EGFR-mutated lung cancers account for a significant subgroup of non-small cell lung cancers overall. Third-generation EGFR tyrosine kinase inhibitors (TKI) are mutation-selective inhibitors with ...minimal effects on wild-type EGFR. Acquired resistance develops to these agents, however, the mechanisms are as yet uncharacterized. In this study, we report that the Src-AKT pathway contributes to acquired resistance to these TKI. In addition, amplification of EGFR wild-type alleles but not mutant alleles was sufficient to confer acquired resistance. These findings underscore the importance of signals from wild-type EGFR alleles in acquiring resistance to mutant-selective EGFR-TKI. Our data provide evidence of wild-type allele-mediated resistance, a novel concept of acquired resistance in response to mutation-selective inhibitor therapy in cancer treatment.
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Summary Background Alectinib, a potent, highly selective, CNS-active inhibitor of anaplastic lymphoma kinase (ALK), showed promising efficacy and tolerability in the single-arm phase 1/2 AF-001JP ...trial in Japanese patients with ALK -positive non-small-cell lung cancer. Given those promising results, we did a phase 3 trial to directly compare the efficacy and safety of alectinib and crizotinib. Methods J-ALEX was a randomised, open-label, phase 3 trial that recruited ALK inhibitor-naive Japanese patients with ALK -positive non-small-cell lung cancer, who were chemotherapy-naive or had received one previous chemotherapy regimen, from 41 study sites in Japan. Patients were randomly assigned (1:1) via an interactive web response system using a permuted-block method stratified by Eastern Cooperative Oncology Group performance status, treatment line, and disease stage to receive oral alectinib 300 mg twice daily or crizotinib 250 mg twice daily until progressive disease, unacceptable toxicity, death, or withdrawal. The primary endpoint was progression-free survival assessed by an independent review facility. The efficacy analysis was done in the intention-to-treat population, and safety analyses were done in all patients who received at least one dose of the study drug. The study is ongoing and patient recruitment is closed. This study is registered with the Japan Pharmaceutical Information Center (number JapicCTI-132316). Findings Between Nov 18, 2013, and Aug 4, 2015, 207 patients were recruited and assigned to the alectinib (n=103) or crizotinib (n=104) groups. At data cutoff for the second interim analysis, 24 patients in the alectinib group had discontinued treatment compared with 61 in the crizotinib group, mostly due to lack of efficacy or adverse events. At the second interim analysis (data cutoff date Dec 3, 2015), an independent data monitoring committee determined that the primary endpoint of the study had been met (hazard ratio 0·34 99·7% CI 0·17–0·71, stratified log-rank p<0·0001) and recommended an immediate release of the data. Median progression-free survival had not yet been reached with alectinib (95% CI 20·3–not estimated) and was 10·2 months (8·2–12·0) with crizotinib. Grade 3 or 4 adverse events occurred at a greater frequency with crizotinib (54 52% of 104) than alectinib (27 26% of 103). Dose interruptions due to adverse events were also more prevalent with crizotinib (77 74% of 104) than with alectinib (30 29% of 103), and more patients receiving crizotinib (21 20%) than alectinib (nine 9%) discontinued the study drug because of an adverse event. No adverse events with a fatal outcome occurred in either treatment group. Interpretation These results provide the first head-to-head comparison of alectinib and crizotinib and have the potential to change the standard of care for the first-line treatment of ALK -positive non-small-cell lung cancer. The dose of alectinib (300 mg twice daily) used in this study is lower than the approved dose in countries other than Japan; however, this limitation is being addressed in the ongoing ALEX study. Funding Chugai Pharmaceutical Co, Ltd.
