Two distinct skeletal muscle microRNA signatures revealing the complex mechanism of sporadic ALS

Exploring dysregulated miRNAs in ALS: implications for disease pathogenesis and early diagnosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease marked by motor neuron degeneration, leading to muscle weakness and paralysis, with no effective treatments available. Early diagnosis could slow disease progression and optimize treatment. MicroRNAs (miRNAs) are being investigated as potential biomarkers due to their regulatory roles in cellular processes and stability in biofluids. However, variability across studies complicates their diagnostic utility in ALS. This study aims to identify significantly dysregulated miRNAs in ALS through meta-analysis to elucidate disease mechanisms and improve diagnostic strategies.

METHODS

We systematically searched PubMed, Google Scholar, and the Cochrane Library, following predefined inclusion and exclusion criteria. The primary effect measure was the standardized mean difference (SMD) with a 95% confidence interval, analyzed using a random-effects model. Additionally, we used network pharmacology to examine the targets of dysregulated miRNAs and their roles in ALS pathology.

RESULTS

Analysing 34 studies, we found significant upregulation of hsa-miR-206, hsa-miR-133b, hsa-miR-23a, and hsa-miR-338-3p, and significant downregulation of hsa-miR-218, hsa-miR-21-5p, and hsa-let-7b-5p in ALS patients. These miRNAs are involved in ALS pathophysiology, including stress granule formation, nuclear pore complex, SMCR8 and Sig1R dysfunction, histone methyltransferase complex alterations, and MAPK signaling perturbation, highlighting their critical role in ALS progression.

CONCLUSION

This study identifies several dysregulated miRNAs in ALS patients, offering insights into their role in the disease and potential as diagnostic biomarkers. These findings enhance our understanding of ALS mechanisms and may inform future diagnostic strategies. Validating these results and exploring miRNA-based interventions are crucial for improving ALS diagnosis and treatment outcomes.

Cancer-secreted exosomal miR-1825 induces angiogenesis to promote colorectal cancer metastasis

BACKGROUND

Angiogenesis is one of the important factors related to tumorigenesis, invasion, and metastasis. Cancer-secreted exosomes are essential mediators of intercellular cross-talk and participate in angiogenesis and metastasis. Unveiling the mechanism of angiogenesis is an important way to develop anti-angiogenesis therapeutic strategies to against cancer progression.

METHODS

miR-1825 expression and relationship with microvascular density were validated in colorectal cancer (CRC) by in situ hybridization (ISH) staining and immunohistochemistry (IHC). Sequential differential centrifugation, transmission electron microscopy, and western blotting analysis were used to extract and characterize exosomes. The effort of exosomal miR-1825 on endothelial cells was examined by transwell assay, wound healing assay, tube formation assay, and aortic ring assay. The relationship of miR-1825, ING1 and the downstream pathway were analyzed by western blot, RT-PCR, Immunofluorescence, and dual-luciferase reporter system analysis.

RESULTS

Exosomal miR-1825 is associated with angiogenesis in CRC and is enriched in exosomes extracted from the serum of CRC patients. The CRC-secreted exosomal miR-1825 can be transferred into vascular endothelial cells, promoting endothelial cell migration and tube formation in vitro, and facilitating angiogenesis and tumor metastasis in vivo. Mechanistically, exosomal miR-1825 regulates angiogenesis and tumor metastasis by suppressing inhibitor of growth family member 1 (ING1) and activating the TGF-β/Smad2/Smad3 signaling pathway in the recipient HUVECs.

CONCLUSIONS

Our study demonstrated the CRC-secreted exosomal miR-1825 could be transferred to vascular endothelial cells, subsequently leads to the inhibition of ING1 and the activation of the TGF-β/Smad2/Smad3 signaling pathway, thereby promoting angiogenesis and liver metastasis in CRC. Exosomal miR-1825 is thus a potential diagnostic and therapeutic target for CRC patients.

Comprehensive analysis of the circRNA expression profile and circRNA-miRNA-mRNA network in pelvic organ prolapse

Pelvic organ prolapse (POP) is a common gynecological disease caused by pathological defects, lesions, or mechanical weakening of the support structures of the pelvic floor. However, its pathogenesis is unclear. Circular RNAs (circRNAs) are covalently closed, endogenous biomolecules, which are thought to play an important role on skeletal muscle development by regulating gene expression. In this study, five pairs of peripheral blood samples from control and POP groups were used for circRNA sequencing analysis to obtain differential expression profiles. A total of 75 differentially expressed circRNAs (DEcircRNAs) were identified (fold change >2.0, P < 0.05). Furthermore, RT-qPCR confirmed that the expression levels of two circRNAs (hsa_circ_0067962 and hsa_circ_0057051) were significantly lower in the POP group. The two validated DEcircRNAs were abundantly involved in the collagen catabolic process. The circRNA-miRNA-mRNA network of two DEcircRNAs comprised nine mRNAs, which indicated that hsa_circ_0067962 and hsa_circ_0057051 may be involved in the pathogenesis of POP by regulating these nine mRNAs.

CircTBC1D22A inhibits the progression of colorectal cancer through autophagy regulated via miR-1825/ATG14 axis

Distant metastasis is the main cause of death in patients with colorectal cancer (CRC). A better understanding of the mechanisms of metastasis can greatly improve the outcome of patients with CRC. Accumulating evidence suggests that circRNA plays pivotal roles in cancer progression and metastasis, especially acting as a miRNA sponge to regulate the expression of the target gene. A public database bioinformatics analysis found that miR-1825 was highly expressed in CRC tissues. In this study, miR-1825 was highly expressed in CRC tissues, which was positively correlated with lymph node metastasis and distant metastasis. In vitro and in vivo experiments confirmed that miR-1825 was positively correlated with the proliferation and migration of CRC cells. This event can be inhibited by circTBC1D22A. CircTBC1D22A can directly interact with miR-1825 and subsequently act as a miRNA sponge to regulate the expression of the target gene ATG14, which collectively advances the autophagy-mediated progression and metastasis of CRC.

Epigenetic Changes in Prion and Prion-like Neurodegenerative Diseases: Recent Advances, Potential as Biomarkers, and Future Perspectives

Prion diseases are transmissible spongiform encephalopathies (TSEs) caused by a conformational conversion of the native cellular prion protein (PrP^C) to an abnormal, infectious isoform called PrP^Sc. Amyotrophic lateral sclerosis, Alzheimer’s, Parkinson’s, and Huntington’s diseases are also known as prion-like diseases because they share common features with prion diseases, including protein misfolding and aggregation, as well as the spread of these misfolded proteins into different brain regions. Increasing evidence proposes the involvement of epigenetic mechanisms, namely DNA methylation, post-translational modifications of histones, and microRNA-mediated post-transcriptional gene regulation in the pathogenesis of prion-like diseases. Little is known about the role of epigenetic modifications in prion diseases, but recent findings also point to a potential regulatory role of epigenetic mechanisms in the pathology of these diseases. This review highlights recent findings on epigenetic modifications in TSEs and prion-like diseases and discusses the potential role of such mechanisms in disease pathology and their use as potential biomarkers.