Detection of the Multidrug Resistance Phenotype in Leukemic Cells with an In Vitro Chemosensitivity Assay

Detection of the pattern of resistance of tumor cells to chemotherapeutic agents is an important task in the treatment of patients with malignant diseases. In our laboratory, we established and optimized an in vitro chemosensitivity assay based on the incorporation of radioactively labeled nucleotides in the presence of various drugs. Using this assay, we analyzed the pattern of resistance in 62 patients with leukemia.