using primary cholangiocarcinoma cells, cyclophilin A (CyPA), a ligand to CD147 was shown to bind on CD147 and stimulate extracellular receptor kinase 1/2 (ERK1/2) phosphorylation followed by upregulation and phosphorylation of cyclin D1 and retinoblastoma protein (RB), leading to G1/S transitioning thus the propagation of cell cycle (54). Here, PPIA is linked to cholangiocarcinoma.