In the field of adenoviruses, the inoculation of an E1B-55-kDa-deleted oncolytic adenovirus (ZD55) armed with a soluble form of VEGFR1 led to a marked reduction in colon tumor growth with a decreased microvessel density and increased tumor apoptosis [149], whereas similar adenovirus vectors provoked enhanced anti-angiogenic and anti-tumor effects in colon and prostate xenografts murine models [150], with reduced vessel densities and increased apoptosis in both endothelial and tumor cells [152]. This evidence concerns the gene FLT1 and neoplasm.