Since the function of ERβ encoded by the ESR2 gene in BC has, for a long time, not been convincingly described due to inconsistent studies mainly based on the use of unspecific antibodies, few studies have been performed validating the ESR2 gene as an miRNA target, e.g., of miR-92 or miR-30a [104,150], although databases such as TargetScan [151] or miRTarBase [152] predict it to be targeted by a variety of miRNAs. The gene discussed is ESR2; the disease is breast cancer.