MiR-147b influences vascular smooth muscle cell proliferation and migration via targeting YY1 and modulating Wnt/β-catenin activities

[Expression of soluble factor-related apoptosis ligand in peripheral blood and microRNA-147b in monocytes in children with sepsis and their association with prognosis]

OBJECTIVES

To investigate the expression of soluble factor-related apoptosis ligand (sFasL) in peripheral blood and microRNA-147b (miR-147b) in monocytes in children with sepsis and their value in assessing prognosis.

METHODS

A prospective study was conducted on 124 children with sepsis (sepsis group), 60 children with common infections (infection group), and 60 healthy children undergoing physical examinations (healthy control group). The independent risk factors for poor prognosis in children with sepsis were analyzed, and the value of serum sFasL and monocyte miR-147b in predicting poor prognosis in children with sepsis was assessed.

RESULTS

The serum level of sFasL and the relative expression of miR-147b in monocytes were highest in the sepsis group, followed by the infection group and the healthy control group (P<0.05). The multivariate logistic regression analysis showed that the serum level of sFasL and the relative expression of miR-147b in monocytes were closely associated with the poor prognosis of children with sepsis (P<0.05). The receiver operating characteristic curve analysis showed that the combination of serum sFasL level and relative expression of miR-147b in monocytes had a larger area under the curve compared to each indicator alone in predicting the prognosis of children with sepsis (P<0.05).

CONCLUSIONS

There are significant increases in the level of sFasL in peripheral blood and the relative expression of miR-147b in monocytes in children with sepsis. The combined use of these two indicators has relatively high clinical value in assessing the prognosis of children with sepsis.

Targeting PDGF/PDGFR Signaling Pathway by microRNA, lncRNA, and circRNA for Therapy of Vascular Diseases: A Narrow Review

Despite the significant progress in diagnostic and therapeutic strategies, vascular diseases, such as cardiovascular diseases (CVDs) and respiratory diseases, still cannot be successfully eliminated. Vascular cells play a key role in maintaining vascular homeostasis. Notably, a variety of cells produce and secrete platelet-derived growth factors (PDGFs), which promote mitosis and induce the division, proliferation, and migration of vascular cells including vascular smooth muscle cells (SMCs), aortic SMCs, endothelial cells, and airway SMCs. Therefore, PDGF/PDGR receptor signaling pathways play vital roles in regulating the homeostasis of blood vessels and the onset and development of CVDs, such as atherosclerosis, and respiratory diseases including asthma and pulmonary arterial hypertension. Recently, accumulating evidence has demonstrated that microRNA, long-chain non-coding RNA, and circular RNA are involved in the regulation of PDGF/PDGFR signaling pathways through competitive interactions with target mRNAs, contributing to the occurrence and development of the above-mentioned diseases. These novel findings are useful for laboratory research and clinical studies. The aim of this article is to conclude the recent progresses in this field, particular the mechanisms of action of these non-coding RNAs in regulating vascular remodeling, providing potential strategies for the diagnosis, prevention, and treatment of vascular-dysfunction-related diseases, particularly CVDs and respiratory diseases.

Unraveling the miRNA Puzzle in Atherosclerosis: Revolutionizing Diagnosis, Prognosis, and Therapeutic Approaches

PURPOSE OF REVIEW

To eradicate atherosclerotic diseases, novel biomarkers, and future therapy targets must reveal the burden of early atherosclerosis (AS), which occurs before life-threatening unstable plaques form. The chemical and biological features of microRNAs (miRNAs) make them interesting biomarkers for numerous diseases. We summarized the latest research on miRNA regulatory mechanisms in AS progression studies, which may help us use miRNAs as biomarkers and treatments for difficult-to-treat diseases.

RECENT FINDINGS

Recent research has demonstrated that miRNAs have a regulatory function in the observed changes in gene and protein expression during atherogenesis, the process that leads to atherosclerosis. Several miRNAs play a role in the development of atherosclerosis, and these miRNAs could potentially serve as non-invasive biomarkers for atherosclerosis in various regions of the body. These miRNAs have the potential to serve as biomarkers and targets for early treatment of atherosclerosis. The start and development of AS require different miRNAs. It reviews new research on miRNAs affecting endothelium, vascular smooth muscle, vascular inflammation, lipid retention, and cholesterol metabolism in AS. A miRNA gene expression profile circulates with AS everywhere. AS therapies include lipid metabolism, inflammation reduction, and oxidative stress inhibition. Clinical use of miRNAs requires tremendous progress. We think tiny miRNAs can enable personalized treatment.

