Epidermal growth factor receptor tyrosine kinase inhibitors for the treatment of central nervous system metastases from non-small cell lung cancer: the present and the future

A Review of the Molecular Determinants of Therapeutic Response in Non-Small Cell Lung Cancer Brain Metastases

Lung cancer is a leading cause of cancer-related morbidity and mortality worldwide. Metastases in the brain are a common hallmark of advanced stages of the disease, contributing to a dismal prognosis. Lung cancer can be broadly classified as either small cell lung cancer (SCLC) or non-small cell lung cancer (NSCLC). NSCLC represents the most predominant histology subtype of lung cancer, accounting for the majority of lung cancer cases. Recent advances in molecular genetics, coupled with innovations in small molecule drug discovery strategies, have facilitated both the molecular classification and precision targeting of NSCLC based on oncogenic driver mutations. Furthermore, these precision-based strategies have demonstrable efficacy across the blood-brain barrier, leading to positive outcomes in patients with brain metastases. This review provides an overview of the clinical features of lung cancer brain metastases, as well as the molecular mechanisms that drive NSCLC oncogenesis. We also explore how precision medicine-based strategies can be leveraged to improve NSCLC brain metastases.

Proteomic profile of Trichinella spiralis infected mice with acute spinal cord injury: A 4D label-free quantitative analysis

Spinal cord injury (SCI) can cause severe loss of locomotor and sensory activities, with no ideal treatment. Emerging reports suggest that the helminth therapy is highly effective in relieving numerous inflammatory diseases. Proteomic profiling is often used to elucidate the underlying mechanism behind SCI. Herein, we systematically compared the protein expression profiles of murine SCI spinal cord and Trichinella spiralis treated murine SCI spinal cord, using a 4D label-free technique known for its elevated sensitivity. Relative to the SCI mice, the T. spiralis-treated mice exhibited marked alterations in 91 proteins (31 up- and 60 down-regulated). Based on our Gene Ontology (GO) functional analysis, the differentially expressed proteins (DEPs) were primarily enriched in the processes of metabolism, biological regulation, cellular process, antioxidant activity, and other cell functions. In addition, according to the Clusters of Orthologous Groups of protein/EuKaryotic Orthologous Groups (COG/KOG) functional stratification, proteins involved in signaling transduction mechanisms belonged to the largest category. Over-expressed DEPs were also enriched in the "NADPH oxidase complex", "superoxide anion generation", "other types of O-glycan biosynthesis", and "HIF-1 signaling pathway". Furthermore, the protein-protein interaction (PPI) network identified the leading 10 hub proteins. In conclusion, we highlighted the dynamic proteomic profiling of T. spiralis-treated SCI mice. Our findings provide significant insight into the molecular mechanism behind T. spiralis regulation of SCI.

LINC01140 inhibits nonsmall cell lung cancer progression and cisplatin resistance through the miR-4742-5p/TACC1 axis

Recent studies show that lncRNAs participate in drug resistance and nonsmall cell lung cancer (NSCLC) progression. This study aimed to study the roles and mechanisms of long intergenic nonprotein coding RNA 01140 (LINC01140) in regulating NSCLC progression and drug resistance. Real-time quantitative polymerase chain reaction and western blot analysis were used to detect LINC01140, miR-4742-5p, and transforming acidic coiled-coil 1 (TACC1) expression in NSCLC cells. The interaction between two molecules was examined by luciferase reporter and/or RNA immunoprecipitation assays. Cell invasion, apoptosis, and cisplatin cytotoxicity were assessed by transwell invasion assay, flow cytometry analysis, and CCK-8 assay, respectively. LINC01140 was downregulated and miR-4742-5p was upregulated in NSCLC. LINC01140 inhibited miR-4742-5p expression by competitively binding to miR-4742-5p, while miR-4742-5p targeted TACC1 to inhibit TACC1 expression in NSCLC cells. LINC01140 enrichment repressed the invasive potential and cisplatin resistance and triggered apoptosis, which was reversed by miR-4742-5p overexpression. miR-4742-5p inhibition suppressed cell invasion and cisplatin resistance and accelerated apoptosis in NSCLC cells, while TACC1 silencing abolished these effects. Mechanistically, LINC01140 positively regulated TACC1 expression by sponging miR-4742-5p. In conclusion, LINC01140 inhibited NSCLC progression and cisplatin resistance via functioning as a ceRNA for miR-4742-5p to modulate TACC1.

