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Coronary artery disease (CAD) is a syndrome resulting from myocardial ischaemia of heterogeneous pathomechanism. Environmental and genetic factors contribute to its development. Atherosclerotic plaques that significantly narrow the lumen of coronary arteries cause symptoms of myocardial ischaemia. Acute coronary incidents are most often associated with plaque rupture or erosion accompanied by local activation of the coagulation system with thrombus formation. Plaque formation and stability are influenced by endothelial function and vascular smooth muscle cell function. In this study, we investigated the association between polymorphisms in genes affecting endothelial and vascular smooth muscle cell (VSMC) function and the occurrence of unstable angina pectoris. The aim of this study was to evaluate the association between the Show less

Metabolic syndrome (MetS) amplifies the risks of atherosclerosis. Despite well-known sexual dimorphism in atherosclerosis, underlying mechanisms are poorly understood. Our previous findings highlight a proatherogenic protein, thrombospondin-1 (TSP-1), in hyperglycemia- or hyperleptinemia (mimicking obesity)-induced atherosclerosis. However, the role of TSP-1 in the development of atherosclerosis prompted by co-existing hyperglycemia and obesity, characteristic of MetS, is unknown. The goal of this study was to examine sex-specific differences in lesion progression in a model of combined MetS and atherosclerosis (KKAyApoE) and interrogate how these differences relate to TSP-1 expression. Male and female KKAy Metabolic profiling confirmed MetS phenotype of KKAy Together, the current study implicates a role of plasma testosterone in sex-specific differences in atherosclerosis and TSP-1 expression in MetS vs non-MetS mice. Our data suggest a sex-dependent differential role of TSP-1 on SMC de-differentiation in MetS. Collectively, these findings underscore a fundamental link between TSP-1 and VSMC phenotypic transformation in MetS. Show less

The prognosis of patients with advanced arteriosclerosis is bleak due to the lack of understanding of arteriosclerosis. Epigenetics-based DNA methylation plays an important role in the pathogenesis of arteriosclerosis. Hence, we aimed to identify the epigenetics-related aberrantly methylated differentially expressed genes (AMDEGs) in arteriosclerosis. A gene expression dataset and DNA methylation dataset were downloaded from the Gene Expression Omnibus database, and AMDEGs were identified on the basis of the relationship between methylation and expression. Subsequently, the expression levels of candidate hub genes were detected in human peripheral blood mononuclear cells (PBMCs) from atherosclerotic patients and control subjects by RT-qPCR and Western blot. Lastly, the methylation level of the target gene was detected using the MassARRAY method. In the present study, the hypermethylated and downregulated genes were mainly involved in vascular smooth muscle contraction. The hypomethylated and upregulated genes were markedly associated with immune-inflammatory processes. Following validation, LMOD1 was identified as the target gene, which was hypermethylated and downregulated in arteriosclerosis. The methylation levels of CpG sites in LMOD1 promoter were detected to be elevated in the PBMCs of atherosclerotic patients. In conclusion, AMDEGs identified in the present study may assist in understanding the pathogenesis of arteriosclerosis. LMOD1 exhibits potential as a promising diagnostic and therapeutic biomarker for arteriosclerosis. Show less

Smooth muscle disorders affecting both the intestine and the bladder have been known for a decade. However, the recent discovery of genes associated with these dysfunctions has led to the description of several clinical phenotypes. We performed a systematic review of all published cases involving seven genes with pathogenic variants, Show less

The Lauren classification of gastric tumors strongly correlates with prognosis. The purpose of this study was to explore the specific molecular mechanism of Lauren classification of gastric cancer and provide a possible theoretical basis for the treatment of gastric cancer. We standardized the gene expression data of five Gene Expression Omnibus gastric cancer databases and constructed a Weighted Co-expression Network Analysis (WGCNA) model based on clinicopathological information. The overall survival (OS) and disease-free survival (DFS) curves were extracted from the Cancer Genome Atlas (TCGA) and GSE62254 databases. Western blotting was used to measure protein expression in cells and tissues. Scratch and transwell experiments were used to test the migration ability of tumor cells. Immunohistochemistry was used to measure tissue protein expression in clinical tissue samples to correlate to survival data. The WGCNA model demonstrated that blue cyan was highly correlated with the Lauren classification of the tumor (r = 0.24, P = 7 × 10 LMOD1 is an oncogene associated with diffuse gastric cancer and can affect the occurrence and development of EMT by regulating the FAK-Akt/mTOR pathway. LMOD1 can therefore promote peritoneal metastasis of gastric cancer cells and can be used as a novel therapeutic target for gastric cancer. Show less

