Cancer-associated fibroblasts (CAFs) are key components of the tumor microenvironment (TME) and play an essential role in the development of tumors. It is suggested that CAFs influence tumor cell proliferation, invasion and migration as well as regulate tumor cell resistance to chemotherapeutic agents through the secretion of cytokines, chemokines, growth factors and extracellular matrix proteins. And they also enhance the immune escape ability of tumors by interacting with tumor-associated immune cells. This article comprehensively expounds how the biomarkers and subtypes of CAFs can promote the development of malignant tumors by affecting the immune escape of tumor cells and TME, and discusses the mechanism and potential treatment strategies of CAFs in malignant tumors.

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