MicroRNAs expression in semen and testis of azoospermic men

MicroRNAs (miRNAs) are involved in the regulation of spermatogenesis, are detected in semen and may be useful as molecular markers for predicting residual complete spermatogenesis in azoospermic men. This study aims to demonstrate the biomarker potential of miRNAs that are detected in semen and testicular tissue. The study results showed that the sequenced miRNA profiles of SUP fraction samples were distinct from the other fractions. The expression of miR‐202‐3p was significantly lower in the azoospermic compared with the normozoospermic specimens, and a trend was observed for miR‐629‐5p. Differences in expression levels in the SUP were observed among the various pathologies, but not to a level of significance, possibly due to the small subgroups. MiRNA‐370‐3p was significantly higher in SUP samples from azoospermic men without sperm cells in testis (p = 0.05). In testes, the three miRNAs were expressed at higher levels in the obstructive and spermatocyte maturation arrest pathologies than in mixed atrophy and Sertoli only. miR‐202‐3p was detected in all testicular samples. Based on study results, it was concluded that miRNA expression profiles in semen were distinguishable between azoospermic and normozoospermic men. The miRNA profile also diverged among azoospermic men subdivided according to their testicular pathologies. The levels of specific miRNAs in the testis and in the SUP were not directly correlated.