A Study On The Roles Of Tissue Inhibitor Of Metalloproteinases (Doxycycline) On Human Colorectal Cancer Bearing Nude Mice

Objective To investigate the inhibitory effects of Doxycycline on the growth of human colorectal cancer implanted in nude mice.So that we can look for a new therapy for human colorectal cancer.Methods Ten BALB/C nude mice were randomly divided into control group and study group equally.Human colorectal cancer cell line LoVo was inoculated subcutaneously into nude mice to form transplantation tumors.Saline was injected to mice in control group and Doxycycline was injected to mice in study group.The changes of tumors in both groups were recorded and the curve of tumor growth was also observed and the inhibitory rate of tumor was calculated.Results Doxycycline significantly inhibited the growth of colorectal cancer xenograf- ts in nude mice. The first 18 days from the experimental group and control group differences in tumor size(1.0691±0.2148)cm3,(0.6337±0.1088)cm3, the first 26 days of tumor control group and experimental group were tumor size (1.7558±0.2038) cm3, (0.8898±0.0808) cm3.The volume of transplantation tumor reduced with the inhibitory rate of 49.7%,which showed that the former was significantly lower than that of the control group (F=78.041 p<0.01).Conclusion Doxycycline may inhibit the growth of colorectal cancer bearing nude mice.Which maybe uses for the therapy of human colorectal cancer.