Recently, studies on competing endogenous RNA (ceRNA) networks have become prevalent, and circular RNAs (circRNAs) have crucial implications for the development and progression of carcinoma. However, studies relevant to metastatic prostate cancer (mPCa) are scant. This study aims to discover potential ceRNAs that may be related to the prognosis of mPCa. RNA-Seq data were obtained from the MiOncoCirc database and Gene Expression Omnibus (GEO). Differential expression patterns of RNAs were examined using R packages. Circular RNA Interactome, miRTarBase, miRDB and TargetScan were applied to predict the corresponding relation between circRNAs, miRNAs and mRNAs. The Gene Ontology (GO) annotations were performed to present related GO terms, and Gene Set Enrichment Analysis (GSEA) tools were applied for pathway annotations. Moreover, survival analysis was conducted for the hub genes. We found 820 circRNAs, 81 miRNAs and 179 mRNAs that were distinguishingly expressed between primary prostate cancer (PCa) and mPCa samples. A ceRNA network including 45 circRNAs, 24 miRNAs and 56 mRNAs was constructed. In addition, the protein-protein interaction (PPI) network was built, and 10 hub genes were selected by using the CytoHubba application. Among the 10 hub genes, survival analysis showed that ITGA1, LMOD1, MYH11, MYLK, SORBS1 and TGFBR3 were significantly connected with disease-free survival (DFS). The circRNA-mediated ceRNA network provides potential prognostic biomarkers for metastatic prostate cancer. Show less

Aging acts as a dominating risk factor for human cancers. Herein, we systematically dissected the features of transcriptional aging-relevant genes in gastric cancer from multiple perspectives. Based on the transcriptome profiling of prognostic aging-relevant genes, patients with gastric cancer in The Cancer Genome Atlas (TCGA) stomach adenocarcinoma (TCGA-STAD) cohort were clustered with a consensus clustering algorithm. Mutational landscape and chemotherapeutic responses were analyzed and immunological features (immunomodulators, immune checkpoint molecules, cancer immunity cycle, and tumor-infiltrating immune cells) were systematically evaluated across gastric cancer. Weighted gene co-expression network (WGCNA) was conducted for screening aging molecular phenotype-relevant genes, and key genes were identified with Molecular Complex Detection (MCODE) analyses. Expressions of key genes were examined in 20 paired tumors and controls with RT-qPCR and Western blotting. Proliferation and apoptosis were investigated in two gastric cancer cells under MYL9 deficiency. Three aging-based molecular phenotypes (namely, C1, C2, and C3) were conducted in gastric cancer. Phenotype C1 presented the most prominent survival advantage and highest mutational frequencies. Phenotype C2 indicated low responses to sorafenib and gefitinib, while C3 indicated low responses to vinorelbine and gemcitabine. Additionally, phenotype C2 was characterized by enhanced immune and stromal activation and an inflamed tumor microenvironment. Seven aging molecular phenotype-relevant key genes (ACTA2, CALD1, LMOD1, MYH11, MYL9, MYLK, and TAGLN) were identified, which were specifically upregulated in tumors and in relation to dismal prognosis. Among them, MYL9 deficiency reduced proliferation and enhanced apoptosis in gastric cancer cells. Collectively, aging-based molecular subtypes may offer more individualized therapy recommendations and prognosis assessment for patients in distinct subtypes. Show less

