For example, siRNA can be efficiently delivered into cancer cells and specifically inhibit the expression of anti-apoptosis genes, such as Bcl-2, Bcl-xl, XIAP (Kunze et al., 2012), as well as the genes encoding endothelial growth factor receptors (VEGFR 2 and EGFR), triggering the cell apoptosis and simultaneously improving the sensitivity of cancer cells to chemotherapeutic drugs. The gene discussed is BCL2L1; the disease is cancer.