Molecular Signature of Indeterminate Thyroid Lesions: Current Methods to Improve Fine Needle Aspiration Cytology (FNAC) Diagnosis.

Fine needle aspiration cytology (FNAC) represents the gold standard for determining the nature of thyroid nodules. It is a reliable method with good sensitivity and specificity. However, indeterminate lesions remain a diagnostic challenge and researchers have contributed molecular markers to search for in cytological material to refine FNAC diagnosis and avoid unnecessary surgeries. Nowadays, several "home-made" methods as well as commercial tests are available to investigate the molecular signature of an aspirate. Moreover, other markers (i.e., microRNA, and circulating tumor cells) have been proposed to discriminate benign from malignant thyroid lesions. Here, we review the literature and provide data from our laboratory on mutational analysis of FNAC material and circulating microRNA expression obtained in the last 6 years.

Preliminary results from whole-genome expression analysis in patients with secondary adrenal insufficiency treated with modified-release hydrocortisone.

PURPOSE: Conventional (CONV) treatment of adrenal insufficiency (AI) is associated with risk of overtreatment: glyco-metabolic impairment, bone loss, and reduced quality of life. Recent findings suggest that modified-release hydrocortisone (MOD) may restore a more physiological cortisol profile. Our aims were: (1) to compare the gene expression profile of peripheral blood mononuclear cells derived from patients, with secondary AI (SAI), under CONV (cortisone acetate or hydrocortisone) or MOD versus healthy controls; and (2) to evaluate MOD effects on serum cortisol profile, glucose, lipid, bone, and clinical parameters. METHODS: Thirteen patients with SAI were switched from CONV to MOD at equivalent dose. Area under curve (AUC) of both formulations was calculated in six patients. Clinical, metabolic and bone parameters were measured at baseline and 3 months after MOD in all patients. In six patients and six age- and sex-matched healthy controls, a whole-genome expression analysis was performed at baseline, 1 month, and 3 months after MOD. RESULTS: (1) The number of genes differentially expressed (n = 235; mainly involved in immune response and metabolism) in SAI patients compared to controls progressively and significantly decreased switching from CONV to MOD (n = 78 at 3 months). (2) Under MOD: AUC of cortisol exposure tended to be smaller and cortisol levels showed a more physiological profile; no significant changes of clinical, metabolic and bone parameters were observed, likely due to the short follow-up, but triglycerides tended slightly to increase. CONCLUSIONS: MOD may restore a normal gene expression profile as soon as 1 month after switching from CONV.

Diagnostic Value of Circulating microRNA-95 and -190 in the Differential Diagnosis of Thyroid Nodules: A Validation Study in 1000 Consecutive Patients.

BACKGROUND: It has recently been demonstrated that the combination of miRNA-190 and -95 (expressed as probability of malignant risk: pmiRNA) in the serum of Caucasian patients with thyroid nodular disease allows the identification of nodules at high risk of malignancy with great accuracy. The present study aimed to validate these results in a larger cohort of patients. MATERIALS AND METHODS: This study prospectively analyzed 1000 patients. Cytological diagnosis was available in 982/1000 (98.2%) and histological diagnosis in 445/1000 (44.5%). The expression levels of circulating miRNA-190 and -95 were determined by real time polymerase chain reaction with the 2-ΔΔct method. The diagnostic performance (sensitivity, specificity, and accuracy) of fine-needle aspiration cytology (FNAC), pmiRNA, and a combination of the two methods was correlated with the cytological and histological diagnoses. RESULTS: The combination of pmiRNA and FNAC significantly increased the sensitivity (96.3%) with respect to each method alone (88.9% for FNAC and 89.6% for pmiRNA) by reducing the rate of false-negative results from 18 for FNAC and 17 for pmiRNA to only five. In patients in whom FNAC was not performed (n = 14) or in those with inadequate (n = 18) or indeterminate (n = 72) lesions submitted to surgery, pmiRNA correctly identified 90.8% of patients with benign disease and 74.3% of patients with cancer. CONCLUSIONS: These results confirm that a combination of serum expression levels of miRNA-95 and -190 is an accurate and noninvasive tool for the differential diagnosis of thyroid nodules in the Italian population.

