Osimertinib in Resected EGFR-Mutated Non-Small-Cell Lung Cancer.

BACKGROUND: Osimertinib is standard-of-care therapy for previously untreated epidermal growth factor receptor (EGFR) mutation-positive advanced non-small-cell lung cancer (NSCLC). The efficacy and safety of osimertinib as adjuvant therapy are unknown. METHODS: In this double-blind, phase 3 trial, we randomly assigned patients with completely resected EGFR mutation-positive NSCLC in a 1:1 ratio to receive either osimertinib (80 mg once daily) or placebo for 3 years. The primary end point was disease-free survival among patients with stage II to IIIA disease (according to investigator assessment). The secondary end points included disease-free survival in the overall population of patients with stage IB to IIIA disease, overall survival, and safety. RESULTS: A total of 682 patients underwent randomization (339 to the osimertinib group and 343 to the placebo group). At 24 months, 90% of the patients with stage II to IIIA disease in the osimertinib group (95% confidence interval [CI], 84 to 93) and 44% of those in the placebo group (95% CI, 37 to 51) were alive and disease-free (overall hazard ratio for disease recurrence or death, 0.17; 99.06% CI, 0.11 to 0.26; P<0.001). In the overall population, 89% of the patients in the osimertinib group (95% CI, 85 to 92) and 52% of those in the placebo group (95% CI, 46 to 58) were alive and disease-free at 24 months (overall hazard ratio for disease recurrence or death, 0.20; 99.12% CI, 0.14 to 0.30; P<0.001). At 24 months, 98% of the patients in the osimertinib group (95% CI, 95 to 99) and 85% of those in the placebo group (95% CI, 80 to 89) were alive and did not have central nervous system disease (overall hazard ratio for disease recurrence or death, 0.18; 95% CI, 0.10 to 0.33). Overall survival data were immature; 29 patients died (9 in the osimertinib group and 20 in the placebo group). No new safety concerns were noted. CONCLUSIONS: In patients with stage IB to IIIA EGFR mutation-positive NSCLC, disease-free survival was significantly longer among those who received osimertinib than among those who received placebo. (Funded by AstraZeneca; ADAURA ClinicalTrials.gov number, NCT02511106.).

Time optimization of gadobutrol-enhanced brain MRI for metastases and primary tumors using a dynamic contrast-enhanced imaging.

BACKGROUND: Recent advances in rapid imaging techniques necessitate the reconsideration of the optimal imaging delay time for contrast-enhanced T1-weighted imaging. The aim of our study was to determine the optimal contrast-enhanced T1-weighted imaging delay time from the obtained time-signal intensity curve (TIC) using gadobutrol in patients with brain metastases, primary brain tumors, and meningiomas. METHODS: This prospective study enrolled 78 patients with brain metastases (n = 39), primary brain tumors (n = 22), or meningiomas (n = 17) who underwent 7-min dynamic contrast-enhanced imaging with single-dose gadobutrol. Based on the time-to-peak (TTP) derived from the TIC, we selected four different time points for analysis. Lesion conspicuity, enhanced rate (ER) and contrast rate (CR) of 116 index lesions were evaluated. Statistical comparisons were made for the four different time points using the Friedman test. RESULTS: Maximum TTP (305.20 ± 63.47 s) was similar across all three groups (p = 0.342). Lesion conspicuity, CR and ER increased over time in all index lesions; however, no significant difference between the 5- and 7-min images was observed. The longest diameter in all groups differed significantly among time points (p < 0.001); the perpendicular diameter did not differ between the 5- and 7-min images. CONCLUSIONS: Maximum contrast enhancement and lesion conspicuity was achieved 5-7 min after a single gadobutrol injection for brain metastases detection and for primary brain tumor/meningioma evaluation. Acquiring images 5 min after gadobutrol injection is the optimal timing for brain tumor detection during MRI work-up.

Targeted Next-Generation Sequencing Analysis for Recurrence in Early-Stage Lung Adenocarcinoma.

