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The majority of fatalities thus far in the COVID-19 pandemic have been attributed to pneumonia. As expected, the fatality rate reported in China is higher in people with chronic pulmonary disease (6.3%) and those who have cancer (5.6%). According to the American College of Cardiology Clinical Bulletin "COVID-19 Clinical Guidance for the CV Care Team", there is a significantly higher fatality rate in people who are elderly (8.0% 70-79 years; 14.8% ≥80 years), diabetic (7.3%), hypertensive (6.0%), or have known cardiovascular disease (CVD) (10.5%). We propose a biological reason for the higher mortality risk in these populations that is apparent. We further present a set of pathophysiological reasons for the heightened danger that could lead to therapies for enhanced management and prevention.
Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.

Bronchopulmonary dysplasia (BPD) is a leading complication of preterm birth that affects infants born in the saccular stage of lung development at <32 weeks of gestation. Although the mechanisms driving BPD remain uncertain, exposure to hyperoxia is thought to contribute to disease pathogenesis. To determine the effects of hyperoxia on epithelial-mesenchymal interactions and to define the mediators of activated Wnt/β-catenin signaling after hyperoxia injury. Three hyperoxia models were used: A three-dimensional organotypic coculture using primary human lung cells, precision-cut lung slices (PCLS), and a murine hyperoxia model. Comparisons of normoxia- and hyperoxia-exposed samples were made by real-time quantitative PCR, RNA hybridization, quantitative confocal microscopy, and lung morphometry. Examination of an array of Wnt ligands in the three-dimensional organotypic coculture revealed increased mesenchymal expression of . Inhibition of Wnt5A abrogated the BPD transcriptomic phenotype induced by hyperoxia. In the PCLS model, Wnt5A inhibition improved alveolarization following hyperoxia exposure, and treatment with recombinant Wnt5a reproduced features of the BPD phenotype in PCLS cultured in normoxic conditions. Chemical inhibition of NF-κB with BAY11-7082 reduced expression in the PCLS hyperoxia model and mouse hyperoxia model, with improved alveolarization in the PCLS model. Increased mesenchymal Wnt5A during saccular-stage hyperoxia injury contributes to the impaired alveolarization and septal thickening observed in BPD. Precise targeting of Wnt5A may represent a potential therapeutic strategy for the treatment of BPD.

The outcomes of patients with SCLC have not yet been substantially impacted by the revolution in precision oncology, primarily owing to a paucity of genetic alterations in actionable driver oncogenes. Nevertheless, systemic therapies that include immunotherapy are beginning to show promise in the clinic. Although, these results are encouraging, many patients do not respond to, or rapidly recur after, current regimens, necessitating alternative or complementary therapeutic strategies. In this review, we discuss ongoing investigations into the pathobiology of this recalcitrant cancer and the therapeutic vulnerabilities that are exposed by the disease state. Included within this discussion, is a snapshot of the current biomarker and clinical trial landscapes for SCLC. Finally, we identify key knowledge gaps that should be addressed to advance the field in pursuit of reduced SCLC mortality. This review largely summarizes work presented at the Third Biennial International Association for the Study of Lung Cancer SCLC Meeting.
Copyright © 2020 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

Increased endothelial permeability is central to the pathogenesis of sepsis and leads to organ dysfunction and death but the endogenous mechanisms that drive increased endothelial permeability are not completely understood. We previously reported that cell-free hemoglobin (CFH), elevated in 80% of patients with sepsis, increases lung microvascular permeability in an ex vivo human lung model and cultured endothelial cells. In this study, we augmented a murine model of polymicrobial sepsis with elevated circulating CFH to test the hypothesis that CFH increases microvascular endothelial permeability by inducing endothelial apoptosis. Mice were treated with an intraperitoneal injection of cecal slurry with or without a single intravenous injection of CFH. Severity of illness, mortality, systemic and lung inflammation, endothelial injury and dysfunction and lung apoptosis were measured at selected time points. We found that CFH added to CS increased sepsis mortality, plasma inflammatory cytokines as well as lung apoptosis, edema and inflammation without affecting large vessel reactivity or vascular injury marker concentrations. These results suggest that CFH is an endogenous mediator of increased endothelial permeability and apoptosis in sepsis and may be a promising therapeutic target.

Integrins, the extracellular matrix receptors that facilitate cell adhesion and migration, are necessary for organ morphogenesis; however, their role in maintaining adult tissue homeostasis is poorly understood. To define the functional importance of β1 integrin in adult mouse lung, we deleted it after completion of development in type 2 alveolar epithelial cells (AECs). Aged β1 integrin-deficient mice exhibited chronic obstructive pulmonary disease-like (COPD-like) pathology characterized by emphysema, lymphoid aggregates, and increased macrophage infiltration. These histopathological abnormalities were preceded by β1 integrin-deficient AEC dysfunction such as excessive ROS production and upregulation of NF-κB-dependent chemokines, including CCL2. Genetic deletion of the CCL2 receptor, Ccr2, in mice with β1 integrin-deficient type 2 AECs impaired recruitment of monocyte-derived macrophages and resulted in accelerated inflammation and severe premature emphysematous destruction. The lungs exhibited reduced AEC efferocytosis and excessive numbers of inflamed type 2 AECs, demonstrating the requirement for recruited monocytes/macrophages in limiting lung injury and remodeling in the setting of a chronically inflamed epithelium. These studies support a critical role for β1 integrin in alveolar homeostasis in the adult lung.

