Abstract

The oncogenes, which have been detected in various human solid tumors, transform culture cells, and the level of m-RNA specific for an oncogene increases in the cellular extract of the tumor cells. These findings suggested that oncogene expression was closely related with carcinogenesis. Recently, oncogen products were considered as tumor markers, but it was not confirmed that the relationship between quantitative change of oncogene product and malignant potential of a neoplasm. To evaluate the relationship between the quantitative change of oncogene product and malignant potential, immunohistochemical staining for the ras and myc oncogene products was performed in the sections of papilloma and transitional cell carcinoma of urinary bladder. 1) Positive reaction of c-ras oncogene product was noted along the cell membrane and in the cytoplasm, and c-myc oncogene product in the nucleus, and along the unclear membrane and cell membrane. 2) Tissue expression of c-ras oncogene was homogeneous and strong in the transitional cell carcinoma rather than in papilloma. 3) The ratio of the positive cells with c-ras oncogene product was 35.1% in the papilloma, 79.4% in the grade I, 81.9% in the grade II, 87.6%, in the grade III of transitional cell carcinoma of the urinary bladder. There was a tendency for the ratio to increase with the degree of histological grading. 4) By the immunoperoxidase staining of c-myc oncogene product, the number of the cells showing positive nuclear staining incrased with the tumor grading.

• Keywords: ras and myc oncogene products;transitional cell carcinoma;