Biology subjects

Nemenoff, R. A.

Publications and source records attributed to Nemenoff, R. A..

15 recordsLinked to original sources

bioRxiv2026

Targeting wild type NTRK decreases brain metastases of lung cancers non-driven by NTRK fusions

The central nervous system (CNS) is a common site of metastatic spread for both non-small cell and small cell lung cancer, yet the therapeutic strategies to prevent and decrease lung cancer brain metastases remain limited. Tyrosine kinase inhibitors have shown promising results in increasing the overall response in brain metastases, owing to their brain penetrance and increased effectiveness; however, their use is limited to the small group of tumors carrying specific oncogenic drivers. Among these, inhibitors with activity against neurotrophic tyrosine receptor kinases (NTRKs) are showing promising effects in reducing CNS metastases in cancers driven by gene rearrangements of these drugs targets. However, wild-type NTRKs are susceptible to activation by their canonical ligands, which are expressed throughout the brain metastatic niche and can, in a paracrine manner, activate NTRK function in cancer cells. Here we show that NTRKs are expressed in primary tumors, brain metastases, and lung cancer cells with various driver mutations expressing wild-type NTRK2 (WT-TrkB). We demonstrate that WT-TrkB activates downstream signaling and proliferation in response to exogenous BDNF and conditioned media from reactive astrocytes known to secrete BDNF in the brain niche. Importantly, the FDA-approved NTRK inhibitor entrectinib blocked BDNF and astrocyte-induced survival pathways in multiple lung cancer cell lines, decreased their proliferation in vitro, and effectively prevented brain metastatic colonization and progression in vivo without significant effects on extracranial disease. Thus, these studies suggest that brain-dependent activation of NTRK is critical for brain metastases of WT-NTRK+ lung cancers, and therefore, NTRK inhibitors can be used to target non-fusion NTRK function to prevent or decrease brain metastases. SIGNIFICANCEThese studies demonstrate that NTRK wild-type receptors are important drivers of brain metastatic colonization and progression in different subtypes of lung cancer, independent of their driver alterations. Thus, they provide rationale to expand the use of FDA-approved NTRK inhibitors with brain penetrance for the prevention of CNS metastases.

cancer biology↗

bioRxiv2026

YAP/TEAD drives treatment-induced adaptive immunosuppression in EGFR-mutant lung cancer

Residual disease remains a major obstacle for achieving durable responses in patients treated with oncogene-targeted therapy. Drug-tolerant persister (DTP) cells emerging under treatment and persisting in residual tumors are considered to be the root of acquired resistance, yet their contribution to immune evasion in on-treatment tumors is poorly defined. Here, we show in the context of EGFR-mutant lung cancer that DTP cells actively contribute to the formation of an immunosuppressive tumor microenvironment during EGFR tyrosine kinase inhibitor (TKI) therapy. In syngeneic mouse models and in patients, EGFR TKI therapy leads to an accumulation of immunosuppressive macrophages, which is strictly treatment-dependent and fully reversible upon treatment cessation or progressive disease, respectively. Quiescent DTP cells directly drive the recruitment and immunosuppressive reprogramming of monocytes and macrophages through a YAP-driven secretome, and the DTP-reprogrammed monocytes suppress T cell proliferation and effector functions in vitro. Co-targeting YAP with a TEAD inhibitor ORM-47286 rewires the DTP secretome and inhibits macrophage reprogramming in vitro, and prevents immunosuppressive macrophage accumulation and improves the efficacy of EGFR TKI therapy in immunocompetent mouse models. Our findings highlight the previously unappreciated role of DTP cells in modulating the tumor microenvironment in on-treatment tumors, and position the treatment-induced YAP/TEAD activity in DTP cells as an important driver of adaptive immunosuppression during EGFR-targeted therapy.

cancer biology↗

bioRxiv2025

Modeling acquired TKI resistance and effective combination therapeutic strategies in murine RET+ lung adenocarcinoma

