Nir Pillar

The possible involvement of microRNAs in preeclampsia and gestational diabetes mellitus

Great obstetrical syndromes is a collective name for several complications of pregnancy that affect >15% of pregnancies. They may confer adverse pregnancy outcomes and maternal and fetal morbidity, and require close medical monitoring and treatment. The etiology, pathogenesis, and outcome of these syndromes are obscure in the majority of cases. All appear during mid-to-late pregnancy with no reliable biomarkers for early detection and possibly prevention at present. This article focuses on the quest for early reliable markers for preeclampsia and gestational diabetes mellitus (GDM) development, mainly on the involvement of microRNA in the pathogenesis and its possible role as an early biomarker for disease development.

Distinctive pattern of let-7 family microRNAs in aggressive carcinoma of the oral tongue in young patients

Oral cavity squamous cell carcinoma may be more aggressive at presentation and recurrence in young patients compared with older patients. Dysregulation of microRNAs (miRNAs or miRs) has been associated with the development and prognosis of oral cavity cancer. The present study investigated miRNA expression in carcinoma of the oral tongue in young patients. miRNA expression profiles were evaluated in formalin-fixed, paraffin-embedded samples of tumor and normal mucosa from 12 patients aged <30 years old with squamous cell carcinoma of the tongue. The levels of let-7f-5p, miR-30b-5p and let-7e-5p were upregulated in tumors (P<0.05). The expression of let-7f-5p was upregulated in non-aggressive tumors, while the expression of let-7e-5p was upregulated in aggressive tumors, compared with the corresponding normal tissue. Aggressive tumors had higher levels of let-7c, miR-130a-3p, miR-361-5p, miR-99a-5p, miR-29c-3p and let-7d-5p than non-aggressive tumors (P<0.05). The findings remained significant for let-7c upon false-discovery rate correction. An excellent correlation was noticed on validation of NanoString counts by quantitative polymerase chain reaction. The comparison with published findings in adults demonstrated a unique miRNA signature in young patients with aggressive disease. Aggressive oral cavity cancer in patients <30 years old is associated with a distinctive expression pattern of the let-7 family. Larger studies including direct comparison with older patients are warranted.

MicroRNAs as predictors for CNS relapse of systemic diffuse large B-cell lymphoma

Systemic diffuse large B-cell lymphoma (DLBCL) is a potentially curable disease using current regimen of immunochemotherapy. Central nervous system (CNS) relapse is a complication that occurs in approximately 5% of DLBCL patients and is associated with a high fatality rate. Early identification of molecular markers for CNS involvement may serve for the highly needed accurate stratification of patients into risk groups regarding CNS relapse. MicroRNAs (miRNAs) are small non-coding RNA molecules that regulate gene expression at the post-transcriptional level and are known to be involved in DLBCL pathophysiology. In this study, we utilized miRNA multiplex reading of systemic newly diagnosed DLBCL samples obtained from patients with clinical risk factors for CNS involvement whose disease course was distinguished by the presence or absence of subsequent CNS relapse. The analysis detected two differentially expressed miRNAs, miR-20a and miR-30d, that predict for CNS involvement. Replication of these results in different samples was used for validation. We performed bioinformatics miRNA-target enrichment analysis to reveal a number of putative mechanisms for these miRNAs regulation of CNS relapse, including neuronal plasticity and WNT signaling pathway. Altogether, we show that the expression level of two miRNAs may have valuable information that may refine stratification for patients-at-risk for relapse with CNS involvement in DLBCL. Further larger scale studies are needed to shed light on the pathways involved in this disease.

Exosomal microRNAs derived from colorectal cancer-associated fibroblasts: role in driving cancer progression

Colorectal cancer is a global disease with increasing incidence. Mortality is largely attributed to metastatic spread and therefore, a mechanistic dissection of the signals which influence tumor progression is needed. Cancer stroma plays a critical role in tumor proliferation, invasion and chemoresistance. Here, we sought to identify and characterize exosomal microRNAs as mediators of stromal-tumor signaling. In vitro, we demonstrated that fibroblast exosomes are transferred to colorectal cancer cells, with a resultant increase in cellular microRNA levels, impacting proliferation and chemoresistance. To probe this further, exosomal microRNAs were profiled from paired patient-derived normal and cancer-associated fibroblasts, from an ongoing prospective biomarker study. An exosomal cancer-associated fibroblast signature consisting of microRNAs 329, 181a, 199b, 382, 215 and 21 was identified. Of these, miR-21 had highest abundance and was enriched in exosomes. Orthotopic xenografts established with miR-21-overexpressing fibroblasts and CRC cells led to increased liver metastases compared to those established with control fibroblasts. Our data provide a novel stromal exosome signature in colorectal cancer, which has potential for biomarker validation. Furthermore, we confirmed the importance of stromal miR-21 in colorectal cancer progression using an orthotopic model, and propose that exosomes are a vehicle for miR-21 transfer between stromal fibroblasts and cancer cells.

