Profiles of urinal exosomal miRNAs derived from bladder cancer.

Introduction: Exosomes contain nucleic acids and proteins inside of them. These are suggested as cell-cell communication materials and it is considered that they can modulate the status of other cells.

Material and methods: To understand the bladder cancer (BC) related exosomal microRNAs (miRNAs), we compared the 752 urine exosomal miRNAs in healthy control (n = 7), low grade (LG) BC (n = 6) and high grade (HG) BC (n = 6) by RT-qPCR.

Results: The differential expressing (DE) urine exosomal miRNAs (2 > fold regulation) were 96 and 78 in LG and HG, respectively. Our exosomal miRNAs profiles cover many miRNAs which have been reported in BC patients' tissues and other biofluids. Most DE exosomal miRNAs were up-regulated in the profiles. Seven up-regulated exosomal miRNAs in the LG group (miR-28-5p, miR-16-5p, miR-28-3p, miR-24-3p, miR-25-3p, miR-19b-3p and miR10b-5p) and 3 miRNAs in the HG group (miR-150-5p, miR-28-5p and miR28-3p) were found as directly TP53 targeting. Twenty-two and 18 PTEN targeting miRNAs were observed in up-regulated miRNAs of LG and HG. The target genes of these exosomal miRNAs and their interaction network predicted that the TP53 is the strongest hub gene in both BC groups exosomal miRNA networks. Several DE miRNAs were found that could potentially be used as biomarkers for the diagnosis of BC.

Conclusions: Profiles of urinal exosomal miRNAs derived from BC manifested potentially epigenetic regulation of the TP53 and PTEN genes as compared to other oncogenes and tumour suppressors.