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Persistent inflammation driven by cytokines such as type-one interferon (IFN-I) can cause immunosuppression. We show that administration of the Janus kinase 1 (JAK1) inhibitor itacitinib after anti-PD-1 (programmed cell death protein 1) immunotherapy improves immune function and antitumor responses in mice and results in high response rates (67%) in a phase 2 clinical trial for metastatic non-small cell lung cancer. Patients who failed to respond to initial anti-PD-1 immunotherapy but responded after addition of itacitinib had multiple features of poor immune function to anti-PD-1 alone that improved after JAK inhibition. Itacitinib promoted CD8 T cell plasticity and therapeutic responses of exhausted and effector memory-like T cell clonotypes. Patients with persistent inflammation refractory to itacitinib showed progressive CD8 T cell terminal differentiation and progressive disease. Thus, JAK inhibition may improve the efficacy of anti-PD-1 immunotherapy by pivoting T cell differentiation dynamics.
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Linfocitos T CD8-positivos , Carcinoma de Pulmón de Células no Pequeñas , Inhibidores de Puntos de Control Inmunológico , Janus Quinasa 1 , Inhibidores de las Cinasas Janus , Neoplasias Pulmonares , Receptor de Muerte Celular Programada 1 , Animales , Femenino , Humanos , Ratones , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Carcinoma de Pulmón de Células no Pequeñas/terapia , Linfocitos T CD8-positivos/inmunología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunoterapia/métodos , Janus Quinasa 1/antagonistas & inhibidores , Inhibidores de las Cinasas Janus/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/terapia , Receptor de Muerte Celular Programada 1/antagonistas & inhibidoresRESUMEN
Introduction: Patients with oligometastatic NSCLC benefit from locally ablative therapies (LAT); the role of adjuvant systemic therapies, however, remains less clear. In a single-arm, phase II clinical trial, we found that patients with oligometastatic NSCLC treated with a year of pembrolizumab after LAT had superior progression-free survival (PFS) compared with a historical control cohort. Herein, we present long-term follow-up on PFS and overall survival (OS). Methods: From February 1, 2015, to September 30, 2017, 45 patients with synchronous or metachronous oligometastatic (≤4 metastatic sites) NSCLC treated with LAT to all sites received adjuvant pembrolizumab every 21 days for up to 16 cycles. The primary efficacy end point was PFS from the start of pembrolizumab. Secondary end points included OS and safety. Median duration of follow-up was 66 months, and data cutoff was December 1, 2022. Results: A total of 45 patients were enrolled and treated with pembrolizumab after LAT (median age, 64 y [range, 46-82]; 21 women [47%]; 31 with a solitary oligometastatic site [69%]). At the data cutoff, 32 patients had progressive disease, 19 patients had died, and 13 patients had no evidence of relapse. Median PFS was 19.7 months (95% confidence interval: 7.6-31.7 mo); median OS was not reached (95% confidence interval: 37.7 mo-not reached). OS at 5 years was 60.0% (SE, 7.4%). Metachronous oligometastatic disease was associated with improved OS and PFS through Cox proportional hazard models. Conclusions: Pembrolizumab after LAT for oligometastatic NSCLC results in promising PFS and OS with a tolerable safety profile.
