Cough and sputum in long COVID are associated with severe acute COVID-19: a Japanese cohort study

BACKGROUND

Multiple prolonged symptoms are observed in patients who recover from acute coronavirus disease 2019 (COVID-19), defined as long COVID. Cough and sputum are presented by patients with long COVID during the acute and post-acute phases. This study aimed to identify specific risk factors for cough and sputum in patients with long COVID.

METHODS

Hospitalized patients with COVID-19 aged 18 years were enrolled in a multicenter cohort study at 26 medical institutions. Clinical data during hospitalization and patient-reported outcomes after discharge were collected from medical records, paper-based questionnaires, and smartphone apps.

RESULTS

At the 3-, 6-, and 12-month follow-ups, there were no differences in the incidence rates of wet and dry coughs. In contrast, the proportion of patients presenting sputum without coughing increased over time compared to those with sputum and coughing. Univariate analyses of cough and sputum at all follow-up visits identified intermittent mandatory ventilation (IMV), smoking, and older age as risk factors for prolonged symptoms. At the 12-month follow-up, persistent cough and sputum were associated with the characteristics of severe COVID-19 based on imaging findings, renal and liver dysfunction, pulmonary thromboembolism, and higher serum levels of LDH, KL-6, and HbA1C. The Kaplan-Meier curves showed that the severity of acute COVID-19 infection was correlated with prolonged cough and sputum production. Multivariable logistic regression analysis showed that IMV ventilator management were independent risk factors for prolonged cough and sputum at 12 months.

CONCLUSIONS

In a Japanese population with long COVID, prolonged cough and sputum production were closely associated with severe COVID-19. These findings emphasize that a preventive approach including appropriate vaccination and contact precaution and further development of therapeutic drugs for COVID-19 are highly recommended for patients with risk factors for severe infection to avoid persistent respiratory symptoms.

Comprehensive analysis of long COVID in a Japanese nationwide prospective cohort study

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread rapidly since 2019, and the number of reports regarding long COVID has increased. Although the distribution of long COVID depends on patient characteristics, epidemiological data on Japanese patients are limited. Hence, this study aimed to investigate the distribution of long COVID in Japanese patients. This study is the first nationwide Japanese prospective cohort study on long COVID.

METHODS

This multicenter, prospective cohort study enrolled hospitalized COVID-19 patients aged ≥18 years at 26 Japanese medical institutions. In total, 1200 patients were enrolled. Clinical information and patient-reported outcomes were collected from medical records, paper questionnaires, and smartphone applications.

RESULTS

We collected data from 1066 cases with both medical records and patient-reported outcomes. The proportion of patients with at least one symptom decreased chronologically from 93.9% (947/1009) during hospitalization to 46.3% (433/935), 40.5% (350/865), and 33.0% (239/724) at 3, 6, and 12 months, respectively. Patients with at least one long COVID symptom showed lower quality of life and scored higher on assessments for depression, anxiety, and fear of COVID-19. Female sex, middle age (41-64 years), oxygen requirement, and critical condition during hospitalization were risk factors for long COVID.

CONCLUSIONS

This study elucidated the symptom distribution and risks of long COVID in the Japanese population. This study provides reference data for future studies of long COVID in Japan.

Diagnostic and prognostic biomarkers for progressive fibrosing interstitial lung disease

