From Fluids to Forecasts: The Promise of Small Extracellular Vesicle miRNAs in Revolutionising Cancer Diagnostics

Abstract

Small extracellular vesicle (sEV) RNAs, particularly microRNAs (miRNAs), have emerged as pivotal biomarkers for cancer diagnosis and prognosis. Encapsulated within sEVs, these miRNAs reflect specific cellular characteristics and disease states, offering a window into cancers’ molecular underpinnings. Notably, miRNAs, such as miR-7977, miR-98-3p, miR-620, and miR-17-5p in lung cancer and miR-373, miR-1246, miR-223-3p, and miR-21 in breast cancer, have been identified in sEVs extracted from various bodily fluids, including blood, urine, and saliva. Their remarkable stability and ease of isolation make them prime targets for non-invasive cancer detection strategies. The fold change of these miRNAs is intricately linked with cancer progression, metastasis, and therapeutic responses, underscoring their potential as diagnostic and prognostic markers. Traditional detection methods like quantitative reverse transcription-polymerase chain reaction (qRT-PCR) have been foundational; however, recent biosensing technologies, such as nanopore sequencing and microfluidic chips, offer enhanced sensitivity and specificity for detecting miRNAs in clinical samples. These innovative approaches refine the detection process and pave the way for real-time monitoring of disease progression and treatment efficacy. Overall, the collective evidence positions sEV miRNAs as robust indicators for cancer, signalling a shift towards personalised cancer care that emphasises early detection and tailored treatment strategies.