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INTRODUCTION: The patterns of failure (POF) for metastatic non-small-cell lung cancer (mNSCLC) treated with immunotherapy are not well established. METHODS: We conducted a retrospective cohort study of mNSCLC that received first-line pembrolizumab with or without chemotherapy at a single academic center from 2015 to 2021. We defined POF with 2 classifications: 1) local, regional, or distant failure, or 2) failure in existing lesions, new lesions, or a combination. Oligoprogression was defined as disease progression (PD) in ≤3 sites of failure. Overall survival (OS) was measured via Kaplan-Meier and modelled with Cox regression. RESULTS: Of 298 patients identified, 198 had PD. Using POF classification 1, most failures were distant (43.9%) or a combination of locoregional and distant (34.4%). For POF classification 2, failures occurred in a combination of new and existing lesions (45.0%), existing lesions alone (33.3%), or in new lesions only (21.7%). Oligoprogression occurred in 39.9% (n = 79) cases. Median OS was higher in the following: PD in existing lesions vs. new or new + existing lesions (28.7 vs. 20.2 vs. 13.9 months, P < .001) and oligoprogression vs. polyprogression (35.1 vs. 12.2 months, P < .001). In oligoprogression, median OS was better for those who received radiation to all sites of PD (62.2 months) than for those who changed systemic therapy (22.9 months, P = .007). On multivariable analysis, radiation for oligoprogression (HR 0.35, 95% CI: 0.20-0.62, P < .001) was associated with improved OS. CONCLUSIONS: In mNSCLC treated with pembrolizumab, oligoprogression is relatively common. Randomized data are needed to define the benefits of radiation in oligoprogressive mNSCLC.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/patología , Estudios Retrospectivos , Anticuerpos Monoclonales HumanizadosRESUMEN
PURPOSE: People with cancer are at increased risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. ASCO's COVID-19 registry promotes systematic data collection across US oncology practices. METHODS: Participating practices enter data on patients with SARS-CoV-2 infection in cancer treatment. In this analysis, we focus on all patients with hematologic or regional or metastatic solid tumor malignancies. Primary outcomes are 30- and 90-day mortality rates and change over time. RESULTS: Thirty-eight practices provided data for 453 patients from April to October 2020. Sixty-two percent had regional or metastatic solid tumors. Median age was 64 years. Forty-three percent were current or previous cigarette users. Patients with B-cell malignancies age 61-70 years had twice mortality risk (hazard ratio = 2.1 [95% CI, 1.3 to 3.3]) and those age > 70 years had 4.5 times mortality risk (95% CI, 1.8 to 11.1) compared with patients age ≤ 60 years. Association between survival and age was not significant in patients with metastatic solid tumors (P = .12). Tobacco users had 30-day mortality estimate of 21% compared with 11% for never users (log-rank P = .005). Patients diagnosed with SARS-CoV-2 before June 2020 had 30-day mortality rate of 20% (95% CI, 14% to 25%) compared with 13% (8% to 18%) for those diagnosed in or after June 2020 (P = .08). The 90-day mortality rate for pre-June patients was 28% (21% to 34%) compared with 21% (13% to 28%; P = .20). CONCLUSION: Older patients with B-cell malignancies were at increased risk for death (unlike older patients with metastatic solid tumors), as were all patients with cancer who smoke tobacco. Diagnosis of SARS-CoV-2 later in 2020 was associated with more favorable 30- and 90-day mortality, likely related to more asymptomatic cases and improved clinical management.
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COVID-19 , Neoplasias , Anciano , COVID-19/complicaciones , COVID-19/terapia , Humanos , Persona de Mediana Edad , Neoplasias/complicaciones , Neoplasias/epidemiología , Neoplasias/terapia , Modelos de Riesgos Proporcionales , Sistema de Registros , SARS-CoV-2 , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Patients with metastatic non-small-cell lung cancer (mNSCLC) and untreated brain metastases (BM) have been excluded from most trials of immune checkpoint inhibitors (ICIs). Real-world evidence on efficacy and survival outcomes of ICIs in patients with BM is limited. PATIENTS AND METHODS: We conducted a single-center retrospective study of patients with mNSCLC treated with pembrolizumab with or without chemotherapy and compared progression-free survival (PFS) and overall survival (OS) between patients with and without BM using Kaplan-Meier and Cox methodology. We also characterized systemic and intracranial objective response rate (ORR) and treatment details, including timing of cranial irradiation. RESULTS: Between Augutst 2013 and December 2018, 570 patients with mNSCLC treated with pembrolizumab-based therapy were analyzed. Of 126 (22.1%) patients with BM, 96 (76.2%) had treated BM (local therapy prior to pembrolizumab), and 30 (23.8%) had untreated BM. Of patients with untreated BM, 17 (56.7%) underwent radiation within 30 days after pembrolizumab initiation. In the remaining 13 (43.3%) treated with pembrolizumab-based therapy alone, intracranial ORR was 36.4%. Patients with and without BM did not have significantly different systemic ORR (27.8% vs. 29.7%; P = .671), PFS (mPFS 9.2 vs. 7.7 months; P = .609), or OS (mOS 18.0 vs. 18.7 months; P = .966). Factors associated with improved survival on Cox analysis included female gender, performance status, adenocarcinoma histology, and first-line therapy. CONCLUSIONS: Patients with BM did not have inferior survival to patients without BM after treatment with pembrolizumab-based therapy. In the current era, BM may not automatically confer inferior survival, and should not exclude patients from receiving pembrolizumab-based therapy.
