title: [Cloning and identification of fibrinogen gamma polypeptide (FGG) gene differentially expressed in human hepatocellular carcinoma].
abstract: OBJECTIVE
  Abnormal expression of genes is related to development and progression of hepatocellular carcinoma (HCC); however, the detailed mechanism is unclear yet because the known genetic information is not sufficient at present. This study was to explore cloning and identification of fibrinogen gamma polypeptide (FGG) gene differentially expressed in human hepatocellular carcinoma.
  
  
  METHODS
  The suppression subtractive hybridization was used to obtain subtracted cDNA products of HCC, then the products were cloned by T/A method. The differential expression of gene in HCC was identified by DNA sequencing analysis, Northern blot analysis, rapid amplification of cDNA end (RACE), and reverse transcription polymerase chain reaction (RT-PCR).
  
  
  RESULTS
  Firstly, a cDNA fragment of 787 nucleotides was screened from the subtracted cDNA clones, and it was further discovered that the expression of the cDNA fragment was higher significantly in human hepatocellular carcinoma cell strains of SMMC-7721 and HepG2 than in normal hepatocytes by Northern blot analysis. The RACE was carried out and the gene of 1 597 bp containing polyA in 3'end was obtained, which has an entire open reading frame encoding 437 amino acids. Homology analysis showed that this was a gene encoding human FGG. RT-PCR analysis of FGG showed that the amplification of cancerous tissues, especially in metastasis of HCC, was raised as compared to that of adjacent non-cancerous tissues.
  
  
  CONCLUSIONS
  Overexpression of FGG was discovered in SMMC-7721 and HepG2 cells. The up-regulation of FGG may be associated with the pathogenesis of HCC.
authors.affiliation: Department of Basic Medicine, Xinxiang Medical College, Xinxiang, Henan, 453003, PR China.
authors.forename: Bing-Lin
authors.initials: BL
authors.lastname: Fan
authors.forename: Wu-Ling
authors.initials: WL
authors.lastname: Zhu
authors.forename: Guo-Lin
authors.initials: GL
authors.lastname: Zou
authors.forename: Guo-Sheng
authors.initials: GS
authors.lastname: Luo
authors.forename: Chun-Lei
authors.initials: CL
authors.lastname: Xu
authors.forename: Wei-Xing
authors.initials: WX
authors.lastname: Zhao
mesh_terms: D001483:Base Sequence; D006528:Carcinoma, Hepatocellular / Q000209:etiology / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry; D005340:Fibrinogen / Q000235:genetics*; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008113:Liver Neoplasms / Q000209:etiology / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D018076:DNA, Complementary; D005340:Fibrinogen