Gene amplification-associated overexpression of the RNA editing enzyme ADAR1 enhances human lung tumorigenesis

The introduction of new therapies against particular genetic mutations in non-small-cell lung cancer is a promising avenue for improving patient survival, but the target population is small. There is a need to discover new potential actionable genetic lesions, to which end, non-conventional cancer pathways, such as RNA editing, are worth exploring. Herein we show that the adenosine-toinosine editing enzyme ADAR1 undergoes gene amplification in non-small cancer cell lines and primary tumors in association with higher levels of the corresponding mRNA and protein. From a growth and invasion standpoint, the depletion of ADAR1 expression in amplified cells reduces their tumorigenic potential in cell culture and mouse models, whereas its overexpression has the opposite effects. From a functional perspective, ADAR1 overexpression enhances the editing frequencies of target transcripts such as NEIL1 and miR-381. In the clinical setting, patients with early-stage lung cancer, but harboring ADAR1 gene amplification, have poor outcomes. Overall, our results indicate a role for ADAR1 as a lung cancer oncogene undergoing gene amplification-associated activation that affects downstream RNA editing patterns and patient prognosis.This work was supported by the European Research Council under the European Community's Seventh Framework Programme (FP7/2007-2013)/ERC grant agreement no. 268626—EPINORC project, the Grant agreement number HEALTH-F2-2010-258677—CURELUNG project, the Spanish Ministry of Economy and Competitiveness (MINECO Projects no. SAF2011-22803, PI13-01339 and SAF2014-55000- R), the Institute of Health Carlos III (ISCIII)—PI10/02992, Ministerio de Educación, Ciencia e Innovación Grant SAF2010-14935, the Cellex Foundation, the National Cancer Center Research and Development Fund (NCC Biobank: 23 A-1) and the Health and Science Departments of the Catalan Government (Generalitat de Catalunya) AGAUR—project no. 2009SGR1315 and 2014SGR633.Peer Reviewe

The immunopeptidome landscape associated with T cell infiltration, inflammation and immune editing in lung cancer.

One key barrier to improving efficacy of personalized cancer immunotherapies that are dependent on the tumor antigenic landscape remains patient stratification. Although patients with CD3 <sup>+</sup> CD8 <sup>+</sup> T cell-inflamed tumors typically show better response to immune checkpoint inhibitors, it is still unknown whether the immunopeptidome repertoire presented in highly inflamed and noninflamed tumors is substantially different. We surveyed 61 tumor regions and adjacent nonmalignant lung tissues from 8 patients with lung cancer and performed deep antigen discovery combining immunopeptidomics, genomics, bulk and spatial transcriptomics, and explored the heterogeneous expression and presentation of tumor (neo)antigens. In the present study, we associated diverse immune cell populations with the immunopeptidome and found a relatively higher frequency of predicted neoantigens located within HLA-I presentation hotspots in CD3 <sup>+</sup> CD8 <sup>+</sup> T cell-excluded tumors. We associated such neoantigens with immune recognition, supporting their involvement in immune editing. This could have implications for the choice of combination therapies tailored to the patient's mutanome and immune microenvironment

Corrigendum: Gene amplification-associated overexpression of the RNA editing enzyme ADAR1 enhances human lung tumorigenesis

Correction to: Oncogene (2016) 35, 4407–4413; doi:10.1038/onc.2015.469; published online 7 December 2015.Peer Reviewe