Programmable in vivo CRISPR activation elucidates the oncogenic and immunosuppressive role of MYC in lung adenocarcinoma

Abstract

Conventional genetically engineered mouse models (GEMMs) are time consuming, laborious and offer limited spatio-temporal control. Here, we describe the development of a streamlined platform for in vivo gene activation using CRISPR activation (CRISPRa) technology. Unlike conventional GEMMs, our model system allows for flexible, sustained and timed activation of one or more target genes using single or pooled lentiviral guides. Using Myc and Yap1 as model oncogenes, we demonstrate gene activation in primary pancreatic organoid cultures in vitro and enhanced tumorigenic potential in Myc-activated organoids when transplanted orthotopically. By implementing our model as an autochthonous lung cancer model, we show that transduction-mediated Myc activation leads to accelerated tumor progression and significantly reduced overall survival relative to non-targeted tumor controls. Furthermore, we found that Myc-activation led to the acquisition of an immune suppressive cold tumor microenvironment. Through cross-species validation of our results using publicly available RNA/DNA-seq data sets, we were able to link MYC to a previously described, immunosuppressive transcriptomic subtype in patient tumors, thus identifying a patient cohort that may benefit from combined MYC/immune-targeted therapies. Overall, our work demonstrates how CRISPRa can be used for rapid functional validation of putative oncogenes and may allow for the identification and evaluation of potential metastatic and oncogenic drivers through competitive screening.

Molecular Mechanisms of Gynostemma pentaphyllum in Prevention and Treatment of Non-Small-Cell Lung Cancer

“…Three candidate targets with higher degree values in the core PPI network, MYC, ESR1, and HIF1A, were subjected to further molecular docking and analysis, and it was revealed that the three core targets had good affinity with the active compounds of G. pentaphyllum , referring to quercetin and MYC, rhamnazin and ESR1, and quercetin and HIF1A. c-Myc regulates multiple genes, which are associated with cell proliferation in many cancers, including NSCLC [ 32 ]. Guo et al demonstrated quercetin notably repressed cancer cell proliferation by downregulating c-Myc expression in pancreatic ductal adenocarcinoma [ 33 ].…”