithelial cancers with a pleiotropic mode of action and also showed promise in alleviation of GBM. In this review, the mechanism of anticancer effect of curcumin in GBM has been discussed extensively. The clinical safety and pharmacokinetics of curcumin has been scrutinized to combat the challenges for the treatment of GBM.

  7. Prospective of curcumin, a pleiotropic signalling molecule from Curcuma longa in the treatment of Glioblastoma.

    PubMed

    Luthra, Pratibha Mehta; Lal, Neetika

    2016-02-15

    GBM (Glioblastoma) is the most malignant human brain tumor with median survival of one year. The treatment involves surgery, radiotherapy and adjuvant chemotherapy mostly with the alkylation agents such as temozolomide (TMZ). Dietary polyphenol curcumin, isolated from the rhizome of the Curcuma longa (turmeric), has emerged as remarkable anti-cancer agent in the treatment of various peripheral cancers such as blood, lymphomas, multiple myeloma, melanoma as well as skin, lung, prostate, breast, ovarian, bladder, liver, gastrointestinal tract, pancreatic and colorectal epithelial cancers with a pleiotropic mode of action and also showed promise in alleviation of GBM. In this review, the mechanism of anticancer effect of curcumin in GBM has been discussed extensively. The clinical safety and pharmacokinetics of curcumin has been scrutinized to combat the challenges for the treatment of GBM. PMID:26748069

  8. Standard Agent Framework 1

    SciTech Connect

    Goldsmith, Steven Y.

    1999-04-06

    The Standard Agent framework provides an extensible object-oriented development environment suitable for use in both research and applications projects. The SAF provides a means for constructing and customizing multi-agent systems through specialization of standard base classes (architecture-driven framework) and by composition of component classes (data driven framework). The standard agent system is implemented as an extensible object-centerd framework. Four concrete base classes are developed: (1) Standard Agency; (2) Standard Agent; (3) Human Factor, and (4) Resources. The object-centered framework developed and utilized provides the best comprimise between generality and flexibility available in agent development systems today.

  9. Metronomic chemotherapy with daily low-dose temozolomide and celecoxib in elderly patients with newly diagnosed glioblastoma multiforme: a retrospective analysis.

    PubMed

    Welzel, Grit; Gehweiler, Julian; Brehmer, Stefanie; Appelt, Jens-Uwe; von Deimling, Andreas; Seiz-Rosenhagen, Marcel; Schmiedek, Peter; Wenz, Frederik; Giordano, Frank A

    2015-09-01

    Chemotherapy is often omitted in elderly patients with glioblastoma multiforme due to a fear of side effects. We applied metronomic chemotherapy with low-dose temozolomide and celecoxib (LD-TEM/CEL) during and after external beam radiotherapy (EBRT) and here report on how this regimen compares to standard temozolomide radiochemotherapy (SD-TEM) in elderly patients. We retrospectively analyzed records of 146 patients aged 65 years and older that underwent EBRT. Factors of interest were age, performance status, comorbidities, MGMT status, therapy (resection/biopsy, radiotherapy/dose, chemotherapy/regimen/dose), progression-free (PFS) and overall survival (OS) status. Irrespective of the regimen, addition of chemotherapy more than doubled median survival rates (EBRT only: 4.2 months; EBRT + LD-TEM/CEL: 8.5 months; EBRT + SD-TEM: 10.8 months; p ≤ 0.008). Although patients receiving metronomic LD-TEM/CEL were significantly older (62 % were ≥75 years vs. 22 %; p < 0.001), had significantly lower performance scores (50 % had a KPS <70 vs. 28 %; p = 0.049) and were significantly more comorbid (73 % had ≥4 comorbidities vs. 37 %; p = 0.002) than patients of the SD-TEM group, there were no significant differences in PFS and OS. Independent of other factors, omission of chemotherapy significantly impairs progression-free and overall survival. With all the limitations of a retrospective analysis, our data suggest that metronomic chemotherapy with LD-TEM/CEL may be equieffective and eventually better tolerated than SD-TEM. It may be offered to elderly patients that are not eligible for standard chemotherapy.

  10. Agent Architectures for Compliance

    NASA Astrophysics Data System (ADS)

    Burgemeestre, Brigitte; Hulstijn, Joris; Tan, Yao-Hua

    A Normative Multi-Agent System consists of autonomous agents who must comply with social norms. Different kinds of norms make different assumptions about the cognitive architecture of the agents. For example, a principle-based norm assumes that agents can reflect upon the consequences of their actions; a rule-based formulation only assumes that agents can avoid violations. In this paper we present several cognitive agent architectures for self-monitoring and compliance. We show how different assumptions about the cognitive architecture lead to different information needs when assessing compliance. The approach is validated with a case study of horizontal monitoring, an approach to corporate tax auditing recently introduced by the Dutch Customs and Tax Authority.

  11. 13 CFR 107.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Functions of agents, including... Assistance SMALL BUSINESS ADMINISTRATION SMALL BUSINESS INVESTMENT COMPANIES SBA Financial Assistance for... Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent. (a) Agents....

  12. Detecting biological warfare agents.

    PubMed

    Song, Linan; Ahn, Soohyoun; Walt, David R

    2005-10-01

    We developed a fiber-optic, microsphere-based, high-density array composed of 18 species-specific probe microsensors to identify biological warfare agents. We simultaneously identified multiple biological warfare agents in environmental samples by looking at specific probe responses after hybridization and response patterns of the multiplexed array.

  13. Travel Agent Course Outline.

    ERIC Educational Resources Information Center

    British Columbia Dept. of Education, Victoria.

    Written for college entry-level travel agent training courses, this course outline can also be used for inservice training programs offered by travel agencies. The outline provides information on the work of a travel agent and gives clear statements on what learners must be able to do by the end of their training. Material is divided into eight…

  14. Change Agent Survival Guide

    ERIC Educational Resources Information Center

    Dunbar, Folwell L.

    2011-01-01

    Consulting is a rough racket. Only a tarantula hair above IRS agents, meter maids and used car sales people, the profession is a prickly burr for slings and arrows. Throw in education, focus on dysfunctional schools and call oneself a "change agent," and this bad rap all but disappears. Unfortunately, though, consulting/coaching/mentoring in…

  15. Ferrimagnetic susceptibility contrast agents.

    PubMed

    Bach-Gansmo, T

    1993-01-01

    Contrast agents based on superparamagnetic particles have been in clinical development for more than 5 years, and the complexity of their effects is still not elucidated. The relaxivities are frequently used to give an idea of their efficacy, but these parameters can only be used if they are concentration independent. For large superparamagnetic systems, the evolution of the transverse magnetization is biexponential, after an initial loss of magnetization. Both these characteristics of large superparamagnetic systems should lead to prudence in using the relaxivities as indicators of contrast medium efficacy. Susceptibility induced artefacts have been associated with the use of superparamagnetic contrast agents since the first imaging evaluation took place. The range of concentrations where good contrast effect was achieved without inducing artefacts, as well as blurring and metal artefacts were evaluated. The influence of motion on the induction of artefacts was studied, and compared to the artefacts induced by a paramagnetic agent subject to motion. With a suitable concentration of a negative contrast agent, a signal void could be achieved in the region prone to motion, and no artefacts were induced. If the concentration was too high, a displacement of the region close to the contrast agent was observed. The artefacts occurred in a volume surrounding the contrast agent, i.e., also outside the imaging plane. In comparison a positive, paramagnetic contrast agent induced heavy artefacts in the phase encoding direction, appearing as both high intensity regions and black holes, in a mosaic pattern. Clinical trials of the oral contrast agent OMP for abdominal MR imaging showed this agent to be safe and efficacious. OMP increased the diagnostic efficacy of abdominal MR imaging in 2 of 3 cases examined, with a significant decrease in motion artefacts. Susceptibility contrast agents may also be of use in the evaluation of small lesions in the liver. Particulate material

  16. Standard Agent Framework 1

    1999-04-06

    The Standard Agent framework provides an extensible object-oriented development environment suitable for use in both research and applications projects. The SAF provides a means for constructing and customizing multi-agent systems through specialization of standard base classes (architecture-driven framework) and by composition of component classes (data driven framework). The standard agent system is implemented as an extensible object-centerd framework. Four concrete base classes are developed: (1) Standard Agency; (2) Standard Agent; (3) Human Factor, and (4)more » Resources. The object-centered framework developed and utilized provides the best comprimise between generality and flexibility available in agent development systems today.« less

  17. How do agents represent?

    NASA Astrophysics Data System (ADS)

    Ryan, Alex

    Representation is inherent to the concept of an agent, but its importance in complex systems has not yet been widely recognised. In this paper I introduce Peirce's theory of signs, which facilitates a definition of representation in general. In summary, representation means that for some agent, a model is used to stand in for another entity in a way that shapes the behaviour of the agent with respect to that entity. Representation in general is then related to the theories of representation that have developed within different disciplines. I compare theories of representation from metaphysics, military theory and systems theory. Additional complications arise in explaining the special case of mental representations, which is the focus of cognitive science. I consider the dominant theory of cognition — that the brain is a representational device — as well as the sceptical anti-representational response. Finally, I argue that representation distinguishes agents from non-representational objects: agents are objects capable of representation.

  18. Biological warfare agents.

    PubMed

    Thavaselvam, Duraipandian; Vijayaraghavan, Rajagopalan

    2010-07-01

    The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies.

  19. Biological warfare agents

    PubMed Central

    Thavaselvam, Duraipandian; Vijayaraghavan, Rajagopalan

    2010-01-01

    The recent bioterrorist attacks using anthrax spores have emphasized the need to detect and decontaminate critical facilities in the shortest possible time. There has been a remarkable progress in the detection, protection and decontamination of biological warfare agents as many instrumentation platforms and detection methodologies are developed and commissioned. Even then the threat of biological warfare agents and their use in bioterrorist attacks still remain a leading cause of global concern. Furthermore in the past decade there have been threats due to the emerging new diseases and also the re-emergence of old diseases and development of antimicrobial resistance and spread to new geographical regions. The preparedness against these agents need complete knowledge about the disease, better research and training facilities, diagnostic facilities and improved public health system. This review on the biological warfare agents will provide information on the biological warfare agents, their mode of transmission and spread and also the detection systems available to detect them. In addition the current information on the availability of commercially available and developing technologies against biological warfare agents has also been discussed. The risk that arise due to the use of these agents in warfare or bioterrorism related scenario can be mitigated with the availability of improved detection technologies. PMID:21829313

  20. Dioxin, agent orange

    SciTech Connect

    Gough, M.

    1986-01-01

    This book presents information on the following topics: dioxin, a prevalent problem; nobody wanted dioxin; agent organe and Vietnam; what we know about and may learn about agent orange and Veterans' health; agent organe and birth defects; dioxin in Missouri; 2, 4, 5-T: the U.S.' disappearing herbicide; Seveso: high-level environmental exposure; the nitro explosion; industrial exposures to dioxin; company behavior in the face of dioxin exposures; dioxin and specific cancers; animal tests of dioxin toxicity; dioxin decions; the present and the future.

  1. Riot Control Agents

    MedlinePlus

    ... your clothing, rapidly wash your entire body with soap and water, and get medical care as quickly ... agent from your skin with large amounts of soap and water. Washing with soap and water will ...

  2. Radioactive diagnostic agent

    SciTech Connect

    Shigematsu, A.; Aihara, M.; Matsuda, M.; Suzuki, A.; Tsuya, A.

    1984-02-07

    A radioactive diagnostic agent for renal cortex, adrenal cortex, myocardium, brain stem, spinal nerve, etc., which comprises as an essential component monoiodoacetic acid wherein the iodine atom is radioactive.

  3. Agent oriented programming

    NASA Technical Reports Server (NTRS)

    Shoham, Yoav

    1994-01-01

    The goal of our research is a methodology for creating robust software in distributed and dynamic environments. The approach taken is to endow software objects with explicit information about one another, to have them interact through a commitment mechanism, and to equip them with a speech-acty communication language. System-level applications include software interoperation and compositionality. A government application of specific interest is an infrastructure for coordination among multiple planners. Daily activity applications include personal software assistants, such as programmable email, scheduling, and new group agents. Research topics include definition of mental state of agents, design of agent languages as well as interpreters for those languages, and mechanisms for coordination within agent societies such as artificial social laws and conventions.

  4. Convertible MRI contrast: Sensing the delivery and release of anti-glioma nano-drugs

    NASA Astrophysics Data System (ADS)

    Zhang, Liang; Zhang, Zhongwei; Mason, Ralph P.; Sarkaria, Jann N.; Zhao, Dawen

    2015-05-01

    There is considerable interest in developing nanohybrids of imaging contrast agents and drugs for image-guided drug delivery. We have developed a strategy of utilizing manganese (Mn) to enhance the nano-encapsulation of arsenic trioxide (ATO). Formation of arsenite (As3+)-Mn precipitates in liposomes generates magnetic susceptibility effects, reflected as dark contrast on T2-weighted MRI. Intriguingly, following cell uptake, the As-Mn complex decomposes in response to low pH in endosome-lysosome releasing ionic As3+, the active form of ATO, and Mn2+, the T1 contrast agent that gives a bright signal. Glioblastoma (GBM) is well known for its high resistance to chemotherapy, e.g., temozolomide (TMZ). Building upon the previously established phosphatidylserine (PS)-targeted nanoplatform that has excellent GBM-targeting specificity, we now demonstrate the effectiveness of the targeted nanoformulated ATO for treating TMZ-resistant GBM cells and the ability of the convertible Mn contrast as a surrogate revealing the delivery and release of ATO.

  5. Convertible MRI contrast: Sensing the delivery and release of anti-glioma nano-drugs

    PubMed Central

    Zhang, Liang; Zhang, Zhongwei; Mason, Ralph P.; Sarkaria, Jann N.; Zhao, Dawen

    2015-01-01

    There is considerable interest in developing nanohybrids of imaging contrast agents and drugs for image-guided drug delivery. We have developed a strategy of utilizing manganese (Mn) to enhance the nano-encapsulation of arsenic trioxide (ATO). Formation of arsenite (As3+)-Mn precipitates in liposomes generates magnetic susceptibility effects, reflected as dark contrast on T2-weighted MRI. Intriguingly, following cell uptake, the As-Mn complex decomposes in response to low pH in endosome-lysosome releasing ionic As3+, the active form of ATO, and Mn2+, the T1 contrast agent that gives a bright signal. Glioblastoma (GBM) is well known for its high resistance to chemotherapy, e.g., temozolomide (TMZ). Building upon the previously established phosphatidylserine (PS)-targeted nanoplatform that has excellent GBM-targeting specificity, we now demonstrate the effectiveness of the targeted nanoformulated ATO for treating TMZ-resistant GBM cells and the ability of the convertible Mn contrast as a surrogate revealing the delivery and release of ATO. PMID:25962872

  6. Agent amplified communication

    SciTech Connect

    Kautz, H.; Selman, B.; Milewski, A.

    1996-12-31

    We propose an agent-based framework for assisting and simplifying person-to-person communication for information gathering tasks. As an example, we focus on locating experts for any specified topic. In our approach, the informal person-to-person networks that exist within an organization are used to {open_quotes}referral chain{close_quotes} requests for expertise. User-agents help automate this process. The agents generate referrals by analyzing records of e-mail communication patterns. Simulation results show that the higher responsiveness of an agent-based system can be effectively traded for the higher accuracy of a completely manual approach. Furthermore, preliminary experience with a group of users on a prototype system has shown that useful automatic referrals can be found in practice. Our experience with actual users has also shown that privacy concerns are central to the successful deployment of personal agents: an advanced agent-based system will therefore need to reason about issues involving trust and authority.

  7. Selective Estrogen Receptor β Agonist LY500307 as a Novel Therapeutic Agent for Glioblastoma

    PubMed Central

    Sareddy, Gangadhara R.; Li, Xiaonan; Liu, Jinyou; Viswanadhapalli, Suryavathi; Garcia, Lauren; Gruslova, Aleksandra; Cavazos, David; Garcia, Mike; Strom, Anders M.; Gustafsson, Jan-Ake; Tekmal, Rajeshwar Rao; Brenner, Andrew; Vadlamudi, Ratna K.

    2016-01-01

    Glioblastomas (GBM), deadly brain tumors, have greater incidence in males than females. Epidemiological evidence supports a tumor suppressive role of estrogen; however, estrogen as a potential therapy for GBM is limited due to safety concerns. Since GBM express ERβ, a second receptor for estrogen, targeting ERβ with a selective agonist may be a potential novel GBM therapy. In the present study, we examined the therapeutic effect of the selective synthetic ERβ agonist LY500307 using in vitro and in vivo GBM models. Treatment with LY500307 significantly reduced the proliferation of GBM cells with no activity on normal astrocytes in vitro. ERβ agonists promoted apoptosis of GBM cells, and mechanistic studies using RNA sequencing revealed that LY500307 modulated several pathways related to apoptosis, cell cycle, and DNA damage response. Further, LY500307 sensitized GBM cells to several FDA-approved chemotherapeutic drugs including cisplatin, lomustine and temozolomide. LY500307 treatment significantly reduced the in vivo tumor growth and promoted apoptosis of GBM tumors in an orthotopic model and improved the overall survival of tumor-bearing mice in the GL26 syngeneic glioma model. Our results demonstrate that LY500307 has potential as a therapeutic agent for GBM. PMID:27126081

  8. Severe sustained cholestatic hepatitis following temozolomide in a patient with glioblastoma multiforme: case study and review of data from the FDA adverse event reporting system.

