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.