There is thought to be mechanistic synergy between the 2 drug classes: VEGF promotes cancer immune evasion through a variety of mechanisms, and inhibition of VEGFR can normalize abnormal tumor vasculature, allowing for increased infiltration of immune effector cells into tumors and the resultant conversion of the tumor microenvironment from an immunosuppressive to an immunosupportive one.44 Here, KDR is linked to neoplasm.