Ayaka Tanaka

Progression of Irreversible Airflow Limitation in Asthma: Correlation with Severe Exacerbations

BACKGROUND Severe exacerbations of asthma are periods of excess functional and pathological changes in the airways that have been proposed to induce airway remodeling. OBJECTIVE The objective of this study was to explore whether severe exacerbations are correlated with the decline in post-bronchodilator forced expiratory volume in 1 second (FEV1) and loss of bronchodilator reversibility (BDR). METHODS We examined the changes in FEV1 and BDR in 140 nonsmoking patients with well-controlled asthma at baseline and correlated these changes with the frequency of severe asthma exacerbations. RESULTS A 3-year follow-up assessment was completed in 128 patients. A total of 28 (21.9%) patients experienced at least 1 severe exacerbation with a mean rate of 0.16 year(-1). The exacerbation rate was significantly correlated with an annual rate of decline in FEV1 (ρ = 0.49, P < .0001). Both patients with 1 exacerbation and those with 2 or more exacerbations had greater declines in FEV1 than patients with no exacerbations (no exacerbation, 13.6 mL/year; 1 exacerbation, 41.3 mL/year; 2 or more exacerbations, 58.3 mL/year; P < .01 and P < .0001, respectively). The changes in BDR from baseline to the end of the study in patients who did or did not experience an exacerbation were -1.2% and 0.1%, respectively (P < .0005). The changes in BDR were significantly correlated with the annual rates of change in FEV1 (r = 0.40, P < .0001). CONCLUSION The occurrence of severe exacerbations of asthma is correlated with the progression of irreversible airflow limitation over time. This suggests that asthma exacerbations could have the long-term adverse consequences of structural and functional changes in the airways.

Peripheral pulmonary carcinoid tumor diagnosed by endobronchial‐ultrasound‐guided bronchoscopy

A 45‐year‐old Japanese woman complained of uncontrolled hypertension and face swelling. She was diagnosed with Cushings syndrome with secretion of adrenocorticotropic hormone. Fluorodeoxyglucose positron emission tomography‐computed tomography revealed a 2 × 2 cm mass in her left lung, with high standardized maximum uptake value. She underwent bronchoscopy with endobronchial ultrasound via a guide‐sheath. Surgical resection of her left upper lung was performed, and pathological examination showed a typical carcinoid tumor. After lung resection, she recovered from her subjective symptoms. Diagnosis of peripheral carcinoid tumor of the lung is generally difficult. Here, we introduce a case of peripheral pulmonary carcinoid tumor diagnosed by endobronchial‐ultrasound‐guided bronchoscopy.

Abstract 4149: Increased migration ability of osimertinib-resistant EGFR-T790M mutant non-small-cell lung cancer cells

