Schisandrin B suppresses colon cancer growth by inducing cell cycle arrest and apoptosis via the CHOP signalling pathway

Abstract

Colon cancer is among the most lethal and prevalent malignant tumours in the world, and the lack of effective therapies highlights the need for novel therapeutic approaches. Schisandrin B (Sch B), a lignan extracted from the fruit Schisandra chinensis, has been reported for its anti-cancer properties. However, no studies to date have been done to characterise the exact molecular mechanisms regarding the anti-tumorigenic effect of Sch B in colon cancer. A comprehensive analysis of the molecular mechanism for the anti-tumorigenic effect of Sch B on human colon cancer cells was performed using combination of Raman spectroscopy, RNA-seq, computational docking and molecular biological experiments. The in vivo efficacy was evaluated by a mouse xenograft model. Sch B reduced cell proliferation and triggered apoptosis in human colon cancer cell lines. Raman spectroscopy, computational, RNA-seq, molecular and cellular studies revealed that Sch B activated unfolded protein responses by interacting with CHOP and upregulating CHOP, which thereby induced apoptosis. CHOP knockdown alleviated the Sch B-induced reduction in cell viability and apoptosis. Sch B reduced colon tumour growth in vivo. Our findings provide essential background for clinical trials examining the effects of Sch B in patients with colon cancer.