IMPLICAÇÕES CLÍNICAS DO DIAGNÓSTICO MOLECULAR NO MANEJO DO CARCINOMA MEDULAR DE TIREÓIDE HEREDITÁRIO

Hereditary MTC can occur either alone – familial MTC (FMTC) – or as the thyroid manifestation of multiple endocrine neoplasia type 2 (MEN 2) syndromes (MEN 2A and MEN 2B) or others. Three phenotypic subtypes have been reported. MEN 2A(1), MEN 2A(2) and MEN 2A(3). Germline mutations in the RET proto-oncogene cause MEN 2 and recent studies suggest a relationship between specific mutations and different phenotypes in MEN 2 syndromes. The purpose of this study was to identify RET proto-oncogene mutations and analyze a possible relationship between genotype-phenotype in Brazilian kindred with MTC. A total of 57 patients with histopathological and immunohistochemistry diagnosis of MTC were included. This sample was formed from index cases and affected members of 16 familieswith hereditary MTC and 10 individuals with sporadic tumors. DNA was extracted from leukocytes of the affected individuals and relatives. Exons 10, 11, 13, 14, 15 and 16 were amplificated by PCR, using specific primers. The presence of mutation was determined by SSCP, enzymatic restriction analysis and/or automatic sequencing. The phenotypes of hereditary MTC were as follows: 7 MEN 2A, 3 MEN 2A associated with CLA, 3 MEN 2B, 2 FMTC and 1 other forms. We identified mutations at codon 634 in 6 families with MEN 2A, only one kindred had the mutation at codon 618. The 3 kindred with MEN 2A+CLA, both cases of FMTC and the only family classified as other hereditary forms of the MTC presented the mutation in codon 634. A mutation at codon M918T was identified in the 3 individuals with MEN 2B. The genetic screening was able to identified 23 assymtomatic carriers and determine the hereditary MCT pattern in 3 individuals with apparently sporadic tumors. In conclusion, genetic testing can identify affected and assymtomatic individuals with hereditary disease, allowing early diagnosis and treatment. O carcinoma medular de tireóide (CMT) hereditário pode apresentar-se como componente das síndromes de Neoplasia Endócrina Múltipla (NEM 2A e 2B) ou Carcinoma Medular de Tireóide Familiar (CMTF). Diferentes mutações no RET foram identificadas como responsáveis pelo CMT e estudos recentes sugerem uma correlação entre o genótipo-fenótipo, podendo existir uma grande variabilidade de síndromes clínicas associadas às diferentes mutações. O presente estudo realizou a análise molecular do RET em indivíduos com CMT e avaliou a correlação entre fenótipo-genótipo nos afetados e seus familiares. Foram incluídos 57indivíduos com diagnóstico histopatológico/imunohistoquímico de CMT (10 esporádicos e 47 hereditários, provenientes de 16 famílias). O DNA genômico foi extraído de leucócitos periféricos e os exons 10, 11, 13, 14, 15 e/ou 16 do RET amplificados por PCR com primers específicos. A presença de mutações foi determinada por SSCP, restrição enzimática e/ou sequenciamento. Das famílias com CMT hereditário, 7 apresentavam NEM 2A, 3 NEM 2A associada à Líquen Amilóide Cutânea (CLA), 3 NEM 2B, 2 CMTF e 1 outras formas hereditárias. Em 6 famílias com NEM 2A, nas 3 com NEM 2A+CLA e nas 2 com CMTF a mutação estavapresente códon 634. Enquanto que a outra família com NEM 2A apresentava a mutação no códon 618. Nos indivíduos com NEM 2B foi detectada uma mutação de novo no códon M918T. Na família classificada como outros, a mutação também localizava-se no códon 634. O diagnóstico molecular identificou mutações em todos indivíduos com doença hereditária, em 23 indivíduos carreadores sem evidência clínica da neoplasia e em 3 indivíduos com CMT aparentemente esporádico, destacando a importância do rastreamento genético como método diagnóstico

