Showing papers by "Byoung Chul Cho published in 2018"

Osimertinib in Untreated EGFR-Mutated Advanced Non–Small-Cell Lung Cancer

Abstract: BackgroundOsimertinib is an oral, third-generation, irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) that selectively inhibits both EGFR-TKI–sensitizing and EGFR T790M resistance mutations. We compared osimertinib with standard EGFR-TKIs in patients with previously untreated, EGFR mutation–positive advanced non–small-cell lung cancer (NSCLC). MethodsIn this double-blind, phase 3 trial, we randomly assigned 556 patients with previously untreated, EGFR mutation–positive (exon 19 deletion or L858R) advanced NSCLC in a 1:1 ratio to receive either osimertinib (at a dose of 80 mg once daily) or a standard EGFR-TKI (gefitinib at a dose of 250 mg once daily or erlotinib at a dose of 150 mg once daily). The primary end point was investigator-assessed progression-free survival. ResultsThe median progression-free survival was significantly longer with osimertinib than with standard EGFR-TKIs (18.9 months vs. 10.2 months; hazard ratio for disease progression or death, 0.46; 95% confi...

CNS Response to Osimertinib Versus Standard Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors in Patients With Untreated EGFR-Mutated Advanced Non–Small-Cell Lung Cancer

Abstract: Purpose We report CNS efficacy of osimertinib versus standard epidermal growth factor receptor ( EGFR) tyrosine kinase inhibitors (TKIs) in patients with untreated EGFR-mutated advanced non-small-cell lung cancer from the phase III FLAURA study. Patients and Methods Patients (N = 556) were randomly assigned to osimertinib or standard EGFR-TKIs (gefitinib or erlotinib); brain scans were not mandated unless clinically indicated. Patients with asymptomatic or stable CNS metastases were included. In patients with symptomatic CNS metastases, neurologic status was required to be stable for ≥ 2 weeks after completion of definitive therapy and corticosteroids. A preplanned subgroup analysis with CNS progression-free survival as primary objective was conducted in patients with measurable and/or nonmeasurable CNS lesions on baseline brain scan by blinded independent central neuroradiologic review. The CNS evaluable-for-response set included patients with ≥ one measurable CNS lesion. Results Of 200 patients with available brain scans at baseline, 128 (osimertinib, n = 61; standard EGFR-TKIs, n = 67) had measurable and/or nonmeasurable CNS lesions, including 41 patients (osimertinib, n = 22; standard EGFR-TKIs, n = 19) with ≥ one measurable CNS lesion. Median CNS progression-free survival in patients with measurable and/or nonmeasurable CNS lesions was not reached with osimertinib (95% CI, 16.5 months to not calculable) and 13.9 months (95% CI, 8.3 months to not calculable) with standard EGFR-TKIs (hazard ratio, 0.48; 95% CI, 0.26 to 0.86; P = .014 [nominally statistically significant]). CNS objective response rates were 91% and 68% in patients with ≥ one measurable CNS lesion (odds ratio, 4.6; 95% CI, 0.9 to 34.9; P = .066) and 66% and 43% in patients with measurable and/or nonmeasurable CNS lesions (odds ratio, 2.5; 95% CI, 1.2 to 5.2; P = .011) treated with osimertinib and standard EGFR-TKIs, respectively. Probability of experiencing a CNS progression event was consistently lower with osimertinib versus standard EGFR-TKIs. Conclusion Osimertinib has CNS efficacy in patients with untreated EGFR-mutated non-small-cell lung cancer. These results suggest a reduced risk of CNS progression with osimertinib versus standard EGFR-TKIs.

Repotrectinib (TPX-0005) Is a Next-Generation ROS1/TRK/ALK Inhibitor That Potently Inhibits ROS1/TRK/ALK Solvent- Front Mutations

