Synergistic Evaluation of Ginger and Licorice Extracts in a Mouse Model of Colorectal Cancer

Herbal medicine can be used to overcome the side effects of conventional treatments. This study aimed to evaluate the anticancer activities of ginger and licorice extracts, as well as the synergistic effects of their combination. Ginger ethanolic extract (GEE) and licorice methanolic extract (LME) were isolated by a Soxhlet extractor. Next, the anti-proliferative activity of the extracts, apoptosis induction, tumor growth inhibition, and tumor-infiltrating T lymphocytes were investigated. The MTT (3-[4, 5-dimethylthiazol-2-yl]-2, five diphenyl tetrazolium bromide) assay showed that GEE and LME decreased the CT26 cell viability in a dose-dependent manner; however, the GEE + LME combination was more effective (P < 0.05). The CT26 cells treated with each extract showed a significant increase in Bax/Bcl-2 ratio and caspase-3 gene expression, especially in the GEE + LME group (P < 0.001). Tumor volume significantly reduced in the GEE + LME group, compared to the negative controls. Finally, mice treated with GEE + LME showed a significant increase in the CTL/Treg cell ratio (P < 0.001) and Bax/Bcl2 ratio (P < 0.05). The study results revealed that GEE + LME can suppress cancer cell growth, increase apoptosis, and improve CTL infiltrating to the tumor site in a synergetic manner in-vivo and in-vitro. Therefore, the prepared mixture can be used in future clinical trials.