title: Differential expression of STAT1 and p21 proteins predicts pancreatic cancer progression and prognosis.
abstract: OBJECTIVE
  The transcription factor Stat1 is a member of the family of signal transducers and transcription activators and responds to interferon-γ stimulation. p21 is a p53-responsive gene for cell cycle regulation and mediates Stat1 antitumor activity. The aim of this study was to analyze their expression for prediction of pancreatic cancer progression and prognosis.
  
  
  METHODS
  A total of 100 pancreatic adenocarcinoma tissue specimens were used for construction of a pancreatic cancer tissue microarray for immunohistochemical staining of Stat1 and p21 expression.
  
  
  RESULTS
  Stat1 and p21 proteins were expressed in 88% (88/100) and 82% (82/100) of pancreatic adenocarcinoma tissue specimens, and the expression was inversely associated with tumor differentiation, clinical stages, and lymph node metastasis of pancreatic cancer. There was no association with age, tumor size, or invasion. Moreover, the Kaplan-Meier curve analysis showed that patients with higher Stat1 and p21 expression had better overall survival rates than those with low expression of Stat1 and p21 proteins.
  
  
  CONCLUSIONS
  The loss of expression of Stat1 and p21 proteins corresponded to lymph node metastasis, advanced stage, tumor dedifferentiation, and poor prognosis in patients with pancreatic cancer.
authors.affiliation: From the Department of Surgery, The Second Hospital, Tianjin Medical University, Tianjin, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Sun
authors.forename: Shaoshi
authors.initials: S
authors.lastname: Yang
authors.forename: Ning
authors.initials: N
authors.lastname: Sun
authors.forename: Jianqiu
authors.initials: J
authors.lastname: Chen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D021441:Carcinoma, Pancreatic Ductal / Q000737:chemistry* / Q000401:mortality / Q000556:secondary; D002454:Cell Differentiation; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000032:analysis*; D018450:Disease Progression; D015536:Down-Regulation; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009367:Neoplasm Staging; D010190:Pancreatic Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D012307:Risk Factors; D050794:STAT1 Transcription Factor / Q000032:analysis*; D013997:Time Factors; D046888:Tissue Array Analysis
chemical_list: D014408:Biomarkers, Tumor; C493956:CDKN1A protein, human; D050759:Cyclin-Dependent Kinase Inhibitor p21; D050794:STAT1 Transcription Factor; C494079:STAT1 protein, human