The Novel Methylation Biomarker SCARA5 Sensitizes Cancer Cells to DNA Damage Chemotherapy Drugs in NSCLC

α-Ketoglutarate plays an inflammatory inhibitory role by regulating scavenger receptor class a expression through N6-methyladenine methylation during sepsis

Sepsis arises from an uncontrolled inflammatory response triggered by infection or stress, accompanied by alteration in cellular energy metabolism, and a strong correlation exists between these factors. Alpha-ketoglutarate (α-KG), an intermediate product of the TCA cycle, has the potential to modulate the inflammatory response and is considered a crucial link between energy metabolism and inflammation. The scavenger receptor (SR-A5), a significant pattern recognition receptor, assumes a vital function in anti-inflammatory reactions. In the current investigation, we have successfully illustrated the ability of α-KG to mitigate inflammatory factors in the serum of septic mice and ameliorate tissue damage. Additionally, α-KG has been shown to modulate metabolic reprogramming and macrophage polarization. Moreover, our findings indicate that the regulatory influence of α-KG on sepsis is mediated through SR-A5. We also elucidated the mechanism by which α-KG regulates SR-A5 expression and found that α-KG reduced the N6-methyladenosine level of macrophages by up-regulating the m6A demethylase ALKBH5. α-KG plays a crucial role in inhibiting inflammation by regulating SR-A5 expression through m6A demethylation during sepsis. The outcomes of this research provide valuable insights into the relationship between energy metabolism and inflammation regulation, as well as the underlying molecular regulatory mechanism.

Paeonol upregulates expression of tumor suppressors TNNC1 and SCARA5, exerting anti-tumor activity in non-small cell lung cancer cells

Paeonol, a naturally bioactive phenolic ingredient predominantly isolated from Paeonia suffruticosa, has recently garnered significant interest as an anti-tumor agent against diverse carcinomas including non-small cell lung cancer (NSCLC). However, the anti-tumor mechanism of paeonol in NSCLC remains unclear. Cell viability, caspase-3 activity, and apoptosis were evaluated using CCK-8 assay, Caspase-3 Colorimetric Assay Kit, and flow cytometry analysis, respectively. GSE186218 was downloaded from NCBI Gene Expression Omnibus (GEO). The common genes were screened using GEO2R and Draw Venn Diagram software. Expression of troponin C type 1 (TNNC1), scavenger receptor class A member 5 (SCARA5), phosphorylated protein kinase B (AKT) (p-AKT) and AKT was examined using GEPIA database, qRT-PCR and western blot analysis. Paeonol treatment concentration-dependently inhibited cell viability and increased caspase-3 activity and apoptotic rate in NSCLC cells. Only 5 overlapping genes including TNNC1 and SCARA5 were obtained among 232 upregulated genes in GSE186218, 200 underexpressed genes in TCGA-LUAD, and 200 underexpressed genes in TCGA-LUSC according to the Venn diagram software. TNNC1 and SCARA5, two known tumor suppressors, were significantly downregulated in LUAD and LUSC tissues and NSCLC cells. Paeonol dose-dependently upregulated TNNC1 and SCARA5 expression in NSCLC cells. Paeonol suppressed the AKT pathway by upregulating TNNC1 and SCARA5 expression. AKT inhibitor attenuated the effects of TNNC1 or SCARA5 knockdown on the anti-tumor activity of paeonol. In conclusion, paeonol exhibited anti-cancer activity in NSCLC cells through inactivating the AKT pathway by upregulating TNNC1 or SCARA5.

Exploring the interplay between methylation patterns and non-coding RNAs in non-small cell lung cancer: Implications for pathogenesis and therapeutic targets

Lung cancer is a global public health issue, with non-small cell lung cancer (NSCLC) accounting for 80-85 % of cases. With over two million new diagnoses annually, understanding the complex evolution of this disease is crucial. The development of lung cancer involves a complex interplay of genetic, epigenetic, and environmental factors, leading the key oncogenes and tumor suppressor genes to disorder, and activating the cancer related signaling pathway. Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNA (lncRNAs), and circular RNA (circRNAs) are unique RNA transcripts with diverse biological functions. These ncRNAs are generated through genome transcription and play essential roles in cellular processes. Epigenetic modifications such as DNA methylation, N6-methyladenosine (m6A) modification, and histone methylation have gained significant attention in NSCLC research. The complexity of the interactions among these methylation modifications and ncRNAs contribute to the precise regulation of NSCLC development. This review comprehensively summarizes the associations between ncRNAs and different methylation modifications and discusses their effects on NSCLC. By elucidating these relationships, we aim to advance our understanding of NSCLC pathogenesis and identify potential therapeutic targets for this devastating disease.

m6A-mediated upregulation of lncRNA RMRP boosts the progression of bladder cancer via epigenetically suppressing SCARA5

Aim: This study aimed to elucidate the relationship between SCARA5 and RMRP in bladder cancer and their underlying mechanism. Methods: Biological functions were evaluated using cell-counting kit 8 assay, 5-ethynyl-2'-deoxyuridine incorporation, wound healing and Transwell assays. RNA immunoprecipitation, RNA pull-down and chromatin immunoprecipitation were employed. A xenograft tumor model in nude mice was also conducted. Results & conclusion: RMRP and SCARA5 exhibited an inverse correlation. Downregulation of RMRP significantly suppressed bladder cancer cell proliferation, migration and invasion, which was reversed by SCARA5 overexpression. RMRP recruited DNA methyltransferases to the promoter region of SCARA5, thereby triggering the methylation of the SCARA5 promoter to epigenetically suppress its expression. Our findings elucidate the machinery by which RMRP, stabilized by METTL3, exerts a promoter role in bladder cancer tumorigenesis by triggering SCARA5 methylation.

