Many tumor cells become resistant to commonly used cytotoxic drugs due to the overexpression of ATP-binding cassette (ABC) transporters. Specifically, p-glycoprotein (MDR-1) is frequently up-regulated in chemotherapy-resistant tumor cells, which is associated with poor prognosis. On the other hand, human leukocyte antigen (HLA) class I molecules are known to be significantly down-regulated in advanced tumor cells to escape from immune surveillance. However, the relationship between MDR-1 expression and HLA expression is not fully understood. Recently, we have developed a recombinant single-chain Fv diabody specific to HLA-A and demonstrated that this agent mediates cell death in HLA-overexpressing lymphoid tumor cells but not in normal cells (
Disclosure: No relevant conflicts of interest to declare.