RET gene rearrangements yield oncogenic fusion proteins that drive a subset of lung adenocarcinomas (LUAD). The tyrosine kinase inhibitors (TKIs) selpercatinib and pralsetinib are approved therapies for RET+ lung cancers and have markedly improved clinical outcomes in these patients, but acquired resistance remains a hurdle to their durable management. Using a recently developed murine model of RET+ lung cancer driven by a Trim24-Ret fusion protein, two Trim24-Ret cell lines (TR.1 and TR.2) were established. Orthotopic lung tumors generated by transplantation of these cell lines initially respond to selpercatinib followed by prompt progression within [~]3 weeks of initiating TKI treatment. Cell lines derived from the selpercatinib-resistant TR.1 and TR.2 tumors exhibited in vitro sensitivity to MET and ERBB-targeted TKIs, indicating acquired bypass signaling through these receptor tyrosine kinases. Moreover, the selpercatinib-resistant TR.1 and TR.2 cell lines exhibited increased sensitivity to MEK and PTPN11 inhibitors relative to the parental cell lines, indicating a greater dependence on MAPK pathway signaling. The TKI-resistant cell lines showed no evidence for MET gene amplification, but exhibited varied induction of multiple genes that function within MET and ERBB2:ERBB4 interaction networks including ligands (HGF, NRG1), adaptors (GAB1) and co-receptors (NRP1). Consistent with an important role for MET signaling in driving acquired selpercatinib resistance, mice bearing orthotopic lung tumors derived from TR.1 or TR.2 cells that had progressed on selpercatinib treatment underwent significant re-shrinkage upon co-treatment with the MET inhibitor, crizotinib, although progression re-occurred. By contrast, upfront treatment with selpercatinib and crizotinib in orthotopic tumors yielded complete elimination of 78% of TR.1 tumors and a prolonged duration of response in TR.2 tumors. The findings highlight the failings inherent in treating acquired resistance mechanisms at progression and the potential therapeutic impact of predicting and targeting dominant mechanisms of resistance prior to or early after initiating oncogene-targeting TKI treatment in RTK-driven LUAD.

cancer biology↗

bioRxiv2025

Klf4-dependent pivotal role of smooth muscle-derived Gli1+ lineage progenitor cells in lung cancer progression

Lung cancer remains the leading cause of cancer-related deaths worldwide. Despite the remarkable efficacy of immune checkpoint inhibitors, only a subset of lung adenocarcinoma (LUAD) patients respond and many eventually progress, underscoring the need to develop novel combination therapies. The interaction between cancer cells and the tumor microenvironment (TME), a complex niche including cells of the innate and adaptive immune system, cancer-associated fibroblasts (CAFs), vascular cells, and extracellular matrix (ECM) plays a vital role in tumorigenesis and cancer progression. Using fate mapping, we previously identified a novel subpopulation of resident vascular stem cells derived from vascular smooth muscle cells, designated AdvSca1-SM (vascular Adventitial location, Stem cell antigen-1 expression, SMooth muscle origin) cells. AdvSca1-SM cells are the predominant cell type responding to vessel wall dysfunction and their selective differentiation to myofibroblasts promotes vascular fibrosis. SMC-to-AdvSca1-SM cell reprogramming is dependent on SMC induction of the transcription factor KLF4, and KLF4 is essential for maintenance of the stem cell phenotype. The function of AdvSca1-SM cells in LUAD tumorigenesis has not been explored. Using an orthotopic immunocompetent mouse model of LUAD, we demonstrate that AdvSca1-SM cells are a major component of lung tumors, significantly contributing to cancer associated fibroblasts (CAFs). Compared to AdvSca1-SM cells, CAFs have altered ECM gene expression with a reduction of a stemness signature. AdvSca1-SM-specific genetic ablation of Klf4 altered their phenotype resulting in inhibition of communication between cancer cells and CAFs, decreases in innate immunosuppressive populations, and increased T cell infiltration into the tumor. Targeting this population may represent a novel strategy to improve the response to immunotherapy.