The diameter of the abdominal aortic aneurysm (AAA) is the most commonly used parameter for the prediction of occurrence of AAA rupture. However, the most vulnerable region of the aortic wall may be different from the most dilated region of AAA under pressure. The present study is the first to use weighted gene coexpression network analysis (WGCNA) to detect the coexpressed genes that result in regional weakening of the aortic wall. The GSE165470 raw microarray dataset was used in the present study. Differentially expressed genes (DEGs) were filtered using the "limma" R package. DEGs were assessed by Gene Ontology biological process (GO-BP) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. WGCNA was used to construct the coexpression networks in the samples with regional weakening of the AAA wall and in the control group to detect the gene modules. The hub genes were defined in the significant functional modules, and a hub differentially expressed gene (hDEG) coexpression network was constructed with the highest confidence based on protein-protein interactions (PPIs). Molecular compound detection (MCODE) was used to identify crucial genes in the hDEG coexpression network. Crucial genes in the hDEG coexpression network were validated using the GSE7084 and GSE57691 microarray gene expression datasets. A total of 350 DEGs were identified, including 62 upregulated and 288 downregulated DEGs. The pathways were involved in immune responses, vascular smooth muscle contraction and cell-matrix adhesion of DEGs in the samples with regional weakening in AAA. Antiquewhite3 was the most significant module and was used to identify downregulated hDEGs based on the result of the most significant modules negatively related to the trait of weakened aneurysm walls. Seven crucial genes were identified and validated: ACTG2, CALD1, LMOD1, MYH11, MYL9, MYLK, and TPM2. These crucial genes were associated with the mechanisms of AAA progression. We identified crucial genes that may play a significant role in weakening of the AAA wall and may be potential targets for medical therapies and diagnostic biomarkers. Further studies are required to more comprehensively elucidate the functions of crucial genes in the pathogenesis of regional weakening in AAA. Show less

Megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS), or "visceral myopathy," is a severe early onset disorder characterized by impaired muscle contractility in the bladder and intestines. Five genes are linked to MMIHS: primarily ACTG2, but also LMOD1, MYH11, MYLK, and MYL9. Here we describe a three-year-old girl with bilateral hydronephrosis diagnosed at 20 weeks gestation and congenital mydriasis (both of which have been previously observed among individuals with MMIHS). A clinical diagnosis of MMIHS was made based upon the presence of megacystis, lack of urinary bladder peristalsis, and intestinal pseudo-obstruction. After initial testing of ACTG2 was negative, further sequencing and deletion/duplication testing was performed on the LMOD1, MYH11,MYLK, and MYL9 genes. We identified two heterozygous loss of function variants in MYL9: an exon 4 deletion and a nine base pair deletion that removes the canonical splicing donor site at exon 2 (NM₀₀₆₀₉₇.5:c.184+2₁₈₄₊₁₀del). Parental testing confirmed these variants to be in trans in our proband. To our knowledge, only one other individual with MMIHS has biallelic mutations in MYL9 (a homozygous deletion encompassing exon 4). We suggest MYL9 be targeted on genetic testing panels for MMIHS, smooth muscle myopathies, and cardiovascular phenotypes. Show less

Megacystis-microcolon-intestinal-hypoperistalsis syndrome (MMIHS) is a severe congenital visceral myopathy characterized by an abdominal distension due to a large non-obstructed urinary bladder, a microcolon and intestinal hypo- or aperistalsis. Most of the patients described to date carry a sporadic heterozygous variant in ACTG2. More recently, recessive forms have been reported and mutations in MYH11, LMOD1, MYLK and MYL9 have been described at the molecular level. In the present report, we describe five patients carrying a recurrent heterozygous variant in ACTG2. Exome sequencing performed in four families allowed us to identify the genetic cause in three. In two families, we identified variants in MMIHS causal genes, respectively a nonsense homozygous variant in MYH11 and a previously described homozygous deletion in MYL9. Finally, we identified compound heterozygous variants in a novel candidate gene, PDCL3, c.[143₁₄₄del];[380G>A], p.[(Tyr48Ter)];[(Cys127Tyr)]. After cDNA analysis, a complete absence of PDLC3 expression was observed in affected individuals, indicating that both mutated transcripts were unstable and prone to mediated mRNA decay. PDCL3 encodes a protein involved in the folding of actin, a key step in thin filament formation. Presumably, loss-of-function of this protein affects the contractility of smooth muscle tissues, making PDCL3 an excellent candidate gene for autosomal recessive forms of MMIHS. Show less

