Cellular signalling最新文献

Background

Our prior research determined that USP7 exacerbates myocardial injury. Additionally, existing studies indicate a strong connection between USP7 and ferroptosis. However, the influence of USP7 on ferroptosis-mediated myocardial infarction (MI) remains unclear. Given these findings, we are particularly interested in USP7's regulatory role in ferroptosis-mediated MI and its underlying mechanisms.

Methods

In this study, we established MI models and lentivirus-transfected groups to inhibit USP7 expression both in vivo and in vitro. Cardiac function was detected with Echocardiography. TTC and HE staining were employed to assess myocardial alterations. The expression of ferroptosis markers (PTGS2, ACSL4, GPX4) were analyzed by RT-qPCR and Western blotting. Flow cytometry and ELISA were used for measuring Fe²⁺, lipid ROS, GSH, and GSSG levels. TEM and Prussian blue staining were used to observe mitochondrial alterations and iron deposition. RT-qPCR, Western blotting, and immunofluorescence were conducted to analyze Keap1, Nrf2, and nuclear Nrf2 expression in vitro and in vivo.

Results

In the MI model group, USP7 expression significantly increased, worsening ferroptosis-mediated MI. Conversely, in the USP7-inhibited group, activation of the Keap1-Nrf2 signaling pathway improved ferroptosis-mediated MI outcomes. In vitro, the MI model exhibited a marked decline in cardiomyocyte viability and notable mitochondrial damage. However, these issues improved in the USP7-inhibited groups. In vivo, USP7 intensified MI and iron deposition within the MI model group, with decreased values of LVEF, LVFS, SV, LVAWd, and LVPWs, all of which showed improvement in the USP7-inhibited group, except for LVPWd and LVPWs, which showed no significant variation. Importantly, both the in vitro and in vivo experiments revealed analogous results: a reduction in Keap1 expression and an increase in both Nrf2 and nuclear Nrf2 post USP7 inhibition. Additionally, GPX4 expression decreased while PTGS2 and ACSL4 expressions increased. Notably, concentrations of Fe²⁺, lipid ROS, GSH, and GSSG significantly decreased.

Conclusion

In vitro and in vivo studies have found that inhibition of USP7 attenuates iron deposition and suppresses oxidative stress, resulting in amelioration of ferroptosis-induced MI.

Background

Methods

Results

Conclusion

Sunitinib resistance presents a significant challenge in the treatment of clear cell renal cell carcinoma (ccRCC). The role of TRIB3, a newly identified oncogene, in tumor drug resistance has been widely studied. However, the mechanism by which TRIB3 contributes to sunitinib resistance in ccRCC has not been previously explored. This study aimed to investigate the mechanism through which TRIB3 regulates ferroptosis to increase the susceptibility of ccRCC to sunitinib treatment. Bioinformatics analysis and experimental validation revealed that TRIB3 is significantly upregulated in ccRCC tissues and is associated with poor prognosis. Knockdown of TRIB3 using siRNA transfection inhibited the proliferation and migration of ccRCC cells and induced ferroptosis. Following sunitinib treatment, TRIB3 knockdown increased cell sensitivity to sunitinib, enhanced the suppressive impact of sunitinib, and augmented sunitinib-induced ferroptosis. This study demonstrated that TRIB3 knockdown induces ferroptosis by targeting the SLC7A11/GPX4 pathway and enhances therapeutic efficacy of sunitinib for ccRCC, providing new insights and potential strategies to overcome the challenge of sunitinib resistance in ccRCC.

