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Sample records for paclitaxel taxol taxolreg

  1. High-performance liquid chromatographic procedure for the quantitative determination of paclitaxel (Taxol) in human plasma.

    PubMed

    Willey, T A; Bekos, E J; Gaver, R C; Duncan, G F; Tay, L K; Beijnen, J H; Farmen, R H

    1993-11-24

    An isocratic high-performance liquid chromatographic method has been developed and validated for the quantitative determination of paclitaxel (Taxol), a novel antimitotic, anticancer agent, in human plasma. The analysis required 0.5 ml of plasma, and was accomplished by detection of the UV absorbance of paclitaxel at 227 nm following extraction and concentration. The method involved extraction of paclitaxel from plasma, buffered with 0.5 ml of 0.2 M ammonium acetate (pH 5.0), onto 1-ml cyano Bond Elut columns. The eluent was evaporated under nitrogen and low heat, and reconstituted with the mobile phase, acetonitrile-methanol-water (4:1:5, v/v/v) containing 0.01 M ammonium acetate (pH 5.0). The samples were chromatographed on a reversed-phase octyl 5 microns column. The retention time of paclitaxel was 10 min. The validated quantitation range of the method was 10-1000 ng/ml (0.012-1.17 microM) of paclitaxel in plasma. Standard curve correlation coefficients of 0.995 or greater were obtained during validation experiments and analysis of clinical study samples. The observed recovery for paclitaxel was 83%. Epitaxol, a biologically active stereoisomer, and baccatin III, a degradation product, were also chromatographically separated from taxol by this assay. The method was applied to samples from a clinical study of paclitaxel in cancer patients, providing a pharmacokinetic profiling of paclitaxel. PMID:7905005

  2. Bridging Converts a Noncytotoxic nor-Paclitaxel Derivative to a Cytotoxic Analog by Constraining it to the T-Taxol Conformation

    PubMed Central

    Tang, Shoubin; Yang, Chao; Brodie, Peggy; Bane, Susan; Ravindra, Rudravajhala; Sharma, Shubhada; Jiang, Yi; Snyder, James P.; Kingston, David G. I.

    2008-01-01

    The synthesis of the bridged A-nor-paclitaxel 4 has been achieved from paclitaxel in a key test of the T-Taxol conformational hypothesis. Although the unbridged A-nor-paclitaxel 3 is essentially non-cytotoxic, the bridged analog 4 is strongly cytotoxic. This result provides strong evidence for the T-Taxol conformation as the bioactive tubulin-binding conformation of paclitaxel. PMID:16928054

  3. Medium chain triglyceride (MCT) rich, paclitaxel loaded self nanoemulsifying preconcentrate (PSNP): a safe and efficacious alternative to Taxol.

    PubMed

    Patel, Ketan; Patil, Anand; Mehta, Miten; Gota, Vikram; Vavia, Pradeep

    2013-12-01

    The current work was aimed to develop Medium Chain Triglyceride (MCT) rich self nanoemulsifying preconcentrate of paclitaxel (PTX) for parenteral delivery. Very high concentrations of Cremophor EL and ethanol in Taxol have rendered patients to severe side effects. Years of extensive research on development of cost effective and safer vehicle for PTX, have failed to provide a promising replacement for Taxol. MCT was selected as oil owing to its parenteral acceptability, high solubilization capacity and multiple therapeutic benefits in cancer cachexia. PTX precipitation kinetics and reported toxicity profile of Kolliphor HS15 has favored its selection for PTX Self Nanoemulsifying Preconcentrate (PSNP). Presence of 30% free PEG in Kolliphor HS15 (PEG-15-hydroxystearate) restricts its miscibility with MCT, imposing significant challenge in development of MCT rich self nanoemulsifying preconcentrate. Removal of PEG layer from oil-surfactant mixture facilitated the formulation of PSNP with 51% w/w MCT. PSNP exhibited better precipitation kinetic profile, higher PTX loading with negligible hemolysis and histamine release compared to Taxol. PSNP was bioequivalent to Taxol, though V(d) and MRT was significantly higher than Taxol. PSNP showed distinctly better profile in inhibiting tumor growth and maintaining body weight with significantly higher % survival. Thus, PSNP can be a safer vehicle with potential clinical benefits. PMID:24266255

  4. Intraperitoneal delivery of a novel liposome-encapsulated paclitaxel redirects metabolic reprogramming and effectively inhibits cancer stem cells in Taxol(®)-resistant ovarian cancer.

    PubMed

    Shen, Yao-An; Li, Wai-Hou; Chen, Po-Hung; He, Chun-Lin; Chang, Yen-Hou; Chuang, Chi-Mu

    2015-01-01

    Taxol(®) remained as the mainstay therapeutic agent in the treatment of ovarian cancer, however recurrence rate is still high. Cancer stem cells (CSCs) represent a subset of cells in the bulk of tumors and play a central role in inducing drug resistance and recurrence. Furthermore, cancer metabolism has been an area under intensive investigation, since accumulating evidence has shown that CSCs and cancer metabolism are closely linked, an effect named as metabolic reprogramming. In this work, we aimed to investigate the impacts of a novel liposome-encapsulated paclitaxel (Nano-Taxol) on the stemness phenotype and metabolic reprogramming. A paclitaxel-resistant cell line (TR) was established at first. Tumor growth was induced in the mice peritoneal cavity by inoculation of TR cells. A 2x2 factorial experiment was designed to test the therapeutic efficacy in which factor 1 represented the comparison of drugs (Taxol(®) versus Nano-Taxol), while factor 2 represented the delivery route (intravenous versus intraperitoneal delivery). In this work, we found that intraperitoneal delivery of Nano-Taxol redirects metabolic reprogramming, from glycolysis to oxidative phosphorylation, and effectively suppresses cancer stem cells. Also, intraperitoneal delivery of Nano-Taxol led to a significantly better control of tumor growth compared with intravenous delivery of Taxol(®) (current standard treatment). This translational research may serve as a novel pathway for the drug development of nanomedicine. In the future, this treatment modality may be extended to treat several relevant cancers that have been proved to be suitable for the loco-regional delivery of therapeutic agents, including colon cancer, gastric cancer, and pancreatic cancer. PMID:26175846

  5. Intraperitoneal delivery of a novel liposome-encapsulated paclitaxel redirects metabolic reprogramming and effectively inhibits cancer stem cells in Taxol®-resistant ovarian cancer

    PubMed Central

    Shen, Yao-An; Li, Wai-Hou; Chen, Po-Hung; He, Chun-Lin; Chang, Yen-Hou; Chuang, Chi-Mu

    2015-01-01

    Taxol® remained as the mainstay therapeutic agent in the treatment of ovarian cancer, however recurrence rate is still high. Cancer stem cells (CSCs) represent a subset of cells in the bulk of tumors and play a central role in inducing drug resistance and recurrence. Furthermore, cancer metabolism has been an area under intensive investigation, since accumulating evidence has shown that CSCs and cancer metabolism are closely linked, an effect named as metabolic reprogramming. In this work, we aimed to investigate the impacts of a novel liposome-encapsulated paclitaxel (Nano-Taxol) on the stemness phenotype and metabolic reprogramming. A paclitaxel-resistant cell line (TR) was established at first. Tumor growth was induced in the mice peritoneal cavity by inoculation of TR cells. A 2x2 factorial experiment was designed to test the therapeutic efficacy in which factor 1 represented the comparison of drugs (Taxol® versus Nano-Taxol), while factor 2 represented the delivery route (intravenous versus intraperitoneal delivery). In this work, we found that intraperitoneal delivery of Nano-Taxol redirects metabolic reprogramming, from glycolysis to oxidative phosphorylation, and effectively suppresses cancer stem cells. Also, intraperitoneal delivery of Nano-Taxol led to a significantly better control of tumor growth compared with intravenous delivery of Taxol® (current standard treatment). This translational research may serve as a novel pathway for the drug development of nanomedicine. In the future, this treatment modality may be extended to treat several relevant cancers that have been proved to be suitable for the loco-regional delivery of therapeutic agents, including colon cancer, gastric cancer, and pancreatic cancer. PMID:26175846

  6. Exploration of paclitaxel (Taxol) as a treatment for malignant tumors in cats: a descriptive case series.

    PubMed

    Kim, Jennifer; Doerr, Mary; Kitchell, Barbara E

    2015-02-01

    Paclitaxel, an effective chemotherapeutic agent in human oncology, has received little evaluation in feline patients. The diluent used to solubilize paclitaxel, polyoxyethylated castor oil (Cremophor EL), causes anaphylactoid reactions in human and dogs, which limits enthusiasm for use of this agent in veterinary oncology. Nine feline patients with measurable malignant tumors were treated with paclitaxel at a dosage of 80 mg/m(2) intravenously every 21 days for up to two doses. Adverse effects, including evidence of toxicity and anaphylactoid reactions, were assessed. Tumor response, progression and patient time to progression (TTP) were also recorded. Adverse effects included grade III and IV thrombocytopenia, grade III gastrointestinal signs (vomiting and constipation) and hypersensitivity reactions, seen in a total of five patients. Anaphylactoid reactions resolved with appropriate management. Stable disease and partial response were observed in 56% of feline patients. Median TTP was 28 days (range 15-45 days). Intravenous paclitaxel is a safe treatment option for feline malignant tumor patients. Future investigation is warranted to explore the effectiveness and appropriate application of this agent for specific tumor types. PMID:24820996

  7. Polysaccharide-based Noncovalent Assembly for Targeted Delivery of Taxol

    PubMed Central

    Yang, Yang; Zhang, Ying-Ming; Chen, Yong; Chen, Jia-Tong; Liu, Yu

    2016-01-01

    The construction of synthetic straightforward, biocompatible and biodegradable targeted drug delivery system with fluorescent tracking abilities, high anticancer activities and low side effects is still a challenge in the field of biochemistry and material chemistry. In this work, we constructed targeted paclitaxel (Taxol) delivery nanoparticles composed of permethyl-β-cyclodextrin modified hyaluronic acid (HApCD) and porphyrin modified paclitaxel prodrug (PorTaxol), through host-guest and amphiphilic interactions. The obtained nanoparticles (HATXP) were biocompatible and enzymatic biodegradable due to their hydrophilic hyaluronic acid (HA) shell and hydrophobic Taxol core, and exhibited specific targeting internalization into cancer cells via HA receptor mediated endocytosis effects. The cytotoxicity experiments showed that the HATXP exhibited similar anticancer activities to, but much lower side effects than commercial anticancer drug Taxol. The present work would provide a platform for targeted paclitaxel drug delivery and a general protocol for the design of advanced multifunctional nanoscale biomaterials for targeted drug/gene delivery. PMID:26759029

  8. Polysaccharide-based Noncovalent Assembly for Targeted Delivery of Taxol.

    PubMed

    Yang, Yang; Zhang, Ying-Ming; Chen, Yong; Chen, Jia-Tong; Liu, Yu

    2016-01-01

    The construction of synthetic straightforward, biocompatible and biodegradable targeted drug delivery system with fluorescent tracking abilities, high anticancer activities and low side effects is still a challenge in the field of biochemistry and material chemistry. In this work, we constructed targeted paclitaxel (Taxol) delivery nanoparticles composed of permethyl-β-cyclodextrin modified hyaluronic acid (HApCD) and porphyrin modified paclitaxel prodrug (PorTaxol), through host-guest and amphiphilic interactions. The obtained nanoparticles (HATXP) were biocompatible and enzymatic biodegradable due to their hydrophilic hyaluronic acid (HA) shell and hydrophobic Taxol core, and exhibited specific targeting internalization into cancer cells via HA receptor mediated endocytosis effects. The cytotoxicity experiments showed that the HATXP exhibited similar anticancer activities to, but much lower side effects than commercial anticancer drug Taxol. The present work would provide a platform for targeted paclitaxel drug delivery and a general protocol for the design of advanced multifunctional nanoscale biomaterials for targeted drug/gene delivery. PMID:26759029

  9. The cytotoxic activity of Taxol in primary cultures of tumour cells from patients is partly mediated by Cremophor EL.

    PubMed Central

    Nygren, P.; Csoka, K.; Jonsson, B.; Fridborg, H.; Bergh, J.; Hagberg, H.; Glimelius, B.; Brodin, O.; Tholander, B.; Kreuger, A.

    1995-01-01

    In patient tumour samples the activity in vitro of Taxol corresponded fairly well to the known clinical activity and Taxol showed low cross-resistance to standard cytotoxic drugs. However, the Taxol solvent Cremophor EL--ethanol was considerably active alone, whereas paclitaxel formulated in ethanol was less active. Taxol thus seems to contain two components active against patient tumour cells in vitro. PMID:7880727

  10. The Shape of Things to Come: Structural and Synthetic Studies of Taxol and Related Compounds

    PubMed Central

    Kingston, David G. I.

    2007-01-01

    The history of the development of TaxolTM (paclitaxel) as an anticancer drug is reviewed, and some aspects of the phytochemistry of Taxus species and of the medicinal chemistry of taxol are discussed. The nature of the taxol-tubulin interaction is then described, with an emphasis on studies that led to the discovery and experimental proof of the T-taxol conformation as the tubulin-binding conformation of taxol. The implications of this conformation for future drug development are also briefly covered. PMID:17184797

  11. Stabilized micelles as delivery vehicles for paclitaxel.

    PubMed

    Yoncheva, Krassimira; Calleja, Patricia; Agüeros, Maite; Petrov, Petar; Miladinova, Ivanka; Tsvetanov, Christo; Irache, Juan M

    2012-10-15

    Paclitaxel is an antineoplastic drug used against a variety of tumors, but its low aqueous solubility and active removal caused by P-glycoprotein in the intestinal cells hinder its oral administration. In our study, new type of stabilized Pluronic micelles were developed and evaluated as carriers for paclitaxel delivery via oral or intravenous route. The pre-stabilized micelles were loaded with paclitaxel by simple solvent/evaporation technique achieving high encapsulation efficiency of approximately 70%. Gastrointestinal transit of the developed micelles was evaluated by oral administration of rhodamine-labeled micelles in rats. Our results showed prolonged gastrointestinal residence of the marker encapsulated into micelles, compared to a solution containing free marker. Further, the oral administration of micelles in mice showed high area under curve of micellar paclitaxel (similar to the area of i.v. Taxol(®)), longer mean residence time (9-times longer than i.v. Taxol(®)) and high distribution volume (2-fold higher than i.v. Taxol(®)) indicating an efficient oral absorption of paclitaxel delivered by micelles. Intravenous administration of micelles also showed a significant improvement of pharmacokinetic parameters of micellar paclitaxel vs. Taxol(®), in particular higher area under curve (1.2-fold), 5-times longer mean residence time and lower clearance, indicating longer systemic circulation of the micelles. PMID:22721848

  12. Fluorescence imaging analysis of taxol-induced ASTC-a-1 cell death with cell swelling and cytoplasmic vacuolization

    NASA Astrophysics Data System (ADS)

    Chen, Tong-sheng; Sun, Lei; Wang, Longxiang; Wang, Huiying

    2008-02-01

    Taxol (Paclitaxel), an isolated component from the bark of the Pacific yew Taxus brevifolia, exhibits a broad spectrum of clinical activity against human cancers. Taxol can promote microtubule (MT) assembly, inhibit depolymerization, and change MT dynamics, resulting in disruption of the normal reorganization of the microtubule network required for mitosis and cell proliferation. However, the molecular mechanism of taxol-induced cell death is still unclear. In this report, CCK-8 was used to assay the inhibition of taxol on the human lung adenocarcinoma (ASTC-a-1) cells viability, confocal fluorescence microscope was used to monitor the morphology changes of cells with taxol treatment. We for the first time describe the characteristics of taxol-induced cells swelling, cytoplasmic vacuolization and cell death. Taxol induced swelling, cytoplasmatic vacuolization and cell death without cell shrinkage and membrane rupture. These features differ from those of apoptosis and resemble the paraptosis, a novel nonapoptotic PCD.

  13. Design and synthesis of de novo cytotoxic alkaloids by mimicking the bioactive conformation of paclitaxel

    PubMed Central

    Sun, Liang; Veith, Jean M.; Pera, Paula; Bernacki, Ralph J.; Ojima, Iwao

    2010-01-01

    Novel paclitaxel-mimicking alkaloids were designed and synthesized based on a bioactive conformation of paclitaxel, i.e., REDOR-Taxol. The alkaloid 2 bearing a 5-7-6 tricyclic scaffold mimics REDOR-Taxol best among the compounds designed and was found to be the most potent compound against several drug-sensitive and drug-resistant human cancer cell lines. MD simulation study on the paclitaxel mimics 1 and 2 as well as REDOR-Taxol bound to the 1JFF tubulin structure was quite informative to evaluate the level of mimicking. The MD simulation study clearly distinguishes the 5-6-6 and 5-7-6 tricyclic scaffolds, and also shows substantial difference in the conformational stability of the tubulin-bound structures between 2 and REDOR-Taxol. The latter may account for the large difference in potency, and provides critical information for possible improvement in the future design of paclitaxel mimics. PMID:20800500

  14. Hypersensitivity reactions from taxol.

    PubMed

    Weiss, R B; Donehower, R C; Wiernik, P H; Ohnuma, T; Gralla, R J; Trump, D L; Baker, J R; Van Echo, D A; Von Hoff, D D; Leyland-Jones, B

    1990-07-01

    Taxol is an antitumor agent in clinical trial that has been shown to have activity against advanced ovarian carcinoma and melanoma. Hypersensitivity reactions (HSRs) have been one of the toxicities observed with administration of this drug. Of 301 patients treated, 32 patients have had definite (27 patients) or possible (five patients) hypersensitivity reactions to taxol. All but one patient had the reaction from the first or second exposure to this agent. Reactions occurred at a variety of doses and were characterized most frequently by dyspnea, hypotension, bronchospasm, urticaria, and erythematous rashes. Thirteen (41%) patients had received premedication designed to prevent such toxicity; nevertheless, they sustained HSRs. Prolonging the drug infusion appears to have somewhat reduced, but not obviated, the risk of HSRs. The cause (taxol itself or its excipient Cremophor EL; Badische Anilin und Soda-Fabrik AG [BASF], Ludwigshafen, Federal Republic of Germany) and the mechanism of these reactions to taxol are unknown. We provide guidelines to prevent or minimize such toxicity and treat reactions if they still occur. PMID:1972736

  15. Paclitaxel Injection

    MedlinePlus

    ... other medications. Paclitaxel injection manufactured with polyoxyethylated castor oil is used to treat ovarian cancer (cancer that ... and lung cancer. Paclitaxel injection with polyoxyethylated castor oil is also used to treat Kaposi's sarcoma (a ...

  16. An investigation of nitrile transforming enzymes in the chemo-enzymatic synthesis of the taxol sidechain.

    PubMed

    Wilding, Birgit; Veselá, Alicja B; Perry, Justin J B; Black, Gary W; Zhang, Meng; Martínková, Ludmila; Klempier, Norbert

    2015-07-28

    Paclitaxel (taxol) is an antimicrotubule agent widely used in the treatment of cancer. Taxol is prepared in a semisynthetic route by coupling the N-benzoyl-(2R,3S)-3-phenylisoserine sidechain to the baccatin III core structure. Precursors of the taxol sidechain have previously been prepared in chemoenzymatic approaches using acylases, lipases, and reductases, mostly featuring the enantioselective, enzymatic step early in the reaction pathway. Here, nitrile hydrolysing enzymes, namely nitrile hydratases and nitrilases, are investigated for the enzymatic hydrolysis of two different sidechain precursors. Both sidechain precursors, an openchain α-hydroxy-β-amino nitrile and a cyanodihydrooxazole, are suitable for coupling to baccatin III directly after the enzymatic step. An extensive set of nitrilases and nitrile hydratases was screened towards their activity and selectivity in the hydrolysis of two taxol sidechain precursors and their epimers. A number of nitrilases and nitrile hydratases converted both sidechain precursors and their epimers. PMID:26107443

  17. Isolation of anticancer drug TAXOL from Pestalotiopsis breviseta with apoptosis and B-Cell lymphoma protein docking studies

    PubMed Central

    Kathiravan, G.; Sureban, Sripathi M.; Sree, Harsha N.; Bhuvaneshwari, V.; Kramony, Evelin

    2012-01-01

    Background: Extraction and investigation of TAXOL from Pestalotiopsis breviseta (Sacc.) using protein docking, which is a computational technique that samples conformations of small molecules in protein-binding sites. Scoring functions are used to assess which of these conformations best complements the protein binding site and active site prediction. Materials and Methods: Coelomycetous fungi P. breviseta (Sacc.) Steyaert was screened for the production of TAXOL, an anticancer drug. Results: TAXOL production was confirmed by the following methods: Ultraviolet (UV) spectroscopic analysis, Infrared analysis, High performance liquid chromatography analysis (HPLC), and Liquid chromatography mass spectrum (LC-MASS). TAXOL produced by the fungi was compared with authentic TAXOL, and protein docking studies were performed. Conclusion: The BCL2 protein of human origin showed a higher affinity toward the compound paclitaxel. It has the binding energy value of −13.0061 (KJ/Mol) with four hydrogen bonds. PMID:24808664

  18. Randomly methylated ?-cyclodextrin derivatives enhance taxol permeability through human intestinal epithelial Caco-2 cell monolayer.

    PubMed

    Fenyvesi, Ferenc; Kiss, Tmea; Fenyvesi, Eva; Szente, Lajos; Veszelka, Szilvia; Deli, Mria A; Vradi, Judit; Fehr, Plma; Ujhelyi, Zoltn; Tsaki, Arpd; Vecsernys, Mikls; Bcskay, Ildik

    2011-11-01

    Intestinal absorption and bioavailability of taxol are limited by its low solubility and P-glycoprotein (Pgp) activity. Methylated ?-cyclodextrins (CDs) effectively form complexes with paclitaxel but randomly methylated ?-cyclodextrin (RAMEB) is cytotoxic in high concentrations. Second-generation derivatives containing monoamino (MaRAMEB) and succinylated (SuRAMEB) ionic substituents with similar inclusion capacity but less toxicity could be promising alternatives of RAMEB. Our aim was to examine and compare the efficacy of MaRAMEB and SuRAMEB with the parental RAMEB on taxol bidirectional permeability using the Caco-2 model. Taxol permeability was not changed by 30-min pretreatment with CDs. In co-treatment with ?-cyclodextrins, the apical to basolateral taxol flux was 4 to 6 times greater than in untreated monolayers and it was also higher than in cells treated with Pgp inhibitor cyclosporin A. No decrease in basolateral to apical taxol flux was observed in pretreatment or co-treatment with CDs, suggesting no Pgp inhibition. All three CDs showed similar effects on taxol permeability but RAMEB altered tight junction protein distribution and significantly decreased transepithelial electrical resistance. None of the CDs modified paracellular permeability to mannitol and polyethylene glycol 4000. In conclusion, second-generation derivatives of methyl-?-cyclodextrin, especially MaRAMEB, enhanced taxol permeability across Caco-2 cells with less toxicity and similar effectiveness as RAMEB. PMID:21660974

  19. Isoprenoid Pathway Optimization for Taxol Precursor Overproduction in Escherichia coli

    PubMed Central

    Ajikumar, Parayil Kumaran; Xiao, Wen-Hai; Tyo, Keith E. J.; Wang, Yong; Simeon, Fritz; Leonard, Effendi; Mucha, Oliver; Phon, Too Heng; Pfeifer, Blaine; Stephanopoulos, Gregory

    2011-01-01

    Taxol (paclitaxel) is a potent anticancer drug first isolated from the Taxus brevifolia Pacific yew tree. Currently, cost-efficient production of Taxol and its analogs remains limited. Here, we report a multivariate-modular approach to metabolic-pathway engineering that succeeded in increasing titers of taxadiene—the first committed Taxol intermediate—approximately 1 gram per liter (~15,000-fold) in an engineered Escherichia coli strain. Our approach partitioned the taxadiene metabolic pathway into two modules: a native upstream methylerythritol-phosphate (MEP) pathway forming isopentenyl pyrophosphate and a heterologous downstream terpenoid–forming pathway. Systematic multivariate search identified conditions that optimally balance the two pathway modules so as to maximize the taxadiene production with minimal accumulation of indole, which is an inhibitory compound found here. We also engineered the next step in Taxol biosynthesis, a P450-mediated 5α-oxidation of taxadiene to taxadien-5α-ol. More broadly, the modular pathway engineering approach helped to unlock the potential of the MEP pathway for the engineered production of terpenoid natural products. PMID:20929806

  20. Synthesis of Paclitaxel. 1. Synthesis of the ABC Ring of Paclitaxel by SmI2-Mediated Cyclization.

    PubMed

    Fukaya, Keisuke; Tanaka, Yuta; Sato, Ayako C; Kodama, Keisuke; Yamazaki, Hirohisa; Ishimoto, Takeru; Nozaki, Yasuyoshi; Iwaki, Yuki M; Yuki, Yohei; Umei, Kentaro; Sugai, Tomoya; Yamaguchi, Yu; Watanabe, Ami; Oishi, Takeshi; Sato, Takaaki; Chida, Noritaka

    2015-06-01

    A convergent synthesis of the ABC ring of antitumor natural product paclitaxel (Taxol) is described. SmI2-mediated reductive cyclization of an allylic benzoate possessing an aldehyde function, synthesized from tri-O-acetyl-d-glucal and 1,3-cyclohexanedione, smoothly afforded the highly strained 6-8-6 tricarbocyclic structure in 66% yield. PMID:26010812

  1. Development and Evaluation of Transferrin-Stabilized Paclitaxel Nanocrystal Formulation

    PubMed Central

    Lu, Ying; Wang, Zhao-hui; Li, Tonglei; McNally, Helen; Park, Kinam; Sturek, Michael

    2014-01-01

    The aim of the present study was to prepare and evaluate a paclitaxel nanocrystal-based formulation stabilized by serum protein transferrin in a non-covalent manner. The pure paclitaxel nanocrystals were first prepared using an antisolvent precipitation method augmented by sonication. The serum protein transferrin was selected for use after evaluating the stabilizing effect of several serum proteins including albumin and immunoglobulin G. The formulation contained approximately 55~60% drug and was stable for at least 3 months at 4 °C. In vivo antitumor efficacy studies using mice inoculated with KB cells demonstrate significantly higher tumor inhibition rate of 45.1% for paclitaxel-transferrin formulation compared to 28.8% for paclitaxel nanosuspension treatment alone. Interestingly, the Taxol® formulation showed higher antitumor activity than the paclitaxel-transferrin formulation, achieving a 93.3% tumor inhibition rate 12 days post initial dosing. However, the paclitaxel-transferrin formulation showed a lower level of toxicity, which is indicated by steady increase in body weight of mice over the treatment period. In comparison, treatment with Taxol® resulted in toxicity issues as body weight decreased. These results suggest the potential benefit of using a serum protein in a non-covalent manner in conjunction with paclitaxel nanocrystals as a promising drug delivery model for anticancer therapy. PMID:24378441

  2. [Advances of taxol combinatorial biosynthesis].

    PubMed

    Li, Jie; Wang, Chunmei

    2014-03-01

    Taxol is a kind of isoprenoid with strong anticancer activity. It is difficult to be obtained because of its low concentration in nature, which hinders its application in cancer treatment. Recently, biosynthesis methods for taxol production have attracted more attentions. Several systems including Escherichia coli, Saccharomyces cerevisiae, Physcomitrella patens, Arabidopsis, tomato and ginseng were explored. This review focuses on the advance in biosynthesis of taxol in different systems and features the bottleneck of scale fermentation for producing the intermediates. At the same time some advices for the further were given. At last, the future and character of Physcomitrella patens system used in taxol combinatorial biosynthesis were analyzed based on our lab's research. PMID:25007572

  3. Ototoxicity of paclitaxel in rat cochlear organotypic cultures

    SciTech Connect

    Dong, Yang; Ding, Dalian; Jiang, Haiyan; Shi, Jian-rong; Salvi, Richard; Roth, Jerome A.

    2014-11-01

    Paclitaxel (taxol) is a widely used antineoplastic drug employed alone or in combination to treat many forms of cancer. Paclitaxel blocks microtubule depolymerization thereby stabilizing microtubules and suppressing cell proliferation and other cellular processes. Previous reports indicate that paclitaxel can cause mild to moderate sensorineural hearing loss and some histopathologic changes in the mouse cochlea; however, damage to the neurons and the underlying cell death mechanisms are poorly understood. To evaluate the ototoxicity of paclitaxel in more detail, cochlear organotypic cultures from postnatal day 3 rats were treated with paclitaxel for 24 or 48 h with doses ranging from 1 to 30 μM. No obvious histopathologies were observed after 24 h treatment with any of the paclitaxel doses employed, but with 48 h treatment, paclitaxel damaged cochlear hair cells in a dose-dependent manner and also damaged auditory nerve fibers and spiral ganglion neurons (SGN) near the base of the cochlea. TUNEL labeling was negative in the organ of Corti, but positive in SGN with karyorrhexis 48 h after 30 μM paclitaxel treatment. In addition, caspase-6, caspase-8 and caspase-9 labeling was present in SGN treated with 30 μM paclitaxel for 48 h. These results suggest that caspase-dependent apoptotic pathways are involved in paclitaxel-induced damage of SGN, but not hair cells in cochlea. - Highlights: • Paclitaxel was toxic to cochlear hair cells and spiral ganglion neurons. • Paclitaxel-induced spiral ganglion degeneration was apoptotic. • Paclitaxel activated caspase-6, -8 and -8 in spiral ganglion neurons.

  4. Taxol induces concentration-dependent phosphatidylserine (PS) externalization and cell cycle arrest in ASTC-a-1 cells

    NASA Astrophysics Data System (ADS)

    Guo, Wen-jing; Chen, Tong-sheng

    2010-02-01

    Taxol (Paclitaxel) is an important natural product for the treatment of solid tumors. Different concentrations of taxol can trigger distinct effects on both the cellular microtubule network and biochemical pathways. Apoptosis induced by low concentrations (5-30 nM) of taxol was associated with mitotic arrest, alteration of microtubule dynamics and/or G2/M cell cycle arrest, whereas high concentrations of this drug (0.2-30 μM) caused significant microtubule damage, and was found recently to induce cytoplasm vacuolization in human lung adenocarcinoma (ASTC-a-1) cells. In present study, cell counting kit (CCK-8) assay, confocal microscope, and flow cytometry analysis were used to analyze the cell death form induced by 35 nM and 70 μM of taxol respectively in human lung adenocarcinoma (ASTC-a-1) cells. After treatment of 35 nM taxol for 48 h, the OD450 value was 0.80, and 35 nM taxol was found to induce dominantly cell death in apoptotic pathway such as phosphatidylserine (PS) externalization, G2/M phase arrest after treatment for 24 h, and nuclear fragmentation after treatment for 48 h. After 70 μM taxol treated the cell for 24 h, the OD450 value was 1.01, and 70 μM taxol induced cytoplasm vacuolization programmed cell death (PCD) and G2/M phase as well as the polyploidy phase arrest in paraptotic-like cell death. These findings imply that the regulated signaling pathway of cell death induced by taxol is dependent on taxol concentration in ASTC-a-1 cells.

  5. Paclitaxel Nano-Delivery Systems: A Comprehensive Review

    PubMed Central

    Ma, Ping; Mumper, Russell J.

    2013-01-01

    Paclitaxel is one of the most effective chemotherapeutic drugs ever developed and is active against a broad range of cancers, such as lung, ovarian, and breast cancers. Due to its low water solubility, paclitaxel is formulated in a mixture of Cremophor EL and dehydrated ethanol (50:50, v/v) a combination known as Taxol. However, Taxol has some severe side effects related to Cremophor EL and ethanol. Therefore, there is an urgent need for the development of alternative Taxol formulations. The encapsulation of paclitaxel in biodegradable and non-toxic nano-delivery systems can protect the drug from degradation during circulation and in-turn protect the body from toxic side effects of the drug thereby lowering its toxicity, increasing its circulation half-life, exhibiting improved pharmacokinetic profiles, and demonstrating better patient compliance. Also, nanoparticle-based delivery systems can take advantage of the enhanced permeability and retention (EPR) effect for passive tumor targeting, therefore, they are promising carriers to improve the therapeutic index and decrease the side effects of paclitaxel. To date, paclitaxel albumin-bound nanoparticles (Abraxane®) have been approved by the FDA for the treatment of metastatic breast cancer and non-small cell lung cancer (NSCLC). In addition, there are a number of novel paclitaxel nanoparticle formulations in clinical trials. In this comprehensive review, several types of developed paclitaxel nano-delivery systems will be covered and discussed, such as polymeric nanoparticles, lipid-based formulations, polymer conjugates, inorganic nanoparticles, carbon nanotubes, nanocrystals, and cyclodextrin nanoparticles. PMID:24163786

  6. Diversity of endophytic fungi and screening of fungal paclitaxel producer from Anglojap yew, Taxus x media

    PubMed Central

    2013-01-01

    Background Endophytic fungi represent underexplored resource of novel lead compounds and have a capacity to produce diverse class of plant secondary metabolites. Here we investigated endophytic fungi diversity and screening of paclitaxel-producing fungi from Taxus x media. Results Eighty-one endophytic fungi isolated from T. media were grouped into 8 genera based on the morphological and molecular identification. Guignardia and Colletotrichum were the dominant genera, whereas the remaining genera were infrequent groups. The genera Glomerella and Gibberella were first reported in Taxus. Three representative species of the distinct genera gave positive hits by molecular marker screening and were capable of producing taxol which were validated by HPLC-MS. Among these 3 taxol-producing fungi, the highest yield of taxol was 720 ng/l by Guignardia mangiferae HAA11 compared with those of Fusarium proliferatum HBA29 (240 ng/l) and Colletotrichum gloeosporioides TA67 (120 ng/l). This is the first report of taxol producer from Guignardia. Moreover, the lower similarities of ts and bapt between microbial and plant origin suggested that fungal taxol biosynthetic cluster might be repeatedly invented during evolution, nor horizontal gene transfer from Taxus species. Conclusions Taxol-producing endophytic fungi could be a fascinating reservoir to generate taxol-related drug lead and to elucidate the remained 5 unknown genes or the potential regulation mechanism in the taxol biosynthesis pathway. PMID:23537181

  7. Paclitaxel accelerates spontaneous calcium oscillations in cardiomyocytes by interacting with NCS-1 and the InsP3R

    PubMed Central

    Zhang, Kun; Heidrich, Felix M.; DeGray, Brenda; Boehmerle, Wolfgang; Ehrlich, Barbara E.

    2010-01-01

    Paclitaxel (Taxol) is a microtubule-stabilizing compound that is used for cancer chemotherapy. However, Taxol administration is limited by serious side effects including cardiac arrhythmia, which cannot be explained by its microtubule-stabilizing effect. Recently, neuronal calcium sensor 1 (NCS-1), a calcium binding protein that modulates the inositol-1,4,5-trisphosphate receptor (InsP3R), was described as a binding partner of Taxol and as a substrate of calpain. We examined calcium signaling processes in cardiomyocytes after treatment with Taxol to investigate the basis of Taxol-induced cardiac arrhythmia. After treating isolated neonatal rat ventricular myocytes with a therapeutic concentration of Taxol for several hours live cell imaging experiments showed that the frequency of spontaneous calcium oscillations significantly increased. This effect was not mimicked by other tubulin-stabilizing agents. However, it was prevented by inhibiting the InsP3R. Taxol treated cells had increased expression of NCS-1, an effect also detectable after Taxol administration in vivo. Short hairpin RNA mediated knock down of NCS-1 decreased InsP3R dependent intracellular calcium release, whereas Taxol treatment, that increased NCS-1 levels, increased InsP3R dependent calcium release. The effects of Taxol were ryanodine receptor independent. At the single channel level Taxol and NCS-1 mediated an increase in InsP3R activity. Calpain activity was not affected by Taxol in cardiomyocytes suggesting a calpain independent signaling pathway. In short, our study shows that Taxol impacts calcium signaling and calcium oscillations in cardiomyocytes through NCS-1 and the InsP3R. PMID:20801127

  8. Alterations in Ovarian Cancer Cell Adhesion Drive Taxol Resistance by Increasing Microtubule Dynamics in a FAK-dependent Manner

    PubMed Central

    McGrail, Daniel J.; Khambhati, Niti N.; Qi, Mark X.; Patel, Krishan S.; Ravikumar, Nithin; Brandenburg, Chandler P.; Dawson, Michelle R.

    2015-01-01

    Chemorefractory ovarian cancer patients show extremely poor prognosis. Microtubule-stabilizing Taxol (paclitaxel) is a first-line treatment against ovarian cancer. Despite the close interplay between microtubules and cell adhesion, it remains unknown if chemoresistance alters the way cells adhere to their extracellular environment, a process critical for cancer metastasis. To investigate this, we isolated Taxol-resistant populations of OVCAR3 and SKOV3 ovarian cancer cell lines. Though Taxol-resistant cells neither effluxed more drug nor gained resistance to other chemotherapeutics, they did display increased microtubule dynamics. These changes in microtubule dynamics coincided with faster attachment rates and decreased adhesion strength, which correlated with increased surface ?1-integrin expression and decreased focal adhesion formation, respectively. Adhesion strength correlated best with Taxol-sensitivity, and was found to be independent of microtubule polymerization but dependent on focal adhesion kinase (FAK), which was up-regulated in Taxol-resistant cells. FAK inhibition also decreased microtubule dynamics to equal levels in both populations, indicating alterations in adhesive signaling are up-stream of microtubule dynamics. Taken together, this work demonstrates that Taxol-resistance dramatically alters how ovarian cancer cells adhere to their extracellular environment causing down-stream increases in microtubule dynamics, providing a therapeutic target that may improve prognosis by not only recovering drug sensitivity, but also decreasing metastasis. PMID:25886093

  9. Independent evaluation of the anatomical and behavioral effects of Taxol in rat models of spinal cord injury

    PubMed Central

    Popovich, Phillip G.; Tovar, C. Amy; Lemeshow, Stanley; Yin, Qin; Jakeman, Lyn B.

    2014-01-01

    The goal of the current manuscript was to replicate published data that show intrathecal infusions of Taxol ® (paclitaxel), an anti-neoplastic microtubule stabilizing agent, reduce fibrogliotic scarring caused by a dorsal spinal hemisection (DHx) injury and increase functional recovery and growth of serotonergic axons after moderate spinal contusion injury. These experiments were completed as part of an NIH-NINDS contract entitled “Facilities of Research Excellence – Spinal Cord Injury (FORE-SCI) – Replication”. Here, data are presented that confirm the anti-scarring effects of Taxol after DHx injury; however, Taxol did not confer neuroprotection or promote serotonergic axon growth nor did it improve functional recovery in a model of moderate spinal contusion injury. Thus, only partial replication was achieved. Possible explanations for disparate results in our studies and published data are discussed. PMID:24999028

  10. Paclitaxel and concurrent radiation for locally advanced pancreatic carcinoma.

    PubMed

    Safran, H; Cioffi, W; Iannitti, D; Mega, A; Akerman, P

    1998-11-01

    An effective local-regional therapy is needed for adenocarcinomas of the pancreas. Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton NJ) may enhance the effect of radiation therapy. Paclitaxel synchronizes cells at G2/M, a relatively radiosensitive phase of the cell cycle. We have shown that response to paclitaxel and concurrent radiation (paclitaxel/RT) was not affected by p53 mutations in non-small cell lung cancer (NSCLC). This suggested that paclitaxel/RT was a rationale treatment approach for other malignancies which frequently harbor p53 mutations such as upper gastrointestinal malignancies. We have completed a phase I study of paclitaxel/RT for locally advanced pancreatic and gastric cancers. The maximum tolerated dose (MTD) of paclitaxel was 50 mg/m2/week for 6 weeks with abdominal radiation. The dose limiting toxicities were abdominal pain within the radiation field, nausea and anorexia. Twenty-five patients with locally advanced pancreatic cancer have now completed treatment at the phase II dose level of paclitaxel 50 mg/m2/week with 50 Gy concurrent RT. Thus far, the only grade 3/4 toxicities have been hypersensitivity reactions in 2 patients, asymptomatic grade 4 neutropenia in 3 patients, and non-neutropenic biliary sepsis in 1 patient. Of the first 22 assessable patients treated at the phase II study, 8 obtained a partial response (PR) for a preliminary response rate of 36%. These findings demonstrate that paclitaxel/RT is well tolerated with substantial activity for locally advanced pancreatic cancer. PMID:9792903

  11. STAT3-dependent TXNDC17 expression mediates Taxol resistance through inducing autophagy in human colorectal cancer cells.

    PubMed

    Zhang, Zhongde; Wang, Aihua; Li, Hui; Zhi, Hui; Lu, Feng

    2016-06-10

    Taxol (paclitaxel) is one of the taxane class of anticancer drugs as a first-line chemotherapeutic agent against many cancers including colorectal cancer, breast cancer, non-small cell lung cancer, ovarian cancer and so on. It is verified to induce cytotoxicity in a concentration and time-dependent manner. Numerous novel formulations of Taxol have been remanufactured for better therapeutic effect. Though Taxol works as a common anticancer drug for a long time in clinical practice, drug resistance is a major limitation of its long-term administration. In-depth research on drug resistance is still in progress and researchers have made some achievements, however, the mechanism or key molecule related to Taxol resistance in colorectal cancer still remains to be explored. In the present study, we observed that the high expression of TXNDC17 (thioredoxin domain containing 17) was associated with Taxol resistance in colorectal cancer cells. And TXNDC17 mediated Taxol resistance was related with increased basal autophagy level. Taxol exposure induced high levels of phospho-STAT3 (Tyr 705) and TXNDC17; and increase of basal autophagy in colorectal cancer cells. TXNDC17 overexpression cells obtained Taxol resistance and a high level of autophagy, and it is not surprising that stable downregulation of TXNDC17 accordingly reversed these phenomena. Interestingly, STAT3 could similarly work as TXNDC17 in spite of slighter effect compared to TXNDC17. And it has been proved that phospho-STAT3 (Tyr 705) possesses transcriptional regulation activity through forming dimmers. Many research revealed that transcription factor STAT3 affected more than 1000 gene products, and TXNDC17 is predicted to be a target gene of STAT3 at UCSC database. For the first time, we found STAT3 could bind promoter region of TXNDC17 (-623bp to -58bp relative to the transcription start site (TSS)) for regulating its expression. These results suggest the possibility that TXNDC17 could play an important role in Taxol resistance via enhancing autophagy in human colorectal cancer cells. TXNDC17 may become a potential target of colorectal cancer therapeutics. PMID:26976343

  12. In vitro cytotoxicity of paclitaxel/beta-cyclodextrin complexes for HIPEC.

    PubMed

    Bouquet, W; Boterberg, T; Ceelen, W; Pattyn, P; Peeters, M; Bracke, M; Remon, J P; Vervaet, C

    2009-02-01

    Hyperthermic intraperitoneal chemotherapy (HIPEC) is a promising strategy in the treatment of peritoneal carcinomatosis. To perform HIPEC, a tensioactive- and solvent-free paclitaxel formulation consisting of water-soluble paclitaxel/randomly methylated-beta-cyclodextrin (Pac/RAMEB) complexes was developed previously. Using MTT and SRB assays the cytotoxic activity of this formulation versus Taxol, was evaluated as well as the cytotoxicity of the different formulation excipients (RAMEB and Cremophor EL. The possible synergistic effect of heat and paclitaxel-based chemotherapy during HIPEC was also evaluated in vitro. The cytotoxicity assays revealed differences in viability between Cremophor EL and RAMEB treated cells of 40 and 50% for the CaCo-2 human and the CC531s rat colon cancer line, respectively, in favour of RAMEB. Despite the higher cytotoxicity of Cremophor EL, Pac/RAMEB complexes and Taxol were equipotent. Using the MTT and SRB assays the average difference in viability between both cell lines was below 10% and IC50 values showed no significant difference. Hyperthermia after drug administration (41 degrees C during 1h) had no effect on cell viability. These results indicated that it was possible to reformulate paclitaxel with a less cytotoxic vehicle while maintaining the cytotoxic activity of the formulation and that there is no synergism between paclitaxel and heat for in vitro cytotoxicity. PMID:18938234

  13. [Nab-paclitaxel].

    PubMed

    Lopez-Trabada Ataz, Daniel; Dumont, Sarah; André, Thierry

    2015-06-01

    Paclitaxel is conventionally used in a wide range of oncology indications. Nab-paclitaxel is synthesized by a process of high pressure homogenization of paclitaxel in the presence of human albumin and it was originally developed to reduce the toxicity usually associated with cremophor in soluble paclitaxel and to increase its penetration in tumor tissues. After the trials that led to its approval in first-line treatment of metastatic pancreatic carcinomas and in second line therapy for metastatic breast cancer, nab-paclitaxel is being tested for many other situations in oncology due to its profile of security and its good tolerance. Different lines of research are being developed about the possible biomarkers that could predict the effect of nab-paclitaxel. This review summarizes the results of trials that led to the approval of the nab-paclitaxel in advanced breast cancer and pancreatic cancer, and also resumes the lines of research to the future development of the drug. PMID:26008630

  14. Development of New Lipid-Based Paclitaxel Nanoparticles Using Sequential Simplex Optimization

    PubMed Central

    Dong, Xiaowei; Mattingly, Cynthia A.; Tseng, Michael; Cho, Moo; Adams, Val R.; Mumper, Russell J.

    2008-01-01

    The objective of these studies was to develop Cremophor-free lipid-based paclitaxel (PX) nanoparticle formulations prepared from warm microemulsion precursors. To identify and optimize new nanoparticles, experimental design was performed combining Taguchi array and sequential simplex optimization. The combination of Taguchi array and sequential simplex optimization efficiently directed the design of paclitaxel nanoparticles. Two optimized paclitaxel nanoparticles (NPs) were obtained: G78 NPs composed of glyceryl tridodecanoate (GT) and polyoxyethylene 20-stearyl ether (Brij 78), and BTM NPs composed of Miglyol 812, Brij 78 and D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS). Both nanoparticles successfully entrapped paclitaxel at a final concentration of 150 μg/ml (over 6% drug loading) with particle sizes less than 200 nm and over 85% of entrapment efficiency. These novel paclitaxel nanoparticles were stable at 4°C over three months and in PBS at 37°C over 102 hours as measured by physical stability. Release of paclitaxel was slow and sustained without initial burst release. Cytotoxicity studies in MDA-MB-231 cancer cells showed that both nanoparticles have similar anticancer activities compared to Taxol®. Interestingly, PX BTM nanocapsules could be lyophilized without cryoprotectants. The lyophilized powder comprised only of PX BTM NPs in water could be rapidly rehydrated with complete retention of original physicochemical properties, in-vitro release properties, and cytotoxicity profile. Sequential Simplex Optimization has been utilized to identify promising new lipid-based paclitaxel nanoparticles having useful attributes. PMID:19111929

  15. Global Inhibition of Reactive Oxygen Species (ROS) Inhibits Paclitaxel-Induced Painful Peripheral Neuropathy

    PubMed Central

    Fidanboylu, Mehmet; Griffiths, Lisa A.; Flatters, Sarah J. L.

    2011-01-01

    Paclitaxel (Taxol®) is a widely used chemotherapeutic agent that has a major dose limiting side-effect of painful peripheral neuropathy. Currently there is no effective therapy for the prevention or treatment of chemotherapy-induced painful peripheral neuropathies. Evidence for mitochondrial dysfunction during paclitaxel-induced pain was previously indicated with the presence of swollen and vacuolated neuronal mitochondria. As mitochondria are a major source of reactive oxygen species (ROS), the aim of this study was to examine whether pharmacological inhibition of ROS could reverse established paclitaxel-induced pain or prevent the development of paclitaxel-induced pain. Using a rat model of paclitaxel-induced pain (intraperitoneal 2 mg/kg paclitaxel on days 0, 2, 4 & 6), the effects of a non-specific ROS scavenger, N-tert-Butyl-α-phenylnitrone (PBN) and a superoxide selective scavenger, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL) were compared. Systemic 100 mg/kg PBN administration markedly inhibited established paclitaxel-induced mechanical hypersensitivity to von Frey 8 g and 15 g stimulation and cold hypersensitivity to plantar acetone application. Daily systemic administration of 50 mg/kg PBN (days −1 to 13) completely prevented mechanical hypersensitivity to von Frey 4 g and 8 g stimulation and significantly attenuated mechanical hypersensitivity to von Frey 15 g. Systemic 100 mg/kg TEMPOL had no effect on established paclitaxel-induced mechanical or cold hypersensitivity. High dose (250 mg/kg) systemic TEMPOL significantly inhibited mechanical hypersensitivity to von Frey 8 g & 15 g, but to a lesser extent than PBN. Daily systemic administration of 100 mg/kg TEMPOL (day −1 to 12) did not affect the development of paclitaxel-induced mechanical hypersensitivity. These data suggest that ROS play a causal role in the development and maintenance of paclitaxel-induced pain, but such effects cannot be attributed to superoxide radicals alone. PMID:21966458

  16. Global inhibition of reactive oxygen species (ROS) inhibits paclitaxel-induced painful peripheral neuropathy.

    PubMed

    Fidanboylu, Mehmet; Griffiths, Lisa A; Flatters, Sarah J L

    2011-01-01

    Paclitaxel (Taxol®) is a widely used chemotherapeutic agent that has a major dose limiting side-effect of painful peripheral neuropathy. Currently there is no effective therapy for the prevention or treatment of chemotherapy-induced painful peripheral neuropathies. Evidence for mitochondrial dysfunction during paclitaxel-induced pain was previously indicated with the presence of swollen and vacuolated neuronal mitochondria. As mitochondria are a major source of reactive oxygen species (ROS), the aim of this study was to examine whether pharmacological inhibition of ROS could reverse established paclitaxel-induced pain or prevent the development of paclitaxel-induced pain. Using a rat model of paclitaxel-induced pain (intraperitoneal 2 mg/kg paclitaxel on days 0, 2, 4 & 6), the effects of a non-specific ROS scavenger, N-tert-Butyl-α-phenylnitrone (PBN) and a superoxide selective scavenger, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL) were compared. Systemic 100 mg/kg PBN administration markedly inhibited established paclitaxel-induced mechanical hypersensitivity to von Frey 8 g and 15 g stimulation and cold hypersensitivity to plantar acetone application. Daily systemic administration of 50 mg/kg PBN (days -1 to 13) completely prevented mechanical hypersensitivity to von Frey 4 g and 8 g stimulation and significantly attenuated mechanical hypersensitivity to von Frey 15 g. Systemic 100 mg/kg TEMPOL had no effect on established paclitaxel-induced mechanical or cold hypersensitivity. High dose (250 mg/kg) systemic TEMPOL significantly inhibited mechanical hypersensitivity to von Frey 8 g & 15 g, but to a lesser extent than PBN. Daily systemic administration of 100 mg/kg TEMPOL (day -1 to 12) did not affect the development of paclitaxel-induced mechanical hypersensitivity. These data suggest that ROS play a causal role in the development and maintenance of paclitaxel-induced pain, but such effects cannot be attributed to superoxide radicals alone. PMID:21966458

  17. Inhibition of glycogen synthase kinase 3β activity with lithium prevents and attenuates paclitaxel-induced neuropathic pain.

    PubMed

    Gao, M; Yan, X; Weng, H-R

    2013-12-19

    Paclitaxel (taxol) is a first-line chemotherapy-drug used to treat many types of cancers. Neuropathic pain and sensory dysfunction are the major toxicities, which are dose-limiting and significantly reduce the quality of life in patients. Two known critical spinal mechanisms underlying taxol-induced neuropathic pain are an increased production of pro-inflammatory cytokines including interleukin-1β (IL-1β) and suppressed glial glutamate transporter activities. In this study, we uncovered that increased activation of glycogen synthase kinase 3beta (GSK3β) in the spinal dorsal horn was concurrently associated with increased protein expressions of GFAP, IL-1β and a decreased protein expression of glial glutamate transporter 1 (GLT-1), as well as the development and maintenance of taxol-induced neuropathic pain. The enhanced GSK3β activities were supported by the concurrently decreased AKT and mTOR activities. The changes of all these biomarkers were basically prevented when animals received pre-emptive lithium (a GSK3β inhibitor) treatment, which also prevented the development of taxol-induced neuropathic pain. Further, chronic lithium treatment, which began on day 11 after the first taxol injection, reversed the existing mechanical and thermal allodynia induced by taxol. The taxol-induced increased GSK3β activities and decreased AKT and mTOR activities in the spinal dorsal horn were also reversed by lithium. Meanwhile, protein expressions of GLT-1, GFAP and IL-1β in the spinal dorsal horn were improved. Hence, suppression of spinal GSK3β activities is a key mechanism used by lithium to reduce taxol-induced neuropathic pain, and targeting spinal GSK3β is an effective approach to ameliorate GLT-1 expression and suppress the activation of astrocytes and IL-1β over-production in the spinal dorsal horn. PMID:24070631

  18. Differential microRNA expression signatures and cell type-specific association with Taxol resistance in ovarian cancer cells

    PubMed Central

    Kim, Yong-Wan; Kim, Eun Young; Jeon, Doin; Liu, Juinn-Lin; Kim, Helena Suhyun; Choi, Jin Woo; Ahn, Woong Shick

    2014-01-01

    Paclitaxel (Taxol) resistance remains a major obstacle for the successful treatment of ovarian cancer. MicroRNAs (miRNAs) have oncogenic and tumor suppressor activity and are associated with poor prognosis phenotypes. miRNA screenings for this drug resistance are needed to estimate the prognosis of the disease and find better drug targets. miRNAs that were differentially expressed in Taxol-resistant ovarian cancer cells, compared with Taxol-sensitive cells, were screened by Illumina Human MicroRNA Expression BeadChips. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to identify target genes of selected miRNAs. Kaplan–Meier survival analysis was applied to identify dysregulated miRNAs in ovarian cancer patients using data from The Cancer Genome Atlas. A total of 82 miRNAs were identified in ovarian carcinoma cells compared to normal ovarian cells. miR-141, miR-106a, miR-200c, miR-96, and miR-378 were overexpressed, and miR-411, miR-432, miR-494, miR-409-3p, and miR-655 were underexpressed in ovarian cancer cells. Seventeen miRNAs were overexpressed in Taxol-resistant cells, including miR-663, miR-622, and HS_188. Underexpressed miRNAs in Taxol-sensitive cells included miR-497, miR-187, miR-195, and miR-107. We further showed miR-663 and miR-622 as significant prognosis markers of the chemo-resistant patient group. In particular, the downregulation of the two miRNAs was associated with better survival, perhaps increasing the sensitivity of cancer cells to Taxol. In the chemo-sensitive patient group, only miR-647 could be a prognosis marker. These miRNAs inhibit several interacting genes of p53 networks, especially in TUOS-3 and TUOS-4, and showed cell line-specific inhibition effects. Taken together, the data indicate that the three miRNAs are closely associated with Taxol resistance and potentially better prognosis factors. Our results suggest that these miRNAs were successfully and reliably identified and would be used in the development of miRNA therapies in treating ovarian cancer. PMID:24591819

  19. Three-step tumor targeting of paclitaxel using biotinylated PLA-PEG nanoparticles and avidin-biotin technology: Formulation development and in vitro anticancer activity.

    PubMed

    Pulkkinen, Mika; Pikkarainen, Jere; Wirth, Thomas; Tarvainen, Tommy; Haapa-aho, Vesa; Korhonen, Harri; Seppälä, Jukka; Järvinen, Kristiina

    2008-09-01

    Despite recent advances in cancer therapy, many malignant tumors still lack effective treatment and the prognosis is very poor. Paclitaxel is a potential anticancer drug, but its use is limited by the facts that paclitaxel is a P-gp substrate and its aqueous solubility is poor. In this study, three-step tumor targeting of paclitaxel using biotinylated PLA-PEG nanoparticles and avidin-biotin technology was evaluated in vitro as a way of enhancing delivery of paclitaxel. Paclitaxel was incorporated both in biotinylated (BP) and non-biotinylated (LP) PEG-PLA nanoparticles by the interfacial deposition method. Small (mean size approximately 110 nm), spherical and slightly negatively charged (-10 mV) BP and LP nanoparticles achieving over 90% paclitaxel incorporation were obtained. The successful biotinylation of nanoparticles was confirmed in a novel streptavidin assay. BP nanoparticles were targeted in vitro to brain tumor (glioma) cells (BT4C) by three-step avidin-biotin technology using transferrin as the targeting ligand. The three-step targeting procedure increased the anti-tumoral activity of paclitaxel when compared to the commercial paclitaxel formulation Taxol and non-targeted BP and LP nanoparticles. These results indicate that the efficacy of paclitaxel against tumor cells can be increased by this three-step targeting method. PMID:18555675

  20. Prodrug Strategies for Paclitaxel

    PubMed Central

    Meng, Ziyuan; Lv, Quanxia; Lu, Jun; Yao, Houzong; Lv, Xiaoqing; Jiang, Feng; Lu, Aiping; Zhang, Ge

    2016-01-01

    Paclitaxel is an anti-tumor agent with remarkable anti-tumor activity and wide clinical uses. However, it is also faced with various challenges especially for its poor water solubility and low selectivity for the target. To overcome these disadvantages of paclitaxel, approaches using small molecule modifications and macromolecule modifications have been developed by many research groups from all over the world. In this review, we discuss the different strategies especially prodrug strategies that are currently used to make paclitaxel more effective. PMID:27223283

  1. Synergy of Taxol and radioimmunotherapy with yttrium-90-labeled chimeric L6 antibody: Efficacy and toxicity in breast cancer xenografts

    PubMed Central

    DeNardo, Sally J.; Kukis, David L.; Kroger, Linda A.; O’Donnell, Robert T.; Lamborn, Kathleen R.; Miers, Laird A.; DeNardo, David G.; Meares, Claude F.; DeNardo, Gerald L.

    1997-01-01

    Synergistic multimodality therapy is needed for breast cancer. Breast cancer frequently has p53 mutations that result in cells less likely to undergo apoptosis when exposed to DNA damaging therapies. Taxol (paclitaxel) is more effective in the presence of mutant p53. 90Y-labeled DOTA-peptide-ChL6 (90Y-ChL6, where ChL6 is chimeric L6 antibody and DOTA is 1,4,7,10-tetraazacyclododecane-N,N′,N",N‴-tetraacetic acid) is a novel radioimmunoconjugate for targeting radiation to cancer. It has a stable metal chelator and a peptide linker that can be catabolized by hepatic lysozymes. This study was designed to assess potential synergism between Taxol and 90Y-ChL6 in a highly anaplastic breast cancer model, HBT 3477. There was no tumor response in mice receiving ChL6 or Taxol alone. In mice receiving 90Y-ChL6 alone, 79% (15 of 19) of tumors responded although none were cured. If Taxol was administered 24–72 hours before 90Y-ChL6, again, 79% (23 of 29) of tumors responded but 21% were cured. When Taxol was administered 6 or 24 hours after 90Y-ChL6, 100% (46 of 46) of tumors responded and 48% were cured. Taxol given with 90Y-ChL6 did not substantially increase toxicity. Enhancement of the therapeutic effect when Taxol was added to 90Y-ChL6 therapy for HBT 3477 xenografts was striking. The synergistic therapeutic effect of Taxol with 90Y-ChL6 may relate to the p53 mutant status and BCL2 expression in HBT 3477 cells, observations that increase the likelihood that the results of this study are relevant to therapy for breast cancer in patients. In conclusion, Taxol seemed to be synergistic with 90Y-ChL6 in this human breast cancer model. Up to 50% of these anaplastic breast cancer xenografts were cured by combined modality therapy. PMID:9108094

  2. Moderate intensity static magnetic fields affect mitotic spindles and increase the antitumor efficacy of 5-FU and Taxol.

    PubMed

    Luo, Yan; Ji, Xinmiao; Liu, Juanjuan; Li, Zhiyuan; Wang, Wenchao; Chen, Wei; Wang, Junfeng; Liu, Qingsong; Zhang, Xin

    2016-06-01

    Microtubules are the fundamental components in mitotic spindle, which plays essential roles in cell division. It was well known that purified microtubules could be affected by static magnetic fields (SMFs) in vitro because of the diamagnetic anisotropy of tubulin. However, whether these effects lead to cell division defects was unknown. Here we find that 1T SMFs induce abnormal mitotic spindles and increase mitotic index. Synchronization experiments show that SMFs delay cell exit from mitosis and cause mitotic arrest. These mimic the cellular effects of a microtubule-targeting drug Paclitaxel (Taxol), which is frequently used in combination with 5-Fluorouracil (5-FU) and Cisplatin in cancer treatment. Using four different human cancer cell lines, HeLa, HCT116, CNE-2Z and MCF7, we find that SMFs increase the antitumor efficacy of 5-FU or 5-FU/Taxol, but not Cisplatin, which indicates that the SMF-induced combinational effects with chemodrugs are drug-specific. Our study not only reveals the effect of SMFs on microtubules to cause abnormal mitotic spindles and delay cells exit from mitosis, but also implies the potential applications of SMFs in combination with chemotherapy drugs 5-FU or 5-FU/Taxol, but not with Cisplatin in cancer treatment. PMID:26775206

  3. AC1MMYR2 impairs high dose paclitaxel-induced tumor metastasis by targeting miR-21/CDK5 axis.

    PubMed

    Ren, Yu; Zhou, Xuan; Yang, Juan-Juan; Liu, Xia; Zhao, Xiao-hui; Wang, Qi-xue; Han, Lei; Song, Xin; Zhu, Zhi-yan; Tian, Wei-ping; Zhang, Lun; Mei, Mei; Kang, Chun-sheng

    2015-07-01

    Paclitaxel (taxol) is a widely used chemo-drug for many solid tumors, while continual taxol treatment is revealed to stimulate tumor dissemination. We previously found that a small molecule inhibitor of miR-21, termed AC1MMYR2, had the potential to impair tumorigenesis and metastasis. The aim of this study was to investigate whether combining AC1MMYR2 with taxol could be explored as a means to limit tumor metastasis. Here we showed that abnormal activation of miR-21/CDK5 axis was associated with breast cancer lymph node metastasis, which was also contribute to high dose taxol-induced invasion and epithelial mesenchymal transition (EMT) in both breast cancer cell line MDA-MB-231 and glioblastoma cell line U87VIII. AC1MMYR2 attenuated CDK5 activity by functional targeting CDK5RAP1, CDK5 activator p39 and target p-FAK(ser732). A series of in vitro assays indicated that treatment of AC1MMYR2 combined with taxol suppressed tumor migration and invasion ability in both MDA-MB-231 and U87VIII cell. More importantly, combination therapy impaired high-dose taxol induced invadopodia, and EMT markers including ?-catenin, E-cadherin and vimentin. Strikingly, a significant reduction of lung metastasis in mice was observed in the AC1MMYR2 plus taxol treatment. Taken together, our work demonstrated that AC1MMYR2 appeared to be a promising strategy in combating taxol induced cancer metastasis by targeting miR-21/CDK5 axis, which highlighted the potential for development of therapeutic modalities for better clinic taxol application. PMID:25827073

  4. From taxol to Taxol: the changing identities and ownership of an anti-cancer drug.

    PubMed

    Walsh, Vivien; Goodman, Jordan

    2002-01-01

    This paper analyzes the emergence and evolution of taxol, the world's bestselling anti-cancer drug. Over the years taxol has changed its identity, its status as property, and its association with different places (from the old-growth forests of Washington State to the government agencies of Washington, D.C., to laboratories in France). Taxol is not only a profitable pharmaceutical commodity and a substance injected into women with breast and/or ovarian cancer; it is also a natural product found in the bark of Taxus brevifolia (the Pacific yew, which is native to the North American Pacific Northwest) and a chemical substance that was discovered and brought to the point of commercial production in the public sector. We explore its role in several controversies: the destruction of old-growth forests, public participation in policy making, and the privatization of intellectual property and its effect on the price of drugs. PMID:12458837

  5. Paclitaxel Through the Ages of Anticancer Therapy: Exploring Its Role in Chemoresistance and Radiation Therapy

    PubMed Central

    Barbuti, Anna Maria; Chen, Zhe-Sheng

    2015-01-01

    Paclitaxel (Taxol®) is a member of the taxane class of anticancer drugs and one of the most common chemotherapeutic agents used against many forms of cancer. Paclitaxel is a microtubule-stabilizer that selectively arrests cells in the G2/M phase of the cell cycle, and found to induce cytotoxicity in a time and concentration-dependent manner. Paclitaxel has been embedded in novel drug formulations, including albumin and polymeric micelle nanoparticles, and applied to many anticancer treatment regimens due to its mechanism of action and radiation sensitizing effects. Though paclitaxel is a major anticancer drug which has been used for many years in clinical treatments, its therapeutic efficacy can be limited by common encumbrances faced by anticancer drugs. These encumbrances include toxicities, de novo refraction, and acquired multidrug resistance (MDR). This article will give a current and comprehensive review of paclitaxel, beginning with its unique history and pharmacology, explore its mechanisms of drug resistance and influence in combination with radiation therapy, while highlighting current treatment regimens, formulations, and new discoveries. PMID:26633515

  6. PEG-derivatized octacosanol as micellar carrier for paclitaxel delivery.

    PubMed

    Chu, Bingyang; Qu, Ying; Huang, Yixing; Zhang, Lan; Chen, Xiaoxin; Long, Chaofeng; He, Yunqi; Ou, Caiwen; Qian, Zhiyong

    2016-03-16

    In this study, PEG-derivatized octacosanol copolymer was successfully developed to improve the anti-tumor activity and eliminate toxicity of the commercial formulation of paclitaxel (PTX). MPEG2K-C28, the conjugation of monomethoxy Poly(ethylene glycol) 2000 and octacosanol, was readily soluble in aqueous solution and self-assembled to form micelles with small sizes (<20nm) that are efficient in encapsulating PTX with a drug loading of 9.38±0.18% and an encapsulation efficiency of 93.90±2.12%. Meanwhile, octacosanol is very safe for humans and amazingly exhibits antitumor activity through inhibition activity of matrix metalloproteinases (MMPs) and translocation of the transcription factor (nuclear factor-kappa B, NF-κB) to the nucleus, which may be able to promote synergistic effects with PTX. A sustained and slower in vitro release behavior was observed in the (PTX micelles) than that of Taxol. PTX micelles exhibited more potent cytotoxicity than Taxol in the 4T1 breast cancer cell line. More interestingly, MPEG2K-C28 selectively inhibited the growth of 4T1 cells rather than the normal cells (HEK293 and L929 cell lines), indicating the antitumor activity of octacosanol remained after conjugation with MPEG. Acute toxicity evaluations indicated that MPEG2K-C28 was a safe drug carrier. Pharmacokinetic study revealed that PTX micelles improved the T1/2 and AUC of PTX (compared with Taxol) from 1.910±0.139h and 13.999±1.109mg/l×h to 2.876±0.532h and 76.462±8.619mg/l×h in vivo, respectively. The maximal tolerated dose (MTD) for PTX micelles (ca. 120mg PTX/kg) in mice was significantly higher than that for Taxol (ca. 20mg PTX/kg). PTX micelles exhibited slightly better antitumor activity than Taxol but safer in 4T1 breast cancer model in vivo. The cell apoptosis in the immunofluorescent studies and the cell proliferation in the immunohistochemical studies also proved the results. In conclusion, MPEG2K-C28 is a simple, safe and effective drug delivery carrier for PTX, and has some therapeutic effects in 4T1 cells in vitro. PTX micelles showed significant antitumor activity in vivo with low systemic toxicity in 4T1 breast cancer. MPEG2K-C28 micelles entrapping PTX deserve more studies in the future. PMID:26794876

  7. In vitro efficacy of paclitaxel-loaded dual-responsive shell cross-linked polymer nanoparticles having orthogonally degradable disulfide cross-linked corona and polyester core domains.

    PubMed

    Samarajeewa, Sandani; Shrestha, Ritu; Elsabahy, Mahmoud; Karwa, Amolkumar; Li, Ang; Zentay, Ryan P; Kostelc, James G; Dorshow, Richard B; Wooley, Karen L

    2013-03-01

    Paclitaxel-loaded shell cross-linked polymeric nanoparticles having an enzymatically and hydrolytically degradable poly(lactic acid) core and a glutathione-responsive disulfide cross-linked poly(oligoethylene glycol)-containing corona were constructed in aqueous solution and investigated for their stimuli-responsive release of the embedded therapeutics and in vitro cytotoxicity. Paclitaxel release from the nanoparticles in PBS buffer was accelerated in the presence of glutathione at both pH 5.5 and pH 7.4, reaching ca. 65% cumulative drug release after 8 d, whereas only ca. 50% and 35% extents of release were observed in the absence of glutathione at pH 5.5 and pH 7.4, respectively. Enzyme-catalyzed hydrolysis of the nanoparticle core resulted in the degradation of ca. 30% of the poly(lactic acid) core to lactic acid within 12 h, with coincidently triggered paclitaxel release of ca. 37%, as opposed to only ca. 17% release from the uncatalyzed nanoparticles at pH 7.4. While empty nanoparticles did not show any inherent cytotoxicity at the highest tested concentrations, paclitaxel-loaded nanoparticles showed IC50 values that were similar to those of free paclitaxel at 72 h incubation with KB cells and were more efficacious at ca. 3-fold lower IC50 value (0.031 μM vs 0.085 μM) at 2 h of incubation. Against human ovarian adenocarcinoma cells, the paclitaxel-loaded nanoparticles exhibited a remarkable ca. 11-fold lower IC50 than a Taxol-mimicking formulation (0.0007 μM vs 0.008 μM) at 72 h of incubation. These tunable dual-responsive degradable nanoparticles show great promise for delivery of paclitaxel to tumor tissues, given their superior in vitro efficacies compared to that of free paclitaxel and Taxol-mimicking formulations. PMID:23421959

  8. Elevated AKAP12 in Paclitaxel-Resistant Serous Ovarian Cancer Cells is Prognostic and Predictive of Poor Survival in Patients

    PubMed Central

    Bateman, Nicholas W.; Jaworski, Elizabeth; Ao, Wei; Wang, Guisong; Litzi, Tracy; Dubil, Elizabeth; Marcus, Charlotte; Conrads, Kelly A.; Teng, Pang-ning; Hood, Brian L.; Phippen, Neil T.; Vasicek, Lisa A.; McGuire, William P.; Paz, Keren; Sidransky, David; Hamilton, Chad A.; Maxwell, G. Larry; Darcy, Kathleen M.; Conrads, Thomas P.

    2015-01-01

    A majority of high-grade (HG) serous ovarian cancer (SOC) patients develop resistant disease despite high initial response rates to platinum/paclitaxel-based chemotherapy. We identified shed/secreted proteins in preclinical models of paclitaxel-resistant human HGSOC models and correlated these candidate proteins with patient outcomes using public data from HGSOC patients. Proteomic analyses of a HGSOC cell line secretome was compared to those from a syngeneic paclitaxel-resistant variant and from a line established from an intrinsically chemorefractory HGSOC patient Associations between the identified candidate proteins and patient outcome were assessed in a discovery cohort of 545 patients and two validation cohorts totaling 795 independent SOC patients. Among the 81 differentially abundant proteins identified (q < 0.05) from paclitaxel-sensitive vs -resistant HGSOC cell secretomes, AKAP12 was verified to be elevated in all models of paclitaxel-resistant HGSOC. Furthermore, elevated AKAP12 transcript expression was associated with worse progression-free and overall survival. Associations with outcome were observed in three independent cohorts and remained significant after adjusted multivariate modeling. We further provide evidence to support that differential gene methyktion status is associated with elevated expression of AKAP12 in taxol-resistant ovarian cancer cells and ovarian cancer patient subsets. Elevated expression and shedding/secretion of AKAP12 is characteristic of paclitaxel-resistant HGSOC cells, and elevated AKAP12 transcript expression is a poor prognostic and predictive marker for progression-free and overall survival in SOC patients. PMID:25748058

  9. Elevated AKAP12 in paclitaxel-resistant serous ovarian cancer cells is prognostic and predictive of poor survival in patients.

    PubMed

    Bateman, Nicholas W; Jaworski, Elizabeth; Ao, Wei; Wang, Guisong; Litzi, Tracy; Dubil, Elizabeth; Marcus, Charlotte; Conrads, Kelly A; Teng, Pang-ning; Hood, Brian L; Phippen, Neil T; Vasicek, Lisa A; McGuire, William P; Paz, Keren; Sidransky, David; Hamilton, Chad A; Maxwell, G Larry; Darcy, Kathleen M; Conrads, Thomas P

    2015-04-01

    A majority of high-grade (HG) serous ovarian cancer (SOC) patients develop resistant disease despite high initial response rates to platinum/paclitaxel-based chemotherapy. We identified shed/secreted proteins in preclinical models of paclitaxel-resistant human HGSOC models and correlated these candidate proteins with patient outcomes using public data from HGSOC patients. Proteomic analyses of a HGSOC cell line secretome was compared to those from a syngeneic paclitaxel-resistant variant and from a line established from an intrinsically chemorefractory HGSOC patient. Associations between the identified candidate proteins and patient outcome were assessed in a discovery cohort of 545 patients and two validation cohorts totaling 795 independent SOC patients. Among the 81 differentially abundant proteins identified (q < 0.05) from paclitaxel-sensitive vs -resistant HGSOC cell secretomes, AKAP12 was verified to be elevated in all models of paclitaxel-resistant HGSOC. Furthermore, elevated AKAP12 transcript expression was associated with worse progression-free and overall survival. Associations with outcome were observed in three independent cohorts and remained significant after adjusted multivariate modeling. We further provide evidence to support that differential gene methylation status is associated with elevated expression of AKAP12 in taxol-resistant ovarian cancer cells and ovarian cancer patient subsets. Elevated expression and shedding/secretion of AKAP12 is characteristic of paclitaxel-resistant HGSOC cells, and elevated AKAP12 transcript expression is a poor prognostic and predictive marker for progression-free and overall survival in SOC patients. PMID:25748058

  10. Radiation and taxol effects on synchronized human cervical carcinoma cells

    SciTech Connect

    Geard, C.R.; Jones, J.M. )

    1994-06-15

    The purpose was to evaluate the effectiveness of the plant derived chemotherapeutic agent taxol alone and in combination with ionizing radiation on synchronous and asynchronous human cervical carcinoma cells and to define the mechanistic basis for this cytotoxic response. Asynchronous and synchronous cells (obtained by modified mitotic shake-off) derived from carcinomas of the human uterine cervix were treated with a range of concentrations of taxol (0, 1.0, 2.5, 5.0, 10.0, and 20.0 nM) for either 8, 24, or 48 h. Synchronized cell cycling was evaluated by counting mitotic indices and by uptake of bromodeoxyuridine (BrdUrd). Cells were irradiated ([sup 137]Cs [gamma] rays at 1.12 Gy/min) alone and after taxol treatment and plating efficiencies and radiosensitivity determined. Taxol treatment resulted in a dose time dependent loss of colony forming ability with 10 nM for 24 h producing about 10% cell survival. Irradiating taxol treated cells resulted in a strictly additive response in contrast to previous supra-additive results with astrocytoma and melanoma cells. Mitotically synchronized cells rapidly moved into G[sub 1] phase with a second mitotic peak at 28 h (total cycle time). Taxol treatment resulted in a continued accumulation of mitoses, and a failure and/or delay of entry of a fraction of cells into S phase after a G[sub 1] phase of at least 10 h. That is, taxol effects cell cycling at a stage other than G[sub 2]/M. Irradiating (3 Gy) synchronized cells showed a 10-fold variation in sensitivity, with mitosis as the most sensitive phase with taxol alone resulting in some cytotoxicity and combined effects additive or less than additive. This may explain the failure to obtain taxol radiosensitization with these cells and it may indicate that taxol has a multiplicity of actions with differences in effectiveness likely between cells of different origins. 24 refs., 5 figs.

  11. Increased Spinal Cord Na+-K+-2Cl− Cotransporter-1 (NKCC1) Activity Contributes to Impairment of Synaptic Inhibition in Paclitaxel-induced Neuropathic Pain*

    PubMed Central

    Chen, Shao-Rui; Zhu, Lihong; Chen, Hong; Wen, Lei; Laumet, Geoffroy; Pan, Hui-Lin

    2014-01-01

    Microtubule-stabilizing agents, such as paclitaxel (Taxol), are effective chemotherapy drugs for treating many cancers, and painful neuropathy is a major dose-limiting adverse effect. Cation-chloride cotransporters, such as Na+-K+-2Cl− cotransporter-1 (NKCC1) and K+-Cl− cotransporter-2 (KCC2), critically influence spinal synaptic inhibition by regulating intracellular chloride concentrations. Here we show that paclitaxel treatment in rats significantly reduced GABA-induced membrane hyperpolarization and caused a depolarizing shift in GABA reversal potential of dorsal horn neurons. However, paclitaxel had no significant effect on AMPA or NMDA receptor-mediated glutamatergic input from primary afferents to dorsal horn neurons. Paclitaxel treatment significantly increased protein levels, but not mRNA levels, of NKCC1 in spinal cords. Inhibition of NKCC1 with bumetanide reversed the paclitaxel effect on GABA-mediated hyperpolarization and GABA reversal potentials. Also, intrathecal bumetanide significantly attenuated hyperalgesia and allodynia induced by paclitaxel. Co-immunoprecipitation revealed that NKCC1 interacted with β-tubulin and β-actin in spinal cords. Remarkably, paclitaxel increased NKCC1 protein levels at the plasma membrane and reduced NKCC1 levels in the cytosol of spinal cords. In contrast, treatment with an actin-stabilizing agent had no significant effect on NKCC1 protein levels in the plasma membrane or cytosolic fractions of spinal cords. In addition, inhibition of the motor protein dynein blocked paclitaxel-induced subcellular redistribution of NKCC1, whereas inhibition of kinesin-5 mimicked the paclitaxel effect. Our findings suggest that increased NKCC1 activity contributes to diminished spinal synaptic inhibition and neuropathic pain caused by paclitaxel. Paclitaxel disrupts intracellular NKCC1 trafficking by interfering with microtubule dynamics and associated motor proteins. PMID:25253692

  12. Preclinical Evaluation of Genexol-PM, a Nanoparticle Formulation of Paclitaxel, as a Novel Radiosensitizer for the Treatment of Non-Small Cell Lung Cancer

    SciTech Connect

    Werner, Michael E.; Cummings, Natalie D.; Sethi, Manish; Wang, Edina C.; Sukumar, Rohit; Carolina Center for Cancer Nanotechnology Excellence, University of North Carolina-Chapel Hill, Chapel Hill, North Carolina ; Moore, Dominic T.; Wang, Andrew Z.

    2013-07-01

    Purpose: A key research objective in radiation oncology is to identify agents that can improve chemoradiation therapy. Nanoparticle (NP) chemotherapeutics possess several properties, such as preferential accumulation in tumors, that are uniquely suited for chemoradiation therapy. To facilitate the clinical translation of NP chemotherapeutics in chemoradiation therapy, we conducted preclinical evaluation of Genexol-PM, the only clinically approved NP chemotherapeutic with a controlled drug release profile, as a radiosensitizer using non-small cell lung cancer (NSCLC) as a model disease. Methods and Materials: The physical characteristics and drug release profile of Genexol-PM were characterized. Genexol-PM's efficacy as a radiosensitizer was evaluated in vitro using NSCLC cell lines and in vivo using mouse xenograft models of NSCLC. Paclitaxel dose to normal lung and liver after Genexol-PM administration were quantified and compared with that after Taxol administration. Results: Genexol-PM has a size of 23.91 ± 0.41 nm and surface charge of −8.1 ± 3.1 mV. It releases paclitaxel in a controlled release profile. In vitro evaluation of Genexol-PM as a radiosensitizer showed it is an effective radiosensitizer and is more effective than Taxol, its small molecule counterpart, at the half maximal inhibitory concentration. In vivo study of Genexol-PM as a radiosensitizer demonstrated that it is more effective as a radiosensitizer than Taxol. We also found that Genexol-PM leads to lower paclitaxel exposure to normal lung tissue than Taxol at 6 hours postadministration. Conclusions: We have demonstrated that Genexol-PM is more effective than Taxol as a radiosensitizer in the preclinical setting and holds high potential for clinical translation. Our data support the clinical evaluation of Genexol-PM in chemoradiation therapy for NSCLC.

  13. Preparation and characterization of paclitaxel nanosuspension using novel emulsification method by combining high speed homogenizer and high pressure homogenization.

    PubMed

    Li, Yong; Zhao, Xiuhua; Zu, Yuangang; Zhang, Yin

    2015-07-25

    The aim of this study was to develop an alternative, more bio-available, better tolerated paclitaxel nanosuspension (PTXNS) for intravenous injection in comparison with commercially available Taxol(®) formulation. In this study, PTXNS was prepared by emulsification method through combination of high speed homogenizer and high pressure homogenization, followed by lyophilization process for intravenous administration. The main production parameters including volume ratio of organic phase in water and organic phase (Vo:Vw+o), concentration of PTX, content of PTX and emulsification time (Et), homogenization pressure (HP) and passes (Ps) for high pressure homogenization were optimized and their effects on mean particle size (MPS) and particle size distribution (PSD) of PTXNS were investigated. The characteristics of PTXNS, such as, surface morphology, physical status of paclitaxel (PTX) in PTXNS, redispersibility of PTXNS in purified water, in vitro dissolution study and bioavailability in vivo were all investigated. The PTXNS obtained under optimum conditions had an MPS of 186.8 nm and a zeta potential (ZP) of -6.87 mV. The PTX content in PTXNS was approximately 3.42%. Moreover, the residual amount of chloroform was lower than the International Conference on Harmonization limit (60 ppm) for solvents. The dissolution study indicated PTXNS had merits including effect to fast at the side of raw PTX and sustained-dissolution character compared with Taxol(®) formulation. Moreover, the bioavailability of PTXNS increased 14.38 and 3.51 times respectively compared with raw PTX and Taxol(®) formulation. PMID:26027492

  14. Caveolin-1 regulates cell apoptosis and invasion ability in paclitaxel-induced multidrug-resistant A549 lung cancer cells

    PubMed Central

    Han, Fei; Zhang, Long; Zhou, Yongxin; Yi, Xianghua

    2015-01-01

    The aim of the study was to investigate the effect and potential mechanism of caveolin-1 (Cav1) knockdown in paclitaxel-resistant lung cancer A549/Taxol cells. The human paclitaxel-resistant lung cancer cell line A549/Taxol was transfected with a Cav1 shRNA lentiviral vector. Interference efficiency for Cav1 was detected by real-time PCR and Western blotting. A MTT assay was used to determine cell proliferation, and flow cytometry was used to detect the cell cycle stage and apoptosis. Cell migration and invasion capability were detected by a transwell assay. Protein levels of related signaling molecules were detected by Western blotting. We successfully constructed a stable A549/Taxol cell line expressing low levels of Cav1. Cav1 knockdown significantly inhibited cell proliferation and induced G0/G1 arrest and cell apoptosis in vitro and in vivo. In addition, these effects correlated significantly with a reduction in cyclin D1 expression and activation of the Bcl-2/Bax-mediated mitochondrial apoptosis pathway. Furthermore, knockdown of Cav1 inhibited cell migration and invasion, and this may be related to the inhibition of AKT and the subsequent decreased protein expression of MMP2, MMP7 and MMP9. PMID:26464635

  15. Caveolin-1 tyrosine phosphorylation enhances paclitaxel-mediated cytotoxicity.

    PubMed

    Shajahan, Ayesha N; Wang, Aifen; Decker, Markus; Minshall, Richard D; Liu, Minetta C; Clarke, Robert

    2007-02-23

    Caveolin-1 (CAV1), a highly conserved membrane-associated protein, is a putative regulator of cellular transformation. CAV1 is localized in the plasmalemma, secretory vesicles, Golgi, mitochondria, and endoplasmic reticulum membrane and associates with the microtubule cytoskeleton. Taxanes such as paclitaxel (Taxol) are potent anti-tumor agents that repress the dynamic instability of microtubules and arrest cells in the G(2)/M phase. Src phosphorylation of Tyr-14 on CAV1 regulates its cellular localization and function. We report that phosphorylation of CAV1 on Tyr-14 regulates paclitaxel-mediated apoptosis in MCF-7 breast cancer cells. Befitting its role as a multitasking molecule, we show that CAV1 sensitizes cells to apoptosis by regulating cell cycle progression and activation of the apoptotic signaling molecules BCL2, p53, and p21. We demonstrate that phosphorylated CAV1 triggers apoptosis by inactivating BCL2 and increasing mitochondrial permeability more efficiently than non-phosphorylated CAV1. Furthermore, expression of p21, which correlates with taxane sensitivity, is regulated by CAV1 phosphorylation in a p53-dependent manner. Collectively, our findings underscore the importance of CAV1 phosphorylation in apoptosis and suggest that events that negate CAV1 tyrosine phosphorylation may contribute to anti-microtubule drug resistance. PMID:17190831

  16. Modulation of septin and molecular motor recruitment in the microtubule environment of the Taxol-resistant human breast cancer cell line MDA-MB-231.

    PubMed

    Froidevaux-Klipfel, Laurence; Poirier, Florence; Boursier, Céline; Crépin, Ronan; Poüs, Christian; Baudin, Bruno; Baillet, Anita

    2011-10-01

    Cell resistance to low doses of paclitaxel (Taxol) involves a modulation of microtubule (MT) dynamics. We applied a proteomic approach based on 2-DE coupled with MS to identify changes in the MT environment of Taxol-resistant breast cancer cells. Having established a proteomic pattern of the microtubular proteins extracted from MDA-MB-231 cells, we verified by Western blotting that in resistant cells, α- and β-tubulins (more specifically the βIII and βIV isotypes) increased. Interestingly, four septins (SEPT2, 8, 9 and 11), which are GTPases involved in cytokinesis and in MT/actin cytoskeleton organization, were overexpressed and enriched in the MT environment of Taxol-resistant cells compared to their sensitive counterpart. Changes in the MT proteome of resistant cells also comprised increased kinesin-1 heavy chain expression and recruitment on MTs while dynein light chain-1 was downregulated. Modulation of motor protein recruitment around MTs might reflect their important role in controlling MT dynamics via the organization of signaling pathways. The identification of proteins previously unknown to be linked to taxane-resistance could also be valuable to identify new biological markers of resistance. PMID:21761557

  17. Combination between Taxol-Encapsulated Liposomes and Eruca sativa Seed Extract Suppresses Mammary Tumors in Female Rats Induced by 7,12 Dimethylbenz(α)anthracene.

    PubMed

    Shaban, Nadia; Abdel-Rahman, Salah; Haggag, Amany; Awad, Doaa; Bassiouny, Ahmad; Talaat, Iman

    2016-01-01

    Taxol (paclitaxel) is a powerful anti-cancer drug widely used against several types of malignant tumors. Because Taxol may exert several side effects, a variety of formulations have been developed. One of these features liposomes, regarded as one of the most promising drug carriers, biocompatible and best able to reduce drug toxicity without changing efficacy against tumor cells. Eruca sativa seed extract (SE) is considered a promising natural product from cruciferous vegetables against breast cancer, increasing chemotherapeutic and eliminating harmful side effects. The effects of Taxol-encapsulated liposomes (T) alone and in combination between Eruca sativa seed extract on nuclear factor kappa B (NF-κB), cyclooxygenase-2 (COX-2) and B-cell lymphoma-2 (Bcl-2) gene expression levels were investigated in rat mammary gland carcinogenesis induced by 7,12 dimethylbenz(α) anthracene (DMBA) using qRT-PCR. The results showed that DMBA increased NF-κB, COX-2 and Bcl-2 gene expression levels and lipid peroxidation (LP), while decreasing glutathione-S-transferase (GST) and superoxide dismutase (SOD) activities and total antioxidant concentration (TAC) compared to the control group. T and T-SE treatment reduced NF-κB, COX-2 and Bcl-2 gene expression levels and LP. Hence, T and T-SE treatment appeared to reduce inflammation and cell proliferation, while increasing apoptosis, GST and SOD activities and TAC. PMID:26838195

  18. Hydrophobically modified inulin as an amphiphilic carbohydrate polymer for micellar delivery of paclitaxel for intravenous route.

    PubMed

    Muley, Pratik; Kumar, Sunny; El Kourati, Fadoua; Kesharwani, Siddharth S; Tummala, Hemachand

    2016-03-16

    Micellization offers several advantages for the delivery of water insoluble drugs including a nanoparticulate 'core-shell' delivery system for drug targeting. Recently, hydrophobically modified polysaccharides (HMPs) are gaining recognition as micelle forming polymers to encapsulate hydrophobic drugs. In this manuscript, for the first time, we have evaluated the self-assembling properties of a lauryl carbamate derivative of the poly-fructose natural polymer inulin (Inutec SP1(®) (INT)) to form paclitaxel (PTX) loaded micelles. INT self-assembled into well-defined micellar structures in aqueous environment with a low critical micellar concentration of 27.8μg/ml. INT micelles exhibited excellent hemocompatibility and low toxicity to cultured cells. PTX loaded INT micelles exhibited a mean size of 256.37±10.45nm with excellent drug encapsulation efficiency (95.66±2.25%) and loading (8.69±0.22%). PTX loaded micelles also displayed sustained release of PTX and enhanced anti-cancer efficacy in-vitro in mouse melanoma cells (B16F10) compared to Taxol formulation with Cremophor EL as solvent. In addition, PTX loaded INT micelles exhibited comparable in-vivo antitumor activity in B16F10 allograft mouse model at half the dose of Taxol. In conclusion, INT offers safe, inexpensive and natural alternative to widely used PEG-modified polymers for the formulation of micellar delivery systems for paclitaxel. PMID:26792170

  19. Phase behavior of dioleyphosphatidylethanolamine molecules in the presence of components of pH-sensitive liposomes and paclitaxel.

