Askarian-Amiri et al. found that ZFAS1 is highly expressed in normal breast tissue and down-regulated in breast cancer tissue, and the knockdown of ZFAS1 in an epithelial cell line of breast cancer promoted cell proliferation, which suggested that ZFAS1 might be a tumor suppressor gene in breast cancer [9]. The gene discussed is ZFAS1; the disease is breast carcinoma.