Efficacy and Prognosis of First-Line EGFR-Tyrosine Kinase Inhibitor Treatment in Older Adults Including Poor Performance Status Patients with EGFR-Mutated Non-Small-Cell Lung Cancer

Introduction

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are standard first-line treatments for advanced EGFR-mutated non-small-cell lung cancer (NSCLC) patients. The efficacy of EGFR-TKIs in older patients including poor Eastern Cooperative Oncology Group (ECOG) performance status (PS) is seldom investigated.

Methods

We enrolled patients 65 years or older with EGFR-mutated Stage IIIB-IV NSCLC and evaluated the efficacy and prognosis of first-line EGFR-TKI treatment. Clinical and demographic characteristics were reviewed and analyzed, including age, sex, PS, smoking history, EGFR mutation type, treatment regimen, progression-free survival (PFS), and overall survival (OS).

Results

From January 2015 to December 2019, a total of 237 patients were included, 205 of whom were eligible for efficacy and outcome analyses. Among them, 91 (44.4%) were categorized as poor PS (2-4). Compared with patients categorized as good PS (0-1), those with poor PS were older (79 versus 75 years), had a higher proportion of brain metastases (41.8% versus 25.4%), more comorbidities (74.7% versus 54.4%), and more likely to be treated with first-generation TKIs (74.7% versus 57.0%). The PFS and OS were 17.1 and 26.7 months respectively in patients with good PS and 12.7 and 18.2 months in those with poor PS (both p < 0.001). In the multivariate analysis, good PS, <3 metastatic sites, and first-line treatment with afatinib compared with erlotinib and gefitinib were associated with longer PFS. A relatively younger age, good PS, < 3 metastatic sites, and no brain metastasis at diagnosis were associated with better OS.

Conclusion

In older patients with EGFR-mutated NSCLC and receive EGFR-TKI treatment, a good PS and <3 metastatic sites at diagnosis were associated with a longer PFS and OS. In addition, afatinib as first-line treatment was associated with a longer PFS whereas a relatively younger age and no brain metastasis at diagnosis were associated with better OS.

Blocking the EGFR/p38/NF-κB signaling pathway alleviates disruption of BSCB and subsequent inflammation after spinal cord injury

Epidermal growth factor receptor (EGFR) activation is involved in blood spinal cord barrier (BSCB) disruption and secondary injury after spinal cord injury (SCI). However, the underlying mechanisms of EGFR activation mediating BSCB disruption and secondary injury after SCI remain unclear. An in vitro model of oxygen and glucose deprivation/reoxygenation (OGD/R) induced BSCB damage and in vivo rat SCI model were employed to define the role of EGFR/p38/NF-κB signal pathway activation and its induced inflammatory injury in main cellular components of BSCB. Genetic regulation (lentivirus delivered shRNA and overexpression system) or chemical intervention (agonist or inhibitor) were applied to activate or inactivate EGFR and p38 in astrocytes and microvascular endothelial cells (MEC) under which conditions, the expression of pro-inflammatory factors (TNF-α, iNOS, COX-2, and IL-1β), tight junction (TJ) protein (ZO-1 and occludin), nuclear translocation of NF-κB and permeability of BSCB were analyzed. The pEGFR was increased in astrocytes and MEC which induced the activation of EGFR and p38 and NF-κB nuclear translocation. The activation of EGFR and p38 increased the TNF-α, iNOS, COX-2, and IL-1β responsible for the inflammatory injury and reduced the ZO-1 and occludin which caused BSCB disruption. While EGFR or p38 inactivation inhibited NF-κB nuclear translocation, and markedly attenuated the production of pro-inflammatory factors and the loss of TJ protein. This study suggests that the EGFR activation in main cellular components of BSCB after SCI mediates BSCB disruption and secondary inflammatory injury via the EGFR/p38/NF-κB pathway.

Whole-brain radiotherapy with and without concurrent erlotinib in NSCLC with brain metastases: a multicenter, open-label, randomized, controlled phase III trial

BACKGROUND

Erlotinib combined with whole-brain radiotherapy (WBRT) demonstrated a favorable objective response rate in a phase II single-arm trial of non-small cell lung cancer (NSCLC) patients with brain metastases. We assessed whether concurrent erlotinib with WBRT is safe and benefits patients in a phase III, randomized trial.

METHODS

NSCLC patients with two or more brain metastases were enrolled and randomly assigned (1:1) to WBRT (n = 115) or WBRT combined with erlotinib arms (n = 109). The primary endpoint was intracranial progression-free survival (iPFS) and cognitive function (CF) was assessed by the Mini-Mental State Examination (MMSE).

