Potential new cancer biomarkers revealed by quantum chemistry associated with bioinformatics in the study of selectin polymorphisms

Understanding the complex mechanisms involved in diseases caused by or related to important genetic variants has led to the development of clinically useful biomarkers. However, the increasing number of described variants makes it difficult to identify variants worthy of investigation, and poses challenges to their validation. We combined publicly available datasets and open source robust bioinformatics tools with molecular quantum chemistry methods to investigate the involvement of selectins, important molecules in the cell adhesion process that play a fundamental role in the cancer metastasis process. We applied this strategy to investigate single nucleotide variants (SNPs) in the intronic and UTR regions and missense SNPs with amino acid changes in the SELL, SELP, SELE, and SELPLG genes. We then focused on thyroid cancer, seeking these SNPs potential to identify biomarkers for susceptibility, diagnosis, prognosis, and therapeutic targets. We demonstrated that SELL gene polymorphisms rs2229569, rs1131498, rs4987360, rs4987301 and rs2205849; SELE gene polymorphisms rs1534904 and rs5368; rs3917777, rs2205894 and rs2205893 of SELP gene; and rs7138370, rs7300972 and rs2228315 variants of SELPLG gene may produce important alterations in the DNA structure and consequent changes in the morphology and function of the corresponding proteins. In conclusion, we developed a strategy that may save valuable time and resources in future investigations, as we were able to provide a solid foundation for the selection of selectin gene variants that may become important biomarkers and deserve further investigation in cancer patients. Large-scale clinical studies in different ethnic populations and laboratory experiments are needed to validate our results.

MicroRNA 205-5p and COVID-19 adverse outcomes: Potential molecular biomarker and regulator of the immune response

Coronavirus disease 2019 (COVID-19) is an acute respiratory infection caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The uncontrolled systemic inflammatory response, resulting from the release of large amounts of pro-inflammatory cytokines, is the main mechanism behind severe acute respiratory syndrome and multiple organ failure, the two main causes of death in COVID-19. Epigenetic mechanisms, such as gene expression regulation by microRNAs (miRs), may be at the basis of the immunological changes associated with COVID-19. Therefore, the main objective of the study was to evaluate whether the expression of miRNAs upon hospital admission could predict the risk of fatal COVID-19. To evaluate the level of circulating miRNAs, we used serum samples of COVID-19 patients collected upon hospital admission. Screening of differentially expressed miRNAs in fatal COVID-19 was performed by miRNA-Seq and the validation of miRNAs by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The Mann-Whitney test and receiver operating characteristic (ROC) curve were used to validate the miRNAs, whose potential signaling pathways and biological processes were identified through an in silico approach. A cohort of 100 COVID-19 patients was included in this study. By comparing the circulating levels of miRs between survivors and patients who died due to complications of the infection, we found that the expression of miR-205-5p was increased in those who died during hospitalization, and the expression of both miR-205-5p (area under the curve [AUC] = 0.62, 95% confidence interval [CI] = 0.5-0.7, P = 0.03) and miR-206 (AUC = 0.62, 95% CI = 0.5-0.7, P = 0.03) was increased in those who lately evolved to severe forms of the disease (AUC = 0.70, 95% CI = 0.6-0.8, P = 0.002)."In silico" analysis revealed that miR-205-5p has the potential to enhance the activation of NLPR3 inflammasome and to inhibit vascular endothelial growth factor (VEGF) pathways. Impaired innate immune response against SARS-CoV-2 may be explained by epigenetic mechanisms, which could form early biomarkers of adverse outcomes.

NR3C1 rs6198 Variant May Be Involved in the Relationship of Graves' Disease with Stressful Events

Although stressful events are known to trigger Graves' disease (GD), the mechanisms involved in this process are not well understood. The NR3C1 gene, encoding for the glucocorticoid receptor (GR), presents single nucleotide polymorphisms (SNPs) that are associated with stress-related diseases. To investigate the relationship between NR3C1 SNPs, GD susceptibility, and clinical features, we studied 792 individuals, including 384 patients, among which 209 presented with Graves' orbitopathy (GO), and 408 paired healthy controls. Stressful life events were evaluated in a subset of 59 patients and 66 controls using the IES-R self-report questionnaire. SNPs rs104893913, rs104893909, and rs104893911 appeared at low frequencies and presented similar profiles in patients and controls. However, variant forms of rs6198 were rarer in GD patients, suggesting a protective effect. Stressful events were more common in patients than controls, and were reported to have clearly occurred immediately before the onset of GD symptoms in 23 cases. However, no association was found between these events and rs6198 genotypes or GD/GO characteristics. We suggest that the NR3C1 rs6198 polymorphism may be an important protective factor against GD, but its relationship with stressful events needs further investigation.

