Clinical significance of oncogenes and growth factors in ovarian carcinomas

The expression of epidermal growth factor receptor (EGF-R), transforming growth factor alpha (TGF alpha) and the c-myc oncogene was investigated in different specimens of gynecologic carcinomas. EGF specific binding sites were detected in about 50% of adenocarcinomas (ovarian, endometrial, breast) and in over 90% of squamous carcinomas (cervical). There is a positive correlation between the EGF-R binding assay, immunohistochemistry and the relative amounts of mRNA by Northern blotting. TGF alpha was investigated by immunohistochemistry and Northern blotting. TGF alpha immunoreactivity was detected exclusively in the epithelial cells of nonmalignant tissues (skin, cervix, endometrium, large bowel, lung) as well as different ovarian carcinomas. The TGF alpha immunostaining score correlates with the TGF alpha mRNA amounts. The c-myc expression was analyzed by Northern blotting in the specimens of ovarian carcinomas. Whereas, a positive correlation between the c-myc and TGF alpha expression was noticed, no correlation existed between EGF-R and c-myc expression. Progressive disease (PD) of ovarian carcinomas after chemotherapy was mainly noticed in the group of EGF-R- tumors and those with high amounts of c-myc mRNA. EGF-R+ ovarian carcinomas responded significantly better to chemotherapy. However, similar survival times existed between the EGF-R+ and EGF-R- group and the survival times of patients having responded to the treatment was reduced in the EGF-R+ group. This indicates that EGF-R+ and those carcinomas expressing high amounts of c-myc constitute a more aggressive group of ovarian carcinomas.