Abstract: The use of tyrosine kinase inhibitors (TKI) with activity against ALK, ROS1, or TRKA–C can result in significant clinical benefit in patients with diverse tumors harboring ALK, ROS1, or NTRK1–3 rearrangements; however, resistance invariably develops. The emergence of on-target kinase domain mutations represents a major mechanism of acquired resistance. Solvent-front substitutions such as ALKG1202R, ROS1G2032R or ROS1D2033N, TRKAG595R, and TRKCG623R are among the most recalcitrant of these mechanisms. Repotrectinib (TPX-0005) is a rationally designed, low-molecular-weight, macrocyclic TKI that is selective and highly potent against ROS1, TRKA–C, and ALK. Importantly, repotrectinib exhibits activity against a variety of solvent-front substitutions in vitro and in vivo. As clinical proof of concept, in an ongoing first-in-human phase I/II trial, repotrectinib achieved confirmed responses in patients with ROS1 or NTRK3 fusion–positive cancers who had relapsed on earlier-generation TKIs due to ROS1 or TRKC solvent-front substitution-mediated resistance. SIGNIFICANCE: Repotrectinib (TPX-0005), a next-generation ROS1, pan-TRK, and ALK TKI, overcomes resistance due to acquired solvent-front mutations involving ROS1, NTRK1–3, and ALK. Repotrectinib may represent an effective therapeutic option for patients with ROS1-, NTRK1–3-, or ALK-rearranged malignancies who have progressed on earlier-generation TKIs. Cancer Discov; 8(10); 1–10. ©2018 AACR.

Pembrolizumab (pembro) versus platinum-based chemotherapy (chemo) as first-line therapy for advanced/metastatic NSCLC with a PD-L1 tumor proportion score (TPS) ≥ 1%: Open-label, phase 3 KEYNOTE-042 study.

Abstract: LBA4Background: In KEYNOTE-024, pembro significantly improved PFS (primary end point) and OS (secondary end-point) over chemo as first-line therapy for metastatic NSCLC without targetable alterations and PD-L1 TPS ≥50%. In KEYNOTE-042, we compared pembro with chemo at the lower TPS of ≥1% (NCT02220894). Methods: Eligible patients (pts) were randomized 1:1 to ≤35 cycles of pembro 200 mg Q3W or investigator’s choice of ≤6 cycles of paclitaxel + carboplatin or pemetrexed (peme) + carboplatin with optional peme maintenance (nonsquamous only). Randomization was stratified by region (east Asia vs non-east Asia), ECOG PS (0 vs 1), histology (squamous vs nonsquamous), and TPS (≥50% vs 1-49%). Primary end-points were OS in pts with TPS ≥50%, ≥20%, and ≥1%. OS differences were assessed sequentially using the stratified log-rank test. Efficacy boundaries at the prespecified second interim analysis were one-sided P = .0122, .01198, and .01238, respectively. Results: 1274 pts were randomized: 637 to each arm. 599 pts ...

Impact of Tumor Purity on Immune Gene Expression and Clustering Analyses across Multiple Cancer Types

Abstract: Surgical archives of tumor specimens are often impure. The presence of RNA transcripts from nontumor cells, such as immune and stromal cells, can impede analyses of cancer expression profiles. To systematically analyze the impact of tumor purity, the gene expression profiles and tumor purities were obtained for 7,794 tumor specimens across 21 tumor types (available in The Cancer Genome Atlas consortium). First, we observed that genes with roles in immunity and oxidative phosphorylation were significantly inversely correlated and correlated with the tumor purity, respectively. The expression of genes implicated in immunotherapy and specific immune cell genes, along with the abundance of immune cell infiltrates, was substantially inversely correlated with tumor purity. This relationship may explain the correlation between immune gene expression and mutation burden, highlighting the need to account for tumor purity in the evaluation of expression markers obtained from bulk tumor transcriptome data. Second, examination of cluster membership of gene pairs, with or without controlling for tumor purity, revealed that tumor purity may have a substantial impact on gene clustering across tumor types. Third, feature genes for molecular taxonomy were analyzed for correlation with tumor purity, and for some tumor types, feature genes representing the mesenchymal and classical subtypes were inversely correlated and correlated with tumor purity, respectively. Our findings indicate that tumor purity is an important confounder in evaluating the correlation between gene expression and clinicopathologic features such as mutation burden, as well as gene clustering and molecular taxonomy. Cancer Immunol Res; 6(1); 87–97. ©2017 AACR .

Updated efficacy and safety data from the global phase III ALEX study of alectinib (ALC) vs crizotinib (CZ) in untreated advanced ALK+ NSCLC.