Superior Effects of High-Intensity Interval vs. Moderate-Intensity Continuous Training on Endothelial Function and Cardiorespiratory Fitness in Patients With Type 1 Diabetes: A Randomized Controlled Trial

This study aimed to compare the effect of high-intensity interval training (HIIT) with moderate-intensity continuous training (MCT) on endothelial function, oxidative stress and clinical fitness in patients with type 1 diabetes. Thirty-six type 1 diabetic patients (mean age 23.5 ± 6 years) were randomized into 3 groups: HIIT, MCT, and a non-exercising group (CON). Exercise was performed in a stationary cycle ergometers during 40 min, 3 times/week, for 8 weeks at 50–85% maximal heart rate (HRmax) in HIIT and 50% HRmax in MCT. Endothelial function was measured by flow-mediated dilation (FMD) [endothelium-dependent vasodilation (EDVD)], and smooth-muscle function by nitroglycerin-mediated dilation [endothelium-independent vasodilation (EIVD)]. Peak oxygen consumption (VO2peak) and oxidative stress markers were determined before and after training. Endothelial dysfunction was defined as an increase < 8% in vascular diameter after cuff release. The trial is registered at ClinicalTrials.gov, identifier: NCT03451201. Twenty-seven patients completed the 8-week protocol, 9 in each group (3 random dropouts per group). Mean baseline EDVD was similar in all groups. After training, mean absolute EDVD response improved from baseline in HIIT: + 5.5 ± 5.4%, (P = 0.0059), but remained unchanged in MCT: 0.2 ± 4.1% (P = 0.8593) and in CON: −2.6 ± 6.4% (P = 0.2635). EDVD increase was greater in HIIT vs. MCT (P = 0.0074) and CON (P = 0.0042) (ANOVA with Bonferroni). Baseline VO2peak was similar in all groups (P = 0.96). VO2peak increased 17.6% from baseline after HIIT (P = 0.0001), but only 3% after MCT (P = 0.055); no change was detected in CON (P = 0.63). EIVD was unchanged in all groups (P = 0.18). Glycemic control was similar in all groups. In patients with type 1 diabetes without microvascular complications, 8-week HIIT produced greater improvement in endothelial function and physical fitness than MCT at a similar glycemic control

