A Phase II Study of High-Flow Nasal Cannula for Relieving Dyspnea in Advanced Cancer Patients

CONTEXT

The efficacy and tolerability of high-flow nasal cannula (HFNC) for relieving dyspnea in advanced cancer patients with limited prognosis requires elucidation.

OBJECTIVES

The primary aim of this trial was to assess the efficacy and tolerability of HFNC regarding dyspnea including severe as well as moderate for longer durations in patients under palliative care.

METHODS

In this prospective study, hospitalized patients with advanced cancer who had dyspnea at rest (numeric rating scale, NRS≥3) and hypoxemia were enrolled. They were treated with HFNC for five days in the respiratory unit. Primary endpoint was mean change of modified Borg scale at 24 hours. Key secondary endpoints consisted of mean changes in modified Borg scale during the study period and feasibility (Trial Identifier, UMIN000035738).

RESULTS

Between February 2019 and February 2022, 25 patients were enrolled and 21 were analyzed. Twenty patients used inspired oxygen and the mean fraction of inspired oxygen (FiO2) was 0.34 (range, 0.21-1.0). At baseline, mean NRS (dyspnea) was 5.9 (range, 3-10). Median survival time was 19 days (range, 3-657). The mean change of modified Borg scale was 1.4 (80% confidence interval [CI]: 0.8-1.9) at 24 hours, 12 patients (57%) showed 1.0 points improvement of modified Borg scale. Within two hours, 15 patients showed 1.0 points improvement of modified Borg scale and such early responders were likely to maintain dyspnea improvement for 24 hours. Nineteen patients could continue HFNC for 24 hours and 11 patients completed five days of HFNC.

CONCLUSION

To our knowledge, this trial is the first prospective study to assess the five-day efficacy and tolerability of HFNC for dyspnea in patients under palliative care. Although this did not reach the prespecified endpoint, about half of the patients showed 1.0 point improvement, a minimally clinically important difference (MCID) in the chronic lung disease. HFNC can be a palliative treatment option in advanced cancer patients with dyspnea.

Treatment of refractory localized pulmonary nocardiosis caused by Nocardia mexicana with a combination of medication and surgery

Pulmonary nocardiosis is a rare disease that is often difficult to cure because of its tendency to recur. Here, we report a case of refractory localized pulmonary nocardiosis caused by Nocardia mexicana. A 60-year-old Japanese woman had recurring pulmonary nocardiosis four times previously and each time she was treated with antibiotics for a sufficient duration; nevertheless, the disease continued to recur, probably because of resistance to antibiotics. As a fifth treatment, we performed middle lobe resection and pre- and post-operative antimicrobial therapy for 6 months. The combination of medication and surgery was useful for treating refractory localized pulmonary nocardiosis.

Clinical Efficacy and Safety of Nivolumab in Japanese Patients With Malignant Pleural Mesothelioma: 3-Year Results of the MERIT Study

Introduction

We examined the long-term efficacy and safety of nivolumab, a human monoclonal antibody that inhibits interactions between the programmed cell death protein-1 receptor and its ligands (programmed death-ligand 1 and programmed death-ligand 2), in Japanese patients with malignant pleural mesothelioma (MPM).

Methods

Japanese patients with previously treated MPM (one or two regimens) were enrolled in a single-arm, phase 2 study and received nivolumab intravenously 240 mg every 2 weeks until progressive disease or unacceptable toxicity. The primary end point was the centrally assessed objective response rate. Other end points included overall survival (OS), progression-free survival (PFS), treatment-related adverse events, and patient-reported outcomes (Lung Cancer Symptom Scale for mesothelioma and EuroQOL visual analog scale). Patient enrollment started on June 16, 2016. Here, we report 3-year follow-up data (cutoff date: November 12, 2019).

Results

Thirty-four patients were enrolled. The centrally assessed objective response rate was previously reported (29.4%). The 2- and 3-year OS rates were 35.3% and 23.5%, respectively, and the corresponding PFS rates were 17.0% and 12.7%. Median OS and PFS were 17.3 and 5.9 months, respectively. Eight patients were alive at 3 years of follow-up. Nivolumab was well tolerated and no new safety signals were found. The patient-reported outcomes were maintained without marked deteriorations during the study.

Conclusions

Our results reveal clinically relevant long-term efficacy and safety of nivolumab for the treatment of MPM.

A pilot study investigating the effect of pimobendan on the cardiac rhythm and selected echocardiographic parameters of healthy cats

INTRODUCTION

The effects of pimobendan on the heart rhythm in cats are unknown. The purpose of this pilot study was to evaluate the effect of pimobendan on the cardiac rhythm and selected echocardiographic parameters of cats.

ANIMALS, MATERIALS, AND METHODS

Six clinically healthy cats received each of four medication protocols for 15 days, with a washout period of at least one month between each protocol. The protocols were, pimobendan 0.5 mg/kg twice daily (high dosage group), pimobendan 0.25 mg/kg twice daily (standard dosage group), pimobendan 0.125 mg/kg twice daily (low dosage group), and Biofermin R, one tablet twice daily (placebo group). Twenty-four-hour ambulatory electrocardiogram recordings, blood pressure measurements, and echocardiographic examinations were performed after two weeks of each medication protocol. Electrocardiographic, echocardiographic, and blood pressure parameters were compared between the four groups.

RESULTS

The total number of escape/idioventricular/idiojunctional complexes in the high dosage group was significantly higher compared with the placebo, low dosage, and standard dosage groups (p < 0.001). The blood pressure; total number of heart beats per day; and mean, minimum, and maximum heart rates were not significantly different between the groups. The longitudinal strain rate and calculated cardiac output were significantly increased in the high and standard dosage groups.

CONCLUSIONS

The administration of pimobendan, especially at high doses, was associated with increased numbers of escape/idioventricular/idiojunctional complexes in some cats and echocardiographic parameters. Further studies are warranted to investigate both the mechanism underlying the observed changes and what, if any, clinical implications these changes might have in cats with heart disease.

Prospective, multicentre, single-arm phase II trial of pembrolizumab combined with carboplatin and pemetrexed in elderly patients with advanced, non-squamous non-small cell lung cancer

INTRODUCTION

Triplet regimen of carboplatin or cisplatin with pemetrexed and pembrolizumab is a standard treatment for patients with advanced, chemo-naïve, non-squamous non-small cell lung cancer. However, subgroup analysis for patients aged ≥75 years indicated that elderly patients who received the triplet regimen may have had shorter survival times than if they had chemotherapy alone (HR of 2.09). Treatments in the elderly are not always as effective or safe as for non-elderly patients, so there remains concern over whether the triplet regimen can be widely used in the elderly.

METHODS AND ANALYSIS

This is a single-arm, prospective, multicentre phase II study. The primary endpoint is set as the overall response rate according to Response Evaluation Criteria in Solid Tumors V.1.1. Secondary endpoints are progression-free survival, disease control rate and safety. This trial will enrol 22 patients.

