To further address if human mesenchymal cells could be replaced by recipient mouse fibroblasts, we performed anti-mouse and human vimentin antibodies respectively and found that anti-mouse vimentin was negative while positive of anti-human vimentin in tumor tissue (Fig. 3E), demonstrating that human mesenchymal cells were not replaced by recipient mouse fibroblasts in this mouse model. Here, VIM is linked to neoplasm.