BACKGROUND: Despite surgical resection, early lung adenocarcinoma has a recurrence rate of 20-50%. No clear predictive markers for recurrence of early lung adenocarcinoma are available. Targeted next-generation sequencing (NGS) is rarely used to identify recurrence-related genes. We aimed to identify genetic alterations that can predict recurrence, by comparing the molecular profiles of patient groups with and without recurrence. METHODS: Tissues from 230 patients with resected stage I-II lung adenocarcinoma (median follow-up: 49 months) were analyzed via targeted NGS for 207 cancer-related genes. The recurrence-free survival according to the number and type of mutation was estimated using the Kaplan-Meier method. Independent predictive biomarkers related to recurrence were identified using the Cox proportional hazards model. RESULTS: Recurrence was observed in 64 patients (27.8%). In multivariate analysis adjusted for age, sex, smoking history, stage, surgical mode, and visceral pleural invasion, the CTNNB1 mutation and fusion genes (ALK, ROS1, RET) were negative prognostic factors for recurrence in early-stage lung adenocarcinoma (HR 4.47, p = 0.001; HR 2.73, p = 0.009). EGFR mutation was a favorable factor (HR 0.51, p = 0.016), but the CTNNB1/EGFR co-mutations were negative predictors (HR 19.2, p < 0.001). TP53 mutation was a negative predictor compared with EGFR mutation for recurrence (HR 5.24, p = 0.02). CONCLUSIONS: Targeted NGS can provide valuable information to predict recurrence and identify patients at high recurrence risk, facilitating selection of the treatment strategy among close monitoring and adjuvant-targeted therapy. Larger datasets are required to validate these findings.

A plain language summary of results from the ADAURA study: osimertinib after surgery for patients who have early-stage EGFR-mutated non-small cell lung cancer.

Here, we summarize the initial results from the ADAURA clinical study looking at treatment with osimertinib in patients with a specific type of non-small cell lung cancer (also called NSCLC). Osimertinib (TAGRISSO®) is a medication used to treat a type of NSCLC with a change (mutation) in the EGFR gene, known as EGFR-mutated NSCLC. EGFR stands for 'epidermal growth factor receptor'. It is a protein present on the surface of both healthy and cancer cells that can regulate how cells grow and divide. Sometimes, certain mutations in EGFR can result in the EGFR protein malfunctioning, which can lead to the formation of cancer, like EGFR-mutated NSCLC. Based on previous clinical studies, osimertinib is already approved for use in patients with EGFR-mutated NSCLC that has spread beyond the lung (metastatic disease). This medication works to stop, prevent, or slow the growth of EGFR-mutated NSCLC tumors, by specifically blocking the activity of EGFR. In the ADAURA clinical study, participants had resectable EGFR-mutated NSCLC, which means they had tumors that can be removed by surgery. Participants took either osimertinib or a placebo (a dummy drug with no active ingredient) after having their tumors removed by surgery. Post-surgery chemotherapy was allowed, but not compulsory (this was decided by the participant and their doctor). To date, the study has shown that osimertinib could be beneficial for patients with resectable EGFR-mutated NSCLC. Participants who took osimertinib have stayed cancer-free for longer than those who took the placebo, regardless of whether or not they received chemotherapy after surgery. Osimertinib treatment also reduced the risk of tumors spreading to the brain and spinal cord, otherwise known as the central nervous system (also called CNS). The side effects experienced by the participants taking osimertinib have been consistent with what we already know. Based on the results from ADAURA, osimertinib has been approved for the treatment of resectable EGFR-mutated NSCLC after tumor removal. The ADAURA study is still ongoing and more results are expected to be released in the future. ClinicalTrials.gov NCT number: NCT02511106.

Extracellular vesicle-derived DNA for performing EGFR genotyping of NSCLC patients.

Tumor cells shed an abundance of extracellular vesicles (EVs) to body fluids containing bioactive molecules including DNA, RNA, and protein. Investigations in the field of tumor-derived EVs open a new horizon in understanding cancer biology and its potential as cancer biomarkers as well as platforms for personalized medicine. This study demonstrates that successfully isolated EVs from plasma and bronchoalveolar lavage fluid (BALF) of non-small cell lung cancer (NSCLC) patients contain DNA that can be used for EGFR genotyping through liquid biopsy. In both plasma and BALF samples, liquid biopsy results using EV DNA show higher accordance with conventional tissue biopsy compared to the liquid biopsy of cfDNA. Especially, liquid biopsy with BALF EV DNA is tissue-specific and extremely sensitive compared to using cfDNA. Furthermore, use of BALF EV DNA also demonstrates higher efficiency in comparison to tissue rebiopsy for detecting p.T790 M mutation in the patients who developed resistance to EGFR-TKIs. These finding demonstrate possibility of liquid biopsy using EV DNA potentially replacing the current diagnostic methods for more accurate, cheaper, and faster results.

Cumulative smoking dose affects the clinical outcomes of EGFR-mutated lung adenocarcinoma patients treated with EGFR-TKIs: a retrospective study.