No biomarkers have been identified in bronchoalveolar lavage fluid (BALF) for predicting fibrosis progression or prognosis in progressive fibrosing interstitial lung disease (PF-ILD). We investigated BALF biomarkers for PF-ILD diagnosis and prognosis assessment. Overall, 120 patients with interstitial pneumonia who could be diagnosed with PF-ILD or non PF-ILD were enrolled in this retrospective study. PF-ILD was diagnosed according to Cottin's definition. All patients underwent bronchoscopy and BALF collection. We evaluated blood and BALF parameters, high-resolution computed tomography (HRCT) patterns, and spirometry data to identify factors influencing PF-ILD diagnosis and prognosis. On univariate logistic analysis, age, sex, the BALF white blood cell fraction (neutrophil, lymphocyte, eosinophil, and neutrophil-to-lymphocyte ratio), BALF flow cytometric analysis (CD8), and an idiopathic pulmonary fibrosis/usual interstitial pneumonia pattern on HRCT were correlated with PF-ILD diagnosis. Multivariate logistic regression analysis revealed that sex (male), age (cut-off 62 years, area under the curve [AUC] 0.67; sensitivity 0.80; specificity 0.47), white blood cell fraction in BALF (NLR, neutrophil, and lymphocyte), and CD8 in BALF (cut-off 34.2; AUC 0.66; sensitivity, 0.74; specificity, 0.62) were independent diagnostic predictors for PF-ILD. In BALF, the NLR (cut-off 8.70, AUC 0.62; sensitivity 0.62; specificity 0.70), neutrophil count (cut-off 3.0, AUC 0.59; sensitivity 0.57; specificity 0.63), and lymphocyte count (cut-off 42.0, AUC 0.63; sensitivity 0.77; specificity 0.53) were independent diagnostic predictors. In PF-ILD patients (n = 77), lactate dehydrogenase (cut-off 275, AUC 0.69; sensitivity 0.57; specificity 0.78), Krebs von den Lungen-6 (cut-off 1,140, AUC 0.74; sensitivity 0.71; specificity 0.76), baseline forced vital capacity (FVC) (cut-off 1.75 L, AUC 0.71; sensitivity, 0.93; specificity, 0.46), and BALF neutrophil ratio (cut-off 6.0, AUC 0.72; sensitivity 0.79; specificity 0.80) correlated with death within 3 years. The BALF cellular ratio, particularly the neutrophil ratio, correlated with the diagnosis and prognosis of PF-ILD. These findings may be useful in the management of patients with interstitial pneumonia.

The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force

Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection.

Genetic mechanisms influencing COVID-19 susceptibility are not well understood. Here, the authors analyzed whole blood RNA-seq data of 465 Japanese individuals with COVID-19, highlighting thousands of fine-mapped variants affecting expression and splicing of genes, as well as the presence of COVID-19 severity-interaction eQTLs.

Inhibition of stearoyl-CoA desaturase 1 (SCD1) enhances the antitumor T cell response through regulating β-catenin signaling in cancer cells and ER stress in T cells and synergizes with anti-PD-1 antibody

Background

Understanding the mechanisms of non-T cell inflamed tumor microenvironment (TME) and their modulation are important to improve cancer immunotherapies such as immune checkpoint inhibitors. The involvement of various immunometabolisms has recently been indicated in the formation of immunosuppressive TME. In this study, we investigated the immunological roles of stearoyl-CoA desaturase 1 (SCD1), which is essential for fatty acid metabolism, in the cancer immune response.

Methods

We investigated the roles of SCD1 by inhibition with the chemical inhibitor or genetic manipulation in antitumor T cell responses and the therapeutic effect of anti-programmed cell death protein 1 (anti-PD-1) antibody using various mouse tumor models, and their cellular and molecular mechanisms. The roles of SCD1 in human cancers were also investigated by gene expression analyses of colon cancer tissues and by evaluating the related free fatty acids in sera obtained from patients with non-small cell lung cancer who were treated with anti-PD-1 antibody.

Results

Systemic administration of a SCD1 inhibitor in mouse tumor models enhanced production of CCL4 by cancer cells through reduction of Wnt/β-catenin signaling and by CD8⁺ effector T cells through reduction of endoplasmic reticulum stress. It in turn promoted recruitment of dendritic cells (DCs) into the tumors and enhanced the subsequent induction and tumor accumulation of antitumor CD8⁺ T cells. SCD1 inhibitor was also found to directly stimulate DCs and CD8⁺ T cells. Administration of SCD1 inhibitor or SCD1 knockout in mice synergized with an anti-PD-1 antibody for its antitumor effects in mouse tumor models. High SCD1 expression was observed in one of the non-T cell-inflamed subtypes in human colon cancer, and serum SCD1 related fatty acids were correlated with response rates and prognosis of patients with non-small lung cancer following anti-PD-1 antibody treatment.

Conclusions

SCD1 expressed in cancer cells and immune cells causes immunoresistant conditions, and its inhibition augments antitumor T cells and therapeutic effects of anti-PD-1 antibody. Therefore, SCD1 is an attractive target for the development of new diagnostic and therapeutic strategies to improve current cancer immunotherapies including immune checkpoint inhibitors.

A solitary pulmonary nodule caused by Mycobacterium avium with pleural effusion and pleuritis after transbronchial biopsy: a case report

BACKGROUND

Pleural effusion and pleuritis are uncommon manifestations of Mycobacterium avium complex pulmonary disease. Pleuritis caused by Mycobacterium avium complex pulmonary disease presenting as a solitary pulmonary nodule is extremely rare. The pathogenesis of Mycobacterium avium complex pleuritis has not been elucidated. However, it has been suggested that secondary spontaneous pneumothorax from Mycobacterium avium complex pulmonary disease is one of the causes of Mycobacterium avium complex pleuritis.

