title: Receptor-binding cancer antigen expressed on SiSo cells (RCAS1) expression in human benign and malignant thyroid lesions.
abstract: BACKGROUND
  The receptor-binding cancer antigen expressed on SiSo cells (RCAS1) is a human tumor-associated antigen that contributes to tumor progression by enabling cancer cells to evade immune surveillance. The present study aimed to evaluate the clinical significance of RCAS1 expression in human benign and malignant thyroid lesions.
  
  
  METHODS
  RCAS1 protein expression was assessed immunohistochemically on paraffin-embedded thyroid tissues from 121 patients with benign and malignant lesions and was associated with type of thyroid histopathology and tumor stage parameters such as tumor size, lymph node metastases, capsular, lymphatic and vascular invasion.
  
  
  RESULTS
  RCAS1 positivity, overexpression and staining intensity provided a distinct discrimination between benign and malignant thyroid cases (p=0.0006, p=0.0001 and p=0.0001, respectively), as well as between hyperplastic nodule and papillary carcinoma cases (p=0.0229, p=0.0001 and p=0.0001, respectively). RCAS1 positivity, overexpression and staining intensity also provided distinct discrimination between cases with Hashimoto thyroiditis and those with hyperplastic nodule (p=0.0221, p=0.0001 and p=0.0019, respectively). In the subgroup of malignant thyroid lesions, RCAS1 overexpression was significantly associated with large tumor size (p=0.0246), the presence of lymph node metastases (p=0.0351) and capsular invasion (p=0.0397).
  
  
  CONCLUSIONS
  RCAS1 protein may participate in thyroid neoplastic transformation and could be considered as a useful biomarker to improve diagnostic scrutiny.
authors.affiliation: Department of Forensic Medicine and Toxicology, University of Athens, Athens, Greece.
authors.forename: Constantinos
authors.initials: C
authors.lastname: Giaginis
authors.forename: Nikoleta
authors.initials: N
authors.lastname: Demetriou
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Alexandrou
authors.forename: Vasileios
authors.initials: V
authors.lastname: Stolakis
authors.forename: Ioanna
authors.initials: I
authors.lastname: Delladetsima
authors.forename: Jerzy
authors.initials: J
authors.lastname: Klijanienko
authors.forename: Ioannis
authors.initials: I
authors.lastname: Griniatsos
authors.forename: Stamatios
authors.initials: S
authors.lastname: Theocharis
mesh_terms: D000951:Antigens, Neoplasm / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D013194:Staining and Labeling; D013964:Thyroid Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: D000951:Antigens, Neoplasm; C120762:EBAG9 protein, human