ETHICS AND DISSEMINATION

This study was approved by the Wakayama Medical University Central Review Board on 2 December 2019 (approval number: W-32). Patients have been enrolled since February 2020. As the study will complete accrual in January 2022, results will be submitted for publication in peer-reviewed medical journals within 2023 and international scientific meetings. This study will provide significant information on whether the triplet regimens are clinically beneficial to elderly patients.

TRIAL REGISTRATION NUMBER

Japan Registry of Clinical Trials (jRCTs051190095).

Detection of AXL expression in circulating tumor cells of lung cancer patients using an automated microcavity array system

Noninvasive diagnostics using circulating tumor cells (CTCs) are expected to be useful for decision making in precision cancer therapy. AXL, a receptor tyrosine kinase is associated with tumor progression, epithelial‐to‐mesenchymal transition (EMT), and drug resistance, and is a potential therapeutic target. However, the epithelial markers generally used for CTC detection may be not enough to detect AXL‐expressing CTCs due to EMT. Here, we evaluated the detection of AXL‐expressing CTCs using the mesenchymal marker vimentin with a microcavity array system. To evaluate the recovery of cancer cells, spike‐in experiments were performed using cell lines with varying cytokeratin (CK) or vimentin (VM) expression levels. With high CK and low VM‐expressing cell lines, PC‐9 and HCC827, the recovery rate of AXL‐expressing cancer cells was 1%‐17% using either CK or VM as markers. Whereas, with low CK and high VM‐expressing cell lines, MDA‐MB231 and H1299, it was 52%‐75% using CK and 72%‐88% using VM as a marker. For clinical evaluation, peripheral blood was collected from 20 non–small cell lung cancer patients and CTCs were detected using CK or VM as markers in parallel. Significantly more AXL‐expressing single CTCs were detected in VM‐positive than CK‐positive CTCs (P < .001). Furthermore, CTC clusters were identified only among VM‐positive CTCs in 20% of patients. Patients with one or more prior treatments harbored significantly more VM‐positive AXL‐expressing CTCs, suggesting the involvement of these CTCs in drug resistance. These results indicate the necessity of integrating mesenchymal markers with CTC detection and this should be further evaluated clinically.

Abstract 414: Detection of AXL-expressing circulating tumor cells (CTCs) in non-small-cell lung cancer (NSCLC) patients using an automated microcavity array (MCA) system

Purpose: Noninvasive diagnostics has been developed over the last decade and we have previously reported that CTCs can be utilized for evaluating molecular features of NSCLC. AXL, a receptor tyrosine kinase is linked to epithelial-to-mesenchymal transition (EMT) leading to cancer progression and regarded as a potential therapeutic target. However, many of current technologies rely on epithelial markers to detect CTCs and that makes it difficult to detect AXL-expressing CTCs. Here, we established the detection of AXL expression on CTCs using MCA system.

Methods: Preclinical experiments were performed using NSCLC cell lines H1299, PC9, and HCC827 and a breast cancer cell line MDA-MB231 with varying cytokeratin (CK) and AXL expression levels. The cells were spiked into 3 ml of peripheral blood from healthy donors, then enriched using MCA system, and detected by staining for CD45, DAPI, CK or vimentin (VM) with the addition staining for AXL. For clinical evaluation, 3ml of peripheral blood was collected from advanced NSCLC patients.

Results: DAPI-positive, CK or VM-positive, and CD45-negative cells were defined as CTCs. In spike-in experiments, when CK was used as a marker, AXL expression was detected in 5 and 17% of high CK-expressing HCC827 and PC9 cells, respectively and detected in 52 and 75% of low CK-expressing H1299 and MDA-MB231 cells, respectively. On the other hand, when VM was used as a marker, AXL expression was detected in 72 and 88% of high VM-expressing MDA-MB231 and H1299 cells, respectively whereas detected in 1 and 7% of PC9 and HCC827 cells with low VM expression, respectively. Twenty-four patients were enrolled in the clinical study. The patient characteristics were as follows: median age 69.5 years (range, 49-84); male 88%; stage III/IV, 25/75%; adenocarcinoma/ squamous cell carcinoma/ other, 63/33/4%. Both CK and VM staining in 17 patients, only CK in 6 patients, and only VM in 1 patient were performed. CK-positive single CTCs were detected in all patients (median, 4; range, 1-50) and AXL-expressing CK-positive single CTCs were detected in 26% of patients (median, 0; range, 0-1). On the other hand, VM-positive single CTCs were detected in 94% of patients (median, 6.5; range, 0-128) and AXL-expressing VM-positive single CTCs were detected in 89% of patients (median, 1; range, 0-106). Significantly more AXL-expressing single CTCs were detected in VM-positive than CK-positive (p &lt; 0.001). Notably, all of identified CTC clusters were positive for only VM, not CK and AXL-expressing CTC clusters were detected in 33% of patients (median, 0; range, 0-22).

Conclusion: Our data indicate that incorporating VM staining is necessary to detect AXL-positive CTCs due to EMT. Further clinical evaluation is warranted for validating the method and the clinical significance of AXL-positive CTCs.

Citation Format: Mio Ikeda, Yasuhiro Koh, Shunsuke Teraoka, Jun Oyanagi, Kuninobu Kanai, Atsushi Hayata, Nahomi Tokudome, Hiroaki Akamatsu, Yuichi Ozawa, Keiichiro Akamatsu, Masayuki Higuchi, Masanori Nakanishi, Hiroki Ueda, Nobuyuki Yamamoto. Detection of AXL-expressing circulating tumor cells (CTCs) in non-small-cell lung cancer (NSCLC) patients using an automated microcavity array (MCA) system [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 414.

Abstract 416: Predictive significance of serum protein levels in advanced non-small-cell lung cancer patients treated with pembrolizumab

Background: We have previously reported that serum IL-8 and G-CSF were correlated with clinical benefit and immune-related adverse events (irAE), respectively in non-small-cell lung cancer (NSCLC) patients treated with nivolumab. Here, we measured multiple serum proteins serially in NSCLC patients treated with pembrolizumab and explored the potential of predicting clinical response or irAE onset. This study was registered at UMIN (ID: 000024414).

Patients and Methods: Advanced NSCLC patients received pembrolizumab monotherapy (200 mg/body, q3W) until progressive disease (PD) or unacceptable toxicity. Serum samples were collected at baseline and at week 6. Best response was classified into partial response (PR), stable disease (SD), or progressive disease (PD) according to RECIST v1.1. Using LuminexTM xMapTM technology, serum levels of 41 proteins consisting of cytokines, chemokines, growth factors, and angiogenesis factors were measured. All statistical analyses were carried out using JMP Pro software (ver. 13.0) and Mann-Whitney U test were performed accordingly. A p value &lt;0.05 was considered as significant.

