Real-world first-line afatinib for advanced EGFR mutation-positive non-small cell lung cancer in Korea: updated survival data.

Background: Data from clinical trials and real-world studies show that afatinib is effective in treating non-small cell lung cancer (NSCLC) harboring activating mutations in the epidermal growth factor receptor (EGFR) gene. A previous analysis of patients enrolled in the Korean Academy of Tuberculosis and Respiratory Disease (KATRD) EGFR cohort showed that first-line afatinib was well tolerated and effectiveness results were encouraging. At the time of the previous analysis, survival data were not mature. Here we briefly present updated survival data from the cohort. Methods: The study was a retrospective, multicenter (15 sites) review of electronic records of Korean adult patients (aged >20 years) with advanced EGFR mutation-positive NSCLC who initiated first-line afatinib (N=421). Progression-free survival (PFS) and overall survival (OS) were evaluated using Kaplan-Meier survival curves. Results: Overall, median PFS was 20.2 months and median OS was 48.6 months. OS rates at 36 and 60 months were 60.1% and 42.3%, respectively. Presence vs. absence of baseline brain metastases was associated with significantly reduced median PFS (14.9 vs. 28.0 months; P<0.001) and median OS (32.2 vs. 65.6 months; P<0.001). The presence of common baseline EGFR mutations (Del19, L858R) was associated with significantly prolonged median OS (49.6 vs. 30.1 months; P=0.017). In patients stratified by the presence/absence of T790M EGFR mutation, the T790M mutation was associated with significantly reduced median PFS (P=0.0005) but there was no significant difference between groups in survival (P=0.263). There were no significant differences in PFS or OS for patients stratified by afatinib dose reduction or by age group (<70 vs. ≥70 years). Conclusions: Afatinib was effective in Korean patients with EGFR mutation-positive NSCLC with median OS over 4 years. The presence of baseline brain metastases and/or uncommon EGFR mutations were associated with reduced survival. In the absence of baseline brain metastases, median OS was more than 5 years.

Healthcare utilization of lung cancer patients associated with exposure to fine particulate matter: A Korean cohort study.

BACKGROUND: Higher concentrations of particulate matter (PM) have been shown to cause deterioration of the symptoms of respiratory and cardiovascular disease in several regional studies. Here, we aimed to investigate the healthcare utilization of lung cancer patients associated with short-term exposure to PM at the national level in Korea. METHODS: We extracted the data of 210 558 subjects over a period of 3 years (2015-2017), who were diagnosed with lung cancer before 2015 and benefited from the National Health Insurance Sharing Service. We performed the interpolation method using the geographic information system to calculate the estimated mean PM2.5 and PM10 concentrations by regions and classified three groups as high (upper 10%), intermediate (10%-90%), and low (bottom 10%) based on the mean PM mass concentrations of the month. RESULTS: The monthly average number of outpatient visits was significantly increased in high PM2.5 urban areas (46.296 vs. 50.646, p = 0.015). In high PM2.5 nationwide regions, the monthly average number of emergency admission was significantly increased (0.528 vs. 0.785, p = 0.001). The outpatient visits tended to change with PM2.5 concentration and correlated with PM10 /PM2.5 concentrations in urban and nationwide areas. In high PM2.5 urban regions, there was a significant increase in bronchodilator prescriptions (3.102 vs. 3.758, p = 0.008). Concerning high PM2.5 nationwide regions, there were significantly increased prescriptions of antibiotics, steroids, bronchodilators, antihistamines, and mucolytics. CONCLUSIONS: This study suggests that exposure to PM2.5 is significantly associated with hospital utilization and drug prescription in lung cancer patients.

Real-world analysis of first-line afatinib in patients with EGFR-mutant non-small cell lung cancer and brain metastasis: survival and prognostic factors.

