IκBα targeting promotes oxidative stress-dependent cell death

Biological role of mitochondrial TLR4-mediated NF-κB signaling pathway in central nervous system injury

Previous studies suggested that central nervous system injury is often accompanied by the activation of Toll-like receptor 4/NF-κB pathway, which leads to the upregulation of proapoptotic gene expression, causes mitochondrial oxidative stress, and further aggravates the inflammatory response to induce cell apoptosis. Subsequent studies have shown that NF-κB and IκBα can directly act on mitochondria. Therefore, elucidation of the specific mechanisms of NF-κB and IκBα in mitochondria may help to discover new therapeutic targets for central nervous system injury. Recent studies have suggested that NF-κB (especially RelA) in mitochondria can inhibit mitochondrial respiration or DNA expression, leading to mitochondrial dysfunction. IκBα silencing will cause reactive oxygen species storm and initiate the mitochondrial apoptosis pathway. Other research results suggest that RelA can regulate mitochondrial respiration and energy metabolism balance by interacting with p53 and STAT3, thus initiating the mitochondrial protection mechanism. IκBα can also inhibit apoptosis in mitochondria by interacting with VDAC1 and other molecules. Regulating the biological role of NF-κB signaling pathway in mitochondria by targeting key proteins such as p53, STAT3, and VDAC1 may help maintain the balance of mitochondrial respiration and energy metabolism, thereby protecting nerve cells and reducing inflammatory storms and death caused by ischemia and hypoxia.

m6A/HOXA10-AS/ITGA6 axis aggravates oxidative resistance and malignant progression of laryngeal squamous cell carcinoma through regulating Notch and Keap1/Nrf2 pathways

As the second most prevalent malignant tumor of head and neck, laryngeal squamous cell carcinoma (LSCC) imposes a substantial health burden on patients worldwide. Within recent years, resistance to oxidative stress and N6-methyladenosine (m6A) of RNA have been proved to be significantly involved in tumorigenesis. In current study, we investigated the oncogenic role of m6A modified long non coding RNAs (lncRNAs), specifically HOXA10-AS, and its downstream signaling pathway in the regulation of oxidative resistance in LSCC. Bioinformatics analysis revealed that heightened expression of HOXA10-AS was associated with the poor prognosis in LSCC patients, and N (6)-Methyladenosine (m6A) methyltransferase-like 3 (METTL3) was identified as a factor in promoting m6A modification of HOXA10-AS and further intensify its RNA stability. Mechanistically, HOXA10-AS was found to play as a competitive endogenous RNA (ceRNA) by sequestering miR-29 b-3p and preventing its downregulation of Integrin subunit alpha 6 (ITGA6), ultimately enhancing the oxidative resistance of tumor cells and promoting the malignant progression of LSCC. Furthermore, our research elucidated the mechanism by which ITGA6 accelerates Keap1 proteasomal degradation via enhancing TRIM25 expression, leading to increased Nrf2 stability and exacerbating its aberrant activation. Additionally, we demonstrated that ITGA6 enhances γ-secretase-mediated Notch signaling activation, ultimately promoting RBPJ-induced TRIM25 transcription. The current study provides the evidence supporting the effect of m6A modified HOXA10-AS and its downstream miR-29 b-3p/ITGA6 axis on regulating oxidative resistance and malignant progression in LSCC through the Notch and Keap1/Nrf2 pathways, and proposed that targeting this axis holds promise as a potential therapeutic approach for treating LSCC.

Advance in the pharmacological effects of quercetin in modulating oxidative stress and inflammation related disorders

Numerous pharmacological effects of quercetin have been illustrated, including antiinflammation, antioxidation, and anticancer properties. In recent years, the antioxidant activity of quercetin has been extensively reported, in particular, its impacts on glutathione, enzyme activity, signaling transduction pathways, and reactive oxygen species (ROS). Quercetin has also been demonstrated to exert a striking antiinflammatory effect mainly by inhibiting the production of cytokines, reducing the expression of cyclooxygenase and lipoxygenase, and preserving the integrity of mast cells. By regulating oxidative stress and inflammation, which are regarded as two critical processes involved in the defense and regular physiological operation of biological systems, quercetin has been validated to be effective in treating a variety of disorders. Symptoms of these reactions have been linked to degenerative processes and metabolic disorders, including metabolic syndrome, cardiovascular, neurodegeneration, cancer, and nonalcoholic fatty liver disease. Despite that evidence demonstrates that antioxidants are employed to prevent excessive oxidative and inflammatory processes, there are still concerns regarding the expense, accessibility, and side effects of agents. Notably, natural products, especially those derived from plants, are widely accessible, affordable, and generally safe. In this review, the antioxidant and antiinflammatory abilities of the active ingredient quercetin and its application in oxidative stress-related disorders have been outlined in detail.

