title: Short hairpin RNA-mediated down-regulation of CENP-A attenuates the aggressive phenotype of lung adenocarcinoma cells.
abstract: BACKGROUND
  Deregulation of centromere protein (CENP)-A, a centromere-specific histone variant, has in the past been linked to cancer initiation and progression. Additionally, our previous work has shown that CENP-A upregulation predicts a poor overall survival in patients with lung adenocarcinoma. The aim of this study was to uncover the biological role of CENP-A in lung adenocarcinoma growth and invasion, including its underlying molecular mechanisms.
  
  
  METHODS
  CENP-A expression was knocked down in human lung adenocarcinoma A549 and PC-9 cells using a short hairpin RNA (shRNA) technology. Subsequently, the effects of this knock down on the proliferation, apoptosis, cell cycle progression, colony formation, migration, invasion and tumorigenicity were assessed. Additionally, Western blot analyses were performed to examine concomitant expression changes in key proteins involved in cell cycle regulation and apoptosis.
  
  
  RESULTS
  We found that shRNA-mediated knock down of CENP-A significantly inhibited the in vitro proliferation and colony formation of A549 and PC-9 cells as compared to control shRNA-transfected cells. In addition, CENP-A down-regulation was found to induce G0/G1 cell cycle arrest and apoptosis, and to inhibit the in vitro migration and invasion of A549 and PC-9 cells. Down-regulation of CENP-A was also found to significantly suppress the in vivo growth of xenografted A549 cells. At the protein level, we found that the expression of p21, p27, CHK2 and Bax was markedly increased and that the expression of CCNG1, Skp2, Cks1 and Bcl-2 was markedly decreased in CENP-A down-regulated cells.
  
  
  CONCLUSIONS
  Based on our results we conclude that down-regulation of CENP-A may attenuate the aggressive phenotype of lung adenocarcinoma cells. As such, CENP-A may serve as a promising therapeutic target for lung adenocarcinoma.
authors.affiliation: Department of Respiratory Medicine, Guangxing Hospital, Hangzhou Hospital of Traditional Chinese Medicine, Zhejiang University of Traditional Chinese Medicine, Hangzhou, People's Republic of China, qingwuzj@126.com.
authors.forename: Qing
authors.initials: Q
authors.lastname: Wu
authors.forename: Yong-Feng
authors.initials: YF
authors.lastname: Chen
authors.forename: Jie
authors.initials: J
authors.lastname: Fu
authors.forename: Qi-Han
authors.initials: QH
authors.lastname: You
authors.forename: Shou-Mei
authors.initials: SM
authors.lastname: Wang
authors.forename: Xue
authors.initials: X
authors.lastname: Huang
authors.forename: Xiao-Jun
authors.initials: XJ
authors.lastname: Feng
authors.forename: Shu-Hui
authors.initials: SH
authors.lastname: Zhang
mesh_terms: D000230:Adenocarcinoma / Q000235:genetics / Q000378:metabolism*; D000077192:Adenocarcinoma of Lung; D017209:Apoptosis / Q000235:genetics / Q000502:physiology; D001324:Autoantigens / Q000235:genetics*; D042846:CDC2-CDC28 Kinases / Q000378:metabolism; D059447:Cell Cycle Checkpoints / Q000235:genetics / Q000502:physiology; D045744:Cell Line, Tumor; D000076247:Centromere Protein A; D064447:Checkpoint Kinase 2 / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics*; D056766:Cyclin G1 / Q000378:metabolism; D050760:Cyclin-Dependent Kinase Inhibitor p27 / Q000378:metabolism; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics / Q000502:physiology; D044786:S-Phase Kinase-Associated Proteins / Q000378:metabolism; D051028:bcl-2-Associated X Protein / Q000378:metabolism; D020741:rho GTP-Binding Proteins / Q000378:metabolism
chemical_list: D001324:Autoantigens; C534702:CCNG1 protein, human; C000619700:CENPA protein, human; C093090:CKS1B protein, human; D000076247:Centromere Protein A; D002868:Chromosomal Proteins, Non-Histone; D056766:Cyclin G1; D019253:Proto-Oncogene Proteins c-bcl-2; D034741:RNA, Small Interfering; D044786:S-Phase Kinase-Associated Proteins; D051028:bcl-2-Associated X Protein; D050760:Cyclin-Dependent Kinase Inhibitor p27; D064447:Checkpoint Kinase 2; C578634:CHEK2 protein, human; D042846:CDC2-CDC28 Kinases; D020741:rho GTP-Binding Proteins