title: Serum soluble ST2 is associated with ER-positive breast cancer.
abstract: BACKGROUND
  ST2, a member of the interleukin (IL)-1receptor family, regulates Th1/Th2 immune responses in autoimmune and inflammatory conditions. However, the role of ST2 signaling in tumor growth and metastasis of breast cancers has not been investigated. This study investigated the possible role of soluble ST2 (sST2) in breast cancer.
  
  
  METHODS
  The serum levels of IL-33, sST2, and vascular endothelial growth factor (VEGF) in 150 breast cancer patients and 90 healthy women were measured by enzyme-linked immunosorbent assay. Estrogen receptor(ER), progesterone receptor, human epithelial receptor (HER)-2, and cell cycle regulated protein Ki-67 were measured. Clinical stage, tumor size, lymph node metastasis, and histological type were also recorded.
  
  
  RESULTS
  The serum levels of sST2, IL-33, and VEGF were significantly higher in breast cancer patients than in the control group (P < 0.05, each). Serum sST2 levels in ER-positive breast cancer patients were significantly associated with age, histological type, clinical stage, tumor size, and Ki-67 status (P < 0.05, each). Moreover, the serum levels of IL-33 and sST2 in breast cancers significantly correlated with VEGF levels (IL-33: r = 0.375, P < 0.0001; sST2: r = 0.164, P = 0.045). Serum levels of sST2, IL-33, and VEGF decreased after modified radical mastectomy in ER-positive breast cancers. Serum levels of IL-33, sST2, and VEGF and clinicopathological factors were not significantly correlated with disease-free survival and overall survival of ER-positive breast cancer women during follow-up.
  
  
  CONCLUSIONS
  Serum sST2 levels in ER-positive breast cancer patients are significantly associated with factors that indicate poor prognosis.
authors.forename: Da-Peng
authors.initials: DP
authors.lastname: Lu
authors.forename: Xiang-Yu
authors.initials: XY
authors.lastname: Zhou
authors.forename: Lu-Tian
authors.initials: LT
authors.lastname: Yao
authors.forename: Cai-Gang
authors.initials: CG
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Ma
authors.forename: Feng
authors.initials: F
authors.lastname: Jin
authors.affiliation: Department of Breast Surgery, First Affiliated Hospital of China Medical University, 155 Nanjing North Street, Heping District, Shenyang 110001, PR China. wuyunfei860516@163.com.
authors.forename: Yun-Fei
authors.initials: YF
authors.lastname: Wu
mesh_terms: D000328:Adult; D014408:Biomarkers, Tumor / Q000378:metabolism; D001943:Breast Neoplasms / Q000097:blood* / Q000175:diagnosis / Q000473:pathology*; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D000072179:Interleukin-1 Receptor-Like 1 Protein; D000067596:Interleukin-33; D007378:Interleukins / Q000097:blood; D008875:Middle Aged; D011446:Prospective Studies; D011956:Receptors, Cell Surface / Q000097:blood*; D011960:Receptors, Estrogen / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000097:blood
chemical_list: D014408:Biomarkers, Tumor; C079241:IL1RL1 protein, human; C506536:IL33 protein, human; D000072179:Interleukin-1 Receptor-Like 1 Protein; D000067596:Interleukin-33; D007378:Interleukins; D011956:Receptors, Cell Surface; D011960:Receptors, Estrogen; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A