Consistent with these preliminary in silico findings, miRNA profiling of a series of patient-derived specimens (n = 4 normal, n = 97 MM, n = 30 PCL cases) confirmed a significant inverse correlation between miR-22 and LIG3 expression in PCL cases and downregulation of miR-22 during disease progression and in relapsed patients (Fig. 3b, Supplementary 3b). This evidence concerns the gene LIG3 and plasma cell leukemia.