RESULTS

A total of 224 patients from 10 centers across China were randomized to treatments. Median follow-up was 11.2 months. Median iPFS for WBRT concurrent erlotinib was 11.2 months vs 9.2 months for WBRT-alone (P = .601). Median PFS and overall survival (OS) of combination group were 5.3 vs 4.0 months (P = .825) and 12.9 vs 10.0 months (P = .545), respectively, compared with WBRT-alone. In EGFR-mutant patients, iPFS (14.6 vs 12.8 months; P = .164), PFS (8.8 vs 6.4 months; P = .702), and OS (17.5 vs 16.9 months; P = .221) were not significantly improved in combination group over WBRT-alone. Moreover, there were no significant differences in patients experiencing MMSE score change between the treatments.

CONCLUSION

Concurrent erlotinib with WBRT didn't improve iPFS and excessive CF detriment either in the intent-to-treat (ITT) population or in EGFR-mutant patients compared with WBRT-alone, suggesting that while safe for patients already taking the drug, there is no justification for adding concurrent EGFR-TKI with WBRT for the treatment of brain metastases. Trial registration: Clinical trials.gov identifier: NCT01887795.

Single-Cell Characterization of the Immune Microenvironment of Melanoma Brain and Leptomeningeal Metastases

PURPOSE

Melanoma brain metastases (MBM) and leptomeningeal melanoma metastases (LMM) are two different manifestations of melanoma CNS metastasis. Here, we used single-cell RNA sequencing (scRNA-seq) to define the immune landscape of MBM, LMM, and melanoma skin metastases.

EXPERIMENTAL DESIGN

scRNA-seq was undertaken on 43 patient specimens, including 8 skin metastases, 14 MBM, and 19 serial LMM specimens. Detailed cell type curation was performed, the immune landscapes were mapped, and key results were validated by IHC and flow cytometry. Association analyses were undertaken to identify immune cell subsets correlated with overall survival.

RESULTS

The LMM microenvironment was characterized by an immune-suppressed T-cell landscape distinct from that of brain and skin metastases. An LMM patient with long-term survival demonstrated an immune repertoire distinct from that of poor survivors and more similar to normal cerebrospinal fluid (CSF). Upon response to PD-1 therapy, this extreme responder showed increased levels of T cells and dendritic cells in their CSF, whereas poor survivors showed little improvement in their T-cell responses. In MBM patients, therapy led to increased immune infiltrate, with similar T-cell transcriptional diversity noted between skin metastases and MBM. A correlation analysis across the entire immune landscape identified the presence of a rare population of dendritic cells (DC3) that was associated with increased overall survival and positively regulated the immune environment through modulation of activated T cells and MHC expression.

CONCLUSIONS

Our study provides the first atlas of two distinct sites of melanoma CNS metastases and defines the immune cell landscape that underlies the biology of this devastating disease.

Challenges and Novel Opportunities of Radiation Therapy for Brain Metastases in Non-Small Cell Lung Cancer

Simple Summary

Lung cancer is the most common primary malignancy that tends to metastasize to the brain. Owing to improved survival of lung cancer patients, the prevalence of brain metastases is a matter of growing concern. Brain radiotherapy remains the mainstay in the management of metastatic CNS disease. However, new targeted therapies such as the tyrosine kinase or immune checkpoint inhibitors have demonstrated intracranial activity and promising tumor response rates. Here, we review the current and emerging therapeutical strategies for brain metastases from non-small cell lung cancer, both brain-directed and systemic, as well as the uncertainties that may arise from their combination.

Abstract

Approximately 20% patients with non-small cell lung cancer (NSCLC) present with CNS spread at the time of diagnosis and 25–50% are found to have brain metastases (BMs) during the course of the disease. The improvement in the diagnostic tools and screening, as well as the use of new systemic therapies have contributed to a more precise diagnosis and prolonged survival of lung cancer patients with more time for BMs development. In the past, most of the systemic therapies failed intracranially because of the inability to effectively cross the blood brain barrier. Some of the new targeted therapies, especially the group of tyrosine kinase inhibitors (TKIs) have shown durable CNS response. However, the use of ionizing radiation remains vital in the management of metastatic brain disease. Although a decrease in CNS-related deaths has been achieved over the past decade, many challenges arise from the need of multiple and repeated brain radiation treatments, which carry along not insignificant risks and toxicity. The combination of stereotactic radiotherapy and systemic treatments in terms of effectiveness and adverse effects, such as radionecrosis, remains a subject of ongoing investigation. This review discusses the challenges of the use of radiation therapy in NSCLC BMs in view of different systemic treatments such as chemotherapy, TKIs and immunotherapy. It also outlines the future perspectives and strategies for personalized BMs management.

