Cancer Therapy with Metronomically Scheduled Cyclophosphamide: Experimental Modalities within GDEPT and Tumor Escape Mechanisms
CPA is an anticancer drug that can be applied in conventional tumor therapy, in combination with gene transfer and in antiangiogenic approaches with low dose metronomically scheduled regimes. In the context of metronomic CPA therapy, acrolein was shown to exhibit antiangiogenic effects and therapeutic contribution has to be reconsidered. Despite improved treatment regimes, drug resistance will be still an obstacle in chemotherapeutic regimes due to different escape mechanisms; progress in the development of new strategies might be achieved by suitable in vitro models such as the agarose overlay system or agarose wrapped microspheroids.