Macrofollicular Variant of Follicular Thyroid Carcinoma (MV-FTC) with a Somatic DICER1 Gene Mutation: Case Report and Review of the Literature

Benign thyroid lesions such as multinodular goiter and adenomatoid nodules are well-circumscribed lesions displaying a macrofollicular growth pattern and lack of nuclear atypia. The highly unusual macrofollicular variant of follicular thyroid carcinoma (MV-FTC) mirrors these attributes and is thereby misclassified by cytological examination of fine-needle aspiration biopsies. The MV-FTC diagnosis is instead suggested following histological investigation, in which malignant attributes, most commonly capsular invasion, are noted. The bulk of MV-FTCs described in the literature arise in younger female patients and carry an excellent prognosis. A recent coupling to mutations in the DICER1 tumor suppressor gene has been proposed, possibly indicating aberrancies in micro-RNA (miRNA) patterns as responsible of the tumorigenic process. We describe the cytological, histological and molecular phenotype of a 35 mm large MV-FTC arising in the right thyroid lobe of a 33-year-old female with a family history of multinodular goiter. The tumor was encapsulated and strikingly inconspicuous in terms of cellularity and atypia, but nevertheless displayed multiple foci with capsular invasion. A next-generation molecular screening of tumor DNA revealed missense variants in DICER1 (p. D1709N) and MET (p. T1010I), but no established fusion gene events. After sequencing of germline DNA, the DICER1 mutation was confirmed as somatic, while the MET variant was constitutional. The patient is alive and well, currently awaiting radioiodine treatment. This MV-FTC mirrors previous publications, suggesting that these tumors carry a favorable prognosis and predominantly arise in younger females. Moreover, DICER1 mutations should be considered a common driver event in the development of MV-FTCs.     

Human articular cartilage proteoglycans are not undersulfated in osteoarthritis

Chondroitin sulfate is the major constituent of cartilage. Inadequate sulfate availability results in the production of undersulfated proteoglycans. In osteoarthritis, there is a net loss of articular cartilage proteoglycans. Theoretically, it is possible that during the progress of disease undersulfated glycosaminoglycans are synthesized producing proteoglycans with poorer biological properties. In this study, we tested whether in early human osteoarthritic articular cartilage (Mankin's score of 2 and 3) or more advanced disease (Mankin's score over 3), there are proteoglycans that contain a higher relative amount of nonsulfated chondroitin disaccharide isomer in their chondroitin sulfate chains by analyzing the molar ratios of chondroitin sulfate disaccharide isoforms with fluorophore-assisted carbohydrate electrophoresis. Our results indicated that the nonsulfated disaccharide of chondroitin sulfate formed in average only 1-2% of the total chondroitin sulfate. More important, the molar ratio of nonsulfated disaccharide did not appear to be increased in the osteoarthritic articular cartilage. We conclude that undersulfation of articular cartilage proteoglycans is not present in the human osteoarthritic joint.     

Influence of eotaxin 67G>A polymorphism on plasma eotaxin concentrations in myocardial infarction survivors and healthy controls

Eotaxin (CCL11) is a CC chemokine, whose systemic levels might be associated with coronary artery disease (CAD) and genetic variants predispose to the myocardial infarction (MI). However, the relationship between eotaxin genetic variants and plasma concentrations in CAD patients is still incompletely characterized. We genotyped 311 patients, who survived first MI and 338 controls for a 67G>A single nucleotide polymorphism in the eotaxin gene. By measuring plasma eotaxin concentrations in those subjects we related the former to the presence of 67G>A SNP. There were no differences in eotaxin genotype frequencies between patients and controls. Patient G/G carriers had higher circulating eotaxin levels compared both to G/A and A/A patients (P=0.046) and G/G controls (P=0.028), which might indicate the influence of additional factors (e.g. inflammatory mediators) on eotaxin secretion in those patients. At the same time, eotaxin levels did not differ between patients and controls irrespective of the 67G>A SNP variants they carried. There were no associations between plasma eotaxin levels, biochemical indicators of CAD and the degree of coronary artery stenosis in post-MI patients. Interestingly, some medications taken by the patients (e.g. diuretics and short-acting nitrates) might affect plasma eotaxin levels. In conclusion, our results show that there is no clear association between the presence of eotaxin 67G>A SNP, its plasma levels and CAD parameters in post-MI patients and that circulating eotaxin levels do not differ between subjects with clinical manifestations of coronary atherosclerosis and healthy controls.     

Current challenges in applying gene-driven therapies in clinical lung cancer practice

Over the last twenty years, with the development of gene-driven therapies, numerous new drugs have entered clinical use. Very few of these new drugs are suitable for a large number of patients, and all require molecular genetic testing. In lung cancer, gene-targeted therapy has evolved rapidly and has placed demands on the development of diagnostics and tissue sample preparation and logistics. Rapid diagnosis and prevalence assessment are necessary to determine the prognosis of a lung cancer patient based on the latest research findings. Therefore, the molecular-genetic diagnostic pathway must also be accelerated and matured to do the necessary analyses on small samples. Because lung cancer rebiopsy can be difficult, liquid biopsy techniques should be developed to cover more of the treatable mutations. There are obstacles related to tissue sampling, new genomic techniques and access to gene-driven cancer drugs, including their affordability. With this review and case study, we go into the obstacles faced by our clinic and discuss how to tackle these obstacles in lung cancer. We use lung cancer as an example due to its complexity, though these same obstacles are found in different cancers on a minor scale.