Proprotein convertases (PCSKs) process matrix metalloproteases and cytokines, but their function in the vasculature is largely unknown. Previously, we demonstrated upregulation of PCSK6 in atherosclerotic plaques from symptomatic patients, localization to smooth muscle cells (SMCs) in the fibrous cap and positive correlations with inflammation, extracellular matrix remodeling and cytokines. Here, we hypothesize that PCSK6 could be involved in flow-mediated vascular remodeling and aim to evaluate its role in the physiology of this process using knockout mice. Pcsk6 Show less

A label-free proteomics method was used to explore the effects of differentially expressed proteins on the tenderness of yak rumen smooth muscle during postmortem storage (0, 3 and 7 days) at 3 ± 1 °C. The tenderness improved significantly during storage. A total of 212 differentially expressed proteins were identified by the following comparisons: Day 3 vs.0, day 7 vs.0, and day 7 vs.3. Twenty-eight proteins were correlated with the WBSF of yak rumen smooth muscle. Calpastatin, ADP/ATP translocase 1, zyxin, LMOD1 protein, tropomyosin α-3 chain, thrombospondin-4 and UQCRC1 protein are highly related to smooth muscle tenderness, and thus, they are candidates indicators of yak rumen smooth muscle tenderness during storage. Furthermore, bioinformatics analyses revealed that the identified proteins were related to focal adhesion, vascular smooth muscle contraction, cardiac muscle contraction and necroptosis. The present results could provide proteomic insights into changes in yak rumen smooth muscle tenderness during storage and may be a valuable resource for future investigations. Show less

Megacystis-microcolon-intestinal-hypoperistalsis syndrome (MMIHS) is a rare and severe disorder characterized by functional obstruction in the urinary and gastrointestinal tract. The molecular basis of this condition has been defined recently. Heterozygous variants in ACTG2, homozygous mutations in LMOD1, MYLK, and MYH9 were related to the pathogenesis of the syndrome, which encodes proteins involved in the process of smooth muscle contraction, supporting a myopathic basis for the disease. Recent studies have identified homozygous or compound heterozygous variants in MYH11 as a candidate gene of MMIHS. In this report, we described a nonconsanguineous Chinese family with three male fetuses affected with megacystis. Trio-targeted exome sequencing identified compound heterozygous variants, c.2051 G > A (p.R684H) and c.3540₃₅₄₁delinsTT (p.(E1180D, Q1181Ter)), in MYH11 (NM₀₀₁₀₄₀₁₁₄₎. The variants were inherited from the parents, respectively. Western blotting showed a marked decrease in MYH11 protein in the proband's umbilical cord tissue compared with the control sample. The study's results confirmed that MYH11 is a candidate gene for MMIHS with autosomal recessive (AR) inheritance and expanded the mutation spectrum for this clinical condition. Combining clinical phenotype with molecular diagnosis may enable the identification of candidate genes for potential monogenic diseases and facilitate accurate genetic counseling, informed decision-making, and prenatal diagnosis. Show less

Chronic Intestinal Pseudo-Obstruction (CIPO) is a rare gastrointestinal disorder, which affects the smooth muscle contractions of the gastrointestinal tract. Dominant mutations in the smooth muscle actin gene, ACTG2, accounts for 44%-50% of CIPO patients. Other recessive or X-linked genes, including MYLK, LMOD1, RAD21, MYH11, MYL9, and FLNA were reported in single cases. In this study, we used Whole-Exome Sequencing (WES) to study 23 independent CIPO families including one extended family with 13 affected members. A dominantly inherited rare mutation, c.5819delC (p.Pro1940HisfsTer91), in the smooth muscle myosin gene, MYH11, was found in the extended family, shared by 7 affected family members but not by 3 unaffected family members with available DNA, suggesting a high probability of genetic linkage. Gene burden analysis indicates that additional genes, COL4A1, FBLN1 and HK2, may be associated with the disease. This study expanded our understanding of CIPO etiology and provided additional genetic evidence to physicians and genetic counselors for CIPO diagnosis. Show less