Background: A third generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) osimertinib is effective against gefitinib/erlotinib-resistant non-small-cell lung cancer (NSCLC) harboring EGFR T790M mutation. Although the majority of these patients initially responds to osimertinib, they eventually develop resistance. Acquired mutations such as EGFR C797S mutation have been reported to confer resistance to osimertinib, but mechanisms of resistance to osimertinib or biological behaviors of osimertinib-resistant NSCLC have not been fully elucidated. Materials and methods: Osimertinib-resistant PC-9/ZD/OR1 and PC-9/ZD/OR3 cells were generated after continuous exposure of gefitinib-resistant PC-9/ZD cells harboring both EGFR exon 19 deletion and T790M mutations to increasing concentrations of osimertinib. Growth-inhibitory effect of inhibitors gefitinib and osimertinib was evaluated by MTT assay. Common EGFR mutational status was examined by RainDrop Digital PCR System (RainDance Technologies). Immunoblot analysis was performed to investigate the modulation of molecules relevant to EGFR signaling pathways. Cell-adhesion assay, wound closure assay and transwell assay were performed to evaluate the ability of cell adhesion and migration. Results: Both PC-9/ZD/OR1 and PC-9/ZD/OR3 cells showed 50- to 120-fold more resistant to osimertinib than parental PC-9/ZD cells, and maintained resistance to gefitinib as well. PC-9/ZD/OR cells maintain EGFR exon 19 deletion and T790M mutations and C797S mutation was not detected. Although phosphorylation of EGFR and ERK1/2 were inhibited by osimertinib treatment in PC-9/ZD/OR cells, phosphorylation of Akt was not inhibited. PC-9/ZD/OR cells express the elevated level of c-MET and its phosphorylated form, suggesting that bypass signaling is activated to evade EGFR pathway blockade. PC-9/ZD/OR cells also express marked level of E-cadherin which parental PC-9/ZD cells do not express. PC-9/ZD/OR cells exhibited enhanced adherent activity, cell motility and migration ability compared to PC-9/ZD cells. Notably, osimertinib treatment significantly reduced the number of migrated cells not only in PC-9/ZD cells but also in PC-9/ZD/OR cells. These results suggest that osimertinib-resistant PC-9/ZD/OR cells acquired enhanced migration ability through c-MET pathway activation and/or induction of E-cadherin. Osimertinib treatment may be still effective to inhibit cell migration, suggesting that cell migration and cell growth are driven by different signaling pathways in PC-9/ZD/OR cells. Conclusion: c-MET overexpression was suggested to confer resistance to osimertinib and the resistant cells exhibited enhanced cell migration. Continuative osimertinib treatment may be beneficial in preventing metastasis even after the failure and involvement of c-MET and E-cadherin in osimertinib resistance should be further investigated. Citation Format: Satoshi Kambayashi, Yasuhiro Koh, Maiha Ohyama, Ayaka Tanaka, Hiroaki Akamatsu, Nahomi Tokudome, Hiroki Ueda, Nobuyuki Yamamoto. Increased migration ability of osimertinib-resistant EGFR-T790M mutant non-small-cell lung cancer cells [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 4149. doi:10.1158/1538-7445.AM2017-4149

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 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.

Abstract 2244: Development of an automated device for size-based enrichment and isolation of circulating tumor cells in lung cancer patients

Background and Purpose: Circulating tumor cells (CTCs) are relatively rare cells defined as tumor cells circulating in the peripheral blood of patients with solid tumors. Diagnosis utilizing CTCs is expected to help guide decision-making for precision cancer medicine. We 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. Here we evaluated its performance using preclinical spike-in model and blood samples from non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC) patients. Material and method: The automated MCA system consists of components such as chambered cartridge containing micro metal filter, reagent and waste reservoirs, and peristaltic pump. To evaluate the recovery of CTCs, preclinical experiments using NSCLC cells, NCI-H820, A549, NCI-H441 and NCI-H23 spiked into peripheral whole blood from healthy volunteers were performed. For clinical evaluation, 6 mL of peripheral whole blood was collected from 50 advanced lung cancer patients prior to the initiation of chemotherapy and from 10 healthy donors. Samples were collected in an EDTA-containing tube and were processed within 3 hours of blood draw. Recovered cells on the filter were then fixed, permeabilized, and stained automatically and high-resolution fluorescent images were obtained using fluorescence microscope. We defined CTC as DAPI-positive, cytokeratin-positive and CD45-negative cell. Results: Results of the preclinical study showed that up to 90% of spiked-in tumor cells were recovered, confirming that the detection sensitivity by this automated device is on par with that by previous manual detection procedure. Demographics of 50 lung cancer patients enrolled in clinical study were as follows: median age 72 (range, 48 to 85); male 66%; stage III/IV 12/88%; NSCLC/SCLC 78/22%. Cells defined as CTC were detected in 2 cases out of 10 healthy volunteers, of which CTC count was 1 and 2 / 6 mL, respectively. Three or more CTCs were detected in 71% of patients with advanced lung cancer (39 out of 50) and five or more CTCs were detected in 52% of patients (26 out of 50) (median CTC count 13.5). Among stage IV NSCLC patients, patients with extrathoracic metastasis tend to have more CTCs than in those with intrathoracic metasitasis (median CTC count, 8 versus 4, p = 0.058). A head-to-head comparison between CellSearch system and our system was conducted in NSCLC patients, showing the superiority of our system (median CTC count, 0 versus 11.25, p = 0.0001, n = 17). Conclusions Our results suggest that the automated MCA device has a clinical potential for CTCs diagnosis towards precision medicine in lung cancer. This device also enables higher throughput owing to its automated procedure. Further clinical evaluation including the detection of PD-L1 expression will be performed in an expansion cohort. Citation Format: Satomi Yagi, Yasuhiro Koh, Hiroaki Akamatsu, Woong Kim, Ayaka Tanaka, Kuninobu Kanai, Atsushi Hayata, Ryota Shibaki, Masayuki Higuchi, Hisashige Kanbara, Takashi Kikuchi, Keiichiro Akamatsu, Masanori Nakanishi, Hiroki Ueda, Nobuyuki Yamamoto. Development of an automated device for size-based enrichment and isolation of circulating tumor cells in lung cancer patients. [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 2244.

