Effects of Huaier aqueous extract on proliferation and apoptosis in the melanoma cell line A875.

In recent years, an aqueous extract of the fungus Trametes robiniophila Murriell 1907 (Huaier) has been commonly used in China for complementary cancer therapy. However, the mechanisms of its anticancer effects are largely unknown. In the present study, we aimed to investigate the effects of Huaier extract on the inhibition of proliferation and promotion of apoptosis in a melanoma cell line, A875, and to explore the possible mechanisms of its anticancer effects. Cell proliferation was measured using a Cell Counting Kit-8 (CCK8) and PCNA-Western blot. The cell cycle distribution, and apoptosis levels were analyzed by flow cytometry, and Western blot was used to test the apoptotic pathways. We found that Huaier extract strongly inhibited cell proliferation of the A875 melanoma cells and induced G2/M arrest and apoptosis in a time- and dose-dependent manner. P53 expression was increased and cell apoptosis executed by caspase-3. Down-regulation of Bcl-2 and up-regulation of Bcl2-associated X protein (BAX) indicated that Huaier extract induced apoptosis through the mitochondrial pathway. As expected, the inhibitor Huaier decreased melanoma cell line A875 proliferation, and induced apoptosis in a time- and dose-dependent manner. Our findings indicate that Huaier extract is an effective complementary agent for cancer treatment of melanoma.