title: Clinicopathological correlation and prognostic significance of protein kinase cα overexpression in human gastric carcinoma.
abstract: OBJECTIVE
  This study investigated the PKCα protein expression in gastric carcinoma, and correlated it with clinicopathological parameters. The prognostic significance of PKCα protein expression in gastric carcinoma was analyzed.
  
  
  METHODS
  Quantitative real-time PCR test was applied to compare the PKCα mRNA expression in tumorous and nontumorous tissues of gastric carcinoma in ten randomly selected cases. Then PKCα protein expression was evaluated in 215 cases of gastric carcinoma using immunohistochemical method. The immunoreactivity was scored semiquantitatively as: 0 = absent; 1 = weak; 2 = moderate; and 3 = strong. All cases were further classified into two groups, namely PKCα overexpression group with score 2 or 3, and non-overexpression group with score 0 or 1. The PKCα protein expression was correlated with clinicopathological parameters. Survival analysis was performed to determine the prognostic significance of PKCα protein expression in patients with gastric carcinoma.
  
  
  RESULTS
  PKCα mRNA expression was upregulated in all ten cases of gastric carcinoma via quantitative real-time PCR test. In immunohistochemical study, eighty-eight out of 215 cases (41%) of gastric carcinoma revealed PKCα protein overexpression, which was statistically correlated with age (P = 0.0073), histologic type (P<0.0001), tumor differentiation (P = 0.0110), depth of invasion (P = 0.0003), angiolymphatic invasion (P = 0.0373), pathologic stage (P = 0.0047), and distant metastasis (P = 0.0048). We found no significant difference in overall and disease free survival rates between PKCα overexpression and non-overexpression groups (P = 0.0680 and 0.0587). However, PKCα protein overexpression emerged as a significant independent prognostic factor in multivariate Cox regression analysis (hazard ratio 0.632, P = 0.0415).
  
  
  CONCLUSIONS
  PKCα protein is upregulated in gastric carcinoma. PKCα protein expression is statistically correlated with age, histologic type, tumor differentiation, depth of invasion, angiolymphatic invasion, pathologic stage, and distant metastasis. The PKCα protein overexpression in patients with gastric carcinoma is a significant independent prognostic factor in multivariate Cox regression analysis.
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Mackay Memorial Hospital, Taipei, Taiwan.
authors.forename: Shee-Chan
authors.initials: SC
authors.lastname: Lin
authors.forename: Wei-Yu
authors.initials: WY
authors.lastname: Chen
authors.forename: Kai-Yuan
authors.initials: KY
authors.lastname: Lin
authors.forename: Sheng-Hsuan
authors.initials: SH
authors.lastname: Chen
authors.forename: Chun-Chao
authors.initials: CC
authors.lastname: Chang
authors.forename: Sey-En
authors.initials: SE
authors.lastname: Lin
authors.forename: Chia-Lang
authors.initials: CL
authors.lastname: Fang
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D002277:Carcinoma / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology*; D005260:Female; D015870:Gene Expression; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D051571:Protein Kinase C-alpha / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013274:Stomach Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000473:pathology*
chemical_list: D012333:RNA, Messenger; D051571:Protein Kinase C-alpha