Table 1 Frequently used makers for identifying CAFs

PDPN

Transmembrane glycoprotein involved in cellular adhesion and signaling

Promotes resistance to EGFR-TKIs; initiates tertiary lymphoid structure (TLS) formation

Expressed in epithelial tumor cells, inflammatory macrophages, and CAFs

[19, 91,92,138, 204]

FSP1/S100A4

Calcium-binding protein that regulates cell motility and metastasis

Modulates malignant cell metabolism via FAK-mediated pathways; expression correlates with poor prognosis

Highly expressed in prostate cancer and breast cancer (BC)

[15, 21, 22, 32, 129]

PDGFRα/β

Tyrosine kinase receptors that mediate growth factor signaling

Drives immune suppression, angiogenesis, and hormone therapy resistance

Expressed on fibroblasts, neural progenitors, pericytes, and astrocytes

[16, 115, 122, 163, 252]

αSMA

Highly conserved protein essential for cytoskeletal integrity and contractility

Defines myofibroblast contractility; regulates ECM remodeling

Expressed in smooth muscle cells, pericytes, and activated CAFs

[4, 17, 18, 42]

FAPα

Type II transmembrane serine protease whose expression is linked to tissue repair and fibrosis

Remodels ECM; suppresses immunity; expression is associated with poor prognosis

Expressed during wound healing, in fetal placenta, and CAFs

[77, 87, 100, 160,161,162, 173, 176]