Arachidonate lipoxygenases 5 is a novel prognostic biomarker and correlates with high tumor immune infiltration in low-grade glioma

Objective: To investigate the prognostic value of arachidonate lipoxygenases 5 (ALOX5) expression and methylation, and explore the immune functions of arachidonate lipoxygenases 5 expression in low-grade glioma (LGG). Materials and Methods: Using efficient bioinformatics approaches, the differential expression of arachidonate lipoxygenases 5 and the association of its expression with clinicopathological characteristics were evaluated. Then, we analyzed the prognostic significance of arachidonate lipoxygenases 5 expression and its methylation level followed by immune cell infiltration analysis. The functional enrichment analysis was conducted to determine the possible regulatory pathways of arachidonate lipoxygenases 5 in low-grade glioma. Finally, the drug sensitivity analysis was performed to explore the correlation between arachidonate lipoxygenases 5 expression and chemotherapeutic drugs. Results: arachidonate lipoxygenases 5 mRNA expression was increased in low-grade glioma and its expression had a notable relation with age and subtype (p < 0.05). The elevated mRNA level of arachidonate lipoxygenases 5 could independently predict the disease-specific survival (DSS), overall survival (OS), and progression-free interval (PFI) (p < 0.05). Besides, arachidonate lipoxygenases 5 expression was negatively correlated with its methylation level and the arachidonate lipoxygenases 5 hypomethylation led to a worse prognosis (p < 0.05). The arachidonate lipoxygenases 5 expression also showed a positive connection with immune cells, while low-grade glioma patients with higher immune cell infiltration had poor survival probability (p < 0.05). Further, arachidonate lipoxygenases 5 might be involved in immune- and inflammation-related pathways. Importantly, arachidonate lipoxygenases 5 expression was negatively related to drug sensitivity. Conclusion: arachidonate lipoxygenases 5 might be a promising biomarker, and it probably occupies a vital role in immune cell infiltration in low-grade glioma.

Sarcopenia in pulmonary diseases is associated with elevated sarcoplasmic reticulum stress and myonuclear disorganization

Chronic obstructive pulmonary disease (COPD) is frequently associated with age-related muscle loss or sarcopenia. However, the exact molecular mechanism of muscle loss in COPD remains elusive. We investigated the association of chronic dysregulation of sarcoplasmic reticulum (SR) protein homeostasis (a condition called SR stress) and myonuclear disorganization with sarcopenia in patients with COPD. Markers of SR stress and their downstream consequences, including apoptosis and inflammation, were upregulated in patients with COPD. The maximal SR Ca²⁺ ATPase (SERCA) activity was significantly reduced in advanced COPD as compared to healthy controls. Single muscle fiber diameter and cytoplasmic domain per myonucleus were significantly smaller in patients with advanced COPD than in healthy controls. Increased disruption of myonuclear organization was found in the COPD patients as compared to healthy controls. These changes in SR dysfunction were accompanied by elevated global levels of oxidative stress, including lipid peroxidation and mitochondrial reactive oxygen species (ROS) production. Altogether, our data suggest that muscle weakness in advanced COPD is in part associated with the disruption of SR protein and calcium homeostasis and their pathological consequences.

PLAUR as a Potential Biomarker Associated with Immune Infiltration in Bladder Urothelial Carcinoma

Background

Bladder urothelial carcinoma (BLCA) is one of the most lethal and aggressive malignancies of genitourinary system that affects human health. The urokinase plasminogen activator receptor (PLAUR) plays essential roles in tumorigenesis and immune modulation, and its aberrant expression is closely correlated with cancer progression. However, whether PLAUR has the potential to be one promising biomarker or immunotherapy target for BLCA is unknown.

Methodology

Various online databases were applied to assess the expression profile and prognostic value of PLAUR, as well as its correlation with immune infiltration in BLCA, including Oncomine, PrognoScan, TCGA, cBioPortal, TIMER, TISIDB, UALCAN, and MethSurv. The expression of PLAUR in BLCA was confirmed with ELISA assay for serum samples and immunohistochemistry for tissue samples.

Results

The results showed that the expression of PLAUR was elevated in BLCA, which was further confirmed by ELISA and immunohistochemistry. Patients with higher PLAUR level were predicted to have lower overall survival and disease specific survival rates, which were not impacted by the genetic alterations of PLAUR. In addition, the expression of PLAUR was positively associated with immune infiltration, and also the expression levels of gene markers of various immune cells. The negative correlation between PLAUR expression and PLAUR methylation level was observed, among which PLAUR expression was positively correlated with the abundance of 28 kinds of tumor-infiltrating lymphocytes, while PLAUR methylation level was negatively correlated with the abundance of 11 types of tumor-infiltrating lymphocytes. Moreover, the methylation level of PLAUR was closely correlated with patients’ clinicopathological features, and hypomethylation of PLAUR was associated with better outcomes of BLCA patients.

Conclusion

These findings suggested that PLAUR had the potential to serve as a valuable detection and prognostic biomarker or immunotherapeutic target for BLCA.