Honokiol inhibits gallbladder cancer proliferation and epithelial mesenchymal transformation by suppressing TMPRSS4-induced PI3K/AKT activation

Abstract

Purpose: To determine the role of TMPRSS4 in gallbladder cancer (GBC).
 Methods: Quantitative reverse-transcription-polymerase chain reaction (qRT-PCR) and western blotting were used to evaluate the expression of genes, while CCK-8 kit and foci formation assay were used to assess cell growth in GBC-SD and non-obliterative zone (NOZ) cell lines. Cell apoptosis was evaluated by flow cytometry, while cell migration and cell invasion were determined by Transwell assay in GBCSD and NOZ cell lines.
 Results: TMPRSS4 was highly expressed in GBC cells, compared to normal cell, HIBEC. Overexpression of TMPRSS4 enhanced cell viability and 2D foci formation in GBC-SD (stratified) and NOZ; however, knockdown of TMPRSS4 reduced cell proliferation and colony formation in the cell lines (p < 0.05). TMPRSS4 deficiency increased cell apoptosis but its reinforced expression decreased cell apoptosis in GBC cell lines (p < 0.05). Moreover, TMPRSS4 positively regulated cell invasion and migration in GBC cells by upregulating TWIST1, vimentin and N- cadherin. TMPRSS4 also regulated the activation of PI3K/AKT signal pathway. Furthermore, honokiol inhibited gallbladder cancer proliferation and migration, and induced cell apoptosis by suppressing TMPRSS4-induced PI3K/AKT activation (p < 0.05).
 Conclusion: TMPRSS4 plays an important role in regulating cell growth, apoptosis and metastasis of gallbladder cancer cells (GBC). Thus, TMPRSS4 might be a new biomarker in gallbladder cancer.