Simotaxel

Multidrug resistance (MDR) represents a major hindrance to the efficacy of cancer chemotherapeutics. While surgical resection, radiation, and chemotherapy can be used to reduce tumor size, the subsequent appearance of drug resistant cells is a frequent problem. One of the main contributors to the development of MDR is increased expression of multi-drug resistant protein 1 (MDR1), also known as P-glycoprotein (P-gp). P-gp is a membrane-associated efflux pump that can efficiently remove internalized taxane-base chemotherapeutics thus preventing drug accumulation and maintaining cellular viability. Consequently, investigation into the molecular mechanisms responsible for regulation of P-gp expression is necessary to facilitate treatment of MDR tumors. Using molecular and biochemical approaches, we identified that the micro-RNA, miRNA149, contributes to the development of MDR within malignant mesothelioma cells by regulating the expression of MDR1.

Purpose: To compare clinical outcomes of metastatic head and neck cancer patients treated in phase I clinical trials with clinical outcomes of those patients who had their last Food and Drug Administration (FDA)–approved therapy in the setting of metastatic disease.Experimental Design: We retrospectively reviewed the outcomes of 61 consecutive patients with head and neck tumors treated in 36 phase I trials at The University of Texas M.D. Anderson Cancer Center between July 2004 and September 2009.Results: The most common histology was head and neck squamous cell carcinoma (62%). Median age was 55 years (range, 26-80). Eastern Cooperative Oncology Group performance status was 0 to 1 for 95% of patients. Fifty-nine patients had received FDA-approved drugs as the backbone of their last systemic therapy before inclusion in phase I trials (median, 2 systemic therapies). Progression-free survival (PFS) on phase I trials was not inferior to PFS on their last FDA-approved therapies (12 versus 10.7 weeks, log-rank P = 0.87). Fifty-three patients were evaluable for response by Response Evaluation Criteria in Solid Tumors criteria. Four (7%) had partial responses and 16 (26%) had stable disease for ≥4 months. In univariate analysis, number of metastatic sites, lactate dehydrogenase (LDH) levels at baseline, and Royal Marsden Hospital prognosis scores were significant predictors of survival. Only LDH was significant in multivariate analysis (hazard ratio, 6.35; P ≤ 0.0001).Conclusions: For patients with heavily pretreated advanced head and neck tumors, PFS on phase I trials is not inferior to PFS with their last FDA-approved therapy. The only significant predictor of survival in the multivariate analysis was baseline LDH. Clin Cancer Res; 16(15); 4031–7. ©2010 AACR.