    PubMed

    Sarganas, Giselle; Orzechowski, Hans D; Klimpel, Andreas; Thomae, Michael; Kauffmann, Wolfgang; Herbst, Hermann; Bronder, Elisabeth; Garbe, Edeltraut

    2012-05-01

    Glioblastoma multiforme (GBM) is the most frequent malignant brain tumor in adults. Its established first-line adjuvant treatment is radiotherapy in combination with temozolomide (TZM). Hematotoxicity is listed as a frequent adverse drug reaction in the US prescribing information and hepatotoxicity has been reported infrequently in the postmarketing period. We here present the case of a patient diagnosed with GBM who developed severe sustained cholestatic hepatitis following treatment with TZM. The cholestasis was not reversible after withdrawal of TZM during 6 months before the patient's death. Another 2 published case reports of sustained cholestasis following TZM treatment were identified; however, the sustained nature of cholestasis was not emphasized in these reports. Sixteen cases of cholestatic hepatitis/cholestasis associated with TZM were identified in the FDA spontaneous reporting system between 2007 and 2010. Information on the course of the cholestasis in these cases could not be retrieved. In the literature there are other published reports of hepatotoxicity associated with TZM that have reported reversibility upon withdrawal of the drug. Thus, TZM appears to cause different types of hepatotoxicity. Particular attention should be paid to sustained cholestasis as a very serious type of TZM-associated liver toxicity. PMID:22394496

  9. Severe sustained cholestatic hepatitis following temozolomide in a patient with glioblastoma multiforme: case study and review of data from the FDA adverse event reporting system

    PubMed Central

    Sarganas, Giselle; Orzechowski, Hans D.; Klimpel, Andreas; Thomae, Michael; Kauffmann, Wolfgang; Herbst, Hermann; Bronder, Elisabeth; Garbe, Edeltraut

    2012-01-01

    Glioblastoma multiforme (GBM) is the most frequent malignant brain tumor in adults. Its established first-line adjuvant treatment is radiotherapy in combination with temozolomide (TZM). Hematotoxicity is listed as a frequent adverse drug reaction in the US prescribing information and hepatotoxicity has been reported infrequently in the postmarketing period. We here present the case of a patient diagnosed with GBM who developed severe sustained cholestatic hepatitis following treatment with TZM. The cholestasis was not reversible after withdrawal of TZM during 6 months before the patient's death. Another 2 published case reports of sustained cholestasis following TZM treatment were identified; however, the sustained nature of cholestasis was not emphasized in these reports. Sixteen cases of cholestatic hepatitis/cholestasis associated with TZM were identified in the FDA spontaneous reporting system between 2007 and 2010. Information on the course of the cholestasis in these cases could not be retrieved. In the literature there are other published reports of hepatotoxicity associated with TZM that have reported reversibility upon withdrawal of the drug. Thus, TZM appears to cause different types of hepatotoxicity. Particular attention should be paid to sustained cholestasis as a very serious type of TZM-associated liver toxicity. PMID:22394496

  10. CUSP9* treatment protocol for recurrent glioblastoma: aprepitant, artesunate, auranofin, captopril, celecoxib, disulfiram, itraconazole, ritonavir, sertraline augmenting continuous low dose temozolomide

    PubMed Central

    Kast, Richard E.; Karpel-Massler, Georg; Halatsch, Marc-Eric

    2014-01-01

    CUSP9 treatment protocol for recurrent glioblastoma was published one year ago. We now present a slight modification, designated CUSP9*. CUSP9* drugs- aprepitant, artesunate, auranofin, captopril, celecoxib, disulfiram, itraconazole, sertraline, ritonavir, are all widely approved by regulatory authorities, marketed for non-cancer indications. Each drug inhibits one or more important growth-enhancing pathways used by glioblastoma. By blocking survival paths, the aim is to render temozolomide, the current standard cytotoxic drug used in primary glioblastoma treatment, more effective. Although esthetically unpleasing to use so many drugs at once, the closely similar drugs of the original CUSP9 used together have been well-tolerated when given on a compassionate-use basis in the cases that have come to our attention so far. We expect similarly good tolerability for CUSP9*. The combined action of this suite of drugs blocks signaling at, or the activity of, AKT phosphorylation, aldehyde dehydrogenase, angiotensin converting enzyme, carbonic anhydrase -2,- 9, -12, cyclooxygenase-1 and -2, cathepsin B, Hedgehog, interleukin-6, 5-lipoxygenase, matrix metalloproteinase -2 and -9, mammalian target of rapamycin, neurokinin-1, p-gp efflux pump, thioredoxin reductase, tissue factor, 20 kDa translationally controlled tumor protein, and vascular endothelial growth factor. We believe that given the current prognosis after a glioblastoma has recurred, a trial of CUSP9* is warranted. PMID:25211298

  11. Agent independent task planning

    NASA Technical Reports Server (NTRS)

    Davis, William S.

    1990-01-01

    Agent-Independent Planning is a technique that allows the construction of activity plans without regard to the agent that will perform them. Once generated, a plan is then validated and translated into instructions for a particular agent, whether a robot, crewmember, or software-based control system. Because Space Station Freedom (SSF) is planned for orbital operations for approximately thirty years, it will almost certainly experience numerous enhancements and upgrades, including upgrades in robotic manipulators. Agent-Independent Planning provides the capability to construct plans for SSF operations, independent of specific robotic systems, by combining techniques of object oriented modeling, nonlinear planning and temporal logic. Since a plan is validated using the physical and functional models of a particular agent, new robotic systems can be developed and integrated with existing operations in a robust manner. This technique also provides the capability to generate plans for crewmembers with varying skill levels, and later apply these same plans to more sophisticated robotic manipulators made available by evolutions in technology.

  12. Sunscreening agents: a review.

    PubMed

    Latha, M S; Martis, Jacintha; Shobha, V; Sham Shinde, Rutuja; Bangera, Sudhakar; Krishnankutty, Binny; Bellary, Shantala; Varughese, Sunoj; Rao, Prabhakar; Naveen Kumar, B R

    2013-01-01

    The increasing incidence of skin cancers and photodamaging effects caused by ultraviolet radiation has increased the use of sunscreening agents, which have shown beneficial effects in reducing the symptoms and reoccurrence of these problems. Many sunscreen compounds are in use, but their safety and efficacy are still in question. Efficacy is measured through indices, such as sun protection factor, persistent pigment darkening protection factor, and COLIPA guidelines. The United States Food and Drug Administration and European Union have incorporated changes in their guidelines to help consumers select products based on their sun protection factor and protection against ultraviolet radiation, whereas the Indian regulatory agency has not yet issued any special guidance on sunscreening agents, as they are classified under cosmetics. In this article, the authors discuss the pharmacological actions of sunscreening agents as well as the available formulations, their benefits, possible health hazards, safety, challenges, and proper application technique. New technologies and scope for the development of sunscreening agents are also discussed as well as the role of the physician in patient education about the use of these agents.

  13. MpcAgent

    2013-11-29

    MpcAgent software is a module for the VolltronLite platform from PNNL that regulates the operation of rooftop air conditioning units in small to medium commercial buildings for the purpose of reducing peak power consumption. The MpcAgent accomplishes this by restricting the number of units that may operate simultaneously and using a model predictive control strategy to select which units to operate in each control period. The outcome of this control is effective control of themore » building air temperature at the user specified set point while avoiding expensive peak demand charges that result from running all HVAC units simultaneously.« less

  14. MpcAgent

    SciTech Connect

    Nutaro, James

    2013-11-29

    MpcAgent software is a module for the VolltronLite platform from PNNL that regulates the operation of rooftop air conditioning units in small to medium commercial buildings for the purpose of reducing peak power consumption. The MpcAgent accomplishes this by restricting the number of units that may operate simultaneously and using a model predictive control strategy to select which units to operate in each control period. The outcome of this control is effective control of the building air temperature at the user specified set point while avoiding expensive peak demand charges that result from running all HVAC units simultaneously.

  15. Agent Persuasion Mechanism of Acquaintance

    NASA Astrophysics Data System (ADS)

    Jinghua, Wu; Wenguang, Lu; Hailiang, Meng

    Agent persuasion can improve negotiation efficiency in dynamic environment based on its initiative and autonomy, and etc., which is being affected much more by acquaintance. Classification of acquaintance on agent persuasion is illustrated, and the agent persuasion model of acquaintance is also illustrated. Then the concept of agent persuasion degree of acquaintance is given. Finally, relative interactive mechanism is elaborated.

  16. 13 CFR 108.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent. 108.1620 Section 108.1620 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION NEW MARKETS VENTURE CAPITAL (âNMVCâ) PROGRAM SBA...

  17. Battlefield agent collaboration

    NASA Astrophysics Data System (ADS)

    Budulas, Peter P.; Young, Stuart H.; Emmerman, Philip J.

    2001-09-01

    Small air and ground physical agents (robots) will be ubiquitous on the battlefield of the 21st century, principally to lower the exposure to harm of our ground forces in urban and open terrain scenarios. Teams of small collaborating physical agents conducting tasks such as Reconnaissance, Surveillance, and Target Acquisition (RSTA), intelligence, chemical and biological agent detection, logistics, decoy, sentry; and communications relay will have advanced sensors, communications, and mobility characteristics. It is anticipated that there will be many levels of individual and team collaboration between the soldier and robot, robot to robot, and robot to mother ship. This paper presents applications and infrastructure components that illustrate each of these levels. As an example, consider the application where a team of twenty small robots must rapidly explore and define a building complex. Local interactions and decisions require peer to peer collaboration. Global direction and information fusion warrant a central team control provided by a mother ship. The mother ship must effectively deliver/retrieve, service, and control these robots as well as fuse the information gathered by these highly mobile robot teams. Any level of collaboration requires robust communications, specifically a mobile ad hoc network. The application of fixed ground sensors and mobile robots is also included in this paper. This paper discusses on going research at the U.S. Army Research Laboratory that supports the development of multi-robot collaboration. This research includes battlefield visualization, intelligent software agents, adaptive communications, sensor and information fusion, and multi-modal human computer interaction.

  18. Mobility control agent

    SciTech Connect

    Argabright, P.A.; Phillips, B.L.; Rhudy, J.S.

    1983-05-17

    Polymer mobility control agents useful in supplemental oil recovery processes, which give improved reciprocal relative mobilities, are prepared by initiating the polymerization of a monomer containing a vinyl group with a catalyst comprising a persulfate and ferrous ammonium sulfate. The vinyl monomer is an acrylyl, a vinyl cyanide, a styryl and water soluble salts thereof.

  19. E-Learning Agents

    ERIC Educational Resources Information Center

    Gregg, Dawn G.

    2007-01-01

    Purpose: The purpose of this paper is to illustrate the advantages of using intelligent agents to facilitate the location and customization of appropriate e-learning resources and to foster collaboration in e-learning environments. Design/methodology/approach: This paper proposes an e-learning environment that can be used to provide customized…

  20. Remote Agent Experiment

    NASA Technical Reports Server (NTRS)

    Benard, Doug; Dorais, Gregory A.; Gamble, Ed; Kanefsky, Bob; Kurien, James; Millar, William; Muscettola, Nicola; Nayak, Pandu; Rouquette, Nicolas; Rajan, Kanna; Norvig, Peter (Technical Monitor)

    2000-01-01

    Remote Agent (RA) is a model-based, reusable artificial intelligence (At) software system that enables goal-based spacecraft commanding and robust fault recovery. RA was flight validated during an experiment on board of DS1 between May 17th and May 21th, 1999.

  1. Can Subscription Agents Survive?

    ERIC Educational Resources Information Center

    Tuttle, Marcia

    1985-01-01

    With the saturation of traditional markets for their services, subscription agents have evolved from orders and invoices to serving customers by communicating with librarians and publishers and making automated and paper products available. Magazine fulfillment centers, publisher discounts, and electronic publishing will influence the subscription…

  2. On the Performance of Trimetazidine and Vitamin E as Pharmacoprotection Agents in Cyclosporin A-Induced Toxicity

    PubMed Central

    Cristina, De la Cruz Rodríguez Lilia; del Rosario, Rey María; Carmen Rosa, Araujo; Ana Veronica, Oldano

    2013-01-01

    The immunosuppressant drug cyclosporin A (CyA) has been used in diseases with immunological basis and in transplant patients. Nephrotoxicity and hepatotoxicity are the main adverse effects of this drug. To find a protective drug against those effects we assayed the cardioprotector Trimetazidine (TMZ) and vitamin E, used as nutritional supplements to alleviate oxidative stress. Six groups of eight male Wistar rats each were prepared (groups A–F): A, control; B, vitamin E (10 mg/Kg/day); C, TMZ (20 mg/Kg/day); D, 25 mg/Kg/day CyA; E, CyA and vitamin E (25 mg/Kg/day CyA + 10 mg/Kg/day Vit E); F, TMZ for 20 days (20 mg/kg/day); and then CyA (25 mg/kg/day) and TMZ (20 mg/Kg/day). The experiment lasted 120 days. The exposure of rats to CyA promoted nephrotoxicity and hepatotoxicity with an increase in serum urea, creatinine, and glutamate dehydrogenase (GLDH). Structural and ultrastructural studies of liver and kidney were performed. Group D showed adverse effects induced by CyA since statistically significant differences were found with respect to the control group (A). Vitamin E (E) showed no protective effect. Pretreatment with TMZ (F) attenuated the adverse effects of CyA. We conclude that CyA-induced nephrotoxicity and hepatotoxicity are attenuated by the cytoprotective effect of TMZ. TMZ inhibits the reabsorption and, consequently, the accumulation of CyA in the cell. The antioxidant capacity of vitamin E did not improve the effect of CyA. PMID:23691353

  3. Durable response of glioblastoma to adjuvant therapy consisting of temozolomide and a weekly dose of AMD3100 (plerixafor), a CXCR4 inhibitor, together with lapatinib, metformin and niacinamide

    PubMed Central

    Rios, Adan; Hsu, Sigmund H.; Blanco, Angel; Buryanek, Jamie; Day, Arthur L.; McGuire, Mary F.; Brown, Robert E.

    2016-01-01

    Glioblastoma multiforme (GBM) is a CNS (central nervous system) malignancy with a low cure rate. Median time to progression after standard treatment is 7 months and median overall survival is 15 months [1]. Post-treatment vasculogenesis promoted by recruitment of bone marrow derived cells (BMDCs, CD11b+ myelomonocytes) is one of main mechanisms of GBM resistance to initial chemoradiotherapy treatment [2]. Local secretion of SDF-1, cognate ligand of BMDCs CXCR4 receptors attracts BMDCs to the post-radiation tumor site.[3]. This SDF-1 hypoxia-dependent effect can be blocked by AMD3100 (plerixafor) [4]. We report a GBM case treated after chemo- radiotherapy with plerixafor and a combination of an mTOR, a Sirt1 and an EGFRvIII inhibitor. After one year temozolomide and the EGFRvIII inhibitor were stopped. Plerixafor, and the MTOR and Sirt-1 inhibitors were continued. He is in clinical and radiologic remission 30 months from the initiation of his adjuvant treatment. To our knowledge, this is the first report of a patient treated for over two years with a CXCR4 inhibitor (plerixafor), as part of his adjuvant treatment. We believe there is sufficient experimental evidence to consider AMD3100 (plerixafor) part of the adjuvant treatment of GBM. Significance The adjuvant inhibition of GBM vasculogenesis(a process different from local angiogenesis) by specifically blocking the migration of BMDCs to the primary tumor site with inhibitors of the CXCR4/SDF-1 axis represents a potential novel therapeutic approach to GBM. There is significant pre-clinical evidence and validation for its use as demonstrated in a patient derived tumor xenograft model of GBM. Together with other specific anti-tumoral therapies, the active inhibition of vasculogenesis in the adjuvant treatment of GBM is deserving of further exploration. PMID:27489862

  4. Patients With Proneural Glioblastoma May Derive Overall Survival Benefit From the Addition of Bevacizumab to First-Line Radiotherapy and Temozolomide: Retrospective Analysis of the AVAglio Trial

    PubMed Central

    Sandmann, Thomas; Bourgon, Richard; Garcia, Josep; Li, Congfen; Cloughesy, Timothy; Chinot, Olivier L.; Wick, Wolfgang; Nishikawa, Ryo; Mason, Warren; Henriksson, Roger; Saran, Frank; Lai, Albert; Moore, Nicola; Kharbanda, Samir; Peale, Franklin; Hegde, Priti; Abrey, Lauren E.; Phillips, Heidi S.; Bais, Carlos

    2015-01-01

    Purpose The AVAglio (Avastin in Glioblastoma) and RTOG-0825 randomized, placebo-controlled phase III trials in newly diagnosed glioblastoma reported prolonged progression-free survival (PFS), but not overall survival (OS), with the addition of bevacizumab to radiotherapy plus temozolomide. To establish whether certain patient subgroups derived an OS benefit from the addition of bevacizumab to first-line standard-of-care therapy, AVAglio patients were retrospectively evaluated for molecular subtype, and bevacizumab efficacy was assessed for each patient subgroup. Patients and Methods A total of 349 pretreatment specimens (bevacizumab arm, n = 171; placebo arm, n = 178) from AVAglio patients (total, N = 921) were available for biomarker analysis. Samples were profiled for gene expression and isocitrate dehydrogenase 1 (IDH1) mutation status and classified into previously identified molecular subtypes. PFS and OS were assessed within each subtype. Results A multivariable analysis accounting for prognostic covariates revealed that bevacizumab conferred a significant OS advantage versus placebo for patients with proneural IDH1 wild-type tumors (17.1 v 12.8 months, respectively; hazard ratio, 0.43; 95% CI, 0.26 to 0.73; P = .002). This analysis also revealed an interaction between the proneural subtype biomarker and treatment arm (P = .023). The group of patients with mesenchymal and proneural tumors derived a PFS benefit from bevacizumab compared with placebo; however, this translated to an OS benefit in the proneural subset only. Conclusion Retrospective analysis of AVAglio data suggests that patients with IDH1 wild-type proneural glioblastoma may derive an OS benefit from first-line bevacizumab treatment. The predictive value of the proneural subtype observed in AVAglio should be validated in an independent data set. PMID:26124478

  5. Asparagine Depletion Potentiates the Cytotoxic Effect of Chemotherapy Against Brain Tumors

    PubMed Central

    Panosyan, Eduard H.; Wang, Yuntao; Xia, Peng; Lee, Wai-Nang Paul; Pak, Youngju; Laks, Dan R.; Lin, Henry J.; Moore, Theodore B.; Cloughesy, Timothy F.; Kornblum, Harley I.; Lasky, Joseph L.

