PPIA and cholangiocarcinoma: Further studies revealed that exogenous CypA stimulates the proliferation of pancreatic cancer cells by activating the ERK1/2 and p38 MAPK signaling pathways and by increasing the secretion of interleukin IL-5 and IL-17 in pancreatic cancer cells.103 In human cholangiocarcinoma tissues, overexpressed CypA enhances cholangiocarcinoma cell proliferation via direct interacting with CD147, along with activation of the ERK1/2 and p38 MAPK signaling pathways.98 In HCC, it has been found that CypA was higher expressed in HCC tissues than in adjacent tissues.