GSE210498
TGFß1-Induced EMT in the MCF10A Mammary Epithelial Cell Line Model Is Executed Independently of SNAIL1 and ZEB1 but Relies on JUNB-Coordinated Transcriptional Regulation
Epithelial-mesenchymal transition (EMT) fosters cancer cell invasion and metastasis, the main cause of cancer-related mortality. Growing evidence that SNAIL and ZEB transcription factors, typically portrayed as master regulators of EMT, may be dispensable for this process, led us to re-investigate its mechanistic underpinnings. For this, we used an unbiased computational ap-proach that integrated time-resolved analyses of chromatin structure and differential gene ex-pression, to predict transcriptional regulators of TGFß1-inducible EMT in the MCF10A mam-mary epithelial cell line model. Bioinformatic analyses indicated comparatively minor contri-butions of SNAIL proteins and ZEB1 to TGFß1-induced EMT, whereas the AP-1 subunit JUNB was anticipated to have a much larger impact. CRISPR/Cas9-mediated loss-of-function studies confirmed that TGFß1-induced EMT proceeded independently of SNAIL proteins and ZEB1. In contrast, JUNB was necessary and sufficient for EMT in MCF10A cells, but not in A549 lung can-cer cells, indicating cell-type-specificity of JUNB EMT-regulatory capacity. Nonetheless, the JUNB-dependence of EMT-associated transcriptional reprogramming in MCF10A cells allowed to define a gene expression signature which was regulated by TGFß1 in diverse cellular back-grounds, showed positively correlated expression with TGFß signaling in multiple cancer tran-scriptomes, and was predictive of patient survival in several cancer types. Altogether, our find-ings provide novel mechanistic insights into the context-dependent control of TGFß1-driven EMT and thereby may lead to improved diagnostic and therapeutic options. Overall design: Comparative gene expression profiling analysis of RNA-seq data for MCF10A cells with wild-type or inactivated JUNB genes and treated with TGF-beta1 or solvent for different time periods.