ODP272 ROUNDUP IS AN IMPORTANT DISRUPTOR THAT CAUSES PROLIFERATIVE EFFECTS ON NORMAL AND ON CANCER THYROID CELLS

Glyphosate has long be suspected to promote endocrine disruptive and even carcinogenic effects, but little is known about its effect at different concentrations on normal and on cancer thyroid cells. Since the endocrine system responds to low chemical concentrations and abnormal cells may have different sensitivity, it is essential to determine the effects of this compound at different levels, including the Acceptable Occupational Exposure Level (AOEL) and the Acceptable Daily Intake (IDA) doses. We used two human thyroid-derived cell lines strains, Nthy-ori 3-1 (from thyroid normal follicular cells) and TPC-1 (from papillary carcinoma) to test 15 different concentrations of Roundup® Original DI, ranging from 6.5 µg/L to 6.500 µg/L, including AOEL and IDA according to the Technical Note Process No. 25351. 056754/2013-17 of the National Health Surveillance Agency (ANVISA) in Brazil. Trypan blue assay and Cell Counting Kit – 8 (CCK-8) were employed to evaluate cell viability and cytotoxicity. Exposures were made for 24 and 48 hours in technical and biological triplicates. We observed a decrease in the number of viable cells at the 24h exposure compared to 48h in both strains. Exposure of Nthy-ori 3-1 and TPC-1 cells for 24h at the AOEL concentration (160µg/L) caused death of 52% and 58% of the cells, respectively, whereas IDA (830µg/L) resulted in 43% e 58% cell death. These data evidence an important disruptive effect of Roundup Original DI® at the acceptable concentrations. After 48h of exposure, AOEL and IDA concentrations caused a lower number of Nthy-ori 3-1 (19% e 15%) and TPC-1 (29% e 23%) dead cells, respectively, suggesting both thyroid strains have compensatory mechanisms that protect them from longer exposures to the herbicide. The CCK-8 assay, on the contrary, showed a proliferative effect on small concentrations: 6.5 µg/L increased the number of viable Nthy-ori 3-1 and TPC-1 cells to 113% and 118%, respectively, at 24h, and this stimulatory effect persisted after 48h of exposure. In contrast, AOEL and IDA concentrations produced a reduction in the number of both strains cells, likewise observed with the Trypan blue assay. Our data demonstrate that thyroid cells exposed to Roundup Original DI® present a non-monotone dose-response curve, which is a well-known characteristic of an endocrine disruptor. The proliferative effect produced on thyroid cells, especially TPC-1 mutant cells, by very low concentrations of this glyphosate-based herbicide widely used around the world, suggests that it may play a role in the increasing incidence rate of thyroid nodules and/or cancer that have been observed worldwide.

Presentation: No date and time listed

Alternation between toxic and proliferative effects of Roundup® on human thyroid cells at different concentrations

Endocrine-disrupting and carcinogenic effects of glyphosate have long been suspected, but little is known about the effect of compounds used in real life at different concentrations, neither in normal nor in thyroid tumor cells. As cancer cells may have different sensitivities and the effect of the product containing glyphosate may be different from that produced by the active ingredient alone, including the Acceptable Occupational Exposure Level (AOEL=160µg/L) and the Acceptable Daily Intake (ADI=830µg/L) determined by ANVISA, we used two human thyroid-derived cell lines, Nthy-ori 3-1 (from normal follicular cells) and TPC-1 (from papillary carcinoma), to test 15 different concentrations of Roundup® Original DI. Trypan blue (TB), CCK-8 and BrdU assays were used to evaluate cytotoxicity, metabolic activity and proliferation with 24h and 48h exposures in technical and biological triplicates. TB showed an important toxic effect, especially after 24h of exposure, in both cell lines. The AOEL concentration caused the death of 43% and 50% of the Nthy-ori and TPC-1 cells, respectively, in 24 h, while ADI resulted in 35% and 58% of cell death. After 48h of exposure, AOEL and ADI caused a lower number of dead Nthy-ori (33% and 18%) and TPC-1 (33% and 37%) cells, respectively, suggesting that the toxic effect of the product disappears and/or both strains have repair mechanisms that protect them from longer exposures. On the other hand, the CCK-8 assay showed that small concentrations of Roundup have a proliferative effect: 6.5µg/L increased the number of both Nthy-ori and TPC-1 cells at 24h, and the BrdU assay confirmed the stimulatory effect with a 321% increase in the absorbance of Nthy-ori cells at 48h. The herbicide produced even more frequent increases in the BrdU absorbance of TPC-1 cells, mainly at 24h. We conclude that thyroid cells exposed to Roundup present a nonmonotonic dual dose-response curve. Low concentrations of the pesticide, considered acceptable, cause significant cell death but also have an important proliferative effect, especially on TPC-1 cells. This herbicide, widely used around the world, may play a role in the increased incidence rate of thyroid nodules and cancer that has been observed in recent decades.

