title: Expression of PACAP and PAC1 Receptor in Normal Human Thyroid Gland and in Thyroid Papillary Carcinoma.
abstract: Pituitary adenylate cyclase activating polypeptide (PACAP) belongs to the vasoactive intestinal peptide-secretin-glucagon peptide family, isolated first from ovine hypothalamus. The diverse physiological effects of PACAP are known mainly from animal experiments, including several actions in endocrine glands. Alteration of PACAP expression has been shown in several tumors, but changes in expression of PACAP and its specific PAC1 receptor in human thyroid gland pathologies have not yet been investigated. Therefore, the aim of the present study was to investigate expression of PACAP and its PAC1 receptor in human thyroid papillary carcinoma, the most common endocrine malignant tumor. PACAP and PAC1 receptor expressions were investigated from thyroid gland samples of patients with papillary carcinomas. The staining intensity of follicular epithelial cells and thyroid colloid of tumor tissue was compared to that of tumor-free tissue in the same thyroid glands in a semi-quantitative way. Our results reveal that both PACAP(-like) and PAC1 receptor(-like) immunoreactivities are altered in papillary carcinoma. Stronger PACAP immunoreactivity was observed in active follicles. Colloidal PACAP immunostaining was either lacking or very weak, and more tumorous cells displayed strong apical immunoreactivity. Regarding PAC1 receptor, cells of the normal thyroid tissue showed strong granular expression, which was lacking in the tumor cells. The cytoplasm of tumor cells displayed weak, minimal staining, while in a few tumor cells we observed strong PAC1 receptor expression. This pattern was similar to that observed in the PACAP expression, but fewer in number. In summary, we showed alteration of PACAP and PAC1 receptor expression in human thyroid papillary carcinoma, indicating that PACAP regulation is disturbed in tumorous tissue of the thyroid gland. The exact role of PACAP in thyroid tumor growth should be further explored.
authors: Jakob Henle Institute for Pathology and Neuropathology, Heidelberg, Germany.
authors: Sebastian
authors: S
authors: Bardosi
authors: Jakob Henle Institute for Pathology and Neuropathology, Heidelberg, Germany.
authors: Attila
authors: A
authors: Bardosi
authors: 2nd Department of Internal Medicine, University of Pecs, Pecs, Hungary.
authors: Zsuzsanna
authors: Z
authors: Nagy
authors: Department of Anatomy, University of Pecs, 7624, Szigeti u 12, Pecs, Hungary. dora.reglodi@aok.pte.hu.
authors: Dora
authors: D
authors: Reglodi
mesh_terms: D000328:Adult; D000368:Aged; D002277:Carcinoma / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000235:genetics / Q000378:metabolism*; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I / Q000235:genetics / Q000378:metabolism*; D013961:Thyroid Gland / Q000378:metabolism; D013964:Thyroid Neoplasms / Q000378:metabolism*
chemical_list: D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D051237:Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide, Type I
keywords: PAC1 receptor; PACAP; Papillary carcinoma; Thyroid gland; Tumor