In vitro and in vivo evaluation of anisomycin against Ehrlich ascites carcinoma.

Anisomycin eminently inhibits cell proliferation in vitro. The aim of this study was to explore the potential of anisomycin to treat tumors in vivo and its mechanism(s) of action. The results showed that peritumoral administration of anisomycin significantly suppressed Ehrlich ascites carcinoma (EAC) growth resulting in the survival of approximately 60% of the mice 90 days after EAC inoculation. Enhancement of infiltrating lymphocytes was noted in the tumor tissue, which was dramatically superior to adriamycin. The growth inhibitory rate of EAC cells was enhanced with increasing concentrations of anisomycin, following an enhanced apoptotic rate. The total apoptotic rate induced by 160 ng/ml of anisomycin was higher when compared to that induced by 500 ng/ml of adriamycin. DNA breakage and nanostructure changes were also noted in the EAC cells. The levels of caspase-3 mRNA, caspase-3 and cleaved-caspase-3 proteins in the anisomycin‑treated EAC cells were augmented in a dose- and time-dependent manner, following the activation of caspase-8 and caspase-9, which finally triggered PARP cleavage. The cleaved-caspase-3, cleaved-caspase-8 and cleaved-caspase-9 proteins were mainly localized in the nuclei of the cells. These results indicate that anisomycin efficaciously represses in vitro and in vivo growth of EAC cells through caspase signaling, significantly superior to the effects of adriamycin. This suggests the potential of anisomycin for the treatment of breast cancer.