ENHANCEMENT OF 5-FLUOROURACIL CYTOTOXICITY BY CISPLATIN IN BRAIN-TUMOR CELL-LINES

Cisplatin reportedly plays an important role as a chemical modulator i n enhancing the chemotherapeutic effects of 5-fluorouracil on tumour c ells. The aim of the present study was to test the synergistic cytotox icity of cisplatin and 5-fluorouracil in 5-fluorouracil-resistant (C6) and -sensitive (9L) rat brain tumour cell lines. Survival fractions, determined using colony-formation assays, were compared following 5-fl uorouracil treatment, with and without cisplatin. The presence of cisp latin (1-10 mu M) enhanced cytotoxicity by more than three times compa red with 5-fluorouracil alone in 5-fluorouracil-resistant C6 cells, wh ereas no enhancement effects were noted in 9L cells. These results sug gest that a cisplatin-fluorouracil-based regimen may be promising in t he treatment of 5-fluorouracil-resistant brain tumours. (C) 1996 Acade mic Press Limited