Abstract 4298: Comparative inhibitory effect of different Egyptian Withania somnifera root extracts on PTEN/PI3K/AKT signaling pathway in HepG2 cell line

Abstract

Abstract This study aimed to identify the anti-proliferative/survival/metastatic potential of different Egyptian Withania somnifera "Ashwagandha" root extracts through PI3K/AKT pathway modulation against HepG2 cell lines Background: Liver cancer is the most common malignancy of the digestive system with high death rate; surgical interventions considered as the most effective approach, but only about 20% of patients are suitable for surgery meanwhile, chemotherapeutic drugs for liver cancer have toxic adverse effects which restrict their effectiveness, therefore natural products combination with anticancer treatments could offer an attractive strategy for liver cancer treatment. Experimental procedures: Ethanolic crud extract was fractionated into five fractions according to polarity ex1 ex2 ex3 ex4 ex5 Sulphorhodamine-B assay used to evaluate the anticancer activity of the Withania somnifera factions in HepG2 cells and to calculate the half maximal inhibitory concentration IC50 of each fraction; The potential antitumor activity of the most effective fractions were assessed by investigating their effect on Apoptotic markers Caspase 3 8 9, Antioxidant markers GSH GST MDA, Survival and proliferation pathway PTEN AKT PI3K, Proliferation markers KI67 Survivin. Results: the crud extract and its fractions showed various cytotoxic effects; ex1 ex2 ex3 have more potent cytotoxic effect than the crude extract IC50= 59.6 78 92 140 μg/ml respectively, ex4 has a similar cytotoxic effect to the crude extract IC50=139 μg/ml while ex5 has the lowest cytotoxic effect IC50= 182 μg/ml; these results showed that the crud extract have no synergism between its active constituents. The most interesting finding is that ex2 has the second potent cytotoxic effect and it down regulate the expression level of AKT COX2 IL6 sFas MMP2 survivin Ki67 compared to the control significantly, while ex1 significantly up regulate the expression of PTEN and down regulate the expression of sFas. Interestingly, ex1 and ex2 showed the strongest effect in arresting HepG2 cells in G2/M phase compared to control and other fractions; the arrested cells activate multi pro-apoptotic pathways as they increases the activity of Caspase3 and Caspase 9. On the hand Caspase 8 activity was significantly increased in ex5 treated group which explain that ex5 induce its antiproliferative effect through membrane binding receptor so it has lowest cytotoxic effect Conclusion: The results showed that each extract differently exert its anticancer activity through modulating PI3K AKT signaling pathway at different levels and the most surprising finding was that petroleum ether fraction has potent promising anticancer capacity on HepG2 cells So, further investigation of each fraction is recommended to purify its active compounds which will offer promising opportunities to develop new candidate for targeted cancer therapy Citation Format: Nahla A. Elzefzafy, Amira Zaky, Wafaa A. Ahmed, Ahmad Bassiouny. Comparative inhibitory effect of different Egyptian Withania somnifera root extracts on PTEN/PI3K/AKT signaling pathway in HepG2 cell line [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4298.