title: CSF2 Overexpression Is Associated with STAT5 Phosphorylation and Poor Prognosis in Patients with Urothelial Carcinoma.
abstract: BACKGROUND
  Urothelial carcinoma (UC) commonly occurs in the urinary bladder (UB) and rarely in upper the upper urinary tract (UT). Its molecular pathogenesis, however, remains obscure. Though the constitutive phosphorylation of Signal Transducer and Activator of Transcription 5 (STAT5) is an important part of carcinogenesis generally, researchers have not systematically investigated this process specifically in relation to UC. The present study addresses this gap. Through data mining a published transcriptomic database of UBUCs (GSE32894), it identified Colony Stimulating Factor 2 (CSF2) as the stepwise upregulated gene of much significance among those related to the positive regulation of tyrosine phosphorylation of STAT5 (GO:0042523). Since the phosphorylation of STAT5, a key process in the development of UC, is closely associated with CSF2, we then examine CSF2 transcript and protein expression, justifying their association with clinicopathological features and survival in our well-established cohort of patients with UC.
  
  
  METHODS
  Laser capture microdissection in conjunction with real-time qRT-PCR are used to detect CSF2 transcript levels in 24 UBUCs and 6 non-tumor urothelium samples. We then used the H-score method to evaluate the immunohistochemistry in order to determine CSF2 protein expression in 296 UBUCs and 340 UTUCs, respectively. After correlating protein expression status with key clinicopathological features, the prognostic significance of CSF2 protein expression was determined for disease-specific survival (DSS) and metastasis-free survival (MeFS).
  
  
  RESULTS
  We exclusively detected the CSF2 transcript, which was stepwise upregulated in tumor lesions (p=0.010). In both groups of UC we found overexpression of CSF2 significantly related to incremental pT status (UTUC, p=0.011; UBUC, p<0.001), as well as with perineural invasion (UTUC, p=0.002; UBUC, p=0.001). Univariate analysis found a close correlation between CSF2 overexpression and unfavorable prognosis for both DSS (UTUC, p=0.0001; UBUC, p<0.0001) and MeFS (UTUC, p=0.0001; UBUC, p=0.0002). High expression of CSF2 still remained prognostically for DSS (UTUC, p=0.015; UBUC, p=0.004) and MeFS (UTUC, p=0.008; UBUC, p=0.027) in multivariate comparison.
  
  
  CONCLUSIONS
  Our data showed that overexpression of CSF2 was inferred in advanced disease status and poor clinical outcomes for both UTUC and UBUC patients, suggesting that CSF2 may serve as an important prognosticator and a potential therapeutic target of UC.
authors.affiliation: 1. Department of Pathology, Chi Mei Medical Center, Liouying, Tainan, Taiwan;
authors.forename: Yi-Ying
authors.initials: YY
authors.lastname: Lee
authors.affiliation: 2. Department of Urology, Faculty of Medicine, Kaohsiung Medical University;; 3. Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University;; 4. Department of Urology, Kaohsiung Municipal Ta-Tung Hospital;; 5. Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan;
authors.forename: Wen-Jeng
authors.initials: WJ
authors.lastname: Wu
authors.affiliation: 2. Department of Urology, Faculty of Medicine, Kaohsiung Medical University;; 3. Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University;; 5. Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan;
authors.forename: Chun-Nung
authors.initials: CN
authors.lastname: Huang
authors.affiliation: 2. Department of Urology, Faculty of Medicine, Kaohsiung Medical University;; 3. Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University;; 4. Department of Urology, Kaohsiung Municipal Ta-Tung Hospital;; 5. Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan;
authors.forename: Ching-Chia
authors.initials: CC
authors.lastname: Li
authors.affiliation: 2. Department of Urology, Faculty of Medicine, Kaohsiung Medical University;; 3. Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University;; 5. Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan;
authors.forename: Wei-Ming
authors.initials: WM
authors.lastname: Li
authors.affiliation: 2. Department of Urology, Faculty of Medicine, Kaohsiung Medical University;; 3. Department of Urology, Kaohsiung Medical University Hospital, Kaohsiung Medical University;; 5. Center for Stem Cell Research, Kaohsiung Medical University, Kaohsiung, Taiwan;
authors.forename: Bi-Wen
authors.initials: BW
authors.lastname: Yeh
authors.affiliation: 7. Department of Pathology, Kaohsiung Medical University Hospital, Kaohsiung Medical University;
authors.forename: Peir-In
authors.initials: PI
authors.lastname: Liang
authors.affiliation: 8. Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan;
authors.forename: Ting-Feng
authors.initials: TF
authors.lastname: Wu
authors.affiliation: 8. Department of Biotechnology, Southern Taiwan University of Science and Technology, Tainan, Taiwan;; 9. National Institute of Cancer Research, National Health Research Institutes, Tainan, Taiwan;; 10. Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan;; 11. Division of Clinical Pathology, Chi Mei Medical Center, Tainan, Taiwan.
authors.forename: Chien-Feng
authors.initials: CF
authors.lastname: Li
keywords: CSF2; Colony Stimulating Factor 2; upper tract; urinary bladder; urothelial carcinoma.