Independent antitumor spectrum of UCN-01 (7-hydroxystaurosporine) against gastric and colorectal cancers as detected by MTT assay

To evaluate the clinical usefulness of 7-hydroxystaurosporine (UCN-01), we compared the antitumor spectrum of UCN-01 with those of conventional antitumor agents against 40 fresh gastric and 40 fresh colorectal cancer specimens using the MTT assay. At a cut-off concentration of 30 μg/ml, UCN-01 showed a higher efficacy rate than mitomycin C (MMC), cisplatin, and 5-fluorouracil (5-FU) against both gastric and colorectal cancers. With respect to the gastric cancer specimens, the antitumor spectrum of UCN-01 was independent from those of the other agents, while the patterns of antitumor effects of the conventional agents all correlated significantly with each other. For the colorectal cancer specimens, the pattern of UCN-01-sensitivity did not correlate with the patterns for 5-FU or MMC. In conclusion, UCN-01 may be useful for clinical application against gastric and colorectal cancer due to its different antitumor spectrum from conventionally available agents.