Expression of miR-302a, miR-302b, miR-302c, miR-302d, miR-367, miR-371, miR-372, miR-373, miR-10b, miR-21 and miR-93 in cells of different histotypes of testicular germ cell tumors

Introduction. Testicular germ cell tumor is a relatively rare disease. Its high social significance is due to the fact that this pathology occurs in young patients. The standard schemes of polychemotherapy determine the potential possibility of effective treatment for most of the patients even with an advanced disease. Several circulating markers (alpha-fetoprotein, human chorionic gonadotropin and lactate dehydrogenase) are being used for therapy monitoring, but the low diagnostic specificity of these molecules determines the need to develop new approaches. Over the past years, circulating microRNA, for instance miR-371a-3p, appeared to be promising marker for testicular germ cell tumor monitoring. However, to develop and to implement in practice the microRNA-based diagnostic technologies, it’s necessarily to understand the features of the microRNA expression alterations specific for different histological types of testicular germ cell tumor.The study objective – to evaluate changes in the expression of several potential marker microRNA molecules (miR-302/ miR-367, miR-371/miR-373) in testicular germ cell tumor samples of various histological types.Materials and methods. Testicular germ cell tumor samples (n = 61), including seminomas, embryonic carcinomas, post-pubertal teratomas, yolk sac tumors, chorioncarcinomas, and corresponding normal tissue samples (n = 61) were included in the study. The analysis of selected miRNA expression was performed by reverse transcription and polymerase chain reaction.Results. We identified the changes in the expression profile of the miR-302/miR-367 cluster typical for semines, embryonic carcinomas, post-pubertal teratomas, yolk sac tumors and chorioncarcinomas, as well as changes in the expression profile of the miR-371/miR-373 cluster, universal for all histotypes except chorioncarcinomas. Inhibition of miR-10b and miR-145 expression in semines, embryonic carcinomas, and post-pubertal teratomas was demonstrated.Conclusion. Activation of miR-302b, miR-302d, miR-371a expression and inhibition of miR-10b, miR-145 expression in the tissue of the most common variants of testicular germ cell tumor is a characteristic feature of these tumors. The detected changes are significant and can lead to corresponding changes in the profile of circulating microRNAs.