Genome-wide association analysis of hypertension and epigenetic aging reveals shared genetic architecture and identifies novel risk loci.

Hypertension is a disease associated with epigenetic aging. However, the pathogenic mechanism underlying this relationship remains unclear. We aimed to characterize the shared genetic architecture of hypertension and epigenetic aging, and identify novel risk loci. Leveraging genome-wide association studies (GWAS) summary statistics of hypertension (129,909 cases and 354,689 controls) and four epigenetic clocks (N = 34,710), we investigated genetic architectures and genetic overlap using bivariate casual mixture model and conditional/conjunctional false discovery rate methods. Functional gene-sets pathway analyses were performed by functional mapping and gene annotation (FUMA) protocol. Hypertension was polygenic with 2.8 K trait-influencing genetic variants. We observed cross-trait genetic enrichment and genetic overlap between hypertension and all four measures of epigenetic aging. Further, we identified 32 distinct genomic loci jointly associated with hypertension and epigenetic aging. Notably, rs1849209 was shared between hypertension and three epigenetic clocks (HannumAge, IEAA, and PhenoAge). The shared loci exhibited a combination of concordant and discordant allelic effects. Functional gene-set analyses revealed significant enrichment in biological pathways related to sensory perception of smell and nervous system processes. We observed genetic overlaps with mixed effect directions between hypertension and all four epigenetic aging measures, and identified 32 shared distinct loci with mixed effect directions, 25 of which were novel for hypertension. Shared genes enriched in biological pathways related to olfaction.

Acetylcytidine modification of Amotl1 by N-acetyltransferase 10 contributes to cardiac fibrotic expansion in mice after myocardial infarction.

Cardiac fibrosis is a pathological scarring process that impairs cardiac function. N-acetyltransferase 10 (Nat10) is recently identified as the key enzyme for the N4-acetylcytidine (ac4C) modification of mRNAs. In this study, we investigated the role of Nat10 in cardiac fibrosis following myocardial infarction (MI) and the related mechanisms. MI was induced in mice by ligation of the left anterior descending coronary artery; cardiac function was assessed with echocardiography. We showed that both the mRNA and protein expression levels of Nat10 were significantly increased in the infarct zone and border zone 4 weeks post-MI, and the expression of Nat10 in cardiac fibroblasts was significantly higher compared with that in cardiomyocytes after MI. Fibroblast-specific overexpression of Nat10 promoted collagen deposition and induced cardiac systolic dysfunction post-MI in mice. Conversely, fibroblast-specific knockout of Nat10 markedly relieved cardiac function impairment and extracellular matrix remodeling following MI. We then conducted ac4C-RNA binding protein immunoprecipitation-sequencing (RIP-seq) in cardiac fibroblasts transfected with Nat10 siRNA, and revealed that angiomotin-like 1 (Amotl1), an upstream regulator of the Hippo signaling pathway, was the target gene of Nat10. We demonstrated that Nat10-mediated ac4C modification of Amotl1 increased its mRNA stability and translation in neonatal cardiac fibroblasts, thereby increasing the interaction of Amotl1 with yes-associated protein 1 (Yap) and facilitating Yap translocation into the nucleus. Intriguingly, silencing of Amotl1 or Yap, as well as treatment with verteporfin, a selective and potent Yap inhibitor, attenuated the Nat10 overexpression-induced proliferation of cardiac fibroblasts and prevented their differentiation into myofibroblasts in vitro. In conclusion, this study highlights Nat10 as a crucial regulator of myocardial fibrosis following MI injury through ac4C modification of upstream activators within the Hippo/Yap signaling pathway.

lncRNA Gm20257 alleviates pathological cardiac hypertrophy by modulating the PGC-1α-mitochondrial complex IV axis.

