Exosomal proteins as a new approach in cancer diagnosis

The term personalized medicine has gained widespread acceptance in field of oncology, where it most often refers to a vision of cancer treatment which is tailored to individual patients based on the molecular profile of their tumour. In addition, scientists are developing and using diagnostic tests based on genetics or other molecular mechanisms to better predict patients’ responses to targeted therapy. Exosomes are small sized (30–120 nm) extracellular vesicles with endosomal origin that throw directly from the budding of the plasma membrane. Exosomes play and crucial role in cell-to-cell communication by carrying their contents, including proteins, metabolites, RNAs, DNAs and lipids. While exosomes are secreted by multiple cell types, cancer derived exosomes not only influence the invasive potentials of proximally located cells, but also affect distantly located tissues.The retrieved studies were searched through the PubMed, Google Scholar, Scopus, databases. Different studies have been demonstrated that, cancer derived exosomes likely serves as biomarker for early detection of cancer as they carry the cargo reflective of genetic or signaling alterations in cancer cells of origin. Exosome purity is assessed by measuring exosome-specific marker antigen or protein using ELISA assay, nanoparticle tracking analysis (NTA), and flow cytometry (FACS).Exosomes contain a variety of proteins that reflect their origin and alteration of the parental cells. Exosome-based diagnostics provide higher sensitivity and specificity over conventional biopsy or liquid biopsy biomarkers due to their stability in biofluids. Furthermore it provides the convenient and non-invasive way of diagnosis over tissue biopsy that requires surgery. Some proteins serve as exosomal cancer markers for instance: CD63 (in melanoma), CD24 and EpCAM (in breast cancer) etc.

Keywords:

Exosome , diagnostic marker , cancer