title: Epimorphin promotes human hepatocellular carcinoma invasion and metastasis through activation of focal adhesion kinase/extracellular signal-regulated kinase/matrix metalloproteinase-9 axis.
abstract: The high incidence rate of hepatocellular carcinoma (HCC) is mainly the result of frequent metastasis and tumor recurrence. Unfortunately, the underlying molecular mechanisms driving HCC metastasis are still not fully understood. It has been demonstrated that tumor stroma cells contribute to primary tumor growth and metastasis. Within the HCC environment, activated hepatic stellate cells (HSCs) can release a number of molecules and enhance cancer cell proliferation and invasiveness in a paracrine manner. Here, for the first time, we demonstrate that epimorphin (EPM; also called syntaxin-2), an extracellular protein, is strongly elevated in activated HSCs within tumor stroma. We show that knockdown of EPM expression in HSCs substantially abolishes their effects on cancer cell invasion and metastasis. Ectopic expression of EPM in HCC cancer cells enhances their invasiveness; we demonstrate that the cells expressing EPM have markedly increased metastasis potential. Furthermore, EPM-mediated invasion and metastasis of cancer cells is found to require up-regulation of matrix metalloproteinase-9 (MMP-9) through the activation of focal adhesion kinase (FAK)/extracellular signal-regulated kinase (ERK) axis.
  
  
  CONCLUSIONS
  Our results show that EPM, secreted by activated HSCs within HCC stroma, promotes invasion and metastasis of cancer cells by activating MMP-9 expression through the FAK-ERK pathway.
authors: Stem Cell and Regenerative Medicine Lab, Beijing Institute of Transfusion Medicine, Beijing, China.
authors: Ya-Li
authors: YL
authors: Jia
authors: Lei
authors: L
authors: Shi
authors: Jun-Nian
authors: JN
authors: Zhou
authors: Chun-Jiang
authors: CJ
authors: Fu
authors: Lin
authors: L
authors: Chen
authors: Hong-Feng
authors: HF
authors: Yuan
authors: Yun-Fang
authors: YF
authors: Wang
authors: Xin-Long
authors: XL
authors: Yan
authors: Ying-Chen
authors: YC
authors: Xu
authors: Quan
authors: Q
authors: Zeng
authors: Wen
authors: W
authors: Yue
authors: Xue-Tao
authors: XT
authors: Pei
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000378:metabolism* / Q000556:secondary*; D002455:Cell Division / Q000502:physiology; D002465:Cell Movement / Q000502:physiology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D051417:Focal Adhesion Kinase 1 / Q000378:metabolism; D056945:Hep G2 Cells; D055166:Hepatic Stellate Cells / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008099:Liver / Q000378:metabolism / Q000473:pathology; D008113:Liver Neoplasms / Q000378:metabolism* / Q000473:pathology*; D020935:MAP Kinase Signaling System / Q000502:physiology*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D009361:Neoplasm Invasiveness; D050827:Syntaxin 1 / Q000378:metabolism*
chemical_list: C074558:STX2 protein, human; D050827:Syntaxin 1; D051417:Focal Adhesion Kinase 1; C496050:PTK2 protein, human; D048049:Extracellular Signal-Regulated MAP Kinases; D020780:Matrix Metalloproteinase 9