TY - JOUR T1 - Biomarkers for Sensitivity to Docetaxel and Paclitaxel in Human Tumor Cell Lines <em>In Vitro</em> JF - Cancer Genomics - Proteomics JO - Cancer Genomics Proteomics SP - 219 LP - 226 VL - 2 IS - 4 AU - ELZBIETA IZBICKA AU - DAVID CAMPOS AU - GILBERT CARRIZALES AU - ANTHONY TOLCHER Y1 - 2005/07/01 UR - http://cgp.iiarjournals.org/content/2/4/219.abstract N2 - Background: Paclitaxel and docetaxel affect microtubule polymerization, yet surprising differences in tumor sensitivity to the taxanes have been observed. Docetaxel was superior to paclitaxel in inhibiting in vivo growth of human lung and prostate but not breast cancer models. Materials and Methods: We compared drug cytotoxicity, effects on β-tubulin isoforms, markers of apoptosis and proteomic profiles in human prostate (LNCaP), lung (SK-MES, MV-522) and breast (MCF-7, MDA-231) cancer cell lines in vitro. Results: Cytotoxicity followed the order SK-MES&lt;MV-522&lt;LNCaP&lt;MCF-7&lt;MDA-MB-231; docetaxel was more effective. Cytotoxicity directly correlated with Bcl-2 expression in vitro and inversely correlated with docetaxel sensitivity in vivo. Proteomic profiling identified a protein expressed in lung and prostate cells, which was differentially regulated by docetaxel and paclitaxel in SK-MES. Conclusion: The superior activity of docetaxel in tumors with low Bcl-2 warrants further studies on biomarkers for drug sensitivity and investigation of docetaxel in combination with drugs that reduce Bcl-2 gene expression. ER -