CASE PRESENTATION

A 67-year-old Japanese woman who presented with a solitary pulmonary nodule developed a transient pneumothorax after transbronchial biopsy. A definitive diagnosis of solitary pulmonary nodule could not be made on bronchoscopy, so video-assisted thoracoscopic surgery was performed 1 month after bronchoscopy. On the day of hospitalization for the procedure, a left-sided pleural effusion appeared on a chest radiograph. Thickening of the parietal and visceral pleura and numerous scattered white small granules were seen on thoracoscopy. Histologic examination of the resected left lower lobe and a biopsy of the parietal pleura showed Mycobacterium avium complex solitary pulmonary nodule and Mycobacterium avium complex pleuritis.

CONCLUSION

Iatrogenic pneumothorax can be a cause of pleuritis in a patient with Mycobacterium avium complex pulmonary disease. Clinicians should watch for the appearance of secondary pleuritis after transbronchial biopsy even in a patient with localized disease such as Mycobacterium avium complex solitary pulmonary nodule.

Trends of concerns from diagnosis in patients with advanced lung cancer and their family caregivers: A 2-year longitudinal study

BACKGROUND

Both advanced cancer patients and their family caregivers experience distress and have a range of concerns after cancer diagnosis. However, longitudinal studies on this topic have been lacking.

AIM

To investigate concerns in both patients with advanced lung cancer and their family caregivers longitudinally from diagnosis.

DESIGN

A multi-center prospective questionnaire-based study.

SETTING/PARTICIPANTS

We recruited patients with newly diagnosed advanced lung cancer and their family caregivers at 16 hospitals in Japan. We prospectively assessed the prevalence of their concerns using the Concerns Checklist and investigated the associations between their concerns and mental status as well as quality of life until 24 months after diagnosis.

RESULTS

A total of 248 patients and their 232 family caregivers were enrolled. The prevalence of serious concerns was highest at diagnosis (patients: 68.3%, family caregivers: 65.3%). The most common serious concern was concern about the future in both groups at diagnosis (38.2% and 40.5%, respectively) and this remained high in prevalence over time, while the high prevalence of concern about lack of information improved 3 months after diagnosis in both groups. Approximately one-third of patient-family caregiver dyads had discrepant reports of serious concerns. The presence of serious concerns was significantly associated with anxiety and depression continuously in both groups.

CONCLUSIONS

The majority of advanced lung cancer patients and their family caregivers have serious concerns from diagnosis, which is associated with their psychological distress. The spectrum of concerns alters over the disease trajectory, warranting efficient tailored care and support for both groups immediately after diagnosis.

An Adult Case of Pulmonary Artery Sling Accompanied by Tracheobronchomalacia

Pulmonary artery (PA) sling is a congenital disease in which the left PA abnormally arises from the right PA and is usually diagnosed during the infantile period. We present an adult case of PA sling accompanied by tracheobronchomalacia found in a 49-year-old woman with a history of recurrent pneumonia. Computed tomography of the chest showed that the left lung was nourished by two aberrant PAs. Bronchoscopy demonstrated achondroplasia of the trachea and the right bronchus, which we speculate to have resulted in their stenosis. The recurrent pneumonia was attributable to these tracheobronchial structural abnormalities; we therefore stress the importance of focusing on the anatomic abnormalities in such cases.

Real-world Efficacy and Safety of Nivolumab for Advanced Non-Small-cell Lung Cancer: A Retrospective Multicenter Analysis

BACKGROUND

Nivolumab, an immune checkpoint inhibitor, is now a standard treatment for previously treated advanced non-small-cell lung cancer based on the results from phase III clinical trials. We evaluated the real-world efficacy and safety of nivolumab in a nonselected population and identified the clinical characteristics that influence efficacy.

MATERIALS AND METHODS

A total of 142 patients with advanced non-small-cell lung cancer who were administered nivolumab at Keio University and affiliated hospitals in Japan from January to July 2016 were enrolled. The treatment efficacy and adverse events were retrospectively reviewed, and the clinical characteristics associated with the nivolumab response were evaluated using univariate and stratified analyses and the Cochran-Mantel-Haenszel test.

