title: The relationship between KRAS gene mutations and HLA class I antigen downregulation in the metastasis of non-small cell lung cancer.
abstract: OBJECTIVE
  To investigate the association between v-Ki-ras2 Kirsten rat sarcoma viral oncogene homologue (KRAS) gene mutations and levels of human leucocyte antigen (HLA) class I antigen in primary lung tumours and metastatic lymph nodes of patients with non-small cell lung cancer (NSCLC).
  
  
  METHODS
  Patients with NSCLC undergoing tumour resection were enrolled. KRAS codon 12 mutations were analysed in normal lung and lymph node tissue, primary lung tumours and metastatic lymph nodes using polymerase chain reaction-restriction fragment length polymorphism analysis. HLA class I antigen immunostaining was examined using flow cytometry.
  
  
  RESULTS
  A total of 65 patients participated in the study. All normal lung tissues had positive HLA class I antigen immunostaining. The majority of primary lung tumours (56/65) and all of the metastatic lymph nodes (31/31) had downregulated HLA class I antigen immunostaining. There was a positive correlation between downregulated HLA class I antigen in primary tumours and metastatic lymph nodes. There was a negative correlation between KRAS codon 12 mutations and the level of HLA class I antigen in primary and metastatic tumours.
  
  
  CONCLUSIONS
  KRAS codon 12 mutations appear to be important in the downregulation of HLA class I antigen in NSCLC. Abnormal activation of the oncogenic KRAS pathway might provide a new treatment target for NSCLC.
authors: Department of Thoracic Surgery, Provincial Hospital Affiliated to Shandong University, Jinan, Shandong Province, China.
authors: Xiao-Peng
authors: XP
authors: He
authors: Fu-Jie
authors: FJ
authors: Song
authors: Xiang-Yan
authors: XY
authors: Liu
authors: Zhou
authors: Z
authors: Wang
authors: Xiang-Xin
authors: XX
authors: Li
authors: Fan-Ying
authors: FY
authors: Liu
authors: Gang
authors: G
authors: Chen
authors: Wen-Peng
authors: WP
authors: Jiang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology; D003062:Codon; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D015395:Histocompatibility Antigens Class I / Q000235:genetics*; D006801:Humans; D008168:Lung / Q000378:metabolism / Q000473:pathology; D008175:Lung Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009154:Mutation; D009367:Neoplasm Staging; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D015398:Signal Transduction; D018631:ras Proteins / Q000235:genetics*
chemical_list: D003062:Codon; D015395:Histocompatibility Antigens Class I; C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins
keywords: HLA class I; Human leucocyte antigen class I; KRAS; metastasis; non-small cell lung cancer; v-Ki-ras2 Kirsten rat sarcoma viral oncogene homologue gene