COMBINATION CYTOTOXIC EFFECTS OF 5-FLUOROURACIL AND CARBOPLATIN AGAINST HUMAN LUNG-CANCER CELL-LINES

Cisplatin have been shown to enhance cytotoxicity of 5-fluorouracil ag ainst human neoplasms by increasing intracellular reduced folate conce ntrations. We conducted an in vitro study to investigate the cytotoxic activities of combination of carboplatin, an analogue of cisplatin an d 5-fluorouracil against human lung cancer cell lines. Methylthiazol t etrazolium bromide (MTT) assay was used to test the drug combinations. We found the carboplatin enhanced the cytotoxicity of 5-fluorouracil and prior treatment of 5-fluorouracil and posterior treatment of carbo platin produced a significant cytotoxic effects. The sequence of these drugs at clinically relevant concentrations was synergistic for these cell lines. Our in vitro results provide a rationale for clinical stu dies of the sequential combination of these drugs.