Background: Overall survival (OS) in patients with non-small cell lung cancer (NSCLC) and brain metastases (BMs) is poor. We aimed to identify prognostic factors and ascertain treatment outcomes of first-line afatinib for patients with epidermal growth factor receptor (EGFR)-mutant NSCLC with BM in a real-world setting. Methods: This retrospective observational study reviewed electronic records of patients with EGFR-mutant NSCLC who received first-line afatinib treatment between October 2014 and October 2019 in 16 hospitals across South Korea. The Kaplan-Meier method estimated time on treatment (TOT) and OS; multivariate analyses were performed using Cox proportional hazards (PH) models. Results: Among 703 patients who received first-line afatinib, 262 (37.3%) had baseline BM. Of 441 patients without baseline BM, 92 (20.9%) developed central nervous system (CNS) failure. Compared with patients without CNS failure, those with CNS failure during afatinib treatment were younger (P=0.012), had a higher Eastern Cooperative Oncology Group (ECOG) performance status (PS) (P<0.001), increased metastatic site involvement (P<0.001), advanced stage disease (P<0.001), with liver metastasis (P=0.008) and/or bone metastasis (P<0.001) at baseline. Cumulative incidence of CNS failure in years 1, 2 and 3 was 10.1%, 21.5% and 30.0%, respectively. In multivariate analysis, cumulative incidence was significantly higher in patients with ECOG PS ≥2 (P<0.001), uncommon EGFR mutations (P=0.001), and no baseline pleural metastasis (P=0.017). Median TOT was 16.0 months (95% CI: 14.8-17.2) and, in patients with CNS failure, without CNS failure, and with baseline BM was 12.2, 18.9, and 14.1 months, respectively (P<0.001). Median OS was 52.9 months (95% CI: 45.4-60.3) and, in patients with CNS failure, without CNS failure, and with baseline BM was 29.1, 67.3 and 48.5 months, respectively (P<0.001). Conclusions: First-line afatinib in the real-world setting showed clinically meaningful effectiveness in patients with EGFR-mutant NSCLC and BM. CNS failure was a poor prognostic factor for TOT and OS correlating with younger age, poor ECOG PS, higher metastatic number, advanced disease stage, uncommon EGFR mutations, and baseline liver and/or bone metastases.

Role of ABCA2 and its single nucleotide polymorphisms (4873T>A and 4879G>C) in the regulation of multi-drug resistance in oral squamous carcinoma cells.

Lysosomal exocytosis is an essential cellular event for remodeling the extracellular matrix through secreting lysosomal enzymes and developing drug resistance. However, the detailed mechanism underlying the lysosomal exocytosis-driven acquisition of drug resistance is not completely understood. Genetic variations in gefitinib-sensitive (HSC3) and -resistant (HSC3/GR) oral squamous carcinoma cell lines were identified using whole-exome sequencing (WES). The physiological role of the ATP-binding cassette subfamily A member 2 (ABCA2) in gefitinib-induced lysosomal trafficking was evaluated in vitro, through overexpressing ABCA2 and its single nucleotide polymorphisms (SNPs). WES analysis showed that the 554 SNPs harboring 244 genes appeared to be differentially generated depending on gefitinib resistance. Among these genes, ABCA2 was enriched in 24 of 39 gene ontology terms. Two missense SNPs of ABCA2, 4873T  >  A (rs1831123356) and 4873T  >  A, were generated only in gefitinib-sensitive cells. Furthermore, HEK293 cells expressing the wild-type ABCA2 (WT ABCA2) acquired tolerance for gefitinib-induced cytotoxicity by increasing gefitinib sequestration in lysosomes and lysosomal exocytosis. Conversely, cells expressing each ABCA2 SNP exhibited lower efficacy in developing tolerance to gefitinib-induced responses than those expressing WT ABCA2. Notably, HSC3/GR cells were also tolerant to erlotinib and sunitinib but not osimertinib. Furthermore, tolerance for multiple tyrosine kinase inhibitors was attenuated by the deletion of ABCA2. These findings demonstrate that ABCA2 and its SNPs should be considered prominent targets for overcoming multi-drug resistance and enhancing the efficacy of chemotherapeutics.

Final Report on Real-World Effectiveness of Sequential Afatinib and Osimertinib in EGFR-Positive Advanced Non-Small Cell Lung Cancer: Updated Analysis of the RESET Study.

PURPOSE: This study aimed to report the final analysis of time-on-treatment (TOT) and overall survival (OS) in patients with advanced-stage epidermal growth factor receptor (EGFR)+ non-small cell lung cancer (NSCLC) who received sequential afatinib and osimertinib and to compare the outcomes with other second-line regimens (comparator group). MATERIALS AND METHODS: In this updated report, the existing medical records were reviewed and rechecked. TOT and OS were updated and analyzed according to clinical features using the Kaplan-Meier method and log-rank test. TOT and OS were compared with those of the comparator group, in which most patients received pemetrexed-based treatments. A multivariable Cox proportional hazard model was used to evaluate features that could affect survival outcomes. RESULTS: The median observation time was 31.0 months. The follow-up period was extended to 20 months. A total of 401 patients who received first-line afatinib were analyzed (166 with T790M+ and second-line osimertinib, and 235 with unproven T790M and other second-line agents). Median TOTs on afatinib and osimertinib were 15.0 months (95% confidence interval [CI], 14.0 to 16.1) and 11.9 months (95% CI, 8.9 to 14.6), respectively. The median OS in the osimertinib group was 54.3 months (95% CI, 46.7 to 61.9), much longer than that in the comparator group. In patients who received osimertinib, the OS was longest with Del19+ (median, 59.1; 95% CI, 48.7 to 69.5). CONCLUSION: This is one of the largest real-world studies reporting the encouraging activity of sequential afatinib and osimertinib in Asian patients with EGFR+ NSCLC who acquired the T790M mutation, particularly Del19+.