Clinical utility of the imunohistochemical co-expression of p53 and MDM2 in thyroid follicular lesions

In order to investigate the possible correlation between p53 and MDM2 co-expression with clinicopathological features of differentiated thyroid cancer (DTC) and its use as diagnostic and/or prognostic markers, we used immunohistochemistry to evaluate 317 thyroid samples including 208 DTC and 94 benign nodules, in addition to 15 normal tissues. MDM2 and p53 expression were highly associated (r = 0.7161; p < 0.0001). The co-expression of p53-MDM2 was observed more frequently in malignant lesions (p < 0.0001) and helped characterize follicular patterned lesions distinguishing FVPTC from FA (p < 0.0001) and FVPTC from FTC (p < 0.0001). In addition, p53-MDM2 co-expression was associated with characteristics of less aggressiveness. It was more frequent in patients ≤45 years old (p = 0.0035), with unique tumors (p = 0.0095), tumors <2 cm (p < 0.0001), tumors without extrathyroid invasion (p = 0.0425), without metastasis at evolution (p = 0.0179), and in patients evolving free of disease after treatment (p = 0.0485). We suggest that p53-MDM2 co-expression profile analysis might help establishing diagnostic and determining prognostic of DTC patients.

Polymorphisms of IL-4 and IL-4R are associated to some demographic characteristics of differentiated thyroid cancer patients but are not determinants of risk in the Brazilian population

BACKGROUND

IL-4 is known to present abnormal expression in thyroid tumors and SNPs in the IL-4 and its receptor IL-4R genes are associated to risk and mortality of various types of cancer.

METHODS

In order to evaluate their role in differentiated thyroid cancer (DTC), we investigated genetic frequencies of two IL-4 promoter SNPs (rs2070874 C>T, rs2243250 C>T) and four non-synonymous SNPs of the IL-4R gene (rs1805010 A>G, rs1805012 C>T, rs1805013 C>T, rs1801275 A>G) in 300 DTC patients matched to 300 controls. All patients were managed according to current guidelines and followed-up for a period of 12-252 months (69.20 ± 52.70 months).

RESULTS

Although none of the six investigated SNPs showed association with risk of DTC, rs1805010 was associated with age of diagnosis and the SNPs rs1805012 and rs1801275 were associated to gender. Further, in-silico analysis showed that all these three SNPs were able to cause decreased stability of the protein. We were not able to demonstrate any other association to clinical features of aggressiveness or to patients' prognosis.

CONCLUSIONS

These findings indicate that although genetic variants in IL-4 and IL-4R do not influence the risk or outcome of DTC patients, their influence on the behavior of thyroid tumors deserves further investigation.

Clinical utility of TGFB1 and its receptors (TGFBR1 and TGFBR2) in thyroid nodules: evaluation based on single nucleotide polymorphisms and mRNA analysis

Objective

Abnormalities involving the TGFB1 gene and its receptors are common in several types of cancer and often related to tumor progression. We investigated the role of single nucleotide polymorphisms (SNP) in the susceptibility to cancer, their impact on its features, as well as the role of mRNA expression of these genes in thyroid malignancy.

Methods

We genotyped TGFB1, TGFBR1, and TGFBR2 SNPs in 157 papillary thyroid cancer (PTC) patients and 200 healthy controls. Further, we investigated RNA samples of 47 PTC and 80 benign nodules, searching for differential mRNA expression.