cancer biology↗

bioRxiv2024

KLF4 in smooth muscle cell-derived progenitor cells is essential for angiotensin II-induced cardiac inflammation and fibrosis

Cardiac fibrosis is defined by the excessive accumulation of extracellular matrix (ECM) material resulting in cardiac tissue scarring and dysfunction. While it is commonly accepted that myofibroblasts are the major contributors to ECM deposition in cardiac fibrosis, their origin remains debated. By combining lineage tracing and RNA sequencing, our group made the paradigm-shifting discovery that a subpopulation of resident vascular stem cells residing within the aortic, carotid artery, and femoral aartery adventitia (termed AdvSca1-SM cells) originate from mature vascular smooth muscle cells (SMCs) through an in situ reprogramming process. SMC-to-AdvSca1-SM reprogramming and AdvSca1-SM cell maintenance is dependent on induction and activity of the transcription factor, KLF4. However, the molecular mechanism whereby KLF4 regulates AdvSca1-SM phenotype remains unclear. In the current study, leveraging a highly specific AdvSca1-SM cell reporter system, single-cell RNA-sequencing (scRNA-seq), and spatial transcriptomic approaches, we demonstrate the profibrotic differentiation trajectory of coronary artery-associated AdvSca1-SM cells in the setting of Angiotensin II (AngII)-induced cardiac fibrosis. Differentiation was characterized by loss of stemness-related genes, including Klf4, but gain of expression of a profibrotic phenotype. Importantly, these changes were recapitulated in human cardiac hypertrophic tissue, supporting the translational significance of profibrotic transition of AdvSca1-SM-like cells in human cardiomyopathy. Surprisingly and paradoxically, AdvSca1-SM-specific genetic knockout of Klf4 prior to AngII treatment protected against cardiac inflammation and fibrosis, indicating that Klf4 is essential for the profibrotic response of AdvSca1-SM cells. Overall, our data reveal the contribution of AdvSca1-SM cells to myofibroblasts in the setting of AngII-induced cardiac fibrosis. KLF4 not only maintains the stemness of AdvSca1-SM cells, but also orchestrates their response to profibrotic stimuli, and may serve as a therapeutic target in cardiac fibrosis.

cell biology↗

bioRxiv2024

Inflammation promotes aging-associated oncogenesis in the lung.

BackgroundLung cancer is the leading cause of cancer death in the world. While cigarette smoking is the major preventable factor for cancers in general and lung cancer in particular, old age is also a major risk factor. Aging-related chronic, low-level inflammation, termed inflammaging, has been widely documented; however, it remains unclear how inflammaging contributes to increased lung cancer incidence. AimTo establish connections between aging-associated changes in the lungs and cancer risk. MethodsWe analyzed public databases of gene expression for normal and cancerous human lungs and used mouse models to understand which changes were dependent on inflammation, as well as to assess the impact on oncogenesis. ResultsAnalyses of GTEx and TCGA databases comparing gene expression profiles from normal lungs, lung adenocarcinoma, lung squamous cell carcinoma of subjects across age groups revealed upregulated pathways such as inflammatory response, TNFA signaling via NF{kappa}B, and interferon-gamma response. Similar pathways were identified comparing the gene expression profiles of young and old mouse lungs. Transgenic expression of alpha 1 antitrypsin (AAT) partially reverses increases in markers of aging-associated inflammation and immune deregulation. Using an orthotopic model of lung cancer using cells derived from EML4-ALK fusion-induced adenomas, we demonstrated an increased tumor outgrowth in lungs of old mice while NLRP3 knockout in old mice decreased tumor volumes, suggesting that inflammation contributes to increased lung cancer development in aging organisms. ConclusionsThese studies reveal how expression of an anti-inflammatory mediator (AAT) can reduce some but not all aging-associated changes in mRNA and protein expression in the lungs. We further show that aging is associated with increased tumor outgrowth in the lungs, which may relate to an increased inflammatory microenvironment.