Real-World Study of Osimertinib in Korean Patients with Epidermal Growth Factor Receptor T790M Mutation-Positive Non-Small Cell Lung Cancer.

PURPOSE: Although osimertinib is the standard-of-care treatment of epidermal growth factor receptor (EGFR) T790M mutation-positive non-small cell lung cancer, real-world evidence on the efficacy of osimertinib is not enough to reflect the complexity of the entire course of treatment. Herein, we report on the use of osimertinib in patients with EGFR T790M mutation-positive non-small cell lung cancer who had previously received EGFR tyrosine kinase inhibitor (TKI) treatment in Korea. MATERIALS AND METHODS: Patients with confirmed EGFR T790M after disease progression of prior EGFR-TKI were enrolled and administered osimertinib 80 mg daily. The primary effectiveness outcome was progression-free survival, with time-to-treatment discontinuation, treatment and adverse effects leading to treatment discontinuation, and overall survival being the secondary endpoints. RESULTS: A total of 558 individuals were enrolled, and 55.2% had investigator-assessed responses. The median progression-free survival was 14.2 months (95% confidence interval [CI], 13.0 to 16.4), and the median time-to-treatment discontinuation was 15.0 months (95% CI, 14.1 to 15.9). The median overall survival was 36.7 months (95% CI, 30.9 to not reached). The benefit with osimertinib was consistent regardless of the age, sex, smoking history, and primary EGFR mutation subtype. However, hepatic metastases at the time of diagnosis, the presence of plasma EGFR T790M, and the shorter duration of prior EGFR-TKI treatment were poor predictors of osimertinib treatment. Ten patients (1.8%), including three with pneumonitis, had to discontinue osimertinib due to severe adverse effects. CONCLUSION: Osimertinib demonstrated its clinical effectiveness and survival benefit for EGFR T790M mutation-positive in Korean patients with no new safety signals.

TRPML3 enhances drug resistance in non-small cell lung cancer cells by promoting Ca2+-mediated lysosomal trafficking.

Lysosomes are emerging as versatile signaling hubs that mediate numerous cellular processes, including the development of drug resistance in cancer cells. Transient receptor potential mucolipin 3 (TRPML3), an endolysosomal Ca2+-permeable channel, is implicated in regulating lysosomal trafficking during endocytosis and autophagy. However, the role of TRPML3 in cancer progression remains unclear. In this study, we focused on identifying key molecules that modulate exosomal release triggered by lysosomal exocytosis during the development of gefitinib resistance in non-small cell lung cancer (NSCLC). We found that the basal release of exosomes and lysosomal exocytosis is higher in the gefitinib-resistant NSCLC cell line HCC827/GR than in the gefitinib-sensitive NSCLC cell line HCC827. Notably, exosomal release and lysosomal exocytosis were associated with an increase in TRPML3 expression. Lysosomal Ca2+ release via TRPML3 was triggered by the gefitinib-mediated elevation of lysosomal pH. Furthermore, TRPML3 deficiency enhanced the gefitinib-mediated increase in sub-G0 cell population, reduction of cell proliferation, and poly (ADP-ribose) polymerase cleavage. These data demonstrated that TRPML3 is a promising modulator of drug resistance. By sensing the elevation of lysosomal pH, it mediates lysosomal Ca2+ release, lysosomal trafficking and exocytosis, and exosomal release. Taken together, our study is the first to report the autonomous defense mechanism developed in NSCLC cells against the small-molecule tyrosine kinase inhibitor gefitinib, leading to acquired drug resistance.

First-line Afatinib in Patients With Non-small-cell Lung Cancer With Uncommon EGFR Mutations in South Korea.