    PubMed

    Monteiro, Liziane O F; Lopes, Sávia C A; Barros, André Luís B; Magalhães-Paniago, Rogério; Malachias, Ângelo; Oliveira, Mônica C; Leite, Elaine A

    2016-08-01

    Paclitaxel is a potent antimicrotubule chemotherapeutic agent widely used for clinical treatment of a variety of solid tumors. However, the low solubility of the drug in aqueous medium and the toxic effects of the commercially available formulation, Taxol(®), has hindered its clinical application. To overcome these paclitaxel-related disadvantages, several drug delivery approaches have been thoroughly investigated. In this context, our research group has developed long-circulating and pHsensitive liposomes containing paclitaxel composed of dioleylphosphatidylethanolamine, cholesterylhemisuccinate and distearoylphosphatidylethanolamine-polyethylene glycol2000, which have shown to be very promising carriers for this taxane. For the destabilization of pH-sensitive liposomal systems and the release of the encapsulated drug in the cytoplasm of tumor cells, the occurrence of a phase transition from a lamellar to a non-lamellar phase of dioleylphosphatidylethanolamine molecules is essential. Two techniques, differential scanning calorimetry and small angle X-ray scattering, were used to investigate the influence of the liposomal components and paclitaxel in the phase transition process of dioleylphosphatidylethanolamine molecules and to evaluate the pH-sensitivity of the formulation under low hydration conditions. The findings clearly evidence the phase transition of dioleylphosphatidylethanolamine molecules in the presence and absence of PTX indicating that the introduction of the drug in the system does not bring damage to the pH-sensitivity of the system, which resulting in liposome destabilization at low pH regions and encapsulated paclitaxel release preferentially in a desired target tissue. PMID:27100854

  20. Identification and expression analysis of methyl jasmonate responsive ESTs in paclitaxel producing Taxus cuspidata suspension culture cells

    PubMed Central

    2012-01-01

    Background Taxol® (paclitaxel) promotes microtubule assembly and stabilization and therefore is a potent chemotherapeutic agent against wide range of cancers. Methyl jasmonate (MJ) elicited Taxus cell cultures provide a sustainable option to meet the growing market demand for paclitaxel. Despite its increasing pharmaceutical importance, the molecular genetics of paclitaxel biosynthesis is not fully elucidated. This study focuses on identification of MJ responsive transcripts in cultured Taxus cells using PCR-based suppression subtractive hybridization (SSH) to identify genes involved in global pathway control. Results Six separate SSH cDNA libraries of paclitaxel-accumulating Taxus cuspidata P991 cell lines were constructed at three different post-elicitation time points (6h, 18h and 5 day) to identify genes that are either induced or suppressed in response to MJ. Sequencing of 576 differentially screened clones from the SSH libraries resulted in 331 unigenes. Functional annotation and Gene Ontology (GO) analysis of up-regulated EST libraries showed enrichment of several known paclitaxel biosynthetic genes and novel transcripts that may be involved in MJ-signaling, taxane transport, or taxane degradation. Macroarray analysis of these identified genes unravelled global regulatory expression of these transcripts. Semi-quantitative RT-PCR analysis of a set of 12 candidate genes further confirmed the MJ-induced gene expression in a high paclitaxel accumulating Taxus cuspidata P93AF cell line. Conclusions This study elucidates the global temporal expression kinetics of MJ responsive genes in Taxus suspension cell culture. Functional characterization of the novel genes identified in this study will further enhance the understanding of paclitaxel biosynthesis, taxane transport and degradation. PMID:22530557

  1. Theoretical study on the reactive sites and intramolecular interactions in taxol and its four analogues

    NASA Astrophysics Data System (ADS)

    Zhou, Hongwei; Zhang, Zhiqiang; Cheung, Hon-Yeung

    A density-functional study of the paclitaxel (Taxol) molecule and its four analogues has been performed. The theory of Bader's atoms in molecules (AIM) was applied to examine the electronic structure of these molecules at their ground state. Topological analysis reveals that the esterification of hydroxyl group attached to the oxetane ring results in great change of conformation of the taxane ring, and thus is responsible for bioactivity of the oxetane oxygen atom. It was found that there exists some intramolecular interactions in the molecule, including normal hydrogen bonds (HBs) and double HBs. Visualization of the molecule shows that the central bodies (the four fused rings) of the molecules are wrapped by the intramolecular interactions. It is supposed that these intramolecular interactions lower the aqueous solubility and protect the flexible oxetane ring, which is regarded as the dominating bioactivity site of the drug, from being opened. Our results provide an extended and consistent set of data to gauge classical force fields in view of the atomistic investigations of the interaction of the bioactive molecules.

  2. Arginine-based molecular transporters: the synthesis and chemical evaluation of releasable taxol-transporter conjugates.

    PubMed

    Kirschberg, Thorsten A; VanDeusen, Chris L; Rothbard, Jonathan B; Yang, Michael; Wender, Paul A

    2003-09-18

    [structure: see text] A flexible and efficient procedure has been developed for the conjugation of taxol to various arginine-based molecular transporters via the taxol C2' O-chloroacetyl derivative. The resultant taxol-transporter conjugates are highly water soluble and release free taxol with half-lives of minutes to hours depending on the pH and the linker structure. PMID:12967299

  3. Jasmonate-responsive expression of paclitaxel biosynthesis genes in Taxus cuspidata cultured cells is negatively regulated by the bHLH transcription factors TcJAMYC1, TcJAMYC2, and TcJAMYC4

    PubMed Central

    Lenka, Sangram K.; Nims, N. Ezekiel; Vongpaseuth, Kham; Boshar, Rosemary A.; Roberts, Susan C.; Walker, Elsbeth L.

    2015-01-01

    Taxus cell suspension culture is a sustainable technology for the industrial production of paclitaxel (Taxol®), a highly modified diterpene anti-cancer agent. The methyl jasmonate (MJ)-mediated paclitaxel biosynthetic pathway is not fully characterized, making metabolic engineering efforts difficult. Here, promoters of seven genes (TASY, T5αH, DBAT, DBBT, PAM, BAPT, and DBTNBT), encoding enzymes of the paclitaxel biosynthetic pathway were isolated and used to drive MJ-inducible expression of a GUS reporter construct in transiently transformed Taxus cells, showing that elicitation of paclitaxel production by MJ is regulated at least in part at the level of transcription. The paclitaxel biosynthetic pathway promoters contained a large number of E-box sites (CANNTG), similar to the binding sites for the key MJ-inducible transcription factor AtMYC2 from Arabidopsis thaliana. Three MJ-inducible MYC transcription factors similar to AtMYC2 (TcJAMYC1, TcJAMYC2, and TcJAMYC4) were identified in Taxus. Transcriptional regulation of paclitaxel biosynthetic pathway promoters by transient over expression of TcJAMYC transcription factors indicated a negative rather than positive regulatory role of TcJAMYCs on paclitaxel biosynthetic gene expression. PMID:25767476

  4. Alterations in phosphatidylcholine synthesis are associated with taxol resistance

    SciTech Connect

    Sorbara, L.R.

    1986-01-01

    A taxol resistant variant (J7/TAX-50) of the murine macrophage-like cell line J774.2 has been developed in vitro. The LD/sub 50/ of taxol for the resistant cells is 800-fold greater than that for the parental cell line. The J7/TAX-50 cells display phenotypic traits which are associated with multidrug resistance. J7/TAX-50 is unstably resistant and must be maintained in the presence of taxol. Cells grown in the absence of taxol for 30 days revert to drug sensitivity, and the membrane phosphoglycoprotein is lost. In contrast, the return to a normal level of drug accumulation is prolonged and requires over 8 months of growth in the absence of taxol. To characterize further the parental, resistant and revertant cell lines, the major lipids have been analyzed by 2D-chromatography and HPLC. The steady-state level of phosphatidylcholine (PC) in J7/TAX-50 is greater than in the parental or revertant cell lines. Pulse-chase studies performed with /sup 14/C-choline or /sup 32/P-orthophosphate demonstrated an increase in the turnover of PC in J7/TAX-50. Analysis by gas chromatography/mass spectrometry of the composition of the major phospholipids indicated that fatty acids attached to the sn1- and 2-positions of PC are the same in the resistant and parental cell lines. These studies suggest that an increased level of PC in the membrane may be related to drug resistance and responsible for the prolonged decrease in steady-state drug association in J7/TAX-50 grown in the absence of taxol.

  5. Ab initio conformational study of the phenylisoserine side chain of paclitaxel.

    PubMed

    Milanesio, M; Ugliengo, P; Viterbo, D; Appendino, G

    1999-01-28

    Paclitaxel (Taxol) and related compounds are important antitumor drugs, currently used for the treatment of several types of cancer. The flexible amino acidic C13 side chain is a key element of the taxoid pharmacophore, and the identification of the bioactive conformation is a top priority for a better understanding of the mode of action of these anticancer agents. The conformational features of the side chain have been investigated by Hartree-Fock ab initio and semiempirical PM3 calculations. To gain a better understanding of solvent effects, different molecular models of paclitaxel were used in the calculations. The gas-phase calculations confirm that only one conformation, named ch1 (very similar to the one found in the crystal structure of docetaxel), is present in apolar environments. The preference for this conformer has been rationalized in terms of its L shape, which minimizes steric and Coulombic interactions, and of a favorable arrangement of the glycolate moiety. When a polar solvent was simulated by different methods, a greater conformational variability was found, with different conformations differing by less than 1.5 kcal/mol. Among these conformations, only one (ch5', similar to molecule B of the crystal structure of paclitaxel) is particularly apt to interact with solvent molecules. In light of these data, it seems reasonable to assume that, when the drug is bound to the lipophilic pocket of the tubuline receptor, the C13 amino acidic side chain assumes a conformation close to ch1. PMID:9925734

  6. Enzyme-instructed self-assembly of taxol promotes axonal branching

    NASA Astrophysics Data System (ADS)

    Mei, Bin; Miao, Qingqing; Tang, Anming; Liang, Gaolin

    2015-09-01

    Axonal branching is important for vertebrate neuron signaling. Taxol has a biphasic effect on axonal branching (i.e., high concentration inhibits axonal growth but low concentration restores it). To the best of our knowledge, low concentration of taxol to promote axonal branching has not been reported yet. Herein, we rationally designed a taxol derivative Fmoc-Phe-Phe-Lys(taxol)-Tyr(H2PO4)-OH (1) which could be subjected to alkaline phosphatase (ALP)-catalyzed self-assembly to form taxol nanofibers. We found that, at 10 μM, 1 has a microtubule (MT) condensation effect similar to that of taxol on mammalian cells but with more chronic toxicity than taxol on the cells. At a low concentration of 10 nM, 1 not only promoted neurite elongation as taxol did but also promoted axonal branching which was not achieved by using taxol. We propose that self-assembly of 1 along the MTs prohibited their lateral contacts and thus promoted axonal branching. Our strategy of enzyme-instructed self-assembly (EISA) of a taxol derivative provides a new tool for scientists to study the morphology of neurons, as well as their behaviours.Axonal branching is important for vertebrate neuron signaling. Taxol has a biphasic effect on axonal branching (i.e., high concentration inhibits axonal growth but low concentration restores it). To the best of our knowledge, low concentration of taxol to promote axonal branching has not been reported yet. Herein, we rationally designed a taxol derivative Fmoc-Phe-Phe-Lys(taxol)-Tyr(H2PO4)-OH (1) which could be subjected to alkaline phosphatase (ALP)-catalyzed self-assembly to form taxol nanofibers. We found that, at 10 μM, 1 has a microtubule (MT) condensation effect similar to that of taxol on mammalian cells but with more chronic toxicity than taxol on the cells. At a low concentration of 10 nM, 1 not only promoted neurite elongation as taxol did but also promoted axonal branching which was not achieved by using taxol. We propose that self-assembly of 1 along the MTs prohibited their lateral contacts and thus promoted axonal branching. Our strategy of enzyme-instructed self-assembly (EISA) of a taxol derivative provides a new tool for scientists to study the morphology of neurons, as well as their behaviours. Electronic supplementary information (ESI) available: Additional experimental details as described in the text. Synthetic routes for precursors and 1; Fig. S1-S10. See DOI: 10.1039/c5nr04563k

  7. Taxol-induced paraptosis-like A549 cell death is not senescence

    NASA Astrophysics Data System (ADS)

    Wang, Chao-yang; Chen, Tong-Sheng

    2011-03-01

    Our previous studies have shown that taxol, a potent anticancer agent, induces caspase-independent cell death and cytoplasmic vacuolization in human lung cancer cells. However, the mechanisms of taxol-induced cytoplasmic vacuolization are poorly understood. Cytoplasmic vacuolization have been reported to be a characteristic of cell senescence. Here, we employed confocal fluorescence microscopy imaging to study the reversibility of taxol-induced cytoplasmic vacuolization and whether taxol triggers senescence in A549 cells. We found that taxol-induced cytoplasmic vacuolization at 6 or 9 h after treatment with taxol did not decrease but increase at 24 h or 72 h after refreshing the culture medium without taxol, indicating taxol-induced cytoplasmic vacuolization is irreversible. We used SA-β-Gal (senescence-associated β-galactosidase) to assess whether taxol-induced cell death in cytoplasmic vacuolization fashion is senescence, and found that hydrogen peroxide (H2O2)-treated, but not taxol-treated cells is significantly stained by the SA-β-Gal, a senescence testing kit, indicating that the form of taxol-induced cell death is not senescence.

  8. Personal recollections on the early development of taxol.

    PubMed

    Horwitz, Susan Band

    2004-02-01

    All of us who have worked with taxol in the laboratory and the clinic, and the many patients all over the world who have benefited from the drug, owe a great debt of gratitude to Monroe Wall, Mansukh Wani, and their colleagues for the initial isolation and characterization of this compound. PMID:14987047

  9. Clinical phase I study of paclitaxel followed by cisplatin in advanced head and neck squamous cell carcinoma.

    PubMed

    Hanauske, A R; Schilling, T; Heinrich, B; Kau, R; Herzog, M; Quasthoff, S; Bochtler, H; Diergarten, K; Rastetter, J

    1995-12-01

    We performed a clinical phase I trial of the combination of paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) and cisplatin in patients with recurrent or metastatic squamous cell carcinoma of the head and neck, using a 3-hour infusion of paclitaxel followed by a 1-hour infusion of cisplatin. Treatment with this combination was repeated every 21 days. Patients who had received prior treatment with platinum-containing regimens were excluded. However, patients who had received two or fewer courses of radiochemotherapy not including platinum compounds were eligible. At present, 21 patients have been entered into this ongoing study. Doses ranged from paclitaxel 135 mg/m2 plus cisplatin 75 mg/m2 to paclitaxel 250 mg/m2 plus cisplatin 100 mg/m2. The maximum tolerated dose was reached at paclitaxel 250 mg/m2 and cisplatin 100 mg/m2. The dose-limiting toxicity of this regimen was myelosuppression (leukopenia, granulocytopenia). Clinically, neurosensory toxicity was moderate. However, preliminary analyses of threshold electrotonus studies indicate the presence of subclinical neurotoxicity in most patients. One patient receiving paclitaxel 200 mg/m2 plus cisplatin 100 mg/m2 developed grade 3 motor neurotoxicity. Profound orthostatic hypotension was observed in five patients receiving paclitaxel 200 mg/m2 plus cisplatin 100 mg/m2 or higher. Neurotoxicity was of delayed onset and slowly reversible, and its severity appeared to be dose related. Twelve patients are currently evaluable for response. Of these, three partial remissions were observed (6, 6+, and 3+ months). Five additional patients had stable disease. We conclude that the combination of paclitaxel administered as a 3-hour infusion followed by cisplatin is an active regimen in advanced head and neck cancer. In addition to myelosuppression, orthostatic hypotension may be a potentially significant clinical toxicity. Clinical phase II studies have been initiated, using a dose of paclitaxel 200 mg/m2 and cisplatin 100 mg/m2. PMID:8553082

  10. Polyelectrolyte multilayer nanoshells with hydrophobic nanodomains for delivery of Paclitaxel

    PubMed Central

    Jing, Jing; Guillot, Raphael; Paintrand, Isabelle; Auzely-Velty, Rachel; Picart, Catherine

    2014-01-01

    Efficient and effective delivery of poorly water-soluble drug molecules, which constitute a large part of commercially available drugs, is a major challenge in the field of drug delivery. Several drugs including paclitaxel (PTX) which are used for cancer treatment are hydrophobic, exhibit poor aqueous solubility and need to be delivered using an appropriate carrier. In the present work, we engineered Taxol-loaded polyelectrolyte films and microcapsules by pre-complexing PTX with chemically modified derivative of hyaluronic acid (alkylamino hydrazide) containing hydrophobic nanocavities, and subsequent assembly with either poly(L-lysine) (PLL) or quaternized chitosan (QCHI) as polycations. The PTX loading capacity of the films was found to be dependent on number of layers in the films as well as on the initial concentration of PTX pre-complexed to hydrophobic HA, with a loading capacity up to 5000-fold the initial PTX concentration. The films were stable in physiological medium and were degraded in the presence of hyaluronidase. The PTX-loaded microcapsules were found to decrease the viability and proliferation of MDA MB 231 breast cancer cells, while unloaded microcapsules did not impact cell viability. All together, our results highlight the potential of hyaluronan-based assemblies containing hydrophobic nanodomains for hydrophobic drug delivery. PMID:22300622

  11. Enhancement of taxol-induced apoptosis by inhibition of NF-κB with ursorlic acid

    NASA Astrophysics Data System (ADS)

    Li, Yunlong; Xing, Da

    2007-05-01

    Taxol is known to inhibit cell growth and triggers significant apoptosis in various cancer cells, and activation of proliferation factor NF-κB during Taxol-induced apoptosis is regarded as a main reason resulting in tumor cells resistance to Taxol. It has been found that ursorlic acid can inhibit the activation of NF-κB. In order to study whether ursorlic acid can enhance the Taxol-induced apoptosis, we use fluorescence resonance energy transfer (FRET) technique and probe SCAT3 to compare the difference of caspase-3 activation between Taxol alone and Taxol combined ursorlic acid. With laser scanning confocal microscopy, we find that ursorlic acid, a nontoxic food component, sensitizes ASTC-a-1 cells more efficiently to Taxol-induced apoptosis by advanced activation of caspase 3. The result also suggests that there would be a synergistic effect between Taxol and ursorlic acid, and the more detailed mechanism of synergistic effect needs to be clarified further, such as the correlations among NF-κB, Akt, caspase 8, which leads to the advanced activation of caspase 3 during combined treatment of Taxol and ursorlic acid. Moreover, this may be a new way to improve Taxol-dependent tumor therapy.

  12. Molecular and Morphological Characterization of a Taxol-Producing Endophytic Fungus, Gliocladium sp., from Taxus baccata

    PubMed Central

    Sushim, G. K.; Syed, A.; Khan, B. M.; Ahmad, A.

    2011-01-01

    The endophytic fungal populations of different tissues of Taxus baccata grown at high altitudes in West Bengal, India were explored. These isolated fungal populations represented different genera, which were screened for taxol production using immunoassay technique. The culture AAT-TS-41 that produced taxol was identified as Gliocladium sp. based on its cultural, morphological characteristics, internal transcribed spacer, and 18S rRNA sequence analysis. Kinetics of taxol production as a function of culture growth were investigated. PMID:22783096

  13. Role of Activating Transcription Factor 3 on TAp73 Stability and Apoptosis in Paclitaxel-Treated Cervical Cancer Cells

    PubMed Central

    Oh, Yeo Kyoung; Lee, Hyun Jung; Jeong, Mi-Hee; Rhee, Marie; Mo, Ji-Won; Song, Eun Hyeon; Lim, Joong-Yeon; Choi, Kyung-Hee; Jo, Inho; Park, Sang Ick; Gao, Bin; Kwon, Yongil; Kim, Won-Ho

    2013-01-01

    Taxol (paclitaxel) is a potent anticancer drug that has been found to be effective against several tumor types, including cervical cancer. However, the exact mechanism underlying the antitumor effects of paclitaxel is poorly understood. Here, paclitaxel induced the apoptosis of cervical cancer HeLa cells and correlated with the enhanced activation of caspase-3 and TAp73, which was strongly inhibited by TAp73β small interfering RNA (siRNA). In wild-type activating transcription factor 3 (ATF3)–overexpressed cells, paclitaxel enhanced apoptosis through increased α and β isoform expression of TAp73; however, these events were attenuated in cells containing inactive COOH-terminal–deleted ATF3 [ATF3(ΔC)] or ATF3 siRNA. In contrast, paclitaxel-induced ATF3 expression did not change in TAp73β -overexpressed or TAp73β siRNA–cotransfected cells. Furthermore, paclitaxel-induced ATF3 translocated into the nucleus where TAp73β is expressed, but not in ATF3 (ΔC) or TAp73β siRNA–transfected cells. As confirmed by the GST pull-down assay, ATF3 bound to the DNA-binding domain of p73, resulting in the activation of p21 or Bax transcription, a downstream target of p73. Overexpression of ATF3 prolonged the half-life of TAp73β by inhibiting its ubiquitination and thereby enhancing its transactivation and proapoptotic activities. Additionally, ATF3 induced by paclitaxel potentiated the stability of TAp73β, not its transcriptional level. Chromatin immunoprecipitation analyses show that TAp73β and ATF3 are recruited directly to the p21 and Bax promoter. Collectively, these results reveal that overexpression of ATF3 potentiates paclitaxel-induced apoptosis of HeLa cells, at least in part, by enhancing TAp73β's stability and its transcriptional activity. The investigation shows that ATF3 may function as a tumor-inhibiting factor through direct regulatory effects on TAp73β, suggesting a functional link between ATF3 and TAp73β. PMID:18644986

  14. Effects of spermine binding on Taxol-stabilized microtubules

    NASA Astrophysics Data System (ADS)

    Cheng, Shengfeng; Regmi, Chola

    Previous studies have shown that polyamines such as spermine present in cells at physiological concentrations can facilitate the polymerization of tubulins into microtubules (MTs). A recent experiment demonstrates that in the presence of high-concentration spermine, Taxol-stabilized MTs undergo a shape transformation into inverted tubulin tubules (ITTs), the outside surface of which corresponds to the inside surface of a regular MT. However, the molecular mechanism underlying the shape transformation of MTs into ITTs is unclear. We perform all atom molecular dynamics simulations on Taxol-stabilized MT sheets containing two protofilaments surrounded by spermine ions. The spermine concentration is varied from 0 to 25mM to match the range probed experimentally. We identify important spermine binding regions on the MT surface and the influence of the spermine binding on the structure and dynamics of MTs. In contrast to Taxol, our results show that spermine binding seems to decrease the flexibility of tubulin proteins, resulting in weaker tubulin-tubulin contacts and promoting the bending of protofilaments into curved protofilaments, inverted rings, and eventually inverted tubules.

  15. Engineering isoprenoid biosynthesis in Artemisia annua L. for the production of taxadiene: a key intermediate of taxol.

    PubMed

    Li, Meiya; Jiang, Fusheng; Yu, Xiangli; Miao, Zhiqi

    2015-01-01

    Taxadiene is the first committed precursor to paclitaxel, marketed as Taxol, arguably the most important anticancer agent against ovarian and breast cancer. In Taxus, taxadiene is directly synthesized from geranylgeranyl diphosphate (GGPP) that is the common precursor for diterpenoids and is found in most plants and microbes. In this study, Artemisia annua L., a Chinese medicinal herb that grows fast and is rich in terpenoids, was used as a genetic engineering host to produce taxadiene. The TXS (taxadiene synthase) gene, cloned from Taxus and inserted into pCAMBIA1304, was transformed into Artemisia annua L. using the Agrobacterium tumefaciens-mediated method. Thirty independent transgenic plants were obtained, and GC-MS analysis was used to confirm that taxadiene was produced and accumulated up to 129.7 μg/g dry mass. However, the high expression of TXS did not affect plant growth or photosynthesis in transgenic Artemisia annua L. It is notable that artemisinin is produced and stored in leaves and most taxadiene accumulated in the stem of transgenic Artemisia annua L., suggesting a new way to produce two important compounds in one transgenic plant: leaves for artemisinin and stem for taxadiene. Overall, this study demonstrates that genetic engineering of the taxane biosynthetic pathway in Artemisia annua L. for the production of taxadiene is feasible. PMID:25705665

  16. Engineering Isoprenoid Biosynthesis in Artemisia annua L. for the Production of Taxadiene: A Key Intermediate of Taxol

    PubMed Central

    Li, Meiya; Jiang, Fusheng; Yu, Xiangli; Miao, Zhiqi

    2015-01-01

    Taxadiene is the first committed precursor to paclitaxel, marketed as Taxol, arguably the most important anticancer agent against ovarian and breast cancer. In Taxus, taxadiene is directly synthesized from geranylgeranyl diphosphate (GGPP) that is the common precursor for diterpenoids and is found in most plants and microbes. In this study, Artemisia annua L., a Chinese medicinal herb that grows fast and is rich in terpenoids, was used as a genetic engineering host to produce taxadiene. The TXS (taxadiene synthase) gene, cloned from Taxus and inserted into pCAMBIA1304, was transformed into Artemisia annua L. using the Agrobacterium tumefaciens-mediated method. Thirty independent transgenic plants were obtained, and GC-MS analysis was used to confirm that taxadiene was produced and accumulated up to 129.7 μg/g dry mass. However, the high expression of TXS did not affect plant growth or photosynthesis in transgenic Artemisia annua L. It is notable that artemisinin is produced and stored in leaves and most taxadiene accumulated in the stem of transgenic Artemisia annua L., suggesting a new way to produce two important compounds in one transgenic plant: leaves for artemisinin and stem for taxadiene. Overall, this study demonstrates that genetic engineering of the taxane biosynthetic pathway in Artemisia annua L. for the production of taxadiene is feasible. PMID:25705665

  17. Cell-cycle synchronization reverses Taxol resistance of human ovarian cancer cell lines

    PubMed Central

    2013-01-01

    Background Taxol is a powerful chemotherapy agent leading to mitotic arrest and cell death; however, its clinical efficacy has been hampered due to the development of drug resistance. Taxol specifically targets the cell cycle. Progress through mitosis (M stage) is an absolute requirement for drug-induced death because cell death is markedly reduced in cells blocked at the G1-S transition. The measured doubling time for ovarian cancer cells is about 27 h. As such, during treatment with Taxol most of the cells are not in the M stage of the cell cycle. Thus, the effect of cell-cycle synchronization was investigated in regard to reversing Taxol resistance in ovarian cancer cells. Methods Giemsa-Wright staining was used for assessing the morphology of the cells. The doubling time of the cells was calculated using formula as follows: Td?=?In2/slope. The resistant index and cell cycle were measured via MTT assays and flow cytometry. Thymidine was used to induce cell-cycle synchronization, and cell apoptosis rates following exposure to Taxol were measured using a flow cytometer. Results The growth doubling time of two Taxol-resistant cell lines were longer than that of Taxol-sensitive cells. Apoptotic rates in Taxol-sensitive and -resistant cell lines after synchronization and exposure to Taxol were all higher compared to unsynchronized controls (p <0.05). Conclusions Synchronization of the cell-cycle resulted in an increased effectiveness of Taxol toward ovarian cancer cell lines. We speculated that formation of drug resistance toward Taxol in ovarian cancer could be partly attributed to the longer doubling time of these cells. PMID:23899403

  18. Synergy between paclitaxel plus an exogenous methyl donor in the suppression of murine demyelinating diseases.

    PubMed

    Mastronardi, F G; Tsui, H; Winer, S; Wood, D D; Selvanantham, T; Galligan, C; Fish, E N; Dosch, H-M; Moscarello, M A

    2007-06-01

    Progressive demyelination in multiple sclerosis (MS) reflects the negative balance between myelin damage and repair due to physical and molecular barriers, such as astrocytic glial scars, between oligodendrocytes and target neurons. In this paper, we show that combination therapy with paclitaxel (Taxol) plus the universal methyl-donor, vitamin B12CN (B12CN), dramatically limits progressive demyelination, and enhances remyelination in several independent, immune and nonimmune, in vivo and in vitro model systems. Combination therapy significantly reduced clinical signs of EAE in SJL mice, as well as the spontaneously demyelinating ND4 transgenic mouse. Astrocytosis was normalised in parallel to ultrastructural and biochemical evidence of remyelination. The combination therapy suppressed T cell expansion, reduced IFN-gamma, while enhancing IFN-beta and STAT-1 expression, STAT-1 phosphorylation and methylation of STAT-1 and MBP in the brain. Paclitaxel/B12CN has nearly identical effects to the previously described combination of IFN-beta/ B12CN, whose clinical usefulness is transient because of IFN-neutralising antibodies, not observed (or expected) with the present drug combination. This report provides a mechanistic foundation for the development of a new therapeutic strategy in humans with MS. PMID:17548438

  19. Novel thermo-sensitive core-shell nanoparticles for targeted paclitaxel delivery

    NASA Astrophysics Data System (ADS)

    Li, Yuanpei; Pan, Shirong; Zhang, Wei; Du, Zhuo

    2009-02-01

    Novel thermo-sensitive nanoparticles self-assembled from poly(N,N-diethylacrylamide- co-acrylamide)-block-poly(γ-benzyl L-glutamate) were designed for targeted drug delivery in localized hyperthermia. The lower critical solution temperature (LCST) of nanoparticles was adjusted to a level between physiological body temperature (37 °C) and that used in local hyperthermia (about 43 °C). The temperature-dependent performances of the core-shell nanoparticles were systemically studied by nuclear magnetic resonance (NMR), circular dichroism (CD), fluorescence spectroscopy, dynamic light scattering (DLS), and atom force microscopy (AFM). The mean diameter of the nanoparticles increased slightly from 110 to 129 nm when paclitaxel (PTX), a poorly water-soluble anti-tumor drug, was encapsulated. A stability study in bovine serum albumin (BSA) solution indicated that the PTX loaded nanoparticles may have a long circulation time under physiological environments as the LCST was above physiological body temperature and the shell remained hydrophilic at 37 °C. The PTX release profiles showed thermo-sensitive controlled behavior. The proliferation inhibiting activity of PTX loaded nanoparticles was evaluated against Hela cells in vitro, compared with Taxol (a formulation of paclitaxel dissolved in Cremophor EL and ethanol). The cytotoxicity of PTX loaded nanoparticles increased obviously when hyperthermia was performed. The nanoparticles synthesized here could be an ideal candidate for thermal triggered anti-tumor PTX delivery system.

  20. Cytotoxic and anti-angiogenic paclitaxel solubilized and permeation-enhanced by natural product nanoparticles

    PubMed Central

    Liu, Zhijun; Zhang, Fang; Koh, Gar Yee; Dong, Xin; Hollingsworth, Javoris; Zhang, Jian; Russo, Paul S.; Yang, Peiying; Stout, Rhett W.

    2014-01-01

    Paclitaxel (PTX) is one of the most potent intravenous chemotherapeutic agents to date, yet an oral formulation has been problematic due to its low solubility and permeability. Using the recently discovered solubilizing properties of rubusoside (RUB), we investigated this unique PTX-RUB formulation. Paclitaxel was solubilized by RUB in water to levels of 1.6 to 6.3 mg/mL at 10 to 40% weight/volume. These, nanomicellar, PTX-RUB complexes were dried to a powder which was subsequently reconstituted in physiologic solutions. After 2.5 hrs in gastric fluid 85 to 99% of PTX-RUB remained soluble, while 79 to 96% remained soluble in intestinal fluid. The solubilization of PTX was mechanized by the formation of water-soluble spherical nanomicelles between PTX and RUB with an average diameter of 6.6 nm. Compared with Taxol®, PTX-RUB nanoparticles were nearly four times more permeable in Caco-2 cell monocultures. In a side-by-side comparison with DMSO-solubilized PTX, PTX-RUB maintained the same level of cytotoxicity against three human cancer cell lines with IC50 values ranging from 4 nM to 20 nM. Additionally, tubular formation and migration of HUVECs were inhibited at levels as low as 5 nM. These chemical and biological properties demonstrated by the PTX-RUB nanoparticles may improve oral bioavailability and enable further pharmacokinetic, toxicologic, and efficacy investigations. PMID:25243454

  1. The inhibitory action of taxol on granulosa cell steroidogenesis is reversible.

    PubMed

    Chen, T T; Massey, P J; Caudle, M R

    1994-05-01

    Taxol is a novel anticancer agent extracted from the bark of Pacific yew trees. The drug has been approved by the FDA for the treatment of advanced ovarian cancer and is in clinical trials for other malignancies, including breast cancer. The goals of this study were to determine whether taxol adversely and irreversibly affects ovarian granulosa cell steroidogenesis. Cultured porcine granulosa cells were treated with taxol (0.12-12 microM) or vehicle (0.01-1% ethanol) in the absence or presence of 10(-9) M hCG in a time- and dose-response study. Morphological changes were recorded every 2 h, and media were collected for the measurement of progesterone (P4) and 17 beta-estradiol. Taxol suppressed both basal P4 and 17 beta-estradiol production and hCG-stimulated P4 production in a time- and dose-dependent manner and drastically changed cell shape by causing disorganization of microtubule bundles and other subcellular organelles. hCG partially reversed the steroid inhibition induced by taxol. These changes are not attributed to ethanol used as the vehicle, because ethanol at higher concentrations than that present in taxol did not suppress P4 production. When taxol was removed from the culture, P4 production returned to control levels. The results of this study show that taxol causes a significant, but reversible, inhibition of granulosa cell steroidogenesis. This inhibitory effect can be partially overcome by co-treatment with hCG. PMID:7908872

  2. Effects of genetic, epigenetic, and environmental factors on taxol content in Taxus brevifolia and related species.

    PubMed

    Wheeler, N C; Jech, K; Masters, S; Brobst, S W; Alvarado, A B; Hoover, A J; Snader, K M

    1992-04-01

    The demand for taxol, a promising cancer chemotherapeutic agent, far exceeds supply. Presently, taxol is derived from the bark of the Pacific yew, Taxus brevifolia, a small, slow-growing evergreen tree native to the northwestern United States. Knowledge of the distribution and magnitude of genetic and non-genetic sources of variation in taxol content in the genus Taxus is necessary if supply issues are to be met through plant harvesting. Analytical determinations of taxol, cephalomannine, and baccatin III in more than 200 trees representing several populations of T. brevifolia and other yew taxa indicate that (1) significant variation in taxane content exists among and within populations and species, (2) taxol levels exceeding those reported for T. brevifolia bark were found in shoots of individual trees from most taxa studied, and (3) the season in which samples are collected and handling procedures can influence taxane content. PMID:1355111

  3. Reactive oxygen species (ROS) is not a promotor of taxol-induced cytoplasmic vacuolization

    NASA Astrophysics Data System (ADS)

    Sun, Qingrui; Chen, Tongsheng

    2009-02-01

    we have previously reported that taxol, a potent anticancer agent, induces caspase-independent cell death and cytoplasmic vacuolization in human lung adenocarcinoma (ASTC-a-1) cells. However, the mechanisms of taxol-induced cytoplasmic vacuolization are poorly understood. Reactive oxygen species (ROS) has been reported to be involved in the taxol-induced cell death. Here, we employed confocal fluorescence microscopy imaging to explore the role of ROS in taxol-induced cytoplasmic vacuolization. We found that ROS inhibition by addition of N-acetycysteine (NAC), a total ROS scavenger, did not suppress these vacuolization but instead increased vacuolization. Take together, our results showed that ROS is not a promotor of the taxol-induced cytoplasmic vacuolization.

  4. Paclitaxel-loaded poly(N-vinylpyrrolidone)-b-poly(epsilon-caprolactone) nanoparticles: preparation and antitumor activity in vivo.

    PubMed

    Zhu, Zhenshu; Li, Yuan; Li, Xiaolin; Li, Rutian; Jia, Zhijun; Liu, Baorui; Guo, Wanhua; Wu, Wei; Jiang, Xiqun

    2010-03-19

    Paclitaxel (PTX)-loaded poly(N-vinylpyrrolidone)-b-poly(epsilon-caprolactone) (PVP-b-PCL) nanoparticles with high drug payload were successfully prepared by a modified nano-precipitation method and characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), dynamic light scattering (DLS) and zeta potential. The satisfactory drug loading content (>25%) and high encapsulation efficiency (>85%) were achieved. The in vivo real-time biodistribution of PTX-loaded nanoparticles was investigated using near-infrared fluorescence (NIRF) imaging. The antitumor effect of PTX-loaded nanoparticles was evaluated, both, in vitro on three different cancer cell lines and in vivo on hepatic H22 tumor bearing mice model via intravenous administration (i.v.). It is found that PTX-loaded nanoparticles exhibit significant superior in vivo antitumor effect than the commercially available Taxol formulation by combining the tumor volumes and survival rates measurement, intravital positron emission tomography and computed tomography (PET/CT) imaging. PMID:19896997

  5. Molecular and biomolecular-based nanomaterials: Tubulin and taxol as molecular constituents

    NASA Astrophysics Data System (ADS)

    Castro Carmona, Javier Servando

    The new field of protein-based nano-technology takes advantage of the complex interactions between proteins to form unique structures with properties that cannot be achieved with traditional components. Microtubules (MTs), self assembled proteinaceous hollow filaments, offer promise in the development of MT-based nano-systems. The compelling need for the controlled assembly of 3D MT arrays is the fundamental motivation for the first part of this research. We report on the morphology of MTs grown in a crowded environment in the form of high viscosity fluids containing agarose and a novel process that enables the assembly of MTs supported by gel-based 3D scaffolds. Our research on MTs and their interaction with other molecules lead us to discover extraordinary spherulitic structures that changed the course of the project. The novel subject situate us into a complicated dilemma that question the nature of MT asters reported in experiments carried out in cells. The second part of this research is focused in the crystallization of Taxol, a MT stabilizing molecule used as anti-cancer drug. It was confirmed via fluorescent and differential interference contrast microscopy that Taxol crystals can be decorated with fluorescent proteins and fluorochromes without perturbing their morphology. We used theoretical calculations to further investigate Taxol-fluorescent agent interactions. Furthermore, the crystallization of Taxol was studied in pure water, aqueous solutions containing tubulin proteins and tubulin-containing agarose gels. We demonstrated that tubulin is able to heterogeneously nucleate Taxol spherulites. To explain the formation of tubulin-Taxol nuclei a new, secondary Taxol-binding site within the tubulin heterodimer is suggested. Results presented in this work are important for in vivo and in vitro microtubule studies due to the possibility of mistaking these Taxol spherulites for microtubule asters. Thus, we are confirming the need for careful interpretation of fluorescence microscopy observations of MT structures when large concentrations of Taxol are used as stabilizing agent in cells.

  6. In vitro cell cultures obtained from different explants of Corylus avellana produce Taxol and taxanes

    PubMed Central

    Bestoso, Federica; Ottaggio, Laura; Armirotti, Andrea; Balbi, Alessandro; Damonte, Gianluca; Degan, Paolo; Mazzei, Mauro; Cavalli, Francesca; Ledda, Bernardetta; Miele, Mariangela

    2006-01-01

    Background Taxol is an effective antineoplastic agent, originally extracted from the bark of Taxus brevifolia with a low yield. Many attempts have been made to produce Taxol by chemical synthesis, semi-synthesis and plant tissue cultures. However, to date, the availability of this compound is not sufficient to satisfy the commercial requirements. The aim of the present work was to produce suspension cell cultures from plants not belonging to Taxus genus and to verify whether they produced Taxol and taxanes. For this purpose different explants of hazel (Corylus avellana species) were used to optimize the protocol for inducing in vitro callus, an undifferentiated tissue from which suspension cell cultures were established. Results Calli were successfully induced from stems, leaves and seeds grown in various hormone concentrations and combinations. The most suitable callus to establish suspension cell cultures was obtained from seeds. Media recovered from suspension cell cultures contained taxanes, and showed antiproliferative activity on human tumour cells. Taxol, 10-deacetyltaxol and 10-deacetylbaccatin III were the main taxanes identified. The level of Taxol recovered from the media of hazel cultures was similar to that found in yew cultures. Moreover, the production of taxanes in hazel cell cultures increased when elicitors were used. Conclusion Here we show that hazel cell cultures produce Taxol and taxanes under controlled conditions. This result suggests that hazel possesses the enzymes for Taxol production, which until now was considered to be a pathway particular to Taxus genus. The main benefit of producing taxanes through hazel cell cultures is that hazel is widely available, grows at a much faster rate in vivo, and is easier to cultivate in vitro than yew. In addition, the production of callus directly from hazel seeds shortens the culture time and minimizes the probability of contamination. Therefore, hazel could become a commercial source of Taxol and taxanes, both to be used as new therapeutic agents or as new precursors for Taxol semi-synthesis. PMID:17150090

  7. Biological evaluation of PEG modified nanosuspensions based on human serum albumin for tumor targeted delivery of paclitaxel.

    PubMed

    Yin, Tingjie; Cai, Han; Liu, Jiyong; Cui, Bei; Wang, Lei; Yin, Lifang; Zhou, Jianping; Huo, Meirong

    2016-02-15

    Since its approval by the FDA, Abraxane™ has been established as a clinical standard of paclitaxel (PTX)-based therapy against a variety of cancers. Despite success, Abraxane™ is still limited by suboptimal biodistribution, unfavorable pharmacokinetics and chronic toxicities from chloroform used during preparation. Accordingly, a PTX-loaded nanosuspension based on human serum albumin (HSA) with PEG modifiers (PTX-PEG-HSA) has been developed to optimize the in-vivo biodistribution, pharmacokinetics and safety of PTX over traditional PTX-HSA nanosuspensions prepared using the accepted method for Abraxane™. Results of in-vivo pharmacokinetic (PK) studies indicated PTX-PEG-HSA achieved prolonged blood circulation, illustrated by an 8.8-fold and 4.8-fold increase in area-under-the-curve (AUC) of PTX over Taxol® and PTX-HSA, while the mean residence time (MRT) of PTX in PTX-PEG-HSA was increased by 3.2-fold and 1.5-fold, respectively. HSA mediated active targeting further suppressed non-specific distribution of PTX to normal tissues, which permitted enhanced antitumor efficacy in S180 mice over Taxol® and PTX-HSA. Safety of intravenously administered PTX-PEG-HSA was confirmed through lower hemolytic activity, a 2.2-fold and 1.2-fold increase in LD50 (113.4mg/kg) over Taxol® and PTX-HSA alongside the absence of local venous irritation. Studies herein suggest the therapeutic and clinical applicability of PTX-PEG-HSA for tumor specific therapy. PMID:26699227

  8. Paclitaxel alters sensory nerve biomechanical properties.

    PubMed

    Bober, Brian G; Shah, Sameer B

    2015-10-15

    Paclitaxel is an effective chemotherapeutic that, despite its common use, frequently causes debilitating peripheral sensory neuropathy. Paclitaxel binds to and stabilizes microtubules, and through unknown mechanisms, causes abnormal microtubule aggregation. Given that microtubules contribute to the mechanical properties of cells, we tested the hypothesis that paclitaxel treatment would alter the stiffness of sensory nerves. Rat sural nerves were excised and soaked in Ringer's solution with or without paclitaxel. Nerves were secured between a force transducer and actuator, and linearly strained. Stress-strain curves were generated, from which elastic moduli were calculated. Paclitaxel treated nerves exhibited significantly higher moduli in both linear and transition regions of the curve. A composite-tissue model was then generated to estimate the stiffness increase in the cellular fraction of the nerve following paclitaxel treatment. This model was supported experimentally by data on mechanical properties of sural nerves stripped of their epineurium, and area fractions of the cellular and connective tissue components of the rat sural nerve, calculated from immunohistochemical images. Model results revealed that the cellular components of the nerve must stiffen 12x to 115x, depending on the initial axonal modulus assumed, in order to achieve the observed tissue level mechanical changes. Consistent with such an increase, electron microscopy showed increased microtubule aggregation and cytoskeletal packing, suggestive of a more cross-linked cytoskeleton. Overall, our data suggests that paclitaxel treatment induces increased microtubule bundling in axons, which leads to alterations in tissue-level mechanical properties. PMID:26321364

  9. Folate-modified lipid–polymer hybrid nanoparticles for targeted paclitaxel delivery

    PubMed Central

    Zhang, Linhua; Zhu, Dunwan; Dong, Xia; Sun, Hongfan; Song, Cunxian; Wang, Chun; Kong, Deling

    2015-01-01

    The purpose of this study was to develop a novel lipid–polymer hybrid drug carrier comprised of folate (FA) modified lipid-shell and polymer-core nanoparticles (FLPNPs) for sustained, controlled, and targeted delivery of paclitaxel (PTX). The core-shell NPs consist of 1) a poly(ε-caprolactone) hydrophobic core based on self-assembly of poly(ε-caprolactone)–poly(ethylene glycol)–poly(ε-caprolactone) (PCL-PEG-PCL) amphiphilic copolymers, 2) a lipid monolayer formed with 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy (polyethylene glycol)-2000] (DSPE-PEG2000), 3) a targeting ligand (FA) on the surface, and were prepared using a thin-film hydration and ultrasonic dispersion method. Transmission electron microscopy and dynamic light scattering analysis confirmed the coating of the lipid monolayer on the hydrophobic polymer core. Physicochemical characterizations of PTX-loaded FLPNPs, such as particle size and size distribution, zeta potential, morphology, drug loading content, encapsulation efficiency, and in vitro drug release, were also evaluated. Fluorescent microscopy proved the internalization efficiency and targeting ability of the folate conjugated on the lipid monolayer for the EMT6 cancer cells which overexpress folate receptor. In vitro cytotoxicity assay demonstrated that the cytotoxic effect of PTX-loaded FLPNPs was lower than that of Taxol®, but higher than that of PTX-loaded LPNPs (without folate conjugation). In EMT6 breast tumor model, intratumoral administration of PTX-loaded FLPNPs showed similar antitumor efficacy but low toxicity compared to Taxol®. More importantly, PTX-loaded FLPNPs showed greater tumor growth inhibition (65.78%) than the nontargeted PTX-loaded LPNPs (48.38%) (P<0.05). These findings indicated that the PTX loaded-FLPNPs with mixed lipid monolayer shell and biodegradable polymer core would be a promising nanosized drug formulation for tumor-targeted therapy. PMID:25844039

  10. Folate-modified lipid-polymer hybrid nanoparticles for targeted paclitaxel delivery.

    PubMed

    Zhang, Linhua; Zhu, Dunwan; Dong, Xia; Sun, Hongfan; Song, Cunxian; Wang, Chun; Kong, Deling

    2015-01-01

    The purpose of this study was to develop a novel lipid-polymer hybrid drug carrier comprised of folate (FA) modified lipid-shell and polymer-core nanoparticles (FLPNPs) for sustained, controlled, and targeted delivery of paclitaxel (PTX). The core-shell NPs consist of 1) a poly(ε-caprolactone) hydrophobic core based on self-assembly of poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCL-PEG-PCL) amphiphilic copolymers, 2) a lipid monolayer formed with 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy (polyethylene glycol)-2000] (DSPE-PEG2000), 3) a targeting ligand (FA) on the surface, and were prepared using a thin-film hydration and ultrasonic dispersion method. Transmission electron microscopy and dynamic light scattering analysis confirmed the coating of the lipid monolayer on the hydrophobic polymer core. Physicochemical characterizations of PTX-loaded FLPNPs, such as particle size and size distribution, zeta potential, morphology, drug loading content, encapsulation efficiency, and in vitro drug release, were also evaluated. Fluorescent microscopy proved the internalization efficiency and targeting ability of the folate conjugated on the lipid monolayer for the EMT6 cancer cells which overexpress folate receptor. In vitro cytotoxicity assay demonstrated that the cytotoxic effect of PTX-loaded FLPNPs was lower than that of Taxol(®), but higher than that of PTX-loaded LPNPs (without folate conjugation). In EMT6 breast tumor model, intratumoral administration of PTX-loaded FLPNPs showed similar antitumor efficacy but low toxicity compared to Taxol(®). More importantly, PTX-loaded FLPNPs showed greater tumor growth inhibition (65.78%) than the nontargeted PTX-loaded LPNPs (48.38%) (P<0.05). These findings indicated that the PTX loaded-FLPNPs with mixed lipid monolayer shell and biodegradable polymer core would be a promising nanosized drug formulation for tumor-targeted therapy. PMID:25844039

  11. Paclitaxel Albumin-stabilized Nanoparticle Formulation

    Cancer.gov

    This page contains brief information about paclitaxel albumin-stabilized nanoparticle formulation and a collection of links to more information about the use of this drug, research results, and ongoing clinical trials.

  12. Preparation of a paclitaxel-loaded cationic nanoemulsome and its biodistribution via direct intratumoral injection.

    PubMed

    Xu, Yurui; Asghar, Sajid; Li, Hongying; Chen, Minglei; Su, Zhigui; Xu, Yangfan; Ping, Qineng; Xiao, Yanyu

    2016-06-01

    In this study, a nano-preparation based on nanoemulsome (NES) modified with cetyltrimethylammonium bromide (CTAB) loading paclitaxel (PTX) was designed, and its biodistribution were explored after intratumoral (i.t.) administration on Heps tumor-bearing mice. The PTX-loaded nanoemulsome (PTX-NES) was prepared by using a solvent evaporation method and CTAB, chosen as a cationic material, was absorbed onto the surface of the NES via electrostatic interaction to yield paclitaxel-loaded cationic nanoemulsome (PTX-CTAB-NES). The MTT results exhibited that PTX-CTAB-NES (IC50: 0.50±0.035μg/mL in MCF-7 cells and 0.13±0.048μg/mL in SMMC-7721 cells) had the strongest cytotoxicity compared to Taxol (IC50: 0.88±0.054μg/mL in MCF-7 and 0.15±0.011μg/mL in SMMC-7721) and PTX-NES (IC50: 1.93±0.062μg/mL in MCF-7 and 0.32±0.027μg/mL in SMMC-7721). Body distribution of PTX revealed that the percent of PTX retained in the tumor after i.t. administration of PTX-CTAB-NES (approximately 92.99% at 0.167h and 15.35% at 48h) was higher when compared to that after i.t. injection of Taxol (approximately 58.94% at 0.167h and 0.83% at 48h) or PTX-NES (approximately 83.63% at 0.167h and 6.52% at 48h). Moreover, less PTX accumulated in liver, spleen, kidney, lung and heart after i.t. administration of PTX-CTAB-NES when compared with that after i.v. administration of PTX-CTAB-NES. In conclusion, PTX-CTAB-NES was a prospective in-situ delivery system for the therapy of tumor. PMID:26938323

  13. Paclitaxel improves outcome from traumatic brain injury

    PubMed Central

    Cross, Donna J.; Garwin, Gregory G.; Cline, Marcella M.; Richards, Todd L.; Yarnykh, Vasily; Mourad, Pierre D.; Ho, Rodney J.Y.; Minoshima, Satoshi

    2016-01-01

    Pharmacologic interventions for traumatic brain injury (TBI) hold promise to improve outcome. The purpose of this study was to determine if the microtubule stabilizing therapeutic paclitaxel used for more than 20 years in chemotherapy would improve outcome after TBI. We assessed neurological outcome in mice that received direct application of paclitaxel to brain injury from controlled cortical impact (CCI). Magnetic resonance imaging was used to assess injury-related morphological changes. Catwalk Gait analysis showed significant improvement in the paclitaxel group on a variety of parameters compared to the saline group. MRI analysis revealed that paclitaxel treatment resulted in significantly reduced edema volume at site-of-injury (11.92 ± 3.0 and 8.86 ± 2.2 mm3 for saline vs. paclitaxel respectively, as determined by T2-weighted analysis; p ≤ 0.05), and significantly increased myelin tissue preservation (9.45 ± 0.4 vs. 8.95 ± 0.3, p ≤ 0.05). Our findings indicate that paclitaxel treatment resulted in improvement of neurological outcome and MR imaging biomarkers of injury. These results could have a significant impact on therapeutic developments to treat traumatic brain injury. PMID:26086366

  14. Enhancement of esculetin on Taxol-induced apoptosis in human hepatoma HepG2 cells

    SciTech Connect

    Kuo, H.-C.; Lee, H.-J.; Hu, C.-C.; Shun, H.-I; Tseng, T.-H. . E-mail: tht@csmu.edu.tw

    2006-01-15

    The potential use of low dose chemotherapy has been appealing since lower dosages are more attainable during cancer therapy and cause less toxicity in patients. Combination therapy of Taxol, a promising frontline chemotherapy agent, with natural anti-tumor agents that are considerably less toxic with a capability of activating additional apoptotic signals or inhibiting survival signals may provide a rational molecular basis for novel chemotherapeutic strategies. Esculetin, a well-known lipoxygenase inhibitor, showed an inhibitory effect on the cell cycle progression of HL-60 cells in our previous study. In this report, the effects of a concomitant administration of esculetin and Taxol were investigated in human hepatoma HepG2 cells. Firstly, esculetin alone could exert an antiproliferation effect together with an inhibitory effect on the activation of ERKs and p38 MAPK. As compared to the treatment with Taxol only, a co-administration with esculetin and Taxol could result in a further enhancement of apoptosis as revealed by DNA fragmentation assay and Annexin-V-based assay. Meanwhile, immunoblotting analysis also showed that the co-administration of esculetin and Taxol could increase the expression of Bax and the cytosolic release of cytochrome C and enhance the expression of Fas and Fas ligand while the activation of caspase-8 and caspase-3 was also increased. Finally, the ERK cascade was proven to be involved in the enhancement of esculetin on the Taxol-induced apoptosis.

  15. Fate of paclitaxel lipid nanocapsules in intestinal mucus in view of their oral delivery

    PubMed Central

    Groo, Anne-Claire; Saulnier, Patrick; Gimel, Jean-Christophe; Gravier, Julien; Ailhas, Caroline; Benoit, Jean-Pierre; Lagarce, Frederic

    2013-01-01

    The bioavailability of paclitaxel (Ptx) has previously been improved via its encapsulation in lipid nanocapsules (LNCs). In this work, the interactions between LNCs and intestinal mucus are studied because they are viewed as an important barrier to successful oral delivery. The rheological properties of different batches of pig intestinal mucus were studied under different conditions (the effect of hydration and the presence of LNCs). Fluorescence resonance energy transfer (FRET) was used to study the stability of LNCs in mucus at 37°C for at least 3 hours. Diffusion through 223, 446, and 893 μm mucus layers of 8.4, 16.8, and 42 μg/mL Ptx formulated as Taxol® (Bristol-Myers Squibb, Rueil-Malmaison, France) or encapsulated in LNCs (Ptx-LNCs) were investigated. The effect of the size of the LNCs on their diffusion was also investigated (range, 25–110 nm in diameter). Mucus behaves as a non-Newtonian gel with rheofluidifying properties and a flow threshold. The viscous (G″) and elastic (G′) moduli and flow threshold of the two mucus batches varied with water content, but G′ remained below G″. LNCs had no effect on mucus viscosity and flow threshold. The FRET efficiency remained at 78% after 3 hours. Because the destruction of the LNCs would lead to a FRET efficiency below 25%, these results suggest only a slight modification of LNCs after their contact with mucus. The diffusion of Taxol® and Ptx-LNCs in mucus decreases if the mucus layer is thicker. Interestingly, the apparent permeability across mucus is higher for Ptx-LNCs than for Taxol® for drug concentrations of 16.8 and 42 μg/mL Ptx (P<0.05). The diffusion of Ptx-LNCs through mucus is not size-dependent. This study shows that LNCs are stable in mucus, do not change mucus rheological properties, and improve Ptx diffusion at low concentrations, thus making these systems good candidates for Ptx oral delivery. The study of the physicochemical interaction between the LNC surface and its diffusion in mucus is now envisioned. PMID:24235827

  16. Metabolism of taxol by human and rat liver in vitro: a screen for drug interactions and interspecies differences.

    PubMed

    Jamis-Dow, C A; Klecker, R W; Katki, A G; Collins, J M

    1995-01-01

    Human liver slices, human liver microsomes, and rat liver microsomes were used to investigate the metabolism of 3H-taxol. The effects of drugs frequently coadministered with taxol and the effects of several cytochrome P450 system probes were studied. In all, 16 compounds were screened. After incubation with liver slices or with microsomal protein, 3H-taxol was converted into several radioactive species resolved by HPLC. There were qualitative and quantitative species differences in the metabolism of taxol. The pattern of metabolism was similar for both human-derived preparations, with 6 alpha-hydroxytaxol being the major metabolite peak. In drug interaction studies performed with human liver microsomes, cimetidine 80 microM, and diphenhydramine 200 microM, had little or no effect on 6 alpha-hydroxytaxol formation. Quinidine, ketoconazole, dexamethasone and Cremophor EL inhibited 6 alpha-hydroxytaxol formation with IC50 values of 36 microM, 37 microM, 16 microM and 1 microliter/ml, respectively, but these concentrations exceed the usual clinical range. Cremophor EL also inhibited microsomal metabolism of taxol, but at 2 microliters/ml it had little or no effect on 6 alpha-hydroxytaxol production by human liver slices. These results suggest that: (1) taxol is metabolized by the cytochrome P450 system; (2) taxol metabolism is different in humans than in rats; (3) taxol metabolism in humans is unlikely to be altered by cimetidine, dexamethasone, or diphenhydramine, drugs regularly coadministered with taxol; (4) taxol metabolism can be indirectly affected by Cremophor EL, the formulation vehicle; (5) taxol metabolism may be altered by concentrations of ketoconazole achievable in humans only at very high doses; and (6) taxol metabolism and drug interaction studies of clinical relevance can be performed in vitro with human liver microsomes and human liver slices, but not with rat liver preparations. PMID:7767945

  17. Nab-Paclitaxel Plus Gemcitabine for Metastatic Pancreatic Cancer

    Cancer.gov

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

  18. Comparison of Epothilone and Taxol Binding in Yeast Tubulin using Molecular Modeling

    PubMed Central

    Akbari, Vajihe; Moghim, Sharareh; Reza Mofid, Mohammad

    2011-01-01

    Microtubules are unique cytoskeletal structures that have structural subunits of ?? tubulin. Taxol is a typical microtubule stabilizing drug. The epothilones are other natural products with similar mechanism of action totaxol. Despite the highly conserved nature of ?-tubulin, some organism like Saccharomyces cerevesia (S.cerevesia) is resistance to taxol, but sensitive to epothilones. In order to find differences in sensitivity of yeast tubulin to these molecules, we investigated binding mode of the taxol and epothilone A to yeast tubulin using molecular modeling. The multiple sequence alignment of ?-tubulin of different species was performed using ClustalW2. Protein structure of yeast ?-tubulin was constructed with Swiss Model 8.05 by using 1TVK. Modeled tubulin was superimposed with PyMol on1JFF for comparison of three-dimensional structure of two proteins. Our results showed that one of the most interesting differences in binding mode of these molecules is residue 227. The His227 in bovine makes a hydrogen bond by means of its ?-nitrogen with epothilone A and by means of its ?-nitrogen with taxol. The Asn227 of yeast can play role of the ?-nitrogen of imidazole ring of H227, but not of ?-nitrogen of it. So yeast tubulin in contrast to taxol can interact with epothilone A. Due to conservation of essential residues for binding (T274, R282 and Q292), epothilone A in comparison with taxol can tolerate the interchange in the binding pocket (R276I). Our findings may be of a great aid in the rational design of antitumor agents that bind to the taxol binding region of tubulin. PMID:23407671

  19. Cancer chemotherapy, biodiversity, public and private property: the case of the anti-cancer drug taxol.

    PubMed

    Walsh, V; Goodman, J

    1999-11-01

    The drug taxol has been hailed by many in the cancer community as a major breakthrough in the treatment of cancer. It has already been approved in use against ovarian and advanced breast cancer in many countries worldwide. Taxol has also promoted profound debates in the policy arena not, as one might expect, because of the characteristics or purposes of the drug itself, but because of other far-reaching effects. Taxol is a complex compound found in the bark of the Pacific yew tree, primarily in Oregon and Washington in the USA. The bark was first collected in 1962 and cytotoxicity demonstrated in 1964. Yet it was not until 1989 that the first results of clinical trials were reported. In the US taxol was then rushed through the Food and Drug Administration's regulatory procedures, approval being granted for use in refractory ovarian cancer in 1992. The controversies surrounding taxol surfaced in 1989 and grew substantially over the next few years. In this paper we examine two principal controversies concerning taxol, the first of which focused on apparent conflicts between the needs of environmental protection and those of cancer chemotherapy. Although the media portrayed this as a clash of interests between the environment and people with cancer, we argue that it was an attempt to increase lay participation in biomedical decision making and policy formulation. The second controversy was between health policy and the transfer of public scientific property to the corporate sector. The pharmaceutical company Bristol-Myers Squibb was given exclusive rights to provide taxol from Pacific yew trees under a Co-operative Research and Development Agreement signed in 1991. While this was seen to be in the US Government's (as well as the company's) interest, it provoked a public reaction questioning the terms and consequences of the transfer of publicly generated scientific knowledge to the private sector. PMID:10501642

  20. Insulin-Like Growth Factor 2 Silencing Restores Taxol Sensitivity in Drug Resistant Ovarian Cancer

    PubMed Central

    Brouwer-Visser, Jurriaan; Lee, Jiyeon; McCullagh, KellyAnne; Cossio, Maria J.; Wang, Yanhua; Huang, Gloria S.

    2014-01-01

    Drug resistance is an obstacle to the effective treatment of ovarian cancer. We and others have shown that the insulin-like growth factor (IGF) signaling pathway is a novel potential target to overcome drug resistance. The purpose of this study was to validate IGF2 as a potential therapeutic target in drug resistant ovarian cancer and to determine the efficacy of targeting IGF2 in vivo. An analysis of The Cancer Genome Atlas (TCGA) data in the serous ovarian cancer cohort showed that high IGF2 mRNA expression is significantly associated with shortened interval to disease progression and death, clinical indicators of drug resistance. In a genetically diverse panel of ovarian cancer cell lines, the IGF2 mRNA levels measured in cell lines resistant to various microtubule-stabilizing agents including Taxol were found to be significantly elevated compared to the drug sensitive cell lines. The effect of IGF2 knockdown on Taxol resistance was investigated in vitro and in vivo. Transient IGF2 knockdown significantly sensitized drug resistant cells to Taxol treatment. A Taxol-resistant ovarian cancer xenograft model, developed from HEY-T30 cells, exhibited extreme drug resistance, wherein the maximal tolerated dose of Taxol did not delay tumor growth in mice. Blocking the IGF1R (a transmembrane receptor that transmits signals from IGF1 and IGF2) using a monoclonal antibody did not alter the response to Taxol. However, stable IGF2 knockdown using short-hairpin RNA in HEY-T30 effectively restored Taxol sensitivity. These findings validate IGF2 as a potential therapeutic target in drug resistant ovarian cancer and show that directly targeting IGF2 may be a preferable strategy compared with targeting IGF1R alone. PMID:24932685

  1. Taxol inhibits the nuclear movements during fertilization and induces asters in unfertilized sea urchin eggs.

    PubMed

    Schatten, G; Schatten, H; Bestor, T H; Balczon, R

    1982-08-01

    Taxol blocks the migrations of the sperm and egg nuclei in fertilized eggs and induces asters in unfertilized eggs of the sea urchins Lytechinus variegatus and Arbacia punctulata. Video recordings of eggs inseminated in 10 microM taxol demonstrate that sperm incorporation and sperm tail motility are unaffected, that the sperm aster formed is unusually pronounced, and that the migration of the egg nucleus and pronuclear centration are inhibited. The huge monopolar aster persists for at least 6 h; cleavage attempts and nuclear cycles are observed. Colcemid (10 microM) disassembles both the large taxol-stabilized sperm aster in fertilized eggs and the numerous asters induced in unfertilized eggs. Antitubulin immunofluorescence microscopy demonstrates that in fertilized eggs all microtubules are within the prominent sperm aster. Within 15 min of treatment with 10 microM taxol, unfertilized eggs develop numerous (greater than 25) asters de novo. Transmission electron microscopy of unfertilized eggs reveals the presence of microtubule bundles that do not emanate from centrioles but rather from osmiophilic foci or, at times, the nuclear envelope. Taxol-treated eggs are not activated as judged by the lack of DNA synthesis, nuclear or chromosome cycles, and the cortical reaction. These results indicate that: (a) taxol prevents the normal cycles of microtubule assembly and disassembly observed during development; (b) microtubule disassembly is required for the nuclear movements during fertilization; (c) taxol induces microtubules in unfertilized eggs; and (d) nucleation centers other than centrioles and kinetochores exist within unfertilized eggs; these presumptive microtubule organizing centers appear idle in the presence of the sperm centrioles. PMID:6125518

  2. Taxol inhibits the nuclear movements during fertilization and induces asters in unfertilized sea urchin eggs

    PubMed Central

    1982-01-01

    Taxol blocks the migrations of the sperm and egg nuclei in fertilized eggs and induces asters in unfertilized eggs of the sea urchins Lytechinus variegatus and Arbacia punctulata. Video recordings of eggs inseminated in 10 microM taxol demonstrate that sperm incorporation and sperm tail motility are unaffected, that the sperm aster formed is unusually pronounced, and that the migration of the egg nucleus and pronuclear centration are inhibited. The huge monopolar aster persists for at least 6 h; cleavage attempts and nuclear cycles are observed. Colcemid (10 microM) disassembles both the large taxol-stabilized sperm aster in fertilized eggs and the numerous asters induced in unfertilized eggs. Antitubulin immunofluorescence microscopy demonstrates that in fertilized eggs all microtubules are within the prominent sperm aster. Within 15 min of treatment with 10 microM taxol, unfertilized eggs develop numerous (greater than 25) asters de novo. Transmission electron microscopy of unfertilized eggs reveals the presence of microtubule bundles that do not emanate from centrioles but rather from osmiophilic foci or, at times, the nuclear envelope. Taxol- treated eggs are not activated as judged by the lack of DNA synthesis, nuclear or chromosome cycles, and the cortical reaction. These results indicate that: (a) taxol prevents the normal cycles of microtubule assembly and disassembly observed during development; (b) microtubule disassembly is required for the nuclear movements during fertilization; (c) taxol induces microtubules in unfertilized eggs; and (d) nucleation centers other than centrioles and kinetochores exist within unfertilized eggs; these presumptive microtubule organizing centers appear idle in the presence of the sperm centrioles. PMID:6125518

  3. Taxol-induced mitotic block triggers rapid onset of a p53-independent apoptotic pathway.

    PubMed Central

    Woods, C. M.; Zhu, J.; McQueney, P. A.; Bollag, D.; Lazarides, E.

    1995-01-01

    BACKGROUND: At therapeutic concentrations, the antineoplastic agent taxol selectively perturbs mitotic spindle microtubules. Taxol has recently been shown to induce apoptosis, similar to the mechanism of cell death induced by other antineoplastic agents. However, taxol has shown efficacy against drug-refractory cancers, raising the possibility that this pharmacological agent may trigger an alternative apoptotic pathway. MATERIALS AND METHODS: The kinetics and IC50 of mitotic (M) block, aberrant mitosis, and cytotoxicity following taxol treatment were analyzed in human cell lines as well as normal mouse embryo fibroblasts (MEFs) and MEFs derived from p53-null mice. Apoptosis was followed by DNA gel electrophoresis and by in situ DNA end-labeling (TUNEL). RESULTS: Taxol induced two forms of cell cycle arrest: either directly in early M at prophase or, for those cells progressing through aberrant mitosis, arrest in G1 as multimininucleated cells. TUNEL labeling revealed that DNA nicking occurred within 30 min of the arrest in prophase. In contrast, G1-arrested, multimininucleated cells became TUNEL positive only after several days. In the subset of cells that became blocked directly in prophase, both wt p53-expressing and p53-null MEFs responded similarly to taxol, showing rapid onset of DNA nicking and apoptosis. However, p53-null MEFs progressing through aberrant mitosis failed to arrest in the subsequent G1 phase or to become TUNEL positive, and remained viable. CONCLUSIONS: Taxol induces two forms of cell cycle arrest, which in turn induce two independent apoptotic pathways. Arrest in prophase induces rapid onset of a p53-independent pathway, whereas G1-block and the resulting slow (3-5 days) apoptotic pathway are p53 dependent. Images FIG. 2 FIG. 3 FIG. 4 FIG. 5 FIG. 8 FIG. 9 FIG. 11 PMID:8529117

  4. Oral microemulsions of paclitaxel: in situ and pharmacokinetic studies.

    PubMed

    Nornoo, Adwoa O; Zheng, Haian; Lopes, Luciana B; Johnson-Restrepo, Boris; Kannan, Kurunthachalam; Reed, Rachel

    2009-02-01

    The overall goal of this study was to develop cremophor-free oral microemulsions of paclitaxel (PAC) to enhance its permeability and oral absorption. The mechanism of this enhancement, as well as characteristics of the microemulsions relevant to the increase in permeability and absorption of the low solubility, low permeability PAC was investigated. Phase diagrams were used to determine the macroscopic phase behavior of the microemulsions and to compare the efficiency of different surfactant-oil mixtures to incorporate water. The microemulsion region on the phase diagrams utilizing surfactant-myvacet oil combinations was in decreasing order: lecithin: butanol: myvacet oil (LBM, 48.5%)>centromix CPS: 1-butanol: myvacet oil (CPS, 45.15%)>capmul MCM: polysorbate 80: myvacet oil (CPM, 27.6%)>capryol 90: polysorbate 80: myvacet oil (CP-P80, 23.9%)>capmul: myvacet oil (CM, 20%). Oil-in-water (o/w) microemulsions had larger droplet sizes (687-1010 nm) than the water-in-oil (w/o) microemulsions (272-363 nm) when measured using a Zetasizer nano series particle size analyzer. Utilizing nuclear magnetic resonance spectroscopy (NMR), the self-diffusion coefficient (D) of PAC in CM, LBM and CPM containing 10% of deuterium oxide (D(2)O) was 2.24x10(-11), 1.97x10(-11) and 0.51x10(-11) m(2)/s, respectively. These values indicate the faster molecular mobility of PAC in the two w/o microemulsions (CM and LBM) than the o/w microemulsion--CPM. The in situ permeability of PAC through male CD-IGS rat intestine was 3- and 11-fold higher from LBM and CM, respectively, than that from the control clinical formulation, Taxol (CE, cremophor: ethanol) in a single pass perfusion study. PAC permeability was significantly increased in the presence of the pgp/CYP3A4 inhibitor cyclosporine A (CsA). This enhancement may be attributed to the pgp inhibitory effect of the surfactants, oil and/or the membrane perturbation effect of the surfactants. The oral disposition of PAC in CM, LBM and CPM compared to CE was studied in male CD-IGS rats after a single oral dose (20 mg/kg). The area-under-the-curve of PAC in CM was significantly larger than LBM, CPM and CE. Oral microemulsions of PAC were developed that increased both the permeability and AUC of PAC as compared to CE. PMID:18793723

  5. Effects of PEGylated paclitaxel nanocrystals on breast cancer and its lung metastasis

    NASA Astrophysics Data System (ADS)

    Zhang, Hua; Hu, Hongxiang; Zhang, Haoran; Dai, Wenbing; Wang, Xinglin; Wang, Xueqing; Zhang, Qiang

    2015-06-01

    As an attractive strategy developed rapidly in recent years, nanocrystals are used to deliver insoluble drugs. PEGylation may further prolong the circulation time of nanoparticles and improve the therapeutic outcome of drugs. In this study, paclitaxel (PTX) nanocrystals (PTX-NCs) and PEGylated PTX nanocrystals (PEG-PTX-NCs) were prepared using antisolvent precipitation augmented by probe sonication. The characteristics and antitumor efficacy of nanocrystals were investigated. The results indicated that the nanocrystals showed rod-like morphology, and the average particle size was 240 nm and 330 nm for PTX-NCs and PEG-PTX-NCs, respectively. The PEG molecules covered the surface of nanocrystals with an 11.54 nm fixed aqueous layer thickness (FALT), much higher than that of PTX-NCs (0.2 nm). PEG-PTX-NCs showed higher stability than PTX-NCs under both storage and physiological conditions. In breast cancer xenografted mice, PEG-PTX-NCs showed significantly better tumor inhibition compared to saline (p < 0.001) and PTX-NC groups (p < 0.05) after intravenous administration. In a model of lung tumor metastasis quantified by the luciferase activity, the PEG-PTX-NCs group showed higher anticancer efficacy not only than saline and PTX-NCs groups, but also than Taxol®, achieving an 82% reduction at the end of the experiment. These studies suggested the potential advantages of PEGylated PTX nanocrystals as alternative drug delivery systems for anticancer therapy.

  6. Biological and ultrastructural effects of the anti-microtubule agent taxol against Trypanosoma cruzi.

    PubMed

    Dantas, A P; Barbosa, H S; De Castro, S L

    2003-07-01

    Microtubules play fundamental roles in eukaryotic cells and have been investigated as target for drugs. Several studies showed the potential use of anti-microtubule agents against pathogenic protozoa. Taxol has been intensively studied in Leishmania spp. and microtubules have been considered as a promising antileishmanial drug target. It has been also shown that taxol interferes with the proliferation of Trypanosoma cruzi, leading to morphological alterations and interruption of nuclear division and cytokinesis. In the present work we show that T. cruzi bloodstream trypomastigotes were much more susceptible than epimastigotes, and in both forms taxol caused severe ultrastructural damage, especially associated to changes in the shape of the parasites. In trypomastigotes, different degrees of body contortion along the longitudinal axis and a marked dilatation of the flagellar pocket were detected. Treated epimastigotes presented a decrease in the electron density of the mitochondrial matrix, absence of mitochondrial cristae and an increase in the number of lipid droplets. Bizarre multi-flagellar epimastigotes were also detected, suggesting an interruption of the cytokinesis. Taxol caused no noticeable ultrastructural alterations on sub-pellicular and flagellar microtubules of both evolutive forms of T. cruzi. As already described in the literature, such structures in trypanosomatids are very resistant to microtubule disrupters when compared to those in mammalian cells. Taxol prevented the endocytosis of albumin-gold complexes by epimastigotes, and this result could be associated to the loss of the dynamic stability of the microtubules of the cytostome. PMID:14690177

  7. A3 adenosine receptor agonist prevents the development of paclitaxel-induced neuropathic pain by modulating spinal glial-restricted redox-dependent signaling pathways

    PubMed Central

    Janes, Kali; Esposito, Emanuela; Doyle, Timothy; Cuzzocrea, Salvatore; Tosh, Dillip K.; Jacobson, Kenneth A.; Salvemini, Daniela

    2015-01-01

    Chemotherapy-induced peripheral neuropathy (CIPN) accompanied by chronic neuropathic pain is the major dose-limiting toxicity of several anticancer agents including the taxane paclitaxel (Taxol®). A critical mechanism underlying paclitaxel-induced neuropathic pain is the increased production of peroxynitrite (PN) in spinal cord generated in response to activation of the superoxide-generating enzyme, NADPH oxidase. PN in turn contributes to the development of neuropathic pain by modulating several redox-dependent events in spinal cord. We recently reported that activation of the Gi/Gq-coupled A3 adenosine receptor (A3AR) with selective A3AR agonists (i.e., IB-MECA) blocked the development of chemotherapy induced-neuropathic pain evoked by distinct agents, including paclitaxel, without interfering with anticancer effects. The mechanism(s) of action underlying these beneficial effects has yet to be explored. We now demonstrate that IB-MECA attenuates the development of paclitaxel-induced neuropathic pain by inhibiting the activation of spinal NADPH oxidase and two downstream redox-dependent systems. The first relies on inhibition of the redox-sensitive transcription factor (NFκB) and mitogen activated protein kinases (ERK and p38) resulting in a decreased production of neuroexcitatory/pro-inflammatory cytokines (TNF-α, IL-1β) and increased formation of the neuroprotective/anti-inflammatory IL-10. The second involves inhibition of redox-mediated posttranslational tyrosine nitration and modification (inactivation) of glia-restricted proteins known to play key roles in regulating synaptic glutamate homeostasis: the glutamate transporter GLT-1 and glutamine synthetase. Our results unravel a mechanistic link into biomolecular signaling pathways employed by A3AR activation in neuropathic pain while providing the foundation to consider use of A3AR agonists as therapeutic agents in CIPN patients. PMID:25242567

  8. Initial experience with paclitaxel-coated stents.

    PubMed

    Grube, Eberhard; Büllesfeld, Lutz

    2002-12-01

    Local delivery of immunosuppressive or antiproliferative agents using a drug-eluting stent is a new technology that is supposed to inhibit in-stent restenosis, thus providing a biological and mechanical solution. This technique is a very promising. To date, several agents have been used, including paclitaxel, QP-2, rapamycin, actinomycin D, dexamethason, tacrolimus, and everolimus. Several studies, published recently or still ongoing, have evaluated these drugs as to their release kinetics, effective dosage, safety in clinical practice, and benefit. These studies include: SCORE (paclitaxel derivative), TAXUS I-VI, ELUTES, ASPECT, DELIVER (paclitaxel), RAVEL, SIRIUS (sirolimus), ACTION (actinomycin), EVIDENT, PRESENT (tacrolimus), EMPEROR (dexamethason), and FUTURE (everolimus). Paclitaxel was one of the first stent-based antiproliferative agents under clinical investigation that provided profound inhibition of neointimal thickening depending on delivery duration and drug dosage. The randomized, multicenter SCORE trail (Quanam stent, paclitaxel-coated) enrolled 266 patients at 17 sites. At 6-month's follow-up, a drop of 83% in stent restenosis using the drug-eluting stent could be achieved (6.4% drug-eluting stent vs 36.9% control group), which was attributable to a remarkable decrease in intimal proliferation. Unfortunately, due to frequent stent thrombosis and side-branch occlusions, the reported 30-day MACE rate was 10.2%. The randomized TAXUS-I safety trial (BSC, NIRx, paclitaxel-coated) also demonstrated beneficial reduction of restenotic lesions at 6-month's follow-up (0% vs 10%) but was associated with the absence of thrombotic events presumably due to less drug dosage. The ongoing TAXUS II-VI trials are addressing additional insight regarding the efficacy of the TAXUS paclitaxel-eluting stent. ASPECT and ELUTES evaluated paclitaxel-coated stents (i.e., Cook and Supra G), including subgroups with different drug dosages. With respect to stent restenosis and neointimal proliferation, both studies demonstrated a clear dose response. The RAVEL and the SIRIUS trials evaluated sirolimus-coated stents (i.e., Cordis, Johnson & Johnson, and Bx VELOCITY stents). Results confirmed the beneficial findings regarding reduction of renarrowing using a drug-eluting stent without any major adverse effects. Although parameters such as drug toxicity, optimal drug dosage, or delayed endothelial healing still need to be evaluated, today's clinical experience indicates that drug-coated stents are extremely beneficial in the interventional treatment of coronary lesions. PMID:12476650

  9. Overcoming drug-resistant lung cancer by paclitaxel loaded dual-functional liposomes with mitochondria targeting and pH-response.

    PubMed

    Jiang, Lei; Li, Li; He, Xiaodan; Yi, Qiangying; He, Bin; Cao, Jun; Pan, Weisan; Gu, Zhongwei

    2015-06-01

    Mitochondrion-orientated transportation of smart liposomes has been developed as a promising strategy to deliver anticancer drugs directly to tumor sites, and these have a tremendous potential for killing cancer cells, especially those with multidrug resistance (MDR). Herein we report a novel dual-functional liposome system possessing both extracellular pH response and mitochondrial targeting properties to enhance drug accumulation in mitochondria and trigger apoptosis of drug-resistant cancer cells. Briefly, peptide D[KLAKLAK]2 (KLA) was modified with 2, 3-dimethylmaleic anhydride (DMA) and combined with 1, 2-distearoyl-sn-glycero-3-phosphoethanolamine (DSPE) to yield a DSPE-KLA-DMA (DKD) lipid. This dual-functional DKD was then mixed with other commercially available lipids to fabricate liposomes. In vitro anticancer efficacy of this liposome system was evaluated in human lung cancer A549 cells and drug-resistant lung cancer A549/Taxol cells. At tumor extracellular pH (∼6.8), liposomes could reverse their surface charge (negative to positive), facilitating liposome internalization. After cellular uptake, KLA peptide directed delivery-enabled selective accumulation of these liposomes into mitochondria and favored release of their cargo paclitaxel (PTX) into desired sites. Specifically, enhanced apoptosis of MDR cancer cells through mitochondrial signaling pathways was evidenced by release of cytochrome c and increased activity of caspase-9 and -3. These dual-functional liposomes had the greatest efficacy for treating A549 cells and A549/Taxol cells in vitro, and in treating drug-resistant lung cancer A549/Taxol cells xenografted onto nude mice (tumor growth inhibition 86.7%). In conclusion, dual-functional liposomes provide a novel and versatile approach for overcoming MDR in cancer treatment. PMID:25818419

  10. An Italian cost-effectiveness analysis of paclitaxel albumin (nab-paclitaxel) versus conventional paclitaxel for metastatic breast cancer patients: the COSTANza study

    PubMed Central

    Lazzaro, Carlo; Bordonaro, Roberto; Cognetti, Francesco; Fabi, Alessandra; De Placido, Sabino; Arpino, Grazia; Marchetti, Paolo; Botticelli, Andrea; Pronzato, Paolo; Martelli, Elisa

    2013-01-01

    Purpose Paclitaxel albumin (nab-paclitaxel) is a nanoparticle albumin-bound paclitaxel formulation aimed at increasing therapeutic index in metastatic breast cancer. When compared to conventional paclitaxel, nab-paclitaxel has a reported longer time to progression, higher response, lower incidence of neutropenia, no need for premedication, shorter time of administration, and in pretreated metastatic breast cancer patients, extended overall survival. This study investigates the cost-effectiveness of nab-paclitaxel versus conventional paclitaxel for pretreated metastatic breast cancer patients in Italy. Materials and methods A Markov model with progression-free, progressed, and dead states was developed to estimate costs, outcomes, and quality adjusted life years over 5 years from the Italian National Health Service viewpoint. Patients were assumed to receive nab-paclitaxel 260 mg/m2 three times weekly or conventional paclitaxel 175 mg/m2 three times weekly. Data on health care resource consumption was collected from a convenience sample of five Italian centers. Resources were valued at Euro (€) 2011. Published utility weights were applied to health states to estimate the impact of response, disease progression, and adverse events on quality adjusted life years. Three sensitivity analyses tested the robustness of the base case incremental cost-effectiveness ratio (ICER). Results and conclusion Compared to conventional paclitaxel, nab-paclitaxel gains an extra 0.165 quality adjusted life years (0.265 life years saved) and incurs additional costs of €2506 per patient treated. This translates to an ICER of €15,189 (95% confidence interval: €11,891–€28,415). One-way sensitivity analysis underscores that ICER for nab-paclitaxel remains stable despite varying taxanes cost. Threshold analysis shows that ICER for nab-paclitaxel exceeds €40,000 only if cost per mg of conventional paclitaxel is set to zero. Probabilistic sensitivity analysis highlights that nab-paclitaxel has a 0.99 probability to be cost-effective for a threshold value of €40,000 and is the optimal alternative from a threshold value of €16,316 onwards. Based on these findings, nab-paclitaxel can be considered highly cost-effective when compared to the acceptability range for ICER proposed by the Italian Health Economics Association (€25,000–€40,000). PMID:23610525

  11. Postoperative dose-dense sequential versus concomitant administration of epirubicin and paclitaxel in patients with node-positive breast cancer: 5-year results of the Hellenic Cooperative Oncology Group HE 10/00 phase III Trial.

    PubMed

    Gogas, Helen; Dafni, Urania; Karina, Maria; Papadimitriou, Christos; Batistatou, Anna; Bobos, Mattheos; Kalofonos, Haralabos P; Eleftheraki, Anastasia G; Timotheadou, Eleni; Bafaloukos, Dimitrios; Christodoulou, Christos; Markopoulos, Christos; Briasoulis, Evangelos; Papakostas, Pavlos; Samantas, Epaminontas; Kosmidis, Paris; Stathopoulos, George P; Karanikiotis, Charisios; Pectasides, Dimitrios; Dimopoulos, Meletios A; Fountzilas, George

    2012-04-01

    To explore the impact of dose intensity (DI) in the adjuvant setting of breast cancer, a randomized phase III trial was conducted comparing postoperative dose-dense sequential chemotherapy with epirubicin, paclitaxel, and cyclophosphamide, methotrexate and fluorouracil (CMF)in high-risk breast cancer patients. From Oct 2000 to June 2005, 1,121 node-positive patients were randomized to dose-dense sequential epirubicin 110 mg/m(2) and paclitaxel (Taxol, Bristol Myers-Squibb, Princeton, NJ) 250 mg/m(2) (group A), or concurrent epirubicin 83 mg/m(2) and paclitaxel 187 mg/m(2) (group B), both followed by three cycles of "intensified" combination chemotherapy with CMF. By protocol design total cumulative dose and duration of treatment were identical in both groups. Dose intensity of epirubicin and paclitaxel was double in the dose-dense arm. Prophylactic treatment with granulocyte colony-stimulating factor was given with the dose-dense treatments. Disease-free survival (DFS) was the primary endpoint. At a median follow-up of 76 months, 253 patients (23%) had documented disease relapse (123 vs. 130 in groups A and B, respectively) and 208 deaths (101, group A and 107, group B) had been observed. The 5-year DFS rate of 74 and 74% and OS rate of 86 and 85% were observed for group A and group B, respectively. No differences were found in DFS or OS between the two treatment groups (P = 0.78 and P = 0.45 for DFS and OS, respectively). Safety analysis results showing that both regimens were well tolerated and safe have been previously published (Fountzilas et al. Ann Oncol 2008). No DFS or OS benefit from the dose-dense sequential epirubicin and paclitaxel was detected when compared to the concurrent administration of the same drugs. No additional safety issues were raised with long-term follow-up. PMID:22187126

  12. D-α-tocopherol polyethylene glycol succinate-based derivative nanoparticles as a novel carrier for paclitaxel delivery

    PubMed Central

    Wu, Yupei; Chu, Qian; Tan, Songwei; Zhuang, Xiangting; Bao, Yuling; Wu, Tingting; Zhang, Zhiping

    2015-01-01

    Paclitaxel (PTX) is one of the most effective antineoplastic drugs. Its current clinical administration Taxol® is formulated in Cremophor EL, which causes serious side effects. Nanoparticles (NP) with lower systemic toxicity and enhanced therapeutic efficiency may be an alternative formulation of the Cremophor EL-based vehicle for PTX delivery. In this study, novel amphipathic 4-arm-PEG-TPGS derivatives, the conjugation of D-α-tocopherol polyethylene glycol succinate (TPGS) and 4-arm-polyethylene glycol (4-arm-PEG) with different molecular weights, have been successfully synthesized and used as carriers for the delivery of PTX. These 4-arm-PEG-TPGS derivatives were able to self-assemble to form uniform NP with PTX encapsulation. Among them, 4-arm-PEG5K-TPGS NP exhibited the smallest particle size, highest drug-loading efficiency, negligible hemolysis rate, and high physiologic stability. Therefore, it was chosen for further in vitro and in vivo investigations. Facilitated by the effective uptake of the NP, the PTX-loaded 4-arm-PEG5K-TPGS NP showed greater cytotoxicity compared with free PTX against human ovarian cancer (A2780), non-small cell lung cancer (A549), and breast adenocarcinoma cancer (MCF-7) cells, as well as a higher apoptotic rate and a more significant cell cycle arrest effect at the G2/M phase in A2780 cells. More importantly, PTX-loaded 4-arm-PEG5K-TPGS NP resulted in a significantly improved tumor growth inhibitory effect in comparison to Taxol® in S180 sarcoma-bearing mice models. This study suggested that 4-arm-PEG5K-TPGS NP may have the potential as an anticancer drug delivery system. PMID:26316751

  13. Taxol shares the ability of bacterial lipopolysaccharide to induce tyrosine phosphorylation of microtubule-associated protein kinase.

