Cancer cells acquire resistance to anticancer drugs: An update

The efficacy of cancer chemotherapy is often affected by the emergence of resistant can-cer cells. While biochemical and pharmaco-logical mechanisms have been proposed to ex-plain chemo-resistance, the genes involved in this process have not been fully identified. We previ-ously used genomic DNA microarrays and quantitative RT-PCR to identify the genes associ-ated with resistance to chemotherapeutic drugs, particularly to the genotoxic agent cispla-tin. Notably, knockdown of the cisplatin resistance (CPR) genes that we identified was shown to reduce chemoresistance and to suppress the growth of tumor xenographs in cispla-tin-treated mice, indicating that the newly identified CPR genes may represent potential ther-apy candidates to limit chemo-resistance and to improve the efficacy of anticancer drugs. In addi-tion to genetic mutations, re-searchers have found that epigenetic changes and alternative splic-ing of specific genes may also allow cancer cells to become resistant to chemotherapeu-tic drugs. In this article, the au-thors present an overview of the latest findings in this field, includ-ing genetic changes, epige-netic changes and alternative splicing.