Abstract

To search biologic characteristics of gastric carcinoma, one of the most common cancer in Korea, the author examined the alterations in DNA level and the expression of Ha-ras gene and c-myc gene in 20 primary tumors. Amplification of c-Ha-ras DNA was detected in 4(40%) of 10 patients who showed histologic subtype of relatively differentiated adenocarcinoma, but rearrangement of c-Ha-ras DNA was absent. Neither augumentation nor deletion of the c-myc DNA was observed. Higher expression of the ras p21 in tumor cells was noted in more differentiated tumor cells rather than poorly differentiated cases. One mucinous carcinoma, two signet ring cell carcinomas and one papillary carcinoma did not disclose expression of p21. The expressions of c-myc oncogene product were variable and were not correspond to the expressions of ras p21. A tendency that poorly differentiated tumor cells had higher expression of c-myc oncogene was suggested.

• Keywords: Gastric carcinoma;Ha-ras;c-myc;DNA amplification;Immunohistochemistry;