Results: Thirty-seven patients were registered in the study between March 2017 and October 2018 at Wakayama Medical University Hospital and 32 were included in the final analysis. Demographics of the patients were as follows: median age 70 (range, 50 to 91); male 75%; smoker 88%; stage III/IV, 22/78%; squamous/non-squamous, 31/69%, previous treatment; 0/1≤, 47/53%. Objective response rate was 28% and disease control rate was 56% in the entire cohort and 40% and 67%, respectively in the first-line subset. Among 41 serum proteins measured, no serum protein at baseline was associated with efficacy or irAE onset in the entire cohort. Levels of serum VEGF-C and sCD40L at baseline, however, in the first-line subset were found significantly lower in the patient who had PR and SD than those who did not. RANTES was also found significantly lower in patients who had PR in the 2nd or later line subset. With regard to irAE prediction, changes of HB-EGF levels between baseline and week 6 were significantly smaller in irAE patients in the entire cohort and changes of MCP-1 levels were significantly smaller in irAE patients in second or later line subset. The serum proteins identified in the current study were not overlapped with those identified in advanced NSCLC patients treated with nivolumab in the previous study.

Conclusions: We identified potential serum protein markers associated with clinical benefit and irAE from pembrolizumab treatment in advanced NSCLC by multi-analyte protein-based assay. Our results suggest that serum proteins associated with efficacy and irAE may vary among different anti-PD-1 antibodies and also between in the first-line setting and later one.

Citation Format: Jun Oyanagi, Yasuhiro Koh, Shunsuke Teraoka, Kuninobu Kanai, Atsuhsi Hayata, Nahomi Tokudome, Hiroaki Akamatsu, Yuichi Ozawa, Keiichiro Akamatsu, Masanori Nakanishi, Hiroki Ueda, Nobuyuki Yamamoto. Predictive significance of serum protein levels in advanced non-small-cell lung cancer patients treated with pembrolizumab [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 416.

Clinical Efficacy and Safety of Nivolumab: Results of a Multicenter, Open-label, Single-arm, Japanese Phase II study in Malignant Pleural Mesothelioma (MERIT)

PURPOSE

Malignant pleural mesothelioma (MPM) is a rare and aggressive malignancy with poor prognosis. Patients with MPM who do not respond to standard first-line chemotherapy have limited treatment options. We evaluated the efficacy and safety of nivolumab, an immune checkpoint inhibitor, for the treatment of advanced or metastatic MPM.

PATIENTS AND METHODS

Japanese patients with unresectable, advanced, or metastatic MPM resistant or intolerant to ≤2 regimens of chemotherapy and ≥1 measurable lesion(s) were enrolled. Patients received nivolumab 240 mg intravenously every 2 weeks until progressive disease or unacceptable toxicity. The primary endpoint was objective response rate by central assessment according to the Modified Response Evaluation Criteria in Solid Tumors. Adverse events (AEs) and treatment-related AEs (TRAEs) were evaluated.

RESULTS

Thirty-four patients were enrolled between July 2016 and October 2016. Median follow-up was 16.8 (range: 1.8-20.2) months. Ten (29%, 95% confidence interval, 16.8-46.2) patients showed a centrally assessed objective response. The objective response rates were 26% (7/27), 67% (2/3), and 25% (1/4) patients for epithelioid, sarcomatoid, and biphasic histologic subtypes, respectively. Median duration of response was 11.1 months with a 68% disease control rate. Median overall survival and progression-free survival were 17.3 and 6.1 months, respectively. The objective response rate was 40% with programmed death-ligand 1 expression ≥1% and 8% with <1%. Thirty-two patients (94%) experienced AEs and 26 (76%) experienced TRAEs.

CONCLUSIONS

Nivolumab met the primary endpoint as second- or third-line treatment for patients with MPM and showed promising efficacy with manageable toxicity.See related commentary by Mansfield and Zauderer, p. 5438.

Heterogeneous Expression of Programmed Death Receptor-ligand 1 on Circulating Tumor Cells in Patients With Lung Cancer

BACKGROUND

Blockade of the programmed death receptor-1 (PD-1) pathway is effective against solid tumors including lung cancer. PD-ligand 1 (PD-L1) expression on tumor tissue serves as a predictive biomarker for the efficacy of PD-1 pathway blockade. Here, we evaluated the expression of PD-L1 on circulating tumor cells (CTCs) in patients with lung cancer.

MATERIALS AND METHODS

Peripheral whole blood (3 mL) was collected from patients, and CTCs and PD-L1 expression were detected using a microcavity array (MCA) system. Immunohistochemistry for PD-L1 detection was also performed using matched tumor tissues.

RESULTS

Sixty-seven patients with lung cancer were enrolled in the study between July 2015 and April 2016 at Wakayama Medical University Hospital. The characteristics of the patients were as follows: median age, 71 years (range, 39-86 years); male, 72%; stage II to III/IV, 14%/85%; non-small-cell lung cancer/small-cell lung cancer/other, 73%/21%/6%. CTCs were detected in 66 of 67 patients (median, 19; range, 0-115), and more than 5 CTCs were detected in 78% of patients. PD-L1-expressing CTCs were detected in 73% of patients, and the proportion score of PD-L1-expressing CTCs ranged from 3% to 100%, suggesting intra-patient heterogeneity of PD-L1 expression on CTCs. Tumor tissues were available from 27 patients and were immunostained for PD-L1, and no correlation was observed between tumor tissues and CTCs based on the proportion score (R² = 0.0103).

CONCLUSION

PD-L1 expression was detectable on CTCs in patients with lung cancer, and intra-patient heterogeneity was observed. No correlation was observed between PD-L1 expression in tumor tissues and CTCs.

Predictive value of serum protein levels in patients with advanced non-small cell lung cancer treated with nivolumab

BACKGROUND

Although programmed cell death-ligand-1 (PD-L1) expression in tumor tissue has been established as predictive biomarker for the anti-programmed cell death-1 (PD-1) antibody treatment of non-small-cell lung cancer (NSCLC), additional biomarkers are critically needed. We evaluated serum proteins relevant to immune checkpoint blockade in patients with NSCLC treated with nivolumab to identify novel non-invasive predictive biomarkers.

PATIENTS AND METHODS

Patients with advanced NSCLC, who had failed at least one prior chemotherapy regimen, received nivolumab monotherapy (3 mg/kg, Q2W) until progressive disease (PD) or unacceptable toxicity was observed. Blood samples were collected at baseline and week 4. Fifty-seven serum protein levels were quantified with a Milliplex MAP assay. The associations of both clinical benefit (CB) and the onset of immune related adverse events (irAEs) with serum proteins levels were evaluated.