    PubMed

    Ding, A; Sanchez, E; Nathan, C F

    1993-11-15

    Microtubule-associated proteins may mediate the activation of macrophages by bacterial LPS. Three lines of evidence support this hypothesis: a) Taxol, a microtubule-binding diterpene, mimics the ability of LPS to induce cytokines and down-regulate receptors for TNF-alpha. In recombinant inbred mouse strains differing at the Lps gene, responsiveness to these effects of Taxol co-segregates with responsiveness to LPS. b) In vitro, LPS binds specifically to MT and preferentially to beta-tubulin. c) LPS activates microtubule-associated protein-2 kinase (MAPK). The present studies bring together and extend these lines of evidence. a) Taxol, like LPS, rapidly induces tyrosine phosphorylation of MAPK in mouse macrophages, and triggers MAPK to phosphorylate an exogenous substrate. b) Tyrosine phosphorylation of MAPK is an extremely rapid cellular response both to taxol and LPS. c) Macrophages from C3H/HeJ mice, which carry a defective Lps gene, fail to activate MAPK in response to taxol or LPS, although they activate MAPK in response to insulin or IFN-gamma. These results suggest that tyrosine phosphorylation of MAPK is among the earliest known response of macrophages to LPS. Taxol mimics LPS with respect to immediate MAPK activation, later transcriptional events, and the genetic control of both sets of responses. LPS and taxol thus appear to share an early step in a functionally important signal transduction pathway that may involve MT. PMID:7901279

  14. Taxol inhibits neointimal smooth muscle cell accumulation after angioplasty in the rat.

    PubMed Central

    Sollott, S J; Cheng, L; Pauly, R R; Jenkins, G M; Monticone, R E; Kuzuya, M; Froehlich, J P; Crow, M T; Lakatta, E G; Rowinsky, E K

    1995-01-01

    Despite significant improvements in the primary success rate of the medical and surgical treatments for atherosclerotic disease, including angioplasty, bypass grafting, and endarterectomy, secondary failure due to late restenosis continues to occur in 30-50% of individuals. Restenosis and the later stages in atherosclerotic lesions are due to a complex series of fibroproliferative responses to vascular injury involving potent growth-regulatory molecules (such as platelet-derived growth factor and basic fibroblast growth factor) and resulting in vascular smooth muscle cell (VSMC) proliferation, migration, and neointimal accumulation. We show here, based on experiments with both taxol and deuterium oxide, that microtubules are necessary for VSMCs to undergo the multiple transformations contributing to the development of the neointimal fibroproliferative lesion. Taxol was found to interfere both with platelet-derived growth factor-stimulated VSMC migration and with VSMC migration and with VSMC proliferation, at nanomolar levels in vitro. In vivo, taxol prevented medial VSMC proliferation and the neointimal VSMC accumulation in the rat carotid artery after balloon dilatation and endothelial denudation injury. This effect occurred at plasma levels approximately two orders of magnitude lower than that used clinically to treat human malignancy (peak levels achieved in this model were approximately 50-60 nM). Taxol may therefore be of therapeutic value in preventing human restenosis with minimal toxicity. Images PMID:7706494

  15. Monoclonal Antibodies Attached to Carbon Nanotube Transistors for Paclitaxel Detection

    NASA Astrophysics Data System (ADS)

    Lee, Wonbae; Lau, Calvin; Richardson, Mark; Rajapakse, Arith; Weiss, Gregory; Collins, Philip; UCI, Molecular Biology; Biochemistry Collaboration; UCI, Departments of Physics; Astronomy Collaboration

    Paclitaxel is a naturally-occurring pharmaceutical used in numerous cancer treatments, despite its toxic side effects. Partial inhibition of this toxicity has been demonstrated using weakly interacting monoclonal antibodies (3C6 and 8A10), but accurate monitoring of antibody and paclitaxel concentrations remains challenging. Here, single-molecule studies of the kinetics of antibody-paclitaxel interactions have been performed using single-walled carbon nanotube field-effect transistors. The devices were sensitized with single antibody attachments to record the single-molecule binding dynamics of paclitaxel. This label-free technique recorded a range of dynamic interactions between the antibody and paclitaxel, and it provided sensitive paclitaxel detection for pM to nM concentrations. Measurements with two different antibodies suggest ways of extending this working range and uncovering the mechanistic differences among different antibodies.

  16. Experimental design towards an optimal lipid nanosystem: a new opportunity for paclitaxel-based therapeutics.

    PubMed

    Videira, Mafalda A; Arranja, Alexandra G; Gouveia, Luís F

    2013-05-13

    Lipid based nanoparticles represent a class of nanocarriers that have caused great expectation, particularly due to their suitability to incorporate BCS class II and IV drugs. The use of solid lipid nanoparticles (SLNs) as a nanocarrier for antineoplastic agents has been underexplored when compared to the encapsulation of the same agents in polymeric particles. The preparation and efficacy assessment of a SLN platform as drug delivery carrier for anticancer agents, herein proposed as a strategy to find innovative formulations, could dramatically improve the outcome of cancer therapy. Considering these lipid nanoparticles, despite the great amount of insights described in the literature, it seems that improving their manufacturability could be the missing step to convert this system into a drug product. A way to circumvent that problem would be to select a preparation method that could take advantage of the pharmaceutical industry installed capabilities, thus speeding-up the scale-up translational steps while maintaining both regulatory compliance and flexibility. The High Pressure Homogenization (HPH) has proved to be a reliable process for SLN preparation. However, the use of the high-shear mixer, a well established process to manufacture coarse dispersions at industrial scale, has still not been fully explored to prepare SLN. In this study, we explore the possibility of using the hot emulsification/solidification method to prepare SLN's that complies with the current pharmaceutical quality requirements. Thus, a high-shear based process that consistently accomplishes performance requirements was optimized in order to standardize the nanocarrier production following the identification of some process and formulation critical parameters. A hydrophobic drug, Paclitaxel (Ptx) was successfully incorporated using the proposed developed method. The particles physicochemical characteristics changes caused by the drug entrapment as well as the particles stability were also evaluated. In addition the ability of SLN to travel across biological barriers due to its matrix lipid nature was explored upon comparing the efficacy of the drug loaded SLN with the conventional marketed drug product (Taxol®). The cellular uptake studies showed that the developed Ptx loaded SLN were in fact internalized and demonstrated higher efficacy in the cancer cells death process than Taxol. The experimental data demonstrated that the hot homogenization technique using a high-shear mechanical homogenizer allows the preparation of suitable size (around 150 nm) SLN. Overall, the results obtained can be particularly impactful in the forthcoming SLN research. PMID:23528739

  17. Isolation of a novel microorganism, pestalotia heterocornis, producing paclitaxel

    PubMed

    Noh; Yang; Kim; Yoon; Kang; Han; Shim; Park

    1999-09-01

    Pestalotia heterocornis was isolated from soil collected in yew forest and was shown to produce paclitaxel in semisynthetic liquid media. The presence of paclitaxel in the fungal extract was confirmed by FAB mass spectrometry and NMR spectroscopy. The maximum yield of paclitaxel was 31 &mgr;g per liter. Optimal paclitaxel production occurred after 5-7 days in a 20-liter scale fermentation at 23 degrees C. These results indicate that P. heterocornis is an excellent candidate for consideration in fermentation technology. Copyright 1999 John Wiley & Sons, Inc. PMID:10404243

  18. Prolonged remission of recurrent cervical carcinoma following paclitaxel and carboplatin chemotherapy with paclitaxel maintenance chemotherapy.

    PubMed

    Micha, John P; Sassoon, Aaron F; Wong, Humberto; Goldstein, Bram H

    2015-08-01

    Cervical cancer recurs in ~30% of cases, for which a favorable prognosis is often unattainable. We describe a cervical cancer patient who developed metastatic disease ~5 years after her initial diagnosis. She was subsequently treated with six cycles of paclitaxel (175 mg/m) and carboplatin area under the curve (AUC) 5 chemotherapy every 21 days, and paclitaxel (135 mg/m) maintenance therapy every 21 days; the patient has remained in clinical remission after more than 5 years of follow-up. Chemotherapy has not historically been effective in managing recurrent, persistent, or metastatic cervical cancer. However, our case study involving paclitaxel and carboplatin chemotherapy with maintenance chemotherapy represents one of the longest documented remission rates in association with the management of recurrent cervical cancer. PMID:25933247

  19. Complete Regression of Xenograft Tumors upon Targeted Delivery of Paclitaxel via Π-Π Stacking Stabilized Polymeric Micelles

    PubMed Central

    Shi, Yang; van der Meel, Roy; Theek, Benjamin; Blenke, Erik Oude; Pieters, Ebel H.E.; Fens, Marcel H.A.M.; Ehling, Josef; Schiffelers, Raymond M.; Storm, Gert; van Nostrum, Cornelus F.; Lammers, Twan; Hennink, Wim E.

    2015-01-01

    Treatment of cancer patients with taxane-based chemotherapeutics, such as paclitaxel (PTX), is complicated by their narrow therapeutic index. Polymeric micelles are attractive nanocarriers for tumor-targeted delivery of PTX, as they can be tailored to encapsulate large amounts of hydrophobic drugs and achieve prolonged circulation kinetics. As a result, PTX deposition in tumors is increased while drug exposure to healthy tissues is reduced. However, many PTX-loaded micelle formulations suffer from low stability and fast drug release in the circulation, limiting their suitability for systemic drug targeting. To overcome these limitations, we have developed paclitaxel (PTX)-loaded micelles which are stable without chemical crosslinking and covalent drug attachment. These micelles are characterized by excellent loading capacity and strong drug retention, attributed to π-π stacking interaction between PTX and the aromatic groups of the polymer chains in the micellar core. The micelles are based on methoxy poly(ethylene glycol)-b-(N-(2-benzoyloxypropyl) methacrylamide) (mPEG-b-p(HPMAm-Bz)) block copolymers, which improved the pharmacokinetics and the biodistribution of PTX, and substantially increased PTX tumor accumulation (by more than 2000%; as compared to Taxol® or control micellar formulations). Improved biodistribution and tumor accumulation were confirmed by hybrid μCT-FMT imaging using near-infrared labeled micelles and payload. The PTX-loaded micelles were well tolerated at different doses while they induced complete tumor regression in two different xenograft models (i.e. A431 and MDA-MB-468). Our findings consequently indicate that π-π stacking-stabilized polymeric micelles are promising carriers to improve the delivery of highly hydrophobic drugs to tumors and to increase their therapeutic index. PMID:25831471

  20. Clinically Relevant Anticancer Polymer Paclitaxel Therapeutics

    PubMed Central

    Yang, Danbo; Yu, Lei; Van, Sang

    2011-01-01

    The concept of utilizing polymers in drug delivery has been extensively explored for improving the therapeutic index of small molecule drugs. In general, polymers can be used as polymer-drug conjugates or polymeric micelles. Each unique application mandates its own chemistry and controlled release of active drugs. Each polymer exhibits its own intrinsic issues providing the advantage of flexibility. However, none have as yet been approved by the U.S. Food and Drug Administration. General aspects of polymer and nano-particle therapeutics have been reviewed. Here we focus this review on specific clinically relevant anticancer polymer paclitaxel therapeutics. We emphasize their chemistry and formulation, in vitro activity on some human cancer cell lines, plasma pharmacokinetics and tumor accumulation, in vivo efficacy, and clinical outcomes. Furthermore, we include a short review of our recent developments of a novel poly(l-γ-glutamylglutamine)-paclitaxel nano-conjugate (PGG-PTX). PGG-PTX has its own unique property of forming nano-particles. It has also been shown to possess a favorable profile of pharmacokinetics and to exhibit efficacious potency. This review might shed light on designing new and better polymer paclitaxel therapeutics for potential anticancer applications in the clinic. PMID:24212604

  1. Stathmin potentiates vinflunine and inhibits Paclitaxel activity.

    PubMed

    Malesinski, Soazig; Tsvetkov, Philipp O; Kruczynski, Anna; Peyrot, Vincent; Devred, François

    2015-01-01

    Cell biology and crystallographic studies have suggested a functional link between stathmin and microtubule targeting agents (MTAs). In a previous study we showed that stathmin increases vinblastine (VLB) binding to tubulin, and that conversely VLB increases stathmin binding to tubulin. This constituted the first biochemical evidence of the direct relationship between stathmin and an antimitotic drug, and revealed a new mechanism of action for VLB. The question remained if the observed interaction was specific for this drug or represented a general phenomenon for all MTAs. In the present study we investigated the binding of recombinant stathmin to purified tubulin in the presence of paclitaxel or another Vinca alkaloid, vinflunine, using Isothermal Titration Calorimetry (ITC). These experiments revealed that stathmin binding to tubulin is increased in the presence of vinflunine, whereas no signal is observed in the presence of paclitaxel. Further investigation using turbidity and co-sedimentation showed that stathmin inhibited paclitaxel microtubule-stabilizing activity. Taken together with the previous study using vinblastine, our results suggest that stathmin can be seen as a modulator of MTA activity and binding to tubulin, providing molecular explanation for multiple previous cellular and in vivo studies showing that stathmin expression level affects MTAs efficiency. PMID:26030092

  2. Stathmin Potentiates Vinflunine and Inhibits Paclitaxel Activity

    PubMed Central

    Malesinski, Soazig; Tsvetkov, Philipp O.; Kruczynski, Anna; Peyrot, Vincent; Devred, François

    2015-01-01

    Cell biology and crystallographic studies have suggested a functional link between stathmin and microtubule targeting agents (MTAs). In a previous study we showed that stathmin increases vinblastine (VLB) binding to tubulin, and that conversely VLB increases stathmin binding to tubulin. This constituted the first biochemical evidence of the direct relationship between stathmin and an antimitotic drug, and revealed a new mechanism of action for VLB. The question remained if the observed interaction was specific for this drug or represented a general phenomenon for all MTAs. In the present study we investigated the binding of recombinant stathmin to purified tubulin in the presence of paclitaxel or another Vinca alkaloid, vinflunine, using Isothermal Titration Calorimetry (ITC). These experiments revealed that stathmin binding to tubulin is increased in the presence of vinflunine, whereas no signal is observed in the presence of paclitaxel. Further investigation using turbidity and co-sedimentation showed that stathmin inhibited paclitaxel microtubule-stabilizing activity. Taken together with the previous study using vinblastine, our results suggest that stathmin can be seen as a modulator of MTA activity and binding to tubulin, providing molecular explanation for multiple previous cellular and in vivo studies showing that stathmin expression level affects MTAs efficiency. PMID:26030092

  3. Metabolic alterations in K562 cells exposed to taxol and tyrphostin AG957: 1H NMR and biochemical studies.

    PubMed

    Knijn, Arno; Brisdelli, Fabrizia; Ferretti, Amalia; Iorio, Egidio; Marcheggiani, Donatella; Bozzi, Argante

    2005-11-01

    K562 cells exposed for 3 h to taxol or taxol plus tyrphostin AG957 exhibited a significant variation in the concentration of the water-soluble metabolites glutathione, myo-inositol and phosphorylcholine, as evaluated by (1)H NMR up to 72 h incubation in drug-free medium. Cells treated with both drugs showed an increase of glutathione and glutathione reductase at 24 h and a sharp decrease of myo-inositol between 8 and 24 h. Phosphorylcholine increased at 8 h both in taxol and taxol plus AG957-treated cells, which was then abruptly inverted to a significantly lower concentration at 24 h, subsequently increasing again to values higher than those found in taxol-treated and control cells. All the above reported effects were lacking in cells exposed to AG957 alone. These modifications, despite the enhancement of the overall apoptotic cascade in taxol plus AG957-treated cells, can be related to the activation of cellular detoxification mechanisms, to the correct osmolarity maintenance, and to alterations of phospholipid metabolism. PMID:16181795

  4. Isolation and identification of an anticancer drug, taxol from Phyllosticta tabernaemontanae, a leaf spot fungus of an angiosperm, Wrightia tinctoria.

    PubMed

    Kumaran, Rangarajulu Senthil; Muthumary, Johnpaul; Hur, Byung-Ki

    2009-02-01

    Phyllosticta tabernaemontanae, a leaf spot fungus isolated from the diseased leaves of Wrightia tinctoria, showed the production of taxol, an anticancer drug, on modified liquid medium (M1D) and potato dextrose broth (PDB) medium in culture for the first time. The presence of taxol was confirmed by spectroscopic and chromatographic methods of analysis. The amount of taxol produced by this fungus was quantified using high performance liquid chromatography (HPLC). The maximum amount of taxol production was recorded in the fungus grown on M1D medium (461 microg/L) followed by PDB medium (150 microg/L). The production rate was increased to 9.2 x 10(3) fold than that found in the culture broth of earlier reported fungus, Taxomyces andreanae. The results designate that P. tabernaemontanae is an excellent candidate for taxol production. The fungal taxol extracted also showed a strong cytotoxic activity in the in vitro culture of tested human cancer cells by apoptotic assay. PMID:19229490

  5. Combinatorial influences of paclitaxel and strain on axonal transport.

    PubMed

    Bober, Brian G; Gutierrez, Edgar; Plaxe, Steven; Groisman, Alex; Shah, Sameer B

    2015-09-01

    Paclitaxel is an effective chemotherapeutic agent that, despite its common use, often causes peripheral sensory neuropathy. In neurons, paclitaxel binds to and stabilizes microtubules, and through unknown mechanisms, bundles microtubules and disrupts their organization. Because microtubules serve as tracks on which a variety of axonal cargoes are transported, a leading hypothesis for the etiology of paclitaxel-induced neuropathy is that these changes to microtubule organization impair axonal transport. In addition to supporting transport, microtubules also serve a structural role, accommodating axonal extension occurring during axonal growth or joint movement. In light of this dual role for microtubules, we tested the hypothesis that axonal stretch amplified the effects of paclitaxel on axonal transport. Embryonic rat dorsal root ganglia were cultured on stretchable silicone substrates, and parameters describing the axonal transport of three distinct cargoes--mitochondria, synaptophysin, and actin--were measured with and without paclitaxel treatment and axonal strain. Paclitaxel treatment, particularly in combination with stretch, led to severe perturbations in several transport parameters, including the number, velocity, and travel distance of cargoes in the axon. Our results suggest that mechanical loading of neurons can exacerbate transport deficits associated with paclitaxel treatment, raising the interesting possibility that paclitaxel influences neuronal function in a multi-factorial manner. PMID:26143110

  6. Electrochemical determination of the anticancer drug taxol at a ds-DNA modified pencil-graphite electrode and its application as a label-free electrochemical biosensor.

    PubMed

    Tajik, Somayeh; Taher, Mohammad Ali; Beitollahi, Hadi; Torkzadeh-Mahani, Mosoud

    2015-03-01

    In this study a novel biosensor for determination of taxol is described. The interaction of taxol with salmon-sperm double-stranded DNA (ds-DNA) based on the decreasing of the oxidation signals of guanine and adenine bases was studied electrochemically with a pencil-graphite electrode (PGE) using a differential pulse voltammetry (DPV) method. The decreases in the intensity of the guanine and adenine oxidation signals after interaction with taxol were used as indicator signals for the sensitive determination of taxol. DPV exhibits a linear dynamic range of 2.0×10(-7)-1.0×10(-5) M for taxol with a detection limit of 8.0×10(-8) M. Finally, this modified electrode was used for determination of taxol in some real samples. PMID:25618641

  7. Improved anti-glioblastoma efficacy by IL-13Rα2 mediated copolymer nanoparticles loaded with paclitaxel

    PubMed Central

    Wang, Baoyan; Lv, Lingyan; Wang, Zhi; Jiang, Yan; Lv, Wei; Liu, Xin; Wang, Zhongyuan; Zhao, Yue; Xin, Hongliang; Xu, Qunwei

    2015-01-01

    Glioma presents one of the most malignant brain tumors, and the therapeutic effect is often limited due to the existence of brain tumor barrier. Based on interleukin-13 receptor α2 (IL-13Rα2) over-expression on glioma cell, it was demonstrated to be a potential receptor for glioma targeting. In this study, Pep-1-conjugated PEGylated nanoparticles loaded with paclitaxel (Pep-NP-PTX) were developed as a targeting drug delivery system for glioma treatment. The Pep-NP-PTX presented satisfactory size of 95.78 nm with narrow size distribution. Compared with NP-PTX, Pep-NP-PTX exhibited significantly enhanced cellular uptake in C6 cells (p < 0.001). The in vitro anti-proliferation evaluation showed that the IC50 were 146 ng/ml and 349 ng/ml of Pep-NP-PTX and NP-PTX, respectively. The in vivo fluorescent image results indicated that Pep-NP had higher specificity and efficiency in intracranial tumor accumulation. Following intravenous administration, Pep-NP-PTX could enhance the distribution of PTX in vivo glioma section, 1.98, 1.91 and 1.53-fold over that of NP-PTX group after 0.5, 1 and 4 h, respectively. Pep-NP-PTX could improve the anti-glioma efficacy with a median survival time of 32 days, which was significantly longer than that of PTX-NP (23 days) and Taxol® (22 days). In conclusion, Pep-NP-PTX is a potential targeting drug delivery system for glioma treatment. PMID:26567528

  8. Improving paclitaxel delivery: in vitro and in vivo characterization of PEGylated polyphosphoester-based nanocarriers.

    PubMed

    Zhang, Fuwu; Zhang, Shiyi; Pollack, Stephanie F; Li, Richen; Gonzalez, Amelia M; Fan, Jingwei; Zou, Jiong; Leininger, Sarah E; Pavía-Sanders, Adriana; Johnson, Rachel; Nelson, Laura D; Raymond, Jeffery E; Elsabahy, Mahmoud; Hughes, Dennis M P; Lenox, Mark W; Gustafson, Tiffany P; Wooley, Karen L

    2015-02-11

    Nanomaterials have great potential to offer effective treatment against devastating diseases by providing sustained release of high concentrations of therapeutic agents locally, especially when the route of administration allows for direct access to the diseased tissues. Biodegradable polyphosphoester-based polymeric micelles and shell cross-linked knedel-like nanoparticles (SCKs) have been designed from amphiphilic block-graft terpolymers, PEBP-b-PBYP-g-PEG, which effectively incorporate high concentrations of paclitaxel (PTX). Well-dispersed nanoparticles physically loaded with PTX were prepared, exhibiting desirable physiochemical characteristics. Encapsulation of 10 wt% PTX, into either micelles or SCKs, allowed for aqueous suspension of PTX at concentrations up to 4.8 mg/mL, as compared to <2.0 μg/mL for the aqueous solubility of the drug alone. Drug release studies indicated that PTX released from these nanostructures was defined through a structure-function relationship, whereby the half-life of sustained PTX release was doubled through cross-linking of the micellar structure to form SCKs. In vitro, physically loaded micellar and SCK nanotherapeutics demonstrated IC50 values against osteosarcoma cell lines, known to metastasize to the lungs (CCH-OS-O and SJSA), similar to the pharmaceutical Taxol formulation. Evaluation of these materials in vivo has provided an understanding of the effects of nanoparticle structure-function relationships on intratracheal delivery and related biodistribution and pharmacokinetics. Overall, we have demonstrated the potential of these novel nanotherapeutics toward future sustained release treatments via administration directly to the sites of lung metastases of osteosarcoma. PMID:25629952

  9. Biodistribution and Bioimaging Studies of Hybrid Paclitaxel Nanocrystals: Lessons Learned of the EPR Effect and Image-Guided Drug Delivery

    PubMed Central

    Hollis, Christin P.; Weiss, Heidi L.; Leggas, Markos; Evers, B. Mark; Gemeinhart, Richard A.; Li, Tonglei

    2013-01-01

    Paclitaxel (PTX) nanocrystals (200 nm) were produced by crystallization from solution. Antitumor efficacy and toxicity were examined through a survival study in a human HT-29 colon cancer xenograft murine model. The antitumor activity of the nanocrystal treatments was comparable with that by the conventional solubilization formulation (Taxol®), but yielded less toxicity as indicated by the result of survival study. Tritium-labeled PTX nanocrystals were further produced with a near infrared (NIR) fluorescent dye physically integrated in the crystal lattice. Biodistribution and tumor accumulation of the tritium-labeled PTX nanocrystals were determined immediately after intravenous administration and up to 48 hours by scintillation counting. Whole-body optical imaging of animals was concurrently carried out; fluorescent intensities were also measured from excised tumors and major organs of euthanized animals. It was found that drug accumulation in the tumor was less than 1% of 20 mg/kg intravenous dose. Qualitatively correlation was identified between the biodistribution determined by using tritium-labeled particles and that using optical imaging, but quantitative divergence existed. The divergent results suggest possible ways to improve the design of hybrid nanocrystals for cancer therapy and diagnosis. The study also raises questions of the general role of the enhanced permeability and retention (EPR) effect in tumor targeting and the effectiveness of bioimaging, specifically for hybrid nanocrystals, in tracking drug distribution and pharmacokinetics. PMID:23920039

  10. The influence of the combined treatment with Vadimezan (ASA404) and taxol on the growth of U251 glioblastoma xenografts

    PubMed Central

    2012-01-01

    Background One of the most important biological characteristics of Glioblastoma multiforme (GBM) is high vascular density. Vadimezan (ASA404, DMXAA) belongs to the class of small molecule vascular disrupting agents (VDA) that cause disruption of established tumor vessels and subsequent tumor hemorrhagic necrosis. Its selective antivascular effect is mediated by intratumoral induction of several cytokines including tumor necrosis factor-α (TNF-α), granulocyte-colony-stimulating factor (G-CSF), interleukin 6 (IL-6) and macrophage inflammatory protein 1α (MIP-1α). Preclinical studies have demonstrated that ASA404 acts synergistically with taxanes. In this study, we investigated if treatment of mice bearing U251 human glioblastoma xenografts with ASA404 and taxol may be synergistic. Therapy response was evaluated by measuring changes in tumor size and metabolic activity using 18F-FDG PET (Fluorodeoxyglucose - positron emision tomography) imaging. Methods U251 cells were inoculated s.c. in the right hind limb of NMRI-Foxn1nu athymic female nude mice. Animals were randomly assigned into 4 groups (7–9 animals/group) for treatment: control, taxol, ASA404, and ASA404 plus taxol. The animals received either a single dose of taxol (10 mg/kg), ASA404 (27.5 mg/kg), or taxol (10 mg/kg) plus ASA404 (27.5 mg/kg) administered i.p.; ASA404 was administred 24 h after the treatment with taxol. 4 and 24 h after treatment with ASA404 (28 and 48 h hours after treatment with taxol) 18 F-FDG PET scans were performed. Results The treatment with taxol did not affect the tumor growth in comparison to untreated controls. The treatment of animals with single dose ASA404 alone or in combination with taxol caused a significant delay in tumor growth. The combined treatment did not decrease the growth of the xenografts significantly more than ASA404 alone, but early changes in tumor 18 F-FDG uptake preceded subsequent growth inhibition. The tumor weights, which were determined at the end of treatment, were lower in case of combined treatment. Conclusions The treatment with ASA404 alone or in combination with taxol showed antitumoral effects in our glioblastoma model probably through destruction of blood vessels. The implications for the anticancer effect of this compound warrant further preclinical studies. 18F-FDG PET appears to be a promising tool to monitor treatment with ASA404 early in the course of therapy. PMID:22695475

  11. The Development and Maintenance of Paclitaxel-induced Neuropathic Pain Require Activation of the Sphingosine 1-Phosphate Receptor Subtype 1*

    PubMed Central

    Janes, Kali; Little, Joshua W.; Li, Chao; Bryant, Leesa; Chen, Collin; Chen, Zhoumou; Kamocki, Krzysztof; Doyle, Timothy; Snider, Ashley; Esposito, Emanuela; Cuzzocrea, Salvatore; Bieberich, Erhard; Obeid, Lina; Petrache, Irina; Nicol, Grant; Neumann, William L.; Salvemini, Daniela

    2014-01-01

    The ceramide-sphingosine 1-phosphate (S1P) rheostat is important in regulating cell fate. Several chemotherapeutic agents, including paclitaxel (Taxol), involve pro-apoptotic ceramide in their anticancer effects. The ceramide-to-S1P pathway is also implicated in the development of pain, raising the intriguing possibility that these sphingolipids may contribute to chemotherapy-induced painful peripheral neuropathy, which can be a critical dose-limiting side effect of many widely used chemotherapeutic agents. We demonstrate that the development of paclitaxel-induced neuropathic pain was associated with ceramide and S1P formation in the spinal dorsal horn that corresponded with the engagement of S1P receptor subtype 1 (S1PR1)-dependent neuroinflammatory processes as follows: activation of redox-sensitive transcription factors (NFκB) and MAPKs (ERK and p38) as well as enhanced formation of pro-inflammatory and neuroexcitatory cytokines (TNF-α and IL-1β). Intrathecal delivery of the S1PR1 antagonist W146 reduced these neuroinflammatory processes but increased IL-10 and IL-4, potent anti-inflammatory/neuroprotective cytokines. Additionally, spinal W146 reversed established neuropathic pain. Noteworthy, systemic administration of the S1PR1 modulator FTY720 (Food and Drug Administration-approved for multiple sclerosis) attenuated the activation of these neuroinflammatory processes and abrogated neuropathic pain without altering anticancer properties of paclitaxel and with beneficial effects extended to oxaliplatin. Similar effects were observed with other structurally and chemically unrelated S1PR1 modulators (ponesimod and CYM-5442) and S1PR1 antagonists (NIBR-14/15) but not S1PR1 agonists (SEW2871). Our findings identify for the first time the S1P/S1PR1 axis as a promising molecular and therapeutic target in chemotherapy-induced painful peripheral neuropathy, establish a mechanistic insight into the biomolecular signaling pathways, and provide the rationale for the clinical evaluation of FTY720 in chronic pain patients. PMID:24876379

  12. Decreased gap junctional communication in neurobiotin microinjected lens epithelial cells after taxol treatment.

    PubMed

    Giessmann, Daniel; Theiss, Carsten; Breipohl, Winrich; Meller, Karl

    2005-06-01

    The aim of the study was to examine gap-junction-mediated intercellular communication after experimentally induced aggregations of microtubules in cultured bovine lens epithelial cells. Intercellular communication between lens cells appears to be crucial for normal lens homeostasis. However, investigations on the maintenance of direct ion and metabolite exchange via gap junctions and its quantified dependency of cytoskeletal microtubules have not been available under conditions leading to bundling of microtubules. Thus, metabolic coupling of neighboring lens epithelial cells was quantified following microinjections of neurobiotin into single cells under various conditions. In controls, intensive gap-junction-mediated intercellular communication could be documented by dye-spreading of microinjected neurobiotin. In contrast, taxol treatment for 1-3 days impaired, but did not completely block gap-junction-mediated intercellular communication. After depletion of taxol, a complete recovery of intercellular communication was achieved. In addition, confocal laser scanning microscopy and rapid-freeze deep-etch electron microscopy revealed a displacement of actin-filaments from the perinuclear cytoplasm, accompanied by an abnormal aggregation of microtubules after taxol treatment, including impeded translocation of connexin 43 from the cytoplasm into the plasma membrane. Incubation of cells with nocodazole destroyed the microtubule network, accompanied by a clear reduction of plasma-membrane-integrated connexin 43 and significant impairment of dye spreading. Thus, in lens epithelial cells intercellular communication at gap junctions made by connexin 43 depends on the integrity of the microtubule network through the translocation of connexins to the plasma membrane. PMID:15864639

  13. Paclitaxel targets FOXM1 to regulate KIF20A in mitotic catastrophe and breast cancer paclitaxel resistance.

    PubMed

    Khongkow, P; Gomes, A R; Gong, C; Man, E P S; Tsang, J W-H; Zhao, F; Monteiro, L J; Coombes, R C; Medema, R H; Khoo, U S; Lam, E W-F

    2016-02-25

    FOXM1 has been implicated in taxane resistance, but the molecular mechanism involved remains elusive. In here, we show that FOXM1 depletion can sensitize breast cancer cells and mouse embryonic fibroblasts into entering paclitaxel-induced senescence, with the loss of clonogenic ability, and the induction of senescence-associated β-galactosidase activity and flat cell morphology. We also demonstrate that FOXM1 regulates the expression of the microtubulin-associated kinesin KIF20A at the transcriptional level directly through a Forkhead response element (FHRE) in its promoter. Similar to FOXM1, KIF20A expression is downregulated by paclitaxel in the sensitive MCF-7 breast cancer cells and deregulated in the paclitaxel-resistant MCF-7Tax(R) cells. KIF20A depletion also renders MCF-7 and MCF-7Tax(R) cells more sensitive to paclitaxel-induced cellular senescence. Crucially, resembling paclitaxel treatment, silencing of FOXM1 and KIF20A similarly promotes abnormal mitotic spindle morphology and chromosome alignment, which have been shown to induce mitotic catastrophe-dependent senescence. The physiological relevance of the regulation of KIF20A by FOXM1 is further highlighted by the strong and significant correlations between FOXM1 and KIF20A expression in breast cancer patient samples. Statistical analysis reveals that both FOXM1 and KIF20A protein and mRNA expression significantly associates with poor survival, consistent with a role of FOXM1 and KIF20A in paclitaxel action and resistance. Collectively, our findings suggest that paclitaxel targets the FOXM1-KIF20A axis to drive abnormal mitotic spindle formation and mitotic catastrophe and that deregulated FOXM1 and KIF20A expression may confer paclitaxel resistance. These findings provide insights into the underlying mechanisms of paclitaxel resistance and have implications for the development of predictive biomarkers and novel chemotherapeutic strategies for paclitaxel resistance. PMID:25961928

  14. Interactions between Co-Habitating fungi Elicit Synthesis of Taxol from an Endophytic Fungus in Host Taxus Plants

    PubMed Central

    Soliman, Sameh S. M.; Raizada, Manish N.

    2012-01-01

    Within a plant, there can exist an ecosystem of pathogens and endophytes, the latter described as bacterial and fungal inhabitants that thrive without causing disease to the host. Interactions between microbial inhabitants represent a novel area of study for natural products research. Here we analyzed the interactions between the fungal endophytes of Taxus (yew) trees. Fungal endophytes of Taxus have been proposed to produce the terpenoid secondary metabolite, Taxol, an anti-cancer drug. It is widely reported that plant extracts stimulate endophytic fungal Taxol production, but the underlying mechanism is not understood. Here, Taxus bark extracts stimulated fungal Taxol production 30-fold compared to a 10-fold induction with wood extracts. However, candidate plant-derived defense compounds (i.e., salicylic acid, benzoic acid) were found to act only as modest elicitors of fungal Taxol production from the endophytic fungus Paraconiothyrium SSM001, consistent with previous studies. We hypothesized the Taxus plant extracts may contain elicitors derived from other microbes inhabiting these tissues. We investigated the effects of co-culturing SSM001 with other fungi observed to inhabit Taxus bark, but not wood. Surprisingly, co-culture of SSM001 with a bark fungus (Alternaria) caused a ∼threefold increase in Taxol production. When SSM001 was pyramided with both the Alternaria endophyte along with another fungus (Phomopsis) observed to inhabit Taxus, there was an ∼eightfold increase in fungal Taxol production from SSM001. These results suggest that resident fungi within a host plant interact with one another to stimulate Taxol biosynthesis, either directly or through their metabolites. More generally, our results suggest that endophyte secondary metabolism should be studied in the context of its native ecosystem. PMID:23346084

  15. Development of paclitaxel-TyroSpheres for topical skin treatment

    PubMed Central

    Kilfoyle, Brian E.; Sheihet, Larisa; Zhang, Zheng; Laohoo, Marissa; Kohn, Joachim; Michniak-Kohn, Bozena B.

    2012-01-01

    A potential topical psoriasis therapy has been developed consisting of tyrosine-derived nanospheres (TyroSpheres) with encapsulated anti-proliferative paclitaxel. TyroSpheres provide enhancement of paclitaxel solubility (almost 4,000 times greater than PBS) by effective encapsulation and enable sustained, dose-controlled release over 72 hours under conditions mimicking skin permeation. TyroSpheres offer potential in the treatment of psoriasis, a disease resulting from over-proliferation of keratinocytes in the basal layer of the epidermis, by (a) enabling delivery of paclitaxel into the epidermis at concentrations >100 ng/cm2 of skin surface area and (b) enhancing the cytotoxicity of loaded paclitaxel to human keratinocytes (IC50 of paclitaxel-TyroSpheres was approximately 45% lower than that of free paclitaxel). TyroSpheres were incorporated into a gel-like viscous formulation to improve their flow characteristics with no impact on homogeneity, release or skin distribution of the payload. The findings reported here confirm that the TyroSpheres provide a platform for paclitaxel topical administration allowing skin drug localization and minimal systemic escape. PMID:22732474

  16. Identification of pathways involved in paclitaxel activity in cervical cancer.

    PubMed

    Qiao, Wen-Juan; Cheng, Hai-Yan; Li, Chun-Quan; Jin, Hong; Yang, Shan-Shan; Li, Xia; Zhang, Yun-Yan

    2011-01-01

    Paclitaxel is one of the key chemotherapeutic drugs widely used to treat various types of cancer. Many cervical cancer patients exhibit selectivity in response to thereapy, however, which is considered to be correlated with drug-gene-pathways. The aim of this study was to identify pathways involved in paclitaxel activity in cervical cancer. Gene expression data was obtained from the NCBI Gene Expression Omnibus and the associations between paclitaxel and genes from DrugBank, MATADOR, TTD, CTD and SuperTarget databases. Differentially expressed genes in cervical cancer were identified using the significance analysis of microarrays (SAM) statistical technique. Pathway analysis was performed according to the Kyoto Encyclopedia of Genes and Genomes (KEGG) database using the software package SubpathwayMiner to predict target genes of paclitaxel in cervical cancer and regulated pathways. We found that paclitaxel, which exhibits anticancer activity in cervical cancer, may interact with these differentially expressed genes and their corresponding signaling pathways. Our study presents the first in-depth, large-scale analysis of pathways involved in paclitaxel activity in cervical cancer. Interestingly, these pathways have not been reported to be involved in other tumors. Thus our findings may contribute to the understanding of the mechanisms underlying paclitaxel resistance in cervical cancer. PMID:21517239

  17. Gene expression profiling of taxol-resistant nasopharyngeal carcinoma cells with siRNA-mediated FOLR1 downregulation

    PubMed Central

    Song, Yexun; Peng, Xiaowei; Wang, Min; Xie, Jun; Tan, Guolin

    2015-01-01

    Objectives: Our previous study has shown that downregulation of FOLR1 by siRNA partially reversed taxol-resistant phenotype in taxol-resistant nasopharyngeal carcinoma cell lines. We aim to gain further insight into the molecular mechanisms of this process and identify the differentially expressed genes after FOLR1 downregulation. Method: The global gene expression profile was identified and analyzed using the Affymetrix HG-U133 Plus 2.0 array. Results: There was a significant dysregulation in the global gene expression of the FOLR1-suppressed taxol-resistant nasopharyngeal carcinoma cell lines. There were 41 upregulated genes and 109 downregulated genes. QRT-PCR validation of the selected differentially expressed genes demonstrated there was a good correlation with the microarray analysis. There was a significant deregulation of expression in the apoptosis-related genes such as BIRC3, PRKX, TNFRSF10A and involved in Viral carcinogenesis, MAPK signaling pathways after FOLR1 was downregulated. Conclusion: The suppression of FOLR1 by RNA interference altered gene expression profile of taxol-resistant nasopharyngeal carcinoma cell lines. The apoptosis-related genes and the gene alterations in viral carcinogenesis, MAPK signaling pathways might be important in FOLR1 siRNA-induced taxol-resistant reversal. PMID:26617855

  18. Anti-proliferative effect of fungal taxol extracted from Cladosporium oxysporum against human pathogenic bacteria and human colon cancer cell line HCT 15

    NASA Astrophysics Data System (ADS)

    Gokul Raj, K.; Manikandan, R.; Arulvasu, C.; Pandi, M.

    2015-03-01

    Cladosporium oxysporum a new taxol producing endophytic fungus was identified and production of taxol were characterized using UV-visible spectroscopy (UV-vis), high-performance liquid chromatography (HPLC), infrared (IR) nuclear magnetic resonance spectroscopy (NMR (13C and 1H)) and liquid chromatography-mass spectrometry (LC-MS). The taxol biosynthetic gene (dbat) was evaluated for new taxol producing fungus. Antibacterial activity against six different human pathogenic bacteria was done by agar well diffusion method. The anticancer efficacy of isolated fungal taxol were also evaluated in human colon cancer cell HCT 15 by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), cytotoxicity and nuclear morphology analysis. The isolated fungal taxol showed positive towards biosynthetic gene (dbat) and effective against both Gram positive as well as Gram negative. The fungal taxol suppress growth of cancer cell line HCT 15 with an IC50 value of 3.5 μM concentration by 24 h treatment. Thus, the result reveals that C. oxysporum could be a potential alternative source for production of taxol and have antibacterial as well as anticancer properties with possible clinical applications.

  19. Nature as a Remarkable Chemist: A Personal Story of the Discovery and Development of Taxol®

    PubMed Central

    Wani, Mansukh C.; Horwitz, Susan Band

    2014-01-01

    The development of a new anticancer drug with a novel structure and unique mechanism of action is an important event, especially when the drug has a clear role in improving the outcome for cancer patients. No drug fits this description better than Taxol®. However, during the early phases of its development there was little interest in the drug, particularly by the medical community. The story of Taxol® is long and fascinating, and includes many examples in which the drug could have been dropped, resulting in its antitumor activity never being available to patients. It was 21 years between the original landmark paper on the isolation and structural determination of Taxol® [1] and its approval in 1992 by the FDA for its use in the treatment of ovarian cancer. PMID:24413390

  20. Neoadjuvant nab-paclitaxel in the treatment of breast cancer.

    PubMed

    Ueno, Naoto T; Mamounas, Eleftherios P

    2016-04-01

    Neoadjuvant chemotherapy has the advantage of converting unresectable breast tumors to resectable tumors and allowing more conservative surgery in some mastectomy candidates. Chemotherapy agents, including taxanes, which are recommended in the adjuvant setting, are also considered in the neoadjuvant setting. Here, we review studies of nab-paclitaxel as a neoadjuvant treatment for patients with breast cancer. PubMed and conference or congress proceedings were searched for clinical studies of nab-paclitaxel in the neoadjuvant treatment of breast cancer. We also searched ClinicalTrials.gov for ongoing trials of nab-paclitaxel as a neoadjuvant agent in breast cancer. Twenty studies of nab-paclitaxel in the neoadjuvant setting were identified. In addition to reviewing key efficacy and safety data, we discuss how each trial assessed response, focusing on pathologic complete response and residual cancer burden scoring. Safety profiles are also reviewed. nab-Paclitaxel demonstrated antitumor activity and an acceptable safety profile in the neoadjuvant treatment of breast cancer. Ongoing and future trials will further evaluate preoperative nab-paclitaxel in breast cancer, including in combination with many novel immunological targeted therapies. PMID:27072366

  1. Paclitaxel inhibits mRNA transport in axons.

    PubMed

    Bobylev, Ilja; Joshi, Abhijeet R; Barham, Mohammed; Ritter, Christian; Neiss, Wolfram F; Höke, Ahmet; Lehmann, Helmar C

    2015-10-01

    Paclitaxel is an integral component of solid tumor treatment. This chemotherapeutic agent provokes an often irreversible peripheral sensory neuropathy with pathological features of distal axonal degeneration. Current pathological concepts assume that polymerization of axonal microtubules and mitochondrial dysfunction contributes to the development of paclitaxel-induced peripheral neuropathy. The relationship, however, between microtubule stabilization, mitotoxicity and axonal degeneration is still not completely understood. To explore the function of axonal mitochondria we treated transgenic mice that harbor cyan fluorescent protein (CFP)-labeled neuronal mitochondria with repeated doses of paclitaxel and assessed neuropathic changes by nerve conduction and histological studies. In addition, mitochondrial content and morphology was determined by ex vivo imaging of axons containing CFP-labeled mitochondria. Using quantitative RT-PCR and fluorescence-labeled mRNA we determined axonal mRNA transport of nuclear encoded mitochondrial proteins. Prolonged treatment with high doses of paclitaxel-induced a predominant sensory neuropathy in mice. Although mitochondrial velocity in axons per se was not altered, we observed significant changes in mitochondrial morphology, suggesting that paclitaxel treatment impairs the dynamics of axonal mitochondria. These changes were caused by decreased levels of nuclear encoded mRNA, including the mitochondrial fusion/fission machinery. Moreover, impaired axonal mRNA transport in vitro resulted in mitochondrial dysfunction and subsequent axonal degeneration. Taken together, our experiments provide evidence that disrupted axonal transport of nuclear derived mRNA plays a crucial role in the pathogenesis of paclitaxel-induced sensory neuropathy. PMID:26188177

  2. Paclitaxel uptake and transport in Taxus cell suspension cultures

    PubMed Central

    Naill, Michael C.; Kolewe, Martin E.; Roberts, Susan C.

    2012-01-01

    The transport of paclitaxel in Taxus canadensis suspension cultures was studied with a fluorescence analogue of paclitaxel (Flutax-2®) in combination with flow cytometry detection. Experiments were carried out using both isolated protoplasts and aggregated suspension cell cultures. Flutax-2® was shown to be greater than 90% stable in Taxus suspension cultures over the required incubation time (24 hours). Unlabeled paclitaxel was shown to inhibit the cellular uptake of Flutax-2®, although structurally similar taxanes such as cephalomannine, baccatin III, and 10-deacetylbaccatin III did not inhibit Flutax-2® uptake. Saturation kinetics of Flutax-2® uptake was demonstrated. These results indicate the presence of a specific transport system for paclitaxel. Suspension cells elicited with methyl jasmonate accumulated 60% more Flutax-2® than unelicited cells, possibly due to an increased cellular storage capacity following methyl jasmonate elicitation. The presence of a specific mechanism for paclitaxel transport is an important first result that will provide the basis of more detailed studies as well as the development of targeted strategies for increased paclitaxel secretion to the extracellular medium. PMID:23180977

  3. Paclitaxel and docetaxel in prostate cancer.

    PubMed

    Obasaju, C; Hudes, G R

    2001-06-01

    Although their ultimate value in prostate cancer therapy remains to be defined in randomized trials, docetaxel and paclitaxel are active agents in HRPC. Combination therapies using either of these taxanes plus oral EMP show reproducible antitumor activity that appears to be greater and more durable than that of single-agent treatment. Although the optimal combination and schedule have not been determined, weekly paclitaxel and EMP and docetaxel given every 3 weeks or by weekly infusion with EMP are useful treatment options for patients with progressive HRPC. The gastrointestinal toxicity of EMP has been reduced by intermittent rather than continuous administration, and other toxicities may be reduced further by use of intravenous EMP. Although there has been progress, the median time to progression of 5 to 6 months for current taxane-based therapies suggests that they will not have major impact on overall survival for patients with HRPC. Greater benefit may be possible earlier in the course of prostate cancer, and the activity of the taxane-EMP combinations is sufficient to justify clinical trials of adjuvant or neoadjuvant chemotherapy for selected groups of patients with locally advanced and poor-prognosis tumors. Armed with many new molecularly targeted agents that may interact favorably with taxanes, it should be possible to build on current antimicrotubule regimens to improve activity in HRPC. Taxane-EMP combinations provide a platform on which to test additional agents that may enhance the apoptotic response or circumvent cellular stress adaptations that confer drug resistance. Further elucidation of signaling pathways that regulate microtubule dynamics and programmed cell death after exposure to microtubule inhibitors would provide a more rational guide for integrating specific inhibitors of signal transduction with current taxane-based therapies. Pharmacokinetic and pharmacodynamic studies will play a key role in the development of future taxane-based therapies for prostate cancer. PMID:11525295

  4. Janus nanogels of PEGylated Taxol and PLGA-PEG-PLGA copolymer for cancer therapy

    NASA Astrophysics Data System (ADS)

    Wei, Jun; Wang, Huaimin; Zhu, Meifeng; Ding, Dan; Li, Dongxia; Yin, Zhinan; Wang, Lianyong; Yang, Zhimou

    2013-09-01

    Nanogels are promising carriers for the delivery of anti-cancer drugs for cancer therapy. We report in this study on a Janus nanogel system formed by mixing a prodrug of Taxol (PEGylated Taxol) and a copolymer of PLGA-PEG-PLGA. The Janus nanogels have good stability over months in aqueous solutions and the freeze-dried powder of nanogels can be re-dispersed instantly in aqueous solutions. The Janus nanogels show an enhanced inhibition effect on tumor growth in a mice breast cancer model probably due to the enhanced uptake of the nano-sized materials by the EPR effect. What is more, the nanogels can also serve as physical carriers to co-deliver other anti-cancer drugs such as doxorubicin to further improve the anti-cancer efficacy. The results obtained from H&E staining and TUNEL assay also support the observation of tumor growth inhibition. These results suggest the potential of this novel delivery system for cancer therapy.Nanogels are promising carriers for the delivery of anti-cancer drugs for cancer therapy. We report in this study on a Janus nanogel system formed by mixing a prodrug of Taxol (PEGylated Taxol) and a copolymer of PLGA-PEG-PLGA. The Janus nanogels have good stability over months in aqueous solutions and the freeze-dried powder of nanogels can be re-dispersed instantly in aqueous solutions. The Janus nanogels show an enhanced inhibition effect on tumor growth in a mice breast cancer model probably due to the enhanced uptake of the nano-sized materials by the EPR effect. What is more, the nanogels can also serve as physical carriers to co-deliver other anti-cancer drugs such as doxorubicin to further improve the anti-cancer efficacy. The results obtained from H&E staining and TUNEL assay also support the observation of tumor growth inhibition. These results suggest the potential of this novel delivery system for cancer therapy. Electronic supplementary information (ESI) available: Synthesis and characterization of compounds, dynamic time sweep, H&E result and body weight change of mice. See DOI: 10.1039/c3nr02937a

  5. Studies on Taxol Biosynthesis: Preparation of Taxadiene-diol- and triol-Derivatives by Deoxygenation of Taxusin

    PubMed Central

    Li, Hui; Horiguchi, Tohru; Croteau, Rodney

    2008-01-01

    The putative taxol biosynthesis metabolites, taxa-4(20),11(12)-diene-5?, 13? -diol (7), taxa-4(20),11(12)-diene-5?, 9?, 13?-triol (9), and taxa-4(20),11(12)-diene-5?, 10?, 13?-triol (10), have been prepared by Barton deoxygenation of the C-9 and C10-hydroxyl groups of protected derivatives of taxusin, a major taxoid metabolite isolated from Yew heart wood. The synthetic protocol devised, is amenable for the preparation of isotopically labeled congeners that will be useful to probe further intermediate steps in the biosynthesis of taxol. PMID:19122848

  6. Effect of Ethyl Pyruvate on Paclitaxel-Induced Neuropathic Pain in Rats

    PubMed Central

    Choi, Seong Soo; Koh, Won Uk; Nam, Jae Sik; Shin, Jin Woo; Leem, Jeong Gill

    2013-01-01

    Background Although paclitaxel is a widely used chemotherapeutic agent for the treatment of solid cancers, side effects such as neuropathic pain lead to poor compliance and discontinuation of the therapy. Ethyl pyruvate (EP) is known to have analgesic effects in several pain models and may inhibit apoptosis. The present study was designed to investigate the analgesic effects of EP on mechanical allodynia and apoptosis in dorsal root ganglion (DRG) cells after paclitaxel administration. Methods Rats were randomly divided into 3 groups: 1) a control group, which received only vehicle; 2) a paclitaxel group, which received paclitaxel; and 3) an EP group, which received EP after paclitaxel administration. Mechanical allodynia was tested before and at 7 and 14 days after final paclitaxel administration. Fourteen days after paclitaxel treatment, DRG apoptosis was determined by activated caspase-3 immunoreactivity (IR). Results Post-treatment with EP did not significantly affect paclitaxel-induced allodynia, although it tended to slightly reduce sensitivities to mechanical stimuli after paclitaxel administration. After paclitaxel administration, an increase in caspase-3 IR in DRG cells was observed, which was co-localized with NF200-positive myelinated neurons. Post-treatment with EP decreased the paclitaxel-induced caspase-3 IR. Paclitaxel administration or post-treatment with EP did not alter the glial fibrillary acidic protein IRs in DRG cells. Conclusions Inhibition of apoptosis in DRG neurons by EP may not be critical in paclitaxel-induced mechanical allodynia. PMID:23614074

  7. Effect of several compounds on biliary excretion of paclitaxel and its metabolites in guinea-pigs.

    PubMed

    Bun, Sok-Siya; Giacometti, Sarah; Fanciullino, Raphalle; Ciccolini, Joseph; Bun, Hot; Aubert, Claude

    2005-07-01

    The objective of this study was to evaluate the in vivo metabolic profile of paclitaxel and to examine the effect of potential co-administered drugs on the biliary secretion of paclitaxel and its metabolites in guinea-pigs. We first investigated in vitro paclitaxel metabolism using liver microsomes obtained from various species to identify the most suitable animal model with a similar metabolism to humans. Then, in vivo paclitaxel metabolism was investigated in male guinea-pigs. The levels of paclitaxel and its metabolites were measured by high-performance liquid chromatography in bile samples from guinea-pigs after paclitaxel i.v. injection (6 mg/kg). We further evaluated the effects of various drugs (quercetin, ketoconazole, dexamethasone, cotrimoxazole) on the biliary secretion of paclitaxel and its metabolites in guinea-pigs. This work demonstrated significant in vitro interspecies differences in paclitaxel metabolism. Our findings showed both in vitro and in vivo similarities between human and guinea-pig biotransformation of paclitaxel. 6alpha-Hydroxypaclitaxel, the main human metabolite of paclitaxel, was found in guinea-pig bile. After paclitaxel combination with ketoconazole or quercetin in guinea-pigs, the cumulative biliary excretion of paclitaxel and its metabolites up to 6 h was significantly decreased by 62 and 76%, respectively. The co-administration of cotrimoxazole or pretreatment with dexamethasone did not alter significantly cumulative biliary excretion. The guinea-pig is a suitable model to study metabolism and biliary excretion of paclitaxel, and to investigate in vivo drug interactions. PMID:15930897

  8. Transformation of taxol-stabilized microtubules into inverted tubulin tubules triggered by a tubulin conformation switch

    PubMed Central

    Ginsburg, Avi; Kohl, Phillip A.; Li, Youli; Miller, Herbert P.; Wilson, Leslie; Raviv, Uri; Choi, Myung Chul; Safinya, Cyrus R.

    2014-01-01

    Bundles of taxol-stabilized microtubules (MTs) – hollow tubules comprised of assembled αβ-tubulin heterodimers – spontaneously assemble above a critical concentration of tetravalent spermine and are stable over long times at room temperature. Here we report that at concentrations of spermine several-fold higher the MT bundles (BMT) quickly become unstable and undergo a shape transformation to bundles of inverted tubulin tubules (BITT), the outside surface of which corresponds to the inner surface of the BMT tubules. Using transmission electron microscopy and synchrotron small-angle x-ray scattering, we quantitatively determined both the nature of the BMT to BITT transformation pathway, which results from a spermine-triggered conformation switch from straight to curved in the constituent taxol-stabilized tubulin oligomers, and the structure of the BITT phase, which is formed of tubules of helical tubulin oligomers. Inverted tubulin tubules provide a platform for studies requiring exposure and availability of the inside, luminal surface of MTs to MT-targeted-drugs and MT-associated-proteins. PMID:24441880

  9. Global functional analysis of nucleophosmin in Taxol response, cancer, chromatin regulation, and ribosomal DNA transcription

    SciTech Connect

    Bergstralh, Daniel T. . E-mail: dan.bergstralh@med.unc.edu; Conti, Brian J.; Moore, Chris B.; Brickey, W. June; Taxman, Debra J.; Ting, Jenny P.-Y.

    2007-01-01

    Analysis of lung cancer response to chemotherapeutic agents showed the accumulation of a Taxol-induced protein that reacted with an anti-phospho-MEK1/2 antibody. Mass spectroscopy identified the protein as nucleophosmin/B23 (NPM), a multifunctional protein with diverse roles: ribosome biosynthesis, p53 regulation, nuclear-cytoplasmic shuttling, and centrosome duplication. Our work demonstrates that following cellular exposure to mitosis-arresting agents, NPM is phosphorylated and its chromatographic property is altered, suggesting changes in function during mitosis. To determine the functional relevance of NPM, its expression in tumor cells was reduced by siRNA. Cells with reduced NPM were treated with Taxol followed by microarray profiling accompanied by gene/protein pathway analyses. These studies demonstrate several expected and unexpected consequences of NPM depletion. The predominant downstream effectors of NPM are genes involved in cell proliferation, cancer, and the cell cycle. In congruence with its role in cancer, NPM is over-expressed in primary malignant lung cancer tissues. We also demonstrate a role for NPM in the expression of genes encoding SET (TAF1{beta}) and the histone methylase SET8. Additionally, we show that NPM is required for a previously unobserved G2/M upregulation of TAF1A, which encodes the rDNA transcription factor TAF{sub I}48. These results demonstrate multi-faceted functions of NPM that can affect cancer cells.

  10. Choroidal neovascularization reduced by targeted drug delivery with cationic liposome-encapsulated paclitaxel or targeted photodynamic therapy with verteporfin encapsulated in cationic liposomes

    PubMed Central

    Gross, Nikolai; Ranjbar, Mahdy; Evers, Charlotte; Hua, Jing; Martin, Gottfried; Schulze, Brita; Michaelis, Uwe; Hansen, Lutz L.

    2013-01-01

    Purpose Intravitreal antivascular endothelial growth factor (anti-VEGF) application has revolutionized the treatment of choroidal neovascularization (CNV), a hallmark of wet age-related macular degeneration. However, additional treatment options are desirable as not all CNV lesions respond to anti-VEGF injections. Here, we assessed the feasibility of targeted delivery of cationic liposome-encapsulated paclitaxel (EndoTAG-1) in treating CNV. Furthermore, we investigated whether a new formulation of verteporfin encapsulated in cationic liposomes (CL-VTP) enhances the effect of photodynamic therapy (PDT). Methods EndoTAG-1, LipoSPA, and CL-VTP were produced by encapsulating paclitaxel, succinyl-paclitaxel, or verteporfin in cationic liposomes (CL). Mice underwent argon laser coagulations at day 0 (D0) to induce CNV. EndoTAG-1 and LipoSPA were injected into the tail vein at D1, D3, D5, D7, and D9. Taxol, CL, or trehalose buffer alone was injected in control animals. At D10, all animals were perfused with fluorescein isothiocyanate (FITC)-dextran. Flatmounts comprising the retinal pigment epithelium, choroid, and sclera were prepared for quantifying the CNV by measuring the area of lesions perfused with FITC-dextran. For PDT, mice received an injection with CL-VTP or Visudyne at D10. One eye was treated with PDT while the other served as a control. Evaluation of RPE-choroid-scleral and retinal flatmounts was performed at D12, D14, or D17. Perfusion with FITC-dextran and tetramethylrhodamine-5-(and 6)-isothiocyanate-lectin staining was used to distinguish between perfused and non-perfused choroidal vessels. Results EndoTAG-1 or LipoSPA significantly reduced CNV size to 15% compared to trehalose controls. The mean CNV area of mice treated with CL was reduced (though not significantly) to about one-half of the value of the trehalose control group. The same was observed for paclitaxel. Thus, the reduction in the CNV size between treatment with CL and treatment with EndoTAG-1 or LipoSPA was 40%, which was not significant. PDT using either CL-VTP or Visudyne reduced CNV size to 65% (D17) of trehalose control size. CNV size was further diminished to 56% with Visudyne and 53% with CL-VTP when PDT was repeated twice. Most importantly, PDT-associated retinal damage was less pronounced using CL-VTP compared to Visudyne. Conclusions Systemic intravenous injection of paclitaxel (EndoTAG-1)- or succinyl-paclitaxel (LipoSPA)-loaded CL had a significant antiangiogenic effect in a CNV mouse model. PDT with CL-VTP was as effective as Visudyne in neovascular obliteration but induced less tissue damage. Our data suggest that systemic application of cationic liposome formulations may serve to treat ocular neovascular diseases. This approach may reduce the need for intraocular injections and may benefit patients with neovascular lesions irresponsive to anti-VEGF treatment. PMID:23335851

  11. The flavonoid quercetin transiently inhibits the activity of taxol and nocodazole through interference with the cell cycle

    PubMed Central

    Samuel, Temesgen; Fadlalla, Khalda; Turner, Timothy; Yehualaeshet, Teshome E.

    2010-01-01

    Quercetin is a flavonoid with anticancer properties. In this study, we examined the effects of quercetin on cell cycle, viability and proliferation of cancer cells, either singly or in combination with the microtubule-targeting drugs taxol and nocodazole. Although quercetin induced cell death in a dose dependent manner, 12.5-50μM quercetin inhibited the activity of both taxol and nocodazole to induce G2/M arrest in various cell lines. Quercetin also partially restored drug-induced loss in viability of treated cells for up to 72 hours. This antagonism of microtubule-targeting drugs was accompanied by a delay in cell cycle progression and inhibition of the buildup of cyclin-B1 at the microtubule organizing center of treated cells. However, quercetin did not inhibit the microtubule targeting of taxol or nocodazole. Despite the short-term protection of cells by quercetin, colony formation and clonogenicity of HCT116 cells were still suppressed by quercetin or quercetin-taxol combination. The status of cell adherence to growth matrix was critical in determining the sensitivity of HCT116 cells to quercetin. We conclude that while long-term exposure of cancer cells to quercetin may prevent cell proliferation and survival, the interference of quercetin with cell cycle progression diminishes the efficacy of microtubule-targeting drugs to arrest cells at G2/M. PMID:21058190

  12. Potential biomarkers for paclitaxel sensitivity in hypopharynx cancer cell

    PubMed Central

    Xu, Cheng-Zhi; Shi, Run-Jie; Chen, Dong; Sun, Yi-Yuan; Wu, Qing-Wei; Wang, Tao; Wang, Pei-Hua

    2013-01-01

    Paclitaxel has been proved to be active in treatment and larynx preservation of HNSCC, however, the fact that about 20-40% patients do not respond to paclitaxel makes it urgent to figure out the biomarkers for paclitaxel-based treatment in Hypopharynx cancer (HPC) patients to improve the therapy effect. In this work, Fadu cells, treated or untreated with low dose of paclitaxel for 24 h, were applied to DNA microarray chips. The differential expression in mRNAs and miRs was analyzed and the network between expression-altered mRNAs and miRs was constructed. Differentially expressed genes were mainly enriched in superpathway of cholesterol biosynthesis (ACAT2, MSMO1, LSS, FDFT1 and FDPS etc.), complement system (C3, C1R, C1S, CFR and CFB etc.), interferon signaling (IFIT1, IFIT3, IFITM1 and MX1 etc.), mTOR signaling (MRAS, PRKAA2, PLD1, RND3 and EIF4A1 etc.) and IGF1 signaling (MRAS, IGFBP7, JUN and FOS etc.), most of these pathways are implicated in tumorigenesis or chemotherapy resistance. The first three pathways were predicted to be suppressed, while the last two pathways were predicted to be induced by paclitaxel, suggesting the combination therapy with mTOR inhibition and paclitaxel might be better than single one. The dramatically expression-altered miRs were miR-112, miR-7, miR-1304, miR-222*, miR-29b-1* (these five miRs were upregulated) and miR-210 (downregulated). The 26 putative target genes mediated by the 6 miRs were figured out and the miR-gene network was constructed. Furthermore, immunoblotting assay showed that ERK signaling in Fadu cells was active by low dose of paclitaxel but repressed by high dose of paclitaxel. Collectively, our data would provide potential biomarkers and therapeutic targets for paclitaxel-based therapy in HPC patients. PMID:24294361

  13. Paclitaxel delivery to brain tumors from hydrogels: a computational study.

    PubMed

    Torres, Alexis J; Zhu, Charles; Shuler, Michael L; Pannullo, Susan

    2011-01-01

    Malignant gliomas are aggressive forms of primary brain tumors characterized by a poor prognosis. The most successful treatment so far is the local implantation of polymer carriers (Gliadel® wafers) for the sustained release of carmustine. To improve the effectiveness of local drug treatment, new polymer carriers and pharmacological agents are currently being investigated. Of particular interest is a set of novel thermo-gelling polymers for the controlled release of hydrophobic drugs such as paclitaxel (e.g., OncoGel™). Herein, we use computational mass transport simulations to investigate the effectiveness of paclitaxel delivery from hydrogel-forming polymer carriers. We found similar (within 1-2 mm) therapeutic penetration distances of paclitaxel when released from these hydrogels as compared with carmustine released from Gliadel® wafers. Effective therapeutic concentrations were maintained for >30 days for paclitaxel when released from the hydrogel as compared with 4 days for carmustine released from Gliadel® wafers. Convection in brain tissue prevented the formation of a uniform drug concentration gradient around the implant. In addition, the surface area to volume ratio of the gel is an important factor that should be considered to maintain a controlled release of paclitaxel within the degradation lifetime of the polymer matrix. PMID:21786432

  14. The preparation, characterization, and pharmacokinetic studies of chitosan nanoparticles loaded with paclitaxel/dimethyl-β-cyclodextrin inclusion complexes

    PubMed Central

    Ye, Ya-Jing; Wang, Yun; Lou, Kai-Yan; Chen, Yan-Zuo; Chen, Rongjun; Gao, Feng

    2015-01-01

    A novel biocompatible and biodegradable drug-delivery nanoparticle (NP) has been developed to minimize the severe side effects of the poorly water-soluble anticancer drug paclitaxel (PTX) for clinical use. PTX was loaded into the hydrophobic cavity of a hydrophilic cyclodextrin derivative, heptakis (2,6-di-O-methyl)-β-cyclodextrin (DM-β-CD), using an aqueous solution-stirring method followed by lyophilization. The resulting PTX/DM-β-CD inclusion complex dramatically enhanced the solubility of PTX in water and was directly incorporated into chitosan (CS) to form NPs (with a size of 323.9–407.8 nm in diameter) using an ionic gelation method. The formed NPs had a zeta potential of +15.9–23.3 mV and showed high colloidal stability. With the same weight ratio of PTX to CS of 0.7, the loading efficiency of the PTX/DM-β-CD inclusion complex-loaded CS NPs was 30.3-fold higher than that of the PTX-loaded CS NPs. Moreover, it is notable that PTX was released from the DM-β-CD/CS NPs in a sustained-release manner. The pharmacokinetic studies revealed that, compared with reference formulation (Taxol®), the PTX/DM-β-CD inclusion complex-loaded CS NPs exhibited a significant increase in AUC0→24h (the area under the plasma drug concentration–time curve over the period of 24 hours) and mean residence time by 2.7-fold and 1.4-fold, respectively. Therefore, the novel drug/DM-β-CD inclusion complex-loaded CS NPs have promising applications for the significantly improved delivery and controlled release of the poorly water-soluble drug PTX or its derivatives, thus possibly leading to enhanced therapeutic efficacy and less severe side effects. PMID:26170666

  15. Design and Characterization of PEG-Derivatized Vitamin E as a Nanomicellar Formulation for Delivery of Paclitaxel

    PubMed Central

    Lu, Jianqin; Huang, Yixian; Zhao, Wenchen; Chen, Yichao; Li, Jiang; Gao, Xiang; Venkataramanan, Raman; Li, Song

    2013-01-01

    Various PEG-Vitamin E conjugates including D-alpha-tocopheryl polyethylene glycol succinate 1000 (TPGS) have been extensively studied as a nonionic surfactant in various drug delivery systems. However, limited information is available about the structure-activity relationship of PEG-Vitamin E conjugates as a micellar formulation for paclitaxel (PTX). In this study, four PEG-Vitamin E conjugates were developed that vary in the molecular weight of PEG (PEG2K vs PEG5K) and the molar ratio of PEG/Vitamin E (1/1 vs 1/2) in the conjugates. These conjugates were systematically characterized with respect to CMC, PTX loading efficiency, stability, and their efficiency in delivery of PTX to tumor cells in vitro and in vivo. Our data show that PEG5K-conjugates have lower CMC values and are more effective in PTX loading with respect to both loading capacity and stability. The conjugates with two Vitamin E molecules also worked better than the conjugates with one molecule of Vitamin E, particularly for PEG2K-system. Furthermore, all of the PEG-Vitamin E conjugates can inhibit P-gp function with their activity being comparable to that of TPGS. More importantly, PTX-loaded PEG5K-VE2 resulted in significantly improved tumor growth inhibitory effect in comparison to PTX formulated in PEG2K-VE or PEG2K-VE2, as well as Cremophor EL (Taxol) in a syngeneic mouse model of breast cancer (4T1.2). Our study suggests that PEG5K-Vitmin E2 may hold promise as an improved micellar formulation for in vivo delivery of anticancer agents such as PTX. PMID:23768151

  16. A toxic organic solvent-free technology for the preparation of PEGylated paclitaxel nanosuspension based on human serum albumin for effective cancer therapy

    PubMed Central

    Yin, Tingjie; Dong, Lihui; Cui, Bei; Wang, Lei; Yin, Lifang; Zhou, Jianping; Huo, Meirong

    2015-01-01

    Clinically, paclitaxel (PTX) is one of most commonly prescribed therapies against a wide range of solid neoplasms. Despite its success, the clinical applicability of PTX (Taxol®) is severely hampered by systemic toxicities induced by Cremophor EL. While attempts to bypass the need for Cremophor EL have been developed through platforms such as Abraxane™, nab™ relies heavily on the use of organic solvents, namely, chloroform. The toxicity introduced by residual chloroform poses a potential risk to patient health. To mitigate the toxicities of toxic organic solvent-based manufacture methods, we have designed a method for the formulation of PTX nanosuspensions (PTX-PEG [polyethylene glycol]-HSA [human serum albumin]) that eliminates the dependence on toxic organic solvents. Coined the solid-dispersion technology, this technique permits the dispersion of PTX into PEG skeleton without the use of organic solvents or Cremophor EL as a solubilizer. Once the PTX-PEG dispersion is complete, the dispersion can be formulated with HSA into nanosuspensions suitable for intravenous administration. Additionally, the incorporation of PEG permits the prolonged circulation through the steric stabilization effect. Finally, HSA-mediated targeting permits active receptor-mediated endocytosis for enhanced tumor uptake and reduced side effects. By eliminating the need for both Cremophor EL and organic solvents while simultaneously increasing antitumor efficacy, this method provides a superior alternative to currently accepted methods for PTX delivery. PMID:26715846

  17. Enhanced antitumor efficacy by d-glucosamine-functionalized and paclitaxel-loaded poly(ethylene glycol)-co-poly(trimethylene carbonate) polymer nanoparticles.

    PubMed

    Jiang, Xinyi; Xin, Hongliang; Gu, Jijin; Du, Fengyi; Feng, Chunlai; Xie, Yike; Fang, Xiaoling

    2014-05-01

    The poor selectivity of chemotherapeutics for cancer treatment may lead to dose-limiting side effects that compromise clinical outcomes. To solve the problem, surface-functionalized polymer nanoparticles are regarded as promising tumor-targeting delivery system. On the basis of glucose transporter (GLUT) overexpression on cancer cells, d-glucosamine-conjugated and paclitaxel-loaded poly(ethylene glycol)-co-poly(trimethylene carbonate) copolymer nanoparticles (DGlu-NP/PTX) were developed as potential tumor-targeting drug delivery system in this study. Because of the high affinity between d-glucosamine and GLUT, DGlu-NP/PTX could target to tumor tissue through GLUT-mediated endocytosis to improve the selectivity of PTX. DGlu-NP/PTX was prepared by emulsion/solvent evaporation technique and characterized in terms of morphology, size, and zeta potential. In vitro evaluation of two-dimensional cells and three-dimensional tumor spheroids revealed that DGlu-NP/PTX was more potent than those of plain nanoparticles (NP/PTX) and Taxol. In vivo multispectral fluorescent imaging indicated that DGlu-NP had higher specificity and efficiency on subcutaneous xenografts tumor of mouse. Furthermore, DGlu-NP/PTX showed the greatest tumor growth inhibitory effect on in vivo subcutaneous xenografts model with no evident toxicity. Therefore, these results demonstrated that DGlu-NP/PTX could be used as potential vehicle for cancer treatment. PMID:24619482

  18. Intraperitoneal delivery of paclitaxel by poly(ether-anhydride) microspheres effectively suppresses tumor growth in a murine metastatic ovarian cancer model

    PubMed Central

    Yang, Ming; Yu, Tao; Wood, Joseph; Wang, Ying-Ying; Tang, Benjamin C.; Zeng, Qi; Simons, Brian W.; Fu, Jie; Chuang, Chi-Mu; Lai, Samuel K.; Wu, T.-C.; Hung, Chien-Fu; Hanes, Justin

    2014-01-01

    Intraperitoneal (IP) chemotherapy is more effective than systemic chemotherapy for treating advanced ovarian cancer, but is typically associated with severe complications due to high dose, frequent administration schedule, and use of non-biocompatible excipients/delivery vehicles. Here, we developed paclitaxel (PTX)-loaded microspheres composed of di-block copolymers of poly(ethylene glycol) and poly(sebacic acid) (PEG-PSA) for safe and sustained IP chemotherapy. PEG-PSA microspheres provided efficient loading (~ 13% w/w) and prolonged release (~ 13 days) of PTX. In a murine ovarian cancer model, a single dose of IP PTX/PEG-PSA particles effectively suppressed tumor growth for more than 40 days and extended the median survival time to 75 days compared to treatments with Taxol® (47 days) or IP placebo particles (34 days). IP PTX/PEG-PSA was well tolerated, with only minimal to mild inflammation. Our findings support PTX/PEG–PSA microspheres as a promising drug delivery platform for IP therapy of ovarian cancer, and potentially other metastatic peritoneal cancers. PMID:24816829

  19. Intraperitoneal delivery of paclitaxel by poly(ether-anhydride) microspheres effectively suppresses tumor growth in a murine metastatic ovarian cancer model.

    PubMed

    Yang, Ming; Yu, Tao; Wood, Joseph; Wang, Ying-Ying; Tang, Benjamin C; Zeng, Qi; Simons, Brian W; Fu, Jie; Chuang, Chi-Mu; Lai, Samuel K; Wu, T-C; Hung, Chien-Fu; Hanes, Justin

    2014-04-01

    Intraperitoneal (IP) chemotherapy is more effective than systemic chemotherapy for treating advanced ovarian cancer, but is typically associated with severe complications due to high dose, frequent administration schedule, and use of non-biocompatible excipients/delivery vehicles. Here, we developed paclitaxel (PTX)-loaded microspheres composed of di-block copolymers of poly(ethylene glycol) and poly(sebacic acid) (PEG-PSA) for safe and sustained IP chemotherapy. PEG-PSA microspheres provided efficient loading (~ 13% w/w) and prolonged release (~ 13 days) of PTX. In a murine ovarian cancer model, a single dose of IP PTX/PEG-PSA particles effectively suppressed tumor growth for more than 40 days and extended the median survival time to 75 days compared to treatments with Taxol(®) (47 days) or IP placebo particles (34 days). IP PTX/PEG-PSA was well tolerated, with only minimal to mild inflammation. Our findings support PTX/PEG-PSA microspheres as a promising drug delivery platform for IP therapy of ovarian cancer, and potentially other metastatic peritoneal cancers. PMID:24816829

  20. Paclitaxel-loaded poly(glycolide-co-ε-caprolactone)-b-D-α-tocopheryl polyethylene glycol 2000 succinate nanoparticles for lung cancer therapy

    PubMed Central

    Zhao, Tiejun; Chen, Hezhong; Dong, Yuchao; Zhang, Jiajun; Huang, Haidong; Zhu, Ji; Zhang, Wei

    2013-01-01

    In order to improve the therapeutic efficacy and minimize the side effects of lung cancer chemotherapy, the formulation of paclitaxel-loaded poly(glycolide-co-ε-caprolactone)-b-D-α-tocopheryl polyethylene glycol 2000 succinate nanoparticles (PTX-loaded [PGA-co-PCL]-b-TPGS2k NPs) was prepared. The novel amphiphilic copolymer (PGA-co-PCL)-b-TPGS2k was synthesized by ring-opening polymerization and characterized by proton nuclear magnetic resonance spectroscopy and gel permeation chromatography. The PTX-loaded (PGA-co-PCL)-b-TPGS2k NPs were characterized in terms of size, size distribution, zeta potential, drug encapsulation, surface morphology, and drug release. In vitro cellular uptakes of NPs were investigated with confocal laser scanning microscopy, indicating the coumarin 6-loaded (PGA-co-PCL)-b-TPGS2k NPs could be internalized by human lung cancer A-549 cells. The antitumor effect of PTX-loaded NPs was evaluated, both in vitro and in vivo, on an A-549 cell tumor-bearing mouse model via intratumoral injection. The commercial PTX formulation Taxol was chosen as the reference. Experimental results showed that the PTX-loaded NPs possessed higher cytotoxicity and could effectively inhibit the growth of tumor. All the results suggested that amphiphilic copolymer (PGA-co-PCL)-b-TPGS2k could act as a potential biological material for nanoformulation in the treatment of lung cancer. PMID:23696703

  1. Controlled Release, Intestinal Transport, and Oral Bioavailablity of Paclitaxel Can be Considerably Increased Using Suitably Tailored Pegylated Poly(Anhydride) Nanoparticles.

    PubMed

    Calleja, Patricia; Espuelas, Socorro; Vauthier, Christine; Ponchel, Gilles; Irache, Juan M

    2015-09-01

    The aim of the work was to evaluate in vitro and in vivo the effect of the addition of poly(ethylene glycol) (PEG) to paclitaxel (PTX)-cyclodextrin poly(anhydride) nanoparticles. For this, PTX in poly(anhydride) nanoparticles complexed with cyclodextrins (either 2-hydroxypropyl-β-cyclodextrin or β-cyclodextrin) and combined with PEG 2000 were prepared by the solvent displacement method. Intestinal permeability in vitro and in vivo pharmacokinetic studies in C57BL/6J mice were performed. Nanoparticle formulations containing PTX increased its apparent permeability through rat intestine in vitro in the Ussing chambers, enhancing its permeability 10-15 times compared with commercial Taxol®. In addition, in pharmacokinetic studies, drug plasma levels were observed for at least 24 h leading to a relative oral bioavailability between 60% and 80% for PTX complexed with cyclodextrin and loaded in pegylated poly(anhydride) nanoparticles after oral gavage. In all, PTX-cyclodextrin complexes encapsulated in pegylated nanoparticles managed to promote the intestinal uptake of the drug displaying sustained plasma levels after oral administration to laboratory animals with a more prolonged plasma profile compared with the formulation with no PEG at all. Therefore, pegylated poly(anhydride) nanoparticles represent a promising carrier for the oral delivery of PTX. PMID:25600579

  2. Nab-paclitaxel in patients with metastatic melanoma.

    PubMed

    Leon-Ferre, Roberto A; Markovic, Svetomir N

    2015-12-01

    Cutaneous melanoma is one of the most aggressive and resistant malignancies in humans. Until recently, progress in the treatment of metastatic melanoma remained dormant for nearly two decades. However, recent advances in immune and targeted therapeutic approaches have led to dramatic and paradigm-shifting advances in the management of metastatic melanoma, that are now leading the way for other malignancies. With the advent of these new therapeutic options, chemotherapy is no longer favored as a first line strategy in metastatic melanoma, but continues to play a role in the salvage treatment of patients that have become refractory to immune-based or targeted therapies. Nab-paclitaxel, a solvent-free alternative to solvent-based paclitaxel, has shown in several trials to be active in metastatic melanoma. Herein, we summarize the role of nab-paclitaxel in the management of patients with advanced melanoma. PMID:26536477

  3. Paclitaxel Enhances Carboplatin-DNA Adduct Formation and Cytotoxicity

    PubMed Central

    Jiang, Shuai; Pan, Amy W.; Lin, Tzu-yin; Zhang, Hongyong; Malfatti, Michael; Turteltaub, Kenneth; Henderson, Paul T.; Pan, Chong-xian

    2016-01-01

    This rapid report focuses on the pharmacodynamic mechanism of the carboplatin/paclitaxel combination and correlates it with its cytotoxicity. Consistent with the synergistic to additive antitumor activity (the combination index ranging from 0.53 to 0.94), cells exposed to this combination had significantly increased carboplatin-DNA adduct formation when compared to that of carboplatin alone (450 ± 30 versus 320 ± 120 adducts per 108 nucleotides at 2 h, p = 0.004). Removal of paclitaxel increased the repair of carboplatin-DNA adducts: 39.4 versus 33.1 adducts per 108 nucleotides per hour in carboplatin alone (p = 0.021). This rapid report provides the first pharmacodynamics data to support the use of carboplatin/paclitaxel combination in the clinic. PMID:26544157

  4. Combination paclitaxel (1-hour) and carboplatin (AUC 7.5) in advanced non-small cell lung cancer: a phase II study by the Fox Chase Cancer Center Network.

    PubMed

    Langer, C J; Millenson, M; O'Dwyer, P; Kosierowski, R; Alexander, R; Litwin, S; McAleer, C A; Bonjo, C A; Ozols, R

    1996-12-01

    We have previously reported a 62% response rate and 54% 1-year survival rate for patients with advanced non-small cell lung cancer (NSCLC) treated with paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) by 24-hour infusion in combination with carboplatin, using area under the concentration-time curve dosing (FCCC 93-024). Myelosuppression proved dose limiting, but was substantially reduced by the routine use of granulocyte colony-stimulating factor during the second and subsequent cycles. Antitumor activity has been reported with minimal myelosuppression, with paclitaxel 135 and 200 mg/m2 given every 3 weeks by 1-hour infusion to patients with NSCLC. In November 1994, we initiated a phase II trial of paclitaxel 175 mg/m2 given over 1 hour, with carboplatin dosed to a fixed, targeted area under the concentration-time curve of 7.5 every 3 weeks. In the absence of grade 4 myelosuppression, paclitaxel was escalated on an intrapatient basis by 35 mg/m2 per cycle to a maximum dose of 280 mg/m2 by cycle 4. Granulocyte colony-stimulating factor was not routinely used. Eligibility stipulated advanced, measurable, chemotherapy-naive NSCLC. Of 47 patients accrued, 39 (83%) had Eastern Cooperative Oncology Group performance status 1. The median age was 64 years; 40 patients were evaluable for toxicity. Of the first 20 evaluable patients accrued (cohort A), myelosuppression was tolerable. Cumulative peripheral sensory neuropathy grade > or = 1 in 15 (75%) patients and grade 3 in six (30%), however, generally occurring at paclitaxel doses greater than 215 mg/m2, obligated removal from study of at least three patients, despite the absence of disease progression, and proved to be dose-limiting. Consequently, the protocol was revised: the starting dose of paclitaxel was reduced to 135 mg/m2, with intrapatient dose escalation of 40 mg/m2 per cycle to a maximum dose of 215 mg/m2, thus recapitulating the original dosing schema used in FCCC 93-024. To date, 25 patients have been enrolled in this second cohort (cohort B) and treatment has been better tolerated. Of 21 evaluable patients, 13 (62%) have experienced peripheral sensory neuropathy, but only one (5%) has been grade 3. Myelosuppression also has been less pronounced, with 33% grade 4 granulocytopenia and 13% grade > or = 3 thrombocytopenia in cohort B compared with 70% and 50%, respectively, in cohort A. Of the first 22 patients accrued to cohort A, 12 (55%) had major objective responses. Median event-free survival is 23 weeks and median survival is 47 weeks. Of 15 evaluable patients in cohort B, five (33%) have had major objective responses. It is too early to report survival data. In conclusion, paclitaxel by 1-hour infusion in combination with carboplatin at a fixed targeted area under the concentration-time curve of 7.5 is an active regimen in advanced NSCLC. Neurotoxicity, rather than myelosuppression, is dose and protocol limiting at paclitaxel doses exceeding 215 mg/m2. PMID:9007119

  5. Covalent linkage of nanodiamond-paclitaxel for drug delivery and cancer therapy

    NASA Astrophysics Data System (ADS)

    Liu, Kuang-Kai; Zheng, Wen-Wei; Wang, Chi-Ching; Chiu, Yu-Chung; Cheng, Chia-Liang; Lo, Yu-Shiu; Chen, Chinpiao; Chao, Jui-I.

    2010-08-01

    A nanoparticle-conjugated cancer drug provides a novel strategy for cancer therapy. In this study, we manipulated nanodiamond (ND), a carbon nanomaterial, to covalently link paclitaxel for cancer drug delivery and therapy. Paclitaxel was bound to the surface of 3-5 nm sized ND through a succession of chemical modifications. The ND-paclitaxel conjugation was measured by atomic force microscope and nuclear magnetic resonance spectroscopy, and confirmed with infrared spectroscopy by the detection of deuterated paclitaxel. Treatment with 0.1-50 µg ml - 1 ND-paclitaxel for 48 h significantly reduced the cell viability in the A549 human lung carcinoma cells. ND-paclitaxel induced both mitotic arrest and apoptosis in A549 cells. However, ND alone or denatured ND-paclitaxel (after treatment with strong alkaline solution, 1 M NaOH) did not induce the damage effects on A549 cells. ND-paclitaxel was taken into lung cancer cells in a concentration-dependent manner using flow cytometer analysis. The ND-paclitaxel particles were located in the microtubules and cytoplasm of A549 cells observed by confocal microscopy. Furthermore, ND-paclitaxel markedly blocked the tumor growth and formation of lung cancer cells in xenograft SCID mice. Together, we provide a functional covalent conjugation of ND-paclitaxel, which can be delivered into lung carcinoma cells and preserves the anticancer activities on the induction of mitotic blockage, apoptosis and anti-tumorigenesis.

  6. Albumin-bound paclitaxel in solid tumors: clinical development and future directions

    PubMed Central

    Kundranda, Madappa N; Niu, Jiaxin

    2015-01-01

    Albumin-bound paclitaxel (nab-paclitaxel) is a solvent-free formulation of paclitaxel that was initially developed more than a decade ago to overcome toxicities associated with the solvents used in the formulation of standard paclitaxel and to potentially improve efficacy. Nab-paclitaxel has demonstrated an advantage over solvent-based paclitaxel by being able to deliver a higher dose of paclitaxel to tumors and decrease the incidence of serious toxicities, including severe allergic reactions. To date, nab-paclitaxel has been indicated for the treatment of three solid tumors in the USA. It was first approved for the treatment of metastatic breast cancer in 2005, followed by locally advanced or metastatic non-small-cell lung cancer in 2012, and most recently for metastatic pancreatic cancer in 2013. Nab-paclitaxel is also under investigation for the treatment of a number of other solid tumors. This review highlights key clinical efficacy and safety outcomes of nab-paclitaxel in the solid tumors for which it is currently indicated, discusses ongoing trials that may provide new data for the expansion of nab-paclitaxel’s indications into other solid tumors, and provides a clinical perspective on the use of nab-paclitaxel in practice. PMID:26244011

  7. Enabling Anticancer Therapeutics by Nanoparticle Carriers: The Delivery of Paclitaxel

    PubMed Central

    Liu, Yongjin; Zhang, Bin; Yan, Bing

    2011-01-01

    Anticancer drugs, such as paclitaxel (PTX), are indispensable for the treatment of a variety of malignancies. However, the application of most drugs is greatly limited by the low water solubility, poor permeability, or high efflux from cells. Nanoparticles have been widely investigated to enable drug delivery due to their low toxicity, sustained drug release, molecular targeting, and additional therapeutic and imaging functions. This review takes paclitaxel as an example and compares different nanoparticle-based delivery systems for their effectiveness in cancer chemotherapy. PMID:21845085

  8. Enabling anticancer therapeutics by nanoparticle carriers: the delivery of Paclitaxel.

    PubMed

    Liu, Yongjin; Zhang, Bin; Yan, Bing

    2011-01-01

    Anticancer drugs, such as paclitaxel (PTX), are indispensable for the treatment of a variety of malignancies. However, the application of most drugs is greatly limited by the low water solubility, poor permeability, or high efflux from cells. Nanoparticles have been widely investigated to enable drug delivery due to their low toxicity, sustained drug release, molecular targeting, and additional therapeutic and imaging functions. This review takes paclitaxel as an example and compares different nanoparticle-based delivery systems for their effectiveness in cancer chemotherapy. PMID:21845085

  9. Preclinical evaluation of nanoparticle albumin-bound paclitaxel for treatment of pediatric bone sarcoma.

    PubMed

    Wagner, Lars M; Yin, Hong; Eaves, David; Currier, Mark; Cripe, Timothy P

    2014-11-01

    The combination of docetaxel and gemcitabine is frequently used to treat recurrent bone sarcoma. Nanoparticle albumin-bound paclitaxel (nab-paclitaxel) is less toxic and more active than docetaxel or paclitaxel for breast cancer patients. The combination of nab-paclitaxel and gemcitabine has preclinical synergy and is approved to treat pancreatic cancer. We observed growth inhibition and improved survival with nab-paclitaxel in a Ewing sarcoma xenograft, and activity was additive with gemcitabine in an osteosarcoma model. Primary Ewing sarcoma tumors expressed the transport protein SPARC, previously associated with nab-paclitaxel activity. These findings provide rationale for further evaluation of nab-paclitaxel with gemcitabine for bone sarcoma. PMID:24753077

  10. Expression of immediate early genes after treatment of human astrocytoma cells with radiation and taxol

    SciTech Connect

    Gubits, R.M.; Geard, C.R.; Schiff, P.B.

    1993-10-20

    The promising chemotherapeutic agent, taxol, has been shown to sensitize the G18 line of human astrocytoma cells to ionizing radiation. The present studies were performed to identify specific changes in gene expression associated with this altered sensitivity. The products of immediate early genes, which are induced transiently in cells in response to a variety of treatments, including growth factors, neurotransmitters, and irradiation with UV light or X rays, are thought to initiate a cascade of genetic responses to alterations in cellular environment. The present results demonstrate a dramatic attenuation in one immediate early gene response in association with a treatment that enhances radiosensitivity in a refractory human brain tumor line. 22 refs., 5 figs., 1 tab.

  11. Weekly Paclitaxel Versus Three-Weekly Paclitaxel in Recurrent Platinum-Resistant Epithelial Ovarian and Peritoneal Cancers: A Phase III Study

    PubMed Central

    Osman, Mohammed A.; Elkady, Mohammad S.; Nasr, Khalid E.

    2016-01-01

    INTRODUCTION Treatment of recurrent platinum-resistant ovarian and peritoneal cancers represents a therapeutic challenge. The aim of this Phase III prospective study was to compare the survival benefits, objective response rate, and toxicities among patients treated by weekly paclitaxel with those who underwent three-weekly paclitaxel in recurrent platinum-resistant ovarian and peritoneal cancers. METHOD Patients with recurrent platinum-resistant ovarian and peritoneal cancer were allocated to receive either weekly paclitaxel (arm 1) at 80 m/m2 or three-weekly paclitaxel (arm 2) at 175 mg/m2. RESULTS Fifty-five patients were enrolled (30 arm 1, 25 arm 2). The mean age was 56.7 years, and the median performance status was 0 (Eastern Cooperative Oncology Group [ECOG]). For arms 1 and 2, the objective response rates were 27% and 16%, the median progression-free survival were 7 and 4.5 months, and the median overall survival were 15.5 and 12.5 months, respectively. Treatments also significantly improved the quality of life. Treatment was associated with mild toxicities, and while neuropathy was slightly higher for weekly paclitaxel over three-weekly paclitaxel, hematological toxicities were significantly lower for the former than the latter. CONCLUSION Paclitaxel rechallenge showed antitumor activity in recurrent platinum-resistant ovarian and peritoneal cancers. Weekly paclitaxel achieved better results than three-weekly paclitaxel in terms of survival benefits, quality of life, and toxicities. PMID:27147900

  12. Kinetics of taxol production and nutrient use in suspension cultures of Taxus cuspidata in shake flasks and a Wilson-type bioreactor.

