MiR-15a, miR-16-1 and miR-17-92 cluster expression are linked to poor prognosis in multiple myeloma.

Multiple myeloma (MM) is characterized by a profound genomic instability of potential prognostic relevance. Loss of chromosome 13, observed in almost half of patients, negatively affects prognosis. MiR-15a, miR16-1 and miR-17-92 cluster, located on 13q, play important roles in the regulation of cell proliferation, differentiation and apoptosis. Therefore, we investigated a possible correlation of miRNA expression with chromosome 13 deletions (del(13)) and prognosis. We measured the expression of miR-15a, miR16-1 in 70 newly diagnosed MM patients and miR-17-92 cluster in 85 newly diagnosed MM patients by quantitative real-time PCR analyses. MiR-15a, miR-16-1 and miR-17-92 cluster expression levels are independent of the del(13). High levels of miR-15a, miR-16-1, miR-17, miR-20a and miR-92-1 are associated with shorter progression-free survival (PFS), suggesting poor prognosis. Our data suggest that the expression of specific miRNAs may be contributing to MM prognosis.