title: Clinical significance of soluble major histocompatibility complex class I chain-related a in renal cell carcinoma patients.
abstract: OBJECTIVE
  Major histocompatibility complex class I chain-related A (MICA) is a stress-inducible glycoprotein that can be shed as a soluble protein. This study was conducted to determine the expression of MICA in renal cell carcinoma (RCC) and examine the clinical relevance of soluble MICA (sMICA) in this disease.
  
  
  METHODS
  Immunohistochemistry and real-time PCR analyses were performed to assess the expression of MICA in 48 pairs of RCC and adjacent normal renal tissues. Serum levels of sMICA were measured in 48 RCC patients, 12 patients with benign renal tumors, and 20 healthy individuals. The correlations between sMICA levels and clinicopathological parameters were analyzed and the diagnostic performance of sMICA in RCC was evaluated.
  
  
  RESULTS
  RCCs exhibited elevated expression of MICA compared to adjacent normal tissues. Serum concentrations of sMICA were significantly greater in RCC patients (348.5 ± 32.5 pg/ml) than those with benign disease (289.3 ± 30.4 pg/ml) and healthy controls (168.4 ± 43.2 pg/ml) and significantly correlated with advanced tumor stage, lymph node metastasis, distant metastasis, vascular invasion, and higher histological grade. Using a cut-off point of 250 pg/ml, sMICA demonstrated a specificity and sensitivity of 63.2% and 75.6%, respectively, in distinguishing between RCC and benign renal tumors.
  
  
  CONCLUSIONS
  MICA expression is upregulated in RCC and increased serum sMICA levels predict aggressive tumor behavior. However, the applicability of sMICA alone is limited in distinguishing RCC from benign renal tumors.
authors.affiliation: Department of Urinary Surgery, The 2nd Affiliated Hospital of Harbin Medical University, Harbin, China E-mail : qg_zhu_2012@163.com.
authors.forename: Yu
authors.initials: Y
authors.lastname: Qiu
authors.forename: Ya-Kun
authors.initials: YK
authors.lastname: Zhao
authors.forename: Gang-Jun
authors.initials: GJ
authors.lastname: Yuan
authors.forename: Qing-Guo
authors.initials: QG
authors.lastname: Zhu
mesh_terms: D002292:Carcinoma, Renal Cell / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D016022:Case-Control Studies; D005260:Female; D015395:Histocompatibility Antigens Class I / Q000235:genetics* / Q000378:metabolism*; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D007680:Kidney Neoplasms / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D008207:Lymphatic Metastasis / Q000235:genetics / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015854:Up-Regulation / Q000235:genetics
chemical_list: D015395:Histocompatibility Antigens Class I