In order to examine the contribution of TEC‐derived myofibroblasts and active fibroblasts to in vivo tumor growth, we mixed the TECs treated with TGF‐β2 (termed End‐MyoT TECs) or those treated with TGF‐β2 and FGF2 (termed End‐N‐MyoT TECs) with A375 human melanoma cells in a 3 : 10 ratio and grafted these mixtures subcutaneously into the immunodeficient mice. Here, FGF2 is linked to melanoma.