Chaga Mushroom Inhibits Invasion and Promotes Apoptosis in Oral Cancer

Objectives: Chaga Mushroom (Inonotus obliquus) a rot fungus belongs to the hymenochaetaceae family of basidomycetes which grows primarily on branch stubs of birch trees in northern climates, but may be found on elm, alder, or beech trees. Basidomycetes mushrooms are regarded to have anti-tumor, immune modulating, cardiovascular, antiviral, antibacterial and anti-parasitic effects. Indeed studies have shown that Chaga mushroom extracts have anti-tumor effects, are able to suppress cellular proliferation in a time-dependent manner in human stomach cancer cell lines, possess antioxidant effects, and are able to protect cellular DNA from oxidative damage. Despite the increased usage and reported beneficial effects, the pharmacological actions of Chaga have not been well documented. Thus, relatively limited scientific evidence for the effectiveness and mechanism of action of Chaga has prevented its incorporation into mainstream medical care, and no reports exist describing its use in head and neck squamous cell carcinoma (HNSCC). Objective: In the present study, we describe a novel role for Chaga extract as an inhibitor of proliferation, migration and invasion in HNSCC, and as a promoter of apoptosis in these same cells.
Methods: Cellular proliferation, migration/invasion and apoptosis profiles were examined in Chaga-treated and untreated HNSCC cell lines (UM- SCC-6 and UM-SCC-1) using the WST-1 proliferation assay, established in vitro migration and invasion assays, and flow cytometry, respectively. The influence of Chaga on caspase-3 cleavage was evaluated using Western-blotting techniques.
Results: Chaga significantly inhibited 24-hour proliferation, migration and invasion in HNSCC cells in a dose-dependent manner. Furthermore, increasing concentrations of Chaga extract significantly induced early and late apoptosis, with a concomitant increase in caspase-3 cleavage.
Conclusions: This is the first report describing an anti-tumor role for Chaga in HNSCC cells. The present data suggests that Chaga holds promise as a chemotherapeutic agent against HNSCC.