title: [Inhibition of transcription and expression of X gene by lamivudine].
abstract: OBJECTIVE
  The X protein of the hepatitis virus B plays an important role in the development of hepatocellular carcinoma (HCC). In this experiment we studied the effects of lamivudine on replication, transcription and expression of the X gene.
  
  
  METHODS
  The replication of transfected X gene was measured by polymerase chain reaction. The mRNA of transfected X gene was analyzed by reverse transcriptase polymerase chain reaction. The expression of X protein was detected by biosensor. Moreover, we studied if these effects changed in a dose and time dependent manner.
  
  
  RESULTS
  The OD data of purpose band reflected the replication of X gene for control and lamivudine groups were 151.4+/-3.5 and 144.0+/-11.4, respectively. The transcription of mRNA for X gene could be inhibited by lamivudine at a concentration of 4.36 x 10(-4) mol/L for 24 h. The OD data of purpose band for control and treatment groups (16 h) were 243.9+/-9.0 and 133.2+/-7.8. The inhibition was enhanced with the increase of lamivudine concentration and reacting time. The expression of the X protein in HepG2x cells was suppressed by lamivudine at a concentration of 4.36 x 10(-4) mol/L for 16 hours. The resonance unit for expression of the X protein decreased from 353.3+/-15.9 to 252.3+/-18.8.
  
  
  CONCLUSIONS
  Although the replication of transfected X gene of HepG2x cells is not influenced by lamivudine, it may significantly inhibit the transcription and expression of the X protein.
authors.affiliation: Department of Reproduction Physiology, Department of Reproductive Medicine, Chongqing Medical University, Chongqing 400016, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Xie
authors.forename: Qi
authors.initials: Q
authors.lastname: Liu
authors.forename: Chun-Hui
authors.initials: CH
authors.lastname: Wang
authors.forename: Cheng-Wei
authors.initials: CW
authors.lastname: Tang
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000188:drug therapy / Q000821:virology*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006515:Hepatitis B virus / Q000235:genetics*; D006801:Humans; D019259:Lamivudine / Q000627:therapeutic use*; D008113:Liver Neoplasms / Q000188:drug therapy / Q000821:virology*; D008297:Male; D018894:Reverse Transcriptase Inhibitors / Q000627:therapeutic use; D015534:Trans-Activators / Q000096:biosynthesis* / Q000235:genetics; D014158:Transcription, Genetic / Q000187:drug effects; D054334:Viral Regulatory and Accessory Proteins
chemical_list: D018894:Reverse Transcriptase Inhibitors; D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein; D019259:Lamivudine