Comparison of the molecular genetics of c-erb-B2 and p53 expression in stomach cancer in Britain and Japan.
McCulloch PG., Ochiai A., O'Dowd GM., Nash JR., Sasako M., Hirohashi S.
BackgroundDifferences in the epidemiology and treatment outcome of stomach cancer have led to the suggestion that in Japan, this disease may be biologically less aggressive than that found in the West. The authors compared p53b and c-erb-B2 expression, trying to identify genetic differences in Japanese compared with Western stomach cancers.MethodsParaffin embedded formalin fixed tissues from 89 British and 89 matched Japanese patients were examined by immunohistochemistry after microwave treatment. Cases were matched for T-stage, year of surgery, and histopathologic grade.ResultsTumors from 48 British and 46 Japanese patients expressed p53, whereas those of 27 British and 28 Japanese patients expressed c-erb-B2. No significant difference in the density or distribution of protein expression was found between the two populations. The distribution of expression between diffuse and intestinal types and the proportion of cases expressing both antigens were similar in the two groups.Conclusionsp53 and c-erb-B2 are expressed in the same way in stomach carcinomas from Japanese and British patients. This study found no evidence of genetic differences in the cancers from the two countries.