Hydrophobic constituents and their potential anticancer activities from Devil's Club (Oplopanax horridus Miq.)

Devil's Club (Oplopanax horridus) is one of the most important spiritual and medicinal plants to many indigenous peoples of Alaska and the Pacific Northwest. It is widely used for external and internal infections as well as arthritis, respiratory ailments, digestive tract ailments, broken bones, fever, headaches, and cancer.

To investigate hydrophobic constituents and their potential anticancer activity from Devil's Club, Oplopanax horridus.

The root bark extract of Oplopanax horridus was isolated by chromatographic techniques. Structures of isolated compounds were identified by spectroscopic methods and comparison with published data. The anti-proliferation of isolated hydrophobic constituents in human breast cancer MCF-7 cells, human colon cancer SW-480 and HCT-116 cells were tested. The potential mechanism of anti-proliferation was also investigated using cell cycle and apoptosis assays.

Six compounds were isolated and structurally identified as 9,17-octadecadiene-12,14-diyne-1,11,16-triol, 1-acetate (1), oplopandiol acetate (2), falcarindiol (3), oplopandiol (4), trans-nerolidol (5) and t-cadinol (6). These compounds showed potential anticancer activities on human breast cancer and colon cancer cells, of which compound 3 possesses the strongest activity. Further cell cycle and apoptosis tests by flow cytometry showed the polyacetylenes 1-4 induced HCT-116 cell arresting in G2/M phase and inhibited proliferation by the induction of apoptosis at both earlier and later stages.

These results provide promising baseline information for the potential use of Oplopanax horridus, as well as some of the isolated compounds in the treatment of cancer.