SFTPB in serum extracellular vesicles as a biomarker of progressive pulmonary fibrosis.

Progressive pulmonary fibrosis (PPF), defined as the worsening of various interstitial lung diseases (ILDs), currently lacks useful biomarkers. To identify novel biomarkers for early detection of patients at risk of PPF, we performed a proteomic analysis of serum extracellular vesicles (EVs). Notably, the identified candidate biomarkers were enriched for lung-derived proteins participating in fibrosis-related pathways. Among them, pulmonary surfactant-associated protein B (SFTPB) in serum EVs could predict ILD progression better than the known biomarkers, serum KL-6 and SP-D, and it was identified as an independent prognostic factor from ILD-gender-age-physiology index. Subsequently, the utility of SFTPB for predicting ILD progression was evaluated further in 2 cohorts using serum EVs and serum, respectively, suggesting that SFTPB in serum EVs but not in serum was helpful. Among SFTPB forms, pro-SFTPB levels were increased in both serum EVs and lungs of patients with PPF compared with those of the control. Consistently, in a mouse model, the levels of pro-SFTPB, primarily originating from alveolar epithelial type 2 cells, were increased similarly in serum EVs and lungs, reflecting pro-fibrotic changes in the lungs, as supported by single-cell RNA sequencing. SFTPB, especially its pro-form, in serum EVs could serve as a biomarker for predicting ILD progression.

Sema6D forward signaling impairs T cell activation and proliferation in head and neck cancer.

Immune checkpoint inhibitors (ICIs) are indicated for a diverse range of cancer types, and characterizing the tumor immune microenvironment is critical for optimizing therapeutic strategies, including ICIs. T cell infiltration and activation status in the tumor microenvironment greatly affects the efficacy of ICIs. Here, we show that semaphorin 6D (Sema6D) forward signaling, which is reportedly involved in coordinating the orientation of cell development and migration as a guidance factor, impaired the infiltration and activation of tumor-specific CD8+ T cells in murine oral tumors. Sema6D expressed by nonhematopoietic cells was responsible for this phenotype. Plexin-A4, a receptor for Sema6D, inhibited T cell infiltration and partially suppressed CD8+ T cell activation and proliferation induced by Sema6D stimulation. Moreover, mouse oral tumors, which are resistant to PD-1-blocking treatment in wild-type mice, showed a response to the treatment in Sema6d-KO mice. Finally, analyses of public data sets of human head and neck squamous cell carcinoma, pan-cancer cohorts, and a retrospective cohort study showed that SEMA6D was mainly expressed by nonhematopoietic cells such as cancer cells, and SEMA6D expression was significantly negatively correlated with CD8A, PDCD1, IFNG, and GZMB expression. Thus, targeting Sema6D forward signaling is a promising option for increasing ICI efficacy.

Leucine-rich a-2 glycoprotein as a potential biomarker of idiopathic multicentric Castleman disease with pulmonary involvement: a single-center case-control study from Japan.

Background: There are no known biomarkers for monitoring disease activity in idiopathic multicentric Castleman disease (MCD) with pulmonary involvement. We investigated the utility of serum leucine-rich α2-glycoprotein levels, which reflects interleukin 6 independent inflammatory change, for monitoring disease activity in patients with idiopathic MCD with pulmonary involvement. Methods: We retrospectively examined cases of idiopathic MCD diagnosed at Osaka University Hospital. The serum levels of leucine-rich α2-glycoprotein were compared between patients with idiopathic MCD and healthy controls. The difference in leucine-rich α2-glycoprotein levels before and after treatment (∆leucine-rich α2-glycoprotein) was evaluated with respect to the relationship with pulmonary function. In addition, the relationship between cytokine and chemokine profiles and the leucine-rich α2-glycoprotein concentration was investigated. The results were analyzed using pathway analysis. Results: The leucine-rich α2-glycoprotein concentrations were significantly higher in treatment-naïve patients (n=5) than in healthy controls (n=3) (P=0.035). Further, the ∆leucine-rich α2-glycoprotein concentration was significantly correlated with ∆ percent diffusing capacity of the lung for carbon monoxide (r=-0.88, P=0.049) and tended to correlate with ∆ percent vital capacity (r=-0.68, P=0.21) although the difference was not significant for the latter association. The concentrations of chemokines and cytokines, such as CXCL9, CXCL11, CXCL1, and a proliferation-inducing ligand, were higher in the patient group than in the healthy control group. Enrichment analysis indicated that leucine-rich α2-glycoprotein could be elevated via the upregulation of chemokines in patients with idiopathic MCD using these parameters. Conclusions: Leucine-rich a2-glycoprotein may be useful for monitoring disease activity in patients with idiopathic MCD with pulmonary involvement.