BACKGROUND: Although lung adenocarcinoma with activating epidermal growth factor receptor (EGFR) mutations is common in never smokers, one-third of the patients are ever-smokers. We aimed to investigate the effect of cumulative smoking dose(CSD) on clinical outcomes, including progression-free survival (PFS) and overall survival (OS), in patients with EGFR-mutated lung adenocarcinoma receiving EGFR-tyrosine kinase inhibitors (TKIs). METHODS: We retrospectively analyzed 142 patients with EGFR-mutation positive advanced or recurrent lung adenocarcinoma who were administered gefitinib, erlotinib, afatinib, and osimertinib. These patients were classified based on their CSD as never smokers, light smokers (≤10 pack-years [PYs]), moderate smokers (11-30 PYs), and heavy smokers (> 30 PYs). PFS and OS were analyzed according to smoking subgroups via Kaplan-Meier curves. RESULTS: Among the 142 patients, 91 (64.1%), 12 (8.5%), 22 (15.5%), and 17 (12%) were never, light, moderate, and heavy smokers, respectively. CSD was inversely associated with median PFS in a statistically significant dose-dependent manner (11.8 months (mo), 11.0 mo, 7.4 mo, and 3.9 mo; p < 0.001). Statistically significant negative association was observed between CSD and median OS (33.6 mo, 26.3 mo, 20 mo, and 8.9 mo; p < 0.001). In the multivariate analysis adjusted for age, sex, performance status, stage, and timing of EGFR-TKIs, CSD was an independent predictive factor for disease progression (hazard ratio [HR], 4.00; 95% confidence interval [CI], 1.95-8.23; p = 0.012) and OS (HR, 3.9; 95% CI, 1.84-8.28; p < 0.001). CONCLUSION: CSD is an important predictive and prognostic factor in patients with EGFR-mutated lung adenocarcinoma, and associated smoking-related gene signatures might affect the outcomes.

Liquid biopsy using the supernatant of a pleural effusion for EGFR genotyping in pulmonary adenocarcinoma patients: a comparison between cell-free DNA and extracellular vesicle-derived DNA.

BACKGROUND: EGFR genotyping in pulmonary adenocarcinoma patients who develop pleural effusions is mostly performed using cytology or cell block slides with low sensitivity. Liquid biopsy using the supernatant of pleural effusions may be more effective because they contain many components released by cancer cells. Extracellular vesicles (EVs) are known to carry oncogenic double-stranded DNA that is considered a notable biomarker. Here, we investigate the efficiency of liquid biopsy using cell-free DNA (cfDNA) and extracellular vesicle-derived DNA (EV-derived DNA) from the supernatant of pleural effusions for EGFR genotyping in patients with pulmonary adenocarcinoma. METHODS: Fifty pleural effusion samples from patients with pulmonary adenocarcinoma were evaluated. The supernatant, after removing the cell pellet by centrifugation, was used for liquid biopsy, and EVs were isolated from the pleural effusion by ultracentrifugation. EV-derived DNA and cfDNA were extracted separately, and EGFR genotyping was performed by the PNA clamping method. RESULTS: Among 32 patients who were EGFR-tyrosine kinase inhibitor (TKI) naïve with a known tissue EGFR genotype, liquid biopsy using EV-derived DNA from the pleural effusion supernatant showed 100% matching results with tissue EGFR genotyping in 19 EGFR mutant cases and detected three additional EGFR mutations in patients with wild-type (WT) tissue. Liquid biopsy using cfDNA from pleural effusion supernatants missed two cases of tissue-based EGFR mutations and found two additional EGFR mutation cases. In 18 patients who acquired resistance to EGFR-TKI, EGFR genotyping using EV-derived DNA from the pleural effusion supernatant detected the T790 M mutation in 13 of 18 (72.2%) patients, and this mutation was detected in 11 (61.1%) patients using cfDNA. By contrast, only three patients were found to present the T790 M mutation when using cell block or cytology slides. CONCLUSIONS: Liquid biopsy using the supernatant of pleural effusions showed significantly improved results for EGFR genotyping compared to those using conventional cell block or cytology samples. Liquid biopsy using EV-derived DNA is promising for EGFR genotyping, including T790 M detection in pulmonary adenocarcinoma patients who develop pleural effusions.

Fluorometric detection of EGFR exon 19 deletion mutation in lung cancer cells using graphene oxide.