Summary Background Results from a previous phase 3 study suggested that prophylactic cranial irradiation reduces the incidence of symptomatic brain metastases and prolongs overall survival compared ...with no prophylactic cranial irradiation in patients with extensive-disease small-cell lung cancer. However, because of the absence of brain imaging before enrolment and variations in chemotherapeutic regimens and irradiation doses, concerns have been raised about these findings. We did a phase 3 trial to reassess the efficacy of prophylactic cranial irradiation in the treatment of extensive-disease small-cell lung cancer. Methods We did this randomised, open-label, phase 3 study at 47 institutions in Japan. Patients with extensive-disease small-cell lung cancer who had any response to platinum-based doublet chemotherapy and no brain metastases on MRI were randomly assigned (1:1) to receive prophylactic cranial irradiation (25 Gy in ten daily fractions of 2·5 Gy) or observation. All patients were required to have brain MRI at 3-month intervals up to 12 months and at 18 and 24 months after enrolment. Randomisation was done by computer-generated allocation sequence, with age as a stratification factor and minimisation by institution, Eastern Cooperative Oncology Group performance status, and response to initial chemotherapy. The primary endpoint was overall survival, analysed in the intention-to-treat population. This trial is registered with the UMIN Clinical Trials Registry, number UMIN000001755, and is closed to new participants. Findings Between April 3, 2009, and July 17, 2013, 224 patients were enrolled and randomly assigned (113 to prophylactic cranial irradiation and 111 to observation). In the planned interim analysis on June 18, 2013, of the first 163 enrolled patients, Bayesian predictive probability of prophylactic cranial irradiation being superior to observation was 0·011%, resulting in early termination of the study because of futility. In the final analysis, median overall survival was 11·6 months (95% CI 9·5–13·3) in the prophylactic cranial irradiation group and 13·7 months (10·2–16·4) in the observation group (hazard ratio 1·27, 95% CI 0·96–1·68; p=0·094). The most frequent grade 3 or worse adverse events at 3 months were anorexia (six 6% of 106 in the prophylactic cranial irradiation group vs two 2% of 111 in the observation group), malaise (three 3% vs one <1%), and muscle weakness in a lower limb (one <1% vs six 5%). No treatment-related deaths occurred in either group. Interpretation In this Japanese trial, prophylactic cranial irradiation did not result in longer overall survival compared with observation in patients with extensive-disease small-cell lung cancer. Prophylactic cranial irradiation is therefore not essential for patients with extensive-disease small-cell lung cancer with any response to initial chemotherapy and a confirmed absence of brain metastases when patients receive periodic MRI examination during follow-up. Funding The Ministry of Health, Labour and Welfare of Japan.
Immune checkpoint blockade has provided a paradigm shift in cancer therapy, but the success of this approach is very variable; therefore, biomarkers predictive of clinical efficacy are urgently ...required. Here, we show that the frequency of PD-1
CD8
T cells relative to that of PD-1
regulatory T (T
) cells in the tumor microenvironment can predict the clinical efficacy of programmed cell death protein 1 (PD-1) blockade therapies and is superior to other predictors, including PD ligand 1 (PD-L1) expression or tumor mutational burden. PD-1 expression by CD8
T cells and T
cells negatively impacts effector and immunosuppressive functions, respectively. PD-1 blockade induces both recovery of dysfunctional PD-1
CD8
T cells and enhanced PD-1
T
cell-mediated immunosuppression. A profound reactivation of effector PD-1
CD8
T cells rather than PD-1
T
cells by PD-1 blockade is necessary for tumor regression. These findings provide a promising predictive biomarker for PD-1 blockade therapies.
Mesoporous silica nanoparticles (MSNs) are physically and chemically stable inorganic nanomaterials that have been attracting much attention as carriers for drug delivery systems in the field of ...nanomedicine. In the present study, we investigated the potential of MSN vaccines that incorporate antigen peptides for use in cancer immunotherapy. In vitro experiments demonstrated that fluorescently labeled MSNs accumulated in a line of mouse dendritic cells (DC2.4 cells), where the particles localized to the cytosol. These observations could suggest that MSNs have potential for use in delivering the loaded molecules into antigen-presenting cells, thereby stimulating the host acquired immune system. In vivo experiments demonstrated prolonged survival in mice implanted with ovalbumin (OVA)-expressing lymphoma cells (E.G7-OVA cells) following subcutaneous inoculation with MSNs incorporating OVA antigen peptides. Furthermore, OVA-specific immunoglobulin G antibodies and cytotoxic T lymphocytes were detected in the serum and the spleen cells, respectively, of mice inoculated with an MSN-OVA vaccine, indicating the induction of antigen-specific responses in both the humoral and cellular immune systems. These results suggested that the MSN therapies incorporating antigen peptides may serve as novel vaccines for cancer immunotherapy.
Development of lung adenocarcinoma (LADC), the most frequent histological type of lung cancer, depends in many cases on the activation of “driver” oncogenes such as KRAS, epidermal growth factor ...receptor (EGFR), and anaplastic lymphoma kinase (ALK). Inhibitors that target the EGFR and ALK tyrosine kinases show therapeutic effects against LADCs containing EGFR gene mutations and ALK gene fusions, respectively. Recently, we and others identified the RET fusion gene as a new targetable driver gene in LADC. The RET fusions occur in 1–2% of LADCs. Existing US Food and Drug Administration‐approved inhibitors of RET tyrosine kinase show promising therapeutic effects both in vitro and in vivo, as well as in a few patients. Clinical trials are underway to investigate the therapeutic effects of RET tyrosine kinase inhibitors, such as vandetanib (ZD6474) and cabozantinib (XL184), in patients with RET fusion‐positive non‐small‐cell lung cancer.