Pathological cardiac hypertrophy, a major contributor to heart failure, is closely linked to mitochondrial function. The roles of long noncoding RNAs (lncRNAs), which regulate mitochondrial function, remain largely unexplored in this context. Herein, a previously unknown lncRNA, Gm20257, was identified. It markedly increased under hypertrophic stress in vivo and in vitro. The suppression of Gm20257 by using small interfering RNAs significantly induced cardiomyocyte hypertrophy. Conversely, the overexpression of Gm20257 through plasmid transfection or adeno-associated viral vector-9 mitigated angiotensin II-induced hypertrophic phenotypes in neonatal mouse ventricular cells or alleviated cardiac hypertrophy in a mouse TAC model respectively, thus restoring cardiac function. Importantly, Gm20257 restored mitochondrial complex IV level and enhanced mitochondrial function. Bioinformatics prediction showed that Gm20257 had a high binding score with peroxisome proliferator-activated receptor coactivator-1 (PGC-1α), which could increase mitochondrial complex IV. Subsequently, Western blot analysis results revealed that Gm20257 substantially affected the expression of PGC-1α. Further analyses through RNA immunoprecipitation and immunoblotting following RNA pull-down indicated that PGC-1α was a direct downstream target of Gm20257. This interaction was demonstrated to rescue the reduction of mitochondrial complex IV induced by hypertrophic stress and promote the generation of mitochondrial ATP. These findings suggest that Gm20257 improves mitochondrial function through the PGC-1α-mitochondrial complex IV axis, offering a novel approach for attenuating pathological cardiac hypertrophy.

ITFG2, an immune-modulatory protein, targets ATP 5b to maintain mitochondrial function in myocardial infarction.

ITFG2, as an immune-modulatory intracellular protein that modulate the fate of B cells and negatively regulates mTORC1 signaling. ITFG2 is highly expressed in the heart, but its pathophysiological function in heart disease is unclear. In this study, we found that in MI mice, overexpression of ITFG2 via an AAV9 vector significantly reduced the infarct size and ameliorated cardiac function. Knockdown of endogenous ITFG2 by shRNA partially aggravated ischemia-induced cardiac dysfunction. In cardiac-specific ITFG2 transgenic (TG) mice, myocardial infarction size was smaller, eject fraction (EF) and fractional shortening (FS) was higher compared to those in wild-type (WT) mice, suggesting ITFG2 reversed cardiac dysfunction induced by MI. In hypoxic neonatal cardiomyocytes (NMCMs), overexpression of ITFG2 maintained mitochondrial function by increasing intracellular ATP production, reducing ROS levels, and preserving the mitochondrial membrane potential (MMP). Overexpression of ITFG2 reversed the mitochondrial respiratory dysfunction in NMCMs induced by hypoxia. Knockdown of endogenous ITFG2 by siRNA did the opposite. Mechanism, ITFG2 formed a complex with NEDD4-2 and ATP 5b and inhibited the binding of NEDD4-2 with ATP 5b leading to the reduction ubiquitination of ATP 5b. Our findings reveal a previously unknown ability of ITFG2 to protect the heart against ischemic injury by interacting with ATP 5b and thereby regulating mitochondrial function. ITFG2 has promise as a novel strategy for the clinical management of MI.

YAP1 inhibits the senescence of alveolar epithelial cells by targeting Prdx3 to alleviate pulmonary fibrosis.

The senescence of alveolar type II (AT2) cells impedes self-repair of the lung epithelium and contributes to lung injury in the setting of idiopathic pulmonary fibrosis (IPF). Yes-associated protein 1 (YAP1) is essential for cell growth and organ development; however, the role of YAP1 in AT2 cells during pulmonary fibrosis is still unclear. YAP1 expression was found to be downregulated in the AT2 cells of PF patients. Deletion of YAP1 in AT2 cells resulted in lung injury, exacerbated extracellular matrix (ECM) deposition, and worsened lung function. In contrast, overexpression of YAP1 in AT2 cells promoted alveolar regeneration, mitigated pulmonary fibrosis, and improved lung function. In addition, overexpression of YAP1 alleviated bleomycin (BLM) -induced senescence of alveolar epithelial cells both in vivo and in vitro. Moreover, YAP1 promoted the expression of peroxiredoxin 3 (Prdx3) by directly interacting with TEAD1. Forced expression of Prdx3 inhibited senescence and improved mitochondrial dysfunction in BLM-treated MLE-12 cells, whereas depletion of Prdx3 partially abrogated the protective effect of YAP1. Furthermore, overexpression of Prdx3 facilitated self-repair of the injured lung and reduced ECM deposition, while silencing Prdx3 attenuated the antifibrotic effect of YAP1. In conclusion, this study demonstrated that YAP1 alleviates lung injury and pulmonary fibrosis by regulating Prdx3 expression to improve mitochondrial dysfunction and block senescence in AT2 cells, revealing a potential novel therapeutic strategy for pulmonary fibrosis.