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Adenocarcinoma del Pulmón/mortalidad , Anticuerpos Monoclonales Humanizados/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Encefálicas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Células Escamosas/mortalidad , Neoplasias Pulmonares/mortalidad , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/patología , Anciano , Antineoplásicos Inmunológicos/uso terapéutico , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/secundario , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/patología , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
BACKGROUND: Limited data exist on the role of alterations in HLA Class I antigen processing and presentation machinery in mediating response to immune checkpoint blockade (ICB). METHODS: This retrospective cohort study analyzed transcriptional profiles from pre-treatment tumor samples of 51 chemotherapy-refractory advanced non-small cell lung cancer (NSCLC) patients and two independent melanoma cohorts treated with ICB. An antigen processing machinery (APM) score was generated utilizing eight genes associated with APM (B2M, CALR, NLRC5, PSMB9, PSME1, PSME3, RFX5, and HSP90AB1). Associations were made for therapeutic response, progression-free survival (PFS) and overall survival (OS). RESULTS: In NSCLC, the APM score was significantly higher in responders compared with non-responders (p=0.0001). An APM score above the median value for the cohort was associated with improved PFS (HR 0.34 (0.18 to 0.64), p=0.001) and OS (HR 0.44 (0.23 to 0.83), p=0.006). The APM score was correlated with an inflammation score based on the established T-cell-inflamed resistance gene expression profile (Pearson's r=0.58, p<0.0001). However, the APM score better predicted response to ICB relative to the inflammation score with area under a receiving operating characteristics curve of 0.84 and 0.70 for PFS and OS, respectively. In a cohort of 14 high-risk resectable stage III/IV melanoma patients treated with neoadjuvant anti-PD1 ICB, a higher APM score was associated with improved disease-free survival (HR: 0.08 (0.01 to 0.50), p=0.0065). In an additional independent melanoma cohort of 27 metastatic patients treated with ICB, a higher APM score was associated with improved OS (HR 0.29 (0.09 to 0.89), p=0.044). CONCLUSION: Our data demonstrate that defects in antigen presentation may be an important feature in predicting outcomes to ICB in both lung cancer and melanoma.
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Presentación de Antígeno/inmunología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Melanoma/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/patología , Femenino , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Neoplasias Pulmonares/patología , Masculino , Melanoma/patología , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
OBJECTIVES: Treatment of non-small cell lung cancer (NSCLC) with immune checkpoint blockade (ICB) has resulted in striking clinical responses, but only in a subset of patients. The goal of this study was to evaluate transcriptional signatures previously reported in the literature in an independent cohort of NSCLC patients receiving ICB. MATERIALS AND METHODS: This retrospective study analyzed transcriptional profiles from pre-treatment tumor samples of 52 chemotherapy-refractory advanced NSCLC patients treated with anti-PD1/PD-L1 therapy. Gene signatures based on published reports were created and examined for their association with response to therapy and progression-free and overall survival (PFS, OS). RESULTS: Two signatures predicting response and outcomes were identified. One reflected the degree of immune infiltration and upregulation of interferon-gamma-induced genes. A second reflected the EMT status. Compared to those not responding to therapy, patients whose tumors responded to ICB had higher scores in an inflammatory gene signature (6.0⯱â¯2.9 vs -5.5⯱â¯3.4, pâ¯=â¯0.014) or a more epithelial phenotype (-1.7⯱â¯1.0 vs 2.1⯱â¯1.2, pâ¯=â¯0.016). Both signatures demonstrated a satisfactory predictive accuracy for response: AUC of 0.69 (95% CI: 0.54, 0.84) for the inflammatory and 0.70 (95% CI: 0.55, 0.85) for EMT signatures, respectively. A weighted score combining EMT and inflammatory signatures showed increased predictive value with AUC of 0.92 (95% CI: 0.85, 0.99). Kaplan-Meier curves for patients above and below the median combined score showed a significant separation for PFS and OS (all pâ¯<â¯0.01, log rank test). CONCLUSIONS: The EMT/Inflammation signature score may be useful in directing checkpoint inhibitor therapy in lung cancer and suggests that reversal of EMT might augment efficacy of ICB.