cancer biology↗

bioRxiv2023

Smooth muscle-derived adventitial progenitor cells promote key cell type transitions controlling plaque stability in atherosclerosis in a Klf4-dependent manner

We previously established that vascular smooth muscle-derived adventitial progenitor cells (AdvSca1-SM) preferentially differentiate into myofibroblasts and contribute to fibrosis in response to acute vascular injury. However, the role of these progenitor cells in chronic atherosclerosis has not been defined. Using an AdvSca1-SM lineage tracing model, scRNA-Seq, flow cytometry, and histological approaches, we confirmed that AdvSca1-SM cells localize throughout the vessel wall and atherosclerotic plaques, where they primarily differentiate into fibroblasts, SMCs, or remain in a stem-like state. Klf4 knockout specifically in AdvSca1-SM cells induced transition to a more collagen-enriched myofibroblast phenotype compared to WT mice. Additionally, Klf4 depletion drastically modified the phenotypes of non-AdvSca1-SM-derived cells, resulting in more contractile SMCs and atheroprotective macrophages. Functionally, overall plaque burden was not altered with Klf4 depletion, but multiple indices of plaque vulnerability were reduced. Collectively, these data support that modulating the AdvSca1-SM population confers increased protection from the development of unstable atherosclerotic plaques.

pathology↗

bioRxiv2023

A Rapid, Functional sgRNA Screening Method for Generating Murine RET and NTRK1 Fusion Oncogenes

CRISPR/Cas9 gene editing technology is an indispensable and powerful tool in the field of cancer biology. To conduct successful CRISPR-based experiments, it is crucial that sgRNAs generate their designed alterations. Here, we describe a simple and efficient sgRNA screening method for validating sgRNAs that generate oncogenic gene rearrangements. We used IL3-independence in Ba/F3 cells as an assay to identify sgRNA pairs that generate fusion oncogenes involving the Ret and Ntrk1 tyrosine kinases. We confirmed these rearrangements with PCR or RT-PCR as well as sequencing. Ba/F3 cells harboring Ret or Ntrk1 rearrangements acquired sensitivity to RET and TRK inhibitors, respectively. Adenoviruses encoding Cas9 and sgRNAs that catalyze the Kif5b-Ret and Trim24-Ret rearrangements were intratracheally instilled into mice and yielded lung adenocarcinomas. A cell line (TR.1) was established from a Trim24-Ret positive tumor that exhibited high in vitro sensitivity to RET-specific TKIs. Moreover, orthotopic transplantation of TR.1 cells into the left lung yielded well-defined tumors that shrank in response to LOXO-292 treatment. The method offers an efficient means to validate sgRNAs that successfully target their intended loci for the generation of novel murine oncogene-driven tumor models.

cancer biology↗

bioRxiv2022

Novel EGFR-Mutant Mouse Models of Lung Adenocarcinoma Reveal Adaptive Immunity Requirement for Durable Osimertinib Response

Lung cancers bearing oncogenically-mutated EGFR represent a significant fraction of lung adenocarcinomas (LUADs) for which EGFR-targeting tyrosine kinase inhibitors (TKIs) provide a highly effective therapeutic approach. However, these lung cancers eventually acquire resistance and undergo progression within a characteristically broad treatment duration range. Our previous study of EGFR mutant lung cancer biopsies highlighted the positive association of a TKI-induced interferon {gamma} transcriptional response with increased time to treatment progression. To test the hypothesis that host immunity contributes to the TKI response, we developed novel genetically-engineered mouse models of EGFR mutant lung cancer bearing exon 19 deletions (del19) or the L860R missense mutation. Both oncogenic EGFR mouse models developed multifocal LUADs from which transplantable cancer cell lines sensitive to the EGFR-specific TKIs, gefitinib and osimertinib, were derived. When propagated orthotopically in the left lungs of syngeneic C57BL/6 mice, deep and durable shrinkage of the cell line-derived tumors was observed in response to daily treatment with osimertinib. By contrast, orthotopic tumors propagated in immune deficient nu/nu mice exhibited modest tumor shrinkage followed by rapid progression on continuous osimertinib treatment. Importantly, osimertinib treatment significantly increased intratumoral CD3+ T cell content relative to diluent treatment. The findings provide strong evidence supporting the requirement for adaptive immunity in the durable therapeutic control of EGFR mutant lung cancer.

