The Clinical Significance of MicroRNAs in Colorectal Cancer Signaling Pathways: A Review

Differential Expression of miRNAs Between Young-Onset and Late-Onset Indian Colorectal Carcinoma Patients

Reports indicate a worldwide increase in the incidence of Early-Onset Colorectal Carcinoma (EOCRC) (<50 years old). In an effort to understand the different modes of pathogenesis in early-onset CRC, colorectal tumors from EOCRC (<50 years old) and Late-Onset patients (LOCRC; >50 years old) were screened to eliminate microsatellite instability (MSI), nuclear β-catenin, and APC mutations, as these are known canonical factors in CRC pathogenesis. Small-RNA sequencing followed by comparative analysis revealed differential expression of 23 miRNAs (microRNAs) specific to EOCRC and 11 miRNAs specific to LOCRC. We validated the top 10 EOCRC DEMs in TCGA-COAD and TCGA-READ cohorts, followed by validation in additional EOCRC and LOCRC cohorts. Our integrated analysis revealed upregulation of hsa-miR-1247-3p and hsa-miR-148a-3p and downregulation of hsa-miR-326 between the two subsets. Experimentally validated targets of the above miRNAs were compared with differentially expressed genes in the TCGA dataset to identify targets with physiological significance in EOCRC development. Our analysis revealed metabolic reprogramming, downregulation of anoikis-regulating pathways, and changes in tissue morphogenesis, potentially leading to anchorage-independent growth and progression of epithelial-mesenchymal transition (EMT). Upregulated targets include proteins present in the basal part of intestinal epithelial cells and genes whose expression is known to correlate with invasion and poor prognosis.

Advances in microRNAs as Emerging Biomarkers for Colorectal Cancer Early Detection and Diagnosis

Colorectal cancer (CRC) remains the second most common cause of cancer-related mortality worldwide, necessitating advancements in early detection and innovative treatment strategies. MicroRNAs (miRNAs), small non-coding RNAs involved in gene regulation, have emerged as crucial players in the pathogenesis of CRC. This review synthesizes the latest findings on miRNA deregulated in precancerous lesions and in CRC. By examining the deregulation patterns of miRNAs across different stages of CRC development, this review highlights their potential as diagnostic tools. We specifically analyse the roles and diagnostic relevance of four miRNAs-miR-15b, miR-21, miR-31, and miR-146a-that consistently exhibit altered expression in CRC. The current knowledge of their role in key oncogenic pathways, drug resistance, and clinical relevance is discussed. Despite challenges posed by the heterogeneity of the research findings on miRNA deregulation and their role in CRC, integrating miRNA diagnostics into current screening methods holds promise for enhancing personalized medicine approaches. This review emphasizes the transformative potential of miRNAs in CRC diagnosis, paving the way for improved patient outcomes and novel therapeutic paradigms.

MiR-5195-3p predicts clinical prognosis and represses colorectal cancer progression by targeting TLR4/MyD88 signaling

BACKGROUND

Recent studies have highlighted the role of miR-5195-3p in suppressing cell growth in various cancers. However, the specific functional impact of miR-5195-3p in colorectal cancer (CRC) remain to be fully clarified. The importance of miR-5195-3p in CRC was evaluated, aiming to uncover its underlying molecular mechanism and identify it as a potential therapeutic target for CRC.

RESULTS

Our research has shown that miR-5195-3p is markedly under-expressed in CRC tissues and cell cultures, with its reduced presence associated with a higher TNM stage, lymphatic invasion, and unfavorable survival outcome. Ectopic miR-5195-3p expression curtailed proliferation, migration, and invasion of SW1116 and HT29 cells. Additionally, we discovered that miR-5195-3p directly targets and negatively influences Toll-like receptor 4 (TLR4) in CRC cells. Moreover, an inverse relationship was noted between miR-5195-3p and TLR4 expression in CRC tissue samples. Notably, restoring TLR4 expression counteracted miR-5195-3p's suppressive impact on cell growth, motility, invasiveness, epithelial-mesenchymal transition (EMT), and the TLR4/MyD88 signaling pathway in SW1116 and HT29 cells.

