ACTA2 and neoplasm: Together with the findings that Cav1-silencing induced a more reactive phenotype of HS5 fibroblasts as revealed by the upregulation of the reactive fibroblasts markers Acta2 and Tagln as well as reduced Mmp2 mRNA expression levels in vitro, the phenotype and activation state of the fibroblasts seems to be more important than the amount of these cells within a tumor.