Suppression of the TNF-alpha level is mediated by Gan-Lu-Yin (traditional Chinese medicine) in human oral cancer cells through the NF-kappa B, AKT, and ERK-dependent pathways.
Oral cancer is one of the major causes of deaths in the male population of Taiwan. Gan-Lu-Yin (GLY) is used for an adjuvant treatment of Traditional Chinese Medicine in clinical patients. In this study, we investigated the molecular mechanisms in oral cancer cell lines after exposure to GLY. The cytometric bead-based array (CBA) method was used for the examining and analyzing of tumor necrosis factor-alpha (TNF-α) secretion level. TNF-α mRNA expression was determined by real-time PCR analysis. Nuclear factor kappa B (NF-κB) activity and other relative proteins were determined by NF-κB promoter assay, Western blotting, electrophoretic mobility shift assay (EMSA), and immuno-staining analyses. GLY decreased the secretion of TNF-α from the oral cancer CAL 27 cells. Furthermore, 2000 μg/mL of GLY significantly suppressed TNF-α mRNA expression of CAL 27 cells in a time-dependent manner. GLY reduced the levels of proteins, including nuclear NF-κB (p65 and p50), p-IKK (ser176), p-IκB, p-AKT, p-ERK, and nuclear Egr-1 in a time and dose-dependent manner. GLY also suppressed the NF-κB activity and translocation in CAL 27 cells. We suggest that GLY might promote the cure of oral cancer through decreasing the level of TNF-α cytokine, and these actions were mediated partially through the NF-κB, AKT, and ERK-dependent pathways in vitro. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1196-1205, 2016.