pubs.acs.org
microRNA-Based Liquid Biopsies for Breast Cancer: Advances in Detection and Management Using Electrochemical Biosensors
Breast cancer (BC) remains the leading cause of cancer-related mortality in women, highlighting the need for accessible and frequent screening tools that extend beyond centralized imaging and tissue biopsy. Liquid biopsy has emerged as a promising approach due to the presence of circulating biomarkers in easily accessible body fluids such as blood, saliva, and urine. Among these, microRNAs (miRNAs) are particularly attractive biomarkers owing to their stability and strong associations with BC initiation, progression, and treatment response. However, the clinical translation of miRNAs for routine and frequent BC screening is currently constrained by laboratory-based analytical methods that require complex workflows, specialized instrumentation, and skilled personnel. Electrochemical nucleic acid biosensors (ENABs) offer a compelling alternative by combining high analytical sensitivity, low cost, and rapid assay times with inherent compatibility for miniaturized, portable, and point-of-care operation. These attributes position ENABs as well-suited platforms for decentralized and repeat testing, enabling more accessible and frequent BC screening using liquid biopsy samples. In this review, we summarize key BC-associated miRNAs across relevant liquid biopsy matrices and critically assess recent advances in ENAB technologies, including signal amplification strategies and nanomaterial-enabled interfaces for detecting low-abundance miRNAs. Finally, we discuss the technological, analytical, and clinical challenges that must be addressed to facilitate the adoption of electrochemical miRNA biosensors as complementary tools for BC screening, monitoring, and diagnosis.