According to the report of the Department of Health (DOH) of Taiwan, the most common death causes are cancers. Hepatocellular carcinoma (HCC) is the first commonest cancer in men and the second commonest cancer in women. Hispolon is a component from Phellinus Linteus, one of the traditional Chinese medical herbs. However, the underlying mechanism of the anti-tumor effects of Hispolon remains to be clarified. In the present study, Hispolon was used to evaluate growth inhibition on human liver cancer cell lines (Hep G2、Hep 3B and J5 cell).The inhibitory effects of Hispolon on the growth of tumor cells were determined by a MTT assay. Hispolon inhibited the Hep G2, Hep 3B and J5 cells growth in the time-dependent and dose-dependent manners. Hispolon had the best suppression effect on Hep 3B. Hispolon induced cell cycle arrest in the S phase by flow cytometric analysis. In the DAPI staining, apoptotic cells were identified by morphological changes associated with condensed chromatin, fragmentation and apoptotic bodies. In the DNA fragmentation, Hispolon activated endonucleases cleave DNA at the linker regions between nucleosomes to produce 180 bp oligonucleosome (DNA ladder). From Western blot analysis, Hispolon decreased the protein levels of cyclins E、A and CdK 2, increasing the protein levels of p21 and p27, which those could induce S phase arrest. Hispolon increased the protein levels of Fas、Bid、Bax、cleaved caspase-8、cleaved caspase-9、cleaved caspase-3 and cytochrome c in Hep 3B cell. However, Hispolon decreased the protein levels of Bcl-2. Therefore, the results was evaluated that Hispolon-induced Hep3B cell apoptosis was possibly mediated through the extrinsic pathway system and the extrinsic pathway. Taken together, the results of this study, Hispolon down-regulated ERK1/2、JNK-P and p38-P expression then turned on the caspase cascade, which executed apoptosis in Hep 3B cell.
