title: c9, t11- conjugated linoleic acid induces HCC cell apoptosis and correlation with PPAR-γ signaling pathway.
abstract: OBJECTIVE
  Cis9, trans11 conjugated linoleic acid (c9, t11-CLA.) is one of the most important isomers of conjugated linoleic acid, which have a strong anti-tumor effects. Based on previous studies, we further explored the molecular mechanism of inducing cells apoptosis in human hepatocellular carcinoma cell line HepG2 and Hep3B.
  
  
  METHODS
  Cell Counting Kit 8 (CCK-8) assay was used to investigate the effects of c9, t11-CLA on cell viability and cell proliferation ability; The effects of c9, t11-CLA on cell apoptosis was analyzed by DNA ladder assay, immuno-fluorescence and flow cytometry, respectively. Apoptotic related gene (Bcl-2, Bcl-XL, Bcl-w, Mcl-1, Bax, Bak, Bad, Bid and Bim), PPAR family member (PPAR-α, PPAR-β and PPAR-γ), and Cox2 mRNA and protein expression were analyzed by RT-PCR and western blotting. ELISA assay was used to detect the content of Caspase-3.
  
  
  RESULTS
  Our data were confirmed that c9, t11-CLA could inhibit the HCC cells proliferation ability and decrease the cells viability. RT-PCR and western blotting assay verified that c9, t11-CLA obviously increased the transcription and protein expression levels of PPAR-γ. The synchronism and correlation between PPAR-γ and apoptotic proteins Bcl-2, Bax and Caspase-3 were found with a dose- and time-dependent manner. PPAR-γ inhibitor GW9662 and activator Rosilitazone were further verified that there was cooperative relation between them.
  
  
  CONCLUSIONS
  In our study, we first report that c9, t11-CLA induces apoptosis in HCC cells by activation of PPARγ-Bcl-2-Caspase-3 signal pathway. These results indicated that c9, t11-CLA will be useful for clinic therapy of anti-tumor and as a new regulator of PPAR-γ in the future.
authors.affiliation: Department of Pharmacy, 169 Hospital of PLA 369 Dongfeng Road, Zhuhui District, Hengyang City 421002, Hunan Province, China.
authors.forename: Guozhong
authors.initials: G
authors.lastname: Lu
authors.affiliation: Department of Pharmacy, 169 Hospital of PLA 369 Dongfeng Road, Zhuhui District, Hengyang City 421002, Hunan Province, China.
authors.forename: Guoqing
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Department of Pharmacy and Biological Sciences, University of South China Hengyang City 421002, Hunan Province, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Department of Pharmacy, 169 Hospital of PLA 369 Dongfeng Road, Zhuhui District, Hengyang City 421002, Hunan Province, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Zeng
authors.affiliation: Department of Pharmacy, 169 Hospital of PLA 369 Dongfeng Road, Zhuhui District, Hengyang City 421002, Hunan Province, China.
authors.forename: Ziqi
authors.initials: Z
authors.lastname: Xu
authors.affiliation: Department of Pharmacy, 169 Hospital of PLA 369 Dongfeng Road, Zhuhui District, Hengyang City 421002, Hunan Province, China.
authors.forename: Weichi
authors.initials: W
authors.lastname: Zeng
authors.affiliation: Department of Pharmacy, 169 Hospital of PLA 369 Dongfeng Road, Zhuhui District, Hengyang City 421002, Hunan Province, China.
authors.forename: Kebing
authors.initials: K
authors.lastname: Wang
keywords: Conjugated linoleic acid isomer; Hepatocellular carcinoma cell lines HepG2 and Hep3B; c9; cell apoptosis; peroxisome proliferators activated receptor γ (PPAR-γ); t11-CLA