title: Expressions of MAGE-A9 and MAGE-A11 in breast cancer and their expression mechanism.
abstract: OBJECTIVE
  The MAGE gene encodes cancer/testis antigens that are selectively expressed in various types of human neoplasms but not in normal tissues other than testis and placenta. However, the expression pattern of MAGE-A9 and MAGE-A11 in breast cancer patients is still unclear. The purpose of our study is to investigate the expression pattern and mechanism of MAGE-A9 and MAGE-A11 in breast cancer patients.
  
  
  METHODS
  The expression of MAGE-A9 and MAGE-A11 was investigated in 60 breast benign diseases specimens, 60 tumor-free breast specimens and 60 breast cancer specimens by RT-PCR, and their correlation with clinicopathological parameters was elucidated. We examined the influence of the DNA methylase inhibitor 5-aza-2'-deoxycytidine (5-aza-CdR) together with the histone deacetylase inhibitor trichostatin A (TSA) on the expression of MAGE-A9 and MAGE-A11 genes in two breast cancer cell lines.
  
  
  RESULTS
  The expression rates of MAGE-A9 and MAGE-A11 in breast cancer specimens were 45 and 66.7%, respectively. MAGE-A9 and MAGE-A11 expression was positively associated with estrogen-receptor (ER) and HER-2 expression (p <0.05). 5-Aza-CdR treatment alone could induce the expression of MAGE-A9 and MAGE-A11 in cell lines that did not express this antigen. TSA treatment alone had no influence on MAGE-A9 and MAGE-A11 gene expression. However, TSA was able synergistically to enhance 5-aza-CdR-mediated MAGE-A transcription (p <0.05).
  
  
  CONCLUSIONS
  Our data show that MAGE-A9 and MAGE-A11 are tumor-specific antigens and not only DNA hypermethylation but also histone deacetylation is responsible for the mechanism underlying MAGE-A9 and MAGE-A11 gene silencing.
authors: Department of Oncology, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei, PR China; Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, PR China.
authors: Shu-Yun
authors: SY
authors: Hou
authors: Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, PR China.
authors: Mei-Xiang
authors: MX
authors: Sang
authors: Department of Breast Cancer Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, PR China.
authors: Cui-Zhi
authors: CZ
authors: Geng
authors: Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, PR China; Center for Disease Control and Prevention of Shijiazhuang, Shijiazhuang, Hebei, PR China.
authors: Wei-Hua
authors: WH
authors: Liu
authors: Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, PR China.
authors: Wei-Hua
authors: WH
authors: Lü
authors: Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, PR China.
authors: Ying-Ying
authors: YY
authors: Xu
authors: Research Center, The Fourth Hospital of Hebei Medical University, Shijiazhuang, Hebei, PR China. Electronic address: baoenshan1962@hotmail.com.
authors: Bao-En
authors: BE
authors: Shan
mesh_terms: D000328:Adult; D000951:Antigens, Neoplasm / Q000235:genetics / Q000378:metabolism*; D001374:Azacitidine / Q000031:analogs & derivatives / Q000494:pharmacology; D001943:Breast Neoplasms / Q000378:metabolism* / Q000473:pathology; D045744:Cell Line, Tumor; D015254:DNA Modification Methylases / Q000037:antagonists & inhibitors; D000077209:Decitabine; D005260:Female; D056572:Histone Deacetylase Inhibitors / Q000494:pharmacology; D006801:Humans; D006877:Hydroxamic Acids / Q000494:pharmacology; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D011960:Receptors, Estrogen / Q000378:metabolism
chemical_list: D000951:Antigens, Neoplasm; D056572:Histone Deacetylase Inhibitors; D006877:Hydroxamic Acids; C110882:MAGEA11 protein, human; C520253:MAGEA9 protein, human; D009363:Neoplasm Proteins; D011960:Receptors, Estrogen; C012589:trichostatin A; D000077209:Decitabine; D015254:DNA Modification Methylases; D001374:Azacitidine
keywords: 5-aza-CdR; Breast cancer; MAGE-A11; MAGE-A9; TSA