Reticulocalbin 2 as a Potential Biomarker and Therapeutic Target for Atherosclerosis

LncRNA LUCAT1 offers protection against human coronary artery endothelial cellular oxidative stress injury through modulating hsa-miR-6776-5p/LRRC25 axis and activating autophagy flux

BACKGROUND

Coronary artery disease (CAD) has become a dominant economic and health burden worldwide, and the role of autophagy in CAD requires further clarification. In this study, we comprehensively revealed the association between autophagy flux and CAD from multiple hierarchies. We explored autophagy-associated long noncoding RNA (lncRNA) and the mechanisms underlying oxidative stress-induced human coronary artery endothelial cells (HCAECs) injury.

METHODS

(1) Autophagy-related proteins including LC3, p62, Beclin1, ATG5, and ATG7 were immunohistochemical stained in coronary specimens; (2) The levels and function of autophagy in the HCAEC oxidative stress model were evaluated using western blot (WB), transmission electron microscopy (TEM), and mRFP-GFP-LC3 adenovirus transfection experiments; (3) The competing endogenous RNA (ceRNA) network of lncRNA LUCAT1/hsa-miR-6776-5p/LRRC25 axis was constructed and validated; (4) The expression levels of above autophagy-related RNAs in peripheral blood mononuclear cells (PBMCs) were verified by qPCR, and their diagnostic performance was subsequently analyzed using receiver operating characteristic (ROC) analysis.

RESULTS

(1) The expression of LC3, Beclin1, ATG5, and ATG7 demonstrated a consistent decline whereas p62 expression exhibited an opposite increase as atherosclerosis progressed; (2) Autophagy levels was significantly elevated in HCAECs under oxidative stress, while inhibition of the initial stage of autophagy with 3-MA exacerbated cellular damage; (3) The lncRNA LUCAT1/hsa-miR-6776-5p/LRRC25 axis was established through bioinformatic prediction and validated by dual-luciferase reporter assay, which resulted in a significant decrease in autophagy levels in HCAECs; (4) In total, p62, ATG7, lncRNA LUCAT1 and LRRC25 were validated as robust diagnostic biomarkers for CAD.

CONCLUSIONS

Our results delineated the dynamic disruption of the autophagy landscape during the progression of human coronary atherosclerosis and identified the lncRNA LUCAT1/hsa-miR-6776-5p/LRRC25 axis, uncovered through transcriptomic profiling, as a protective mechanism against endothelial cell injury through autophagy activation. Furthermore, we recognized p62, ATG7, lncRNA LUCAT1, and LRRC25 as dependable autophagy-related diagnostic biomarkers in circulating PBMCs, correlating with CAD severity. Collectively, Our findings furnish novel insights into the intricate autophagy landscape at various levels of coronary atherosclerosis and propose potential diagnostic biomarkers, and a theoretical foundation for managing CAD patients.

Upregulation of RCN2 accelerates tumor progression and indicates poor prognosis in OSCC

OBJECTIVE

Oral squamous cell carcinoma (OSCC) is a prevalent cancer of the head and neck region. However, the potential role of RCN2 in OSCC is currently not well understood.

STUDY DESIGN

A series of molecular biology experiments were conducted to explore the mechanism by which RCN2 promotes OSCC growth through protein kinase A (PKA).

RESULTS

Our results revealed a significant increase in RCN2 levels in OSCC tissues. Moreover, OSCC patients with high RCN2 expression had a significantly worse prognosis than those with lower RCN2 expression. Interestingly, PKA activity was increased in RCN2-overexpressing YD-10B cells but reduced in RCN2-knockout Ca9-22 cells. These findings suggest that RCN2-mediated PKA activity is activated in OSCC cells. Moreover, the specific PKA inhibitor H89 significantly reduced the proliferation ability of RCN2-overexpressing Ca9-22 cells. Furthermore, we identified AKT/mTORC as a downstream pathway through which PKA promotes OSCC cell proliferation. The Tumor Immune Estimation Resource database revealed that the expression level of RCN2 was correlated with the infiltration levels of B cells, CD8+ T cells, CD4+ T cells, and neutrophils in the microenvironment of OSCC.

CONCLUSIONS

Our study revealed that RCN2 promotes tumor progression by activating PKA/AKT/mTORC signaling, which suggests that RCN2 may serve as a potential target for OSCC treatment.

The identification of key genes and pathways in polycystic ovary syndrome by bioinformatics analysis of next-generation sequencing data

Background

Polycystic ovary syndrome (PCOS) is a reproductive endocrine disorder. The specific molecular mechanism of PCOS remains unclear. The aim of this study was to apply a bioinformatics approach to reveal related pathways or genes involved in the development of PCOS.

Methods

The next-generation sequencing (NGS) dataset GSE199225 was downloaded from the gene expression omnibus (GEO) database and NGS dataset analyzed is obtained from in vitro culture of PCOS patients’ muscle cells and muscle cells of healthy lean control women. Differentially expressed gene (DEG) analysis was performed using DESeq2. The g:Profiler was utilized to analyze the gene ontology (GO) and REACTOME pathways of the differentially expressed genes. A protein–protein interaction (PPI) network was constructed and module analysis was performed using HiPPIE and cytoscape. The miRNA-hub gene regulatory network and TF-hub gene regulatory network were constructed. The hub genes were validated by using receiver operating characteristic (ROC) curve analysis.