Metachronous Brain Metastasis in patients with EGFR-mutant NSCLC indicates a worse prognosis

Purpose: NSCLC patients with EGFR mutation were associated with high incidence of brain metastasis (BM). BM could be grouped by the time of occurrence, including synchronous BM at initial diagnosis and metachronous BM during disease course. The primary aim of the study was to investigate the survival of patients with metachronous BM.

Methods: A total of 99 EGFR-mutant advanced NSCLC patients in our institute between 2012 and 2018 were grouped into synchronous BM and metachronous BM. Comparisons of OS were performed based on BM status. The independent prognostic factors of OS were investigated, and extracranial and intracranial PFS were further analyzed.

Results: Patients with metachronous BM (mOS: 22.1 months) had poorer outcomes than synchronous BM (mOS: 30.3 months) (P=0.016). Moreover, multivariate analysis indicated that BM status (P=0.015), local therapy for BM (P=0.013) and subsequent treatment of Osimertinib (P=0.008) impact significantly on OS. Significantly, the proportion of local therapy for BM had no difference between patients with synchronous and metachronous BM. And patients with metachronous BM harbored a more favorable prognostic factor (higher proportion of subsequent Osimertinib treatment), but also harbored a poorer prognostic factor (metachronous BM), which confirmed BM status was the most significant prognostic factor of OS. At last, results of extracranial and intracranial PFS indicated that patients with metachronous BM tended to have a higher risk of intracranial disease progression.

Conclusions: Patients developing metachronous BM during EGFR-TKIs treatment have worse outcomes than synchronous BM. Our findings suggested that the patients with metachronous BM should receive more aggressive treatments.

Rociletinib (CO-1686) enhanced the efficacy of chemotherapeutic agents in ABCG2-overexpressing cancer cells in vitro and in vivo

Overexpression of adenosine triphosphate (ATP)-binding cassette subfamily G member 2 (ABCG2) in cancer cells is known to cause multidrug resistance (MDR), which severely limits the clinical efficacy of chemotherapy. Currently, there is no FDA-approved MDR modulator for clinical use. In this study, rociletinib (CO-1686), a mutant-selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), was found to significantly improve the efficacy of ABCG2 substrate chemotherapeutic agents in the transporter-overexpressing cancer cells in vitro and in MDR tumor xenografts in nude mice, without incurring additional toxicity. Mechanistic studies revealed that in ABCG2-overexpressing cancer cells, rociletinib inhibited ABCG2-mediated drug efflux and increased intracellular accumulation of ABCG2 probe substrates. Moreover, rociletinib, inhibited the ATPase activity, and competed with [¹²⁵I] iodoarylazidoprazosin (IAAP) photolabeling of ABCG2. However, ABCG2 expression at mRNA and protein levels was not altered in the ABCG2-overexpressing cells after treatment with rociletinib. In addition, rociletinib did not inhibit EGFR downstream signaling and phosphorylation of protein kinase B (AKT) and extracellular signal-regulated kinase (ERK). Our results collectively showed that rociletinib reversed ABCG2-mediated MDR by inhibiting ABCG2 efflux function, thus increasing the cellular accumulation of the transporter substrate anticancer drugs. The findings advocated the combination use of rociletinib and other chemotherapeutic drugs in cancer patients with ABCG2-overexpressing MDR tumors.

Tyrosine Kinase Inhibitor Therapy for Brain Metastases in Non-Small-Cell Lung Cancer: A Primer for Radiologists

Treatment options for patients who develop brain metastases secondary to non-small-cell lung cancer have rapidly expanded in recent years. As a key adjunct to surgical and radiation therapy options, systemic therapies are now a critical component of the oncologic management of metastatic CNS disease in many patients with non-small-cell lung cancer. The aim of this review article was to provide a guide for radiologists, outlining the role of systemic therapies in metastatic non-small-cell lung cancer, with a focus on tyrosine kinase inhibitors. The critical role of the blood-brain barrier in the development of systemic therapies will be described. The final sections of this review will provide an overview of current imaging-based guidelines for therapy response. The utility of the Response Assessment in Neuro-Oncology criteria will be discussed, with a focus on how to use the response criteria in the assessment of patients treated with systemic and traditional therapies.

Hsa-miR-217 Inhibits the Proliferation, Migration, and Invasion in Non-small Cell Lung Cancer Cells Via Targeting SIRT1 and P53/KAI1 Signaling

Background:

Brain metastasis is a major cause of cancer death in patients with lung cancer. Sirtuin 1 and hsa-miR-217 have been identified to mediate the development of non-small cell lung cancer.

