Pituitary adenomas account for 10-15% of primary intracranial
tumors.
Growth hormone (GH)-secreting
adenomas account for 13% of all
pituitary adenomas and cause
acromegaly. These
tumors can be aggressive, invade surrounding structures and are highly recurrent. The objective of this study was to evaluate
E-cadherin, Slug and
neural cell adhesion molecule (
NCAM) expression in
GH-secreting pituitary adenomas and its relationship to
tumor invasiveness. A cross-sectional study of patients who underwent
hypophysectomy due to
GH-secreting pituitary adenoma from April 2007 to December 2014 was carried out. The medical records were reviewed to collect clinical data. Immediately after surgery,
tumor samples were frozen in liquid
nitrogen and stored in a biofreezer at -80°C for assessment of
E-cadherin 1 (CDH1), SLUG (SNAI2), and
NCAM (NCAM1) by real-time PCR. The samples were fixed in
formalin and embedded in
paraffin for immunohistochemical analysis of
E-cadherin and
NCAM. Thirty-five patients with
acromegaly were included in the study. Of these, 65.7% had invasive
tumors. Immunohistochemically,
E-cadherin was expressed in 96.7% of patients, and
NCAM in 80% of patients. There was no statistically significant relationship between
tumor grade or invasiveness and immunohistochemical expression of these markers. Regarding gene expression, 50% of cases expressed CDH1, none expressed SNAI2, and 53.3% expressed NCAM1. There was no statistically significant relationship between
tumor grade or invasiveness and gene expression of CDH1, SNAI2, and NCAM1. The absence of Slug overexpression and of
E-cadherin and
NCAM suppression suggests that expression of these markers is not associated with
tumor invasiveness in
GH-secreting pituitary adenomas.