The MAPK and PI3K/AKT/mTOR pathways are aberrantly activated in non-small cell lung cancer (NSCLC) patients, but therapeutic efficacy of NSCLC using trametinib (MEK inhibitor) or BEZ-235 (dual PI3K/mTOR inhibitor) alone is still unsatisfactory. Therefore, in this study, we aimed to determine whether the combination of trametinib with BEZ-235 exerted synergistic effects against NSCLC in both in vitro and in vivo models, and we preliminarily explored the effect of this combination therapy on glucose metabolism. Our results showed that trametinib combined with BEZ-235 could better inhibit cell proliferation and colony formation, induce G0/G1 phase arrest and apoptosis, and suppress cell invasion and migration compared with the single agent. The combination index demonstrated that trametinib and BEZ-235 exerted strong synergistic effects. Additionally, trametinib and BEZ-235 exhibited synergistic antitumor effects in vivo. Furthermore, trametinib and BEZ-235 synergistically downregulated the expression of related proteins in the MAPK and PI3K/AKT/mTOR pathways, and decreased glucose consumption and lactic acid production through suppressing the expressions of glucose transporter 1 (GLUT1) and lactate dehydrogenase A (LDHA). These data imply that simultaneous inhibition of the MAPK and PI3K/AKT/mTOR pathways using trametinib combined with BEZ-235 could synergistically impair glucose metabolism, resulting in an obvious synergistic therapeutic effect against NSCLC.

Cancer cells require plentiful cholesterol for membrane biogenesis and other functional needs due to fast proliferating, leading to the interaction of cholesterol or its metabolites with cancer-related pathways. However, the impact of long-lasting high cholesterol concentrations on tumorigenesis and its underlying mechanisms remains largely unexplored. To the best of our knowledge, this study is the first to establish a cholesterol-resistant ovarian cancer cells, whose intracellular total cholesterol level up to 6–8 mmol/L. We confirmed that high cholesterol facilitated the progression of ovarian cancer in vitro and in vivo. Notably, our findings revealed significant upregulation of collagen type V alpha 1 chain (COL5A1) expression in cholesterol-resistant ovarian cancer cells and human ovarian cancer tissue, which was depended on FAK/Src activation. Mechanistically, PARP1 directly bound to FAK in response to activate FAK/Src/COL5A1 signaling. Intriguingly, COL5A1 depletion significantly impeded the tumorigenesis of these cells, concomitant with a decrease in epithelial-mesenchymal transition (EMT) progression. In conclusion, PARP1/FAK/COL5A1 signaling activation facilitated progression of cholesterol-resistant ovarian cancer cells by promoting EMT, thereby broadening a new therapeutic opportunity.

The renin–angiotensin system (RAS) is a crucial factor in chronic kidney disease (CKD) progression, affecting renal function and contributing significantly to renal tissue inflammation and fibrosis. Activation of the classical ACE/Ang II/AT1 axis exacerbates renal damage, while the ACE2/Ang-(1–7)/Mas axis has shown promise in reducing CKD progression in numerous animal models. Recently, the ACE2/Ang-(1–7)/Mas axis has emerged as a promising target for CKD interventions. This review provides a comprehensive review of the pivotal role of this axis in CKD pathogenesis and systematically examines various molecules and pharmaceutical agents targeting this pathway. This review aims to elucidate potential strategies for delaying or halting CKD progression, offering patients more effective treatment options.

Background

The mechanisms underlying ferroptosis in heart failure (HF) remain incompletely understood.

Methods

This study analyzed the heart failure dataset from the Gene Expression Omnibus to identify differentially expressed ferroptosis-related genes (DFRGs). Key DFRGs were selected using LASSO regression and SVM-RFE machine learning techniques. Their diagnostic accuracy was evaluated via ROC curve analysis. Single-cell sequencing data, heart failure cell, and mouse models were utilized to validate these key DFRGs. Additionally, potential non-coding RNAs targeting these genes were predicted, and analyses for gene set enrichment, immune cell infiltration, and drug targeting were conducted.

Results

A total of 127 DFRGs were identified, with 83 downregulated and 44 upregulated compared to controls. Seven key DFRGs (PTGS2, BECN1, SLC39A14, QSOX1, MLST8, TMSB4X, KDM4A) were identified, showing high diagnostic accuracy (AUC 0.988) in the GSE5406 dataset. GO and KEGG analyses linked these genes to ferroptosis, FoxO signaling, and autophagy pathways. A ceRNA network identified 217 miRNAs and 243 lncRNAs potentially targeting these genes, and 64 drugs were predicted as potential targets. Single-cell sequencing and in vitro experiments revealed differential expression of SLC39A14 and QSOX1, which was further confirmed in vivo.

