microRNA profiles of serum exosomes in healthy controls and colorectal cancer patients-1

MicroRNAs (miRNAs) are intrinsic regulators in the various cellular processes, and their abnormalities are considered to be involved in the onset of human disorders, including cancer. Circulating miRNA is focused as new cancer biomarker however it is regarded that circulating RNA are released not only from tumor but also by various pathways. Recently, exosomes, small membrane vesicles, have been a major interest in cancer research field, because of their unique biological properties. Exosomes are secreted from various cells and the components (Lipids, mRNAs, miRNAs and proteins) reflect origin of the cells secreting them. Identification of exosomal miRNAs from cancer cells is expected to provide useful biomarkers of cancer. To identify specific exosomal miRNAs as candidate biomarkers for colorectal cancer, we profiled exosomal miRNAs in sera of colon cancer patients (n=88) at various TNM stages (I to IV) and healthy controls (n=11) and selected significantly higher microRNAs in serum exosomes of colorectal cancer patients than that of healthy controls. Moreover, we tried to detect their serum exosome levels of using samples from patients after surgical resection of primary tumors (n=24).