The Prognostic Significance of Apoptosis-Related Biological Markers in Chinese Gastric Cancer Patients

BACKGROUND AND OBJECTIVE The prognosis varied among the patients with the same stage, therefore there was a need for new prognostic and predictive factors. The aim of this study was to evaluate the relationship of apoptosis-related biological markers such as p53, bcl-2, bax, and c-myc, and clinicopathological features and their prognostic value. METHODS From 1996 to 2007, 4426 patients had undergone curative D2 gastrectomy for gastric cancer at Fudan University Shanghai Cancer Center. Among 501 patients, the expression levels of p53, bcl-2, bax, and c-myc were examined by immunohistochemistry. The prognostic value of biological markers and the correlation between biological markers and other clinicopathological factors were investigated. RESULTS There were 339 males and 162 females with a mean age of 57. The percentages of positive expression of p53, bcl-2, bax, and c-myc were 65%, 22%, 43%, and 58%, respectively. There was a strong correlation between p53, bax, and c-myc expression (P=0.00). There was significant association between bcl-2, and bax expression (P<0.05). p53 expression correlated with histological grade (P=0.01); bcl-2 expression with pathological stage (P=0.00); bax expression with male (P=0.02), histological grade (P=0.01), Borrmann type (P=0.01), tumor location (P=0.00), lymph node metastasis (P=0.03), and pathological stage (P=0.03); c-myc expression with Borrmann type (P=0.00). bcl-2 expression was related with good survival in univariate analysis (P=0.01). Multivariate analysis showed that bcl-2 expression and pathological stage were defined as independent prognostic factors. There were significant differences of overall 5-year survival rates according to bcl-2 expression or not in stage IIB (P=0.03). CONCLUSION The expression of bcl-2 was an independent prognostic factor for patients with gastric cancer; it might be a candidate for the gastric cancer staging system.