Intracranial aneurysm (IA) represents a cerebrovascular disorder that featured by dilation or bulging of the weakened blood vessel wall. When it ruptures, an IA leads to subarachnoid hemorrhage with high disability and mortality rates. Despite the numerous studies focusing on IA ruptures, little research on IA pathogenesis has been reported. In this study, we aimed to reveal key genes related to IA formation. Four datasets from Gene Expression Omnibus data were downloaded, normalized, and separated into the IA group and the normal vessel control group for analyses. We screened for differentially expressed genes (DEGs) between groups and conducted functional enrichment, pathway enrichment, and gene set enrichment analysis analyses among significant DEGs. according to our analyses, significant DEGs majorly associate with smooth muscle system and the complement system. Among all DEGs, 5 down-regulated genes (MYH11, CNN1, MYOCD, ACTA1, and LMOD1) and 3 up-regulated genes (C1QB, C3AR1, and VSIG4) are most relevant in IA formation. Key DEGs identified in this study are related to IA pathogenesis. Among identified DEGs, LMOD1 is the most significant and merits more attention. Show less

This study was designed to identify the potential key protein interaction networks, genes, and correlated pathways in early-onset colorectal cancer (CRC) via bioinformatics methods. We selected microarray data GSE4107 consisting 12 patient's colonic mucosa and 10 healthy control mucosa; initially, the GSE4107 were downloaded and analyzed using limma package to identify differentially expressed genes (DEGs). A total of 131 DEGs consisting of 108 upregulated genes and 23 downregulated genes of patients in early-onset CRC were selected by the criteria of adjusted P values <.01 and |log2 fold change (FC)| ≥ 2. The gene ontology functional enrichment analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were accomplished to view the biological process, cellular components, molecular function, and the KEGG pathways of DEGs. Finally, protein-protein interactions (PPIs) were constructed, and the hub protein module was identified. Genes such as ACTA2, ACTG2, MYH11, CALD1, MYL9, TPM2, and LMOD1 were strongly implicated in CRC. In summary, in this study, we indicated that molecular mechanisms were involved in muscle contraction and vascular smooth muscle contraction signaling pathway, which improve our understanding of CRC and could be used as new therapeutic targets for CRC. Show less

The purpose of this review is to discuss current knowledge on pediatric intestinal pseudo-obstruction. We will also review new mutations that have been identified through advancement in genetic testing, allowing for a better understanding of the underlying mechanisms of intestinal dysmotility and potential etiologies. With the advancements in genetic testing, new mutations have been identified in the diagnosis of megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS), a disorder leading to pediatric pseudo-obstruction. MYLK, LMOD1, MYL9, and MYH11 encode for various proteins within smooth muscle cells; abnormalities within these proteins lead to abnormal intestinal smooth muscle contractions. Chronic intestinal pseudo-obstruction (CIPO) is defined by symptoms of bowel obstruction in the absence of a lumen-occluding lesion. CIPO is a heterogeneous group of disorders caused by abnormalities in the enteric neurons, intestinal smooth muscle, and/or the interstitial cells of Cajal (ICC). Symptoms can be non-specific and etiologies include both primary and secondary causes of CIPO that contribute to the delay in recognizing this condition and making the correct diagnosis. Chronic intestinal pseudo-obstruction has been recognized in both adults and children with fundamental differences in the etiology, symptom onset, clinical features and natural history of this disorder. For this reason, it has been considered a separate entity referred to as pediatric intestinal pseudo-obstruction (PIPO). Show less

The histology-based Gleason score (GS) of prostate cancer (PCa) tissue biopsy is the most accurate predictor of disease aggressiveness and an important measure to guide treatment strategies and patient management. The variability associated with PCa tumor sampling and the subjective determination of the GS are challenges that limit accurate diagnostication and prognostication. Thus, novel molecular signatures are needed to distinguish between indolent and aggressive forms of PCa for better patient management and outcomes. Herein, label-free LC-MS/MS proteomics is used to profile the proteome of 50 PCa tissues spanning five grade groups (n = 10 per group) relative to tissues from individuals with benign prostatic hyperplasia (BPH). Over 2000 proteins are identified albeit at different levels between and within the patient groups, revealing biological processes associated with specific grades. A panel of 11 prostate-derived proteins including IGKV3D-20, RNASET2, TACC2, ANXA7, LMOD1, PRCP, GYG1, NDUFV1, H1FX, APOBEC3C, and CTSZ display the potential to stratify patients from low and high PCa grade groups. Parallel reaction monitoring of the same sample cohort validate the differential expression of LMOD1, GYG1, IGKV3D-20, and RNASET2. The four proteins associated with low and high PCa grades reported here warrant further exploration as candidate biomarkers for PCa aggressiveness. Show less

