Tang et al. observed that HAp, via the activation of caspase-3 and -9 (but not caspase-8), inhibits cell proliferation and induces apoptosis in different cancer cells (gastric cancer cells [MGC80-3], cervical adenocarcinoma epithelial cells [HeLa], and hepatoma cells [HepG2]) [100]. The gene discussed is CASP3; the disease is cancer.