CXADR and cancer: The identification of CAR as the primary adenovirus receptor triggered numerous studies demonstrating that primary cancer cells are frequently refractory to adenoviral infection because of a paucity of CAR on the cell surface (Dmitriev et al, 1998; Hemmi et al, 1998; Miller et al, 1998; Blackwell et al, 1999; Li et al, 1999; Vanderkwaak et al, 1999).