Unraveling Immune Heterogeneity across Pan-Cancer and Deep Insights in Lung Adenocarcinoma based on Alternative Splicing.

Alternative splicing (AS) participates in tumor development and tumor microenvironment formation. However, the landscape of immune infiltrating AS events (IIASE) in pan-cancer and mechanisms of AS in lung adenocarcinoma (LUAD) have not been comprehensively characterized. We systematically profiled the IIASE landscape of pan-cancer using data from The Cancer Genome Atlas (TCGA), analyzing both commonalities and specific characteristics among different cancer types. We found that AS events tend to occur specifically in one cancer type rather than in multiple cancer types. AS events were used to classify 512 LUAD samples into two subtypes by unsupervised clustering: aberrant splicing subtype (ABS) and immune infiltrating subtype (IIS). The two subtypes showed significant differences in clinicopathology, prognosis, transcriptomics, genomics and immune microenvironment. We constructed a classification signature comprising 10 genes involved in 14 AS events using Logistic regression. The robustness of the signature was validated in three independent datasets using survival analysis. To explore AS mechanisms in LUAD, we constructed subtype-specific co-expression networks using Pearson correlation analysis. AS event of AKT3 regulated by splicing factor ENOX1 was associated with poor prognosis in LUAD. Overall, we outline AS events associated with immune infiltration in pan-cancer and this study provides insights into AS mechanisms in LUAD patient classification.

Ramelteon alleviates myocardial ischemia/reperfusion injury (MIRI) through Sirt3--dependent regulation of cardiomyocyte apoptosis.

Reperfusion stands as a pivotal intervention for ischemic heart disease. However, the restoration of blood flow to ischemic tissue always lead to further damage, which is known as myocardial ischemia/reperfusion injury (MIRI). Ramelteon is an orally administered drug used to improve sleep quality, which is famous for its high bioadaptability and absence of notable addictive characteristics. However, the specific mechanism by which it improves MIRI is still unclear. Sirtuin-3 (Sirt3), primarily located in mitochondria, is crucial in mitigating many cardiac diseases, including MIRI. Based on the structure of Sirt3, we simulated molecular docking and identified several potential amino acid binding sites between it and ramelteon. Therefore, we propose a hypothesis that ramelteon may exert cardioprotective effects by activating the Sirt3 signaling pathway. Our results showed that the activation levels and expression level of Sirt3 were significantly decreased in MIRI tissue and H2O2 stimulated H9C2 cells, while ramelteon treatment upregulated Sirt3 activity and expression. After treat with 3-TYP, a classic Sirt3 activity inhibitor, we constructed myocardial ischemia/reperfusion surgery in vivo and induced H9C2 cells with H2O2 in vitro. The results showed that the myocardial protection and anti-apoptotic effects of ramelteon were antagonized by 3-TYP, indicating that the activation of Sirt3 is a key mechanism for ramelteon to exert myocardial protection. In summary, our results confirm a novel mechanism by which ramelteon improves MIRI by activating Sirt3 signaling pathway, providing strong evidence for the treatment of MIRI with ramelteon.

Berberine inhibits NLRP3 inflammasome activation by regulating mTOR/mtROS axis to alleviate diabetic cardiomyopathy.

Diabetes cardiomyopathy (DCM) refers to myocardial dysfunction and disorganization resulting from diabetes. In this study, we investigated the effects of berberine on cardiac function in male db/db mice with metformin as a positive control. After treatment for 8 weeks, significant improvements in cardiac function and a reduction in collagen deposition were observed in db/db mice. Furthermore, inflammation and pyroptosis were seen to decrease in these mice, as evidenced by decreased expressions of p-mTOR, NOD-like receptor thermal protein domain associated protein 3 (NLRP3), IL-1ß, IL-18, caspase-1, and gasdermin D (GSDMD). In vitro experiments on H9C2 cells showed that glucose exposure at 33 mmol/L induced pyroptosis, whereas berberine treatment reduced the expression of p-mTOR and NLRP3 inflammasome components. Moreover, berberine treatment was seen to inhibit the generation of mitochondrial reactive oxygen species (mtROS) and effectively improve cell damage in high glucose-induced H9C2 cells. The mTOR inhibitor, Torin-1, showed a therapeutic effect similar to that of berberine, by reducing the expression of NLRP3 inflammasome components and inhibiting mtROS generation. However, the activation of mTOR by MHY1485 partially nullified berberine's protective effects during high glucose stress. Collectively, our study reveals the mechanism that berberine regulates the mTOR/mtROS axis to inhibit pyroptosis induced by NLRP3 inflammasome activation, thereby alleviating DCM.

