5-FLUOROURACIL PLUS CISPLATIN PLUS MITOMYCIN-C IS A RELATIVELY MOST EFFECTIVE COMBINATION AGAINST XENOGRAFT LINES OF HUMAN COLORECTAL-CANCER

5-Fluorouracil (5-FU) has been an accepted effective against colorecta l cancer, but combination regimens resulted in a lesser effect than 5- FU alone. The present study was designed to evaluate the efficiency of various combination chemotherapies, including 5-FU, on human colorect al cancer xenograft lines (CC-KK and RC-TK), which had been passed by transplantation in nude mice. Eight anticancer agents [5-FU, mitomycin C (MMC), adriamycin (ADR), 4'-epirubicin (EPIR), carboquone (CQ), cis platin, carboplatin and etoposide (VP-16)] and their combinations were evaluated at 2-4 times the clinical dose. When the agents were admini stered singly, 5-FU, EPIR and CQ were effective against CC-KK, and 5-F U, MMC, EPIR, ADR, CQ and carboplatin were effective against RC-TK. Of the two-agent combinations including 5-FU, cisplatin+5-fU was the mos t effective against both CC-KK and RC-TK. However, of the three-agent combinations, only cisplatin+5-FU+MMC was more effective against both lines than cisplatin+5-FU. These results suggest that cisplatin+5-FU+M MC may be the most useful regimen against colorectal cancers in clinic al application.