cancer biology↗

bioRxiv2022

Evaluation of KRASG12C Inhibitor Responses in Novel Murine KRASG12C Lung Cancer Cell Line Models

The KRAS(G12C) mutation is the most common genetic mutation in North American lung adenocarcinoma patients. Recently, direct inhibitors of the KRASG12C protein have been developed and demonstrate clinical response rates of 37-43%. Importantly, these agents fail to generate durable therapeutic responses with median progression-free survival of ~6.5 months. To provide models for further preclinical improvement of these inhibitors, we generated three novel murine KRASG12C-driven lung cancer cell lines. The co-occurring NRASQ61L mutation in KRASG12C-positive LLC cells was deleted and the KRASG12V allele in CMT167 cells was edited to KRASG12C with CRISPR/Cas9 methods. Also, a novel murine KRASG12C line, mKRC.1, was established from a tumor generated in a genetically-engineered mouse model. The three lines exhibit similar in vitro sensitivities to KRASG12C inhibitors (MRTX-1257, AMG-510), but distinct in vivo responses to MRTX-849 ranging from progressive growth with orthotopic LLC-NRAS KO tumors to marked shrinkage with mKRC.1 tumors. All three cell lines exhibited synergistic in vitro growth inhibition with MRTX-1257 and the SHP2 inhibitor, RMC-4550 and the MRTX-849/RMC-4550 combination yielded tumor shrinkage in orthotopic LLC-NRAS KO tumors propagated in syngeneic mice. Notably, this synergistic combination response was lost in athymic nu/nu mice, supporting a growing literature demonstrating a role for adaptive immunity in the response to this class of drugs. These new models of murine KRASG12C mutant lung cancer should prove valuable for identifying improved therapeutic combination strategies with KRASG12C inhibitors. Contribution to the Field StatementThe development of KRASG12C inhibitors has not impacted treatment of lung cancers bearing the KRASG12C mutation to the degree that tyrosine kinase inhibitors have changed the treatment outcomes for patients bearing oncogenic mutations in receptor tyrosine kinases. Thus, the field is now exploring combination strategies with KRASG12C inhibitors that may enhance their clinical benefit. Moreover, published findings indicate that host immunity contributes to efficacy of oncogene-directed inhibitors including KRASG12C inhibitors. Thus, these novel murine KRASG12C-driven lung cancer cell lines will provide valuable models for preclinical evaluation of novel drug combinations in immune competent hosts.

cancer biology↗

bioRxiv2022

The Tryptophan Metabolizing Enzyme Indoleamine 2,3-Dioxygenase 1 Regulates Polycystic Kidney Disease Progression

Autosomal dominant polycystic kidney disease (ADPKD), the most common monogenic nephropathy, is characterized by phenotypic variability exceeding genic effects. Dysregulated metabolism and immune cell function are key disease modulators. The tryptophan metabolites, kynurenines, produced through IDO1, are known immunomodulators. Here, we study the role of tryptophan metabolism in PKD using an orthologous disease model (C57Bl/6J Pkd1RC/RC). We found elevated kynurenine and IDO1 levels in Pkd1RC/RC kidneys versus wildtype. Further, IDO1 levels were increased in ADPKD cell lines and patient cyst cells. Genetic Ido1 loss in Pkd1RC/RC animals resulted in reduced PKD severity as measured by %kidney weight/body weight and cystic index. Consistent with a immunomodulatory role of kynurenines, Pkd1RC/RC;Ido1-/- mice presented with significant changes in the cystic immune microenvironment (CME) versus controls. Of note, kidney macrophage numbers decreased and CD8+ T cell numbers increased, both known PKD modulators. Also, pharmacological IDO1 inhibition using a tryptophan analog in Pkd1RC/RC animals resulted in less severe PKD versus controls with similar changes in the CME as in the genetic model. Together, our data suggest that tryptophan metabolism is dysregulated in ADPKD and that its inhibition results in changes to the CME and slows disease progression, making IDO1 a novel therapeutic target for ADPKD.

