title: [Small interfering RNA targeting to hepatitis B virus X gene and 5-aza-2'-deoxycytidineon inhibited growth of the subcutaneous implanted tumor of hepatocellular carcinoma in nude mice].
abstract: OBJECTIVE
  To investigate the anti-tumor effect of small interfering RNA targeting to HBV X gene (X-siRNA) and 5-aza-2'-deoxycytidine (5-aza-dC) on HBV-related hepatocellular carcinoma.
  
  
  METHODS
  X-siRNA and control siRNA were synthesized. HepG2/GFP-HBx cells were treated with X-siRNA, and the levels of HBV X mRNA were detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). Nude mice were inoculated with HepG2/GFP and HepG2/GFP-HBx cells subcutaneous respectively to establish implant models of hepatocellular carcinoma, and were treated with X-siRNA, 5-aza-dC alone or in combination, and tumor growth was observed. The methylation of p16 gene promoter was detected by methylation specific polymerase chain reaction (MSP).
  
  
  RESULTS
  RT-PCR showed the expression of HBV X mRNA in HepG2/GFP-HBx cells was inhibited markedly by X-siRNA. The nude mice experiment showed that the gross tumor volume was much bigger in HepG2/GFP-HBx group than that in HepG2/GFP group (P < 0.05). The growth of palpable tumors in X-siRNA or 5-aza-dC treatment group notably decreased (P < 0.05). MSP analysis showed that p16 gene methylation was observed in HepG2/ GFP-HBx-caused palpable tumors, while no methylation was detected in HepG2/GFP group. However, after treatment with X-siRNA or 5-aza-dC, p16 gene methylation reduced.
  
  
  CONCLUSIONS
  HBV X-siRNA and methylation inhibitor can inhibit the growth of hepatoma cells via reversing p16 methylation.
authors.affiliation: Department of Infectious Diseases, The Third Affiliated Hospital of SUN Yat-sen University, Guangzhou 510630, China.
authors.forename: Li
authors.initials: L
authors.lastname: Mai
authors.forename: Lin
authors.initials: L
authors.lastname: Yang
authors.forename: Jian-Yu
authors.initials: JY
authors.lastname: Kuang
authors.forename: Shao-Quan
authors.initials: SQ
authors.lastname: Zhang
authors.forename: Yan-Hong
authors.initials: YH
authors.lastname: Kang
authors.forename: Qi-Huan
authors.initials: QH
authors.lastname: Xu
authors.forename: Qi-Feng
authors.initials: QF
authors.lastname: Xie
mesh_terms: D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D001374:Azacitidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D019175:DNA Methylation; D000077209:Decitabine; D019942:Genes, p16; D056945:Hep G2 Cells; D006801:Humans; D008114:Liver Neoplasms, Experimental / Q000628:therapy*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D034741:RNA, Small Interfering; D015534:Trans-Activators / Q000037:antagonists & inhibitors* / Q000235:genetics; D054334:Viral Regulatory and Accessory Proteins
chemical_list: D000964:Antimetabolites, Antineoplastic; D034741:RNA, Small Interfering; D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein; D000077209:Decitabine; D001374:Azacitidine