Objective: To investigate the antitumor activity of arsenic trioxide on mice experimental liver cancer.
Methods: Mice bearing HepA solid and ascitic liver tumor were used in vivo experiments.
Results: The tumor-bearing mice were treated with arsenic trioxide 2.0mg/kg/d and 3.5mg/kg/d intravenously for 7 days. After the administration of arsenic trioxide, the growth of solid tumor were obviously inhibited, the inhibitory rate were 31.63% and 42.13% respectively. Under the inspection of transmission electron microscope, some cells of the solid tumor showed the typically morphological characteristics of apoptosis. The apoptotic cells were detected by in situ TdT-mediated dUTP nick end labeling (TUNEL). The immunohistochemical staining showed that the number of bcl-2 protein positive cells decreased, but the number of bax protein positive cells increased. It also showed that arsenic trioxide could significantly prolong the mean survival time in ascitic-tumor-bearing mice, the prolonging rate of life span was 59.29% and 76.69% respectively. The sub-G1 peaks were observed by flow cytometry on the ascitic specimen and the apoptotic rate were 25.98% and 53.17% respectively.
Conclusion: arsenic trioxide has obvious antitumor activity on HepA liver tumor-bearing mice. The mechanism of arsenic trioxide may mainly be inducing liver cancer cells to undergo apoptosis, which may be related to downregulate the expression of bcl-2 genes and upregulate the expression of bax genes.