KLF4 and cancer: Cancer cells share many cellular and molecular features with ESCs [11], including a rapid proliferation rate [12], upregulated telomerase activity [13], increased expression levels of oncogenes such as c-MYC [14] and Krüppel-like factor 4 (KLF4) [15], similar overall gene expression profiles [16,17], microRNA signatures [18], and epigenetic statuses [19].