Mutations in epidermal growth factor receptor (EGFR) are known as biomarkers that cause non-small cell lung cancer. Particularly, approximately 45% of non-small cell lung cancer patients possess a deletion in exon 19 of the EGFR gene. A less invasive method for detecting the EGFR mutation is required; thus, we developed a simple polymerase chain reaction (PCR)-based method for detecting EGFR exon 19 deletion by using a quencher-free fluorescent probe DNA and graphene oxide (GO). In the presence of the exon 19 deletion mutation, the fluorophore-labeled DNA probe was designed to be fully complementary to the mutant sequences. The fully annealed DNA probe was degraded by the 5' to 3' exonuclease activity of Taq DNA polymerase during PCR, releasing the fluorophore from the probe DNA. In contrast, a wild-type gene only allowed partial annealing of the probe DNA to the amplicon because of the absence of the deletion sequences, with Taq polymerase digestion releasing unannealed fragments of probe DNA. When GO was added to each reaction solution, starkly different fluorescence signals were obtained; enhanced fluorescence was observed because of the released fluorophore from the probe DNA that was not adsorbed onto GO, whereas fluorescence was quenched when the fragmented single-stranded probe DNA was readily adsorbed onto GO. Our method enabled the detection of as low as 49 pg of EGFR exon 19 deletion DNA with a detection limit of 0.1% when the mutant genomic DNA was mixed with wild-type DNA.

Assessment of EGFR mutation status using cell-free DNA from bronchoalveolar lavage fluid.

BACKGROUND: Much attention has been focused on epidermal growth factor receptor (EGFR) mutation testing since the introduction of EGFR-tyrosine kinase inhibitors have improved survival in EGFR-positive lung cancer patients. Liquid biopsy using circulating tumor cells or cell-free DNA (cfDNA) has enabled less invasive testing, but requires a highly sensitive method. To date, liquid biopsy using bronchoalveolar lavage (BAL) fluid has rarely been used. METHODS: From 20 patients with lung adenocarcinoma, we isolated cfDNA from 20 samples of cell-free BAL fluid and 19 cell-free bronchial washing samples. cfDNA was examined for EGFR mutations using peptide nucleic acid (PNA)-mediated PCR clamping method. In cases where the results from the tumor biopsy and BAL-derived cfDNA test were not consistent, PANAMutyper™ R EGFR kit was used along with PNA clamping-assisted fluorescence melting curve analysis. RESULTS: We included 17 patients with advanced stage disease and three with non-advanced stage disease. Tumor biopsy detected EGFR mutations in 12 of the patients. One patient had a p.L858R mutation and a de novo p.T790M mutation. The results from PNA-mediated PCR clamping were 75.0% (9/12) concordant with the tumor biopsy results for EGFR mutation status. PANAMutyper with fluorescence melting curve analysis was performed in three cases, which detected EGFR mutations in two more patients (11/12, 91.7%). EGFR mutations were detected in the cfDNA extracted from two bronchial washing samples. CONCLUSIONS: cfDNA from BAL fluid could be used for molecular testing of EGFR mutations and identification of p.T790M mutations, with an easily applicable method.

Belotecan/cisplatin versus etoposide/cisplatin in previously untreated patients with extensive-stage small cell lung carcinoma: a multi-center randomized phase III trial.

BACKGROUND: No novel chemotherapeutic combinations have demonstrated superior efficacy to etoposide/cisplatin (EP), a standard treatment regimen for extensive-stage small cell lung carcinoma (ES-SCLC) over the past decade. We aimed to compare the efficacy and safety of belotecan/cisplatin (BP) and EP regimens in chemotherapy- and radiotherapy-naïve patients with previously untreated ES-SCLC. METHODS: We conducted a multi-center, randomized, open-label, parallel-group, phase III clinical study. A total of 157 patients were recruited at 14 centers with 147 patients meeting the inclusion/exclusion criteria and randomized to either BP (n = 71) or EP (n = 76) treatment arms. A non-inferior response rate (RR) in the BP arm, analyzed by intent-to-treat analysis according to Response Evaluation Criteria in Solid Tumors version 1.0 criteria, was used as the primary endpoint. The secondary endpoints were progression-free survival (PFS) and overall survival (OS). RESULTS: In the BP arm, one patient had a complete response, 41 had a partial response (PR), and 17 had stable disease (SD). In the EP arm, 35 patients had PR and 28 had SD. The RR in the BP arm was non-inferior to the EP regimen in patients with ES-SCLC (BP: 59.2 %, EP: 46.1 %, difference: 13.1 %, 90 % two-sided confidence interval: -0.3-26.5, meeting the predefined non-inferiority criterion of -15.0 %). No significant differences in OS or PFS were observed between the treatment arms. Hematologic toxicities, including grade 3/4 anemia and thrombocytopenia, were significantly more prevalent in the BP arm than the EP arm. CONCLUSIONS: The RR to the BP regimen was non-inferior to the EP regimen in chemotherapy- and radiotherapy-naïve patients with previously untreated ES-SCLC. Hematologic toxicities were significantly more prevalent in the BP group, indicating that BP should be used with care, particularly in patients with a poor performance status. Further studies assessing PFS and OS are required to validate the superiority of the BP regimen. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00826644 . Date of Registration: January 21, 2009.

