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Glioblastoma is the most common type of malignant brain tumors and the most feared cancer among adults. The poor prognosis among patients affected with this type of cancer is associated with its high-invasiveness and the lack of successful therapies. A comprehensive understanding for the early molecular mechanisms in glioblastoma would definitely enhance the diagnosis and the treatment strategies. Deregulated expression of key genes that are known to be involved in early neurogenesis could be the instigator of brain tumorigenesis. Ras Like Without CAAX 1 (RIT1) gene that encodes an unusual “orphan” GTPase protein belongs to this category of critical genes that are known to be involved in controlling sequential proliferation and differentiation of adult hippocampal neural progenitor cells. In this study, we surveyed RIT1 gene expression by in-silico approaches to determine its spatio-temporal pattern in glioblastoma. Our results revealed a significant and progressive upregulation of RIT1 mRNA levels in various publicly available datasets. RIT1 expression ranked among the top upregulated genes in glioblastoma cohorts and it correlated with poor overall survival. Genetic and epigenetic analysis of RIT1 didn’t reveal any significant aberration that could underlie its deregulated expression. Yet, our results highlighted the possibility of its activity to be transcriptionally controlled by STAT3, one of the main players in the onset of glioblastoma. In conclusion, our study presented for the first time a potential oncogenic role for RIT1 in glioblastoma. Knowing that the RAS superfamily of proteins has created an evolution in the cancer field, RIT1 should be added to this list through further investigations on its possible usage as a biomarker and therapeutic target in glioblastoma.

Discoid lupus erythematosus (DLE) is an autoimmune disorder with a poorly defined etiology. Despite epidemiologic gender and ethnic biases, a clear genetic basis for DLE remains elusive. In this study, we used exome and RNA sequencing technologies to characterize a consanguineous Lebanese family with four affected individuals who presented with classical scalp DLE and generalized folliculitis. Our results unraveled a novel biallelic variant c.1313C > A leading to a missense substitution p.(Thr438Asn) in TRAF3IP2(NM_147200.3). Expression studies in cultured cells revealed mis-localization of the mutated protein. Functional characterization of the mutated protein showed significant reduction in the physical interaction with the interleukin 17-A receptor (IL17RA), while interaction with TRAF6 was unaffected. By conducting a differential genome-wide transcriptomics analysis between affected and non-affected individuals, we showed that the hair follicle differentiation pathway is drastically suppressed, whereas cytokine and inflammation responses are significantly upregulated. Furthermore, our results were highly concordant with molecular signatures in patients with DLE from a public dataset. In conclusion, this is the first report on a new putative role for TRAF3IP2 in the etiology of DLE. The identified molecular features associated with this gene could pave the way for better DLE-targeted treatment.

Transcription factors (TFs) play important roles in many biochemical processes. Many human genetic disorders have been associated with mutations in the genes encoding these transcription factors, and so those mutations became targets for medications and drug design. In parallel, since many transcription factors act either as tumor suppressors or oncogenes, their mutations are mostly associated with cancer. In this perspective, we studied the GATA3 transcription factor when bound to DNA in a crystal structure and assessed the effect of different mutations encountered in patients with different diseases and phenotypes. We generated all missense mutants of GATA3 protein and DNA within the adjacent and the opposite GATA3:DNA complex models. We mutated every amino acid and studied the new binding of the complex after each mutation. Similarly, we did for every DNA base. We applied Poisson-Boltzmann electrostatic calculations feeding into free energy calculations. After analyzing our data, we identified amino acids and DNA bases keys for binding. Furthermore, we validated those findings against experimental genetic data. Our results are the first to propose in silico modeling for GATA:DNA bound complexes that could be used to score effects of missense mutations in other classes of transcription factors involved in common and genetic diseases.

