E2F4 and breast cancer: For example, HNF4A, which can promote the metastasis of liver cancer, was shown to be closely associated with the epithelial-mesenchymal transition (EMT)[42]; E2F4 has been shown to be minimally expressed in breast cancer and is associated with the occurrence of metastasis[43]; and ERG has been shown to promote metastasis of prostate cancer[44].