    PubMed

    Pestchanker, L J; Roberts, S C; Shuler, M L

    1996-09-01

    Suspension cultures of Taxus cuspidata were grown in shake flasks and Wilson-type reactors where bubbled air provided both agitation and mixing. Taxol titers of 22 mg l-1 were achieved for both configurations in 20 days for a volumetric productivity of 1.1 mg l-1 day-1. This productivity is many-fold higher than reported for other Taxus sp. suspension cultures. Taxol was released to the extracellular medium as it was produced with little intracellular retention (< or = 10%). Taxol production occurred during the last seven days of the cultivation period and was not growth-associated. Although the same taxol titers could be obtained in both reactor types, nutrient uptake rates were faster in the Wilson-type reactor than in shake flasks. Formation of a growth ring in the Wilson-type reactor reduced measured cell mass yields. PMID:8987485

  13. SPARC independent drug delivery and antitumour effects of nab-paclitaxel in genetically engineered mice

    PubMed Central

    Neesse, Albrecht; Frese, Kristopher K; Chan, Derek S; Bapiro, Tashinga E; Howat, William J; Richards, Frances M; Ellenrieder, Volker; Jodrell, Duncan I; Tuveson, David A

    2014-01-01

    Design Pharmacokinetic and pharmacodynamic parameters of cremophor-paclitaxel, nab-paclitaxel (human-albumin-bound paclitaxel, Abraxane) and a novel mouse-albumin-bound paclitaxel (m-nab-paclitaxel) were evaluated in genetically engineered mouse models (GEMMs) by liquid chromatography-tandem mass spectrometry (LC-MS/MS), histological and biochemical analysis. Preclinical evaluation of m-nab-paclitaxel included assessment by three-dimensional high-resolution ultrasound and molecular analysis in a novel secreted protein acidic and rich in cysteine (SPARC)-deficient GEMM of pancreatic ductal adenocarcinoma (PDA). Results nab-Paclitaxel exerted its antitumoural effects in a dose-dependent manner and was associated with less toxicity compared with cremophor-paclitaxel. SPARC nullizygosity in a GEMM of PDA, KrasG12D;p53flox/−;p48Cre (KPfC), resulted in desmoplastic ductal pancreas tumours with impaired collagen maturation. Paclitaxel concentrations were significantly decreased in SPARC null plasma samples and tissues when administered as low-dose m-nab-paclitaxel. At the maximally tolerated dose, SPARC deficiency did not affect the intratumoural paclitaxel concentration, stromal deposition and the immediate therapeutic response. Conclusions nab-Paclitaxel accumulates and acts in a dose-dependent manner. The interaction of plasma SPARC and albumin-bound drugs is observed at low doses of nab-paclitaxel but is saturated at therapeutic doses in murine tumours. Thus, this study provides important information for future preclinical and clinical trials in PDA using nab-paclitaxel in combination with novel experimental and targeted agents. PMID:24067278

  14. Functionalized nanospheres for targeted delivery of paclitaxel.

    PubMed

    Bushman, Jared; Vaughan, Asa; Sheihet, Larisa; Zhang, Zheng; Costache, Marius; Kohn, Joachim

    2013-11-10

    Targeted delivery of anti-cancer agents to cancer cells is a mature line of investigation that has yet to realize its full potential. In this study we report on the development of a delivery platform with the future goal of merging two thus far parallel methods for selective elimination of cancer cells: targeted nanospheres and pretargeted radioimmunotherapy. Several clinical trials have shown the promise of pretargeted radioimmunotherapy, which leverages the specificity of antibodies for targeted cell populations and delivers a localized dose of a biotinylated radionuclide that is most often administered following binding of a biotinylated antibody and streptavidin (StA) to the target cells. The work presented here describes the development of biotinylated nanospheres based on an ABA-type copolymer comprised of a tyrosine-derived oligomer as the B-block and poly(ethylene glycol) (PEG) A-blocks. The biotinylated nanospheres encapsulate paclitaxel (PTX) to the same extent as unbiotinylated nanospheres. Efficacy of targeting was shown on CD44 positive cells in the SUM159 breast cancer cell line by incubating the cells sequentially with a biotinylated anti-CD44 antibody, StA and the biotinylated nanospheres encapsulating PTX. Targeted nanospheres achieved the half maximal inhibitory concentration of PTX on SUM159 cells at a 5-10 fold lower concentration than that of PTX applied in either non-targeted nanospheres or free drug approaches. Moreover, targeted nanospheres selectively eliminated CD44 positive SUM159 cells compared to free PTX and untargeted nanospheres. This new generation of nano-sized carrier offers a versatile platform that can be adopted for a wide variety of drug and target specific applications and has the potential to be combined with the clinically emerging method of pretargeted radioimmunotherapy. PMID:23792807

  15. Relationship between the structure of taxol and other taxanes on induction of tumor necrosis factor-alpha gene expression and cytotoxicity.

    PubMed

    Burkhart, C A; Berman, J W; Swindell, C S; Horwitz, S B

    1994-11-15

    Taxol is an antitumor drug with cytotoxic properties that correlate with its microtubule-stabilizing activities. It has been reported that taxol parallels lipopolysaccharide in its effects on the induction of tumor necrosis factor-alpha (TNF-alpha) gene expression in macrophages (C. Bogdan and A. Ding, J. Leukocyte Biol., 52: 119-121, 1992; C. L. Manthey, M. E. Brandes, P. Y. Perera, and S. Vogel, J. Immunol., 149: 2459-2465, 1992; J. M. Carboni, C. Singh, and M. A. Tepper, Natl. Cancer Inst. Monogr., 15: 95-101, 1993). Structure-activity studies using taxol and related taxanes have been done to determine the relationship between the effects of taxol on TNF-alpha gene expression and its cytotoxic and microtubule-stabilizing activities. Using Northern blot analysis, it was found that changes in the structure of taxol that did not alter cytotoxicity did prevent the induction of TNF-alpha gene expression. The data presented in this paper demonstrate that the effects of taxol on TNF-alpha gene expression are distinct from its known cytotoxic properties. PMID:7954398

  16. Sunitinib Plus Paclitaxel Versus Bevacizumab Plus Paclitaxel for First-Line Treatment of Patients With Advanced Breast Cancer: A Phase III, Randomized, Open-Label Trial

    PubMed Central

    Robert, Nicholas J.; Saleh, Mansoor N.; Paul, Devchand; Generali, Daniele; Gressot, Laurent; Copur, Mehmet S.; Brufsky, Adam M.; Minton, Susan E.; Giguere, Jeffrey K.; Smith, John W.; Richards, Paul D.; Gernhardt, Diana; Huang, Xin; Liau, Katherine F.; Kern, Kenneth A.; Davis, John

    2015-01-01

    Introduction A multicenter, open-label phase III study was conducted to test whether sunitinib plus paclitaxel prolongs progression-free survival (PFS) compared with bevacizumab plus paclitaxel as first-line treatment for patients with HER2− advanced breast cancer. Patients and Methods Patients with HER2− advanced breast cancer who were disease free for ≥ 12 months after adjuvant taxane treatment were randomized (1:1; planned enrollment 740 patients) to receive intravenous (I.V.) paclitaxel 90 mg/m2 every week for 3 weeks in 4-week cycles plus either sunitinib 25 to 37.5 mg every day or bevacizumab 10 mg/kg I.V. every 2 weeks. Results The trial was terminated early because of futility in reaching the primary endpoint as determined by the independent data monitoring committee during an interim futility analysis. At data cutoff, 242 patients had been randomized to sunitinib-paclitaxel and 243 patients to bevacizumab-paclitaxel. Median PFS was shorter with sunitinib-paclitaxel (7.4 vs. 9.2 months; hazard ratio [HR] 1.63 [95% confidence interval (CI), 1.18–2.25]; 1-sided P = .999). At a median follow-up of 8.1 months, with 79% of sunitinib-paclitaxel and 87% of bevacizumab-paclitaxel patients alive, overall survival analysis favored bevacizumab-paclitaxel (HR 1.82 [95% CI, 1.16–2.86]; 1-sided P = .996). The objective response rate was 32% in both arms, but median duration of response was shorter with sunitinib-paclitaxel (6.3 vs. 14.8 months). Bevacizumab-paclitaxel was better tolerated than sunitinib-paclitaxel. This was primarily due to a high frequency of grade 3/4, treatment-related neutropenia with sunitinib-paclitaxel (52%) precluding delivery of the prescribed doses of both drugs. Conclusion The sunitinib-paclitaxel regimen evaluated in this study was clinically inferior to the bevacizumab-paclitaxel regimen and is not a recommended treatment option for patients with advanced breast cancer. PMID:21569994

  17. Radiosensitization of malignant gliomas following intracranial delivery of paclitaxel biodegradable polymer microspheres

    PubMed Central

    Gabikian, Patrik; Tyler, Betty M.; Zhang, Irma; Li, Khan W.; Brem, Henry; Walter, Kevin A.

    2015-01-01

    Object The aim of this study was to demonstrate that paclitaxel could function as a radiosensitizer for malignant glioma in vitro and in vivo. Methods The radiosensitizing effect of paclitaxel was tested in vitro using the human U373MG and rat 9L glioma cell lines. Cell cycle arrest in response to paclitaxel exposure was quantified by flow cytometry. Cells were subsequently irradiated, and toxicity was measured using the clonogenic assay. In vivo studies were performed in Fischer 344 rats implanted with intracranial 9L gliosarcoma. Rats were treated with control polymer implants, paclitaxel controlled-release polymers, radiotherapy, or a combination of the 2 treatments. The study end point was survival. Results Flow cytometry demonstrated G2-M arrest in both U373MG and 9L cells following 6–12 hours of paclitaxel exposure. The order in which the combination treatment was administered was significant. Exposure to radiation treatment (XRT) during the 6–12 hours after paclitaxel treatment resulted in a synergistic reduction in colony formation. This effect was greater than the effect from either treatment alone and was also greater than the effect of radiation exposure followed by paclitaxel. Rats bearing 9L gliosarcoma tumors treated with paclitaxel polymer administration followed by single-fraction radiotherapy demonstrated a synergistic improvement in survival compared with any other treatment, including radiotherapy followed by paclitaxel treatment. Median survival for control animals was 13 days; for those treated with paclitaxel alone, 21 days; for those treated with XRT alone, 21 days; for those treated with XRT followed by paclitaxel, 45 days; and for those treated with paclitaxel followed by XRT, more than 150 days (p < 0.0001). Conclusions These results indicate that paclitaxel is an effective radiosensitizer for malignant gliomas because it renders glioma cells more sensitive to ionizing radiation by causing G2-M arrest, and induces a synergistic response to chemoradiotherapy. PMID:24605841

  18. Arsenic Trioxide Promotes Paclitaxel Cytotoxicity in Resistant Breast Cancer Cells.

    PubMed

    Bakhshaiesh, Tayebeh Oghabi; Armat, Marzie; Shanehbandi, Dariush; Sharifi, Simin; Baradaran, Behzad; Hejazi, Mohammad Saeed; Samadi, Nasser

    2015-01-01

    A partial response or resistance to chemotherapeutic agents is considered as a main obstacle in treatment of patients with cancer, including breast cancer. Refining taxane-based treatment procedures using adjuvant or combination treatment is a novel strategy to increase the efficiency of chemotherapy. PPM1D is a molecule activated by reactive oxygen species. whose expression is reported to modulate the recruitment of DNA repair molecules. In this study we examined the impact of arsenic trioxide on efficacy of paclitaxel-induced apoptosis in paclitaxel-resistant MCF-7 cells. We also investigated the expression of PPM1D and TP53 genes in response to this combination treatment. Resistant cells were developed from the parent MCF-7 cell line by applying increasing concentrations of paclitaxel. MTT assays were applied to determine the rate of cell survival. DAPI staining using fluorescent microscopy was employed to study apoptotic bodies. Real-time RT-PCR analysis was also applied to determine PPM1D mRNA levels. Our results revealed that combination of arsenic trioxide and paclitaxel elevates the efficacy of the latter in induction of apoptosis in MCF-7/PAC resistant cells. Applying arsenic trioxide also caused significant decreases in PPM1D mRNA levels (p<0.05). Our findings suggest that arsenic trioxide increases paclitaxel-induced apoptosis by down regulation of PPM1D expression. PPM1D dependent signaling can be considered as a novel target to improve the efficacy of chemotherapeutic agents in resistant breast cancer cells. PMID:26225652

  19. Structure-activity relationships of diverse ACGs against multidrug resistant human lung cancer cell line A549/Taxol.

    PubMed

    Yuan, Fei; Bai, Ganggang; Chen, Yong; Miao, Yunjie; Chen, Jianwei; Li, Xiang

    2015-02-15

    Fifteen annonaceous acetogenins (ACGs) with different stereochemical structures and configuration, representing three main classes of bis-adjacent-tetrahydrofuran (THF), bis-nonadjacent-THF, and mono-THF ACGs, were selected to tested for their inhibition activity on A549/Taxol cell line, which is multidrug resistant (MDR). The present study showed that some tested compounds showed significant activity toward A549/Taxol cells, and were more potent than the positive control Verapamil. For example, squamostatin-D (14) (IC50 value=16.19μM) was 7.8 times more active than Verapamil (IC50 value=127.09μM). Those ACGs with more carbons between the THF ring and the γ-unsaturated lactone were more potent. Moreover, ACGs with stereochemical arrangement of erythro were more active than those of threo, the compounds with THF ring configuration of cis seemed to be superior to those of trans. However, if all other structural features were identical, the ACGs with more hydroxyls on the aliphatic chain were not more potent towards A549/Taxol, which was not in accordance with previous studies. Furthermore, bis-nonadjacent-THF ACGs whose molecular weight is 622, with three hydroxyl groups located at carbon 16, 19, 24 and stereochemical arrangement of erythro possibly produced notable cytotoxicity. Based on the above conclusions, we proposed a compound model that may be a promising anti-MDR cancer candidate drug in the future clinical trial. PMID:25582602

  20. Topotecan, pegylated liposomal doxorubicin hydrochloride, paclitaxel, trabectedin and gemcitabine for advanced recurrent or refractory ovarian cancer: a systematic review and economic evaluation.

    PubMed Central

    Edwards, Steven J; Barton, Samantha; Thurgar, Elizabeth; Trevor, Nicola

    2015-01-01

    BACKGROUND Ovarian cancer is the fifth most common cancer in the UK, and the fourth most common cause of cancer death. Of those people successfully treated with first-line chemotherapy, 55-75% will relapse within 2 years. At this time, it is uncertain which chemotherapy regimen is more clinically effective and cost-effective for the treatment of recurrent, advanced ovarian cancer. OBJECTIVES To determine the comparative clinical effectiveness and cost-effectiveness of topotecan (Hycamtin(®), GlaxoSmithKline), pegylated liposomal doxorubicin hydrochloride (PLDH; Caelyx(®), Schering-Plough), paclitaxel (Taxol(®), Bristol-Myers Squibb), trabectedin (Yondelis(®), PharmaMar) and gemcitabine (Gemzar(®), Eli Lilly and Company) for the treatment of advanced, recurrent ovarian cancer. DATA SOURCES Electronic databases (MEDLINE(®), EMBASE, Cochrane Central Register of Controlled Trials, Health Technology Assessment database, NHS Economic Evaluations Database) and trial registries were searched, and company submissions were reviewed. Databases were searched from inception to May 2013. METHODS A systematic review of the clinical and economic literature was carried out following standard methodological principles. Double-blind, randomised, placebo-controlled trials, evaluating topotecan, PLDH, paclitaxel, trabectedin and gemcitabine, and economic evaluations were included. A network meta-analysis (NMA) was carried out. A de novo economic model was developed. RESULTS For most outcomes measuring clinical response, two networks were constructed: one evaluating platinum-based regimens and one evaluating non-platinum-based regimens. In people with platinum-sensitive disease, NMA found statistically significant benefits for PLDH plus platinum, and paclitaxel plus platinum for overall survival (OS) compared with platinum monotherapy. PLDH plus platinum significantly prolonged progression-free survival (PFS) compared with paclitaxel plus platinum. Of the non-platinum-based treatments, PLDH monotherapy and trabectedin plus PLDH were found to significantly increase OS, but not PFS, compared with topotecan monotherapy. In people with platinum-resistant/-refractory (PRR) disease, NMA found no statistically significant differences for any treatment compared with alternative regimens in OS and PFS. Economic modelling indicated that, for people with platinum-sensitive disease and receiving platinum-based therapy, the estimated probabilistic incremental cost-effectiveness ratio [ICER; incremental cost per additional quality-adjusted life-year (QALY)] for paclitaxel plus platinum compared with platinum was £24,539. Gemcitabine plus carboplatin was extendedly dominated, and PLDH plus platinum was strictly dominated. For people with platinum-sensitive disease and receiving non-platinum-based therapy, the probabilistic ICERs associated with PLDH compared with paclitaxel, and trabectedin plus PLDH compared with PLDH, were estimated to be £25,931 and £81,353, respectively. Topotecan was strictly dominated. For people with PRR disease, the probabilistic ICER associated with topotecan compared with PLDH was estimated to be £324,188. Paclitaxel was strictly dominated. LIMITATIONS As platinum- and non-platinum-based treatments were evaluated separately, the comparative clinical effectiveness and cost-effectiveness of these regimens is uncertain in patients with platinum-sensitive disease. CONCLUSIONS For platinum-sensitive disease, it was not possible to compare the clinical effectiveness and cost-effectiveness of platinum-based therapies with non-platinum-based therapies. For people with platinum-sensitive disease and treated with platinum-based therapies, paclitaxel plus platinum could be considered cost-effective compared with platinum at a threshold of £30,000 per additional QALY. For people with platinum-sensitive disease and treated with non-platinum-based therapies, it is unclear whether PLDH would be considered cost-effective compared with paclitaxel at a threshold of £30,000 per additional QALY; trabectedin plus PLDH is unlikely to be considered cost-effective compared with PLDH. For patients with PRR disease, it is unlikely that topotecan would be considered cost-effective compared with PLDH. Randomised controlled trials comparing platinum with non-platinum-based treatments might help to verify the comparative effectiveness of these regimens. STUDY REGISTRATION This study is registered as PROSPERO CRD42013003555. FUNDING The National Institute for Health Research Health Technology Assessment programme. PMID:25626481

  1. Targeted chemotherapy with nanoparticle albumin-bound paclitaxel (nab-paclitaxel) in metastatic breast cancer: which benefit for which patients?

    PubMed Central

    Palumbo, Raffaella; Sottotetti, Federico; Bernardo, Antonio

    2016-01-01

    The therapeutic goals in metastatic breast cancer (MBC) remain palliative in nature, aimed at controlling symptoms, improving or maintaining quality of life and prolonging survival. The advent of new drugs and new formulations of standard agents has led to better outcomes in patients with advanced or metastatic disease. These developments have also allowed a tailored therapeutic approach, in which the molecular biology of the tumour, the treatment history, and patient attitudes are taken into account in the decision-making process. Targeting drug delivery to the tumour is a promising mean of increasing the therapeutic index of highly active agents such as the taxanes, and nanoparticle albumin-bound paclitaxel (nab-paclitaxel), the first nanotechnology-based drug developed in cancer treatment, is one such advance. Data from randomized trials support the efficacy of single-agent nab-paclitaxel as first-line and further treatment lines in MBC at the registered 3-weekly schedule of 260 mg/m2, but emerging evidence suggests its activity as a weekly regimen or combined with other agents in various clinical scenarios. Thus, nab-paclitaxel seems to offer flexibility in terms of dosing schedules, allowing physicians to tailor the dose according to different clinical situations. This paper reviews the clinical trial background for nab-paclitaxel in MBC, focusing on specific ‘difficult-to-treat’ patient populations, such as taxane-pretreated or elderly women, as well as those with triple-negative, HER2-positive and poor-prognostic-factors disease. Moving beyond evidence-based information, ‘real life’ available experiences are also discussed with the aim of providing an update for daily clinical practice.

  2. Paralytic ileus due to a novel anticancer drug, nab-paclitaxel: A case report

    PubMed Central

    JIAO, XIAO-DONG; LUO, XIU; QIN, WEN-XING; YUAN, LING-YAN; ZANG, YUAN-SHENG

    2016-01-01

    Nab-paclitaxel is a recently emerged chemotherapy drug, which is widely used for the treatment of multiple types of cancer. The prospects of this novel drug are very bright as a result of its higher efficacy and lower toxicity compared with paclitaxel. Hence, the side effect, even if rare, require attention in clinical practice. The present study described an unusual case of nab-paclitaxel-associated paralytic ileus. To the best of our knowledge, this is the first report to demonstrate that nab-paclitaxel may lead to acute intestinal obstruction. Since nab-paclitaxel will be used more frequently, this unusual side effect might be encountered by a clinical oncologist and must be treated correctly. This is the first reported case, to the best of our knowledge, of paralytic ileus caused by nab-paclitaxel, which will be widely used as a novel anticancer drug. PMID:27123288

  3. Subcutaneous administration of paclitaxel in dogs with cancer: A preliminary study

    PubMed Central

    Silva, Daniella M.; Franciosi, Aline I.; Pezzini, Paula C.F.; Guérios, Simone D.

    2015-01-01

    Intravenous paclitaxel has been underused in dogs due to severe and acute hypersensitivity reactions. Subcutaneous (SC) administration of paclitaxel and its safety are unknown. In this preliminary study, SC administration of paclitaxel was evaluated for hypersensitivity reactions and toxicity in 21 dogs with advanced cancer. Dogs received 1 to 5 paclitaxel doses, ranging from 85 to 170 mg/m2, SC every 14 or 21 days. A total of 40 paclitaxel doses were administered and none of the 21 dogs developed systemic or acute local hypersensitivity reactions. Severe skin lesions at the injection site developed in 2 dogs after the 4th injection at the same location. Grade 4 neutropenia was observed in 50% of the dogs 5 days after the first treatment at 115 mg/m2 (n = 14). Two animals developed Grade 5 diarrhea and died likely due to hemodynamic failure or sepsis. Paclitaxel can be administered SC in dogs with no hypersensitivity reaction. PMID:26246628

  4. Resistance to paclitaxel increases the sensitivity to other microenvironmental stresses in prostate cancer cells

    PubMed Central

    Li, Youqiang; Zeng, Yu; Mooney, Steven M.; Yin, Bo; Mizokami, Atsushi; Namiki, Mikio; Getzenberg, Robert H.

    2011-01-01

    The microenvironment is central to many aspects of cancer pathobiology and has been proposed to play a role in the development of cancer cell resistant to therapy. To examine the response to microenvironmental conditions, two paclitaxel resistant prostate cancer cell lines (stable and reversible) and one reversible heat resistant cell line were studied. In comparison to their parental cell lines, both paclitaxel resistant cell lines (stable and reversible) were more sensitive to microenvironmental heat, potentially yielding a synergistic therapeutic opportunity. In the two phenotypic cells repopulated after acute heat or paclitaxel treatments, there was an inverse correlation between paclitaxel and heat resistance: resistance to paclitaxel imparted sensitivity to heat; resistance to heat imparted sensitivity to paclitaxel. These studies indicate that as cancer cells evolve resistance to single microenvironmental stress they may be more sensitive to others, perhaps allowing us to design new approaches for prostate cancer therapy. PMID:21465536

  5. Phase I Study of Pazopanib in Combination with Weekly Paclitaxel in Patients with Advanced Solid Tumors

    PubMed Central

    Dowlati, Afshin; Jones, Suzanne F.; Infante, Jeffrey R.; Nishioka, Jennifer; Fang, Lei; Hodge, Jeffrey P.; Gainer, Shelby D.; Arumugham, Thangam; Suttle, A. Benjamin; Dar, Mohammed M.; Lager, Joanne J.; Burris, Howard A.

    2010-01-01

    Purpose. To evaluate the maximum tolerated regimen (MTR), dose-limiting toxicities, and pharmacokinetics of pazopanib, an oral small-molecule tyrosine kinase inhibitor of vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit, in combination with paclitaxel. Patients and Methods. Pazopanib was given daily with weekly paclitaxel on days 1, 8, and 15 every 28 days. Dose levels of pazopanib (mg/day)/paclitaxel (mg/m2) were 400/15, 800/15, 800/50, and 800/80. An expanded cohort was enrolled at the MTR. Plasma samples were collected to evaluate the effect of pazopanib, an inhibitor of cytochrome P450 (CYP)3A4, on the pharmacokinetics of paclitaxel, a CYP3A4 and CYP2C8 substrate. Results. Of 26 enrolled patients, 17 were treated at the MTR of 800 mg pazopanib and 80 mg/m2 paclitaxel. Dose-limiting toxicities included a grade 3 abscess and grade 2 hyperbilirubinemia. Other toxicities included elevated liver transaminases and diarrhea. Six patients (23%) had partial responses and 15 patients (58%) had stable disease. Administration of 800 mg pazopanib resulted in a 14% lower paclitaxel clearance and a 31% higher paclitaxel maximal concentration than with administration of paclitaxel alone at 15, 50, and 80 mg/m2. At the MTR, coadministration of 800 mg pazopanib and 80 mg/m2 paclitaxel resulted in a 26% higher geometric mean paclitaxel area under the curve. Conclusion. Pazopanib, at a dose of 800 mg daily, can be safely combined with a therapeutic dose of paclitaxel at 80 mg/m2 when administered on days 1, 8, and 15, every 28 days. The observed greater plasma concentrations of paclitaxel given concurrently with pazopanib suggest that pazopanib is a weak inhibitor of CYP3A4 and CYP2C8. PMID:21147873

  6. Extraction and RP-HPLC determination of taxol in rat plasma, cell culture and quality control samples

    PubMed Central

    Tekade, Rakesh Kumar; D'Emanuele, Antony; Elhissi, Abdelbary; Agrawal, Ashish; Jain, Anurekha; Arafat, Basel Tawfiq; Jain, Narendra Kumar

    2013-01-01

    A rapid, sensitive, selective and validated reverse phase high-performance liquid chromatography (RP-HPLC) method for the estimation of paclitaxel in micro-sample of rat plasma and in culture of cancer cells was performed in this study. The mobile phase consisted of an optimized mixture of methanol:water: trifluroacetic acid (80: 20: 0.1, v/v/v). Column elution at a flow rate of 1 mL/minute with UV detection at 225 nm at room temperature was used. The RP-HPLC method was successfully applied for the determination of paclitaxel in plasma samples and in culture of cancer cells with nano-quantity of estimation. The validation studies were performed in accordance with the International Conference on Harmonization (ICH) guidelines. The intra- and inter-day precision showed that the coefficients of variation ranged from 1.07% to 4.27% at different levels of concentrations. To the best of our knowledge, this study also reported for the first time the optimization of different solvents for effective extraction of paclitaxel wherein tert.-butyl methyl ether (TBME): diethyl ether (DEE) in 50: 50 v/v composition was found most efficient with extraction efficiency ranging between 77.99% and 91.74% and between 76.14 and 93.66% in the plasma and cell culture, respectively. This proposed method was successfully applied to study the pharmacokinetics of paclitaxel and the influence of verapamil and all-trans retinoic acid (atRA) on paclitaxel pharmacokinetics in rat models. This proposed method might emerge as a valuable aid in the laboratory monitoring of paclitaxel in a variety of in vitro as well as in vivo scenarios. PMID:24086173

  7. Stopping paclitaxel premedication after two doses in patients not experiencing a previous infusion hypersensitivity reaction

    PubMed Central

    Vargo, Craig; Vincent, Mary; Shaver, Katy; Phillips, Gary; Layman, Rachel; Macrae, Erin; Mrozek, Ewa; Ramaswamy, Bhuvaneswari; Wesolowski, Robert; Shapiro, Charles L.; Lustberg, Maryam B.

    2016-01-01

    Purpose Paclitaxel-based chemotherapy continues to be an integral component of breast cancer treatment. Prolonged use of paclitaxel may result in repeated doses of premedications that can have unwanted side effects. Infusion hypersensitivity reactions occurring beyond the second dose of paclitaxel are infrequent and not well characterized. We previously published the results of a small, prospective pilot trial demonstrating the safety and feasibility of discontinuing premedications in patients who received the first two doses of paclitaxel-based chemotherapy without experiencing an infusion hypersensitivity reaction. In this study, we aimed to retrospectively characterize the incidence of rescue medication using this abbreviated premedication regimen in our institution following the publication of the pilot study. Methods Patients with stages I–IV breast cancer who received paclitaxel from January 2011 through June 2013 were screened for eligibility. Patients who did not experience an infusion hypersensitivity reaction with their first or second dose of paclitaxel and discontinued paclitaxel premedication for subsequent doses were included in this analysis. The primary endpoint was to estimate the incidence of rescue medication use for the treatment of paclitaxel infusion hypersensitivity during doses three to six of paclitaxel in the study population. Results In total, 449 patients received paclitaxel-based chemotherapy for the treatment of breast cancer during the interval time period. After receiving the first two doses of paclitaxel-based chemotherapy without experiencing an infusion hypersensitivity reaction, 234 breast cancer patients had their premedications discontinued for all remaining paclitaxel doses. These patients tolerated future paclitaxel doses without severe or life-threatening complications related to infusion hypersensitivity. The majority of patients did not have any symptoms of an infusion reaction, with only two of these patients requiring rescue medication to treat an infusion hypersensitivity reaction with subsequent paclitaxel doses (0.85; 95% confidence interval (CI), 0.10–3.05%). Conclusions Discontinuation of paclitaxel premedications in breast cancer patients who have not experienced an infusion hypersensitivity reaction with the first two doses of paclitaxel is not associated with increased rate of rescue medication use for infusion hypersensitivity. PMID:25519756

  8. Vasodilatation in the rat dorsal hindpaw induced by activation of sensory neurons is reduced by Paclitaxel

    PubMed Central

    Gracias, N.G.; Cummins, T.R.; Kelley, M.R.; Basile, D.P.; Iqbal, T.; Vasko, M.R.

    2010-01-01

    Peripheral neuropathy is a major side effect following treatment with the cancer chemotherapeutic drug paclitaxel. Whether paclitaxel-induced peripheral neuropathy is secondary to altered function of small diameter sensory neurons remains controversial. To ascertain whether the function of the small diameter sensory neurons was altered following systemic administration of paclitaxel, we injected male Sprague Dawley rats with 1 mg/kg paclitaxel every other day for a total of four doses and examined vasodilatation in the hindpaw at day 14 as an indirect measure of calcitonin gene related peptide (CGRP) release. In paclitaxel-treated rats, the vasodilatation induced by either intradermal injection of capsaicin into the hindpaw or electrical stimulation of the sciatic nerve was significantly attenuated in comparison to vehicle-injected animals. Paclitaxel treatment, however, did not affect direct vasodilatation induced by intradermal injection of methacholine or CGRP, demonstrating that the blood vessels’ ability to dilate was intact. Paclitaxel treatment did not alter the compound action potentials or conduction velocity of C-fibers. The stimulated release of CGRP from the central terminals in the spinal cord was not altered in paclitaxel-injected animals. These results suggest that paclitaxel affects the peripheral endings of sensory neurons to alter transmitter release, and this may contribute to the symptoms seen in neuropathy. PMID:20932997

  9. Archaeosome: as new drug carrier for delivery of Paclitaxel to breast cancer.

    PubMed

    Alavi, Seyed Ebrahim; Mansouri, Hamidreza; Esfahani, Maedeh Koohi Moftakhari; Movahedi, Fatemeh; Akbarzadeh, Azim; Chiani, Mohsen

    2014-04-01

    In the present study, paclitaxel was archaeosomed to reduce side effects and improve its therapeutic index. Carriers have made a big evolution in treatment of many diseases in recent years. Lipid carriers are of special importance among carriers. Archaeosome is one of the lipid carriers. Paclitaxel is one of the drugs used to treat breast cancer which has some unwanted side effects despite its therapeutic effects. Archaeosomes were extracted from methanogenic archi bacteria and synthesized with a certain ratio of paclitaxel in PBS. The mean diameter of archaeosomal paclitaxel was measured by Zeta sizer instrument, Drug releasing of archaeosomal paclitaxel was examined within 26 h which results showed that the most drug releasing occurs during first 3 h. The cytotoxicity effect of archaeosomal paclitaxel on breast cancer's cell line was evaluated by MTT assay which results showed that the cytotoxicity effect of archaeosomal paclitaxel on breast cancer's cell line is more than that of the standard paclitaxel formulation. The results indicated that new drug delivery of paclitaxel using archaeosome, increases the therapeutic index of the drug. PMID:24757295

  10. Paclitaxel stimulates chromosomal fusion and instability in cells with dysfunctional telomeres: Implication in multinucleation and chemosensitization

    SciTech Connect

    Park, Jeong-Eun; Woo, Seon Rang; Department of Biochemistry, College of Medicine, Korea University, Seoul 136-705 ; Kang, Chang-Mo; Juhn, Kyoung-Mi; Ju, Yeun-Jin; Shin, Hyun-Jin; Joo, Hyun-Yoo; Park, Eun Ran; Park, In-chul; Hong, Sung Hee; Hwang, Sang-Gu; Lee, Jung-Kee; Kim, Hae Kwon; Cho, Myung-Haing; Park, Gil Hong; Lee, Kee-Ho

    2011-01-14

    Research highlights: {yields} Paclitaxel serves as a stimulator of chromosomal fusion in cells in which telomeres are dysfunctional. {yields} Typical fusions involve p-arms, but paclitaxel-induced fusions occur between both q- and p-arms. {yields} Paclitaxel-stimulated fusions in cells in which telomeres are dysfunctional evoke prolonged G2/M cell cycle arrest and delay multinucleation. {yields} Upon telomere erosion, paclitaxel promotes chromosomal instability and subsequent apoptosis. {yields} Chromosomal fusion enhances paclitaxel chemosensitivity under telomere dysfunction. -- Abstract: The anticancer effect of paclitaxel is attributable principally to irreversible promotion of microtubule stabilization and is hampered upon development of chemoresistance by tumor cells. Telomere shortening, and eventual telomere erosion, evoke chromosomal instability, resulting in particular cellular responses. Using telomerase-deficient cells derived from mTREC-/-p53-/- mice, here we show that, upon telomere erosion, paclitaxel propagates chromosomal instability by stimulating chromosomal end-to-end fusions and delaying the development of multinucleation. The end-to-end fusions involve both the p- and q-arms in cells in which telomeres are dysfunctional. Paclitaxel-induced chromosomal fusions were accompanied by prolonged G2/M cell cycle arrest, delayed multinucleation, and apoptosis. Telomere dysfunctional cells with mutlinucleation eventually underwent apoptosis. Thus, as telomere erosion proceeds, paclitaxel stimulates chromosomal fusion and instability, and both apoptosis and chemosensitization eventually develop.

  11. Nab-paclitaxel, docetaxel, or solvent-based paclitaxel in metastatic breast cancer: a cost-utility analysis from a Chinese health care perspective

    PubMed Central

    Dranitsaris, George; Yu, Bo; King, Jennifer; Kaura, Satyin; Zhang, Adams

    2015-01-01

    Background Paclitaxel and docetaxel are commonly used for metastatic breast cancer in the People’s Republic of China. To improve the safety and efficacy of paclitaxel, an albumin-bound formulation (nab) is now available in the People’s Republic of China (Abraxane®). To provide health economic data for the key stakeholders, a cost-utility analysis comparing nab-paclitaxel to docetaxel, both as alternatives to paclitaxel, was conducted. Methods A meta-analysis of clinical outcomes Phase III trials comparing nab-paclitaxel (260 mg/m2 every [q] 3 weeks) or branded docetaxel (100 mg/m2 q 3 weeks), to solvent-based branded paclitaxel (175 mg/m2 q 3 weeks) was undertaken to provide safety and clinical data. Resource use data for the delivery of anticancer therapy and for the treatment of grade 3/4 toxicity was collected from a time and motion study conducted in three Chinese cancer centers and from a survey of clinicians. Using the Time Trade-Off technique, health utility estimates were derived from interviewing 28 breast cancer patients from one cancer center in the People’s Republic of China. All costs were reported in 2014 US dollars. Results Nab-paclitaxel had the most favorable safety profile, characterized with the lowest incidence of grade 3/4 neutropenia, febrile neutropenia, anemia, and stomatitis. When the median number of cycles delivered from the clinical trials was applied, nab-paclitaxel had a cost per course of $19,752 compared with $8,940 and $13,741 for paclitaxel and docetaxel, respectively. As an alternative to paclitaxel, the cost per quality-adjusted life-year (QALY) gained with nab-paclitaxel suggested better value than with docetaxel ($57,900 vs $130,600). Conclusion Nab-paclitaxel appears to be a cost-effective option compared with docetaxel and paclitaxel, for metastatic breast cancer in the People’s Republic of China. PMID:25999749

  12. Effects of taxol resistance gene 1 expression on the chemosensitivity of SGC-7901 cells to oxaliplatin

    PubMed Central

    LIU, LIANCHENG; BAI, ZHIGANG; MA, XUEMEI; WANG, TINGTING; YANG, YAO; ZHANG, ZHONGTAO

    2016-01-01

    The present study aimed to evaluate the role of taxol resistance gene 1 (Txr1) in the development of oxaliplatin (L-OHP) resistance in gastric cancer (GC). Using SGC-7901 cells as a model, Txr1 was exogenously expressed or knocked down using small interfering RNA. Quantitative polymerase chain reaction (qPCR) and western blotting were performed to establish whether the Txr1 gene is involved in chemoresistance, and cell proliferation was assessed using an MTS assay. To this end, the mRNA and protein levels of Txr1, thrombospondin-1 and excision repair cross-complementing 1 protein were measured using qPCR and western blotting, respectively. Txr1-knockdown significantly increased the sensitivity of the SGC-7901 cells to L-OHP, whereas Txr1 overexpression promoted the resistance of the SGC-7901 cells to L-OHP. Exogenous Txr1 expression in the SGC-7901 cells induced L-OHP resistance, and the siRNA knockdown of Txr1 sensitized the human GC cells to L-OHP. Txr1 is, therefore, likely to play a role in L-OHP resistance, acting via TSP1, and should be investigated as a potential therapeutic target in the treatment of GC. PMID:26998002

  13. Overcoming heterologous protein interdependency to optimize P450-mediated Taxol precursor synthesis in Escherichia coli.

    PubMed

    Biggs, Bradley Walters; Lim, Chin Giaw; Sagliani, Kristen; Shankar, Smriti; Stephanopoulos, Gregory; De Mey, Marjan; Ajikumar, Parayil Kumaran

    2016-03-22

    Recent advances in metabolic engineering have demonstrated the potential to exploit biological chemistry for the synthesis of complex molecules. Much of the progress to date has leveraged increasingly precise genetic tools to control the transcription and translation of enzymes for superior biosynthetic pathway performance. However, applying these approaches and principles to the synthesis of more complex natural products will require a new set of tools for enabling various classes of metabolic chemistries (i.e., cyclization, oxygenation, glycosylation, and halogenation) in vivo. Of these diverse chemistries, oxygenation is one of the most challenging and pivotal for the synthesis of complex natural products. Here, using Taxol as a model system, we use nature's favored oxygenase, the cytochrome P450, to perform high-level oxygenation chemistry inEscherichia coli An unexpected coupling of P450 expression and the expression of upstream pathway enzymes was discovered and identified as a key obstacle for functional oxidative chemistry. By optimizing P450 expression, reductase partner interactions, and N-terminal modifications, we achieved the highest reported titer of oxygenated taxanes (∼570 ± 45 mg/L) inE. coli.Altogether, this study establishesE. colias a tractable host for P450 chemistry, highlights the potential magnitude of protein interdependency in the context of synthetic biology and metabolic engineering, and points to a promising future for the microbial synthesis of complex chemical entities. PMID:26951651

  14. PEGylated Nanoparticles Obtained through Emulsion Polymerization as Paclitaxel Carriers.

    PubMed

    Colombo, Claudio; Morosi, Lavinia; Bello, Ezia; Ferrari, Raffaele; Licandro, Simonetta Andrea; Lupi, Monica; Ubezio, Paolo; Morbidelli, Massimo; Zucchetti, Massimo; D'Incalci, Maurizio; Moscatelli, Davide; Frapolli, Roberta

    2016-01-01

    Polymer nanoparticles (NPs) represent a promising way to deliver poorly water-soluble anticancer drugs without the use of unwanted excipients, whose presence can be the cause of severe side effects. In this work, a Cremophor-free formulation for paclitaxel (PTX) has been developed by employing PEGylated polymer nanoparticles (NPs) as drug delivery carriers based on modified poly(ε-caprolactone) macromonomers and synthesized through free radical emulsion polymerization. Paclitaxel was loaded in the NPs in a postsynthesis process which allowed to obtain a drug concentration suitable for in vivo use. In vivo experiments on drug biodistribution and therapeutic efficacy show comparable behavior between the NPs and the Cremophor formulation, also showing good tolerability of the new formulation proposed. PMID:26623665

  15. Transcriptomic profiling of taxol-resistant ovarian cancer cells identifies FKBP5 and the androgen receptor as critical markers of chemotherapeutic response

    PubMed Central

    Chang, Pu-Yuan; Lu, Hsing-Pang; Chao, Chuck C.-K.

    2014-01-01

    Taxol is a mitotoxin widely used to treat human cancers, including of the breast and ovary. However, taxol resistance (txr) limits treatment efficacy in human patients. To study chemoresistance in ovarian cancer, we established txr ovarian carcinoma cells derived from the SKOV3 cell lineage. The cells obtained were cross-resistant to other mitotoxins such as vincristine while they showed no resistance to the genotoxin cisplatin. Transcriptomic analysis identified 112 highly up-regulated genes in txr cells. Surprisingly, FK506-binding protein 5 (FKBP5) was transiently up-regulated 100-fold in txr cells but showed decreased expression in prolonged culture. Silencing of FKBP5 sensitized txr cells to taxol, whereas ectopic expression of FKBP5 increased resistance to the drug. Modulation of FKBP5 expression produced similar effects in response to vincristine but not to cisplatin. We observed that a panel of newly identified txr genes was trancriptionally regulated by FKBP5 and silencing of these genes sensitized cells to taxol. Notably, immunoprecipitation experiments revealed that FKBP5 forms a protein complex with the androgen receptor (AR), and this complex regulates the transcriptional activity of both proteins. Furthermore, we found that the Akt kinase pathway is regulated by FKBP5. These results indicate that the FKBP5/AR complex may affect cancer cell sensitivity to taxol by regulating expression of txr genes. Our findings suggest that mitotoxin-based treatment against ovarian cancer should be avoided when the Akt/FKBP5/AR axis is activated. PMID:25460502

  16. Bilateral Cystoid Macular Edema Secondary to Paclitaxel Treatment.

    PubMed

    Tezcan, Yilmaz; Surmeli, Mustafa; Tastekin, Didem; Koc, Mehmet

    2015-09-01

     Cystoid macular edema is rarely observed secondary to paclitaxel treatment. A 55-year-old female patient was applied five cures of paclitaxel and carboplatin chemotherapy after being diagnosed with metastatic ovarian cancer. The patient had a normal bilateral vision prior to the chemotherapy treatments. After the fifth cure, the patient complained of bilateral vision loss, which was more severe in the left eye. Ophthalmologic examination revealed that right eye vision was 4/10 blurred without glasses and 7/10 blurred with glasses, left eye vision was 1/10 blurred without glasses and 4/10 blurred with glasses. Pathology was not detected during the biomicroscopic examination. Fundus examination of the patient revealed pigment epithelium irregularity, which was found to be less in the right eye, and it was found a decrease in foveal cavity. For fundus examination, the patient underwent fundus fluorescein angiography (FFA) and optical coherence tomography (OCT). FFA revealed fluorescein leakage and cystoid appearance particularly more apparent in the left eye. Thickening in the macula and cystoid space was observed particularly more in the left eye in the OCT measurement. In conclusion, we presented our case as a rarely observed cystoid macular edema secondary to paclitaxel treatment. PMID:26317603

  17. Synthesis, physico-chemical and biological characterization of a paclitaxel macromolecular prodrug.

    PubMed

    Cavallaro, G; Licciardi, M; Caliceti, P; Salmaso, S; Giammona, G

    2004-07-01

    Paclitaxel was attached to poly(hydroxyethylaspartamide) via a succinic spacer arm by a two-step protocol: (1) synthesis of 2'-O-succinyl-paclitaxel; (2) synthesis of PHEA-2'-O-succinyl-paclitaxel. The 2'-O-succinyl-paclitaxel derivative and the macromolecular conjugate were characterized by UV, IR, NMR and mass spectrometry analysis. The reaction yields were over 95% and the purity of products over 98%. Paclitaxel release and degradation from 2'-O-succinyl-paclitaxel occurred at a faster rate at pH 5.5 than 7.4. After 30 h of incubation at pH 5.5 and 7.4 the released free paclitaxel was about 40 and 20%, respectively. In plasma both drug release and degradation were found to occur at a higher rate than in buffer at pH 7.4 suggesting that an enzymatic mechanism could be involved. The paclitaxel release and degradation from PHEA-2'-O-succinyl-paclitaxel were negligible at pH 5.5 and 7.4 and very slow in plasma. Investigation carried out using murine myeloid cell line showed that the polymeric prodrug maintains partial pharmacological activity of paclitaxel. The DL50 of the conjugate (over 40 ng/ml) as compared to free paclitaxel (about 1 ng/ml) was correlated to the slow drug release. Finally a pharmacokinetic study carried out by intravenous inoculation of the macromolecular prodrug to mice demonstrated that the polymer conjugation modify dramatically the in vivo fate of the drug. The conjugate disappeared from the bloodstream much more quickly as compared to both free drug and naked polymer. Massive accumulation of bioconjugate in the liver (80% of the dose) was found to persist throughout 1 week. PMID:15207549

  18. Evaluation of the Tubulin-Bound Paclitaxel Conformation: Synthesis, Biology and SAR Studies of C-4 to C-3′ Bridged Paclitaxel Analogs

    PubMed Central

    Ganesh, Thota; Yang, Chao; Norris, Andrew; Glass, Tom; Bane, Susan; Ravindra, Rudravajhala; Banerjee, Abhijit; Metaferia, Belhu; Thomas, Shala L.; Giannakakou, Paraskevi; Alcaraz, Ana A.; Lakdawala, Ami S.; Snyder, James P.; Kingston, David G. I.

    2008-01-01

    The important anticancer drug paclitaxel binds to the β-subunit of the αβ-tubulin dimer in the microtubule in a stoichiometric ratio, promoting microtubule polymerization and stability. The conformation of microtubule-bound drug has been the subject of intense study, and various suggestions have been made for it. In previous work we presented experimental and theoretical evidence that paclitaxel adopts a T-shaped conformation when it is bound to tubulin. In this study we report additional experimental data and calculations that delineate the allowable parameters for effective paclitaxel-tubulin interactions. PMID:17263521

  19. Paclitaxel-resistant cells have a mutation in the paclitaxel-binding region of beta-tubulin (Asp26Glu) and less stable microtubules.

    PubMed

    Hari, Malathi; Loganzo, Frank; Annable, Tami; Tan, Xingzhi; Musto, Sylvia; Morilla, Daniel B; Nettles, James H; Snyder, James P; Greenberger, Lee M

    2006-02-01

    Resistance to paclitaxel-based therapy is frequently encountered in the clinic. The mechanisms of intrinsic or acquired paclitaxel resistance are not well understood. We sought to characterize the resistance mechanisms that develop upon chronic exposure of a cancer cell line to paclitaxel in the presence of the P-glycoprotein reversal agent, CL-347099. The epidermoid tumor line KB-3-1 was exposed to increasing concentrations of paclitaxel and 5 micromol/L CL-347099 for up to 1 year. Cells grown in 15 nmol/L paclitaxel plus CL-347099 (KB-15-PTX/099) developed 18-fold resistance to paclitaxel and were dependent upon paclitaxel for maximal growth. They grew well and retained resistance to paclitaxel when grown in athymic mice. Cross-resistance (3- to 5-fold) was observed in tissue culture to docetaxel, the novel taxane MAC-321, and epothilone B. Collateral sensitivity (approximately 3-fold) was observed to the depolymerizing agents vinblastine, dolastatin-10, and HTI-286. KB-15-PTX/099-resistant cells did not overexpress P-glycoprotein nor did they have an alteration of [14C]paclitaxel accumulation compared with parental cells. However, a novel point mutation (T to A) resulting in Asp26 to glutamate substitution in class I (M40) beta-tubulin was found. Based on an electron crystallography structure of Zn-stabilized tubulin sheets, the phenyl ring of C-3' NHCO-C6H5 of paclitaxel makes contact with Asp26 of beta-tubulin, suggesting a ligand-induced mutation. Optimized model complexes of paclitaxel, docetaxel, and MAC-321 in beta-tubulin show a novel hydrogen bonding pattern for the glutamate mutant and rationalize the observed resistance profiles. However, a mutation in the paclitaxel binding pocket does not explain the phenotype completely. KB-15-PTX/099 cells have impaired microtubule stability as determined by a reduced percentage of tubulin in microtubules and reflected by less acetylated tubulin. These results suggest that a mutation in tubulin might affect microtubule stability as well as drug binding and contribute to the observed resistance profile. PMID:16505100

  20. Effects of Jia-Wei-Xiao-Yao-San on the Peripheral and Lymphatic Pharmacokinetics of Paclitaxel in Rats

    PubMed Central

    Hou, Mei-Ling; Lu, Chia-Ming

    2016-01-01

    Paclitaxel is effective against breast cancer. The herbal medicine, Jia-Wei-Xiao-Yao-San (JWXYS), is the most frequent prescription used to relieve the symptoms of breast cancer treatments. The aim of the study was to investigate the herb-drug interaction effects of a herbal medicine on the distribution of paclitaxel to lymph. A validated ultraperformance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) method was used to determine the paclitaxel levels in rat plasma and lymph after intravenous infusion of paclitaxel alone with or without 7 days of JWXYS pretreatment. The pharmacokinetic results indicate that paclitaxel concentrations in plasma exceeded those in lymph by approximately 3.6-fold. The biodistribution of paclitaxel from plasma to lymph was 39 ± 5%; however, this increased to 45 ± 4% with JWXYS pretreatment. With JWXYS pretreatment, the AUC and Cmax of paclitaxel in plasma were significantly reduced by approximately 1.5-fold, compared to paclitaxel alone. Additionally, JWXYS decreased the AUC and Cmax of paclitaxel in lymph. However, the lymph absorption rate of paclitaxel with or without JWXYS pretreatment was not significantly changed (27 ± 3 and 30 ± 2%, resp.). Our findings demonstrate that when paclitaxel is prescribed concurrently with herbal medicine, monitoring of the blood pharmacokinetics of paclitaxel is recommended. PMID:27057200

  1. Restoration of paclitaxel resistance by CDK1 intervention in drug-resistant ovarian cancer.

    PubMed

    Bae, Taejeong; Weon, Kwon-Yeon; Lee, Jeong-Won; Eum, Ki-Hwan; Kim, Sungchul; Choi, Jin Woo

    2015-12-01

    Epithelial ovarian cancer (EOC) commonly acquires resistance to chemotherapy, and this is the major obstacle to the better prognosis. Elucidating the molecular targets altered by chemotherapy is critically required to understand and overcome drug resistance. As a drug combination including paclitaxel is a prevalent prescription for treatment of EOC, to uncover gene expression altered in paclitaxel-resistant EOC, we analyzed multidirectional microarray profiles in both EOC cell lines and patients with paclitaxel resistance. Cyclin-dependent kinase 1 (CDK1) was found to be a potential target of transcription factors to regulate paclitaxel resistance. As a result of the subsequent pharmacogenomics analysis, CDK1 inhibitor alsterpaullone was also indicated as a promising chemical that may be used in combinatorial therapies to reverse paclitaxel-induced chemoresistance. Although a CDK1 inhibitor has the potential to kill cancer cells, short-term treatment over 2 weeks at sublethal doses effectively induced cell death only upon additional treatment with paclitaxel. A prominent reduction in the tumor growth rate was observed upon paclitaxel subsequent to alsterpaullone treatment in EOC xenograft model. Thus, we suggest that inhibition of CDK1 with alsterpaullone may be a novel therapeutic method to reverse paclitaxel-induced resistance in ovarian cancer cells. PMID:26442525

  2. Tumor-selective peptide-carrier delivery of Paclitaxel increases in vivo activity of the drug

    PubMed Central

    Brunetti, Jlenia; Pillozzi, Serena; Falciani, Chiara; Depau, Lorenzo; Tenori, Eleonora; Scali, Silvia; Lozzi, Luisa; Pini, Alessandro; Arcangeli, Annarosa; Menichetti, Stefano; Bracci, Luisa

    2015-01-01

    Taxanes are highly effective chemotherapeutic drugs against proliferating cancer and an established option in the standard treatment of ovarian and breast cancer. However, treatment with paclitaxel is associated with severe side effects, including sensory axonal neuropathy, and its poor solubility in water complicates its formulation. In this paper we report the in vitro and in vivo activity of a new form of paclitaxel, modified for conjugation with a tumor-selective tetrabranched peptide carrier (NT4). NT4 selectively targets tumor cells by binding to membrane sulfated glycosaminoglycans (GAG) and to endocytic receptors, like LRP1 and LRP6, which are established tumor markers. Biological activity of NT4-paclitaxel was tested in vitro on MDA-MB 231 and SKOV-3 cell lines, representing breast and ovarian cancer, respectively, and in vivo in an orthotopic mouse model of human breast cancer. Using in vivo bioluminescence imaging, we found that conjugation of paclitaxel with the NT4 peptide led to increased therapeutic activity of the drug in vivo. NT4-paclitaxel induced tumor regression, whereas treatment with unconjugated paclitaxel only produced a reduction in tumor growth. Moreover, unlike paclitaxel, NT4-paclitaxel is very hydrophilic, which may improve its pharmacokinetic profile and allow the use of less toxic dilution buffers, further decreasing its general chemotherapic toxicity. PMID:26626158

  3. TXNDC17 promotes paclitaxel resistance via inducing autophagy in ovarian cancer

    PubMed Central

    Zhang, Song-Fa; Wang, Xin-Yu; Fu, Zhi-Qin; Peng, Qiao-Hua; Zhang, Jian-Yang; Ye, Feng; Fu, Yun-Feng; Zhou, Cai-Yun; Lu, Wei-Guo; Cheng, Xiao-Dong; Xie, Xing

    2015-01-01

    Paclitaxel is recommended as a first-line chemotherapeutic agent against ovarian cancer, but drug resistance becomes a major limitation of its success clinically. The key molecule or mechanism associated with paclitaxel resistance in ovarian cancer still remains unclear. Here, we showed that TXNDC17 screened from 356 differentially expressed proteins by LC-MS/MS label-free quantitative proteomics was more highly expressed in paclitaxel-resistant ovarian cancer cells and tissues, and the high expression of TXNDC17 was associated with poorer prognostic factors and exhibited shortened survival in 157 ovarian cancer patients. Moreover, paclitaxel exposure induced upregulation of TXNDC17 and BECN1 expression, increase of autophagosome formation, and autophagic flux that conferred cytoprotection for ovarian cancer cells from paclitaxel. TXNDC17 inhibition by siRNA or enforced overexpression by a pcDNA3.1(+)-TXNDC17 plasmid correspondingly decreased or increased the autophagy response and paclitaxel resistance. Additionally, the downregulation of BECN1 by siRNA attenuated the activation of autophagy and cytoprotection from paclitaxel induced by TXNDC17 overexpression in ovarian cancer cells. Thus, our findings suggest that TXNDC17, through participation of BECN1, induces autophagy and consequently results in paclitaxel resistance in ovarian cancer. TXNDC17 may be a potential predictor or target in ovarian cancer therapeutics. PMID:25607466

  4. Paclitaxel-induced epithelial damage and ectopic MMP-13 expression promotes neurotoxicity in zebrafish

    PubMed Central

    Lisse, Thomas S.; Middleton, Leah J.; Pellegrini, Adriana D.; Martin, Paige B.; Spaulding, Emily L.; Lopes, Olivia; Brochu, Elizabeth A.; Carter, Erin V.; Waldron, Ashley; Rieger, Sandra

    2016-01-01

    Paclitaxel is a microtubule-stabilizing chemotherapeutic agent that is widely used in cancer treatment and in a number of curative and palliative regimens. Despite its beneficial effects on cancer, paclitaxel also damages healthy tissues, most prominently the peripheral sensory nervous system. The mechanisms leading to paclitaxel-induced peripheral neuropathy remain elusive, and therapies that prevent or alleviate this condition are not available. We established a zebrafish in vivo model to study the underlying mechanisms and to identify pharmacological agents that may be developed into therapeutics. Both adult and larval zebrafish displayed signs of paclitaxel neurotoxicity, including sensory axon degeneration and the loss of touch response in the distal caudal fin. Intriguingly, studies in zebrafish larvae showed that paclitaxel rapidly promotes epithelial damage and decreased mechanical stress resistance of the skin before induction of axon degeneration. Moreover, injured paclitaxel-treated zebrafish skin and scratch-wounded human keratinocytes (HEK001) display reduced healing capacity. Epithelial damage correlated with rapid accumulation of fluorescein-conjugated paclitaxel in epidermal basal keratinocytes, but not axons, and up-regulation of matrix-metalloproteinase 13 (MMP-13, collagenase 3) in the skin. Pharmacological inhibition of MMP-13, in contrast, largely rescued paclitaxel-induced epithelial damage and neurotoxicity, whereas MMP-13 overexpression in zebrafish embryos rendered the skin vulnerable to injury under mechanical stress conditions. Thus, our studies provide evidence that the epidermis plays a critical role in this condition, and we provide a previously unidentified candidate for therapeutic interventions. PMID:27035978

  5. Preparation and biological activity of a paclitaxel-single-walled carbon nanotube complex.

    PubMed

    Fu, X D; Zhang, Y Y; Wang, X J; Shou, J X; Zhang, Z Z; Song, L J

    2014-01-01

    Single-walled carbon nanotubes (SWCNTs) have unique transmembrane abilities. The huge superficial area and abundance of π electrons confer SWCNTs perfect absorptive capability toward proteins, nucleates, and many drugs. These characteristics make SWCNTs a new and efficient drug carrier. The purpose of this study was to disperse SWCNTs in water and have paclitaxel absorbed onto them in order to construct an asparagine-glycine-arginine (NGR)-SWCNT-Paclitaxel complex as a targeting nanoparticle system. The NGR-SWCNT-Paclitaxel complex was systematically studied, and analytical methods, including spectrophotometry for SWCNTs and high-performance liquid chromatography for paclitaxel, were employed. The preparation and the prescription of the NGR-SWCNT-Paclitaxel complex lyophilized powder were investigated. MCF-7 cancer cells, Sprague-Dawley rats, and S180 tumor-bearing mice were used as experimental subjects to evaluate the in vitro and in vivo activity of NGR-SWCNT-Paclitaxel complex dispersion. The complex dispersion showed obvious inhibition activity against MCF-7 cancer cells. Within 1 h, the NGR-SWCNT-Paclitaxel complex could be transferred to cells, and sustained the release of drugs. In addition, the tumor and liver targeting and improved therapeutic effects of the NGR-SWCNT-Paclitaxel complex were confirmed. PMID:24668633

  6. MiR-125a promotes paclitaxel sensitivity in cervical cancer through altering STAT3 expression.

    PubMed

    Fan, Z; Cui, H; Yu, H; Ji, Q; Kang, L; Han, B; Wang, J; Dong, Q; Li, Y; Yan, Z; Yan, X; Zhang, X; Lin, Z; Hu, Y; Jiao, S

    2016-01-01

    Cervical cancer (CC) is one of the most common malignancies in women. Paclitaxel is the front-line chemotherapeutic agent for treating CC. However, its therapeutic efficacy is limited because of chemoresistance, the mechanism of which remains poorly understood. Here, we used microRNA (miRNA) arrays to compare miRNA expression levels in the CC cell lines, HeLa and CaSki, with their paclitaxel resistance counterparts, HeLa/PR and CaSki/PR. We demonstrate that miR-125a was one of most significantly downregulated miRNAs in paclitaxel-resistant cells, which also acquired cisplatin resistance. And that the upregulation of miR-125a sensitized HeLa/PR and CaSki/PR cells to paclitaxel both in vitro and in vivo and to cisplatin in vitro. Moreover, we determined that miR-125a increased paclitaxel and cisplatin sensitivity by downregulating STAT3. MiR-125a enhanced paclitaxel and cisplatin sensitivity by promoting chemotherapy-induced apoptosis. Clinically, miR-125a expression was associated with an increased responsiveness to paclitaxel combined with cisplatin and a more favorable outcome. These data indicate that miR-125a may be a useful method to enable treatment of chemoresistant CC and may also provide a biomarker for predicting paclitaxel and cisplatin responsiveness in CC. PMID:26878391

  7. Thermoreversible Pluronic® F127-based hydrogel containing liposomes for the controlled delivery of paclitaxel: in vitro drug release, cell cytotoxicity, and uptake studies

    PubMed Central

    Nie, Shufang; Hsiao, WL Wendy; Pan, Weisan; Yang, Zhijun

    2011-01-01

    Purpose To develop an in situ gel system comprising liposome-containing paclitaxel (PTX) dispersed within the thermoreversible gel (Pluronic® F127 gel) for controlled release and improved antitumor drug efficiency. Methods The dialysis membrane and membrane-less diffusion method were used to investigate the in vitro drug release behavior. Differential scanning calorimetry (DSC) thermal analysis was used to investigate the “micellization” and “sol/gel transition” process of in situ gel systems. In vitro cytotoxicity and drug uptake in KB cancer cells were determined by MTT, intercellular drug concentration, and fluorescence intensity assay. Results The in vitro release experiment performed with a dialysis membrane model showed that the liposomal gel exhibited the longest drug-release period compared with liposome, general gel, and commercial formulation Taxol®. This effect is presumably due to the increased viscosity of liposomal gel, which has the effect of creating a drug reservoir. Both drug and gel release from the in situ gel system operated under zero-order kinetics and showed a correlation of release of PTX with gel, indicating a predominating release mechanism of the erosion type. Dispersing liposomes into the gel replaced larger gel itself for achieving the same gel dissolution rate. Both the critical micelle temperature and the sol/gel temperature, detected by DSC thermal analysis, were shifted to lower temperatures by adding liposomes. The extent of the shifts depended on the amount of embedded liposomes. MTT assay and drug uptake studies showed that the treatment with PTX-loaded liposomal 18% Pluronic F127 yielded cytotoxicities, intercellular fluorescence intensity, and drug concentration in KB cells much higher than that of conventional liposome, while blank liposomal 18% Pluronic F127 gel was far less than the Cremophor EL® vehicle and empty liposomes. Conclusions A thermosensitive hydrogel with embedded liposome is a promising carrier for hydrophobic anticancer agents, to be used in parenteral formulations for treating local cancers. PMID:21499415

  8. Folate-mediated targeted and intracellular delivery of paclitaxel using a novel deoxycholic acid-O-carboxymethylated chitosan–folic acid micelles

    PubMed Central

    Wang, Feihu; Chen, Yuxuan; Zhang, Dianrui; Zhang, Qiang; Zheng, Dandan; Hao, Leilei; Liu, Yue; Duan, Cunxian; Jia, Lejiao; Liu, Guangpu

    2012-01-01

    Background A critical disadvantage for successful chemotherapy with paclitaxel (PTX) is its nontargeting nature to cancer cells. Folic acid has been employed as a targeting ligand of various anticancer agents to increase their cellular uptake within target cells since the folate receptor is overexpressed on the surface of such tumor cells. In this study, a novel biodegradable deoxycholic acid-O-carboxymethylated chitosan–folic acid conjugate (DOMC-FA) was used to form micelles for encapsulating the anticancer drug PTX. Methods and results The drug-loading efficiency, encapsulation efficiency, in vitro drug release and physicochemical properties of PTX-loaded micelles were investigated in detail. In vitro cell culture studies were carried out in MCF-7 cells, a human breast carcinoma cell line, with folate receptor overexpressed on its surface. An increased level of uptake of folate-conjugated micelles compared to plain micelles in MCF-7 cells was observed, and the enhanced uptake of folate-micelles mainly on account of the effective process of folate receptor-mediated endocytosis. The MTT assay, morphological changes, and apoptosis test implied that the folate-conjugated micelles enhanced the cell death by folate-mediated active internalization, and the cytotoxicity of the FA-micellar PTX (DOMC-FA/PTX) to cancer cells was much higher than micelles without folate (DOMC/PTX) or the commercially available injectable preparation of PTX (Taxol). Conclusion Results indicate that the PTX-loaded DOMC-FA micelle is a successful anticancertargeted drug-delivery system for effective cancer chemotherapy. PMID:22287842

  9. Enhancement of paclitaxel and carboplatin therapies by CCL2 blockade in ovarian cancers

    PubMed Central

    Moisan, Francois; Francisco, Edgar B.; Brozovic, Anamaria; Duran, George E.; Wang, Yan C.; Chaturvedi, Shalini; Seetharam, Shobha; Snyder, Linda A.; Doshi, Parul; Sikic, Branimir I.

    2016-01-01

    Ovarian cancer is associated with a leukocyte infiltrate and high levels of chemokines such as CCL2. We tested the hypothesis that CCL2 inhibition can enhance chemotherapy with carboplatin and paclitaxel. Elevated CCL2 expression was found in three non-MDR paclitaxel resistant ovarian cancer lines ES-2/TP, MES-OV/TP and OVCAR-3/TP, compared to parental cells. Mice xenografted with these cells were treated with the anti-human CCL2 antibody CNTO 888 and the anti-mouse MCP-1 antibody C1142, with and without paclitaxel or carboplatin. Our results show an additive effect of CCL2 blockade on the efficacy of paclitaxel and carboplatin. This therapeutic effect was largely due to inhibition of mouse stromal CCL2. We show that inhibition of CCL2 can enhance paclitaxel and carboplatin therapy of ovarian cancer. PMID:24816187

  10. Apoptosis induced by paclitaxel-loaded copolymer PLA-TPGS in Hep-G2 cells

    NASA Astrophysics Data System (ADS)

    Nguyen, Hoai Nam; Tran Thi, Hong Ha; Le Quang, Duong; Nguyen Thi, Toan; Tran Thi, Nhu Hang; Huong Le, Mai; Thu Ha, Phuong

    2012-12-01

    Paclitaxel is an important anticancer drug in clinical use for treatment of a variety of cancers. The clinical application of paclitaxel in cancer treatment is considerably limited due to its serious poor delivery characteristics. In this study paclitaxel-loaded copolymer poly(lactide)-d-α-tocopheryl polyethylene glycol 1000 succinate (PLA-TPGS) nanoparticles were prepared by a modified solvent extraction/evaporation technique. The characteristics of the nanoparticles, such as surface morphology, size distribution, zeta potential, solubility and apoptosis were investigated in vitro. The obtained spherical nanoparticles were negatively charged with a zeta potential of about -18 mV with the size around 44 nm and a narrow size distribution. The ability of paclitaxel-loaded PLA-TPGS nanoparticles to induce apoptosis in human hepatocellular carcinoma cell line (Hep-G2) indicates the possibility of developing paclitaxel nanoparticles as a potential universal cancer chemotherapeutic agent.

  11. In vitro and in vivo targeting effect of folate decorated paclitaxel loaded PLA-TPGS nanoparticles.

    PubMed

    Thu, Ha Phuong; Nam, Nguyen Hoai; Quang, Bui Thuc; Son, Ho Anh; Toan, Nguyen Linh; Quang, Duong Tuan

    2015-11-01

    Paclitaxel is one of the most effective chemotherapeutic agents for treating various types of cancer. However, the clinical application of paclitaxel in cancer treatment is considerably limited due to its poor water solubility and low therapeutic index. Thus, it requires an urgent solution to improve therapeutic efficacy of paclitaxel. In this study, folate decorated paclitaxel loaded PLA-TPGS nanoparticles were prepared by a modified emulsification/solvent evaporation method. The obtained nanoparticles were characterized by Field Emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared (FTIR) and Dynamic Light Scattering (DLS) method. The spherical nanoparticles were around 50 nm in size with a narrow size distribution. Targeting effect of nanoparticles was investigated in vitro on cancer cell line and in vivo on tumor bearing nude mouse. The results indicated the effective targeting of folate decorated paclitaxel loaded copolymer nanoparticles on cancer cells both in vitro and in vivo. PMID:26702264

  12. Pharmacological Modulation of the Mitochondrial Electron Transport Chain in Paclitaxel-Induced Painful Peripheral Neuropathy

    PubMed Central

    Griffiths, Lisa A.; Flatters, Sarah J.L.

    2015-01-01

    Paclitaxel is an effective first-line chemotherapeutic with the major dose-limiting side effect of painful neuropathy. Mitochondrial dysfunction and oxidative stress have been implicated in paclitaxel-induced painful neuropathy. Here we show the effects of pharmacological modulation of mitochondrial sites that produce reactive oxygen species using systemic rotenone (complex I inhibitor) or antimycin A (complex III inhibitor) on the maintenance and development of paclitaxel-induced mechanical hypersensitivity in adult male Sprague Dawley rats. The maximally tolerated dose (5 mg/kg) of rotenone inhibited established paclitaxel-induced mechanical hypersensitivity. However, some of these inhibitory effects coincided with decreased motor coordination; 3 mg/kg rotenone also significantly attenuated established paclitaxel-induced mechanical hypersensitivity without any motor impairment. The maximally tolerated dose (.6 mg/kg) of antimycin A reversed established paclitaxel-induced mechanical hypersensitivity without any motor impairment. Seven daily doses of systemic rotenone or antimycin A were given either after paclitaxel administration or before and during paclitaxel administration. Rotenone had no significant effect on the development of paclitaxel-induced mechanical hypersensitivity. However, antimycin A significantly inhibited the development of paclitaxel-induced mechanical hypersensitivity when given before and during paclitaxel administration but had no effect when given after paclitaxel administration. These studies provide further evidence of paclitaxel-evoked mitochondrial dysfunction in vivo, suggesting that complex III activity is instrumental in paclitaxel-induced pain. Perspective This study provides further in vivo evidence that mitochondrial dysfunction is a key contributor to the development and maintenance of chemotherapy-induced painful neuropathy. This work also indicates that selective modulation of the electron transport chain can induce antinociceptive effects in a preclinical model of paclitaxel-induced pain. PMID:26142652

  13. Development of an oral solid dispersion formulation for use in low-dose metronomic chemotherapy of paclitaxel.

    PubMed

    Moes, Johannes; Koolen, Stijn; Huitema, Alwin; Schellens, Jan; Beijnen, Jos; Nuijen, Bastiaan

    2013-01-01

    For the clinical development of low-dose metronomic (LDM) chemotherapy of paclitaxel, oral administration is vital. However, the development of an oral formulation is difficult due to paclitaxel's low oral bioavailability, caused by its low permeability and low solubility. We increased the oral bioavailability of paclitaxel by combining a pharmacokinetic booster, ritonavir, with a new oral solid dispersion formulation of paclitaxel. The combined use of Hansen solubility parameters and dissolution experiments resulted in the development of a solid dispersion formulation containing 1/11 w/w paclitaxel, 9/11 w/w polyvinylpyrrolidone (PVP) K30, and 1/11 w/w sodium lauryl sulfate (SLS). Analysis of the solid dispersion formulation by X-ray diffraction, Fourier transform infrared (FT-IR) spectroscopy, and modulated differential scanning calorimetry (mDSC) confirmed the amorphous nature of paclitaxel and the fine dispersion of paclitaxel in the matrix of PVP-K30 and SLS. Furthermore, in vitro tests showed a major increase in the apparent solubility and dissolution rate of paclitaxel. To test the clinical significance of these findings, the solid dispersion formulation of paclitaxel (ModraPac001 10mg capsule) was compared to the paclitaxel premix solution in four patients with advanced cancer. Although the mean systemic exposure to paclitaxel after oral administration of the solid dispersion formulation was slightly lower compared to the paclitaxel premix solution (190±63.1ng/mLh for vs. 247±100ng/mLh), the systemic exposure to paclitaxel is clinically relevant [1,2]. In addition to this, the favorable pharmaceutical characteristics, for example, neutral taste, dosing accuracy, and the 2-year ambient shelf life, make the ModraPac001 10mg capsule an attractive candidate for oral paclitaxel chemotherapy. Currently, the ModraPac001 formulation is applied in the first clinical trial with oral LDM chemotherapy of paclitaxel. PMID:23085332

  14. Paclitaxel/beta-cyclodextrin complexes for hyperthermic peritoneal perfusion - formulation and stability.

    PubMed

    Bouquet, Wim; Ceelen, Wim; Fritzinger, Bernd; Pattyn, Piet; Peeters, Marc; Remon, Jean Paul; Vervaet, Chris

    2007-06-01

    Due to its low aqueous solubility paclitaxel is currently formulated in a Cremophor EL/ethanol mixture. However, the vehicle of this formulation causes several side-effects. Our objective was to formulate a tensioactive-free and solvent-free paclitaxel solution, which can be used for a hyperthermic intraperitoneal chemoperfusion procedure (HIPEC). The potential of chemically modified beta-cyclodextrins to form complexes with paclitaxel was investigated as a means to increase the aqueous solubility of paclitaxel. Methylated beta-CDs (randomly methylated and 2,6-dimethylated) showed the best ability to solubilise paclitaxel compared to sulfobutyl-ether- and hydroxypropyl-beta-CD. The minimal ratio of paclitaxel versus randomly methylated-beta-cyclodextrin (RAME-beta-CD) yielding 100% inclusion efficiency was 1/20 (mol/mol). Paclitaxel/RAME-beta-CD inclusion complexes prepared via freeze drying were stable for at least 6 months when stored at 4 degrees C. A 5mg/ml paclitaxel solution was formulated using paclitaxel/RAME-beta-CD-complexes. Upon dilution of these solutions, no precipitation was seen. After 24h storage at room temperature or 2h at HIPEC conditions (41.5 degrees C) the 1/40 (mol/mol) ratio showed the highest stability at paclitaxel concentrations of 0.1 and 0.5mg/ml. When hydroxypropyl methylcellulose (HPMC) was added to the reconstitution medium, the stability significantly increased, offering the opportunity to reduce the amount of RAME-beta-CDs in the formulation. PMID:17240125

  15. Pharmacokinetic drug interactions between apigenin, rutin and paclitaxel mediated by P-glycoprotein in rats.

    PubMed

    Kumar, K Kishore; Priyanka, Leena; Gnananath, K; Babu, P Ravindra; Sujatha, S

    2015-09-01

    The aim of present study was to investigate the effects of apigenin and rutin on the pharmacokinetics of paclitaxel after oral administration of paclitaxel with apigenin and rutin to rats. Paclitaxel (40 mg/kg) was administered orally alone and in combination with apigenin and rutin (10, 20, and 40 mg/kg) for 15 consecutive days. In the single-dose pharmacokinetic study (SDS), blood samples were collected on 1st day whereas on 15th day in the multiple-dose pharmacokinetic study (MDS). The plasma concentrations of paclitaxel were increased dose-dependently in the combination of apigenin and rutin compared to that of paclitaxel control in SDS and MDS (p < 0.01). The areas under the plasma concentration-time curve (AUC) and the plasma peak concentrations (C max) of paclitaxel with apigenin and rutin were significantly higher (p < 0.01) than that of the control. The AUCs and C max of paclitaxel were increased with apigenin and rutin in the dose-dependent manner. The half-life (t 1/2) was significantly longer than that of the control. Non-everted sacs were filled with paclitaxel 100 μM in the presence and absence of verapamil (50 μM), apigenin, and rutin (50, 100 μM) and incubated at 37 ºC for 60 min. The absorption of paclitaxel was increased in the presence of apigenin, rutin, and verapamil, a typical P-glycoprotein and Cyp3A4 inhibitor. If these results are confirmed in humans in a clinical setting, the paclitaxel dose should be adjusted when it is given concomitantly with apigenin and rutin. PMID:24871039

  16. Pharmacokinetics and pharmacodynamics of nab-paclitaxel in patients with solid tumors: Disposition kinetics and pharmacology distinct from solvent-based paclitaxel

    PubMed Central

    Chen, Nianhang; Li, Yan; Ye, Ying; Palmisano, Maria; Chopra, Rajesh; Zhou, Simon

    2014-01-01

    The aim of this study was to characterize population pharmacokinetics and the exposure–neutropenia relationship with nanoparticle albumin-bound (nab)-paclitaxel in patients with solid tumors. Plasma and blood concentrations of paclitaxel and neutrophil data were collected from 150 patients with various solid tumors over the nab-paclitaxel dose range of 80–375 mg/m2. Data were analyzed using nonlinear mixed-effect modeling or logistic regression. Pharmacokinetics of nab-paclitaxel were described by a 3-compartment model with saturable distribution and elimination. The rapid disappearance of circulating paclitaxel was driven by its fast distribution to peripheral compartments; maximum rate for saturable distribution (325000 μg/h) was 40-fold greater than that for saturable elimination (8070 μg/h). Albumin was a significant covariate of paclitaxel elimination (P < .001), while total bilirubin, creatinine clearance, body size, age, sex, and tumor type had no significant or clinically relevant effect. The probability of experiencing a ≥50% reduction in neutrophils was best correlated to the duration above the drug concentration of 720 ng/mL. At a given exposure level, neutropenia development was positively correlated with increasing age but not significantly influenced by hepatic function, tumor type, sex, or dosing schedule. Covariate analyses supports exposure-matched dose adjustments in patients with moderate to severe hepatic impairment. PMID:24719309

  17. Inhibition of Spleen Tyrosine Kinase Potentiates Paclitaxel-Induced Cytotoxicity in Ovarian Cancer Cells by Stabilizing Microtubules.

    PubMed

    Yu, Yu; Gaillard, Stephanie; Phillip, Jude M; Huang, Tai-Chung; Pinto, Sneha M; Tessarollo, Nayara G; Zhang, Zhen; Pandey, Akhilesh; Wirtz, Denis; Ayhan, Ayse; Davidson, Ben; Wang, Tian-Li; Shih, Ie-Ming

    2015-07-13

    Resistance to chemotherapy represents a major obstacle for long-term remission, and effective strategies to overcome drug resistance would have significant clinical impact. We report that recurrent ovarian carcinomas after paclitaxel/carboplatin treatment have higher levels of spleen tyrosine kinase (SYK) and phospho-SYK. In vitro, paclitaxel-resistant cells expressed higher SYK, and the ratio of phospho-SYK/SYK positively associated with paclitaxel resistance in ovarian cancer cells. Inactivation of SYK by inhibitors or gene knockdown sensitized paclitaxel cytotoxicity in vitro and in vivo. Analysis of the phosphotyrosine proteome in paclitaxel-resistant tumor cells revealed that SYK phosphorylates tubulins and microtubule-associated proteins. Inhibition of SYK enhanced microtubule stability in paclitaxel-resistant tumor cells that were otherwise insensitive. Thus, targeting SYK pathway is a promising strategy to enhance paclitaxel response. PMID:26096845

  18. Evolving Evidence of the Efficacy and Safety of nab-Paclitaxel in the Treatment of Cancers with Squamous Histologies

    PubMed Central

    Loong, Herbert H.; Chan, Alvita C.Y.; Wong, Ashley C.Y.

    2016-01-01

    Taxanes, such as paclitaxel and docetaxel, are well-established cytotoxic chemotherapeutics used in the treatment of a variety of cancers, including those of squamous histology. In their formulation, both agents require solvents, which have been associated with hypersensitivity reactions, peripheral neuropathy, hepatic toxicities, and impaired drug delivery. nab-Paclitaxel is a novel, albumin-bound form of paclitaxel with improved tolerability, bioavailability, and efficacy compared with solvent-based paclitaxel. Currently, nab-paclitaxel is approved for the treatment of metastatic breast cancer, locally advanced/metastatic non-small cell lung cancer (NSCLC), and metastatic pancreatic cancer. Clinical studies suggest that nab-paclitaxel may be particularly effective in cancers with squamous histology, including NSCLC. This article reviews the emerging evidence supporting nab-paclitaxel as an effective agent in the treatment of malignancies of squamous histology. PMID:26918039

  19. Loss of functional E-cadherin renders cells more resistant to the apoptotic agent taxol in vitro

    SciTech Connect

    Ferreira, Paulo; Oliveira, Maria Jose; Beraldi, Eliana; Mateus, Ana Rita; Nakajima, Takashi; Gleave, Martin; Yokota, Jun; Carneiro, Fatima; Huntsman, David; Seruca, Raquel; Suriano, Gianpaolo . E-mail: gsuriano@ipatimup.pt

    2005-10-15

    Experimental evidence supports a role for E-cadherin in suppressing invasion, metastasis, and proliferation. Germline mutations of the E-cadherin represent the genetic cause of hereditary diffuse gastric cancer (HDGC). In this type of tumor, isolated cancer cells permeate the basal membrane and paradoxically survive in the gastric wall in the absence of contact with neighbor epithelial cells or with the extracellular matrix. This suggests that upon E-cadherin deregulation, cells acquired resistance to apoptosis. To test this hypothesis, CHO cells stably expressing either wild-type E-cadherin or the HDGC-related germline mutations T340A and V832M were seeded either on a thin layer of collagen type I or on plastic and then subjected to the apoptotic agent taxol. We found that in vitro functional E-cadherin renders cells more sensitive to the effect of taxol. Our results also indicate that this effect is associated to decreased level of the anti-apoptotic bcl-2 protein.

  20. Chemotherapy Drugs Thiocolchicoside and Taxol Permeabilize Lipid Bilayer Membranes by Forming Ion Pores

    NASA Astrophysics Data System (ADS)

    Ashrafuzzaman, Md; Duszyk, M.; Tuszynski, J. A.

    2011-12-01

    We report ion channel formation by chemotherapy drugs: thiocolchicoside (TCC) and taxol (TXL) which primarily target tubulin but not only. For example, TCC has been shown to interact with GABAA, nuclear envelope and strychnine-sensitive glycine receptors. TXL interferes with the normal breakdown of microtubules inducing mitotic block and apoptosis. It also interacts with mitochondria and found significant chemotherapeutic applications for breast, ovarian and lung cancer. In order to better understand the mechanisms of TCC and TXL actions, we examined their effects on phospholipid bilayer membranes. Our electrophysiological recordings across membranes constructed in NaCl aqueous phases consisting of TCC or TXL under the influence of an applied transmembrane potential (V) indicate that both molecules induce stable ion flowing pores/channels in membranes. Their discrete current versus time plots exhibit triangular shapes which is consistent with a spontaneous time-dependent change of the pore conductance in contrast to rectangular conductance events usually induced by ion channels. These events exhibit conductance (~0.01-0.1 pA/mV) and lifetimes (~5-30 ms) within the ranges observed in e.g., gramicidin A and alamethicin channels. The channel formation probability increases linearly with TCC/TXL concentration and V and is not affected by pH (5.7 - 8.4). A theoretical explanation on the causes of chemotherapy drug induced ion pore formation and the pore stability has also been found using our recently discovered binding energy between lipid bilayer and the bilayer embedded ion channels using gramicidin A channels as tools. This picture of energetics suggests that as the channel forming agents approach to the lipids on bilayer the localized charge properties in the constituents of both channel forming agents (e.g., chemotherapy drugs in this study) and the lipids determine the electrostatic drug-lipid coupling energy through screened Coulomb interactions between the drug molecules and lipids. The strength of this electrostatic energetic coupling determines the stability of the drug-induced ion pores. These findings may elucidate cytotoxic effects of chemotherapy drugs and aid in the development of novel drugs for a broad spectrum of cancers and other diseases.

  1. Phase II and pharmacokinetic study of paclitaxel therapy for unresectable hepatocellular carcinoma patients.

    PubMed Central

    Chao, Y.; Chan, W. K.; Birkhofer, M. J.; Hu, O. Y.; Wang, S. S.; Huang, Y. S.; Liu, M.; Whang-Peng, J.; Chi, K. H.; Lui, W. Y.; Lee, S. D.

    1998-01-01

    Hepatocellular carcinoma (HCC) is a common lethal disease in Asia and there is no effective chemotherapy. Identification of new effective drugs in the treatment of inoperable HCC is urgently need. This is a phase II clinical study to investigate the efficacy, toxicity and pharmacokinetics of paclitaxel in HCC patients. Twenty patients with measurable, unresectable HCC, normal serum bilirubin, normal bone marrow and renal functions were studied. Paclitaxel 175 mg m(-2) was given intravenously over 3 h every 3 weeks. No complete or partial responses were observed. Five patients had stable disease. Major treatment toxicities (grade 3-4) were neutropenia (25%), thrombocytopenia (15%), infection (10%) and allergy (10%). Treatment-related deaths occurred in two patients. The median survival was 12 weeks (range 1-36). Paclitaxel is metabolized by the liver and the pharmacokinetics of paclitaxel in cancer patients with liver involvement or impairment may be important clinically. Pharmacokinetic study was completed in 13 HCC patients. The paclitaxel area under the curve was significantly increased (P < 0.02), clearance decreased (P < 0.02) and treatment-related deaths increased (P = 0.03) in patients with hepatic impairment. In conclusion, paclitaxel in this dose and schedule has no significant anti-cancer effect in HCC patients. Paclitaxel should be used with caution in cancer patients with liver impairment. PMID:9662247

  2. High energy shock waves (HESW) enhance paclitaxel cytotoxicity in MCF-7 cells.

    PubMed

    Frairia, Roberto; Catalano, Maria G; Fortunati, Nicoletta; Fazzari, Annamaria; Raineri, Mariangela; Berta, Laura

    2003-09-01

    High energy shock waves (HESW) produced by a piezoelectric generator were studied for their effect on human breast cancer cell (MCF-7) viability and sensitivity to paclitaxel. A dose-dependent impairment of cell viability was observed after HESW treatment (250-2000 shock waves, rate = 4/s, energy flux density = 0.25 mJ/mm2). Single treatment with shock waves produced no significant growth inhibition. Combined exposure to paclitaxel (ranging 0.1 nM to 20 microM) and shock waves (100, 500 and 1000 shots, respectively) resulted in a significant reduction of MCF-7 cell proliferation at day 3 after treatment in respect with cells treated with paclitaxel alone. Notably, a cell viability reduction of about 50% was obtained after combined treatment with HESW and 10 nM paclitaxel, in front of a reduction of only 40% using 10 microM paclitaxel alone. Moreover, an earlier induction as well as an enhancement of apoptotis was observed in cells subjected to combined treatment with shock waves and paclitaxel (200 nM; 20 microM). In conclusion, HESW can enhance paclitaxel cytotoxicity in MCF-7 cells, thus allowing the treatment with lower doses of drug. PMID:14531493

  3. Estimation of taxol influence on changes in tubulin and vimentin systems in K-562 and HL-60 cell lines by immunofluorescence microscopy.

    PubMed

    Grzanka, A; Grzanka, D; Orlikowska, M; Zuryn, A; Grzanka, A

    2005-01-01

    The cytoskeletal system may be considered as an additional pathway involved in process of apoptosis and can be promising target for development of new chemotherapies. The study describes alterations in the distribution of vimentin and tubulin in taxol treated K-562 and HL-60 cells in relation to apoptotic changes. K-562 and HL-60 cells were treated with taxol in a range of concentrations (0.02-10 microM) for 72 hours. Significant changes in distribution of studied proteins occurred in the range 2-10 microM of taxol. K-562 cells showed thin network of vimentin distributed throughout cells or collapsed on nucleus. There were also cells with bright aggregates remembering apoptotic bodies. HL-60 cells showed strong labeling of vimentin in the cytoplasm as well as at the site of apoptotic bodies. Vimentin collapsed on the nucleus, labeling at poles and along the major axis of the cell were also seen. K-562 and HL- 60 cells showed radial labeling of tubulin from the centre, aggregates at the surface and bundled microtubules. These findings indicate that alterations in expression of studied cytoskeletal proteins after treatment with taxol were dose-dependent and related with characteristic features of apoptosis. PMID:15875079

  4. Integrative transcriptomics-based identification of cryptic drivers of taxol-resistance genes in ovarian carcinoma cells: Analysis of the androgen receptor

    PubMed Central

    Lu, Hsing-Pang; Chang, Ting-Chang; Chao, Chuck C.-K.