We launched SCRUM-Japan platform for the cancer genome profiling (CGP) test screening followed by the enrollment to genomically-matched clinical trials in 2015. More than 30,000 tissue-based and ...10,000 liquid-based CGP tests have already been performed for enrolling to a total of 127 industry-/investigator-initiated registration trials, which resulted in regulatory approvals of 12 new agents with 14 indications in Japan. Using the clinical-genomic database, a new driver gene was recently discovered with dramatic response by genomically-matched agent. Our comparative study with tissue-based CGPs revealed more usefulness of liquid biopsy in terms of less invasive manner, shorter turn-round time, and higher enrollment rate for matched treatments than tissue-based in gastrointestinal cancers. For detecting minimal/molecular residual disease (MRD) after surgery, post-surgical monitoring with tumor-informed liquid biopsy assay in association with two randomized control trials have also started in 2020 (CIRCULATE-Japan). The observational cohort study showed obvious efficacy of the MRD monitoring for predicting recurrence, leading to change clinical practice in patient selection who should receive adjuvant therapy in the near future.
Cryoprobe is a novel transbronchial biopsy (TBB) tool that yields larger tissue samples than forceps. Pathological diagnosis and biomarker analysis, such as genetic alterations and programmed ...death‐ligand 1 (PD‐L1) expression, are paramount for precision medicine against lung cancer. We evaluated the safety and usefulness of cryoprobe TBB for lung cancer diagnosis and biomarker analysis. In this single‐center, prospective single‐arm study, patients suspected of having or diagnosed with primary lung cancer underwent cryoprobe TBB using flexible bronchoscopy after conventional forceps TBB from the same lesion. Cryoprobe TBB was performed in 121 patients. The incidence rate of severe bleeding and serious adverse events (4% 90% confidence interval: 2%‐9%) was significantly lower than the expected rate (20% with 30% threshold, P < 0.01). Combining both central and peripheral lesions, the diagnostic yield rate of cryoprobe samples was 76% and that of forceps samples was 84%. Compared with forceps TBB samples, cryoprobe TBB samples were larger (cryoprobe 15 mm2 vs forceps 2 mm2) and resulted in a larger proportion of definite histomorphological diagnosis (cryoprobe 86% vs forceps 74%, P < 0.01), larger amounts of DNA extracted from samples (median: cryoprobe, 1.60 µg vs forceps, 0.58 µg, P = 0.02) and RNA (median: cryoprobe, 0.62 µg vs forceps, 0.17 µg, P < 0.01) extracted from samples, and tended to yield greater rates of PD‐L1 expression >1% (51% vs 42%). In conclusion, cryoprobe is a safe and useful tool for obtaining lung cancer tissue samples of adequate size and quality, which allow morphological diagnosis and biomarker analysis for precision medicine against lung cancer.
In this study, cryoprobe biopsy was performed in 121 patients. The incidence rate of severe bleeding and serious adverse events was 4%. Compared with forceps biopsy samples, cryoprobe biopsy samples were larger and resulted in a larger proportion of definite histomorphological diagnoses and larger amounts of DNA/RNA extracted from samples.
Oncogenic epidermal growth factor receptor (EGFR) signaling plays an important role in regulating global metabolic pathways, including aerobic glycolysis, the pentose phosphate pathway (PPP), and ...pyrimidine biosynthesis. However, the molecular mechanism by which EGFR signaling regulates cancer cell metabolism is still unclear. To elucidate how EGFR signaling is linked to metabolic activity, we investigated the involvement of the RAS/MEK/ERK and PI3K/AKT/mammalian target of rapamycin (mTOR) pathways on metabolic alteration in lung adenocarcinoma (LAD) cell lines with activating EGFR mutations. Although MEK inhibition did not alter lactate production and the extracellular acidification rate, PI3K/mTOR inhibitors significantly suppressed glycolysis in EGFR-mutant LAD cells. Moreover, a comprehensive metabolomics analysis revealed that the levels of glucose 6-phosphate and 6-phosphogluconate as early metabolites in glycolysis and PPP were decreased after inhibition of the PI3K/AKT/mTOR pathway, suggesting a link between PI3K signaling and the proper function of glucose transporters or hexokinases in glycolysis. Indeed, PI3K/mTOR inhibition effectively suppressed membrane localization of facilitative glucose transporter 1 (GLUT1), which, instead, accumulated in the cytoplasm. Finally, aerobic glycolysis and cell proliferation were down-regulated when GLUT1 gene expression was suppressed by RNAi. Taken together, these results suggest that PI3K/AKT/mTOR signaling is indispensable for the regulation of aerobic glycolysis in EGFR-mutated LAD cells.
Background: EGFR signaling maintains aerobic glycolysis, but the molecular mechanism is still undefined.
Results: Drug inhibition studies reveal that downstream signaling via the PI3K pathway is critical for glucose transport and metabolism.
Conclusion: The PI3K signaling regulates key metabolic activities in EGFR-mutant lung adenocarcinoma.
Significance: These data may guide the development of chemotherapeutic options, including targeting of the PI3K pathway and glucose transporter machinery.
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