The transmission of the contagious COVID-19 is known to be highly dependent on individual viral dynamics. Since the cycle threshold (Ct) is the only semi-quantitative viral measurement that could reflect infectivity, we utilized Ct values to forecast COVID-19 incidences. Our COVID-19 cohort (n=9531), retrieved from a single representative cross-sectional virology test center in Lebanon, revealed that low daily mean Ct values are followed by an increase in the number of national positive COVID-19 cases. A subset of the data was used to develop a deep neural network model, tune its hyperparameters, and optimize the weights for minimal mean square error of prediction. The final model’s accuracy is reported by comparing its predictions with an unseen dataset. Our model was the first to capture the interaction of the previously reported Ct values with the upcoming number of COVID-19 cases and any temporal effects that arise from population dynamics. Our model was deployed as a publicly available and easy-to-use estimator to facilitate prospective validation. Our model has potential application in predicting COVID-19 incidences in other countries and in assessing post-vaccination policies. Aside from emphasizing patient responsibility in adopting early testing practices, this study proposed and validated viral load measurement as a rigid input that can enhance outcomes and precision of viral disease predicting models.

Thalidomide is still by excellence the mysterious drug that fascinated, blurred, misled, and changed the scientific community perspectives and policies. It was introduced in the 1950’s as a sedative drug, then shortly withdrawn because of the devastating birth defects that affected tens of thousands throughout more than 40 countries. Back into the market in the mid 1990’s and 2000’s the drug is now being used to treat skin immune-related conditions and some cancers like multiple myeloma. Despite numerous beneficial effects which led to the development of new analogs, its direct mechanisms of action are still elusive. The identification of CRBN and TBX5 as potential direct ligands for this drug have opened the way to better understand its efficiency and its failure.We hereby review these mechanisms and provide evidence that could explain why thalidomide failed to make it as a drug of choice in lung cancer treatment. Linking the genetic signature of TBX2 subfamily in these tumors to their inability to respond properly to thalidomide raises concerns of worsening lung cancer patients’ health if this drug is utilized.

Mandibular micrognathism (MM) is an underdeveloped mandible resulting from complex interactions between genetic and environmental factors. Prior research focused mainly on the genetic determinants of mandibular retrognathism, not necessarily reflecting micrognathism, thus supporting the need to study MM. This study aimed to explore the inheritance pattern and identify the candidate genes involved in the development and familial transmission of MM.Diagnosing probands with MM was based on clinical and lateral cephalometric data. The pedigrees were drawn for 11 identified families, 5 of whom accepted to undergo detailed data and biospecimen collection. These families included 15 MM and 13 non-MM subjects over 2-3 generations. The procedure involved the withdrawal of 5 mL of blood. Genomic DNA was isolated from blood cells to investigate protein-coding regions via whole exome sequencing. Standardized filtering steps were employed, and candidate genes were identified.Most of the pedigrees suggested a Mendelian inheritance pattern and segregated in an autosomal-dominant manner. One of the families, which also underwent biospecimen, displayed an X-linked inheritance pattern of the trait. Genetic screening disclosed 8 potentially novel genes (GLUD2, ADGRG4, ARSH, TGIF1, FGFR3, ZNF181, INTS7, and WNT6). None of the recognized exonic regions were previously reported.Eight novel genes were identified in association with MM in the largest number of families reported to date. The genes were X-linked in 1 family, a finding previously not observed in mandibular genetics.

Genetically inherited defects in lipoprotein metabolism affect more than 10 million individuals around the globe with preponderance in some parts where consanguinity played a major role in establishing founder mutations. Mutations in four genes have been so far linked to the dominant and recessive form of the disease. Those players encode major proteins implicated in cholesterol regulation, namely, the low-density lipoprotein receptor (LDLR) and its associate protein 1 (LDLRAP1), the proprotein convertase substilin/kexin type 9 (PCSK9), and the apolipoprotein B (APOB). Single mutations or compound mutations in one of these genes are enough to account for a spectrum of mild to severe phenotypes. However, recently several reports have identified digenic mutations in familial cases that do not necessarily reflect a much severe phenotype. Yet, data in the literature supporting this notion are still lacking. Herein, we review all the reported cases of digenic mutations focusing on the biological impact of gene dosage and the potential protective effects of single-nucleotide polymorphisms linked to hypolipidemia. We also highlight the difficulty of establishing phenotype–genotype correlations in digenic familial hypercholesterolemia cases due to the complexity and heterogeneity of the phenotypes and the still faulty in silico pathogenicity scoring system. We finally emphasize the importance of having a whole exome/genome sequencing approach for all familial cases of familial hyperlipidemia to better understand the genetic and clinical course of the disease.

