Chronic gastritis patients infected with H. pylori and who had MDM2 SNP309 G/G homozygosity had an increased risk of advanced CRN, particularly high-grade dysplasia including invasive adenocarcinoma.
MDM2 G/G was associated with markedly reduced survival in squamous cell carcinoma (MS of 10.3 versus 49.4 months; adjusted hazard ratio for death, 7.9; 95% confidence interval, 2.4-26.0; P = 0.0007 for G/G versus T/T) but not in adenocarcinoma (SNP-histology interaction P = 0.004).
Resected pancreatic ductal and ampullary adenocarcinomas (n = 50) were analyzed for loss of heterozygosity (LOH) at 15 markers including 5q(APC), 6q(TBSP2), 9p(p16), 10q(PTEN), 12q(MDM2), 17p(TP53), and 18q(DCC/SMAD4).
MDM2 protein was slightly frequently observed in patients with adenocarcinoma, but its presence or absence was not associated with clinicopathological factors such as T-factor, N-factor, stage, tumour size, differentiation or p53 protein status.
The mdm-2-positive/p53-negative immunohistochemical profile was more often seen in adenocarcinomas (P = 0.003), especially in well-differentiated ones (P = 0.02), than in other histologic types of lung cancer, which suggested a p53-independent pathway of mdm-2 overexpression.