Abstract: 9043Background: The primary ALEX (NCT02075840) analysis showed superior investigator (INV)-assessed PFS with ALC vs CZ (HR 047, 95% CI 034–065, p<0001; median 111 months [m] CZ, not estimable

Enhancer Remodeling and MicroRNA Alterations Are Associated with Acquired Resistance to ALK Inhibitors

Abstract: Anaplastic lymphoma kinase (ALK) inhibitors are highly effective in patients with ALK fusion-positive lung cancer, but acquired resistance invariably emerges. Identification of secondary mutations has received considerable attention, but most cases cannot be explained by genetic causes alone, raising the possibility of epigenetic mechanisms in acquired drug resistance. Here, we investigated the dynamic changes in the transcriptome and enhancer landscape during development of acquired resistance to ALK inhibitors. Histone H3 lysine 27 acetylation (H3K27ac) was profoundly altered during acquisition of resistance, and enhancer remodeling induced expression changes in both miRNAs and mRNAs. Decreased H3K27ac levels and reduced miR-34a expression associated with the activation of target genes such as AXL. Panobinostat, a pan-histone deacetylase inhibitor, altered the H3K27ac profile and activated tumor-suppressor miRNAs such as miR-449, another member of the miR-34 family, and synergistically induced antiproliferative effects with ALK inhibitors on resistant cells, xenografts, and EML4-ALK transgenic mice. Paired analysis of patient samples before and after treatment with ALK inhibitors revealed that repression of miR-34a or miR-449a and activation of AXL were mutually exclusive of secondary mutations in ALK. Our findings indicate that enhancer remodeling and altered expression of miRNAs play key roles in cancer drug resistance and suggest that strategies targeting epigenetic pathways represent a potentially effective method for overcoming acquired resistance to cancer therapy.Significance: Epigenetic deregulation drives acquired resistance to ALK inhibitors in ALK-positive lung cancer. Cancer Res; 78(12); 3350-62. ©2018 AACR.

ERK-dependent IL-6 autocrine signaling mediates adaptive resistance to pan-PI3K inhibitor BKM120 in head and neck squamous cell carcinoma.

Abstract: Hyperactivation of phosphatidylinositol 3-kinase (PI3K) pathway occurs frequently in head and neck squamous cell carcinoma (HNSCC). However, clinical outcomes of targeting the PI3K pathway have been underwhelming. In present study, we investigated the resistant mechanisms and potential combination therapeutic strategy to overcome adaptive resistance to PI3K inhibitor in HNSCC. Treatment of NVP-BKM120, a pan-PI3K inhibitor, led to upregulation of interleukin-6 (IL-6) and subsequent activation of either extracellular signal-regulated kinase (ERK) or signal transducers and activators of transcription 3 (STAT3), causing modest antitumor effects on the growth of HNSCC cells. Blockade of autocrine IL-6 signaling with siRNA or neutralizing antibody for IL-6 receptor (IL-6R) completely abolished NVP-BKM120-induced activation of ERK and STAT3 as well as expression of c-Myc oncogene, which resulted in enhanced sensitivity to NVP-BKM120. Moreover, when compared with a pharmacologic inhibitor or silencing of STAT3, trametinib, a MEK inhibitor, in combination with NVP-BKM120 yielded more potent anti-proliferative effects by inhibiting S phase transition, arresting cells at G0/G1 phase, and downregulating IL-6 and c-Myc expression. Furthermore, as compared with either agent alone, combination of NVP-BKM120 with trametinib or tocilizumab, a humanized anti-IL-6R antibody, significantly suppressed tumor growth in NVP-BKM120-resistant patient-derived tumor xenograft (PDTX) models, which was also confirmed in PDTX-derived cell lines. Collectively, these results suggested that IL-6/ERK signaling is closely involved in adaptive resistance of NVP-BKM120 in HNSCC cells, providing a rationale for a novel combination therapy to overcome resistance to PI3K inhibitors.

