CYP27A1 and neoplasm: Genetic fusion of TPP11 to the C-terminus of the heavy chain of an anti-EGFR antibody (designated as cetuximab-TPP11: Ctx-TPP11) improved tumor homing and tumor tissue penetration of Ctx-TPP11 by loosening cell–cell junctions, as compared to the parental antibody, cetuximab [20,21].