April - June 2017, Volume 13, Issue 2

Capraru OM, Decaussin-Petrucci M, Joly MO, Borda A, Fanfaret IS, Borson-Chazot F, Selmi-Ruby S

Expression of Menin in the Human Thyroid Gland

Acta Endo (Buc) 2017, 13 (2): 154-160
doi: 10.4183/aeb.2017.154

Introduction. The expression of menin in the thyroid gland has long been debated. Animal models with targeted inactivation of menin in the thyroid gland have shown that its inactivation might play a role in the progression to a more aggressive type of cancer. Human studies are conflicting, some have identified mutations in the MEN1 gene in a subtype of oncocytic thyroid carcinomas, while others have not identified a higher prevalence of thyroid cancer in MEN1 patients. Objective. To analyze the immunohistochemical expression of menin in different types of thyroid carcinomas. Materials and methods. 48 thyroid tumours (12 papillary thyroid carcinomas (PTC), 6 anaplastic thyroid carcinomas (ATC), 12 poorly differentiated thyroid carcinomas (PDTC), 5 medullary thyroid carcinomas (MTC), 5 oncocytic follicular carcinomas (OC), 3 oncocytic adenomas (OA) and 5 goiters (G)) were tested for nuclear expression of menin using an anti-menin antibody. The expression was considered positive, negative or decreased. Results. The expression of menin was positive, identical to normal tissue, in 39 cases (81.25%). The expression was decreased (n=8) or absent (n=1) in 9 tumours (18.75% - 2 PTC, 5 PDTC, 2 OC) accounting for 42% (5/12) of the PDTC and 40% (2/5) of the OC. Conclusions. Our results show that the expression of menin is generally preserved in human thyroid carcinomas, but it can be decreased or absent in certain types of thyroid cancer. Further molecular studies are needed to evaluate to potential of menin protein in tumorigenesis.

Keywords: menin, thyroid carcinoma, immunohistochemistry

Correspondence: Angela Borda, Professor, MD, PhD, Department of Histology, University of Medicine and Pharmacy of Targu-Mures,37 Gheorghe Marinescu Street 540139 Targu Mures, Romania, E-mail: aborda2001@yahoo.com