Efficacy and safety of vinorelbine plus cisplatin chemotherapy for patients with recurrent and/or metastatic salivary gland cancer of the head and neck

Abstract: Background The purpose of this study was to investigate the efficacy and safety of vinorelbine plus cisplatin chemotherapy in patients with recurrent and/or metastatic salivary gland cancer of the head and neck. Methods In this single-arm phase II study, patients with recurrent and/or metastatic salivary gland cancer were treated with i.v. vinorelbine (25 mg/m2) on days 1 and 8 plus cisplatin (80 mg/m2) on day 1 every 3 weeks for 4 or 6 cycles. The primary endpoint was the objective response rate. Progression-free survival (PFS), overall survival (OS), and adverse events were also assessed. Results Between September 2008 and November 2014, 40 patients with recurrent and/or metastatic salivary gland cancer received vinorelbine plus cisplatin chemotherapy. The objective response rate was 35.0%, including 1 complete response. Median PFS and OS rates were 6.3 months and 16.9 months, respectively. No treatment-related deaths occurred. Conclusion Administering vinorelbine plus cisplatin chemotherapy to patients with recurrent and/or metastatic salivary gland cancers is safe and effective.

RNF25 promotes gefitinib resistance in EGFR-mutant NSCLC cells by inducing NF-κB-mediated ERK reactivation.

Abstract: Non-small cell lung cancer (NSCLC) patients with EGFR mutations initially respond well to EGFR tyrosine kinase inhibitors (TKIs) but eventually exhibit acquired or innate resistance to the therapies typically due to gene mutations, such as EGFR T790M mutation or a second mutation in the downstream pathways of EGFR. Importantly, a significant portion of NSCLC patients shows TKI resistance without any known mechanisms, calling more comprehensive studies to reveal the underlying mechanisms. Here, we investigated a synthetic lethality with gefitinib using a genome-wide RNAi screen in TKI-resistant EGFR-mutant NSCLC cells, and identified RNF25 as a novel factor related to gefitinib resistance. Depletion of RNF25 expression substantially sensitized NSCLC cells to gefitinib treatment, while forced expression of RNF25 augmented gefitinib resistance in sensitive cells. We demonstrated that RNF25 mediates NF-κB activation in gefitinib-treated cells, which, in turn, induces reactivation of ERK signal to cause the drug resistance. We identified that the ERK reactivation occurs via the function of cytokines, such as IL-6, whose expression is transcriptionally induced in a gefitinib-dependent manner by RNF25-mediated NF-κB signals. These results suggest that RNF25 plays an essential role in gefitinib resistance of NSCLC by mediating cross-talk between NF-κB and ERK pathways, and provide a novel target for the combination therapy to overcome TKI resistance of NSCLC.

Profiling of protein–protein interactions via single-molecule techniques predicts the dependence of cancers on growth-factor receptors

Abstract: The accumulation of genetic and epigenetic alterations in cancer cells rewires cellular signalling pathways through changes in the patterns of protein–protein interactions (PPIs). Understanding these patterns may facilitate the design of tailored cancer therapies. Here, we show that single-molecule pull-down and co-immunoprecipitation techniques can be used to characterize signalling complexes of the human epidermal growth-factor receptor (HER) family in specific cancers. By analysing cancer-specific signalling phenotypes, including post-translational modifications and PPIs with downstream interactions, we found that activating mutations of the epidermal growth-factor receptor (EGFR) gene led to the formation of large protein complexes surrounding mutant EGFR proteins and to a reduction in the dependency of mutant EGFR signalling on phosphotyrosine residues, and that the strength of HER-family PPIs is correlated with the strength of the dependence of breast and lung adenocarcinoma cells on HER-family signalling pathways. Furthermore, using co-immunoprecipitation profiling to screen for EGFR-dependent cancers, we identified non-small-cell lung cancers that respond to an EGFR-targeted inhibitor. Our approach might help predict responses to targeted cancer therapies, particularly for cancers that lack actionable genomic mutations.

Characterization of head and neck squamous cell carcinoma arising in young patients: Particular focus on molecular alteration and tumor immunity

Abstract: BACKGROUND The purpose of this study was to comprehensively characterize head and neck squamous cell carcinoma (HNSCC) arising in young patients (<45 years old). METHODS We performed immunohistochemistry, silver, and fluorescence in situ hybridization using samples obtained from 396 radically resected cases among 1787 HNSCCs. RESULTS Young age HNSCCs occurred in 10.9% (194/1787) and were most common in the oral tongue (50.5%). They revealed distinctively lower frequency of p16 positivity, high c-MET expression, MET copy number gain, and lower pan-Trk expression. PD-L1 positivity in tumor cells and ICOS+ tumor infiltrating lymphocytes (TILs) were higher in the young age. Perineural invasion, PD-L1 positivity, and higher ratio of CD163+ tumor infiltrating macrophages to CD8 + TILs were determined to be independent factors for poor progression-free survival. CONCLUSION Characterizing these features of young age HNSCC may help to identify the underlying pathogenesis and to improve patient outcome through different treatment strategies.

