title: Cell cycle inhibitory protein p27 in esophageal squamous cell carcinoma.
abstract: BACKGROUND
  p27 protein is one of the cdk inhibitors which regulates the progression from G1 to S phase of the cell cycle. Reduced expression of p27 protein has been reported to be correlated with poor clinical outcome in patients with various cancers.
  
  
  METHODS
  We performed immunohistochemistry of both p27 and Ki67 in 136 cases of resected human esophageal squamous cell carcinoma, and evaluated the association between p27 immunoreactivity and clinicopathological features including clinical outcome in these patients. We also examined the correlation between labeling index or the percentage of positive tumor cells for p27 and Ki67 in serial tissue sections in these cases.
  
  
  RESULTS
  Cases with invasion of the muscularis propria or adventitia had significantly (p < 0.05) higher p27 LI (65.0 +/- 23.7) than those with invasion limited to mucosa or submucosa and those with carcinoma in situ (58.9 +/- 18.3). There were no significant correlations between p27 and other clinicopathological factors such as sex, age, tumor size, differentiation type, nodal status and histological stage. The cases with p27 LI below 40% tended to have a worse prognosis than those with p27 LI above 40%. There was no significant correlation between Ki67 and p27 LIs.
  
  
  CONCLUSIONS
  Reduced expression of p27 may be correlated with the biological behavior of esophageal squamous cell carcinoma and may play an important role in the early stages of cancer.
authors.affiliation: Department of Surgery, Tohoku University School of Medicine, Sendai, Japan. y-ohhashi@patholo2.med.tohoku
authors.forename: Y
authors.initials: Y
authors.lastname: Ohashi
authors.forename: H
authors.initials: H
authors.lastname: Sasano
authors.forename: H
authors.initials: H
authors.lastname: Yamaki
authors.forename: S
authors.initials: S
authors.lastname: Shizawa
authors.forename: R
authors.initials: R
authors.lastname: Shineha
authors.forename: T
authors.initials: T
authors.lastname: Akaishi
authors.forename: S
authors.initials: S
authors.lastname: Satomi
authors.forename: H
authors.initials: H
authors.lastname: Nagura
mesh_terms: D000328:Adult; D000368:Aged; D002278:Carcinoma in Situ / Q000737:chemistry / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000737:chemistry* / Q000401:mortality / Q000473:pathology; D018797:Cell Cycle Proteins; D002455:Cell Division; D050760:Cyclin-Dependent Kinase Inhibitor p27; D018450:Disease Progression; D004938:Esophageal Neoplasms / Q000737:chemistry* / Q000401:mortality / Q000473:pathology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D007564:Japan / Q000453:epidemiology; D019394:Ki-67 Antigen / Q000032:analysis; D008297:Male; D008869:Microtubule-Associated Proteins / Q000032:analysis* / Q000502:physiology; D008875:Middle Aged; D008940:Mitotic Index; D009092:Mucous Membrane / Q000473:pathology; D009130:Muscle, Smooth / Q000473:pathology; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000032:analysis* / Q000502:physiology; D016019:Survival Analysis; D025521:Tumor Suppressor Proteins
chemical_list: D018797:Cell Cycle Proteins; D019394:Ki-67 Antigen; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D025521:Tumor Suppressor Proteins; D050760:Cyclin-Dependent Kinase Inhibitor p27