Phuong Thao Nguyen1, Keishi Kanno2, Quoc Thang Pham1,3,4, Yuka Kikuchi1, Masaki Kakimoto1, Tomoki Kobayashi1, Yuichiro Otani1, Nobusuke Kishikawa1, Mutsumi Miyauchi5, Koji Arihiro6, Masanori Ito1, Susumu Tazuma1. 1. Department of General Internal Medicine, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan. 2. Department of General Internal Medicine, Hiroshima University Hospital, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan. kkanno@hiroshima-u.ac.jp. 3. Department of Molecular Pathology, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan. 4. Department of Pathology, University of Medicine and Pharmacy at Ho Chi Minh City, Ho Chi Minh City, Viet Nam. 5. Department of Oral Maxillo-Pathobiology, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan. 6. Department of Pathology, Hiroshima University Hospital, Hiroshima, Japan.
Abstract
PURPOSE: Deoxycholic acid (DCA), a secondary bile acid, is reportedly increased in the serum of patients with nonalcoholic steatohepatitis and animals with experimentally induced hepatocellular carcinoma (HCC), but its contribution to malignant behaviors of HCC has not been precisely clarified. This study aimed to examine the effect of DCA on hepatic stellate cells (HSCs), a major component of nonparenchymal cells in the liver, and its subsequent indirect effect on HCC cells. METHODS: LX2 cells, a human HSC line, were treated with DCA in vitro. Then, HuH7 cells, a human hepatoma cell line, were incubated in conditioned media of DCA-treated LX2 to investigate the subsequent effect focusing on malignant behaviors. RESULTS: DCA resulted in cellular senescence in LX2 with the decreased cell proliferation via cell cycle arrest at G0/1 phase, together with the induction of senescence-associated secretory phenotype (SASP) factors. To investigate the influence of SASP factors secreted by HSCs in response to DCA, HCC cells were treated with conditioned media that promoted cell migration and invasion via induction of epithelial mesenchymal transition. These changes were attenuated in the presence of neutralizing antibody against IL8 or TGFβ. Pathological analysis of surgical specimens from HCC patients revealed that senescent HSCs were detected in the stroma surrounding HCC. CONCLUSION: Our data suggest an important role of HSC senescence caused by DCA for the malignant biological behaviors of HCC via induction of SASP factors, particularly IL8 and TGFβ.
PURPOSE:Deoxycholic acid (DCA), a secondary bile acid, is reportedly increased in the serum of patients with nonalcoholic steatohepatitis and animals with experimentally induced hepatocellular carcinoma (HCC), but its contribution to malignant behaviors of HCC has not been precisely clarified. This study aimed to examine the effect of DCA on hepatic stellate cells (HSCs), a major component of nonparenchymal cells in the liver, and its subsequent indirect effect on HCC cells. METHODS: LX2 cells, a human HSC line, were treated with DCA in vitro. Then, HuH7 cells, a humanhepatoma cell line, were incubated in conditioned media of DCA-treated LX2 to investigate the subsequent effect focusing on malignant behaviors. RESULTS:DCA resulted in cellular senescence in LX2 with the decreased cell proliferation via cell cycle arrest at G0/1 phase, together with the induction of senescence-associated secretory phenotype (SASP) factors. To investigate the influence of SASP factors secreted by HSCs in response to DCA, HCC cells were treated with conditioned media that promoted cell migration and invasion via induction of epithelial mesenchymal transition. These changes were attenuated in the presence of neutralizing antibody against IL8 or TGFβ. Pathological analysis of surgical specimens from HCC patients revealed that senescent HSCs were detected in the stroma surrounding HCC. CONCLUSION: Our data suggest an important role of HSC senescence caused by DCA for the malignant biological behaviors of HCC via induction of SASP factors, particularly IL8 and TGFβ.