RESULTS

Thirty-eight patients with advanced NSCLC were enrolled in the study, with 38 and 32 paired serum samples at baseline and week 4 being available for efficacy analysis and irAE analysis, respectively. In durable CB (DCB) patients compared with non-DCB patients, the baseline serum levels of BMP-9 were significantly higher, whereas the follistatin, IL-8, IP-10, and TNF-α levels were significantly lower. In irAE patients compared with non-irAE patients the serum levels of G-CSF and RANTES at week 4 were significantly higher, whereas the levels of leptin were significantly lower. A multivariate analysis revealed that follistatin and IP-10 were statistically associated with DCB (p < 0.05) and RANTES was associated with irAE onset (p < 0.05). In a subset of irAE-developed patients, RANTES levels decreased after steroid administration, supporting its involvement in irAE.

CONCLUSION

Serum proteins have the potential to be predictive markers for DCB and irAEs onset in patients with NSCLC treated with nivolumab. In addition, antitumor activity and irAEs may not be regulated by the same mechanisms.

Abstract 2608: Predictive values of serum protein levels in advanced non-small cell lung cancer patients treated with nivolumab

Background: Though PD-ligand 1 (PD-L1) expression on tumor tissue has been established as companion diagnostics in non-small-cell lung cancer (NSCLC) for anti-PD-L1 treatment, additional biomarkers to enrich the patients likely to benefit from the therapy are critically needed. Here, we conducted a serial evaluation of multiple serum proteins relevant to the modulation of immune system in NSCLC patients treated with nivolumab.

Patients and Methods: Advanced NSCLC patients after failure of at least one prior chemotherapy regimen received nivolumab monotherapy (3mg/kg, q2W) until progressive disease (PD) or unacceptable toxicity. Serum samples were collected at baseline and at week 4. Best response was classified into partial response (PR), stable disease (SD), or progressive disease (PD) according to RECIST v1.1. Using LuminexTM xMapTM technology, serum levels of 54 proteins consisting of cytokines, chemokines, growth factors, and angiogenesis factors were measured. All statistical analyses were carried out using JMP Pro software (ver. 13.0) and Mann-Whitney U test and Spearman's test were performed accordingly. A p value &lt;0.05 was considered as significant.

Results: Thirty-eight patients were registered in the study between January 2016 and March 2017 at Wakayama Medical University Hospital and 34 were included in the final analysis. Demographics of the patients were as follows: median age 68 (range, 49 to 86); male 73 %; stage IV, 100 %; squamous/non-squamous, 30/70 %. Overall response rate was 22% (7/34), and disease control rate was 53% (18/34). Among 54 serum proteins measured serially, the level of serum TNF-α was significantly lower at baseline in non-PD patients than PD patients (p &lt; 0.05). The level of TNF-α was also correlated with longer progression free survival (PFS) (r= -0.5693). Serum IL-8 level at week 4 in PR patients were significantly lower than those in non-PR patients (p &lt;0.01) though no difference was observed at baseline between the two, supporting the relevance of serum IL-8 level to the efficacy of nivolumab. Correlation between IL-8 levels at week 4 and longer PFS turned out to be more significant (r=-0.6864). In addition, serum levels of VEGF-A, TGF-β1 and PDGF-AB/BB were significantly lower in PR patients than those in non-PR patients at week 4 (p &lt;0.05). However, these protein levels were not correlated with PFS.

Conclusions: We identified that the serum levels of IL-8, TNF-α, VEGF-A, TGF-β1 and PDGF-AB/BB as potential biomarkers to predict clinical benefit from nivolumab treatment in advanced NSCLC by multi-analyte protein-based assay. Incorporating additional serum protein levels may have potential to improve the patient enrichment besides previously reported potential biomarkers such as IL-8 and VEGF levels. Further evaluation is warranted in a larger cohort to validate the findings.

Citation Format: Jun Oyanagi, Yasuhiro Koh, Hiroaki Akamatsu, Kuninobu Kanai, Atsushi Hayata, Nahomi Tokudome, Keiichiro Akamatsu, Keiichiro Akamatsu, Masanori Nakanishi, Hiroki Ueda, Nobuyuki Yamamoto. Predictive values of serum protein levels in advanced non-small cell lung cancer patients treated with nivolumab [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2608.

Abstract 5595: Predictive impact of sequential evaluation of PD-L1-expressing circulating tumor cells in NSCLC patients treated with nivolumab

Background: Anti-PD-1 antibody nivolumab has become a new standard treatment for pretreated, advanced non-small cell lung cancer (NSCLC). Although PD-L1 expression on tumor tissue has a predictive value, significance of its expression on circulating tumor cells (CTCs) is unknown. Here, we conducted a sequential evaluation of PD-1-expressing CTCs in NSCLC patients treated with nivolumab.

Methods: Advanced NSCLC patients who received nivolumab at Wakayama Medical University Hospital were enrolled in the study (UMIN000024414). Nivolumab was administered 3 mg/kg bi-weekly until progressive disease (PD) or unacceptable toxicity. Peripheral whole blood (3 mL) was collected in an EDTA collection tube (BD vacutainer) and processed within 3 hours for CTC evaluation at baseline, week 4 and week 8. CTCs were detected using automated microcavity array system (Hitachi Chemical Co.). PD-L1 expression was immunohistochemically examined on both tumor tissues and CTCs using anti-PD-L1 antibody, clone 28-8 (Abcam).

Results: Thirty-eight patients were registered in the study between January 2016 and September 2016. Clinical characteristics of the patients were as follows: median age 68 (range, 49 to 86); male 73 %; stage IV 100 %; squamous/non-squamous, 30/65 %. Regarding nivolumab treatment, overall response rate (ORR) was 22% (95% confidence interval [CI]: 10-38%), and median progression-free survival (PFS) was 62 days (95%CI: 40-235 days). At baseline, CTCs were detected in all patients (median, 15; range, 1-90) and PD-L1-expressing CTCs were detected in 87% of patients. Tumor proportion score (TPS) of PD-L1 expression on CTCs varied from 6% to 100%. Matched tumor tissues were available from 14 patients and 7 showed the PD-L1 TPS ≥50%. PD-L1 status on CTCs was not correlated with that on tumor tissues both using proportional score and H score (Spearman's correlation: r = 0.0007 and 0.08, respectively). On CTCs, patients with PD-L1 ≥50 % have significantly higher disease control rate than those with below 50% (83.3% versus 36.4%, p&lt;0.01). Similarly, patients with PD-L1 ≥50 % on CTC had significantly longer PFS compared with those with below 50% (293 days versus 49 days, hazard ratio 2.41 (95% CI: 1.05-5.54), p = 0.03). During nivolumab treatment, number of CTCs was decreased (median number was 10 at 4 weeks, and 5 at 8 weeks). Among those with PD-L1 ≥50 % on CTC at baseline, changes in number and PD-L1 status on CTCs at 4 weeks did not correlate with PFS.