    2015-01-01

    A systematic analysis of the genes involved in taxol resistance (txr) has never been performed. In the present study, we created txr ovarian carcinoma cell lines to identify the genes involved in chemoresistance. Transcriptome analysis revealed 1,194 overexpressed genes in txr cells. Among the upregulated genes, more than 12 cryptic transcription factors were identified using MetaCore analysis (including AR, C/EBPβ, ERα, HNF4α, c-Jun/AP-1, c-Myc, and SP-1). Notably, individual silencing of these transcription factors (except HNF4`)sensitized txr cells to taxol. The androgen receptor (AR) and its target genes were selected for further analysis. Silencing AR using RNA interference produced a 3-fold sensitization to taxol in txr cells, a response similar to that produced by silencing abcb1. AR silencing also downregulated the expression of prominent txr gene candidates (including abcb1, abcb6, abcg2, bmp5, fat3, fgfr2, h1f0, srcrb4d, and tmprss15). In contrast, AR activation using the agonist DHT upregulated expression of the target genes. Individually silencing seven out of nine (78%) AR-regulated txr genes sensitized txr cells to taxol. Inhibition of AKT and JNK cellular kinases using chemical inhibitors caused a dramatic suppression of AR expression. These results indicate that the AR represents a critical driver of gene expression involved in txr. PMID:26318424

  5. Adverse drug reaction profile of nanoparticle versus conventional formulation of paclitaxel: An observational study

    PubMed Central

    Brahmachari, Ballari; Hazra, Avijit; Majumdar, Anup

    2011-01-01

    Objectives: Conventional polyethoxylated castor oil (PCO)-based paclitaxel is associated with major adverse drug reactions (ADRs). Nanoxel, a nanoparticle-based formulation, may improve its tolerability by removing the need for PCO vehicle, and also permit its use in a higher dose. We conducted intensive monitoring of the ADR profile of Nanoxel in comparison with conventional paclitaxel in a public tertiary care set-up. Materials and Methods: ADR data were collected from 10 patients receiving Nanoxel and 10 age-matched controls receiving conventional paclitaxel in this longitudinal observational study, conducted in a medical oncology ward over 18 months. Severity was graded as per US National Cancer Institute Common Terminology Criteria for Adverse Events. Results: The groups had comparable demography at baseline. The median disease duration and per cycle median dose of paclitaxel were greater in the Nanoxel arm. Total 119 ADRs were noted with Nanoxel and 123 with conventional paclitaxel. Of these, 25 (21.0%, 95% CI 13.69–28.33%) in the Nanoxel and 20 (16.2%, 95% CI 9.74–22.78%) in paclitaxel group were of grade 3/4 severity. Common events included myalgia, nausea, anemia, paresthesia, alopecia, diarrhea, and vomiting with Nanoxel, and paresthesia, anemia, myalgia, anorexia, alopecia, vomiting, diarrhea, stomatitis, and nausea with paclitaxel. Of the less common events (<5%), grade 2 or 3 arthralgia was seen exclusively with Nanoxel while motor neuropathy with muscular weakness was more frequent and severe with conventional paclitaxel. Hypersensitivity reactions were not encountered in either arm, although no antiallergy premedication was employed for Nanoxel. Conclusions: Despite its ADR profile being statistically comparable to conventional paclitaxel, this observational study suggests that Nanoxel tolerability could be better, considering that a significantly higher dose was employed. This hypothesis needs confirmation through an interventional study. PMID:21572644

  6. Prostate cancer cell response to paclitaxel is affected by abnormally expressed securin PTTG1.

    PubMed

    Castilla, Carolina; Flores, M Luz; Medina, Rafael; Pérez-Valderrama, Begoña; Romero, Francisco; Tortolero, María; Japón, Miguel A; Sáez, Carmen

    2014-10-01

    PTTG1 protein, the human securin, has a central role in sister chromatid separation during mitosis, and its altered expression has been reported in many tumor types. Paclitaxel is a widely used chemotherapeutic drug, whose mechanism of action is related to its ability to arrest cells in mitosis and the subsequent induction of the intrinsic apoptotic pathway. By using two prostate cancer cell lines with different responses to paclitaxel treatment, we have identified two situations in which PTTG1 influences cell fate differentially. In slippage-prone PC3 cells, both PTTG1 downregulation and overexpression induce an increase in mitotic cells that is associated with diminished apoptosis after paclitaxel treatment. In LNCaP cells, however, PTTG1 downregulation prevents mitotic entry and, subsequently, inhibits mitosis-associated, paclitaxel-induced apoptosis. In contrast, PTTG1 overexpression induces an increase in mitotic cells and apoptosis after paclitaxel treatment. We have also identified a role for Mcl-1 protein in preventing apoptosis during mitosis in PC3 cells, as simultaneous PTTG1 and Mcl-1 silencing enhances mitosis-associated apoptosis after paclitaxel treatment. The finding that a more efficient mitotic arrest alone in PC3 cells is not enough to increase apoptosis was also confirmed with the observation that a selected paclitaxel-resistant PC3 cell line showed an apoptosis-resistant phenotype associated with increased mitosis upon paclitaxel treatment. These findings could contribute to identify putative responsive and nonresponsive cells and help us to approach incomplete responses to paclitaxel in the clinical setting. PMID:25122070

  7. Preparation, characterization, and efficacy of thermosensitive liposomes containing paclitaxel.

    PubMed

    Wang, Zhi-Yuan; Zhang, Hui; Yang, Yang; Xie, Xiang-Yang; Yang, Yan-Fang; Li, Zhiping; Li, Ying; Gong, Wei; Yu, Fang-Lin; Yang, Zhenbo; Li, Ming-Yuan; Mei, Xing-Guo

    2016-05-01

    To increase the anti-tumor activity of paclitaxel (PTX), novel temperature-sensitive liposomes loading paclitaxel (PTX-TSL) were developed. In vitro, characteristics of PTX-TSL were evaluated. The mean particle diameter was about 100 nm, and the entrapment efficiency was larger than 95%. The phase-transition temperature of PTX-TSL determined by differential scanning calorimetry was about 42 °C. The result of in vitro drug release from PTX-TSL illustrated that release rate at 37 °C was obviously lower than that at 42 °C. Stability data indicated that the liposome was physically and chemically stable for at least 3 months at -20 °C. In vivo study, after three injections with hyperthermia in the xenograft lung tumor model, PTX-TSL showed distinguished tumor growth suppression, compared with non-temperature-sensitive liposome and free drug. The results of intratumoral drug concentration indicated that PTX-TSL combined with hyperthermia delivered more paxlitaxel into the tumor location than the other two paxlitaxel formulations. In summary, PTX-TSL combined with hyperthermia significantly inhibited tumor growth, due to the increased targeting efficiency of PTX to tumor tissues. Such approach may enhance the delivery efficiency of chemotherapeutics into solid tumors. PMID:26666408

  8. Paclitaxel loaded PEGylated gleceryl monooleate based nanoparticulate carriers in chemotherapy.

    PubMed

    Jain, Vikas; Swarnakar, Nitin K; Mishra, Prabhat R; Verma, Ashwni; Kaul, Ankur; Mishra, Anil K; Jain, Narendra K

    2012-10-01

    A PEGylated drug delivery system of paclitaxel (PTX), based on glyceryl monooleate (GMO) was prepared by optimizing various parameters to explore its potential in anticancer therapy. The prepared system was characterized through polarized light microscopy, TEM, AFM and SAXS to reveal its liquid crystalline nature. As GMO based LCNPs exhibit high hemolytic toxicity and faster release of entrapped drug (66.2 ± 2.5% in 24 h), PEGylation strategy was utilized to increase the hemocompatibility (reduction in hemolysis from 60.3 ± 10.2 to 4.4 ± 1.3%) and control the release of PTX (43.6 ± 3.2% released in 24 h). The cytotoxic potential and cellular uptake was assessed in MCF-7 cell lines. Further, biodistribution studies were carried out in EAT (Ehrlich Ascites tumor) bearing mice using (99m)Tc-(Technetium radionuclide) labeled formulations and an enhanced circulation time and tumor accumulation (14 and 8 times, respectively) were observed with PEGylated carriers over plain ones, at 24 h. Finally, tumor growth inhibition experiment was performed and after 15 days, control group exhibited 15 times enhancement in tumor volume, while plain and PEGylated systems exhibited only 8 and 4 times enhancement, respectively, as compared to initial tumor volume. The results suggest that PEGylation enhances the hemocompatibility and efficacy of GMO based system that may serve as an efficient i.v. delivery vehicle for paclitaxel. PMID:22809646

  9. Doxorubicin and paclitaxel loaded microbubbles for ultrasound triggered drug delivery

    PubMed Central

    Cochran, Michael C.; Eisenbrey, John; Ouma, Richard O.; Soulen, Michael; Wheatley, Margaret A.

    2011-01-01

    A polymer ultrasound contrast agent (UCA) developed in our lab has been shown to greatly reduce in size when exposed to ultrasound, resulting in nanoparticles less than 400 nm in diameter capable of escaping the leaky vasculature of a tumor to provide a sustained release of drug. Previous studies with the hydrophilic drug doxorubicin (DOX) demonstrated enhanced drug delivery to tumors when triggered with ultrasound. However the therapeutic potential has been limited due to the relatively low payload of DOX. This study compares the effects of loading the hydrophobic drug paclitaxel (PTX) on the agent’s acoustic properties, drug payload, tumoricidal activity, and the ability to deliver drugs through 400 nm pores. A maximum payload of 129.46 ± 1.80 μg PTX/mg UCA (encapsulation efficiency 71.92 ± 0.99 %) was achieved, 20 times greater than the maximum payload of DOX (6.2 μg/mg), while maintaining the acoustic properties. In vitro, the tumoricidal activity of paclitaxel loaded UCA exposed to ultrasound was significantly greater than controls not exposed to ultrasound (p<0.0016). This study has shown that PTX loaded UCA triggered with focused ultrasound have the potential to provide a targeted and sustained delivery of drug to tumors. PMID:21609756

  10. Nanoparticle Albumin Bound Paclitaxel in the Treatment of Human Cancer: Nanodelivery Reaches Prime-Time?

    PubMed Central

    Cucinotto, Iole; Fiorillo, Lucia; Gualtieri, Simona; Arbitrio, Mariamena; Ciliberto, Domenico; Staropoli, Nicoletta; Grimaldi, Anna; Luce, Amalia; Tassone, Pierfrancesco; Caraglia, Michele; Tagliaferri, Pierosandro

    2013-01-01

    Nanoparticle albumin bound paclitaxel (nab-paclitaxel) represents the first nanotechnology-based drug in cancer treatment. We discuss the development of this innovative compound and report the recent changing-practice results in breast and pancreatic cancer. A ground-breaking finding is the demonstration that nab-paclitaxel can not only enhance the activity and reduce the toxicity of chromophore-diluted compound, but also exert activity in diseases considered refractory to taxane-based treatment. This is the first clinical demonstration of major activity of nanotechnologically modified drugs in the treatment of human neoplasms. PMID:23738077

  11. Nanoparticle albumin bound Paclitaxel in the treatment of human cancer: nanodelivery reaches prime-time?

    PubMed

    Cucinotto, Iole; Fiorillo, Lucia; Gualtieri, Simona; Arbitrio, Mariamena; Ciliberto, Domenico; Staropoli, Nicoletta; Grimaldi, Anna; Luce, Amalia; Tassone, Pierfrancesco; Caraglia, Michele; Tagliaferri, Pierosandro

    2013-01-01

    Nanoparticle albumin bound paclitaxel (nab-paclitaxel) represents the first nanotechnology-based drug in cancer treatment. We discuss the development of this innovative compound and report the recent changing-practice results in breast and pancreatic cancer. A ground-breaking finding is the demonstration that nab-paclitaxel can not only enhance the activity and reduce the toxicity of chromophore-diluted compound, but also exert activity in diseases considered refractory to taxane-based treatment. This is the first clinical demonstration of major activity of nanotechnologically modified drugs in the treatment of human neoplasms. PMID:23738077

  12. Promotion of mitotic catastrophe via activation of PTEN by paclitaxel with supplement of mulberry water extract in bladder cancer cells

    PubMed Central

    Chen, Nien-Cheng; Chyau, Charng-Cherng; Lee, Yi-Ju; Tseng, Hsien-Chun; Chou, Fen-Pi

    2016-01-01

    Paclitaxel is a mitotic inhibitor used in cancer chemotherapy. Mulberry fruit is rich in phenolic compounds and flavonoids and exhibits chemopreventive activities. In this study, mulberry water extract (MWE) was used as a supplement to synergize with the effects of paclitaxel in the treatment of the TSGH 8301 human bladder cancer cell line. Treatment with paclitaxel combined with MWE (paclitaxel/MWE) enhanced the cytotoxicity of paclitaxel and induced severe G2/M arrest, mitotic catastrophe and subsequent apoptosis, as shown by MTT assay, HE staining and flow cytometry analyses. Differences in the expression and activation of Aurora A and Plk1between cells treated with paclitaxel/MWE and paclitaxel alone suggested that the combined treatment caused a defect in the early steps of cytokinesis. Paclitaxel/MWE decreased EEA1immunofluorescence staining and increased the expression of PTEN, indicating that the regimen inhibited the formation of the recycling endosome, which is required for cytokinesis. Paclitaxel/MWE also retarded tumor growth in a TSGH 8301 xenograft model via activation of PTEN and Caspase 3. These data demonstrated a synergistic effect on the anticancer efficacy of paclitaxel through MWE supplementation by promoting mitotic catastrophe through the activation of PTEN, providing a novel and effective therapeutic option for bladder cancer treatment strategies. PMID:26838546

  13. Promotion of mitotic catastrophe via activation of PTEN by paclitaxel with supplement of mulberry water extract in bladder cancer cells.

    PubMed

    Chen, Nien-Cheng; Chyau, Charng-Cherng; Lee, Yi-Ju; Tseng, Hsien-Chun; Chou, Fen-Pi

    2016-01-01

    Paclitaxel is a mitotic inhibitor used in cancer chemotherapy. Mulberry fruit is rich in phenolic compounds and flavonoids and exhibits chemopreventive activities. In this study, mulberry water extract (MWE) was used as a supplement to synergize with the effects of paclitaxel in the treatment of the TSGH 8301 human bladder cancer cell line. Treatment with paclitaxel combined with MWE (paclitaxel/MWE) enhanced the cytotoxicity of paclitaxel and induced severe G2/M arrest, mitotic catastrophe and subsequent apoptosis, as shown by MTT assay, HE staining and flow cytometry analyses. Differences in the expression and activation of Aurora A and Plk1between cells treated with paclitaxel/MWE and paclitaxel alone suggested that the combined treatment caused a defect in the early steps of cytokinesis. Paclitaxel/MWE decreased EEA1immunofluorescence staining and increased the expression of PTEN, indicating that the regimen inhibited the formation of the recycling endosome, which is required for cytokinesis. Paclitaxel/MWE also retarded tumor growth in a TSGH 8301 xenograft model via activation of PTEN and Caspase 3. These data demonstrated a synergistic effect on the anticancer efficacy of paclitaxel through MWE supplementation by promoting mitotic catastrophe through the activation of PTEN, providing a novel and effective therapeutic option for bladder cancer treatment strategies. PMID:26838546

  14. Paclitaxel Induces Apoptosis in Breast Cancer Cells through Different Calcium—Regulating Mechanisms Depending on External Calcium Conditions

    PubMed Central

    Pan, Zhi; Avila, Andrew; Gollahon, Lauren

    2014-01-01

    Previously, we reported that endoplasmic reticulum calcium stores were a direct target for paclitaxel initiation of apoptosis. Furthermore, the actions of paclitaxel attenuated Bcl-2 resistance to apoptosis through endoplasmic reticulum-mediated calcium release. To better understand the calcium-regulated mechanisms of paclitaxel-induced apoptosis in breast cancer cells, we investigated the role of extracellular calcium, specifically; whether influx of extracellular calcium contributed to and/or was necessary for paclitaxel-induced apoptosis. Our results demonstrated that paclitaxel induced extracellular calcium influx. This mobilization of extracellular calcium contributed to subsequent cytosolic calcium elevation differently, depending on dosage. Under normal extracellular calcium conditions, high dose paclitaxel induced apoptosis-promoting calcium influx, which did not occur in calcium-free conditions. In the absence of extracellular calcium an “Enhanced Calcium Efflux” mechanism in which high dose paclitaxel stimulated calcium efflux immediately, leading to dramatic cytosolic calcium decrease, was observed. In the absence of extracellular calcium, high dose paclitaxel’s stimulatory effects on capacitative calcium entry and apoptosis could not be completely restored. Thus, normal extracellular calcium concentrations are critical for high dose paclitaxel-induced apoptosis. In contrast, low dose paclitaxel mirrored controls, indicating that it occurs independent of extracellular calcium. Thus, extracellular calcium conditions only affect efficacy of high dose paclitaxel-induced apoptosis. PMID:24549172

  15. Paclitaxel injection concentrate for nanodispersion versus nab-paclitaxel in women with metastatic breast cancer: a multicenter, randomized, comparative phase II/III study.

    PubMed

    Jain, Minish M; Gupte, Smita U; Patil, Shekhar G; Pathak, Anand B; Deshmukh, Chetan D; Bhatt, Niraj; Haritha, Chiramana; Govind Babu, K; Bondarde, Shailesh A; Digumarti, Raghunadharao; Bajpai, Jyoti; Kumar, Ravi; Bakshi, Ashish V; Bhattacharya, Gouri Sankar; Patil, Poonam; Subramanian, Sundaram; Vaid, Ashok K; Desai, Chirag J; Khopade, Ajay; Chimote, Geetanjali; Bapsy, Poonamalle P; Bhowmik, Shravanti

    2016-02-01

    Paclitaxel is widely used in the treatment of patients with metastatic breast cancer (MBC). Formulations of paclitaxel contain surfactants and solvents or albumin derived from human blood. The use of co-solvents such as polyoxyethylated castor oil is thought to contribute to toxicity profile and hypersensitivity reactions as well as leaching of plasticizers from polyvinyl chloride bags and infusion sets. Currently, nab-paclitaxel, an albumin-bound paclitaxel in nanometer range continues to be the preferred taxane formulation used in clinic. This study (CTRI/2010/091/001116) investigated the efficacy and tolerability of a polyoxyethylated castor oil- and albumin-free formulation of paclitaxel [paclitaxel injection concentrate for nanodispersion (PICN)] compared with nab-paclitaxel in women with refractory MBC. The current study was a multicenter, open-label, parallel-group, randomized, comparative phase II/III trial evaluating the efficacy and safety of PICN (260 mg/m(2) [n = 64] and 295 mg/m(2) [n = 58] every 3 weeks) compared with nab-paclitaxel (260 mg/m(2) every 3 weeks [n = 58]) in women 18 and 70 years old with confirmed MBC. Overall response rate (ORR) was assessed with imaging every 2 cycles. An independent analysis of radiologic data was performed for evaluable patients. Progression-free survival (PFS) was a secondary efficacy measure. Independent radiologist-assessed ORRs in the evaluable population of women aged ≥70 years were 35, 49, and 43 % in the PICN 260 mg/m(2), PICN 295 mg/m(2), and nab-paclitaxel 260 mg/m(2) arms, respectively. Median PFS in the evaluable population was 23, 35, and 34 weeks in the PICN 260 mg/m(2), PICN 295 mg/m(2), and nab-paclitaxel 260 mg/m(2) arms, respectively. Adverse events occurred in similar proportions of patients across treatment arms. Hypersensitivity reactions were not frequently observed with the clinical use of PICN across the treatment cohorts. In women with metastatic breast cancer, PICN at 260 and 295 mg/m(2) every 3 weeks was effective and well tolerated and showed similar tolerability compared with nab-paclitaxel 260 mg/m(2) every 3 weeks. Statistically, significant differences were not observed in the PICN and nab-paclitaxel treatment arms for radiologist-assessed ORR or median PFS. The novel paclitaxel formulation, PICN, offers apart from efficacy, potential safety advantage of decreased use of corticosteroid pretreatment and the absence of the risk of transmission of blood product-borne disease. PMID:26941199

  16. Poly-cyclodextrin and poly-paclitaxel nano-assembly for anticancer therapy

    NASA Astrophysics Data System (ADS)

    Namgung, Ran; Mi Lee, Yeong; Kim, Jihoon; Jang, Yuna; Lee, Byung-Heon; Kim, In-San; Sokkar, Pandian; Rhee, Young Min; Hoffman, Allan S.; Kim, Won Jong

    2014-05-01

    Effective anticancer therapy can be achieved by designing a targeted drug-delivery system with high stability during circulation and efficient uptake by the target tumour cancer cells. We report here a novel nano-assembled drug-delivery system, formed by multivalent host-guest interactions between a polymer-cyclodextrin conjugate and a polymer-paclitaxel conjugate. The multivalent inclusion complexes confer high stability to the nano-assembly, which efficiently delivers paclitaxel into the targeted cancer cells via both passive and active targeting mechanisms. The ester linkages between paclitaxel and the polymer backbone permit efficient release of paclitaxel within the cell by degradation. This novel targeted nano-assembly exhibits significant antitumour activity in a mouse tumour model. The strategy established in this study also provides knowledge for the development of advanced anticancer drug delivery.

  17. Effect of genistein on the pharmacokinetics of paclitaxel administered orally or intravenously in rats.

    PubMed

    Li, Xiuguo; Choi, Jun-Shik

    2007-06-01

    As many anticancer agents paclitaxel is a substrate for ATP-binding cassette (ABC) transporters such as P-glycoprotein-mediated efflux, and its metabolism in humans mainly catalyzed by CYP 3A4 and 2C8. Genistein, an isoflavonoid, is supposed to be an inhibitor of some ABC transporters, and its oxidative metobolism catalyzed by CYP 3A4 and 2C8. The purpose of this study was to investigate the effect of orally administered genistein on the pharmacokinetics of paclitaxel administered through oral and intravenous (i.v.) route in rats. A single dose of paclitaxel administered orally (30 mg/kg) or i.v. (3mg/kg) alone or 30 min after oral administration of genistein (3.3mg/kg or 10mg/kg). The presence of 10mg/kg genistein significantly (p<0.05) increased the area under the plasma concentration-time curve (AUC, 54.7% greater) of orally administered paclitaxel, which was due to the significantly (p<0.05) decreased total plasma clearance (CL/F) of paclitaxel (35.2% lower). Genistein also increased the peak concentration (C(max)) of paclitaxel significantly (p<0.05 by 3.3mg/kg, 66.8% higher; p<0.01 by 10mg/kg, 91.8% higher). Consequently, the absolute bioavailability (F) of paclitaxel in the presence of genistein was 0.020-0.025, which was elevated more than the control group (0.016); and the relative bioavailability (Fr) of orally administered paclitaxel was increased from 1.26- to 1.55-fold. Ten milligrams per kilogram genistein also significantly (p<0.05) increased the AUC (40.5% greater) and reduced the total clearance (CLt, 30% lower) of i.v. administered paclitaxel. The presence of genistein improved the systemic exposure of paclitaxel in this study. The pharmacokinetic interaction between them should be taken into consideration when paclitaxel is used with genistein or the dietary supplements full of genistein. PMID:17267149

  18. Cardioprotective effect of royal jelly on paclitaxel-induced cardio-toxicity in rats

    PubMed Central

    Malekinejad, Hassan; Ahsan, Sima; Delkhosh-Kasmaie, Fatemeh; Cheraghi, Hadi; Rezaei-Golmisheh, Ali; Janbaz-Acyabar, Hamed

    2016-01-01

    Objective(s): Paclitaxel is a potent chemotherapy agent with severe side effects, including allergic reactions, cardiovascular problems, complete hair loss, joint and muscle pain, which may limit its use and lower its efficiency. The cardioprotective effect of royal jelly was investigated on paclitaxel-induced damages. Materials and Methods: Adult male Wistar rats were divided into control and test groups (n=8). The test group was assigned into five subgroups; 4 groups, along with paclitaxel administration (7.5 mg/kg BW, weekly), received various doses of royal jelly (50, 100, and 150 mg/kg BW) for 28 consecutive days. The last group received only royal jelly at 100 mg/kg. In addition to oxidative and nitrosative stress biomarkers, the creatine kinase (CK-BM) level was also determined. To show the cardioprotective effect of royal jelly on paclitaxel-induced damages, histopathological examinations were conducted. Results: Royal jelly lowered the paclitaxel-elevated malondialdehyde and nitric oxide levels in the heart. Royal jelly could also remarkably reduce the paclitaxel-induced cardiac biomarker of creatine kinase (CK-BM) level and pathological injuries such as diffused edema, hemorrhage, congestion, hyaline exudates, and necrosis. Moreover, royal jelly administration in a dose-dependent manner resulted in a significant (P<0.05) increase in the paclitaxel-reduced total antioxidant capacity. Conclusion: Our data suggest that the paclitaxel-induced histopathological and biochemical alterations could be protected by the royal jelly administration. The cardioprotective effect of royal jelly may be related to the suppression of oxidative and nitrosative stress. PMID:27081469

  19. Synergy of a Herpes OncolyticVirus and Paclitaxel for Anaplastic Thyroid Cancer

    PubMed Central

    Lin, Shu-Fu; Gao, Sizhi Paul; Price, Daniel L.; Li, Sen; Chou, Ting-Chao; Singh, Paramjeet; Huang, Yu-Yao; Fong, Yuman; Wong, Richard J.

    2009-01-01

    Purpose Novel therapeutic regimens are needed to improve the dismal outcomes of patients with anaplastic thyroid cancer (ATC). Oncolytic herpes simplex virus have shown promising activity against human ATC. We studied the application of oncolytic herpes simplex virus (G207 and NV1023) in combination with currently used chemotherapeutic drugs (paclitaxel and doxorubicin) for the treatment of ATC. Experimental Design and Results All four agents showed dose-response cytotoxicity in vitro for the human ATC cell lines KAT4 and DRO90-1. G207, combined with paclitaxel, showed synergistic cytotoxicity. Chou-Talalay combination indices ranged from 0.56 to 0.66 for KAT4, and 0.68 to 0.74 for DRO90-1at higher affected fractions. Paclitaxel did not enhance G207 viral entry and early gene expression or G207 viral replication. Paclitaxel combined with G207 compared with single-agent treatment or controls showed significantly increased microtubule acetylation, mitotic arrest, aberrant chromatid separation, inhibition of metaphase to anaphase progression, and apoptosis. A single i.t. injection of G207 combined with biweekly i.p. paclitaxel injections in athymic nude mice bearing KAT4 flank tumors showed significantly reduced mean tumor volume (74 F 38 mm3) compared with G207 alone (388 F 109 mm3), paclitaxel alone (439 F 137 mm3), and control (520 F 160 mm3) groups at 16 days. There was no morbidity in vivo attributable to therapy. Conclusions Mechanisms of paclitaxel antitumoral activity, including microtubule acetylation, mitotic block, and apoptosis, were enhanced by G207, which also has direct oncolytic effects. Combination of G207 and paclitaxel therapy is synergistic in treating ATC and holds promise for patients with this fatal disease. PMID:18316577

  20. Genomic signatures for paclitaxel and gemcitabine resistance in breast cancer derived by machine learning.

    PubMed

    Dorman, Stephanie N; Baranova, Katherina; Knoll, Joan H M; Urquhart, Brad L; Mariani, Gabriella; Carcangiu, Maria Luisa; Rogan, Peter K

    2016-01-01

    Increasingly, the effectiveness of adjuvant chemotherapy agents for breast cancer has been related to changes in the genomic profile of tumors. We investigated correspondence between growth inhibitory concentrations of paclitaxel and gemcitabine (GI50) and gene copy number, mutation, and expression first in breast cancer cell lines and then in patients. Genes encoding direct targets of these drugs, metabolizing enzymes, transporters, and those previously associated with chemoresistance to paclitaxel (n = 31 genes) or gemcitabine (n = 18) were analyzed. A multi-factorial, principal component analysis (MFA) indicated expression was the strongest indicator of sensitivity for paclitaxel, and copy number and expression were informative for gemcitabine. The factors were combined using support vector machines (SVM). Expression of 15 genes (ABCC10, BCL2, BCL2L1, BIRC5, BMF, FGF2, FN1, MAP4, MAPT, NFKB2, SLCO1B3, TLR6, TMEM243, TWIST1, and CSAG2) predicted cell line sensitivity to paclitaxel with 82% accuracy. Copy number profiles of 3 genes (ABCC10, NT5C, TYMS) together with expression of 7 genes (ABCB1, ABCC10, CMPK1, DCTD, NME1, RRM1, RRM2B), predicted gemcitabine response with 85% accuracy. Expression and copy number studies of two independent sets of patients with known responses were then analyzed with these models. These included tumor blocks from 21 patients that were treated with both paclitaxel and gemcitabine, and 319 patients on paclitaxel and anthracycline therapy. A new paclitaxel SVM was derived from an 11-gene subset since data for 4 of the original genes was unavailable. The accuracy of this SVM was similar in cell lines and tumor blocks (70-71%). The gemcitabine SVM exhibited 62% prediction accuracy for the tumor blocks due to the presence of samples with poor nucleic acid integrity. Nevertheless, the paclitaxel SVM predicted sensitivity in 84% of patients with no or minimal residual disease. PMID:26372358

  1. Prevention of Paclitaxel-Induced Neuropathy Through Activation of the Central Cannabinoid Type 2 Receptor System

    PubMed Central

    Naguib, Mohamed; Xu, Jijun J.; Diaz, Philippe; Brown, David L.; Cogdell, David; Bie, Bihua; Hu, Jianhua; Craig, Suzanne; Hittelman, Walter N.

    2012-01-01

    Background Peripheral neuropathy is a major dose-limiting toxicity of chemotherapy, especially after multiple courses of paclitaxel. The development of paclitaxel-induced neuropathy is associated with the activation of microglia followed by the activation and proliferation of astrocytes, and the expression and release of proinflammatory cytokines in the spinal dorsal horn. Cannabinoid type 2 (CB2) receptors are expressed in the microglia in neurodegenerative disease models. Methods To explore the potential of CB2 agonists for preventing paclitaxel-induced neuropathy, we designed and synthesized a novel CB2-selective agonist, namely MDA7. The effect of MDA7 in preventing paclitaxel-induced allodynia was assessed in rats and in CB2+/+ and CB2–/– mice. We hypothesize that the CB2 receptor functions in a negative-feedback loop and that early MDA7 administration can blunt the neuroinflammatory response to paclitaxel and prevent mechanical allodynia through interference with specific signaling pathways. Results We found that MDA7 prevents paclitaxel-induced mechanical allodynia in rats and mice in a dose- and time-dependent manner without compromising paclitaxel's antineoplastic effect. MDA7's neuroprotective effect was absent in CB2-/- mice and was blocked by CB2 antagonists, suggesting that MDA7's action directly involves CB2 receptor activation. MDA7 treatment was found to interfere with early events in the paclitaxel-induced neuroinflammatory response as evidenced by relatively reduced Toll-like receptor and CB2 expression in the lumbar spinal cord, reduced levels of extracellular signal regulated kinase 1/2 activity, reduced numbers of activated microglia and astrocytes, and reduced secretion of proinflammatory mediators in vivo and in in vitro models. Conclusions Our findings suggest an innovative therapeutic approach to prevent chemotherapy-induced neuropathy and may permit more aggressive use of active chemotherapeutic regimens with reduced long-term sequelae. PMID:22392969

  2. Effect of Paclitaxel on Antitumor Activity of Cyclophosphamide: Study on Two Transplanted Tumors in Mice.

    PubMed

    Kaledin, V I; Nikolin, V P; Popova, N A; Pyshnaya, I A; Bogdanova, L A; Morozkova, T S

    2015-11-01

    Antitumor effect of paclitaxel used as the monotherapy or in combination with cyclophosphamide was studied on CBA/LacSto mice with transplanted LS and RLS tumors characterized by high (LS) and low (RLS) sensitivity to cyclophosphamide. The therapeutic effects of cyclophosphamide and paclitaxel were summed in animals with drug-resistant RLS tumor, while combined use of these drugs in LS tumor highly sensitive to the apoptogenic effect of cyclophosphamide was no more effective than cyclophosphamide alone. PMID:26597686

  3. Cost-Benefit Analysis of Nanoparticle Albumin-Bound Paclitaxel versus Solvent-Based Paclitaxel for the Treatment of Metastatic Breast Cancer in the United States

    NASA Astrophysics Data System (ADS)

    Vichansavakul, Kittaya

    Breast cancer is the second leading cause of death among women in the US. Although early detection and treatment help to increase survival rates, some unfortunate patients develop metastatic breast cancer that has no cure. Palliative treatment is the main objective in this group of patients in order to prolong life and reduce toxicities from interventions. In the advancement of treatment for metastatic breast cancer, solvent-based paclitaxel has been widely used. However, solvent-based paclitaxel often causes adverse reactions. Therefore, researchers have developed a new chemotherapy based on nanotechnology. One of these drugs is the Nanoparticle albumin-bound Paclitaxel. This nanodrug aims to increase therapeutic index by reducing adverse reactions from solvents and to improve efficacy of conventional cytotoxic chemotherapy. Breast cancer is a disease with high epidemiological and economic burden. The treatment of metastatic breast cancer has not only high direct costs but also high indirect costs. Breast cancer affects mass populations, especially women younger than 50 years of age. It relates to high indirect costs due to lost productivity and premature death because the majority of these patients are in the workforce. Because of the high cost of breast cancer therapies and short survival rates, the question is raised whether the costs and benefits are worth paying or not. Due to the rising costs in healthcare and new financing policies that have been developed to address this issue, economic evaluation is an important aspect of the development and use of any new interventions. To guide policy makers on how to allocate limited healthcare resources in the most efficient and effective manner, many economic evaluation methods can be used to measure the costs, benefits, and impacts of healthcare innovations. Currently, economic evaluation and health outcomes studies have focused greatly on cost-effectiveness and cost-utility analysis. However, the previous studies had some limitations because they were conducted from a narrow perspective such as payer and provider point of views. The studies also considered only direct costs in their analysis. In fact, conducting economic evaluations from a narrow perspective and leaving out indirect costs might undermine the true benefit of the interventions for society. A cost-benefit analysis measures all costs and benefits in monetary units. It incorporates both health outcomes gained from individuals and the value gained to society in order to maximize the usage of resources effectively. This thesis conducted a cost-benefit analysis to compare nab-paclitaxel and generic paclitaxel in treating metastatic breast cancer from a societal perspective in the United States. The results showed that nab-paclitaxel is a cost-benefit strategy regardless of the different costs and benefits due to the extra 3 years of living it provides. In all models, when nab-paclitaxel was compared to generic paclitaxel, nab-paclitaxel showed cost-benefit to society. However, the results of generic paclitaxel were dependent on the total medical costs. Performing a cost-benefit analysis of nab-paclitaxel from a societal perspective is important to understand the true benefit of interventions. Furthermore, considering both direct and indirect costs, as well as benefits, of this drug is vital because the economic profile of nab-paclitaxel would be improved.

  4. Nanosuspension delivery of paclitaxel to xenograft mice can alter drug disposition and anti-tumor activity

    PubMed Central

    2014-01-01

    Paclitaxel is a common chemotherapeutic agent that is effective against various cancers. The poor aqueous solubility of paclitaxel necessitates a large percentage of Cremophor EL:ethanol (USP) in its commercial formulation which leads to hypersensitivity reactions in patients. We evaluate the use of a crystalline nanosuspension versus the USP formulation to deliver paclitaxel to tumor-bearing xenograft mice. Anti-tumor efficacy was assessed following intravenous administration of three 20 mg/kg doses of paclitaxel. Paclitaxel pharmacokinetics and tissue distribution were evaluated, and differences were observed between the two formulations. Plasma clearance and tissue to plasma ratio of mice that were dosed with the nanosuspension are approximately 33- and 11-fold higher compared to those of mice that were given the USP formulation. Despite a higher tumor to plasma ratio for the nanosuspension treatment group, absolute paclitaxel tumor exposure was higher for the USP group. Accordingly, a higher anti-tumor effect was observed in the xenograft mice that were dosed with the USP formulation (90% versus 42% tumor growth inhibition). This reduction in activity of nanoparticle formulation appeared to result from a slower than anticipated dissolution in vivo. This study illustrates a need for careful consideration of both dose and systemic solubility prior utilizing nanosuspension as a mode of intravenous delivery. PMID:24685243

  5. Anticancer effects on TACC3 by treatment of paclitaxel in HPV-18 positive cervical carcinoma cells.

    PubMed

    Yim, Eun-Kyoung; Tong, Seo-Yun; Ho, Eun-Mi; Bae, Jeong-Hoon; Um, Soo-Jong; Park, Jong-Sup

    2009-02-01

    Previously, we used proteome analysis to identify transforming acidic coiled coil (TACC) 3 as a protein that is down-regulated upon paclitaxel treatment in cervical cancer cells. TACC3 mRNA and protein levels decreased after paclitaxel treatment in a time- and dose-dependent manner, and the transactivation of TACC3 promoter was dramatically diminished by paclitaxel. Importantly, paclitaxel treatment and knockdown of TACC3 by siRNA led to a synergistic enhancement of significant G2/M phase arrest and apoptosis in HeLa cells. In contrast to TACC3-deficient cells, paclitaxel treatment of mTACC3-overexpressing cells failed to induce G2/M phase arrest, cell growth inhibition, and apoptotic cell death. We studied the associated gene in mTACC overexpressed cells using microarray. From these results, numerous genes have been identified as being associated with tumor progression (Ppia, TMSB10, Annexin A2, rab31, prostaglandin E2-EP2, UHRF1), chemoresistance (Akt, Plk-1, MAP kinase) and metastasis (MMP9, PECAM-1) in mTACC3 overexpressed HeLa cells. Thus, TACC3 is thought to be the critical molecule in mediating the anticancer mechanisms of paclitaxel in p53 inactivated cells by inducing G2/M arrest and apoptosis. And our data suggested that the overexpression of TACC3 may be associated with the mechanisms of chemoresistance, tumor progression, cell proliferation and metastasis. PMID:19148534

  6. Effect of lipoic acid combined with paclitaxel on breast cancer cells.

    PubMed

    Li, B J; Hao, X Y; Ren, G H; Gong, Y

    2015-01-01

    Breast cancer is the most common gynecologic tumor globally that threatens women's health. Lipoic acid is a type of antioxidant that can alleviate oxidative stress damage. Studies showed that lipoic acid could inhibit the proliferation of tumor cells in cervical cancer and colon cancer. This paper intends to explore the combined effect of lipoic acid and paclitaxel on breast cancer cells. Breast cancer MCF-7 cells were divided into four groups: control group, lipoic acid group, paclitaxel group, and a combination group. MTT was applied to detect the drugs' influence on breast cancer cell proliferation. A colony formation test was used to determine the effects on breast cancer cell clone formation rate. Western blot was performed to detect the effects on nuclear factor (NF)-κB. Lipoic acid alone can inhibit tumor cell proliferation and clone formation with time dependence. Compared with the control, paclitaxel alone can significantly suppress tumor cell proliferation and clone formation (P < 0.05). Lipoic acid and paclitaxel in combination obviously strengthened their individual inhibitory effects on tumor cells (P < 0.05). Compared with the paclitaxel alone group, the combination group exhibited more remarkable inhibitory effect (P < 0.05). Lipoic acid alone or combined with paclitaxel can inhibit NF-κB expression and inhibit breast cancer cell proliferation. PMID:26782439

  7. Vaginal delivery of paclitaxel via nanoparticles with non-mucoadhesive surfaces suppresses cervical tumor growth

    PubMed Central

    Yang, Ming; Yu, Tao; Wang, Ying-Ying; Lai, Samuel K.; Zeng, Qi; Miao, Bolong; Tang, Benjamin C.; Simons, Brian W.; Ensign, Laura; Liu, Guanshu; Chan, Kannie W. Y.; Juang, Chih-Yin; Mert, Olcay; Wood, Joseph; Fu, Jie; McMahon, Michael T.; Wu, T.-C.; Hung, Chien-Fu; Hanes, Justin

    2014-01-01

    Local delivery of chemotherapeutics in the cervicovaginal tract using nanoparticles may reduce adverse side effects associated with systemic chemotherapy, while improving outcomes for early stage cervical cancer. We hypothesize drug-loaded nanoparticles must rapidly penetrate cervicovaginal mucus (CVM) lining the female reproductive tract to effectively deliver their payload to underlying diseased tissues in a uniform and sustained manner. We develop paclitaxel-loaded nanoparticles, composed entirely of polymers used in FDA-approved products, which rapidly penetrate human CVM and provide sustained drug release with minimal burst effect. We further employ a mouse model with aggressive cervical tumors established in the cervicovaginal tract to compare paclitaxel-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (conventional particles , or CP) and similar particles coated with Pluronic F127 (mucus-penetrating particles , or MPP). CP are mucoadhesive and, thus, aggregated in mucus, while MPP achieve more uniform distribution and close proximity to cervical tumors. Paclitaxel-MPP suppress tumor growth more effectively and prolong median survival of mice compared to free paclitaxel or paclitaxel-CP. Histopathological studies demonstrate minimal toxicity to the cervicovaginal epithelia, suggesting paclitaxel-MPP may be safe for intravaginal use. These results demonstrate for the first time the in vivo advantages of polymer-based MPP for treatment of tumors localized to a mucosal surface. PMID:24339398

  8. Human Mesenchymal Stem Cells Are Resistant to Paclitaxel by Adopting a Non-Proliferative Fibroblastic State

    PubMed Central

    Bosco, Dale B.; Kenworthy, Rachael; Zorio, Diego A. R.; Sang, Qing-Xiang Amy

    2015-01-01

    Human mesenchymal stem cell (hMSC) resistance to the apoptotic effects of chemotherapeutic drugs has been of major interest, as these cells can confer this resistance to tumor microenvironments. However, the effects of internalized chemotherapeutics upon hMSCs remain largely unexplored. In this study, cellular viability and proliferation assays, combined with different biochemical approaches, were used to investigate the effects of Paclitaxel exposure upon hMSCs. Our results indicate that hMSCs are highly resistant to the cytotoxic effects of Paclitaxel treatment, even though there was no detectable expression of the efflux pump P-glycoprotein, the usual means by which a cell resists Paclitaxel treatment. Moreover, Paclitaxel treatment induces hMSCs to adopt a non-proliferative fibroblastic state, as evidenced by changes to morphology, cellular markers, and a reduction in differentiation potential that is not directly coupled to the cytoskeletal effects of Paclitaxel. Taken together, our results show that Paclitaxel treatment does not induce apoptosis in hMSCs, but does induce quiescence and phenotypic changes. PMID:26029917

  9. A mucoadhesive in situ gel delivery system for paclitaxel.

    PubMed

    Jauhari, Saurabh; Dash, Alekha K

    2006-01-01

    MUC1 gene encodes a transmembrane mucin glycoprotein that is overexpressed in human breast cancer and colon cancer. The objective of this study was to develop an in situ gel delivery system containing paclitaxel (PTX) and mucoadhesives for sustained and targeted delivery of anticancer drugs. The delivery system consisted of chitosan and glyceryl monooleate (GMO) in 0.33M citric acid containing PTX. The in vitro release of PTX from the gel was performed in presence and absence of Tween 80 at drug loads of 0.18%, 0.30%, and 0.54% (wt/wt), in Sorensen's phosphate buffer (pH 7.4) at 37 degrees C. Different mucin-producing cell lines (Calu-3>Caco-2) were selected for PTX transport studies. Transport of PTX from solution and gel delivery system was performed in side by side diffusion chambers from apical to basal (A-B) and basal to apical (B-A) directions. In vitro release studies revealed that within 4 hours, only 7.61% +/- 0.19%, 12.0% +/- 0.98%, 31.7% +/- 0.40% of PTX were released from 0.18%, 0.30%, and 0.54% drug-loaded gel formulation, respectively, in absence of Tween 80. However, in presence of surfactant (0.05% wt/vol) in the dissolution medium, percentages of PTX released were 28.1% +/- 4.35%, 44.2% +/- 6.35%, and 97.1% +/- 1.22%, respectively. Paclitaxel has shown a polarized transport in all the cell monolayers with B-A transport 2 to 4 times higher than in the A-B direction. The highest mucin-producing cell line (Calu-3) has shown the lowest percentage of PTX transport from gels as compared with Caco-2 cells. Transport of PTX from mucoadhesive gels was shown to be influenced by the mucin-producing capability of cell. PMID:16796370

  10. Paclitaxel-induced hyposensitivity to nociceptive chemical stimulation in mice can be prevented by treatment with minocycline.

    PubMed

    Masocha, Willias

    2014-01-01

    Development of peripheral neuropathy, which can present as painful neuropathy or loss of sensation, sometimes limit the use of paclitaxel in the treatment of solid tumors such as breast cancer. Previous studies reported development of thermal hyperalgesia in mice treated with paclitaxel. In this study an automated flinch detection system for the formalin test (20 μl of 5% formalin injected subcutaneously into the paw dorsum) was used to evaluate chemical nociception in BALB/c mice treated with paclitaxel 2 mg/kg alone or coadministered with minocycline 50 mg/kg, intraperitoneally for 5 consecutive days. Reaction latency to thermal stimuli (hot-plate) was also measured. Injection of formalin resulted in biphasic paw flinches; phase 1 (1-9 minutes) and phase 2 (10-40 minutes). Treatment with paclitaxel reduced cumulative flinches in both phases 1 and 2 by 28% and 43%, respectively at day 7. However, treatment with paclitaxel also induced thermal hyperalgesia. Co-administration of paclitaxel with minocycline prevented development of both paclitaxel-induced hyposensitivity to chemical nociception and thermal hyperalgesia. In conclusion, the results indicate paclitaxel induces chemical hyposensitivity and thermal hyperalgesia in mice. Minocycline protected against paclitaxel-induced chemical hyposensitivity and thermal hyperalgesia, thus, providing further support of the usefulness of the drug in prevention of chemotherapy-induced neuropathy. PMID:25335491

  11. Targeting HDAC with a novel inhibitor effectively reverses paclitaxel resistance in non-small cell lung cancer via multiple mechanisms

    PubMed Central

    Wang, L; Li, H; Ren, Y; Zou, S; Fang, W; Jiang, X; Jia, L; Li, M; Liu, X; Yuan, X; Chen, G; Yang, J; Wu, C

    2016-01-01

    Chemotherapy paclitaxel yields significant reductions in tumor burden in the majority of advanced non-small cell lung cancer (NSCLC) patients. However, acquired resistance limits its clinical use. Here we demonstrated that the histone deacetylase (HDAC) was activated in paclitaxel-resistant NSCLC cells, and its activation promoted proliferation and tumorigenesis of paclitaxel-resistant NSCLC cells in vitro and in vivo. By contrast, knockdown of HDAC1, a primary isoform of HDAC, sensitized resistant cells to paclitaxel in vitro. Furthermore, we observed that overexpression of HDAC1 was associated with the downregulation of p21, a known HDAC target, in advanced NSCLC patients with paclitaxel treatment, and predicted chemotherapy resistance and bad outcome. In addition, we also identified a novel HDACs inhibitor, SNOH-3, which inhibited HDAC expression and activity, induced cell apoptosis, and suppressed cell migration, invasion and angiogenesis. Notably, co-treatment with SNOH-3 and paclitaxel overcome paclitaxel resistance through inhibiting HDAC activity, leading to the induction of apoptosis and suppression of angiogenesis in vitro and in preclinical model. In summary, our data demonstrate a role of HDAC in paclitaxel-resistant NSCLC and provide a promising therapeutic strategy to overcome paclitaxel-acquired resistance. PMID:26794658

  12. [Two cases of non-curatively resected scirrhous gastric cancer that responded well to weekly paclitaxel therapy].

    PubMed

    Suto, Ryuichiro; Nakafuji, Yoshito; Mochizuki, Kyoko; Oka, Kazunori; Jinbo, Mitsutaka; Chiba, Fumihiro; Moriuchi, Hiroki; Ikeda, Yuji; Nawata, Sumihiko; Zempo, Nobuya; Kurata, Satoru; Nakayasu, Kiyoshi; Esato, Kensuke; Kamei, Toshiaki

    2003-12-01

    We report 2 cases in which the weekly administration of paclitaxel proved to be effective for patients with scirrhous gastric cancer who underwent a curability C operation. Weekly paclitaxel therapy was observed to effectively treat peritoneal and retroperitoneal dissemination. After this treatment the tumor markers decreased markedly. This weekly paclitaxel therapy was observed to cause no adverse effects, and thanks to the treatment the patients were able to consume normal meals. These patients could also be sufficiently treated as outpatients. Weekly paclitaxel therapy is thus considered to be effective for the treatment of advanced scirrhous gastric cancer with peritoneal and retroperitoneal dissemination. PMID:14712775

  13. Paclitaxel inhibits cell proliferation and collagen lattice contraction via TGF-β signaling pathway in human tenon's fibroblasts in vitro.

    PubMed

    Chen, Ninghong; Guo, Dadong; Guo, Yuanyuan; Sun, Yuanyuan; Bi, Hongsheng; Ma, Xiaohua

    2016-04-15

    As an anti-microtubule agent, paclitaxel has been widely applied clinically. However, the effects of paclitaxel on human tenon's fibroblast (HTF) proliferation and migration in vitro was still unclear. In the present study, we explored the influences of paclitaxel on HTF cell proliferation, cell viability, cell cycle phase distribution under various concentrations of paclitaxel (i.e., 0, 10(-8), 10(-7), 10(-6)mol/l) via real-time cell electronic system and flow cytometry, further determined the expression of TGF-β1 and connective tissue growth factor (CTGF) after treatment with different concentrations of paclitaxel. Moreover, extra cellular matrix production and collagen lattice contraction assay were also explored. The results indicate that paclitaxel could apparently inhibit the cell viability, induces the elevation of S and G2/M phases of HTFs, and downregulates the expression of both TGF-β1 and CTGF. Meanwhile, the levels of fibronectin extra domain A (EDA), collagen and collagen lattice contraction were apparently reduced after treatment with paclitaxel. Overall, paclitaxel could apparently inhibit the proliferation of HTFs and leads to cell cycle arrest at both S and G2/M phases, attenuates the generation of collagen and collagen lattice contraction, decreases the expressions of TGF-β1, CTGF and fibronectin EDA. The inhibitory mechanism of paclitaxel on HTFs is involved in TGF-β1 signaling pathway. PMID:26930229

  14. ?-Tocopheryl succinate potentiates the paclitaxel-induced apoptosis through enforced caspase 8 activation in human H460 lung cancer cells

    PubMed Central

    Choi, Moon Kyung; Kim, Min Jung; Kim, Joo Kyoung

    2009-01-01

    Paclitaxel is one of the chemotheraputic drugs widely used for the treatment of nonsmall cell lung cancer (NSCLC) patients. Here, we tested the ability of ?-tocopheryl succinate (TOS), another promising anticancer agent, to enhance the paclitaxel response in NSCLC cells. We found that sub-apoptotic doses of TOS greatly enhanced paclitaxel-induced growth suppression and apoptosis in the human H460 NSCLC cell lines. Our data revealed that this was accounted for primarily by an augmented cleavage of poly(ADP-ribose) polymerase (PARP) and enhanced activation of caspase-8. Pretreatment with z-VAD-FMK (a pan-caspase inhibitor) or z-IETD-FMK (a caspase-8 inhibitor) blocked TOS/paclitaxel cotreatment-induced PARP cleavage and apoptosis, suggesting that TOS potentiates the paclitaxel-induced apoptosis through enforced caspase 8 activation in H460 cells. Furthermore, the growth suppression effect of TOS/paclitaxel combination on human H460, A549 and H358 NSCLC cell lines were synergistic. Our observations indicate that combination of paclitaxel and TOS may offer a novel therapeutic strategy for improving paclitaxel drug efficacy in NSCLC patient therapy as well as for potentially lowering the toxic side effects of paclitaxel through reduced drug dosage. PMID:19561399

  15. Extracellular biosynthesis of gadolinium oxide (Gd2O3) nanoparticles, their biodistribution and bioconjugation with the chemically modified anticancer drug taxol

    PubMed Central

    Khan, Shadab Ali; Gambhir, Sanjay

    2014-01-01

    Summary As a part of our programme to develop nanobioconjugates for the treatment of cancer, we first synthesized extracellular, protein-capped, highly stable and well-dispersed gadolinium oxide (Gd2O3) nanoparticles by using thermophilic fungus Humicola sp. The biodistribution of the nanoparticles in rats was checked by radiolabelling with Tc-99m. Finally, these nanoparticles were bioconjugated with the chemically modified anticancer drug taxol with the aim of characterizing the role of this bioconjugate in the treatment of cancer. The biosynthesized Gd2O3 nanoparticles were characterized by UV–vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoemission spectroscopy (XPS). The Gd2O3–taxol bioconjugate was confirmed by UV–vis spectroscopy and fluorescence microscopy and was purified by using high performance liquid chromatography (HPLC). PMID:24778946

  16. Paclitaxel Drug-Eluting Stents in Peripheral Arterial Disease: A Health Technology Assessment

    PubMed Central

    2015-01-01

    Background Peripheral arterial disease is a condition in which atherosclerotic plaques partially or completely block blood flow to the legs. Although percutaneous transluminal angioplasty and metallic stenting have high immediate success rates in treating peripheral arterial disease, long-term patency and restenosis rates in long and complex lesions remain unsatisfactory. Objective The objective of this analysis was to evaluate the clinical effectiveness, safety, cost-effectiveness and budget impact of Zilver paclitaxel self-expanding drug-eluting stents for the treatment of de novo or restenotic lesions in above-the-knee peripheral arterial disease. Data Sources Literature searches were performed using Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid Embase, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), and EBM Reviews. For the economic review, a search filter was applied to limit search results to economics-related literature. Data sources for the budget impact analysis included expert opinion, published literature, and Ontario administrative data. Review Methods Systematic reviews, meta-analyses, randomized controlled trials, and observational studies were included in the clinical effectiveness review, and full economic evaluations were included in the economic literature review. Studies were included if they examined the effect of Zilver paclitaxel drug-eluting stents in de novo or restenotic lesions in above-the-knee arteries. For the budget impact analysis, 3 scenarios were constructed based on different assumptions. Results One randomized controlled trial reported a significantly higher patency rate with Zilver paclitaxel drug-eluting stents for lesions ≤ 14 cm than with angioplasty or bare metal stents. One observational study showed no difference in patency rates between Zilver paclitaxel drug-eluting stents and paclitaxel drug-coated balloons. Zilver paclitaxel drug-eluting stents were associated with a significantly higher event-free survival rate than angioplasty, but the event-free survival rate was similar for Zilver paclitaxel drug-eluting stents and paclitaxel drug-coated balloons. No economic evaluations compared Zilver paclitaxel drug-eluting stents with bare metal stents or angioplasty for peripheral arterial disease. A budget impact analysis showed that the cost savings associated with funding of Zilver paclitaxel drug-eluting stents would be $470,000 to $640,000 per year, assuming that the use of the Zilver paclitaxel drug-eluting stent was associated with a lower risk of subsequent revascularization. Conclusions Based on evidence of low to moderate quality, Zilver paclitaxel drug-eluting stents were associated with a higher patency rate than angioplasty or bare metal stents, and with fewer adverse events than angioplasty. The effectiveness and safety of Zilver paclitaxel drug-eluting stents and paclitaxel drug-coated balloons were similar. PMID:26719778

  17. Paclitaxel attenuates renal interstitial fibroblast activation and interstitial fibrosis by inhibiting STAT3 signaling.

    PubMed

    Zhang, Lei; Xu, Xuan; Yang, Ruhao; Chen, Jingwen; Wang, Shixuan; Yang, Junqin; Xiang, Xudong; He, Zhibiao; Zhao, Yu; Dong, Zheng; Zhang, Dongshan

    2015-01-01

    Recent studies have demonstrated that paclitaxel might inhibit renal fibrosis. However, the underlying molecular mechanism remains unclear. In this study, we hypothesized that low-dose paclitaxel may block the STAT3 (signal transducer and activator of transcription 3) signaling to attenuate fibrosis in a mouse model with unilateral ureteral obstruction. Both NRK-49F cells and mice with unilateral ureteral obstruction were treated with paclitaxel. The results showed that paclitaxel treatment resulted in a dose- and time-dependent decrease in tyrosine-phosphorylated STAT3, and inhibited the expression of fibronectin, alpha-smooth muscle actin (α-SMA), and collagen I in cultured NRK-49F cells. S3I-201, an STAT3 inhibitor, also suppressed the expression of fibronectin, α-SMA, and collagen I in cultured NRK-49F cells. Mechanistically, paclitaxel treatment blocked the STAT3 activity by disrupting the association of STAT3 with tubulin and inhibiting STAT3 nucleus translocation. Furthermore, paclitaxel also ameliorated renal fibrosis by down-regulating the expression of fibronectin, α-SMA, and collagen I, and suppressed the infiltration of macrophages and production of TNF-α, IL-1β, TGF-β, and ICAM-1 (intercellular adhesion molecule 1) by inhibition of STAT3 activity in obstructive nephropathy. These results suggest that paclitaxel may block the STAT3 activity by disrupting the association of STAT3 with tubulin and inhibiting STAT3 nucleus translocation, consequently leading to the suppression of renal interstitial fibroblast activation and the development of renal fibrosis, and inhibition of proinflammatory cytokine production. PMID:25931810

  18. Quantitative proteomic analysis of mitochondria from human ovarian cancer cells and their paclitaxel-resistant sublines

    PubMed Central

    Chen, Ming; Huang, Hong; He, Haojie; Ying, Wantao; Liu, Xin; Dai, Zhiqin; Yin, Jie; Mao, Ning; Qian, Xiaohong; Pan, Lingya

    2015-01-01

    Paclitaxel resistance is a major obstacle for the treatment of ovarian cancer. The chemoresistance mechanisms are partly related to the mitochondria. Identification of the relevant proteins in mitochondria will help in clarifying the possible mechanisms and in selecting effective chemotherapy for patients with paclitaxel resistance. In the present study, mitochondria from two paclitaxel-sensitive human ovarian cancer cell lines (SKOV3 and A2780) and their corresponding resistant cell lines (SKOV3-TR and A2780-TR) were isolated. Guanidine-modified acetyl-stable isotope labeling and liquid chromatography-hybrid linear ion trap Fourier-transform ion cyclotron resonance mass spectrometry (LC-FTICR MS) were performed to find the expressed differential proteins. Comparative proteomic analysis revealed eight differentially expressed proteins in the ovarian cancer cells and their paclitaxel-resistant sublines. Among them, mimitin and 14-3-3 ζ/δ were selected for further research. The effects of mimitin and 14-3-3 ζ/δ were explored using specific siRNA interference in ovarian cancer cell lines and immunohistochemistry in human tissue specimens. The downregulation of mimitin and 14-3-3 ζ/δ using specific siRNA in paclitaxel-resistant ovarian cancer cells led to an increase in the resistance index to paclitaxel. Multivariate analyses demonstrated that lower expression levels of the mimitin and 14-3-3 ζ/δ proteins were positively associated with shorter progression-free survival (PFS) and overall survival (OS) in patients with primary ovarian cancer (mimitin: PFS: P = 0.041, OS: P = 0.003; 14-3-3 ζ/δ: PFS: P = 0.031, OS: P = 0.011). Mimitin and 14-3-3 protein ζ/δ are potential markers of paclitaxel resistance and prognostic factors in ovarian cancer. PMID:26033570

  19. Altered beta-tubulin isotype expression in paclitaxel-resistant human prostate carcinoma cells.

    PubMed

    Ranganathan, S; Benetatos, C A; Colarusso, P J; Dexter, D W; Hudes, G R

    1998-02-01

    To investigate the role of beta-tubulin isotype composition in resistance to paclitaxel, an anti-microtubule agent, human prostate carcinoma (DU-145) cells were intermittently exposed to increasing concentrations of paclitaxel. Cells that were selected and maintained at 10 nM paclitaxel (Pac-10) were fivefold resistant to the drug. Pac-10 cells accumulated radiolabelled paclitaxel to the same extent as DU-145 cells and were negative for MDR-1. Analysis of Pac-10 and DU-145 cells by flow cytometry showed similar cell cycle patterns. Immunofluorescent staining revealed an overall increase of alpha- and beta-tubulin levels in Pac-10 cells compared with DU-145 cells. Examination of beta-tubulin isotype composition revealed a significant increase in betaIII isotype in the resistant cells, both by immunofluorescence and by western blot analysis. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of the isotypes confirmed the increase observed for the betaIII by exhibiting ninefold higher betaIII mRNA levels and also showed fivefold increase of the betaIVa transcript. In addition, analysis of paclitaxel-resistant cells that were selected at increasing levels of the drug (Pac 2, 4, 6, 8 and 10) exhibited a positive correlation between increasing betaIII levels and increasing resistance to paclitaxel. Increased expression of specific beta-tubulin isotypes and subsequent incorporation into microtubules may alter cellular microtubule dynamics, providing a defence against the anti-microtubule effects of paclitaxel and other tubulin-binding drugs. PMID:9484812

  20. Altered beta-tubulin isotype expression in paclitaxel-resistant human prostate carcinoma cells.

    PubMed Central

    Ranganathan, S.; Benetatos, C. A.; Colarusso, P. J.; Dexter, D. W.; Hudes, G. R.

    1998-01-01

    To investigate the role of beta-tubulin isotype composition in resistance to paclitaxel, an anti-microtubule agent, human prostate carcinoma (DU-145) cells were intermittently exposed to increasing concentrations of paclitaxel. Cells that were selected and maintained at 10 nM paclitaxel (Pac-10) were fivefold resistant to the drug. Pac-10 cells accumulated radiolabelled paclitaxel to the same extent as DU-145 cells and were negative for MDR-1. Analysis of Pac-10 and DU-145 cells by flow cytometry showed similar cell cycle patterns. Immunofluorescent staining revealed an overall increase of alpha- and beta-tubulin levels in Pac-10 cells compared with DU-145 cells. Examination of beta-tubulin isotype composition revealed a significant increase in betaIII isotype in the resistant cells, both by immunofluorescence and by western blot analysis. Reverse transcription-polymerase chain reaction (RT-PCR) analysis of the isotypes confirmed the increase observed for the betaIII by exhibiting ninefold higher betaIII mRNA levels and also showed fivefold increase of the betaIVa transcript. In addition, analysis of paclitaxel-resistant cells that were selected at increasing levels of the drug (Pac 2, 4, 6, 8 and 10) exhibited a positive correlation between increasing betaIII levels and increasing resistance to paclitaxel. Increased expression of specific beta-tubulin isotypes and subsequent incorporation into microtubules may alter cellular microtubule dynamics, providing a defence against the anti-microtubule effects of paclitaxel and other tubulin-binding drugs. Images Figure 1 Figure 2 Figure 4 PMID:9484812

  1. HFT-T, a targeting nanoparticle, enhances specific delivery of paclitaxel to folate receptor-positive tumors.

    PubMed

    Wang, Xu; Li, Jun; Wang, Yiqing; Cho, Kwang Jae; Kim, Gloria; Gjyrezi, Ada; Koenig, Lydia; Giannakakou, Paraskevi; Shin, Hyung Ju C; Tighiouart, Mourad; Nie, Shuming; Chen, Zhuo Georgia; Shin, Dong M

    2009-10-27

    Nonspecific distribution of chemotherapeutic drugs (such as paclitaxel) is a major factor contributing to side effects and poor clinical outcomes in the treatment of human head and neck cancer. To develop novel drug delivery systems with enhanced efficacy and minimized adverse effects, we synthesized a ternary conjugate heparin-folic acid-paclitaxel (HFT), loaded with additional paclitaxel (T). The resulting nanoparticle, HFT-T, is expected to retain the antitumor activity of paclitaxel and specifically target folate receptor (FR)-expressing tumors, thereby increasing the bioavailability and efficacy of paclitaxel. In vitro experiments found that HFT-T selectively recognizes FR-positive human head and neck cancer cell line KB-3-1, displaying higher cytotoxicity compared to the free form of paclitaxel. In a subcutaneous KB-3-1 xenograft model, HFT-T administration enhanced the specific delivery of paclitaxel into tumor tissues and remarkably improved antitumor efficacy of paclitaxel. The average tumor volume in the HFT-T treatment group was 92.9 +/- 78.2 mm(3) vs 1670.3 +/- 286.1 mm(3) in the mice treated with free paclitaxel. Furthermore, paclitaxel tumors showed a resurgence of growth after several weeks of treatment, but this was not observed with HFT-T. This indicates that HFT-T could be more effective in preventing tumors from developing drug resistance. No significant acute in vivo toxicity was observed. These results indicate that specific delivery of paclitaxel with a ternary structured nanoparticle (HFT-T) targeting FR-positive tumor is a promising strategy to enhance chemotherapy efficacy and minimize adverse effects. PMID:19761191

  2. Paclitaxel sensitivity of breast cancer cells requires efficient mitotic arrest and disruption of Bcl-xL/Bak interaction.

    PubMed

    Flores, M Luz; Castilla, Carolina; Ávila, Rainiero; Ruiz-Borrego, Manuel; Sáez, Carmen; Japón, Miguel A

    2012-06-01

    Taxanes are being used for the treatment of breast cancer. However, cancer cells frequently develop resistance to these drugs with the subsequent recurrence of the tumor. MDA-MB-231 and T-47D breast cancer cell lines were used to assess the effect of paclitaxel treatment on apoptosis and cell cycle, the possible mechanisms of paclitaxel resistance as well as the enhancement of paclitaxel-induced apoptosis based on its combination with phenylethyl isothiocyanate (PEITC). T-47D cells undergo apoptosis in response to paclitaxel treatment. The induction of apoptosis was associated with a robust mitotic arrest and the disruption of Bcl-xL/Bak interaction. By contrary, MDA-MB-231 cells were insensitive to paclitaxel-induced apoptosis and this was associated with a high percentage of cells that slip out of paclitaxel-imposed mitotic arrest and also with the maintenance of Bcl-xL/Bak interaction. The sequential treatment of MDA-MB-231 cells with PEITC followed by paclitaxel inhibited the slippage induced by paclitaxel and increased the apoptosis induction achieved with any of the drugs alone. In breast cancer tissues, high Bcl-xL expression was correlated with a shorter time of disease-free survival in patients treated with a chemotherapeutic regimen that contains paclitaxel, in a statistically significant way. Thus, resistance to paclitaxel in MDA-MB-231 cells is related to the inability to disrupt the Bcl-xL/Bak interaction and increased slippage. In this context, the combination of a drug that induces a strong mitotic arrest, such as paclitaxel, with another that inhibits slippage, such as PEITC, translates into increased apoptotic induction. PMID:22076480

  3. Rapamycin potentiates the effects of paclitaxel in endometrial cancer cells through inhibition of cell proliferation and induction of apoptosis1

    PubMed Central

    Shafer, Aaron; Zhou, Chunxiao; Gehrig, Paola A.; Boggess, John F.; Bae-Jump, Victoria L.

    2009-01-01

    mTOR inhibitors modulate signaling pathways involved in cell cycle progression, and recent phase II trials demonstrate activity in endometrial cancer patients. Our objective was to examine the effects of combination therapy with rapamycin and paclitaxel in endometrial cancer cell lines. Paclitaxel inhibited proliferation in a dose-dependent manner in both cell lines with IC50 values of 0.1–0.5 nM and 1–5 nM for Ishikawa and ECC-1 cells, respectively. To assess synergy of paclitaxel and rapamycin, the combination index (CI) was calculated by the method of Chou and Talalay. Simultaneous exposure of cells to various doses of paclitaxel in combination with rapamycin (1 nM) resulted in a significant synergistic anti-proliferative effect (CI <1, range 0.131–0.920). Rapamycin alone did not induce apoptosis, but combined treatment with paclitaxel increased apoptosis over that of paclitaxel alone. Treatment with rapamycin and paclitaxel resulted in decreased phosphorylation of S6 and 4E-BP1, two critical downstream targets of the mTOR pathway. Rapamycin decreased hTERT mRNA expression by real-time RT-PCR while paclitaxel alone had no effect on telomerase activity. Paclitaxel increased polymerization and acetylation of tubulin, and rapamycin appeared to enhance this effect. Thus, in conclusion, we demonstrate that rapamycin potentiates the effects of paclitaxel in endometrial cancer cells through inhibition of cell proliferation, induction of apoptosis and potentially increased polymerization and acetylation of tubulin. This suggests that the combination of rapamycin and paclitaxel may be a promising effective targeted therapy for endometrial cancer. PMID:19688827

  4. The small molecule tyrosine kinase inhibitor NVP-BHG712 antagonizes ABCC10-mediated paclitaxel resistance: a preclinical and pharmacokinetic study.

    PubMed

    Kathawala, Rishil J; Wei, Liuya; Anreddy, Nagaraju; Chen, Kang; Patel, Atish; Alqahtani, Saeed; Zhang, Yun-Kai; Wang, Yi-Jun; Sodani, Kamlesh; Kaddoumi, Amal; Ashby, Charles R; Chen, Zhe-Sheng

    2015-01-01

    Paclitaxel exhibits clinical activity against a wide variety of solid tumors. However, resistance to paclitaxel significantly attenuates the response to chemotherapy. The ABC transporter subfamily C member 10 (ABCC10), also known as multi-drug resistance protein 7 (MRP7) efflux transporter, is a major mediator of paclitaxel resistance. Here, we determine the effect of NVP-BHG712, a specific EphB4 receptor inhibitor, on 1) paclitaxel resistance in HEK293 cells transfected with ABCC10, 2) the growth of tumors in athymic nude mice that received NVP-BHG712 and paclitaxel systemically and 3) the pharmacokinetics of paclitaxel in presence or absence of NVP-BHG712. NVP-BHG712 (0.5 μM), in HEK293/ABCC10 cells, significantly enhanced the intracellular accumulation of paclitaxel by inhibiting the efflux activity of ABCC10 without altering the expression level of the ABCC10 protein. Furthermore, NVP-BHG712 (25 mg/kg, p.o., q3d x 6), in combination with paclitaxel (15 mg/kg, i.p., q3d x 6), significantly inhibited the growth of ABCC10-expressing tumors in athymic nude mice. NVP-BHG712 administration significantly increased the levels of paclitaxel in the tumors but not in plasma compared to paclitaxel alone. The combination of NVP-BHG712 and paclitaxel could serve as a novel and useful therapeutic strategy to attenuate paclitaxel resistance mediated by the expression of the ABCC10 transporter. PMID:25402202

  5. Pharmacokinetics and pharmacodynamics of combination chemotherapy with paclitaxel and epirubicin in breast cancer patients

    PubMed Central

    Danesi, Romano; Innocenti, Federico; Fogli, Stefano; Gennari, Alessandra; Baldini, Editta; Di Paolo, Antonello; Salvadori, Barbara; Bocci, Guido; Conte, Pier Franco; Del Tacca, Mario

    2002-01-01

    Aims To investigate the pharmacokinetics and pharmacodynamics of epirubicin and paclitaxel in combination, as well as the effects of paclitaxel and its vehicle Cremophor EL on epirubicin metabolism. Methods Twenty-seven female patients with metastatic breast cancer received epirubicin 90 mg m−2 i.v. followed 15 min or 30 h later by a 3 h i.v. infusion of paclitaxel 175, 200 and 225 mg m−2. Plasma concentrations of paclitaxel, epirubicin and epirubicinol were measured and the relationship between neutropenia and drug pharmacokinetics was evaluated using a sigmoid maximum effect (Emax) model. Finally, the influence of paclitaxel and Cremophor EL on epirubicin metabolism by whole blood was examined. Results An increase in epirubicinol plasma concentrations occurred after the start of the paclitaxel infusion, resulting in a significant increase in the area under the plasma concentration-time curve (AUC) of epirubicinol (+0.5 µmol l−1 h [95% CI for the difference: 0.29, 0.71],+0.66 µmol l−1 h [95% CI for the difference: 0.47, 0.85] and +0.82 µmol l−1 h [95% CI for the difference: 0.53, 1.11] at paclitaxel doses of 175, 200 and 225 mg m−2, respectively), compared with epirubicin followed by paclitaxel 30 h later (0.61±0.1 µmol l−1 h). A significant increase in epirubicin AUC (+0.74 µmol l−1 h [95% CI for the difference: 0.14, 1.34] and +1.09 µmol l−1 h [95% CI for the difference: 0.44, 1.74]) and decrease in drug clearance (CLTB) (−25.35 l h−1 m−2[95% CI for the difference: −50.18, −0.52] and −35.9 l h−1 m−2[95% CI for the difference −63,4,−8,36]) occurred in combination with paclitaxel 200 and 225 mg m−2 with respect to the AUC (3.16±0.6 µmol l−1 h) and CLTB (74.4±28.4 l h−1 m−2) of epirubicin followed by paclitaxel 30 h later. An Emax relationship was observed between neutropaenia and the time over which paclitaxel plasma concentrations were equal to or greater than 0.1 µmol l−1 (tC0.1). The tC0.1 value predicted to yield a 50% decrease in neutrophil count was 7.7 h. Finally, Cremophor EL markedly inhibited the metabolism of epirubicin to epirubicinol in whole blood. Conclusions Paclitaxel/Cremophor EL affects the disposition of epirubicinol and epirubicin. Furthermore, the slope factor of the Emax relationship between neutropenia and tC0.1 of paclitaxel suggests that the drugs might also interact at the pharmacodynamic level. PMID:11994057

  6. Paclitaxel tumor priming promotes delivery and transfection of intravenous lipid-siRNA in pancreatic tumors.

    PubMed

    Wang, Jie; Lu, Ze; Wang, Junfeng; Cui, Minjian; Yeung, Bertrand Z; Cole, David J; Wientjes, M Guillaume; Au, Jessie L-S

    2015-10-28

    The major barrier for using small interfering RNA (siRNA) as cancer therapeutics is the inadequate delivery and transfection in solid tumors. We have previously shown that paclitaxel tumor priming, by inducing apoptosis, expands the tumor interstitial space, improves the penetration and dispersion of nanoparticles and siRNA-lipoplexes in 3-dimensional tumor histocultures, and promotes the delivery and transfection efficiency of siRNA-lipoplexes under the locoregional setting in vivo (i.e., intraperitoneal treatment of intraperitoneal tumors). The current study evaluated whether tumor priming is functional for systemically delivered siRNA via intravenous injection, which would subject siRNA to several additional delivery barriers and elimination processes. We used the same pegylated cationic (PCat)-siRNA lipoplexes as in the intraperitoneal study to treat mice bearing subcutaneous human pancreatic Hs766T xenograft tumors. The target gene was survivin, an inducible chemoresistance gene. The results show single agent paclitaxel delayed tumor growth but also significantly induced the survivin protein level in residual tumors, whereas addition of PCat-siSurvivin completely reversed the paclitaxel-induced survivin and enhanced the paclitaxel activity (p<0.05). In comparison, PCat-siSurvivin alone did not yield survivin knockdown or antitumor activity, indicating the in vivo effectiveness of intravenous siRNA-mediated gene silencing requires paclitaxel cotreatment. Additional in vitro studies showed that paclitaxel promoted the cytoplasmic release of siGLO, a 22 nucleotide double-stranded RNA that has no mRNA targets, from its PCat lipoplex and/or endosomes/lysosomes. Taken together, our earlier and current data show paclitaxel tumor priming, by promoting the interstitial transport and cytoplasmic release, is critical to promote the delivery and transfection of siRNA in vivo. In addition, because paclitaxel has broad spectrum activity and is used to treat multiple types of solid tumors including the hard-to-treat pancreatic cancer, the synergistic paclitaxel+siSurvivin combination represents a potentially useful chemo-gene therapy. PMID:26272765

  7. Androgen and taxol cause cell type-specific alterations of centrosome and DNA organization in androgen-responsive LNCaP and androgen-independent DU145 prostate cancer cells

    NASA Technical Reports Server (NTRS)

    Schatten, H.; Ripple, M.; Balczon, R.; Weindruch, R.; Chakrabarti, A.; Taylor, M.; Hueser, C. N.

    2000-01-01

    We investigated the effects of androgen and taxol on the androgen-responsive LNCaP and androgen-independent DU145 prostate cancer cell lines. Cells were treated for 48 and 72 h with 0.05-1 nM of the synthetic androgen R1881 and with 100 nM taxol. Treatment of LNCaP cells with 0.05 nM R1881 led to increased cell proliferation, whereas treatment with 1 nM R1881 resulted in inhibited cell division, DNA cycle arrest, and altered centrosome organization. After treatment with 1 nM R1881, chromatin became clustered, nuclear envelopes convoluted, and mitochondria accumulated around the nucleus. Immunofluorescence microscopy with antibodies to centrosomes showed altered centrosome structure. Although centrosomes were closely associated with the nucleus in untreated cells, they dispersed into the cytoplasm after treatment with 1 nM R1881. Microtubules were only faintly detected in 1 nM R1881-treated LNCaP cells. The effects of taxol included microtubule bundling and altered mitochondria morphology, but not DNA organization. As expected, the androgen-independent prostate cancer cell line DU145 was not affected by R1881. Treatment with taxol resulted in bundling of microtubules in both cell lines. Additional taxol effects were seen in DU145 cells with micronucleation of DNA, an indication of apoptosis. Simultaneous treatment with R1881 and taxol had no additional effects on LNCaP or DU145 cells. These results suggest that LNCaP and DU145 prostate cancer cells show differences not only in androgen responsiveness but in sensitivity to taxol as well. Copyright 2000 Wiley-Liss, Inc.

  8. Paclitaxel sensitivity in relation to ABCB1 expression, efflux and single nucleotide polymorphisms in ovarian cancer.

    PubMed

    Gao, Bo; Russell, Amanda; Beesley, Jonathan; Chen, Xiao Qing; Healey, Sue; Henderson, Michelle; Wong, Mark; Emmanuel, Catherine; Galletta, Laura; Johnatty, Sharon E; Bowtell, David; Haber, Michelle; Norris, Murray; Harnett, Paul; Chenevix-Trench, Georgia; Balleine, Rosemary L; deFazio, Anna

    2014-01-01

    ABCB1 (adenosine triphosphate-binding cassette transporter B1) mediates cellular elimination of many chemotherapeutic agents including paclitaxel, which is commonly used to treat ovarian cancer. A significant association between common single nucleotide polymorphisms (SNPs) in ABCB1 and progression-free survival has been reported in patients with ovarian cancer. Variable paclitaxel clearance due to genotype specific differences in ABCB1 activity in cancer cells and/or normal tissues may underlie the association. Using cell-based models, we evaluated the correlations between ABCB1 expression, polymorphisms, transporter activity and paclitaxel sensitivity in ovarian cancer (n = 10) and lymphoblastoid (n = 19) cell lines. Close associations between ABCB1 expression, transporter function and paclitaxel sensitivity were found in lymphoblastoid cell lines, although we could not demonstrate an association with common SNPs. In ovarian cancer cell lines, ABCB1 expression was low and the association between expression and function was lost. These results suggest that ABCB1 related survival difference in ovarian cancer patients is more likely to be due to differential whole body paclitaxel clearance mediated by normal cells rather than a direct effect on cancer cells. PMID:24810093

  9. Paclitaxel Induced MDS and AML: A Case Report and Literature Review

    PubMed Central

    Bhatnagar, Udit Bhaskar; Singh, Daulath; Glazyrin, Alexy; Moormeier, Jill

    2016-01-01

    Therapy related acute myelogenous leukemia (AML) and myelodysplastic syndromes (MDS) have been classically linked to alkylating agents and topoisomerase inhibitors. They constitute about 1% of all AMLs. There is less evidence on association of taxanes (paclitaxel and docetaxel) with these myeloid neoplasms. We present a case of paclitaxel therapy related acute myelogenous leukemia after treatment of endometrial cancer with a regimen containing paclitaxel and carboplatin. A 63-year-old female underwent surgery followed by a total of 6 cycles of chemotherapy with carboplatin and paclitaxel. Six months after last cycle of chemotherapy, she was diagnosed with myelodysplastic syndrome with refractory anemia and excess blasts. Six weeks later, she had worsening anemia and thrombocytopenia which prompted a bone marrow biopsy which revealed acute myelomonocytic leukemia. A thorough literature review revealed 12 other case reports where taxanes have been implicated in the development of therapy related myeloid neoplasm. Based on the timeline of events in our patient, paclitaxel is the likely culprit in the pathogenesis of this myeloid neoplasm. This rare but significantly grave adverse effect should be kept in consideration when deciding on treatment options for gynecological malignancies. PMID:27057370

  10. E2F Inhibition Synergizes with Paclitaxel in Lung Cancer Cell Lines

    PubMed Central

    Kurtyka, Courtney A.; Chen, Lu; Cress, W. Douglas

    2014-01-01

    The CDK/Rb/E2F pathway is commonly disrupted in lung cancer, and thus, it is predicted that blocking the E2F pathway would have therapeutic potential. To test this hypothesis, we have examined the activity of HLM006474 (a small molecule pan-E2F inhibitor) in lung cancer cell lines as a single agent and in combination with other compounds. HLM006474 reduces the viability of both SCLC and NSCLC lines with a biological IC50 that varies between 15 and 75 µM, but with no significant difference between the groups. Combination of HLM006474 with cisplatin and gemcitabine demonstrate little synergy; however, HLM006474 synergizes with paclitaxel. Surprisingly, we discovered that brief treatment of cells with HLM006474 led to an increase of E2F3 protein levels (due to de-repression of these promoter sites). Since paclitaxel sensitivity has been shown to correlate with E2F3 levels, we hypothesized that HLM006474 synergy with paclitaxel may be mediated by transient induction of E2F3. To test this, H1299 cells were depleted of E2F3a and E2F3b with siRNA and treated with paclitaxel. Assays of proliferation showed that both siRNAs significantly reduced paclitaxel sensitivity, as expected. Taken together, these results suggest that HLM006474 may have efficacy in lung cancer and may be useful in combination with taxanes. PMID:24831239

  11. IRAK1 is a therapeutic target that drives breast cancer metastasis and resistance to paclitaxel

    PubMed Central

    Wee, Zhen Ning; Yatim, Siti Maryam J. M.; Kohlbauer, Vera K; Feng, Min; Goh, Jian Yuan; Yi, Bao; Lee, Puay Leng; Zhang, Songjing; Wang, Pan Pan; Lim, Elgene; Tam, Wai Leong; Cai, Yu; Ditzel, Henrik J; Hoon, Dave S. B.; Tan, Ern Yu; Yu, Qiang

    2015-01-01

    Metastatic tumour recurrence due to failed treatments remains a major challenge of breast cancer clinical management. Here we report that interleukin-1 receptor-associated kinase 1 (IRAK1) is overexpressed in a subset of breast cancers, in particular triple-negative breast cancer (TNBC), where it acts to drive aggressive growth, metastasis and acquired resistance to paclitaxel treatment. We show that IRAK1 overexpression confers TNBC growth advantage through NF-κB-related cytokine secretion and metastatic TNBC cells exhibit gain of IRAK1 dependency, resulting in high susceptibility to genetic and pharmacologic inhibition of IRAK1. Importantly, paclitaxel treatment induces strong IRAK1 phosphorylation, an increase in inflammatory cytokine expression, enrichment of cancer stem cells and acquired resistance to paclitaxel treatment. Pharmacologic inhibition of IRAK1 is able to reverse paclitaxel resistance by triggering massive apoptosis at least in part through inhibiting p38-MCL1 pro-survival pathway. Our study thus demonstrates IRAK1 as a promising therapeutic target for TNBC metastasis and paclitaxel resistance. PMID:26503059

  12. A clinical and pharmacokinetic study of the combination of carboplatin and paclitaxel for epithelial ovarian cancer.

    PubMed Central

    Siddiqui, N.; Boddy, A. V.; Thomas, H. D.; Bailey, N. P.; Robson, L.; Lind, M. J.; Calvert, A. H.

    1997-01-01

    The aim of this phase I study was to determine the maximum tolerated dose of a 3-h infusion of paclitaxel, combined with carboplatin at a fixed AUC of 7 mg ml-1 min every 4 weeks for up to six cycles and to evaluate any possible pharmacokinetic interaction. Twelve chemonaive patients with ovarian cancer were treated with paclitaxel followed by a 30-min infusion of carboplatin. Paclitaxel dose was escalated from 150 mg m-2 to 225 mg m-2 in cohorts of three patients. Carboplatin dose was based on renal function. Pharmacokinetic studies were performed in nine patients (at least two at each dose level). A total of 66 courses were evaluable for assessment. Grade 3 or 4 neutropenia was seen in 70% of the courses, however hospitalization was not required. Grade 3 or 4 thrombocytopenia occurred in 24% of the courses. Alopecia, myalgia and peripheral neuropathy were common but rarely severe. The pharmacokinetics of paclitaxel was non-linear and did not appear to be influenced by co-administration of carboplatin. The AUC of carboplatin was 7.0 +/- 1.4 mg ml-1 min, indicating that there was no pharmacokinetic interaction. The combination of carboplatin and paclitaxel may be administered as first-line treatment for advanced ovarian cancer. Although myelosuppression is the dose-limiting toxicity of the component drugs, the severity of thrombocytopenia was less than anticipated. The results of this study, with only a small number of patients, need to be confirmed in future investigations. PMID:9010040

  13. Elevated MARCKS phosphorylation contributes to unresponsiveness of breast cancer to paclitaxel treatment

    PubMed Central

    Chen, Ching-Hsien; Cheng, Chun-Ting; Yuan, Yuan; Zhai, Jing; Arif, Muhammad; Fong, Lon Wolf R.; Wu, Reen; Ann, David K.

    2015-01-01

    Accumulating evidence has suggested that myristoylated alanine-rich C-kinase substrate (MARCKS) is critical for regulating multiple pathophysiological processes. However, the molecular mechanism underlying increased phosphorylation of MARCKS at Ser159/163 (phospho-MARCKS) and its functional consequence in neoplastic disease remain to be established. Herein, we investigated how phospho-MARCKS is regulated in breast carcinoma, and its role in the context of chemotherapy. In a screen of patients with breast tumors, we find that the abundance of phospho-MARCKS, not MARCKS protein per se, increased in breast cancers and positively correlated with tumor grade and metastatic status. Among chemotherapeutic agents, mitotic inhibitors, including paclitaxel, vincristine or eribulin, notably promoted phospho-MARCKS accumulation in multiple breast cancer cells. We further show that phospho-MARCKS acted upstream of Src activation upon paclitaxel exposure. Reduction of phospho-MARCKS by knockdown of MARCKS or pharmacological agents increased paclitaxel sensitivity. Particularly, a known phospho-MARCKS inhibitor, MANS peptide, was demonstrated to increase paclitaxel efficacy and attenuate angiogenesis/metastasis of xenografted breast cancer cells by decreasing abundance of phospho-MARCKS and messages of inflammatory mediators. Our data suggest that unresponsiveness of breast cancer to paclitaxel treatment is, at least in part, mediated by phospho-MARCKS and also provide an alternative therapeutic strategy against breast cancer by improving taxanes sensitivity. PMID:26015406

  14. Paclitaxel reduces formation of hypertrophic scars in the rabbit ear model

    PubMed Central

    Huang, Li-ping; Wang, Guo-qi; Jia, Zi-shan; Chen, Jing-wen; Wang, Gang; Wang, Xing-lin

    2015-01-01

    Background and objective The onset and progression of pathological scarring involves multiple cytokines and complex mechanisms. However, hyperplasia of fibroblasts and neovascularization plays important roles, which can be inhibited by paclitaxel. The aim of this study was to investigate the efficacy of paclitaxel in the treatment of hypertrophic scars on rabbit ears. Methods Rabbit ear models of hypertrophic scars were established to observe the therapeutic effects of paclitaxel at different concentrations (12 mg/L, 24 mg/L, 48 mg/L, 96 mg/L, 18 mg/L, 54 mg/L, 162 mg/L, 486 mg/L, 30 mg/L, 150 mg/L, 750 mg/L, 3,750 mg/L). The outcome measures included hypertrophic index (HI), density of fibroblasts, density of collagenous fibers, and microvessel density. Results In comparison with the control group, the concentrations of 96 mg/L, 150 mg/L, and 162 mg/L significantly reduce the formation of hypertrophic scars in the rabbit ear models. However, local necrosis was found in the rabbit ear models treated with paclitaxel solution >400 mg/L. Conclusion Paclitaxel has strong inhibitory effects on the hyperplasia of fibroblasts, deposition of collagen, and microangiogenesis in hypertrophic scars on rabbit ears within the concentration range from 48 mg/L to 162 mg/L, without causing local necrosis. PMID:26251604

  15. Efficacy of poly(sebacic acid-co-ricinoleic acid) biodegradable delivery system for intratumoral delivery of paclitaxel.

    PubMed

    Shikanov, Ariella; Vaisman, Boris; Shikanov, Sergey; Domb, Abraham J

    2010-03-15

    The effectiveness of an injectable polymeric formulation, based on poly(sebacic acid-co-ricinoleic acid) and paclitaxel against a heterotopic tumor model was studied. An injectable pasty polymer that releases an incorporated drug over a period of weeks was used. The degradation rate of formulations with paclitaxel was examined in vitro and in vivo. The effectiveness of the polymeric carrier of paclitaxel was investigated using a melanoma heterotopic model in C57BL/6 mice. Tumor bearing animals were injected intratumorally with 0.1 ml of formulations containing 5%, 10%, 15%, and 20% paclitaxel. Formulations with 5% and 10% paclitaxel content degraded faster in vivo then in vitro. Changes in tumor progression, survival time, and body weight were observed over a period of 77 days. The highest tumor size was reported for the control groups that did not receive paclitaxel in their treatment regiment: 3.6 g on day 20, while in all groups treated with polymer loaded with paclitaxel the tumor size was much smaller than that in the blank polymer or non treatment groups and ranged from 1.3 g to 0.3 g. Intratumoral injection of paclitaxel loaded in the polymer was found to be an effective treatment for localized tumors. PMID:19343769

  16. Pharmacokinetic and efficacy study of cisplatin and paclitaxel formulated in a new injectable poly(sebacic-co-ricinoleic acid) polymer.

