title: [Regulation mechanism of autophagy-related protein LC3 by c-Jun in methotrexate resistant human choriocarcinoma JEG-3 cells].
abstract: OBJECTIVE
  To explore the regulation mechanism of autophagy- related protein, microtubule- associated protein 1 light chain 3 (LC3), via c-Jun in methotrexate resistant human choriocarcinoma JEG-3 cell lines.
  
  
  METHODS
  Human choriocarcinoma JEG-3 cell lines, and methotrexate resistant choriocarcinoma JEG-3 (JEG-3/MTXR) cell lines were used in our present study. Phosphorylation c-Jun (p-c-Jun) was evaluated after exposure to 0.02 ng/ml methotrexate for 72 hours in both cells by western blot. c-Jun gene was knockdown by small interference RNA (siRNA) in JEG-3/MTXR cells, and LC3 was evaluated by western blot and reverse transcription-PCR. The binding of LC3 promoter with c- Jun protein was detected via chromatin immunoprecipitation assay (ChIP) with or without 0.02 ng/ml methotrexate exposure.
  
  
  RESULTS
  The results showed that p-c-Jun was up-regulated after methotrexate treatment for 72 hours (1.99 ± 0.20, versus 0.20 ± 0.06 at 0 hour; P < 0.05) by western blot analysis in JEG-3/MTXR cell lines. Further investigation demonstrated that c-Jun-siRNA could inhibit the up-regulation of LC3 formation and after methotrexate exposure (LC3 mRNA: 1.24 ± 0.17 versus 3.03 ± 0.43; LC3 protein: 0.52 ± 0.07 verus 1.20 ± 0.15; all P < 0.05). The binding of LC3 promoter by c-Jun protein was up-regulated after methotrexate treatment by the method of ChIP in methotrexate resistant JEG-3/MTXR cells [(2.95 ± 0.35) times].
  
  
  CONCLUSIONS
  Autophagy- related gene LC3 expression regulated by c-Jun protein may be involved in the effect mechanism of the development of methotrexate resistance in choriocarcinoma JEG-3 cells.
authors.affiliation: Department of Obstetries and Gynecology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Shen
authors.affiliation: Department of Obstetries and Gynecology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China. Email: xiangy@pumch.cn.
authors.forename: Yang
authors.initials: Y
authors.lastname: Xiang
authors.affiliation: Department of Obstetries and Gynecology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors.forename: Changji
authors.initials: C
authors.lastname: Xiao
authors.affiliation: Department of Obstetries and Gynecology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D001343:Autophagy / Q000187:drug effects*; D045744:Cell Line, Tumor / Q000187:drug effects*; D002822:Choriocarcinoma; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D008727:Methotrexate / Q000494:pharmacology*; D008869:Microtubule-Associated Proteins / Q000235:genetics* / Q000378:metabolism; D011247:Pregnancy; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D014157:Transcription Factors; D053326:Tumor Necrosis Factor Ligand Superfamily Member 14; D015854:Up-Regulation / Q000187:drug effects; D014594:Uterine Neoplasms
chemical_list: D000964:Antimetabolites, Antineoplastic; C477012:MAP1LC3A protein, human; D008869:Microtubule-Associated Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D014157:Transcription Factors; D053326:Tumor Necrosis Factor Ligand Superfamily Member 14; D008727:Methotrexate