Untersuchungen zur Expression der microRNA-Gen-Cluster C19MC und miR-371-3 in Normalgeweben und Tumoren

The miRNA gene clusters C19MC and miR-371-3 are deregulated in a number of tumour entities. In this thesis the expression and regulation of the clusters was examined in thyroid carcinomas, testicular germ cell tumours and placenta. It was demonstrated that both clusters are not activated in thyroid carcinomas and that in testicular carcinomas, C19MC is significantly higher expressed in non-seminomas and tumours in advanced clinical stages. Moreover, C19MC has potential as serum tumour marker for testicular cancer. It was shown that placental mesenchymal stromal cells (MSCs) and chorioamniotic membrane highly express C19MC. Since placental and chorioamniotic mesenchymal stromal are immunosuppressive C19MC miRNAs might play a role in inducing maternal immune tolerance against the placenta and fetus. In case of an immunosuppressive function of C19MC its miRNAs might be applied to treat autoimmune diseases or to suppress the immune response against allogeneic tissue transplants.