Our findings indicate that elevated levels of intracellular Par-4 can sensitize MCF-7 cells to apoptosis and growth inhibition by docetaxel, which is a fundamental and effective chemotherapeutic agent against primary and advanced breast cancer, suggesting that intracellular Par-4 are involved in the pro-apoptotic and growth inhibitory action of docetaxel in breast cancer cells. The gene discussed is PAWR; the disease is breast cancer.