Detection of EGFR and KRAS Mutation by Pyrosequencing Analysis in Cytologic Samples of Non-Small Cell Lung Cancer.

EGFR and KRAS mutations are two of the most common mutations that are present in lung cancer. Screening and detecting these mutations are of issue these days, and many different methods and tissue samples are currently used to effectively detect these two mutations. In this study, we aimed to evaluate the testing for EGFR and KRAS mutations by pyrosequencing method, and compared the yield of cytology versus histology specimens in a consecutive series of patients with lung cancer. We retrospectively reviewed EGFR and KRAS mutation results of 399 (patients with EGFR mutation test) and 323 patients (patients with KRAS mutation test) diagnosed with lung cancer in Konkuk University Medical Center from 2008 to 2014. Among them, 60 patients had received both EGFR and KRAS mutation studies. We compared the detection rate of EGFR and KRAS tests in cytology, biopsy, and resection specimens. EGFR and KRAS mutations were detected in 29.8% and 8.7% of total patients, and the positive mutation results of EGFR and KRAS were mutually exclusive. The detection rate of EGFR mutation in cytology was higher than non-cytology (biopsy or resection) materials (cytology: 48.5%, non-cytology: 26.1%), and the detection rate of KRAS mutation in cytology specimens was comparable to non-cytology specimens (cytology: 8.3%, non-cytology: 8.7%). We suggest that cytology specimens are good alternatives that can readily substitute tissue samples for testing both EGFR and KRAS mutations. Moreover, pyrosequencing method is highly sensitive in detecting EGFR and KRAS mutations in lung cancer patients.

Afatinib versus cisplatin-based chemotherapy for EGFR mutation-positive lung adenocarcinoma (LUX-Lung 3 and LUX-Lung 6): analysis of overall survival data from two randomised, phase 3 trials.

BACKGROUND: We aimed to assess the effect of afatinib on overall survival of patients with EGFR mutation-positive lung adenocarcinoma through an analysis of data from two open-label, randomised, phase 3 trials. METHODS: Previously untreated patients with EGFR mutation-positive stage IIIB or IV lung adenocarcinoma were enrolled in LUX-Lung 3 (n=345) and LUX-Lung 6 (n=364). These patients were randomly assigned in a 2:1 ratio to receive afatinib or chemotherapy (pemetrexed-cisplatin [LUX-Lung 3] or gemcitabine-cisplatin [LUX-Lung 6]), stratified by EGFR mutation (exon 19 deletion [del19], Leu858Arg, or other) and ethnic origin (LUX-Lung 3 only). We planned analyses of mature overall survival data in the intention-to-treat population after 209 (LUX-Lung 3) and 237 (LUX-Lung 6) deaths. These ongoing studies are registered with ClinicalTrials.gov, numbers NCT00949650 and NCT01121393. FINDINGS: Median follow-up in LUX-Lung 3 was 41 months (IQR 35-44); 213 (62%) of 345 patients had died. Median follow-up in LUX-Lung 6 was 33 months (IQR 31-37); 246 (68%) of 364 patients had died. In LUX-Lung 3, median overall survival was 28.2 months (95% CI 24.6-33.6) in the afatinib group and 28.2 months (20.7-33.2) in the pemetrexed-cisplatin group (HR 0.88, 95% CI 0.66-1.17, p=0.39). In LUX-Lung 6, median overall survival was 23.1 months (95% CI 20.4-27.3) in the afatinib group and 23.5 months (18.0-25.6) in the gemcitabine-cisplatin group (HR 0.93, 95% CI 0.72-1.22, p=0.61). However, in preplanned analyses, overall survival was significantly longer for patients with del19-positive tumours in the afatinib group than in the chemotherapy group in both trials: in LUX-Lung 3, median overall survival was 33.3 months (95% CI 26.8-41.5) in the afatinib group versus 21.1 months (16.3-30.7) in the chemotherapy group (HR 0.54, 95% CI 0.36-0.79, p=0.0015); in LUX-Lung 6, it was 31.4 months (95% CI 24.2-35.3) versus 18.4 months (14.6-25.6), respectively (HR 0.64, 95% CI 0.44-0.94, p=0.023). By contrast, there were no significant differences by treatment group for patients with EGFR Leu858Arg-positive tumours in either trial: in LUX-Lung 3, median overall survival was 27.6 months (19.8-41.7) in the afatinib group versus 40.3 months (24.3-not estimable) in the chemotherapy group (HR 1.30, 95% CI 0.80-2.11, p=0.29); in LUX-Lung 6, it was 19.6 months (95% CI 17.0-22.1) versus 24.3 months (19.0-27.0), respectively (HR 1.22, 95% CI 0.81-1.83, p=0.34). In both trials, the most common afatinib-related grade 3-4 adverse events were rash or acne (37 [16%] of 229 patients in LUX-Lung 3 and 35 [15%] of 239 patients in LUX-Lung 6), diarrhoea (33 [14%] and 13 [5%]), paronychia (26 [11%] in LUX-Lung 3 only), and stomatitis or mucositis (13 [5%] in LUX-Lung 6 only). In LUX-Lung 3, neutropenia (20 [18%] of 111 patients), fatigue (14 [13%]) and leucopenia (nine [8%]) were the most common chemotherapy-related grade 3-4 adverse events, while in LUX-Lung 6, the most common chemotherapy-related grade 3-4 adverse events were neutropenia (30 [27%] of 113 patients), vomiting (22 [19%]), and leucopenia (17 [15%]). INTERPRETATION: Although afatinib did not improve overall survival in the whole population of either trial, overall survival was improved with the drug for patients with del19 EGFR mutations. The absence of an effect in patients with Leu858Arg EGFR mutations suggests that EGFR del19-positive disease might be distinct from Leu858Arg-positive disease and that these subgroups should be analysed separately in future trials. FUNDING: Boehringer Ingelheim.

