ENPP4 and colorectal carcinoma: In the late-stage CRC cells, receptor GRID2 binds with the ligand CBLN1 (protein secretion) and sequentially transmits the signal to TF WD repeat domain 4 (WDR4) through proteins cell cycle associated protein 1 (CAPRIN1), secreted protein acidic and cysteine rich (SPARC), protein phosphatase 2 regulatory subunit B’’beta (PPP2R3B), ectonucleotide pyrophosphatase/phosphodiesterase 4 (ENPP4), and single-pass membrane protein with aspartate rich tail 1 (SMDT1).