Neonatal heart failure is a rare, poorly-understood presentation of familial dilated cardiomyopathy (DCM). Exome sequencing in a neonate with severe DCM revealed a homozygous nonsense variant in leiomodin 2 ( Show less

Megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIHS) is a severe disease characterized by functional obstruction in the urinary and gastrointestinal tract. The molecular basis of this condition started to be defined recently, and the genes related to the syndrome (ACTG2-heterozygous variant in sporadic cases; and MYH11 (myosin heavy chain 11), LMOD1 (leiomodin 1) and MYLK (myosin light chain (MLC) kinase)-autosomal recessive inheritance), encode proteins involved in the smooth muscle contraction, supporting a myopathic basis for the disease. In the present article, we described a family with two affected siblings with MMIHS born to consanguineous parents and the molecular investigation performed to define the genetic etiology. Previous whole exome sequencing of the affected child and parents did not identify a candidate gene for the disease in this family, but now we present a reanalysis of the data that led to the identification of a homozygous deletion encompassing the last exon of MYL9 (myosin regulatory light chain 9) in the affected individual. MYL9 gene encodes a regulatory myosin MLC and the phosphorylation of this protein is a crucial step in the contraction process of smooth muscle cell. Despite the absence of human or animal phenotype related to MYL9, a cause-effect relationship between MYL9 and the MMIHS seems biologically plausible. The present study reveals a strong candidate gene for autosomal recessive forms of MMIHS, expanding the molecular basis of this disease and reinforces the myopathic basis of this condition. Show less

Primary chronic intestinal pseudo-obstruction (CIPO) is a rare, potentially life-threatening disorder characterized by severely impaired gastrointestinal motility. The objective of this study was to examine the contribution of ACTG2, LMOD1, MYH11, and MYLK mutations in an Australasian cohort of patients with a diagnosis of primary CIPO associated with visceral myopathy. Pediatric and adult patients with primary CIPO and suspected visceral myopathy were recruited from across Australia and New Zealand. Sanger sequencing of the genes encoding enteric gamma-actin (ACTG2) and smooth muscle leiomodin (LMOD1) was performed on DNA from patients, and their relatives, where available. MYH11 and MYLK were screened by next-generation sequencing. We identified heterozygous missense variants in ACTG2 in 7 of 17 families (~41%) diagnosed with CIPO and its associated conditions. We also identified a previously unpublished missense mutation (c.443C>T, p.Arg148Leu) in one family. One case presented with megacystis-microcolon-intestinal hypoperistalsis syndrome in utero with subsequent termination of pregnancy at 28 weeks' gestation. All of the substitutions identified occurred at arginine residues. No likely pathogenic variants in LMOD1, MYH11, or MYLK were identified within our cohort. ACTG2 mutations represent a significant underlying cause of primary CIPO with visceral myopathy and associated phenotypes in Australasian patients. Thus, ACTG2 sequencing should be considered in cases presenting with hypoperistalsis phenotypes with suspected visceral myopathy. It is likely that variants in other genes encoding enteric smooth muscle contractile proteins will contribute further to the genetic heterogeneity of hypoperistalsis phenotypes. Show less

