Determination of Cell Proliferation Using Mcm2 Antigen and Evaluation of Apoptosis and TGF-[beta]1 Expression in GH-secreting or Clinically Nonfunctioning Pituitary Adenomas

Pituitary adenomas (PA) occasionally show aggressive behavior, with invasion of the surrounding tissues. The identification of markers able to recognize aggressive PA in early stages remains a challenge. We aimed to determine the expression of a new cell proliferation marker, Mcm2, and the presence of apoptosis in PA, and to evaluate the association of clinicopathological features with the apoptotic and proliferative indices. Additionally, the TGF-β1 expression, an inducer of apoptosis, was determined. The proliferative index was determined in GH-secreting or clinically nonfunctioning PA using immunohistochemical (IH) methods for Mcm2 and Ki-67 antigens. The apoptosis was assessed by the TUNEL method and the TGF-β1 expression by IH. A significant positive correlation was found between log Mcm2 index and log Ki-67 index (p