Exosomes: New Biomarkers for Targeted Cancer Therapy

Exosomes have emerged as novel and important mediators of intercellular communication. They contain bioactive molecules including proteins, DNA, mRNA and miRNA, which are transferred from donor to target cells, leading to exchanges of genetic information and reprogramming of the recipients. Recently, it has been suggested that tumor cells release increased amounts of exosomes which are involved in tumor initiation, growth, progression, metastasis, and multidrug resistance. Exosomal shuttling between cells contributes to transfer material from tumor to immune and stromal cells, favoring the escape from immune surveillance and the formation of a conditioned tumor niche. The critical involvement of exosomes in cancer has evidenced important roles both for diagnostic and therapeutic purposes. Exosomes can be exploited as biomarkers for diagnosis and as targets for therapy. They can be considered potential therapeutic agents. Due to their high loading efficiency and biocompatibility they can be used as vehicles for delivering targeted anti-cancer drugs with low immunogenicity and toxicity.