TNC and breast carcinoma: These results are supported by another study in the 4T1 orthotopic model of breast cancer, where S100A4+ stromal cells were found to promote metastatic colonization to the lungs by producing high levels of tenascin C. In addition, tail vein-injected 4T1 cells showed a significantly lower efficiency of final engraftment in the lungs in tenascin C knockout mice (120).