IL2 and retinoblastoma: TILT-123 is an oncolytic adenovirus that incorporates transgenes for human tumor necrosis factor alpha (TNF-α) and interleukin-2 (IL-2) in addition to Ad5/Ad3 chimeric fiber designed to optimize transduction efficiency, and a 24 base pair deletion in E1A to confer selective replication in cells lacking a normal retinoblastoma/p16 pathway [82].