ENHANCEMENT OF ANTITUMOR EFFECTS OF NEW ANALOG OF PLATINUM, CIS-DIAMMINE(GLYCOLATO) PLATINUM (254-S) COMBINED WITH HYPERTHERMIA IN-VIVO

Cis-diammine (glycolato) platinum (254-S) is a second generation plati num complex with reduced nephrotoxicity. In this study the antitumor e ffect of 254-S combined with hyperthermia in vivo in mice was studied. On the 6th day after inoculation of the Ehrlich ascites tumour cells, 254-S (15mg/kg) was administered intraperitoneally (i.p.) and hyperth ermia was induced by using a circulating water bath at 42.5 degrees C for 45min. The antitumour effect was evaluated by relative tumour volu me. Furthermore, platinum concentration in tumour tissue was determine d by using atomic absorption spectrophotometry. The most effective con dition was found to be the combination of 254-S with hyperthermia. A s ignificantly higher concentration of platinum in the tumour tissue was observed when treatment with 254-S was combined with hyperthermia, th an with treatment using 254-S alone. Our study suggested that the accu mulation of 254-S in the tumour tissue, and its retention at a high co ncentration within the tumour tissue long term was one of the reasons for the enchancement of antitumour effect of 254-S treatment when comb ined with hyperthermia.