A NE of Ricinus communis EO showing droplets of 81.4 nm and exhibiting superb antioxidant activity considerably reduced the viability of HepG2 cells after incubation for 48 h, and with increasing NE doses, an upregulation of the expression of caspase-3 and an increase in sub-G1 peaks in treated cancer cells were observed. The gene discussed is CASP3; the disease is cancer.