BACKGROUND/AIM: Non-small cell lung cancers (NSCLCs) harboring uncommon epidermal growth factor receptor (EGFR) mutations are heterogeneous and show variable prevalence and clinical responses to EGFR tyrosine kinase inhibitors. We investigated the characteristics of uncommon EGFR mutations and the clinical efficacy of afatinib in patients with NSCLC harboring uncommon EGFR mutations. PATIENTS AND METHODS: In this multicenter, retrospective study, we analyzed patients with NSCLC with uncommon EGFR mutations in 16 South Korean institutes. Mutations were categorized according to their incidence: 1) major uncommon mutations (G719X and L861Q), 2) compound mutations, and 3) minor uncommon mutations (exon 20 insertion, S768I, and de novo T790M). RESULTS: Of 703 patients with EGFR-mutant NSCLC, 64 (9.1%) had uncommon EGFR mutations. Afatinib demonstrated activity against tumors harboring major uncommon mutations [median time of treatment (TOT): 20.3 months, 95% confidence interval (CI)=15.1-25.5; overall survival (OS): 30.6 months, 95% CI=26.3-34.8] and compound mutations (median TOT: 12.3 months, 95% CI=7.7-17.0; OS: 29.1 months, 95% CI=20.4-37.7) but not against tumors harboring minor uncommon mutations (median TOT: 3.8 months, 95% CI=1.7-6.0; OS: 8.5 months, 95% CI=5.2-11.7). The S768I mutation was present in 14 patients (1.99%). The median TOT and OS were not significantly different between S768I mutations and resistant exon 20 mutations. CONCLUSION: Afatinib is effective in patients with NSCLC harboring major uncommon and compound EGFR mutations.

miR-4487 Enhances Gefitinib-Mediated Ubiquitination and Autophagic Degradation of EGFR in Non-Small Cell Lung Cancer Cells by Targeting USP37.

PURPOSE: With the identification of epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) cells, EGFR-tyrosine kinase inhibitors (TKIs) are being used widely as the first-line of treatment in NSCLC. These inhibitors block auto-phosphorylation of activated EGFR by competing with ATP binding and mediate EGFR degradation independent of exogenous epidermal growth factor, which is associated with the mutation variants of EGFR. However, the precise mechanisms underlying the TKI-mediated EGFR degradation are still unclear. MATERIALS AND METHODS: To examine the physiological roles of miR-4487 and ubiquitin-specific peptidase 37 (USP37) in gefitinib-mediated EGFR degradation in NSCLC cells, multiple NSCLC cell lines were applied. The level of EGFR expression, apoptosis marker and autophagic flux were determined by western blot. Expression level of miR-4487 and cell cycle arrest was analyzed by TaqMan assay and flow cytometry respectively. RESULTS: We found that gefitinib mediates EGFR degradation under normal culture conditions, and is dependent on autophagic flux and the mutation variants of EGFR. Gefitinib reduced expression levels of USP37, which mediated EGFR degradation similar to gefitinib. Our results also showed a gefitinib-mediated increase in endogenous miR-4487 level and presented evidence for the direct targeting of USP37 by miR-4487, resulting in the sequential enhancement of ubiquitination, autophagy, and EGFR degradation. Thus, the depletion of USP37 and overexpression of miR-4487 led to an increase in gefitinib-mediated apoptotic cell death. CONCLUSION: These data suggest that miR-4487 is a potential target for treating NSCLC, and miR-4487/USP37-regulated EGFR degradation is a determinant for developing gefitinib resistance.

Afatinib Mediates Autophagic Degradation of ORAI1, STIM1, and SERCA2, Which Inhibits Proliferation of Non-Small Cell Lung Cancer Cells.

BACKGROUND: The expression of calcium signaling pathway molecules is altered in various carcinomas, which are related to the proliferation and altered characteristics of cancer cells. However, changes in calcium signaling in anti-cancer drugresistant cells (bearing a T790M mutation in epidermal growth factor receptor [EGFR]) remain unclear. METHODS: Afatinib-mediated changes in the level of store-operated Ca2+ entry (SOCE)-related proteins and intracellular Ca2+ level in non-small cell lung cancer cells with T790M mutation in the EGFR gene were analyzed using western blot and ratiometric assays, respectively. Afatinib-mediated autophagic flux was evaluated by measuring the cleavage of LC3B-II. Flow cytometry and cell proliferation assays were conducted to assess cell apoptosis and proliferation. RESULTS: The levels of SOCE-mediating proteins (ORAI calcium release-activated calcium modulator 1 [ORAI1], stromal interaction molecule 1 [STIM1], and sarco/endoplasmic reticulum Ca2+ ATPase [SERCA2]) decreased after afatinib treatment in non-small cell lung cancer cells, whereas the levels of SOCE-related proteins did not change in gefitinibresistant non-small cell lung cancer cells (PC-9/GR; bearing a T790M mutation in EGFR ). Notably, the expression level of SOCE-related proteins in PC-9/GR cells was reduced also responding to afatinib in the absence of extracellular Ca2+. Moreover, extracellular Ca2+ influx through the SOCE was significantly reduced in PC-9 cells pre-treated with afatinib than in the control group. Additionally, afatinib was found to decrease the level of SOCE-related proteins through autophagic degradation, and the proliferation of PC-9GR cells was significantly inhibited by a lack of extracellular Ca2+. CONCLUSION: Extracellular Ca2+ plays important role in afatinib-mediated autophagic degradation of SOCE-related proteins in cells with T790M mutation in the EGFR gene and extracellular Ca2+ is essential for determining anti-cancer drug efficacy.

