Publications by authors named "John T Poirier"

Article Synopsis
  • Interferons (IFNs) are important for how our bodies respond to viruses, and this study used CRISPR to find human genes affecting SARS-CoV-2 infection with and without IFN.
  • The research identified 28 key genes linked to COVID-19, especially those involving the IFN pathway, including PLSCR1, which can limit virus entry without needing IFN.
  • PLSCR1’s ability to block SARS-CoV-2 was reduced by the overexpression of TMPRSS2, and some virus variants have evolved to bypass PLSCR1’s defense, suggesting ongoing challenges in controlling the virus.
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Retrons are a retroelement class found in diverse prokaryotes that can be adapted to augment CRISPR-Cas9 genome engineering technology to efficiently rewrite short stretches of genetic information in bacteria and yeast; however, efficiency in human cells has been limited by unknown factors. We identified non-coding RNA (ncRNA) instability and impaired Cas9 activity as major contributors to poor retron editor efficiency. We re-engineered the Eco1 ncRNA to incorporate an exoribonuclease-resistant RNA pseudoknot from the Zika virus 3' UTR and devised an RNA processing strategy using Csy4 ribonuclease to liberate the sgRNA and ncRNA.

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Background: Delta-like ligand 3 (DLL3) is aberrantly expressed on the surface of small-cell lung cancer (SCLC) and neuroendocrine prostate cancer cells. We assessed the safety and feasibility of the DLL3-targeted imaging tracer [Zr]Zr-DFO-SC16.56 (composed of the anti-DLL3 antibody SC16.

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Loss-of-function mutations in frequently occur in lung cancer and are associated with poor prognosis and resistance to standard of care treatment, highlighting the need for the development of targeted therapies. We previously showed that mutant tumors consume glutamine to support the metabolic rewiring associated with NRF2-dependent antioxidant production. Here, using preclinical patient-derived xenograft models and antigenic orthotopic lung cancer models, we show that the glutamine antagonist prodrug DRP-104 impairs the growth of mutant tumors.

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Background: Delta-like ligand 3 (DLL3) is aberrantly expressed on the cell surface in many neuroendocrine cancers including small cell lung cancer (SCLC) and neuroendocrine prostate cancer (NEPC). Several therapeutic agents targeting DLL3 are in active clinical development. Molecular imaging of DLL3 would enable non-invasive diagnostic assessment to inform the use of DLL3-targeting therapeutics or to assess disease treatment response.

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Lung cancer treatment has benefited greatly through advancements in immunotherapies. However, immunotherapy often fails in patients with specific mutations like KEAP1, which are frequently found in lung adenocarcinoma. We established an antigenic lung cancer model and used it to explore how Keap1 mutations remodel the tumor immune microenvironment.

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Article Synopsis
  • Loss-of-function mutations in lung cancer lead to treatment resistance, emphasizing the importance of targeted therapies.
  • Research has shown that the glutamine antagonist DRP-104 can slow the growth of mutant tumors by inhibiting nucleotide synthesis and boosting immune responses.
  • DRP-104 also reverses T cell exhaustion, enhancing CD4 and CD8 T cell function and improving responses to anti-PD1 therapies, suggesting a promising treatment future for lung cancer patients with these mutations.
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Introduction: A small percentage of patients with SCLC experience durable responses to immune checkpoint blockade (ICB). Defining determinants of immune response may nominate strategies to broaden the efficacy of immunotherapy in patients with SCLC. Prior studies have been limited by small numbers or concomitant chemotherapy administration.

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Unlabelled: LKB1/STK11 is a serine/threonine kinase that plays a major role in controlling cell metabolism, resulting in potential therapeutic vulnerabilities in LKB1-mutant cancers. Here, we identify the NAD degrading ectoenzyme, CD38, as a new target in LKB1-mutant NSCLC. Metabolic profiling of genetically engineered mouse models (GEMMs) revealed that LKB1 mutant lung cancers have a striking increase in ADP-ribose, a breakdown product of the critical redox co-factor, NAD .

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Lung squamous cell carcinoma (LUSC) represents a major subtype of lung cancer with limited treatment options. KMT2D is one of the most frequently mutated genes in LUSC (>20%), and yet its role in LUSC oncogenesis remains unknown. Here, we identify KMT2D as a key regulator of LUSC tumorigenesis wherein Kmt2d deletion transforms lung basal cell organoids to LUSC.

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Background: Diffuse pleural mesothelioma (DPM) is an aggressive malignancy that, despite recent treatment advances, has unacceptably poor outcomes. Therapeutic research in DPM is inhibited by a paucity of preclinical models that faithfully recapitulate the human disease.

Methods: We established 22 patient-derived xenografts (PDX) from 22 patients with DPM and performed multi-omic analyses to deconvolute the mutational landscapes, global expression profiles, and molecular subtypes of these PDX models and compared features to those of the matched primary patient tumors.

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We report a protocol for obtaining high-quality single-cell transcriptomics data from human lung biospecimens acquired from core needle biopsies, fine-needle aspirates, surgical resection, and pleural effusions. The protocol relies upon the brief mechanical and enzymatic disruption of tissue, enrichment of live cells by fluorescence-activated cell sorting (FACS), and droplet-based single-cell RNA sequencing (scRNA-seq). The protocol also details a procedure for analyzing the scRNA-seq data.