A sudden outbreak of pneumonia caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has rapidly spread all over the world facilitating the declaration of the resultant disease as a pandemic in March,2020. In Lebanon, the fast action of announcing a state of emergency with strict measures was among the factors that helped in achieving a successful containment of the disease in the country. Predisposing factors for acquiring COVID-19 and for developing a severe form of this disease were postulated to be related to epidemiological and clinical characteristics as well as the genomics signature of a given population or its environment. Biological markers such as the ABO blood group system was amongst those factors that were proposed to be linked to the variability in the disease course and/or the prevalence of this infection among different groups. We therefore conducted the first retrospective case-control study in the Middle-East and North Africa that tackles the association between the blood group types and the susceptibility as well as the severity of SARS-CoV2 infection. Opposing to the current acknowledged hypothesis, our results have challenged the association significance of this system with COVID-19. Herein, we highlighted the importance of studying larger cohorts using more rigorous approaches to diminish the potential confounding effect of some underlying comorbidities and genetic variants that are known to be associated with the ABO blood group system.

Supplemental Digital Content is available in the text., Background: Cardiac troponin I (TNNI3) gene mutations account for 3% of hypertrophic cardiomyopathy and carriers have a heterogeneous phenotype, with increased risk of sudden cardiac death (SCD). Only one mutation (p.Arg21Cys) has been reported in the N terminus of the protein. In model organisms, it impairs PKA (protein kinase A) phosphorylation, increases calcium sensitivity, and causes diastolic dysfunction. The phenotype of this unique mutation in patients with hypertrophic cardiomyopathy remains unknown. Methods: We sequenced 29 families with hypertrophic cardiomyopathy enriched for pediatric-onset disease and identified 5 families with the TNNI3 p.Arg21Cys mutation. Using cascade screening, we studied the clinical phenotype of 57 individuals from the 5 families with TNNI3 p.Arg21Cys-related cardiomyopathy. We performed survival analysis investigating the age at first SCD in carriers of the mutation. Results: All 5 families with TNNI3 p.Arg21Cys were from South Lebanon. TNNI3 p.Arg21Cys-related cardiomyopathy manifested a malignant phenotype—SCD occurred in 30 (53%) of 57 affected individuals at a median age of 22.5 years. In select carriers without left ventricular hypertrophy on echocardiogram, SCD occurred, myocyte disarray was found on autopsy heart, and tissue Doppler and cardiac magnetic resonance imaging identified subclinical disease features such as diastolic dysfunction and late gadolinium enhancement. Conclusions: The TNNI3 p.Arg21Cys mutation has a founder effect in South Lebanon and causes malignant hypertrophic cardiomyopathy with early SCD even in the absence of hypertrophy. Genetic diagnosis with this mutation may be sufficient for risk stratification for SCD.

A sudden outbreak of pneumonia caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has rapidly spread all over the world facilitating the declaration of the resultant disease as a pandemic in March,2020. In Lebanon, the fast action of announcing a state of emergency with strict measures was among the factors that helped in achieving a successful containment of the disease in the country. Predisposing factors for acquiring COVID-19 and for developing a severe form of this disease were postulated to be related to epidemiological and clinical characteristics as well as the genomics signature of a given population or its environment. Biological markers such as the ABO blood group system was amongst those factors that were proposed to be linked to the variability in the disease course and/or the prevalence of this infection among different groups. We therefore conducted the first retrospective case-control study in the Middle-East and North Africa that tackles the association between the blood group types and the susceptibility as well as the severity of SARS-CoV2 infection. Opposing to the current acknowledged hypothesis, our results have challenged the association significance of this system with COVID-19. Herein, we highlighted the importance of studying larger cohorts using more rigorous approaches to diminish the potential confounding effect of some underlying comorbidities and genetic variants that are known to be associated with the ABO blood group system.