Targeting the mitochondria in chronic respiratory diseases

Mitochondria are one of the basic essential components for eukaryotic life survival. It is also the source of respiratory ATP. Recently published studies have demonstrated that mitochondria may have more roles to play aside from energy production. There is an increasing body of evidence which suggest that mitochondrial activities involved in normal and pathological states contribute to significant impact to the lung airway morphology and epithelial function in respiratory diseases such as asthma, COPD, and lung cancer. This review summarizes the pathophysiological pathways involved in asthma, COPD, lung cancer and highlights potential treatment strategies that target the malfunctioning mitochondria in such ailments. Mitochondria are responsive to environmental stimuli such as infection, tobacco smoke, and inflammation, which are essential in the pathogenesis of respiratory diseases. They may affect mitochondrial shape, protein production and ultimately cause dysfunction. The impairment of mitochondrial function has downstream impact on the cytosolic components, calcium control, response towards oxidative stress, regulation of genes and proteins and metabolic activities. Several novel compounds and alternative medicines that target mitochondria in asthma and chronic lung diseases have been discussed here. Moreover, mitochondrial enzymes or proteins that may serve as excellent therapeutic targets in COPD are also covered. The role of mitochondria in respiratory diseases is gaining much attention and mitochondria-based treatment strategies and personalized medicine targeting the mitochondria may materialize in the near future. Nevertheless, more in-depth studies are urgently needed to validate the advantages and efficacy of drugs that affect mitochondria in pathological states.

Shedding Light on NF-κB Functions in Cellular Organelles

NF-κB is diffusely recognized as a transcriptional factor able to modulate the expression of various genes involved in a broad spectrum of cellular functions, including proliferation, survival and migration. NF-κB is, however, also acting outside the nucleus and beyond its ability to binds to DNA. NF-κB is indeed found to localize inside different cellular organelles, such as mitochondria, endoplasmic reticulum, Golgi and nucleoli, where it acts through different partners in mediating various biological functions. Here, we discuss the relationship linking NF-κB to the cellular organelles, and how this crosstalk between cellular organelles and NF-κB signalling may be evaluated for anticancer therapies.

Comprehensive Analysis of Alteration Landscape and Its Clinical Significance of Mitochondrial Energy Metabolism Pathway-Related Genes in Lung Cancers

Background

Mitochondria are the energy factories of cells. The abnormality of mitochondrial energy metabolism pathways is closely related to the occurrence and development of lung cancer. The abnormal genes in mitochondrial energy metabolism pathways might be the novel targets and biomarkers to diagnose and treat lung cancers.

Method

Genes in major mitochondrial energy metabolism pathways were obtained from the KEGG database. The transcriptomic, mutation, and clinical data of lung cancers were obtained from The Cancer Genome Atlas (TCGA) database. Genes and clinical biomarkers were mined that affected lung cancer survival. Gene enrichment analysis was performed with ClusterProfiler and the gene set enrichment analysis (GSEA). STRING database and Cytoscape were used for protein-protein interaction (PPI) analysis. The diagnostic biomarker pattern of lung cancer was optimized, and its accuracy was verified with 10-fold cross-validation. The four genes screened by logistic regression model were verified by western blot in 5 pairs of lung cancer specimens collected in hospital.

Results

In total, 188 mitochondrial energy metabolism pathway-related genes (MMRGs) were included in this study. GSEA analysis found that MMRGs in the lung cancer group were mainly enriched in the metabolic pathway of oxidative phosphorylation and electron respiratory transport chain compared to the control group. Age did not affect the mutation frequency of MMRGs. Comparative analysis of these 188 MMRGs identified 43 differentially expressed MMRGs (24 upregulated and 19 downregulated) in the lung cancer group compared to the control group. The survival analysis of these 43 differentially expressed MMRGs found that the survival time was better in the low-expressed GAPDHS group than that in the high-expressed GAPDHS group of lung cancers. The advanced age, high expression of GAPDHS, low expressions of ACSBG1 and CYP4A11, and ACOX3 mutation were biomarkers of poor prognosis in lung cancers. PPI analysis showed that proteins such as GAPDH and GAPDHS interacted with many proteins in mitochondrial metabolic pathways. A four-MMRG-signature model (y = 0.0069∗ACADL - 0.001∗ALDH18A1 - 0.0405∗CPT1B + 0.0008∗PPARG - 1.625) was established to diagnose lung cancer with the accuracy up to 98.74%, AUC value up to 0.992, and a missed diagnosis rate of only 0.6%. Western blotting showed that ALDH18A1 and CPT1B proteins were significantly overexpressed in the lung cancer group (p < 0.05), and ACADL and PPARG proteins were slightly underexpressed in the lung cancer group (p < 0.05), which were consistent with the results of their corresponding mRNA expressions.

Conclusion

Mitochondrial energy metabolism pathway alterations are the important hallmarks of lung cancer. Age did not increase the risk of MMRG mutation. High expression of GAPDHS, low expression of ACSBG1, low expression of CYP4A11, mutated ACOX3, and old age predict a poor prognosis of lung cancer. Four differentially expressed MMRGs (ACADL, ALDH18A1, CPT1B, and PPARG) established a logistic regression model, which could effectively diagnose lung cancer. At the protein level, ALDH18A1 and CPT1B were significantly upregulated, and ACADL and PPARG were slightly underexpressed, in the lung cancer group compared to the control group, which were consistent with the results of their corresponding mRNA expressions.

NF-κB-Dependent and -Independent (Moonlighting) IκBα Functions in Differentiation and Cancer

IκBα is considered to play an almost exclusive role as inhibitor of the NF-κB signaling pathway. However, previous results have demonstrated that SUMOylation imposes a distinct subcellular distribution, regulation, NF-κB-binding affinity and function to the IκBα protein. In this review we discuss the main alterations of IκBα found in cancer and whether they are (most likely) associated with NF-κB-dependent or NF-κB-independent (moonlighting) activities of the protein.