Identification of CD14 and lipopolysaccharide-binding protein as novel biomarkers for sarcoidosis using proteomics of serum extracellular vesicles.

Sarcoidosis is a complex, polygenic, inflammatory granulomatous multi-organ disease of unknown cause. The granulomatous inflammation in sarcoidosis is driven by the interplay between T cells and macrophages. Extracellular vesicles (EVs) play important roles in intercellular communication. We subjected serum EVs, isolated by size exclusion chromatography, from seven patients with sarcoidosis and five control subjects to non-targeted proteomics analysis. Non-targeted, label-free proteomics analysis detected 2292 proteins in serum EVs; 42 proteins were up-regulated in patients with sarcoidosis relative to control subjects; and 324 proteins were down-regulated. The protein signature of EVs from patients with sarcoidosis reflected disease characteristics such as antigen presentation and immunological disease. Candidate biomarkers were further verified by targeted proteomics analysis (selected reaction monitoring) in 46 patients and 10 control subjects. Notably, CD14 and lipopolysaccharide-binding protein (LBP) were validated by targeted proteomics analysis. Up-regulation of these proteins was further confirmed by immunoblotting, and their expression was strongly increased in macrophages of lung granulomatous lesions. Consistent with these findings, CD14 levels were increased in lipopolysaccharide-stimulated macrophages during multinucleation, concomitant with increased levels of CD14 and LBP in EVs. The area under the curve values of CD14 and LBP were 0.81 and 0.84, respectively, and further increased to 0.98 in combination with angiotensin-converting enzyme and soluble interleukin-2 receptor. These findings suggest that CD14 and LBP in serum EVs, which are associated with granulomatous pathogenesis, can improve the diagnostic accuracy in patients with sarcoidosis.

IL-33 Induces Sema4A Expression in Dendritic Cells and Exerts Antitumor Immunity.

Cancer immunotherapy has shown great promise as a new standard therapeutic strategy against cancer. However, the response rate and survival benefit remain unsatisfactory because most current approaches, such as the use of immune checkpoint inhibitors, depend on spontaneous antitumor immune responses. One possibility for improving the efficacy of immunotherapy is to promote antitumor immunity using adjuvants or specific cytokines actively. IL-33 has been a candidate for such cytokine therapies, but it remains unclear how and in which situations IL-33 exerts antitumor immune effects. In this study, we demonstrate the potent antitumor effects of IL-33 using syngeneic mouse models, which included marked inhibition of tumor growth and upregulation of IFN-γ production by tumor-infiltrating CD8+ T cells. Of note, IL-33 induced dendritic cells to express semaphorin 4A (Sema4A), and the absence of Sema4A abolished the antitumor activity of IL-33, indicating that Sema4A is intrinsically required for the antitumor effects of IL-33 in mice. Collectively, these results not only present IL-33 and Sema4A as potential therapeutic targets but also shed light on the potential use of Sema4A as a biomarker for dendritic cell activation status, which has great value in various fields of cancer research, including vaccine development.

Proteomics of serum extracellular vesicles identifies a novel COPD biomarker, fibulin-3 from elastic fibres.

There is an unmet need for novel biomarkers in the diagnosis of multifactorial COPD. We applied next-generation proteomics to serum extracellular vesicles (EVs) to discover novel COPD biomarkers. EVs from 10 patients with COPD and six healthy controls were analysed by tandem mass tag-based non-targeted proteomics, and those from elastase-treated mouse models of emphysema were also analysed by non-targeted proteomics. For validation, EVs from 23 patients with COPD and 20 healthy controls were validated by targeted proteomics. Using non-targeted proteomics, we identified 406 proteins, 34 of which were significantly upregulated in patients with COPD. Of note, the EV protein signature from patients with COPD reflected inflammation and remodelling. We also identified 63 upregulated candidates from 1956 proteins by analysing EVs isolated from mouse models. Combining human and mouse biomarker candidates, we validated 45 proteins by targeted proteomics, selected reaction monitoring. Notably, levels of fibulin-3, tripeptidyl-peptidase 2, fibulin-1, and soluble scavenger receptor cysteine-rich domain-containing protein were significantly higher in patients with COPD. Moreover, six proteins; fibulin-3, tripeptidyl-peptidase 2, UTP-glucose-1-phosphate uridylyl transferase, CD81, CD177, and oncoprotein-induced transcript 3, were correlated with emphysema. Upregulation of fibulin-3 was confirmed by immunoblotting of EVs and immunohistochemistry in lungs. Strikingly, fibulin-3 knockout mice spontaneously developed emphysema with age, as evidenced by alveolar enlargement and elastin destruction. We discovered potential pathogenic biomarkers for COPD using next-generation proteomics of EVs. This is a novel strategy for biomarker discovery and precision medicine.