    2014-01-01

    Targeting amino acid metabolism has therapeutic implications for aggressive brain tumors. Asparagine is an amino acid that is synthesized by normal cells. However, some cancer cells lack asparagine synthetase (ASNS), the key enzyme for asparagine synthesis. Asparaginase (ASNase) contributes to eradication of acute leukemia by decreasing asparagine levels in serum and cerebrospinal fluid. However, leukemic cells may become ASNase-resistant by up-regulating ASNS. High expression of ASNS has also been associated with biological aggressiveness of other cancers, including gliomas. Here, the impact of enzymatic depletion of asparagine on proliferation of brain tumor cells was determined. ASNase was used as monotherapy or in combination with conventional chemotherapeutic agents. Viability assays for ASNase-treated cells demonstrated significant growth reduction in multiple cell lines. This effect was reversed by glutamine in a dose-dependent manner -- as expected, because glutamine is the main amino group donor for asparagine synthesis. ASNase treatment also reduced sphere formation by medulloblastoma and primary glioblastoma cells. ASNase-resistant glioblastoma cells exhibited elevated levels of ASNS mRNA. ASNase co-treatment significantly enhanced gemcitabine or etoposide cytotoxicity against glioblastoma cells. Xenograft tumors in vivo showed no significant response to ASNase monotherapy and little response to temozolomide (TMZ) alone. However, combinatorial therapy with ASNase and TMZ resulted in significant growth suppression for an extended duration of time. Taken together, these findings indicate that amino acid depletion warrants further investigation as adjunctive therapy for brain tumors. PMID:24505127

  6. Concurrent therapy to enhance radiotherapeutic outcomes in glioblastoma

    PubMed Central

    2016-01-01

    Glioblastoma is one of the most fatal and incurable human cancers characterized by nuclear atypia, mitotic activity, intense microvascular proliferation and necrosis. The current standard of care includes maximal safe surgical resection followed by radiation therapy (RT) with concurrent and adjuvant temozolomide (TMZ). The prognosis remains poor with median survival of 14.6 months with RT plus TMZ. Majority will have a recurrence within 2 years from diagnosis despite adequate treatment. Radiosensitizers, radiotherapy dose escalation and altered fractionation have failed to improve outcome. The molecular biology of glioblastoma is complex and poses treatment challenges. High rate of mutation, genotypic and phenotypic heterogeneity, rapid development of resistance, existence of blood-brain barrier (BBB), multiple intracellular and intercellular signalling pathways, over-expression of growth factor receptors, angiogenesis and antigenic diversity renders the tumor cells differentially susceptible to various treatment modalities. Thus, the treatment strategies require personalised or individualized approach based on the characteristics of tumor. Several targeted agents have been evaluated in clinical trials but the results have been modest despite these advancements. This review summarizes the current standard of care, results of concurrent chemoradiation trials, evolving innovative treatments that use targeted therapy with standard chemoradiation or RT alone, outcome of various recent trials and future outlook. PMID:26904576

  7. Emulsified blasting agents

    SciTech Connect

    Chironis, N.P.

    1985-01-01

    This article describes an improved blasting agent which is being tailor-blended with bulk ANFO to provide more explosive energy and better water resistance when the blasting conditions call for it. The proportions of the emulsion/ANFO mix are easily changed at the blasthole site because both materials can be selectively mixed in modified bulk-explosive trucks before loading the blasting agents into the holes. Such blends are helping speed stripping at a number of surface mines and are leading to cost savings in production, ranging from 10% to 30%, depending upon application, even though the actual cost of a blend will be higher than if bulk ANFO is used alone.

  8. Rigid bifunctional chelating agents

    DOEpatents

    Sweet, Mark P.; Mease, Ronnie C.; Srivastava, Suresh C.

    2000-02-08

    Bicyclo[2.2.2]octane-2,3 diamine-N,N,N',N'-tetraacetic acids (BODTA) and bicyclo[2.2.1]heptane-2,3 diamine-N,N,N',N'-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.

  9. Rigid bifunctional chelating agents

    DOEpatents

    Sweet, M.P.; Mease, R.C.; Srivastava, S.C.

    1998-07-21

    Bicyclo[2.2.2] octane-2,3 diamine-N,N,N`,N`-tetraacetic acids (BODTA) and bicyclo[2.2.1] heptane-2,3 diamine-N,N,N`,N`-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.

  10. Rigid bifunctional chelating agents

    DOEpatents

    Sweet, Mark P.; Mease, Ronnie C.; Srivastava, Suresh C.

    1998-07-21

    Bicyclo›2.2.2! octane-2,3 diamine-N,N,N',N'-tetraacetic acids (BODTA) and bicyclo›2.2.1! heptane-2,3 diamine-N,N,N',N'-tetraacetic acid (BHDTA) are chelating agents useful in forming detectably labeled bioconjugate compounds for diagnostic and therapeutic purposes. New compounds and processes of forming BODTA and BHDTA are disclosed. Radioimmunoconjugates of the present invention show high and prolonged tumor uptake with low normal tissue uptakes.

  11. Surface polymerization agents

    SciTech Connect

    Taylor, C.; Wilkerson, C.

    1996-12-01

    This is the final report of a 1-year, Laboratory-Directed R&D project at LANL. A joint technical demonstration was proposed between US Army Missile Command (Redstone Arsenal) and LANL. Objective was to demonstrate that an unmanned vehicle or missile could be used as a platform to deliver a surface polymerization agent in such a manner as to obstruct the filters of an air-breathing mechanism, resulting in operational failure.

  12. Transferrin-Targeted Nanoparticles Containing Zoledronic Acid as a Potential Tool to Inhibit Glioblastoma Growth.

    PubMed

    Salzano, G; Zappavigna, S; Luce, A; D'Onofrio, N; Balestrieri, M L; Grimaldi, A; Lusa, S; Ingrosso, D; Artuso, S; Porru, M; Leonetti, C; Caraglia, M; De Rosa, G

    2016-04-01

    The treatment of glioblastoma (GBM) is a challenge for the biomedical research since cures remain elusive. Its current therapy, consisted on surgery, radiotherapy, and concomitant chemotherapy with temozolomide (TMZ), is often uneffective. Here, we proposed the use of zoledronic acid (ZOL) as a potential agent for the treatment of GBM. Our group previously developed self-assembling nanoparticles, also named PLCaPZ NPs, to use ZOL in the treatment of prostate cancer. Here, we updated the previously developed nanoparticles (NPs) by designing transferrin (Tf)-targeted self-assembling NPs, also named Tf-PLCaPZ NPs, to use ZOL in the treatment of brain tumors, e.g., GBM. The efficacy of Tf-PLCaPZ NPs was evaluated in different GBM cell lines and in an animal model of GBM, in comparison with PLCaPZ NPs and free ZOL. Tf-PLCaPZ NPs were characterized by a narrow size distribution and a high incorporation efficiency of ZOL. Moreover, the presence of Tf significantly reduced the hemolytic activity of the formulation. In vitro, in LN229 cells, a significant uptake and cell growth inhibition after treatment with Tf-PLCaPZ NPs was achieved. Moreover, the sequential therapy of TMZ and Tf-PLCaPZ NPs lead to a superior therapeutic activity compared to their single administration. The results obtained in mice xenografted with U373MG, revealed a significant anticancer activity of Tf-PLCaPZ NPs, while the tumors remained unaffected with free TMZ. These promising results introduce a novel type of easy-to-obtain NPs for the delivery of ZOL in the treatment of GBM tumors.

  13. Transferrin-Targeted Nanoparticles Containing Zoledronic Acid as a Potential Tool to Inhibit Glioblastoma Growth.

    PubMed

    Salzano, G; Zappavigna, S; Luce, A; D'Onofrio, N; Balestrieri, M L; Grimaldi, A; Lusa, S; Ingrosso, D; Artuso, S; Porru, M; Leonetti, C; Caraglia, M; De Rosa, G

    2016-04-01

    The treatment of glioblastoma (GBM) is a challenge for the biomedical research since cures remain elusive. Its current therapy, consisted on surgery, radiotherapy, and concomitant chemotherapy with temozolomide (TMZ), is often uneffective. Here, we proposed the use of zoledronic acid (ZOL) as a potential agent for the treatment of GBM. Our group previously developed self-assembling nanoparticles, also named PLCaPZ NPs, to use ZOL in the treatment of prostate cancer. Here, we updated the previously developed nanoparticles (NPs) by designing transferrin (Tf)-targeted self-assembling NPs, also named Tf-PLCaPZ NPs, to use ZOL in the treatment of brain tumors, e.g., GBM. The efficacy of Tf-PLCaPZ NPs was evaluated in different GBM cell lines and in an animal model of GBM, in comparison with PLCaPZ NPs and free ZOL. Tf-PLCaPZ NPs were characterized by a narrow size distribution and a high incorporation efficiency of ZOL. Moreover, the presence of Tf significantly reduced the hemolytic activity of the formulation. In vitro, in LN229 cells, a significant uptake and cell growth inhibition after treatment with Tf-PLCaPZ NPs was achieved. Moreover, the sequential therapy of TMZ and Tf-PLCaPZ NPs lead to a superior therapeutic activity compared to their single administration. The results obtained in mice xenografted with U373MG, revealed a significant anticancer activity of Tf-PLCaPZ NPs, while the tumors remained unaffected with free TMZ. These promising results introduce a novel type of easy-to-obtain NPs for the delivery of ZOL in the treatment of GBM tumors. PMID:27301207

  14. Electrochemical monitoring of the interaction between Temozolamide and nucleic acids by using disposable pencil graphite electrodes.

    PubMed

    Altay, Cansu; Eksin, Ece; Congur, Gulsah; Erdem, Arzum

    2015-11-01

    Temozolomide (TMZ) is an anticancer drug used for the treatment of adult brain tumour and skin cancer. The biomolecular interaction between TMZ and DNA was investigated for the first time in this study using disposable pencil graphite electrodes (PGEs) in combination with electrochemical techniques. The surface confined interactions between TMZ and different type of nucleic acids were performed. Before/after surface confined interaction process, the oxidation signals of TMZ, guanine and adenine were measured using differential pulse voltammetry (DPV) and PGE and accordingly, the changes at the oxidation signals were evaluated. The detection limit (DL) was also estimated based on the oxidation signal of TMZ. The interaction of TMZ with single stranded poly [A], poly [G], or double stranded poly [A]-poly[T] and poly [G]-poly[C] was also explored. Moreover, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) techniques were utilized for detection the interaction between TMZ and DNA. The features of this single-use electrochemical sensor was discussed in comparison to other reports that were developed for TMZ detection.

  15. Collaborating with Autonomous Agents

    NASA Technical Reports Server (NTRS)

    Trujillo, Anna C.; Cross, Charles D.; Fan, Henry; Hempley, Lucas E.; Motter, Mark A.; Neilan, James H.; Qualls, Garry D.; Rothhaar, Paul M.; Tran, Loc D.; Allen, B. Danette

    2015-01-01

    With the anticipated increase of small unmanned aircraft systems (sUAS) entering into the National Airspace System, it is highly likely that vehicle operators will be teaming with fleets of small autonomous vehicles. The small vehicles may consist of sUAS, which are 55 pounds or less that typically will y at altitudes 400 feet and below, and small ground vehicles typically operating in buildings or defined small campuses. Typically, the vehicle operators are not concerned with manual control of the vehicle; instead they are concerned with the overall mission. In order for this vision of high-level mission operators working with fleets of vehicles to come to fruition, many human factors related challenges must be investigated and solved. First, the interface between the human operator and the autonomous agent must be at a level that the operator needs and the agents can understand. This paper details the natural language human factors e orts that NASA Langley's Autonomy Incubator is focusing on. In particular these e orts focus on allowing the operator to interact with the system using speech and gestures rather than a mouse and keyboard. With this ability of the system to understand both speech and gestures, operators not familiar with the vehicle dynamics will be able to easily plan, initiate, and change missions using a language familiar to them rather than having to learn and converse in the vehicle's language. This will foster better teaming between the operator and the autonomous agent which will help lower workload, increase situation awareness, and improve performance of the system as a whole.

  16. Hydroxypyridonate and hydroxypyrimidinone chelating agents

    DOEpatents

    Raymond, Kenneth N.; Doble, Daniel M.; Sunderland, Christopher J.; Thompson, Marlon

    2005-01-25

    The present invention provides hydroxypyridinone and hydroxypyrimidone chelating agents. Also provides are Gd(III) complexes of these agents, which are useful as contrast enhancing agents for magnetic resonance imaging. The invention also provides methods of preparing the compounds of the invention, as well as methods of using the compounds in magnetic resonance imaging applications.

  17. Chemical warfare agents

    PubMed Central

    Ganesan, K.; Raza, S. K.; Vijayaraghavan, R.

    2010-01-01

    Among the Weapons of Mass Destruction, chemical warfare (CW) is probably one of the most brutal created by mankind in comparison with biological and nuclear warfare. Chemical weapons are inexpensive and are relatively easy to produce, even by small terrorist groups, to create mass casualties with small quantities. The characteristics of various CW agents, general information relevant to current physical as well as medical protection methods, detection equipment available and decontamination techniques are discussed in this review article. A brief note on Chemical Weapons Convention is also provided. PMID:21829312

  18. Holograms as Teaching Agents

    NASA Astrophysics Data System (ADS)

    Walker, Robin A.

    2013-02-01

    Hungarian physicist Dennis Gabor won the Pulitzer Prize for his 1947 introduction of basic holographic principles, but it was not until the invention of the laser in 1960 that research scientists, physicians, technologists and the general public began to seriously consider the interdisciplinary potentiality of holography. Questions around whether and when Three-Dimensional (3-D) images and systems would impact American entertainment and the arts would be answered before educators, instructional designers and students would discover how much Three-Dimensional Hologram Technology (3DHT) would affect teaching practices and learning environments. In the following International Symposium on Display Holograms (ISDH) poster presentation, the author features a traditional board game as well as a reflection hologram to illustrate conventional and evolving Three-Dimensional representations and technology for education. Using elements from the American children's toy Operation® (Hasbro, 2005) as well as a reflection hologram of a human brain (Ko, 1998), this poster design highlights the pedagogical effects of 3-D images, games and systems on learning science. As teaching agents, holograms can be considered substitutes for real objects, (human beings, organs, and animated characters) as well as agents (pedagogical, avatars, reflective) in various learning environments using many systems (direct, emergent, augmented reality) and electronic tools (cellphones, computers, tablets, television). In order to understand the particular importance of utilizing holography in school, clinical and public settings, the author identifies advantages and benefits of using 3-D images and technology as instructional tools.