Phospholipids of tumor extracellular vesicles stratify gefitinib-resistant nonsmall cell lung cancer cells from gefitinib-sensitive cells.

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) such as gefitinib are one of gold standard treatment options for nonsmall-cell lung cancer (NSCLC) patients, which eventually fail due to the acquired resistance and relapse because of the development of secondary activating mutations such as T790M in EGFR. Predicting chemo-responsiveness of cancer patients provides a major challenge in chemotherapy. The goal of the present study is to determine whether phospholipid signatures of tumor extracellular vesicles (EV) are associated with gefitinib-resistance of NSCLC. A sophisticated MS-based shotgun lipidomic assays were performed for in-depth analysis of the lipidomes of gefitinib-resistant (PC9R) and responsive (PC9) NSCLC cells and their shed EV from these cell lines (PC9EV or PC9REV). Lipid MALDI-MS analysis showed that EV phospholipid composition was significantly distinct in PC9R, compared to PC9 cells. Following statistical analyses has identified 35 (20 positive and 15 negative ion mode) differentially regulated lipids, which are significantly over- or underexpressed in PC9R EV, compared to PC9 EV (p value < 0.01, fold change > 1.5). Our phospholipid signatures suggest that EV associates with drug sensitivity, which is worthy of additional investigation to assess chemoresistance in patients with NSCLC treated with anti-EGFR TKIs.

P-glycoprotein confers acquired resistance to 17-DMAG in lung cancers with an ALK rearrangement.

BACKGROUND: Because anaplastic lymphoma kinase (ALK) is dependent on Hsp90 for protein stability, Hsp90 inhibitors are effective in controlling growth of lung cancer cells with ALK rearrangement. We investigated the mechanism of acquired resistance to 17-(Dimethylaminoethylamino)-17-demethoxygeldanamycin (17-DMAG), a geldanamycin analogue Hsp90 inhibitor, in H3122 and H2228 non-small cell lung cancer cell lines with ALK rearrangement. METHODS: Resistant cell lines (H3122/DR-1, H3122/DR-2 and H2228/DR) were established by repeated exposure to increasing concentrations of 17-DMAG. Mechanisms for resistance by either NAD(P)H/quinone oxidoreductase 1 (NQO1), previously known as a factor related to 17-DMAG resistance, or P-glycoprotein (P-gp; ABCB1/MDR1) were queried using RT-PCR, western blot analysis, chemical inhibitors, the MTT cell proliferation/survival assay, and cellular efflux of rhodamine 123. RESULTS: The resistant cells showed no cross-resistance to AUY922 or ALK inhibitors, suggesting that ALK dependency persists in cells with acquired resistance to 17-DMAG. Although expression of NQO1 was decreased in H3122/DR-1 and H3122/DR-2, NQO1 inhibition by dicumarol did not affect the response of parental cells (H2228 and H3122) to 17-DMAG. Interestingly, all resistant cells showed the induction of P-gp at the protein and RNA levels, which was associated with an increased efflux of the P-gp substrate rhodamine 123 (Rho123). Transfection with siRNA directed against P-gp or treatment with verapamil, an inhibitor of P-gp, restored the sensitivity to the drug in all cells with acquired resistance to 17-DMAG. Furthermore, we also observed that the growth-inhibitory effect of 17-DMAG was decreased in A549/PR and H460/PR cells generated to over-express P-gp by long-term exposure to paclitaxel, and these cells recovered their sensitivity to 17-DMAG through the inhibition of P-gp. CONCLUSION: P-gp over-expression is a possible mechanism of acquired resistance to 17-DMAG in cells with ALK rearrangement.

