In the present study, we show that withanolides inhibited the constitutive activation of NF-κB in MDA-MB-231, an ER-negative human breast cancer cell line, and reduced the anti-apoptotic proteins (Bcl-2, Bcl-xL, and c-FLIP) which are regulated by NF-κB. The gene discussed is NFKB1; the disease is breast cancer.