Serum miRNA profiling identified miRNAs associated with disease severity in psoriasis

Psoriasis vulgaris is a chronic, autoimmune skin disease involving a complex interplay of epidermal keratinocytes, dermal fibroblast and infiltrating immune cells. Differential expressions of miRNAs are observed in psoriasis and the deregulated miRNAs are sometimes associated with disease severity. This study aims to identify miRNAs altered in the serum of psoriasis patients that are associated with the Psoriasis Area and Severity Index (PASI). In order to assess miRNA levels in the serum of psoriasis patients, we selected 24 differentially expressed miRNAs in the psoriatic skin are possibly derived from the skin and immune cells, as well as five miRNAs that are enriched in other tissues. We identified 16 miRNAs that exhibited significantly (p < 0.05) altered levels in the serum of psoriasis patients compared to healthy individuals. Among these, 13 miRNAs showed similar expression pattern in the serum of psoriasis patients as also observed in the psoriatic skin tissues. Ten miRNAs showed an accuracy of greater than 75% in classifying the psoriasis patients from healthy individuals. Further analysis of differential miRNA levels between the low PASI group and the high PASI group identified three miRNAs (miR-147b, miR-3614-5p, and miR-125a-5p) with significantly altered levels between the low severity and the high severity psoriasis patients. Our systematic investigation of skin and immune cell-derived miRNAs in the serum of psoriasis patients revealed alteration in miRNA levels to be associated with disease severity, which may help in monitoring the disease progression and therapeutic response.

Deletion of Smooth Muscle O-GlcNAc Transferase Prevents Development of Atherosclerosis in Western Diet-Fed Hyperglycemic ApoE-/- Mice In Vivo

Accumulating evidence highlights protein O-GlcNAcylation as a putative pathogenic contributor of diabetic vascular complications. We previously reported that elevated protein O-GlcNAcylation correlates with increased atherosclerotic lesion formation and VSMC proliferation in response to hyperglycemia. However, the role of O-GlcNAc transferase (OGT), regulator of O-GlcNAc signaling, in the evolution of diabetic atherosclerosis remains elusive. The goal of this study was to determine whether smooth muscle OGT (smOGT) plays a direct role in hyperglycemia-induced atherosclerotic lesion formation and SMC de-differentiation. Using tamoxifen-inducible Myh11-CreERT2 and Ogtfl/fl mice, we generated smOGTWT and smOGTKO mice, with and without ApoE-null backgrounds. Following STZ-induced hyperglycemia, smOGTWT and smOGTKO mice were kept on a standard laboratory diet for the study duration. In a parallel study, smOGTWTApoE-/- and smOGTKOApoE-/- were initiated on Western diet at 8-wks-age. Animals harvested at 14-16-wks-age were used for plasma and tissue collection. Loss of smOGT augmented SM contractile marker expression in aortic vessels of STZ-induced hyperglycemic smOGTKO mice. Consistently, smOGT deletion attenuated atherosclerotic lesion lipid burden (Oil red O), plaque area (H&E), leukocyte (CD45) and smooth muscle cell (ACTA2) abundance in Western diet-fed hyperglycemic smOGTKOApoE-/- mice. This was accompanied by increased SM contractile markers and reduced inflammatory and proliferative marker expression. Further, smOGT deletion attenuated YY1 and SRF expression (transcriptional regulators of SM contractile genes) in hyperglycemic smOGTKOApoE-/- and smOGTKO mice. These data uncover an athero-protective outcome of smOGT loss-of-function and suggest a direct regulatory role of OGT-mediated O-GlcNAcylation in VSMC de-differentiation in hyperglycemia.