Aims:

To investigate the roles of hsa-miR-217, its target sirtuin 1, and the P53/KAI1 axis in the brain metastasis from non-small cell lung cancer.

Study Design:

Cell culture study.

Methods:

Human pulmonary adenocarcinoma brain metastasis cell line PC-14/B were incubated and treated with constructed lentiviral plasmids expressing miR-217 and/or sirtuin 1. BEAS-2B cell line was used as a control. The targeted regulation of miR-217 to sirtuin 1was examined using a dual-luciferase reporter assay. Cell proliferation, migration, invasion, and related protein expression were detected to examine the effect of the miR-217/sirtuin 1 expression on metastasis.

Results:

PC-14/B cells expressed higher sirtuin 1 and lower P53 and KAI1 compared with BEAS-2B control cells (p<0.05). Sirtuin 1 was a direct target of miR-217. MiR-217 expression suppressed PC-14/B cell invasion (p=0.004), migration (p=0.001), and proliferation (p<0.05), whereas sirtuin 1 overexpression reversed all processes. sirtuin 1 expression inhibited P53, KAI1/CD82, matrix metalloproteinase-9, and β-catenin but upregulated E-cadherin protein. MiR-217 overexpression induced reverse changes.

Conclusion:

Hsa-miR-217 and its target sirtuin 1 acted as metastasis suppressor and promoter gene in non-small cell lung cancer, respectively. The hsa-miR-217/sirtuin 1/P53/KAI1 metastasis regulatory pathway showed novel and crucial roles in brain metastasis from non-small cell lung cancer. This axis might be a potential target for the treatment of brain metastasis of lung cancer.

Complete Remission of Multiple Brain Metastases in a Patient with EGFR-Mutated Non-Small-Cell Lung Cancer Treated with First-Line Osimertinib without Radiotherapy

Osimertinib has demonstrated efficacy against stable or asymptomatic central nervous system (CNS) metastases of epidermal growth factor receptor (EGFR) mutation-positive non-small-cell lung cancer (NSCLC) in phase 2 and 3 clinical trials that allowed prior CNS radiotherapy. However, the efficacy of osimertinib only or the optimal treatment combination or sequence of radiotherapy has not been investigated. A 74-year-old woman diagnosed with T4N1M1c Stage IVB lung adenocarcinoma with EGFR mutation presented with a left upper lobe mass and multiple bilateral lung metastases. A total of more than 20 asymptomatic multiple brain metastases with a maximum diameter of 12 mm were diagnosed simultaneously. Osimertinib was administered as first-line treatment. Whole brain radiotherapy was deferred because she had no neurological symptoms. After 5 weeks, the multiple brain metastases disappeared completely, together with the response in the lung lesions. This case demonstrated that first-line treatment with osimertinib could even achieve complete remission of multiple brain metastases comprising as many as twenty lesions of EGFR-mutated NSCLC without radiation therapy. Radiation therapy for brain metastases can be deferred or even withheld. A new treatment strategy for EGFR mutated NSCLC with CNS metastases should be investigated using osimertinib, especially regarding optimal combination or sequence of radiotherapy.

Four generations of EGFR TKIs associated with different pathogenic mutations in non-small cell lung carcinoma

Non-small cell lung carcinoma (NSCLC) is a malignant tumour with poor prognosis and high mortality. Platinum-based dual-agent chemotherapy is the main therapeutic regimen for this disease. In recent years, because of the introduction of molecular targeted therapy, various targeted therapeutic agents against epidermal growth factor receptor (EGFR) have been rapidly developed, which has become a research hotspot for NSCLC treatment. Here, we review the latest studies describing the features and types of EGFR pathogenic mutations, currently established EGFR-tyrosine kinase inhibitors from the first to fourth generation, including their action mechanisms, acquired resistance, and clinical applications, and potential challenges and perspectives that current researchers should address.

The Effect of Epidermal Growth Factor Receptor Mutation on Intracranial Progression-Free Survival of Non-Small Cell Lung Cancer Patients with Brain Metastasis Underwent Gamma Knife Radiosurgery

BACKGROUND

The aim of this study was to survey prognostic factors, particularly those focusing on epidermal growth factor receptor (EGFR) mutations, of patients with non-small cell lung cancer (NSCLC) after Gamma Knife Radiosurgery (GKRS) for metastatic brain tumors.

METHODS

We retrospectively reviewed the medical records of 98 patients with NSCLC who underwent GKRS for brain metastases from August 2010 to July 2017. The primary endpoint was progression-free survival (PFS) of the intracranial disease. We analyzed variables such as age, sex, Karnofsky Performance Status, recursive partitioning analysis (RPA) class, smoking status, primary cancer pathology, EGFR mutations, and time to brain metastases as prognostic factors.

