Nude mice as a model for gonadotropin-induced adrenocortical neoplasia

Certain inbred mice (e.g., DBA/2J, CE) develop sex steroid producing adrenocortical tumors following gonadectomy. This adrenal response is thought to result from an unopposed increase in circulating gonadotropins and/or a decrease in factor(s) of gonadal origin. To differentiate between these two possibilities, we utilized the NU/J strain of nude mice, which are immunologically compromised and therefore permissive to xenografts. One group of female nude mice was gonadectomized, while another group of females received xenografts of CHO cells stably transfected with human chorionic gonadotropin (hCG). After 1-2 months, subcapsular adrenocortical neoplasms containing sex steroid-producing cells were observed in both groups. We conclude that high levels of circulating gonadotropins are sufficient to induce adrenocortical tumorigenesis, even in the presence of intact gonads.