Project description:The UTX/KDM6A gene encodes the UTX histone H3K27 demethylase, which plays an important role in mammalian development and is frequently mutated in cancers and particularly, in urothelial cancers. Using BioID technique, we explored the interactome of different UTX isoforms.
Project description:Large-scale genome sequencing efforts of human tumors identified epigenetic modifiers as one of the most frequently mutated gene class in human cancer. However, how these mutations drive tumor development and progression is largely unknown. Here, we identify the histone demethylase KDM6A as an important tumor suppressor in solid cancers, such as liver cancer and pancreatic cancer. KDM6A-deficient tumors show hyperactivation of mTORC1 signaling, whereas endogenous KDM6A re-expression in established KDM6A-deficient tumors diminishes mTORC1 activity by fostering the expression of crucial negative pathway regulators, such as DEPTOR, TSC1, and TSC2, resulting in tumor regression. Importantly, KDM6A expression in human tumors correlates with mTORC1 activity and KDM6A-deficient tumors exhibit increased sensitivity to mTORC1 inhibition. Hence, our results link KDM6A-dependent epigenetic remodeling to mTORC1 signaling and provide a potential therapeutic strategy for KDM6A-deficient tumors.
Project description:KDM6A is a histone demethylase that remove H3K27me3 lysine. This study compares the histone modification pattern between WT and KDM6A KO cells.
Project description:Genome-wide studies characterizing mutational landscape of bladder cancer revealed the exceptionally high rate of chromatin modifier genes in bladder cancer. Thus, epigenetic deregulation is a critical theme which needs further investigation for bladder cancer research. One of the highly mutated genes in bladder cancer is KDM6A, functioning as H3K27 demethylase and part of MLL3/4 complexes. To decipher the role of KDM6A in normal vs tumor setting, we identified the genomic localization profiles of KDM6A in normal, immortalized and cancer bladder cells. Our results showed differential occupancy of KDM6A at the genes involved in cell differentiation, chromatin organization and Notch signaling depending on the cell type and the mutation status of KDM6A. Transcription factor motif analysis revealed an enrichment for HES1 for the KDM6A peaks identified for T24 bladder cancer cell line, which has a truncating mutation in KDM6A and lacking demethylase domain and also for the other clusters showing KDM6A localization. For the first time, using co-immunoprecipitation experiments, we show that KDM6A is in complex with TLE co-repressors and HES1, and illustrate the potential interaction of KDM6A with TLE co-repressors, HES1, RUNX, HHEX transcription factors by computational structural biology models. Our work makes important contributions to the understanding of KDM6A malfunction in bladder cancer and provides models for the functioning of KDM6A independent of its demethylase activity.
