It has been reported that notable and infamous players in cancer initiation and progression, which are not treatable by conventional therapies, include transcription factors (such as p53, MYC, E2F, or Kruppel-like factor 4 (KLF4)), phosphatases (such as PP2δ, PP2A, or PTP1B), and the well-known RAS family. Here, KLF4 is linked to cancer.