ATF5 and cancer: The leucine zipper transcription factors ATF5 (Activating Transcription Factor 5), CEBPB (CCAAT Enhancer Binding Protein Beta) and CEBPD (CCAAT Enhancer Binding Protein Delta) play significant roles in a wide variety of malignancies by promoting cancer formation, growth, survival, metastasis and treatment resistance [1,2,3,4,5,6,7,8,9].