A phase 1 study of the next-generation ALK/ROS1/TRK inhibitor ropotrectinib (TPX-0005) in patients with advanced ALK/ROS1/NTRK+ cancers (TRIDENT-1).

Abstract: 2513Background: Pts with ALK/ROS1/NTRK fusion-positive cancers can develop on-target TKI resistance [e.g. solvent front mutations (SFMs)] and/or central nervous system (CNS) relapse. Ropotrectinib ...

A Clinical Trial of Combination Neoadjuvant Chemotherapy and Transoral Robotic Surgery in Patients with T3 and T4 Laryngo-Hypopharyngeal Cancer

Abstract: We conducted a prospective clinical trial of combination neoadjuvant chemotherapy, transoral robotic surgery (TORS), and customized adjuvant therapy in patients with locally advanced laryngo-hypopharyngeal cancer. Between September 2008 and August 2016, 35 patients were enrolled in this clinical trial. Twenty patients had hypopharyngeal cancer and 15 had laryngeal cancer. Twenty-nine patients (82.9%) had T3 disease and six patients (17.1%) had T4 disease, while 12 patients (34.3%) had stage III disease and 23 patients (65.7%) had stage IV disease. The 3-year disease-specific survival rate was 82.4% and the 3-year disease-free survival rate was 69.48%. Decannulation was successful in 31 of 34 patients at an average of 18 days postoperatively. Among all patients, 83% exhibited a favorable subjective swallowing status, while five patients (14.4%) became dependent on feeding tubes. Neoadjuvant chemotherapy combined with TORS and customized adjuvant therapy, based on detailed pathological information, afforded favorable oncological outcomes and preserved organ functionalities in T3–T4 laryngo-hypopharyngeal cancer.

Molecular Screening of Small Biopsy Samples Using Next-Generation Sequencing in Korean Patients with Advanced Non-small Cell Lung Cancer: Korean Lung Cancer Consortium (KLCC-13-01)

Abstract: BACKGROUND Non-small cell lung cancer (NSCLC) is a common type of cancer with poor prognosis. As individual cancers exhibit unique mutation patterns, identifying and characterizing gene mutations in NSCLC might help predict patient outcomes and guide treatment. The aim of this study was to evaluate the clinical adequacy of molecular testing using next-generation sequencing (NGS) for small biopsy samples and characterize the mutational landscape of Korean patients with advanced NSCLC. METHODS DNA was extracted from small biopsy samples of 162 patients with advanced NSCLC. Targeted NGS of genomic alterations was conducted using Ion AmpliSeq Cancer Hotspot Panel v2. RESULTS The median age of patients was 64 years (range, 32 to 83 years) and the majority had stage IV NSCLC at the time of cancer diagnosis (90%). Among the 162 patients, 161 patients (99.4%) had novel or hotspot mutations (range, 1 to 21 mutated genes). Mutations were found in 41 genes. Three of the most frequently mutated genes were TP53 (151, 93.2%), KDR (104, 64.2%), and epidermal growth factor receptor (EGFR; 69, 42.6%). We also observed coexistence of EGFR and other oncogene (such as KRAS, PIC3CA, PTEN, and STK11) mutations. Given that 69.6% (48/69) of EGFR mutant patients were treated with EGFR tyrosine kinase inhibitors, EGFR mutant status had higher prognostic ability in this study. CONCLUSIONS These results suggest that targeted NGS using small biopsy samples is feasible and allows for the detection of both common and rare mutations in NSCLC.

Results from a second-line (2L) NSCLC cohort treated with M7824 (MSB0011359C), a bifunctional fusion protein targeting TGF-β and PD-L1.

Abstract: 9017Background: Inhibiting the transforming growth factor β (TGF-β) pathway, which promotes tumor immunosuppression, may enhance the response to PD-(L)1 monoclonal antibodies (mAbs). 2L+ overall re...