Beck Samuel¹, Lehmann Sophie², Clarke Henry³, Berger Laura⁴, Wolf Felix⁵, Adams Lily⁶
ABSTRACT:
Exosomes are small extracellular vesicles (30–150 nm) secreted by all cell types, including tumor cells, and contain bioactive molecules such as nucleic acids, proteins, and lipids. These vesicles play a crucial role in intercellular communication by transferring their cargo to neighboring or distant cells, influencing various biological processes including tumor growth, metastasis, and immune evasion. In the context of cancer, tumor-derived exosomes facilitate angiogenesis, pre-metastatic niche formation, and therapeutic resistance. Due to their stability in bodily fluids like blood, urine, and saliva, exosomes have emerged as promising candidates for «liquid biopsy» applications, offering a non-invasive method for early cancer detection, monitoring disease progression, and assessing treatment responses. Exosomal cargo, including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), proteins, and metabolites, provides valuable molecular signatures that can be exploited for cancer diagnostics and prognostics. This review highlights the biological roles of exosomes in cancer, discusses their diagnostic and prognostic applications, and explores their potential for personalized therapy. Furthermore, we address the challenges of exosome isolation, standardization, and clinical validation, and outline the future directions of exosome-based diagnostics in oncology.