Extracellular vesicle-mediated transfer of lncRNA CLDN10-AS1 aggravates low-density lipoprotein-induced vascular endothelial injury

Oxidized low-density lipoprotein (ox-LDL) stimulation impairs the oxidation-reduction equilibrium in vascular endothelial cells (VECs) and contributes to atherosclerosis (AS). This study probed the mechanisms of extracellular vesicle (EV)-mediated transfer of lncRNA CLDN10 antisense RNA 1 (CLDN10-AS1) in ox-LDL-induced VEC injury. Initially, VEC injury models were established by treating human umbilical vein endothelial cells (HUVECs) with ox-LDL. EVs were isolated from HUVECs (HUVECs-EVs) and identified. CLDN10-AS1, microRNA (miR)-186, and Yin Yang 1 (YY1) expressions in ox-LDL-treated HUVECs and EVs derived from these cells (ox-EVs) were measured. HUVECs were incubated with EVs, after which the cell viability, apoptosis, and concentrations of proinflammatory cytokines and oxidative stress markers were measured. We discovered that CLDN10-AS1 and YY1 were upregulated in ox-LDL-treated HUVECs, whereas miR-186 was downregulated. ox-EVs treatment elevated CLDN10-AS1 expression in HUVECs and ox-EVs overexpressing CLDN10-AS1 promoted VEC injury. Besides, CLDN10-AS1 is competitively bound to miR-186 and promoted YY1 expression. Rescue experiments revealed that miR-186 overexpression or YY1 suppression partially reversed the roles of ox-EVs overexpressing CLDN10-AS1 in ox-LDL-induced VEC injury. Lastly, clinical serum samples were collected for verification. Overall, CLDN10-AS1 carried by HUVECs-EVs into HUVECs competitively bound to miR-186 to elevate YY1 expression, thereby aggravating ox-LDL-induced VEC injury.

Transcriptional regulation of vascular smooth muscle cell proliferation, differentiation and senescence: Novel targets for therapy

Vascular smooth muscle cells (SMC) possess a unique cytoplasticity, regulated by transcriptional, translational and phenotypic transformation in response to a diverse range of extrinsic and intrinsic pathogenic factors. The mature, differentiated SMC phenotype is physiologically typified transcriptionally by expression of genes encoding "contractile" proteins, such as SMα-actin (ACTA2), SM-MHC (myosin-11) and SM22α (transgelin). When exposed to various pathological conditions (e.g., pro-atherogenic risk factors, hypertension), SMC undergo phenotypic modulation, a bioprocess enabling SMC to de-differentiate in immature stages or trans-differentiate into other cell phenotypes. As recent studies suggest, the process of SMC phenotypic transformation involves five distinct states characterized by different patterns of cell growth, differentiation, migration, matrix protein expression and declined contractility. These changes are mediated via the action of several transcriptional regulators, including myocardin and serum response factor. Conversely, other factors, including Kruppel-like factor 4 and nuclear factor-κB, can inhibit SMC differentiation and growth arrest, while factors such as yin yang-1, can promote SMC differentiation whilst inhibiting proliferation. This article reviews recent advances in our understanding of regulatory mechanisms governing SMC phenotypic modulation. We propose the concept that transcription factors mediating this switching are important biomarkers and potential pharmacological targets for therapeutic intervention in cardiovascular disease.

Pathogenic role of microRNAs in atherosclerotic ischemic stroke: Implications for diagnosis and therapy

Ischemic stroke resulting from atherosclerosis (particularly in the carotid artery) is one of the major subtypes of stroke and has a high incidence of death. Disordered lipid homeostasis, lipid deposition, local macrophage infiltration, smooth muscle cell proliferation, and plaque rupture are the main pathological processes of atherosclerotic ischemic stroke. Hepatocytes, macrophages, endothelial cells and vascular smooth muscle cells are the main cell types participating in these processes. By inhibiting the expression of the target genes in these cells, microRNAs play a key role in regulating lipid disorders and atherosclerotic ischemic stroke. In this article, we listed the microRNAs implicated in the pathology of atherosclerotic ischemic stroke and aimed to explain their pro- or antiatherosclerotic roles. Our article provides an update on the potential diagnostic use of miRNAs for detecting growing plaques and impending clinical events. Finally, we provide a perspective on the therapeutic use of local microRNA delivery and discuss the challenges for this potential therapy.

