HGH, PRL, and ACTH Gene Expression in Clinically Nonfunctioning Adenomas Detected with Nonisotopic In Situ Hybridization Method.

In situ hybridization (ISH), which can manifest the specific gene expression of anterior pituitary hormones (mRNA), as well as immunohistochemistry (IHC), is needed to clarify the endocrine function of pituitary adenomas. With the aid of nonisotopic ISH, which has several advantages over isotopic ISH, we examined the expression of pituitary hormone mRNAs in 14 clinically nonfunctioning adenomas, which were considered to be a subtype of gonadotroph adenomas. Gene expression of growth hormone (GH; 4/14), prolactin (PRL; 5/14), adrenocorticotroph hormone (ACTH; 4/14), and gonadotropin were detected with our nonisotopic ISH studies. It is suggested from our ISH studies that some clinically nonfunctioning adenomas are composed of hormone (or subunit) producing cells and may be derived from plurihormonal primordial stem cells.