磷酸氯喹抑制劑Chloroquine diphosphate, used as an antimalarial drug, can increase the susceptibility of cancer cells to chemotherapy and radiation via inducing autophagy. According to reports, Chloroquine diphosphate is an adjuvant for chemotherapy and radiation for inducing cell autophagy to anti-Y cells metastasis or growth. Chloroquine diphosphate induces cells autophagy by arresting cells in G1 and up-regulating the expression of p27/p53 while down-regulates the expression of CDK2 and cyclin D1. CNE-2 human nasopharyngeal carcinoma cells, pretreated with chloroquine diphosphate, enhanced ionizing radiation-induced cell apoptosis via increasing the ratio of cells autophagic. When treated with mouse breast Y 4T1 cells, chloroquine diphosphate induced cells apoptosis by inhibiting cellular proliferation and viability in a time- and dose-dependent manner. In human colon Y DLD-1 cells, the combination of chloroquine diphosphate and 5-FU could induce autophagy to inhibit cells multiplication.