Enhanced antitumor efficacy of nedaplatin with 5-fluorouracil against human squamous carcinoma xenografts

Background: The antitumor efficacy of a combination of Nedaplatin (NDP) with 5-fluorouracil (5-FU) was evaluated using human squamous carcinomas in vivo. Because NDP was developed as a second generation platinum complex, we also compared the antitumor activity of NDP with 5-FU with that of Cisplatin (CDDP) with 5-FU. Materials and Methods: 5-FU was injected daily for five days and either NDP or CDDP was injected once via the tail vein of mice implanted with KB3-1, OCC-1-JCK, LJC-1-JCK and Ma44 human squamous carcinomas. In some experiments continous administration of 5-FU using an osmotic pump was utilized. Results: The sequential administration of 5-FU prior to NDP ol CDDP (FN or FC therapy) resulted in enhanced inhibition of tumor growth in comparison with NDP, CDDP or 5-FU monotherapy against KB3-1, OCC-1-JCK and LJC-1-JCK squamous carcinomas. The combination of FN treatment was synergistic and as effective as that of FC treatment. FN treatment with continuous infusion Of 5-FU using an osmotic pump, also led to enhanced tumor growth inhibition and prolonged survival against Ma44 squamous carcinoma. Conclusion: The results demonstrated the antitumor efficacy NDP with 5-FU against four human squamous carcinoma xenografts and suggested the clinical effectiveness of FN treatment.