Sequential treatment of afatinib and osimertinib or other regimens in patients with advanced non-small-cell lung cancer harboring EGFR mutations: Results from a real-world study in South Korea.

OBJECTIVES: The optimal sequence for the administration of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) for treating non-small cell lung cancer (NSCLC) is still unclear. This study aimed to evaluate the efficacy of sequential afatinib and osimertinib treatment in patients with NSCLC harboring EGFR mutations. MATERIALS AND METHODS: Electronic records of patients with EGFR-mutated NSCLC, who were administered afatinib and osimertinib (group A) or other chemotherapy (group B) between October 2014 and 2019, across 16 hospitals in South Korea were reviewed. The primary outcome, time on treatment (TOT), secondary outcome, and overall survival (OS) were estimated using the Kaplan-Meier method and log-rank test. Multivariate analyses were performed using the Cox proportional hazards model. RESULTS: Of the 737 patients who received frontline afatinib treatment, 324 with complete records were selected (group A: 126, group B: 198). All patients in group A were T790M positive after afatinib, while patients in group B were all negative or unknown. The median TOT was 35.4 months (95% confidence interval [CI]: 27.7-45.6) in group A and 20.8 months (95% CI: 19.4-24.0) in group B. The median TOT with afatinib was 13.0 months (95% CI: 12.0-13.9) overall and 15.7 months (95% CI: 13.9-17.3) in group A. The 2- and 3-year survival rates were 86.0 and 69.3% in group A and 75.9 and 55.3% in group B, respectively. CONCLUSION: Sequential afatinib and osimertinib treatment resulted in better survival rates than treatment with afatinib followed by other chemotherapies.

Real-world experience of afatinib as first-line therapy for advanced EGFR mutation-positive non-small cell lung cancer in Korea.

BACKGROUND: We investigated the clinical characteristics and treatment outcomes of Korean patients receiving first-line afatinib for advanced epidermal growth factor receptor mutation-positive (EGFRm+) non-small cell lung cancer (NSCLC) in a real-world setting. METHODS: Electronic case reports were retrospectively reviewed from patients across 15 sites in South Korea. Outcome measures included baseline characteristics, overall response rate (ORR), time-to-treatment discontinuation (TTD), and overall survival (OS). Subgroups were: presence/absence of brain metastases at baseline, dose reductions, and baseline EGFR mutation category. RESULTS: Among 422 patients, 39.8% had brain metastases and 59.0%/25.1%/10.0%/5.0% had Del19/L858R/compound/uncommon EGFR mutations at baseline. ORR was 62.6% overall; responses were observed across all EGFR mutation categories, including against compound mutations. Median TTD was 17.8 months; median OS was not reached (NR). Median TTD and OS were longer in patients without versus with brain metastases (TTD: 22.9 vs. 14.8 months, P=0.001; OS: NR vs. 40.3 months, P=0.0009) and patients with versus without dose reductions (TTD: 22.2 vs. 14.2 months, P=0.0004; OS: NR vs. 40.3 months, P=0.0117). Median OS was 30.5/37.7 months in patients receiving chemotherapy/osimertinib as subsequent therapy. The most common treatment-related adverse events (TRAEs; any grade/grade ≥3) were diarrhea (31.3%/8.5%) and rash (23.0%/8.1%). Overall, 34 patients (8.1%) discontinued afatinib due to AEs. CONCLUSIONS: Afatinib was well tolerated with no new safety signals, and efficacy was encouraging in Korean patients with EGFRm+ NSCLC, including those with baseline brain metastases and/or uncommon EGFR mutations. AE management with dose reductions facilitated a long TTD, prolonging the chemotherapy-free period for many patients.

Longitudinal Changes in Clinical Features, Management, and Outcomes of Idiopathic Pulmonary Fibrosis. A Nationwide Cohort Study.

