Noninvasive encapsulated follicular variants of papillary thyroid carcinomas have been recently reclassified as noninvasive follicular thyroid neoplasms with papillary-like nuclear features (NIFTPs). NIFTPs exhibit a behavior that is very close to that of follicular adenomas but different from the infiltrative and invasive follicular variants of papillary thyroid carcinomas (FVPTCs). The importance of miRNAs to carcinogenesis has been reported in recent years. miRNAs seem to be promising diagnostic and prognostic molecular markers for thyroid cancer, and the combination of miRNA expression and mutational status might improve cytological diagnosis. The aim of the present study was to evaluate the miRNA expression profile in wild-type, RAS - or BRAF-mutated NIFTPs, infiltrative and invasive FVPTCs, and follicular adenomas using the nCounter miRNA Expression assay (NanoString Technologies). To identify the significant Kyoto Encyclopedia of Genes and Genomes (KEGG) molecular pathways associated with deregulated miRNAs, we used the union of pathways option in DNA Intelligent Analysis (DIANA) miRPath software. We have shown that the miRNA expression profiles of wild-type and mutated NIFTPs could be different. The expression profile of wild-type NIFTPs seems comparable to that of follicular adenomas, whereas mutated NIFTPs have an expression profile similar to that of infiltrative and invasive FVPTCs. The upregulation of 4 miRNAs (miR-221-5p, miR-221-3p, miR-222-3p, miR-146b-5p) and the downregulation of 8 miRNAs (miR-181a-3p, miR-28-5p, miR-363-3p, miR-342-3p, miR-1285-5p, miR-152-3p, miR-25-3p, miR-30e-3) in mutated NIFTPs compared to wild-type ones suggest a potential invasive-like phenotype by deregulating the specific pathways involved in cell adhesion and cell migration (Hippo signaling pathway, ECM-receptor interaction, adherens junction, regulation of actin cytoskeleton, fatty acid biosynthesis and metabolism).
Maria Denaro, Clara Ugolini, Anello Marcello Poma, Nicla Borrelli, Gabriele Materazzi, Paolo Piaggi, Massimo Chiarugi, Paolo Miccoli, Paolo Vitti and Fulvio Basolo
Paolo Miccoli, Michele N Minuto, Clara Ugolini, Eleonora Molinaro, Fulvio Basolo, Piero Berti, Aldo Pinchera and Rossella Elisei
Total thyroidectomy and central neck dissection are the procedures of choice in patients affected with medullary thyroid cancer. It is known that a medullary thyroid cancer with node metastases can be rarely cured, and therefore the utility of a modified radical neck dissection in the absence of suspicious node metastases still needs further evidence. The study aims to verify whether other epidemiological and pathological parameters could affect the prognosis of medullary thyroid cancer patients. We prospectively studied 70 medullary thyroid cancer patients consecutively operated on (from 2000 to 2004) at the same institution and analysed by the same pathologists. All patients underwent total thyroidectomy and central lymphadenectomy. In 27 cases, the ipsilateral (n=19) or bilateral (n=8) modified radical neck dissection was performed in the presence of suspicious lateral neck node metastases. After surgical treatment, basal and stimulated serum calcitonins (Cts) were measured in all patients. Follow-up ranged between 1 and 4 years. Patients were considered ‘cured’ when stimulated Ct was undetectable. Age, sex, tumour size, tumour capsule, multicentricity, nodes in the central neck and mean number of positive nodes were analysed in ‘cured’ and ‘not-cured’ patients. The presence of node metastases in the central compartment was significantly correlated with the outcome of the patients, being present in 9 and 72% of cured and not-cured patients respectively (P<0.000001). Tumour size was also significantly correlated with the outcome of the disease (P<0.00006). The presence of the tumour capsule correlated with better prognosis (P=0.0005) and absence of node metastases (P=0.0080). By multivariate analysis, the presence of node metastasis remained the most significant variable affecting the outcome of the disease (P=0.000014). Our results show that the outcome of encapsulated cancer is significantly better regardless of tumour size and node metastases. Although the early diagnosis and the extensive surgical treatment may favour the good outcome of medullary thyroid cancer, they do not always guarantee the definitive cure of the disease, being the capsular infiltration an independent bad prognostic factor.