  19. Lipid-lowering agents.

    PubMed

    Ewang-Emukowhate, Mfon; Wierzbicki, Anthony S

    2013-09-01

    The role of lipid lowering in reducing the risk of mortality and morbidity from cardiovascular disease (CVD) is well established. Treatment particularly aimed at decreasing low-density lipoprotein cholesterol (LDL-C) is effective in reducing the risk of death from coronary heart disease and stroke. Statins form the cornerstone of treatment. However, in some individuals with a high risk of CVD who are unable to achieve their target LDL-C due to either intolerance or lack of efficacy, there is the need for alternative therapies. This review provides an overview of the different classes of currently available lipid-lowering medications including statins, fibrates, bile acid sequestrants (resins), and omega-3 fatty acids. Data are presented on their indications, pharmacology, and the relevant end point clinical trial data with these drugs. It also discusses the human trial data on some novel therapeutic agents that are being developed including those for homozygous familial hypercholesterolemia--the antisense oligonucleotide mipomersen and the microsomal transfer protein inhibitor lomitapide. Data are presented on phase II and III trials on agents with potentially wider applications, cholesterol ester transfer protein inhibitors and proprotein convertase subtilisin kexin 9 inhibitors. The data on a licensed gene therapy for lipoprotein lipase deficiency are also presented. PMID:23811423

  20. [Bacteriophages as antibacterial agents].

    PubMed

    Shasha, Shaul M; Sharon, Nehama; Inbar, Michael

    2004-02-01

    Bacteriophages are viruses that only infect bacteria. They have played an important role in the development of molecular biology and have been used as anti-bacterial agents. Since their independent discovery by Twort and d'Herelle, they have been extensively used to prevent and treat bacterial infections, mainly in Eastern Europe and the former Soviet Union. In western countries this method has been sporadically employed on humans and domesticated animals. However, the discovery and widespread use of antibiotics, coupled with doubts about the efficacy of phage therapy, led to an eclipse in the use of phage in medicine. The emergence of antibiotic resistant bacteria, especially strains that are multiply resistant, has resulted in a renewed interest in alternatives to conventional drugs. One of the possible replacements for antibiotics is the use of bacteriophages as antimicrobial agents. This brief review aims to describe the history of bacteriophage and early clinical studies on their use in bacterial disease prophylaxis and therapy, and discuss the advantages and disadvantages of bacteriophage in this regard.

  1. Lipid-lowering agents.

    PubMed

    Ewang-Emukowhate, Mfon; Wierzbicki, Anthony S

    2013-09-01

    The role of lipid lowering in reducing the risk of mortality and morbidity from cardiovascular disease (CVD) is well established. Treatment particularly aimed at decreasing low-density lipoprotein cholesterol (LDL-C) is effective in reducing the risk of death from coronary heart disease and stroke. Statins form the cornerstone of treatment. However, in some individuals with a high risk of CVD who are unable to achieve their target LDL-C due to either intolerance or lack of efficacy, there is the need for alternative therapies. This review provides an overview of the different classes of currently available lipid-lowering medications including statins, fibrates, bile acid sequestrants (resins), and omega-3 fatty acids. Data are presented on their indications, pharmacology, and the relevant end point clinical trial data with these drugs. It also discusses the human trial data on some novel therapeutic agents that are being developed including those for homozygous familial hypercholesterolemia--the antisense oligonucleotide mipomersen and the microsomal transfer protein inhibitor lomitapide. Data are presented on phase II and III trials on agents with potentially wider applications, cholesterol ester transfer protein inhibitors and proprotein convertase subtilisin kexin 9 inhibitors. The data on a licensed gene therapy for lipoprotein lipase deficiency are also presented.

  2. [New agents for hypercholesterolemia].

    PubMed

    Pintó, Xavier; García Gómez, María Carmen

    2016-02-19

    An elevated proportion of high cardiovascular risk patients do not achieve the therapeutic c-LDL goals. This owes to physicians' inappropriate or insufficient use of cholesterol lowering medications or to patients' bad tolerance or therapeutic compliance. Another cause is an insufficient efficacy of current cholesterol lowering drugs including statins and ezetimibe. In addition, proprotein convertase subtilisin kexin type 9 inhibitors are a new cholesterol lowering medications showing safety and high efficacy to reduce c-LDL in numerous already performed or underway clinical trials, potentially allowing an optimal control of hypercholesterolemia in most patients. Agents inhibiting apolipoprotein B synthesis and microsomal transfer protein are also providing a new potential to decrease cholesterol in patients with severe hypercholesterolemia and in particular in homozygote familial hypercholesterolemia. Last, cholesteryl ester transfer protein inhibitors have shown powerful effects on c-HDL and c-LDL, although their efficacy in cardiovascular prevention and safety has not been demonstrated yet. We provide in this article an overview of the main characteristics of therapeutic agents for hypercholesterolemia, which have been recently approved or in an advanced research stage.

  3. Advances in antithrombotic agents.

    PubMed

    Chakrabarti, Ranjan; Das, Saibal Kumar

    2007-07-01

    Thrombosis is the condition where an imbalance in the homeostatic mechanism results in unwanted intravascular thrombus formation. Imbalances in this highly regulated process of coagulation and anticoagulation can lead to a variety of pathophysiological conditions leading to stroke, pulmonary heart attack and other serious conditions. In the western world, thromboembolic diseases are the leading cause of morbidity and mortality. Remarkable progress has occurred over the last decade in the development of antithrombotic drugs, which can be classified into 3 major categories - Anticoagulants, Antiplatelets and thrombolytics. Increased understanding of the pathobiology of thrombotic and vascular disorders has helped researchers to target novel pathways involving the coagulation, thrombolytic, fibrinolytic and integrin systems. Traditionally aspirin and unfractionated heparin was used for myocardial infarction. Newer antiplatelet agents such as, clopidogrel, GP IIb/IIIa inhibitors, low molecular weight heparin, direct thrombin inhibitors and several improved thrombolytic agents have been introduced for clinical use. This review will discuss different important drugs, which have been launched in recent years and also some new targets pursued by different companies. PMID:17630943

  4. Flexible, secure agent development framework

    DOEpatents

    Goldsmith; Steven Y.

    2009-04-07

    While an agent generator is generating an intelligent agent, it can also evaluate the data processing platform on which it is executing, in order to assess a risk factor associated with operation of the agent generator on the data processing platform. The agent generator can retrieve from a location external to the data processing platform an open site that is configurable by the user, and load the open site into an agent substrate, thereby creating a development agent with code development capabilities. While an intelligent agent is executing a functional program on a data processing platform, it can also evaluate the data processing platform to assess a risk factor associated with performing the data processing function on the data processing platform.

  5. Fluoroquinolone antimicrobial agents.

    PubMed Central

    Wolfson, J S; Hooper, D C

    1989-01-01

    The fluoroquinolones, a new class of potent orally absorbed antimicrobial agents, are reviewed, considering structure, mechanisms of action and resistance, spectrum, variables affecting activity in vitro, pharmacokinetic properties, clinical efficacy, emergence of resistance, and tolerability. The primary bacterial target is the enzyme deoxyribonucleic acid gyrase. Bacterial resistance occurs by chromosomal mutations altering deoxyribonucleic acid gyrase and decreasing drug permeation. The drugs are bactericidal and potent in vitro against members of the family Enterobacteriaceae, Haemophilus spp., and Neisseria spp., have good activity against Pseudomonas aeruginosa and staphylococci, and (with several exceptions) are less potent against streptococci and have fair to poor activity against anaerobic species. Potency in vitro decreases in the presence of low pH, magnesium ions, or urine but is little affected by different media, increased inoculum, or serum. The effects of the drugs in combination with a beta-lactam or aminoglycoside are often additive, occasionally synergistic, and rarely antagonistic. The agents are orally absorbed, require at most twice-daily dosing, and achieve high concentrations in urine, feces, and kidney and good concentrations in lung, bone, prostate, and other tissues. The drugs are efficacious in treatment of a variety of bacterial infections, including uncomplicated and complicated urinary tract infections, bacterial gastroenteritis, and gonorrhea, and show promise for therapy of prostatitis, respiratory tract infections, osteomyelitis, and cutaneous infections, particularly when caused by aerobic gram-negative bacilli. Fluoroquinolones have also proved to be efficacious for prophylaxis against travelers' diarrhea and infection with gram-negative bacilli in neutropenic patients. The drugs are effective in eliminating carriage of Neisseria meningitidis. Patient tolerability appears acceptable, with gastrointestinal or central nervous

  6. Biological agents and pregnancy.

    PubMed

    Ekblad, U

    1995-08-01

    Pregnant women are exposed to many biological, eg microbial, agents, which are potentially harmful to the fetus. The reported rates of vertical transmission of hepatitis B and human immunodeficiency virus vary between 3 to 90% and 0 to 65%, respectively. The susceptibility to hepatitis B and human immunodeficiency infection is increased in pregnant physicians, midwives, and nurses because of the bloodborne nature of these viruses. Also, TORCH (toxoplasmosis-rubella-cytomegalovirus-herpes) infections, acquired during pregnancy, may result in congenital infection, and serious sequelae in the neonatal period or years after birth. Schoolteachers and daycare personnel have an increased risk of perinatal varicella, "fifth disease," and mumps. Perinatal listeriosis affects one in 20,000 births and may result in fetal wastage. Because of the risk of the possibility of vertical transmission, immunization during pregnancy with live virus vaccines is not recommended. PMID:8520961

  7. Arylthiosemicarbazones as antileishmanial agents.

    PubMed

    Manzano, José Ignacio; Cochet, Florent; Boucherle, Benjamin; Gómez-Pérez, Verónica; Boumendjel, Ahcène; Gamarro, Francisco; Peuchmaur, Marine

    2016-11-10

    Based on a screening process, we targeted substituted thiosemicarbazone as potential antileishmanial agents. Our objective was to identify the key structural elements contributing to the anti-parasite activity that might be used for development of effective drugs. A series of 32 compounds was synthesized and their efficacy was evaluated against the clinically relevant intracellular amastigotes of Leishmania donovani. From these, 22 compounds showed EC50 values below 10 μM with the most active derivative (compound 14) showing an EC50 of 0.8 μM with very low toxicity on two different mammalian cell lines. The most relevant structural elements required for higher activity indicate that the presence of a fused bicyclic aromatic ring such as a naphthalene bearing an alkyl or an alkoxy group substituent are prerequisites. Owing to the easy synthesis, high activity and low toxicity, the most active compounds could be considered as a lead for further development.

  8. Itch Management: Topical Agents.

    PubMed

    Metz, Martin; Staubach, Petra

    2016-01-01

    Chronic pruritus is a common problem in patients with inflammatory skin diseases as well as in subjects with dry or sensitive skin. Regardless of the underlying cause of the pruritus, a topical therapy is not only useful but most often necessary to achieve symptom control. A good topical therapy should fulfill different functions. An optimal basic therapy based on the condition of the skin is important to repair epithelial barrier defects and to rehydrate the skin. An adequate disease-specific topical therapy is crucial for inflamed skin, e.g. anti-inflammatory topical therapy is an important part in the treatment of atopic dermatitis. Finally, the use of specific antipruritic substances can help to improve pruritus in patients irrespective of the underlying disease. Here, we summarize topical agents used in the treatment of chronic pruritus. PMID:27578070

  9. [Ribonucleases as antiviral agents].

    PubMed

    Il'inskaia, O N; Shakh Makhmud, R

    2014-01-01

    Many ribonucleases (RNases) are able to inhibit the reproduction of viruses in infected cell cultures and laboratory animals, but molecular mechanisms of their antiviral activity remain unclear. The review observes the most known RNases which possess established antiviral effects, actually intracellular RNases (RNase L, MCPIPI protein, eosinophylic RNases) as well as exogenously applied ones (RNase A, BS-RNase, onconase, binase, synthetic RNases). Attention is given on two important but not always obligatory aspects in molecule of RNases, which have antiviral properties: catalytic activity and ability to the dimerization. The hypothetic scheme of virus elimination by exogenous RNases, that reflects possible types of interaction of viruses and RNases with a cell, is proposed. The evidence for RNases as classical components of immune defense which are perspective agents for development of new antiviral therapeutics is produced.

  10. Agent-based enterprise integration

    SciTech Connect

    N. M. Berry; C. M. Pancerella

    1998-12-01

    The authors are developing and deploying software agents in an enterprise information architecture such that the agents manage enterprise resources and facilitate user interaction with these resources. The enterprise agents are built on top of a robust software architecture for data exchange and tool integration across heterogeneous hardware and software. The resulting distributed multi-agent system serves as a method of enhancing enterprises in the following ways: providing users with knowledge about enterprise resources and applications; accessing the dynamically changing enterprise; locating enterprise applications and services; and improving search capabilities for applications and data. Furthermore, agents can access non-agents (i.e., databases and tools) through the enterprise framework. The ultimate target of the effort is the user; they are attempting to increase user productivity in the enterprise. This paper describes their design and early implementation and discusses the planned future work.

  11. Collaborating Fuzzy Reinforcement Learning Agents

    NASA Technical Reports Server (NTRS)

    Berenji, Hamid R.

    1997-01-01

    Earlier, we introduced GARIC-Q, a new method for doing incremental Dynamic Programming using a society of intelligent agents which are controlled at the top level by Fuzzy Relearning and at the local level, each agent learns and operates based on ANTARCTIC, a technique for fuzzy reinforcement learning. In this paper, we show that it is possible for these agents to compete in order to affect the selected control policy but at the same time, they can collaborate while investigating the state space. In this model, the evaluator or the critic learns by observing all the agents behaviors but the control policy changes only based on the behavior of the winning agent also known as the super agent.

  12. [Contact sensitization to external agents].

    PubMed

    Erdmann, S M; Merk, H-F

    2003-04-01

    The following review describes contact sensitization to topically applied medications--especially topical dermatological agents--and to external agents in the broadest sense. Particularly skin care products constitute a special source for sensitization due to their widespread use. Especially fragrances and preservatives in cosmetics play an important global role in eliciting contact allergies. Because of the extremely broad spectrum covered by the active and adjuvant ingredients contained in external agents, the following discussion focuses on specific substance groups.

  13. Problems of Glioblastoma Multiforme Drug Resistance.

    PubMed

    Stavrovskaya, A A; Shushanov, S S; Rybalkina, E Yu

    2016-02-01

    Glioblastoma multiforme (GBL) is the most common and aggressive brain neoplasm. A standard therapeutic approach for GBL involves combination therapy consisting of surgery, radiotherapy, and chemotherapy. The latter is based on temozolomide (TMZ). However, even by applying such a radical treatment strategy, the mean patient survival time is only 14.6 months. Here we review the molecular mechanisms underlying the resistance of GBL cells to TMZ including genetic and epigenetic mechanisms. Present data regarding a role for genes and proteins MGMT, IDH1/2, YB-1, MELK, MVP/LRP, MDR1 (ABCB1), and genes encoding other ABC transporters as well as Akt3 kinase in developing resistance of GBL to TMZ are discussed. Some epigenetic regulators of resistance to TMZ such as microRNA and EZH2 are reviewed. PMID:27260389

  14. Broad-spectrum antiviral agents

    PubMed Central

    Zhu, Jun-Da; Meng, Wen; Wang, Xiao-Jia; Wang, Hwa-Chain R.

    2015-01-01

    Development of highly effective, broad-spectrum antiviral agents is the major objective shared by the fields of virology and pharmaceutics. Antiviral drug development has focused on targeting viral entry and replication, as well as modulating cellular defense system. High throughput screening of molecules, genetic engineering of peptides, and functional screening of agents have identified promising candidates for development of optimal broad-spectrum antiviral agents to intervene in viral infection and control viral epidemics. This review discusses current knowledge, prospective applications, opportunities, and challenges in the development of broad-spectrum antiviral agents. PMID:26052325

  15. Incorporating BDI Agents into Human-Agent Decision Making Research

    NASA Astrophysics Data System (ADS)

    Kamphorst, Bart; van Wissen, Arlette; Dignum, Virginia

    Artificial agents, people, institutes and societies all have the ability to make decisions. Decision making as a research area therefore involves a broad spectrum of sciences, ranging from Artificial Intelligence to economics to psychology. The Colored Trails (CT) framework is designed to aid researchers in all fields in examining decision making processes. It is developed both to study interaction between multiple actors (humans or software agents) in a dynamic environment, and to study and model the decision making of these actors. However, agents in the current implementation of CT lack the explanatory power to help understand the reasoning processes involved in decision making. The BDI paradigm that has been proposed in the agent research area to describe rational agents, enables the specification of agents that reason in abstract concepts such as beliefs, goals, plans and events. In this paper, we present CTAPL: an extension to CT that allows BDI software agents that are written in the practical agent programming language 2APL to reason about and interact with a CT environment.

  16. Phytonutrients as therapeutic agents.

    PubMed

    Gupta, Charu; Prakash, Dhan

    2014-09-01

    Nutrients present in various foods plays an important role in maintaining the normal functions of the human body. The major nutrients present in foods include carbohydrates, proteins, lipids, vitamins, and minerals. Besides these, there are some bioactive food components known as "phytonutrients" that play an important role in human health. They have tremendous impact on the health care system and may provide medical health benefits including the prevention and/or treatment of disease and various physiological disorders. Phytonutrients play a positive role by maintaining and modulating immune function to prevent specific diseases. Being natural products, they hold a great promise in clinical therapy as they possess no side effects that are usually associated with chemotherapy or radiotherapy. They are also comparatively cheap and thus significantly reduce health care cost. Phytonutrients are the plant nutrients with specific biological activities that support human health. Some of the important bioactive phytonutrients include polyphenols, terpenoids, resveratrol, flavonoids, isoflavonoids, carotenoids, limonoids, glucosinolates, phytoestrogens, phytosterols, anthocyanins, ω-3 fatty acids, and probiotics. They play specific pharmacological effects in human health such as anti-microbial, anti-oxidants, anti-inflammatory, antiallergic, anti-spasmodic, anti-cancer, anti-aging, hepatoprotective, hypolipidemic, neuroprotective, hypotensive, diabetes, osteoporosis, CNS stimulant, analgesic, protection from UVB-induced carcinogenesis, immuno-modulator, and carminative. This mini-review attempts to summarize the major important types of phytonutrients and their role in promoting human health and as therapeutic agents along with the current market trend and commercialization.