Afatinib versus cisplatin plus gemcitabine for first-line treatment of Asian patients with advanced non-small-cell lung cancer harbouring EGFR mutations (LUX-Lung 6): an open-label, randomised phase 3 trial.

BACKGROUND: Afatinib-an oral irreversible ErbB family blocker-improves progression-free survival compared with pemetrexed and cisplatin for first-line treatment of patients with EGFR mutation-positive advanced non-small-cell lung cancer (NSCLC). We compared afatinib with gemcitabine and cisplatin-a chemotherapy regimen widely used in Asia-for first-line treatment of Asian patients with EGFR mutation-positive advanced NSCLC. METHODS: This open-label, randomised phase 3 trial was done at 36 centres in China, Thailand, and South Korea. After central testing for EGFR mutations, treatment-naive patients (stage IIIB or IV cancer [American Joint Committee on Cancer version 6], performance status 0-1) were randomly assigned (2:1) to receive either oral afatinib (40 mg per day) or intravenous gemcitabine 1000 mg/m(2) on day 1 and day 8 plus cisplatin 75 mg/m(2) on day 1 of a 3-week schedule for up to six cycles. Randomisation was done centrally with a random number-generating system and an interactive internet and voice-response system. Randomisation was stratified by EGFR mutation (Leu858Arg, exon 19 deletions, or other; block size three). Clinicians and patients were not masked to treatment assignment, but the independent central imaging review group were. Treatment continued until disease progression, intolerable toxic effects, or withdrawal of consent. The primary endpoint was progression-free survival assessed by independent central review (intention-to-treat population). This study is registered with ClinicalTrials.gov, NCT01121393. FINDINGS: 910 patients were screened and 364 were randomly assigned (242 to afatinib, 122 to gemcitabine and cisplatin). Median progression-free survival was significantly longer in the afatinib group (11·0 months, 95% CI 9·7-13·7) than in the gemcitabine and cisplatin group (5·6 months, 5·1-6·7; hazard ratio 0·28, 95% CI 0·20-0·39; p<0·0001). The most common treatment-related grade 3 or 4 adverse events in the afatinib group were rash or acne (35 [14·6%] of 239 patients), diarrhoea (13 [5·4%]), and stomatitis or mucositis (13 [5·4%]), compared with neutropenia (30 [26·5%] of 113 patients), vomiting (22 [19·5%]), and leucopenia (17 [15·0%]) in the gemcitabine and cisplatin group. Treatment-related serious adverse events occurred in 15 (6·3%) patients in the afatinib group and nine (8·0%) patients in the gemcitabine and cisplatin group. INTERPRETATION: First-line afatinib significantly improves progression-free survival with a tolerable and manageable safety profile in Asian patients with EGFR mutation-positive advanced lung NSCLC. Afatinib should be considered as a first-line treatment option for this patient population. FUNDING: Boehringer Ingelheim.

Extracellular vesicles shed from gefitinib-resistant nonsmall cell lung cancer regulate the tumor microenvironment.

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs), including gefitinib, are the first-line treatment of choice for nonsmall cell lung cancer patients who harbor activating EGFR mutations, however, acquired resistance to EGFR-TKIs is inevitable. The main objective of this study was to identify informative protein signatures of extracellular vesicles (EV) derived from gefitinib-resistant nonsmall cell lung cancer cells using proteomics analysis. Nano-LC-MS/MS analysis identified with high confidence (false discovery rate < 0.05, fold change ≥2) 664 EV proteins enriched in PC9R cells, which are resistant to gefitinib due to EGFR T790M mutation. Computational analyses suggested components of several signal transduction mechanisms including the AKT (also PKB, protein kinase B)/mTOR (mechanistic target of rapamycin) pathway are overrepresented in EV from PC9R cells. Treatment of recipient cells with EV harvested from PC9R cells increased phosphorylation of signaling molecules, and enhanced proliferation, invasion, and drug resistance to gefitinib-induced apoptosis. Dose- and time-dependent pharmaceutical inhibition of AKT/mTOR pathway overcame drug resistance of PC9R cells and those of H1975 exhibiting EGFR T790M mutation. Our findings provide new insight into an oncogenic EV protein signature regulating tumor microenvironment, and will aid in the development of novel diagnostic strategies for prediction and assessment of gefitinib resistance.