YY1 affects the levels and function of fibulin‑5 in ox‑LDL‑treated vascular smooth muscle cells

Fibulin-5 is reportedly involved in the pathological process of atherosclerosis (AS) where low expression has been frequently observed in ruptured atherosclerotic plaques. The aim of the present study was to determine the effects of fibulin-5 on the responses of vascular smooth muscle cells (VSMC) to oxidized low-density lipoprotein (ox-LDL). The expression of fibulin-5 was studied in human aortic-VSMCs (HA-VSMCs) treated with ox-LDL. Fibulin-5 was first overexpressed by the transfection of Ov-Fibulin-5 plasmids in HA-VSMCs challenged with ox-LDL to investigate its influence on cell proliferation, migration and invasion using Cell Counting Kit-8, wound healing and Transwell assays. Yin Yang-1 (YY1) was bioinformatically predicted to bind to the promoter sites of fibulin-5, which was subsequently confirmed by dual-luciferase reporter gene assay. Fibulin-5 overexpression was able to suppress cell proliferation, invasion and migration, which was effectively reversed by YY1 silencing by the transfection of siRNA-Fibulin-5 plasmids which could induced fibulin-5 silencing. YY1 binding sites in the promoter region of fibulin-5 were identified and confirmed in vitro by chromatin immunoprecipitation assay and dual-luciferase reporter gene assay. The present results suggested that as a modulator of fibulin-5, YY1 alleviated ox-LDL-induced proliferation, invasion, migration and phenotypic transition from differentiated contractile phenotype to dedifferentiated phenotype in VSMCs. However, the mechanism underlying the YY1-mediated regulation of fibulin-5 expression needs to be confirmed further in vivo. Nevertheless, targeting fibulin-5 and YY1 could be further developed for AS therapy.

The Anticancer Effect of a Conjugated Antimicrobial Peptide Against Colorectal Cancer (CRC) Cells

PURPOSE

Although antimicrobial peptides (AMPs) were initially known as compounds of the innate immune system to fight microbial pathogens, it has been recently proposed that differences in normal and cancer cell membranes cause the anticancer effect of these peptides. The aim of this study was to evaluate the anticancer effect of MELITININ+BMAP27-conjugated peptide against colorectal cancer (CRC) cells.

METHODS

The MELITININ+BMAP27-conjugated peptides were designed and the β-naphthylalanine residues were added to the termini to improve the anticancer effect. CRC cancer cell lines including HT29, SW742, HCT-116, and WiDr were used. After preparing concentrations of 5, 10, 25, 50, 100, 150, 200, and 400 μg/mL of peptide solution, the rate of cell death after 12, 24, and 48 h was assessed using MTT test. After confirmation of the 30 µg/mL efficacy and nontoxic concentration, the cells were exposed to this concentration, and the total RNA was extracted. The quantitative real-time PCR (RT-qPCR) technique was performed for the amplification of Bax, caspase3, atg5, and GAPDH (glyceraldehyde 3-phosphate dehydrogenase as the internal control) genes.

RESULTS

The cytotoxicity of peptide against normal cells exhibited that the IC50 at 24 and 4 h included 80 and 100 µg/mL, respectively. After 24-72 h of treatment, a significant difference in the mean percentage of CRC living cells was observed at concentrations of 50-400 μg/mL of conjugated peptide (p < 0.05). The IC50 of the peptide at 24, 48, and 72 h of exposure was measured as 30, 20, and 10 μg/mL, respectively. The peptide resulted in a significant increase of 2.35-fold in the mean expression of Bax gene in CRC cells (p < 0.001). It also caused a significant increase of 1.75 times (p = 0.0112) of caspase 3 gene and 1.2 times (p = 0.0217) of atg5 gene. There was no significant difference among cell lines regarding the expression of each gene.

CONCLUSION

The conjugated peptide caused the death of CRC lines via induction of the apoptosis and necrosis mechanisms. More studies are needed in this regard.

Phoenixin-14 regulates proliferation and apoptosis of vascular smooth muscle cells by modulation of KCNQ1OT1/miR-183-3p/CTNNB1 axis

Phoenixin-14 has been reported to be implicated in the process of blood glucose metabolism, reproduction, lipid deposition and cardioprotection. However, the role of phoenixin-14 in vascular smooth muscle cells (VSMCs) remains unkown. In this study, we focused on the effects of phoenixin-14 on VSMCs under oxidized low-density lipoprotein (ox-LDL) treatment. The experimental results demonstrated that phoenixin-14 inhibited mRNA level and nuclear translocation of β-catenin. Functionally, phoenixin-14 inhibited cell proliferation and facilitated apoptosis of VSMCs under ox-LDL stimulation, and CTNNB1 overexpression reversed these effects. Mechanistically, KCNQ1OT1 interacted with miR-183-3p to upregulate CTNNB1 in VSMCs. Furthermore, CTNNB1 expression was negatively correlated with miR-183-3p but positively associated with KCNQ1OT1. Rescue assays indicated that KCNQ1OT1 overexpression or Lithium chloride (LiCl) treatment reversed the effects of phoenixin-14 on proliferation and apoptosis of ox-LDL-stimulated VSMCs. In summary, phoenixin-14 regulates proliferation and apoptosis of ox-LDL-treated VSMCs by regulating the KCNQ1OT1/miR-183-3p/CTNNB1 axis.