Rationale: In recent decades, diagnosis and treatment recommendations for idiopathic pulmonary fibrosis (IPF) have changed. In Korea, the average life expectancy has increased, unmet healthcare needs have been reduced, and the number of computed tomographic examinations performed has nearly doubled. The Korean Interstitial Lung Disease Study Group conducted a nationwide cohort study for idiopathic interstitial pneumonia, including IPF, and established a registry for IPF.Objectives: Using study data collected by the study group, this study aimed to evaluate longitudinal changes in clinical features, diagnosis, treatment, and mortality and analyze the extent to which changes in medication usage affected IPF-associated mortality.Methods: The study population included newly diagnosed patients with IPF from a cohort study (January 2002 to September 2008, n = 1,839, 2008 group) and prospective registry (January 2012 to August 2018, n = 1,345, 2018 group). Survival curves were estimated using the Kaplan-Meier method, and Cox regression models were used to identify mortality-associated risk factors in each group.Results: The 2018 group was younger, had fewer symptoms, had less honeycombing, underwent more serologic autoimmune marker and pulmonary function tests, had higher oxygen partial pressure and lower carbon dioxide partial pressure values, was less frequently diagnosed by surgical biopsy, and had better survival than the 2008 group. Steroid use and conservative care declined, whereas N-acetylcysteine use increased in this group. Antifibrotic agents were used in only the 2018 group. In the 2008 group, N-acetylcysteine was associated with lower mortality, whereas conservative care was associated with higher mortality. In the 2018 group, the use of antifibrotic agents was associated with lower mortality, and steroid use was associated with higher mortality. The survival rates in the 2008 and 2018 non-antifibrotic agent subgroups were similar.Conclusions: This study analyzed national IPF cohort data spanning 17 years. In clinical practice, the IPF diagnosis was made earlier, steroid and immunosuppressive agent use was reduced, and antifibrotic agents were administered. The survival of patients with IPF has improved over the decades, and antifibrotic use was consistently associated with improved survival.Clinical trial registered with clinicaltrials.gov (NCT04160715).

Restricting extracellular Ca2+ on gefitinib-resistant non-small cell lung cancer cells reverses altered epidermal growth factor-mediated Ca2+ response, which consequently enhances gefitinib sensitivity.

Non-small cell lung cancer (NSCLC), one of the leading causes of cancer-related death, has a low 5-year survival rate owing to the inevitable acquired resistance toward antitumor drugs, platinum-based chemotherapy, and targeted therapy. Epidermal growth factor (EGF)-EGF receptor (EGFR) signaling activates downstream events leading to phospholipase C/inositol trisphosphate (IP3)/Ca2+ release from IP3-sensitive Ca2+ stores to modulate cell proliferation, motility, and invasion. However, the role of EGFR-mediated Ca2+ signaling in acquired drug resistance is not fully understood. Here, we analyzed alterations of intracellular Ca2+ ([Ca2+]i) responses between gefitinib-sensitive NSCLC PC-9 cells and gefitinib-resistant NSCLC PC-9/GR cells, and we found that acute EGF treatment elicited intracellular Ca2+ ([Ca2+]i) oscillations in PC-9 cells but not in PC-9/GR cells. PC-9/GR cells presented a more sustained basal [Ca2+]i level, lower endoplasmic reticulum Ca2+ level, and higher spontaneous extracellular Ca2+ ([Ca2+]e) influx than PC-9 cells. Notably, restricting [Ca2+]e in both cell types induced identical [Ca2+]i oscillations, dependent on phospholipase C and EGFR activation. Consequently, restricting [Ca2+]e in PC-9/GR cells upregulated gefitinib-mediated poly (ADP-ribose) polymerase cleavage, an increase in Bax/Bcl-2 ratio, cytotoxicity, and apoptosis. In addition, nuclear factor of activated T cell (NFAT1) induction in response to EGF was inhibited by gefitinib in PC-9 cells, whereas EGF-mediated NFAT1 induction in PC-9/GR cells was sustained regardless of gefitinib treatment. Restricting [Ca2+]e in PC-9/GR cells significantly reduced EGF-mediated NFAT1 induction. These findings indicate that spontaneous [Ca2+]e influx in NSCLC cells plays a pivotal role in developing acquired drug resistance and suggest that restricting [Ca2+]e may be a potential strategy for modulating drug-sensitivity.

Korean Guidelines for Diagnosis and Management of Interstitial Lung Diseases: Part 1. Introduction.

