Potent Anticancer Effect of PET-Fraction (PET-F) in Comparison with Other Commercial Products on Canine Cancer Cells

A variety of nutritional supplements are commercially available for the potential therapeutic purpose for dogs and other domestic animals with cancers. However, the efficacy of these supplements on those cancer-bearing animals has not been verified and remains uncertain, due to the lack of the sufficient scientific studies/data. To address this important issue, we examined actual anticancer effects of five selected commercial products on the two types of canine cancer models in vitro. Among them, PET-Fraction (PET-F) obtained from maitake mushroom has been shown to have potent anticancer effect on canine cancer cells. In comparison with this PET-F, possible anticancer effects of the rest of four products were examined. Two of four products were found to have the significant anticancer effects on both cancer cells, while other two products had little effects. Nevertheless, PET-F exhibited the best anticancer effect. Cell cycle analysis indicated that the PETF-induced growth reduction was attributed to a G1 cell cycle arrest, and Western blot analysis further revealed that such a growth reduction was coupled with apoptosis. Moreover, anticancer activity of PET-F was remarkably enhanced with vitamin C, but no such synergistic effect was seen with other four products. Therefore, although two other products besides PET-F yet have anticancer activities, PET-F appears to be the most potent and promising commercial product that can be useful in effectively and safely treating canine cancers.