The Characters of Graphene Oxide Nanoparticles and Doxorubicin Against HCT-116 Colorectal Cancer Cells In Vitro

PURPOSE

Colorectal cancer (CRC) is among the leading causes of cancer death worldwide. Graphene oxide (GO) plus doxorubicin (DOX) have low toxicity and facilitate drug carriage and provide enough surface. The GO-DOX anticancer effects against HCT-116 human CRC cells were compared with that of pure GO and DOX compounds.

METHODS

Different concentrations of graphene oxide (GO), doxorubicin (DOX), and graphene oxide plus doxorubicin (GO-DOX) were prepared. The MTT test was conducted to determine the viability of cells and flow cytometry was performed following DOX, GO, and GO-DOX exposure. Expressions of caspase 3, Bax, and ATG5 autophagy-related genes were investigated using RT-qPCR technique.

RESULTS

In the MTT test, DOX and GO at 100 µg/mL and 40 µg/mL exerted 50% cell death (LC50) against the HCT-116 cells. We observed significant differences in GO-DOX LC50 at concentrations of 1 (p = 0.003), 2.5 (p = 0.003), 5 (p = 0.00009), and 10 µg/mL (p = 0.0001). The rate of apoptosis following GO, DOX, and GO-DOX included 24%, 31%, and 56%, respectively. The GO-DOX significantly increased the ATG5 (3.1-fold, p < 0.0001), caspase 3 (4.7-fold, p < 0.0001), and Bax (4.3-fold, p < 0.0001) gene expression.

CONCLUSION

The GO-DOX exerted anticancer effects against the HCT-116 cells via inducing the apoptosis and autophagy.

CircSFMBT2 facilitates vascular smooth muscle cell proliferation by targeting miR-331-3p/HDAC5

OBJECTIVE

To investigate the functional role of circSFMBT2 in vascular smooth muscle cell (VSMC) proliferation and migration and the underlying molecular mechanism.

METHODS

The circSFMBT2 levels in neointimal tissue and platelet derived growth factor-BB (PDGF-BB)-treated VSMCs were detected by qRT-PCR. The role of circSFMBT2 in VSMC proliferation, migration and cell cycle distribution was assessed by MTT assay, transwell assay, wound healing assay and flow cytometry. The protein expression of contractile markers was evaluated by western blot. In vitro luciferase reporter assay, RNA pull-down assay, ChIP and coimmunoprecipitation (CoIP) were performed to explore the effects of circSFMBT2 on the downstream signaling pathway.

RESULTS

We found that circSFMBT2 was markedly increased in neointimal tissue relative to normal tissue and PDGF-BB-treated VSMCs relative to control VSMCs. The knockdown of circSFMBT2 by siRNA significantly inhibited the proliferation and migration of VSMCs. Interestingly, circSFMBT2 knockdown enhanced the expression of contractile marker proteins including SM22α, SM myosin heavy chain (SMMHC) and calponin. Further data demonstrated that circSFMBT2 interacted with miR-331-3p as a competing endogenous RNA and up-regulated the expression of histone deacetylase 5 (HDAC5), thereby regulating the level of angiogenic factor with G patch and FHA domains (Aggf1).

CONCLUSION

These results revealed that circSFMBT2 plays a vital role in VSMC proliferation and migration through the miR-331/HDAC5/Aggf1 axis, and suggest a novel target for treating proliferative vascular diseases.

The role of human cytomegalovirus in atherosclerosis: a systematic review

Atherosclerosis is a progressive vascular disease with increasing morbidity and mortality year by year in modern society. Human cytomegalovirus (HCMV) infection is closely associated with the development of atherosclerosis. HCMV infection may accelerate graft atherosclerosis and the development of transplant vasculopathy in organ transplantation. However, our current understanding of HCMV-associated atherosclerosis remains limited and is mainly based on clinical observations. The underlying mechanism of the involvement of HCMV infection in atherogenesis remains unclear. Here, we summarized current knowledge regarding the multiple influences of HCMV on a diverse range of infected cells, including vascular endothelial cells, vascular smooth muscle cells, monocytes, macrophages, and T cells. In addition, we described potential HCMV-induced molecular mechanisms, such as oxidative stress, endoplasmic reticulum stress, autophagy, lipid metabolism, and miRNA regulation, which are involved in the development of HCMV-associated atherogenesis. Gaining an improved understanding of these mechanisms will facilitate the development of novel and effective therapeutic strategies for the treatment of HCMV-related cardiovascular disease.

