Expression of cell cycle regulators and growth factor/receptor systems in gastric carcinoma in young adults: Association with Helicobacter pylori infection

We studied the expression of cell cycle regulators and growth factor-recept or systems in gastric carcinoma in young adults and tried to clarify the sp ecific alterations associated with H. pylori. We studied 33 young patients (18-39 years old, mean age 26.4) with gastric carcinoma. The patients were classified into two groups according to the degree of atrophic gastritis. T hen we examined the expression of p53, cripto, cyclin-E, c-met, c-erbB2 and TGF-alpha immunohistochemically and compared the results between the two g roups. The results were compared with 66 sex-, tumor histology-, and depth- matched elder controls (36-86 years old, mean age 64.0). H. pylori was judg ed by Giemsa staining. Seventeen patients had atrophic changes in the corpu s (Group A), while 16 showed superficial gastritis or normal mucosa (Group S). All 17 patients of Group A showed H. pylori infection, while the 3 of t he 16 members of Group S did not have H. pylori. p53 overexpression was obs erved more frequently in Group S (88%) than in Group A (41%, p<0.05). In th e 3 patients without H. pylori infection, all carcinoma specimens showed p5 3 overexpression. Overexpression of cyclin-E was detected in 4 patients fro m Group S. On the other hand, cripto was observed more frequently in Group A than in Group S. No obvious differences were observed in c-erbB2, TGF-alp ha and c-met expression. Overall, p53 overexpression was detected more freq uently in younger than in older patients, whereas cripto expression was les s detected. These results suggest that p53 and cyclin-E may act in an H. py lori-independent or -adjunctive manner for gastric carcinogenesis. Cripto e xpression might be correlated tightly with H. pylori infection.