Characterization of neural cell adhesion molecule (NCAM) expression in thyroid follicular cells: Induction by cytokines and over expression in autoimmune glands

Abstract

SUMMARYNCAM (CD56) is a cell surface glyeoprotein of the immunoglobulin superfamily expressed on neuroendocrine and natural killer (NK) eells which has considerable molecular heterogeneity due to differential splicing and post-translational modifications. NCAM has been detected in the thyroid foHicuIar cells (thyrocytes) immunohistoiogically. We report here the molecular form, the modulation by cytokines and the levels of expression in thyroid pathology. By using a panel of MoAbs to NCAM on Western blots from thyrocyte extract we have determined that these cells express the 140-and I80-kD forms of NCAM, Exposure of primary cultures of thyrocytes to interferon-gamma (IFN-7), and even more, to the combination of IFN-7 plus tumour necrosis factor-alpha (TNF-a) induced a clear increase in the expression of NCAM as assessed by FACS analysis. NCAM expression in thyrocytes was assessed by immunofluorescence in 59 surgical specimens of thyroid glands, atid was found increased in 11/17 (64%) of Graves', in 5/25 (20%) of multinodular goitre (MNG) and in occasional adenoma glands. No correlation was found with the expression of HLA class I. class II or the degree of lymphocytic infiltration scored in adjacent sections, but it was often seen in areas infiltrated by macrophagcs. In conclusion, NCAM is an adhesion molecule whose expression is clearly increased in thyrocytes in autoimmune glands, probably as a consequence of exposure to cytokines locally released. Since one of the forms of NCAM expressed by thyrocytes has the capability to generate intracellular signal it may play a role in normal thyroid function. In addition, NCAM may facilitate the recognition of Ihyrocytes by lymphocytes, particularly by NK CD56* lymphocytes.

Silencing of homeobox B9 is associated with down-regulation of CD56 and extrathyroidal extension of tumor in papillary thyroid carcinoma

“…In thyroid gland, CD56 expression has been identified not only in normal thyroid but also in adenomatous hyperplasia, Graves disease, lymphocytic thyroiditis, Hashimoto thyroiditis, and follicular adenoma. In PTC, the expression of CD56 has been found to be markedly reduced, the incidence of reduced CD56 expression in PTC varying from 83.4% to 100% [3][4][5][6][7]24,25]. These variations in the incidence of previous studies might have been caused by difference in the definition of low limit of percentage of positive tumor cells.…”

Diagnostic value of decreased expression of CD56 protein in papillary carcinoma of the thyroid gland

“…21 CD56 is normally present in follicular epithelial cells of thyroid gland. 24 The usefulness of CD56 in differentiating thyroid tumors, especially in making a diagnosis of PC, is receiving increased attention in recent days. 24 The usefulness of CD56 in differentiating thyroid tumors, especially in making a diagnosis of PC, is receiving increased attention in recent days.…”

“…22,23 CD56 expression in the thyroid gland was initially studied in cases of Hashimoto's thyroiditis and Grave's disease and was found to be increased in thyrocytes in autoimmune glands, probably as a consequence of exposure to locally released cytokines. 24 The usefulness of CD56 in differentiating thyroid tumors, especially in making a diagnosis of PC, is receiving increased attention in recent days. 15,16 A recent study investigated CD56 expression in tissue sections of 61 cases of PC and 14 lymph node metastases using immunohistochemical study.…”

Novel RUNX1 isoforms determine the fate of acute myeloid leukemia cells by controlling CD56 expression

“…26,27 Finally, because the regulatory properties of the new RUNX1 splice variants extend beyond CD56 to other RUNX1 target genes ( Figure 2B), the results could be therapeutically relevant for RUNX1-related gene regulation in a broad spectrum of clinical settings, including heart diseases, 9 hematology, 5,28 and autoimmunity. [29][30][31] …”