Glioblastoma is the most common type of malignant brain tumors and the most feared cancer among adults. Its high invasiveness and the lack of successful therapies are responsible for the poor prognosis among these patients. A comprehensive understanding for the early molecular mechanisms in glioblastoma would definitely enhance its diagnosis and treatment strategies. Based on in vitro and in vivo models, it was recently postulated that the deregulated expression of key genes that are known to be involved in early neurogenesis could be the instigator of brain tumorigenesis. RIT1 (Ras Like Without CAAX 1) which encodes an unusual “orphan” GTPase protein belongs to this category of critical genes involved in controlling sequential proliferation and differentiation of adult hippocampal neural progenitor cells. As such, we surveyed RIT1 expression and its potential role in glioblastoma by in-silico means. Our results revealed a significant and progressive upregulation of RIT1 expression in various publicly available datasets. RIT1 expression ranked among the top upregulated genes in glioblastoma cohorts and correlated with poor overall survival. Genetic and epigenetic analysis of RIT1 didn’t reveal significant aberrations that could underlie its deregulated expression. Moreover, our results pointed on RIT1 transcriptional activity that could be significantly controlled by STAT3, one of the main players in the onset of glioblastoma. In conclusion, our results are the first proof for the role of RIT1 as an oncogene in glioblastoma paving the way for its potential use as a biomarker and therapeutic target as is the case of the other members in the RAS family.

Introduction In the absence of a universally accepted association between smoking and COVID-19 health outcomes, we investigated this relationship in a representative cohort from one of the world’s highest tobacco consuming regions. This is the first report from the Middle East and North Africa that tackles specifically the association of smoking and COVID-19 mortality while demonstrating a novel sex-discrepancy in the survival rates among patients. Methods Clinical data for 743 hospitalized COVID-19 patients was retrospectively collected from the leading centre for COVID-19 testing and treatment in Lebanon. Logistic regression, Kaplan-Meier survival curves and Cox proportional hazards model adjusted for age and stratified by sex were used to assess the association between the current cigarette smoking status of patients and COVID-19 outcomes. Results In addition to the high smoking prevalence among our hospitalized COVID-19 patients (42.3%), enrolled smokers tended to have higher reported ICU admissions (28.3% vs 16.6%, p Conclusion A high smoking prevalence was detected in our hospitalized COVID-19 cohort combined with worse prognosis and higher mortality rate in smoking patients. Our study was the first to highlight potential sex-specific consequences for smoking on COVID-19 outcomes that might further explain the higher vulnerability to death from this disease among men.

// Athar A. Khalil 1 , Smruthy Sivakumar 2, 3 , Frances Anthony San Lucas 2 , Tina McDowell 4 , Wenhua Lang 4 , Kazuhiro Tabata 5 , Junya Fujimoto 4 , Yasushi Yatabe 6 , Avrum Spira 7 , Paul Scheet 2, 3 , Georges Nemer 1, * and Humam Kadara 1, 2, * 1 Department of Biochemistry and Molecular Genetics, Faculty of Medicine, American University of Beirut, Beirut, Lebanon 2 Department of Epidemiology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA 3 University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, Texas, USA 4 Department of Translational Molecular Pathology, University of Texas MD Anderson Cancer Center, Houston, Texas, USA 5 Graduate School of Biomedical Science, Nagasaki University, Nagasaki, Japan 6 Department of Pathology, Aichi Cancer Center, Nagoya, Japan 7 Section of Computational Biomedicine, School of Medicine, Boston University, Boston, Massachusetts, USA * Contributed equally as co-senior authors Correspondence to: Georges Nemer, email: gn08@aub.edu.lb Humam Kadara, email: hk94@aub.edu.lb Keywords: NSCLC, smoking, preneoplasia, airway field of injury, early detection Received: May 23, 2017 Accepted: July 26, 2017 Published: August 04, 2017 ABSTRACT The TBX2 subfamily ( TBXs 2, 3, 4 and 5) transactivates or represses genes involved in lung organogenesis. Yet TBX2 subfamily expression in pathogenesis of non-small cell lung cancer (NSCLC), the most common lung malignancy, remains elusive. We sought to probe the expression profile of the TBX2 subfamily in early phases of NSCLC. Expression of TBX2 subfamily was analyzed in datasets of pan-normal specimens as well as NSCLCs and normal lung tissues. TBX2 subfamily expression in matched normal lungs, premalignant hyperplasias and NSCLCs was profiled by transcriptome sequencing. TBX2 subfamily expression was evaluated in the cancerization field consisting of matched NSCLCs and adjacent cytologically-normal airways relative to distant normal lungs and in a dataset of normal bronchial samples from smokers with indeterminate nodules suspicious for malignancy. Statistical analysis was performed using R. TBX2 subfamily expression was markedly elevated in normal lungs relative to other organ-specific normal tissues. Expression of the TBXs was significantly suppressed in NSCLCs relative to normal lungs ( P < 10 −9 ). TBX2 subfamily was significantly progressively decreased across premalignant lesions and NSCLCs relative to normal lungs ( P < 10 −4 ). The subfamily was significantly suppressed in NSCLCs and adjacent normal-appearing airways relative to distant normal lung tissues ( P < 10 −15 ). Further, suppressed TBX2 subfamily expression in normal bronchi was associated with lung cancer status ( P < 10 −5 ) in smokers. Our findings suggest that the TBX2 subfamily is notably suppressed in human NSCLC pathogenesis and may serve as a high-potential biomarker for early lung cancer detection in high-risk smokers.