Results

SNPs rs1800472 and rs1800469 were associated with characteristics of PTC aggressiveness. Effect predictor software analysis of nonsynonymous SNP rs1800472 indicated increasing protein stability and post-translational changes. TGFB1 mRNA expression was upregulated in PTC and downregulated in benign samples, differentiating malignant from benign nodules (p<0.0001); PTC from goiter (p<0.0001); and PTC from FA (p<0.0001). TGFBR1 mRNA expression was upregulated in goiter and PTC, but downregulated in FA, distinguishing PTC from goiter (p=0.0049); PTC from FA (p<0.0001); and goiter from FA (p=0.0267). On the other hand, TGFBR2 was downregulated in all histological types analyzed and was not able to differentiate thyroid nodules.

Conclusion

TGFB1 polymorphism rs1800472 may confer greater activity to TGF-β1 in the tumor microenvironment, favoring PTC aggressiveness. Evaluation of TGFB1 and TGFBR1 mRNA levels may be useful to identify malignancy in thyroid nodules.

Epstein-Barr virus induces morphological and molecular changes in thyroid neoplastic cells

Although the evolution of differentiated thyroid cancer (DTC) is usually indolent, some tumors grow fast, metastasize, and may be fatal. Viruses have been associated with many human tumors, especially the Epstein-Barr virus (EBV), which shows a high viral load in DTC. In order to evaluate the ability of the virus to cause morphological and molecular changes in neoplastic thyroid cell lines TPC-1, BCPAP, and 8505C, a viral adaptation was performed for the analysis of EBV cytopathic effect (CPE), viral kinetics and gene expression analysis of oncogenes KRAS, NRAS, HRAS, and TP53. Comparison of inoculated cells with non-inoculated control cells showed that all tumor cell lines were permissive to the virus. The virus caused CPE in the TPC-1 and 8505C, but not in BCPAP cells. Viral kinetic was similar in both BCPAP and 8505C with a point of eclipse at 24 h post infection. TPC-1 cell line displayed a decreasing growth curve, with highest viral load right after inoculation, which decreased over time. There was hyperexpression of TP53 and NRAS in BCPAP cell (p = 0.012 and p = 0.0344, respectively). The 8505C cell line presented NRAS hyperexpression (p = 0.0255), but lower TP53 expression (p = 0.0274). We concluded that neoplastic thyroid cell lines are permissive to EBV that the virus presents different viral kinetic patterns in different cell lines and produces a CPE on both well-differentiated and undifferentiated thyroid cell lines. We also demonstrated that EBV interferes in oncogene expression in thyroid neoplastic cell lines, suggesting that these effects could be related to different tumor progression patterns.

MON-500 Cell Adhesion Molecules mRNA Expression in Thyroid Tumors

Thyroid cancer biology is extremely diverse. While some cases never progress clinically or do so indolently, others evolve aggressively and may even lead to death. Cell adhesion molecules are glycoproteins present in the cell membrane and play an important role in inflammatory and neoplastic diseases by recruiting immune cells to these sites. The aim of the present study was to investigate the role of mRNA expression of SELL, ICAM1 and ITGAL in thyroid tumors and their relationship with lymphocyte infiltration. We evaluated by RT-qPCR technique 191 thyroid nodules including 97 benign (79 females, 17 males; 49.8±12.5 years old) and 94 malignant (71 females, 23 males; 48.3±15.5years old) cases. Clinical and pathology data were obtained from 47 goiters; 50 follicular adenomas (FA); 74 papillary thyroid carcinomas (PTC), including: 29 classic papillary thyroid carcinomas (CPTC), 21 follicular variant of PTC (FVPTC), 12oxifilic variant of PTC (OVPTC), 12 tall cell papillary thyroid carcinomas (TCPTC); and 20 follicular thyroid carcinomas (FTC). All patients were managed according to a standard protocol based on current guidelines and followed-up for 78.7±54.2 months. SELL was more expressed in malignant (0.85±1.54 UA) than in benign (0.54±0.71 UA, p=0.0027) nodules. The same occurred with ICAM1 (0.99±1.41 vs. 0.46±0.85, p=0.0001), but not with ITGAL gene expression (1.04±1.63 vs. 0.76±1.21, p=0.2131). In addition, the expression of SELL was different when we compared PTC with FA (0.94±1.62 UA vs. 0.47±0.72 UA, p=0.0018) and FTC with FA (0.82±2.38 UA vs. 0.47±0.72 UA, p=0.0078). ICAM1 expression was lower in goiters (0.46±0.90 UA) when compared with PTC (0.93±1.22 UA, p=0.0030) and FTC (1.03±3.30 UA, p=0.0207). Higher expression of ICAM1 (1.16±3.04 UA vs. 0.52±0.96 UA, p=0.0064) and ITGAL (1.17±1.54 UA vs. 0.49±1.39 UA, p=0.0244) was observed in tumors with lymphocyte infiltrate. Also, ITGAL gene expression was higher in tumors that had distant metastasis at diagnosis (1.53±2.18 UA vs. 0.57±1.10 UA, p=0.0217). We were not able to demonstrate any association between any of the investigated molecules and patients’ outcome. In conclusion, our data suggest that cell adhesion molecules may play an important role in neoplastic thyroid cells proliferation. In addition, our findings show that gene expression of SELL and ICAM1 may assist in the histological characterization of follicular patterned thyroid nodules.

