Inflammatory fibroblasts in cancer

The association between inflammation and cancer has been studied widely. Indeed, the tumor microenvironment is influenced by inflammatory cells and affects tumor progression, tumor growth, and the survival of cancer cells. Also, the tumor microenvironment is essential to invasion and metastasis of cancer. Fibroblasts, immune cells, the extracellular matrix and other various components all constitute the tumor stroma, ordinarily referred to as the 'reactive stroma'. Cancer-associated fibroblasts (CAFs), which are activated fibroblasts and one of the components of the tumor microenvironment, are associated with cancer progression, invasiveness and metastasis, and their functional contributions to these processes are beginning to emerge. CAFs mediate tumor-promoting inflammation through various signaling pathways. Epithelial-mesenchymal transition is a process for producing mesenchymal cells during invasion and metastasis of cancer cells. Fibroblasts have been identified as a key player in this mechanism. In the present review, we summarize the relationships between fibroblasts, inflammatory response, the tumor microenvironment and cancer progression. This review provides useful information for the development of cancer prevention and treatment therapies through controlling the inflammatory responses.