title: Downregulation of HLA class I molecules in primary oral squamous cell carcinomas and cell lines.
abstract: OBJECTIVE
  Loss or downregulation of human leukocyte antigen (HLA) class I expression has been reported in a variety of human tumors including oral squamous cell carcinoma (OSCC).
  
  
  METHODS
  Expression of HLA class I molecules were evaluated by immunohistochemistry, flow cytometry, semi-quantitative Western blot and RT-PCR in 43 tissue samples of primary oral squamous cell carcinomas (pOSCC) from Chinese patients and two OSCC cell lines.
  
  
  RESULTS
  HLA class I heavy chain of B/C locus and A locus and beta(2-)microglobulin were obviously lost or downregulated in pOSCC with the percentage of 31, 55 and 35% respectively. The expression of HLA B/C, LMP2, LMP7, LMP10 and PA28beta in OSCC cell lines was also presumably reduced in comparison with normal epithelial cell line.
  
  
  CONCLUSIONS
  These data suggested that the downregulation of HLA class I molecules in OSCC was closely associated with the low-efficient transcription and abnormality of post-transcription regulation of HLA class I genes and antigen presentation-related genes. These results can add more light to the mechanism by which OSCC escape from immunological surveillance.
authors.affiliation: The Key Laboratory of Developmental Genes and Human Disease of Education Ministry, Department of Genetics and Developmental Biology, Southeast University Medical School, Jiangsu Province, China.
authors.forename: Qiusha
authors.initials: Q
authors.lastname: Tang
authors.forename: Jianqiong
authors.initials: J
authors.lastname: Zhang
authors.forename: Bing
authors.initials: B
authors.lastname: Qi
authors.forename: Chuanlai
authors.initials: C
authors.lastname: Shen
authors.forename: Wei
authors.initials: W
authors.lastname: Xie
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000276:immunology*; D045744:Cell Line, Tumor; D015536:Down-Regulation; D015972:Gene Expression Regulation, Neoplastic; D015395:Histocompatibility Antigens Class I / Q000235:genetics* / Q000276:immunology; D006801:Humans; D007157:Immunologic Surveillance / Q000235:genetics*; D007371:Interferon-gamma / Q000494:pharmacology; D009062:Mouth Neoplasms / Q000235:genetics / Q000276:immunology*; D001613:beta 2-Microglobulin / Q000276:immunology
chemical_list: D000998:Antiviral Agents; D015395:Histocompatibility Antigens Class I; D001613:beta 2-Microglobulin; D007371:Interferon-gamma