Gasdermin D-Mediated Pyroptosis in Diabetic Cardiomyopathy: Molecular Mechanisms and Pharmacological Implications.

Diabetic cardiomyopathy (DCM) is a pathophysiological condition triggered by diabetes mellitus (DM), which can lead to heart failure (HF). One of the most important cellular processes associated with DCM is the death of cardiomyocytes. Gasdermin D (GSDMD) plays a key role in mediating pyroptosis, a type of programmed cell death closely associated with inflammasome activation. Recent studies have revealed that pyroptosis is induced during hyperglycemia, which is crucial to the development of DCM. Although the effects of pyroptosis on DCM have been discussed, the relationship between DCM and GSDMD is not fully clarified. Recent studies gave us the impetus for clarifying the meaning of GSDMD in DCM. The purpose of this review is to summarize new and emerging insights, mainly discussing the structures of GSDMD and the mechanism of pore formation, activation pathways, molecular mechanisms of GSDMD-mediated pyroptosis, and the therapeutic potential of GSDMD in DCM. The implications of this review will pave the way for a new therapeutic target in DCM.

Up-regulated SPP1 increases the risk from IPF to lung cancer via activating the pro-tumor macrophages.

The incidence of lung cancer (LC) in Idiopathic Pulmonary Fibrosis (IPF) patients is more than twice that in non-IPF. This study aims to investigate IPF-to-LC pathogenesis and to develop a predictor for detecting IPF predisposing patients to LC. We conducted unsupervised clustering to detect high-risk subtypes from IPF to LC. Subsequently, we performed single-cell RNA-seq analysis to characterize high-risk IPF by examining the immune microenvironment. We identified 42 common immune function-related pathogenic genes between IPF and LC. We developed an LC risk classifier for IPF patients, comprising five genes: SPP1, MMP9, MMP12, FABP4, and IL1B. The five-gene classifier can successfully distinguish the high-risk population from IPF patients. High-risk IPF patients exhibited an immunosuppressive microenvironment with higher oncogene expression than low-risk patients. Single-cell analysis revealed that SPP1+ macrophages at the terminal of macrophages' developmental trajectory may promote the progression from IPF to LC. The strong crosstalk between SPP1+ macrophages and inflammation-related cancer-associated fibroblasts promoted the tumorigenic process in IPF. In vitro, assays showed that co-culturing macrophages overexpressing SPP1 with MRC-5 cells induced the transition of fibroblasts into cancer-associated fibroblasts. SPP1 produced by macrophages promoted epithelial-mesenchymal transition in alveolar epithelial cells via stimulating the upregulation of N-cadherin and Vimentin in MLE-12 cells. This study provided a novel method to identify the LC risk population from IPF, revealing the cellular interactions involved in the transition from IPF to LC. Our findings highlighted SPP1 as a critical driver in IPF progression, offering a potential target for therapy in fibrosis.

Mutant RB1 enhances therapeutic efficacy of PARPis in lung adenocarcinoma by triggering the cGAS/STING pathway.