CONCLUSIONS

MiR-5195-3p suppresses the CRC cellular functions through the downregulation of TLR4/MyD88 signaling, indicating that targeting miR-5195-3p might offer a viable therapeutic strategy for CRC.

Insights Into Colorectal Carcinoma: A Comprehensive Review of MicroRNA Expression Patterns

Colorectal carcinoma (CRC) remains a significant contributor to cancer-related morbidity and mortality worldwide. MicroRNAs (miRNAs) have emerged as crucial regulators of gene expression and play critical roles in various biological processes, including carcinogenesis. This comprehensive review aims to elucidate the role of miRNAs in CRC by analyzing their expression patterns and functional implications. An extensive literature review identified dysregulated miRNAs associated with different stages of CRC progression, from initiation to metastasis. These miRNAs modulate key signaling pathways in tumor growth, invasion, and metastasis. Furthermore, we discuss the potential of miRNAs as diagnostic biomarkers and therapeutic targets in CRC management. Future research directions include elucidating the functional significance of dysregulated miRNAs using advanced experimental models and computational approaches and exploring the therapeutic potential of miRNA-based interventions in personalized treatment strategies for CRC patients. Collaboration among researchers, clinicians, and industry partners will be essential to translate these findings into clinically impactful interventions that improve patient outcomes in CRC.

Unraveling the Multifaceted Role of the miR-17-92 Cluster in Colorectal Cancer: From Mechanisms to Biomarker Potential

Colorectal cancer (CRC) is a complex disease driven by intricate mechanisms, making it challenging to understand and manage. The miR-17-92 cluster has gained significant attention in CRC research due to its diverse functions and crucial role in various aspects of the disease. This cluster, consisting of multiple individual miRNAs, influences critical processes like tumor initiation, angiogenesis, metastasis, and the epithelial-mesenchymal transition (EMT). Beyond its roles in tumorigenesis and progression, miR-17-92's dysregulation in CRC has substantial implications for diagnosis, prognosis, and treatment, including chemotherapy responsiveness. It also shows promise as a diagnostic and prognostic biomarker, offering insights into treatment responses and disease progression. This review provides a comprehensive overview of recent advancements and the context-dependent role of the miR-17-92 cluster in colorectal cancer, drawing from the latest high-quality published data. It summarizes the established mechanisms governing miR-17-92 expression and the molecular pathways under its influence. Furthermore, it examines instances where it functions as an oncogene or a tumor suppressor, elucidating how cellular contexts dictate its biological effects. Ultimately, miR-17-92 holds promise as a biomarker for prognosis and therapy response, as well as a potential target for cancer prevention and therapeutic interventions. In essence, this review underscores the multifaceted nature of miR-17-92 in CRC research, offering promising avenues for enhancing the management of CRC patients.

Implications in Cancer of Nuclear Micro RNAs, Long Non-Coding RNAs, and Circular RNAs Bound by PRC2 and FUS

The eukaryotic genome is mainly transcribed into non-coding RNAs (ncRNAs), including different RNA biotypes, such as micro RNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), among others. Although miRNAs are assumed to act primarily in the cytosol, mature miRNAs have been reported and functionally characterized in the nuclei of different cells. Further, lncRNAs are important regulators of different biological processes in the cell nucleus as part of different ribonucleoprotein complexes. CircRNAs constitute a relatively less-characterized RNA biotype that has a circular structure as result of a back-splicing process. However, circRNAs have recently attracted attention in different scientific fields due to their involvement in various biological processes and pathologies. In this review, we will summarize recent studies that link to cancer miRNAs that have been functionally characterized in the cell nucleus, as well as lncRNAs and circRNAs that are bound by core components of the polycomb repressive complex 2 (PRC2) or the protein fused in sarcoma (FUS), highlighting mechanistic aspects and their diagnostic and therapeutic potential.