  17. Plasmids encoding therapeutic agents

    DOEpatents

    Keener, William K.

    2007-08-07

    Plasmids encoding anti-HIV and anti-anthrax therapeutic agents are disclosed. Plasmid pWKK-500 encodes a fusion protein containing DP178 as a targeting moiety, the ricin A chain, an HIV protease cleavable linker, and a truncated ricin B chain. N-terminal extensions of the fusion protein include the maltose binding protein and a Factor Xa protease site. C-terminal extensions include a hydrophobic linker, an L domain motif peptide, a KDEL ER retention signal, another Factor Xa protease site, an out-of-frame buforin II coding sequence, the lacZ.alpha. peptide, and a polyhistidine tag. More than twenty derivatives of plasmid pWKK-500 are described. Plasmids pWKK-700 and pWKK-800 are similar to pWKK-500 wherein the DP178-encoding sequence is substituted by RANTES- and SDF-1-encoding sequences, respectively. Plasmid pWKK-900 is similar to pWKK-500 wherein the HIV protease cleavable linker is substituted by a lethal factor (LF) peptide-cleavable linker.

  18. TACtic- A Multi Behavioral Agent for Trading Agent Competition

    NASA Astrophysics Data System (ADS)

    Khosravi, Hassan; Shiri, Mohammad E.; Khosravi, Hamid; Iranmanesh, Ehsan; Davoodi, Alireza

    Software agents are increasingly being used to represent humans in online auctions. Such agents have the advantages of being able to systematically monitor a wide variety of auctions and then make rapid decisions about what bids to place in what auctions. They can do this continuously and repetitively without losing concentration. To provide a means of evaluating and comparing (benchmarking) research methods in this area the trading agent competition (TAC) was established. This paper describes the design, of TACtic. Our agent uses multi behavioral techniques at the heart of its decision making to make bidding decisions in the face of uncertainty, to make predictions about the likely outcomes of auctions, and to alter the agent's bidding strategy in response to the prevailing market conditions.

  19. Hypersensitivity to antineoplastic agents.

    PubMed

    Castells, M C

    2008-01-01

    The need to offer first line therapy for primary and recurrent cancers has spurred the clinical development of rapid desensitizations for chemotherapy and monoclonal antibodies. Rapid desensitizations allow patients to be treated with medications to which they have presented with hypersensitivity reactions (HSRs), including anaphylaxis. Rapid desensitization achieves temporary tolerization to full therapeutic doses by slow administration of incremental doses of the drug inducing the HSR. Protocols are available for most chemotherapy agents, including taxanes, platins, doxorubicin, monoclonal antibodies, and others. Candidate patients include those who present with type I HSRs, mast cell/IgE dependent, including anaphylaxis, and non-IgE mediated HSRs, during the chemotherapy infusion or shortly after. Idiosyncratic reactions, erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis are not amenable to rapid desensitization. The recommendation for rapid desensitization can only be made by allergy and immunology specialists and can only be performed in settings with one-to-one nurse-patient care and where resuscitation personnel and resources are readily available. Repeated desensitizations can be safely performed in outpatient settings with similar conditions, which allow cancer patients to remain in clinical studies. We have generated a universal 12-step protocol that was applied to 413 cases of intravenous and intraperitoneal rapid desensitizations using taxanes, platins, liposomal doxorubicin, doxorubicin, rituximab, and other chemotherapy drugs. Under this protocol all patients were able to complete their target dose, and 94% of the patients had limited or no reactions. No deaths or codes were reported, indicating that the procedure was safe and effective in delivering first line chemotherapy drugs. PMID:18991707

  20. Agent-Based Literacy Theory

    ERIC Educational Resources Information Center

    McEneaney, John E.

    2006-01-01

    The purpose of this theoretical essay is to explore the limits of traditional conceptualizations of reader and text and to propose a more general theory based on the concept of a literacy agent. The proposed theoretical perspective subsumes concepts from traditional theory and aims to account for literacy online. The agent-based literacy theory…

  1. Gelled Anti-icing Agents

    NASA Technical Reports Server (NTRS)

    Markles, O. F.; Sperber, H. H.

    1983-01-01

    Pectin added to antifreeze/water mixture. Formulations include water with dimethyl sulfoxide (DMSO) as deicer and pectin as gel former. Without gelling agent, deicer runs off vertical surfaces. Without pectin solution will completely evaporate in far less time. Agents developed have wide potential for ice prevention on runways, highways, bridges and sidewalks.

  2. Dialogue Games for Agent Argumentation

    NASA Astrophysics Data System (ADS)

    McBurney, Peter; Parsons, Simon

    The rise of the Internet and the growth of distributed computing have led to a major paradigm shift in software engineering and computer science. Until recently, the notion of computation has been variously construed as numerical calculation, as information processing, or as intelligent symbol analysis, but increasingly, it is now viewed as distributed cognition and interaction between intelligent entities [60]. This new view has major implications for the conceptualization, design, engineering and control of software systems, most profoundly expressed in the concept of systems of intelligent software agents, or multi-agent systems [99]. Agents are software entities with control over their own execution; the design of such agents, and of multi-agent systems of them, presents major research and software engineering challenges to computer scientists.

  3. Intelligent Agents in Physics Education

    NASA Astrophysics Data System (ADS)

    Sánchez-Guzmán, D.; Mora, César

    2010-07-01

    Intelligent Agents are being applied in a wide range of processes and everyday applications. Their development is not new, in recent years they have had an increased attention and design; like learning and mentoring tools. In this work we discuss the definition of what an intelligent agent is; how they are applied; how they look like; recent implementations of agents; agents as support in the learning process, more precisely intelligent tutors; their state in Latin-American countries and future developments and trends that will permit a better communication between people and agents. Also we present an Intelligent Tutor applied as a tool for improving high-school students' skills and reasoning for the first five topics of Mechanics curricula.

  4. Transdermal delivery of therapeutic agent

    NASA Technical Reports Server (NTRS)

    Kwiatkowski, Krzysztof C. (Inventor); Hayes, Ryan T. (Inventor); Magnuson, James W. (Inventor); Giletto, Anthony (Inventor)

    2008-01-01

    A device for the transdermal delivery of a therapeutic agent to a biological subject that includes a first electrode comprising a first array of electrically conductive microprojections for providing electrical communication through a skin portion of the subject to a second electrode comprising a second array of electrically conductive microprojections. Additionally, a reservoir for holding the therapeutic agent surrounding the first electrode and a pulse generator for providing an exponential decay pulse between the first and second electrodes may be provided. A method includes the steps of piercing a stratum corneum layer of skin with two arrays of conductive microprojections, encapsulating the therapeutic agent into biocompatible charged carriers, surrounding the conductive microprojections with the therapeutic agent, generating an exponential decay pulse between the two arrays of conductive microprojections to create a non-uniform electrical field and electrokinetically driving the therapeutic agent through the stratum corneum layer of skin.

  5. Markov Tracking for Agent Coordination

    NASA Technical Reports Server (NTRS)

    Washington, Richard; Lau, Sonie (Technical Monitor)

    1998-01-01

    Partially observable Markov decision processes (POMDPs) axe an attractive representation for representing agent behavior, since they capture uncertainty in both the agent's state and its actions. However, finding an optimal policy for POMDPs in general is computationally difficult. In this paper we present Markov Tracking, a restricted problem of coordinating actions with an agent or process represented as a POMDP Because the actions coordinate with the agent rather than influence its behavior, the optimal solution to this problem can be computed locally and quickly. We also demonstrate the use of the technique on sequential POMDPs, which can be used to model a behavior that follows a linear, acyclic trajectory through a series of states. By imposing a "windowing" restriction that restricts the number of possible alternatives considered at any moment to a fixed size, a coordinating action can be calculated in constant time, making this amenable to coordination with complex agents.

  6. Knowledge focus via software agents

    NASA Astrophysics Data System (ADS)

    Henager, Donald E.

    2001-09-01

    The essence of military Command and Control (C2) is making knowledge intensive decisions in a limited amount of time using uncertain, incorrect, or outdated information. It is essential to provide tools to decision-makers that provide: * Management of friendly forces by treating the "friendly resources as a system". * Rapid assessment of effects of military actions againt the "enemy as a system". * Assessment of how an enemy should, can, and could react to friendly military activities. Software agents in the form of mission agents, target agents, maintenance agents, and logistics agents can meet this information challenge. The role of each agent is to know all the details about its assigned mission, target, maintenance, or logistics entity. The Mission Agent would fight for mission resources based on the mission priority and analyze the effect that a proposed mission's results would have on the enemy. The Target Agent (TA) communicates with other targets to determine its role in the system of targets. A system of TAs would be able to inform a planner or analyst of the status of a system of targets, the effect of that status, adn the effect of attacks on that system. The system of TAs would also be able to analyze possible enemy reactions to attack by determining ways to minimize the effect of attack, such as rerouting traffic or using deception. The Maintenance Agent would scheudle maintenance events and notify the maintenance unit. The Logistics Agent would manage shipment and delivery of supplies to maintain appropriate levels of weapons, fuel and spare parts. The central idea underlying this case of software agents is knowledge focus. Software agents are createad automatically to focus their attention on individual real-world entities (e.g., missions, targets) and view the world from that entities perspective. The agent autonomously monitors the entity, identifies problems/opportunities, formulates solutions, and informs the decision-maker. The agent must be

  7. MicroRNA-138 promotes acquired alkylator resistance in glioblastoma by targeting the Bcl-2-interacting mediator BIM

    PubMed Central

    Stojcheva, Nina; Schechtmann, Gennadi; Sass, Steffen; Roth, Patrick; Florea, Ana-Maria; Stefanski, Anja; Stühler, Kai; Wolter, Marietta; Müller, Nikola S.; Theis, Fabian J.; Weller, Michael; Reifenberger, Guido; Happold, Caroline

    2016-01-01

    Glioblastoma is the most aggressive brain tumor in adults with a median survival below 12 months in population-based studies. The main reason for tumor recurrence and progression is constitutive or acquired resistance to the standard of care of surgical resection followed by radiotherapy with concomitant and adjuvant temozolomide (TMZ/RT→TMZ). Here, we investigated the role of microRNA (miRNA) alterations as mediators of alkylator resistance in glioblastoma cells. Using microarray-based miRNA expression profiling of parental and TMZ-resistant cultures of three human glioma cell lines, we identified a set of differentially expressed miRNA candidates. From these, we selected miR-138 for further functional analyses as this miRNA was not only upregulated in TMZ-resistant versus parental cells, but also showed increased expression in vivo in recurrent glioblastoma tissue samples after TMZ/RT→TMZ treatment. Transient transfection of miR-138 mimics in glioma cells with low basal miR-138 expression increased glioma cell proliferation. Moreover, miR-138 overexpression increased TMZ resistance in long-term glioblastoma cell lines and glioma initiating cell cultures. The apoptosis regulator BIM was identified as a direct target of miR-138, and its silencing mediated the induced TMZ resistance phenotype. Altered sensitivity to apoptosis played only a minor role in this resistance mechanism. Instead, we identified the induction of autophagy to be regulated downstream of the miR-138/BIM axis and to promote cell survival following TMZ exposure. Our data thus define miR-138 as a glioblastoma cell survival-promoting miRNA associated with resistance to TMZ therapy in vitro and with tumor progression in vivo. PMID:26887050

  8. Contrast agents for cardiac angiography: effects of a nonionic agent vs. a standard ionic agent

    SciTech Connect

    Bettmann, M.A.; Bourdillon, P.D.; Barry, W.H.; Brush, K.A.; Levin, D.C.

    1984-12-01

    The effects on cardiac hemodynamics and of a standard contrast agent, sodium methylglucamine diatrizoate (Renografin 76) were compared with the effects of a new nonionic agent (iohexol) in a double-blind study in 51 patietns undergoing coronary angiography and left ventriculography. No significant alteration in measured blood parameters occurred with either contrast agent. Hemodynamic changes occurred with both, but were significantly greater with the standard renografin than with the low-osmolality, nonionic iohexol. After left ventriculography, heart rate increased and peripheral arterial pressure fell with both agents, but less with iohexol. It is concluded that iohexol causes less alteration in cardiac function than does the agent currently most widely used. Nonionic contrast material is likely to improve the safety of coronary angiography, particularly in those patients at greatest risk.

  9. Agent Communications using Distributed Metaobjects

    SciTech Connect

    Goldsmith, Steven Y.; Spires, Shannon V.

    1999-06-10

    There are currently two proposed standards for agent communication languages, namely, KQML (Finin, Lobrou, and Mayfield 1994) and the FIPA ACL. Neither standard has yet achieved primacy, and neither has been evaluated extensively in an open environment such as the Internet. It seems prudent therefore to design a general-purpose agent communications facility for new agent architectures that is flexible yet provides an architecture that accepts many different specializations. In this paper we exhibit the salient features of an agent communications architecture based on distributed metaobjects. This architecture captures design commitments at a metaobject level, leaving the base-level design and implementation up to the agent developer. The scope of the metamodel is broad enough to accommodate many different communication protocols, interaction protocols, and knowledge sharing regimes through extensions to the metaobject framework. We conclude that with a powerful distributed object substrate that supports metaobject communications, a general framework can be developed that will effectively enable different approaches to agent communications in the same agent system. We have implemented a KQML-based communications protocol and have several special-purpose interaction protocols under development.

  10. Nuclear magnetic resonance contrast agents

    DOEpatents

    Smith, P.H.; Brainard, J.R.; Jarvinen, G.D.; Ryan, R.R.

    1997-12-30

    A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC{sub 16}H{sub 14}N{sub 6}. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques. 10 figs.

  11. Nuclear magnetic resonance contrast agents

    DOEpatents

    Smith, Paul H.; Brainard, James R.; Jarvinen, Gordon D.; Ryan, Robert R.

    1997-01-01

    A family of contrast agents for use in magnetic resonance imaging and a method of enhancing the contrast of magnetic resonance images of an object by incorporating a contrast agent of this invention into the object prior to forming the images or during formation of the images. A contrast agent of this invention is a paramagnetic lanthanide hexaazamacrocyclic molecule, where a basic example has the formula LnC.sub.16 H.sub.14 N.sub.6. Important applications of the invention are in medical diagnosis, treatment, and research, where images of portions of a human body are formed by means of magnetic resonance techniques.

  12. Antibacterial agents in the cinema.

    PubMed

    García Sánchez, J E; García Sánchez, E; Merino Marcos, M L

    2006-12-01

    Numerous procedures used as antibacterial therapy are present in many films and include strategies ranging from different antimicrobial drugs to surgery and supporting measures. Films also explore the correct use and misuse of antimicrobial agents. Side effects and other aspects related to antibacterial therapy have also been reflected in some films. This article refers to the presence of antibacterial agents in different popular movies. There are movies in which antibacterial agents form part of the central plot, while in others it is merely an important part of the plot. In still others, its presence is isolated, and in these it plays an ambient or anecdotal role.

  13. Provocative agents in panic disorder.

    PubMed

    Bourin, M; Malinge, M; Guitton, B

    1995-01-01

    The pharmacological challenge strategy involves giving a provoking agent under controlled rules to clarify some aspect of behavioural or biological function. Various agents such as sodium lactate, carbon dioxide, caffeine, yohimbine, isoprenaline and now cholecystokinin have been used as provoking agents in healthy volunteers as well as in panic patients. Results obtained in this field are updated, with emphasis on the potential mechanisms of action. It is concluded that there may be a final pathway between carbon dioxide, sodium lactate, and cholecystokinin inducing panic attacks.

  14. Agent-based forward analysis

    SciTech Connect

    Kerekes, Ryan A.; Jiao, Yu; Shankar, Mallikarjun; Potok, Thomas E.; Lusk, Rick M.

    2008-01-01

    We propose software agent-based "forward analysis" for efficient information retrieval in a network of sensing devices. In our approach, processing is pushed to the data at the edge of the network via intelligent software agents rather than pulling data to a central facility for processing. The agents are deployed with a specific query and perform varying levels of analysis of the data, communicating with each other and sending only relevant information back across the network. We demonstrate our concept in the context of face recognition using a wireless test bed comprised of PDA cell phones and laptops. We show that agent-based forward analysis can provide a significant increase in retrieval speed while decreasing bandwidth usage and information overload at the central facility. n

  15. Triggered pore-forming agents

    DOEpatents

    Bayley, Hagan; Walker, Barbara J.; Chang, Chung-yu; Niblack, Brett; Panchal, Rekha

    1998-01-01

    An inactive pore-forming agent which is activated to lytic function by a condition such as pH, light, heat, reducing potential, or metal ion concentration, or substance such as a protease, at the surface of a cell.