MON-522 In Silico Analysis of Polymorphism rs2228638 in Neuropillin-1 Demonstrated That This Variant May Hinder EBV Entry into Epithelial Cells

The Epstein-Barr virus (EBV) is the first herpesvirus identified to be associated with human cancers and our group has demonstrated its association to thyroid cancer. It infects the vast majority of the world population causing latent and persistent infection, interfering in the metabolism of the host cells and triggering tumorigenic processes. Neuropillin-1 (NRP-1) is a type I transmembrane glycoprotein distributed on the cell surface of the virus, and considered vital for tumorigenesis. It has been demonstrated that EBV infection was increased by NRP1 expression. However, a conformational alteration of NRP1 could interfere with virus internalization into epithelial cells. The rs2228638 polymorphism of NRP1 may modify the molecule tridimensional configuration. In order to better understand the role of this polymorphism, based on NCBI dbSNP and UniProt databases, we evaluated the effect of the amino acid change in the protein structure using bioinformatics tools including SIFT, Align GVGD, PolyPhen-2, SNAP, PANTHER, PredictSNP, nsSNPAnalyzer, PROVEAN, SNP&GO, PMut and MuPRO. PANTHER prediction indicated that the polymorphic variant could produce a change in function. MuPRO indicated that the amino acid exchange produced by the polymorphism decreases protein stability. However, none of these tools showed conformational alteration. In conclusion, the presence of the rs2228638 polymorphism of NRP-1 may cause functional but not morphological changes that hinder EBV entry into the epithelial cells.

MON-519 In Silico Analysis of rs1042522 and rs1042522 Polymorphic Variants of TP53 Gene

The TP53 gene encodes the p53 protein which is a nuclear phosphoprotein that plays a key role in cell cycle regulation, especially in the transition from G0 to G1. It is located on chromosome 17 at position p13.1 and found at very low levels in normal cells, but it is expressed in large quantities in damaged cells. The most frequent alterations in the TP53 gene are point mutations that cause alteration in the base sequence, resulting in a defective protein. The most frequent alteration occurs in codon 72 (rs1042522). P72R shows an exon 4 polymorphism of the TP53 gene where it there is a substitution of an arginine (Arg) by a proline (Pro). This variant is associated with sporadic thyroid cancer. In addition, codon 72 variants decrease p53’s ability to activate apoptosis and are associated with some autoimmune diseases like Graves’ disease. The codon variant 47 (rs1800371) P47S has a rare polymorphism in the p53 N-terminal transactivation domain that replaces the serine-like wild-type proline (Ser). This variant is associated with impaired pro-apoptotic p53 activity therefore also increasing the risk of cancer. In order to better understand the role of SNPs (rs1042522) and (rs1800371), based on data obtained from the NCBI dbSNP database and UniProt, we evaluated the effect of amino acid alteration on protein structure. We used bioinformatics tools such as SIFT (Sorting Intolerant from Tolerant), Align GVGD, PolyPhen-2, SNAP (Screening for nonacceptable polymorphisms), PANTHER (Protein Analysis Through Evalutionary Relationships), PredictSNP, nsSNPAnalyzer, PROVEAN, SNP & GO, PMut and MuPRO. Rs1042522 and rs1800371 bioinformatic analysis suggested that the amino acid change alters protein structure (Align GVGD tool), decreases the stability (MuPro tool) and function (SNAP) of the protein. SNPs & GO confirmed an association of these polymorphisms with different diseases. We conclude that SNPs rs1042522 and rs1800371 are important in the process of tumorigenesis, corroborating findings from our group and others that suggest that they difficult the action of p53 protein.