Cristina Romei, Raffaele Ciampi, Pinuccia Faviana, Laura Agate, Eleonora Molinaro, Valeria Bottici, Fulvio Basolo, Paolo Miccoli, Furio Pacini, Aldo Pinchera and Rossella Elisei
A low sodium iodide symporter (NIS) expression has been shown in papillary thyroid carcinomas (PTCs) harboring the BRAFV600E mutation. In the present study, we analyzed the mRNA expression of thyroid differentiation genes, glucose transporter (GLUT)-1 and GLUT-3, in 78 PTCs according to the presence of BRAFV600E or RET/PTC rearrangements. We found BRAFV600E and RET/PTC rearrangements in 35.8 and 19.4% of PTCs respectively. The mRNA expression of NIS and thyroperoxidase (TPO) genes were significantly lower (P<0.0001 and P=0.004 respectively) in BRAFV600E-positive PTC with respect to non-mutated samples. In support of this result, immunohistochemistry showed that the percentage of NIS-positive cells was significantly lower (P=0.005) in BRAFV600E-mutated PTC (mean 53.5%) than in negative cases (mean 72.6%). In contrast, no difference either in NIS or in any other thyroid differentiation genes' mRNA expression was found in PTC with or without RET/PTC rearrangements. When GLUT-1 and GLUT-3 mRNA expression was considered, no correlation was found either in BRAFV600E- nor in RET/PTC-mutated cases. In conclusion, this study confirmed the presence of a genetic alteration of BRAF and/or RET oncogenes in 64% of PTC cases and revealed a significant correlation of BRAFV600E mutation with a lower expression of both NIS and TPO. This latter finding could indicate that an early dedifferentiation process is present at the molecular level in BRAFV600E-mutated PTC, thus suggesting that the previously demonstrated poor prognostic significance of BRAFV600E mutation could be related to the dedifferentiation process more than to a more advanced stage at diagnosis.
Alessandro Antonelli, Silvia Martina Ferrari, Poupak Fallahi, Silvia Frascerra, Simona Piaggi, Stefania Gelmini, Cristiana Lupi, Michele Minuto, Piero Berti, Salvatore Benvenga, Fulvio Basolo, Claudio Orlando and Paolo Miccoli
In papillary thyroid carcinomas (PTCs), oncogenes activate a transcriptional program including the upregulation of CXCL10 chemokine, which stimulates proliferation and invasion. Furthermore, peroxisome proliferator-activated receptor-γ (PPARγ) activators thiazolidinediones (TZDs) modulate CXCL10 secretion in normal thyroid follicular cells (TFC), and inhibit PTC growth. Until now, no study has evaluated the effect of cytokines on CXCL10 secretion in PTCs, nor the effect of PPARγ activation. The combined effects of interferon γ (IFNγ) and tumor necrosis factor α (TNFα) stimulation on CXCL10 secretion in primary cells from PTCs and TFC were tested. Furthermore, the effect of PPARγ activation by TZDs, on CXCL10 secretion and proliferation in these cell types was studied. In primary cultures of TFC and PTCs CXCL10 production was absent under basal conditions; a similar dose-dependent secretion of CXCL10 was induced by IFNγ in both cell types. TNFα alone induced a slight but significant CXCL10 secretion only in PTCs. The stimulation with IFNγ+TNFα induced a synergistic CXCL10 release in both cell types; however, a secretion more than ten times higher was induced in PTCs. Treatment of TFC with TZDs dose-dependently suppressed IFNγ+TNFα-induced CXCL10 release, while TZDs stimulated CXCL10 secretion in PTCs. A significant antiproliferative effect by TZDs was observed only in PTCs. In conclusion, a dysregulation of CXCL10 secretion has been shown in PTCs. In fact, a CXCL10 secretion more than ten times higher has been induced by IFNγ+TNFα in PTCs with respect to TFC. Moreover, TZDs inhibited CXCL10 secretion in TFC and stimulated it in PTCs. The effect of TZDs on CXCL10 was unrelated to the significant antiproliferative effect in PTCs.