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Small cell lung cancer (SCLC) is characterized by morphologic, epigenetic and transcriptomic heterogeneity. Subtypes based upon predominant transcription factor expression have been defined that, in mouse models and cell lines, exhibit potential differential therapeutic vulnerabilities, with epigenetically distinct SCLC subtypes also described. The clinical relevance of these subtypes is unclear, due in part to challenges in obtaining tumor biopsies for reliable profiling.

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The microsomal triglyceride transfer protein (MTP) is essential for the secretion of apolipoprotein B (apoB)48- and apoB100-containing lipoproteins in the intestine and liver, respectively. Loss of function mutations in MTP cause abetalipoproteinemia. Heterologous cells are used to evaluate the function of MTP in apoB secretion to avoid background MTP activity in liver and intestine-derived cells.

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Neuroendocrine prostate cancer (NEPC) is a lethal subtype of prostate cancer with limited meaningful treatment options. NEPC lesions uniquely express delta-like ligand 3 (DLL3) on their cell surface. Taking advantage of DLL3 overexpression, we developed and evaluated lutetium-177 (Lu)-labeled DLL3-targeting antibody SC16 (Lu-DTPA-SC16) as a treatment for NEPC.

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Access to clinically relevant small cell lung cancer (SCLC) tissue is limited because surgical resection is rare in metastatic SCLC. Patient-derived xenografts (PDX) and circulating tumor cell-derived xenografts (CDX) have emerged as valuable tools to characterize SCLC. Here, we present a resource of 46 extensively annotated PDX/CDX models derived from 33 patients with SCLC.

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Treatment-induced neuroendocrine prostate cancer (NEPC) is a lethal subtype of castration-resistant prostate cancer. Using the Zr-labeled delta-like ligand 3 (DLL3) targeting antibody SC16 (Zr-desferrioxamine [DFO]-SC16), we have developed a PET agent to noninvasively identify the presence of DLL3-positive NEPC lesions. Quantitative polymerase chain reaction and immunohistochemistry were used to compare relative levels of androgen receptor (AR)-regulated markers and the NEPC marker DLL3 in a panel of prostate cancer cell lines.

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Purpose: Small cell lung cancer (SCLC) is an exceptionally lethal form of lung cancer with limited treatment options. Delta-like ligand 3 (DLL3) is an attractive therapeutic target as surface expression is almost exclusive to tumor cells.

Experimental Design: We radiolabeled the anti-DLL3 mAb SC16 with the therapeutic radioisotope, Lutetium-177.

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Zika virus (ZIKV) is a re-emerging flavivirus that has caused large-scale epidemics. Infection during pregnancy can lead to neurologic developmental abnormalities in children. There is no approved vaccine or therapy for ZIKV.

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Small cell lung cancer (SCLC) is an aggressive malignancy characterized by early metastasis and extreme lethality. The backbone of SCLC treatment over the past several decades has been platinum-based doublet chemotherapy, with the recent addition of immunotherapy providing modest benefits in a subset of patients. However, nearly all patients treated with systemic therapy quickly develop resistant disease, and there is an absence of effective therapies for recurrent and progressive disease.

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Article Synopsis
  • The study explores the role of the mitogen-activated protein kinase (MAPK) pathway in small cell lung cancer (SCLC), highlighting its unique behavior compared to non-small cell lung cancer.
  • It reveals that the most common subtype, SCLC-A, is sensitive to MAPK activation, which induces cell-cycle arrest and senescence.
  • The research also identifies significant changes in regulatory pathways upon MAPK activation, suggesting that SCLC has complex signaling networks and subtype-specific vulnerabilities that could be targeted for treatment.
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Small cell lung cancer (SCLC) is an aggressive malignancy that includes subtypes defined by differential expression of ASCL1, NEUROD1, and POU2F3 (SCLC-A, -N, and -P, respectively). To define the heterogeneity of tumors and their associated microenvironments across subtypes, we sequenced 155,098 transcriptomes from 21 human biospecimens, including 54,523 SCLC transcriptomes. We observe greater tumor diversity in SCLC than lung adenocarcinoma, driven by canonical, intermediate, and admixed subtypes.

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Molecular virology tools are critical for basic studies of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and for developing new therapeutics. Experimental systems that do not rely on viruses capable of spread are needed for potential use in lower-containment settings. In this work, we use a yeast-based reverse genetics system to develop spike-deleted SARS-CoV-2 self-replicating RNAs.

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Substantial progress has been made in understanding how tumors escape immune surveillance. However, few measures to counteract tumor immune evasion have been developed. Suppression of tumor antigen expression is a common adaptive mechanism that cancers use to evade detection and destruction by the immune system.

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Unlabelled: Small cell lung cancer (SCLC) has limited therapeutic options and an exceptionally poor prognosis. Understanding the oncogenic drivers of SCLC may help define novel therapeutic targets. Recurrent genomic rearrangements have been identified in SCLC, most notably an in-frame gene fusion between RLF and MYCL found in up to 7% of the predominant ASCL1-expressing subtype.

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