    PubMed

    Levy-Nissenbaum, Etgar; Khan, Wahid; Pawar, Rajendra P; Tabakman, Rinat; Naftali, Esmira; Winkler, Ilan; Kaufman, Olga; Klapper, Leah; Domb, Abraham J

    2012-09-01

    Injectable biodegradable polymer poly(sebacic-co-ricinoleic acid), P(SA-RA) is currently under development for intratumoral (IT) delivery of drugs for treating solid tumors. This study presents formulation development, pharmacokinetic and efficacy studies of two anticancer drugs (cisplatin and paclitaxel) formulated with P(SA-RA) polymer. In pharmacokinetic study, systemic exposure and pharmacokinetic parameters of cisplatin/paclitaxel following single intravenous (IV) or subcutaneous (SC) doses of cisplatin/paclitaxel was compared with intramuscular (IM) or SC doses of cisplatin/paclitaxel formulated with P(SA-RA) polymer in male CD rat. Simultaneously, the tumor reduction effect and toxicity for these formulations were evaluated in human FaDu head and neck tumor xenograft subcutaneous nude mouse model. Pharmacokinetic data reflect the lower maximal concentrations and sustained release of polymer-cisplatin/paclitaxel formulations compared to standard cisplatin/paclitaxel administration. Regarding efficacy study, a single IT or near the tumor injection (NT) of polymer-paclitaxel or polymer-cisplatin formulation significantly reduced the tumor size, compared to the standard paclitaxel or cisplatin treatments. No death or toxicity and no effect on body weight as well as macroscopic and/or microscopic changes in or near the injected area were observed, proving biocompatibility and acceptability of polymer-formulations. In conclusion, the developed formulation demonstrated controlled release and significant efficacy in delivering these agents and exhibit potential for further clinical development. PMID:22732267

  17. Contribution of taxane biosynthetic pathway gene expression to observed variability in paclitaxel accumulation in Taxus suspension cultures

    PubMed Central

    Patil, Rohan A.; Kolewe, Martin E.; Normanly, Jennifer; Walker, Elsbeth L.; Roberts, Susan C.

    2012-01-01

    Variability in product accumulation is one of the major obstacles limiting the widespread commercialization of plant cell culture technology to supply natural product pharmaceuticals. Despite extensive process engineering efforts, which have led to increased yields, plant cells exhibit variability in productivity that is poorly understood. Elicitation of Taxus cultures with methyl jasmonate (MeJA) induces paclitaxel accumulation, but to varying extents in different cultures. In this work, cultures with different aggregation profiles were established to create predictable differences in paclitaxel accumulation upon MeJA elicitation. Expression of known paclitaxel biosynthetic genes in MeJA-elicited cultures exhibiting both substantial (15-fold) and moderate (2-fold) differences in paclitaxel accumulation was analyzed using qRT-PCR. Each population exhibited the characteristic large increase in paclitaxel pathway gene expression following MeJA elicitation; however, differences in expression between populations were minor, and only observed for the cultures with the 15-fold variation in paclitaxel content. These data suggest that although upregulation of biosynthetic pathway gene expression contributes to observed increases in paclitaxel synthesis upon elicitation with MeJA, there are additional factors that need to be uncovered before paclitaxel productivity can be fully optimized. PMID:22095859

  18. Paclitaxel inhibits selenoprotein S expression and attenuates endoplasmic reticulum stress

    PubMed Central

    QIN, HONG-SHUANG; YU, PEI-PEI; SUN, YING; WANG, DAN-FENG; DENG, XIAO-FEN; BAO, YONG-LI; SONG, JUN; SUN, LU-GUO; SONG, ZHEN-BO; LI, YU-XIN

    2016-01-01

    The primary effect of the endoplasmic reticulum (ER) stress response or unfolded protein response (UPR) is to reduce the load of unfolded protein and promote survival. However, prolonged and severe ER stress leads to tissue injury and serious diseases. Thus, it is important to identify drugs that can attenuate ER stress for the treatment of diseases. Natural products continue to provide lead compounds for drug discovery and front-line pharmacotherapy for people worldwide. Previous studies have indicated that selenoprotein S (SelS) is a sensitive and ideal maker of ER stress. In the present study, a firefly luciferase reporter driven by the SelS gene promoter was used to screen for natural compounds capable of attenuating ER stress. From this, paclitaxel (PTX) was identified to efficiently inhibit the promoter activity of the SelS gene, and further results revealed that PTX significantly inhibited the tunicamycin-induced upregulation of SelS at the mRNA and protein levels in HepG2 and HEK293T cells. In addition, PTX was able to efficiently inhibit the expression of the ER stress marker, glucose-regulated protein 78, in ER stress, indicating that PTX may reverse ER stress. Taken together, these results suggest that PTX is able to inhibit SelS expression during ER stress and attenuate ER stress. PMID:27109260

  19. Paclitaxel inhibits selenoprotein S expression and attenuates endoplasmic reticulum stress.

    PubMed

    Qin, Hong-Shuang; Yu, Pei-Pei; Sun, Ying; Wang, Dan-Feng; Deng, Xiao-Fen; Bao, Yong-Li; Song, Jun; Sun, Lu-Guo; Song, Zhen-Bo; Li, Yu-Xin

    2016-06-01

    The primary effect of the endoplasmic reticulum (ER) stress response or unfolded protein response (UPR) is to reduce the load of unfolded protein and promote survival. However, prolonged and severe ER stress leads to tissue injury and serious diseases. Thus, it is important to identify drugs that can attenuate ER stress for the treatment of diseases. Natural products continue to provide lead compounds for drug discovery and front‑line pharmacotherapy for people worldwide. Previous studies have indicated that selenoprotein S (SelS) is a sensitive and ideal maker of ER stress. In the present study, a firefly luciferase reporter driven by the SelS gene promoter was used to screen for natural compounds capable of attenuating ER stress. From this, paclitaxel (PTX) was identified to efficiently inhibit the promoter activity of the SelS gene, and further results revealed that PTX significantly inhibited the tunicamycin‑induced upregulation of SelS at the mRNA and protein levels in HepG2 and HEK293T cells. In addition, PTX was able to efficiently inhibit the expression of the ER stress marker, glucose‑regulated protein 78, in ER stress, indicating that PTX may reverse ER stress. Taken together, these results suggest that PTX is able to inhibit SelS expression during ER stress and attenuate ER stress. PMID:27109260

  20. Programmed Hydrolysis in Designing Paclitaxel Prodrug for Nanocarrier Assembly

    PubMed Central

    Fu, Q.; Wang, Y.; Ma, Y.; Zhang, D.; Fallon, J. K.; Yang, X.; Liu, D.; He, Z.; Liu, F.

    2015-01-01

    Nanocarriers delivering prodrugs are a way of improving in vivo effectiveness and efficiency. For therapeutic efficacy, the prodrug must hydrolyze to its parent drug after administration. Based on the fact that the hydrolysis is impeded by steric hindrance and improved by sufficient polarity, in this study, we proposed the PTX-S-S-VE, the conjugation of paclitaxel (PTX) to vitamin E (VE) through a disulfide bridge. This conjugate possessed the following advantages: first, it can be encapsulated in the VE/VE2-PEG2000/water nanoemulsions because of favorable hydrophobic interactions; second, the nanoemulsions had a long blood circulation time; finally, the concentrated glutathione in the tumor microenvironment could cleave the disulfide bond to weaken the steric hindrance and increase the polarity, promoting the hydrolysis to PTX and increasing the anticancer activity. It was demonstrated in vitro that the hydrolysis of PTX-S-S-VE was enhanced and the cytotoxicity was increased. In addition, PTX-S-S-VE had greater anticancer activity against the KB-3-1 cell line tumor xenograft and the tumor size was smaller after the 4th injection. The present result suggests a new way, use of reduction, to improve the in vivo anticancer activity of a prodrug for nanocarrier delivery by unshielding the ester bond and taking off the steric block. PMID:26166066

  1. Targeting of albumin-embedded paclitaxel nanoparticles to tumors

    PubMed Central

    Karmali, Priya Prakash; Kotamraju, Venkata Ramana; Kastantin, Mark; Black, Matthew; Missirlis, Dimitris; Tirrell, Matthew; Ruoslahti, Erkki

    2010-01-01

    We have used tumor-homing peptides to target abraxane, a clinically approved paclitaxel-albumin nanoparticle, to tumors in mice. The targeting was accomplished with two peptides, CREKA, and LyP-1 (CGQKRTRGC). Fluorescein (FAM)-labeled CREKA-abraxane, when injected intravenously into mice bearing MDA-MB-435 human cancer xenografts, accumulated in tumor blood vessels, forming aggregates that contained red blood cells and fibrin. FAM-LyP-1-abraxane co-localized with extravascular islands expressing its receptor, p32. Self-assembled mixed micelles carrying the homing peptide and the label on different subunits accumulated in the same areas of tumors as LyP-1-abraxane, showing that Lyp-1 can deliver intact nanoparticles into extravascular sites. Untargeted, FAM-abraxane was detected in the form of a faint meshwork in tumor interstitium. LyP-1-abraxane produced a statistically highly significant inhibition of tumor growth compared to untargeted abraxane. These results show that nanoparticles can be effectively targeted into extravascular tumor tissue and that targeting can enhance the activity of a therapeutic nanoparticle. PMID:18829396

  2. Delivery of paclitaxel using PEGylated graphene oxide as a nanocarrier.

    PubMed

    Xu, Zhiyuan; Zhu, Shaojia; Wang, Mingwei; Li, Yongjun; Shi, Ping; Huang, Xiaoyu

    2015-01-21

    Paclitaxel (PTX) is an extensively used potent chemotherapy drug; however, low water solubility, poor bioavailability, and emergence of drug resistance in patients limited its biological application. In this report, we proposed a new drug delivery system for cancer therapy based on graphene oxide (GO), a novel 2D nanomaterial obtained from the oxidation of natural graphite, to improve the utilization rate of PTX. PTX was first connected to biocompatible 6-armed poly(ethylene glycol), followed by covalent introduction into the surface of GO sheets via a facile amidation process under mild conditions, affording the drug delivery system, GO-PEG-PTX (size 50-200 nm). GO-PEG nanosized carrier could quickly enter into human lung cancer A549 and human breast cancer MCF-7 cells verified by inverted fluorescence microscope using fluorescein isothiocyanate as probe. This nanocarrier was nontoxic to A549 and MCF-7 cells without linking with PTX. Nevertheless, GO-PEG-PTX showed remarkably high cytotoxicity to A549 and MCF-7 cells in a broad range of concentration of PTX and time compared to free PTX. This kind of nanoscale drug delivery system based on PEGylated GO may find widespread application in biomedicine. PMID:25546399

  3. Constitutive Androstane Receptor Ligands Modulate the Anti-Tumor Efficacy of Paclitaxel in Non-Small Cell Lung Cancer Cells

    PubMed Central

    Fukumasu, Heidge; Rochetti, Arina L.; Pires, Pedro R. L.; Silva, Edson R.; Mesquita, Ligia G.; Strefezzi, Ricardo F.; De Carvalho, Daniel D.; Dagli, Maria L.

    2014-01-01

    Background Lung tumors are the leading cause of cancer deaths worldwide and paclitaxel has proven to be useful for patients with lung cancer, however, acquired resistance is a major problem. To overcome this problem, one promising option is the use of Constitutive Androstane Receptor (CAR) ligands in combination with chemotherapeutics against cancer cells. Therefore, we wish to elucidate the effects of CAR ligands on the antineoplastic efficacy of paclitaxel in lung cancer cells. Methodology/Principal Findings Our results from cell viability assays exposing CAR agonist or inverse-agonist to mouse and human lung cancer cells modulated the antineoplastic effect of paclitaxel. The CAR agonists increased the effect of Paclitaxel in 6 of 7 lung cancer cell lines, whereas the inverse-agonist had no effect on paclitaxel cytotoxicity. Interestingly, the mCAR agonist TCPOBOP enhanced the expression of two tumor suppressor genes, namely WT1 and MGMT, which were additively enhanced in cells treated with CAR agonist in combination with paclitaxel. Also, in silico analysis showed that both paclitaxel and CAR agonist TCPOBOP docked into the mCAR structure but not the inverse agonist androstenol. Paclitaxel per se increases the expression of CAR in cancer cells. At last, we analyzed the expression of CAR in two public independent studies from The Cancer Genome Atlas (TCGA) of Non Small Cell Lung Cancer (NSCLC). CAR is expressed in variable levels in NSCLC samples and no association with overall survival was noted. Conclusions/Significance Taken together, our results demonstrated that CAR agonists modulate the antineoplastic efficacy of paclitaxel in mouse and human cancer cell lines. This effect was probably related by the enhanced expression of two tumor suppressor genes, viz. WT1 and MGMT. Most of NSCLC cases present CAR gene expression turning it possible to speculate the use of CAR modulation by ligands along with Paclitaxel in NSCLC therapy. PMID:24959746

  4. Personalized Therapy for Generalized Lymphatic Anomaly/Gorham-Stout Disease With a Combination of Sunitinib and Taxol

    PubMed Central

    Rössler, Jochen; Saueressig, Ulrich; Kayser, Gian; von Winterfeld, Moritz

    2015-01-01

    The recently revised ISSVA classification approved in Melbourne in April 2014 recognizes generalized lymphatic anomaly and lymphatic malformation in Gorham-Stout disease. The 2 entities can overlap in presentation, as both are characterized by destructive lymphatic vessel invasion of the axial skeleton and surrounding soft tissues. At least at present, no standard therapeutic options exist, and due to the rarity of the disease, no clinical trials are available. We present 2 patients, 1 with generalized lymphatic anomaly and 1 with lymphatic malformation in Gorham-Stout disease, with severe exacerbation during puberty. The first child presented in florid pulmonary failure and pleural effusion, the other with severe pain due to bone destruction of the pelvis and inability to walk. Both were treated using individualized protocols. The manuscript describes the rationale for choosing sunitinib in combination with low-dose (metronomic) taxol. Both patients experienced clinical and radiologic response without major toxicities, suggesting that patients with rare conditions may benefit from individualized, molecularly based therapies. PMID:26458155

  5. In vitro synergistic efficacy of conjugated linoleic acid, oleic acid, safflower oil and taxol cytotoxicity on PC3 cells.

    PubMed

    K?z?l?ahin, Sadi; Nalbantsoy, Ay?e; Yava?o?lu, N lk Karabay

    2015-01-01

    The aim of this study was to determine in vitro synergistic efficacy of conjugated linoleic acid (CLA), oleic acid (OLA), safflower oil and taxol (Tax) cytotoxicity on human prostate cancer (PC3) cell line. To determine synergistic efficacy of oil combinations, PC3 treated with different doses of compounds alone and combined with 10 ?g/mL Tax. The MTT results indicated that OLA-Tax combinations exhibited cytotoxicity against PC3 at doses of 30 nM+10 ?g-Tax, 15 nM+5 ?g-Tax and 7.5 nM+2.5 ?g-Tax. The treatment of OLA or Tax did not show significant inhibition on PC3, while OLA-Tax combinations showed effective cytotoxicity at treated doses. CLA-Tax combinations demonstrated the same effect on PC3 as combined form with 45.72% versus the alone form as 74.51% viability. Cytotoxic synergy between Tax, OLA and CLA shows enhanced cytotoxicity on PC3 which might be used in the therapy of prostate cancer. PMID:25134457

  6. Nab-paclitaxel-induced cystoid macular edema in a patient with pre-existing optic neuropathy.

    PubMed

    Park, Elizabeth; Goldberg, Naomi R; Adams, Sylvia

    2016-07-01

    Paclitaxel is a widely used chemotherapy agent that has rarely been associated with ophthalmic toxicities. Cystoid macular edema is one such rare side effect of paclitaxel therapy. Its pathophysiology remains poorly understood. Here, we report on a 69-year-old woman who developed cystoid macular edema associated with the albumin-bound formulation of paclitaxel after several months of therapy for breast cancer. After 2 months of drug withdrawal, her vision improved and there was a significant improvement in the macular edema by imaging with spectral-domain optical coherence tomography. Oncologists using taxane agents should be aware of this rare adverse outcome for timely patient referral to an ophthalmologist and appropriate treatment to preserve a patient's visual acuity. PMID:26982237

  7. Poly-paclitaxel/cyclodextrin-SPION nano-assembly for magnetically guided drug delivery system.

    PubMed

    Jeon, Hyeonjeong; Kim, Jihoon; Lee, Yeong Mi; Kim, Jinhwan; Choi, Hyung Woo; Lee, Junseok; Park, Hyeongmok; Kang, Youngnam; Kim, In-San; Lee, Byung-Heon; Hoffman, Allan S; Kim, Won Jong

    2016-06-10

    This work demonstrates the development of magnetically guided drug delivery systems and its potential on efficient anticancer therapy. The magnetically guided drug delivery system was successfully developed by utilizing superparamagnetic iron oxide nanoparticle, β-cyclodextrin, and polymerized paclitaxel. Multivalent host-guest interactions between β-cyclodextrin-conjugated superparamagnetic iron oxide nanoparticle and polymerized paclitaxel allowed to load the paclitaxel and the nanoparticle into the nano-assembly. Clusterized superparamagnetic iron oxide nanoparticles in the nano-assembly permitted the rapid and efficient targeted drug delivery. Compared to the control groups, the developed nano-assembly showed the enhanced anticancer effects in vivo as well as in vitro. Consequently, the strategy of the use of superparamagnetic nanoparticles and multivalent host-guest interactions has a promising potential for developing the efficient drug delivery systems. PMID:26780174

  8. Metronomic oral paclitaxel shows anti-tumor effects in an orthotopic mouse model of ovarian cancer

    PubMed Central

    Hahn, Ho-Suap; Lee, Ki-Heon; Lee, In-Ho; Lee, Jae-Ho; Whang, Chang-Sung; Jo, Yeong-Woo

    2014-01-01

    Objective The purpose of this study was to compare the in vivo anti-tumor efficacy of a mucoadhesive, lipid-based, oral paclitaxel formulation (DHP107) with traditional, intraperitoneal (IP) paclitaxel using an orthotopic mouse model of chemotherapy-sensitive SKOV3ip1 ovarian cancer. Methods To determine the optimal therapeutic dose of oral paclitaxel, DHP107 was administered per os to female athymic nude mice at 0, 25, or 50 mg/kg twice per week. Control mice received 100 µL saline once per week. IP injections of paclitaxel at 5 mg/kg once per week were used for comparison. To evaluate the potential therapeutic effect of metronomic DHP107 chemotherapy, mice received DHP107 50 mg/kg once per week per os, which was compared with 25 mg/kg twice per week and with vehicle-treated controls. Results Low-dose DHP107 (25 mg/kg) twice per week was as effective as IP paclitaxel (5 mg/kg once a week) but high-dose DHP107 (50 mg/kg once per week) was less effective at inhibiting tumor growth in an orthotopic mouse model (88%, 82%, and 36% decrease in tumor weight, respectively). Mice that received 25 mg/kg DHP107 twice per week or 50 mg/kg DHP107 once per week per os had a significant decrease in tumor weight compared with vehicle-treated controls (p<0.01, both doses). Conclusion Metronomic oral chemotherapy with DHP107 showed anti-tumor efficacy in vivo similar to IP paclitaxel in an orthotopic mouse model. PMID:24761217

  9. Therapeutic efficacy of paclitaxel and carboplatin via arterial or venous perfusion in rabbits with VX-2 tongue cancer

    PubMed Central

    Zhang, Ni-Ni; Zhang, Li-Gang; Liu, Ze-Nian; Huang, Gui-Lin; Zhang, Lin; Yi, Jie; Yao, Li; Hu, Xiao-Hua

    2015-01-01

    Objective: This study aimed to investigate the therapeutic efficacy of paclitaxel in combination with carboplatin in different ways in rabbits with VX-2 tongue cancer. Methods: Rabbit VX-2 tongue cancer model was established and animals were then divided into 6 groups, in which animals received perfusion with paclitaxel liposome and carboplatin via the lingual artery, with free paclitaxel and carboplatin via the lingual artery, with 5% glucose via the lingual artery, with paclitaxel liposome and carboplatin via ear vein, with free paclitaxel and carboplatin via the ear vein and with 5% glucose via the ear vein independently. When the maximum diameter of cervical lymph nodes was larger than 5 mm, chemotherapy was initiated. Seven days later, flow cytometry and immunohistochemistry were performed to detect the apoptosis of VX-2 cells and P53 expression in the primary cancer and metastatic lymph nodes. Results: Targeted arterial perfusion with paclitaxel liposome in combination with carboplatin was more effective to induce the apoptosis of cancer cells in the primary cancer and metastatic lymph nodes and inhibit their proliferation. Conclusion: Targeted arterial perfusion with paclitaxel liposome in combination with carboplatin is effective to reduce tumor size, attenuate the surgery induced injury and improve the post-operative quality of life of oral cancer patients. PMID:26131070

  10. Phase II Study of Intraperitoneal Paclitaxel Plus Cisplatin and Intravenous Paclitaxel Plus Bevacizumab As Adjuvant Treatment of Optimal Stage II/III Epithelial Ovarian Cancer

    PubMed Central

    Konner, Jason A.; Grabon, Diana M.; Gerst, Scott R.; Iasonos, Alexia; Thaler, Howard; Pezzulli, Sandra D.; Sabbatini, Paul J.; Bell-McGuinn, Katherine M.; Tew, William P.; Hensley, Martee L.; Spriggs, David R.; Aghajanian, Carol A.

    2011-01-01

    Purpose Intraperitoneal (IP) cisplatin and intravenous (IV) or IP paclitaxel constitute a standard therapy for optimally debulked ovarian cancer. Bevacizumab prolongs progression-free survival (PFS) when included in first-line IV chemotherapy. In this study, the safety and feasibility of adding bevacizumab to a first-line IP regimen were assessed. Patients and Methods Treatment was as follows: paclitaxel 135 mg/m2 IV over 3 hours day 1, cisplatin 75 mg/m2 IP day 2, and paclitaxel 60 mg/m2 IP day 8. Bevacizumab 15 mg/kg IV was given after paclitaxel on day 1 beginning in cycle 2. After six cycles of chemotherapy, bevacizumab was given every 3 weeks for 17 additional treatments. The primary end point was safety and tolerability determined by whether 60% of patients completed six cycles of IV/IP chemotherapy. Results Of 41 treated patients, 30 (73%) received six cycles of IV/IP chemotherapy and 35 (85%) received at least four cycles. Three (27%) of those who discontinued chemotherapy did so because of complications related to bevacizumab (hypertension, n = 2; perforation, n = 1). Grades 3 to 4 toxicities included neutropenia (34%), vasovagal syncope (10%), hypertension (7%), nausea/vomiting (7%), hypomagnesemia (7%), and abdominal pain (7%). There were three grade 3 small bowel obstructions (7%) during cycles 3, 9, and 15. One patient died following rectosigmoid anastomotic dehiscence during cycle 4. Estimated median PFS is 28.6 months (95% CI, 19.1 to 38.9 months). Three patients (7%) had IP port malfunction. Conclusion The addition of bevacizumab to this IP regimen is feasible; however, bevacizumab may increase the risk of bowel obstruction/perforation. The observed median PFS is similar to that seen with IP/IV chemotherapy alone. PMID:22067389

  11. Liposomal cisplatin combined with paclitaxel versus cisplatin and paclitaxel in non-small-cell lung cancer: a randomized phase III multicenter trial

    PubMed Central

    Stathopoulos, G. P.; Antoniou, D.; Dimitroulis, J.; Michalopoulou, P.; Bastas, A.; Marosis, K.; Provata, A.; Yiamboudakis, P.; Veldekis, D.; Lolis, N.; Georgatou, N.; Toubis, M.; Pappas, Ch.; Tsoukalas, G.

    2010-01-01

    Background: Liposomal cisplatin is a new formulation developed to reduce the systemic toxicity of cisplatin while simultaneously improving the targeting of the drug to the primary tumor and to metastases by increasing circulation time in the body fluids and tissues. The primary objectives were to determine nephrotoxicity, gastrointestinal side-effects, peripheral neuropathy and hematological toxicity and secondary objectives were to determine the response rate, time to tumor progression (TTP) and survival. Patients and methods: Two hundred and thirty-six chemotherapy-naive patients with inoperable non-small-cell lung cancer were randomly allocated to receive either 200 mg/m2 of liposomal cisplatin and 135 mg/m2 paclitaxel (arm A) or 75 mg/m2 cisplatin and 135 mg/m2 paclitaxel (arm B), once every 2 weeks on an outpatient basis. Two hundred and twenty-nine patients were assessable for toxicity, response rate and survival. Nine treatment cycles were planned. Results: Arm A patients showed statistically significant lower nephrotoxicity, grade 3 and 4 leucopenia, grade 2 and 3 neuropathy, nausea, vomiting and fatigue. There was no significant difference in median and overall survival and TTP between the two arms; median survival was 9 and 10 months in arms A and B, respectively, and TTP was 6.5 and 6 months in arms A and B, respectively. Conclusions: Liposomal cisplatin in combination with paclitaxel has been shown to be much less toxic than the original cisplatin combined with paclitaxel. Nephrotoxicity in particular was negligible after liposomal cisplatin administration. TTP and survival were similar in both treatment arms. PMID:20439345

  12. Drug-drug Interaction between Losartan and Paclitaxel in Human Liver Microsomes with Different CYP2C8 Genotypes.

    PubMed

    Mukai, Yuji; Senda, Asuna; Toda, Takaki; Hayakawa, Toru; Eliasson, Erik; Rane, Anders; Inotsume, Nobuo

    2015-06-01

    The cytochrome P450 (CYP) 2C8*3 allele is associated with reduced metabolic activity of paclitaxel. This study was aimed to investigate the inhibitory effect of losartan on paclitaxel metabolism in human liver microsomes (HLMs) and to determine the impact of the CYP2C8*3 polymorphism. HLMs that contained the CYP2C8*1 homozygote (HL60) or CYP2C8*3 heterozygote (HL54) genotype were used for the inhibition study. Losartan, at a concentration of 50 μmol/L, significantly inhibited paclitaxel metabolism by 29% and 57% in the HL60 (p < 0.001) and HL54 (p < 0.01), respectively. When using HL60, losartan and the CYP3A4-selective inhibitors, erythromycin and ketoconazole, caused a greater inhibition of the paclitaxel metabolism than quercetin, a CYP2C8-selective inhibitor. This demonstrated that the paclitaxel metabolism was mainly catalysed by CYP3A4 in HL60. There were no significant differences found for the inhibitory effects caused by the four inhibitors of the paclitaxel metabolism in HL54, indicating that both CYP2C8 and CYP3A4 play important roles in paclitaxel metabolism in HL54. These findings suggest that 50 μmol/L of losartan inhibits both CYP2C8 and CYP3A4 in HLMs. In summary, losartan inhibited paclitaxel metabolism, with concentrations over 50 μmol/L in HLMs. The CYP2C8*3 allele carriers are likely susceptible to the interactions of losartan and CYP3A4 inhibitors to paclitaxel metabolism. PMID:25424246

  13. The Cancer Chemotherapeutic Paclitaxel Increases Human and Rodent Sensory Neuron Responses to TRPV1 by Activation of TLR4

    PubMed Central

    Li, Yan; Adamek, Pavel; Zhang, Haijun; Tatsui, Claudio Esteves; Rhines, Laurence D.; Mrozkova, Petra; Li, Qin; Kosturakis, Alyssa K.; Cassidy, Ryan M.; Harrison, Daniel S.; Cata, Juan P.; Sapire, Kenneth; Zhang, Hongmei; Kennamer-Chapman, Ross M.; Jawad, Abdul Basit; Ghetti, Andre; Yan, Jiusheng; Palecek, Jiri

    2015-01-01

    Peripheral neuropathy is dose limiting in paclitaxel cancer chemotherapy and can result in both acute pain during treatment and chronic persistent pain in cancer survivors. The hypothesis tested was that paclitaxel produces these adverse effects at least in part by sensitizing transient receptor potential vanilloid subtype 1 (TRPV1) through Toll-like receptor 4 (TLR4) signaling. The data show that paclitaxel-induced behavioral hypersensitivity is prevented and reversed by spinal administration of a TRPV1 antagonist. The number of TRPV1+ neurons is increased in the dorsal root ganglia (DRG) in paclitaxel-treated rats and is colocalized with TLR4 in rat and human DRG neurons. Cotreatment of rats with lipopolysaccharide from the photosynthetic bacterium Rhodobacter sphaeroides (LPS-RS), a TLR4 inhibitor, prevents the increase in numbers of TRPV1+ neurons by paclitaxel treatment. Perfusion of paclitaxel or the archetypal TLR4 agonist LPS activated both rat DRG and spinal neurons directly and produced acute sensitization of TRPV1 in both groups of cells via a TLR4-mediated mechanism. Paclitaxel and LPS sensitize TRPV1 in HEK293 cells stably expressing human TLR4 and transiently expressing human TRPV1. These physiological effects also are prevented by LPS-RS. Finally, paclitaxel activates and sensitizes TRPV1 responses directly in dissociated human DRG neurons. In summary, TLR4 was activated by paclitaxel and led to sensitization of TRPV1. This mechanism could contribute to paclitaxel-induced acute pain and chronic painful neuropathy. SIGNIFICANCE STATEMENT In this original work, it is shown for the first time that paclitaxel activates peripheral sensory and spinal neurons directly and sensitizes these cells to transient receptor potential vanilloid subtype 1 (TRPV1)-mediated capsaicin responses via Toll-like receptor 4 (TLR4) in multiple species. A direct functional interaction between TLR4 and TRPV1 is shown in rat and human dorsal root ganglion neurons, TLR4/TRPV1-coexpressing HEK293 cells, and in both rat and mouse spinal cord slices. Moreover, this is the first study to show that this interaction plays an important role in the generation of behavioral hypersensitivity in paclitaxel-related neuropathy. The key translational implications are that TLR4 and TRPV1 antagonists may be useful in the prevention and treatment of chemotherapy-induced peripheral neuropathy in humans. PMID:26424893

  14. Designing Paclitaxel Drug Delivery Systems Aimed at Improved Patient Outcomes: Current Status and Challenges

    PubMed Central

    Surapaneni, Madhu S.; Das, Sudip K.; Das, Nandita G.

    2012-01-01

    Paclitaxel is one of the most widely used and effective antineoplastic agents derived from natural sources. It has a wide spectrum of antitumor activity, particularly against ovarian cancer, breast cancer, nonsmall cell lung cancer, head and neck tumors, Kaposi's sarcoma, and urologic malignancies. It is a highly lipophilic compound with a log P value of 3.96 and very poor aqueous solubility of less than 0.01 mg/mL. In addition, the compound lacks functional groups that are ionizable which could potentially lead to an increase in its solubility with the alteration in pH. Therefore, the delivery of paclitaxel is associated with substantial challenges. Until the introduction of Abraxane, only commercial formulation was solution of paclitaxel in cremophor, which caused severe side effects. However, in recent years, a number of approaches have been reported to solubilize paclitaxel using cosolvents and inclusion complexes. In addition, innovative approaches have been reported for passive targeting of tumors using nanoparticles, nanosuspensions, liposomes, emulsions, micelles, implants, pastes and gels. All approaches for delivery of improved therapeutic outcome have been discussed in this paper. PMID:22934190

  15. Effect of Combined Treatment Using Wilfortrine and Paclitaxel in Liver Cancer and Related Mechanism

    PubMed Central

    Li, Shuzhen; Zheng, Lei

    2016-01-01

    Background Liver cancer is a common malignant tumor with high mortality. Currently, effective medicines against liver cancer are still lacking. Paclitaxel is a wide-spectrum anti-tumor agent, while wilfortrine has been shown to have an inhibitory effect on the proliferation of liver cancer cells. This study thus investigated the potential effect of paclitaxel combined with wilfortrine on cultured liver cancer cells and related mechanisms, in order to provide evidence for pathogenesis and treatment of liver cancer. Material/Methods Liver cancer cell line HpeG2 was divided into control, paclitaxel, wilfortrine, and combined treatment groups. Cell proliferation was tested by MTT, while invasion was detected in Transwell chamber assay. Apoptotic protein Bcl-2 and Bax expression levels were further quantified using real-time PCR and Western blotting. Results Both of those 2 drugs can effectively inhibit cancer cell proliferation, depress invasion ability, increase Bcl-2 expression, and elevate Bax expression levels (p<0.05 in all cases). The combined therapy had better treatment efficacy compared to either of those drugs alone (p<0.05). Conclusions The combined treatment using wilfortrine and paclitaxel can inhibit proliferation and invasion of liver cancer cells via down-regulating Bcl-2 and up-regulating Bax, with better efficacy than single use of either drug. PMID:27043783

  16. In vivo prevention of arterial restenosis with paclitaxel-encapsulated targeted lipid–polymeric nanoparticles

    PubMed Central

    Chan, Juliana M.; Drum, Chester L.; Bronson, Roderick T.; Golomb, Gershon; Langer, Robert; Farokhzad, Omid C.

    2011-01-01

    Following recent successes with percutaneous coronary intervention (PCI) for treating coronary artery disease (CAD), many challenges remain. In particular, mechanical injury from the procedure results in extensive endothelial denudation, exposing the underlying collagen IV-rich basal lamina, which promotes both intravascular thrombosis and smooth muscle proliferation. Previously, we reported the engineering of collagen IV-targeting nanoparticles (NPs) and demonstrated their preferential localization to sites of arterial injury. Here, we develop a systemically administered, targeted NP system to deliver an antiproliferative agent to injured vasculature. Approximately 60-nm lipid–polymeric NPs were surface functionalized with collagen IV-targeting peptides and loaded with paclitaxel. In safety studies, the targeted NPs showed no signs of toxicity and a ≥3.5-fold improved maximum tolerated dose versus paclitaxel. In efficacy studies using a rat carotid injury model, paclitaxel (0.3 mg/kg or 1 mg/kg) was i.v. administered postprocedure on days 0 and 5. The targeted NP group resulted in lower neointima-to-media (N/M) scores at 2 wk versus control groups of saline, paclitaxel, or nontargeted NPs. Compared with sham-injury groups, an ∼50% reduction in arterial stenosis was observed with targeted NP treatment. The combination of improved tolerability, sustained release, and vascular targeting could potentially provide a safe and efficacious option in the management of CAD. PMID:22087004

  17. [Effect of Scutellaria baicalensis root extract on cytogenetic damage induced by paclitaxel and cisplatin in mice].

    PubMed

    Neupokoeva, O V; Voronova, O L; Churin, A A; Suslov, N I; Shilova, I V; Kuzovkina, I N

    2013-01-01

    The effect of root extract of Baikal skullcap (Scutellaria baicalensis) cultivated in vitro, on the gene structure of CBA/CaLac mice bone marrow cells damaged by anticancer drugs paclitaxel and cisplatin has been studied. It is established that the root extract exhibits gene protective property upon both single and chronic administration. PMID:24605424

  18. In Vitro Activity of Paclitaxel-Loaded Polymeric Expansile Nanoparticles in Breast Cancer Cells

    PubMed Central

    Zubris, Kimberly Ann V.; Liu, Rong; Colby, Aaron; Schulz, Morgan D.; Colson, Yolonda L.; Grinstaff, Mark W.

    2013-01-01

    Through a series of in vitro studies, the essential steps for intracellular drug delivery of paclitaxel using a pH-responsive nanoparticle system have been investigated in breast cancer cells. We successfully encapsulated paclitaxel within polymeric expansile nanoparticles (Pax-eNPs) at 5% loading via a miniemulsion polymerization procedure. Fluorescently tagged eNPs were readily taken up by MDA-MB-231 breast cancer cells grown in culture as confirmed by confocal microscopy and flow cytometry. The ability of the encapsulated paclitaxel to reach the cytoplasm was also observed using confocal microscopy and fluorescently labeled paclitaxel. Pax-eNPs were shown to be efficacious against three in vitro human breast adenocarcinoma cell lines (MDA-MB-231, MCF-7 and SK-BR-3) as well as cells isolated from the pleural effusions of two different breast cancer patients. Lastly, macropinocytosis was identified as the major cellular pathway responsible for eNP uptake, as confirmed using temperature-sensitive metabolic reduction, pharmacologic inhibitors, and fluid-phase marker co-localization. PMID:23617223

  19. Release Kinetics of Paclitaxel and Cisplatin from Two and Three Layered Gold Nanoparticles

    PubMed Central

    England, Christopher G.; Miller, M. Clarke; Kuttan, Ashani; Trent, John O.; Frieboes, Hermann B.

    2015-01-01

    Gold nanoparticles functionalized with biologically-compatible layers may achieve stable drug release while avoiding adverse effects in cancer treatment. We study cisplatin and paclitaxel release from gold cores functionalized with hexadecanethiol (TL) and phosphatidylcholine (PC) to form two-layer nanoparticles, or TL, PC, and high density lipoprotein (HDL) to form three-layer nanoparticles. Drug release was monitored for 14 days to assess long term effects of the core surface modifications on release kinetics. Release profiles were fitted to previously developed kinetic models to differentiate possible release mechanisms. The hydrophilic drug (cisplatin) showed an initial (5-hr.) burst, followed by a steady release over 14 days. The hydrophobic drug (paclitaxel) showed a steady release over the same time period. Two layer nanoparticles released 64.0 ± 2.5% of cisplatin and 22.3 ± 1.5% of paclitaxel, while three layer nanoparticles released the entire encapsulated drug. The Korsmeyer-Peppas model best described each release scenario, while the simplified Higuchi model also adequately described paclitaxel release from the two layer formulation. We conclude that functionalization of gold nanoparticles with a combination of TL and PC may help to modulate both hydrophilic and hydrophobic drug release kinetics, while the addition of HDL may enhance long term release of hydrophobic drug. PMID:25753197

  20. Photoimmunotherapy of hepatocellular carcinoma-targeting Glypican-3 combined with nanosized albumin-bound paclitaxel

    PubMed Central

    Hanaoka, Hirofumi; Nakajima, Takahito; Sato, Kazuhide; Watanabe, Rira; Phung, Yen; Gao, Wei; Harada, Toshiko; Kim, Insook; Paik, Chang H; Choyke, Peter L; Ho, Mitchell; Kobayashi, Hisataka

    2015-01-01

    Aim Effectiveness of Glypican-3 (GPC3)-targeted photoimmunotherapy (PIT) combined with the nanoparticle albumin-bound paclitaxel (nab-paclitaxel) for hepatocellular carcinoma was evaluated. Materials & methods GPC3 expressing A431/G1 cells were incubated with a phthalocyanine-derivative, IRDye700DX (IR700), conjugated to an anti-GPC3 antibody, IR700-YP7 and exposed to near-infrared light. Therapeutic experiments combining GPC3-targeted PIT with nab-paclitaxel were performed in A431/G1 tumor-bearing mice. Results IR700-YP7 bound to A431/G1 cells and induced rapid target-specific necrotic cell death by near-infrared light exposure in vitro. IR700-YP7 accumulated in A431/G1 tumors. Tumor growth was inhibited by PIT compared with nontreated control. Additionally, PIT dramatically increased nabpaclitaxel delivery and enhanced the therapeutic effect. Conclusion PIT targeting GPC3 combined with nab-paclitaxel is a promising method for treating hepatocellular carcinoma. PMID:25929570

  1. Gemcitabine in combination with paclitaxel for advanced soft-tissue sarcomas

    PubMed Central

    SONNENBLICK, AMIR; ELEYAN, FERAS; PERETZ, TAMAR; OSPOVAT, INNA; MERIMSKY, OFER; SELLA, TAMAR; PEYLAN-RAMU, NILI; KATZ, DANIELA

    2015-01-01

    A limited number of chemotherapeutic agents have been found to be active against advanced soft-tissue sarcomas (STSs), particularly sarcomas that have progressed following doxorubicin treatment. The aim of this retrospective study was to determine the response to treatment with gemcitabine plus paclitaxel in patients with STSs. Data were collected on all patients with advanced non-resectable STS who were treated with a fixed dose 700 mg/m2 gemcitabine in combination with 70 mg/m2 paclitaxel on days 1 and 8 every 3 weeks. A total of 30 patients were included, with a median age of 56.4 years (range, 40–70 years). The gemcitabine/paclitaxel combination was well tolerated, with an overall response in 27% and a clinical benefit in 57% of the patients. The median progression-free survival was 6.1 months and the overall survival was 14.3 months. In conclusion, gemcitabine plus paclitaxel was found to be tolerable and effective in patients with advanced STSs. PMID:26171190

  2. A process optimization study on ultrasonic extraction of paclitaxel from Taxus cuspidata.

    PubMed

    Wang, Shujie; Li, Chun; Wang, Hujun; Zhong, Xiangmei; Zhao, Jing; Zhou, Yajun

    2016-04-01

    This study aimed to improve the extraction rate of paclitaxel from Taxus cuspidata in order to determine the most effective combination of ultrasonic extraction and thin-layer chromatography-ultraviolet (TLC-UV) rapid separation method. The study was performed using the Box-Behnken test design to conduct single-factor experiments using ultrasonic extraction of paclitaxel from Taxus cuspidata. The study showed ethanol to be the best extraction solvent. When mixed with dichloromethane (1:1), the ratio of material to liquid was 1:50 when using an ultrasonic time of 1 hr at a power of 200 W. The correction coefficient K for the separation and detection of paclitaxel using the TLC-UV spectrophotometric method was 0.009152. Multifactor experiments determined the effect of the rate of liquid to material (X1), ultrasonic time (X2), and ultrasonic power (X3) on extraction using extraction volume as the dependent variable. Response surface analysis allowed a regression equation to be obtained, with the optimal conditions for extraction when the rate of liquid to material was 53.23 mL/g as an ultrasonic time of 1.11 hr and an ultrasonic power of 207.88 W. Using these parameters, the average amount of extracted paclitaxel was about 130.576 µg/g, which was significantly better than for other extraction methods. PMID:25830908

  3. Phase II trial of weekly nab-paclitaxel and carboplatin treatment with or without trastuzumab as nonanthracycline neoadjuvant chemotherapy for locally advanced breast cancer

    PubMed Central

    Huang, Liang; Chen, Sheng; Yao, Ling; Liu, Guangyu; Wu, Jiong; Shao, Zhiming

    2015-01-01

    Background Neoadjuvant chemotherapy has become standard treatment for women with locally advanced breast cancer. The aim of this study was to compare the efficacy and safety of nanoparticle albumin-bound paclitaxel (nab-paclitaxel) versus paclitaxel combined with carboplatin. Methods Thirty patients were treated with neoadjuvant nab-paclitaxel (125 mg/m2, days 1, 8, and 15) and carboplatin (area under the curve =2; days 1, 8, and 15) every 21 days for four cycles. Ninety matched patients received paclitaxel (80 mg/m2, days 1, 8, and 15) and carboplatin every 21 days for four cycles. Weekly trastuzumab is recommended for overexpression of human epidermal receptor-2. The primary endpoint was pathologic complete response (defined as ypT0/is ypN0). Matching was conducted according to six variables: body mass index, clinical tumor stage, clinical lymph node status, estrogen receptor status, HER2 status, and trastuzumab receiving rate. Results Ninety percent of patients in the nab-paclitaxel group and 80% of patients in the paclitaxel group experienced a clinical objective response (complete response or partial response; P=0.450). Eight patients in the nab-paclitaxel group and 23 patients in the paclitaxel group had a pathologic complete response in the breast and axillary nodes (26.7% versus 25.6%; P=0.904). Nab-paclitaxel showed a beneficial effective trend on clinical tumor stage II (36.8% versus 15.8%; P=0.051). When trastuzumab was added to nab-paclitaxel, the pathologic complete response rate was not significantly improved more than with trastuzumab and paclitaxel (43.6% versus 39.6%; P=0.769). Carboplatin plus nab-paclitaxel or paclitaxel had similarly low pathologic complete response rates (7.7% versus 10.5%) for the luminal molecular subtype. One (50%) triple-negative patient achieved a pathologic complete response. The nab-paclitaxel regimen caused more grade 4 neutropenia than the paclitaxel regimen (56.7% versus 21.1%; P<0.001). Conclusion Our study shows that weekly nab-paclitaxel and carboplatin with or without trastuzumab resulted in a pathologic complete response rate that was not superior to the matched cohorts. Future, larger trials are needed to validate that nab-paclitaxel is beneficial for clinical tumor stage II and the triple-negative subgroup. PMID:25792830

  4. Polymeric nanoparticles for the intracellular delivery of paclitaxel in lung and breast cancer

    NASA Astrophysics Data System (ADS)

    Zubris, Kimberly Ann Veronica

    Nanoparticles are useful for addressing many of the difficulties encountered when administering therapeutic compounds. Nanoparticles are able to increase the solubility of hydrophobic drugs, improve pharmacokinetics through sustained release, alter biodistribution, protect sensitive drugs from low pH environments or enzymatic alteration, and, in some cases, provide targeting of the drug to the desired tissues. The use of functional nanocarriers can also provide controlled intracellular delivery of a drug. To this end, we have developed functional pH-responsive expansile nanoparticles for the intracellular delivery of paclitaxel. The pH-responsiveness of these nanoparticles occurs due to a hydrophobic to hydrophilic transition of the polymer occurring under mildly acidic conditions. These polymeric nanoparticles were systematically evaluated for the delivery of paclitaxel in vitro and in vivo to improve local therapy for lung and breast cancers. Nanoparticles were synthesized using a miniemulsion polymerization process and were subsequently characterized and found to swell when exposed to acidic environments. Paclitaxel was successfully encapsulated within the nanoparticles, and the particles exhibited drug release at pH 5 but not at pH 7.4. In addition, the uptake of nanoparticles was observed using flow cytometry, and the anticancer efficacy of the paclitaxel-loaded nanoparticles was measured using cancer cell lines in vitro. The potency of the paclitaxel-loaded nanoparticles was close to that of free drug, demonstrating that the drug was effectively delivered by the particles and that the particles could act as an intracellular drug depot. Following in vitro characterization, murine in vivo studies demonstrated the ability of the paclitaxel-loaded responsive nanoparticles to delay recurrence of lung cancer and to prevent establishment of breast cancer in the mammary fat pads with higher efficacy than paclitaxel alone. In addition, the ability of nanoparticles to migrate up to 40 cm through lymphatic channels to local lymph nodes was demonstrated using near infrared imaging in a large animal model. Continued investigation of functional nanoparticles, like the system described here for lung and breast cancer, will facilitate the development of new materials that meet the varied and demanding needs in chemotherapy, and may afford new treatment options for the local and metastatic control of many forms of cancer.

  5. Thermosensitive and Mucoadhesive Sol-Gel Composites of Paclitaxel/Dimethyl-β-Cyclodextrin for Buccal Delivery

    PubMed Central

    Kang, Bong-Seok; Ng, Choon Lian; Davaa, Enkhzaya; Park, Jeong-Sook

    2014-01-01

    The purpose of this study was to develop a buccal paclitaxel delivery system using the thermosensitive polymer Pluronic F127 (PF127) and the mucoadhesive polymer polyethylene oxide (PEO). The anticancer agent paclitaxel is usually used to treat ovarian, breast, and non-small-cell lung cancer. To improve its aqueous solubility, paclitaxel was incorporated into an inclusion complex with (2,6-di-O-methyl)-β-cyclodextrin (DMβCD). The formation of the paclitaxel inclusion complex was evaluated using various techniques, including x-ray diffractometry (XRD), Fourier-transform infrared (FT-IR) spectrophotometry, differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Hydrogels were prepared using a cold method. Concentrations of 18, 20, and 23% (w/v) PF127 were dissolved in distilled water including paclitaxel and stored overnight in a refrigerator at 4°C. PEO was added at concentrations of 0.1, 0.2, 0.4, 0.8, and 1% (w/v). Each formulation included paclitaxel (0.5 mg/mL). The sol-gel transition temperature of the hydrogels was measured using the tube-inverting method. Drug release from the hydrogels was measured using a Franz diffusion cell containing pH 7.4 phosphate-buffered solution (PBS) buffer at 37°C. The cytotoxicity of each formulation was measured using the MTT assay with a human oral cancer cell (KB cell). The sol-gel transition temperature of the hydrogel decreased when PF127 was present and varied according to the presence of mucoadhesive polymers. The in vitro release was sustained and the release rate was slowed by the addition of the mucoadhesive polymer. The cytotoxicity of the blank formulation was low, although the drug-loaded hydrogel showed acceptable cytotoxicity. The results of our study suggest that the combination of a PF 127-based mucoadhesive hydrogel formulation and inclusion complexes improves the in vitro release and cytotoxic effect of paclitaxel. PMID:25275485

  6. Paclitaxel Loaded Nanoliposomes in Thermosensitive Hydrogel: A Dual Approach for Sustained and Localized Delivery.

    PubMed

    Mahajan, Mohit; Utreja, Puneet; Jain, Subheet Kumar

    2016-01-01

    In an attempt to improve the localized paclitaxel delivery, carrier based thermoresponsive chitosan hydrogel was exploited in the present study. Nanoliposomes as carrier for paclitaxel were prepared and optimized in strength of 6 mg/ml similar to marketed paclitaxel formulation. The chitosan solution (2% w/v) mixed with different concentrations of dibasic sodium phosphate (DSP) was evaluated as thermoresponsive systems in terms of gelling temperature and time. Finally, the drug loaded nanoliposomes were incorporated in optimized chitosan- DSP hydrogel base to form nanoliposomal in situ thermosensitive hydrogel formulations having dual mechanism of protection and release. The optimal formulation containing DSP was selected on the basis of minimal gelation temperature (37±0.8 ºC) and time (6.7±0.3 min). In vitro drug release experiment illustrated that developed formulation manifested sustained release action in which drug release was extended for more than 72 h compared to marketed formulation. In addition, optimized nanoliposomal hydrogel demonstrated enhanced biological half-life of 15.7±1.5h, depicting maintenance of constant plasma concentration in contrast to marketed formulation that showed the half-life (t1/2) of 3.6±0.4h. The in vivo anti tumor activity tested using EAC model also corroborated the above findings that developed formulation was having significant higher anti-tumor activity and reduced toxicity than the marketed formulation. Tumor volume was found to reduce upto 89.1±3.5% by treatment with in situ hydrogel formulation. The histopathological study of tumor also demonstrated the better safety and efficacy of developed formulation in comparison to marketed paclitaxel formulation. Our results suggest that carrier based chitosan hydrogel could be an efficacious vehicle for sustained and localized delivery of paclitaxel. PMID:26255673

  7. Chronic cannabinoid CB2 activation reverses paclitaxel neuropathy without tolerance or CB1-dependent withdrawal

    PubMed Central

    Deng, Liting; Guindon, Josée; Cornett, Benjamin L.; Makriyannis, Alexandros; Mackie, Ken; Hohmann, Andrea G.

    2014-01-01

    Background Mixed cannabinoid CB1/CB2 agonists such as Δ9-tetrahydrocannabinol (Δ9-THC) can produce tolerance, physical withdrawal, and unwanted CB1-mediated central nervous system side effects. Whether repeated systemic administration of a CB2-preferring agonist engages CB1 receptors or produces CB1-mediated side effects is unknown. Methods We evaluated anti-allodynic efficacy, possible tolerance, and cannabimimetic side effects of repeated dosing with a CB2-preferring agonist AM1710 in a model of chemotherapy-induced neuropathy produced by paclitaxel using CB1KO, CB2KO, and WT mice. Comparisons were made with the prototypic classical cannabinoid Δ9-THC. We also explored the site and possible mechanism of action of AM1710. Results Paclitaxel-induced mechanical and cold allodynia developed equivalently in CB1KO, CB2KO, and WT mice. Both AM1710 and Δ9-THC suppressed established paclitaxel-induced allodynia in WT mice. Unlike Δ9-THC, chronic AM1710 did not engage CB1 activity or produce antinociceptive tolerance, CB1-mediated cannabinoid withdrawal, hypothermia, or motor dysfunction. Anti-allodynic efficacy of systemic AM1710 was absent in CB2KO mice or WT mice receiving the CB2 antagonist AM630, administered either systemically or intrathecally. Intrathecal AM1710 also attenuated paclitaxel-induced allodynia in WT but not CB2KO mice, implicating a possible role for spinal CB2 receptors in AM1710 anti-allodynic efficacy. Finally, both acute and chronic treatment with AM1710 decreased mRNA levels of tumor necrosis factor alpha and monocyte chemoattractant protein-1 in lumbar spinal cord of paclitaxel-treated WT mice. Conclusions Our results highlight the potential of prolonged use of CB2 agonists for managing chemotherapy-induced allodynia with a favorable therapeutic ratio marked by sustained efficacy and absence of tolerance, physical withdrawal, or CB1-mediated side effects. PMID:24853387

  8. C-MYC modulation induces responsiveness to paclitaxel in adrenocortical cancer cell lines.

    PubMed

    Cerquetti, Lidia; Sampaoli, Camilla; De Salvo, Maria; Bucci, Barbara; Argese, Nicola; Chimento, Adele; Vottari, Sebastiano; Marchese, Rodolfo; Pezzi, Vincenzo; Toscano, Vincenzo; Stigliano, Antonio

    2015-05-01

    C-MYC is overexpressed in many types of cancer linked to poor prognosis. We examined the c-Myc protein expression in adrenocortical cancer (ACC) cells to investigate the role of this protein in the neoplasm, its involvement in chemotherapy and finally to determine whether c-Myc could be considered a prognostic factor in patients with ACC. H295R and SW13 cell lines were treated with paclitaxel. c-Myc overexpressing cell clones were achieved by transfecting the H295R cell line with the pcDNA3-hMYC plasmid expressing the full-lengh C-MYC coding sequence. The SW13 cell line was transfected with siRNA oligonucleotides for C-MYC. Cell cycle analysis was evaluated by flow cytometry. c-Myc, cyclin B1 and pro caspase expression levels were evaluated by western blot analysis. We found that expression of c-Myc was highly expressed in the SW13 cells, whereas the protein was undetectable in the H295R cells. Different doses of paclitaxel were required in the two ACC cell line to induce a block in the G2 phase, characterized by increased cyclin B1 levels and to induce apoptosis by pro-caspase-3 activation. Interestingly, the silencing of C-MYC mRNA prevented paclitaxel induced apoptosis in SW13 cells, whereas in the H295R cells the overexpression of C-MYC rendered the cells more prone to growth inhibition after paclitaxel exposure. The present study directly demonstrates that C-MYC plays a central role in controlling proliferation in ACC cells after paclitaxel treatment and that c-Myc could be considered as a marker for predicting response to chemotherapeutic agents in ACC cell lines. PMID:25708932

  9. Comparative Effects of Ibandronate and Paclitaxel on Immunocompetent Bone Metastasis Model

    PubMed Central

    Chung, Yoon-Sok; Kang, Ho Chul

    2015-01-01

    Purpose Bone metastasis invariably increases morbidity and mortality. This study compares the effects of ibandronate and paclitaxel on bone structure and its mechanical properties and biochemical turnover in resorption markers using an immunocompetent Walker 256-Sprague-Dawley model, which was subjected to tumor-induced osteolysis. Materials and Methods Seventy rats were divided equally into 4 groups: 1) sham group (SHAM), 2) tumor group (CANC), 3) ibandronate treated group (IBAN), and 4) paclitaxel treated group (PAC). Morphological indices [bone volume fraction (BV/TV), trabecular number (Tb.N), trabecular thickness (Tb.Th), trabecular separation (Tb.Sp)] and mechanical properties (failure load, stiffness) were evaluated after thirty days of treatment period. Bone resorption rate was analysed using serum deoxypyridinoline (Dpd) concentrations. Results Morphological indices showed that ibandronate (anti-resorptive drug) had a better effect in treating tumor-induced architectural changes in bone than paclitaxel (chemotherapeutic drug). The deterioration in bone architecture was reflected in the biomechanical properties of bone as studied with decreased failure load (Fx) and stiffness (S) of the bone on the 30th day post-surgery. Dpd concentrations were significantly lower in the IBAN group, indicating successful inhibition of bone resorption and destruction. Conclusion Ibandronate was found to be as effective as higher doses of paclitaxel in maintaining stiffness of bone. Paclitaxel treatment did not appear to inhibit osteoclast resorption, which is contrary to earlier in-vitro literature. Emphasis should be placed on the use of immunocompetent models for examining drug efficacy since it adequately reflects bone metastasis in clinical scenarios. PMID:26446649

  10. A Randomized Phase III Trial of IV Carboplatin and Paclitaxel x 3 Courses Followed by Observation Versus Weekly Maintenance Low Dose Paclitaxel in Patients with Early Stage Ovarian Carcinoma: a Gynecologic Oncology Group Study

    PubMed Central

    Mannel, Robert S; Brady, Mark F; Kohn, Elise C.; Hanjani, Parviz; Hiura, Masamichi; Lee, Roger; DeGeest, Koen; Cohn, David E; Monk, Bradley J.; Michael, Helen

    2011-01-01

    Purpose To compare the recurrence-free interval (RFI), and safety profile in patients with completely resected high-risk early-stage ovarian cancer patients treated with intravenous (IV) carboplatin and paclitaxel with or without maintenance low-dose paclitaxel for 24 weeks. Methods Eligibility was limited to patients with Stage I-A/B (Grade 3 or clear cell), all I-C or II epithelial ovarian cancer. All patients were to receive carboplatin AUC 6 and paclitaxel 175 mg/m2 q 3 wks × 3 courses with random assignment to either observation or maintenance paclitaxel 40 mg/m2/wk × 24 wks. Recurrence required clinical or radiological evidence of new tumor. Results There were 571 patients enrolled onto this study, of whom 29 were deemed ineligible due to inappropriate stage or pathology, leaving 542 patients. At least 3 cycles of treatment were administered to 524/542 (97%) of patients, and among those assigned to maintenance paclitaxel, 80% completed the regimen. The incidence of grade 2 or worse peripheral neuropathy (15.5% vs 6%), infection/fever (19.9% vs 8.7%), and dermatologic events (70.8% vs 52.1%) were higher on the maintenance regimen (p<0.001). The cumulative probability of recurring within 5 years for the maintenance paclitaxel regimen is 20% vs. 23% for surveillance (hazard ratio 0.807; 95% CI: 0.565–1.15). The probability of surviving 5 years was 85.4% and 86.2%, respectively. Conclusion Maintenance paclitaxel at 40 mg/m2/wk × 24 wks added to standard dose AUC6 and paclitaxel 175 mg/m2 × 3 doses provides no significant increase in RFI. PMID:21529904

  11. In vitro and in vivo anticancer activity of surface modified paclitaxel attached hydroxyapatite and titanium dioxide nanoparticles.

    PubMed

    Venkatasubbu, G Devanand; Ramasamy, S; Reddy, G Pramod; Kumar, J

    2013-08-01

    Targeted drug delivery using nanocrystalline materials delivers the drug at the diseased site. This increases the efficacy of the drug in killing the cancer cells. Surface modifications were done to target the drug to a particular receptor on the cell surface. This paper reports synthesis of hydroxyapatite and titanium dioxide nanoparticles and modification of their surface with polyethylene glycol (PEG) followed by folic acid (FA). Paclitaxel, an anticancer drug, is attached to functionalized hydroxyapatite and titanium dioxide nanoparticles. The pure and functionalised nanoparticles are characterised with XRD, TEM and UV spectroscopy. Anticancer analysis was carried out in DEN induced hepatocarcinoma animals. Biochemical, hematological and histopathological analysis show that the surface modified paclitaxel attached nanoparticles have an higher anticancer activity than the pure paclitaxel and surface modified nanoparticles without paclitaxel. This is due to the targeting of the drug to the folate receptor in the cancer cells. PMID:23615724

  12. Paclitaxel-incorporated nanoparticles using block copolymers composed of poly(ethylene glycol)/poly(3-hydroxyoctanoate)

    PubMed Central

    2014-01-01

    Block copolymers composed of poly(3-hydroxyoctanoate) (PHO) and methoxy poly(ethylene glycol) (PEG) were synthesized to prepare paclitaxel-incorporated nanoparticle for antitumor drug delivery. In a 1H-NMR study, chemical structures of PHO/PEG block copolymers were confirmed and their molecular weight (M.W.) was analyzed with gel permeation chromatography (GPC). Paclitaxel as a model anticancer drug was incorporated into the nanoparticles of PHO/PEG block copolymer. They have spherical shapes and their particle sizes were less than 100 nm. In a 1H-NMR study in D2O, specific peaks of PEG solely appeared while peaks of PHO disappeared, indicating that nanoparticles have core-shell structures. The higher M.W. of PEG decreased loading efficiency and particle size. The higher drug feeding increased drug contents and average size of nanoparticles. In the drug release study, the higher M.W. of PEG block induced the acceleration of drug release rate. The increase in drug contents induced the slow release rate of drug. In an antitumor activity study in vitro, paclitaxel nanoparticles have practically similar anti-proliferation activity against HCT116 human colon carcinoma cells. In an in vivo animal study using HCT116 colon carcinoma cell-bearing mice, paclitaxel nanoparticles have enhanced antitumor activity compared to paclitaxel itself. Therefore, paclitaxel-incorporated nanoparticles of PHO/PEG block copolymer are a promising vehicle for antitumor drug delivery. PMID:25288916

  13. Monitoring Apoptosis of Breast Cancer Xenograft After Paclitaxel Treatment With 99mTc-Labeled Duramycin SPECT/CT.

    PubMed

    Luo, Rui; Niu, Lei; Qiu, Fan; Fang, Wei; Fu, Tong; Zhao, Ming; Zhang, Ying-Jian; Hua, Zi-Chun; Li, Xiao-Feng; Wang, Feng

    2016-01-01

    Our goal was to validate the feasibility of(99m)Tc-duramycin as a potential apoptosis probe for monitoring tumor response to paclitaxel in breast cancer xenografts. The binding of(99m)Tc-duramycin to phosphatidylethanolamine was validated in vitro using paclitaxel-treated human breast carcinoma MDA-MB-231 cells. Female BALB/c mice (n = 5) bearing breast cancer xenografts were randomized into 2 groups and intraperitoneally injected with 40 mg/kg paclitaxel or phosphate-buffered saline.(99m)Tc-duramycin (37-55.5 MBq) was injected at 72 hours posttreatment, and single-photon emission computed tomography/computed tomography was performed at 2 hours postinjection. Apoptotic cells and activated caspase 3 in explanted tumor tissue were measured by flow cytometry. Cellular ultrastructural changes were assessed by light and transmission electron microscopy.(99m)Tc-duramycin with radiochemical purity of >90% exhibited rapid blood clearance and predominantly renal clearance. The tumor-to-muscle ratio in the paclitaxel-treated group (5.29 ± 0.62) was significantly higher than that in the control. Tumor volume was decreased dramatically, whereas tumor uptake of(99m)Tc-duramycin (ex vivo) significantly increased following paclitaxel treatment, which was consistent with apoptotic index, histological findings, and ultrastructural changes. Our data demonstrated the feasibility of(99m)Tc-duramycin for early detection of apoptosis after paclitaxel chemotherapy in breast carcinoma xenografts. PMID:27030401

  14. Schedule-dependent synergism of taxol or taxotere with edatrexate against human breast cancer cells in vitro.

    PubMed

    Chou, T C; Otter, G M; Sirotnak, F M

    1996-01-01

    A new dihydrofolate reductase inhibitor, edatrexate (EDX), and the microtubule polymerization promotor, taxol (TXL) or taxotere (TXT), each have significant therapeutic activity against human breast cancer in clinical trials. Since they also have distinctly different mechanisms of actions and have mainly non-overlapping toxicities, they may be effective in combination in the treatment of this disorder. Schedule-dependent interactions between these taxanes and EDX against human breast adenocarcinoma cells (SK-Br-3) were quantitatively assessed in vitro to determine whether these interactions are synergistic or antagonistic. SK-Br-3 cells were grown as a monolayer in 96-well microplates. The dose-effect relationships of the drugs, singly and in combination, in inhibiting the growth over a 7-day period were determined by the SRB protein staining assays. Cell cultures were exposed to drug as a 3-h pulse at either 0-3 h or 24-27 h. Synergism or antagonism at different concentrations and at different effect levels were assessed with the median effect principle and the combination index-isobologram method using computer software. These methods were selected because they take into account both the potencies and the shape of the dose-effect curves. Exposure of cells to an equimolar combination of EDX + TXL (0-3 h) resulted in synergism at high effect levels. Pretreatment of cells with EDX (0-3 h) followed by TXL (24-27 h) showed even greater synergism in inhibiting cell growth. Moderate antagonism was observed with the reverse schedule. EDX + TXT (0-3 h) was additive, but pretreatment with EDX (0-3 hr) followed by TXT (24-27 h) showed synergism. However, the reverse order showed antagonism. Studies on another breast tumor cell line, ZR-57-1, also showed the schedule of EDX (0-3 h) + TXT or TXL (24-27 h) to be more synergistic than, the other two schedules examined. These results show potent schedule-dependent synergism of the combinations of TXL or TXT with EDX, and should form a rationale for designing clinical protocols utilizing these agents particularly for the treatment of breast cancer patients. PMID:8529281

  15. Phase II trial of capecitabine plus nab-paclitaxel in patients with metastatic pancreatic adenocarcinoma

    PubMed Central

    Kornek, Gabriela; Prager, Gerald; Stranzl, Nadja; Laengle, Friedrich; Schindl, Martin; Friedl, Josef; Klech, Julia; Roethlin, Sabine; Zielinski, Christoph

    2016-01-01

    Background Combination chemotherapy regimens including fluoropyrimidines as well as albumin-bound paclitaxel have shown promising results in patients with metastatic pancreatic adenocarcinoma (mPC). Based on the recently described excellent therapeutic index of capecitabine plus nab-paclitaxel in metastatic breast cancer, the present phase II trial was initiated. Methods Patients with previously untreated mPC were treated with capecitabine (825 mg/m2 orally bid on days 1-15) and nab-paclitaxel (125 mg/m2 intravenously on days 1 and 8) every 3 weeks. In patients without clinically relevant adverse reactions after the 1st treatment course (≤ grade 2 toxicities according to NCI-CTC vs. 4.0, exuding alopecia and fatigue of any degree) and adequate bone marrow function, the nab-paclitaxel dose was escalated to 100 mg/m2 on days 1, 8 and 15 of each cycle; this intra-individual dose escalation was maintained during subsequent treatment courses if tolerated. The primary endpoint was objective response rate (ORR) according to RECIST criteria, assessed by an independent radiological review committee with evaluation performed every 2 months. Results Between 12/2013 and 01/2015, 30 patients were entered in this monocentric academic phase II trial. All patients had an ECOG performance status of 0-1, 80% had liver metastases and 23% had biliary stents in place at time of study initiation. Median CA19-9 was 1,004 U/mL (0.9-100.000 U/mL). In all patients except 2, a dose escalation of nab-paclitaxel after the 1st treatment course could be accomplished. The most common grade 3 adverse events (AEs) included transient sensory neuropathy (23%), (afebrile) neutropenia (17%), hand-foot-syndrome (13%) and phototoxic skin reaction (10%). Among 29 RECIST-response assessable patients, the ORR was 41.4% and stable disease (SD) was noted in 34.5%, resulting in a disease control rate (DCR) of 76%. After a median follow-up duration of 10.3 months (range, 1.9-19.0 months), 13/30 patients (43.3%) are presently being alive. Conclusions The combination of capecitabine + nab-paclitaxel at these doses and scheduling was well tolerated and showed substantial antitumor efficacy. PMID:27034791

  16. Combinatorial TGF-β attenuation with paclitaxel inhibits the epithelial-to-mesenchymal transition and breast cancer stem-like cells

    PubMed Central

    Park, So-Yeon; Kim, Min-Jin; Park, Sang-A; Kim, Jung-Shin; Min, Kyung-Nan; Kim, Dae-Kee; Lim, Woosung; Nam, Jeong-Seok; Sheen, Yhun Yhong

    2015-01-01

    Distant relapse after chemotherapy is an important clinical issue for treating breast cancer patients and results from the development of cancer stem-like cells (CSCs) during chemotherapy. Here we report that blocking epithelial-to-mesenchymal transition (EMT) suppresses paclitaxel-induced CSCs properties by using a MDA-MB-231-xenografted mice model (in vivo), and breast cancer cell lines (in vitro). Paclitaxel, one of the cytotoxic taxane-drugs such as docetaxel, increases mesenchymal markers (Vimentin and Fibronectin) and decreases an epithelial marker (Zo-1). Blocking TGF-β signaling with the TGF-β type I receptor kinase (ALK5) inhibitor, EW-7197, suppresses paclitaxel-induced EMT and CSC properties such as mammosphere-forming efficiency (MSFE), aldehyde dehydrogenase (ALDH) activity, CD44+/CD24− ratio, and pluripotency regulators (Oct4, Nanog, Klf4, Myc, and Sox2). The combinatorial treatment of EW-7197 improves the therapeutic effect of paclitaxel by decreasing the lung metastasis and increasing the survival time in vivo. We confirmed that Snail is increased by paclitaxel-induced intracellular reactive oxygen species (ROS) and EW-7197 suppresses the paclitaxel-induced Snail and EMT by attenuating paclitaxel-induced intracellular ROS. Knock-down of SNAI1 suppresses paclitaxel-induced EMT and CSC properties. These data together suggest that blocking the Snail-induced EMT with the ALK5 inhibitor attenuates metastasis after paclitaxel-therapy and that this combinatorial approach could prove useful in treating breast cancer. PMID:26462028

  17. Macitentan (ACT-064992), a tissue-targeting endothelin receptor antagonist, enhances therapeutic efficacy of paclitaxel by modulating survival pathways in orthotopic models of metastatic human ovarian cancer.

    PubMed

    Kim, Sun-Jin; Kim, Jang Seong; Kim, Seung Wook; Brantley, Emily; Yun, Seok Joong; He, Junqin; Maya, Marva; Zhang, Fahao; Wu, Qiuyu; Lehembre, François; Regenass, Urs; Fidler, Isaiah J

    2011-02-01

    Potential treatments for ovarian cancers that have become resistant to standard chemotherapies include modulators of tumor cell survival, such as endothelin receptor (ETR) antagonist. We investigated the therapeutic efficacy of the dual ETR antagonist, macitentan, on human ovarian cancer cells, SKOV3ip1 and IGROV1, growing orthotopically in nude mice. Mice with established disease were treated with vehicle (control), paclitaxel (weekly, intraperitoneal injections), macitentan (daily oral administrations), or a combination of paclitaxel and macitentan. Treatment with paclitaxel decreased tumor weight and volume of ascites. Combination therapy with macitentan and paclitaxel reduced tumor incidence and further reduced tumor weight and volume of ascites when compared with paclitaxel alone. Macitentan alone occasionally reduced tumor weight but alone had no effect on tumor incidence or ascites. Immunohistochemical analyses revealed that treatment with macitentan and macitentan plus paclitaxel inhibited the phosphorylation of ETRs and suppressed the survival pathways of tumor cells by decreasing the levels of pVEGFR2, pAkt, and pMAPK. The dose of macitentan necessary for inhibition of phosphorylation correlated with the dose required to increase antitumor efficacy of paclitaxel. Treatment with macitentan enhanced the cytotoxicity mediated by paclitaxel as measured by the degree of apoptosis in tumor cells and tumor-associated endothelial cells. Collectively, these results show that administration of macitentan in combination with paclitaxel prevents the progression of ovarian cancer in the peritoneal cavity of nude mice in part by inhibiting survival pathways of both tumor cells and tumor-associated endothelial cells. PMID:21403842

  18. Nab-paclitaxel-associated photosensitivity: report in a woman with non-small cell lung cancer and review of taxane-related photodermatoses

    PubMed Central

    Beutler, Bryce D.; Cohen, Philip R.

    2015-01-01

    Background: Taxanes [paclitaxel, nab-paclitaxel (Abraxane, Celgene Corp, USA), and docetaxel]—used in the treatment of lung, breast, and head and neck cancers—have been associated with cutaneous adverse effects, including photodermatoses. Purpose: We describe a woman with non-small cell lung cancer who developed a photodistributed dermatitis associated with her nab-paclitaxel therapy and review photodermatoses in patients receiving taxanes. Materials and methods: The features of a woman with a nab-paclitaxel-associated photodistributed dermatitis are presented and the literature on nab-paclitaxel-associated photosensitivity is reviewed. Results: Our patient developed nab-paclitaxel-associated photodistributed dermatitis on the sun-exposed surfaces of her upper extremities, which was exacerbated with each course of nab-paclitaxel. Biopsies revealed an interface dermatitis and laboratory studies were negative for lupus erythematosus and dermatomyositis. Her condition improved following topical corticosteroid cream application and strict avoidance of sunlight. Conclusion: Chemotherapy can be associated with adverse mucocutaneous events, including dermatoses on sun-exposed areas of the skin. Paclitaxel and nab-paclitaxel have both been associated with photodermatoses, including dermatitis, erythema multiforme, onycholysis, and subacute cutaneous lupus erythematosus. Strict avoidance of sun exposure, topical or oral corticosteroids, and/or discontinuation of the drug results in improvement with progressive resolution of symptoms and skin lesions. Development of photodermatoses is not an absolute contraindication to continuing chemotherapy, provided that the cutaneous condition resolves with dermatosis-directed treatment and the patient avoids sun exposure. PMID:26114068

  19. Combinatorial TGF-β attenuation with paclitaxel inhibits the epithelial-to-mesenchymal transition and breast cancer stem-like cells.

    PubMed

    Park, So-Yeon; Kim, Min-Jin; Park, Sang-A; Kim, Jung-Shin; Min, Kyung-Nan; Kim, Dae-Kee; Lim, Woosung; Nam, Jeong-Seok; Sheen, Yhun Yhong

    2015-11-10

    Distant relapse after chemotherapy is an important clinical issue for treating breast cancer patients and results from the development of cancer stem-like cells (CSCs) during chemotherapy. Here we report that blocking epithelial-to-mesenchymal transition (EMT) suppresses paclitaxel-induced CSCs properties by using a MDA-MB-231-xenografted mice model (in vivo), and breast cancer cell lines (in vitro). Paclitaxel, one of the cytotoxic taxane-drugs such as docetaxel, increases mesenchymal markers (Vimentin and Fibronectin) and decreases an epithelial marker (Zo-1). Blocking TGF-β signaling with the TGF-β type I receptor kinase (ALK5) inhibitor, EW-7197, suppresses paclitaxel-induced EMT and CSC properties such as mammosphere-forming efficiency (MSFE), aldehyde dehydrogenase (ALDH) activity, CD44+/CD24- ratio, and pluripotency regulators (Oct4, Nanog, Klf4, Myc, and Sox2). The combinatorial treatment of EW-7197 improves the therapeutic effect of paclitaxel by decreasing the lung metastasis and increasing the survival time in vivo. We confirmed that Snail is increased by paclitaxel-induced intracellular reactive oxygen species (ROS) and EW-7197 suppresses the paclitaxel-induced Snail and EMT by attenuating paclitaxel-induced intracellular ROS. Knock-down of SNAI1 suppresses paclitaxel-induced EMT and CSC properties. These data together suggest that blocking the Snail-induced EMT with the ALK5 inhibitor attenuates metastasis after paclitaxel-therapy and that this combinatorial approach could prove useful in treating breast cancer. PMID:26462028

  20. 212Pb-radioimmunotherapy potentiates paclitaxel-induced cell killing efficacy by perturbing the mitotic spindle checkpoint

    PubMed Central

    Yong, K J; Milenic, D E; Baidoo, K E; Brechbiel, M W

    2013-01-01

    Background: Paclitaxel has recently been reported by this laboratory to potentiate the high-LET radiation therapeutic 212Pb-TCMC-trastuzumab, which targets HER2. To elucidate mechanisms associated with this therapy, targeted α-particle radiation therapeutic 212Pb-TCMC-trastuzumab together with paclitaxel was investigated for the treatment of disseminated peritoneal cancers. Methods: Mice bearing human colon cancer LS-174T intraperitoneal xenografts were pre-treated with paclitaxel, followed by treatment with 212Pb-TCMC-trastuzumab and compared with groups treated with paclitaxel alone, 212Pb-TCMC-HuIgG, 212Pb-TCMC-trastuzumab and 212Pb-TCMC-HuIgG after paclitaxel pre-treatment. Results: 212Pb-TCMC-trastuzumab with paclitaxel given 24 h earlier induced increased mitotic catastrophe and apoptosis. The combined modality of paclitaxel and 212Pb-TCMC-trastuzumab markedly reduced DNA content in the S-phase of the cell cycle with a concomitant increase observed in the G2/M-phase. This treatment regimen also diminished phosphorylation of histone H3, accompanied by an increase in multi-micronuclei, or mitotic catastrophe in nuclear profiles and positively stained γH2AX foci. The data suggests, possible effects on the mitotic spindle checkpoint by the paclitaxel and 212Pb-TCMC-trastuzumab treatment. Consistent with this hypothesis, 212Pb-TCMC-trastuzumab treatment in response to paclitaxel reduced expression and phosphorylation of BubR1, which is likely attributable to disruption of a functional Aurora B, leading to impairment of the mitotic spindle checkpoint. In addition, the reduction of BubR1 expression may be mediated by the association of a repressive transcription factor, E2F4, on the promoter region of BubR1 gene. Conclusion: These findings suggest that the sensitisation to therapy of 212Pb-TCMC-trastuzumab by paclitaxel may be associated with perturbation of the mitotic spindle checkpoint, leading to increased mitotic catastrophe and cell death. PMID:23632482

  1. A comparison of carboplatin and paclitaxel with cisplatinum and 5-fluorouracil in definitive chemoradiation in esophageal cancer patients

    PubMed Central

    Honing, J.; Smit, J. K.; Muijs, C. T.; Burgerhof, J. G. M.; de Groot, J. W.; Paardekooper, G.; Muller, K.; Woutersen, D.; Legdeur, M. J. C.; Fiets, W. E.; Slot, A.; Beukema, J. C.; Plukker, J. Th. M.; Hospers, G. A. P.

    2014-01-01

    Background In esophageal cancer (EC) patients who are not eligible for surgery, definitive chemoradiation (dCRT) with curative intent using cisplatinum with 5-fluorouracil (5-FU) is the standard chemotherapy regimen. Nowadays carboplatin/paclitaxel is also often used. In this study, we compared survival and toxicity rates between both regimens. Patients and methods This multicenter study included 102 patients treated in five centers in the Northeast Netherlands from 1996 till 2008. Forty-seven patients received cisplatinum/5-FU (75 mg/m2 and 1 g/m2) and 55 patients carboplatin/paclitaxel (AUC2 and 50 mg/m2). Results Overall survival (OS) was not different between the cisplatinum/5-FU and carboplatin/paclitaxel group {[P = 0.879, hazard ratio (HR) 0.97 [confidence interval (CI) 0.62–1.51]}, with a median survival of 16.1 (CI 11.8–20.5) and 13.8 months (CI 10.8–16.9). Median disease-free survival (DFS) was comparable [P = 0.760, HR 0.93 (CI 0.60–1.45)] between the cisplatinum/5-FU group [11.1 months (CI 6.9–15.3)] and the carboplatin/paclitaxel group [9.7 months (CI 5.1–14.4)]. Groups were comparable except clinical T stage was higher in the carboplatin/paclitaxel group (P = 0.008). High clinical T stage (cT4) was not related to OS and DFS in a univariate analysis (P = 0.250 and P = 0.201). A higher percentage of patients completed the carboplatin/paclitaxel regimen (82% versus 57%, P = 0.010). Hematological and nonhematological toxicity (≥grade 3) in the carboplatin/paclitaxel group (4% and 18%) was significantly lower than in the cisplatinum/5-FU (19% and 38%, P = 0.001). Conclusions In this study, we showed comparable outcome, in terms of DFS and OS for carboplatin/paclitaxel compared with cisplatinum/5-FU as dCRT treatment in EC patients. Toxicity rates were lower in the carboplatin/paclitaxel group together with higher treatment compliance. Carboplatin/paclitaxel as an alternative treatment of cisplatinum/5-FU is a good candidate regimen for further evaluation. PMID:24492674

  2. Complete response to second line Paclitaxel every 2 weeks of eyelid kaposi sarcoma: a case report.

    PubMed

    Brunetti, Anna Elisabetta; Guarini, Attilio; Lorusso, Vito; Minoia, Carla; Sabatelli, Angela; Marech, Ilaria; Silvestris, Nicola

    2013-01-01

    A 77-year-old male patient presented to our attention with violaceous nodular lesions on the skin of his hands and lower extremities. Clinical and histologic examination supported the diagnosis of Kaposi sarcoma. A first-line systemic chemotherapy based on liposomal doxorubicin at a dosage of 40 mg/m2 every 3 weeks for 5 cycles was carried out, resulting in partial resolution of skin lesions. However, 1 year later, a relapse of the disease in the lower limbs and a new lesion of the left eyelid were found, therefore the patient began a second-line therapy with 100 mg/m2 paclitaxel every 2 weeks. After 8 cycles of therapy, we observed a complete remission of eyelid tumor and a partial response of lower limbs lesions up to 6 months of follow up. In conclusion, eyelid Kaposi sarcoma was successfully treated with paclitaxel every 2 weeks, obtaining a complete response. PMID:23247036

  3. Phase behavior study of paclitaxel loaded amphiphilic copolymer in two solvents by dissipative particle dynamics simulations

    NASA Astrophysics Data System (ADS)

    Guo, Xin Dong; Tan, Jeremy Pang Kern; Zhang, Li Juan; Khan, Majad; Liu, Shao Qiong; Yang, Yi Yan; Qian, Yu

    2009-05-01

    DPD simulations were employed to study the phase behavior of paclitaxel loaded PEO 11- b-PLLA 9 in water and N, N-Dimethylformamide. Different ordered structures were observed in water-rich solvents. All the structures were greatly affected by solvents compositions. By varying the fractions of each component, a phase diagram of paclitaxel loaded PEO 11- b-PLLA 9 in water and DMF was mapped. For all ordered structures, bicontinuous, lamella, rod, and spherical structures with different sizes could be easily observed for their wide distribution in the phase diagram. While the HPL, dumbbell, and spherical structures with uniform size were difficult to be obtained, due to their narrow distribution.

  4. Paclitaxel- and/or cisplatin-induced ocular neurotoxicity: a case report and literature review

    PubMed Central

    Li, Ying; Li, Yanping; Li, Junyu; Pi, Guoliang; Tan, Wenyong

    2014-01-01

    Paclitaxel (PTX) and/or cisplatin (CDDP), as important cytotoxic anti-cancer agents, are widely used to treat various solid tumors. Both may cause moderate or severe neurotoxicity, but ocular neurotoxicity is also occasionally reported. A patient diagnosed with nasopharyngeal cancer suffering acute ocular neurotoxicity 10 days after paclitaxel and CDDP administration at the recommended dose is described in the present case report, and PTX- and/or CDDP-induced ocular neurotoxicity are summarized according to previous reports. Possible mechanisms and the potential diagnostic, therapeutic and predictive strategies of PTX- and/or CDDP-induced ocular neurotoxicity are reviewed, to help the oncologist to take the infrequent toxicity of cytotoxic drugs into account and improve patient safety during anti-cancer therapy. PMID:25114574

  5. Confocal Raman data analysis enables identifying apoptosis of MCF-7 cells caused by anticancer drug paclitaxel

    NASA Astrophysics Data System (ADS)

    Salehi, Hamideh; Middendorp, Elodie; Panayotov, Ivan; Dutilleul, Pierre-Yves Collard; Vegh, Attila-Gergely; Ramakrishnan, Sathish; Gergely, Csilla; Cuisinier, Frederic

    2013-05-01

    Confocal Raman microscopy is a noninvasive, label-free imaging technique used to study apoptosis of live MCF-7 cells. The images are based on Raman spectra of cells components, and their apoptosis is monitored through diffusion of cytochrome c in cytoplasm. K-mean clustering is used to identify mitochondria in cells, and correlation analysis provides the cytochrome c distribution inside the cells. Our results demonstrate that incubation of cells for 3 h with 10 μM of paclitaxel does not induce apoptosis in MCF-7 cells. On the contrary, incubation for 30 min at a higher concentration (100 μM) of paclitaxel induces gradual release of the cytochrome c into the cytoplasm, indicating cell apoptosis via a caspase independent pathway.

  6. Effect of the paclitaxel vehicle, Cremophor EL, on the pharmacokinetics of doxorubicin and doxorubicinol in mice.

    PubMed Central

    Webster, L. K.; Cosson, E. J.; Stokes, K. H.; Millward, M. J.