molecular biology↗

bioRxiv2022

Immune Checkpoint Activity Regulates Polycystic Kidney Disease Progression

Innate and adaptive immune cells modulate Autosomal Dominant Polycystic Kidney Disease (ADPKD) severity, a common kidney disease with inadequate treatment options. ADPKD shares parallels with cancer where immune checkpoint inhibitors have been shown to reactivate CD8+ T cells and slow tumor growth. We have shown that, in PKD, CD8+ T cell loss worsens disease. This study used orthologous early-onset and adult-onset ADPKD models (Pkd1 p.R3277C) to evaluate the role of immune checkpoints in PKD. Flow cytometry of kidney cells showed increased levels of PD-1 on CD8+ T cells and PD-L1 on macrophages and epithelial cells in Pkd1RC/RC mice versus wildtypes, paralleling disease severity. PD-L1 was also upregulated in ADPKD human cells and patient kidney tissue versus controls. Genetic PD-L1 loss or treatment with an anti-PD-1 antibody did not impact PKD severity in early-onset or adult-onset ADPKD models. However, treatment with anti-PD-1 plus anti-CTLA-4, blocking two immune checkpoints, improved PKD outcomes in adult-onset ADPKD mice; neither monotherapy altered PKD. Combination therapy resulted in increased kidney CD8+ T cell numbers/activation and decreased kidney regulatory T cell numbers. Together, our data suggests that immune checkpoint activation is an important feature of and potential novel therapeutic target in ADPKD.

immunology↗

bioRxiv2022

Adaptive immunity is required for durable responses to alectinib in murine models of EML4-ALK lung cancer

PurposeLung cancers bearing oncogenic EML4-ALK fusions respond to targeted tyrosine kinase inhibitors (TKIs; e.g. alectinib), with variation in the degree of shrinkage and duration of treatment (DOT). We previously demonstrated a positive association of a TKI-induced interferon gamma (IFN{gamma}) transcriptional response with DOT in EGFR-mutant lung cancers. Herein, we used murine models of EML4-ALK lung cancer to test a role for host immunity in the therapeutic response to alectinib. Experimental DesignThree murine EML4-ALK cell lines (EA1, EA2, EA3) were implanted orthotopically into the lungs of immunocompetent and immunodeficient mice and treated with alectinib. Tumor volumes were serially measured by CT. Immune cell content was measured by flow cytometry, multispectral immunofluorescence and CyTOF. Transcriptional responses to alectinib were assessed by RNAseq and secreted chemokines were measured by ELISA. ResultsAll cell lines were sensitive to alectinib in vitro. EA1 and EA3 tumors retained residual disease that rapidly progressed upon termination of treatment while EA2 tumors were eliminated by TKI treatment. Alectinib induced inflammatory transcriptional programs and multiple chemokines in all cell lines while untreated tumors exhibited distinct baseline chemokine expression patterns and content of CD8+ T cells and myeloid subsets. When propagated in immune-deficient mice, all three cell line-derived lung tumor models exhibited significant shrinkage followed by prompt progression despite continuous alectinib treatment. ConclusionsThe findings support an hypothesis that host and TKI-stimulated production of chemokines by tumor cells promotes functional engagement of adaptive immune cells within the tumor microenvironment that enhances the durability and depth of TKI response. Statement of Translational RelevancePatients with metastatic lung cancer harboring ALK fusions are treated with targeted tyrosine kinase inhibitors (TKI) in the first line setting. Despite bearing the same driver oncogene, patients experience a range of tumor burden reduction and variable amounts of residual disease. Residual disease burden associates with patient survival and contributes to the emergence of drug resistance yielding treatment failure. The factors mediating this differential response to TKI and residual disease are incompletely understood. Our group has developed a panel of murine ALK driven lung cancer cell lines that reproducibly show differences in the depth and duration of response when implanted into immunocompetent mice. Data using this model indicate that the presence of CD8+ T cells is a major contributor to the depth and duration of response. These models will be critical in developing rational combination therapies to augment the immune microenvironment engagement along with TKIs to improve outcomes for these patients.

