Anticancer Activity of Ethnopharmacological Plants of Golestan Province/Iran against AGS, HT-29 and KYSE-30 Cell Lines through Promoting the Apoptosis and Immunomodulatory Effects

The anticancer and immunomodulatory effects of medicinal plants from Golestan province, as a promising source of cancer therapy against gastrointestinal cancer cell lines, were investigated in this study. The ethanolic root/aerial part extracts of 9 medicinal plants were screened for their cytotoxicity against normal mouse fibroblast cells (L-929) and three human cancer cell lines including gastric adenocarcinoma (AGS), colorectal adenocarcinoma (HT-29), and esophagus adenocarcinoma (KYSE-30) by performing MTT assay to determine the IC50 of the extracts. The in-vitro antioxidant activity, total phenolic (TPC), and total flavonoid content (TFC) of extracts was evaluated. Flow cytometry and Real-Time PCR were used for apoptosis assay and evaluation of expression of some genes involved in cell signaling; TLR-4, AKT, ERK1/2, and NFκB. Out of the 9 plant extracts screened, Arctiumlappa root (ALR), showed the most potent cytotoxicity against AGS, KYSE-30, and HT-29 cells with IC50 values of 10, 200, and 2030 µg/mL, respectively. In addition, ALR exerts high TPC (215.8 ± 0.3 mg GAE/g), TFC (69.03 ± 0.7 mg QUE/g) and high radical scavenging activity with IC50 (1250 ‎±‎ 0.1 µg/mL) in DPPH method. Also, ALR stimulates TLR-4 signaling, increased apoptosis, and decreased cancer cell attachment to the surface compared to the untreated cells. This plant, with a strong cytotoxic effect on cancer cells as well as increased apoptosis and its effect on molecules involved in TLR4 signaling as the immunomodulatory effect can be a suitable candidate for in-vivo studies in the future for cancer therapy.