The increase of apoptosis and the decrease of proliferation by angiogenesis inhibitor in rat mammary tumors

We have investigated the change of balance between proliferating and apoptotic tumor cells in dimethylebenz(a)-anthracene (DMBA)-induced rat mammary tumors by using anti-angiogenic drug, AGM-1470 and anticancer drug, 5'-deoxy-5-fluorouridine (5'-DFUR). The rate of PCNA positive proliferating cells was decreased in the tretment groups, especially in AGM-1470 and in the combination of AGM-1470 and 5'-DFUR. And apoptotic index evaluated by TUNEL method was increased in 5'-DFUR and in the combination group. The ratio of proliferating cells/apoptotic cells was markedly decreased in AGM-1470 and AGM+5'-DFUR group compared to control group. These data suggested that anti-angiogenic drugs might regulate the growth behavior of tumor cells by changing the microenvironments.