In addition to the early reports of miRNA profiling in cancer, mouse models have demonstrated that monoallelic Dicer1 loss facilitates Kras-driven lung tumor formation and tumor formation in a retinoblastoma-sensitized background, whereas biallelic Dicer1 loss drives angiosarcoma, suggesting a tumor-suppressive role of Dicer1(45), (46), (47). Here, DICER1 is linked to retinoblastoma.