Idiopathic interstitial pneumonia (IIP) is a histologically identifiable pulmonary disease without a known cause that usually infiltrates the lung interstitium. IIP is largely classified into idiopathic pulmonary fibrosis, idiopathic non-specific interstitial pneumonia, respiratory bronchiolitis-interstitial lung disease (ILD), cryptogenic organizing pneumonia, desquamative interstitial pneumonia, and acute interstitial pneumonia. Each of these diseases has a different prognosis and requires specific treatment, and a multidisciplinary approach that combines chest high-resolution computed tomography (HRCT), histological findings, and clinical findings is necessary for their diagnosis. Diagnosis of IIP is made based on clinical presentation, chest HRCT findings, results of pulmonary function tests, and histological findings. For histological diagnosis, video-assisted thoracoscopic biopsy and transbronchial lung biopsy are used. In order to identify ILD associated with connective tissue disease, autoimmune antibody tests may also be necessary. Many biomarkers associated with disease prognosis have been recently discovered, and future research on their clinical significance is necessary. The diagnosis of ILD is difficult because patterns of ILD are both complicated and variable. Therefore, as with other diseases, accurate history taking and meticulous physical examination are crucial.

Augmentation of NAD+ levels by enzymatic action of NAD(P)H quinone oxidoreductase 1 attenuates adriamycin-induced cardiac dysfunction in mice.

BACKGROUND: Adriamycin (ADR) is a powerful chemotherapeutic agent extensively used to treat various human neoplasms. However, its clinical utility is hampered due to severe adverse side effects i.e. cardiotoxicity and heart failure. ADR-induced cardiomyopathy (AIC) has been reported to be caused by myocardial damage and dysfunction through oxidative stress, DNA damage, and inflammatory responses. Nonetheless, the remedies for AIC are even not established. Therefore, we illustrate the role of NAD+/NADH modulation by NAD(P)H quinone oxidoreductase 1 (NQO1) enzymatic action on AIC. METHODS AND RESULTS: AIC was established by intraperitoneal injection of ADR in C57BL/6 wild-type (WT) and NQO1 knockout (NQO1-/-) mice. All Mice were orally administered dunnione (named NQO1 substrate) before and after exposure to ADR. Cardiac biomarker levels in the plasma, cardiac dysfunction, oxidative biomarkers, and mRNA and protein levels of pro-inflammatory mediators were determined compared the cardiac toxicity of each experimental group. All biomarkers of Cardiac damage and oxidative stress, and mRNA levels of pro-inflammatory cytokines including cardiac dysfunction were increased in ADR-treated both WT and NQO1-/- mice. However, this increase was significantly reduced by dunnione in WT, but not in NQO1-/- mice. In addition, a decrease in SIRT1 activity due to a reduction in the NAD+/NADH ratio by PARP-1 hyperactivation was associated with AIC through increased nuclear factor (NF)-κB p65 and p53 acetylation in both WT and NQO1-/- mice. While an elevation in NAD+/NADH ratio via NQO1 enzymatic action using dunnione recovered SIRT1 activity and subsequently deacetylated NF-κB p65 and p53, however not in NQO1-/- mice, thereby attenuating AIC. CONCLUSION: Thus, modulation of NAD+/NADH by NQO1 may be a novel therapeutic approach to prevent chemotherapy-associated heart failure, including AIC.

A national survey of lung cancer specialists' views on low-dose CT screening for lung cancer in Korea.

Lung cancer specialists play an important role in designing and implementing lung cancer screening. We aimed to describe their 1) attitudes toward low-dose lung computed tomography (LDCT) screening, 2) current practices and experiences of LDCT screening and 3) attitudes and opinions towards national lung cancer screening program (NLCSP). We conducted a national web-based survey of pulmonologists, thoracic surgeons, medical oncologists, and radiological oncologists who are members of Korean Association for Lung Cancer (N = 183). Almost all respondents agreed that LDCT screening increases early detection (100%), improves survival (95.1%), and gives a good smoking cessation counseling opportunity (88.6%). Most were concerned about its high false positive results (79.8%) and the subsequent negative effects. Less than half were concerned about radiation hazard (37.2%). Overall, most (89.1%) believed that the benefits outweigh the risks and harms. Most (79.2%) stated that they proactively recommend LDCT screening to those who are eligible for the current guidelines, but the screening propensity varied considerably. The majority (77.6%) agreed with the idea of NLCSP and its beneficial effect, but had concerns about the quality control of CT devices (74.9%), quality assurance of radiologic interpretation (63.3%), poor access to LDCT (56.3%), and difficulties in selecting eligible population using self-report history (66.7%). Most (79.2%) thought that program need to be funded by a specialized fund rather than by the National Health Insurance. The opinions on the level of copayment for screening varied. Our findings would be an important source for health policy decision when considering for NLCSP in Korea.