Background Hearing loss (HL) represents the most common congenital sensory impairment with an incidence of 1-5 per 1000 live births. Non-syndromic hearing loss (NSHL) is an isolated finding that is not part of any other disorder accounting for 70% of all genetic hearing loss cases. Methods In the current study, we report a multifactorial genetic mode of inheritance in a NSHL consanguineous family using exome sequencing technology. We evaluated the possible effects of the single nucleotide variants (SNVs) detected in our patients using in silico methods. Results Two bi-allelic SNVs were detected in the affected patients; a MYO15A (. p.V485A) variant, and a novel MITF (p.P338L) variant. Along with these homozygous mutations, we detected two heterozygous variants in well described hearing loss genes (MYO7A and MYH14). The novel p. Pro338Leu missense mutation on the MITF protein was predicted to change the protein structure and function. Conclusion The novel MITF variant is the first bi-allelic SNV in this gene to be associated with an autosomal recessive non-syndromic HL case with a post-lingual onset. Our findings highlight the importance of whole exome sequencing for a comprehensive assessment of the genetic heterogeneity of HL.

Hypertrophic Cardiomyopathy (HCM) occurs in 1 of every 500 people and has a wide phenotypic variability. In the majority of cases, HCM is caused by known mutations in genes that code for sarcomere proteins. Although gene testing is widely available for HCM, knowing the phenotype caused by different gene mutations remains a challenging task. We recruited 28 families with HCM, of which 19 (67.8%) have at least one patient with pediatric onset. Index patients from 20 families received targeted sequencing for a panel of genes including TNNI3 , and 7 families received Sanger sequencing for the TNNI3 . We identified a missense mutation p.R21C in TNNI3 segregating with HCM in four families from South Lebanon. Through cascade screening, we identified 30 patients from the four families; twenty of them (67%) had a clinical diagnosis of HCM with a median age of 37 years, while 9 (30%), with a median age 21 years, had no evidence of HCM on echocardiography. An additional 27 members of the families had evidence of HCM, including 22 with SCD in the setting of no past medical history, and their carrier status for p.R21C was implied from the pedigrees. Survival analysis for 57 HCM patients with the mutation revealed a markedly decreased age at first adverse event as compared to 47 HCM patients with the MYBPC3 p.R502W mutation. Founder mutations in HCM that cause a severe phenotype are uncommon. The p.R21C mutation in TNNI3 is the first HCM mutation described in the Lebanese population and has a founder effect in South Lebanon. Early and more frequent screening with different imaging modalities as well as tailored management might be warranted for carriers of this mutation.

