Active hexose-correlated compound down-regulates sex-determining region Y-box 2 of pancreatic cancer cells.

Active hexose-correlated compound (AHCC) is an extract of basidiomycete mushroom. It has been used as health food due to its efficacy of enhancing antitumor effects and reducing adverse effects of chemotherapy. Our previous research showed that AHCC down-regulated heat-shock protein (HSP)-27 and exhibited cytotoxic effects against gemcitabine-resistant pancreatic cancer cells. Sex-determining region Y-box 2 (SOX2) is reported to be up-regulated in other kinds of cancer cells and involved in carcinogenesis and malignancy. The aim of this study was to investigate the effects of AHCC on protein expression of SOX2 in the gemcitabine-resistant pancreatic cancer cell line KLM1-R. AHCC was applied to KLM1-R cells and expression of SOX2 was analyzed by western blotting. AHCC down-regulated SOX2 in KLM1-R cells. Nanog and Oct4, co-workers of SOX2 in maintaining pluripotency, did not exhibit any significant change in protein expression. We showed the potential of AHCC to be a candidate for combinatorial therapy in anticancer drug regimens. This result suggests that the target of AHCC in expressing therapeutic efficacy was not the pluripotent cells such as cancer stem cells (CSCs) but SOX2-specific.