RESULTS

The objective response rate was 17.0% (95% confidence interval [CI], 12.0%-24.0%), the median progression-free survival (PFS) was 58 days (95% CI, 50-67 days), and the proportion of patients with adverse events of any grade was 45.0%. EGFR/ALK mutation status was inversely associated with the treatment response (P < .05), and the difference in PFS for the mutation-positive versus mutation-negative patients was statistically significant (49 vs. 63 days; hazard ratio, 1.9; 95% CI, 1.1-5.2; P = .029). Previous radiotherapy also had a positive association with the treatment response (P = .012).

CONCLUSION

The objective response rate, PFS, and adverse event profiles were comparable to those observed in previous clinical trials. EGFR/ALK mutation-negative status and previous radiotherapy might be key clinical characteristics associated with a positive treatment response. Our findings could aid in the efficient immunotherapeutic management of lung cancer.

Erlotinib as second- or third-line treatment in elderly patients with advanced non-small cell lung cancer: Keio Lung Oncology Group Study 001 (KLOG001)

The aim of this study was to assess the efficacy and safety of erlotinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), as second- or third-line treatment for elderly Japanese patients with non-small-cell lung cancer (NSCLC). The patients eligible for this phase II trial were aged ≥70 years, had stage III/IV or recurrent NSCLC, and had previously received 1 or 2 chemotherapy regimens that did not include EGFR-TKIs. The patients received erlotinib at a dose of 150 mg/day. The primary endpoint was overall response rate (ORR), and the secondary endpoints were progression-free survival (PFS), overall survival (OS) and toxicity. A total of 38 patients with a median age of 76 years were enrolled. The majority of the patients were men (66%), had an Eastern Cooperative Oncology Group performance status of 1 (58%), stage IV disease (66%) and adenocarcinoma (74%). Of the 35 patients, 13 (34%) had tumors with EGFR mutations. The ORR was 26.3% (95% confidence interval: 12.1-40.5%) and the disease control rate was 47.4%. The median PFS was 3.7 months and the median OS was 17.3 months. The grade 3 adverse events observed included rash (13%), diarrhea (5%), interstitial pneumonitis (5%), anorexia (3%) and gastrointestinal bleeding (3%). Grade 4 or 5 adverse events were not observed. The median OS did not differ significantly between patients aged <75 years (14.9 months) and those aged ≥75 years (19.0 months; P=0.226). Therefore, erlotinib was found to be effective and well-tolerated in elderly patients with previously treated NSCLC.

Intimal Sarcoma of the Pulmonary Artery Treated with Pazopanib

Intimal sarcoma is a rare disease with a poor prognosis. We herein report the case of a 71-year-old man with intimal sarcoma of the pulmonary artery treated with pazopanib. The tumor showed regression after 1 month of treatment. Hand-foot syndrome led to cessation of pazopanib, which triggered a disease flare. Pazopanib should be considered in patients with intimal sarcoma of the pulmonary artery that is unresectable or recurrent after surgery or cytotoxic chemotherapy. We must be careful about drug cessation, as it can lead to a disease flare.

A phase II study of biweekly paclitaxel and carboplatin in elderly patients with advanced non-small cell lung cancer

PURPOSE

The number of elderly patients with advanced non-small cell lung cancer (NSCLC) is increasing. Although several studies have suggested the benefit of chemotherapy with a platinum doublet for elderly patients with advanced NSCLC, this treatment is still controversial in this age group. To evaluate the efficacy and tolerability of combination chemotherapy with biweekly paclitaxel and carboplatin for elderly patients with advanced NSCLC, we conducted a multicenter, non-randomized, open label, phase II trial.

METHODS

We recruited patients aged ≥70 years with clinical stage IIIB and IV NSCLC and ECOG performance status (PS) of 0-2. Patients received paclitaxel (90 mg/m(2)) and carboplatin (AUC = 2.5) on day 1 and 15, every 4 weeks. The primary endpoint was overall response rate (ORR), and the secondary endpoints were progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Sixty-five patients (median age 79 years; range 70-87 years) were enrolled. Forty-nine patients were men, and 48 were stage IV. The PS was 0, 1, and 2 in 28, 33, and 4 patients, respectively. The histological type of NSCLC was non-squamous in 69.3 % and squamous cell carcinoma in 30.7 % of patients. The median number of treatment cycles was 3 (range 1-6). The response rate was 29.4 % (95 % CI 18.7-43.0), and the disease control rate was 78.0 % (95 % CI 64.8-87.2). Median PFS and OS were 3.8 months (95 % CI 1.9-5.3) and 17.3 months (95 % CI 10.4-25.1), respectively. The most common grade 3 or 4 toxicities were neutropenia (27 %), leukopenia (15 %), infection (10 %), and anemia (8 %).