RESULTS

The median overall survival (OS) of the patients was 16 months [95% confidence interval (CI), 13-21 months]. Median systemic PFS and intracranial PFS were 9 months (95% CI, 8-11 months) and 11 months (95% CI, 7-14 months), respectively. Kaplan-Meier survival analysis revealed that the patients with EGFR mutations had longer intracranial PFS than those without EGFR mutation (median intracranial PFS: 19 vs. 10 months with p=0.01) while they had no benefits in OS and systemic PFS. Furthermore, the patients harboring adenocarcinoma had longer OS (p<0.01) and intracranial PFS (p<0.01) and the patients with lower RPA class had longer OS (p=0.02) and intracranial PFS (p=0.03).

CONCLUSION

EGFR mutations, primary cancer pathology, and RPA class may be proposed as prognostic factors for intracranial PFS in NSCLC patients after GKRS for brain metastasis in this study.

Apurinic endonuclease 1 promotes the cisplatin resistance of lung cancer cells by inducing Parkin‑mediated mitophagy

Platinum-containing doublet chemotherapy is the cornerstone of lung cancer treatment; however, cisplatin resistance is a major obstacle in the treatment of lung cancer. However, the mechanism underlying this resistance has not been fully elucidated. Previous studies have shown that serum apurinic/apyrimidinic endonuclease 1 (APE1) levels in patients with NSCLC are inversely associated with progression-free survival after platinum-containing doublet chemotherapy, and can serve as a biomarker for predicting disease prognosis and treatment efficacy. The present study was designed to investigate the role played by APE1 in the resistance of lung cancer to cisplatin. The levels of mitochondrial apurinic endonuclease 1 (m-APE1) and total APE1 (t-APE1) protein in a cisplatin-resistant A549 cell line (A549/DDP) and cisplatin-sensitive A549 cells were analyzed by western blotting. Mitochondrial membrane potential was detected by using the JC-1 staining method. The cisplatin-resistance of APE1-overexpressing A549 cells and APE1-silenced A549/DDP cells was assessed by cell apoptosis and colony formation assays. The results revealed that cisplatin-resistant A549 cells contained high levels of APE1, and exhibited elevated levels of autophagy. The levels of m-APE1 and t-APE1 protein were increased in the A549/DDP cells when compared with these levels in the A549 cells. Overexpression of APE1 and Mia40 enhanced the cisplatin resistance and autophagy of the A549 cells. APE1 knockdown restored the cisplatin sensitivity and reduced the levels of LC3II and Parkin in the A549/DDP cells, but promoted the release of cytochrome c. Furthermore, Parkin silencing or treatment with 3-methyladenine (3-MA, an autophagy inhibitor) promoted the apoptosis of APE1-overexpressing A549 cells, indicating that Parkin-mediated mitophagy plays an important role in the APE1-induced cisplatin resistance of A549 cells. In conclusion, APE1 promotes the cisplatin resistance of lung cancer cells by inducing Parkin-mediated mitophagy.

Effectiveness and safety of osimertinib in patients with metastatic EGFR T790M-positive NSCLC: An observational real-world study

Osimertinib showed encouraging efficacy in patients with advanced EGFR T790M-positive NSCLC in previous randomized controlled trials. This real-world study aimed to evaluate the effectiveness and safety of osimertinib in a real-world setting. This observational study (NCT03133234) included 74 patients with metastatic EGFR T790M-positive NSCLC who progressed on prior EGFR TKI therapy and received osimertinib between May 2016 and April 2018 at the Kiang Wu Hospital in Macau. Response rate (RR) and other endpoints (progression-free survival [PFS], overall survival [OS], disease control rate [DCR], stable disease rate, and adverse events) were assessed. Survival data were estimated using the Kaplan-Meier method. All patients had stage IV lung adenocarcinoma and 25.6% had brain metastases; median age was 58 years (range 28-84 years) and 83.8% of patients had received at least three prior lines of treatment. The median duration of osimertinib treatment was 8 months (range, 1-25 months). RR and DCR were 67.5% (95% CI 56.9-78.1) and 79.8% (95% CI 70.7-88.9), respectively, while 12.1% had stable disease. The median PFS was 9.0 months (95% CI 6.7-11.2 months), and the median OS was 12.0 months (95% CI 8.8-15.1 months). Nausea (25.8%) and decreased appetite (20.2%) were the most common adverse events associated with osimertinib treatment. Even though most patients had at least three lines of prior treatment, real-world RR and PFS with osimertinib in this study were consistent with those from randomized controlled trials; no new safety signals were observed.

