BIRC5 and retinoblastoma: Survivin (Sur), as an example of IAPs, which is highly overexpressed in the nucleus, cytoplasm, and cellular organelles such as the mitochondria of various cancer types including retinoblastoma (RB), is responsible for mediating various oncogenic signaling pathways, inhibition of apoptosis, rapid cell growth, and eventually as the name indicates the survival of tumor cells [75–78].