Conclusion

This study provides novel insights into the role of ferroptosis in heart failure by identifying and validating DFRGs that exhibit differential expression across various cell types. The differential expression patterns of these genes, particularly SLC39A14 and QSOX1, indicate their potential involvement in the pathophysiological mechanisms contributing to HF. These findings offer new insights for the development of targeted therapies for HF.

Glucocorticoid-induced leucine zipper (GILZ) plays a role in cancer cell proliferation in several tumor types. However, in our present study, GILZ was demonstrated to be a metastasis regulator but not a proliferation regulator in non-small cell lung cancer (NSCLC). The overexpression of GILZ had no significant effect on the proliferation of NSCLC cells but inhibited their metastasis by targeting the epithelial-mesenchymal transition pathway. The deacetylase SIRT6, a key regulator of protein stability, can enhance the stability of the GILZ protein by mediating its deacetylation, which prevents ubiquitination and degradation. This process ultimately enhances the inhibitory effect of GILZ on the migration and invasion of NSCLC cells. Thus, GILZ may be a promising new therapeutic target for tumor metastasis.

Purpose

The goal of this research was to explore the role of miR-24-3p in heart failure (HF), with a focus on its impact on the specificity protein 1 (Sp1)/phosphoinositide 3-kinase (PI3K) pathway.

Methods

HF rat and HF cell models were established using doxorubicin(Dox). Cardiac function was assessed through echocardiography, while histological changes were observed via hematoxylin-eosin (HE) staining. To further investigate the underlying mechanisms, HF cell models were treated with either an Sp1 inhibitor or a PI3K inhibitor. Additionally, models with miR-24-3p overexpression or silencing were constructed. N-terminal pro-brain natriuretic peptide (NT-proBNP) levels were determined by ELISA. Cell apoptosis was evaluated using TUNEL staining, and lactate dehydrogenase (LDH) levels were measured by colorimetry. Reactive oxygen species (ROS) production was analyzed using flow cytometry. Related gene and protein expressions were assessed via qRT-PCR and Western blotting. Finally, the relationship between miR-24-3p and Sp1 was confirmed through dual-luciferase assays.

Results

Dox treatment increased the left ventricular internal diameter (LVIDd) while decreasing ejection fraction (EF) and fractional shortening (FS), leading to disorganized cardiomyocyte arrangement, cellular edema, and necrosis in rats. In HF rats, NT-proBNP, Caspase-3, and miR-24-3p expression levels were elevated, whereas Sp1 and PI3K mRNA and protein expression levels were decreased. Similarly, Dox-induced damage in H9c2 cardiomyocytes resulted in increased NT-proBNP, apoptosis, Caspase-3, LDH, ROS, and miR-24-3p expression, along with decreased Sp1 and PI3K expression. Treatment with either Sp1 or PI3K inhibitors exacerbated the Dox-induced cardiomyocyte damage, further elevating NT-proBNP, apoptosis, Caspase-3, LDH, ROS, and miR-24-3p expression levels. Notably, Sp1 inhibition reduced PI3K expression, and PI3K inhibition, in turn, suppressed Sp1 expression. Overexpression of miR-24-3p worsened Dox-induced cardiomyocyte damage, characterized by increased NT-proBNP, apoptosis, Caspase-3, LDH, and ROS expression, alongside reduced Sp1 and PI3K expression. In contrast, silencing miR-24-3p mitigated these detrimental effects and increased Sp1 and PI3K expression. Dual-luciferase assays confirmed that miR-24-3p directly targets Sp1.

Conclusion

Dox induces cardiomyocyte damage, impairs cardiac function, and promotes cardiomyocyte apoptosis and oxidative stress. Silencing miR-24-3p offers a protective effect by activating the Sp1/PI3K signaling pathway in heart failure.