title: [The roles of soluble MICA in immune escape of breast tumor].
abstract: OBJECTIVE
  To determine the expression of soluble MICA (sMICA) in serum of patients with breast tumor, and explore the roles of sMICA in immune escape.
  
  
  METHODS
  ELISA was used to examine the sMICA in peripheral blood. The expression of NKG2D were identified by Flow cytometry. The cytotoxicity of NK cells to breast cancer cells was observed with MTT assay.
  
  
  RESULTS
  sMICA was not detected in the serum of healthy person, but(76.8+/-22.3) ng/L in breast benign tumor patients and (205.4+/-71.3) ng/L in breast malignant tumor patients. There was positive correlation between sMICA levels and breast cancer stage. After incubation with sMICA, NK cells got decrease in cytotoxicity from (76.2+/-6.7) % to (48.4+/-4.1) % .The expression of NKG2D and secretion of IFN-gamma decreased at the same time. IL-15 up-regulated the expression of NKG2D on NK cells and increased NK cells cytotoxicity to breast cancer cells.
  
  
  CONCLUSIONS
  sMICA level is positive correlated with breast cancer TNM stage. sMICA reduced the expression of NKG2D, impaired NK-mediated immune surveillance and led to immune escape of breast tumor. IL-15 could up-regulate the expression of NKG2D and increase NK cells cytotoxicity.
authors.affiliation: Department of Immuno-Oncology, Fujian Provincial Tumor Hospital, the Teaching Hospital of Fujian Medical University, Fuzhou 350014, China. yun-bin_ye@yahoo.com
authors.forename: Yun-bin
authors.initials: YB
authors.lastname: Ye
authors.forename: Zhi-feng
authors.initials: ZF
authors.lastname: Zhou
authors.forename: Qiang
authors.initials: Q
authors.lastname: Chen
authors.forename: Jie-yu
authors.initials: JY
authors.lastname: Li
authors.forename: Xia
authors.initials: X
authors.lastname: Chen
authors.forename: Wei-wei
authors.initials: WW
authors.lastname: Huang
mesh_terms: D001943:Breast Neoplasms / Q000097:blood* / Q000235:genetics / Q000276:immunology* / Q000473:pathology; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic; D005260:Female; D015395:Histocompatibility Antigens Class I / Q000097:blood* / Q000737:chemistry / Q000235:genetics / Q000276:immunology; D006801:Humans; D007694:Killer Cells, Natural / Q000276:immunology; D009367:Neoplasm Staging; D012995:Solubility
chemical_list: D015395:Histocompatibility Antigens Class I; C099187:MHC class I-related chain A