title: Inhibitory effects of deleted in liver cancer 1 gene on gallbladder cancer growth through induction of cell cycle arrest and apoptosis.
abstract: OBJECTIVE
  The biological function of tumor suppressor deleted in liver cancer 1 (DLC1) has been investigated in several types of human cancer, but its role in gallbladder cancer (GBC) is yet to be determined. In this research, we conducted in vitro and in vivo analysis to evaluate the inhibitory activities of DLC1 gene against GBC growth.
  
  
  METHODS
  DLC1 expression in GBC tissues and cell lines was examined by immunohistochemical staining, reverse transcription polymerase chain reaction, and Western blot assay. The in vitro and in vivo effects of ectopic DLC1 expression on cell growth were evaluated. In addition, the effects of ectopic DLC1 expression on cell cycle, apoptosis, and migration were also evaluated. The expressions of cell cycle-related and apoptosis-related proteins were examined.
  
  
  RESULTS
  The downregulation of DLC1 expression was a common event in GBC tissues and cell lines. Restoration of DLC1 expression in GBC-SD and NOZ cells significantly reduced cell proliferation, migration in vitro, and the ability of these cells to form tumors in vivo. Restoration of DLC1 expression arrested GBC-SD and NOZ cells in G0/G1 phase through inducing p21 in a p53-independent manner. In addition, restoration of DLC1 expression induced extrinsic and intrinsic apoptotic pathway through promoting the expressions of Fas L/FADD, Bax, cytochrome c, cleaved caspase-8, -9, -3, and cleaved poly-(ADP-ribose) polymerase and suppressing bcl-2 expression in GBC-SD and NOZ cells.
  
  
  CONCLUSIONS
  Our findings suggested that dysregulated expression of DLC1 is involved in proliferation and invasion of GBC cells and may serve as a potential therapeutic target.
authors: Department of General Surgery, Xinhua Hospital, Affiliated to School of Medicine, Shanghai Jiaotong University, Shanghai, China.
authors: Yiyu
authors: Y
authors: Qin
authors: Bingfeng
authors: B
authors: Chu
authors: Wei
authors: W
authors: Gong
authors: Jiandong
authors: J
authors: Wang
authors: Zhaohui
authors: Z
authors: Tang
authors: Jun
authors: J
authors: Shen
authors: Zhiwei
authors: Z
authors: Quan
mesh_terms: D017209:Apoptosis / Q000235:genetics; D020169:Caspases / Q000378:metabolism; D002453:Cell Cycle / Q000235:genetics; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000378:metabolism; D045304:Cytochromes c / Q000378:metabolism; D053222:Fas Ligand Protein / Q000378:metabolism; D020690:GTPase-Activating Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D005706:Gallbladder Neoplasms / Q000235:genetics* / Q000473:pathology* / Q000628:therapy; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D066298:In Vitro Techniques; D058990:Molecular Targeted Therapy; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism; D025521:Tumor Suppressor Proteins / Q000235:genetics* / Q000378:metabolism / Q000502:physiology*; D051028:bcl-2-Associated X Protein / Q000378:metabolism
chemical_list: C494826:BAX protein, human; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; C112352:DLC1 protein, human; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D020690:GTPase-Activating Proteins; D016159:Tumor Suppressor Protein p53; D025521:Tumor Suppressor Proteins; D051028:bcl-2-Associated X Protein; D045304:Cytochromes c; D020169:Caspases
keywords: apoptosis; cell cycle; deleted in liver cancer 1; gallbladder cancer; gene therapy