Adopting a systems approach, we devise a general workflow to define actionable subtypes in human cancers. Applied to small cell lung cancer (SCLC), the workflow identifies four subtypes based on global gene expression patterns and ontologies. Three correspond to known subtypes (SCLC-A, SCLC-N, and SCLC-Y), while the fourth is a previously undescribed ASCL1+ neuroendocrine variant (NEv2, or SCLC-A2). Tumor deconvolution with subtype gene signatures shows that all of the subtypes are detectable in varying proportions in human and mouse tumors. To understand how multiple stable subtypes can arise within a tumor, we infer a network of transcription factors and develop BooleaBayes, a minimally-constrained Boolean rule-fitting approach. In silico perturbations of the network identify master regulators and destabilizers of its attractors. Specific to NEv2, BooleaBayes predicts ELF3 and NR0B1 as master regulators of the subtype, and TCF3 as a master destabilizer. Since the four subtypes exhibit differential drug sensitivity, with NEv2 consistently least sensitive, these findings may lead to actionable therapeutic strategies that consider SCLC intratumoral heterogeneity. Our systems-level approach should generalize to other cancer types.

INTRODUCTION - Despite initial effectiveness of ALK receptor tyrosine kinase inhibitors (TKIs) in patients with ALK+ NSCLC, therapeutic resistance will ultimately develop. Serial tracking of genetic alterations detected in circulating tumor DNA (ctDNA) can be an informative strategy to identify response and resistance. This study evaluated the utility of analyzing ctDNA as a function of response to ensartinib, a potent second-generation ALK TKI.
METHODS - Pre-treatment plasma was collected from 76 patients with ALK+ NSCLC who were ALK TKI-naive or had received prior ALK TKI, and analyzed for specific genetic alterations. Longitudinal plasma samples were analyzed from a subset (n = 11) of patients. Analysis of pre-treatment tumor biopsy specimens from 22 patients was compared with plasma.
RESULTS - Disease-associated genetic alterations were detected in 74% (56 of 76) of patients, the most common being EML4-ALK. Concordance of ALK fusion between plasma and tissue was 91% (20 of 22 blood and tissue samples). Twenty-four ALK kinase domain mutations were detected in 15 patients, all had previously received an ALK TKI; G1269A was the most prevalent (4 of 24). Patients with a detectable EML4-ALK variant 1 (V1) fusion had improved response (9 of 17 patients; 53%) to ensartinib compared to patients with EML4-ALK V3 fusion (one of seven patients; 14%). Serial changes in ALK alterations were observed during therapy.
CONCLUSIONS - Clinical utility of ctDNA was shown, both at pre-treatment by identifying a potential subgroup of ALK+ NSCLC patients who may derive more benefit from ensartinib and longitudinally by tracking resistance. Prospective application of this technology may translate to improved outcomes for NSCLC patients treated with ALK TKIs.
Copyright © 2019 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.

BACKGROUND - Approximately 10% of patients with SCLC develop a paraneoplastic syndrome (PNS). Neurologic PNS are thought to improve prognosis, which we hypothesized is related to increased tumor-infiltrating lymphocytes and immune recognition.
METHODS - We queried 2,512,042 medical records from a single institution to identify patients who have SCLC with and without PNS and performed manual, retrospective chart review. We then performed multiplexed fluorescence immunohistochemistry and automated quantitative analysis (AQUA Technology) on tumors to assess CD3, CD4, and CD8 T cell infiltrates and programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) interactions. T cell infiltrates and PD-1/PD-L1 interaction scores were compared among patients with neurologic PNS, endocrinologic PNS, and a control group without PNS. Clinical outcomes were analyzed using the Kaplan-Meier method and Cox proportional hazards models.
RESULTS - We evaluated 145 SCLC patients: 55 with PNS (25 neurologic and 30 endocrinologic) and 90 controls. Patients with neurologic PNS experienced improved overall survival compared to patients with endocrinologic PNS and controls (median overall survival of 24 months versus 12 months versus 13 months, respectively). Of the 145 patients, we identified tumor tissue from 34 patients that was adequate for AQUA analysis. Among 37 specimens from these 34 patients, patients with neurologic PNS had increased T cell infiltrates (p = 0.033) and PD-1/PD-L1 interaction (p = 0.014) compared to tumors from patients with endocrinologic PNS or controls.
CONCLUSIONS - Tumor tissue from patients with SCLC with neurologic PNS showed increased tumor-infiltrating lymphocytes and PD-1/PD-L1 interaction consistent with an inflamed tumor microenvironment.
Copyright © 2019 International Association for the Study of Lung Cancer. Published by Elsevier Inc. All rights reserved.