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Adenocarcinoma del Pulmón/patología , Antineoplásicos Inmunológicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/patología , Transición Epitelial-Mesenquimal/genética , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inflamación/genética , Neoplasias Pulmonares/patología , Adenocarcinoma del Pulmón/tratamiento farmacológico , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/inmunología , Biomarcadores de Tumor , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/inmunología , Transición Epitelial-Mesenquimal/efectos de los fármacos , Femenino , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Humanos , Inflamación/tratamiento farmacológico , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/inmunología , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
IMPORTANCE: Patients with oligometastatic non-small cell lung cancer (NSCLC) may benefit from locally ablative therapy (LAT) such as surgery or stereotactic radiotherapy. Prior studies were conducted before the advent of immunotherapy, and a strong biological rationale for the use of immunotherapy exists in a minimal residual disease state. OBJECTIVE: To evaluate whether the addition of pembrolizumab after LAT improves outcomes for patients with oligometastatic NSCLC. DESIGN, SETTING, AND PARTICIPANTS: This single-arm phase 2 trial of pembrolizumab therapy was performed from February 1, 2015, through September 30, 2017, at an academic referral cancer center. The 51 eligible patients enrolled had oligometastatic NSCLC (≤4 metastatic sites) and had completed LAT to all known sites of disease. Data were analyzed from February 1, 2015, to August 23, 2018. INTERVENTIONS: Within 4 to 12 weeks of completing LAT, patients began intravenous pembrolizumab therapy, 200 mg every 21 days, for 8 cycles, with provision to continue to 16 cycles in the absence of progressive disease or untoward toxic effects. MAIN OUTCOMES AND MEASURES: The 2 primary efficacy end points were progression-free survival (PFS) from the start of LAT (PFS-L), which preceded enrollment in the trial, and PFS from the start of pembrolizumab therapy (PFS-P). The study was powered for comparison with historical data on the first efficacy end point. Secondary outcomes included overall survival, safety, and quality of life as measured by the Functional Assessment of Cancer Therapy-Lung instrument. RESULTS: Of 51 patients enrolled, 45 (24 men [53%]; median age, 64 years [range, 46-82 years]) received pembrolizumab. At the time of analysis, 24 patients had progressive disease or had died. Median PFS-L was 19.1 months (95% CI, 9.4-28.7 months), significantly greater than the historical median of 6.6 months (P = .005). Median PFS-P was 18.7 months (95% CI, 10.1-27.1 months). Eleven patients died. Overall mean (SE) survival rate at 12 months was 90.9% (4.3%); at 24 months, 77.5% (6.7%). Neither programmed death ligand 1 expression nor CD8 T-cell tumor infiltration was associated with PFS-L. Pembrolizumab after LAT yielded no new safety signals and no reduction in quality of life. CONCLUSIONS AND RELEVANCE: Pembrolizumab after LAT for oligometastatic NSCLC appears to improve PFS with no reduction in quality of life. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02316002.
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PURPOSE: TP53 mutation (MT) in epidermal growth factor receptor (EGFR) -MT non-small cell lung cancer (NSCLC) is associated with poor response to targeted therapy; however, its impact on survival is not clearly established. PATIENTS AND METHODS: We performed an analysis of patients with stage IV EGFR MT NSCLC with available gene sequencing data. Associations between baseline characteristics; molecular profile, including TP53 MT; and survival outcomes were assessed. RESULTS: We identified 131 consecutive patients with EGFR MT; 81 (62%) had a TP53 MT, and 55 (42%) had other coexisting oncogenic MTs. Emergent EGFR T790M MT was observed in 42 patients (32%). Overall survival (OS) was longer for younger patients (P = .003), never smokers (P = .002), those with Eastern Cooperative Oncology Group performance status 0 to 1 (P = .004), and emergent T790M MT (P = .018). TP53 MT (P = .021) and other coexisting oncogenic MTs (P = 0.011) were associated with inferior OS. In a multivariable regression analysis adjusted for age, smoking, Eastern Cooperative Oncology Group performance status, and the presence of TP53 MT (P = .063) and other coexisting MTs (P = .064) did not achieve statistical significance. Patients with EGFR T790M/TP53 double MT had worse OS compared with patients with T790M MT alone (46.4 months v 82.9 months). In our series, five patients transformed to small-cell lung cancer (5.6%). All had TP53 MT. In four patients, allelic fraction of TP53 MT increased at the time of transformation. CONCLUSION: The presence of TP53 and other coexisting MTs in EGFR MT NSCLC were associated with inferior OS, including patients with emergent T790M MT. An increase in TP53 mutation allelic fraction may potentially be a useful clinical predictor of small-cell transformation.
