Our previous studies have shown that metformin, mifepristone, the bromodomain 4 (BRD4) inhibitors 19, mithramycin A 20, CDK7 inhibitor 19, PRMT5 inhibitor 21, RSK2 inhibitor 22, and HDAC inhibitor 23 retard tumor growth by downregulating KLF5 expression 10, 19, 24. The gene discussed is KLF5; the disease is neoplasm.