Search

Carotid body tumor (CBT) is a rare neck tumor located at the adventitia of the common carotid artery bifurcation. The prominent pathological features of CBT are high vascularization and abnormal proliferation. However, single‐cell transcriptome analysis of the microenvironment composition and molecular complexity in CBT has yet to be performed. In this study, we performed single‐cell RNA sequencing (scRNA‐seq) analysis on human CBT to define the cells that contribute to hypervascularization and chronic hyperplasia. Unbiased clustering analysis of transcriptional profiles identified 16 distinct cell populations including endothelial cells (ECs), smooth muscle cells (SMCs), neuron cells, macrophage cells, neutrophil cells, and T cells. Within the ECs population, we defined subsets with angiogenic capacity plus clear signs of later endothelial progenitor cells (EPCs) to normal ECs. Two populations of macrophages were detectable in CBT, macrophage1 showed enrichment in hypoxia‐inducible factor‐1 (HIF‐1) and as well as an early EPCs cell‐like population expressing CD14 and vascular endothelial growth factor. In addition to HIF‐1‐related transcriptional protein expression, macrophages1 also display a neovasculogenesis‐promoting phenotype. SMCs included three populations showing platelet‐derived growth factor receptor beta and vimentin expression, indicative of a cancer‐associated fibroblast phenotype. Finally, we identified three types of neuronal cells, including chief cells and sustentacular cells, and elucidated their distinct roles in the pathogenesis of CBT and abnormal proliferation of tumors. Overall, our study provided the first comprehensive characterization of the transcriptional landscape of CBT at scRNA‐seq profiles, providing novel insights into the mechanisms underlying its formation. [ABSTRACT FROM AUTHOR]

Objectives Oral squamous cell carcinoma (OSCC) is a common malignancy in the oral and maxillofacial regions with an increasing incidence rate. Circular RNA (circRNA) is a recently discovered long-chain non-coding RNA family member. The objective of this study was to analyze the role of circ_0068162 in OSCC development. Methods We downloaded sample data GSE145608 from the Gene Expression Omnibus database. Online databases Starbase, TargetScan and miRDB were used to predict the target microRNAs (miRNAs) and genes. Cell viability and proliferation were assessed using the CCK-8 and EdU assays, respectively. Cell migration and invasion abilities were detected using transwell assay. The double luciferase reporter and RNA immunoprecipitation (RIP) assays were performed to verify the interaction relationship between the identified target molecules. RNase R and actinomycin D treatment were performed to analyze the stability of circ_0068162. Results We found that circ_0068162 was overexpressed in the cytoplasm of OSCC cells and clinical OSCC tissues. Knockdown of circ_0068162 inhibited the growth, migration and invasion of OSCC cells. We also identified miR-186 as the target miRNA of circ_0068162, and JAG1 and JAG2 as the target genes of miR-186. The miR-186 inhibitor rescued the effects of sh-circ_0068162 and JAG1/JAG2 overexpression rescued the effects of miR-186 mimic in OSCC cells. Furthermore, ESRP1 promoted the biosynthesis of circ_0068162. Conclusions The circ_0068162/miR-186/JAGs/ESRP1 feedback loop is closely related to OSCC development. [ABSTRACT FROM AUTHOR]

Cytosolic RNA/DNA sensing elicits primary defense against viral pathogens. Interferon regulatory factor 3 (IRF3), a key signal mediator/transcriptional factor of the antiviral-sensing pathway, is indispensible for interferon production and antiviral defense. However, how the status of IRF3 activation is controlled remains elusive. Through a functional screen of the human kinome, we found that mammalian sterile 20-like kinase 1 (Mst1), but not Mst2, profoundly inhibited cytosolic nucleic acid sensing. Mst1 associated with IRF3 and directly phosphorylated IRF3 at Thr75 and Thr253. This Mst1-mediated phosphorylation abolished activated IRF3 homodimerization, its occupancy on chromatin, and subsequent IRF3-mediated transcriptional responses. In addition, Mst1 also impeded virus-induced activation of TANK-binding kinase 1 (TBK1), further attenuating IRF3 activation. As a result, Mst1 depletion or ablation enabled an enhanced antiviral response and defense in cells and mice. Therefore, the identification of Mst1 as a novel physiological negative regulator of IRF3 activation provides mechanistic insights into innate antiviral defense and potential antiviral prevention strategies.

The p.Thr61Ile (p.T61I) mutation in coiled‐coil‐helix–coiled‐coil‐helix domain containing 2 (CHCHD2) was deemed a causative factor in Parkinson's disease (PD). However, the pathomechanism of the CHCHD2 p.T61I mutation in PD remains unclear. Few existing mouse models of CHCHD2‐related PD completely reproduce the features of PD, and no transgenic or knock‐in (KI) mouse models of CHCHD2 mutations have been reported. In the present study, we generated a novel CHCHD2 p.T61I KI mouse model, which exhibited accelerated mortality, progressive motor deficits, and dopaminergic (DA) neurons loss with age, accompanied by the accumulation and aggregation of α‐synuclein and p‐α‐synuclein in the brains of the mutant mice. The mitochondria of mouse brains and induced pluripotent stem cells (iPSCs)‐derived DA neurons carrying the CHCHD2 p.T61I mutation exhibited aberrant morphology and impaired function. Mechanistically, proteomic and RNA sequencing analysis revealed that p.T61I mutation induced mitochondrial dysfunction in aged mice likely through repressed insulin‐degrading enzyme (IDE) expression, resulting in the degeneration of the nervous system. Overall, this CHCHD2 p.T61I KI mouse model recapitulated the crucial clinical and neuropathological aspects of patients with PD and provided a novel tool for understanding the pathogenic mechanism and therapeutic interventions of CHCHD2‐related PD. [ABSTRACT FROM AUTHOR]

Background: Arterial stiffness index (ASI) is a potential risk factor for cerebrovascular and cardiometabolic diseases, but the causal links between them are inconclusive. The aim is to evaluate the causal effects of ASI on cerebrovascular and cardiometabolic diseases by Mendelian randomization (MR). Methods: Two-sample MR analysis was performed to infer causal links. Genetic variants significantly associated with ASI were extracted. The inverse variance weighted method was used for estimating the effects. Sensitivity analysis was performed to test heterogeneity or pleiotropy. Results: MR analysis indicated an effect of genetically predicted ASI on the risk of ischemic stroke (IS) of all causes (OR = 1.894, 95% CI 1.210–2.965, p = 0.005). No links were identified between genetically predicted ASI and other cerebrovascular or cardiometabolic diseases (all p > 0.05). Subgroup analysis of IS etiologies found a suggestive association between genetically predicted ASI and large artery atherosclerosis stroke (LAS) (OR = 3.726, 95% CI 1.230–11.286, p = 0.020). There were no effects of ASI on IS due to cardioembolism or small vessel occlusion. Conclusion: The current MR analysis suggested that genetically predicted ASI was associated with higher risk of IS of all causes. The results and the underlying pathways or mechanisms between ASI and IS needs further investigation. [ABSTRACT FROM AUTHOR]