IFNγ-Inducible Chemokines Decrease upon Selenomethionine Supplementation in Women with Euthyroid Autoimmune Thyroiditis: Comparison between Two Doses of Selenomethionine (80 or 160 µg) versus Placebo.

BACKGROUND: Several studies have suggested that selenium may influence the natural history of autoimmune thyroiditis (AIT). Recently, IFNγ-inducible chemokines (CXCL-9, -10 and -11) were shown to be elevated in AIT patients. OBJECTIVE: This prospective, randomized, controlled study was conducted to evaluate the effect of two doses of selenomethionine (Semet; 80 or 160 µg/day) versus placebo in euthyroid women with AIT, in terms of reduction of anti-thyroid antibodies, CXCL-9, -10 and -11 and improvement of thyroid echogenicity, over 12 months. PATIENTS AND METHODS: Sixty patients, aged 21-65 years, were equally randomized into 3 groups: placebo, 80 µg/day of Semet (80-Semet) or 160 µg/day of Semet (160-Semet). RESULTS: Anti-thyroperoxidase antibody (TPOAb) levels remained unaffected by Semet supplementation; anti-thyroglobulin antibody levels showed a significant reduction in the 160-Semet and the placebo group at 12 months. No significant change in thyroid echogenicity, thyroid volume and quality of life was observed within and between the groups. Subclinical hypothyroidism was diagnosed in 2 patients of the placebo group versus 1 patient in each Semet group. Serum CXCL-9 and -10 were significantly reduced in both Semet groups at 6 and 12 months, while they remained unchanged or increased in the placebo group. CXCL-11, TNFα and IFNγ showed a transient decrease at 6 months in both Semet groups but returned nearly to the basal levels at 12 months. CONCLUSIONS: Semet supplementation had no positive effect on thyroid echogenicity or TPOAb in our patients. However, we observed a Semet-dependent downregulation of the IFNγ-inducible chemokines, especially CXCL-9 and -10, which may serve as helpful biomarkers in future selenium supplementation trials.

Circulating miRNA95 and miRNA190 are sensitive markers for the differential diagnosis of thyroid nodules in a Caucasian population.

CONTEXT: MicroRNA (miRNAs) are nonprotein-encoding RNAs that regulate gene expression and enable the distinction of benign from malignant tissues in human cancers. OBJECTIVE: We investigated the role of miRNA circulating in the blood for the differential diagnosis of thyroid nodules. SETTING AND DESIGN: miRNA profiling was assessed by TaqMan Array Human MicroRNA A Cards v2.0 in pooled sera from 12 healthy subjects (HS), 12 nodular goiters (NG), and 12 patients with papillary thyroid cancer (PTC) (cohort 1). From this analysis, we selected eight miRNAs that were validated in individual samples (same of cohort 1) by qRT-PCR. Four miRNAs were confirmed differentially expressed in PTC and were analyzed in a larger second cohort. RESULTS: The profiling analysis revealed eight miRNAs (miRNA579, -95, -29b, 5-01-3p, -548d-5p down-regulated, and miR190, -362-3p, -518a-5p up-regulated) which differ in PTC compared with NG and HS. After the validation in individual samples, we confirmed as differentially expressed miRNA579, -95, -29b, and miRNA190. These miRNAs were further validated in a second cohort of sera from 79 PTC, 80 NG, and 41 HS. MiRNA95 had a sensitivity of 94.9%, which reached 100% in a multivariate risk model combined with miRNA190. We developed a mathematical formula that calculates the probability of malignancy with a cut-off value of 0.5 above which the patient was at high risk of malignancy. CONCLUSIONS: We have identified for the first time two miRNAs differently expressed in serum of PTC patients who in combination allow the differential diagnosis of thyroid nodules with great accuracy in our study population. Additional studies are required; however, to define whether these results will also be generalized across other patient populations."