Project description:The dysregulation of the histone H3 lysine 36 (H3K36) methyltransferase, SETD2, is associated with worse clinical outcomes and metastasis in clear cell Renal Cell Carcinoma (ccRCC). Here, we reveal that kidney cancer cells displaying diminished H3K36me3 levels (SETD2 deficiency) show increased sensitivity to the anti-tumor effects of the DNA hypomethylating agent 5-aza-2’-deoxycytidine (Decitabine/DAC). DAC treatment induced stronger viral mimicry activation and immunostimulatory signals by higher transposable element (TE) expression in SETD2-mutant cancer cells. Surprisingly, we demonstrate that the increased TE abundance in SETD2-knockout (SETD2-KO) kidney cancer cells is substantially derived from mis-spliced products induced by DAC treatment. Epigenetic profiling suggests that differential DNA methylation, H3K36me3, and H3K9me3 marks across exons and intronic TEs might contribute to elevated mis-splicing rates specifically in the SETD2 loss context. Finally, SETD2 dysregulation also sensitized tumors in vivo to combinatorial therapy of DAC and immune checkpoint inhibitors highlighting the translational potential for this precision medicine.
Project description:Tumors with mutations in chromatin regulators present attractive targets for DNA hypomethylating agent 5-aza-2'-deoxycytidine (DAC) therapy, which further disrupts cancer cells' epigenomic fidelity and reactivates transposable element (TE) expression to drive viral mimicry responses. SETD2 encodes a histone methyltransferase (H3K36me3) and is prevalently mutated in advanced kidney cancers. Here, we show that SETD2-mutant kidney cancer cells are especially sensitive in vitro and in vivo to DAC treatment. We find that the viral mimicry response are direct consequences of mis-splicing events, such as exon inclusions or extensions, triggered by DAC treatment in an SETD2-loss context. Comprehensive epigenomic analysis reveals H3K9me3 deposition, rather than DNA methylation dynamics, across intronic TEs might contribute to elevated mis-splicing rates. Through epigenomic and transcriptomic analyses, we show that SETD2-deficient kidney cancers are prone to mis-splicing, which can be therapeutically exacerbated with DAC treatment to increase viral mimicry activation and provide synergy with combinatorial immunotherapy approaches.
Project description:The dysregulation of the histone H3 lysine 36 (H3K36) methyltransferase, SETD2, is associated with worse clinical outcomes and metastasis in clear cell Renal Cell Carcinoma (ccRCC). Here, we reveal that kidney cancer cells displaying diminished H3K36me3 levels (SETD2 deficiency) show increased sensitivity to the anti-tumor effects of the DNA hypomethylating agent 5-aza-2’-deoxycytidine (Decitabine/DAC). DAC treatment induced stronger viral mimicry activation and immunostimulatory signals by higher transposable element (TE) expression in SETD2-mutant cancer cells. Surprisingly, we demonstrate that the increased TE abundance in SETD2-knockout (SETD2-KO) kidney cancer cells is substantially derived from mis-spliced products induced by DAC treatment. Epigenetic profiling suggests that differential DNA methylation, H3K36me3, and H3K9me3 marks across exons and intronic TEs might contribute to elevated mis-splicing rates specifically in the SETD2 loss context. Finally, SETD2 dysregulation also sensitized tumors in vivo to combinatorial therapy of DAC and immune checkpoint inhibitors highlighting the translational potential for this precision medicine.
