Among these potentially novel ER-related miRNAs, four miRNAs (hsa-miR-26a, hsa-miR-92b, hsa-miR-191, hsa-miR-492) appear to show consistently higher expression across all the ER-positive cell lines (fold change ≥ 1.5), and as yet only hsa-miR-26a has been implicated in breast carcinogenesis whereas hsa-miR-26a and hsa-miR-92b have also been implicated in brain tumors [39,40]. This evidence concerns the gene ESR1 and brain neoplasm.