Abstract: OBJECTIVE: To study the inhibitory effect of sodium norcantharidin lipid microsphere injection on nude mice bearing human carcinoma A549. METHODS: Animal model of human lung cancer was established by inoculating human carcinoma A549 cells to BALB/c nude mice. 11 days after inoculation,mice were randomly divided into control group,positive control group,and other three groups with different doses of sodium norcantharidin lipid microsphere injection. The mice received physiological saline,2.5 mg/kg sodium norcantharidin injection,and 1.25,2.5 or 5 mg/kg sodium norcantharidin lipid microsphere injection at 1 d,4 d,8 d,11 d,15 d,18 d,and 22 d after grouping. The tumor volume (V_t),relative volume (V_RT),and the increment rate (T/C) were measured at 7 d,14 d,and 24 d after the first injection. The weight of tumors and the growth inhibition rate in vivo were measured at 24 d after the first injection. RESULTS: The tumor volume and the relative volume of all treated groups were much smaller than the group with negative control 7 days after the first injection,and the difference was significant (P<0.05). These effects showed drug dose-effect relationships (r_{7 d}=0.994,r_{14 d}=0.993,r_{24 d}=0.996). The tumor increment rate of all treated groups were lower than 25%,especially the medium dose and the high dose groups which dropped to below 20%. The average tumor weights of the treated groups were lower than the control group (P<0.01). The growth inhibition rates were more than 50%. CONCLUSION: Sodium norcantharidin lipid microsphere injection effectively inhibited the growth and reduced increment rate of human carcinoma A549 transplanted in nude mice.

Key words: sodium norcantharidin, lipid microsphere, lung cancer, antitumor, nude mice