In our previous study, we reported that the knockdown of LSD1 in breast cancer cells resulted in the downregulation of miR-6881-3p in exosomes, which inhibited the differentiation of osteoblasts and promoted osteoclasts through modulation of the expression of the target genes pre-B-cell leukemia transcription factor 1 (PBX1) and additional sex combs-like 2 (ASXL2) respectively [22]. The gene discussed is KDM1A; the disease is breast cancer.