(1) The TBX2 subfamily of transcription factors (TBXs 2, 3, 4 and 5) are markedly down-regulated in human non-small cell lung cancer (NSCLC) and exert tumor suppressor effects in lung malignancy. Yet, mechanisms underlying suppressed expression of the TBX2 subfamily in NSCLC are elusive. Here, we interrogated probable epigenetic mechanisms in suppressed expression of the TBX2 subfamily in human NSCLC. (2) TBX2 subfamily gene expression and methylation levels in NSCLC and normal lung tissues were surveyed using publicly available RNA-sequence and genome-wide methylation datasets. Methylation &beta, values of the four genes were statistically compared between NSCLCs and normal lung tissues, correlated with gene expression levels, and interrogated with clinicopathological variables. Expression and methylation levels of TBXs were quantified in NSCLC cells using real-time PCR and methylation-specific PCR assays, respectively. Effects of the DNA methyltransferase inhibitor 5-azacytidine (Aza) on TBX2 subfamily expression were assessed in NSCLC cells. Impact of TBX2 subfamily expression on Aza-treated cells was evaluated by RNA interference. (3) All four TBXs were significantly hypermethylated in NSCLCs relative to normal lung tissues (p &lt, 0.05). Methylation &beta, values of the genes, with exception of TBX2, were significantly inversely correlated with corresponding mRNA expression levels (p &lt, 0.05). We found no statistically significant differences in hypermethylation levels of the TBX2 subfamily by clinicopathological features including stage and tobacco history. Expression levels of the TBX genes were overall suppressed in NSCLC cells relative to normal alveolar cells. Members of the subfamily were significantly hypermethylated in all tested NSCLC cell lines relative to normal alveolar cells. Treatment with Aza induced the expression of the TBX2 subfamily concomitant with NSCLC cell growth inhibition. Further, simultaneous knockdown of the four TBX genes markedly reduced anti-growth effects of Aza in NSCLC cells. (4) Our study sheds light on new epigenetic profiles in the molecular pathogenesis of human NSCLC.

Background Cardiomyopathies affect more than 0.5% of the general population. They are associated with high risk of sudden cardiac death, which can result from either heart failure or electrical abnormalities. Although different mechanisms underlie the various types of cardiomyopathies, a principal pathology is common to all and is usually at the level of the cardiac muscle. With a relatively high incidence rate in most countries, and a subsequent major health burden on both the families and governments, cardiomyopathies are gaining more attention by researchers and pharmaceutical companies as well as health government bodies. In Lebanon, there is no official data about the spectrum of the diseases in terms of their respective prevalence, clinical, or genetic profiles. Methods We used exome sequencing to unravel the genetic basis of idiopathic cases of cardiomyopathies in Lebanon, a relatively small country with high rates of consanguineous marriages. Results Five cases were diagnosed with different forms of cardiomyopathies, and exome sequencing revealed the presence of already documented or novel mutations in known genes in three cases: LMNA for an Emery Dreifuss Muscular Dystrophy case, PKP2 for an arrhythmogenic right ventricle dysplasia case, and MYPN for a dilated cardiomyopathy case. Interestingly two brothers with hypertrophic cardiomyopathy have a novel missense variation in NPR1, the gene encoding the natriuretic peptides receptor type I, not reported previously to be causing cardiomyopathies. Conclusion Our results unravel novel mutations in known genes implicated in cardiomyopathies in Lebanon. Changes in clinical management however, require genetic profiling of a larger cohort of patients. Electronic supplementary material The online version of this article (10.1186/s12920-019-0478-7) contains supplementary material, which is available to authorized users.

Table S1. Whole-exome sequencing filtered results of patient MR37 with non-sense variants or Indels minor allele frequencies’

The Polymerase Chain Reaction (PCR) is the most valuable tool that marked the history of molecular biology since the discovery of the DNA structure by Watson and Crick. Its impact on human health over the last 30 years had lead researchers in the field to put strict rules referred to as the Minimum Information for publication of Quantitative real-time PCR Experiments (MIQE) guidelines since 2009. The aim of the current analysis is to shed light on the practice of applying and citing the original MIQE in the published articles over the last decade. We showed that qPCR is a global technique, but the usage of the MIQE is still lagging in the emerging economies around the globe. We have shown that researchers following the MIQE have better chances of publishing highly cited papers. The MIQE represent the laws for this technique: they enslave us, molecular biologists, into a strict path with financial burdens, but they free us from the “human-errors” a machine would impose on us. As science seeks perfection especially when dealing with human problems, the MIQE, as assessed by the publications' quality over the years, did indeed achieve this step forward towards making the PCR an infallible tool.