Conclusions: Sequential monitoring of PD-L1 expression on CTCs during nivolumab treatment was successfully conducted. PD-L1 expression on CTCs at baseline was a strong predictor in efficacy. Predictive significance of PD-L1-positive CTCs should be evaluated in a larger validation cohort.

Citation Format: Yasuhiro Koh, Hiroaki Akamatsu, Keita Mori, Kuninobu Kanai, Atsushi Hayata, Nahomi Tokudome, Masayuki Higuchi, Keiichiro Akamatsu, Masanori Nakanishi, Hiroki Ueda, Nobuyuki Yamamoto. Predictive impact of sequential evaluation of PD-L1-expressing circulating tumor cells in NSCLC patients treated with nivolumab [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5595.

Athletes as Health Testing Examinees

Health-testing examination data of 91 male and 54 female athletes were studied, together with age-matched controls, on serum biochemistry, ECG findings, hematology, and some data on gynecological physiology. Analysis of serum biochemical values revealed statistically significant differences in 14 of 18 routine test items as compared with the age-matched controls. In ECG findings, the combination of bradycardia and left ventricular hypertrophy was most frequently found in male athletes, whereas that of bradycardia and sinus arrythmia was observed predominantly in female athletes. The incidence of anemia and menstrual dysfunction was higher in female athletes than in controls, especially in the basketball team. In the same team, a high rate of deviant ECG records and a different distribution of the age at menarche were also observed.

Abstract A056: Sequential tracking of PD-L1 expression on circulating tumor cells in NSCLC patients treated with nivolumab

Background: Nivolumab (anti-PD-1 antibody) has become a new standard treatment in pretreated, advanced non-small cell lung cancer (NSCLC). Although strong expression of PD-L1 on tumor tissue has predictive value, significance of its expression on circulating tumor cell (CTC) is unknown and its status can be changed during the treatment. Here, we conducted a serial evaluation of PD-1-expressing CTCs in NSCLC patients treated with nivolumab. Methods: Advanced NSCLC patients who receive nivolumab at Wakayama Medical University Hospital were enrolled in this prospective observational study (registered at UMIN (000024414)). Nivolumab was administered 3 mg/kg biweekly until progressive disease (PD) or unacceptable toxicity. Peripheral whole blood (3 mL) was collected in a EDTA collection tube (BD vacutainer) and processed within 3 hours for CTC evaluation at baseline, week 4, and week 8. CTCs were detected using microcavity array system (Hitachi Chemical Co.). PD-L1 expression was immunohistochemically examined on both tumor tissues and CTCs using anti-PD-L1 antibody, clone 28-8 (Abcam). Results: Thirty-eight patients were registered in this study between January 2016 and September 2016. Clinical characteristics of the patients were as follows: median age 68 (range, 49 to 86); male 73%; stage IV 100%; squamous/non-squamous, 30/65%. Regarding nivolumab treatment, overall response rate (ORR) was 22% (95% confidence interval (CI): 10-38%), and median progression-free survival (PFS) was 62 days (95%CI: 40-235 days). At baseline, CTCs were detected in all patients (median, 15; range, 1-90) and PD-L1-expressing CTCs were detected in 87% of patients. Tumor proportion score (TPS) of PD-L1 expression on CTCs varied from 6% to 100%. Matched tumor tissues were available from 14 patients and 7 showed the PD-L1 TPS ≥ 50%. PD-L1 status on CTCs was not correlated with that on tumor tissues both using proportional score and H score (Spearman’s correlation: r = 0.0007 and 0.08, respectively). On CTCs, patients with PD-L1 ≥ 50 have significantly higher disease control rate than those with below 50% (83.3% versus 36.4%, p&lt;0.01). Similarly, patients with PD-L1 ≥ 50% on CTC was significantly longer PFS compared with those with below 50% (293 days versus 49 days, hazard ratio 2.41 (95% CI: 1.05-5.54), p = 0.03). During nivolumab treatment, number of CTCs was decreased (median number was 10 at 4 weeks and 5 at 8 weeks). Among those with PD-L1 ≥ 50% on CTC at baseline, changes in number and PD-L1 status on CTCs at 4 weeks did not correlate with PFS. Conclusions: Serial monitoring of PD-L1 expression on CTCs during nivolumab treatment was successfully conducted. PD-L1 expression on CTCs at baseline was a strong predictor in efficacy. Predictive significance of PD-L1-positive CTCs should be also evaluated in validation cohort using pembrolizumab.

Citation Format: Hiroaki Akamatsu, Yasuhiro Koh, Keita Mori, Kuninobu Kanai, Atsushi Hayata, Nahomi Tokudome, Masayuki Higuchi, HIsashige Kanbara, Keiichiro Akamatsu, Masanori Nakanishi, Hiroki Ueda, Nobuyuki Yamamoto. Sequential tracking of PD-L1 expression on circulating tumor cells in NSCLC patients treated with nivolumab [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A056.

Abstract A057: Serial evaluation of multiple serum protein levels in non-small lung cancer patients treated with nivolumab

Background: Blockade of programmed death receptor-1 (PD-1) pathway is effective against various malignancies. Although PD-ligand 1 (PD-L1) expression on tumor tissue has been established as companion diagnostics in non-small cell lung cancer (NSCLC), additional biomarkers to enrich the patients likely to benefit from the therapy are critically needed. Here, we conducted a serial evaluation of multiple serum cytokines, growth factors, and angiogenesis factors relevant to immune checkpoint blockade in NSCLC patients treated with nivolumab. Patients and Methods: Advanced NSCLC patients after failure of at least one prior chemotherapy regimen received nivolumab monotherapy (3mg/kg, q2W) until progressive disease (PD) or unacceptable toxicity. Serum samples were collected in a serum separation tube (Venoject II autosep, TERUMO) at baseline and at week 4. Best response was classified into partial response (PR), stable disease (SD), or progressive disease (PD) according to RECIST v1.1. Using LuminexTM xMapTM technology, serum levels of 54 proteins consisting of cytokines, chemokines, growth factors, and angiogenesis factors were analyzed. All statistical analyses were carried out using JMP Pro software (ver. 13.0) and Mann-Whitney U test and Spearman's test were performed accordingly. A p value &lt;0.05 was considered as significant. Results: Thirty-eight patients were registered in the study between January 2016 and March 2017 at Wakayama Medical University Hospital and 34 were included in the analysis. Demographics of the patients were as follows: median age 68 (range, 49 to 86); male 73 %; stage IV, 100%; squamous/non-squamous, 30/70 %. Overall response rate was 22% (7/34), and disease control rate was 53% (18/34). Among 54 serum proteins measured serially, the levels of serum IL-8 and TNF-α were significantly lower at baseline in non-PD patients than in PD patients (p &lt; 0.01 in both cases). In addition, the levels of both serum IL-8 and TNF-α were correlated with longer progression-free survival (PFS) (r=-0.4695 and -0.5912, respectively). It is noteworthy that serum IL-8 levels at week 4 in PR patients were significantly lower than those in non-PR patients (p &lt;0.01). Correlation between IL-8 levels at week 4 and longer PFS was shown to be more significant (r=-0.6864). Serum VEGF-A levels were significantly lower in PR patients than those in non-PR patients at week 4 (p &lt;0.05). Conclusions: We identified the serum levels of IL-8, TNF-α, and VEGF-A as potential biomarkers to predict clinical benefit from nivolumab treatment in advanced NSCLC by multi-analyte protein-based assay. Incorporating serum TNF-α levels may have potential to improve the patient enrichment in addition to previously reported potential biomarkers such as IL-8 and VEGF levels. Further evaluation is warranted in a larger cohort to validate the findings.