Abstract B138: Evaluation of a novel automated device for size-based enrichment and isolation of CTCs in patients with advanced lung cancer

Circulating tumor cells (CTCs) are associated with prognosis of patients with advanced solid tumors including lung cancer and reflect characteristics of the respective primary tumor and its metastatic deposits. Assessment of CTCs is expected to improve effectiveness of anticancer therapy and to sophisticate our knowledge to cancer metastasis. We previously reported that detection of CTCs using microcavity array (MCA) system yielded the superior sensitivity than FDA-approved CellSearch system in patients with non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC). Here we developed the automated CTCs detection device and evaluated its performance using preclinical spike-in model and blood samples from NSCLC and SCLC patients. The feasibility study on the assessement of PD-L1 expression level was also performed. To evaluate the recovery of CTCs preclinically, NSCLC cells, H1975, A549, H441 and PC-14 were spiked into 6 mL of peripheral whole blood obtained from healthy volunteers. Then, cells were captured and immuno-stained by using automated MCA system. CTCs were defined as those positive for DAPI and cytokeratin (CK) and negative for CD45. Additionally, normal blood cells and cancer cells were distinguished according to their size. For clinical evaluation, 6 mL of peripheral whole blood was collected from 10 healthy donors and 30 advanced lung cancer patients prior to the initiation of chemotherapy. Head-to-head comparison with CellSearch system was also conducted. PD-L1 immunostaining was established in a preclinical spike-in study using NSCLC cell lines, H820, A549, H441, and H23 with varying PD-L1 expression levels and tested as an exploratory objective in a subset of patients enrolled in a clinical study. We confirmed that up to 90% of spiked-in tumor cells were recovered by the automated MCA system, suggesting that the detection sensitivity by this automated device is on par with that by previous detection procedure. Characteristics of 30 lung cancer patients in clinical study were as follows: median age 71 (range, 48 to 85); male 70%; stage III/IV 17/83%; NSCLC/SCLC 83/17%. Cells defined as CTC were detected in 2 cases out of 10 healthy volunteers, of which CTC count was 1 and 2 in 6 mL of peripheral blood, respectively. More than 2 CTCs were detected in 77% of patients with advanced lung cancer (n = 23/30) and more than 5 CTCs were detected in 50% of patients (n = 15/30) (median CTC count 5.5). Significantly more CTCs were detected by the automated MCA system than by CellSearch system. Among stage IV NSCLC patients, patients with extrathoracic metastasis tend to have more CTCs than in those without one (median CTC count, 8 versus 4, p = 0.058). No difference in CTC counts between NSCLC and SCLC was observed in this study cohort. PD-L1 expression was assessed in a subset of patients and intra-patient heterogeneity of PD-L1 staining among CTCs was observed in patients who harbor PD-L1-positive CTCs. Our results suggest that the automated MCA device for size-based enrichment and isolation of CTCs has a clinical potential for CTCs diagnosis towards precision medicine in lung cancer. This also enables us to deal with more samples owing to its automated procedure and higher throughput. Further clinical evaluation including PD-L1 expression will be performed in an expansion cohort and the biology of CTCs will be investigated utilizing this device. 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, Nobuyuki Yamamoto. Evaluation of a novel automated device for size-based enrichment and isolation of CTCs in patients with advanced lung cancer. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr B138.