Actionable clinical decisions based on comprehensive genomic evaluation in asymptomatic adults

Whole‐exome sequencing (WES) arises as a new approach in diagnosing individuals affected by multigenic and complex phenotypes. Herein, we aim to examine whether WES is useful in screening asymptomatic individuals for actionable interventions, which has not yet been established. Twenty‐five healthy adults underwent WES, bioinformatics, and manual curation of their exomes. Six participants (24%) harbored significant, management‐changing variants in cancer predisposition genes, American College of Medical Genetics, and genomics reportable cardiac diseases and pharmacogenomic biomarkers that have led to clinical recommendations and interventions. Furthermore, more than 80% of the participants (21) carried 1–3 genetic variants with an associated clinical guideline for an altered drug dosing or administration based on the FDAs table of pharmacogenomics. These results support WES potential not only to answer specific diagnostic questions presented by the relevant personal and/or family history but also to uncover clinically important genetic findings unrelated to the primary indication for sequencing.

Mutations in the NEB gene cause fetal akinesia/arthrogryposis multiplex congenita

We studied a series of patients with fetal akinesia deformation sequence (FADS)/arthrogryposis multiplex congenita (AMC), with nemaline bodies on muscle specimens, which revealed mutations in the NEB gene.

X-linked elliptocytosis with impaired growth is related to mutated AMMECR1.

In this study, we report a family with X-linked recessive syndrome caused by mutated AMMECR1 and characterized by elliptocytosis with or without anemia, midface hypoplasia, proportionate short stature and hearing loss. Recently, mutations in AMMECR1 were reported in two maternal half-brothers, presenting with nephrocalcinosis, midface hypoplasia and, in one of the siblings, deafness and elliptocytosis. AMMECR1 gene is localized in the critical region of contiguous deletion syndrome on Xq22.3 implicated in Alport syndrome, mental retardation, midface hypoplasia, and elliptocytosis (AMME complex). Interestingly, alternative splicing of exon 2, the same exon harboring the truncating mutation, was observed in the proband and in his unaffected mother. Alternative splicing of this exon is predicted to lead to an in-frame deletion. We provide further evidence that mutated AMMECR1 gene is responsible for this clinically recognizable X-linked condition with variable expressivity.

Analysis of microRNAs in familial Mediterranean fever

Objectives Although Familial Mediterranean fever (FMF) is categorized as autosomal recessive, frequent exceptions to this model exist and therefore we aimed to search epigenetic modifications in this disease. Methods Ten M694V homozygous FMF patients (the most severe phenotype) were recruited for this study. Patients with inflammatory flare were excluded. Total RNA was extracted from peripheral blood, and microRNA expression profiled using NanoString nCounter technology. These patients were compared to 10 healthy age- and sex-matched controls. Results Seven hundred nighty-eight mature human miRNAs were probed, 103 of which had expression levels above the negative control probes. Seven miRNAs showed significant differences in expression in samples from FMF patients compared to healthy controls: four miRNAs were upregulated (miR-144-3p, miR-21−5p, miR−4454, and miR-451a), and three were downregulated (miR-107, let−7d−5p, and miR-148b-3p). Conclusion In this pilot study, we identified epigenetic modifications in clinically quiescent FMF patients. More studies are required for exploration of their contribution to FMF pathogenesis and their potential role as clinical biomarkers.

Circulating MicroRNAs: a Potential Biomarker for Cardiac Damage, Inflammatory Response, and Left Ventricular Function Recovery in Pediatric Viral Myocarditis

Viral myocarditis (VM) can be a life-threatening event resulting in cardiac failure, chronic cardiomyopathy, and death. VM typically includes three phases, i.e., acute, subacute, and resolution/chronic. We prospectively investigated cardiac- and inflammatory-associated plasma-circulating miRNA levels in eight pediatric patients with VM during the three stages of the disease. The level of cardiac-associated miR-208a was significantly elevated during the acute phase compared with the subacute and resolution/chronic phases. The level of cardiac- and inflammatory-associated miR-21 was significantly elevated during the acute phase compared to the resolution/chronic phase. Moreover, cardiac-associated miR-208b levels during the subacute phase correlated with systolic left ventricular function recovery as measured during the resolution/chronic phase. The findings of our study demonstrate an association between cardiac damage and the inflammatory response and the expression of miR-208a and miR-21 during the pathological progression of myocarditis. We also found that miR-208b levels exhibit a prognostic significance for left ventricular functional recovery.

SMYD1 is the underlying gene for the AnWj-negative blood group phenotype

AnWj is a high‐incidence blood group antigen associated with three clinical disorders: lymphoid malignancies, immunologic disorders, and autoimmune hemolytic anemia. The aim of this study was to determine the genetic basis of an inherited AnWj‐negative phenotype.