Prognostic significance of p53 protein expression in early gastric cancer.
Mutations of the p53 tumor suppressor gene have been associated with abnormalities in cell cycle regulation, DNA repair and synthesis, apoptosis, and it has been implicated in the prognosis of advanced gastric cancer. The aim of this study was to evaluate the occurrence of p53 gene mutation and its possible prognostic implications in early gastric cancer. In a retrospective study, we studied 80 patients with early gastric cancer treated surgically between 1982 and 2001. Mutation of p53 gene was investigated in surgical gastric specimens by immunohistochemistry, and results were analyzed in relation to gender, age, macroscopic appearance, size and location of tumor, presence of lymph nodes, Lauren's histological type, degree of differentiation, and the 5-year survival. The expression of p53 was more frequent among the intestinal type (p = 0.003), the differentiated (p = 0.007), and the macroscopically elevated tumors (p = 0.038). Nevertheless, the isolated expression of p53 was not associated with the 5-year survival, or with the frequency of lymph node involvement. The degree of differentiation was detected as an independent factor related to the outcome of patients (0.044). Significantly shorter survival time was found in p53-negative compared with p53-positive patients, when considering the degree of differentiation of tumors, as assessed by Cox regression analysis (0.049). The association of p53 with the intestinal type, the degree of differentiation and morphological characteristics, may reflect the involvement of chronic inflammatory process underlying early gastric cancer. In this population sample, the expression of p53 alone has no prognostic value for early gastric cancer. However, the significant difference in p53 expression between subgroups of degree of differentiation of tumors can influence post-operative outcome of patients and may be related to possible distinct etiopathogenic subtypes.
Departamento de Clínica Médica, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Andrea Rodrigues
AR
Gonçalves
Antonio Jose Vasconcellos
AJ
Carneiro
Ivanir
I
Martins
Paulo Antonio Silvestre
PA
de Faria
Maria Aparecida
MA
Ferreira
Eduardo Linhares Riello
EL
de Mello
Homero Soares
HS
Fogaça
Celeste Carvalho Siqueira
CC
Elia
Heitor Siffert Pereira
HS
de Souza
D000230:Adenocarcinoma / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D014408:Biomarkers, Tumor / Q000032:analysis*; D002454:Cell Differentiation; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D013274:Stomach Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D016159:Tumor Suppressor Protein p53 / Q000096:biosynthesis*
D014408:Biomarkers, Tumor; C495901:TP53 protein, human; D016159:Tumor Suppressor Protein p53