In the context of active TGFβ signaling, we found that NDRG1 is only involved in the metastatic abilities of TNBC cells that have previously metastasized to distant tissues, which is supported by the notion that breast tumor cells from pleural effusion have a different gene profile compared to their counterparts in primary tumors and express metastasis-related pathways such as TGFβ 54. This evidence concerns the gene NDRG1 and Pleural effusion.