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Ribonucleic acid or RNA is a nucleic acid present in all living cells. It plays an important role in various cellular processes such as decoding genetic information from DNA for protein synthesis, regulating gene expression, and assisting with protein synthesis. Besides these cellular functions, Ribonucleic Acid (RNA) Markers also serves as biomarkers for disease diagnosis and prognosis.
Types of RNA biomarkers
Several types of RNA can serve as potential biomarkers:
Messenger RNA (mRNA) – mRNA carries genetic instructions from DNA to the ribosomes for protein production. Changes in mRNA expression levels can reflect disease states and responses to treatments. Measuring mRNA levels has been useful for cancer diagnosis and prognosis. For example, mutations or downregulation of tumor suppressor genes like BRCA1 lead to increased breast cancer risk by affecting pathways related to DNA repair.
Non-coding RNA (ncRNA) – ncRNAs like microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs) do not code for proteins but regulate gene expression. Aberrant expression of ncRNAs has been linked to various diseases. Circulating ncRNAs detected in body fluids like blood can serve as minimally invasive biomarkers for non-invasive monitoring of disease progression or treatment response.
Cell-free RNA – RNA fragments released from dying cells into the bloodstream provide a “liquid biopsy” method for tracking tumor changes. Analysis of mutations, methylation levels, and expression patterns in cell-free RNA has applications in cancer diagnosis, prognosis, and monitoring recurrence.
Applications of RNA biomarkers
Some key applications of RNA biomarkers include:
Cancer diagnosis and prognosis – Expression profiles of mRNA and ncRNAs can characterize cancer types and stages. They also predict treatment response and patient outcomes better than routine clinical parameters alone. For example, a panel of miRNAs help classify hard-to-diagnose cancers and distinguish between indolent and aggressive prostate cancers.
Neurological disorders – Changes in circulating ncRNAs associated with neurological disorders like Alzheimer’s, Parkinson’s, stroke, and traumatic brain injury provide insights into disease mechanisms and potential liquid biopsy tests. miRNAs show diagnostic value for distinguishing between Alzheimer’s and other dementias.
Infectious diseases – Host and microbial RNA signatures detected during viral or bacterial infections reveal details about pathogenesis, transmission, clinical course, and treatment monitoring that enables timely clinical decisions. For example, SARS-CoV-2 RNA levels measured by PCR strongly correlate with COVID-19 severity and recovery.
Technological advances driving RNA biomarkers
Next-generation sequencing (NGS) technologies have transformed the analysis of RNA biomarkers:
RNA sequencing (RNA-seq) globally profiles transcriptomes to discover RNA biomarkers with high diagnostic or prognostic value. Compared to microarrays, RNA-seq delivers more precise and comprehensive information.
Single-cell RNA sequencing (scRNA-seq) examines transcriptional profiles of individual cells, revealing insights into cellular dynamics during development and disease. It is invaluable for cancer research by identifying rare tumor subpopulations driving metastasis.
Targeted panels screen predefined sets of clinically important RNAs like miRNAs in large patient cohorts to validate biomarker candidates. This approach is suitable for clinical applications.
Digital PCR detects RNA mutations with high specificity and sensitivity. Its applications include noninvasive detection of rare cancer mutations in liquid biopsies.
These high-throughput techniques are ushering in an era of precision oncology using RNA biomarkers to predict responders, monitor treatment effectiveness, and detect recurrence early.
Challenges and future directions
While RNA biomarkers show immense clinical potential, some key challenges remain:
Standardization of protocols for consistent and reproducible measurements across laboratories is crucial before clinical adoption.
Large, well-designed validation studies are still needed to confirm RNA signatures and build robust prediction models.
Technical limitations in analyzing RNAs that are degraded, low in abundance, or lack standardized detection methods need addressing.
Integrating multi-omics data from genomics, epigenomics, proteomics, and metabolomics with transcriptomics could yield more comprehensive insights.
Commercialization through partnerships between academia and industry will be important to translate research into clinically approved tests and products.
Addressing these challenges through multidisciplinary collaborations promises to fully realize the potential of Ribonucleic Acid (RNA) Markers biomarkers for precision medicine and personalized healthcare in the future. Continued technological advances and big data approaches will be pivotal in unlocking their clinical utility.
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1. Source: Coherent Market Insights, Public sources, Desk research
2. We have leveraged AI tools to mine information and compile it