  16. AL Amyloidosis and Agent Orange

    MedlinePlus

    ... for survivors' benefits . Research on AL amyloidosis and herbicides The Health and Medicine Division (formally known as ... to the compounds of interest found in the herbicide Agent Orange and AL amyloidosis." VA made a ...

  17. Diamine curing agents for polyurethanes

    NASA Technical Reports Server (NTRS)

    Bell, V. L.; St. Clair, T. L.

    1975-01-01

    Three aromatic diamines have properties that make them promising candidates as curing agents for converting isocyanates to polyurethanes with higher adhesive strengths, higher softening temperatures, better toughness, and improved abrasion resistance.

  18. Launch Commit Criteria Monitoring Agent

    NASA Technical Reports Server (NTRS)

    Semmel, Glenn S.; Davis, Steven R.; Leucht, Kurt W.; Rowe, Dan A.; Kelly, Andrew O.; Boeloeni, Ladislau

    2005-01-01

    The Spaceport Processing Systems Branch at NASA Kennedy Space Center has developed and deployed a software agent to monitor the Space Shuttle's ground processing telemetry stream. The application, the Launch Commit Criteria Monitoring Agent, increases situational awareness for system and hardware engineers during Shuttle launch countdown. The agent provides autonomous monitoring of the telemetry stream, automatically alerts system engineers when predefined criteria have been met, identifies limit warnings and violations of launch commit criteria, aids Shuttle engineers through troubleshooting procedures, and provides additional insight to verify appropriate troubleshooting of problems by contractors. The agent has successfully detected launch commit criteria warnings and violations on a simulated playback data stream. Efficiency and safety are improved through increased automation.

  19. Noncontraceptive use of contraceptive agents.

    PubMed

    Nickles, Monique Collier; Alderman, Elizabeth

    2014-06-01

    • On the basis of strong research evidence, there are many noncontraceptive advantages to use of hormonal contraceptive agents in adolescent girls. (3) (4)(5)(7)(10)(11)(12)(13)(14). • On the basis of research evidence and consensus, most of these agents are safe with minor adverse effects. (2)(3)(4)(5)(7)(10)(11)(12)(13)(14). • On the basis of research evidence and consensus, through application of evidence-based approaches and proper counseling, pediatricians can use various contraceptive agents to treat several medical conditions and to help alleviate many of the undesired symptoms and complications associated with menstrual periods. (2)(3)(4)(5)(7)(10)(11)(12)(13) (14). • On the basis of research evidence and consensus, these agents may be used in sexually active adolescents to simultaneously help prevent unintended adolescent pregnancies. (2)(3)(4)(5)(7)(10)(11)(12)(13)(14).

  20. Antimicrobials for bacterial bioterrorism agents.

    PubMed

    Sarkar-Tyson, Mitali; Atkins, Helen S

    2011-06-01

    The limitations of current antimicrobials for highly virulent pathogens considered as potential bioterrorism agents drives the requirement for new antimicrobials that are suitable for use in populations in the event of a deliberate release. Strategies targeting bacterial virulence offer the potential for new countermeasures to combat bacterial bioterrorism agents, including those active against a broad spectrum of pathogens. Although early in the development of antivirulence approaches, inhibitors of bacterial type III secretion systems and cell division mechanisms show promise for the future.

  1. Ramucirumab: a novel antiangiogenic agent.

    PubMed

    Wadhwa, Roopma; Taketa, Takashi; Sudo, Kazuki; Blum-Murphy, Mariela; Ajani, Jaffer A

    2013-06-01

    Ramucirumab (IMC-1121B) is a fully humanized monoclonal antibody that binds to VEGFR2 and can inhibit angiogenesis, a quintessential mechanism for promoting tumor growth and metastasis. Several antiangiogenesis agents are already approved for cancer therapy; however, ramucirumab's selectivity for VEGFR2 makes it interesting. The selectivity of an agent can improve safety and efficacy. This article describes the mechanism of action, pharmacokinetics, safety and clinical trial results of ramucirumab with particular emphasis on gastric cancer.

  2. Natural products as antimitotic agents.

    PubMed

    Dall'Acqua, Stefano

    2014-01-01

    Natural products still play an important role in the medicinal chemistry, especially in some therapeutic areas. As example more than 60% of currently-used anticancer agents are derives from natural sources including plants, marine organisms or micro-organism. Thus natural products (NP) are an high-impact source of new "lead compounds" or new potential therapeutic agents despite the large development of biotechnology and combinatorial chemistry in the drug discovery and development. Many examples of anticancer drugs as paclitaxel, combretastatin, bryostatin and discodermolide have shown the importance of NP in the anticancer chemotherapy through many years. Many organisms have been studied as sources of drugs namely plants, micro-organisms and marine organisms and the obtained NP can be considered a group of "privileged chemical structures" evolved in nature to interact with other organisms. For this reason NP are a good starting points for pharmaceutical research and also for library design. Tubulin and microtubules are one of the most studied targets for the search of anticancer compounds. Microtubule targeting agents (MTA) also named antimitotic agents are compounds that are able to perturb mitosis but are also able to arrest cell growing during interphase. The anticancer drugs, taxanes and vinca alkaloids have established tubulin as important target in cancer therapy. More recently the vascular disrupting agents (VDA) combretastatin analogues were studied for their antimitotics properties. This review will consider the anti mitotic NP and their potential impact in the development of new therapeutic agents.

  3. What makes virtual agents believable?

    NASA Astrophysics Data System (ADS)

    Bogdanovych, Anton; Trescak, Tomas; Simoff, Simeon

    2016-01-01

    In this paper we investigate the concept of believability and make an attempt to isolate individual characteristics (features) that contribute to making virtual characters believable. As the result of this investigation we have produced a formalisation of believability and based on this formalisation built a computational framework focused on simulation of believable virtual agents that possess the identified features. In order to test whether the identified features are, in fact, responsible for agents being perceived as more believable, we have conducted a user study. In this study we tested user reactions towards the virtual characters that were created for a simulation of aboriginal inhabitants of a particular area of Sydney, Australia in 1770 A.D. The participants of our user study were exposed to short simulated scenes, in which virtual agents performed some behaviour in two different ways (while possessing a certain aspect of believability vs. not possessing it). The results of the study indicate that virtual agents that appear resource bounded, are aware of their environment, own interaction capabilities and their state in the world, agents that can adapt to changes in the environment and exist in correct social context are those that are being perceived as more believable. Further in the paper we discuss these and other believability features and provide a quantitative analysis of the level of contribution for each such feature to the overall perceived believability of a virtual agent.

  4. Trimetazidine and cardioprotection: facts and perspectives.

    PubMed

    Tsioufis, Konstantinos; Andrikopoulos, George; Manolis, Athanasios

    2015-03-01

    Trimetazidine (TMZ) is a metabolic agent used in cardiology for more than 40 years. Several studies assessed the cardioprotective effects of TMZ in patients with chronic coronary heart disease (CHD) as well as in patients with heart failure (HF). In light of the inclusion of TMZ in the current guidelines on the management of stable CHD, we reviewed the published literature on TMZ, focusing mainly its effects on patients with stable angina and HF. According to the published literature, there is sufficient evidence to support the addition of this agent in the treatment of symptomatic patients with stable angina. PMID:24719262

  5. A multi-agent architecture for geosimulation of moving agents

    NASA Astrophysics Data System (ADS)

    Vahidnia, Mohammad H.; Alesheikh, Ali A.; Alavipanah, Seyed Kazem

    2015-10-01

    In this paper, a novel architecture is proposed in which an axiomatic derivation system in the form of first-order logic facilitates declarative explanation and spatial reasoning. Simulation of environmental perception and interaction between autonomous agents is designed with a geographic belief-desire-intention and a request-inform-query model. The architecture has a complementary quantitative component that supports collaborative planning based on the concept of equilibrium and game theory. This new architecture presents a departure from current best practices geographic agent-based modelling. Implementation tasks are discussed in some detail, as well as scenarios for fleet management and disaster management.

  6. Next Generation Remote Agent Planner

    NASA Technical Reports Server (NTRS)

    Jonsson, Ari K.; Muscettola, Nicola; Morris, Paul H.; Rajan, Kanna

    1999-01-01

    In May 1999, as part of a unique technology validation experiment onboard the Deep Space One spacecraft, the Remote Agent became the first complete autonomous spacecraft control architecture to run as flight software onboard an active spacecraft. As one of the three components of the architecture, the Remote Agent Planner had the task of laying out the course of action to be taken, which included activities such as turning, thrusting, data gathering, and communicating. Building on the successful approach developed for the Remote Agent Planner, the Next Generation Remote Agent Planner is a completely redesigned and reimplemented version of the planner. The new system provides all the key capabilities of the original planner, while adding functionality, improving performance and providing a modular and extendible implementation. The goal of this ongoing project is to develop a system that provides both a basis for future applications and a framework for further research in the area of autonomous planning for spacecraft. In this article, we present an introductory overview of the Next Generation Remote Agent Planner. We present a new and simplified definition of the planning problem, describe the basics of the planning process, lay out the new system design and examine the functionality of the core reasoning module.

  7. Investigational Antimicrobial Agents of 2013

    PubMed Central

    Pucci, Michael J.

    2013-01-01

    SUMMARY New antimicrobial agents are always needed to counteract the resistant pathogens that continue to be selected by current therapeutic regimens. This review provides a survey of known antimicrobial agents that were currently in clinical development in the fall of 2012 and spring of 2013. Data were collected from published literature primarily from 2010 to 2012, meeting abstracts (2011 to 2012), government websites, and company websites when appropriate. Compared to what was reported in previous surveys, a surprising number of new agents are currently in company pipelines, particularly in phase 3 clinical development. Familiar antibacterial classes of the quinolones, tetracyclines, oxazolidinones, glycopeptides, and cephalosporins are represented by entities with enhanced antimicrobial or pharmacological properties. More importantly, compounds of novel chemical structures targeting bacterial pathways not previously exploited are under development. Some of the most promising compounds include novel β-lactamase inhibitor combinations that target many multidrug-resistant Gram-negative bacteria, a critical medical need. Although new antimicrobial agents will continue to be needed to address increasing antibiotic resistance, there are novel agents in development to tackle at least some of the more worrisome pathogens in the current nosocomial setting. PMID:24092856

  8. Relational agents in clinical psychiatry.

    PubMed

    Bickmore, Timothy; Gruber, Amanda

    2010-01-01

    Relational agents are computational artifacts, such as animated, screen-based characters or social robots, that are designed to establish a sense of rapport, trust, and even therapeutic alliance with patients, using ideal therapeutic relationships between human counselors and patients as role models. We describe the development and evaluation of several such agents designed for health counseling and behavioral-change interventions, in which a therapeutic alliance is established with patients in order to enhance the efficacy of the intervention. We also discuss the promise of using such agents as adjuncts to clinical psychiatry, a range of possible applications, and some of the challenges and ethical issues in developing and fielding them in psychiatric interventions.

  9. Haloprogin: a Topical Antifungal Agent

    PubMed Central

    Harrison, E. F.; Zwadyk, P.; Bequette, R. J.; Hamlow, E. E.; Tavormina, P. A.; Zygmunt, W. A.

    1970-01-01

    Haloprogin was shown to be a highly effective agent for the treatment of experimentally induced topical mycotic infections in guinea pigs. Its in vitro spectrum of activity also includes yeasts, yeastlike fungi (Candida species), and certain gram-positive bacteria. The in vitro and in vivo antifungal activity of haloprogin against dermatophytes was equal to that observed with tolnaftate. The striking differences between the two agents were the marked antimonilial and selective antibacterial activities shown by haloprogin, contrasted with the negligible activities found with tolnaftate. Addition of serum decreased the in vitro antifungal activity of haloprogin to a greater extent than that of tolnaftate; however, diminished antifungal activity was not observed when haloprogin was applied topically to experimental dermatophytic infections. Based on its broad spectrum of antimicrobial activity, haloprogin may prove to be a superior topical agent in the treatment of dermatophytic and monilial infections in man. PMID:5422306

  10. Dual Rationality and Deliberative Agents

    NASA Astrophysics Data System (ADS)

    Debenham, John; Sierra, Carles

    Human agents deliberate using models based on reason for only a minute proportion of the decisions that they make. In stark contrast, the deliberation of artificial agents is heavily dominated by formal models based on reason such as game theory, decision theory and logic—despite that fact that formal reasoning will not necessarily lead to superior real-world decisions. Further the Nobel Laureate Friedrich Hayek warns us of the ‘fatal conceit’ in controlling deliberative systems using models based on reason as the particular model chosen will then shape the system’s future and either impede, or eventually destroy, the subtle evolutionary processes that are an integral part of human systems and institutions, and are crucial to their evolution and long-term survival. We describe an architecture for artificial agents that is founded on Hayek’s two rationalities and supports the two forms of deliberation used by mankind.

  11. Polycatechol Nanoparticle MRI Contrast Agents.

    PubMed

    Li, Yiwen; Huang, Yuran; Wang, Zhao; Carniato, Fabio; Xie, Yijun; Patterson, Joseph P; Thompson, Matthew P; Andolina, Christopher M; Ditri, Treffly B; Millstone, Jill E; Figueroa, Joshua S; Rinehart, Jeffrey D; Scadeng, Miriam; Botta, Mauro; Gianneschi, Nathan C

    2016-02-01

    Amphiphilic triblock copolymers containing Fe(III) -catecholate complexes formulated as spherical- or cylindrical-shaped micellar nanoparticles (SMN and CMN, respectively) are described as new T1-weighted agents with high relaxivity, low cytotoxicity, and long-term stability in biological fluids. Relaxivities of both SMN and CMN exceed those of established gadolinium chelates across a wide range of magnetic field strengths. Interestingly, shape-dependent behavior is observed in terms of the particles' interactions with HeLa cells, with CMN exhibiting enhanced uptake and contrast via magnetic resonance imaging (MRI) compared with SMN. These results suggest that control over soft nanoparticle shape will provide an avenue for optimization of particle-based contrast agents as biodiagnostics. The polycatechol nanoparticles are proposed as suitable for preclinical investigations into their viability as gadolinium-free, safe, and effective imaging agents for MRI contrast enhancement. PMID:26681255

  12. Agent review phase one report.

    SciTech Connect

    Zubelewicz, Alex Tadeusz; Davis, Christopher Edward; Bauer, Travis LaDell

    2009-12-01

    This report summarizes the findings for phase one of the agent review and discusses the review methods and results. The phase one review identified a short list of agent systems that would prove most useful in the service architecture of an information management, analysis, and retrieval system. Reviewers evaluated open-source and commercial multi-agent systems and scored them based upon viability, uniqueness, ease of development, ease of deployment, and ease of integration with other products. Based on these criteria, reviewers identified the ten most appropriate systems. The report also mentions several systems that reviewers deemed noteworthy for the ideas they implement, even if those systems are not the best choices for information management purposes.

  13. Polymeric drug delivery for the treatment of glioblastoma

    PubMed Central

    Wait, Scott D.; Prabhu, Roshan S.; Burri, Stuart H.; Atkins, Tyler G.; Asher, Anthony L.

    2015-01-01

    Glioblastoma (GBM) remains an almost universally fatal diagnosis. The current therapeutic mainstay consists of maximal safe surgical resection followed by radiation therapy (RT) with concomitant temozolomide (TMZ), followed by monthly TMZ (the “Stupp regimen”). Several chemotherapeutic agents have been shown to have modest efficacy in the treatment of high-grade glioma (HGG), but blood-brain barrier impermeability remains a major delivery obstacle. Polymeric drug-delivery systems, developed to allow controlled local release of biologically active substances for a variety of conditions, can achieve high local concentrations of active agents while limiting systemic toxicities. Polymerically delivered carmustine (BCNU) wafers, placed on the surface of the tumor-resection cavity, can potentially provide immediate chemotherapy to residual tumor cells during the standard delay between surgery and chemoradiotherapy. BCNU wafer implantation as monochemotherapy (with RT) in newly diagnosed HGG has been investigated in 2 phase III studies that reported significant increases in median overall survival. A number of studies have investigated the tumoricidal synergies of combination chemotherapy with BCNU wafers in newly diagnosed or recurrent HGG, and a primary research focus has been the integration of BCNU wafers into multimodality therapy with the standard Stupp regimen. Overall, the results of these studies have been encouraging in terms of safety and efficacy. However, the data must be qualified by the nature of the studies conducted. Currently, there are no phase III studies of BCNU wafers with the standard Stupp regimen. We review the rationale, biochemistry, pharmacokinetics, and research history (including toxicity profile) of this modality. PMID:25746091

  14. Economics of Malignant Gliomas: A Critical Review

    PubMed Central

    Raizer, Jeffrey J.; Fitzner, Karen A.; Jacobs, Daniel I.; Bennett, Charles L.; Liebling, Dustin B.; Luu, Thanh Ha; Trifilio, Steven M.; Grimm, Sean A.; Fisher, Matthew J.; Haleem, Meraaj S.; Ray, Paul S.; McKoy, Judith M.; DeBoer, Rebecca; Tulas, Katrina-Marie E.; Deeb, Mohammed; McKoy, June M.

