Krüppel-like Factors 4 and 5 in Colorectal Tumorigenesis

SIMPLE SUMMARY: Krüppel-like factors (KLFs) are zinc finger-containing transcription factors that play a crucial role in embryogenesis, development, homeostasis, and disease progression by regulating multiple signaling pathways. This review is focused on the role of two members of the KLF family, KLF4 and KLF5, and their intricate roles in colorectal carcinogenesis. ABSTRACT: Krüppel-like factors (KLFs) are transcription factors regulating various biological processes such as proliferation, differentiation, migration, invasion, and homeostasis. Importantly, they participate in disease development and progression. KLFs are expressed in multiple tissues, and their role is tissue- and context-dependent. KLF4 and KLF5 are two fascinating members of this family that regulate crucial stages of cellular identity from embryogenesis through differentiation and, finally, during tumorigenesis. They maintain homeostasis of various tissues and regulate inflammation, response to injury, regeneration, and development and progression of multiple cancers such as colorectal, breast, ovarian, pancreatic, lung, and prostate, to name a few. Recent studies broaden our understanding of their function and demonstrate their opposing roles in regulating gene expression, cellular function, and tumorigenesis. This review will focus on the roles KLF4 and KLF5 play in colorectal cancer. Understanding the context-dependent functions of KLF4 and KLF5 and the mechanisms through which they exert their effects will be extremely helpful in developing targeted cancer therapy.