Multidisciplinary expert opinion on the treatment consensus for patients with EGFR mutated NSCLC with brain metastases

The presence of an epidermal growth factor receptor (EGFR) mutation is associated with higher incidence of brain metastases in patients with non-small cell lung cancer (NSCLC); however, patients with synchronous brain metastases at diagnosis have generally been excluded from clinical trials. As there is limited clinical evidence for managing this patient population, a multidisciplinary group of Spanish medical and radiation oncologists, and neuro-oncologist with expertise treating brain metastases in lung cancer patients met with the aim of reaching and developing an expert opinion consensus on the management of patients with EGFR mutated NSCLC with brain metastases. This consensus contains 26 recommendations and 20 conclusion statements across 21 questions in 7 areas, as well as a first-line treatment algorithm.

Relationship between EGFR mutation and computed tomography characteristics of the lung in patients with lung adenocarcinoma

Background

The aim of this study was to investigate the relationship between EGFR mutation and computed tomography (CT) features in patients with adenocarcinoma of the lung.

Methods

One hundred and ninety two lung adenocarcinoma patients who underwent surgery were retrospectively included in this study. Examination of EGFR gene mutation was performed on all resected tumor samples. The 192 recruited lung adenocarcinoma patients were divided into groups according to EGFR mutation status: patients with mutations in exons 18–21 (effective mutated, n = 61) and non‐mutated (n = 131). The clinical characteristics and lung CT imaging features of the two groups were recorded and compared. Univariate and logistic regression analysis were performed to identify the independent risk factors relevant to effective EGFR gene mutation.

Results

The independent risk factors relevant to effective EGFR mutation were evaluated by logistic regression test. The results indicated that female gender (odds ratio [OR] 3.23), lung CT features of lymphangitis carcinomatosa (OR 2.66), semi‐solid lesion density (OR 3.56), and spicule sign (OR 1.61) were independent risk factors relevant to EGFR mutation.

Conclusion

Female patients with lung CT features of lymphangitis carcinomatosa, semi‐solid lesion density, and spicule sign are more prone to harbor EGFR gene mutations and are more likely to benefit from targeted therapy.

The biology and therapeutic management of melanoma brain metastases

The recent years have seen significant progress in the development of systemic therapies to treat patients with advanced melanoma. Use of these new treatment modalities, which include immune checkpoint inhibitors and small molecule BRAF inhibitors, lead to increased overall survival and better outcomes. Although revolutionary, these therapies are often less effective against melanoma brain metastases, and frequently the CNS is the major site of treatment failure. The development of brain metastases remains a serious complication of advanced melanoma that is associated with significant morbidity and mortality. New approaches to both prevent the development of brain metastases and treat established disease are urgently needed. In this review we will outline the mechanisms underlying the development of melanoma brain metastases and will discuss how new insights into metastasis biology are driving the development of new therapeutic strategies. Finally, we will describe the latest data from the ongoing clinical trials for patients with melanoma brain metastases.

Osimertinib in the treatment of non-small-cell lung cancer: design, development and place in therapy

The discovery of epidermal growth factor receptor (EGFR) mutations and subsequent demonstration of the efficacy of genotype-directed therapies with EGFR tyrosine kinase inhibitors (TKIs) marked the advent of the era of precision medicine for non-small-cell lung cancer (NSCLC). First- and second-generation EGFR TKIs, including erlotinib, gefitinib and afatinib, have consistently shown superior efficacy and better toxicity compared with first-line platinum-based chemotherapy and currently represent the standard of care for EGFR-mutated advanced NSCLC patients. However, tumors invariably develop acquired resistance to EGFR TKIs, thereby limiting the long-term efficacy of these agents. The T790M mutation in exon 20 of the EGFR gene has been identified as the most common mechanism of acquired resistance. Osimertinib is a third-generation TKI designed to target both EGFR TKI-sensitizing mutations and T790M, while sparing wild-type EGFR. Based on its pronounced clinical activity and good safety profile demonstrated in early Phase I and II trials, osimertinib received first approval in 2015 by the US FDA and in early 2016 by European Medicines Agency for the treatment of EGFR T790M mutation-positive NSCLC patients in progression after EGFR TKI therapy. Recent results from the Phase III AURA3 trial demonstrated the superiority of osimertinib over standard platinum-based doublet chemotherapy for treatment of patients with advanced EGFR T790M mutation-positive NSCLC with disease progression following first-line EGFR TKI therapy, thus definitively establishing this third-generation TKI as the standard of care in this setting. Herein, we review preclinical findings and clinical data from Phase I–III trials of osimertinib, including its efficacy in patients with central nervous system metastases. We further discuss currently available methods used to analyze T790M mutation status and the main mechanisms of resistance to osimertinib. Finally, we provide an outlook on ongoing trials with osimertinib and novel therapeutic combinations that might continue to improve the clinical outcome of EGFR-mutated NSCLC patients.