Genomic inbreeding trends, influential sire lines and selection in the global Thoroughbred horse population

The Thoroughbred horse is a highly valued domestic animal population under strong selection for athletic phenotypes. Here we present a high resolution genomics-based analysis of inbreeding in the population that may form the basis for evidence-based discussion amid concerns in the breeding industry over the increasing use of small numbers of popular sire lines, which may accelerate a loss of genetic diversity. In the most comprehensive globally representative sample of Thoroughbreds to-date (n = 10,118), including prominent stallions (n = 305) from the major bloodstock regions of the world, we show using pan-genomic SNP genotypes that there has been a highly significant decline in global genetic diversity during the last five decades (FIS R2 = 0.942, P = 2.19 × 10-13; FROH R2 = 0.88, P = 1.81 × 10-10) that has likely been influenced by the use of popular sire lines. Estimates of effective population size in the global and regional populations indicate that there is some level of regional variation that may be exploited to improve global genetic diversity. Inbreeding is often a consequence of selection, which in managed animal populations tends to be driven by preferences for cultural, aesthetic or economically advantageous phenotypes. Using a composite selection signals approach, we show that centuries of selection for favourable athletic traits among Thoroughbreds acts on genes with functions in behaviour, musculoskeletal conformation and metabolism. As well as classical selective sweeps at core loci, polygenic adaptation for functional modalities in cardiovascular signalling, organismal growth and development, cellular stress and injury, metabolic pathways and neurotransmitters and other nervous system signalling has shaped the Thoroughbred athletic phenotype. Our results demonstrate that genomics-based approaches to identify genetic outcrosses will add valuable objectivity to augment traditional methods of stallion selection and that genomics-based methods will be beneficial to actively monitor the population to address the marked inbreeding trend.

MicroRNA-147b suppresses the proliferation and invasion of non-small-cell lung cancer cells through downregulation of Wnt/β-catenin signalling via targeting of RPS15A

Deregulation of microRNAs (miRNAs) leads to malignant growth and aggressive invasion during cancer occurrence and progression. miR-147b has emerged as one of the cancer-related miRNAs that are dysregulated in multiple cancers. Yet, the relevance of miR-147b in non-small-cell lung cancer (NSCLC) remains unclear. In the present study, we aimed to report the biological function and signalling pathways mediated by miR-147b in NSCLC. Our results demonstrate that miR-147b expression is significantly downregulated in NSCLC tissues and cell lines. Overexpression of miR-147b decreased the proliferative ability, colony-forming capability, and invasive potential of NSCLC cells. Notably, our study identified ribosomal protein S15A (RPS15A), an oncogene in NSCLC, as a target gene of miR-147b. Our results showed that miR-147b negatively modulates RPS15A expression in NSCLC cells. An inverse correlation between miR-147b and RPS15A was evidenced in NSCLC specimens. Moreover, miR-147b overexpression downregulated the activation of Wnt/β-catenin signalling via targeting of RPS15A. Overexpression of RPS15A partially reversed the miR-147b-mediated antitumour effect in NSCLC cells. Collectively, these findings reveal that miR-147b restricts the proliferation and invasion of NSCLC cells by inhibiting RPS15A-induced Wnt/β-catenin signalling and suggest that the miR-147b/RPS15A/Wnt/β-catenin axis is an important regulatory mechanism for malignant progression of NSCLC.

The role of microRNAs in the involvement of vascular smooth muscle cells in the development of atherosclerosis

MicroRNAs (miRNAs) are a class of nonprotein-encoding RNAs of ~22 nucleotides in length that bind to or complement each other with a target gene messenger RNA (mRNA) to promote mRNA degradation or inhibit translation of the target mRNA. The protein required [such as Toll-like receptor (TLR) proteins] is controlled at an optimal level. By affecting protein translation, miRNAs have become powerful regulators of biological processes, including development, differentiation, cell proliferation, and apoptosis. MiRNAs are involved in the regulation of proliferation, migration, and apoptosis of vascular smooth muscle cells (VSMCs), thereby affecting the formation of atherosclerosis (AS). In recent years, the role and mechanism of miRNAs involved in AS development in VSMCs have been studied extensively. In the current study, the results and progress in miRNA research are reviewed.