Citation Format: Jun Oyanagi, Yasuhiro Koh, Hiroaki Akamatsu, Kuninobu Kanai, Atsushi Hayata, Nahomi Tokudome, keiichiro Akamatsu, Masanori Nakanishi, Hiroki Ueda, Nobuyuki Yamamoto. Serial evaluation of multiple serum protein levels in non-small lung cancer patients treated with nivolumab [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A057.

Abstract 3778: PD-L1 expression on circulating tumor cells and its comparison with tumor tissues in Japanese lung cancer patients

Background: Blockade of programmed death receptor-1 (PD-1) pathway is effective against solid tumors including lung cancer. Although PD-ligand 1 (PD-L1) expression on tumor tissue is expected as a potent predictive biomarker, its detection remains challenging due to its dynamic and unstable status. Circulating tumor cells (CTCs) have potential as an alternative material for non-invasive and real-time diagnosis. Here, we evaluated the PD-L1 expression on CTCs in patients with lung cancer and investigated the agreement between tumor tissues and CTCs.

Material and methods: CTCs were captured and immune-stained using microcavity array system. CTCs were defined as those positive for DAPI and cytokeratin (CK) and negative for CD45. PD-L1 expression on CTCs was evaluated by addition of the process of PD-L1 immunocytochemistry. For CTCs detection, 3 ml of peripheral whole blood was collected from the patients who consented in written form and PD-L1 immunohistochemistry was performed using corresponding tumor tissues.

Results: Sixty-seven lung cancer patients were enrolled in the study between July 2015 and April 2016 at Wakayama Medical University. Patient characteristics were as follows: median age 71 (range, 39 to 86); male 72%; stage II-III/IV, 15/85%; non-small cell lung cancer (NSCLC)/small cell lung cancer (SCLC)/Other, 73/21/6%. CTCs were detected in 66 out of 67 patients (median 19; range, 0 to 115) and more than 5 CTCs were detected in 78% of patients. PD-L1-expressing CTCs were detected in 73% of patients and the proportion score (PS) of PD-L1-expressing CTCs ranged from 3% to 100%, suggesting intra-patient heterogeneity of PD-L1 expression on CTCs. Significantly more PD-L1-expressing CTCs were detected in patients without EGFR mutations than those with EGFR mutations (P = 0.0433). Tumor tissues were available from 28 patients and were immune-stained for PD-L1. Seven showed the PS of PD-L1-expressing tumor cells &lt; 1%, 11 showed 1-49%, and 10 showed ≥ 50%. No positive correlation was observed on PD-L1 expression between tumor tissues and CTCs based on PS (R2 = 0.0034). Three adenocarcinoma cases with PD-L1-positive tumor tissue did not harbor any PD-L1-expressing CTCs and conversely, three adenocarcinoma cases with PD-L1-negative tumor tissue harbored PD-L1-expressing CTCs, showing the discrepancy between tumor tissues and CTCs. It is also noteworthy that SCLC patients had perfect agreement on PD-L1 expression between tumor tissues and CTCs.

Conclusions: PD-L1 expression was detectable on CTCs in lung cancer patients and intra-patient heterogeneity of its expression was observed. There was no agreement between tumor tissues and CTCs on PD-1 expression. Further investigation is warranted to better understand the clinical significance of PD-L1-expressing CTCs.

Citation Format: Hiroaki Akamatsu, Yasuhiro Koh, Satomi Yagi, Satoshi Kambayashi, Ayaka Tanaka, Kuninobu Kanai, Atsushi Hayata, Nahomi Tokudome, Keiichiro Akamatsu, Masayuki Higuchi, Hisashige Kanbara, Masanori Nakanishi, Hiroki Ueda, Nobuyuki Yamamoto. PD-L1 expression on circulating tumor cells and its comparison with tumor tissues in Japanese lung cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3778. doi:10.1158/1538-7445.AM2017-3778

Development of an automated size-based filtration system for isolation of circulating tumor cells in lung cancer patients

Circulating tumor cells (CTCs), defined as tumor cells circulating in the peripheral blood of patients with solid tumors, are relatively rare. Diagnosis using CTCs is expected to help in the decision-making for precision cancer medicine. We have developed an automated microcavity array (MCA) system to detect CTCs based on the differences in size and deformability between tumor cells and normal blood cells. Herein, we evaluated the system using blood samples from non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC) patients. To evaluate the recovery of CTCs, preclinical experiments were performed by spiking NSCLC cell lines (NCI-H820, A549, NCI-H23 and NCI-H441) into peripheral whole blood samples from healthy volunteers. The recovery rates were 70% or more in all cell lines. For clinical evaluation, 6 mL of peripheral blood was collected from 50 patients with advanced lung cancer and from 10 healthy donors. Cells recovered on the filter were stained. We defined CTCs as DAPI-positive, cytokeratin-positive, and CD45-negative cells under the fluorescence microscope. The 50 lung cancer patients had a median age of 72 years (range, 48–85 years); 76% had NSCLC and 20% had SCLC, and 14% were at stage III disease whereas 86% were at stage IV. One or more CTCs were detected in 80% of the lung cancer patients (median 2.5). A comparison of the CellSearch system with our MCA system, using the samples from NSCLC patients, confirmed the superiority of our system (median CTC count, 0 versus 11 for CellSearch versus MCA; p = 0.0001, n = 17). The study results suggest that our MCA system has good clinical potential for diagnosing CTCs in lung cancer.