    2015-01-01

    Purpose: Approximately 18,500 persons are diagnosed with malignant glioma in the United States annually. Few studies have investigated the comprehensive economic costs. We reviewed the literature to examine costs to patients with malignant glioma and their families, payers, and society. Methods: A total of 18 fully extracted studies were included. Data were collected on direct and indirect costs, and cost estimates were converted to US dollars using the conversion rate calculated from the study's publication date, and updated to 2011 values after adjustment for inflation. A standardized data abstraction form was used. Data were extracted by one reviewer and checked by another. Results: Before approval of effective chemotherapeutic agents for malignant gliomas, estimated total direct medical costs in the United States for surgery and radiation therapy per patient ranged from $50,600 to $92,700. The addition of temozolomide (TMZ) and bevacizumab to glioblastoma treatment regimens has resulted in increased overall costs for glioma care. Although health care costs are now less front-loaded, they have increased over the course of illness. Analysis using a willingness-to-pay threshold of $50,000 per quality-adjusted life-year suggests that the benefits of TMZ fall on the edge of acceptable therapies. Furthermore, indirect medical costs, such as productivity losses, are not trivial. Conclusion: With increased chemotherapy use for malignant glioma, the paradigm for treatment and associated out-of-pocket and total medical costs continue to evolve. Larger out-of-pocket costs may influence the choice of chemotherapeutic agents, the economic implications of which should be evaluated prospectively. PMID:25466707

  15. Haematological toxicity of Valproic acid compared to Levetiracetam in patients with glioblastoma multiforme undergoing concomitant radio-chemotherapy: a retrospective cohort study.

    PubMed

    Tinchon, Alexander; Oberndorfer, Stefan; Marosi, Christine; Gleiss, Andreas; Geroldinger, Angelika; Sax, Cornelia; Sherif, Camillo; Moser, Walter; Grisold, Wolfgang

    2015-01-01

    Patients with glioblastoma multiforme (GBM) and symptomatic seizures are in need of a sufficient antiepileptic treatment. Haematological toxicity is a limiting side effect of both, first line radio-chemotherapy with temozolomide (TMZ) and co-medication with antiepileptic drugs. Valproic acid (VPA) and levetiracetam (LEV) are considered favourable agents in brain tumor patients with seizures, but are commonly reported to induce haematological side effects on their own. We hypothesized, that antiepileptic treatment with these agents has no increased impact on haematological side effects during radio-chemotherapy in the first line setting. We included 104 patients from two neuro-oncologic centres with GBM and standard radio-chemotherapy in a retrospective cohort study. Patients were divided according to their antiepileptic treatment with either VPA, LEV or without antiepileptic drug therapy (control group). Declines in haemoglobin levels and absolute blood cell counts for neutrophil granulocytes, lymphocytes and thrombocytes were analyzed twice during concomitant and once during adjuvant phase. A comparison between the examined groups was performed, using a linear mixed model. Neutrophil granulocytes, lymphocytes and thrombocytes significantly decreased over time in all three groups (all p < 0.012), but there was no significant difference between the compared groups. A significant decline in haemoglobin was observed in the LEV treated group (p = 0.044), but did not differ between the compared groups. As a novel finding, this study demonstrates that co-medication either with VPA or LEV in GBM patients undergoing first line radio-chemotherapy with TMZ has no additional impact on medium-term haematological toxicity.

  16. Thyroid Dysfunction from Antineoplastic Agents

    PubMed Central

    Larsen, P. Reed; Marqusee, Ellen

    2011-01-01

    Unlike cytotoxic agents that indiscriminately affect rapidly dividing cells, newer antineoplastic agents such as targeted therapies and immunotherapies are associated with thyroid dysfunction. These include tyrosine kinase inhibitors, bexarotene, radioiodine-based cancer therapies, denileukin diftitox, alemtuzumab, interferon-α, interleukin-2, ipilimumab, tremelimumab, thalidomide, and lenalidomide. Primary hypothyroidism is the most common side effect, although thyrotoxicosis and effects on thyroid-stimulating hormone secretion and thyroid hormone metabolism have also been described. Most agents cause thyroid dysfunction in 20%–50% of patients, although some have even higher rates. Despite this, physicians may overlook drug-induced thyroid dysfunction because of the complexity of the clinical picture in the cancer patient. Symptoms of hypothyroidism, such as fatigue, weakness, depression, memory loss, cold intolerance, and cardiovascular effects, may be incorrectly attributed to the primary disease or to the antineoplastic agent. Underdiagnosis of thyroid dysfunction can have important consequences for cancer patient management. At a minimum, the symptoms will adversely affect the patient’s quality of life. Alternatively, such symptoms can lead to dose reductions of potentially life-saving therapies. Hypothyroidism can also alter the kinetics and clearance of medications, which may lead to undesirable side effects. Thyrotoxicosis can be mistaken for sepsis or a nonendocrinologic drug side effect. In some patients, thyroid disease may indicate a higher likelihood of tumor response to the agent. Both hypothyroidism and thyrotoxicosis are easily diagnosed with inexpensive and specific tests. In many patients, particularly those with hypothyroidism, the treatment is straightforward. We therefore recommend routine testing for thyroid abnormalities in patients receiving these antineoplastic agents. PMID:22010182

  17. Thyroid dysfunction from antineoplastic agents.

    PubMed

    Hamnvik, Ole-Petter Riksfjord; Larsen, P Reed; Marqusee, Ellen

    2011-11-01

    Unlike cytotoxic agents that indiscriminately affect rapidly dividing cells, newer antineoplastic agents such as targeted therapies and immunotherapies are associated with thyroid dysfunction. These include tyrosine kinase inhibitors, bexarotene, radioiodine-based cancer therapies, denileukin diftitox, alemtuzumab, interferon-α, interleukin-2, ipilimumab, tremelimumab, thalidomide, and lenalidomide. Primary hypothyroidism is the most common side effect, although thyrotoxicosis and effects on thyroid-stimulating hormone secretion and thyroid hormone metabolism have also been described. Most agents cause thyroid dysfunction in 20%-50% of patients, although some have even higher rates. Despite this, physicians may overlook drug-induced thyroid dysfunction because of the complexity of the clinical picture in the cancer patient. Symptoms of hypothyroidism, such as fatigue, weakness, depression, memory loss, cold intolerance, and cardiovascular effects, may be incorrectly attributed to the primary disease or to the antineoplastic agent. Underdiagnosis of thyroid dysfunction can have important consequences for cancer patient management. At a minimum, the symptoms will adversely affect the patient's quality of life. Alternatively, such symptoms can lead to dose reductions of potentially life-saving therapies. Hypothyroidism can also alter the kinetics and clearance of medications, which may lead to undesirable side effects. Thyrotoxicosis can be mistaken for sepsis or a nonendocrinologic drug side effect. In some patients, thyroid disease may indicate a higher likelihood of tumor response to the agent. Both hypothyroidism and thyrotoxicosis are easily diagnosed with inexpensive and specific tests. In many patients, particularly those with hypothyroidism, the treatment is straightforward. We therefore recommend routine testing for thyroid abnormalities in patients receiving these antineoplastic agents. PMID:22010182

  18. Autonomous sensor manager agents (ASMA)

    NASA Astrophysics Data System (ADS)

    Osadciw, Lisa A.

    2004-04-01

    Autonomous sensor manager agents are presented as an algorithm to perform sensor management within a multisensor fusion network. The design of the hybrid ant system/particle swarm agents is described in detail with some insight into their performance. Although the algorithm is designed for the general sensor management problem, a simulation example involving 2 radar systems is presented. Algorithmic parameters are determined by the size of the region covered by the sensor network, the number of sensors, and the number of parameters to be selected. With straight forward modifications, this algorithm can be adapted for most sensor management problems.

  19. Phase I trial with biomarker studies of vatalanib (PTK787) in patients with newly diagnosed glioblastoma treated with enzyme inducing anti-epileptic drugs and standard radiation and temozolomide.

    PubMed

    Gerstner, Elizabeth R; Eichler, April F; Plotkin, Scott R; Drappatz, Jan; Doyle, Colin L; Xu, Lei; Duda, Dan G; Wen, Patrick Y; Jain, Rakesh K; Batchelor, Tracy T

    2011-06-01

    Targeting angiogenesis in glioblastoma (GBM) may improve patient outcome by normalizing tumor vasculature and improving delivery of chemotherapeutics and oxygen. Consequently, concomitant administration of small molecule inhibitors of the VEGF pathway will likely have a positive impact on chemoradiation treatment outcome. We conducted a Phase I study of vatalanib, a small molecule inhibitor of VEGFR, PDGFR, and c-kit in patients with newly diagnosed GBM receiving radiation, temozolomide, and an enzyme-inducing anti-epileptic drug in order to determine the MTD of vatalanib in this patient population. We incorporated circulating biomarker and SNP analyses and pharmacokinetic studies. Nineteen patients were enrolled and the MTD was not reached at the time of study termination. Vatalanib was well tolerated with only 2 DLTs (thrombocytopenia and elevated transaminases). Other grade 3/4 toxicities included leukopenia, lymphopenia, neutropenia, and hand-foot syndrome. There were no wound-healing complications. Of the 13 patients evaluable for a radiographic response, 2 had a partial response and 9 had stable disease. Vatalanib significantly increased PlGF and sVEGFR1 in plasma circulation and decreased sVEGFR2 and sTie2. Plasma collagen IV increased significantly by day 50 of treatment. Vatalanib was well tolerated and this study demonstrates the safety of oral small molecule inhibitors in newly diagnosed GBM patients. Blood biomarkers may be useful as pharmacodynamic markers of response to anti-angiogenic therapies. PMID:20821342

  20. Exposure to toxic environmental agents.

    PubMed

    2013-10-01

    Reducing exposure to toxic environmental agents is a critical area of intervention for obstetricians, gynecologists, and other reproductive health care professionals. Patient exposure to toxic environmental chemicals and other stressors is ubiquitous, and preconception and prenatal exposure to toxic environmental agents can have a profound and lasting effect on reproductive health across the life course.Prenatal exposure to certain chemicals has been documented to increase the risk of cancer in childhood; adult male exposure to pesticides is linked to altered semen quality, sterility, and prostate cancer; and postnatal exposure to some pesticides can interfere with all developmental stages of reproductive function in adult females, including puberty, menstruation and ovulation, fertility and fecundity, and menopause. Many environmental factors harmful to reproductive health disproportionately affect vulnerable and underserved populations,which leaves some populations, including underserved women, more vulnerable to adverse reproductive health effects than other populations. The evidence that links exposure to toxic environmental agents and adverse reproductive and developmental health outcomes is sufficiently robust, and the American College of Obstetricians and Gynecologists and the American Society for Reproductive Medicine join leading scientists and other clinical practitioners in calling for timely action to identify and reduce exposure to toxic environmental agents while addressing the consequences of such exposure.

  1. Exposure to toxic environmental agents.

    PubMed

    2013-10-01

    : Reducing exposure to toxic environmental agents is a critical area of intervention for obstetricians, gynecologists, and other reproductive health care professionals. Patient exposure to toxic environmental chemicals and other stressors is ubiquitous, and preconception and prenatal exposure to toxic environmental agents can have a profound and lasting effect on reproductive health across the life course. Prenatal exposure to certain chemicals has been documented to increase the risk of cancer in childhood; adult male exposure to pesticides is linked to altered semen quality, sterility, and prostate cancer; and postnatal exposure to some pesticides can interfere with all developmental stages of reproductive function in adult females, including puberty, menstruation and ovulation, fertility and fecundity, and menopause. Many environmental factors harmful to reproductive health disproportionately affect vulnerable and underserved populations, which leaves some populations, including underserved women, more vulnerable to adverse reproductive health effects than other populations. The evidence that links exposure to toxic environmental agents and adverse reproductive and developmental health outcomes is sufficiently robust, and the American College of Obstetricians and Gynecologists and the American Society for Reproductive Medicine join leading scientists and other clinical practitioners in calling for timely action to identify and reduce exposure to toxic environmental agents while addressing the consequences of such exposure.

  2. Triggered pore-forming agents

    DOEpatents

    Bayley, H.; Walker, B.J.; Chang, C.Y.; Niblack, B.; Panchal, R.

    1998-07-07

    An inactive pore-forming agent is revealed which is activated to lytic function by a condition such as pH, light, heat, reducing potential, or metal ion concentration, or substance such as a protease, at the surface of a cell. 30 figs.

  3. 7 CFR 4290.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., DEPARTMENT OF AGRICULTURE RURAL BUSINESS INVESTMENT COMPANY (âRBICâ) PROGRAM Financial Assistance for RBICs (Leverage) Funding Leverage by Use of Guaranteed Trust Certificates (âtcsâ) § 4290.1620 Functions of agents... to: (i) Establish performance criteria for Poolers. (ii) Monitor and evaluate the financial...

  4. Direct Vasodilators and Sympatholytic Agents.

    PubMed

    McComb, Meghan N; Chao, James Y; Ng, Tien M H

    2016-01-01

    Direct vasodilators and sympatholytic agents were some of the first antihypertensive medications discovered and utilized in the past century. However, side effect profiles and the advent of newer antihypertensive drug classes have reduced the use of these agents in recent decades. Outcome data and large randomized trials supporting the efficacy of these medications are limited; however, in general the blood pressure-lowering effect of these agents has repeatedly been shown to be comparable to other more contemporary drug classes. Nevertheless, a landmark hypertension trial found a negative outcome with a doxazosin-based regimen compared to a chlorthalidone-based regimen, leading to the removal of α-1 adrenergic receptor blockers as first-line monotherapy from the hypertension guidelines. In contemporary practice, direct vasodilators and sympatholytic agents, particularly hydralazine and clonidine, are often utilized in refractory hypertension. Hydralazine and minoxidil may also be useful alternatives for patients with renal dysfunction, and both hydralazine and methyldopa are considered first line for the treatment of hypertension in pregnancy. Hydralazine has also found widespread use for the treatment of systolic heart failure in combination with isosorbide dinitrate (ISDN). The data to support use of this combination in African Americans with heart failure are particularly robust. Hydralazine with ISDN may also serve as an alternative for patients with an intolerance to angiotensin antagonists. Given these niche indications, vasodilators and sympatholytics are still useful in clinical practice; therefore, it is prudent to understand the existing data regarding efficacy and the safe use of these medications. PMID:26033778

  5. Nucleotide cleaving agents and method

    DOEpatents

    Que, Jr., Lawrence; Hanson, Richard S.; Schnaith, Leah M. T.

    2000-01-01

    The present invention provides a unique series of nucleotide cleaving agents and a method for cleaving a nucleotide sequence, whether single-stranded or double-stranded DNA or RNA, using and a cationic metal complex having at least one polydentate ligand to cleave the nucleotide sequence phosphate backbone to yield a hydroxyl end and a phosphate end.

  6. 7 CFR 4290.1620 - Functions of agents, including Central Registration Agent, Selling Agent and Fiscal Agent.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 15 2011-01-01 2011-01-01 false Functions of agents, including Central Registration..., DEPARTMENT OF AGRICULTURE RURAL BUSINESS INVESTMENT COMPANY (âRBICâ) PROGRAM Financial Assistance for RBICs (Leverage) Funding Leverage by Use of Guaranteed Trust Certificates (âtcsâ) § 4290.1620 Functions of...

  7. SEM: A Cultural Change Agent

    ERIC Educational Resources Information Center

    Barnes, Bradley; Bourke, Brian

    2015-01-01

    The authors advance the concept that institutional culture is a purposeful framework by which to view SEM's utility, particularly as a cultural change agent. Through the connection of seemingly independent functions of performance and behavior, implications emerge that deepen the understanding of the influence of culture on performance outcomes…

  8. Limonene and tetrahydrofurfuryl alcohol cleaning agent

    DOEpatents

    Bohnert, George W.; Carter, Richard D.; Hand, Thomas E.; Powers, Michael T.

    1996-05-07

    The present invention is a tetrahydrofurfuryl alcohol and limonene or terpineol cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

  9. Limonene and tetrahydrofurfuryl alcohol cleaning agent

    DOEpatents

    Bohnert, G.W.; Carter, R.D.; Hand, T.E.; Powers, M.T.

    1997-10-21

    The present invention is a tetrahydrofurfuryl alcohol and limonene cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

  10. Limonene and tetrahydrofurfurly alcohol cleaning agent

    DOEpatents

    Bohnert, George W.; Carter, Richard D.; Hand, Thomas E.; Powers, Michael T.

    1997-10-21

    The present invention is a tetrahydrofurfuryl alcohol and limonene cleaning agent and method for formulating and/or using the cleaning agent. This cleaning agent effectively removes both polar and nonpolar contaminants from various electrical and mechanical parts and is readily used without surfactants, thereby reducing the need for additional cleaning operations. The cleaning agent is warm water rinsable without the use of surfactants. The cleaning agent can be azeotropic, enhancing ease of use in cleaning operations and ease of recycling.

