KLF4 and breast cancer: Specifically, ANGPTL4 and KLF4 were both highly expressed in metastatic breast cancer (Fig. 8J), and further co-expression analysis indicated that ANGPTL4 and KLF4 were simultaneously expressed in breast cancer tissue microarray (R = 0.3610, p = 0.0183, n = 44) (Fig. 8L).