Predictive impact of PD-L1-expressing circulating tumor cells in NSCLC patients treated with nivolumab

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Background: PD-L1 expression on tumor tissue is associated with response to PD-1 blockade in NSCLC. Here, we conducted a serial evaluation of PD-1-expressing circulating tumor cells (CTCs) as a potential real-time diagnostic modality in NSCLC patients treated with nivolumab. Methods: Advanced NSCLC patients after failure of at least one prior chemotherapy regimen received nivolumab monotherapy (3mg/kg, q2W) until progressive disease (PD) or unacceptable toxicity. Peripheral whole blood (3 mL) was collected for CTC evaluation at baseline and at week 4. CTCs were detected using microcavity array system (Hitachi Chemical Co., Ltd, Chikusei, Japan). PD-L1 expression was immunohistochemically examined on both tumor tissues and CTCs. This study was registered at UMIN (ID: 000024414). Results: Thirty patients were registered in the study between January 2016 and September 2016 at Wakayama Medical University Hospital and 29 were included in the analysis. Demographics of the patients were as follows: median age 70 (range, 49 to 86); male 73 %; stage IV, 100 %; squamous/non-squamous, 27/73 %. At baseline, CTCs were detected in all patients (median, 15; range, 1 to 90) and PD-L1-expressing CTCs were detected in 87% of patients. Tumor proportion score (TPS) of PD-L1 expression on CTCs ranged from 6% to 100%, indicating intrapatient heterogeneity. Matched tumor tissues were available from 14 patients and 7 showed the PD-L1 TPS ≥ 50%. No positive correlation was observed on PD-L1 expression between tumor tissues and CTCs based on TPS (R2 = 0.0035). Overall response rate was 25% (7/29), and disease control rate was 54% (15/29). Total CTC count was significantly decreased after nivolumab treatment at week 4 (p < 0.05), but no significant change was observed in PD-L1 TPS on CTC. Patients harboring CTCs with PD-L1 TPS 50% or more at baseline were significantly more likely to achieve non-PD than those harboring CTCs with TPS less than 50% (p < 0.05). Conclusions: This is the first report on a serial monitoring of PD-L1 expression on CTCs in patients treated with nivolumab. PD-L1-expressing CTCs are suggested to hold potential for predicting clinical benefit. Clinical trial information: 000024414.

Applicability of the Japanese equation for estimating glomerular filtration rate in patients with advanced-stage thoracic cancer

BACKGROUND

The 24-h creatinine clearance (24-h Ccr) and the Cockcroft-Gault equation (CG) are commonly used as markers of renal function in clinical practice. However, the utility of the Japanese equation for estimating glomerular filtration rate (eGFR) in cancer patients has not yet been evaluated. The aim of this cross-sectional study was to investigate the extent and correlating factors for differences between eGFR and both 24-h Ccr and CG in advanced-stage thoracic cancer patients.

METHODS

eGFR, 24-h Ccr, and CG were calculated in 90 patients with thoracic malignancies. We evaluated how these three parameters are affected by clinical factors, including age, body surface area, serum creatinine concentration, and body mass index.

RESULTS

eGFR and CG were significantly correlated with 24-h Ccr (r=0.64, p<0.001 and; r=0.67, p<0.001, respectively). However, the median value derived from eGFR was higher than the median 24-h Ccr and the CG value (74.0, 65.2, and 63.9mL/min, respectively). Age had a significant positive correlation with the differences between eGFR and both 24-h Ccr and CG value (r=0.30, p=0.005 and; r=0.47, p<0.001, respectively). The differences between eGFR and the other two parameters were significantly higher in older patients (age≥70 years) than in younger patients (age<70 years) (p=0.023, p<0.001, respectively).

CONCLUSIONS

eGFR is likely to overestimate the renal function of elderly cancer patients. A modified equation for evaluating the renal function of Japanese older patients might be needed.

Abstract 2257: Differential expression of PD-L1 on circulating tumor cells among patients with advanced lung cancer

Background and purpose:

Immune-checkpoint blockade with anti-programmed death-1 (PD-1) antibodies is rapidly emerging for the treatment of human malignancies including lung cancer. Although programmed death-ligand 1 (PD-L1) has been studied as a predictive biomarker, detection and evaluation of PD-L1 expression level on tissue samples remain challenging due to its dynamic and unstable expression. Thus the diagnostic tool for real-time monitoring of PD-L1 expression is critically needed. Here, we assessed the expression pattern of PD-L1 on circulating tumor cells (CTCs) by using microcavity array (MCA) system in patients with advanced non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC).

Experimental procedure:

PD-L1 staining on CTCs was established using NSCLC cell lines H820, H441, A549 and H23 expressing varying levels of PD-L1 spiked in the peripheral blood obtained from healthy donors. For clinical evaluation, 3 ml of peripheral whole blood was collected from 20 advanced lung cancer patients prior to the initiation of chemotherapy and from 10 healthy donors. Cells were captured and immuno-stained by using the automated MCA system (Hitachi Chemical Co., Ltd). CTCs were defined as those positive for DAPI and cytokeratin (CK) and negative for CD45. PD-L1 expression level on CTCs was visualized by addition of PD-L1 immunocytochemistry procedure. High-resolution fluorescent images were obtained using fluorescence microscope (Carl Zeiss Microscopy Co., Ltd).

Results:

Characteristics of 20 lung cancer patients enrolled in clinical study were as follows: median age 74 (range, 48 to 84); male 60%; stage III/IV, 10/90%; NSCLC/SCLC, 70/30%. More than 2 CTCs were identified in 14 patients (median 22.5; range, 4 to 71), and PD-L1 positive CTCs were detected in 12 patients (median 5; range, 2 to 15). No correlation was detected between the number of total CTCs and that of PD-L1 positive CTCs in each patient (R2 = 0.05). We found a total of 25 CTC clusters from 20 patients, of which PD-L1 expression was both homogenous and heterogeneous. It is noteworthy that clustered CTCs have larger proportion of PD-L1 positive CTCs per whole clustered CTCs than that of non-clustered CTCs (24/54, 44% versus 51/347, 15%, respectively). We further focused on CTC-interacting white blood cells, which intensively bound with aggregated CTCs rather than single CTC (12/54, 22% versus 43/337, 13%, respectively). Our data implicate that PD-L1 expression on CTC correlates with aggregation of CTCs (p &lt; 0.05).

Conclusions:

Our results showed that PD-L1 expression on CTCs was detectable and there is intrapatient heterogeneity of its expression in patients with advanced lung cancer. Further investigation is warranted to better understand the biological importance of the correlation between PD-1 expression and CTC aggregation and CTC bound to white blood cells.

Citation Format: Woong Kim, Yasuhiro Koh, Hiroaki Akamatsu, Satomi Yagi, Ayaka Tanaka, Kuninobu Kanai, Atsushi Hayata, Ryota Shibaki, Masayuki Higuchi, Hisashige Kanbara, Takashi Kikuchi, Keiichiro Akamatsu, Masanori Nakanishi, Hiroki Ueda, Nobuyuki Yamamoto. Differential expression of PD-L1 on circulating tumor cells among patients with advanced lung cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2257.

Cigarette smoke augments MUC5AC production via the TLR3-EGFR pathway in airway epithelial cells

BACKGROUND

Viral infections are a major cause of chronic obstructive pulmonary disease (COPD) exacerbations. Toll-like receptor 3 (TLR3) reacts with double-stranded RNA (dsRNA) and participates in the immune response after viral infection. In the present study, we examined whether cigarette smoke, which is involved in the pathogenesis of COPD, enhances mucin production via the TLR3-epidermal growth factor receptor (EGFR) pathway in airway epithelial cells.