  11. Halide test agent replacement study

    SciTech Connect

    Banks, E.M.; Freeman, W.P.; Kovach, B.J.

    1995-02-01

    The intended phaseout of the chlorofluorocarbons (CFCs) from commercial use required the evaluation of substitute materials for the testing for leak paths through both individual adsorbers and installed adsorbent banks. The American Society of Mechanical Engineers (ASME) Committee on Nuclear Air and Gas Treatment (CONAGT) is in charge of maintaining the standards and codes specifying adsorbent leak test methods for the nuclear safety related air cleaning systems. The currently published standards and codes cite the use of R-11, R-12 and R-112 for leak path test agents. All of these compounds are CFCs. There are other agencies and organizations (USDOE, USDOD and USNRC) also specifying testing for leak paths or in some cases for special life tests using the above compounds. The CONAGT has recently developed criteria for the suitability evaluation of substitute test agents. On the basis of these criteria, several compounds were evaluated for their acceptability as adsorbent bed leak and life test agents. The ASME CONAGT Test Agent Qualification Criteria. The test agent qualification is based on the following parameters: (1) Similar retention times on activated carbons at the same concentration levels as one of the following: R-11, R-12, R-112 or R-112a. (2) Similar lower detection limit sensitivity and precision in the concentration range of use as R-11, R-12, R-112 and R-112a. (3) Gives the same in-place leak test results as R-11, R-12, R-112, or R-112a. (4) Chemical and radiological stability under the use conditions. (5) Causes no degradation of the carbon and its impregnant or of the other NATS components under the use conditions. (6) Is listed in the USEPA Toxic Substances Control Act (TSCA) inventory for commercial use.

  12. Does an Agent Matter? The Effects of Animated Pedagogical Agents on Multimedia Environments.

    ERIC Educational Resources Information Center

    Craig, Scotty D.; Gholson, Barry

    Data are presented on the effects of Animated Agents on multimedia learning environments with specific concerns of split attention and modality effects. The study was a 3 (agent properties: agent only, agent with gestures, no agent) x 3 (picture features: static picture, sudden onset, animation) factorial design with outcome measures of mental…

  13. The New Agent: A Qualitative Study to Strategically Adapt New Agent Professional Development

    ERIC Educational Resources Information Center

    Baker, Lauri M.; Hadley, Gregg

    2014-01-01

    The qualitative study reported here assessed the needs of agents related to new agent professional development to improve the current model. Agents who participated in new agent professional development within the last 5 years were selected to participate in focus groups to determine concerns and continued needs. Agents enjoyed networking and…

  14. Neuroprotective "agents" in surgery. Secret "agent" man, or common "agent" machine?

    NASA Technical Reports Server (NTRS)

    Andrews, R. J.

    1999-01-01

    The search for clinically-effective neuroprotective agents has received enormous support in recent years--an estimated $200 million by pharmaceutical companies on clinical trials for traumatic brain injury alone. At the same time, the pathophysiology of brain injury has proved increasingly complex, rendering the likelihood of a single agent "magic bullet" even more remote. On the other hand, great progress continues with technology that makes surgery less invasive and less risky. One example is the application of endovascular techniques to treat coronary artery stenosis, where both the invasiveness of sternotomy and the significant neurological complication rate (due to microemboli showering the cerebral vasculature) can be eliminated. In this paper we review aspects of intraoperative neuroprotection both present and future. Explanations for the slow progress on pharmacologic neuroprotection during surgery are presented. Examples of technical advances that have had great impact on neuroprotection during surgery are given both from coronary artery stenosis surgery and from surgery for Parkinson's disease. To date, the progress in neuroprotection resulting from such technical advances is an order of magnitude greater than that resulting from pharmacologic agents used during surgery. The progress over the last 20 years in guidance during surgery (CT and MRI image-guidance) and in surgical access (endoscopic and endovascular techniques) will soon be complemented by advances in our ability to evaluate biological tissue intraoperatively in real-time. As an example of such technology, the NASA Smart Probe project is considered. In the long run (i.e., in 10 years or more), pharmacologic "agents" aimed at the complex pathophysiology of nervous system injury in man will be the key to true intraoperative neuroprotection. In the near term, however, it is more likely that mundane "agents" based on computers, microsensors, and microeffectors will be the major impetus to improved

  15. CATS-based Agents That Err

    NASA Technical Reports Server (NTRS)

    Callantine, Todd J.

    2002-01-01

    This report describes preliminary research on intelligent agents that make errors. Such agents are crucial to the development of novel agent-based techniques for assessing system safety. The agents extend an agent architecture derived from the Crew Activity Tracking System that has been used as the basis for air traffic controller agents. The report first reviews several error taxonomies. Next, it presents an overview of the air traffic controller agents, then details several mechanisms for causing the agents to err in realistic ways. The report presents a performance assessment of the error-generating agents, and identifies directions for further research. The research was supported by the System-Wide Accident Prevention element of the FAA/NASA Aviation Safety Program.

  16. Chaotic neurodynamics for autonomous agents.

    PubMed

    Harter, Derek; Kozma, Robert

    2005-05-01

    Mesoscopic level neurodynamics study the collective dynamical behavior of neural populations. Such models are becoming increasingly important in understanding large-scale brain processes. Brains exhibit aperiodic oscillations with a much more rich dynamical behavior than fixed-point and limit-cycle approximation allow. Here we present a discretized model inspired by Freeman's K-set mesoscopic level population model. We show that this version is capable of replicating the important principles of aperiodic/chaotic neurodynamics while being fast enough for use in real-time autonomous agent applications. This simplification of the K model provides many advantages not only in terms of efficiency but in simplicity and its ability to be analyzed in terms of its dynamical properties. We study the discrete version using a multilayer, highly recurrent model of the neural architecture of perceptual brain areas. We use this architecture to develop example action selection mechanisms in an autonomous agent. PMID:15940987

  17. Novel Antiangiogenic Agents in Dermatology

    PubMed Central

    Berrios, Ricardo L.; Arbiser, Jack L.

    2011-01-01

    Because angiogenesis underlies the pathogenesis of numerous conditions (cancer, psoriasis, macular degeneration), there is a pressing need for continued investigations into angiogenic signaling and potential drug targets. Antiangiogenic agents can be classified as either direct or indirect. Direct antiangiogenics act on untransformed endothelial cells to prevent differentiation and proliferation; indirect antiangiogenics act to inhibit factors involved in proangiogenic signaling. Agents currently available with dermatologic indications are few, while several established and novel biologics targeting various proangiogenic factors are currently being investigated for potential dermatologic uses, but the jury is still out on their efficacy and safety. In this review, we highlight our experience with a group of existing and novel, small molecules that combine several modes of action against angiogenesis in addition to other properties – triarylmethane dyes and fulvene derivatives. PMID:21172300

  18. Bacteriocins as Potential Anticancer Agents

    PubMed Central

    Kaur, Sumanpreet; Kaur, Sukhraj

    2015-01-01

    Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have non-specific toxicity toward normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeutic potential of bacteriocins against various types of cancer cell lines. Bacteriocins are ribosomally-synthesized cationic peptides secreted by almost all groups of bacteria. Some bacteriocins have shown selective cytotoxicity toward cancer cells as compared to normal cells. This makes them promising candidates for further investigation and clinical trials. In this review article, we present the overview of the various cancer cell-specific cytotoxic bacteriocins, their mode of action and efficacies. PMID:26617524

  19. Bacteriocins as Potential Anticancer Agents.

    PubMed

    Kaur, Sumanpreet; Kaur, Sukhraj

    2015-01-01

    Cancer remains one of the leading causes of deaths worldwide, despite advances in its treatment and detection. The conventional chemotherapeutic agents used for the treatment of cancer have non-specific toxicity toward normal body cells that cause various side effects. Secondly, cancer cells are known to develop chemotherapy resistance in due course of treatment. Thus, the demand for novel anti-cancer agents is increasing day by day. Some of the experimental studies have reported the therapeutic potential of bacteriocins against various types of cancer cell lines. Bacteriocins are ribosomally-synthesized cationic peptides secreted by almost all groups of bacteria. Some bacteriocins have shown selective cytotoxicity toward cancer cells as compared to normal cells. This makes them promising candidates for further investigation and clinical trials. In this review article, we present the overview of the various cancer cell-specific cytotoxic bacteriocins, their mode of action and efficacies.

  20. [Pharmacology of bone anabolic agents].

    PubMed

    Matsumoto, Toshio

    2015-10-01

    Bone is constantly remodeled to maintain its volume, structural integrity and strength Currently available bone anabolic agent is teriparatide. Teriparatide increases bone mass and strength via both remodeling-dependent and -independent mechanisms, although remodeling-dependent mechanism overweighs the other. Canonical Wnt signal plays an important role in enhancing osteoblast differentiation and bone formation, and its osteocyte-derived inhibitor, sclerostin, regulates bone formation via the regulation of Wnt signaling. Anti-sclerostin antibody stimulates Wnt signaling and enhances bone formation. Phase II clinical trials with anti-sclerostin antibodies, romosozumab and blosozumab, demonstrated a marked increase in bone mineral density after one year of treatment. The new modality of anabolic agents via remodeling-independent stimulation of bone formation may open up a new avenue for the treatment of osteoporosis.

  1. Oral agents in multiple sclerosis.

    PubMed

    Lorefice, L; Fenu, G; Frau, J; Coghe, G C; Marrosu, M G; Cocco, E

    2015-01-01

    Multiple sclerosis (MS) is a complex autoimmune disease of the central nervous system. Disease-modifying drugs licensed for MS treatment have been developed to reduce relapse rates and halt disease progression. The majority of current MS drugs involve regular, parenteral administration, affecting long-term adherence and thus reducing treatment efficacy. Over the last two decades great progress has been made towards developing new MS therapies with different modes of action and biologic effects. In particular, oral drugs have generated much interest because of their convenience and positive impact on medication adherence. Fingolimod was the first launched oral treatment for relapsing-remitting MS; recently, Teriflunomide and Dimethyl fumarate have also been approved as oral disease-modifying agents. In this review, we summarize and discuss the history, pharmacodynamics, efficacy, and safety of oral agents that have been approved or are under development for the selective treatment of MS. PMID:25924620

  2. Hyperlipidemia sink for anesthetic agents.

    PubMed

    Johnson, Thomas J; Porhomayon, Jahan; Nader, Nader D; Eldesouki, Enas; Smith, Kelly; Hobika, Geoffrey G

    2016-11-01

    We present a case that involves anesthetic resistance during anesthesia for electroconvulsive therapy. Despite adequate dosing of both intravenous and inhalation anesthetics, our patient was resistant to induction of the state of general anesthesia. Subsequently, we noticed extreme hyperlipidemia. We hypothesized that the patient's extreme hyperlipidemia served as an anesthetic "sink" and prevented the full dose of intravenous agents from quickly reaching their intended site of action.

  3. A Potential Nanofiber Membrane Device for Filling Surgical Residual Cavity to Prevent Glioma Recurrence and Improve Local Neural Tissue Reconstruction.

    PubMed

    Huang, Daoxiang; Lin, Chao; Wen, Xuejun; Gu, Shuying; Zhao, Peng

    2016-01-01

    This study aims to develop a novel device with nanofiber membrane capable of sustained release of temozolomide (TMZ) and neuron growth factor (NGF). An improved bio-availability of TMZ and NGF in surroundings proximal to the device was expected to be attained for a prolonged period of time. The device was developed by integrating TMZ-doped polycaprolactone (PCL) nanofiber (TP) membrane and NGF-coated PCL (NGFP) membrane using sodium alginate hydrogel. TP was prepared by direct electrospinning of TMZ/PCL. NGFP membrane was developed by layer-by-layer assembling technology. The incorporation of TMZ-doped nanofiber and NGFP nanofiber in the device was confirmed by scanning electron microscopy. The number of NGF layer in NGF-coated PCL membrane could be readily measured with energy spectrum analysis. The in vitro release study showed that TP-NGFP-TP membrane could efficiently liberate TMZ to inhibit the growth of C6 glioma cells, and sufficient NGF to induce the differentiation of PC12 neuron cells over four weeks. Such TP-NGFP-TP membrane device can be employed as a tampon to fill up surgical residual cavity and afford residual glioma removal, structural support, hemostasis, and local neural tissue reconstruction in the surgical treatment of glioma. The study opens a horizon to develop multifunctional biomaterial device for maximized glioma treatment efficacy. PMID:27548322

  4. A Potential Nanofiber Membrane Device for Filling Surgical Residual Cavity to Prevent Glioma Recurrence and Improve Local Neural Tissue Reconstruction

    PubMed Central

    Huang, Daoxiang; Lin, Chao; Wen, Xuejun; Gu, Shuying; Zhao, Peng

    2016-01-01

    This study aims to develop a novel device with nanofiber membrane capable of sustained release of temozolomide (TMZ) and neuron growth factor (NGF). An improved bio-availability of TMZ and NGF in surroundings proximal to the device was expected to be attained for a prolonged period of time. The device was developed by integrating TMZ-doped polycaprolactone (PCL) nanofiber (TP) membrane and NGF-coated PCL (NGFP) membrane using sodium alginate hydrogel. TP was prepared by direct electrospinning of TMZ/PCL. NGFP membrane was developed by layer-by-layer assembling technology. The incorporation of TMZ-doped nanofiber and NGFP nanofiber in the device was confirmed by scanning electron microscopy. The number of NGF layer in NGF-coated PCL membrane could be readily measured with energy spectrum analysis. The in vitro release study showed that TP-NGFP-TP membrane could efficiently liberate TMZ to inhibit the growth of C6 glioma cells, and sufficient NGF to induce the differentiation of PC12 neuron cells over four weeks. Such TP-NGFP-TP membrane device can be employed as a tampon to fill up surgical residual cavity and afford residual glioma removal, structural support, hemostasis, and local neural tissue reconstruction in the surgical treatment of glioma. The study opens a horizon to develop multifunctional biomaterial device for maximized glioma treatment efficacy. PMID:27548322

  5. Intracranial microcapsule chemotherapy delivery for the localized treatment of rodent metastatic breast adenocarcinoma in the brain

    PubMed Central

    Upadhyay, Urvashi M.; Tyler, Betty; Patta, Yoda; Wicks, Robert; Spencer, Kevin; Scott, Alexander; Masi, Byron; Hwang, Lee; Grossman, Rachel; Cima, Michael; Brem, Henry; Langer, Robert

    2014-01-01

    Metastases represent the most common brain tumors in adults. Surgical resection alone results in 45% recurrence and is usually accompanied by radiation and chemotherapy. Adequate chemotherapy delivery to the CNS is hindered by the blood–brain barrier. Efforts at delivering chemotherapy locally to gliomas have shown modest increases in survival, likely limited by the infiltrative nature of the tumor. Temozolomide (TMZ) is first-line treatment for gliomas and recurrent brain metastases. Doxorubicin (DOX) is used in treating many types of breast cancer, although its use is limited by severe cardiac toxicity. Intracranially implanted DOX and TMZ microcapsules are compared with systemic administration of the same treatments in a rodent model of breast adenocarcinoma brain metastases. Outcomes were animal survival, quantified drug exposure, and distribution of cleaved caspase 3. Intracranial delivery of TMZ and systemic DOX administration prolong survival more than intracranial DOX or systemic TMZ. Intracranial TMZ generates the more robust induction of apoptotic pathways. We postulate that these differences may be explained by distribution profiles of each drug when administered intracranially: TMZ displays a broader distribution profile than DOX. These microcapsule devices provide a safe, reliable vehicle for intracranial chemotherapy delivery and have the capacity to be efficacious and superior to systemic delivery of chemotherapy. Future work should include strategies to improve the distribution profile. These findings also have broader implications in localized drug delivery to all tissue, because the efficacy of a drug will always be limited by its ability to diffuse into surrounding tissue past its delivery source. PMID:25349381

  6. Intracranial microcapsule chemotherapy delivery for the localized treatment of rodent metastatic breast adenocarcinoma in the brain.

    PubMed

    Upadhyay, Urvashi M; Tyler, Betty; Patta, Yoda; Wicks, Robert; Spencer, Kevin; Scott, Alexander; Masi, Byron; Hwang, Lee; Grossman, Rachel; Cima, Michael; Brem, Henry; Langer, Robert

    2014-11-11

    Metastases represent the most common brain tumors in adults. Surgical resection alone results in 45% recurrence and is usually accompanied by radiation and chemotherapy. Adequate chemotherapy delivery to the CNS is hindered by the blood-brain barrier. Efforts at delivering chemotherapy locally to gliomas have shown modest increases in survival, likely limited by the infiltrative nature of the tumor. Temozolomide (TMZ) is first-line treatment for gliomas and recurrent brain metastases. Doxorubicin (DOX) is used in treating many types of breast cancer, although its use is limited by severe cardiac toxicity. Intracranially implanted DOX and TMZ microcapsules are compared with systemic administration of the same treatments in a rodent model of breast adenocarcinoma brain metastases. Out