Fibroblasts in cancer

Fibroblasts are an important component of the tumour microenvironment. They become activated in tumours, as they do in healing wounds. Here, their roles in tumour initiation, progression and metastasis are reviewed. Key Points Fibroblasts are a key cellular component of tumours. Activated fibroblasts (which are sometimes referred to as myofibroblasts) that are found in association with cancer cells are known as carcinoma-associated fibroblasts (CAFs). The role of fibroblasts in the origin and initiation of cancer invasion is poorly understood, but recent evidence indicates that they can provide oncogenic signals to the transformed epithelia in a paracrine fashion. Some studies indicate that myofibroblasts might facilitate angiogenesis and cancer progression. Epithelial-to-mesenchymal transition is a source for converting epithelial cells into fibroblast-like cells in various tissues. Fibroblasts might also have a role in metastasis. Therapies against CAFs are being considered as a way to control cancer. Tumours are known as wounds that do not heal — this implies that cells that are involved in angiogenesis and the response to injury, such as endothelial cells and fibroblasts, have a prominent role in the progression, growth and spread of cancers. Fibroblasts are associated with cancer cells at all stages of cancer progression, and their structural and functional contributions to this process are beginning to emerge. Their production of growth factors, chemokines and extracellular matrix facilitates the angiogenic recruitment of endothelial cells and pericytes. Fibroblasts are therefore a key determinant in the malignant progression of cancer and represent an important target for cancer therapies.