Project description:Docetaxel is the standard first line therapy for hormone-refractory prostate cancer patients. Here we generated models of Docetaxel resistance in prostate cancer cells to study the molecular pathways that drive the acquisition of resistance to this therapy. We used microarrays to detail the global program of gene expression underlying the acquisition of Docetaxel resistance in prostate cancer cells. Parental Docetaxel-sensitive prostate cancer cell lines (DU145 and 22Rv1) and selected Docetaxel-resistant cells (DU145-DR and 22Rv1-DR) were harvested for RNA extraction and hybridization on Affymetrix microarrays. Samples were analyzed in triplicates in order to increase the resolution of expression profiles.
Project description:Docetaxel-based chemotherapy is the standard first-line therapy in metastatic castration-resistant prostate cancer. However, most patients eventually develop resistance to this treatment. The aim of the study was to identify key molecular genes and networks associated with docetaxel resistance in 2 models of docetaxel-resistant castration-resistant prostate cancer cell lines. DU-145 and PC-3 cells were converted to docetaxel-resistant cells, DU-145R and PC-3R, respectively. Whole-genome arrays were used to compare global gene expression between these 4 cell lines. Arrays were performed by triplicate for each cell line.
Project description:The purpose of this study was to identify molecular markers of pathologic response to neoadjuvant dose-dense docetaxel treatment using gene expression profiling on pretreatment biopsies. Patients with high-risk, operable breast cancer were treated with 75 mg/m2 IV of docetaxel on day 1 of each cycle every 2 weeks x 4 cycles . Tumor tissue from pretreatment biopsies was obtained from 12 patients enrolled in the study. Gene expression profiling were done on serial sections of the biopsies from patients that achieved a pathologic complete response (pCR) and compared to those with residual disease, non-pCR (NR). Tumor tissues from pretreatment needle biopsies from patients enrolled in a dose-dense docetaxel clinical trial were laser capture microdissected for RNA extraction and hybridization to Affymetrix microarrays. We analyzed one array (sample A) from duplicate samples from each patient.
Project description:Low topo2a expression and ER-negative status were predictors of response to doxorubicin, while small tumor size and ER-negative status predicted response to docetaxel. Docetaxel was superior to doxorubicin in triple-negative/basal-like tumors, while no significant differences between these drugs were seen in the remaining intrinsic subtypes Keywords: reference x sample
Project description:Purpose: To determine whether docetaxel therapy of advanced prostate cancer can be improved by using docetaxel in combination with Aneustat (OMN54), a multivalent botanical drug candidate undergoing a Phase-I Clinical Trial, and to identify the molecular action of this drug combination. Experimental Design: Human metastatic, androgen-independent C4-2 prostate cancer cells and NOD-SCID mice bearing PTEN-deficient, metastatic and PSA-secreting, patient-derived subrenal capsule LTL-313H prostate cancer tissue xenografts were treated with docetaxel and Aneustat, either alone or in combination. Culture growth (at 48 hours) and xenograft size (at 3 weeks) were determined and animal health monitored. Xenografts were gene expression profiled using gene expression microarrays. Androgen receptor (AR) expression and AKT phosphorylation were examined. Results: Aneustat markedly inhibited C4-2 cell replication in a dose-dependent manner in vitro, reducing AR expression and AKT phosphorylation. Aneustat was not as effective as docetaxel in inhibiting LTL-313H xenograft growth. When combined, Aneustat and docetaxel markedly and synergistically enhanced anti-tumor activity without inducing major host toxicity, even leading to complete growth inhibition and tumor shrinkage not obtained with the single drugs. AR expression and AKT signalling in the xenografts were inhibited by docetaxel+Aneustat, but not by the single agents. Expression microarray analysis indicated that docetaxel+Aneustat led to expanded anticancer activity, in particular to targeting of cancer hallmarks that were not affected by the drugs on their own. Conclusion: Our findings, obtained with a clinically relevant prostate cancer model, suggest, for the first time, that docetaxel-based therapy of advanced human prostate cancer may be improved by combining docetaxel with Aneustat.
Project description:Low topo2a expression and ER-negative status were predictors of response to doxorubicin, while small tumor size and ER-negative status predicted response to docetaxel. Docetaxel was superior to doxorubicin in triple-negative/basal-like tumors, while no significant differences between these drugs were seen in the remaining intrinsic subtypes Keywords: reference x sample reference x sample
Project description:Upregulation of the glucocorticoid receptor (GR) has been identified as a possible bypass mechanism in CRPC. Recently, it has been demonstrated that the combination of docetaxel with mifepristone (D+M), an inhibitor of the GR, reinduces sensitivity to docetaxel in docetaxel resistant cell models. This study was designed to uncover and characterize molecular mechanisms responsible for this observation.
Project description:This phase I/II neoadjuvant trial determined maximally-tolerated doses (MTD), dose-limiting toxicities (DLT), response-to-therapy, and explored the role of new response biomarkers. The combination regimens were delivered with acceptable toxicity, good clinical response, inducing changes in tumor RNA content and integrity. Pre-treatment gene expressions impacted clinical response, including several near 17q12, which with ERBB2, may better identify chemoresponsiveness. The NCIC Clinical Trials Group MA.22 phase I/II clinical trial (ClinicalTrials.gov identifier NCT00066443) sought to determine the optimal dosing regimens for docetaxel/epirubicin combination chemotherapy in women with locally advanced (over 95% of patients) or inflammatory breast cancer. The protocol was approved by Health Canada and local Ethics Review Boards, and patients provided written, informed consent. Various doses of epirubicin and docetaxel were administered to patients in either a standard q3 weekly (Schedule A) or dose dense q2 weekly (Schedule B) regimen. Doses for Schedule A were 75 mg/m2 IV of docetaxel and 75, 90, 105, or 120 mg/m2 IV of epirubicin (with 6 mg of pegfilgrastim per cycle on day 2 to prevent neutropenia). Doses for both docetaxel and epirubicin in Schedule B were 50, 60, and 70 mg/m2 IV (with identical pegfilgrastim support). For each schedule, phase I was dose finding for phase II. Patients were allocated to the various phases and dosing regimens of the trial without randomization. None of the patients received trastuzumab in the initial years of the study and HER2+ patients were not enrolled on study, once trastuzumab funding became available. Six tumor biopsy cores were obtained pre-, mid-, and post-treatment: 3 cores for pathologic assessment; 3 cores for microarray studies. Total RNA was isolated from these cores and RNA integrity was assessed using Agilent Bioanalyzer. One of the RNA samples with the best quality was used for microarray study. One colour microarray of Agilent whole human genome nucleotide arrays was conducted with one array per patient. The current data set represents pre-treatment set. MA.22 clinical trial accrued T3N0, any N2 or N3, and T4 breast cancer patients (according to the classification described at; http://emedicine.medscape.com/article/2007112-overview). However, since the current study does not focus on the tumor grade/stage, the information was not provided in the current records.
Project description:Docetaxel is the standard first line therapy for hormone-refractory prostate cancer patients. Here we generated models of Docetaxel resistance in prostate cancer cells to study the molecular pathways that drive the acquisition of resistance to this therapy. We used microarrays to detail the global program of gene expression underlying the acquisition of Docetaxel resistance in prostate cancer cells.