Poly (ADP-ribose) polymerase inhibitors (PARPis) are approved for cancer therapy according to their synthetic lethal interactions, and clinical trials have been applied in non-small cell lung cancer. However, the therapeutic efficacy of PARPis in lung adenocarcinoma (LUAD) is still unknown. We explored the effect of a mutated retinoblastoma gene (RB1) on PARPi sensitivity in LUAD. Bioinformatic screening was performed to identify PARPi-sensitive biomarkers. Here, we showed that viability of LUAD cell lines with mutated RB1 was significantly decreased by PARPis (niraparib, rucaparib, and olaparib). RB1 deficiency induced genomic instability, prompted cytosolic double-stranded DNA (dsDNA) formation, activated the cGAS/STING pathway, and upregulated downstream chemokines CCL5 and CXCL10, triggering immune cell infiltration. Xenograft experiments indicated that PARPi treatment reduced tumorigenesis in RB1-KO mice. Additionally, single-cell RNA sequencing analysis showed that malignant cells with downregulated expression of RB1 had more communications with other cell types, exhibiting activation of specific signaling such as GAS, IFN response, and antigen-presenting and cytokine activities. Our findings suggest that RB1 mutation mediates the sensitivity to PARPis through a synthetic lethal effect by triggering the cGAS/STING pathway and upregulation of immune infiltration in LUAD, which may be a potential therapeutic strategy.

Preventive effects of Ramelteon on bleomycin-induced pulmonary fibrosis in mice.

Pulmonary fibrosis (PF) is a devastating lung disease that leads to impaired lung function and ultimately death. Several studies have suggested that melatonin, a hormone involved in regulating sleep-wake cycles, may be effective in improving PF. Ramelteon, an FDA-approved melatonin receptor agonist, has shown promise in exerting an anti-PF effect similar to melatonin. However, further investigations are required for illuminating the extent on its therapeutic benefits and the underlying molecular mechanisms. In this work, a mouse lung fibrosis model was built through intratracheal administration of bleomycin (BLM). Subsequently, the mice were administrated Ramelteon for a duration of 3 weeks to explore its efficacy and mechanism of action. Additionally, we utilized a TGF-ß1-induced MRC-5 cell model to further investigate the molecular mechanism underlying ramelteon's effects. Functionally, Ramelteon partially abrogated TGF-ß1-induced pulmonary fibrosis and reduced fibroblast proliferation, extracellular matrix deposition, and differentiation into myofibroblasts. In vivo experiments, ramelteon attenuated BLM-induced pulmonary fibrosis and collagen deposition. Mechanistically, ramelteon exerts its beneficial effect by alleviating translocation and expression of YAP1, a core component of Hippo pathway, from cytoplasm to nucleus; however, overexpression of YAP1 reversed this effect. In conclusion, our findings indicate that ramelteon can improve PF by regulating Hippo pathway and may become a potential candidate as a therapy to PF.

Multi-omics integration analysis unveils heterogeneity in breast cancer at the individual level.

Identifying robust breast cancer subtypes will help to reveal the cancer heterogeneity. However, previous breast cancer subtypes were based on population-level quantitative gene expression, which is affected by batch effects and cannot be applied to individuals. We detected differential gene expression, genomic, and epigenomic alterations to identify driver differential expression at the individual level. The individual driver differential expression reflected the breast cancer patients' heterogeneity and revealed four subtypes. Mesenchymal subtype as the most aggressive subtype harbored deletion and downregulated expression of genes in chromosome 11q23 region. Specifically, silencing of the SDHD gene in 11q23 promoted the invasion and migration of breast cancer cells in vitro by the epithelial-mesenchymal transition. The immunologically hot subtype displayed an immune-hot microenvironment, including high T-cell infiltration and upregulated PD-1 and CTLA4. Luminal and genomic-unstable subtypes showed opposite macrophage polarization, which may be regulated by the ligand-receptor pairs of CD99. The integration of multi-omics data at the individual level provides a powerful framework for elucidating the heterogeneity of breast cancer.

Neuroepithelial cell-transforming 1 promotes cardiac fibrosis via the Wnt/ß-catenin signaling pathway.

This study found that the level of neuroepithelial cell-transforming gene 1 protein (NET1) was significantly increased in a mouse cardiac fibrosis model. Moreover, the expression level of NET1 was increased in cardiac fibrosis induced by TGF-ß1, suggesting that NET1 was involved in the pathological process of cardiac fibrosis. Overexpression of NET1 promoted ß-catenin expression in the nucleus and significantly increased the proliferation and migration of cardiac fibroblasts. NET1 may form a complex with ß-catenin through GSK3ß. Knockdown of ß-catenin alleviated the effects of NET1 overexpression on collagen production and cell migration. In the heart of NET1 knockout mice, NET1 knockout can reduce the expression of ß-catenin, α-SMA, and collagen content induced by MI. In conclusion, NET1 may regulate the activation of Wnt/ß-catenin and TGF/Smads signaling pathway, promote collagen synthesis in fibroblasts, and participate in cardiac fibrosis. Thus, NET1 may be a potential therapeutic target in cardiac fibrosis.

