title: Biological effects of RNAi targeted inhibiting Tiam1 gene expression on cholangiocarcinoma cells.
abstract: OBJECTIVE
  To investigate the characteristics of Tiam1 gene expression in human cholangiocarcinoma tissues and benign bile duct tissues, and to analyze the correlations between Tiam1 gene expression and the degree of tumor differentiation, invasive and metastatic abilities. To explore the effect of targeted inhibiting Tiam1 gene expression on proliferation and migration activity of human cholangiocarcinoma cells.
  
  
  METHODS
  Expression of Tiam1 in 83 cases of cholangiocarcinoma tissues and 25 cases of benign bile tissues was detected using immunohistochemistry. The clinical data of patients with cholangiocarcinoma were collected. The correlations between Tiam1 gene expression and the clinicopathologic features in patients with cholangiocarcinoma were analyzed. The human cholangiocarcinoma RBE cells were divided into 3 groups. Cells in experimental group and control group were respectively transfected with Tiam1 shRNA lentiviral vectors and negative shRNA lentiviral control vectors. Cells in blank group received no treatment. Real-time PCR endogenesis was used to verify Tiam1 gene expression. Cell cycle experiments and MTT assay were used to measure cell proliferation activity. Transwell test was used to detect cell migration activity.
  
  
  RESULTS
  The negative rate Tiam1 protein expression in cholangiocarcinoma tissues was significantly higher than that in benign bile tissues (P<0.001). Tiam1 protein expression in cholangiocarcinoma tissues had correlations with cholangiocarcinoma differentiation degree, TNM stage and lymph node metastasis (P<0.05), and had no significant correlations with gender, age and distant metastasis (P>0.05). Real-time PCR detection indicated that Tiam1 expression of experimental group was significantly lower than that in control group and blank group (P<0.05), demonstrating that Tiam1 shRNA was effective on Tiam1 gene silencing in RBE cells. Cell cycle experiment showed that the percentage of S phase in cell cycle in experimental group was lower than that in control group and blank group (P<0.05), demonstrating that after the down-regulation of Tiam1 gene expression, the speed of cell proliferation was inhibited. MTT assay results showed that the total growth speed in experimental group was significantly lower than that in control group and blank group (P<0.05), indicating that the proliferation activity of cholangiocarcinoma cells was inhibited after targeted inhibition of Tiam1 gene expression. Transwell detection results showed that the metastasis rate in experimental group was significantly lower than that in control group and blank group (P<0.05), demonstrating that targeted inhibition of Tiam1 gene expression could significantly inhibit migration ability of RBE cells.
  
  
  CONCLUSIONS
  Tiam1 expression significantly increased in cholangiocarcinoma tissues, and increased along with the degree of malignancy of cholangiocarcinoma. Targeted silencing Tiam1 expression could inhibit proliferation and migration activity of cholangiocarcinoma cells.
authors.affiliation: Department of Hepatobiliary Surgery, Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University Changsha, Hunan, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cheng
authors.affiliation: Department of Hepatobiliary Surgery, Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University Changsha, Hunan, China.
authors.forename: Yaling
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Hepatobiliary Surgery, Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University Changsha, Hunan, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Zuo
authors.affiliation: Department of Hepatobiliary Surgery, Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University Changsha, Hunan, China.
authors.forename: Xinmin
authors.initials: X
authors.lastname: Yin
authors.affiliation: Department of Hepatobiliary Surgery, Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University Changsha, Hunan, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Jiang
authors.affiliation: The Third Hospital of Central South University Changsha, Hunan, China.
authors.forename: Daojin
authors.initials: D
authors.lastname: Chen
authors.affiliation: Department of Hepatobiliary Surgery, Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University Changsha, Hunan, China.
authors.forename: Chuang
authors.initials: C
authors.lastname: Peng
authors.affiliation: Department of Hepatobiliary Surgery, Hunan Provincial People's Hospital, The First Affiliated Hospital of Hunan Normal University Changsha, Hunan, China.
authors.forename: Jianhui
authors.initials: J
authors.lastname: Yang
mesh_terms: D000328:Adult; D000368:Aged; D001650:Bile Duct Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology / Q000628:therapy*; D002453:Cell Cycle; D002454:Cell Differentiation; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D018281:Cholangiocarcinoma / Q000235:genetics / Q000378:metabolism / Q000556:secondary / Q000628:therapy*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D020662:Guanine Nucleotide Exchange Factors / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D009367:Neoplasm Staging; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism; D000067492:RNAi Therapeutics; D000075684:T-Lymphoma Invasion and Metastasis-inducing Protein 1; D014162:Transfection
chemical_list: D020662:Guanine Nucleotide Exchange Factors; D034741:RNA, Small Interfering; D000075684:T-Lymphoma Invasion and Metastasis-inducing Protein 1; C087334:TIAM1 protein, human
keywords: Cholangiocarcinoma; RNA; Tiam1; lentiviral vector