CONCLUSION

The combination of biweekly paclitaxel and carboplatin was effective and well tolerated in elderly patients with advanced NSCLC.

FOXD1 expression is associated with poor prognosis in non-small cell lung cancer

AIM

Clinical microarray datasets were analyzed to search for new therapeutic targets and prognostic markers of non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Microarray datasets from 90 lung cancer specimens, were analyzed with focus on the FOXD1 gene. Levels of FOXD1 mRNA were assessed in lung cancer cell lines and these levels were correlated with survival.

RESULTS

FOXD1-knockdown led to suppression of cell proliferation. Moreover, patients with high FOXD1 expression survived for a significantly shorter time than those with low FOXD1 expression.

CONCLUSION

The expression status of FOXD1 is a novel prognostic factor and may lead to new treatment strategies for NSCLC.

Methylation-induced downregulation of TFPI-2 causes TMPRSS4 overexpression and contributes to oncogenesis in a subset of non-small-cell lung carcinoma

We identified transmembrane protease, serine 4 (TMPRSS4) as a putative, druggable target by screening surgically resected samples from 90 Japanese non-small-cell lung cancer (NSCLC) patients using cDNA microarray. TMPRSS4 has two druggable domains and was upregulated in 94.5% of the lung cancer specimens. Interestingly, we found that TMPRSS4 expression was associated with tissue factor pathway inhibitor 2 (TFPI-2) expression in these clinical samples. In contrast to TMPRSS4, TFPI-2 expression was downregulated in NSCLC samples. The in vitro induction of TFPI-2 in lung cancer cell lines decreased the expression of TMPRSS4mRNA levels. Reporter assay showed that TFPI-2 inhibited transcription of TMPRSS4, although partially. Knockdown of TMPRSS4 reduced the proliferation rate in several lung cancer cell lines. When lung cancer cell lines were treated with 5-aza-2′-deoxycytidine or trichostatin A, their proliferation rate and TMPRSS4mRNA expression levels were also reduced through the upregulation of TFPI-2 by decreasing its methylation in vitro. The TFPI-2 methylation level in the low TMPRSS4 group appeared to be significantly low in NSCLC samples (P = 0.02). We found a novel molecular mechanism that TFPI-2 negatively regulates cell growth by inhibiting transcription of TMPRSS4. We suggest that TMPRSS4 is upregulated by silencing of TFPI-2 through aberrant DNA methylation and contributes to oncogenesis in NSCLC.

Abstract 5652: Activation of FGF2-FGFR1 pathway in EGFR-mutant lung cancer cell line with long-term gefitinib exposure

Many of the patients with non-small cell lung cancer (NSCLC) with sensitive epidermal growth factor receptor (EGFR)-mutation who initially responded well to EGFR-tyrosine kinase inhibitors (TKIs) eventually relapse. In spite of many studies over the last few years to elucidate this mechanism of acquired resistance to EGFR-TKIs, approximately 30% of the mechanisms of acquired resistance are still unknown. Recently autocrine signaling of fibroblast growth factors (FGFs) and their receptors (FGFRs) has been demonstrated in NSCLC cell lines. And several studies suggest that the FGF-FGFR autocrine growth pathway could be an important mechanism for intrinsic resistance to EGFR-TKIs in NSCLC cell lines with wild-type EGFR. But until now, no report has clarified the role of FGF-FGFR pathway in acquired resistance to EGFR-TKIs in NSCLC cell lines with sensitive EGFR mutations. We have established a gefitinib-resistant cell line (PC9 GR), by serial exposure of gefitinib to PC9, an originally gefitinib-sensitive lung cancer cell line (PC9 na). We confirmed that these cell lines did not harbor two well-known EGFR-TKI resistance mechanisms, the second mutation in the EGFR gene itself, EGFR T790 and the amplification of the MET oncogene. We collected total RNA from both PC9 na and PC9 GR and examined mRNA expression profile, by using cDNA microarray analysis. We found the expressions of FGFR1 and FGF2 were increased in PC9 GR compared to in PC9 na. The growth of PC9 GR cells was inhibited either by PD173074 (inhibitors of FGFRs) or knocking down of FGFR1 or FGF2 by siRNA in combination with gefitinib. FACS analysis revealed that the combination treatment with PD173074 and gefitinib induced apoptosis more efficiently in PC9 GR cells compared to gefitinib alone. PC9 na cells and PC9 GR cells did not show any change in the proportion of apoptotic cells after treatment with PD173074 alone. To further investigate how FGF2-FGFR1 pathway affects resistance to gefitinib in these cell lines, the downstream targets of EGFR signaling including the MEK-ERK and PI3K-AKT pathways were examined. In PC9 na cells, the phosphorylation of EGFR, ERK, and AKT was efficiently inhibited by gefitinib alone. On the other hand, in PC9 GR cells, the phosphorylation of ERK and AKT was not efficiently inhibited by gefitinib alone. However, the inhibition of phosphorylation of ERK was completely and AKT was less efficiently rescued by gefitinib and PD173074 combination therapy. In conclusion, these data suggest the activation of FGF2-FGFR1 signaling pathway contributes to the gefitinib resistance in PC9 GR. FGF2-FGFR1 pathway will be a therapeutic target for a subset of NSCLC that acquires EGFR-TKI resistance.

