Targeting Krüppel-like factor 5 (KLF5) for cancer therapy.

Krüppel-like factor 5 (KLF5) belongs to a family of zinc-finger-containing transcription factors which are involved in regulating expression of a wide range of genes, thereby affecting diverse cellular functions. The activities of KLF5 are regulated by multiple signaling pathways including Wnt, Ras, TGFβ, Hippo, Notch, retinoid acid receptor, and hormone receptors. The expression of KLF5 is frequently abnormal in human cancers and the functions of KLF5 are context dependent. Accumulating evidence suggests that KLF5 represents a novel therapeutic target for cancer therapy. In this review, we discuss the potential biological functions of KLF5 associated with several key signaling pathways that are relevant to cancer as well as the involvement of KLF5 in various human cancers. We also describe the progress in the discovery and development of small molecules targeting KLF5 as potential therapeutics that may benefit cancer patients. The challenges and future research directions on the drug discovery of KLF5 ligands are also presented.