The effect of cytostatics and hyperthermia on RAJI human lymphoma cells

To evaluate the effect of hyperthermia on cytostatic activity of chemotherapeutic drugs carboplatin, cisplatin, oxaliplatin, carmustine, gemcitabine and etoposide in human lymphoma cell culture. RAJI human lymphoma cells were incubated with cytostatics at 37 °C or 42 °C and evaluated for cell culture growth. The number of viable cells after incubation with the drugs (except for gemcitabine) at 42 °C for 30 min was significantly lower than at 37 °C. There were synergism of cytostatic effects of platinum drugs (carboplatin, cisplatin and oxaliplatin) with cytostatic effect of 42 °C and the summation of cytostatic effect of carmustine or etoposide with the action of hyperthermia. The thermal enhancement ratio was 3.0 for oxaliplatin, 2.0 for cisplatin, 1.8-2.4 for carboplatin. The combination of platinum drugs with gemcitabine resulted in a significant enhancement of cytostatic activity. Our findings suggest that a gain in sensitivity of RAJI human lymphoma cells to platinum drugs occurs at 42 °C.