Citation Format: Hideki Terai, Kenzo Soejima, Katsuhiko Naoki, Hiroyuki Yasuda, Ryosuke Satomi, Sohei Nakayama, Satoshi Yoda, Shinnosuke Ikemura, Takashi Sato, Kota Ishioka, Daisuke Arai, Keiko Ohgino, Tetsuo Tani, Aoi Kuroda, Junko Hamamoto, Tomoko Betsuyaku. Activation of FGF2-FGFR1 pathway in EGFR-mutant lung cancer cell line with long-term gefitinib exposure. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5652. doi:10.1158/1538-7445.AM2013-5652

Activation of the FGF2-FGFR1 autocrine pathway: a novel mechanism of acquired resistance to gefitinib in NSCLC

Patients with non-small cell lung cancer (NSCLC) that harbors epidermal growth factor receptor (EGFR) mutations initially respond to EGFR-tyrosine kinase inhibitors (TKI) but eventually experience relapse. Acquired resistance to EGFR-TKIs is strongly associated with patient mortality. Thus, elucidation of the mechanism of acquired resistance to EGFR-TKIs is of great importance. In this study, gefitinib-resistant cell line models were established by long-term exposure to gefitinib using the gefitinib-sensitive lung cancer cell lines, PC9 and HCC827. Expression analyses indicated that both FGFR1 and FGF2 were increased in PC9 gefitinib-resistant (PC9 GR) cells as compared with PC9 naïve (PC9 na) cells. Importantly, proliferation of gefitinib-resistant cells was dependent on the FGF2 -FGFR1 pathway. Mechanistically, inhibition of either FGF2 or FGFR1 by siRNA or FGFR inhibitor (PD173074) restored gefitinib sensitivity in PC9 GR cells. These data suggest that FGF2 -FGFR1 activation through an autocrine loop is a novel mechanism of acquired resistance to EGFR-TKIs.

Relaxation of the topological T1 process in a two-dimensional foam

The so-called topological T1 process, during which bubbles within a foam exchange neighbours is studied. The Durand and Stone model (Phys. Rev. Lett., 97, 226101 (2006)) describes the growth of a film that is newly created during the T1 process, and also the evolution of surfactant concentration on this newly created film. Here some characteristic features of the Durand and Stone model (not previously described by Durand and Stone) are elucidated. In particular it is shown that the surfactant concentration on the newly created film is predicted to undergo an extremely rapid initial evolution, which occurs long before the film itself approaches anywhere near its final equilibrium length. Associated with this, the predicted length of the newly created film tends to exhibit an extremely rapid acceleration early on in its growth. An intermediate asymptotic analysis is developed to explain the above model predictions, by focussing on the regime when the film is several times larger than its initial length, but still several times smaller than its final length. A physical explanation is offered for these predictions in terms of slippage between material points instantaneously at the end of the newly created film, and the evolving location of the film endpoint itself: this slippage implies surfactant being transferred onto the newly created film from neighbouring films, overwhelming the amount of surfactant initially present. The implications of these predictions for the likely observations in an experimental study of the T1 process are discussed.

Bronchoscopic microsampling is a useful complementary diagnostic tool for detecting lung cancer

PURPOSE

Bronchoscopic microsampling (BMS) is a novel and direct method with which to obtain epithelial lining fluid (ELF) from the lungs. Analysis of DNA hypermethylation of tumor suppressor genes (TSGs) is expected to be a sensitive tool for the early detection of lung cancer. It has been reported that the existence of EGFR mutations and EML4-ALK gene rearrangements are related to the sensitivity of corresponding kinase inhibitors. We aimed to evaluate the suitability of ELF as a sample for analyzing molecular changes specific for lung cancer.