T-box (TBX) transcription factors are evolutionary conserved genes and master transcriptional regulators. In mammals, TBX2 subfamily (TBX2, TBX3, TBX4, and TBX5) genes are expressed in the developing lung bud and tracheae. Our group previously showed that the expression of TBX2 subfamily was significantly high in human normal lungs, but markedly suppressed in lung adenocarcinoma (LUAD). To further elucidate their role in LUAD pathogenesis, we first confirmed abundant expression of protein products of the four members by immunostaining in adult human normal lung tissues. We also found overall suppressed expression of these genes and their corresponding proteins in a panel of human LUAD cell lines. Transient over-expression of each of the genes in human (NCI-H1299), and mouse (MDA-F471) derived lung cancer cells was found to significantly inhibit growth and proliferation as well as induce apoptosis. Genome-wide transcriptomic analyses on NCI-H1299 cells, overexpressing TBX2 gene subfamily, unraveled novel regulatory pathways. These included, among others, inhibition of cell cycle progression but more importantly activation of the histone demethylase pathway. When using a pattern-matching algorithm, we showed that TBX's overexpression mimic molecular signatures from azacitidine treated NCI-H1299 cells which in turn are inversely correlated to expression profiles of both human and murine lung tumors relative to matched normal lung. In conclusion, we showed that the TBX2 subfamily genes play a critical tumor suppressor role in lung cancer pathogenesis through regulating its methylating pattern, making them putative candidates for epigenetic therapy in LUAD.

Background Cutaneous malformations are at times associated with some forms of congenital heart defects. Many a times subtle cutaneous phenotypes maybe overlooked as their significance on the lives of individuals is minimal. Lebanon represents an area of high consanguinity, where the rates can go beyond 70% in some districts. For the past 6 years, we have been studying several genodermatoses in Lebanon including those with cardiac malformations. Objectives The main aim of this study is to document the genetic basis of a familial case of Axenfeld-Rieger Syndrome (ARS) with a mild cutaneous phenotype represented histologically with degeneration/ absence of hair follicles and incomplete formation of sebaceous and eccrine glands, in addition to the cardiac and ocular phenotypes. Methods Whole exome sequencing was performed on two identical-twins with ARS along with their affected father and non-affected mother. Sanger sequencing was used to confirm the mutation, and the effects of the mutations on protein function was assessed in vitro using transient transfections. Results A novel mutation inFOXC1 designated p.L240Rfs*75 was found in both twins and their father. The affected individuals share also a rare documented variant in NFATC1 designated p.V197 M. Both were absent from 200 Lebanese exomes. Our in vitro results suggested a gain of function activity of the FOXC1/NFATC1 complex, confirming its documented role in controlling murine hair follicle stem cells quiescence and regeneration. Conclusion This is the first documented human case with a mutation inFOXC1 regulating multi-organ developmental pathways that reflect a conserved mechanism in cell differentiation and proliferation.

Computational docking and scoring techniques have revolutionized structural bioinformatics by providing unprecedented insights on key aspects of ligand-receptor interaction. Docking is used for optimizing known drugs and for identifying novel binders by predicting their binding mode and affinity. AutoDock and AutoDockTools are free of charge techniques that have been extensively cited in the literature as essential tools in structure-based drug design. Moreover, these methods are fast enough to permit virtual screening of ligand libraries containing tens of thousands of compounds. However using Autodock requires some knowledge in programming which creates a limitation for biologists and makes them prone for commercial applications. Here, we selected a relevant target involved in the progression of Alzheimer disease and provided a fully reproducible docking protocol. This example will show how docking techniques would be an important asset to identify new BACE1 inhibitors. The following friendly user tutorial targets both undergraduate and graduate students, allowing them to understand docking as a computational tool for structure-based drug design.

Congenital heart disease is the leading cause of death in the first year of life. Mutations only in few genes have been linked to some cases of CHD. Thalidomide was used by pregnant women for morning sickness but was removed from the market because it caused severe malformations including CHDs. We used both in silico docking software, and in vitro molecular and biochemical methods to document a novel interaction involving Thalidomide, TBX5, and HAND2. Thalidomide binds readily to TBX5 through amino acids R81, R82, and K226 all implicated in DNA binding. It reduces TBX5 binding to DNA by 40%, and suppresses TBX5 mediated activation of the NPPA and VEGF promoters by 70%. We documented a novel interaction between TBX5 and HAND2, and showed that a p.G202V HAND2 variant associated with CHD and coronary artery diseases found in a large Lebanese family with high consanguinity, drastically inhibited this interaction by 90%. Similarly, thalidomide inhibited the TBX5/HAND2 physical interaction, and the in silico docking revealed that the same amino acids involved in the interaction of TBX5 with DNA are also involved in its binding to HAND2. Our results establish a HAND2/TBX5 pathway implicated in heart development and diseases.