Genome-wide association studies have identified multiple loci associated with coronary artery disease and myocardial infarction, but only a few of these loci are current targets for on-market medications. To identify drugs suitable for repurposing and their targets, we created 2 unique pipelines integrating public data on 49 coronary artery disease/myocardial infarction-genome-wide association studies loci, drug-gene interactions, side effects, and chemical interactions. We first used publicly available genome-wide association studies results on all phenotypes to predict relevant side effects, identified drug-gene interactions, and prioritized candidates for repurposing among existing drugs. Second, we prioritized gene product targets by calculating a druggability score to estimate how accessible pockets of coronary artery disease/myocardial infarction-associated gene products are, then used again the genome-wide association studies results to predict side effects, excluded loci with widespread cross-tissue expression to avoid housekeeping and genes involved in vital processes and accordingly ranked the remaining gene products. These pipelines ultimately led to 3 suggestions for drug repurposing: pentolinium, adenosine triphosphate, and riociguat (to target CHRNB4, ACSS2, and GUCY1A3, respectively); and 3 proteins for drug development: LMOD1 (leiomodin 1), HIP1 (huntingtin-interacting protein 1), and PPP2R3A (protein phosphatase 2, regulatory subunit b-double prime, α). Most current therapies for coronary artery disease/myocardial infarction treatment were also rediscovered. Integration of genomic and pharmacological data may prove beneficial for drug repurposing and development, as evidence from our pipelines suggests. Show less

Recent genome-wide association studies (GWAS) have identified multiple new loci which appear to alter coronary artery disease (CAD) risk via arterial wall-specific mechanisms. One of the annotated genes encodes LMOD1 (Leiomodin 1), a member of the actin filament nucleator family that is highly enriched in smooth muscle-containing tissues such as the artery wall. However, it is still unknown whether LMOD1 is the causal gene at this locus and also how the associated variants alter LMOD1 expression/function and CAD risk. Using epigenomic profiling we recently identified a non-coding regulatory variant, rs34091558, which is in tight linkage disequilibrium (LD) with the lead CAD GWAS variant, rs2820315. Herein we demonstrate through expression quantitative trait loci (eQTL) and statistical fine-mapping in GTEx, STARNET, and human coronary artery smooth muscle cell (HCASMC) datasets, rs34091558 is the top regulatory variant for LMOD1 in vascular tissues. Position weight matrix (PWM) analyses identify the protective allele rs34091558-TA to form a conserved Forkhead box O3 (FOXO3) binding motif, which is disrupted by the risk allele rs34091558-A. FOXO3 chromatin immunoprecipitation and reporter assays show reduced FOXO3 binding and LMOD1 transcriptional activity by the risk allele, consistent with effects of FOXO3 downregulation on LMOD1. LMOD1 knockdown results in increased proliferation and migration and decreased cell contraction in HCASMC, and immunostaining in atherosclerotic lesions in the SMC lineage tracing reporter mouse support a key role for LMOD1 in maintaining the differentiated SMC phenotype. These results provide compelling functional evidence that genetic variation is associated with dysregulated LMOD1 expression/function in SMCs, together contributing to the heritable risk for CAD. Show less

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a congenital disorder characterized by loss of smooth muscle contraction in the bladder and intestine. To date, three genes are known to be involved in MMIHS pathogenesis: ACTG2, MYH11, and LMOD1. However, for approximately 10% of affected individuals, the genetic cause of the disease is unknown, suggesting that other loci are most likely involved. Here, we report on three MMIHS-affected subjects from two consanguineous families with no variants in the known MMIHS-associated genes. By performing homozygosity mapping and whole-exome sequencing, we found homozygous variants in myosin light chain kinase (MYLK) in both families. We identified a 7 bp duplication (c.3838₃₈₄₄dupGAAAGCG [p.Glu1282_Glyfs Show less

Megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS) is a congenital visceral myopathy characterized by severe dilation of the urinary bladder and defective intestinal motility. The genetic basis of MMIHS has been ascribed to spontaneous and autosomal dominant mutations in actin gamma 2 ( Show less

Coronary artery disease (CAD) is a leading cause of morbidity and mortality worldwide. Although 58 genomic regions have been associated with CAD thus far, most of the heritability is unexplained, indicating that additional susceptibility loci await identification. An efficient discovery strategy may be larger-scale evaluation of promising associations suggested by genome-wide association studies (GWAS). Hence, we genotyped 56,309 participants using a targeted gene array derived from earlier GWAS results and performed meta-analysis of results with 194,427 participants previously genotyped, totaling 88,192 CAD cases and 162,544 controls. We identified 25 new SNP-CAD associations (P < 5 × 10 Show less

