Captopril augments antitumor activity of cyclophosphamide in mice.

Patients suffering from cancer (responsive to chemotherapy) are usually treated with a combination of anticancer drugs. In our previous studies, we found that captopril exerted antitumor action on Lewis lung carcinoma (LLC) in mice. This prompted us to evaluate the antitumor effect of captopril combined with cyclophosphamide. BD1F1 mice with LLC received two injections of captopril (5 mg/mouse) at a 1 h interval. Two hours later they were injected with cyclophosphamide (6 mg/mouse). Captopril pretreatment augmented the antitumor action of cyclophosphamide expressed as the survival time and the number of cured mice. Captopril given for five days before cyclophosphamide treatment did not change the antitumor activity of cyclophosphamide.