Hrubá Lenka RNDr., Ph.D.

Mechanism of multidrug resistance (MDR) in cancer cells

Drug resistance is one of the major challenges cancer therapy is facing to. Every year, cancer affects millions of people around the world. More than 19 million new cases were diagnosed worldwide in 2020. According to the National Cancer Registry (NOR), there were 67,000 new cases in the Czech Republic, and there were 27,468 deaths associated with cancer diagnosis. More than 10 million patients died worldwide. There can be many reasons for the treatment failure- from late diagnosis of the disease, to limited surgical or radiotherapy options, to drug resistance that greatly reduce the choice of suitable chemotherapeutics. In order to simulate the situation that takes place in the body of a patient treated with substances with cytostatic or cytotoxic effect, it is necessary to choose the right biological model. One of the suitable models seems to be tumor cell lines, which can be used for selection of clones with a resistant phenotype. These cells can be then tested in in vitro and in vivo conditions. In resistant cell lines it is possible to describe the mechanism of drug resistance and open the way for new potential therapies, to verify the sensitivity of resistant tumors to newly developed cytostatics, or to predict how easily and whether resistance to a particular drug will arise at all.