    1996-01-01

    The effect of the paclitaxel vehicle Cremophor on the pharmacokinetics of doxorubicin and doxorubicinol was studied in two groups of mice given intravenously either 2.5 ml kg-1 Cremophor or saline followed 5 min later by 10 mg kg-1 doxorubicin. In each group three mice were sacrificed at ten time points and doxorubicin and doxorubicinol were measured in plasma by high-performance liquid chromatography (HPLC). With Cremophor present, doxorubicin AUC increased from 1420+/-440 to 2770+/-660 ng h ml(-1) (P<0.05) and doxorubicinol AUC increased from 130+/-76 to 320+/-88 ng h ml(-1) (p<0.05). Neither the terminal elimination half-lives nor the doxorubicinol-doxorubicin AUC ratio changed in the presence of Cremophor, suggesting a lack of a direct effect on drug metabolism. The possibility exists the Cremophor may change the pharmacokinetics of both paclitaxel and other drugs given concurrently. PMID:8595168

  7. Nab-paclitaxel for the management of triple-negative metastatic breast cancer: a case study

    PubMed Central

    De Placido, Sabino; De Angelis, Carmine

    2015-01-01

    The optimal sequence of systemic chemotherapy in metastatic breast cancer (MBC) is unknown. We report the case of a woman who was successfully treated with nanoparticle albumin-bound (nab)-paclitaxel for triple negative MBC in our institution. In November 2008, a 48-year-old woman underwent surgical treatment for a triple negative invasive ductal breast cancer and subsequently received adjuvant chemotherapy with fluorouracil/epirubicin/cyclophosphamide and radiotherapy. Sixteen months after surgery, she presented with a left chest wall metastatasis. The patient received combination therapy with conventional paclitaxel (90mg/m weekly for 3 out of 4 weeks [QW 3/4]) and bevacizumab (10mg/kg every 2 weeks [Q2W]) as first-line treatment for MBC (six cycles; March to September 2010) and achieved a partial response at the metastatic site. Bevacizumab monotherapy was continued until disease progression (April 2011) with the development of a single infraclavicular lymph node metastasis and an increase in the dimensions of the left chest wall lesion. From May to December 2011, the patient received nab-paclitaxel 260mg/m every 3 weeks (Q3W) as second-line treatment (11 cycles). After three cycles, the left chest wall lesion and the infraclavicular lymph node metastasis were undetectable and the patient was considered to have achieved a complete response. Treatment was well tolerated with no significant toxicity or need for dose reduction. Given our case, here we review the clinical evidence and discuss the potential role of nab-paclitaxel for the treatment of triple negative MBC, a subgroup typically characterized as having aggressive disease and limited treatment options. PMID:25115342

  8. Targeted Delivery of Paclitaxel to EphA2-Expressing Cancer Cells

    PubMed Central

    Wang, Si; Noberini, Roberta; Stebbins, John L.; Das, Swadesh; Zhang, Ziming; Wu, Bainan; Mitra, Sayantan; Billet, Sandrine; Fernandez, Ana; Bhowmick, Neil A.; Kitada, Shinichi; Pasquale, Elena B.; Fisher, Paul B.; Pellecchia, Maurizio

    2012-01-01

    Purpose YSA is an EphA2-targeting peptide that effectively delivers anti-cancer agents to prostate cancer tumors (1). Here, we report on how we increased the drug-like properties of this delivery system. Experimental Design By introducing non-natural amino acids, we have designed two new EphA2 targeting peptides: YNH, where norleucine and homoserine replace the two methionine residues of YSA, and dYNH, where a D-tyrosine replaces the L-tyrosine at the first position of the YNH peptide. We describe the details of the synthesis of YNH and dYNH paclitaxel conjugates (YNH-PTX and dYNH-PTX) and their characterization in cells and in vivo. Results dYNH-PTX showed improved stability in mouse serum and significantly reduced tumor size in a prostate cancer xenograft model and also reduced tumor vasculature in a syngeneic orthotopic allograft mouse model of renal cancer compared to vehicle or paclitaxel treatments. Conclusion This study reveals that targeting EphA2 with dYNH drug conjugates could represent an effective way to deliver anti-cancer agents to a variety of tumor types. Translational Relevance Overexpression of the EphA2 positively correlates with tumor malignancy and poor prognosis. For this reason, EphA2 is an attractive target for cancer cell specific drug delivery. In this study, we report on the development of dYNH, an EphA2 targeting peptide that when coupled to paclitaxel (PTX) has favorable pharmacological properties and possesses powerful anti-tumor activity in vivo. dYNH-PTX may allow for an expanded therapeutic index of paclitaxel as well as precluding the need for complex formulations and long infusion times. PMID:23155185

  9. Paclitaxel and Its Evolving Role in the Management of Ovarian Cancer.

    PubMed

    Kampan, Nirmala Chandralega; Madondo, Mutsa Tatenda; McNally, Orla M; Quinn, Michael; Plebanski, Magdalena

    2015-01-01

    Paclitaxel, a class of taxane with microtubule stabilising ability, has remained with platinum based therapy, the standard care for primary ovarian cancer management. A deeper understanding of the immunological basis and other potential mechanisms of action together with new dosing schedules and/or routes of administration may potentiate its clinical benefit. Newer forms of taxanes, with better safety profiles and higher intratumoural cytotoxicity, have yet to demonstrate clinical superiority over the parent compound. PMID:26137480

  10. Paclitaxel and Its Evolving Role in the Management of Ovarian Cancer

    PubMed Central

    Kampan, Nirmala Chandralega; Madondo, Mutsa Tatenda; McNally, Orla M.; Quinn, Michael; Plebanski, Magdalena

    2015-01-01

    Paclitaxel, a class of taxane with microtubule stabilising ability, has remained with platinum based therapy, the standard care for primary ovarian cancer management. A deeper understanding of the immunological basis and other potential mechanisms of action together with new dosing schedules and/or routes of administration may potentiate its clinical benefit. Newer forms of taxanes, with better safety profiles and higher intratumoural cytotoxicity, have yet to demonstrate clinical superiority over the parent compound. PMID:26137480

  11. The role of Six1 signaling in paclitaxel-dependent apoptosis in MCF-7 cell line

    PubMed Central

    Armat, Marzieh; Bakhshaiesh, Taiebeh Oghabi; Sabzichi, Mehdi; Shanehbandi, Dariush; Sharifi, Simin; Molavi, Ommoleila; Mohammadian, Jamal; Hejazi, Mohammad Saeid; Samadi, Nasser

    2016-01-01

    The resistance of cancer cells to chemotherapeutic agents represents the main problem in cancer treatment. Despite intensive research, mechanisms of resistance have not yet been fully elucidated. Six1 signaling has an important role in the expansion of progenitor cell populations during early embryogenesis. Six1 gene overexpression has been strongly associated with aggressiveness, invasiveness, and poor prognosis of different cancers. In this study, we investigated the role of Six1 signaling in resistance of MCF-7 breast cancer cells to taxanes. We first established in vitro paclitaxel-resistant MCF-7 breast cancer cells. Morphological modifications in paclitaxel-resistant cells were examined via light microscopic images and fluorescence-activated cell sorting analysis. Applying quantitative real-time polymerase chain reaction, we measured Six1, B-cell lymphoma/leukemia(BCL-2), BAX, and P53 mRNA expression levels in both non-resistant and resistant cells. Resistant cells were developed from the parent MCF-7 cells by applying increasing concentrations of paclitaxel up to 64 nM. The inhibitory concentration 50% value in resistant cells increased from 3.5 ± 0.03 to 511 ± 10.22 nM (p = 0.015). In paclitaxel-resistant cells, there was a significant increase in Six1 and BCL-2 mRNA levels (p = 0.0007) with a marked decrease in pro-apoptotic Bax mRNA expression level (p = 0.03); however, there was no significant change in P53 expression (p = 0.025). Our results suggest that identifying cancer patients with high Six1 expression and then inhibition of Six1 signaling can improve the efficiency of chemotherapeutic agents in the induction of apoptosis. PMID:26773176

  12. B7-H3 silencing increases paclitaxel sensitivity by abrogating Jak2/Stat3 phosphorylation

    PubMed Central

    Liu, Hao; Tekle, Christina; Chen, Yih-Wen; Kristian, Alexandr; Zhao, Yuhua; Zhou, Ming; Liu, Zixing; Ding, Yan; Wang, Bin; Mlandsmo, Gunhild Mari; Nesland, Jahn Marthin; Fodstad, Oystein; Tan, Ming

    2012-01-01

    In many types of cancer, the expression of the immunoregulatory protein B7-H3 has been associated with poor prognosis. Previously, we observed a link between B7-H3 and tumor cell migration and invasion, and in present work we have investigated the role of B7-H3 in chemoresistance in breast cancer. We observed that silencing of B7-H3, via stable shRNA or transient siRNA transfection, increased the sensitivity of multiple human breast cancer cell lines to paclitaxel as a result of enhanced drug-induced apoptosis. Overexpression of B7-H3 made the cancer cells more resistant to the drug. Next, we investigated the mechanisms behind B7-H3 mediated paclitaxel resistance, and found that the level of Stat3 Tyr705 phosphorylation was decreased in B7-H3 knockdown cells, along with the expression of its direct downstream targets Mcl-1 and Survivin. The phosphorylation of Jak2, an upstream molecule of Stat3, was also significantly decreased. In contrast, reexpression of B7-H3 in B7-H3 knockdown and low B7-H3- expressing cells increased the phosphorylation of Jak2 and Stat3. In vivo animal experiments showed that B7-H3 knock down tumors displayed a slower growth rate than the control xenografts. Importantly, paclitaxel treatment showed a strong anti-tumor activity in the mice with B7-H3 knockdown tumors, but only a marginal effect in the control group. Taken together, our data demonstrate that in breast cancer cells B7-H3 induces paclitaxel resistance, at least partially by interfering with Jak2/Stat3 pathway. These results provide novel insight into the function of B7-H3 and encourage the design and testing of approaches targeting this protein and its partners. PMID:21518725

  13. Microtubule-Binding Proteins as Promising Biomarkers of Paclitaxel Sensitivity in Cancer Chemotherapy

    PubMed Central

    Xie, Songbo; Ogden, Angela; Aneja, Ritu; Zhou, Jun

    2016-01-01

    Microtubules, tirelessly animated and highly dynamic structures, are vital for most cellular processes and their intricacies are still being revealed even after a century since their discovery. The importance of microtubules as chemotherapeutic targets cannot be overstated, and their clinical role is unlikely to abate in the near future. Indeed, improved understanding of microtubule biology could herald a new epoch of anticancer drug design by permitting fine-tuning of microtubule-targeting agents, the clinical utility of which is presently often limited by primary or acquired resistance. Paclitaxel, one such agent belonging to the taxane family, has proven a resoundingly successful treatment for many cancer patients; however, for too many others with paclitaxel-refractory tumors, the drug has offered nothing but side effects. Accumulating evidence suggests that microtubule-binding proteins (MBPs) can regulate paclitaxel sensitivity in a wide range of cancer types. Improved understanding of how these proteins can be assayed to predict treatment responses or manipulated pharmacologically to improve clinical outcomes could transform modern chemotherapy and is urgently awaited. PMID:26332739

  14. Paclitaxel-induced lung injury and its amelioration by parecoxib sodium

    PubMed Central

    Liu, Wen-jie; Zhong, Zhong-jian; Cao, Long-hui; Li, Hui-ting; Zhang, Tian-hua; Lin, Wen-qian

    2015-01-01

    To investigate the mechanism of paclitaxel-induced lung injury and its amelioration by parecoxib sodium. In this study, rats were randomly divided into: the control group (Con); the paclitaxel chemotherapy group (Pac); the paclitaxel+ parecoxib sodium intervention group (Pac?+?Pare); and the parecoxib sodium group (Pare). We observed changes in alveolar ventilation function, alveolar-capillary membrane permeability, lung tissue pathology and measured the levels of inflammatory cytokines and cyclooxygenase-2 (Cox-2) in lung tissue, the expression of tight junction proteins (Zo-1 and Claudin-4). Compared with the Con group, the lung tissue of the Pac group showed significantly increased expression of Cox-2 protein (p?

  15. [Two advanced gastric cancer cases with peritoneal metastases successfully treated by s-1/paclitaxel combination therapy].

    PubMed

    Ina, Kenji; Furuta, Ryuichi; Kataoka, Takae; Nishio, Tomoko; Nagao, Seiji; Kayukawa, Satoshi; Masaki, Ayako; Ando, Takafumi; Goto, Hidemi

    2009-06-01

    Two unresectable advanced gastric cancer cases with peritoneal metastases were successfully treated by the combination therapy of S-1 and paclitaxel. S-1 (1.25m(2): 80 mg/day, 1.25m(2)-1.50m(2)<:120 mg/day) was administered orally for 14 consecutive days followed by 14 days rest and a 2-hour infusion of paclitaxel (50 mg/m(2)) was administered on day 1 and 15 of each course. Treatment was repeated every 4 weeks unless disease progression or severe adverse effects were observed. Case 1: 65-year-old male (performance status: PS 3) with type 1 gastric cancer with malignant ascites. Case 2: 66-year-old male (PS3) with peritoneal metastases whose primary gastric lesion was surgically resected. Partial response was obtained in the former and complete response in the latter. Combination therapy of S-1 and paclitaxel can be highly recommended for patients with inoperable gastric cancer with poor PS. PMID:19542719

  16. A phase I study of dasatinib and weekly paclitaxel for metastatic breast cancer

    PubMed Central

    Fornier, M. N.; Morris, P. G.; Abbruzzi, A.; D'Andrea, G.; Gilewski, T.; Bromberg, J.; Dang, C.; Dickler, M.; Modi, S.; Seidman, A. D.; Sklarin, N.; Chang, J.; Norton, L.; Hudis, C. A.

    2011-01-01

    Background: SRC plays an important role in the pathogenesis of metastatic breast cancer (MBC). In preclinical models, paclitaxel and the oral SRC inhibitor dasatinib showed greater antitumor activity than either agent. To determine the maximum tolerated dose of this combination, we conducted a phase I study. Patients and methods: Patients with MBC; Eastern Cooperative Oncology Group performance status of zero to one; normal hepatic, renal and marrow function were eligible. Paclitaxel 80 mg/m2 was given 3 weeks of 4. The starting dasatinib dose was 70 mg and was increased, using a standard 3?+?3 dose-escalation scheme. Results: Fifteen patients enrolled (median age 54 years, range 3574). No dose-limiting toxic effects (DLTs) occurred at dasatinib doses of 70120 mg. One DLT (grade 3 fatigue) occurred in the dasatinib 150-mg cohort, which was expanded (six patients) with no further DLTs. However, due to cumulative toxic effects (rash, fatigue, diarrhea), the recommended phase II dose is dasatinib 120 mg. Of 13 assessable patients, a partial response was seen in 4 patients (31%), including 2 patients previously treated with taxanes; all received ?120 mg dasatinib. An additional five patients (29%) had stable disease. Conclusion: In combination with weekly paclitaxel, the recommended phase II dose of dasatinib is 120 mg daily and preliminary activity has been seen in patients with MBC. PMID:21406471

  17. Efficacy and safety of nab-paclitaxel combined with carboplatin in Chinese patients with melanoma.

    PubMed

    Guo, Yi-qun; Ding, Ya; Li, Dan-dan; Li, Jing-jing; Peng, Rui-qing; Wen, Xi-zhi; Zhang, Xing; Zhang, Xiao-Shi

    2015-09-01

    This study aimed to evaluate the efficacy and safety of nab-paclitaxel combined with carboplatin in Chinese patients with melanoma. The treatment regimen consisted of nab-paclitaxel (100 mg/m(2)) and carboplatin (area under the curve = 2) administered on days 1 and 8 every 21 days. All of the patients were evaluated on the basis of efficacy and safety in a two-cycle interval. Of the 45 patients, 18 were chemotherapy naive and 27 were chemotherapy treated. Of these cases, 18 manifested acral melanoma and 27 showed non-acral melanomas. Although chemotherapy-naive patients exhibited a higher response to the treatment, similar progression-free survival (PFS) and overall survival (OS) were detected in chemotherapy-naive and chemotherapy-treated patients. A higher response was observed in non-acral melanomas; however, similar PFS and OS occurred between acral and non-acral melanomas. The most common side effects were alopecia, myelosuppression, and gastrointestinal reaction. Nab-paclitaxel combined with carboplatin is a well-tolerated and effective regimen to treat Chinese patients with melanoma, including acral and non-acral melanomas. This treatment may be an alternative approach for Chinese patients with melanoma, especially those without the opportunity to undergo therapy with immune checkpoint inhibitors. PMID:26298530

  18. c(RGDyK)-decorated Pluronic micelles for enhanced doxorubicin and paclitaxel delivery to brain glioma.

    PubMed

    Huang, YuKun; Liu, Wenchao; Gao, Feng; Fang, Xiaoling; Chen, Yanzuo

    2016-01-01

    Brain glioma therapy is an important challenge in oncology. Here, doxorubicin (DOX) and paclitaxel (PTX)-loaded cyclic arginine-glycine-aspartic acid peptide (c(RGDyK))-decorated Pluronic micelles (cyclic arginine-glycine-aspartic acid peptide-decorated Pluronic micelles loaded with doxorubicin and paclitaxel [RGD-PF-DP]) were designed as a potential targeted delivery system to enhance blood-brain barrier penetration and improve drug accumulation via integrin-mediated transcytosis/endocytosis and based on integrin overexpression in blood-brain barrier and glioma cells. The physicochemical characterization of RGD-PF-DP revealed a satisfactory size of 28.5±0.12 nm with uniform distribution and core-shell structure. The transport rates across the in vitro blood-brain barrier model, cellular uptake, cytotoxicity, and apoptosis of U87 malignant glioblastoma cells of RGD-PF-DP were significantly greater than those of non-c(RGDyK)-decorated Pluronic micelles. In vivo fluorescence imaging demonstrated the specificity and efficacy of intracranial tumor accumulation of RGD-PF-DP. RGD-PF-DP displayed an extended median survival time of 39 days, with no serious body weight loss during the regimen. No acute toxicity to major organs was observed in mice receiving treatment doses via intravenous administration. In conclusion, RGD-PF-DP could be a promising vehicle for enhanced doxorubicin and paclitaxel delivery in patients with brain glioma. PMID:27143884

  19. Chemosensitizing activities of cyclotides from Clitoria ternatea in paclitaxel-resistant lung cancer cells

    PubMed Central

    SEN, ZHANG; ZHAN, XIAO KAI; JING, JIN; YI, ZHANG; WANQI, ZHOU

    2013-01-01

    Cyclotides comprise a family of circular mini-peptides that have been isolated from various plants and have a wide range of bioactivities. Previous studies have demonstrated that cyclotides have antitumor effects and cause cell death by membrane permeabilization. The present study aimed to evaluate the cytotoxicity and chemosensitizing activities of cyclotides from Clitoria ternatea in paclitaxel-resistant lung cancer cells. In this study, a total of seven cyclotides were selected for colorimetric cell viability assay (MTT assay) to evaluate their anticancer and chemosensitizing activities in the lung cancer cell line A549 and its sub-line A549/paclitaxel. Results suggested that certain cyclotides had significant anticancer and chemosensitizing abilities; such cyclotides were capable of causing multi-fold decreases in the half maximal inhibitory concentration (IC50) value of cliotides in the presence of paclitaxel. More importantly, their bioactivities were found to be correlated with their net charge status. In conclusion, cyclotides from C. ternatea have potential in chemosensitization application. PMID:23419988

  20. Combination of Rotational Atherothrombectomy and Paclitaxel-Coated Angioplasty for Femoropopliteal Occlusion

    PubMed Central

    Scheer, F; Lüdtke, CW; Kamusella, P; Wiggermann, P; Vieweg, H; Schlöricke, E; Lichtenberg, M; Andresen, R; Wissgott, C

    2014-01-01

    OBJECTIVE The rotational atherothrombectomy with Straub Rotarex® is a safe and efficient treatment of acute/subactute vascular occlusions. The purpose of this study was to evaluate the benefit of paclitaxel-coated angioplasty after rotational atherothrombectomy over an observation period of six months. MATERIALS AND METHODS Overall, 29 patients were treated with the Rotarex catheter in combination with paclitaxel-coated angioplasty. All patients had acute/subacute and chronic occlusions of the superficial femoral artery (SFA) and/or popliteal arteries. The ankle-brachial index (ABI) was detected before the intervention, after the procedure, and after six months. Also clinical examination and ultrasound scans were done in the observation period. RESULTS There were no technical failures. The ABI shows a significant increase from 0.52 ± 0.17 to 0.91 ± 0.25 in the follow-up. By ultrasound examination, there were found two (6.9%) restenoses during the follow-up. There was one dissection during the intervention (3.5%). CONCLUSION The rotational atherothrombectomy in combination with paclitaxel-coated angioplasty might be an effective and safe method with a promising low rate of restenosis at six months. PMID:25983558

  1. c(RGDyK)-decorated Pluronic micelles for enhanced doxorubicin and paclitaxel delivery to brain glioma

    PubMed Central

    Huang, YuKun; Liu, Wenchao; Gao, Feng; Fang, Xiaoling; Chen, Yanzuo

    2016-01-01

    Brain glioma therapy is an important challenge in oncology. Here, doxorubicin (DOX) and paclitaxel (PTX)-loaded cyclic arginine-glycine-aspartic acid peptide (c(RGDyK))-decorated Pluronic micelles (cyclic arginine-glycine-aspartic acid peptide-decorated Pluronic micelles loaded with doxorubicin and paclitaxel [RGD-PF-DP]) were designed as a potential targeted delivery system to enhance blood–brain barrier penetration and improve drug accumulation via integrin-mediated transcytosis/endocytosis and based on integrin overexpression in blood–brain barrier and glioma cells. The physicochemical characterization of RGD-PF-DP revealed a satisfactory size of 28.5±0.12 nm with uniform distribution and core-shell structure. The transport rates across the in vitro blood–brain barrier model, cellular uptake, cytotoxicity, and apoptosis of U87 malignant glioblastoma cells of RGD-PF-DP were significantly greater than those of non-c(RGDyK)-decorated Pluronic micelles. In vivo fluorescence imaging demonstrated the specificity and efficacy of intracranial tumor accumulation of RGD-PF-DP. RGD-PF-DP displayed an extended median survival time of 39 days, with no serious body weight loss during the regimen. No acute toxicity to major organs was observed in mice receiving treatment doses via intravenous administration. In conclusion, RGD-PF-DP could be a promising vehicle for enhanced doxorubicin and paclitaxel delivery in patients with brain glioma. PMID:27143884

  2. Microtubule-Binding Proteins as Promising Biomarkers of Paclitaxel Sensitivity in Cancer Chemotherapy.

    PubMed

    Xie, Songbo; Ogden, Angela; Aneja, Ritu; Zhou, Jun

    2016-03-01

    Microtubules, tirelessly animated and highly dynamic structures, are vital for most cellular processes and their intricacies are still being revealed even after a century since their discovery. The importance of microtubules as chemotherapeutic targets cannot be overstated, and their clinical role is unlikely to abate in the near future. Indeed, improved understanding of microtubule biology could herald a new epoch of anticancer drug design by permitting fine-tuning of microtubule-targeting agents, the clinical utility of which is presently often limited by primary or acquired resistance. Paclitaxel, one such agent belonging to the taxane family, has proven a resoundingly successful treatment for many cancer patients; however, for too many others with paclitaxel-refractory tumors, the drug has offered nothing but side effects. Accumulating evidence suggests that microtubule-binding proteins (MBPs) can regulate paclitaxel sensitivity in a wide range of cancer types. Improved understanding of how these proteins can be assayed to predict treatment responses or manipulated pharmacologically to improve clinical outcomes could transform modern chemotherapy and is urgently awaited. PMID:26332739

  3. Confirmed Activity and Tolerability of Weekly Paclitaxel in the Treatment of Advanced Angiosarcoma

    PubMed Central

    Apice, Gaetano; Pizzolorusso, Antonio; Di Maio, Massimo; Grignani, Giovanni; Gebbia, Vittorio; Buonadonna, Angela; De Chiara, Annarosaria; Fazioli, Flavio; De Palma, Giampaolo; Galizia, Danilo; Arcara, Carlo; Mozzillo, Nicola; Perrone, Francesco

    2016-01-01

    Background. In several prospective and retrospective studies, weekly paclitaxel showed promising activity in patients with angiosarcoma. Patients and Methods. Our study was originally designed as a prospective, phase II multicenter trial for patients younger than 75, with ECOG performance status 0–2, affected by locally advanced or metastatic angiosarcoma. Patients received paclitaxel 80 mg/m2 intravenously, at days 1, 8, and 15 every 4 weeks, until disease progression or unacceptable toxicity. Primary endpoint was objective response. Results. Eight patients were enrolled but, due to very slow accrual, the trial was prematurely stopped and further 10 patients were retrospectively included in the analysis. Out of 17 evaluable patients, 6 patients obtained an objective response (5 partial, 1 complete), with an objective response rate of 35% (95% confidence interval 17%–59%). Of note, five responses were obtained in pretreated patients. In the paper, details of overall survival, progression-free survival, and tolerability are reported. Conclusions. In this small series of patients with locally advanced or metastatic angiosarcoma, weekly paclitaxel was confirmed to be well tolerated and active even in pretreated patients. PMID:27019606

  4. Bioresorbable copolymer of L-lactide and ε-caprolactone for controlled paclitaxel delivery.

    PubMed

    Musiał-Kulik, Monika; Gębarowska, Katarzyna; Kasperczyk, Janusz; Pastusiak, Małgorzata; Janeczek, Henryk; Dobrzyński, Piotr

    2014-01-01

    Bioresorbable, aliphatic polyesters are known in medicine where serve as orthopedic devices (e.g., rods, pins and screws) or sutures and staples in wound closure. Moreover, such materials are extensively stud- ied as scaffolds--three-dimensional structures for tissue engineering but also drug delivery systems (DDS). The aim of this study was to determine the release profile of paclitaxel, one of the anti-inflammatory, antiprolifera- tive and anti-restenotic agent, from biocompatible copolymer of L-lactide and ε-caprolactone that seems to be very attractive especially for minimally invasive surgery due to its potential shape-memory property. The influ- ence of drug on copolymer hydrolytic degradation was also analyzed. Three types of matrices (3%, 5% of PTX and without drug) were prepared by solvent-casting method and degraded in vitro. The physicochemical changes of copolymer were analyzed by means of nuclear magnetic resonance spectroscopy (NMR), gel per- meation chromatography (GPC) and differential scanning calorimetry (DSC). The amount of drug released into media was monitored with the use of high-pressure liquid chromatography (HPLC). Similar drug release pro- files were obtained for matrices with paclitaxel. The drug-containing matrices degraded slightly slower than drug free matrices, regardless PTX content. Results of this work may be helpful in designing new bioresorbable paclitaxel delivery system applied in anti-cancer therapy or drug-eluting stents technology. PMID:25745774

  5. Biomodulation of capecitabine by paclitaxel and carboplatin in advanced solid tumors and adenocarcinoma of unknown primary.

    PubMed

    Mikhail, Sameh; Lustberg, Maryam B; Ruppert, Amy S; Mortazavi, Amir; Monk, Paul; Kleiber, Barbara; Villalona-Calero, Miguel; Bekaii-Saab, Tanios

    2015-11-01

    Paclitaxel and carboplatin upregulate thymidine phosphorylase and thus may provide synergistic antitumor activity in combination with capecitabine (CTX). We, therefore, performed a phase I/II study of CTX. In the phase I study, patients with advanced solid tumors received carboplatin on day 1, paclitaxel on days 1, 8, 15 and capecitabine orally twice a day on days 8-21, every 4 weeks. Phase II patients with advanced adenocarcinoma of unknown primary (ACUP) were treated at the maximal tolerable dose. The phase I study enrolled 29 patients evaluable for dose limiting toxicity. The recommended phase II dose was capecitabine 750 mg/m(2) bid, paclitaxel 60 mg/m(2)/week and carboplatin AUC of 6. There were 9 confirmed responses, 5 partial responses and disease stabilization >3 months in 14 patients. The phase II study was prematurely terminated at 25 patients due to cessation of funding. The objective response rate was 32 % (95 % CI 0.15-0.54), the median progression-free survival 5.5 months (95 % CI 2.8-10.8 months) and the median overall survival 10.8 months (95 % CI 6.0-32.0 months). CTX demonstrated acceptable tolerability and antitumor activity. At the recommended dose level in patients with ACUP, this regimen showed encouraging preliminary activity. PMID:26416564

  6. Antitumour activity of ANG1005, a conjugate between paclitaxel and the new brain delivery vector Angiopep-2

    PubMed Central

    Régina, A; Demeule, M; Ché, C; Lavallée, I; Poirier, J; Gabathuler, R; Béliveau, R; Castaigne, J-P

    2008-01-01

    Background and purpose: Paclitaxel is highly efficacious in the treatment of breast, head and neck, non-small cell lung cancers and ovarian carcinoma. For malignant gliomas, paclitaxel is prevented from reaching its target by the presence of the efflux pump P-glycoprotein (P-gp) at the blood–brain barrier. We investigated the utilization of a new drug delivery system to increase brain delivery of paclitaxel. Experimental approach: Paclitaxel molecules were conjugated to a brain peptide vector, Angiopep-2, to provide a paclitaxel–Angiopep-2 conjugate named ANG1005. We determined the brain uptake capacity, intracellular effects and antitumour properties of ANG1005 in vitro against human tumour cell lines and in vivo in human xenografts. We then determined ANG1005 activity on brain tumours with intracerebral human tumour models in nude mice. Key results: We show by in situ brain perfusion that ANG1005 enters the brain to a greater extent than paclitaxel and bypasses the P-gp. ANG1005 has an antineoplastic potency similar to that of paclitaxel against human cancer cell lines. We also demonstrate that ANG1005 caused a more potent inhibition of human tumour xenografts than paclitaxel. Finally, ANG1005 administration led to a significant increase in the survival of mice with intracerebral implantation of U87 MG glioblastoma cells or NCI-H460 lung carcinoma cells. Conclusions and implications: These results demonstrate the antitumour potential of a new drug, ANG1005, and establish that conjugation of anticancer agents with the Angiopep-2 peptide vector could increase their efficacy in the treatment of brain cancer. PMID:18574456

  7. Co-loaded paclitaxel/rapamycin liposomes: Development, characterization and in vitro and in vivo evaluation for breast cancer therapy.

    PubMed

    Eloy, Josimar O; Petrilli, Raquel; Topan, José Fernando; Antonio, Heriton Marcelo Ribeiro; Barcellos, Juliana Palma Abriata; Chesca, Deise L; Serafini, Luciano Neder; Tiezzi, Daniel G; Lee, Robert J; Marchetti, Juliana Maldonado

    2016-05-01

    Paclitaxel and rapamycin have been reported to act synergistically to treat breast cancer. Albeit paclitaxel is available for breast cancer treatment, the most commonly used formulation in the clinic presents side effects, limiting its use. Furthermore, both drugs present pharmacokinetics drawbacks limiting their in vivo efficacy and clinic combination. As an alternative, drug delivery systems, particularly liposomes, emerge as an option for drug combination, able to simultaneously deliver co-loaded drugs with improved therapeutic index. Therefore, the purpose of this study is to develop and characterize a co-loaded paclitaxel and rapamycin liposome and evaluate it for breast cancer efficacy both in vitro and in vivo. Results showed that a SPC/Chol/DSPE-PEG (2000) liposome was able to co-encapsulate paclitaxel and rapamycin with suitable encapsulation efficiency values, nanometric particle size, low polydispersity and neutral zeta potential. Taken together, FTIR and thermal analysis evidenced drug conversion to the more bioavailable molecular and amorphous forms, respectively, for paclitaxel and rapamycin. The pegylated liposome exhibited excellent colloidal stability and was able to retain drugs encapsulated, which were released in a slow and sustained fashion. Liposomes were more cytotoxic to 4T1 breast cancer cell line than the free drugs and drugs acted synergistically, particularly when co-loaded. Finally, in vivo therapeutic evaluation carried out in 4T1-tumor-bearing mice confirmed the in vitro results. The co-loaded paclitaxel/rapamycin pegylated liposome better controlled tumor growth compared to the solution. Therefore, we expect that the formulation developed herein might be a contribution for future studies focusing on the clinical combination of paclitaxel and rapamycin. PMID:26836480

  8. Overexpression of SOX2 is involved in paclitaxel resistance of ovarian cancer via the PI3K/Akt pathway.

    PubMed

    Li, Yang; Chen, Kangdong; Li, Lei; Li, Rui; Zhang, Juxin; Ren, Wu

    2015-12-01

    Paclitaxel is recommended as a first-line chemotherapeutic agent against ovarian cancer, but drug resistance becomes a major limitation of its success clinically. The key molecule or mechanism associated with paclitaxel resistance in ovarian cancer still remains unclear. Sex-determining region Y-box 2 (SOX2) is of vital importance in the regulation of stem cell proliferation and carcinogenesis. The aim of this study was to evaluate the role of SOX2 in ovarian cancer tumorigenesis and paclitaxel resistance. In the present study, the expression of SOX2 was examined by immunohistochemistry (IHC) and real-time PCR in 40 clinical samples and in SKOV3 cells and SKOV3/TAX cells (paclitaxel-resistant human ovarian adenocarcinoma cell line). The effects of SOX2 knockdown on ovarian cancer cell proliferation, migration, and invasion were also studied. The IHC and real-time PCR results showed that the difference of SOX2 expression between ovarian cancer and the adjacent non-tumorous ovarian tissues was statistically significant. Western blot analysis revealed that the PI3K/Akt signaling pathway was inhibited in cells overexpressing SOX2. Western blot analysis showed that the SOX2 protein was overexpressed in paclitaxel-resistant cells and weakly detectable in paclitaxel-sensitive cells. SOX2 silencing significantly potentiated apoptosis induced by paclitaxel in SKOV3-TR with SOX2 knockdown compared to SKOV3-TR transfected with control small interfering RNA (siRNA). Our work indicates SOX2 will become both a rational indicator of ovarian cancer prognosis and a promising target for ovarian cancer gene therapy. PMID:26159849

  9. Comparison of the binding of anti-tubulin antibody and the fluorescent taxol derivative Flutax-1 to the microtubular system of Tetrahymena.

    PubMed

    Kovács, P; Csaba, G

    2006-09-01

    Using confocal microscopic analysis, FITC-labelled anti-alpha-tubulin antibody and the fluorescent taxol derivative Flutax-1 in fixed and living Tetrahymena pyriformis GL, longitudinal microtubules, oral and somatic cilia, deep fibers, and contractile vacuole pores were equally labeled. While the antibody stained transversal microtubules, these were not labeled by Flutax-1. At the same time, oral cilia were more intensely stained by Flutax-1, than by the antibody. There were no differences in the staining of fixed preparations and living cells. The observations suggest (i) the difference between the MAPs of longitudinal and transversal microtubules which allow or inhibit the binding of the indicator molecules, and (ii) the different functions of these two types of microtubules. PMID:17048696

  10. Phase II study of preoperative paclitaxel/cisplatin with radiotherapy in locally advanced esophageal cancer

    SciTech Connect

    Kim, Dong W.; Blanke, Charles D.; Wu, Huiyun; Shyr, Yu; Berlin, Jordan; Beauchamp, R. Daniel; Chakravarthy, Bapsi . E-mail: bapsi.chak@vanderbilt.edu

    2007-02-01

    Purpose: Preoperative paclitaxel-based chemoradiotherapy may improve the response rates and survival in patients with localized esophageal cancer. We evaluated paclitaxel-based induction chemoradiotherapy in patients with localized esophageal cancer to determine its feasibility, clinical response, pathologic response, and overall survival. Methods and Materials: Between 1995 and 1998, 50 patients were enrolled in this study. At study entry, patients were categorized as either resectable or unresectable according to evaluation by an experienced thoracic surgeon. All patients were treated with paclitaxel 175 mg/m{sup 2} and cisplatin 75 mg/m{sup 2} on Day 1, 29 with radiotherapy to 3,000 cGy in 15 fractions. Resectable patients underwent esophagectomy 4 weeks later. Postoperatively, patients received two cycles of paclitaxel 175 mg/m{sup 2} on Day 1 and 5-fluorouracil 350 mg/m{sup 2} and leucovorin 300 mg on Days 1-3, given every 28 days. Patients who were deemed unsuitable for resection from the outset continued radiotherapy to a total dose of 6,000 cGy. Results: Of the 50 patients, all began neoadjuvant chemoradiotherapy, 40 patients underwent surgery, and 25 patients completed postoperative chemotherapy. A pathologic complete response was seen in 7 patients (17.5%). Patients with a pathologic response had a median survival of 32.4 months vs. 14.4 months for nonresponders (p <0.001). Patients with a clinical response had a median survival of 25.2 months compared with 15.6 months for nonresponders (p = 0.002). At a median follow up of 19.8 months (range 2.4-100.8), the median survival was 20.4 months and the 3-year overall survival rate was 23.2%. Conclusion: Although preoperative cisplatin/paclitaxel with 3,000 cGy was tolerable, this multimodality regimen did not appear to be superior to standard cisplatin/5-fluorouracil-containing regimens and its use is not recommended.

  11. Inhibition of Notch Signaling in Combination with Paclitaxel Reduces Platinum-Resistant Ovarian Tumor Growth

    PubMed Central

    Groeneweg, Jolijn W.; DiGloria, Celeste M.; Yuan, Jing; Richardson, William S.; Growdon, Whitfield B.; Sathyanarayanan, Sriram; Foster, Rosemary; Rueda, Bo R.

    2014-01-01

    Introduction: Ovarian cancer (OvCa) is the most lethal gynecologic malignancy in the United States because of chemoresistant recurrent disease. Our objective was to investigate the efficacy of inhibiting the Notch pathway with a γ-secretase inhibitor (GSI) in an OvCa patient-derived xenograft model as a single agent therapy and in combination with standard chemotherapy. Methods: Immunocompromised mice bearing xenografts derived from clinically platinum-sensitive human ovarian serous carcinomas were treated with vehicle, GSI (MRK-003) alone, paclitaxel and carboplatin (P/C) alone, or the combination of GSI and P/C. Mice bearing platinum-resistant xenografts were given GSI with or without paclitaxel. Gene transcript levels of the Notch pathway target Hes1 were analyzed using RT-PCR. Notch1 and Notch3 protein levels were evaluated. The Wilcoxon rank-sum test was used to assess significance between the different treatment groups. Results: Expression of Notch1 and 3 was variable. GSI alone decreased tumor growth in two of three platinum-sensitive ovarian tumors (p < 0.05), as well as in one of three platinum-sensitive tumors (p = 0.04). The combination of GSI and paclitaxel was significantly more effective than GSI alone and paclitaxel alone in all platinum-resistant ovarian tumors (all p < 0.05). The addition of GSI did not alter the effect of P/C in platinum-sensitive tumors. Interestingly, although the response of each tumor to chronic GSI exposure did not correlate with its endogenous level of Notch expression, GSI did negatively affect Notch signaling in an acute setting. Conclusion: Inhibiting the Notch signaling cascade with a GSI reduces primary human xenograft growth in vivo. GSI synergized with conventional cytotoxic chemotherapy only in the platinum-resistant OvCa models with single agent paclitaxel. These findings suggest inhibition of the Notch pathway in concert with taxane therapy may hold promise for treatment of platinum-resistant OvCa. PMID:25072022

  12. CX3CR1-Mediated Akt1 Activation Contributes to the Paclitaxel-Induced Painful Peripheral Neuropathy in Rats.

    PubMed

    Li, Dai; Chen, Hui; Luo, Xiao-Huan; Sun, Yang; Xia, Wei; Xiong, Yuan-Chang

    2016-06-01

    Painful peripheral neuropathy is a serious dose-limiting side effect of paclitaxel therapy, which unfortunately often happens during the optimal clinical management of chemotherapy in cancer patients. Currently the underlying mechanisms of the painful peripheral neuropathy remain largely unknown. Here, we found that paclitaxel treatment (3 × 8 mg/kg, cumulative dose 24 mg/kg) upregulated the expression of CX3CR1 and phosphorylated Akt1 in DRG and spinal dorsal horn. Blocking of Akt1 pathway activation with different inhibitor (MK-2206 or LY294002) significantly attenuated mechanical allodynia and thermal hyperalgesia induced by paclitaxel. Furthermore, inhibition of CX3CR1 by using neutralizing antibody not only prevented Akt1 activation in DRG and spinal dorsal horn but also alleviated pain-related behavior induced by paclitaxel treatment. This study suggested that CX3CR1/Akt1 signaling pathway may be a potential target for prevention and reversion of the painful peripheral neuropathy induced by paclitaxel. PMID:26961886

  13. Apoptotic effect of cordycepin combined with cisplatin and/or paclitaxel on MA-10 mouse Leydig tumor cells

    PubMed Central

    Kang, Fu-Chi; Chen, Pei-Jung; Pan, Bo-Syong; Lai, Meng-Shao; Chen, Yung-Chia; Huang, Bu-Miin

    2015-01-01

    Background Chemotherapy is not limited to a single treatment, and the evidence demonstrates that different drug combinations can have positive results in patients. In this study, we sought to determine whether cordycepin combined with cisplatin and/or paclitaxel would have an additive effective on inducing apoptosis in mouse Leydig tumor cells, and the mechanisms were also briefly examined. Methods The additive effects of cordycepin combined with cisplatin and/or paclitaxel on apoptosis in MA-10 cells were investigated by monitoring changes in morphological characteristics and examining cell viability, flow cytometry assays, and Western blot analyses. Results Combination of cordycepin plus cisplatin and/or paclitaxel for 12 and 24 hours induced apoptotic features in MA-10 cells. The MTT assay showed that the combination treatment reduced the viability of MA-10 cells in a dose-dependent manner, with additive effects. Cell cycle analysis showed that combination treatment significantly increased subG1 phase cell numbers in MA-10 cells, indicating apoptosis. Moreover, cordycepin plus cisplatin and/or paclitaxel significantly induced cleavage of caspase-8, caspase-9, caspase-3, and poly ADP-ribose polymerase, and phosphorylation of c-Jun NH2-terminal kinase, extracellular signal-regulated kinase, p38, and p53 proteins in MA-10 cells. Conclusion Cordycepin plus cisplatin and/or paclitaxel can have an additive effect on apoptosis in MA-10 cells, with activation of caspase, mitogen-activated protein kinase, and p53 signal pathways. PMID:26366090

  14. Direct comparison of two albumin-based paclitaxel-loaded nanoparticle formulations: is the crosslinked version more advantageous?

    PubMed

    Li, Chunlei; Li, Yanhui; Gao, Yuqing; Wei, Na; Zhao, Xi; Wang, Caixia; Li, Yongfeng; Xiu, Xian; Cui, Jingxia

    2014-07-01

    Nanoparticles using albumin as particle matrix have entered the mainstream of drug delivery. It was reported that non-crosslinked albumin nanoparticles were unstable in circulation and could deliver drugs into tumor through gp60/SPARC pathway; in contrast, the delivery of drugs with stable nanoparticles was dependent on enhanced permeability and retention effect. Thus, it is questionable which kind of nanoparticles was more advantageous. Two versions of albumin-bound paclitaxel nanoparticles were prepared. In vitro, the non-crosslinked particles could rapidly disintegrate and the crosslinked was stable. The pharmacokinetics of both formulations was different especially at early time and the non-crosslinked particles were cleared rapidly. After non-crosslinked particle treatment paclitaxel had a tendency to accumulate into heart and kidney and following therapy with the crosslinked particles, paclitaxel was liable to be delivered into lung, spleen and liver. The delivery efficiency of paclitaxel into tumor following the non-crosslinked particle treatment was greater than that of the crosslinked (p<0.05), thus resulting in a considerably improved antineoplastic activity. Moreover, the non-crosslinked formulation was only slightly more toxic. It was concluded that the non-crosslinked formulation was more advantageous for the delivery of paclitaxel and our conclusion might be generalized to other lipophilic drugs delivered with albumin nanoparticles. PMID:24709221

  15. Synthesis and biological evaluation of a peptide-paclitaxel conjugate which targets the integrin αvβ₆.

    PubMed

    Li, Shunzi; Gray, Bethany Powell; McGuire, Michael J; Brown, Kathlynn C

    2011-09-15

    The integrin α(v)β(6) is an emergent biomarker for non-small cell lung cancer (NSCLC) as well as other carcinomas. We previously developed a tetrameric peptide, referred to as H2009.1, which binds α(v)β(6) and displays minimal affinity for other RGD-binding integrins. Here we report the use of this peptide to actively deliver paclitaxel to α(v)β(6)-positive cells. We synthesized a water soluble paclitaxel-H2009.1 peptide conjugate in which the 2'-position of paclitaxel is attached to the tetrameric peptide via an ester linkage. The conjugate maintains its specificity for α(v)β(6)-expressing NSCLC cells, resulting in selective cytotoxicity. Treatment of α(v)β(6)-positive cells with the conjugate results in cell cycle arrest followed by induction of apoptosis in the same manner as free paclitaxel. However, initiation of apoptosis and the resultant cell death is delayed compared to free drug. The conjugate demonstrates anti-tumor activity in a H2009 xenograft model of NSCLC with efficacy comparable to treatment with free paclitaxel. PMID:21868241

  16. [The effect of L-Glutamine and Shakuyaku-Kanzo-to for paclitaxel-induced myalgia/arthralgia].

    PubMed

    Hasegawa, Kosei; Mizutani, Yasushi; Kuramoto, Hiroyuki; Nagao, Shoji; Masuyama, Hisashi; Hongo, Atsuhi; Kodama, Jyunichi; Yoshinouchi, Mitsuo; Hiramatsu, Yuji; Kudo, Takafumi; Okuda, Hiroyuki

    2002-04-01

    Myalgia/arthralgia is a crucial side effect of paclitaxel, and may become the major dose-limiting side effect. However, this is a situation where there is little effective preventive treatment. L-Glutamine was reported as a neuroprotective agent for vincristine-induced neurotoxicity. In Japan, there have been reports on steroid and Shakuyaku-Kanzou-to (a herbal medicine) for paclitaxel-induced myalgia/arthralgia. This study aimed to compare the effect of L-Glutamine and Shakuyaku-Kanzou-to, and to discuss the validity of these agents for the paclitaxel-induced myalgia/arthralgia. Our results suggested that Shakuyaku-Kanzou-to showed no remarkable effects against paclitaxel-induced myalgia/arthralgia as had been reported before; however, both L-Glutamine and Shakuyaku-Kanzou-to decreased the duration of grade 2 toxicity (CALGB Expanded Common Toxicity Criteria) in comparison with those who were not treated. L-Glutamine and Shakuyaku-Kanzou-to might therefore a preventive effect against moderate or severer myalgia/arthralgia during paclitaxel-treated chemotherapy. Further trials are needed to confirm the value of these drugs. PMID:11977541

  17. [A case of bone marrow carcinomatosis with disseminated intravascular coagulation arising from breast cancer successfully treated with paclitaxel plus bevacizumab].

    PubMed

    Kawai, Hiroshi; Sugimoto, Ryoma; Miyauchi, Syunsaku; Yoshida, Ryosuke; Waki, Naohisa; Hirayama, Shin; Ishizaki, Masahiro; Nishi, Hideyuki; Yamashita, Kazuki

    2014-11-01

    We report a case of bone marrow carcinomatosis with disseminated intravascular coagulation (DIC) originating from metastatic breast cancer that was treated with paclitaxel plus bevacizumab. A woman in her 30s was diagnosed with bone marrow carcinomatosis arising from metastatic breast cancer 2 years previously. Pathologically, estrogen receptor (ER) and progesterone receptor(PgR) / -positive and human epidermal growth factor receptor 2(HER2/neu)-negative scirrhous carcinoma was diagnosed. She improved after treatment with paclitaxel plus bevacizumab and zoledronic acid. Subsequently, she was treated with hormonal therapy(tamoxifen plus luteinizing-hormone-releasing hormone [LH-RH]agonist) for 7 months. Because progressive bone metastasis was identified and tumor markers increased, the patient was administered paclitaxel plus bevacizumab again. Fifteen days after chemotherapy was initiated, DIC developed. Chemotherapy was continued without decreasing the dose, and recombinant human soluble thrombomodulin (rTM) was added. The DIC resolved in 5 days. After 6 courses of paclitaxel plus bevacizumab, improvement of tumor markers and bone metastasis was observed. Paclitaxel plus bevacizumab can be effective for treatment of bone marrow carcinomatosis with DIC originating from metastatic breast cancer. PMID:25731388

  18. Comparison of toxicity profile and tolerability between two standard of care paclitaxel-based adjuvant chemotherapy regimens in breast cancer.

    PubMed

    Alsharedi, Mohamed; Gress, Todd; Dotson, Jennifer; Elmsherghi, Nabiha; Tirona, Maria Tria

    2016-03-01

    In breast cancer, there are two widely used paclitaxel-based adjuvant chemotherapies, either dose dense paclitaxel (ddP) or weekly paclitaxel (wP). To our knowledge, the comparisons of toxicity and tolerability between the two regimens have never been reported in the literature. This is a retrospective single-institution charts review of breast cancer patients who were treated with paclitaxel-based chemotherapy either ddP or wP. In total, 76 and 45 patients with breast cancer received adjuvant standard ddP and wP, respectively. Patient characteristics in both groups were comparable. Our results showed no statistical significant difference in toxicity profile and tolerability between the two regimens. Particularly, chemotherapy-induced peripheral neuropathy (CIPN) was equally observed in both schedules. Furthermore, grade 3 and 4 CIPN was observed in 17 and 18 %, respectively (p = 0.93). In terms of tolerability, both regimens resulted in similar rates of hospitalization and treatment discontinuation. Our data analysis indicates no significant difference in toxicity profile between the two standard paclitaxel regimens in breast cancer. However, this is a small sample-sized retrospective study and further prospective trial with a larger sample size is warranted. PMID:26883934

  19. Autophagy inhibition re-sensitizes pulse stimulation-selected paclitaxel-resistant triple negative breast cancer cells to chemotherapy-induced apoptosis

    PubMed Central

    Wen, Jian; Yeo, Syn; Wang, Chenran; Chen, Song; Sun, Shaogang; Haas, Michael A.; Tu, Wei; Jin, Feng

    2016-01-01

    Chemotherapy is the mainstay of systemic treatment for triple negative breast cancer (TNBC); however, the development of drug resistance limits its effectiveness. Therefore, we investigated the underlying mechanism for drug resistance and potential approaches to overcome it for a more effective treatment for TNBCs. Using a pulse-stimulated selection strategy to mimic chemotherapy administration in the clinic, we developed a new paclitaxel-resistant MDA-MB-231 cell line and analyzed these cells for changes in autophagy activity, and the role and mechanisms of the increased autophagy in promoting drug resistance were determined. We found that the pulse-stimulated selection strategy with paclitaxel resulted in MDA-MB-231 variant cells with enhanced resistance to paclitaxel. These resistant cells were found to have enhanced basal autophagy activity, which confers a cytoprotective function under paclitaxel treatment stress. Inhibition of autophagy enhanced paclitaxel-induced cell death in these paclitaxel-resistant cells. We further revealed that up-regulated autophagy in resistant cells enhanced the clearance of damaged mitochondria. Last, we showed that the paclitaxel-resistant cancer cells acquired cross resistance to epirubicin and cisplatin. Together, these results suggest that combining autophagy inhibition with chemotherapy may be an effective strategy to improve treatment outcome in paclitaxel-resistant TNBC patients. PMID:25638397

  20. The telomere/telomerase binding factor PinX1 regulates paclitaxel sensitivity depending on spindle assembly checkpoint in human cervical squamous cell carcinomas.

    PubMed

    Tian, Xiao-Peng; Qian, Dong; He, Li-Ru; Huang, He; Mai, Shi-Juan; Li, Chang-Peng; Huang, Xiao-Xia; Cai, Mu-Yan; Liao, Yi-Ji; Kung, Hsiang-fu; Zeng, Yi-Xin; Xie, Dan

    2014-10-10

    Paclitaxel is a main ingredient in the combination chemotherapy treatment of advanced human cervical squamous cell carcinomas. We investigated the roles and underlying molecular mechanisms of PinX1 in cervical squamous cell carcinomas (CSCC) cells response to paclitaxel and its clinical significances. The expression dynamics of PinX1 was first examined by immunohistochemistry in 122 advanced CSCC patients treated with cisplatin/paclitaxel chemotherapy. The expression of PinX1 was significantly associated with the effects of cisplatin/paclitaxel chemotherapy in advanced CSCCs (P<0.05). High expression of PinX1 correlated with CSCC's response to cisplatin/paclitaxel chemotherapy, and was an independent predictor of shortened survival (P<0.05). A series of in vivo and in vitro assays were performed to elucidate the function of PinX1 on CSCC cells chemosensitivity to paclitaxel and underlying mechanisms. In CSCC cells, the levels of PinX1 were only associated with the cytotoxicity and sensitivity of paclitaxel, in which knockdown of PinX1 dramatically enhanced paclitaxel cytotoxicity, whereas the reestablishment of PinX1 levels substantially reduced the paclitaxel-induced killing effect. In addition, we identified that the ability of PinX1 to stabilize the tension between sister kinetochores and maintain the spindle assembly checkpoint was the main reason CSCC cells undergo apoptosis when treated with paclitaxel, and further studies demonstrated that shortened distance between sisters kinetochores by nocodazole confers upon PinX1-replenished cells a sensitivity to the death inducing paclitaxel effects. Furthermore, our study of CSCC cells xenografts in nude mice confirmed the role of PinX1 in paclitaxel sensitivity in vivo. Our data reveal that PinX1 could be used as a novel predictor for CSCC patient response to paclitaxel, and the role of PinX1-mediated paclitaxel sensitivity might represent a new direction for the development of a new generation of microtubule drugs. PMID:25045845

  1. A randomized Phase III trial of weekly or 3-weekly doses of nab-paclitaxel versus weekly doses of Cremophor-based paclitaxel in patients with previously treated advanced gastric cancer (ABSOLUTE Trial).

    PubMed

    Koizumi, Wasaburo; Morita, Satoshi; Sakata, Yuh

    2015-03-01

    Paclitaxel is an agent widely used in second-line chemotherapy for advanced gastric cancer. The aim of this trial is to evaluate the efficacy and safety of 3-weekly or weekly doses of nanoparticle albumin-bound-paclitaxel compared with weekly doses of Cremophor-based paclitaxel in patients with unresectable or recurrent gastric cancer refractory to first-line chemotherapy comprising fluoropyrimidines. A total of 730 patients will be enrolled from 72 institutions. The primary endpoint is the overall survival, and the secondary endpoints are progression-free survival, time to treatment failure, overall response rate, disease control rate, quality of life (by using the EQ-5D system) and safety. PMID:25516635

  2. 3,3'-Diindolylmethane potentiates paclitaxel-induced antitumor effects on gastric cancer cells through the Akt/FOXM1 signaling cascade.

    PubMed

    Jin, Hua; Park, Man Hee; Kim, Soo Mi

    2015-04-01

    Gastric cancer is the fourth most common cancer and is one of the leading causes of cancer-related mortality worldwide. Forkhead box M1 (FOXM1) is overexpressed in gastric cancer, suggesting that it is important in gastric cancer oncogenesis. However, no studies have investigated the role of 3,3'-diindolylmethane (DIM), a component of cruciferous vegetables, in the regulation of FOXM1 and its signaling pathway in gastric cancer. Here, we report for the first time that DIM effectively downregulated Akt/FOXM1 in gastric cancer cells. Combination treatment with DIM and paclitaxel significantly and dose-dependently inhibited the proliferation of SNU638 cells when compared to treatment with DIM or paclitaxel alone. Colony formation of SNU638 cells was significantly attenuated by treatment with DIM and paclitaxel, and DIM potentiated the inhibition of colony formation in SNU638 cells by paclitaxel when compared to treatment with a single agent. Treatment with DIM plus paclitaxel substantially increased apoptosis as indicated by increased levels of cleaved polyADP-ribose polymerase (PARP) and cleaved caspase-9 protein. DIM dose-dependently sensitized gastric cancer cells through downregulation of FOXM1 and potentiated the effects of paclitaxel. FOXM1 effector genes such as CDK4, p53 and cyclin D1 were downregulated in gastric cancer cells by combination treatment with DIM and paclitaxel. In addition, DIM significantly and dose-dependently inhibited phosphorylation of Akt and potentiated paclitaxel-induced inhibition of Akt function in gastric cancer cells. Therefore, our results indicate that DIM effectively potentiates the efficacy of chemotherapeutic agents such as paclitaxel by downregulation of the Akt/FOXM1 signaling cascade in gastric cancer cells. Our findings suggest that DIM enhances the therapeutic efficacy of paclitaxel in gastric cancer and is a potential clinical anticancer agent for the prevention and/or treatment of gastric cancer. PMID:25633416

  3. Metformin potentiates the effects of paclitaxel in endometrial cancer cells through inhibition of cell proliferation and modulation of the mTOR pathway.1

    PubMed Central

    Hanna, Rabbie K.; Zhou, Chunxiao; Malloy, Kimberly M.; Gehrig, Paola A; Bae-Jump, Victoria L.

    2012-01-01

    Objectives To examine the effects of combination therapy with metformin and paclitaxel in endometrial cancer cell lines. Methods ECC-1 and Ishikawa endometrial cancer cell lines were used. Cell proliferation was assessed after exposure to paclitaxel and metformin. Cell cycle progression was assessed by flow cytometry. hTERT expression was determined by real-time RT-PCR. Western immunoblotting was performed to determine the effect of metformin/paclitaxel on the mTOR pathway. Results Paclitaxel inhibited proliferation in a dose-dependent manner in both cell lines with IC50 values of 1–5 nM and 5–10 nM for Ishikawa and ECC-1 cells, respectively. Simultaneous exposure of cells to various doses of paclitaxel in combination with metformin (0.5 mM) resulted in a significant synergistic anti-proliferative effect in both cell lines (Combination Index <1). Metformin induced G1 arrest in both cell lines. Paclitaxel alone or in combination with metformin resulted in predominantly G2 arrest. Metformin decreased hTERT mRNA expression while paclitaxel alone had no effect on telomerase activity. Metformin stimulated AMPK phosphorylation and decreased phosphorylation of the S6 protein. In contrast, paclitaxel inhibited AMPK phosphorylation in the ECC-1 cell line and induced phosphorylation of S6 in both cell lines. Treatment with metformin and paclitaxel resulted in decreased phosphorylation of S6 in both cell lines but only had an additive effect on AMPK phosphorylation in the ECC-1 cell line. Conclusions Metformin potentiates the effects of paclitaxel in endometrial cancer cells through inhibition of cell proliferation and modulation of the mTOR pathway. This combination may be a promising targeted therapy for endometrial cancer. PMID:22252099

  4. Does adding intraperitoneal paclitaxel to standard intraperitoneal regimen yield incremental survival? A propensity score-matched cohort study.

    PubMed

    Chang, Yen-Hou; Lu, Chien-Hsing; Yen, Ming-Shyen; Lee, Wai-Hou; Chang, Yi; Chang, Wei-Pin; Chuang, Chi-Mu

    2016-01-01

    We recruited consecutive patients with stage III epithelial ovarian, tubal, and peritoneal cancers who had optimal residual tumor after primary cytoreductive surgery and who received intraperitoneal chemotherapy between 2002 and 2012. Two propensity score-matched sample cohorts were created. We found that the addition of paclitaxel as a second intraperitoneal agent on a 3-week dosing schedule did not yield significant incremental survival benefits over the intraperitoneal delivery of a single cisplatin-based regimen. If our findings could be confirmed by a prospective randomized study, then it would be interesting to explore the efficacy of shifting back to a dose-dense intraperitoneal delivery of paclitaxel or a dose-dense delivery of a new formulation of paclitaxel for the patients with stage III epithelial ovarian, tubal, and peritoneal cancers. PMID:27160669

  5. Cellular aggregation is a key parameter associated with long term variability in paclitaxel accumulation in Taxus suspension cultures

    PubMed Central

    Patil, Rohan A.; Kolewe, Martin E.; Roberts, Susan C.

    2012-01-01

    Plant cell cultures provide a renewable source for synthesis and supply of commercially valuable plant-derived products, particularly for secondary metabolites. However, instability in product yields over multiple passages has hampered the efficient and sustainable use of this technology. Paclitaxel accumulation in Taxus cell suspension culture was quantified over multiple passages and correlated to mean aggregate size, extracellular sugar level, ploidy, and cell cycle distribution. Paclitaxel levels varied approximately 6.9-fold over the six-month timeframe investigated. Of all of the parameters examined, only mean aggregate size correlated with paclitaxel accumulation, where a significant negative correlation (r = − 0.75, p < 0.01) was observed. These results demonstrate the relevance of measuring, and potentially controlling, aggregate size during long term culture passages, particularly for plant suspensions where industrially relevant secondary metabolites are not pigmented to enable rapid culture selection. PMID:23439858

  6. Bevacizumab-Induced Inhibition of Angiogenesis Promotes a More Homogeneous Intratumoral Distribution of Paclitaxel, Improving the Antitumor Response.

    PubMed

    Cesca, Marta; Morosi, Lavinia; Berndt, Alexander; Fuso Nerini, Ilaria; Frapolli, Roberta; Richter, Petra; Decio, Alessandra; Dirsch, Olaf; Micotti, Edoardo; Giordano, Silvia; D'Incalci, Maurizio; Davoli, Enrico; Zucchetti, Massimo; Giavazzi, Raffaella

    2016-01-01

    The antitumor activity of angiogenesis inhibitors is reinforced in combination with chemotherapy. It is debated whether this potentiation is related to a better drug delivery to the tumor due to the antiangiogenic effects on tumor vessel phenotype and functionality. We addressed this question by combining bevacizumab with paclitaxel on A2780-1A9 ovarian carcinoma and HT-29 colon carcinoma transplanted ectopically in the subcutis of nude mice and on A2780-1A9 and IGROV1 ovarian carcinoma transplanted orthotopically in the bursa of the mouse ovary. Paclitaxel concentrations together with its distribution by MALDI mass spectrometry imaging (MALDI MSI) were measured to determine the drug in different areas of the tumor, which was immunostained to depict vessel morphology and tumor proliferation. Bevacizumab modified the vessel bed, assessed by CD31 staining and dynamic contrast enhanced MRI (DCE-MRI), and potentiated the antitumor activity of paclitaxel in all the models. Although tumor paclitaxel concentrations were lower after bevacizumab, the drug distributed more homogeneously, particularly in vascularized, non-necrotic areas, and was cleared more slowly than controls. This happened specifically in tumor tissue, as there was no change in paclitaxel pharmacokinetics or drug distribution in normal tissues. In addition, the drug concentration and distribution were not influenced by the site of tumor growth, as A2780-1A9 and IGROV1 growing in the ovary gave results similar to the tumor growing subcutaneously. We suggest that the changes in the tumor microenvironment architecture induced by bevacizumab, together with the better distribution of paclitaxel, may explain the significant antitumor potentiation by the combination. Mol Cancer Ther; 15(1); 125-35. ©2015 AACR. PMID:26494857

  7. Diminished taxol/GTP-stimulated tubulin polymerization in diseased region of brain from patients with late-onset or inherited Alzheimer's disease or frontotemporal dementia with parkinsonism linked to chromosome-17 but not individuals with mild cognitive impairment.

    PubMed

    Boutt, Angela M; Neely, M Diana; Bird, Thomas D; Montine, Kathleen S; Montine, Thomas J

    2005-09-01

    Neuronal microtubules are morphologically abnormal in diseased regions of brain from patients with late-onset Alzheimer's disease (LOAD). Here we tested the hypothesis that tubulin derived from gray matter of patients with multiple forms of dementia was functionally impaired. Following taxol/GTP stimulation of tubulin polymerization of gray matter extracts we observed reduced capacity of tubulin to polymerize in LOAD, but not individuals with mild cognitive impairment (MCI), compared to controls. Moreover, we observed similarly reduced taxol/GTP-stimulated tubulin polymerization from gray matter obtained from patients with AD caused by PSEN2 N141I mutation or frontotemporal dementia with parkinsonism linked to chromosome-17 caused (FTDP-17) by TAU V337M or P301L mutation. Our results show that modification of tubulin function may contribute to intermediate or late stages in the pathogenesis of sporadic and inherited AD as well as FTDP-17. PMID:16155344

  8. Neurosteroid 3α-androstanediol efficiently counteracts paclitaxel-induced peripheral neuropathy and painful symptoms.

    PubMed

    Meyer, Laurence; Patte-Mensah, Christine; Taleb, Omar; Mensah-Nyagan, Ayikoe Guy

    2013-01-01

    Painful peripheral neuropathy belongs to major side-effects limiting cancer chemotherapy. Paclitaxel, widely used to treat several cancers, induces neurological symptoms including burning pain, allodynia, hyperalgesia and numbness. Therefore, identification of drugs that may effectively counteract paclitaxel-induced neuropathic symptoms is crucial. Here, we combined histopathological, neurochemical, behavioral and electrophysiological methods to investigate the natural neurosteroid 3α-androstanediol (3α-DIOL) ability to counteract paclitaxel-evoked peripheral nerve tissue damages and neurological symptoms. Prophylactic or corrective 3α-DIOL treatment (4 mg/kg/2 days) prevented or suppressed PAC-evoked heat-thermal hyperalgesia, cold-allodynia and mechanical allodynia/hyperalgesia, by reversing to normal, decreased thermal and mechanical pain thresholds of PAC-treated rats. Electrophysiological studies demonstrated that 3α-DIOL restored control values of nerve conduction velocity and action potential peak amplitude significantly altered by PAC-treatment. 3α-DIOL also repaired PAC-induced nerve damages by restoring normal neurofilament-200 level in peripheral axons and control amount of 2',3'-cyclic-nucleotide-3'-phosphodiesterase in myelin sheaths. Decreased density of intraepidermal nerve fibers evoked by PAC-therapy was also counteracted by 3α-DIOL treatment. More importantly, 3α-DIOL beneficial effects were not sedation-dependent but resulted from its neuroprotective ability, nerve tissue repairing capacity and long-term analgesic action. Altogether, our results showing that 3α-DIOL efficiently counteracted PAC-evoked painful symptoms, also offer interesting possibilities to develop neurosteroid-based strategies against chemotherapy-induced peripheral neuropathy. This article shows that the prophylactic or corrective treatment with 3α-androstanediol prevents or suppresses PAC-evoked painful symptoms and peripheral nerve dysfunctions in rats. The data suggest that 3α-androstanediol-based therapy may constitute an efficient strategy to explore in humans for the eradication of chemotherapy-induced peripheral neuropathy. PMID:24260511

  9. Paclitaxel and carboplatin in patients with metastatic urothelial cancer: results of a phase II trial.

    PubMed Central

    Zielinski, C. C.; Schnack, B.; Grbovic, M.; Brodowicz, T.; Wiltschke, C.; Steger, G.; Pflüger, H.; Marberger, M.

    1998-01-01

    The present phase II trial was undertaken to assess the efficacy and toxicity of a combination of paclitaxel and carboplatin as first-line chemotherapy in patients with metastatic transitional cell carcinoma of the urothelium. Twenty patients (age range 50-79 years; inclusion criteria: WHO performance status 0-2, no previous cytotoxic treatment) with metastatic transitional cell carcinoma of the urothelium were recruited and received cytotoxic treatment with paclitaxel at a dosage of 175 mg m(-2) administered over a 3-h infusion and carboplatin given at an AUC of 5 mg ml(-1) min (according to creatinine clearance) administered every 21 days. A total of 65% of patients achieved remissions (CR+PR), with CR occurring in 40% of patients. A further 15% of patients experienced stable disease. Remissions occurred after 2.4 +/- 0.8 (mean +/- standard deviation; range two to four) treatment cycles. The mean duration of responses (CR+PR) was 8.5 +/- 5.5 months. After a mean observation period of 11.4 +/- 4.8 months, 16 patients (80%) are alive. Toxicity included alopecia of WHO grade 3 in all patients, leucopenia of WHO grades 1 and 2 in ten patients, grade 3 in eight and grade 4 in two patients and, finally, severe thrombocytopenia grade 3 in only three patients. Non-haematological toxicity consisted of polyneuropathy of WHO grade 1 in 13 patients and grade 2 in five patients. We thus conclude that a combination of paclitaxel and carboplatin at the given dosage and schedule constitutes an active, well-tolerated first-line cytotoxic treatment for patients with metastatic urothelial cancer. PMID:9703285

  10. Analysis of aggregate size as a process variable affecting paclitaxel accumulation in Taxus suspension cultures

    PubMed Central

    Kolewe, Martin E.; Henson, Michael A.; Roberts, Susan C.

    2013-01-01

    Plant cell aggregates have long been implicated in affecting cellular metabolism in suspension culture, yet the rigorous characterization of aggregate size as a process variable and its effect on bioprocess performance has not been demonstrated. Aggregate fractionation and analysis of biomass-associated product is commonly used to assess the effect of aggregation, but we establish that this method is flawed under certain conditions and does not necessarily agree with comprehensive studies of total culture performance. Leveraging recent advances to routinely measure aggregate size distributions, we developed a simple method to manipulate aggregate size and evaluate its effect on the culture as a whole, and found that Taxus suspension cultures with smaller aggregates produced significantly more paclitaxel than cultures with larger aggregates in two cell lines over a range of aggregate sizes, and where biomass accumulation was equivalent prior to elicitation with methyl jasmonate. T. cuspidata P93AF cultures with mean aggregate sizes of 690 μm and 1100 μm produced 22 mg/L and 11 mg/L paclitaxel, respectively, a 2-fold increase for smaller aggregates, and T. cuspidata P991 cultures with mean aggregate sizes of 400 μm and 840 μm produced 6 mg/L and 0.3 mg/L paclitaxel, respectively, an increase of 20-fold for smaller aggregates. These results demonstrate the importance of validating experiments aimed at a specific phenomenon with total process studies, and provide a basis for treating aggregate size as a targeted process variable for rational control strategies. PMID:21692199

  11. Effects of mitochondrial poisons on the neuropathic pain produced by the chemotherapeutic agents, paclitaxel and oxaliplatin.

    PubMed

    Xiao, Wen Hua; Bennett, Gary J

    2012-03-01

    The dose-limiting side effect of taxane, platinum-complex, and other kinds of anticancer drugs is a chronic, distal, bilaterally symmetrical, sensory peripheral neuropathy that is often accompanied by neuropathic pain. Work with animal models of these conditions suggests that the neuropathy is a consequence of toxic effects on mitochondria in primary afferent sensory neurons. If this is true, then additional mitochondrial insult ought to make the neuropathic pain worse. This prediction was tested in rats with painful peripheral neuropathy due to the taxane agent, paclitaxel, and the platinum-complex agent, oxaliplatin. Rats with established neuropathy were given 1 of 3 mitochondrial poisons: rotenone (an inhibitor of respiratory Complex I), oligomycin (an inhibitor of adenosine triphosphate synthase), and auranofin (an inhibitor of the thioredoxin-thioredoxin reductase mitochondrial antioxidant defense system). All 3 toxins significantly increased the severity of paclitaxel-evoked and oxaliplatin-evoked mechano-allodynia and mechano-hyperalgesia while having no effect on the mechano-sensitivity of chemotherapy-naïve rats. Chemotherapy-evoked painful peripheral neuropathy is associated with an abnormal spontaneous discharge in primary afferent A fibers and C fibers. Oligomycin, at the same dose that exacerbated allodynia and hyperalgesia, significantly increased the discharge frequency of spontaneously discharging A fibers and C fibers in both paclitaxel-treated and oxaliplatin-treated rats, but did not evoke any discharge in naïve control rats. These results implicate mitochondrial dysfunction in the production of chemotherapy-evoked neuropathic pain and suggest that drugs that have positive effects on mitochondrial function may be of use in its treatment and prevention. PMID:22244441

  12. The effect of multivalent cations and Tau on paclitaxel-stabilized microtubule assembly, disassembly, and structure.

    PubMed

    Safinya, Cyrus R; Chung, Peter J; Song, Chaeyeon; Li, Youli; Ewert, Kai K; Choi, Myung Chul

    2016-06-01

    In this review we describe recent studies directed at understanding the formation of novel nanoscale assemblies in biological materials systems. In particular, we focus on the effects of multivalent cations, and separately, of microtubule-associated protein (MAP) Tau, on microtubule (MT) ordering (bundling), MT disassembly, and MT structure. Counter-ion directed bundling of paclitaxel-stabilized MTs is a model electrostatic system, which parallels efforts to understand MT bundling by intrinsically disordered proteins (typically biological polyampholytes) expressed in neurons. We describe studies, which reveal an unexpected transition from tightly spaced MT bundles to loose bundles consisting of strings of MTs as the valence of the cationic counter-ion decreases from Z=3 to Z=2. This transition is not predicted by any current theories of polyelectrolytes. Notably, studies of a larger series of divalent counter-ions reveal strong ion specific effects. Divalent counter-ions may either bundle or depolymerize paclitaxel-stabilized MTs. The ion concentration required for depolymerization decreases with increasing atomic number. In a more biologically related system we review synchrotron small angle x-ray scattering (SAXS) studies on the effect of the Tau on the structure of paclitaxel-stabilized MTs. The electrostatic binding of MAP Tau isoforms leads to an increase in the average radius of microtubules with increasing Tau coverage (i.e. a re-distribution of protofilament numbers in MTs). Finally, inspired by MTs as model nanotubes, we briefly describe other more robust lipid-based cylindrical nanostructures, which may have technological applications, for example, in drug encapsulation and delivery. PMID:26684364

  13. Multifunctional liposomes loaded with paclitaxel and artemether for treatment of invasive brain glioma.

    PubMed

    Li, Xiu-Ying; Zhao, Yao; Sun, Meng-Ge; Shi, Ji-Feng; Ju, Rui-Jun; Zhang, Cheng-Xiang; Li, Xue-Tao; Zhao, Wei-Yu; Mu, Li-Min; Zeng, Fan; Lou, Jin-Ning; Lu, Wan-Liang

    2014-07-01

    Invasive brain glioma is the most lethal type of cancer and is highly infiltrating. This leads to an extremely poor prognosis and makes complete surgical removal of the tumor virtually impossible. Non-penetration of therapeutic drugs across the blood-brain barrier (BBB), brain cancer stem cells (CSCs), and brain cancer vasculogenic mimicry (VM) results in relapse after surgical and radio therapy. We developed a functional targeting chemotherapy for transporting drugs across the BBB, destroying VM channels, and eliminating CSCs and cancer cells in the brain. The studies were undertaken on brain glioma cells in vitro and in brain glioma-bearing rats. Using paclitaxel as the anticancer drug and artemether as the regulator of apoptosis and inhibitor of VM channels, a kind of functional targeting paclitaxel plus artemether liposomes was developed by modifying two new functional materials: a mannose-vitamin E derivative conjugate (MAN-TPGS1000) and a dequalinium-lipid derivative conjugate (DQA-PEG2000-DSPE). The transport mechanism across the BBB was associated with receptor-mediated endocytosis by MAN-TPGS1000 conjugate via glucose transporters and adsorptive-mediated endocytosis by DQA-PEG2000-DSPE conjugate via electric charge-based interactions. The efficacy was related to the destruction of VM channels by regulating VM indicators, as well as the induction of apoptosis in brain cancer cells and CSCs by activating apoptotic enzymes and pro-apoptotic proteins and inhibiting anti-apoptotic proteins. These data suggest that the chemotherapy using functional targeting paclitaxel plus artemether liposomes could provide a new strategy for treating invasive brain glioma. PMID:24726749

  14. Vasculitis resulting from a superficial femoral artery angioplasty with a paclitaxel-eluting balloon.

    PubMed

    Thomas, Shannon D; McDonald, Robert R A; Varcoe, Ramon L

    2014-02-01

    Drug-eluting balloons (DEBs) coated with the antiproliferative agent paclitaxel may improve primary patency by reducing recurrent luminal stenosis. A proportion of the active drug and excipient coating are known to embolize distally, but until now, there have been no reports of adverse events resulting from their use. We report an unusual case of a painful nodular, biopsy specimen-proven vasculitic rash that afflicted the ipsilateral lower limb of a patient after superficial femoral artery treatment with a DEB. This adverse event may have implications for the use of DEB in this and other vascular territories. PMID:23642919

  15. Forkhead box K2 modulates epirubicin and paclitaxel sensitivity through FOXO3a in breast cancer

    PubMed Central

    de Moraes, G Nestal; Khongkow, P; Gong, C; Yao, S; Gomes, A R; Ji, Z; Kandola, N; Delbue, D; Man, E P S; Khoo, U S; Sharrocks, A D; Lam, E W-F

    2015-01-01

    The forkhead transcription factor FOXK2 has recently been implicated in cancer cell proliferation and survival, but a role in cancer chemotherapeutic drug resistance has hitherto not been explored. Here we demonstrate that FOXK2 has a central role in mediating the cytotoxic drug response in breast cancer. Clonogenic and cell viability assays showed that enhanced FOXK2 expression sensitizes MCF-7 breast cancer cells to paclitaxel or epirubicin treatment, whereas FOXK2 depletion by small interfering RNAs (siRNAs) confers drug resistance. Our data also showed that the activation of the tumour suppressor FOXO3a by paclitaxel and epirubicin is mediated through the induction of FOXK2, as depletion of FOXK2 by siRNA limits the induction of FOXO3a by these drugs in MCF-7 cells. Chromatin immunoprecipitation (ChIP) analysis showed that in response to drug treatment, FOXK2 accumulates and binds to the proximal FOXO3a promoter region in MCF-7 cells. Furthermore, we also uncovered that FOXK2 is deregulated and, therefore, can express at high levels in the nucleus of both the paclitaxel and epirubicin drug-resistant MCF-7 cells. Our results showed that ectopically overexpressed FOXK2 accumulates in the nuclei of drug-resistant MCF-7 cells but failed to be recruited to target genes, including FOXO3a. Crucially, we found that FOXO3a is required for the anti-proliferative and epirubicin-induced cytotoxic function of FOXK2 in MCF-7 cells by sulphorhodamine and clonogenic assays. The physiological importance of the regulation of FOXO3a by FOXK2 is further confirmed by the significant correlations between FOXO3a and FOXK2 expression in breast carcinoma patient samples. Further survival analysis also reveals that high nuclear FOXK2 expression significantly associates with poorer clinical outcome, particularly in patients who have received conventional chemotherapy, consistent with our finding that FOXK2 is deregulated in drug-resistant cells. In summary, our results suggest that paclitaxel and epirubicin target the FOXK2 to modulate their cytotoxicity and deregulated FOXK2 confers drug resistance. PMID:26344694

  16. Combination neratinib (HKI-272) and paclitaxel therapy in patients with HER2-positive metastatic breast cancer

    PubMed Central

    Chow, L W-C; Xu, B; Gupta, S; Freyman, A; Zhao, Y; Abbas, R; Vo Van, M-L; Bondarenko, I

    2013-01-01

    Introduction: Neratinib is a potent irreversible pan-ErbB tyrosine kinase inhibitor that has demonstrated antitumour activity and an acceptable safety profile in patients with human epidermal growth factor receptor (HER)-2-positive breast cancer and other solid tumours. Methods: This was a phase I/II, open-label, two-part study. Part 1 was a dose-escalation study to determine the maximum tolerated dose (MTD) of neratinib plus paclitaxel in patients with solid tumours. Part 2 evaluated the safety, efficacy, and pharmacokinetics of the combination at the MTD in patients with HER2-positive breast cancer. Results: Eight patients were included in the dose-escalation study; no dose-limiting toxicities were observed, and an MTD of oral neratinib 240 mg once daily plus intravenous paclitaxel 80 mg m−2 on days 1, 8, and 15 of each 28-day cycle was determined. A total of 102 patients with HER2-positive breast cancer were enrolled in part 2. The overall median treatment duration was 47.9 weeks (range: 0.1–147.3 weeks). Common treatment-emergent adverse events (all grades/grade ⩾3) included diarrhoea (92%/29% none grade 4), peripheral sensory neuropathy (51%/3%), neutropenia (50%/20%), alopecia (46%/0%), leukopenia (41%/18%), anaemia (37%/8%), and nausea (34%/1%). Three (3%) patients discontinued treatment due to an adverse event (mouth ulceration, left ventricular ejection fraction reduction, and acute renal failure). Among the 99 evaluable patients in part 2 of the study, the overall response rate (ORR) was 73% (95% confidence interval (CI): 62.9–81.2%), including 7 (7%) patients who achieved a complete response; an additional 9 (9%) patients achieved stable disease for at least 24 weeks. ORR was 71% among patients with 0/1 prior chemotherapy regimen for metastatic disease and no prior lapatinib, and 77% among those with 2/3 prior chemotherapy regimens for metastatic disease with prior lapatinib permitted. Kaplan–Meier median progression-free survival was 57.0 weeks (95% CI: 47.7–81.6 weeks). Pharmacokinetic analyses indicated no interaction between neratinib and paclitaxel. Conclusion: The combination of neratinib and paclitaxel was associated with higher toxicity than that of neratinib as a single agent, but was manageable with antidiarrhoeal agents and dose reductions in general. The combination therapy also demonstrated a high rate of response in patients with HER2-positive breast cancer. A phase III trial is ongoing to assess the benefit and risk of this combination in the first-line setting. PMID:23632474

  17. Compatibility of Paclitaxel injection diluent with two reduced-phthalate administration sets for the acclaim pump.

    PubMed

    Xu, Q A; Trissel, L A

    1998-01-01

    The purpose of this project was to evaluate the compatibility of paclitaxel admixtures with the two reduced-phthalate administration sets designed for use with the Acclaim Infusion Control Device. The first is a nitroglycerin set composed of polyethylene tubing, while the second is made using tris(2-ethyl-hexyl) trimellitate (TOTM)-plasticized polyvinyl chloride tubing. Both sets utilize a diethylhexyl phthalate (DEHP)-plasicized pumping segment. The potential for extraction of DEHP from the pumping segments and TOTM plasticizer from the plastic matrix by the Cremophor EL surfactant present in the paclitaxel injection was evaluated. Diethylhexyl phthalate and TOTM plasticizer extraction was tested using the paclitaxel diluent at concentrations equivalent to 0.3 and 1.2 mg/mL over three-hour and four-day infusions. All samples were prepared in triplicate in polyolefin bags of 5% dextrose injection and deliverd through the administration sets into glass collection flasks. Both DEHP and TOTM content were determined using high-performance liquid chromatographic methods. None of the admixtures delivered rapidly over three hours or slowly over four days through the TOTM-plasticized set exhibited any detectable TOTM. Similarly, no DEHP was detected in the effluent form either set with the simulated 0.3-mg/mL admixtures delivered over three hours. The simulated 1.2-mg/mL admixture delivered over three hours yielded only a barely detectable, but not quantifiable, trace of DEHP. However, slow delivery of both concentrations over four days through both sets resulted in leached DEHP in concentrations ranging from about 30 to 150 micrograms/mL at both one and four days. The two reduced-phthalate administration sets tested in this study are suitable for the administration of paclitaxel infusions of short duration, for up to three hours. However, the sets cannot be recommended for administration over longer-duration delivery times ranging from one to four days due to leaching of DEHP plasticizer from the pumping segments. PMID:23989703

  18. [A case of stage IV breast cancer with long-term partial response treated with tri-weekly paclitaxel plus bevacizumab].

    PubMed

    Okamoto, Akiko; Nakatsukasa, Katsuhiko; Fujita, Yoshifumi; Sugimoto, Riho; Sakaguchi, Kouichi; Taguchi, Tetsuya

    2015-03-01

    Paclitaxel combined with bevacizumab yields significantly better progression-free survival (PFS) in patients with metastatic breast cancer than paclitaxel alone. Here, we report a case of stage IV breast cancer with multiple liver, lung, and bone metastases maintaining a long-term partial response (PR) with tri-weekly paclitaxel plus bevacizumab administration. A 46- year-old woman treated with endocrine therapy for 21 months for multiple metastases in her lungs and bones detected 4 years after surgery for left breast cancer was referred to our hospital. New metastases were discovered in her liver. She received paclitaxel (l 90 mg/m/(2)) on days 1, 8, and 15 combined with bevacizumab (10 mg/kg) on days 1 and 15 every 4 weeks. However, during the first 3 courses, the administration of paclitaxel on day 8 was postponed to 1 to 2 weeks because of severe neutropenia. We began tri-weekly administration of paclitaxel plus bevacizumab. She continued receiving the treatment for about 1 year, without severe side effects. The PR state with good performance status was maintained. We suggest that the tri-weekly administration of paclitaxel plus bevacizumab is an effective way to maintain long-term efficacy. PMID:25812504

  19. Prospective evaluation of concurrent paclitaxel and radiation therapy after adjuvant doxorubicin and cyclophosphamide chemotherapy for Stage II or III breast cancer

    SciTech Connect

    Burstein, Harold J. . E-mail: hburstein@partners.org; Bellon, Jennifer R.; Galper, Sharon; Lu, H.-M.; Kuter, Irene; Wong, Julia; Gelman, Rebecca; Bunnell, Craig A.; Parker, Leroy M.; Garber, Judy E.; Winer, Eric P.; Harris, Jay R.; Powell, Simon N.

    2006-02-01

    Purpose: To evaluate the safety and feasibility of concurrent radiation therapy and paclitaxel-based adjuvant chemotherapy, given either weekly or every 3 weeks, after adjuvant doxorubicin and cyclophosphamide (AC). Methods and Materials: After definitive breast surgery and AC chemotherapy, 40 patients with operable Stage II or III breast cancer received protocol-based treatment with concurrent paclitaxel and radiation therapy. Paclitaxel was evaluated on 2 schedules, with treatment given either weekly x 12 weeks (60 mg/m{sup 2}), or every 3 weeks x 4 cycles (135-175 mg/m{sup 2}). Radiation fields and schedules were determined by the patient's surgery and pathology. The tolerability of concurrent therapy was evaluated in cohorts of 8 patients as a phase I study. Results: Weekly paclitaxel treatment at 60 mg/m{sup 2} per week with concurrent radiation led to dose-limiting toxicity in 4 of 16 patients (25%), including 3 who developed pneumonitis (either Grade 2 [1 patient] or Grade 3 [2 patients]) requiring steroids. Efforts to eliminate this toxicity in combination with weekly paclitaxel through treatment scheduling and CT-based radiotherapy simulation were not successful. By contrast, dose-limiting toxicity was not encountered among patients receiving concurrent radiation with paclitaxel given every 3 weeks at 135-175 mg/m{sup 2}. However, Grade 2 radiation pneumonitis not requiring steroid therapy was seen in 2 of 24 patients (8%) treated in such a fashion. Excessive radiation dermatitis was not observed with either paclitaxel schedule. Conclusions: Concurrent treatment with weekly paclitaxel and radiation therapy is not feasible after adjuvant AC chemotherapy for early-stage breast cancer. Concurrent treatment using a less frequent paclitaxel dosing schedule may be possible, but caution is warranted in light of the apparent possibility of pulmonary injury.

  20. The effect of seal oil on paclitaxel induced cytotoxicity and apoptosis in breast carcinoma MCF-7 and MDA-MB-231 cell lines.

    PubMed

    Wang, Zheyu; Butt, Krista; Wang, Lili; Liu, Hu

    2007-01-01

    Some studies have suggested that omega-3 polyunsaturated fatty acids (PUFAs) have an inhibitory effect on the growth of cancer cells and therefore have the potential to increase the efficacy of cancer chemotherapeutic drugs. Considering that omega-3 PUFAs are present abundantly in harp seal oil, we investigated the effect of seal oil on the cytotoxicity and apoptosis induced by paclitaxel in 2 breast cancer cell lines, MCF-7 and MDA-MB-231, respectively. Cytotoxicity evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed that the concentration of paclitaxel that is required for 50% inhibition of cell growth in the presence of seal oil was significantly lower than that of paclitaxel alone. Apoptosis assessment based on morphological changes and DNA fragmentation results indicated that more cells treated with paclitaxel in combination with seal oil underwent apoptosis than with paclitaxel alone. Western blot analysis showed that the expression of B cell lymphoma-2 (Bcl-2) protein, an apoptosis inhibitory protein, in both cell lines was decreased more significant by paclitaxel in combination with seal oil than by paclitaxel alone. In addition, seal oil alone was found to induce apoptosis in both cell lines tested, which appeared to be due to the increased intracellular lipid peroxides produced. It is therefore concluded that paclitaxel in combination with seal oil demonstrated enhanced cytotoxicity and apoptosis in MCF-7 and MDA-MB-231 cells compared to paclitaxel alone, and the use of seal oil may be beneficial in the treatment of breast cancer. PMID:17640170

  1. Paclitaxel-loaded iron platinum stealth immunomicelles are potent MRI imaging agents that prevent prostate cancer growth in a PSMA-dependent manner

    PubMed Central

    Taylor, Robert M; Sillerud, Laurel O

    2012-01-01

    Background and methods: Problems with the clinical management of prostate cancer include the lack of both specific detection and efficient therapeutic intervention. We report the encapsulation of superparamagnetic iron platinum nanoparticles (SIPPs) and paclitaxel in a mixture of polyethyleneglycolated, fluorescent, and biotin-functionalized phospholipids to create multifunctional SIPP-PTX micelles (SPMs) that were conjugated to an antibody against prostate-specific membrane antigen (PSMA) for the specific targeting, magnetic resonance imaging (MRI), and treatment of human prostate cancer xenografts in mice. Results: SPMs were 45.4 ± 24.9 nm in diameter and composed of 160.7 ± 22.9 μg/mL iron, 247.0 ± 33.4 μg/mL platinum, and 702.6 ± 206.0 μg/mL paclitaxel. Drug release measurements showed that, at 37°C, half of the paclitaxel was released in 30.2 hours in serum and two times faster in saline. Binding assays suggested that PSMA-targeted SPMs specifically bound to C4-2 human prostate cancer cells in vitro and released paclitaxel into the cells. In vitro, paclitaxel was 2.2 and 1.6 times more cytotoxic than SPMs to C4-2 cells at 24 and 48 hours of incubation, respectively. After 72 hours of incubation, paclitaxel and SPMs were equally cytotoxic. SPMs had MRI transverse relaxivities of 389 ± 15.5 Hz/mM iron, and SIPP micelles with and without drug caused MRI contrast enhancement in vivo. Conclusion: Only PSMA-targeted SPMs and paclitaxel significantly prevented growth of C4-2 prostate cancer xenografts in nude mice. Furthermore, mice injected with PSMA-targeted SPMs showed significantly more paclitaxel and platinum in tumors, compared with nontargeted SPM-injected and paclitaxel-injected mice. PMID:22915856

  2. The effect of seal oil on paclitaxel induced cytotoxicity and apoptosis in breast carcinoma MCF-7 and MDA-MB-231 cell lines.

    TOXLINE Toxicology Bibliographic Information

    Wang Z; Butt K; Wang L; Liu H

    2007-01-01

    Some studies have suggested that omega-3 polyunsaturated fatty acids (PUFAs) have an inhibitory effect on the growth of cancer cells and therefore have the potential to increase the efficacy of cancer chemotherapeutic drugs. Considering that omega-3 PUFAs are present abundantly in harp seal oil, we investigated the effect of seal oil on the cytotoxicity and apoptosis induced by paclitaxel in 2 breast cancer cell lines, MCF-7 and MDA-MB-231, respectively. Cytotoxicity evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed that the concentration of paclitaxel that is required for 50% inhibition of cell growth in the presence of seal oil was significantly lower than that of paclitaxel alone. Apoptosis assessment based on morphological changes and DNA fragmentation results indicated that more cells treated with paclitaxel in combination with seal oil underwent apoptosis than with paclitaxel alone. Western blot analysis showed that the expression of B cell lymphoma-2 (Bcl-2) protein, an apoptosis inhibitory protein, in both cell lines was decreased more significant by paclitaxel in combination with seal oil than by paclitaxel alone. In addition, seal oil alone was found to induce apoptosis in both cell lines tested, which appeared to be due to the increased intracellular lipid peroxides produced. It is therefore concluded that paclitaxel in combination with seal oil demonstrated enhanced cytotoxicity and apoptosis in MCF-7 and MDA-MB-231 cells compared to paclitaxel alone, and the use of seal oil may be beneficial in the treatment of breast cancer.

  3. Analgesic effect of magnetic stimulation on paclitaxel-induced peripheral neuropathic pain in mice.

    PubMed

    Ami, Nozomi; Okamoto, Kazuo; Oshima, Hidehiko

    2012-06-21

    Peripheral neuropathies are common side effects of chemotherapeutic drugs, including taxanes, platinum-based drugs, vinca alkaloids, and thalidomide. The most common symptoms are numbness, tingling and/or burning pain in a stocking-glove distribution. Severe peripheral neuropathies result in dose reductions, a change in chemotherapy regimen, or early cessation of chemotherapy. There are no proven interventions to prevent or treat chemotherapy-induced peripheral neuropathy. We designed and built a unique magnetic stimulator to clarify the effects of magnetic stimulation in the mouse paclitaxel-induced peripheral neuropathic pain model. Magnetic stimulation significantly reversed paclitaxel-induced mechanical hyperalgesia. The analgesic efficacy of magnetic stimulation was inhibited by naloxone, a μ opioid receptor antagonist. These findings indicate that the analgesic effect of magnetic stimulation is likely to be mediated by the endogenous opioid system. Furthermore, a combination of magnetic stimulation and pregabalin, a Ca(2+) channel blocker, induced a potent combinational analgesic effect, suggesting that analgesic drug dose reduction might be possible. These findings indicate that there is a potential therapeutic utility for magnetic stimulation in pain relief. PMID:22608074

  4. Endocytosis of fluorescent cyclodextrins by intestinal Caco-2 cells and its role in paclitaxel drug delivery.

    PubMed

    Réti-Nagy, Katalin; Malanga, Milo; Fenyvesi, Éva; Szente, Lajos; Vámosi, György; Váradi, Judit; Bácskay, Ildikó; Fehér, Pálma; Ujhelyi, Zoltán; Róka, Eszter; Vecsernyés, Miklós; Balogh, György; Vasvári, Gábor; Fenyvesi, Ferenc

    2015-12-30

    Cyclodextrins are widely used excipients in pharmaceutical formulations. They are mainly utilized as solubilizers and absorption enhancers, but recent results revealed their effects on cell membranes and pharmacological barriers. In addition to the growing knowledge on their interaction with plasma membranes, it was confirmed that cyclodextrins are able to enter cells by endocytosis. The number of the tested cyclodextrins was limited, and the role of this mechanism in drug absorption and delivery is not known. Our aim was to examine the endocytosis of fluorescently labeled hydroxypropyl-β-cyclodextrin, random methyl-β-cyclodextrin and soluble β-cyclodextrin polymer, and the cellular uptake of the fluorescent paclitaxel derivative-random methyl-β-cyclodextrin complex. The studied cyclodextrin derivatives were able to enter Caco-2 intestinal cells and localized in vesicles in the cytoplasm, while their permeability was very limited through Caco-2 monolayers. We demonstrated for the first time that the fluorescent paclitaxel derivative and rhodamine-labeled random methyl-β-cyclodextrin were detected in the same intracellular vesicles after treating cells with their inclusion complex. These results indicate that the endocytosis of cyclodextrin complexes can contribute to drug absorption processes. PMID:26498369

  5. Release modeling and comparison of nanoarchaeosomal, nanoliposomal and pegylated nanoliposomal carriers for paclitaxel.