cancer biology↗

bioRxiv2020

Cancer Cell Intrinsic Expression of MHCII Regulates the Immune Microenvironment and Response to Anti-PD-1 Therapy in Lung Adenocarcinoma

MHC class II (MHCII) expression is usually restricted to antigen presenting cells, but can be expressed by cancer cells. We examined the effect of cancer cell-intrinsic MHC class II (csMHCII) expression in lung adenocarcinoma on T cell recruitment to tumors and response to anti-PD-1 therapy. The functional significance of altering csMHCII expression was explored using two orthotopic immunocompetent murine models of non-small cell lung cancer: CMT167 (CMT) and Lewis Lung Carcinoma (LLC). We previously showed that CMT167 tumors are eradicated by anti-PD1 therapy, while LLC tumors are resistant. RNA-seq analysis of cancer cells recovered from tumors revealed that csMHCII correlated with response to anti-PD1 therapy, with immunotherapy-sensitive CMT167 cells being csMHCII positive, while resistant LLC cells were csMHCII negative. To test the functional effects of csMHCII, MHCII expression was altered on the cancer cells through loss- and gain-of-function of CIITA, a master regulator of the MHCII pathway. Loss of CIITA in CMT167 decreased csMHCII, and converted tumors from anti-PD-1-sensitive to anti-PD-1-resistant. This was associated with decreased T cell infiltration, lower levels of Th1 cytokines, increased B cell number and decreased macrophage recruitment. Conversely, overexpression of CIITA in LLC cells resulted in csMHCII in vitro and in vivo. Enforced expression of CIITA increased T cell infiltration and sensitized tumors to anti-PD-1 therapy. csMHCII expression was also examined in a subset of surgically resected human lung adenocarcinomas by multispectral imaging, provided a survival benefit and positively correlated with T cell infiltration. These studies demonstrate a functional role for csMHCII in regulating T cell infiltration and sensitivity to anti-PD-1.

cancer biology↗

bioRxiv2019

Tumor-Intrinsic Response to IFNgamma Shapes the Tumor Microenvironment and Anti-PD-1 Response in NSCLC

Targeting PD-1/ PD-L1 is only effective in ~20% of lung cancer patients, but determinants of this response are poorly defined. We previously observed differential responses of two murine K-Ras lung cancer cell lines to anti-PD-1 therapy: CMT167 tumors were eliminated while LLC tumors were resistant. The goal of this study was to define mechanism(s) mediating this difference. RNA-Seq analysis of cancer cells recovered from lung tumors revealed that CMT167 cells induced an IFN{gamma} signature that was absent in LLC cells. Silencing Ifngr1 in CMT167 resulted in tumors resistant to IFN{gamma} and anti-PD-1 therapy. Conversely, LLC cells had high basal expression of Socs1, an inhibitor of IFN{gamma}. Silencing Socs1 increased response to IFN{gamma} in vitro and sensitized tumors to anti-PD-1. This was associated with a reshaped TME, characterized by enhanced T cell infiltration and enrichment of PD-L1 high myeloid cells. These studies demonstrate that targeted enhancement of tumor-intrinsic IFN{gamma} signaling can induce of cascade of changes associated with increased therapeutic vulnerability. SummaryMechanisms regulating response to anti-PD-1 therapy in lung cancer are not well defined. This study, using orthotopic immunocompetent mouse models of lung cancer, demonstrates that intrinsic sensitivity of cancer cells to IFN{gamma} determines anti-PD-1 responsiveness through alterations in the tumor microenvironment.

cancer biology↗