The present case was a 39 year-old-female. Since 1999, gain of body weight and moon face appeared. Since 2002, further gain of body weight, headache, acne, and general fatigue have developed, and she was admitted to our hospital for evaluation. She was finally diagnosed as Cushing's syndrome due to right adrenal tumor. 131I-adosterol scintigraphy showed strong accumulation into right adrenal tumor and abdominal MRI showed 5cm heterogenous right adrenal tumor. Plasma ACTH levels was less than 5.0 pg/ml, serum cortisol level was 46.8μg/dl, and serum DHEAS level was 25600 ng/ml. From these findings, together with rapidly progressive clinical symptoms, this tumor was strongly suspected to be adrenal cancer, and right adrenalectomy was performed. Unexpectedly, pathological diagnosis was benign adrenocortical adenoma. Although cortisol producing adrenocortical adenoma (CPA) is major cause of Cushing's syndrome, the molecular events in the pathogenesis of the tumor have not been well characterized. In the present study, we performed two-dimensional (2-D) gel electrophoresis analysis and quantative image analysis using proteome analysis on typical CPA and the tumor tissue of this case. We isolated several proteins differentially regulated between typical CPA and the tumor tissue of this case by comparing expression profiles of proteins . Our results might provide the basis for more detail studies on the regulation of adrenocortical tumors. Although further studies using the high-throughput MALDI-TOF mass spectrometry are necessary to clarify these issues, the identification of the proteins responsible for the development of adrenocortical tumor might contribute to many aspects of our understanding of adrenocortical tumorigenesis.