YY1 regulates cancer cell immune resistance by modulating PD-L1 expression

Recent advances in the treatment of various cancers have resulted in the adaptation of several novel immunotherapeutic strategies. Notably, the recent intervention through immune checkpoint inhibitors has resulted in significant clinical responses and prolongation of survival in patients with several therapy-resistant cancers (melanoma, lung, bladder, etc.). This intervention was mediated by various antibodies directed against inhibitory receptors expressed on cytotoxic T-cells or against corresponding ligands expressed on tumor cells and other cells in the tumor microenvironment (TME). However, the clinical responses were only observed in a subset of the treated patients; it was not clear why the remaining patients did not respond to checkpoint inhibitor therapies. One hypothesis stated that the levels of PD-L1 expression correlated with poor clinical responses to cell-mediated anti-tumor immunotherapy. Hence, exploring the underlying mechanisms that regulate PD-L1 expression on tumor cells is one approach to target such mechanisms to reduce PD-L1 expression and, therefore, sensitize the resistant tumor cells to respond to PD-1/PD-L1 antibody treatments. Various investigations revealed that the overexpression of the transcription factor Yin Yang 1 (YY1) in most cancers is involved in the regulation of tumor cells' resistance to cell-mediated immunotherapies. We, therefore, hypothesized that the role of YY1 in cancer immune resistance may be correlated with PD-L1 overexpression on cancer cells. This hypothesis was investigated and analysis of the reported literature revealed that several signaling crosstalk pathways exist between the regulations of both YY1 and PD-L1 expressions. Such pathways include p53, miR34a, STAT3, NF-kB, PI3K/AKT/mTOR, c-Myc, and COX-2. Noteworthy, many clinical and pre-clinical drugs have been utilized to target these above pathways in various cancers independent of their roles in the regulation of PD-L1 expression. Therefore, the direct inhibition of YY1 and/or the use of the above targeted drugs in combination with checkpoint inhibitors should result in enhancing the cell-mediated anti-tumor cell response and also reverse the resistance observed with the use of checkpoint inhibitors alone.

Targeting epigenetics and non-coding RNAs in atherosclerosis: from mechanisms to therapeutics

Atherosclerosis, the principal cause of cardiovascular death worldwide, is a pathological disease characterized by fibro-proliferation, chronic inflammation, lipid accumulation, and immune disorder in the vessel wall. As the atheromatous plaques develop into advanced stage, the vulnerable plaques are prone to rupture, which causes acute cardiovascular events, including ischemic stroke and myocardial infarction. Emerging evidence has suggested that atherosclerosis is also an epigenetic disease with the interplay of multiple epigenetic mechanisms. The epigenetic basis of atherosclerosis has transformed our knowledge of epigenetics from an important biological phenomenon to a burgeoning field in cardiovascular research. Here, we provide a systematic and up-to-date overview of the current knowledge of three distinct but interrelated epigenetic processes (including DNA methylation, histone methylation/acetylation, and non-coding RNAs), in atherosclerotic plaque development and instability. Mechanistic and conceptual advances in understanding the biological roles of various epigenetic modifiers in regulating gene expression and functions of endothelial cells (vascular homeostasis, leukocyte adhesion, endothelial-mesenchymal transition, angiogenesis, and mechanotransduction), smooth muscle cells (proliferation, migration, inflammation, hypertrophy, and phenotypic switch), and macrophages (differentiation, inflammation, foam cell formation, and polarization) are discussed. The inherently dynamic nature and reversibility of epigenetic regulation, enables the possibility of epigenetic therapy by targeting epigenetic "writers", "readers", and "erasers". Several Food Drug Administration-approved small-molecule epigenetic drugs show promise in pre-clinical studies for the treatment of atherosclerosis. Finally, we discuss potential therapeutic implications and challenges for future research involving cardiovascular epigenetics, with an aim to provide a translational perspective for identifying novel biomarkers of atherosclerosis, and transforming precision cardiovascular research and disease therapy in modern era of epigenetics.