Krüppel-like Transcription Factor KLF10 Suppresses TGFβ-Induced Epithelial-to-Mesenchymal Transition via a Negative Feedback Mechanism

Abstract

TGFb-SMAD signaling exerts a contextual effect that suppresses malignant growth early in epithelial tumorigenesis but promotes metastasis at later stages. Longstanding challenges in resolving this functional dichotomy may uncover new strategies to treat advanced carcinomas. The Kruppel-like transcription factor, KLF10, is a pivotal effector of TGF beta/SMAD signaling that mediates antiproliferative effects of TGF beta. In this study, we show how KLF10 opposes the prometastatic effects of TGFb by limiting its ability to induce epithelial-to-mesenchymal transition (EMT). KLF10 depletion accentuated induction of EMT as assessed by multiple metrics. KLF10 occupied GC-rich sequences in the promoter region of the EMT-promoting transcription factor SLUG/SNAI2, repressing its transcription by recruiting HDAC1 and licensing the removal of activating histone acetylation marks. In clinical specimens of lung adenocarcinoma, low KLF10 expression associated with decreased patient survival, consistent with a pivotal role for KLF10 in distinguishing the antiproliferative versus prometastatic functions of TGFb. Our results establish that KLF10 functions to suppress TGFb-induced EMT, establishing a molecular basis for the dichotomy of TGFb function during tumor progression. (C) 2017 AACR.