Polyphyllin G exhibits antimicrobial activity and exerts anticancer effects on human oral cancer OECM-1 cells by triggering G2/M cell cycle arrest by inactivating cdc25C-cdc2

Plant Natural Products have long been considered to be important sources of bioactive molecules. A large number of antimicrobial and Anticancer agents have been isolated form Plants. In the present study we evaluated the antimicrobial and Anticancer activity of a plant derived secondery metabolite, Polyphyllin G. The results of Antibacterial assays showed that Polyphyllin G prevented the growth of both Gram-positive and Gram-negative bacteria with minimum inhibitory concentrations (MICs) ranging from 13.1 to 78 μg/ml. Antifungal activity measured as inhibition of mycelium growth ranged between 38.32 and 56.50%. Further Polyphyllin G was also evaluated against a panel of Cancer cell lines. The IC₅₀ of Polyphyllin G ranged from 10 to 65 μM. However the IC₅₀ of Polyphyllin G was found to be comparatively high (120 μM) against the normal FR2 Cancer cell line. The lowest IC₅₀ of 10 μM was found against the oral Cancer cell line OECM-1. Therefore further studies were carried out on this cell line only. Our results indicated that Polyphyllin G induced cell arrest in oral Cancer OECM-1 cells by inactivation of cdc25C-cdc22 via ATM-Chk 1/2 stimulation. Therefore, we propose that Polyphyllin G might prove a lead molecule in the management of oral cancers and at the same time may prevent the growth of opportunistic microbes.