KLF4 and metastatic neoplasm: Firstly, we performed the TF enrichment analysis between primary tumors and metastatic tumors, and finally, seven TFs were identified as differentially expressed TFs, including CBX2, CDX2, FOXA2, KLF4, NANOG, NCAPG, and TFAP2A, which was demonstrated in a heatmap (Fig. 6A) and a volcano plot (Fig. 6B).