Nucleosome assembly protein 1 like 1 (NAP1L1) promotes cardiac fibrosis by inhibiting YAP1 ubiquitination and degradation.

Myocardial fibrosis post myocardial infarction (MI) is characterized by abnormal extracellular matrix (ECM) deposition and cardiac dysfunction could finally develop into serious heart disease, like heart failure. Lots of regulating factors involved in this pathological process have been reported while the specific mediators and underlying mechanisms remain to need to be further investigated. As part of the NAP1 family, Nucleosome assembly protein 1 like 1 (NAP1L1) is expressed in a wide variety of tissues. Here, we report that NAP1L1 is a significant regulator of cardiac fibrosis and is upregulated in ischemic cardiomyopathy patient hearts. Enhanced expression of NAP1L1 can promote cardiac fibroblasts (CFs) proliferation, migration, and differentiation into myofibroblasts. In contrast, loss of NAP1L1 decreased fibrosis-related mRNA and protein levels, inhibited the trans-differentiation, and blunted migration and proliferation of CFs after Transforming Growth Factorß1（TGF-ß1）stimulation. In vivo, NAP1L1 knockout mice enhanced cardiac function and reduced fibrosis area in response to MI stimuli. Mechanically, NAP1L1 binding to Yes-associated protein 1 (YAP1) protein influences its stability, and silencing NAP1L1 can inhibit YAP1 expression by promoting its ubiquitination and degradation in CFs. Collectively, NAP1L1 could potentially be a new therapeutic target for various cardiac disorders, including myocardial fibrosis.

Long non-coding RNA PFI inhibits apoptosis of alveolar epithelial cells to alleviate lung injury via miR-328-3p/Creb1 axis.

Acute lung injury (ALI), a common clinical type of critical illness, is an acute hypoxic respiratory insufficiency caused by the damage of alveolar epithelial cells and capillary endothelial cells. In a previous study, we reported a novel lncRNA, lncRNA PFI, which could protect against pulmonary fibrosis in pulmonary fibroblasts. The present study demonstrated that lncRNA PFI was downregulated in alveolar epithelial cell of mice injury lung tissues, and further investigated the role of lncRNA PFI in regulating inflammation-induced alveolar epithelial cell apoptosis. Overexpression of lncRNA PFI could partially abrogated bleomycin induced type II AECs injured. Subsequently, bioinformatic prediction revealed that lncRNA PFI might directly bind to miR-328-3p, and further AGO-2 RNA binding protein immunoprecipitation (RIP) assay confirmed their binding relationship. Furthermore, miR-328-3p promoted apoptosis in MLE-12 cells by limiting the activation of the Creb1, a protein correlated with cell apoptosis, whereas AMO-328-3p ablated the pro-apoptosis effect of silencing lncRNA PFI in MLE-12 cells. While miR-328-3p could also ablate the function of lncRNA PFI in bleomycin treated human lung epithelial cells. Enhanced expression of lncRNA PFI reversed the LPS-induced lung injury in mice. Overall, these data reveal that lncRNA PFI mitigated acute lung injury through miR-328-3p/Creb1 pathway in alveolar epithelial cells.

Long non-coding RNA KCND1 protects hearts from hypertrophy by targeting YBX1.