CLDN1 Increases Drug Resistance of Non-Small Cell Lung Cancer by Activating Autophagy via Up-Regulation of ULK1 Phosphorylation

BACKGROUND The aim of this study was to investigate the expression of CLDN1 in non-small cell lung cancer (NSCLC) and its mechanism of action in cisplatin resistance. MATERIAL AND METHODS A total of 55 patients with NSCLC admitted to our hospital between October 2013 and October 2015 were included. NSCLC tissues and tumor-adjacent tissues (≥5 cm from tumor edge) were collected. Among the 55 patients, 37 had adenocarcinoma and 18 had squamous cell carcinoma. Quantitative real-time polymerase chain reaction was used to determine mRNA expression, and protein expression was examined using Western blotting. CCK-8 assay was used to determine cell proliferation and Transwell assay was used to detect migration and invasion of the cells. Confocal microscopy was used to observe autophagosomes. RESULTS Increased CLDN1 expression promoted the development and metastasis of NSCLC. CLDN1 expression in A549/CDDP cells was up-regulated at both transcriptional and translational levels. Reduced CLDN1 expression decreased the drug resistance, proliferation, migration, and invasion abilities of A549/CDDP cells. Decreased CLDN1 expression promoted the apoptosis of A549/CDDP cells. CLDN1 enhanced CDDP drug resistance of A549 cells by activating autophagy. CLDN1 promoted the autophagy of A549 cells by up-regulating the phosphorylation level of ULK1. CONCLUSIONS The present study demonstrates that expression of CLDN1 in NSCLC is up-regulated and it is correlated with clinicopathological features. CLDN1 activates autophagy through up-regulation of ULK1 phosphorylation and promotes drug resistance of NSCLC cells to CDDP.

Concomitant EML4-ALK rearrangement and EGFR mutation in non-small cell lung cancer patients: a literature review of 100 cases

The discovery of EGFR mutations and EML4-ALK gene rearrangements has radically changed the therapeutic scenario for patients with advanced non-small cell lung cancer. ALK and EGFR tyrosine-kinase inhibitors showed better activity and efficacy than standard chemotherapy in the first and second line treatment settings, leading to a clear advantage in overall survival of advanced non-small cell lung cancer patients harboring these genetic alterations.

Historically the coexistence of EGFR mutations and EML4-ALK rearrangements in the same tumor has been described as virtually impossible. Nevertheless many recent observations seem to show that it is not true in all cases.

In this review we will discuss the available literature data regarding this rare group of patients in order to give some suggestions useful for their clinical management. Furthermore we report here two cases of concomitant presence of both alterations that will help us in the development of discussion.

Treatment in EGFR-mutated Non-small Cell Lung Cancer: How to Block the Receptor and overcome Resistance Mechanisms

In non-small cell lung cancer (NSCLC), the identification of epidermal growth factor receptor (EGFR) mutations and the parallel development of EGFR tyrosine kinase inhibitors (TKIs) have radically changed the therapeutic management strategies. Currently, erlotinib, gefitinib, and afatinib are all approved as standard first-line treatment in EGFR-mutated NSCLC. However, despite the proven efficacy, some EGFR-mutated NSCLCs do not respond to EGFR TKIs, while some patients, after a favorable and prolonged response to EGFR TKIs, inevitably progress within about 10-14 months. Epidermal growth factor receptor-dependent mechanisms, activation of alternative pathways, or phenotypic transformation can cause the resistance to EGFR TKIs. The exon 20 p.Thr790Met point mutation (T790M) is responsible for about 60% of cases of resistance when progression occurs. A third-generation TKI, osimertinib, improved outcome in patients harboring T790M after first- and second-generation TKI treatment. However, resistance develops even after treatment with third-generation drugs. To date, the Cys797Ser (C797S) mutation in exon 20 of EGFR is the most well-known resistance mutation after osimertinib. Fourth-generation TKIs are already under development. Nevertheless, additional information is needed to better understand and effectively overcome resistance. The aim of this review is to report recent advances and future perspectives in the treatment of EGFR-mutated NSCLC, highlighting the resistance mechanisms that underlie disease progression.