The ethyl acetate extract of Phellinus linteus grown on germinated brown rice induces G0/G1 cell cycle arrest and apoptosis in human colon carcinoma HT29 cells.
Phytother Res. 2009 Dec 8. Epub 2009 Dec 8. PMID: 19998418
Department of Bioscience and Biotechnology, Konkuk University, 1 Hwayang-dong, kwangjin-gu, Seoul, 143-701, Korea.
It is well known that Phellinus linteus has a variety of biological functions, such as antitumor and immunomodulating activities. In our previous studies, we developed a P. linteus grown on germinated brown rice (PBR) and found that organic solvent extracts of PBR possessed immunomodulating activity to regulate a balance of cytokine network in mice. The components of PBR are ergosterol peroxide, gamma-aminobutyric acid (GABA) and Beta-glucan. In this study, we demonstrate that an organic solvent extract of P. linteus grown on PBR induced apoptotic cell death through the induction of G(0)/G(1) arrest of cell cycle and the apoptosis via DNA fragmentation in human colon carcinoma HT-29 cells. Cell death induced by the extract of P. linteus grown on PBR was shown to be associated with the upregulation of p21(CIP1/WAF1), the downregulation of cyclin D1, anti-apoptotic protein, Bcl-2, the release of cytochrome c, and the activation of caspase-9, caspase-3 and caspase-8. This study suggests that the ethyl acetate extract of P. linteus grown on PBR induces apoptosis accompanied by cell cycle arrest at G(0)/G(1) phase and regulates apoptosis-regulatory proteins, which may be applicable to anticancer therapy. Copyright (c) 2009 John Wiley&Sons, Ltd.