Real-World Outcomes of Crizotinib in ROS1-Rearranged Advanced Non-Small-Cell Lung Cancer.

Real-world data on the use and outcomes of crizotinib in ROS1-rearranged non-small-cell lung cancer (NSCLC) are limited. This study aims to analyze the real-world efficacy of crizotinib in South Korea and explore the utilization of liquid biopsies that implement next-generation sequencing (NGS) using cell-free total nucleic acids. In this prospective multicenter cohort study, 40 patients with ROS1-rearranged NSCLC, either starting or already on crizotinib, were enrolled. Patients had a median age of 61 years, with 32.5% presenting brain/central nervous system (CNS) metastases at treatment initiation. At the data cutoff, 48.0% were still in treatment; four continued with it even after disease progression due to the clinical benefits. The objective response rate was 70.0%, with a median duration of response of 27.8 months. The median progression-free survival was 24.1 months, while the median overall survival was not reached. Adverse events occurred in 90.0% of patients, primarily with elevated transaminases, yet these were mostly manageable. The NGS assay detected a CD74-ROS1 fusion in 2 of the 14 patients at treatment initiation and identified emerging mutations, such as ROS1 G2032R, ROS1 D2033N, and KRAS G12D, during disease progression. These findings confirm crizotinib's sustained clinical efficacy and safety in a real-world context, which was characterized by a higher elderly population and higher rates of brain/CNS metastases. The study highlights the clinical relevance of liquid biopsy for detecting resistance mechanisms, suggesting its value in personalized treatment strategies.

Real-world outcome of crizotinib for anaplastic lymphoma kinase-positive lung cancer: Multicenter retrospective analysis in South Korea.

BACKGROUND: About 3%-5% of non-small cell lung cancer (NSCLC) presents positive anaplastic lymphoma kinase (ALK). Recently, several target agents have been approved as a treatment for ALK-positive NSCLC. This study aimed to analyze the real-world efficacy and outcome when administered crizotinib, the first approved target agent for ALK-positive NSCLC, according to first- or late-line treatment. METHODS: A total of 290 patients with ALK-positive advanced NSCLC who were treated with crizotinib in 15 institutions in South Korea from January 2009 to December 2018 were enrolled. RESULTS: The median age of patients was 57.0 years, and 50.3% were male. The median follow-up duration was 29.3 months. Among them, 113 patients received crizotinib as first-line therapy. The objective response rate (ORR) was 60.1% (57.0% for first-line recipients, 61.8% for second-/later-line). Median (95% CI) progression-free survival (PFS) was 13.7 (11.6-17.0) months. For first-line recipients, overall survival (OS) was 26.3 (17.6-35.0) months. No significant difference in ORR, PFS and OS, according to the setting of crizotinib initiation, was observed. In a multivariate Cox regression analysis, old age, male gender, initially metastatic, and number of metastatic organs were associated with poor PFS and OS. The most common adverse events were nausea and vomiting, and severe adverse event leading to dose adjustment was hepatotoxicity. CONCLUSIONS: ORR, PFS, OS, and adverse event profiles were comparable to previous clinical trials. Our findings could aid in the efficient management of ALK-positive lung cancer patients.

Identification and characterization of proteins isolated from microvesicles derived from human lung cancer pleural effusions.

Microvesicles (MVs, also known as exosomes, ectosomes, microparticles) are released by various cancer cells, including lung, colorectal, and prostate carcinoma cells. MVs released from tumor cells and other sources accumulate in the circulation and in pleural effusion. Although recent studies have shown that MVs play multiple roles in tumor progression, the potential pathological roles of MV in pleural effusion, and their protein composition, are still unknown. In this study, we report the first global proteomic analysis of highly purified MVs derived from human nonsmall cell lung cancer (NSCLC) pleural effusion. Using nano-LC-MS/MS following 1D SDS-PAGE separation, we identified a total of 912 MV proteins with high confidence. Three independent experiments on three patients showed that MV proteins from PE were distinct from MV obtained from other malignancies. Bioinformatics analyses of the MS data identified pathologically relevant proteins and potential diagnostic makers for NSCLC, including lung-enriched surface antigens and proteins related to epidermal growth factor receptor signaling. These findings provide new insight into the diverse functions of MVs in cancer progression and will aid in the development of novel diagnostic tools for NSCLC.