Aim: To determine if the drug doses and administration schedules of carboplatin and gemcitabine combination affect antitumor effects.
Materials and methods: The inhibition of cell viability was measured by MTT assay. Median effect analysis was conducted to determine the cytotoxicity activity of carboplatin and gemcitabine combination. Cell cycle changes were analyzed by flow cytometry.
Results: Synergism was observed when the bladder cancer cell line 5637 cells were treated with gemcitabine followed by carboplatin or concurrent carboplatin/gemcitabine. In contrast, moderate antagonism was observed when cells were treated with carboplatin followed by gemcitabine. Cell cycle analysis showed that the combined effect of these two drugs was cell cycle disturbance.
Conclusion: Different doses and administration schedules affect the antitumor effect of carboplatin/gemcitabine combination that may have clinical significance in the treatment for bladder cancer.