Inhibitory effect of oral administration of Sangwhang mushroom (Phellinus linteus) grown on germinated brown rice on experimental lung metastasis and tumor growth in mice

Hispolon induces apoptosis through JNK1/2-mediated activation of a caspase-8, -9, and -3-dependent pathway in acute myeloid leukemia (AML) cells and inhibits AML xenograft tumor growth in vivo

Hispolon is an active phenolic compound of Phellinus igniarius, a mushroom that was recently shown to have antioxidant and anticancer activities in various solid tumors. Here, the molecular mechanisms by which hispolon exerts anticancer effects in acute myeloid leukemia (AML) cells was investigated. The results showed that hispolon suppressed cell proliferation in the various AML cell lines. Furthermore, hispolon effectively induced apoptosis of HL-60 AML cells through caspases-8, -9, and -3 activations and PARP cleavage. Moreover, treatment of HL-60 cells with hispolon induced sustained activation of JNK1/2, and inhibition of JNK by JNK1/2 inhibitor or JNK1/2-specific siRNA significantly abolished the hispolon-induced activation of the caspase-8/-9/-3. In vivo, hispolon significantly reduced tumor growth in mice with HL-60 tumor xenografts. In hispolon-treated tumors, activation of caspase-3 and a decrease in Ki67-positive cells were observed. Our results indicated that hispolon may have the potential to serve as a therapeutic tool to treat AML.

Identification of an anticancer compound against HT-29 cells from Phellinus linteus grown on germinated brown rice

OBJECTIVE

To isolate and identify the anticancer compound against proliferation of human colon cancer cells from ethyl acetate (EtOAc) extract of Phellinus linteus grown on germinated brown rice (PB).

METHODS

EtOAc extract of PB was partitioned with n-hexane, EtOAc, and water-saturated n-butanol. Anticancer compound of n-hexane layer was isolated and identified by HPLC and NMR, respectively. Cytotoxicity against HT-29 cells was tested by SRB assay.

RESULTS

The n-hexane layer obtained after solvent fractionation of PB EtOAc extracts showed a potent anticancer activity against the HT-29 cell line. Atractylenolide I, a eudesmane-type sesquiterpene lactone, a major anticancer substance of PB, was isolated from the n-hexane layer by silica gel column chromatography and preparative-HPLC. This structure was elucidated by one- and two-dimensional NMR spectroscopic data. Atractylenolide I has not been reported in mushrooms or rice as of yet. The isolated compound dose-dependently inhibited the growth of HT-29 human colon cancer cells.

CONCLUSIONS

Atractylenolide I might contribute to the anticancer effect of PB.