Telomerase Activity and Telomere Length in Human Tumor Cells with Acquired Resistance to Anticancer Agents

AbstractTelomeres and telomerase are targets for anticancer drug development and specific inhibitors are currently under clinical investigation. However, it has been reported that standard cytotoxic agents can affect telomere length and telomerase activity suggesting that they also have of a role in drug resistance. In this study, telomere lengths and telomerase activity as well as drug efflux pump expression, glutathione (GSH) levels and polyadenosine-ribose polymerase (PARP) cleavage were assessed in a panel of human tumor cell lines made resistant to vindesine, gemcitabine and cisplatin. These included two lung cancer cell lines resistant to vindesine (LXFL 529L/Vind, LXFA526L/Vind), a renal cancer cell line (RXF944L/Gem) and an ovarian cancer cell line(AG6000) resistant to gemcitabine, and one resistant to cisplatin (ADDP). The resistant clones were compared to their parental lines and evaluated for cross resistance too there cytotoxic agents. Several drug specific resistance patterns were found, and ...