MON-504 VEGFA and VEGFR2 Expression in Different Histological Types of Thyroid Nodules: Could Immunohistochemistry Have a Clinical Utility?

Vascular endothelial growth factors (VEGFs) are a family of proteins involved in several elements that play an important role in the development of blood vessels. Besides acting in angiogenesis, VEGFA has important roles in chemotaxis, for macrophages and granulocytes, and vasodilation. VEGFA binds to VEGFR2, that acts on the MAPK and PI3K pathways, fundamental pathways for thyroid carcinogenesis. In order to assess the expression of VEGFA and VEGFR2, in different thyroid nodules, we used a Tissue MicroArray including 91 benign (74 females, 16 males, 49.84±12.65years old) and 125 malignant thyroid nodules (97 females, 28 males, 46.57±14.87 years old). Clinical and pathology data were obtained from 47 goiters; 43 follicular adenomas (FA) and a total of 104 papillary thyroid carcinomas (PTC), including 35 classic papillary thyroid carcinomas (CPTC), 30 follicular variant of PTC (FVPTC), 25 oxifilic variant of PTC (OVPTC), 14 tall cell papillary thyroid carcinomas (TCPTC); and 21 follicular thyroid carcinomas (FTC). All patients were managed according to a standard protocol based on current guidelines and followed-up for 116.9±70.8 months. VEGFA protein expression did not differentiate benign from malignant thyroid nodules. However, VEGFA was more frequently expressed in the less differentiated thyroid tissues. In fact, 95.8% of the FTC had positive expression. On the contrary, the intensity of this protein expression was progressively lower according to the process of cellular dedifferentiation (Goiter: 21.4%; FA: 16.3%; PTC: 8.7% and FTC: 0.0%; x2 = 0.031). There was no difference in VEGFR2 expression between malignant and benign nodules (x2= 0.108), but this protein showed more intense expression in tissues that also presented Hürthle cells (x2 &lt;0.0001). We were not able to find any correlation, neither of VEGFA nor with VEGFR2 expression, and any other feature of aggressiveness, including invasion, metastasis, lymph node metastasis, and distant metastasis. We conclude that VEGFA and VEGFR2 expression may help identify less differentiated tumors and the analysis of a larger cohort may prove the clinical utility of these markers.

Body Mass Index and Prognosis of COVID-19 Infection. A Systematic Review

A better understanding of the SARS-CoV-2 virus behavior and possible risk factors implicated in poor outcome has become an urgent need. We performed a systematic review in order to investigate a possible association between body weight and prognosis among patients diagnosed with COVID-19. We searched in Cochrane Library, EMBASE, MEDLINE, WHO-Global Literature on Coronavirus Disease, OpenGrey, and Medrxiv. We used the ROBINS-I tool or Cross-Sectional/Prevalence Study Quality tool from AHRQ, to evaluate the methodological quality of included studies. Nine studies (two prospective cohorts, four retrospective cohorts and three cross-sectional) were included and assessed the relationship between obesity and COVID-19 prognosis. Risk of bias of the included studies ranged from moderate to critical. Clinical and methodological heterogeneity among them precluded meta-analyses. Most of the included studies showed some degree of association to: (a) higher BMI and worse clinical presentation and (b) obesity and need of hospitalization. The results were inconsistent about the impact of obesity on mortality. Based on limited methodological quality studies, obesity seems to predict poor clinical evolution in patients with COVID-19. Further studies with appropriate prospective design are needed to reduce the uncertainty on this evidence.

