title: Low Ki-67 proliferation index is an indicator of poor prognosis in gastric cancer.
abstract: OBJECTIVE
  We designed this study to assess the biologic significance of Ki-67 proliferation index (PI) in gastric cancer.
  
  
  METHODS
  Gastric cancer tissue from 245 patients were immunostained for Ki-67. Ki-67 PI was defined as the percentage of tumor cells positive for Ki-67. In addition, we have previously evaluated the expressions of nine epithelial mesenchymal transition (EMT)-related proteins. The relationship between Ki-67 PI and clinicopathologic parameters, patient survival, and EMT data were sought.
  
  
  RESULTS
  Low Ki-67 PI was correlated with poorly differentiated histology (P = 0.034), an advanced T stage (P < 0.001), and lymph node metastasis (P = 0.011). Also, the low PI group was found to have a significantly worse prognosis than the high PI group (P = 0.003, log-rank test). Multivariate analysis revealed that Ki-67 PI remained as an independent prognostic factor (hazard ratio (95% CI) = 0.670 (0.450-0.999)). Furthermore, greater expressional changes of EMT-related proteins were found to be significantly associated with low Ki-67 PI (P = 0.025).
  
  
  CONCLUSIONS
  These findings suggest that Ki-67 PI is an effective tool for predicting survival in gastric cancer. In addition, we found that an invasive property presented as EMT-related protein expressional changes was inversely correlated with a proliferative activity in gastric cancer.
authors.affiliation: Department of Pathology, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Hee Eun
authors.initials: HE
authors.lastname: Lee
authors.forename: Min A
authors.initials: MA
authors.lastname: Kim
authors.forename: Byung Lan
authors.initials: BL
authors.lastname: Lee
authors.forename: Woo Ho
authors.initials: WH
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D049109:Cell Proliferation; D005260:Female; D006801:Humans; D019394:Ki-67 Antigen / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D011379:Prognosis; D013274:Stomach Neoplasms / Q000401:mortality / Q000473:pathology*
chemical_list: D019394:Ki-67 Antigen