Molecular mechanism of pancreatic ductal adenocarcinoma: The heterogeneity of cancer-associated fibroblasts and key signaling pathways

Table 1 Characteristics and functions of cancer-associated fibroblasts subtypes

Types	Origin	Markers	Role in TME
MyCAFs	Pancreatic cells, PSCs	α-SMA, FAP, SMA, PDGFβ	Facilitate tumor cell invasion, migration, drug resistance[23-27]
ICAFs	Bone marrow-originated monocytes	IL-6, IL-1β	Promote tumor inflammation, immune evasion, tumor progression[25,26,33,34]
ApCAFs	Mesenchymal cells	MHC-II, RORγt	Enhance tumor aggression, amplify immune checkpoint inhibitor efficacy[25,35,36]

MyCAF: Myofibroblast-like cancer-associated fibroblast; ICAF: Inflammatory cancer-associated fibroblast; ApCAF: Antigen-presenting cancer-associated fibroblast; PSC: Pancreatic stellate cell; TME: Tumor microenvironment.