METHODS

We studied the effects of cigarette smoke extract (CSE) on signal transduction and the production of mucin 5AC (MUC5AC) in NCI-H292 cells and differentiated primary human bronchial epithelial cells stimulated with a synthetic dsRNA analogue, polyinosinic-polycytidylic acid [poly(I:C)], used as a TLR3 ligand.

RESULTS

CSE significantly potentiated the production of MUC5AC in epithelial cells stimulated with poly(I:C). Antibodies to EGFR or EGFR ligands inhibited CSE-augmented MUC5AC release in poly(I:C)-treated cells. Treatment with poly(I:C) or CSE alone increased the phosphorylation of EGFR and extracellular signal-regulated kinase (ERK). However, after poly(I:C) stimulation, CSE did not enhance EGFR phosphorylation, but did augment ERK phosphorylation. EGFR inhibitors and an ERK inhibitor inhibited the augmented release of MUC5AC. In addition, treatment with N-acetylcysteine, an antioxidant, inhibited the CSE-augmented phosphorylation of ERK and MUC5AC.

CONCLUSIONS

These data show that cigarette smoke increases TLR3-stimulated MUC5AC production in airway epithelial cells, mainly via ERK signaling. The effect might be mediated in part by oxidative stress. Modulation of this pathway might be a therapeutic target for viral-induced mucin overproduction in COPD exacerbation.

TLR3 activation augments matrix metalloproteinase production through reactive nitrogen species generation in human lung fibroblasts

Viral infection often triggers asthma exacerbation and contributes to airway remodeling. Cell signaling in viral infection is mainly mediated through TLR3. Many mediators are involved in airway remodeling, but matrix metalloproteinases (MMPs) are key players in this process in asthma. However, the role of TLR3 activation in production of MMPs is unknown. In this study, we examined the effects of polyinosinic-polycytidylic acid [poly(I:C)], a ligand for TLR3, on production of MMPs in human lung fibroblasts, with a focus on nitrosative stress in TLR3 modulation of MMP production. After lung fibroblasts were treated with poly(I:C), production of MMP-1, -2, and -9 and inducible NO synthase (iNOS) was assessed. The roles of NF-κB and IFN regulatory factor-3 (IRF-3) in the poly(I:C)-mediated production of MMPs and the responsiveness to poly(I:C) of normal lung fibroblasts and asthmatic lung fibroblasts were also investigated. Poly(I:C) augmented production of MMPs and iNOS in fibroblasts, and an iNOS inhibitor diminished this production of MMPs. Poly(I:C) stimulated translocation of NF-κB and IRF-3 into the nucleus in fibroblasts and inhibition of NF-κB or IRF-3 abrogated the poly(I:C)-induced increase in both iNOS expression and release of MMPs. Poly(I:C)-induced production of iNOS and MMPs was greater in asthmatic fibroblasts than in normal fibroblasts. We conclude that viral infection may induce nitrosative stress and subsequent MMP production via NF-κB- and IRF-3-dependent pathways, thus potentiating viral-induced airway remodeling in asthmatic airways.

Neuromuscular transmission is not impaired in axonal Guillain--Barré syndrome

BACKGROUND

Previous studies have shown that anti-GQ1b antibodies induce massive neuromuscular blocking. If anti-GM1 and -GD1a antibodies have similar effects on the neuromuscular junction (NMJ) in human limb muscles, this may explain selective motor involvement in axonal Guillain--Barré syndrome (GBS).

METHODS

Axonal-stimulating single-fibre electromyography was performed in the extensor digitorum communis muscle of 23 patients with GBS, including 13 with the axonal form whose sera had a high titre of serum IgG anti-GM1 or -GD1a antibodies.

RESULTS

All patients with axonal or demyelinating GBS showed normal or near-normal jitter, and no blocking.

CONCLUSION

In both axonal and demyelinating GBS, neuromuscular transmission is not impaired. Our results failed to support the hypothesis that anti-GM1 or -GD1a antibody affects the NMJ. In GBS, impulse transmission is presumably impaired in the motor nerve terminal axons proximal to the NMJ.

POEMS syndrome with Guillan-Barre syndrome-like acute onset: a case report and review of neurological progression in 30 cases

POEMS (polyneuropathy, organomegaly, endocrinopathy, M-protein and skin changes) syndrome is a rare cause of demyelinating neuropathy with monoclonal plasma cell proliferation, and POEMS neuropathy is usually chronically progressive. Herein, the authors report a 34-year-old woman with POEMS syndrome presenting as acute polyneuropathy. Within 2 weeks of disease onset, she became unable to walk with electrodiagnostic features of demyelination and was initially diagnosed as having Guillan-Barré syndrome. Other systemic features (oedema and skin changes) developed later, and an elevated serum level of vascular endothelial growth factor led to the diagnosis of POEMS syndrome. She received high-dose chemotherapy with autologous peripheral blood stem cell transplantation, resulting in good recovery. The authors also reviewed patterns and speed of progression of neuropathy in the 30 patients with POEMS syndrome; 22 (73%) of them were unable to walk independently with the median period of 9.5 months from POEMS onset (range 0.5-51 months). Whereas the speed of neuropathy progression varies considerably among patients, some POEMS patients can show acute or subacute polyneuropathy. The early diagnosis and treatment could result in rapid improvement as shown in the present patient.

Prevalence of intestinal parasites and genotyping of Giardia intestinalis in pet shop puppies in east Japan

The current study examined the prevalence of intestinal parasites and genotypes of Giardia intestinalis in puppies from nine pet shops in east Japan. Fresh fecal samples from 1794 puppies (≦3 months old) were collected on one occasion. Giardia spp. was examined for specific coproantigen using ELISA kit (SNAP®Giardia, IDEXX Laboratories, Inc., USA). Other intestinal parasites were detected microscopically using the formalin-ethyl acetate sedimentation technique. Genotyping was determined for the random 29 stool samples identified as Giardia spp. positive using PCR and direct sequencing of the glutamate dehydrogenase (gdh) gene. Overall prevalence of protozoan Giardia spp. and Cystoisospora spp. revealed 23.4% and 11.3%, respectively. Prevalence of ascarids, Strongyloides spp. and hookworms were recorded 1.8%, 1.1% and 0.1%, respectively. Protozoan Giardia spp. and Cystoisospora spp., thus, represent important pathogens among pet shop puppies. All genotyped G. intestinalis isolates were belonged to assemblage C or D, identified as dog-specific genotypes. Zoonotic assemblage A and B were not demonstrated. The result suggests that the risk of zoonotic transmission of G. intestinalis from pet shops puppies to humans may be quite low in Japan.