title: Relationship between the downregulation of HLA class I antigen and clinicopathological significance in gastric cancer.
abstract: OBJECTIVE
  To discuss the expression of human leukocyte antigen (HLA) class I antigens in gastric cancer and correlate these with pathologic type and TNM stage.
  
  
  METHODS
  The expression of HLA class I antigen was detected by immunohistochemistry in 185 specimens of gastric cancer, 20 gastric cancer specimens with lymphatic metastasis and 22 controls of normal gastric mucosa using four monoclonal antibodies.
  
  
  RESULTS
  The expression of HLA class I antigen (B/C locus) was significantly downregulated in gastric cancer and in lymphatic metastasis than that in normal gastric mucosa (chi2=7.712, P<0.05). The expression of other HLA class I antigens was also downregulated, but the change was slight. There was no relationship between the downregulation of HLA class I antigen and that of beta2m and LMP2. The expression of HLA class I (B/C locus) was statistically correlated with pathologic stage in gastric adenocarcinoma (chi2=4.164, P<0.05).
  
  
  CONCLUSIONS
  The expression of HLA class I antigen (B/C locus) was obviously downregulated in gastric cancer and in lymphatic metastasis. This abnormal expression would provide the tumor cells with a way to avoid immunological recognition.
authors.affiliation: State Education Ministry Laboratory of Development Genes and Human Diseases, Southeast University Medical School, 87 Dingjiaqiao Road, Nanjing 210009, Jiangsu Province, China.
authors.forename: Yu-Qing
authors.initials: YQ
authors.lastname: Shen
authors.forename: Jian-Qiong
authors.initials: JQ
authors.lastname: Zhang
authors.forename: Feng-Qing
authors.initials: FQ
authors.lastname: Miao
authors.forename: Jian-Min
authors.initials: JM
authors.lastname: Zhang
authors.forename: Qin
authors.initials: Q
authors.lastname: Jiang
authors.forename: Hao
authors.initials: H
authors.lastname: Chen
authors.forename: Xiang-Nian
authors.initials: XN
authors.lastname: Shan
authors.forename: Wei
authors.initials: W
authors.lastname: Xie
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005753:Gastric Mucosa / Q000166:cytology / Q000276:immunology; D015972:Gene Expression Regulation, Neoplastic / Q000276:immunology; D006680:HLA Antigens; D015395:Histocompatibility Antigens Class I / Q000235:genetics*; D006801:Humans; D007150:Immunohistochemistry; D008207:Lymphatic Metastasis / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D013274:Stomach Neoplasms / Q000235:genetics* / Q000276:immunology* / Q000473:pathology
chemical_list: D006680:HLA Antigens; D015395:Histocompatibility Antigens Class I