Pathological and therapeutic implications of eosinophil-derived semaphorin 4D in eosinophilic chronic rhinosinusitis.

BACKGROUND: Eosinophilic chronic rhinosinusitis (ECRS) is a subtype of chronic rhinosinusitis. Clinical markers for ECRS disease activity and treatment strategies have not been sufficiently established. Although semaphorins are originally identified as neuronal guidance factors, it is becoming clear that they play key roles in immune regulation and inflammatory diseases. OBJECTIVE: We sought to investigate the pathological functions and therapeutic potential of semaphorin 4D (SEMA4D) in ECRS. METHODS: Serum soluble SEMA4D levels in patients with paranasal sinus diseases were measured by ELISA. The expression of SEMA4D in blood cells and nasal polyp tissues was assessed by flow cytometry and immunohistochemistry, respectively. Generation of soluble SEMA4D was evaluated in matrix metalloproteinase-treated eosinophils. Endothelial cells were stimulated with recombinant SEMA4D, followed by eosinophil transendothelial migration assays. Allergic chronic rhinosinusitis was induced in mice using Aspergillus protease with ovalbumin. The efficacy of treatment with anti-SEMA4D antibody was evaluated histologically and by nasal lavage fluid analysis. RESULTS: Serum soluble SEMA4D levels were elevated in patients with ECRS and positively correlated with disease severity. Tissue-infiltrated eosinophils in nasal polyps from patients with ECRS stained strongly with anti-SEMA4D antibody. Cell surface expression of SEMA4D on eosinophils from patients with ECRS was reduced, which was due to matrix metalloproteinase-9-mediated cleavage of membrane SEMA4D. Soluble SEMA4D induced eosinophil transendothelial migration. Treatment with anti-SEMA4D antibody ameliorated eosinophilic infiltration in sinus tissues and nasal lavage fluid in the ECRS animal model. CONCLUSIONS: Eosinophil-derived SEMA4D aggravates ECRS. Levels of serum SEMA4D reflect disease severity, and anti-SEMA4D antibody has therapeutic potential as a treatment for ECRS.

Semaphorin 7A promotes EGFR-TKI resistance in EGFR mutant lung adenocarcinoma cells.

Although responses to EGFR tyrosine kinase inhibitors (EGFR-TKIs) are initially positive, 30%-40% of patients with EGFR-mutant tumors do not respond well to EGFR-TKIs, and most lung cancer patients harboring EGFR mutations experience relapse with resistance. Therefore, it is necessary to identify not only the mechanisms underlying EGFR-TKI resistance, but also potentially novel therapeutic targets and/or predictive biomarkers for EGFR-mutant lung adenocarcinoma. We found that the GPI-anchored protein semaphorin 7A (SEMA7A) is highly induced by the EGFR pathway, via mTOR signaling, and that expression levels of SEMA7A in human lung adenocarcinoma specimens were correlated with mTOR activation. Investigations using cell culture and animal models demonstrated that loss or overexpression of SEMA7A made cells less or more resistant to EGFR-TKIs, respectively. The resistance was due to the inhibition of apoptosis by aberrant activation of ERK. The ERK signal was suppressed by knockdown of integrin ß1 (ITGB1). Furthermore, in patients with EGFR mutant tumors, higher SEMA7A expression in clinical samples predicted poorer response to EGFR-TKI treatment. Collectively, these data show that the SEMA7A-ITGB1 axis plays pivotal roles in EGFR-TKI resistance mediated by ERK activation and apoptosis inhibition. Moreover, our results reveal the potential utility of SEMA7A not only as a predictive biomarker, but also as a potentially novel therapeutic target in EGFR-mutant lung adenocarcinoma.

Clinical implications of monitoring nivolumab immunokinetics in non-small cell lung cancer patients.

