Antiproliferative effects of Norartocarpetin isoflavone in human lung carcinoma cells are mediated via targeting Ras/Raf/MAPK signalling pathway, mitochondrial mediated apoptosis, S-phase cell cycle arrest and suppression of cell migration and invasion

Purpose: The main purpose of the current research work was to investigate the Anticancer activity of norartocarpetin - a plant derived isoflavone -in human lung carcinoma cells NCI-H460 and normal lung cell line MRC-9 along with studying its effects on cellular Apoptosis, DNA damage, cell migration and invasion and Ras/Raf/MAPK signalling pathways.

Methods: Cell proliferation was examined by CCK-8 assay while effects on Apoptosis were evaluated by acridine orange (AO)/ethidium bormide (EB) staining and Comet assay using fluorescence microscopy. In vitro wound healing assay was used for checking the effects on cell migration and transwell assay for invasion while western blot was used to evaluate the effects on the expression of Ras/Raf/MAPK proteins.

Results: The results showed that Norartocarpetin led to dose-dependent cytotoxic effects in NCI-H460 cells showing an IC50 value of 22 μM while in normal lung cells, the cytotoxic effects were much lower as shown by higher IC50 value of 85 μM. It also led to dose-dependent Apoptosis and induced DNA damage as shown by fluorescence microscopy. This molecule also inhibited cell migration and invasion dose-dependently, along with inhibiting MMP-9 expression. Norartocarpetin treatment also led to inhibition of the expression of Ras/Raf/MAPK proteins and also caused S-phase cell cycle arrest in these cells.

Conclusion: Norartocarpetin has a significant Anticancer activity in lung carcinoma cells and these effects are mediated via targeting Apoptosis, DNA damage, cell migration and invasion, cell cycle and inhibiting Ras/Raf/MAPK signalling pathways.