Uterine leiomyosarcoma (ULMS) is an aggressive form of soft tissue tumors. The molecular heterogeneity and pathogenesis of ULMS are not well understood. Expression profiling data were used to determine the possibility and optimal number of ULMS molecular subtypes. Next, clinicopathological characters and molecular pathways were analyzed in each subtype to prospect the clinical applications and progression mechanisms of ULMS. Two distinct molecular subtypes of ULMS were defined based on different gene expression signatures. Subtype I ULMS recapitulated low-grade ULMS, the gene expression pattern of which resembled normal smooth muscle cells, characterized by overexpression of smooth muscle function genes such as LMOD1, SLMAP, MYLK, MYH11. In contrast, subtype II ULMS recapitulated high-grade ULMS with higher tumor weight and invasion rate, and was characterized by overexpression of genes involved in the pathway of epithelial to mesenchymal transition and tumorigenesis, such as CDK6, MAPK13 and HOXA1. We identified two distinct molecular subtypes of ULMS responding differently to chemotherapy treatment. Our findings provide a better understanding of ULMS intrinsic molecular subtypes, and will potentially facilitate the development of subtype-specific diagnosis biomarkers and therapy strategies for these tumors. Show less

Leiomodins (Lmods) are a family of actin filament nucleators related to tropomodulins (Tmods), which are pointed end-capping proteins. Whereas Tmods have alternating tropomyosin- and actin-binding sites (TMBS1, ABS1, TMBS2, ABS2), Lmods lack TMBS2 and half of ABS1, and present a C-terminal extension containing a proline-rich domain and an actin-binding Wiskott-Aldrich syndrome protein homology 2 (WH2) domain that is absent in Tmods. Most of the nucleation activity of Lmods resides within a fragment encompassing ABS2 and the C-terminal extension. This fragment recruits actin monomers into a polymerization nucleus. Here, we revise a recently reported structure of this region of Lmod2 in complex with actin and provide biochemical validation for the newly revised structure. We find that instead of two actin subunits connected by a single Lmod2 polypeptide, as reported in the original structure, the P1 unit cell contains two nearly identical copies of actin monomers, each bound to Lmod2's ABS2 and WH2 domain, with no electron density connecting these two domains. Moreover, we show that the two actin molecules in the unit cell are related to each other by a local twofold noncrystallographic symmetry axis, a conformation clearly distinct from that of actin subunits in the helical filament. We further find that a proposed actin-binding site within the missing connecting region of Lmod2, termed helix h1, does not bind actin in vitro and that the electron density assigned to it in the original structure corresponds instead to a WH2 domain with opposite backbone directionality. Polymerization assays using Lmod2 mutants of helix h1 and the WH2 domain support this conclusion. Finally, we find that deleting the C-terminal extension of Lmod1 and Lmod2 results in an approximately threefold decrease in the nucleation activity, which is only partially accounted for by the lack of the WH2 domain. Show less

Prostatic smooth muscle cells (pSMCs) differentiation is a key factor for prostatic homeostasis, with androgens exerting multiple effects on these cells. Here, we demonstrated that the myodifferentiator complex Srf/Myocd is up-regulated by testosterone in a dose-dependent manner in primary cultures of rat pSMCs, which was associated to the increase in Acta2, Cnn1, and Lmod1 expressions. Blocking Srf or Myocd by siRNAs inhibited the myodifferentiator effect of testosterone. While LPS led to a dedifferentiated phenotype in pSMCs, characterized by down-regulation of Srf/Myocd and smooth muscle cell (SMC)-restricted genes, endotoxin treatment on Myocd-overexpressing cells did not result in phenotypic alterations. Testosterone at a physiological dose was able to restore the muscular phenotype by normalizing Srf/Myocd expression in inflammation-induced dedifferentiated pSMCs. Moreover, the androgen reestablished the proliferation rate and IL-6 secretion increased by LPS. These results provide novel evidence regarding the myodifferentiating role of testosterone on SMCs by modulating Srf/Myocd. Thus, androgens preserve prostatic SMC phenotype, which is essential to maintain the normal structure and function of the prostate. J. Cell. Physiol. 232: 2806-2817, 2017. © 2016 Wiley Periodicals, Inc. Show less