ACTA1 and neoplasm: To date there has been two major CAF subtypes reported which includes myofibroblastic CAFs (myCAFs), these express a high level of α-smooth muscle actin (αSMA) and reside closely to the tumour and inflammatory CAFs (iCAFs) which express lower levels of αSMA but high levels of chemokines and cytokines and locate more distally from the tumour (Öhlund et al. 2017).