A new approach to cancer chemotherapy: selective enhancement of tumor blood flow with angiotensin II.

Elevation of the mean arterial blood pressure to approximately 150 mmHg by infusion of angiotensin II resulted in an approximate 5.7-fold selective increase in blood flow in tumor tissue without increasing blood flow in normal tissue. This finding of no autoregulation of blood flow in tumor tissue was made in an experiment on inbred DONRYU rats with sc transplanted AH109A solid tumors (Yoshida ascites hepatoma). Changes in tissue blood flow were measured by a thermoelectrical method. In another experiment in which DONRYU rats with sc transplanted AH272 solid tumors were used, the chemotherapeutic effect of mitomycin C on main tumors and lymph node metastatic foci was markedly enhanced in rats with angiotensin-induced hypertension, as compared to its effect in rats without angiotensin-induced hypertension. Thus a new approach to cancer chemotherapy has been demonstrated in which the delivery to tumor tissue of systemically administered anticancer drugs can be selectively enhanced.