Leydig Cell Tumor : STAR Antibody
Steroidogenic acute regulatory protein (STAR) encoded by the STAR gene plays a key role in acute regulation of steroid hormone synthesis. It catalyzes conversion of cholesterol to pregnenolone. STAR is synthesized primarily by steroid-producing cells, including Leydig cells of testis, theca cells and luteal cells of the ovaries, and adrenal cortical cells. STAR is a sensitive and a specific marker of Leydig cell tumor. It is available as a rabbit monoclonal antibody and is useful in differentiating sex cord-stromal tumors from the germ cell tumors of the testis. The image shows strong immunoreactivity for STAR in adrenal tissue. Image courtesy of: Bio Sb Inc.; used with permission.