IMPLICAÇÕES CLÍNICAS DO DIAGNÓSTICO MOLECULAR NO MANEJO DO CARCINOMA MEDULAR DE TIREÓIDE HEREDITÁRIO

Hereditary MTC can occur either alone – familial MTC (FMTC) – or as the thyroid manifestation of multiple endocrine neoplasia type 2 (MEN 2) syndromes (MEN 2A and MEN 2B) or others. Three phenotypic subtypes have been reported. MEN 2A(1), MEN 2A(2) and MEN 2A(3). Germline mutations in the RET proto-oncogene cause MEN 2 and recent studies suggest a relationship between specific mutations and different phenotypes in MEN 2 syndromes. The purpose of this study was to identify RET proto-oncogene mutations and analyze a possible relationship between genotype-phenotype in Brazilian kindred with MTC. A total of 57 patients with histopathological and immunohistochemistry diagnosis of MTC were included. This sample was formed from index cases and affected members of 16 familieswith hereditary MTC and 10 individuals with sporadic tumors. DNA was extracted from leukocytes of the affected individuals and relatives. Exons 10, 11, 13, 14, 15 and 16 were amplificated by PCR, using specific primers. The presence of mutation was determined by SSCP, enzymatic restriction analysis and/or automatic sequencing. The phenotypes of hereditary MTC were as follows: 7 MEN 2A, 3 MEN 2A associated with CLA, 3 MEN 2B, 2 FMTC and 1 other forms. We identified mutations at codon 634 in 6 families with MEN 2A, only one kindred had the mutation at codon 618. The 3 kindred with MEN 2A+CLA, both cases of FMTC and the only family classified as other hereditary forms of the MTC presented the mutation in codon 634. A mutation at codon M918T was identified in the 3 individuals with MEN 2B. The genetic screening was able to identified 23 assymtomatic carriers and determine the hereditary MCT pattern in 3 individuals with apparently sporadic tumors. In conclusion, genetic testing can identify affected and assymtomatic individuals with hereditary disease, allowing early diagnosis and treatment. O carcinoma medular de tireóide (CMT) hereditário pode apresentar-se como componente das síndromes de Neoplasia Endócrina Múltipla (NEM 2A e 2B) ou Carcinoma Medular de Tireóide Familiar (CMTF). Diferentes mutações no RET foram identificadas como responsáveis pelo CMT e estudos recentes sugerem uma correlação entre o genótipo-fenótipo, podendo existir uma grande variabilidade de síndromes clínicas associadas às diferentes mutações. O presente estudo realizou a análise molecular do RET em indivíduos com CMT e avaliou a correlação entre fenótipo-genótipo nos afetados e seus familiares. Foram incluídos 57indivíduos com diagnóstico histopatológico/imunohistoquímico de CMT (10 esporádicos e 47 hereditários, provenientes de 16 famílias). O DNA genômico foi extraído de leucócitos periféricos e os exons 10, 11, 13, 14, 15 e/ou 16 do RET amplificados por PCR com primers específicos. A presença de mutações foi determinada por SSCP, restrição enzimática e/ou sequenciamento. Das famílias com CMT hereditário, 7 apresentavam NEM 2A, 3 NEM 2A associada à Líquen Amilóide Cutânea (CLA), 3 NEM 2B, 2 CMTF e 1 outras formas hereditárias. Em 6 famílias com NEM 2A, nas 3 com NEM 2A+CLA e nas 2 com CMTF a mutação estavapresente códon 634. Enquanto que a outra família com NEM 2A apresentava a mutação no códon 618. Nos indivíduos com NEM 2B foi detectada uma mutação de novo no códon M918T. Na família classificada como outros, a mutação também localizava-se no códon 634. O diagnóstico molecular identificou mutações em todos indivíduos com doença hereditária, em 23 indivíduos carreadores sem evidência clínica da neoplasia e em 3 indivíduos com CMT aparentemente esporádico, destacando a importância do rastreamento genético como método diagnóstico

The RET polymorphic allele S836S is associated with early metastatic disease in patients with hereditary or sporadic medullary thyroid carcinoma.

The possible role of RET variants in modifying the natural course of medullary thyroid carcinoma (MTC) is still a matter of debate. Here, we investigate whether the RET variants L769L, S836S, and G691S/S904S influence disease presentation in hereditary or sporadic MTC patients. One hundred and two patients with hereditary MTC and 81 patients with sporadic MTC attending our institution were evaluated. The frequencies of RET polymorphisms in hereditary MTC were as follows: L769L, 17.3%; S836S, 7.95%; and S904S/G691S, 18.2%. No associations were observed between these polymorphisms and pheochromocytoma, hyperparathyroidism, lymph node, or distant metastasis. However, patients harboring the S836S variant were younger than those without this allele (17±8.2 vs 28.6±14.4 years, P=0.01), suggesting that these patients had metastases at a young age. Accordingly, the cumulative frequency of local and/or distant metastases as estimated by Kaplan-Meier curves showed that lymph node and distant metastases occurred earlier in patients harboring the S836S variant (P=0.003 and P=0.026 respectively). The S836S allele frequency was higher in sporadic MTC patients than in controls (10.5 vs 3.1%, P=0.01). Individuals harboring the S836S variant were younger (38.6±13.3 vs 48.5±16.7 years, P=0.02) and showed a higher percentage of lymph node and distant metastases (P=0.02 and P=0.04 respectively). Kaplan-Meier estimates of lymph node and distant metastases yielded distinct curves for patients with or without the S836S allele (P=0.002 and P=0.001 respectively). Additional analyses using a COX regression model showed that the S836S variant was independently associated with metastatic disease (hazard ratio 2.82 (95% confidence interval 1.51-5.26), P=0.001). In conclusion, the RET S836S variant is associated with early onset and increased risk for metastatic disease in patients with hereditary or sporadic MTC.info:eu-repo/semantics/publishe