Table 1.

Commonly used biomarkers of CAFs and their characteristics.

Expression site	Biomarker	Cross-expressed cell	Cancer with CAFs that express the marker	Biological function	Ref.
Cell membrane	FAP	•Reactive stromal fibroblasts •Resting mesoderm cells •CD45-positive immune cells	Breast cancer, lung cancer, colorectal, renal cancer, and ovarian cancer, etc.	Promoting tumor metastasis, immune evasion, and ECM remolding	77, 78, 79
	PDGFRα/β	•Normal fibroblasts •Pericytes •Vascular smooth muscle cells •Skeletal muscle cells •Cardiomyocytes •Tumor cells	Breast cancer, colorectal cancer, and cervical cancer, etc.	Promoting tumor metastasis, M2 macrophage polarization, angiogenesis	80,81
	CAVEOLIN-1	•Adipocytes •Endothelial cells •Normal fibroblasts •Type I alveolar cells •Tumor cells	Pancreatic cancer, breast cancer, and gastric cancer, etc.	Promoting tumor invasion	82,83
	CD10	•Pre-B lymphocytes	Breast cancer, colorectal cancer, and gastric cancer, etc.	Promoting tumor cell stemness	84, 85, 86
	GPR77	•Polynuclear neutrophilic leukocytes	Breast cancer, gastric cancer, and ovarian cancer, etc.	Promoting tumor progression	87,88
	ITGA5	•Lung squamous cell	Breast cancer, colorectal cancer, and glioblastoma, etc.	Promoting tumor metastasis, tumor cell stemness, and angiogenesis	89,90
	NG2	•Normal fibroblasts •Neuroglia •Tumor cells	Breast cancer, melanoma, squamous cell cancer, neuroblastoma, mesothelioma	Promoting tumor cell migration	91, 92, 93
Cytoplasmic	α-SMA	•Normal fibroblasts •Pericytes, •Smooth muscle cells •Cardiomyocytes	Pancreatic cancer, breast cancer, lung cancer, liver cancer, colon cancer, and renal cancer, etc.	Promoting tumor cell proliferation, ECM remodeling, and tumor cell stemness	94,95
	VIMENTIN	•Epithelial cells •Endothelial cells •Neurons	PDAC, breast cancer, prostate cancer, lung cancer, gastric cancer, etc.	Promoting tumor cell growth, invasion, and migration	96, 97, 98
	S100A4/FSP-1	•Normal fibroblasts •Epithelial cells •Macrophages •Tumor cells	Breast cancer, lung cancer, gastric cancer, endometrioid adenocarcinoma, etc.	Promoting tumor metastasis, immune evasion	99
	DESMIN	•Skin fibroblasts •Pericytes •Myocytes	Colorectal cancer, and gastric cancer, etc.	Promoting tumor cell growth, invasion, and migration	100,101
ECM protein	TENASCIN-C	•Normal fibroblasts •Tumor cells •Endothelial cells	Pancreatic cancer, breast cancer, prostate cancer, and cervical cancer, etc.	Promoting tumor metastasis and angiogenesis	102, 103, 104
	PERIOSTIN	•Normal fibroblasts, •Tumor cells •Mesenchymal stem cells	Breast cancer, lung cancer, prostate cancer, and esophageal squamous cell cancer, etc.	Promoting tumor cell stemness, invasion and metastasis	105, 106, 107

‒, not applicable. CAFs, cancer-associated fibroblasts; FAP, fibroblast activation protein; CD, cluster of differentiation; ECM, extracellular matrix; PDGFRα/β, platelet growth factor receptor α/β; GPR77, G protein-coupled receptor 77; ITGA5, integrin alpha5; NG2, chondroitin sulfate proteoglycan; α-SMA, α-smooth muscle actin; PDAC, pancreatic ductal adenocarcinoma; EMT, epithelial–mesenchymal transition; FSP-1, fibroblast-specific protein-1.