CD47 and colorectal cancer: Investigating on possible interacting proteins from STRING (Figure 2), CD47 interacts with other clusters of differentiation proteins, and also with a tyrosine kinase (PTK2), a cytoplasmic protein that is known to be cleaved by caspase 3 during cell death [66], interrupting survival signals from the extracellular matrix, and a G-protein coupled receptor (FPR2) that is reported to have an anti-apoptotic function in colorectal cancer [67].