The most common mechanism through which NPs inhibit the proliferationof cancer cells is through the induction of apoptosis.10,99−103 This current study then explored if the exposure of three functionalizedAuNPs induced apoptosis by analyzing the mitochondrial expressionof PARP, caspase-3, and caspase-9 using Western blotting. The gene discussed is CASP9; the disease is cancer.