Project description:Immune checkpoint blockade (ICB) has shown remarkable clinical efficacy across multiple cancer types. However, only a fraction of patients respond to ICB. Here, we performed pooled mutagenic screening with CRISPR-mediated genetically engineered mouse models (CRISPR-GEMMs) in ICB settings, and identified KMT2D as a major modulator of ICB response across multiple cancer types. Kmt2d encodes a histone H3K4 methyltransferase and is among the most frequently mutated genes in cancer patients. Kmt2d loss led to increased DNA damage and mutation burden, chromatin remodeling, intron retention, and activation of transposable elements. Additionally, Kmt2d-deficient cells exhibit increased protein turnover and IFN-γ-stimulated antigen presentation. In turn, Kmt2d-mutant tumors in both mouse and human are characterized by increased immune infiltration. These data demonstrate that KMT2D deficiency sensitizes tumors to ICB by augmenting tumor immunogenicity, highlighting the power of CRISPR-GEMMs for interrogating complex molecular landscapes in immunotherapeutic contexts that preserve the native tumor microenvironment.
Project description:Immune checkpoint blockade (ICB) has shown remarkable clinical efficacy across multiple cancer types. However, only a fraction of patients respond to ICB. Here, we performed pooled mutagenic screening with CRISPR-mediated genetically engineered mouse models (CRISPR-GEMMs) in ICB settings, and identified KMT2D as a major modulator of ICB response across multiple cancer types. Kmt2d encodes a histone H3K4 methyltransferase and is among the most frequently mutated genes in cancer patients. Kmt2d loss led to increased DNA damage and mutation burden, chromatin remodeling, intron retention, and activation of transposable elements. Additionally, Kmt2d-deficient cells exhibit increased protein turnover and IFN-γ-stimulated antigen presentation. In turn, Kmt2d-mutant tumors in both mouse and human are characterized by increased immune infiltration. These data demonstrate that KMT2D deficiency sensitizes tumors to ICB by augmenting tumor immunogenicity, highlighting the power of CRISPR-GEMMs for interrogating complex molecular landscapes in immunotherapeutic contexts that preserve the native tumor microenvironment.
Project description:We introduce poly-adenine CRISPR gRNA-based single cell RNA-sequencing (pAC-Seq), a method enabling simultaneous observation of mutagenic guide RNAs (gRNAs) and their transcriptional consequences in single cell RNA sequencing (scRNA-seq) data. We have made gRNAs robustly visible in scRNA-seq data while maintaining full activity by modifying them with a hardcoded poly-adenine tract. We apply pAC-Seq to study the transcriptomic effects of non-coding CRISPR/Cas9-induced mutations in a pooled screening format. pAC-Seq is a simple, robust, and broadly applicable method of measuring the global effects of genomic mutation.
Project description:CD8+ T cells can be reprogrammed for better persistence and robust effector function in TME. By performing an in vivo pooled CRISPR-Cas9 mutagenesis screening of metabolism-associated factors, we identify Regnase-1 as a major negative regulator of antitumor responses, whose deficiency results in drastically increased CD8+ T cell accumulation in tumors
Project description:CD8+ T cells can be reprogrammed for better persistence and robust effector function in TME. By performing an in vivo pooled CRISPR-Cas9 mutagenesis screening of metabolism-associated factors, we identify Regnase-1 as a major negative regulator of antitumor responses, whose deficiency results in drastically increased CD8+ T cell accumulation in tumors
Project description:CD8+ T cells can be reprogrammed for better persistence and robust effector function in TME. By performing an in vivo pooled CRISPR-Cas9 mutagenesis screening of metabolism-associated factors, we identify Regnase-1 as a major negative regulator of antitumor responses, whose deficiency results in drastically increased CD8+ T cell accumulation in tumors
Project description:CD8+ T cells can be reprogrammed for better persistence and robust effector function in TME. By performing an in vivo pooled CRISPR-Cas9 mutagenesis screening of metabolism-associated factors, we identify Regnase-1 as a major negative regulator of antitumor responses, whose deficiency results in drastically increased CD8+ T cell accumulation in tumors