BACKGROUND: The PD-1-blocking antibody nivolumab persists in patients several weeks after the last infusion. However, no study has systematically evaluated the maximum duration that the antibody persists on T cells or the association between this duration and residual therapeutic efficacy or potential adverse events. METHODS: To define the duration of binding and residual efficacy of nivolumab after discontinuation, we developed a simplified strategy for T cell monitoring and used it to analyze T cells from peripheral blood from 11 non-small cell lung cancer patients previously treated with nivolumab. To determine the suitability of our method for other applications, we compared transcriptome profiles between nivolumab-bound and nivolumab-unbound CD8 T cells. We also applied T cell monitoring in 2 nivolumab-treated patients who developed progressive lung tumors during long-term follow-up. RESULTS: Prolonged nivolumab binding was detected more than 20 weeks after the last infusion, regardless of the total number of nivolumab infusions (2-15 doses) or type of subsequent treatment, in 9 of the 11 cases in which long-term monitoring was possible. Ki-67 positivity, a proliferation marker, in T cells decreased in patients with progressive disease. Transcriptome profiling identified the signals regulating activation of nivolumab-bound T cells, which may contribute to nivolumab resistance. In 2 patients who restarted nivolumab, T cell proliferation markers exhibited the opposite trend and correlated with clinical response. CONCLUSIONS: Although only a few samples were analyzed, our strategy of monitoring both nivolumab binding and Ki-67 in T cells might help determine residual efficacy under various types of concurrent or subsequent treatment. TRIAL REGISTRATION: University Hospital Medical Information Network Clinical Trials Registry, UMIN000024623. FUNDING: This work was supported by Japan Society for the Promotion of Science KAKENHI (JP17K16045, JP18H05282, and JP15K09220), Japan Agency for Medical Research and Development (JP17cm0106310, JP18cm0106335 and JP18cm059042), and Core Research for Evolutional Science and Technology (JPMJCR16G2).

Phase II trial of induction chemotherapy of pemetrexed plus split-dose cisplatin followed by pemetrexed maintenance for untreated non-squamous non-small-cell lung cancer.

PURPOSE: We conducted a phase II trial to evaluate the efficacy and safety of induction chemotherapy of pemetrexed plus split-dose cisplatin followed by pemetrexed maintenance for advanced non-squamous non-small-cell lung cancer (NSCLC). METHODS: Patients with advanced or recurrent untreated non-squamous NSCLC received split-dose cisplatin (40 mg/m2, days 1 and 8) plus pemetrexed (500 mg/m2, day 1) tri-weekly. After four cycles of induction, patients without disease progression received pemetrexed maintenance until disease progression or unacceptable toxicity. The primary endpoint was the 1-year survival rate. The secondary endpoints were progression-free survival (PFS), overall survival (OS), response in induction phase, and safety. RESULTS: From February 2012 to September 2014, 53 assessable patients were enrolled in this study. Thirty-eight (71.7%) patients completed induction therapy, while 35 (66.0%) received maintenance therapy. The 1-year survival rate was 67.7%. The median PFS and OS were 5.3 and 18.6 months, respectively. The response rate and disease control rate (DCR) during the induction phase were 37.7 and 86.8%, respectively. Eight patients (15.1%) discontinued the therapy due to adverse events (AEs) during the induction phase, but both hematological and non-hematological AEs were infrequent. CONCLUSIONS: Treatment with induction chemotherapy of pemetrexed plus split-dose cisplatin showed a promising 1-year survival rate, DCR, and transition rate into maintenance phase. This regimen is feasible and well-tolerated. A phase III study comparing this regimen with conventional tri-weekly regimen is warranted.

Phase II study of S-1 plus bevacizumab combination therapy for patients previously treated for non-squamous non-small cell lung cancer.

PURPOSE: To assess the efficacy and toxicity of S-1 and bevacizumab combination therapy for patients previously treated for advanced non-squamous non-small cell lung cancer (NSCLC). METHODS: This was a prospective, multi-center, single-arm phase II study. Patients with non-squamous NSCLC who had experienced progression after cytotoxic chemotherapy were enrolled. Oral S-1 was administered on days 1-14 of a 21-day cycle, and bevacizumab (15 mg/kg) was given intravenously on day 1. Patients received S-1 adjusted on the basis of their creatinine clearance and body surface area. The primary endpoint was response rate (RR); secondary endpoints were progression-free survival (PFS), overall survival (OS), and safety. RESULTS: We enrolled 30 patients. One patient had never received platinum-based therapy. Five patients had activating mutations of the epidermal growth factor receptor gene, of whom four had received tyrosine kinase inhibitors before this study. The RR was 6.7% [95% confidence interval (CI) 1.8-21.3%], and the disease control rate (DCR) was 80% (95% CI 62.7-90.5%). Median PFS was 4.8 months (95% CI 2.7-6.4 months], and median OS was 13.8 months (95% CI 8.4 months-not applicable). Patients did not experience any Grade 4 toxicity or treatment-related death. Grade 3 hematologic toxicity (anemia) occurred in one patient (3.3%). The main Grade 3 non-hematologic toxicities were anorexia (10%), infection (10%), and diarrhea (6.7%). CONCLUSION: The addition of bevacizumab to S-1 was tolerable, but not beneficial for patients with previously treated non-squamous NSCLC. We do not recommend further study of this regimen.