Results

We have identified 957 DEG in total, including 478 upregulated genes and 479 downregulated gene. GO terms and REACTOME pathways illustrated that DEG were significantly enriched in regulation of molecular function, developmental process, interferon signaling and platelet activation, signaling, and aggregation. The top 5 upregulated hub genes including HSPA5, PLK1, RIN3, DBN1, and CCDC85B and top 5 downregulated hub genes including DISC1, AR, MTUS2, LYN, and TCF4 might be associated with PCOS. The hub gens of HSPA5 and KMT2A, together with corresponding predicted miRNAs (e.g., hsa-mir-34b-5p and hsa-mir-378a-5p), and HSPA5 and TCF4 together with corresponding predicted TF (e.g., RCOR3 and TEAD4) were found to be significantly correlated with PCOS.

Conclusions

These study uses of bioinformatics analysis of NGS data to obtain hub genes and key signaling pathways related to PCOS and its associated complications. Also provides novel ideas for finding biomarkers and treatment methods for PCOS and its associated complications.

Excessive mechanical loading promotes osteoarthritis development by upregulating Rcn2

Exposure of articular cartilage to excessive mechanical loading is closely related to the pathogenesis of osteoarthritis (OA). However, the exact molecular mechanism by which excessive mechanical loading drives OA remains unclear. In vitro, primary chondrocytes were exposed to cyclic tensile strain at 0.5 Hz and 10 % elongation for 30 min to simulate excessive mechanical loading in OA. In vivo experiments involved mice undergoing anterior cruciate ligament transection (ACLT) to model OA, followed by interventions on Rcn2 expression through adeno-associated virus (AAV) injection and tamoxifen-induced gene deletion. 10 μL AAV2/5 containing AAV-Rcn2 or AAV-shRcn2 was administered to the mice by articular injection at 1 week post ACLT surgery, and Col2a1-creERT: Rcn2flox/flox mice were injected with tamoxifen intraperitoneally to obtain Rcn2-conditional knockout mice. Finally, we explored the mechanism of Rcn2 affecting OA. Here, we identified reticulocalbin-2 (Rcn2) as a mechanosensitive factor in chondrocytes, which was significantly elevated in chondrocytes under mechanical overloading. PIEZO type mechanosensitive ion channel component 1 (Piezo1) is a critical mechanosensitive ion channel, which mediates the effect of mechanical loading on chondrocytes, and we found that increased Rcn2 could be suppressed through knocking down Piezo1 under excessive mechanical loading. Furthermore, chondrocyte-specific deletion of Rcn2 in adult mice alleviated OA progression in the mice receiving the surgery of ACLT. On the contrary, articular injection of Rcn2-expressing adeno-associated virus (AAV) accelerated the progression of ACLT-induced OA in mice. Mechanistically, Rcn2 accelerated the progression of OA through promoting the phosphorylation and nuclear translocation of signal transducer and activator of transcription 3 (Stat3).

Identification of Endoplasmic Reticulum Stress-Related Biomarkers in Coronary Artery Disease

Coronary artery disease (CAD) is caused by atherosclerotic lesions in the coronary vessels. Endoplasmic reticulum stress (ERS) acts in cardiovascular disease, and its role in CAD is not clear. A total of 13 differentially expressed ERS-related genes (DEERSRGs) in CAD were identified. Functional enrichment analysis demonstrated the DEERSRGs were mainly enriched in endoplasmic reticulum (ER)-related pathways. Then, eight genes (RCN2, HRC, DERL2, RNF183, CRH, TMED2, PPP1R15A, and IL1A) were authenticated as ERS-related biomarkers in CAD by least absolute shrinkage and selection operator (LASSO). The receiver operating characteristic (ROC) analysis showed that the LASSO logistic model constructed based on biomarkers had a better diagnostic effect, which was confirmed by the ANN and GSE23561 datasets. Also, ROC results showed that seven of the eight biomarkers had better diagnostic effects. The nomogram model had good predictive power, and biomarkers were mostly enriched in pathways associated with CAD. The biomarkers were significantly associated with 10 immune cells, and RCN2, DERL2, TMED2, and RNF183 were negatively correlated with most chemokines. Eight biomarkers had significant correlations with both immunoinhibitors and immunostimulators. In addition, eight biomarkers were significantly different in both CAD and control samples, CRH and HRC were upregulated in CAD. The quantitative reverse transcription-polymerase chain reaction (qRT-PCR) showed that RCN2, HRC, DERL2, CRH, and IL1A were consistent with the bioinformatics analysis. RCN2, HRC, DERL2, RNF183, CRH, TMED2, PPP1R15A, and IL1A were identified as biomarkers of CAD. Functional enrichment analysis and immunoassays for biomarkers provide new ideas for the treatment of CAD.

Multiomics profiling of human plasma and cerebrospinal fluid reveals ATN-derived networks and highlights causal links in Alzheimer's disease

INTRODUCTION

This study employed an integrative system and causal inference approach to explore molecular signatures in blood and CSF, the amyloid/tau/neurodegeneration [AT(N)] framework, mild cognitive impairment (MCI) conversion to Alzheimer's disease (AD), and genetic risk for AD.

METHODS

Using the European Medical Information Framework (EMIF)-AD cohort, we measured 696 proteins in cerebrospinal fluid (n = 371), 4001 proteins in plasma (n = 972), 611 metabolites in plasma (n = 696), and genotyped whole-blood (7,778,465 autosomal single nucleotide epolymorphisms, n = 936). We investigated associations: molecular modules to AT(N), module hubs with AD Polygenic Risk scores and APOE4 genotypes, molecular hubs to MCI conversion and probed for causality with AD using Mendelian randomization (MR).

RESULTS

AT(N) framework associated with protein and lipid hubs. In plasma, Proprotein Convertase Subtilisin/Kexin Type 7 showed evidence for causal associations with AD. AD was causally associated with Reticulocalbin 2 and sphingomyelins, an association driven by the APOE isoform.

DISCUSSION

This study reveals multi-omics networks associated with AT(N) and causal AD molecular candidates.