CAV1 and breast carcinoma: To specifically address the role of Cav1 in the tumor stroma, primary mouse embryonic fibroblasts (pMEFs) derived from either wild-type (Cav1WT) or Cav1 knockout (Cav1KO) mice were co-injected with LM-4175 tumor cells, a cell line of a lung metastasis derived MDA-MB-231 breast cancer cells (Minn et al., 2005).