Novel siRNA-Based Approach to Study Mechanisms of Resistance/Action of a New Drug in Treatment of Breast Cancer. Addendum

摘要

The mechanism by which ET-743 (YondelisTM, trabectedin) exerts its antitumor activity is not understood. The goal of this study was to study the mechanism of action/resistance of ET-743 in breast cancer cells using a novel siRNA-based approach. Two primers representing the sense and anti-sense DNA template of the random siRNA inserts were cloned into the linearized pFIV-H1/U6 siRNA expression vector. Out of 33 siRNA sequences obtained from vector transformed E.coli colonies, predicted that 67% of the siRNA template sequences would generate functional siRNA sequences and that 82% of the functional siRNA sequences were random. A pool of plasmids encoding the random siRNAs (with a possible 105 to 106different siRNAs), either transduced with pseudo- lentiviral particles or transfected with electroporation, were tested in the MCF-7 breast cancer cell line. The cell line was then treated with a lethal dose of ET-743 and cytarabine, however no resistant colonies were obtained. Further scaling-up is required to fufill the goals of this project.