Effects of Banxia Xiexin Decoction () on Cisplatin-Induced Apoptosis of Human A549 Lung Cancer Cells.

OBJECTIVE: To examinie the synergistic effects of Banxia Xiexin Decoction (, Known as Banhasasim-tang in Korean) extract (BXDE) on cisplatin-induced cytotoxicity in the A549 human lung cancer cell lines. METHODS: A549 cells were treated with varying concentrations (50-200 µg/mL) of cisplatin and BXDE alone or in combination for 96 h. We used 1-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan assay and flow cytometry to analyze cell viability and apoptosis, respectively. RESULTS: The exposure of cells to cisplatin and BXDE alone or in combination decreased cell viability dose- and time-dependently (P<0.05), which was found to be mediated by the apoptotic pathway as confirmed by the increase in the annexin V+/propidium iodide- stained cell population and a ladder pattern of discontinuous DNA fragments. Furthermore, the apoptosis was inhibited by the pan-caspase inhibitor, benzyloxycarbonyl-Val-Ala-Asp (OMe) fluoromethylketone (z-VAD-FMK). CONCLUSIONS: BXDE significantly potentiated apoptotic effects of cisplatin in A549 cells. Moreover, apoptosis induced by BXDE might be the pivotal mechanism mediating its chemopreventative action against cancer.

NAD+ augmentation ameliorates acute pancreatitis through regulation of inflammasome signalling.

Acute pancreatitis (AP) is a complicated disease without specific drug therapy. The cofactor nicotinamide adenine dinucleotide (NAD+) is an important regulator of cellular metabolism and homeostasis. However, it remains unclear whether modulation of NAD+ levels has an impact on caerulein-induced AP. Therefore, in this study, we investigated the effect of increased cellular NAD+ levels on caerulein-induced AP. We demonstrated for the first time that the activities and expression of SIRT1 were suppressed by reduction of intracellular NAD+ levels and the p53-microRNA-34a pathway in caerulein-induced AP. Moreover, we confirmed that the increase of cellular NAD+ by NQO1 enzymatic action using the substrate ß-Lapachone suppressed caerulein-induced AP with down-regulating TLR4-mediated inflammasome signalling, and thereby reducing the inflammatory responses and pancreatic cell death. These results suggest that pharmacological stimulation of NQO1 could be a promising therapeutic strategy to protect against pathological tissue damage in AP.

Lung cancer specialist physicians' attitudes towards e-cigarettes: A nationwide survey.

OBJECTIVES: Despite a sharp increase in e-cigarette use, there is debate about whether e-cigarettes are a viable alternative for harm reduction, and the forms that regulation should take. Healthcare providers can be effective in offering guidance to patients and their families and shaping regulatory policy. We described lung cancer specialists' attitudes toward e-cigarettes and its regulation. METHODS: We undertook a nationwide survey of pulmonologists, thoracic surgeons, medical and radiological oncologists who are members of Korean Association for Lung Cancer. Survey items included beliefs and attitudes toward e-cigarettes, attitudes toward e-cigarette regulation and preparedness on discussing e-cigarettes with their patients. RESULTS: Most respondents believed that e-cigarettes are not safer than conventional tobacco cigarettes (75.7%) or smokeless tobacco (83.2%), and feared that discussing e-cigarettes with the patients would encourage use (65.4%). They did not consider it a smoking cessation treatment (78.3%), and thus would not recommend it to smokers who do not want to quit (82.2%) or who failed to quit with conventional smoking cessation treatment (74.1%). Most respondents supported all examples of e-cigarette regulations, including the safety and quality check (97.8%), warning label (97.8%), advertisement ban (95.1%), restriction of flavoring (78.4%), minimum purchasing age (99.5%), and restriction of indoor use (94.6%). Most learned about e-cigarettes from media and advertisements, or conversation with patients rather than through professional scientific resources, and reported discomfort when discussing e-cigarette with patients. CONCLUSION: Lung cancer specialist physicians in Korea doubt the safety of e-cigarette and use of e-cigarette as smoking cessation treatment, and supported strict regulation. However, only 20% reported that they obtained information on e-cigarettes from the scientific literature and many lacked adequate knowledge based on scientific evidence, suggesting the need for better preparedness. Nevertheless, the views of professionals revealed from our study could help to develop clinical guidelines and regulatory guidance.