This has been supported experimentally by a study by Liang et al. [56], who showed that BoM-1833 cells, a human breast cancer cell line which metastasizes specifically to the bone in nude mice, show higher osteolytic rates compared with estrogen receptor positive (ER+) MCF7 and the TNBC cell line MDA-MB-231. This evidence concerns the gene ESR1 and breast cancer.