Expression assays in clinical samples from a variety of tumor types have indicated down-regulation of Shh-targeting miRNAs such as miR-26a [20] and miR-1471 [21] in breast cancer, miR-129-5p in cervical cancer [28], miR-361-3p in retinoblastoma, miR-26b-5p in gallbladder carcinoma [33], and miR-361-3p in retinoblastoma [53]. This evidence concerns the gene SHH and retinoblastoma.