Abstract

MicroRNAs (miRNAs) represent a large family of small, nearly 20-22 nucleotide non-coding RNAs that modulate the expression of target genes, specially at the post-transcriptional level. Many studies suggest that miRNAs play a role in homeostatic preservation and that deviant expression of miRNAs is usually seen in several types of diseases, such as cancer. Exosomes are extracellular vesicles synthesized in the cells. They induce cell-cell communication and immunoregulatory functions. In cancer, exosome secretion is associated with primary tumor growth, regulation of local tumor microenvironment, and stimulation of distant metastatic niche formation during tumor spread. MiRNA expression is often dysregulated in tumour cells and can be reflected by distinct exosomal miRNA (ex-miRNA) profiles isolated from the cancer patients. In this minireview, we sum up the current understanding about exosomal miRNAs (ex-miRNAs) functions in cancer. We also review the possible clinical utilization of ex-miRNAs in cancer, for instance as diagnostic marker and therapeutic target.

Keywords

microrna, exosomes, cancer, marker, plasma, serum, urine, reticulocytes, tumor progression, freeze-thaw