ID Proteins May Reduce Aggressiveness of Thyroid Tumors

ID genes have an important function in the cell cycle, and ID proteins may help identify aggressive tumors, besides being considered promising therapeutic targets. However, their role in thyroid tumors is still poorly understood. We examined ID expression and their correlation with diagnostic and prognostic features aiming to find a clinical application in differentiated thyroid carcinoma (DTC) cases. mRNA levels of ID1, ID2, ID3, and ID4 genes were quantified and their expression was observed by immunohistochemistry in 194 thyroid samples including 68 goiters, 16 follicular adenomas, 75 classic papillary thyroid carcinomas, 18 follicular variants of papillary thyroid carcinoma, 5 follicular thyroid carcinomas, and 1 anaplastic thyroid cancer, besides 11 normal thyroid tissues. DTC patients were managed according to standard protocols and followed up for M = 28 ± 16 months. ID2, ID3, and ID4 mRNA levels were higher in benign (2.0 ± 1.9; 0.6 ± 0.6; and 0.7 ± 1.0 AU, respectively) than those in malignant nodules (0.30 ± 0.62; 0.3 ± 0.3; and 0.2 ± 0.3 AU, respectively, p < 0.0001 for all three genes) and were associated with no extra thyroid invasion or metastasis at diagnosis. ID3 nuclear protein expression was higher in benign than that in malignant cells (5.2 ± 0.9 vs 3.0 ± 1.8 AU; p < 0.0001). On the contrary, the cytoplasmic expression of ID3 was higher in malignant than that in benign lesions (5.7 ± 1.5 vs 4.0 ± 1.4 AU; p < 0.0001). Our data indicate that ID genes are involved in thyroid tumorigenesis and suggest these genes act impeding the evolution of more aggressive phenotypes. The different patterns of their tissue expression may help identify malignancy and characterize thyroid lesion aggressiveness.

Serum interleukin measurement may help identify thyroid cancer patients with active disease

BACKGROUND

Investigate the clinical utility of serum interleukin dosages of IL-2, IL-2R, IL-4, IL-6, IL-6R, IL-8, IL-10 and IL-12 in the diagnosis and characterization of patients with DTC. In particular, verify ILs utility in the identification of individuals who are evolving disease-free or with the active disease.

METHODS

We evaluated 200 patients with malignant nodules (100 patients disease-free and 100 patients with recurrence/active disease); 60 benign nodules and 100 healthy controls, serum levels were assessed by ELISA.

RESULTS

All ILs, but not IL-4, differentiated these three groups. We observed that IL-2, 2R and 10 serum concentrations were associated with thyroglobulin levels. Serum IL-2 was able to differentiate patients with active disease from the disease-free with a sensitivity of 98%, specificity of 58%, positive predictive value (PPV) of 70% and negative predictive value (NPV) of 97% (p=0.0007). IL-6R levels differentiated patients with active disease from the disease-free patients with 56% sensitivity, 63% specificity, PPV of 60% and NPV of 59% (p<0.0001). IL-8 values also distinguished patients with active disease from the disease-free ones with sensitivity of 50%, specificity of 76%, PPV of 68% and NPV of 60% (p=0.0025); using IL-12, we obtained a sensitivity value of 73%, specificity of 66%, PPV of 68% and NPV of 71% (p<0.0001). Furthermore, interleukin levels showed association with some tumor characteristics of aggressiveness.

CONCLUSION

We suggest that the serum concentration of ILs may assist in the diagnosis and characterization of tumor malignancy helping identify patients with active disease who deserve closer medical attention.

Gene expression of thyroid-specific transcription factors may help diagnose thyroid lesions but are not determinants of tumor progression

PURPOSE

The role of thyroid-specific transcription factors in thyroid malignancy is still poorly understood, so we investigate thyroid-specific transcription factors gene expression both in benign and in malignant thyroid nodules, aiming to study a possible clinical utility of these molecules.

METHODS

We quantified TTF-1, FOXE1 and PAX8 mRNA levels, relating their expression to diagnostic and prognostic features of thyroid tumors. RNA was extracted from 4 normal thyroid tissues, 101 malignant [99 papillary thyroid carcinomas (PTC) and 2 anaplastic thyroid carcinomas] and 99 benign thyroid lesion tissues [49 goiter and 50 follicular adenomas (FA)].

RESULTS

Levels of mRNA of both FOXE1 (P < 0.0001) and PAX8 (P < 0.0001) genes, but not TTF-1 (P = 0.7056), were higher in benign than in malignant thyroid lesions. FOXE1 was able to identify malignant nodules with 75.8 % sensitivity, 76.1 % specificity, 75.8 % positive predictive value, 76.1 % negative predictive value and 75.9 % accuracy. PAX8 was able to identify malignancy with 60.6 % sensitivity, 81.1 % specificity, 76.9 % positive predictive value, 66.4 % negative predictive value and 70.6 % accuracy. Both FOXE1 and PAX8 gene expression patterns were also able to differentiate FA from the follicular variant of PTC-FVPTC. However, the investigated gene expression was neither associated with any clinical feature of tumor aggressiveness nor associated with recurrence or survival.

CONCLUSIONS

We suggest that FOXE1 and PAX8 gene expression patterns may help to diagnose thyroid nodules, identifying malignancy and characterizing follicular-patterned thyroid lesions, but are not determinants of thyroid tumor progression.