Tumor exosomes: cellular postmen of cancer diagnosis and personalized therapy.

Nanosized (30-150 nm) extracellular vesicles 'exosomes' are secreted by cells for intercellular communication during normal and pathological conditions. Exosomes carry biomacromolecules from cell-of-origin and, therefore, represent molecular bioprint of the cell. Tumor-derived exosomes or TDEx modulate tumor microenvironment by transfer of macromolecules locally as well as at distant metastatic sites. Due to their biological stability, TDEx are rich source of biomarkers in cancer patients. TDEx focused cancer diagnosis allows liquid biopsy-based tumor typing and may facilitate therapy response monitoring by developing novel exosomes diagnostics. Therefore, efficient and specific capturing of exosomes for subsequent amplification of the biomessages; for example, DNA, RNA, miRNA can reinvent cancer diagnosis. Here, in this review, we discuss advancements in exosomes isolation strategies, presence of exosomes biomarkers and importance of TDEx in gauging tumor heterogeneity for their potential use in cancer diagnosis, therapy.