Gene and protein expression of E-cadherin and NCAM markers in non-functioning pituitary adenomas

Non-functioning pituitary adenomas (NFPA) are classified as benign tumors of slow growth, but 40% of them present local invasion, a characteristic of behavior still unpredictable with the use of current tumor markers. This work aims to evaluate the tissue markers E-cadherin and NCAM, which act on cell adhesion, in tumor tissue samples of NFPA and its relationship with the degree of local invasiveness. Gene expression of E-cadherin (CDH1) and NCAM (NCAM1) was assessed by real-time PCR and tissue expression by immunohistochemistry. Fifty-three patients with macroadenomas were submitted to transsphenoidal surgery, presented grade II invasive adenomas in 16 cases (30.2%), grade III in 7 (13.2%) and grade IV in 30 (56.6%). In the immunohistochemistry, one case was negative for E-cadherin, 7 showed weak immunostaining, 17 moderate and 28 strong, whereas for NCAM, 5 showed negative, 28 weakly, 14 moderate and 6 strong. Regarding gene expression, 43.3% showed expression for CDH1 (mean of 2.12) and 50% for NCAM1 (mean of 1.86). There was no significant correlation between the immunohistochemical expression of the markers, as well as the gene expression, the degree of invasiveness and clinical data. The results suggest that E-cadherin and NCAM markers are not directly related to the invasiveness in NFPA.