Several covariate mechanisms are responsible for multi-drug resistance in breast cancer cells including increased drug efflux (P-glycoprotein-P-gp), CSCs (CD24), drug detoxification (glutathione S-transferase) deregulated apoptosis (Bcl-2 overexpression) and overexpression of cytokines (SCF)[8]. The gene discussed is ABCB1; the disease is breast carcinoma.