Computational docking and scoring techniques have revolutionized structural bioinformatics by providing unprecedented insights on key aspects of ligand-receptor interaction. Docking is used for optimizing known drugs and for identifying novel binders by predicting their binding mode and affinity. AutoDock and AutoDockTools are free of charge techniques that have been extensively cited in the literature as essential tools in structure-based drug design. Moreover, these methods are fast enough to permit virtual screening of ligand libraries containing tens of thousands of compounds. However using Autodock requires some knowledge in programming which creates a limitation for biologists and makes them prone for commercial applications. Here, we selected a relevant target involved in the progression of Alzheimer disease and provided a fully reproducible docking protocol. This example will show how docking techniques would be an important asset to identify new BACE1 inhibitors. The following friendly user tutorial targets both undergraduate and graduate students, allowing them to understand docking as a computational tool for structure-based drug design.

T-box (TBX) transcription factors are evolutionary conserved genes and master regulators of transcription repression and activation. In mammals, 18 members were described functionally and structurally, of which the TBX2 subfamily (TBX2, TBX3, TBX4, TBX5) genes were shown to be expressed early on in the developing lung bud and tracheae. Despite these insights into the role of the TBX2 subfamily in normal lung organogenesis, little is known about the role of these genes in pathological pulmonary conditions in humans; particularly lung cancer, an aggressive malignancy that is the leading cause of cancer-deaths worldwide. To fill this void, our group previously surveyed the expression of TBX2 subfamily in various publicly available datasets and found that all four members were preferentially and highly expressed in human normal lung, but markedly and consistently suppressed in lung adenocarcinoma (LUAD) the most common histological subtype of lung cancer. We also showed that the subfamily was also suppressed in preneoplastic lesions preceding the development of LUADs. Following the above and to further elucidate the role of the TBX2 subfamily in LUAD pathogenesis, we first probed and confirmed abundant expression of protein products of the four members by immunostaining in adult human normal lung tissues. On the other hand, quantitative real-time PCR and western blotting analyses demonstrated overall suppressed expression of the genes and corresponding proteins in a panel of human LUAD cell lines. Transient over-expression of each of the four genes in human LUAD cell lines (H1299 and H1944) was found to overall significantly inhibit cancer cell growth and proliferation. Additionally, over-expression of the four genes induced apoptosis, evidenced by sub-G0/G1 accumulation following cell cycle analysis, in both cell lines (ranging from 40% to 90% compared to control). To understand genome-wide effects of TBX2 subfamily in LUAD, we interrogated global expression programs downstream of these transcription factors by RNA-Seq in H1299 cells engineered to over-express the four members separately. We unraveled novel signaling cues signifying canonical pathways found in our analysis to be directly regulated by members of the TBX2 subfamily. These included, among others, inhibition of cell cycle progression and glycolysis, suppression of pathways mediated by epidermal growth factor (EGFR) and WNT signaling and activation of the major anti-tumor immune marker interferon gamma (IFNG). All in all, our findings point to tumor suppressor roles for TBX2 subfamily in human LUAD pathogenesis and suggest “oncophenotypes” downstream of these factors as putative targets for lung cancer therapy. Citation Format: Athar Khalil, Nehme El-Hachem, Batoul Dekmak, Humam Kadara, Georges Nemer. Role of the evolutionarily conserved TBX2 subfamily of transcription factors in the molecular pathogenesis of human lung adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5513.

This paper describes a new problem of digital circuit design-redesign of digital VLSI circuits with incomplete implementation information-and presents a solution-redesign process. Efficient algorithms are developed to derive the transfer functions of the portion with incomplete implementation information. Thus, the portion can be reimplemented using the derived transfer functions. We do not intend to discover the exact circuit schematic and components that were present in the circuit originally implemented. Rather, the functions originally intended to be present will be identical. A set of simple rules is proposed in this study to quickly analyze the redesignability of a target circuit.