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Mitochondrial membrane potential loss has severe bioenergetic consequences and contributes to many human diseases including myocardial infarction, stroke, cancer, and neurodegeneration. However, despite its prominence and importance in cellular energy production, the basic mechanism whereby the mitochondrial membrane potential is established remains unclear. Our studies elucidate that complex II-driven electron flow is the primary means by which the mitochondrial membrane is polarized under hypoxic conditions and that lack of the complex II substrate succinate resulted in reversible membrane potential loss that could be restored rapidly by succinate supplementation. Inhibition of mitochondrial complex I and F(0)F(1)-ATP synthase induced mitochondrial depolarization that was independent of the mitochondrial permeability transition pore, Bcl-2 (B-cell lymphoma 2) family proteins, or high amplitude swelling and could not be reversed by succinate. Importantly, succinate metabolism under hypoxic conditions restores membrane potential and ATP levels. Furthermore, a reliance on complex II-mediated electron flow allows cells from mitochondrial disease patients devoid of a functional complex I to maintain a mitochondrial membrane potential that conveys both a mitochondrial structure and the ability to sequester agonist-induced calcium similar to that of normal cells. This finding is important as it sets the stage for complex II functional preservation as an attractive therapy to maintain mitochondrial function during hypoxia.
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Calcio/fisiología , Complejo II de Transporte de Electrones/fisiología , Hipoxia , Potencial de la Membrana Mitocondrial , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Adenosina Trifosfato , Animales , Humanos , Ratones , Proteínas de Transporte de Membrana Mitocondrial , Poro de Transición de la Permeabilidad Mitocondrial , ATPasas de Translocación de Protón/fisiología , Ratas , Ácido Succínico/farmacologíaRESUMEN
Nitric oxide (NO) and other reactive nitrogen species target multiple sites in the mitochondria to influence cellular bioenergetics and survival. Kinetic imaging studies revealed that NO from either activated macrophages or donor compounds rapidly diffuses to the mitochondria, causing a dose-dependent progressive increase in NO-dependent DAF fluorescence, which corresponded to mitochondrial membrane potential loss and initiated alterations in cellular bioenergetics that ultimately led to necrotic cell death. Cellular dysfunction is mediated by an elevated 3-nitrotyrosine signature of the mitochondrial complex I subunit NDUFB8, which is vital for normal mitochondrial function as evidenced by selective knockdown via siRNA. Overexpression of mitochondrial superoxide dismutase substantially decreased NDUFB8 nitration and restored mitochondrial homeostasis. Further, treatment of cells with either necrostatin-1 or siRNA knockdown of RIP1 and RIP3 prevented NO-mediated necrosis. This work demonstrates that the interaction between NO and mitochondrially derived superoxide alters mitochondrial bioenergetics and cell function, thus providing a molecular mechanism for reactive oxygen and nitrogen species-mediated alterations in mitochondrial homeostasis.