PATIENTS AND METHODS

We collected ELF from 61 lung cancer patients by BMS from the airway close to the peripheral lung nodule and purified the nucleic acids. We performed methylation specific PCR in each ELF as well as matched serum and tumor tissue for TSGs for DNA methylation analysis. We also examined EGFR mutations and EML4-ALK rearrangement.

RESULTS

The sensitivity for detecting DNA hypermethylation in ELF vs serum was 74.1% vs 18.5%. We found 60.1% of patients had at least one hypermethylation in ELF, while only 27.9% had it in serum. Of note, DNA hypermethylation was detected even in stage I patients (60.0%) and the detection rate was almost the same level in each stage. We also found the sensitivity for detecting EGFR mutation in ELF vs serum was 58.3% vs 8.3%. We detected an EML4-ALK fusion gene using ELF in one patient.

CONCLUSIONS

BMS is an alternative method to detect cancer specific genetic and epigenetic alterations and will be a useful complementary diagnostic tool for lung cancer.

SUMMARY

Investigation of genetic and epigenetic changes associated with lung cancer has clinical importance for its diagnosis and management. The clinical usefulness of bronchoscopic microsampling (BMS) in lung cancer has not yet been evaluated. This study demonstrates that BMS could be useful for detecting lung cancer specific molecular changes and valuable for early diagnosis and determination of treatment options for lung cancer.

Abstract 4956: Identification of microRNAs differentially expressed between lung squamous cell carcinoma and lung adenocarcinoma

Introduction: Recent advances in the treatment of non-small-cell lung cancer (NSCLC) with new agents require accurate histological subtyping at diagnosis in order to avoid the higher risk of an adverse response and obtain a maximum therapeutic response. However, interobserver variability, tumor heterogeneity and the degree of differentiation may influence the decision concerning a pathological diagnosis of NSCLC. We therefore in this study attempted to identify specific microRNAs as standardized biomarkers with high sensitivity and specificity for distinguishing between squamous cell carcinoma (SCC) and adenocarcinoma (AC).

Methods: Quantitative real time polymerase chain reaction (qRT-PCR) based microRNA array was performed to identify microRNAs differentially expressed between SCC and AC using 86 resected NSCLC samples as well as adjacent normal tissues. The results were confirmed by independent qRT-PCR assays with the same test samples and an additional 88 validation samples and the usefulness of the identified microRNAs as biomarkers to distinguish between SCC and AC was evaluated.

Results: Three microRNAs (hsa-miR-196b, hsa-miR-205 and hsa-miR-375) were identified. Discriminant analysis combining all 3 microRNAs appeared to distinguish SCC from AC accurately in the test samples and the validation samples, showing sensitivity and specificity of 76% and 80%, and 85% and 83%, respectively.

Conclusions: Hsa-miR-196b, hsa-miR-205 and hsa-miR-375 were identified as biomarkers capable of distinguishing between lung SCC and lung AC. These newly identified microRNAs may prove to be highly valuable molecular markers for the classification of NSCLC histologic subtypes, and could potentially contribute to the pathogenesis of each subtype of NSCLC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4956. doi:10.1158/1538-7445.AM2011-4956

Distinct epigenetic regulation of tumor suppressor genes in putative cancer stem cells of solid tumors

Epigenetic gene regulation plays essential roles in differentiation of embryonic and tissue stem cells. In these benign undifferentiated cells, some polycomb targeted genes are kept in a state of DNA hypomethylation and they have a distinct chromatin signature termed bivalent chromatin structure to maintain their plasticity. We hypothesized that cancer stem cells (CSC), the malignant counterpart of these cells, are also under the control of epigenetics like benign stem cells. We compared the DNA methylation and chromatin structure in 10 tumor suppressor genes between CSC and differentiated cancer cells of MCF7 and Huh7 cells. We found that the level of DNA methylation was indeed significantly lower in CSC, while surprisingly, the bivalent chromatin structure was more ubiquitously seen in differentiated cancer cells compared to CSC. However, repressive marks of chromatin structure, namely H3K27me3 and EZH2, were significantly lower in CSC. As a consequence, CSC remained in a higher transcriptionally active chromatin state compared to differentiated cancer cells. We found that the differentiation of CSCs is also epigenetically regulated. These findings could help towards a comprehensive understanding of CSC, and also improve the development of eradicative therapies against human malignancies.

