A preliminary study of the anti-cancer effect of tanshinone on hepatic cancer and its mechanism of action in mice

Objective: There were some experimental researches in vitro , which showed that tanshinonoe (Tan) had cytotoxic activities against some cancer cell lines. But there was no report of anti-cancer activity of Tan in vivo . This experimental study was performed to confirm the anti-cancer activity of Tan in vivo . Methods: Hepatic carcinoma H 22 bearing mice were treated with DMSO, 5-Fu, and Tan, at the end of experiment, the mice were sacrificed, tumor tissues were separated and weighed, and the tumor inhibitory rate was calculated, 3 times of the same experiments were performed. The proliferating kinetics of hepatic carcinoma H 22 cells in mice was measured by bromodeoxyuridine labeling in vivo and immunohistochemical staining of the proliferating cell nuclear antigen (PCNA) in tumor tissues. Results: The tumor inhibitory rates of Tan were 50.0%, 38.5%, and 40.6% in 3 experiments, respectively, compared with those of the DMSO-treated control groups, the differences were significant statistically ( P <0.01). The Brdu labeling and PCNA positive cells were 51.8±7.9 and 451.1±26.1, respectively, which were significantly lower than those of controls (84.4±24.3, 694.8±117.1) ( P <0.01). Conclusion: Tan had anti-cancer effect on hepatic carcinoma in vivo ; The mechanisms of action might be associated with inhibition of DNA synthesis, PCNA expression and DNA polymerase δ activity of tumor cells.