title: TNF-α increases the membrane expression of the chemokine receptor CCR6 in thyroid tumor cells, but not in normal thyrocytes: potential role in the metastatic spread of thyroid cancer.
abstract: The chemokine receptor CCR6, selectively bound by CCL20, is involved in the metastatic spread of cancer cells. Tumor necrosis factor-α (TNF-α) displays a complex pro-tumorigenic actions, but it is unknown whether this cytokine could modulate the expression of chemokine receptors in thyroid tumors. The membrane expression of CCR6 was assessed by flow cytometry and immunofluorescence, in primary cultures of normal human thyroid (NHT) cells and in thyroid cancer cell lines (TPC-1 and BCPAP), both in basal conditions and after stimulation with TNF-α. In basal conditions, CCR6+ cells were virtually absent in NHT cells (0.4 ± 0.4 %), while they were detected in TPC-1 (23.6 ± 6.6 %) and in BCPAP (12.9 ± 9.4 %) tumor cells (ANOVA F: 10.534; p < 0.005). The incubation with TNF-α significantly increased the percentage of CCR6+ cells in TPC-1 (23.6 ± 6.6 % vs. 33.1 ± 8.7; p < 0.033) and in BCPAP (12.9 ± 9.4 % vs. 18.1 ± 11.5; p < 0.030), but not in NHT (0.4 ± 0.4 % vs. 0.2 ± 0.3; NS) cells. The magnitude of the TNF-α effect was similar for TPC-1 and BCPAP (∼40 % vs. baseline) cells. TPC-1 cells were characterized by a greater amount of CCR6 per cell as compared with BCPAP cells, both in basal conditions (148.3 ± 33.7 fluorescence intensity vs. 102.5 ± 22.1 p < 0.016) and after TNF-α stimulation (147.8 ± 46.3 fluorescence intensity vs. 95.3 ± 18.5; p < 0.025). Cell migration assays showed that TNF-α treatment significantly increased the rate of migrated cells in those cells in which it also increased the membrane expression of CCR6 (TPC-1 and BCPAP) as compared to basal condition (p < 0.05 for both TPC-1 and BCPAP cells). No effect was observed in NHT cells in which TNF-α stimulation had no effect in terms of CCR6 expression. We first report that TNF-α enhances the expression of CCR6 in thyroid tumor cells, thus providing evidence that TNF-α increases the metastatic potential of thyroid tumors.
authors.affiliation: Unit of Internal Medicine and Endocrinology, Laboratory for Endocrine Disruptors, Fondazione Salvatore Maugeri I.R.C.C.S., Via Maugeri 10, 27100, Pavia, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Coperchini
authors.affiliation: Allergy and Immunology Unit, Fondazione Salvatore Maugeri I.R.C.C.S., Via Maugeri 10, 27100, Pavia, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Pignatti
authors.affiliation: Unit of Internal Medicine and Endocrinology, Laboratory for Endocrine Disruptors, Fondazione Salvatore Maugeri I.R.C.C.S., Via Maugeri 10, 27100, Pavia, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Carbone
authors.affiliation: Molecular Cardiology Unit, Fondazione Salvatore Maugeri I.R.C.C.S., Via Maugeri 10, 27100, Pavia, Italy.
authors.forename: Rossana
authors.initials: R
authors.lastname: Bongianino
authors.affiliation: Department of Molecular Medicine, University of Pavia, Pavia, Italy.|Biotechnology Research Laboratories, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy.
authors.forename: Christian A
authors.initials: CA
authors.lastname: Di Buduo
authors.affiliation: Unit of Internal Medicine and Endocrinology, Laboratory for Endocrine Disruptors, Fondazione Salvatore Maugeri I.R.C.C.S., Via Maugeri 10, 27100, Pavia, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Leporati
authors.affiliation: Unit of Internal Medicine and Endocrinology, Laboratory for Endocrine Disruptors, Fondazione Salvatore Maugeri I.R.C.C.S., Via Maugeri 10, 27100, Pavia, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Croce
authors.affiliation: Unit of Internal Medicine and Endocrinology, Laboratory for Endocrine Disruptors, Fondazione Salvatore Maugeri I.R.C.C.S., Via Maugeri 10, 27100, Pavia, Italy.
authors.forename: Flavia
authors.initials: F
authors.lastname: Magri
authors.affiliation: Department of Molecular Medicine, University of Pavia, Pavia, Italy.|Biotechnology Research Laboratories, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Policlinico San Matteo Foundation, Pavia, Italy.|Department of Biomedical Engineering, Tufts University, Medford, MA, USA.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Balduini
authors.affiliation: Unit of Internal Medicine and Endocrinology, Laboratory for Endocrine Disruptors, Fondazione Salvatore Maugeri I.R.C.C.S., Via Maugeri 10, 27100, Pavia, Italy. luca.chiovato@fsm.it.
authors.forename: Luca
authors.initials: L
authors.lastname: Chiovato
authors.affiliation: Unit of Internal Medicine and Endocrinology, Laboratory for Endocrine Disruptors, Fondazione Salvatore Maugeri I.R.C.C.S., Via Maugeri 10, 27100, Pavia, Italy.
authors.forename: Mario
authors.initials: M
authors.lastname: Rotondi
mesh_terms: D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D054418:Chemokine CCL20 / Q000235:genetics / Q000378:metabolism; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D009361:Neoplasm Invasiveness / Q000235:genetics*; D009362:Neoplasm Metastasis; D054399:Receptors, CCR6 / Q000096:biosynthesis* / Q000235:genetics; D000072637:Thyroid Epithelial Cells / Q000378:metabolism / Q000473:pathology; D013961:Thyroid Gland / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D013964:Thyroid Neoplasms / Q000235:genetics* / Q000473:pathology; D014409:Tumor Necrosis Factor-alpha / Q000008:administration & dosage / Q000235:genetics*
chemical_list: C108355:CCL20 protein, human; C106311:CCR6 protein, human; D054418:Chemokine CCL20; D054399:Receptors, CCR6; D014409:Tumor Necrosis Factor-alpha
keywords: CCR6; Chemokine receptor; Thyroid cancer; Thyroid cancer cell lines; Tumor necrosis factor-α