Cardiac hypertrophy is a common structural remodeling in many cardiovascular diseases. Recently, long non-coding RNAs (LncRNAs) were found to be involved in the physiological and pathological processes of cardiac hypertrophy. In this study, we found that LncRNA KCND1 (LncKCND1) was downregulated in both transverse aortic constriction (TAC)-induced hypertrophic mouse hearts and Angiotensin II (Ang II)-induced neonatal mouse cardiomyocytes. Further analyses showed that the knockdown of LncKCND1 impaired cardiac mitochondrial function and led to hypertrophic changes in cardiomyocytes. In contrast, overexpression of LncKCND1 inhibited Ang II-induced cardiomyocyte hypertrophic changes. Importantly, enhanced expression of LncKCND1 protected the heart from TAC-induced pathological cardiac hypertrophy and improved heart function in TAC mice. Subsequent analyses involving mass spectrometry and RNA immunoprecipitation assays showed that LncKCND1 directly binds to YBX1. Furthermore, overexpression of LncKCND1 upregulated the expression level of YBX1, while silencing LncKCND1 had the opposite effect. Furthermore, YBX1 was downregulated during cardiac hypertrophy, whereas overexpression of YBX1 inhibited Ang II-induced cardiomyocyte hypertrophy. Moreover, silencing YBX1 reversed the effect of LncKCND1 on cardiomyocyte mitochondrial function and its protective role in cardiac hypertrophy, suggesting that YBX1 is a downstream target of LncKCND1 in regulating cardiac hypertrophy. In conclusion, our study provides mechanistic insights into the functioning of LncKCND1 and supports LncKCND1 as a potential therapeutic target for pathological cardiac hypertrophy.

Tumor PKCδ instigates immune exclusion in EGFR-mutated non-small cell lung cancer.

BACKGROUND: The recruitment of a sufficient number of immune cells to induce an inflamed tumor microenvironment (TME) is a prerequisite for effective response to cancer immunotherapy. The immunological phenotypes in the TME of EGFR-mutated lung cancer were characterized as non-inflamed, for which immunotherapy is largely ineffective. METHODS: Global proteomic and phosphoproteomic data from lung cancer tissues were analyzed aiming to map proteins related to non-inflamed TME. The ex vivo and in vivo studies were carried out to evaluate the anti-tumor effect. Proteomics was applied to identify the potential target and signaling pathways. CRISPR-Cas9 was used to knock out target genes. The changes of immune cells were monitored by flow cytometry. The correlation between PKCδ and PD-L1 was verified by clinical samples. RESULTS: We proposed that PKCδ, a gatekeeper of immune homeostasis with kinase activity, is responsible for the un-inflamed phenotype in EGFR-mutated lung tumors. It promotes tumor progression by stimulating extracellular matrix (ECM) and PD-L1 expression which leads to immune exclusion and assists cancer cell escape from T cell surveillance. Ablation of PKCδ enhances the intratumoral penetration of T cells and suppresses the growth of tumors. Furthermore, blocking PKCδ significantly sensitizes the tumor to immune checkpoint blockade (ICB) therapy (αPD-1) in vitro and in vivo model. CONCLUSIONS: These findings revealed that PKCδ is a critical switch to induce inflamed tumors and consequently enhances the efficacy of ICB therapy in EGFR-mutated lung cancer. This opens a new avenue for applying immunotherapy against recalcitrant tumors.

Endocytosis of Peptidase Inhibitor SerpinE2 promotes Myocardial Fibrosis through activating ERK1/2 and ß-catenin Signaling Pathways.

Cardiac fibrosis is one of the common pathological processes in many cardiovascular diseases characterized by excessive extracellular matrix deposition. SerpinE2 is a kind of protein that inhibits peptidase in extracellular matrix and up-regulated tremendously in mouse model of cardiac fibrosis induced by pressure-overloaded via transverse aortic constriction (TAC) surgery. However, its effect on cardiac fibroblasts (CFs), collagen secretion and the underlying mechanism remains unclear. In this study, DyLight® 488 green fluorescent dye or His-tagged proteins were used to label the exogenous serpinE2 protein. It was showed that extracellular serpinE2 translocated into CFs by low-density lipoprotein receptor-related protein 1 (LRP1) and urokinase plasminogen activator receptor (uPAR) of cell membrane through endocytosis. Knockdown of LRP1 or uPAR reduced the level of serpinE2 in CFs and down-regulated the collagen expression. Inhibition of the endocytosis of serpinE2 could inhibit ERK1/2 and ß-catenin signaling pathways and subsequently attenuated collagen secretion. Knockdown of serpinE2 attenuates cardiac fibrosis in TAC mouse. We conclude that serpinE2 could be translocated into cardiac fibroblasts due to endocytosis through directly interact with the membrane protein LRP1 and uPAR, and this process activated the ERK1/2, ß-catenin signaling pathways, consequently promoting collagen production.