To evaluate whether BRCA1-IRIS overexpression is indeed required for TNBC tumor formation and/or maintenance, MDA-MB-231 or MDA-MB-468 (2 x 106) cells expressing shcontrol or shIRIS were injected in mammary fat pads (second left and fourth right) of 6- to 8-week-old female SCID mice (mice, n = 6/cell line → tumors, n = 12/cell line). The gene discussed is BRCA1; the disease is neoplasm.