Proteomics for studying cancer cells and the development of chemoresistance.

Extensive studies during the last decades have identified several mechanisms through which cells escape the cytotoxic effects of a variety of chemotherapeutic drugs. One type of drug resistance is called multidrug resistance (MDR), because selection with one anticancer drug leads to cross-resistance with a wide range of other drugs. These MDR cells express frequently plasma transport proteins like p-glycoprotein. But cellular resistance to chemotherapy is multifactorial and may be affected by the cell cycle stage and proliferation status, biochemical mechanisms such as detoxification, cellular drug transport, or DNA replication and repair mechanisms. Several laboratory techniques, such as polymerase chain reaction, immunocytochemistry, flow cytometry, blotting, and fluorescent microscopy have been used for the identification of MDR markers and mechanisms. We review the possibilities in studying cancer biology and development of chemoresistance in cancer treatment using the proteomic approach.