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Complejo I de Transporte de Electrón/metabolismo , Endotelio Vascular/metabolismo , Fibroblastos/metabolismo , Macrófagos/metabolismo , Mitocondrias/metabolismo , Animales , Línea Celular , Complejo I de Transporte de Electrón/genética , Endotelio Vascular/efectos de los fármacos , Endotelio Vascular/patología , Fibroblastos/efectos de los fármacos , Fibroblastos/patología , Humanos , Imidazoles/farmacología , Indoles/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/patología , Potencial de la Membrana Mitocondrial , Ratones , Microscopía Fluorescente , Mitocondrias/efectos de los fármacos , Mitocondrias/genética , Necrosis/genética , Óxido Nítrico/metabolismo , Proteínas de Complejo Poro Nuclear/genética , Proteínas de Complejo Poro Nuclear/metabolismo , Subunidades de Proteína/metabolismo , ARN Interferente Pequeño/genética , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Ratas , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismoRESUMEN
Bronchopulmonary dysplasia (BPD), a multifactorial disease of preterm neonates of complex etiology, is a significant problem within very low birth weight infants. Nitric oxide (NO) has been implicated in both the pathogenesis and as a potential therapeutic of this disease. At this time, there is little direct evidence of the changes in NO production and metabolism that occur within BPD in humans. Animal models have implied that reduced nitric oxide synthase (NOS) expression and NO production in the early stages of the disease may be critical factors. However, inflammation and hence iNOS expression, is also thought to play a role. In the present study we have utilized pathological samples to determine changes in the expression of NOS and NO metabolites within late stage BPD. It is our contention that within these samples iNOS expression is increased and associated with increased NO metabolite production. Mild immunostaining of all three nitric oxide synthase (NOS) enzymes (neuronal, inducible and endothelial) is observed in control lung with tight localization to the endothelium and epithelial airway. This tight localization was lost in samples from subjects with BPD. There was also a marked increase in iNOS expression throughout the lung tissue with strong coexistence with an epithelial cell marker cytokeratin. NO reaction products are altered with BPD as evidenced by increased S-nitrosothiol (SNO) and strong nitrotyrosine (NO(2)Y) imunoreactivity. This study demonstrates a strong correlation between products of NO reactivity and NOS localization in BPD.
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Displasia Broncopulmonar/enzimología , Óxido Nítrico Sintasa/biosíntesis , Óxido Nítrico/metabolismo , Biomarcadores , Células Epiteliales/enzimología , Femenino , Expresión Génica , Edad Gestacional , Humanos , Recién Nacido , Recién Nacido de muy Bajo Peso , Queratinas , MasculinoRESUMEN
Accumulating evidence shows that S-nitrosothiols, formed by the addition of nitric oxide (NO) to a cysteine thiol, S-nitrosylation, are involved in basal cellular regulation. It has been proposed that SNO formation/removal may be disrupted in a variety of pathophysiological conditions. Two types of methodology are presently available to identify specific S-nitrosylated proteins: (1) derivatization and (2) post-purification chemical detection. Neither of these techniques allows for in situ visualization of SNOs. Recently, we demonstrated that an antibody generated to the SNO moiety could be used to detect SNO formation from each of three isoforms of NOS by immunohistochemistry. This chapter details the immunohistochemical methodology used to detect SNOs in situ, offering a potentially powerful alternative for detection of SNO within tissue sections.
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Anticuerpos Monoclonales/química , Óxido Nítrico/metabolismo , S-Nitrosotioles/metabolismo , Animales , Secciones por Congelación , Humanos , Inmunohistoquímica/métodos , Compuestos Nitrosos/metabolismo , Adhesión en Parafina , S-Nitrosotioles/análisisRESUMEN
Surfactant protein (SP)-D, a 43-kD multifunctional collagen-like lectin, is synthesized and secreted by the airway epithelium. SP-D knockout (SP-D [-/-]) mice exhibit an increase in the number and size of airway macrophages, peribronchiolar inflammation, increases in metalloproteinase activity, and development of emphysema. Nitric oxide (NO) is involved in a variety of signaling processes, and because altered NO metabolism has been observed in inflammation, we hypothesized that alterations in its metabolism would underlie the proinflammatory state observed in SP-D deficiency. Examination of the bronchial alveolar lavage (BAL) from SP-D (-/-) mice reveals a significant increase in protein and phospholipid content and total cell count. NO production and inducible NO synthase expression were increased in the BAL; however, there was a decline in S-nitrosothiol (SNO) content in the BAL and a loss of SNO immunoreactivity within the tissue. This decline in SNO was accompanied by an increase in nitrotyrosine staining. We conclude that inflammation that occurs in SP-D deficiency results in an increase in NO production and a shift in the chemistry and targets of NO. We speculate that the proinflammatory response due to SP-D deficiency results, in part, from a disruption of NO-mediated signaling within the innate immune system.