Patterns of Failure in Metastatic NSCLC Treated With First Line Pembrolizumab and Use of Local Therapy in Patients With Oligoprogression.

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.

Combined JAK inhibition and PD-1 immunotherapy for non-small cell lung cancer patients.

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.

Mitochondrial complex II prevents hypoxic but not calcium- and proapoptotic Bcl-2 protein-induced mitochondrial membrane potential loss.

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.

Outcomes in Patients With Non-small-cell Lung Cancer With Brain Metastases Treated With Pembrolizumab-based Therapy.

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.

Influence of TP53 Mutation on Survival in Patients With Advanced EGFR-Mutant Non-Small-Cell Lung Cancer.

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.

Immunohistochemical detection of S-nitrosylated proteins.

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.

Nitration of the mitochondrial complex I subunit NDUFB8 elicits RIP1- and RIP3-mediated necrosis.

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.

Expression of nitric oxide synthases and endogenous NO metabolism in bronchopulmonary dysplasia.

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.