A phase I study of S-1 and irinotecan combination therapy in previously treated advanced non-small cell lung cancer patients

BACKGROUND

This phase I study was conducted to evaluate the feasibility and to determine the recommended doses of the combination therapy of S-1 and irinotecan (CPT-11) in patients with advanced non-small cell lung cancer (NSCLC) as second-line treatment.

METHODS

Patients with NSCLC who were previously treated with one chemotherapy regimen and had a performance status of 0 or 1 were eligible. CPT-11 was administered at 60 mg/m² (level 1), 80 mg/m² (level 2) on days 1 and 8, and oral S-1 was administered at 80 mg/day for body surface area (BSA) less than 1.25 m², 100 mg/day for BSA 1.25-1.5 m², and 120 mg/day for BSA more than 1.5 m² on days 1-14 every 3 weeks. The dose-limiting toxicity (DLT) was defined as grade 4 leukocytopenia or neutropenia, grade ≥ 3 neutropenia with fever over 38°C, grade ≥ 3 thrombocytopenia, or grade ≥ 3 major nonhematological toxicities.

RESULTS

Nine patients were enrolled in the study. None of 3 patients enrolled in level 1 had any DLT. Of 6 patients in level 2, 2 patients had grade 3 diarrhea and one had grade 3 interstitial pneumonia. Level 1 was declared as the recommended dose.

CONCLUSION

The feasibility of the combination therapy of S-1 and CPT-11 was shown in the second-line setting for the treatment of advanced NSCLC. The recommended dose of CPT-11 was 60 mg/m² combined with standard dose of S-1 for phase II trials of pretreated advanced NSCLC patients.

[A case of fat embolism syndrome associated with pathological femoral fracture caused by metastatic adenocarcinoma of the lung]

A 76-year-old woman with multiple bone metastases from lung adenocarcinoma was admitted due to a pathological femoral fracture. On the night after admission, her consciousness deteriorated rapidly and she developed progressive respiratory failure. Computed tomography of the chest revealed diffuse ground glass opacities in both lungs, and magnetic resonance imaging of the brain showed multiple acute infarctions. Her condition improved after several days of supportive treatment with oxygen, corticosteroids and diuretics. Fat embolism syndrome should be considered as a differential diagnosis if consciousness disturbance and respiratory failure occur in patients with metastatic bone carcinoma and pathological long bone fractures.

Abstract 5302: Overcoming cancer immune evasion in lung carcinoma using EGFR-TKI (Gefitinib)

Clinical studies for immunotherapy targeting various types of carcinoma, including lung carcinoma, are currently underway, yet the clinical effectiveness of these therapies is very limited. Recent findings demonstrate that cancer immune evasion is a major contributing factor to this problem. Cancer cells produce a variety of immunosuppressive molecules that inhibit the host cell's immune response, leading to conditions such as cachexia that decrease patients’ quality of life. EGFR mutations in lung carcinoma are known to lead to processes characteristic of malignancies, such as cell cycle progression, metastasis, and angiogenesis. Based on these observations, we tested the hypothesis that EGFR activation leads to immune evasion by cancer cells via the production of various immunosuppressive molecules.

In this study, 6 lung adenocarcinoma cell lines were used, namely A549, RELF-LC-OK, PC-9, HCC-827, NCI-H1650, and NCI-H1975. We demonstrate that these cells secrete immunosuppressive cytokines such as IL-6, TGF-beta and VEGF, which inhibit the maturation of dendritic cells and prevent them to activate T cells. Then, we show that Gefitinib administration at sub-lethal concentration inhibits the production of immunosuppressive cytokines in EGFR-TKI sensitive PC-9 and HCC-827 cells those with EGFR mutations as well as in EGFR-TKI resistant NCI-H1650 cells that have an EGFR mutation but lack the PTEN gene. While, cytokine production is not inhibited by Gefitinib in A549 and RELF-LC-OK cells with wild type EGFR genes and NCI-H1975 cells that have both EGFR-TKI sensitive and resisitant mutations. Additionally, EGFR-TKI administration in PC-9, HCC827, and NCI-H1650 cells restores dendritic cell function, which was initially reduced by the supernatant of tumor cells.

These results show that lung adenocaricinoma harboring EGFR mutations evade immune response through secreteting immunosuppressive agents and that the immune response is restored by Gefitinib administration. Thus, the combination of Gefitinib and immunotherapy may have synergistic effect and will be a promising treatment of lung cancer patients harboring EGFR mutation, including certain population of EGFR-TKI resistant cases.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5302.