title: Prognostic value of protein inhibitor of activated STAT3 in breast cancer patients receiving hormone therapy.
abstract: BACKGROUND
  Deregulated signal transducer and activator of transcription 3 (STAT3) signaling has been well documented in certain cancers. Alterations in specific negative regulators, such as protein inhibitor of activated STAT3 (PIAS3), may contribute to cancer development.
  
  
  METHODS
  The expression of total PIAS3 was determined in 100 paired cancerous and non-cancerous breast tissues by immunoblotting and was statistically analyzed along with the clinicopathological characteristics and overall survival of the patients. XTT, immunoblotting, and chromatin immunoprecipitation (Chip) were used to examine the biological effect of PIAS3 in breast cancer cells.
  
  
  RESULTS
  Hormone therapy failed to improve the overall survival in patients presenting with increased PIAS3 expression. Ectopic PIAS3 overexpression increased the proliferation and expression of cyclin D1 in estrogen receptor (ER)-positive MCF-7 and T47D cells, but decreased those in ER-negative MDA-MB-231 and SKBR3 cells. Furthermore, PIAS3 overexpression attenuated cytotoxicity of tamoxifen and increased proliferation and cyclin D1 expression in MCF-7 cells. PIAS3 also decreased the binding of itself on the cyclin D1 promoter and this decreased binding was not affected by tamoxifen.
  
  
  CONCLUSIONS
  PIAS3 may serve as a biomarker for predicting hormone therapy stratification, although it is limited to those breast cancer patients receiving hormone therapy.
authors.affiliation: Department of Pathology, Kaohsiung Municipal Ta-Tung Hospital, No. 68, Zhonghua 3rd Rd, Qianjin Dist, Kaohsiung, 801, R O C, Taiwan.|Department of Pathology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, No.100, Shiquan 1st Rd, Sanmin Dist, Kaohsiung, 807, R O C, Taiwan.
authors.forename: Sheau-Fang
authors.initials: SF
authors.lastname: Yang
authors.affiliation: Department of Surgery, Kaohsiung Municipal Ta-Tung Hospital, No. 68, Zhonghua 3rd Rd, Qianjin Dist, Kaohsiung, 801, R O C, Taiwan.|Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, No. 100, Shiquan 1st Rd, Sanmin Dist, Kaohsiung, 807, R O C, Taiwan.
authors.forename: Ming-Feng
authors.initials: MF
authors.lastname: Hou
authors.affiliation: Department of Surgery, Kaohsiung Municipal Ta-Tung Hospital, No. 68, Zhonghua 3rd Rd, Qianjin Dist, Kaohsiung, 801, R O C, Taiwan.|Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, No. 100, Shiquan 1st Rd, Sanmin Dist, Kaohsiung, 807, R O C, Taiwan.|Department of Laboratory, Kaohsiung Municipal Ta-Tung Hospital, No. 68, Zhonghua 3rd Rd, Qianjin Dist, Kaohsiung, 801, R O C, Taiwan.
authors.forename: Fang-Ming
authors.initials: FM
authors.lastname: Chen
authors.affiliation: Department of Surgery, Kaohsiung Municipal Ta-Tung Hospital, No. 68, Zhonghua 3rd Rd, Qianjin Dist, Kaohsiung, 801, R O C, Taiwan.|Department of Surgery, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, No. 100, Shiquan 1st Rd, Sanmin Dist, Kaohsiung, 807, R O C, Taiwan.
authors.forename: Fu
authors.initials: F
authors.lastname: Ou-Yang
authors.affiliation: School of Pharmacy, College of Pharmacy, China Medical University, No. 91, Hsueh-Shih Road, Taichung, R O C, 40402, Taiwan.|Chinese Medicine Research and Development Center, China Medical University Hospital, No. 2, Yude Road, Taichung, 40447, R O C, Taiwan.
authors.forename: Yang-Chang
authors.initials: YC
authors.lastname: Wu
authors.affiliation: Department of Pathology, Faculty of Medicine, College of Medicine, Kaohsiung Medical University, No.100, Shiquan 1st Rd, Sanmin Dist, Kaohsiung, 807, R O C, Taiwan. cychai@kmu.edu.tw.
authors.forename: Chee-Yin
authors.initials: CY
authors.lastname: Chai
authors.affiliation: Department of Medical Laboratory Sciences and Biotechnology, Fooyin University, No.151, Jinxue Rd, Daliao Dist, Kaohsiung, 831, R O C, Taiwan. glycosamine@yahoo.com.tw.
authors.forename: Yao-Tsung
authors.initials: YT
authors.lastname: Yeh
mesh_terms: D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D049109:Cell Proliferation / Q000235:genetics; D019938:Cyclin D1 / Q000096:biosynthesis; D047628:Estrogen Receptor alpha / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D008207:Lymphatic Metastasis / Q000235:genetics* / Q000473:pathology; D061986:MCF-7 Cells; D018832:Molecular Chaperones / Q000096:biosynthesis* / Q000235:genetics; D050828:Protein Inhibitors of Activated STAT / Q000096:biosynthesis* / Q000235:genetics; D050796:STAT3 Transcription Factor / Q000235:genetics*; D013629:Tamoxifen / Q000008:administration & dosage
chemical_list: D047628:Estrogen Receptor alpha; D018832:Molecular Chaperones; C484745:PIAS3 protein, human; D050828:Protein Inhibitors of Activated STAT; D050796:STAT3 Transcription Factor; C494086:STAT3 protein, human; D013629:Tamoxifen; D019938:Cyclin D1