Objective: To explore the relationship between expressions of apoptosis-related protein Bax, Survivin and p53 and the molecular mechanisms of carcinogenesis and progression of gastric carcinoma. Methods: Tissue microarray and immunohistochemistry were used in this study. Results: The positive rate of Bax protein in gastric cancer (17.7%,17/96) was significantly lower than those in adjacent normal mucosa (51%), intestinal metaplasia (69.2%) and dysplasia (75%), P < 0.01. The positive rate of Survivin expression in gastric cancer (80.6%, 89/98) was significantly higher than that in adjacent normal mucosa (3.9%), P < 0.01. The positive rates of Survivin expression in tumors with different organ metastases (in lymph node metastasis 86.2%, liver 100% and ovarian 100%) were statistically higher than in tumors without metastasis (64.3%), P < 0.05. Bax expression was correlated with Survivin but not with mp53 that was closely related to Survivin expression (P < 0.05) in gastric cancer. Conclusion: The abnormal expressions of Bax, Survivin and mp53 were correlated with the tumorigenesis and progression of gastric carcinoma. P53 and Survivin genes may share the similar mechanism in regulating cell apoptosis, and because of the mutation, p53 gene may lower its down-regulation to Survivin expression.
Yuping Xiao Zhi Lin Lili Mao Dongying Wu Yujia Gao Hongwei Sun Yan Xin
Objective: We investigated the relationship between the expression of Caspase-3, cell proliferation and apoptosis in gastric cancer and their precancerous lesions, to explore the tumorigenesis of the stomach mucosa. Methods: Caspase- 3 expression in 13 normal gastric mucosa, 6 chronic atrophic gastritis (CAG), 31 intestinal metaplasia (IM), 114 dysplasia (DYS) and 20 gastric carcinomas were investigated immunohistochemically. Cell proliferation was evaluated with anti-Ki-67 immunostaining and apoptosis was evaluated using DNA fragmentation in situ by TdT-mediated dUTP biotin nick end labeling (TUNEL) method. Results: Caspase-3 mild-moderately positive expression was observed in most of normal superficial epithelia, its positively polar distribution in normal mucosa, CAG, IM, DYS and gastric carcinomas changed as seen in TUNEL, and so did the positive rate. Caspase-3 protein expression showed significantly positive correlation with the number of apoptotic cells labeled with TUNEL (correlation coefficient r = 0.94; P < 0.01). Ki-67 expression showed a negative but not significant correlation trend with Caspase-3 (correlation coefficient r = –0.23; P > 0.05). Conclusion: Caspase-3 protein expression was up-regulated from CAG to IM and mild-moderate atypical dysplasia, but down-regulated in severe dysplasia and gastric carcinoma, indicating that inactivity or reduced expression of Caspase-3 is closely correlated with carcinogenesis of the stomach mucosa.
China is one of the countries with the highest risk of gastric cancer over the past century,which is still the leading cause of death worldwide.Because metastatic disease of gastric cancer is the most critical impediment to patient survival,it is necessary to further understand the molecular mechanisms of its metastasis.Kiss-1,mapping to chromosome 1q32,is one of these genes regulated at chromosome 6.Kiss-1 expression was discovered to inhibit metastasis in both in vivo melanoma and breast carcinoma models.