    PubMed

    Movahedi, Fatemeh; Ebrahimi Shahmabadi, Hasan; Alavi, Seyed Ebrahim; Koohi Moftakhari Esfahani, Maedeh

    2014-09-01

    Breast cancer is the most prevalent cancer among women. Recently, delivering by nanocarriers has resulted in a remarkable evolution in treatment of numerous cancers. Lipid nanocarriers are important ones while liposomes and archaeosomes are common lipid nanocarriers. In this work, paclitaxel was used and characterized in nanoliposomal and nanoarchaeosomal form to improve efficiency. To increase stability, efficiency and solubility, polyethylene glycol 2000 (PEG 2000) was added to some samples. MTT assay confirmed effectiveness of nanocarriers on MCF-7 cell line and size measuring validated nano-scale of particles. Nanoarchaeosomal carriers demonstrated highest encapsulation efficiency and lowest release rate. On the other hand, pegylated nanoliposomal carrier showed higher loading efficiency and less release compared with nanoliposomal carrier which verifies effect of PEG on improvement of stability and efficiency. Additionally, release pattern was modeled using artificial neural network (ANN) and genetic algorithm (GA). Using ANN modeling for release prediction, resulted in R values of 0.976, 0.989 and 0.999 for nanoliposomal, pegylated nanoliposomal and nanoarchaeosomal paclitaxel and GA modeling led to values of 0.954, 0.951 and 0.976, respectively. ANN modeling was more successful in predicting release compared with the GA strategy. PMID:24867099

  6. A Paclitaxel-Loaded Recombinant Polypeptide Nanoparticle Outperforms Abraxane in Multiple Murine Cancer Models

    PubMed Central

    Bhattacharyya, Jayanta; Bellucci, Joseph J.; Weitzhandler, Isaac; McDaniel, Jonathan R.; Spasojevic, Ivan; Li, Xinghai; Lin, Chao-Chieh; Chi, Jen-Tsan Ashley; Chilkoti, Ashutosh

    2015-01-01

    Packaging clinically relevant hydrophobic drugs into a self-assembled nanoparticle can improve their aqueous solubility, plasma half-life, tumor specific uptake and therapeutic potential. To this end, here we conjugated paclitaxel (PTX) to recombinant chimeric polypeptides (CPs) that spontaneously self-assemble into ~60-nm diameter near-monodisperse nanoparticles that increased the systemic exposure of PTX by 7-fold compared to free drug and 2-fold compared to the FDA approved taxane nanoformulation (Abraxane®). The tumor uptake of the CP-PTX nanoparticle was 5-fold greater than free drug and 2-fold greater than Abraxane. In a murine cancer model of human triple negative breast cancer and prostate cancer, CP-PTX induced near complete tumor regression after a single dose in both tumor models, whereas at the same dose, no mice treated with Abraxane survived for more than 80 days (breast) and 60 days (prostate) respectively. These results show that a molecularly engineered nanoparticle with precisely engineered design features outperforms Abraxane, the current gold standard for paclitaxel delivery. PMID:26239362

  7. Preparation and characterization of a novel conformed bipolymer paclitaxel-nanoparticle using tea polysaccharides and zein.

    PubMed

    Li, Shuqin; Wang, Xiuming; Li, Weiwei; Yuan, Guoqi; Pan, Yuxiang; Chen, Haixia

    2016-08-01

    To improve the aqueous solubility of the anticancer agent paclitaxel (PTX), a newly conformed bipolymer paclitaxel-nanoparticle using tea polysaccharide (TPS) and zein was prepared and characterized. Tea polysaccharide was used as a biopolymer shell and zein was as the core and the optimal formula was subjected to the characteristic study by TEM, DSC, FTIR and in vitro release study. Results showed that the optimal particle was acquired with particle yield at 40.01%, drug loading at 0.12% and diameters around 165nm when the concentration of tea polysaccharide was set at 0.2%, and the amount of PTX:zein=1:10. The particle was a nanoparticle with spherical surface and the encapsulated PTX was in an amorphous form rather than cystalline form. PTX was interacted with zein and polysaccharide through O H and CO groups and it had a sustained release. The results suggested that the novel bipolymer might be a promising agent for PTX delivery and tea polysaccharide was demonstrated its function in drug delivery system. PMID:27112850

  8. [Successful management with S-1 of recurrent gastric cancer after adjuvant chemotherapy with paclitaxel/UFT].

    PubMed

    Tokunaga, Yukihiko; Sasaki, Hirokazu; Saito, Tohru

    2010-04-01

    We report here two cases of recurrent gastric cancer after post operative adjuvant chemotherapy, in which S-1 has been effective to control the recurrence and provided long-term survival. Case 1: A 75-year-old male presented with malaise. Endoscopy showed an advanced gastric cancer. He underwent total gastrectomy with lymph adenectomy and received adjuvant chemotherapy with 3 courses of weekly paclitaxel and 6 months of UFT. An abdominal tumor developed with elevation of tumor markers 1 year and 2 months after surgery. After 5 courses of S-1(100mg/day), the tumor resolved and a complete response(CR)was obtained with decline of the markers for 2 years. Case 2: A 62-year-old male presented with abdominal pain. Endoscopy showed an advanced gastric cancer. He underwent distal gastrectomy with lymph adenectomy. Peritonitis carcinomatosa developed with ascites though adjuvant chemotherapy with UFT had been continued for 6 months after paclitaxel. After 10 courses of S-1(100 mg/day), ascites disappeared with decline of the markers. He has been well without any sign of recurrence or elevation of tumor markers for 2 years. Differences in the 5-fluorouracil concentration of UFT and that of S-1 may explain the effectiveness of S-1 for recurrence of gastric cancer after adjuvant chemotherapy with UFT. PMID:20414030

  9. Sialoganglioside Micelles for Enhanced Paclitaxel Solubility: In Vitro Characterization.

    PubMed

    Heredia, Valeria; Alasino, Roxana V; Leonhard, Victoria; Garro, Ariel G; Maggio, Bruno; Beltramo, Dante M

    2016-01-01

    Efficiency of mono-sialogangliosides to load Paclitaxel (Ptx) has recently been found to depend on the structure of the polysaccharide chain. In this study, we demonstrated that incorporation of only one more sialic acid into the ganglioside molecule, independently of its position, causes a 4-fold increase in Ptx-loading capacity, the maximum being at a 5:1 molar ratio (di-sialoganglioside/Paclitaxel, GD/Ptx). These complexes are stable in solution for at least 3 months, and over 90% of Ptx remains loaded in the micelles after extreme stress conditions such as high-speed centrifugation, lyophilization, or freeze-thaw cycles. Ganglioside micelles protect 50% of the initially loaded Ptx from alkaline hydrolysis after 24 h at pH 10. Dynamic light scattering studies revealed that GD micelles increase their size from 9 to 12 nm when loaded with Ptx. Transmission electron microscopy shows a homogeneous population of spherical micelles either with or without Ptx. In vitro biological activity was similar to that of the free drug. These results provide further options of self-assembled nanostructures of di- and tri-sialogangliosides with a higher loading capacity. PMID:26852858

  10. Pegylated polyelectrolyte nanoparticles containing paclitaxel as a promising candidate for drug carriers for passive targeting.

    PubMed

    Szczepanowicz, Krzysztof; Bzowska, Monika; Kruk, Tomasz; Karabasz, Alicja; Bereta, Joanna; Warszynski, Piotr

    2016-07-01

    Targeted drug delivery systems are of special importance in cancer therapies, since serious side effects resulting from unspecific accumulation of highly toxic chemotherapeutics in healthy tissues can restrict effectiveness of the therapy. In this work we present the method of preparing biocompatible, polyelectrolyte nanoparticles containing the anticancer drug that may serve as a vehicle for passive tumor targeting. The nanoparticles were prepared via direct encapsulation of emulsion droplets in a polyelectrolyte multilayer shell. The oil cores that contained paclitaxel were stabilized by docusate sodium salt/poly-l-lysine surface complex (AOT/PLL) and were encapsulated in shells formed by the LbL adsorption of biocompatible polyelectrolytes, poly-L-glutamic acid (PGA) and PLL up to 5 or 6 layers. The surface of the nanoparticles was pegylated through the adsorption of the pegylated polyelectrolyte (PGA-g-PEG) as the outer layer to prolong the persistence of the nanocarriers in the circulation. The synthesized nanoparticles were stable in cell culture medium containing serum and their average size was 100nm, which makes them promising candidates for passive targeted drug delivery. This notion was further confirmed by the results of studying the biological effects of nanoformulations on two tumor cell lines: mouse colon carcinoma cell line CT26-CEA and the mouse mammary carcinoma cell line 4T1. The empty polyelectrolyte nanoparticles did not affect the viability of the tested cells, whereas encapsulated paclitaxel retained its strong cytotoxic/cytostatic activity. PMID:27037784

  11. Molecular dynamics of paclitaxel encapsulated by salicylic acid-grafted chitosan oligosaccharide aggregates.

    PubMed

    Wang, Xiao-Ying; Zhang, Ling; Wei, Xiao-Hong; Wang, Qi

    2013-02-01

    Chitosan oligosaccharide (COS) derivatives have attracted significant interest in drug delivery systems because of their well-known low toxicity, excellent biocompatibility, and biodegradability. Paclitaxel-loaded nanoparticles based on salicylic acid-grafted chitosan oligosaccharide (COS/SA) were synthesized and characterized. Then, in order to understand the mechanism of the actions of the paclitaxel (PTX) encapsulated by COS/SA, all-atom molecular dynamics simulations were performed to analyze the aggregation of COS/SA molecules. The van der Waals and hydrophobic interactions are the major driving forces for the drug encapsulation process. Electrostatic and hydrogen-bonding interactions also play helpful roles in the COS/SA aggregation. Analyses of the radial distribution function and solvent accessible surface area indicate that the COS/SA nanoparticles are highly hydrosoluble and that the nanoparticles can significantly enhance the aqueous solubility of a hydrophobic drug. Different drug loading systems are also investigated in this work, and the best theoretical drug loading is found to be 10% (w/w). The present work provides insights into the mechanism of the atomic structures of drug-loaded polymeric nanoparticles and presents new perspective for the design of drug delivery systems with desirable properties. PMID:23219327

  12. Ultrasound triggered image-guided drug delivery to inhibit vascular reconstruction via paclitaxel-loaded microbubbles

    PubMed Central

    Zhu, Xu; Guo, Jun; He, Cancan; Geng, Huaxiao; Yu, Gengsheng; Li, Jinqing; Zheng, Hairong; Ji, Xiaojuan; Yan, Fei

    2016-01-01

    Paclitaxel (PTX) has been recognized as a promising drug for intervention of vascular reconstructions. However, it is still difficult to achieve local drug delivery in a spatio-temporally controllable manner under real-time image guidance. Here, we introduce an ultrasound (US) triggered image-guided drug delivery approach to inhibit vascular reconstruction via paclitaxel (PTX)-loaded microbubbles (PLM) in a rabbit iliac balloon injury model. PLM was prepared through encapsulating PTX in the shell of lipid microbubbles via film hydration and mechanical vibration technique. Our results showed PLM could effectively deliver PTX when exposed to US irradiation and result in significantly lower viability of vascular smooth muscle cells. Ultrasonographic examinations revealed the US signals from PLM in the iliac artery were greatly increased after intravenous administration of PLM, making it possible to identify the restenosis regions of iliac artery. The in vivo anti-restenosis experiments with PLM and US greatly inhibited neointimal hyperplasia at the injured site, showing an increased lumen area and reduced the ratio of intima area and the media area (I/M ratio). No obvious functional damages to liver and kidney were observed for those animals. Our study provided a promising approach to realize US triggered image-guided PTX delivery for therapeutic applications against iliac restenosis. PMID:26899550

  13. Paclitaxel antibody conjugates and trehalose for preserving the immunological activity after freeze-drying.

    PubMed

    Jaime, Jairo; Pagé, Michel

    2004-02-01

    Antibodies and anticancer drug-antibody conjugates used in experimental cancer research or clinically must be freeze-dried for preserving the activity and storage at room temperature. This often results in some denaturation and loss of activity. We describe a recovery of the cytotoxic activity of a paclitaxel-mAb immunoconjugate after freeze-drying. The paclitaxel-antibody conjugate specific for ovarian cancer was tested both for its cytotoxicity in vitro and immunological activity after freeze drying in the presence of various preservatives. Results show that the inclusion of trehalose as a stabilizer at concentrations varying from the 0.25 and 0.40 M protected the antibody and saved the pharmacological activity. When PEG alone or with trehalose was used, the immunological and cytotoxic activities recovery were lower. Albumin was not protective. This study shows that the addition of trehalose for freeze drying labile drug is a promising method for storage of large quantities of the immunoconjugates for experimental and therapeutic use. PMID:14965225

  14. Ultrasound triggered image-guided drug delivery to inhibit vascular reconstruction via paclitaxel-loaded microbubbles.

    PubMed

    Zhu, Xu; Guo, Jun; He, Cancan; Geng, Huaxiao; Yu, Gengsheng; Li, Jinqing; Zheng, Hairong; Ji, Xiaojuan; Yan, Fei

    2016-01-01

    Paclitaxel (PTX) has been recognized as a promising drug for intervention of vascular reconstructions. However, it is still difficult to achieve local drug delivery in a spatio-temporally controllable manner under real-time image guidance. Here, we introduce an ultrasound (US) triggered image-guided drug delivery approach to inhibit vascular reconstruction via paclitaxel (PTX)-loaded microbubbles (PLM) in a rabbit iliac balloon injury model. PLM was prepared through encapsulating PTX in the shell of lipid microbubbles via film hydration and mechanical vibration technique. Our results showed PLM could effectively deliver PTX when exposed to US irradiation and result in significantly lower viability of vascular smooth muscle cells. Ultrasonographic examinations revealed the US signals from PLM in the iliac artery were greatly increased after intravenous administration of PLM, making it possible to identify the restenosis regions of iliac artery. The in vivo anti-restenosis experiments with PLM and US greatly inhibited neointimal hyperplasia at the injured site, showing an increased lumen area and reduced the ratio of intima area and the media area (I/M ratio). No obvious functional damages to liver and kidney were observed for those animals. Our study provided a promising approach to realize US triggered image-guided PTX delivery for therapeutic applications against iliac restenosis. PMID:26899550

  15. Synergistic cytotoxicity of oncolytic reovirus in combination with cisplatin–paclitaxel doublet chemotherapy

    PubMed Central

    Roulstone, V; Twigger, K; Zaidi, S; Pencavel, T; Kyula, JN; White, C; McLaughlin, M; Seth, R; Karapanagiotou, EM; Mansfield, D; Coffey, M; Nuovo, G; Vile, RG; Pandha, HS; Melcher, AA; Harrington, KJ

    2016-01-01

    Oncolytic reovirus is currently under active investigation in a range of tumour types. Early phase studies have shown that this agent has modest monotherapy efficacy and its future development is likely to focus on combination regimens with cytotoxic chemotherapy. Indeed, phase I/II clinical trials have confirmed that reovirus can be safely combined with cytotoxic drugs, including a platin—taxane doublet regimen, which is currently being tested in a phase III clinical trial in patients with relapsed/metastatic head and neck cancer. Therefore, we have tested this triple (reovirus, cisplatin, paclitaxel) combination therapy in a panel of four head and neck cancer cell lines. Using the combination index (CI) method, the triple therapy demonstrated synergistic cytotoxicity in vitro in both malignant and non-malignant cell lines. In head and neck cancer cell lines, this was associated with enhanced caspase 3 and 7 cleavage, but no increase in viral replication. In vitro analyses confirmed colocalisation of markers of reovirus infection and caspase 3. Triple therapy was significantly more effective than reovirus or cisplatin—paclitaxel in athymic nude mice. These data suggest that the combination of reovirus plus platin—taxane doublet chemotherapy has significant activity in head and neck cancer and underpin the current phase III study in this indication. PMID:22895509

  16. Paclitaxel-loaded nanoparticles of star-shaped cholic acid-core PLA-TPGS copolymer for breast cancer treatment

    NASA Astrophysics Data System (ADS)

    Tang, Xiaolong; Cai, Shuyu; Zhang, Rongbo; Liu, Peng; Chen, Hongbo; Zheng, Yi; Sun, Leilei

    2013-10-01

    A system of novel nanoparticles of star-shaped cholic acid-core polylactide- d-α-tocopheryl polyethylene glycol 1000 succinate (CA-PLA-TPGS) block copolymer was developed for paclitaxel delivery for breast cancer treatment, which demonstrated superior in vitro and in vivo performance in comparison with paclitaxel-loaded poly( d, l-lactide- co-glycolide) (PLGA) nanoparticles and linear PLA-TPGS nanoparticles. The paclitaxel- or couramin 6-loaded nanoparticles were fabricated by a modified nanoprecipitation method and then characterized in terms of size, surface charge, surface morphology, drug encapsulation efficiency, and in vitro drug release. The CA-PLA-TPGS nanoparticles were found to be spherical in shape with an average size of around 120 nm. The nanoparticles were found to be stable, showing no change in the particle size and surface charge during 90-day storage of the aqueous solution. The release profiles of the paclitaxel-loaded nanoparticles exhibited typically biphasic release patterns. The results also showed that the CA-PLA-TPGS nanoparticles have higher antitumor efficacy than the PLA-TPGS nanoparticles and PLGA nanoparticles in vitro and in vivo. In conclusion, such nanoparticles of star-shaped cholic acid-core PLA-TPGS block copolymer could be considered as a potentially promising and effective strategy for breast cancer treatment.

  17. Bisphosphonates Inhibit Stellate Cell Activity and Enhance Antitumor Effects of Nanoparticle Albumin Bound-Paclitaxel in Pancreatic Ductal Adenocarcinoma

    PubMed Central

    Gonzalez-Villasana, Vianey; Rodriguez-Aguayo, Cristian; Arumugam, Thiruvengadam; Cruz-Monserrate, Zobeida; Fuentes-Mattei, Enrique; Deng, Defeng; Hwang, Rosa F.; Wang, Huamin; Ivan, Cristina; Garza, Raul Joshua; Cohen, Evan; Gao, Hui; Armaiz-Pena, Guillermo N.; Monroig-Bosque, Paloma del C.; Philip, Bincy; Rashed, Mohammed H.; Aslan, Burcu; Erdogan, Mumin Alper; Gutierrez-Puente, Yolanda; Ozpolat, Bulent; Reuben, James M.; Sood, Anil K.; Logsdon, Craig; Lopez-Berestein, Gabriel

    2014-01-01

    Pancreatic stellate cells (PSCs) have been recognized as the principal cells responsible for the production of fibrosis in PDAC. Recently PSCs have been noted to share characteristics with cells of monocyte-macrophage lineage (MML cells). Thus, we tested whether PSCs could be targeted with the nitrogen-containing bisphosphonates (NBPs) [pamidronate (Pam) or zoledronic acid (ZA)], which are potent MML cell inhibitors. In addition, we tested NBPs treatment combination with nanoparticle albumin-bound paclitaxel (nab-paclitaxel) to enhance antitumor activity. In vitro we observed that PSCs possess α-naphthyl butyrate esterase (ANBE) enzyme activity, a specific marker of MML cells. Moreover NBPs inhibited PSCs proliferation, activation, release of macrophage chemoattractant protein-1 (MCP-1) and type I collagen expression. NBPs also induced PSC apoptosis and cell cycle arrest in the G1 phase. In vivo, NBPs inactivated PSCs; reduced fibrosis; inhibited tumor volume, tumor weight, peritoneal dissemination, angiogenesis, and cell proliferation; and increased apoptosis in an orthotopic murine model of PDAC. These in vivo antitumor effects were enhanced when NBPs were combined with nab-paclitaxel but not gemcitabine (Gem). Our study suggests that targeting PSCs and tumor cells with NBPs in combination with nab-paclitaxel may be a novel therapeutic approach to PDAC. PMID:25193509

  18. Cysteine modified and bile salt based micelles: preparation and application as an oral delivery system for paclitaxel.

    PubMed

    Xu, Wei; Fan, Xiaohui; Zhao, Yanli; Li, Lingbing

    2015-04-01

    The aim of the present study is to construct a cysteine modified polyion complex micelles made of Pluronic F127-chitosan (PF127-CS), Pluronic F127-cysteine (PF127-cysteine) and sodium cholate (NaC) and to evaluate the potential of the micelles as an oral drug delivery system for paclitaxel. Systematic studies on physicochemical properties including size distribution, zeta-potential and morphology were conducted to validate the formation of micelle structure. Compared with Pluronic micelles, drug-loading capacity of PF127-CS/PF127-cysteine/NaC micelles was increased from 3.35% to 12.77%. Both the critical micelle concentration and the stability test confirmed that the PF127-CS/PF127-cysteine/NaC micelles were more stable in aqueous solution than sodium cholate micelles. Pharmacokinetic study demonstrated that when oral administration the area under the plasma concentration-time curve (AUC0-∞) and the absolute bioavailability of paclitaxel-loaded micelles were five times greater than that of the paclitaxel solution. In general, PF127-CS/PF127-cysteine/NaC micelles were proven to be a potential oral drug delivery system for paclitaxel. PMID:25747310

  19. Controlled release of paclitaxel from biodegradable unsaturated poly(ester amide)s/poly(ethylene glycol) diacrylate hydrogels.

    PubMed

    Guo, Kai; Chu, C C

    2007-01-01

    Biodegradable hydrogels (FPBe-G) were synthesized by the photopolymerization of two precursors: FPBe, a fumurate-based unsaturated poly(ester amide) (UPEA), and poly(ethylene glycol) diacrylate (PEG-DA). Depending on the feed ratio of these two precursors, the resultant FPBe-G hydrogels showed different crosslinking levels of network structure, mesh sizes (xi) and matrix morphology. When a lipophilic drug, paclitaxel, was preloaded into FPBe-G hydrogels, the two-month drug-release kinetics from FPBe-G hydrogels in both pure PBS buffer and alpha-chymotrypsin media were measured. The paclitaxel-preloaded FPBe-G hydrogels in a alpha-chymotrypsin solution had significantly faster drug release rate than the corresponding hydrogels in a pure PBS buffer due to an enzyme catalyzed biodegradation of FPBe-G hydrogels. Sustained paclitaxel releases over a two-month period without initial burst release were also achieved by using hydrogels having certain feed ratios of hydrogel precursors. These paclitaxel release data correlated well with the molecular mesh size (xi), molecular weight between cross-links (M(c)) and matrix morphological structure of FPBe-G hydrogels. PMID:17550654

  20. In vitro mutagenicity and blood compatibility of paclitaxel and curcumin in poly (DL-lactide-co-glicolide) films.

    PubMed

    Vieira, Iara Lucia Barbosa Fernandes; de Souza, Debora Cristina Passos; da Silva Coelho, Liliane; Chen, Lee Chen; Guillo, Lidia Andreu

    2013-02-01

    Curcumin is considered to be a potential component for drug-eluting stents due to its anti-inflammatory properties. In this study we compared the mutagenicity and blood compatibility of curcumin to first generation drug eluting stent components: paclitaxel and sirolimus. The Ames test was used to assess mutagenicity. Blood compatibility was tested by measuring platelet activation and fibrinogen adsorption on poly (DL-lactide-co-glycolide, PLGA) films. We discovered that there was no significant increase in the number of revertants/plate following treatment with curcumin (up to 0.5mg/plate) or sirolimus (up to 0.5 μg/plate). However, a significant induction in the frequency of bacterial his(+) revertant colonies by paclitaxel at concentrations of 0.02, 0.05, 0.1, 0.2 and 0.5 μg/plate was observed. We also discovered a significant reduction in platelet activation by PLGA films containing 30% and 50% by weight curcumin. A similar reduction in platelet activation was also observed for PLGA films containing 1% by weight paclitaxel. In addition, we observed an increase of fibrinogen adsorption to PLGA-films containing curcumin. This would compromise the potential use of curcumin as a component of drug-eluting stents. Moreover, our data challenges the current view that paclitaxel does not significantly induce mutagenesis. PMID:23108037

  1. Bisphosphonates inhibit stellate cell activity and enhance antitumor effects of nanoparticle albumin-bound paclitaxel in pancreatic ductal adenocarcinoma.

    PubMed

    Gonzalez-Villasana, Vianey; Rodriguez-Aguayo, Cristian; Arumugam, Thiruvengadam; Cruz-Monserrate, Zobeida; Fuentes-Mattei, Enrique; Deng, Defeng; Hwang, Rosa F; Wang, Huamin; Ivan, Cristina; Garza, Raul Joshua; Cohen, Evan; Gao, Hui; Armaiz-Pena, Guillermo N; Del C Monroig-Bosque, Paloma; Philip, Bincy; Rashed, Mohammed H; Aslan, Burcu; Erdogan, Mumin Alper; Gutierrez-Puente, Yolanda; Ozpolat, Bulent; Reuben, James M; Sood, Anil K; Logsdon, Craig; Lopez-Berestein, Gabriel

    2014-11-01

    Pancreatic stellate cells (PSC) have been recognized as the principal cells responsible for the production of fibrosis in pancreatic ductal adenocarcinoma (PDAC). Recently, PSCs have been noted to share characteristics with cells of monocyte-macrophage lineage (MML cells). Thus, we tested whether PSCs could be targeted with the nitrogen-containing bisphosphonates (NBP; pamidronate or zoledronic acid), which are potent MML cell inhibitors. In addition, we tested NBPs treatment combination with nanoparticle albumin-bound paclitaxel (nab-paclitaxel) to enhance antitumor activity. In vitro, we observed that PSCs possess α-naphthyl butyrate esterase (ANBE) enzyme activity, a specific marker of MML cells. Moreover, NBPs inhibited PSCs proliferation, activation, release of macrophage chemoattractant protein-1 (MCP-1), and type I collagen expression. NBPs also induced PSCs apoptosis and cell-cycle arrest in the G1 phase. In vivo, NBPs inactivated PSCs; reduced fibrosis; inhibited tumor volume, tumor weight, peritoneal dissemination, angiogenesis, and cell proliferation; and increased apoptosis in an orthotopic murine model of PDAC. These in vivo antitumor effects were enhanced when NBPs were combined with nab-paclitaxel but not gemcitabine. Our study suggests that targeting PSCs and tumor cells with NBPs in combination with nab-paclitaxel may be a novel therapeutic approach to PDAC. PMID:25193509

  2. TACC3 depletion sensitizes to paclitaxel-induced cell death and overrides p21WAF-mediated cell cycle arrest.

    PubMed

    Schneider, L; Essmann, F; Kletke, A; Rio, P; Hanenberg, H; Schulze-Osthoff, K; Nürnberg, B; Piekorz, R P

    2008-01-01

    Regulators of the mitotic spindle apparatus are attractive cellular targets for antitumor therapy. The centrosomal protein transforming acidic coiled coil (TACC) 3 is required for spindle assembly and proper chromosome segregation. In this study, we employed an inducible RNA interference approach to downregulate TACC3 expression. We show that TACC3 knock-down in NIH3T3 fibroblasts caused aneuploidy, but failed to overtly impair mitotic progression. TACC3 depletion rather triggered a postmitotic p53-p21(WAF) pathway and led to a reversible cell cycle arrest. Similar effects were induced by low concentrations of paclitaxel, a spindle poison used in antitumor therapy. Interestingly, however, and unlike in TACC3-proficient cells, paclitaxel was able to induce strong polyploidy and subsequent apoptosis in TACC3-depleted cells. Even though paclitaxel treatment was associated with the activation of the survival kinase Akt and an antiapoptotic expression of cytoplasmic p21(WAF) and cyclin D1, this inhibition of cell death was abrogated by depletion of TACC3. Thus, our data identify TACC3 as a potential target to overcome p21(WAF)-associated protection of transformed cells against paclitaxel-induced cell death. PMID:17599038

  3. Top-down and Bottom-up Approaches in Production of Aqueous Nanocolloids of Low Soluble Drug Paclitaxel

    PubMed Central

    Pattekari, P.; Zheng, Z.; Zhang, X.; Levchenko, T.; Torchilin, V.

    2015-01-01

    Nano-encapsulation of poorly soluble anticancer drug was developed with sonication assisted layer-by-layer polyelectrolyte coating (SLbL). We changed the strategy of LbL-encapsulation from making microcapsules with many layers in the walls for encasing highly soluble materials to using very thin polycation / polyanion coating on low soluble nanoparticles to provide their good colloidal stability. SLbL encapsulation of paclitaxel resulted in stable 100-200 nm diameter colloids with high electrical surface ξ-potential (of -45 mV) and drug content in the nanoparticles of 90 wt %. In the top-down approach, nanocolloids were prepared by rupturing powder of paclitaxel using ultrasonication and simultaneous sequential adsorption of oppositely charged biocompatible polyelectrolytes. In the bottom-up approach paclitaxel was dissolved in organic solvent (ethanol or acetone), and drug nucleation was initiated by gradual worsening the solution with the addition of aqueous polyelectrolyte assisted by ultrasonication. Paclitaxel release rates from such nanocapsules were controlled by assembling multilayer shells with variable thicknesses and are in the range of 10-20 hours. PMID:21442095

  4. Paclitaxel/sirolimus combination coated drug-eluting stent: In vitro and in vivo drug release studies

    PubMed Central

    Ma, Xiaodong; Oyamada, Shizu; Gao, Fan; Wu, Tim; Robich, Michael P.; Wu, Hao; Wang, Xingwei; Buchholz, Bryan; McCarthy, Stephen; Gu, Zhiyong; Bianchi, Cesario F.; Sellke, Frank W.; Laham, Roger

    2010-01-01

    Paclitaxel and sirolimus are the two major drugs for the treatment of coronary arterial disease in current drug eluting stents. The two drugs can effectively inhibit the in-stent restenosis through their independent pathways and show synergistic effect in preventing tumor tissue growth. We hypothesize that the combination of the two drugs in a drug eluting stent (DES) can also effectively suppress the neointima growth in the stented artery. The present work was focused on the investigation of paclitaxel/sirolimus combination release profiles from a novel biodegradable polymer (poly (D, L-lactide -co-glycolide) / amorphous calcium phosphate, PLGA/ACP) coated stent both in vitro and in vivo. For the in vitro, the drug releasing profiles were characterized by measuring the drug concentration in a drug release medium (Dulbecco’s phosphate buffered saline, DPBS, pH 7.4) at predetermined time points. For the in vivo, a rat aorta stenting model was employed. The results showed that both paclitaxel and sirolimus had a two-phase release profile both in vitro and in vivo, which is similar to the drug release profile of their individual coated DESs, and there is no evident of interference between two drugs. The data suggest that paclitaxel and sirolimus can be combined pharmacokinetically in a DES for the treatment of coronary arterial diseases. PMID:21126843

  5. Local Intracerebral Administration of Paclitaxel with the Paclimer® Delivery System: Toxicity Study in a Canine Model

    PubMed Central

    Pradilla, Gustavo; Wang, Paul P.; Gabikian, Patrik; Li, Khan; Magee, Carolyn A.; Walter, Kevin A.; Brem, Henry

    2006-01-01

    Introduction: Paclitaxel, a microtubule binding agent with potent anti-glioma activity in vitro, exhibits poor penetrance to the CNS when delivered systemically. To minimize toxicity and reach therapeutic concentrations in the CNS, paclitaxel was previously incorporated into biodegradable microspheres (Paclimer®), and the efficacy of Paclimer® was determined in a rat model of malignant glioma. In this study we report the safety of intracranial Paclimer® in a canine dose escalation toxicity study to prepare its translation into clinical scenarios. Methods: Twelve normal beagle dogs underwent a right parieto-occipital craniectomy and were randomized to receive either Paclimer® at 2-mg/kg (n=5), empty microspheres at 2-mg/kg (n=1), Paclimer® at 20-mg/kg (n=5), or empty microspheres at 20-mg/kg (n=1). Post-operatively, dogs were observed daily for signs of neurotoxicity. Complete blood counts and plasma levels of paclitaxel were obtained weekly. CSF levels and MRI scans were obtained on days14-120. Paclitaxel concentrations were quantified by LC-MS. Results: Animals treated with 20-mg/kg Paclimer® had minimal paclitaxel levels in plasma (range 0-7.84 ng/ml) and CSF (range 0-1.16 ng/ml). Animals treated with 2mg/kg Paclimer® had undetectable levels of paclitaxel in plasma, CSF was not obtained to minimize animal suffering. All animals exhibited normal behavior and weight gain, and were alive post-operatively through the last day of the study (day 60-120) without signs of neurological toxicity. There was no evidence of systemic toxicity or myelosuppression. MR imaging was comparable between Paclimer® animals and controls. Adverse effects included wound infections and a brain abscess, all of which responded to antibiotic therapy, and one ventriculomegaly due to communicating hydrocephalus. Conclusions: Paclimer®-based delivery of paclitaxel is safe for intraparenchymal delivery at the tested doses in normal dogs. PMID:16284923

  6. Fentanyl Enhances Hepatotoxicity of Paclitaxel via Inhibition of CYP3A4 and ABCB1 Transport Activity in Mice

    PubMed Central

    Pan, Jia-Hao; Bi, Bing-Tian; Feng, Kun-Yao; Huang, Wan; Zeng, Wei-An

    2015-01-01

    Fentanyl, a potent opioid analgesic that is used to treat cancer pain, is commonly administered with paclitaxel in advanced tumors. However, the effect of fentanyl on the hepatotoxicity of paclitaxel and its potential mechanism of action is not well studied. The purpose of this study was to investigate the effect of fentanyl on the hepatotoxicity of paclitaxel and its potential mechanisms of action. Pharmacokinetic parameters of paclitaxel were tested using reversed phase high-performance liquid chromatography (RP-HPLC). Aspartate transaminase (AST), alanine aminotransferase (ALT), and mouse liver histopathology were examined. Moreover, the cytotoxicity of anti-carcinogens was examined using 1-(4, 5-dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT), and the intracellular accumulation of doxorubicin and rhodamine 123 was detected by flow cytometry. Furthermore, the expression of ABCB1 and the activity of ABCB1 ATPase and CYP3A4 were also examined. In this study, the co-administration of fentanyl and paclitaxel prolonged the half-life (t1/2) of paclitaxel from 1.455 hours to 2.344 hours and decreased the clearance (CL) from 10.997 ml/h to 7.014 ml/h in mice. Fentanyl significantly increased the levels of ALT in mice to 88.2 U/L, which is more than 2-fold higher than the level detected in the control group, and it increased the histological damage in mouse livers. Furthermore, fentanyl enhanced the cytotoxicity of anti-carcinogens that are ABCB1 substrates and increased the accumulation of doxorubicin and rhodamine 123. Additionally, fentanyl stimulated ABCB1 ATPase activity and inhibited CYP3A4 activity in the liver microsomes of mice. Our study indicates that the obvious hepatotoxicity during this co-administration was due to the inhibition of CYP3A4 activity and ABCB1 transport activity. These findings suggested that the accumulation-induced hepatotoxicity of paclitaxel when it is combined with fentanyl should be avoided. PMID:26633878

  7. Succinyl-proteome profiling of a high taxol containing hybrid Taxus species (Taxus × media) revealed involvement of succinylation in multiple metabolic pathways

    PubMed Central

    Shen, Chenjia; Xue, Jie; Sun, Tao; Guo, Hong; Zhang, Lei; Meng, Yijun; Wang, Huizhong

    2016-01-01

    Protein lysine succinylation, a ubiquitous protein post-translational modification among eukaryotic and prokaryotic cells, represents a vital regulator of various metabolic processes. However, little is known about its functions and cellular distribution in Taxus × media, which is a hybrid Taxus species containing a high content of taxol. In this study, LC-MS/MS was used to identify peptides enriched by immune-purification with high-efficiency succinyl-lysine antibody. A total of 193 succinylated proteins and 325 succinylation sites were identified. The bioinformatics analysis indicated that these succinylated proteins were involved in a wide range of cellular functions from metabolism to protein binding and showed diverse subcellular localizations. Furthermore, our findings suggested that lysine succinylation in Taxus × media involved a diverse array of metabolic processes and protein–protein interactions. Many enzymes involved in multiple metabolic pathways, such as glycolysis, pyruvate metabolism, the tricarboxylic acid cycle and carbon fixation, were identified as substrates for lysine succinylation, suggesting the presence of a common mechanism underlying the participation of succinylation in metabolic regulation. These results provide the first comprehensive view of the succinylome of Taxus × media and may catalyze future biological investigation of succinylation. PMID:26902839

  8. Succinyl-proteome profiling of a high taxol containing hybrid Taxus species (Taxus × media) revealed involvement of succinylation in multiple metabolic pathways.

    PubMed

    Shen, Chenjia; Xue, Jie; Sun, Tao; Guo, Hong; Zhang, Lei; Meng, Yijun; Wang, Huizhong

    2016-01-01

    Protein lysine succinylation, a ubiquitous protein post-translational modification among eukaryotic and prokaryotic cells, represents a vital regulator of various metabolic processes. However, little is known about its functions and cellular distribution in Taxus × media, which is a hybrid Taxus species containing a high content of taxol. In this study, LC-MS/MS was used to identify peptides enriched by immune-purification with high-efficiency succinyl-lysine antibody. A total of 193 succinylated proteins and 325 succinylation sites were identified. The bioinformatics analysis indicated that these succinylated proteins were involved in a wide range of cellular functions from metabolism to protein binding and showed diverse subcellular localizations. Furthermore, our findings suggested that lysine succinylation in Taxus × media involved a diverse array of metabolic processes and protein-protein interactions. Many enzymes involved in multiple metabolic pathways, such as glycolysis, pyruvate metabolism, the tricarboxylic acid cycle and carbon fixation, were identified as substrates for lysine succinylation, suggesting the presence of a common mechanism underlying the participation of succinylation in metabolic regulation. These results provide the first comprehensive view of the succinylome of Taxus × media and may catalyze future biological investigation of succinylation. PMID:26902839

  9. Hyaluronic acid-coated liposomes for targeted delivery of paclitaxel, in-vitro characterization and in-vivo evaluation.

    PubMed

    Ravar, Fatemeh; Saadat, Ebrahim; Gholami, Mehdi; Dehghankelishadi, Pouya; Mahdavi, Mehdi; Azami, Samira; Dorkoosh, Farid A

    2016-05-10

    Breast cancer is the leading cause of cancer death in women. Chemotherapy is regarded as the most essential strategy in inhibiting the proliferation of tumor cells. Paclitaxel is a widely used taxane; however, the side effects of available Cremophor-based formulations and also the limitations of passive targeting uncovered an essential need to develop tumor-specific targeted nanocarriers. A hyaluronic acid targeted liposomal formulation of paclitaxel was prepared in which, hyaluronic acid was electrostatistically attracted to the surface of liposomes. Liposomes, had a particle size of 106.4±3.2nm, a weakly negative zeta potential of -9.7±0.8mV and an acceptable encapsulation efficiency of 92.1±1.7%. The release profile of liposomes in buffer showed that 95% of PTX was released during 40h. Confocal laser scanning microscopy and flow cytometry analysis showed the greater cellular internalization of coumarin-loaded liposomes compared to free coumarin. MTT assay on 4T1 and T47D cells demonstrated the stronger cytotoxic activity of liposomes in comparison to free paclitaxel. Cell cycle analysis showed that cells were mainly blocked at G2/M phases after 48h treatment with liposomes. In vivo real time imaging on 4T1 tumor-bearing mice revealed that the liposomal formulation mainly accumulated in the tumor area. Liposomes also had better antitumor efficacy against Cremophor-based formulation. In conclusion, hyaluronic acid targeted paclitaxel liposome can serve as a promising targeted formulation of paclitaxel for future cancer chemotherapy. PMID:26968799

  10. A Phase I study of capecitabine, carboplatin, and paclitaxel with external beam radiation therapy for esophageal carcinoma

    SciTech Connect

    Czito, Brian G. . E-mail: czito@radonc.duke.edu; Kelsey, Chris R.; Hurwitz, Herbert I.; Willett, Chris G.; Morse, Michael A.; Blobe, Gerard C.; Fernando, Nishan H.; D'Amico, Thomas A.; Harpole, David H.; Honeycutt, Wanda R.N.; Yu Daohai; Bendell, Johanna C.

    2007-03-15

    Purpose: Concurrent chemotherapy and radiation therapy (RT) are used to treat patients with esophageal cancer. The optimal combination of chemotherapeutic agents with RT is undefined. We evaluated a combination of capecitabine, carboplatin, and paclitaxel with RT in a phase I study. Methods and Materials: Patients with squamous cell carcinoma or adenocarcinoma of the esophagus initially received capecitabine, carboplatin, and paclitaxel with RT (1.8 Gy daily to 50.4 Gy). After completion, patients were restaged and evaluated for surgery. Primary endpoints included determination of dose-limiting toxicities (DLT) and a recommended phase II dose, non-DLT, and preliminary radiographic and pathologic response rates. Results: Thirteen patients were enrolled (10 men, 3 women). All were evaluable for toxicity and efficacy. Two of 3 patients at dose level 1 (capecitabine 825 mg/m{sup 2} twice daily on RT days, carboplatin area under the curve (AUC) 2 weekly, paclitaxel 60 mg/m{sup 2} weekly) had DLT (both Grade 4 esophagitis). Of these 3, 2 underwent esophagectomy and had pathologic complete response (pCR). Ten patients were then enrolled at dose level -1 (capecitabine 600 mg/m{sup 2} twice daily, carboplatin AUC 1.5, paclitaxel 45 mg/m{sup 2}). Overall, 3 of 10 patients at dose level -1 developed DLT (2 Grade 3 esophagitis, 1 Grade 3 hypotension). Esophagectomy was performed in 6 of 10 patients. All patients had pathologic downstaging and 2 of 6 had pCR. Conclusions: The maximally tolerated/recommended phase II doses were capecitabine 600 mg/m{sup 2} twice daily, carboplatin AUC 1.5 weekly, and paclitaxel 45 mg/m{sup 2} weekly with RT to 50.4 Gy. In our small study, this regimen appears active but is accompanied by significant toxicities, primarily esophagitis.

  11. Overexpression of stathmin is resistant to paclitaxel treatment in patients with non-small cell lung cancer.

    PubMed

    Sun, Ruifang; Liu, Zhigang; Wang, Lumin; Lv, Weidong; Liu, Jia; Ding, Caixia; Yuan, Yong; Lei, Guangyan; Xu, Changfu

    2015-09-01

    Paclitaxel can exert therapeutic effects by interacting with microtubules. Stathmin and β-III-tubulin, which have impact on microtubule activity, are believed to be involved in the chemotherapy. The purpose of the present study was to evaluate the associations between stathmin and β-III-tubulin expression and treatment response and survivals in patients with non-small cell lung cancer (NSCLC). Two hundred thirty-eight patients who were treated by platinum-based chemotherapy were enrolled in this study, among them, 111 patients also received paclitaxel treatment. Formalin-fixed and paraffin-embedded tumor tissues were collected for messenger RNA (mRNA) and protein detection. We assessed the associations of the two molecules with treatment response and survival outcome. High level of stathmin exhibited poor response to chemotherapy (for mRNA, P = 0.041; for protein, P = 0.017). Overexpression of stathmin was associated with shorter overall survival (for mRNA, P = 0.012; for protein, P = 0.014) and progression-free survival (for mRNA, P = 0.039; for protein, P = 0.022). Of note, this association was only observed in patients who were treated by both platinum and paclitaxel. Similar effects were not observed for β-III-tubulin. The findings demonstrated that paclitaxel effect may be interfered with stathmin; overexpression of stathmin is a predictive marker for a worse prognosis in patients with NSCLC who were treated by both platinum and paclitaxel chemotherapy. PMID:25894372

  12. Poly (?-glutamic acid) based combination of water-insoluble paclitaxel and TLR7 agonist for chemo-immunotherapy.

    PubMed

    Seth, Anushree; Heo, Min Beom; Lim, Yong Taik

    2014-09-01

    Advanced anti-cancer regimens are being introduced for more effective cancer treatment with improved life expectancy. In this research, immuno-stimulating agent toll-like receptor-7 (TLR-7) agonist-imiquimod and low dose chemotherapeutic agent-paclitaxel were synergized to demonstrate tumor therapy along with anti-tumor memory effect. Both therapeutic agents being water insoluble were dispersed in water with the help of water soluble polymer: poly (?-glutamic acid) (?-PGA) using a co-solvent systems leading to formation of micro-dispersions of drugs. Paclitaxel and imiquimod formed crystalline microstructures in the size range of 2-3?m and were stably dispersed in ?-PGA matrix for more than 6 months. Paclitaxel and combination of paclitaxel and imiquimod had significant tumor killing effect in-vitro on various tumor cell lines, while antigen presenting cells (dendritic cells-DCs) treated with the same concentration of imiquimod along with the combination led to enhanced proliferation (250%). In DCs, enhanced secretion of pro-inflammatory and Th1 cytokines was observed in cells co-treated with paclitaxel and imiquimod dispersed in ?-PGA. When administered by intra-tumoral injection in mouse melanoma tumor model, the treatment with combination exemplified drastic inhibition of tumor growth leading to 70% survival as compared to individual components with 0% survival at day 41. The anti-tumor response generated was also found to have systemic memory response since the vaccinated mice significantly deferred secondary tumor development at distant site 6 weeks after treatment. The relative number and activation status of DCs in-vivo was found to be dramatically increased in case of mice treated with combination. The dramatic inhibition of tumor treated with combination is expected to be mediated by both chemotherapeutic killing of tumor cells followed by uptake of released antigen by the DCs and due to enhanced proliferation and activation of the DCs. PMID:24954733

  13. SU2C Phase Ib Study of Paclitaxel and MK-2206 in Advanced Solid Tumors and Metastatic Breast Cancer

    PubMed Central

    Gonzalez-Angulo, Ana M.; Krop, Ian; Akcakanat, Argun; Chen, Huiqin; Liu, Shuying; Li, Yisheng; Culotta, Kirk S.; Tarco, Emily; Piha-Paul, Sarina; Moulder-Thompson, Stacy; Velez-Bravo, Vivianne; Sahin, Aysegul A.; Doyle, Laurence A.; Do, Kim-Anh; Winer, Eric P.; Mills, Gordon B.; Kurzrock, Razelle

    2015-01-01

    Background: There is preclinical synergism between taxanes and MK-2206. We aim to determine the maximum tolerated dose, safety, and activity of combining MK-2206 and paclitaxel in metastatic cancer. Methods: Patients received weekly doses of paclitaxel at 80mg/m2 on day 1, followed by MK-2206 orally on day 2 escalated at 90mg, 135mg, and 200mg. Treatment continued until progression, excessive toxicity, or patient request. Blood and tissue were collected for pharmacokinetic and pharmacodynamics markers. A cycle consisted of three weeks of therapy. Dose-limiting toxicity (DLT) was defined as unacceptable toxicity during the first cycle. All statistical tests were two-sided. Results: Twenty-two patients were treated, nine in dose escalation and 13 in dose expansion. Median age was 55 years. Median number of cycles was four. Dose escalation was completed with no DLT. CTCAE Grade 3 or higher adverse events were fatigue (n = 2), rash (n = 2), hyperglycemia (n = 1), and neutropenia (n = 7). Four patients in the expansion phase required MK-2206 dose reduction. Phase II recommended dose was established as paclitaxel 80mg/m2 weekly on day 1, and MK-2206 135mg weekly on day 2. Paclitaxel systemic exposure was similar in the presence or absence of MK-2206. Plasma MK-2206 concentrations were similar to data from previous phase I monotherapy. There was a statistically significant decrease in expression of pAKT S473 (P = .01) and pAKT T308 (P = .002) after therapy. PI3K/AKT/mTOR downregulation in tumor tissues and circulating markers did not correlate with tumor response or clinical benefit. There were five objective responses, and nine patients had stable disease. Conclusion: MK-2206 was well tolerated with paclitaxel. Preliminary antitumor activity was documented. PMID:25688104

  14. Is there a role of nab-paclitaxel in the treatment of advanced non-small cell lung cancer? The data suggest yes.

    PubMed

    Villaruz, Liza C; Socinski, Mark A

    2016-03-01

    Nab-paclitaxel is a novel therapeutic agent, which was approved in combination with carboplatin in the first-line treatment of advanced non-small cell lung cancer (NSCLC) regardless of histologic subtype in the United States of America by the Food and Drug Administration in 2012 and by the European Commission in 2015. This approval was based on the results of a phase III clinical trial showing superior response rates compared with solvent-based paclitaxel in combination with carboplatin. This review will focus on the early development and clinical data to date supporting the use of nab-paclitaxel in advanced NSCLC. The clinical question central to this review is whether nab-paclitaxel has a place in the current therapeutic landscape of advanced NSCLC. PMID:26875112

  15. Is there a role of nab-paclitaxel in the treatment of advanced non-small cell lung cancer? The data suggest yes

    PubMed Central

    Villaruz, Liza C.; Socinski, Mark A.

    2016-01-01

    Nab-paclitaxel is a novel therapeutic agent, which was approved in combination with carboplatin in the first-line treatment of advanced non-small cell lung cancer (NSCLC) regardless of histologic subtype in the United States of America by the Food and Drug Administration in 2012 and by the European Commission in 2015. This approval was based on the results of a phase III clinical trial showing superior response rates compared with solvent-based paclitaxel in combination with carboplatin. This review will focus on the early development and clinical data to date supporting the use of nab-paclitaxel in advanced NSCLC. The clinical question central to this review is whether nab-paclitaxel has a place in the current therapeutic landscape of advanced NSCLC. PMID:26875112

  16. An antimitotic and antivascular agent BPR0L075 overcomes multidrug resistance and induces mitotic catastrophe in paclitaxel-resistant ovarian cancer cells.

    PubMed

    Wang, Xiaolei; Wu, Erxi; Wu, Jun; Wang, Tian-Li; Hsieh, Hsing-Pang; Liu, Xinli

    2013-01-01

    Paclitaxel plays a major role in the treatment of ovarian cancer; however, resistance to paclitaxel is frequently observed. Thus, new therapy that can overcome paclitaxel resistance will be of significant clinical importance. We evaluated antiproliferative effects of an antimitotic and antivascular agent BPR0L075 in paclitaxel-resistant ovarian cancer cells. BPR0L075 displays potent and broad-spectrum cytotoxicity at low nanomolar concentrations (IC50 = 2-7 nM) against both parental ovarian cancer cells (OVCAR-3, SKOV-3, and A2780-1A9) and paclitaxel-resistant sublines (OVCAR-3-TR, SKOV-3-TR, 1A9-PTX10), regardless of the expression levels of the multidrug resistance transporter P-gp and class III β-tubulin or mutation of β-tubulin. BPR0L075 blocks cell cycle at the G2/M phase in paclitaxel-resistant cells while equal concentration of paclitaxel treatment was ineffective. BPR0L075 induces cell death by a dual mechanism in parental and paclitaxel-resistant ovarian cancer cells. In the parental cells (OVCAR-3 and SKOV-3), BPR0L075 induced apoptosis, evidenced by poly(ADP-ribose) polymerase (PARP) cleavage and DNA ladder formation. BPR0L075 induced cell death in paclitaxel-resistant ovarian cancer cells (OVCAR-3-TR and SKOV-3-TR) is primarily due to mitotic catastrophe, evidenced by formation of giant, multinucleated cells and absence of PARP cleavage. Immunoblotting analysis shows that BPR0L075 treatment induced up-regulation of cyclin B1, BubR1, MPM-2, and survivin protein levels and Bcl-XL phosphorylation in parental cells; however, in resistant cells, the endogenous expressions of BubR1 and survivin were depleted, BPR0L075 treatment failed to induce MPM-2 expression and phosphorylation of Bcl-XL. BPR0L075 induced cell death in both parental and paclitaxel-resistant ovarian cancer cells proceed through caspase-3 independent mechanisms. In conclusion, BPR0L075 displays potent cytotoxic effects in ovarian cancer cells with a potential to overcome paclitaxel resistance by bypassing efflux transporters and inducing mitotic catastrophe. BPR0L075 represents a novel microtubule therapeutic to overcome multidrug resistance and trigger alternative cell death by mitotic catastrophe in ovarian cancer cells that are apoptosis-resistant. PMID:23762410

  17. Poly(ethylene oxide)-block-polyphosphester-based Paclitaxel Conjugates as a Platform for Ultra-high Paclitaxel-loaded Multifunctional Nanoparticles.

    PubMed

    Zhang, Shiyi; Zou, Jiong; Elsabahy, Mahmoud; Karwa, Amolkumar; Li, Ang; Moore, Dennis A; Dorshow, Richard B; Wooley, Karen L

    2013-01-01

    A new type of degradable, nanoscopic polymer assembly containing ultra-high levels of drug loading via covalent attachment within amphiphilic core-shell nanoparticle morphology has been generated as a potentially effective and safe anti-cancer agent. Poly(ethylene oxide)-block-polyphosphoester-based paclitaxel drug conjugates (PEO-b-PPE-g-PTX) were synthesized by rapid, scalable and versatile approach that involves only two steps: organocatalyst-promoted ring-opening-polymerization followed by click reaction-based conjugation of a PTX prodrug. Variations in the polymer-to-PTX stoichiometries allowed for optimization of the conjugation efficiency, the PTX drug loading and the resulting water solubilities of the entire polymer and the PTX content. The PEO-b-PPE-g-PTX formed well-defined micelles in aqueous solution, with a PTX loading capacity as high as 65 wt%, and a maximum PTX concentration of 6.2 mg/mL in water, which is 25000-fold higher than the aqueous solubility of free PTX. The positive cell-killing activity of PEO-b-PPE-g-PTX against several cancer cell lines is demonstrated, and the presence of pendant reactive functionality provides a powerful platform for future work to involve conjugation of multiple drugs and imaging agents to achieve chemotherapy and bioimaging. PMID:25152808

  18. Poly(ethylene oxide)-block-polyphosphester-based Paclitaxel Conjugates as a Platform for Ultra-high Paclitaxel-loaded Multifunctional Nanoparticles†

    PubMed Central

    Zhang, Shiyi; Zou, Jiong; Elsabahy, Mahmoud; Karwa, Amolkumar; Li, Ang; Moore, Dennis A.; Dorshow, Richard B.; Wooley, Karen L.

    2013-01-01

    A new type of degradable, nanoscopic polymer assembly containing ultra-high levels of drug loading via covalent attachment within amphiphilic core-shell nanoparticle morphology has been generated as a potentially effective and safe anti-cancer agent. Poly(ethylene oxide)-block-polyphosphoester-based paclitaxel drug conjugates (PEO-b-PPE-g-PTX) were synthesized by rapid, scalable and versatile approach that involves only two steps: organocatalyst-promoted ring-opening-polymerization followed by click reaction-based conjugation of a PTX prodrug. Variations in the polymer-to-PTX stoichiometries allowed for optimization of the conjugation efficiency, the PTX drug loading and the resulting water solubilities of the entire polymer and the PTX content. The PEO-b-PPE-g-PTX formed well-defined micelles in aqueous solution, with a PTX loading capacity as high as 65 wt%, and a maximum PTX concentration of 6.2 mg/mL in water, which is 25000-fold higher than the aqueous solubility of free PTX. The positive cell-killing activity of PEO-b-PPE-g-PTX against several cancer cell lines is demonstrated, and the presence of pendant reactive functionality provides a powerful platform for future work to involve conjugation of multiple drugs and imaging agents to achieve chemotherapy and bioimaging. PMID:25152808

  19. Bulleyaconitine A depresses neuropathic pain and potentiation at C-fiber synapses in spinal dorsal horn induced by paclitaxel in rats.

    PubMed

    Zhu, He-Quan; Xu, Jing; Shen, Kai-Feng; Pang, Rui-Ping; Wei, Xu-Hong; Liu, Xian-Guo

    2015-11-01

    Paclitaxel, a widely used chemotherapeutic agent, often induces painful peripheral neuropathy and at present no effective drug is available for treatment of the serious side effect. Here, we tested if intragastrical application of bulleyaconitine A (BLA), which has been approved for clinical treatment of chronic pain in China since 1985, could relieve the paclitaxel-induced neuropathic pain. A single dose of BLA attenuated the mechanical allodynia, thermal hyperalgesia induced by paclitaxel dose-dependently. Repetitive administration of the drug (0.4 and 0.8 mg/kg, t.i.d. for 7 d) during or after paclitaxel treatment produced a long-lasting inhibitory effect on thermal hyperalgesia, but not on mechanical allodynia. In consistency with the behavioral results, in vivo electrophysiological experiments revealed that spinal synaptic transmission mediated by C-fiber but not A fiber was potentiated, and the magnitude of long-term potentiation (LTP) at C-fiber synapses induced by the same high frequency stimulation was ~50% higher in paclitaxel-treated rats, compared to the naïve rats. Spinal or intravenous application of BLA depressed the spinal LTP, dose-dependently. Furthermore, patch clamp recordings in spinal cord slices revealed that the frequency but not amplitude of both spontaneous excitatory postsynaptic current (sEPSCs) and miniature excitatory postsynaptic currents (mEPSCs) in lamina II neurons was increased in paclitaxel-treated rats, and the superfusion of BLA reduced the frequency of sEPSCs and mEPSCs in paclitaxel-treated rats but not in naïve ones. Taken together, we provide novel evidence that BLA attenuates paclitaxel-induced neuropathic pain and that depression of spinal LTP at C-fiber synapses via inhibiting presynaptic transmitter release may contribute to the effect. PMID:26376216

  20. Effects of Paclitaxel and Eribulin in Mouse Sciatic Nerve: A Microtubule-Based Rationale for the Differential Induction of Chemotherapy-Induced Peripheral Neuropathy.

    PubMed

    Benbow, Sarah J; Cook, Brett M; Reifert, Jack; Wozniak, Krystyna M; Slusher, Barbara S; Littlefield, Bruce A; Wilson, Leslie; Jordan, Mary Ann; Feinstein, Stuart C

    2016-02-01

    Microtubule targeting agents (MTAs) often lead to treatment limiting and life threatening side effects, including chemotherapy-induced peripheral neuropathy (CIPN). The frequency of severe CIPN varies among different MTAs. Since the microtubule binding interactions and mechanisms of action also vary among MTAs, we hypothesized that these distinct mechanisms may underlie the variability in frequency of severe CIPN. Using a two-week, maximum tolerated dose model, we morphologically and biochemically analyzed sciatic nerves from mice treated with either paclitaxel or eribulin. These drugs differ in their manner of microtubule binding and mechanisms of action and reports indicate paclitaxel also induces a higher frequency of severe CIPN than does eribulin. Morphologically, paclitaxel increased the frequency of observed signs of axon degeneration more significantly than did eribulin. Alternatively, eribulin but not paclitaxel induced occasional myelin "halo" structures. Biochemically, paclitaxel, and eribulin both induced α-tubulin expression (~1.9- and ~2.5-fold, respectively) and tubulin acetylation, a marker for microtubule stability, (~5- and ~11.7-fold, respectively). Eribulin but not paclitaxel-induced EB1 expression ~2.2-fold while paclitaxel but not eribulin mildly suppressed EB3 expression. Both EB proteins are associated with microtubule growth. Eribulin's combination of relatively mild deleterious morphological effects coupled with more potent biochemical changes promoting microtubule stability and growth in mice correlate with lower frequencies of severe CIPN in humans. We suggest that these eribulin-induced effects create a relatively stable microtubule network that compensates, in part, for the toxic anti-cancer effects of the drug, leading to fewer reported incidences of CIPN than for paclitaxel. PMID:26659667

  1. Liquid-Liquid Extraction for Recovery of Paclitaxel from Plant Cell Culture: Solvent Evaluation and Use of Extractants for Partitioning and Selectivity

    PubMed Central

    McPartland, Timothy J.; Patil, Rohan A.; Malone, Michael F.; Roberts, Susan C.

    2012-01-01

    A major challenge in the production of metabolites by plant cells is the separation and purification of a desired product from a number of impurities. An important application of plant cell culture is the biosynthesis of the anti-cancer agent paclitaxel. Liquid-liquid extraction plays a critical role in the recovery of paclitaxel and other valuable plant-derived products from culture broth. In this study, the extraction of paclitaxel and a major unwanted by-product, cephalomannine, from plant cell culture broth into organic solvents is quantified. Potential solvent mixtures show varying affinity and selectivity for paclitaxel over cephalomannine. The partition coefficient of paclitaxel is highest in ethyl acetate and dichloromethane, with measured values of 28 and 25, respectively; however selectivity coefficients are less than 1 for paclitaxel over cephalomannine for both solvents. Selectivity coefficient increases to 1.7 with extraction in n-hexane but the partition coefficient decreases to 1.9. Altering the pH of the aqueous phase results in an increase in both recovery and selectivity using n-hexane, but does not change the results for other solvents significantly. The addition of extractants trioctyl amine (TOA) or tributyl phosphate (TBP) to n-hexane gives significantly higher partition coefficients for paclitaxel (8.6 and 23.7, respectively), but no selectivity. Interestingly, when 20% hexafluorobenzene (HFB) is added to n-hexane, the partition coefficient remains approximately constant but the selectivity coefficient for paclitaxel over cephalomannine improves to 4.5. This significant increase in selectivity early in the purification process has the potential to simplify downstream processing steps and significantly reduce overall purification costs. PMID:22581674

  2. A Phase I Study of Oral Paclitaxel with a Novel P-Glycoprotein Inhibitor, HM30181A, in Patients with Advanced Solid Cancer

    PubMed Central

    Lee, Hyun Jung; Heo, Dae-Seog; Cho, Joo-Youn; Han, Sae-Won; Chang, Hye-Jung; Yi, Hyeon-Gyu; Kim, Tae-Eun; Lee, Se-Hoon; Oh, Do-Youn; Im, Seock-Ah; Jang, In-Jin; Bang, Yung-Jue

    2014-01-01

    Purpose The purpose of this study is to determine the maximum tolerated dose (MTD), safety, pharmacokinetics, and recommended phase II dose of an oral drug composed of paclitaxel and HM30181A, which is an inhibitor of P-glycoprotein, in patients with advanced cancers. Materials and Methods Patients with advanced solid tumors received standard therapy were given the study drug at escalating doses, using a 3+3 design. The study drug was orally administered on days 1, 8, and 15, with a 28-day cycle of administration. The dose of paclitaxel was escalated from 60 to 420 mg/m2, and the dose of HM30181A was escalated from 30-210 mg/m2. Results A total of twenty-four patients were enrolled. Only one patient experienced a doselimiting toxicity—a grade 3 neutropenia that persisted for more than 2 weeks, at 240 mg/m2 of paclitaxel. MTD was not reached. The maximum plasma concentration was obtained at a dose level of 300 mg/m2 and the area under the curve of plasma concentration- time from 0 to the most recent plasma concentration measurement of paclitaxel was reached at a dose level of 420 mg/m2. The absorption of paclitaxel tends to be limited at doses that exceed 300 mg/m2. The effective plasma concentration of paclitaxel was achieved at a dose of 120 mg/m2. Responses of 23 patients were evaluated; 8 (34.8%) had stable disease and 15 (65.2%) had progressive disease. Conclusion The study drug appears to be well tolerated, and the effective plasma concentration of paclitaxel was achieved. The recommended phase II dose for oral paclitaxel is 300 mg/m2. PMID:25038758

  3. Paclitaxel by 1-h infusion in combination with carboplatin in advanced non-small cell lung carcinoma (NSCLC).

    PubMed

    Langer, C J; McAleer, C A; Bonjo, C A; Litwin, S; Millenson, M; Kosierowski, R; Blankstein, K; Alexander, R; Ozols, R F

    2000-01-01

    In our previous study, FCCC 93-024, paclitaxel by 24-h infusion combined with carboplatin yielded a response rate of 62% and median survival of 54 weeks in advanced non-small cell lung cancer (NSCLC). Myelosuppression proved dose-limiting, requiring the routine use of granulocyte-colony stimulating factor (G-CSF). Based on the reported activity of 1-h paclitaxel infusion in NSCLC and minimal myelosuppression at doses of 135 and 200 mg/m2 every 3 weeks and the suggestion of a dose-response relationship, we launched an intrapatient dose escalation trial of combination carboplatin and 1-h paclitaxel. Chemotherapy-naïve patients with advanced NSCLC received paclitaxel 175 mg/m2 1-h and carboplatin dosed to a fixed targeted area under the concentration-time curve (AUC) of 7.5 at three weekly intervals for six cycles. In the absence of grade 4 myelosuppression, paclitaxel was escalated by 35 mg/m2/cycle on an intrapatient basis to a maximum dose of 280 mg/m2 by cycle 4. G-CSF was not routinely used. 57 patients (pts) were accrued from November 1994 through to April 1996. 44 pts (77%) had Eastern Cooperative Oncology Group (ECOG) performance status 1. Median age was 64 (range: 34-80) years. Cumulative peripheral sensory neuropathy proved dose-limiting and prohibitive in the first 20 evaluable patients (cohort A): grade > or = 1 in 15 patients (75%), grade 3 in 6 (30%), generally occurring at paclitaxel doses > or = 215 mg/m2 and obligating 3 patients to have treatment halted in the absence of disease progression. The protocol, therefore, was revised and the initial paclitaxel dose reduced to 135 mg/m2 with intrapatient dose escalation of 40 mg/m2/cycle to a maximum dose of 215 mg/m2, recapitulating the original dosing schema used in FCCC 93-024. 35 patients were enrolled in this second cohort (B); 33 proved evaluable. Whilst 17 (52%) experienced peripheral sensory neuropathy, grade 3 neurotoxicity developed in only 3 (9%). Myelosuppression also was less pronounced, with 42% exhibiting grade 4 granulocytopenia and 30% grade > or = 3 thrombocytopenia in cohort B compared with 70% and 50%, respectively in cohort A. Of the first 22 patients accrued to cohort A, 12 (55%) had major objective responses. Median survival was 48.5 weeks, 1-year survival rate 45% and 2-year survival rate 18%. Of 33 evaluable patients in cohort B, 9 (27%) had major objective responses. Median survival was 46 weeks, 1-year survival rate 47% and 2-year survival rate 12%. Combination paclitaxel by 1-h infusion and carboplatin at a fixed targeted AUC of 7.5 is active in advanced NSCLC. Neurotoxicity, not myelosuppression, proved dose-limiting at paclitaxel doses exceeding 215 mg/m2. Lower doses may be associated with lower response rates, but do not appear to compromise survival. PMID:10741276

  4. A phase I safety and pharmacokinetic study of ABT-263 in combination with carboplatin/paclitaxel in the treatment of patients with solid tumors.

    PubMed

    Vlahovic, Gordana; Karantza, Vassiliki; Wang, Ding; Cosgrove, David; Rudersdorf, Nikita; Yang, Jianning; Xiong, Hao; Busman, Todd; Mabry, Mack

    2014-10-01

    Bcl-2 family proteins are the key regulators of the intrinsic apoptotic pathway, controlling the point-of no-return and setting the threshold to engage the death machinery in response to chemical damage. Bcl-2 proteins have emerged as attractive targets for anti-cancer drug development. Navitoclax is a selective, potent, orally bioavailable, small molecule Bcl-2 inhibitor. Primary endpoints assessed the safety and pharmacokinetic (PK) interactions between navitoclax in combination with carboplatin/paclitaxel or paclitaxel alone in patients with solid tumors The study comprised two arms, one a combination of navitoclax with paclitaxel and carboplatin, the second with navitoclax and paclitaxel alone. Nineteen patients were enrolled in this study. The most frequently reported treatment-emergent AEs were alopecia (57.9 %), anemia (52.6 %), nausea (52.6 %), constipation (42.1 %), diarrhea (42.1 %), fatigue (42.1 %), neutropenia (36.8 %), thrombocytopenia (36.8 %), vomiting (31.6 %), decreased appetite (31.6 %), dehydration (26.3 %), and hypomagnesaemia (26.3 %). In the light of significant hematological and non-hematological toxicity the study was ended before de-escalation of navitoclax. Only one partial response was obtained at any dose tested, thus lowering doses could not have increased efficacy. It is the combination of toxicity with modest efficacy that led to discontinuation. No apparent PK interaction was observed between navitoclax and carboplatin or paclitaxel and the combination of navitoclax and paclitaxel had modest anti-tumor activity. PMID:24894650

  5. INHIBITOR OF THE TRANSCRIPTION FACTOR NF-κB, DHMEQ, ENHANCES THE EFFECT OF PACLITAXEL ON CELLS OF ANAPLASTIC THYROID CARCINOMA IN VITRO AND IN VIVO.

    PubMed

    Pushkarev, V V; Starenki, D V; Pushkarev, V M; Kovzun, O I; Tronko, M D

    2015-01-01

    Anticancer drug paclitaxel (Ptx) effect on biochemical mechanisms, regulating apoptosis in anaplas- tic thyroid carcinoma cells, was studied. It was shown that in addition to apoptotic cell death, Ptx induces signaling cascades that ensure cell survival. Paclitaxel-induced activation of nuclear factor kappa B (NF-κB) leads to an increase of some antiapoptotic proteins expression such as survivin, cIAP, XIAP. A novel NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), was found to enhance cytotoxic effect of Ptx in anaplastic thyroid carcinoma cells. An enhancement of caspase-3 and -9 activation and PARP cleavage as well as the decreased levels of proteins-inhibitors of apoptosis were observed when cells were treated with a combination of both drugs. Mitochondria transmembrane potential (Δψ (m)) loss was observed at higher concentrations of Ptx and DHMEQ. NF-κB inhibition also potentiates paclitaxel effect at tumors formed by xenotransplantation of FRO cells into mice. Tumor mass reduction, significantly different from the effects of each of the compounds alone, was observed in animals, treated with paclitaxel and NF-κB inhibitor. Thus, the combined use of paclitaxel and NF-κB inhibitor inhibits biochemical processes that contribute to the resistance of anaplastic thyroid carcinoma cells to paclitaxel action. PMID:26502701

  6. Therapy effect of either paclitaxel or cyclophosphamide combination treatment in patients with epithelial ovarian cancer and relation to TP53 gene status.

    PubMed Central

    Smith-Sørensen, B.; Kaern, J.; Holm, R.; Dørum, A.; Tropé, C.; Børresen-Dale, A. L.

    1998-01-01

    Cell death after treatment with chemotherapy is exerted by activation of apoptosis, and the p53 protein has been shown to actively participate in this process. This recent focus on TP53 status as a possible determinant of cancer therapy response has raised the question of whether or not mutations in the TP53 gene have an influence on paclitaxel therapy. The TP53 status has been analysed at the DNA level in tumours from 45 ovarian cancer patients randomized to treatment with paclitaxel and cisplatin or cyclophosphamide and cisplatin. Therapy response was obtained for 38 patients with clinically evaluable disease after initial surgery. The positive response rate to the paclitaxel/cisplatin therapy was 85% vs 61% for the patients who received the cyclophosphamide/cisplatin regimen. A significant difference in relapse-free survival in favour of paclitaxel/cisplatin chemotherapy was found (P = 0.001). A total of 33 tumour samples (73%) had detectable sequence alterations in the TP53 gene. When relapse-free survival was estimated for all patients with TP53 alterations in their tumours, a significant better outcome for the paclitaxel/cisplatin group was found compared with the patient group receiving cyclophosphamide and cisplatin therapy (P = 0.002). We did not observe an association between TP53 tumour status and prognosis for patients who received paclitaxel/cisplatin combination treatment, indicating that the effect of this therapy is not influenced by this parameter. PMID:9703286

  7. Enhanced cytotoxicity of TATp-bearing paclitaxel-loaded micelles in vitro and in vivo

    PubMed Central

    Sawant, Rupa R.; Torchilin, Vladimir P.

    2009-01-01

    Cell-penetrating peptide (TATp) was attached to the distal tips of polyethylene glycol (PEG) moieties of polyethyleneglycol-phosphatidylethanolamine (PEG-PE) micelles loaded with paclitaxel (PCT). The TATp-modified micelles demonstrated an increased interaction with cancer cells compared to non-modified micelles resulting in a significant increase of the in vitro cytotoxicity to different cancer cells. TATp-modified PCT-loaded micelles were administered intratumorally in mice and the induction of apoptosis in tumor cells was studied after 48h with the Terminal Deoxynucleotidyl Transferase Biotin-dUTP Nick End Labeling (TUNEL) assay using free PCT and TATp-free PCT-loaded PEG-PE micelles as controls. A significant apoptotic cell death was observed in tumors treated with PCT-loaded micelles modified with TATp, while the treatment with free PCT or with non-modified PCT-loaded micelles resulted in much smaller number of TUNEL-positive cells within tumors. PMID:19446767

  8. Acute and subchronic toxicity analysis of surface modified paclitaxel attached hydroxyapatite and titanium dioxide nanoparticles

    PubMed Central

    Venkatasubbu, Gopinath Devanand; Ramasamy, S; Gaddam, Pramod Reddy; Kumar, J

    2015-01-01

    Nanoparticles are widely used for targeted drug delivery applications. Surface modification with appropriate polymer and ligands is carried out to target the drug to the affected area. Toxicity analysis is carried out to evaluate the safety of the surface modified nanoparticles. In this study, paclitaxel attached, folic acid functionalized, polyethylene glycol modified hydroxyapatite and titanium dioxide nanoparticles were used for targeted drug delivery system. The toxicological behavior of the system was studied in vivo in rats and mice. Acute and subchronic studies were carried out. Biochemical, hematological, and histopathological analysis was also done. There were no significant alterations in the biochemical parameters at a low dosage. There was a small change in alkaline phosphatase (ALP) level at a high dosage. The results indicate a safe toxicological profile. PMID:26491315

  9. Silicate Esters of Paclitaxel and Docetaxel: Synthesis, Hydrophobicity, Hydrolytic Stability, Cytotoxicity, and Prodrug Potential

    PubMed Central

    2015-01-01

    We report here the synthesis and selected properties of various silicate ester derivatives (tetraalkoxysilanes) of the taxanes paclitaxel (PTX) and docetaxel (DTX) [i.e., PTX-OSi(OR)3 and DTX-OSi(OR)3]. Both the hydrophobicity and hydrolytic lability of these silicates can be (independently) controlled by choice of the alkyl group (R). The synthesis, structural characterization, hydrolytic reactivity, and in vitro cytotoxicity against the MDA-MB-231 breast cancer cell line of most of these derivatives are described. We envision that the greater hydrophobicity of these silicates (vis-à-vis PTX or DTX itself) should be advantageous from the perspective of preparation of stable aqueous dispersions of amphiphilic block-copolymer-based nanoparticle formulations. PMID:24564494

  10. Acute and subchronic toxicity analysis of surface modified paclitaxel attached hydroxyapatite and titanium dioxide nanoparticles.

    PubMed

    Venkatasubbu, Gopinath Devanand; Ramasamy, S; Gaddam, Pramod Reddy; Kumar, J

    2015-01-01

    Nanoparticles are widely used for targeted drug delivery applications. Surface modification with appropriate polymer and ligands is carried out to target the drug to the affected area. Toxicity analysis is carried out to evaluate the safety of the surface modified nanoparticles. In this study, paclitaxel attached, folic acid functionalized, polyethylene glycol modified hydroxyapatite and titanium dioxide nanoparticles were used for targeted drug delivery system. The toxicological behavior of the system was studied in vivo in rats and mice. Acute and subchronic studies were carried out. Biochemical, hematological, and histopathological analysis was also done. There were no significant alterations in the biochemical parameters at a low dosage. There was a small change in alkaline phosphatase (ALP) level at a high dosage. The results indicate a safe toxicological profile. PMID:26491315

  11. [Outcome and Problems of Nab-Paclitaxel Therapy for Gastric Cancer in Clinical Practice].

    PubMed

    Doi, Toshifumi; Ishikawa, Takeshi; Okayama, Tetsuya; Dohi, Osamu; Yoshida, Naohisa; Kamada, Kazuhiro; Katada, Kazuhiro; Sogame, Yoshio; Uchiyama, Kazuhiko; Handa, Osamu; Takagi, Tomohisa; Yasuda, Hiroaki; Sakagami, Junichi; Konishi, Hideyuki; Naito, Yuji; Itoh, Yoshito

    2016-02-01

    Nanoparticle albumin-bound paclitaxel(nab-PTX)was approved for the treatment of gastric cancer without a large-scale clinical trial in Japan. Its safety and efficacy should be validated in clinical practice. We retrospectively investigated prognostic factors related to time to treatment failure(TTF)in 11 patients with unresectable or recurrent gastric cancer treated with nab- PTX in our hospital. In univariate analysis, Onodera's prognostic nutritional index(PNI)and the time from the start of first-line chemotherapy to the start of nab-PTX were related to TTF. In multivariate analysis, Onodera's PNI was identified as an independent predictive factor for TTF (hazard ratio 0.056, p=0.022). PNI could contribute to adequate patient selection and the improvement of nab-PTX therapy efficacy ingastric cancer. PMID:27067684

  12. Paclitaxel-loaded phosphonated calixarene nanovesicles as a modular drug delivery platform

    PubMed Central

    Mo, Jingxin; Eggers, Paul K.; Yuan, Zhi-xiang; Raston, Colin L.; Lim, Lee Yong

    2016-01-01

    A modular p-phosphonated calix[4]arene vesicle (PCV) loaded with paclitaxel (PTX) and conjugated with folic acid as a cancer targeting ligand has been prepared using a thin film-sonication method. It has a pH-responsive capacity to trigger the release of the encapsulated PTX payload under mildly acidic conditions. PTX-loaded PCV conjugated with alkyne-modified PEG-folic acid ligands prepared via click ligation (fP-PCVPTX) has enhanced potency against folate receptor (FR)-positive SKOV-3 ovarian tumour cells over FR-negative A549 lung tumour cells. Moreover, fP-PCVPTX is also four times more potent than the non-targeting PCVPTX platform towards SKOV-3 cells. Overall, as a delivery platform the PCVs have the potential to enhance efficacy of anticancer drugs by targeting a chemotherapeutic payload specifically to tumours and triggering the release of the encapsulated drug in the vicinity of cancer cells. PMID:27009430

  13. Enhanced combination therapy effect on paclitaxel-resistant carcinoma by chloroquine co-delivery via liposomes

    PubMed Central

    Gao, Menghua; Xu, Yuzhen; Qiu, Liyan

    2015-01-01

    A novel composite liposomal system co-encapsulating paclitaxel (PTX) with chloroquine phosphate (CQ) was designed for treating PTX-resistant carcinoma. It was confirmed that liposomal CQ can sensitize PTX by means of autophagy inhibition and competitively binding with multidrug-resistance transporters. Furthermore, according to the in vitro cytotoxicity and apoptosis assay, real-time observation of cellular uptake, and in vivo tissue distribution study, co-encapsulation of PTX and CQ in liposomes was validated as superior to the mixture of PTX liposome plus CQ liposome due to the simultaneous delivery and synergetic effect of the two drugs. Consequently, this composite liposome achieved significantly stronger anticancer efficacy in vivo than the PTX liposome plus CQ liposome mixture. This study helps to guide and enlighten ongoing and future clinical trials about the optimal administration modes for drug combination therapy. PMID:26543365

  14. Paclitaxel-loaded micelles enhance transvascular permeability and retention of nanomedicines in tumors.

    PubMed

    Danhier, Fabienne; Danhier, Pierre; De Saedeleer, Christophe J; Fruytier, Anne-Catherine; Schleich, Nathalie; des Rieux, Anne; Sonveaux, Pierre; Gallez, Bernard; Préat, Véronique

    2015-02-20

    Paclitaxel (PTX)-loaded polymeric micelles (M-PTX) have been shown to enhance the blood flow and oxygenation of tumors 24h after treatment. We hypothesized that these changes in the tumor microenvironment could lead to an enhancement of the EPR (enhanced permeability and retention) effect. M-PTX, administered 24h before analysis, increased the accumulation of macromolecules, nanoparticles and polymeric micelles in tumors. This increased EPR effect could be linked to normalization of the tumor vasculature and decreased interstitial fluid pressure. M-PTX used as a pre-treatment allowed a more effective delivery of three nanomedicines into tumors: polymeric micelles, liposomes and nanoparticles. These experiments demonstrate an enhanced EPR effect after M-PTX treatment, which lead to better availability and enhanced efficacy of a subsequent treatment with nanomedicines. PMID:25578367

  15. Paclitaxel-loaded phosphonated calixarene nanovesicles as a modular drug delivery platform.

    PubMed

    Mo, Jingxin; Eggers, Paul K; Yuan, Zhi-Xiang; Raston, Colin L; Lim, Lee Yong

    2016-01-01

    A modular p-phosphonated calix[4]arene vesicle (PCV) loaded with paclitaxel (PTX) and conjugated with folic acid as a cancer targeting ligand has been prepared using a thin film-sonication method. It has a pH-responsive capacity to trigger the release of the encapsulated PTX payload under mildly acidic conditions. PTX-loaded PCV conjugated with alkyne-modified PEG-folic acid ligands prepared via click ligation (fP-PCVPTX) has enhanced potency against folate receptor (FR)-positive SKOV-3 ovarian tumour cells over FR-negative A549 lung tumour cells. Moreover, fP-PCVPTX is also four times more potent than the non-targeting PCVPTX platform towards SKOV-3 cells. Overall, as a delivery platform the PCVs have the potential to enhance efficacy of anticancer drugs by targeting a chemotherapeutic payload specifically to tumours and triggering the release of the encapsulated drug in the vicinity of cancer cells. PMID:27009430

  16. Cellular Uptake Mechanism of Paclitaxel Nanocrystals Determined by Confocal Imaging and Kinetic Measurement.

    PubMed

    Chen, Yan; Li, Tonglei

    2015-09-01

    Nanocrystal formulation has become a viable solution for delivering poorly soluble drugs including chemotherapeutic agents. The purpose of this study was to examine cellular uptake of paclitaxel nanocrystals by confocal imaging and concentration measurement. It was found that drug nanocrystals could be internalized by KB cells at much higher concentrations than a conventional, solubilized formulation. The imaging and quantitative results suggest that nanocrystals could be directly taken up by cells as solid particles, likely via endocytosis. Moreover, it was found that polymer treatment to drug nanocrystals, such as surface coating and lattice entrapment, significantly influenced the cellular uptake. While drug molecules are in the most stable physical state, nanocrystals of a poorly soluble drug are capable of achieving concentrated intracellular presence enabling needed therapeutic effects. PMID:26104805

  17. Fabrication of poly hydroxybutyrate-polyethylene glycol-folic acid nanoparticles loaded by Paclitaxel.

    PubMed

    Rezaei, Fatemeh; Rafienia, Mohammad; Keshvari, Hamid; Sattary, Mansooreh; Naeimi, Mitra; Keyvani, Hossein

    2016-01-01

    In this study drug (paclitaxel)-loaded nanoparticles of poly hydroxybutyrate-polyethylene glycol-folic acid (PHB-PEG-FOL) were prepared by using an oil-in-water (O/W) emulsion-solvent evaporation method. The functionalization and conjugation steps in the chemical synthesis were confirmed using Fourier transform infrared (FTIR) and nuclear magnetic resonance tests ((1)H NMR). Morphology of nanoparticles was evaluated by scanning electron microscopy (SEM). Nanoparticles were characterized by particle size analyzer. Between two samples containing drug, the lower doses showed more homogeneous distribution, and the lowest aggregation. The drug release profiles showed a two-phase release including initial rapid release and a continuous release. MG63 cells were used to evaluate cytotoxicity. The cytotoxicity of PHB-PEG-FOL nanoparticles with drug against cancer cells was much higher and longer than free drug sample. These nanoparticles were successfully synthesized as a novel system for targeted drug delivery against cancer cells. PMID:26234551

  18. PLGA nanoparticles codeliver paclitaxel and Stat3 siRNA to overcome cellular resistance in lung cancer cells

    PubMed Central

    Su, Wen-Pin; Cheng, Fong-Yu; Shieh, Dar-Bin; Yeh, Chen-Sheng; Su, Wu-Chou

    2012-01-01

    Background: Effective cancer chemotherapy remains an important issue in cancer treatment, and signal transducer and activator of transcription-3 (Stat3) activation leads to cellular resistance of anticancer agents. Polymers are ideal vectors to carry both chemotherapeutics and small interfering ribonucleic acid (siRNA) to enhance antitumor efficacy. In this paper, poly(lactic-co-glycolic acid) (PLGA) nanoparticles loaded with paclitaxel and Stat3 siRNA were successfully synthesized, and their applications in cancer cells were investigated. Methods: Firstly, paclitaxel was enclosed by PLGA nanoparticles through solvent evaporation. They were then coated with cationic polyethylenimine polymer (PLGA-PEI-TAX), enabling it to carry Stat3 siRNA on its surface through electrostatic interactions (PLGA-PEI-TAX-S3SI). The size, zeta potential, deliver efficacy, and release profile of the PLGA nanocomplexes were characterized in vitro. The cellular uptake, intracellular nanoparticle trajectory, and subsequent cellular events were evaluated after treatment with various PLGA nanocomplexes in human lung cancer A549 cells and A549-derived paclitaxel-resistant A549/T12 cell lines with α-tubulin mutation. Results: A549 and A549/T12 cells contain constitutively activated Stat3, and silencing Stat3 by siRNA made both cancer cells more sensitive to paclitaxel. Therefore, PLGA-PEI-TAX-S3SI was synthesized to test its therapeutic role in A549 and A549/T12 cells. Transmission electron microscopy showed the size of PLGA-PEI-TAX-S3SI to be around 250 nm. PLGA-PEI nanoparticles were nontoxic. PLGA-PEI-TAX was taken up by A549 and A549/T12 cells more than free paclitaxel, and they induced more condensed microtubule bundles and had higher cytotoxicity in these cancer cells. Moreover, the yellowish fluorescence observed in the cytoplasm of the cancer cells indicates that the PLGA-PEI nanoparticles were still simultaneously delivering Oregon Green paclitaxel and cyanine-5-labeled Stat3 siRNA 3 hours after treatment. Furthermore, after the cancer cells were incubated with the synthesized PLGA nanocomplexes, PLGA-PEI-TAX-S3SI suppressed Stat3 expression and induced more cellular apoptosis in A549 and A549/T12 cells compared with PLGA-PEI-TAX. Conclusion: The PLGA-PEI-TAX-S3SI complex provides a new therapeutic strategy to control cancer cell growth. PMID:22904633

  19. Aptamer conjugated paclitaxel and magnetic fluid loaded fluorescently tagged PLGA nanoparticles for targeted cancer therapy

    NASA Astrophysics Data System (ADS)

    Aravind, Athulya; Nair, Remya; Raveendran, Sreejith; Veeranarayanan, Srivani; Nagaoka, Yutaka; Fukuda, Takahiro; Hasumura, Takahashi; Morimoto, Hisao; Yoshida, Yasuhiko; Maekawa, Toru; Sakthi Kumar, D.

    2013-10-01

    Controlled and targeted drug delivery is an essential criterion in cancer therapy to reduce the side effects caused by non-specific drug release and toxicity. Targeted chemotherapy, sustained drug release and optical imaging have been achieved using a multifunctional nanocarrier constructed from poly (D, L-lactide-co-glycolide) nanoparticles (PLGA NPs), an anticancer drug paclitaxel (PTX), a fluorescent dye Nile red (NR), magnetic fluid (MF) and aptamers (Apt, AS1411, anti-nucleolin aptamer). The magnetic fluid and paclitaxel loaded fluorescently labeled PLGA NPs (MF-PTX-NR-PLGA NPs) were synthesized by a single-emulsion technique/solvent evaporation method using a chemical cross linker bis (sulfosuccinimidyl) suberate (BS3) to enable binding of aptamer on to the surface of the nanoparticles. Targeting aptamers were then introduced to the particles through the reaction with the cross linker to target the nucleolin receptors over expressed on the cancer cell surface. Specific binding and uptake of the aptamer conjugated magnetic fluid loaded fluorescently tagged PLGA NPs (Apt-MF-NR-PLGA NPs) to the target cancer cells induced by aptamers was observed using confocal microscopy. Cytotoxicity assay conducted in two cell lines (L929 and MCF-7) confirmed that targeted MCF-7 cancer cells were killed while control cells were unharmed. In addition, aptamer mediated delivery resulting in enhanced binding and uptake to the target cancer cells exhibited increased therapeutic effect of the drug. Moreover, these aptamer conjugated magnetic polymer vehicles apart from actively transporting drugs into specifically targeted tumor regions can also be used to induce hyperthermia or for facilitating magnetic guiding of particles to the tumor regions.

  20. Role of microRNAs in the resistance of prostate cancer to docetaxel and paclitaxel

    PubMed Central

    2016-01-01

    Taxanes, a group of cancer drugs that includes docetaxel and paclitaxel, have become a front-line therapy for a variety of metastatic cancers, but resistance can develop. There are several docetaxel resistance mechanisms in prostate cancer: unfavorable tumor microenvironment, drug efflux pump, alterations in microtubule structure and/or function, and apoptotic defects (e.g. up regulation of Bcl-2 and clusterin or activation of the PTEN/PI3K/mTOR pathway or activation of the MAPK/ERK pathway). MicroRNAs (miRNAs), small regulatory molecules, could also function as a contributor to the resistance of cancer cells to commonly used anti-cancer drugs. Aberrant expressions of miRNAs that can act as tumor suppressors or oncogenes are closely associated with the development, invasion and metastasis of various cancers including prostate cancer. Nearly 50 miRNAs have been reported to be differentially expressed in human prostate cancer so far, but knowledge concerning the effects of miRNAs on the sensitivity to anti-cancer drugs is still limited. The author of the review focus on probable impact of miRNAs on the resistance to docetaxel and paclitaxel. Overexpression of miR-21 increased the resistance of prostate cancer cells to docetaxel by targeting PDCD4, PTEN, RECK, and BTG2. Nevertheless, decreased expressions of tumor suppressors: miR-34a, miR-143, miR-148a and miR-200 family are involved in resistance of anti-cancer drugs by inhibition of apoptosis and activation of signaling pathways. Conclude miRNAs become very attractive target for potential therapeutic interventions. PMID:26843836