ACTA1 and carcinoma: We first separated and cultured primary carcinoma-associated fibroblasts (CAFs) from a female patient with Duke B colorectal adenocarcinoma, and immunostaining confirmed that these cells were positive for fibroblast markers such as vimentin [22], α-SMA [23] and FAP [24] and negative for epithelial cell marker EpCAM [25] (Fig 4A).