KDR and neoplasm: The present studies were designed to address several questions raised by our prior finding that VEGF-directed RTKIs can block metro-CPA-induced innate immune responses [10], namely, whether the observed immune inhibition was: (a) due to the loss of tumor vascularity and hence a route to traffic immune cells into the tumor; (b) a result of off-target effects of the RTKIs (i.e., inhibition of kinases other than VEGFRs); or (c) a consequence of VEGFR inhibition unrelated to anti-angiogenesis.