Primary resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in patients with non-small-cell lung cancer harboring TKI-sensitive EGFR mutations: an exploratory study

Remarkable response to third-generation EGFR-TKI plus crizotinib in a patient with pulmonary adenocarcinoma harboring EGFR and ROS1 co-mutation: a case report

Background

Driver oncogene mutations, such as c-ros oncogene 1 (ROS1) and epidermal growth factor receptor (EGFR) were previously believed to be mutually exclusive in non-small cell lung cancer (NSCLC). Only sporadic cases of ROS1 and EGFR co-mutations have been reported. Hence, appropriate treatment options for these patients are still controversial.

Case presentation

A 48-year-old female patient presented at our hospital complaining of a persistent cough that had been ongoing for a month. A chest computed tomography showed a mass in the left lung along with hilar and mediastinal lymphadenopathy. Pathological analysis of bronchoscopic biopsy and lung mass puncture confirmed the presence of lung adenocarcinoma. The patient was diagnosed with stage IIIC left lung adenocarcinoma with a clinical stage of cT2N3M0. Next-generation sequencing analysis conducted at both puncture sites revealed an EFGR 19 deletion mutation combined with ROS1 rearrangement. The lung mass exhibited a higher mutation abundance. Treatment with a combination of third-generation EGFR tyrosine kinase inhibitors (TKIs) and crizotinib yielded satisfactory results. During the follow-up period, the mass significantly reduced and almost disappeared.

Conclusion

The co-mutation of EGFR and ROS1 is a rare phenomenon. Nevertheless, the combination of EGFR-TKI and crizotinib treatment appears to hold promise in providing positive results for patients, with manageable side effects. This therapeutic approach has the potential to enhance patients' overall prognosis.

Treatment of advanced non-small cell lung cancer with driver mutations: current applications and future directions

With the improved understanding of driver mutations in non-small cell lung cancer (NSCLC), expanding the targeted therapeutic options improved the survival and safety. However, responses to these agents are commonly temporary and incomplete. Moreover, even patients with the same oncogenic driver gene can respond diversely to the same agent. Furthermore, the therapeutic role of immune-checkpoint inhibitors (ICIs) in oncogene-driven NSCLC remains unclear. Therefore, this review aimed to classify the management of NSCLC with driver mutations based on the gene subtype, concomitant mutation, and dynamic alternation. Then, we provide an overview of the resistant mechanism of target therapy occurring in targeted alternations ("target-dependent resistance") and in the parallel and downstream pathways ("target-independent resistance"). Thirdly, we discuss the effectiveness of ICIs for NSCLC with driver mutations and the combined therapeutic approaches that might reverse the immunosuppressive tumor immune microenvironment. Finally, we listed the emerging treatment strategies for the new oncogenic alternations, and proposed the perspective of NSCLC with driver mutations. This review will guide clinicians to design tailored treatments for NSCLC with driver mutations.

Meta-analysis of the prognostic impact of TP53 co-mutations in EGFR-mutant advanced non-small-cell lung cancer treated with tyrosine kinase inhibitors

PURPOSE

To assess the prognostic impact of TP53 mutations in EGFR-mutant advanced NSCLC patients treated with TKIs.

METHODS

Studies exploring the clinical outcomes of EGFR mutant/TP53 wild-type versus EGFR/TP53 co-mutant patients treated with TKIs were selected. Data were cumulated by adopting a fixed and random-effect model.

RESULTS

Overall, 29 trials were eligible. The PFS analysis showed that TP53 co-mutant group has shorter PFS versus EGFR mutant/TP53 wild-type group (HR = 1.67, 95% CI 1.51-1.83, heterogeneity I² =20%, p = 0.18). Patients affected by EGFR/TP53 co-mutant NSCLC have a higher chance of shorter OS versus EGFR mutant/TP53 wild type (HR= 1.89, 95% CI 1.67-2.14, heterogeneity I² = 21%; p = 0.19). The subgroup analysis showed no significant difference between first-second versus third-generation TKIs in both PFS and OS (p = 0.31, p = 0.08).

CONCLUSIONS

TP53 mutations represent a clinically relevant mechanism of resistance to EGFR-TKIs, regardless of their generation. A personalized therapeutical approach should be explored in dedicated clinical trials.

Histone deacetylase inhibitors as sanguine epitherapeutics against the deadliest lung cancer

The back-breaking resistance mechanisms generated by lung cancer cells against epidermal growth factor receptor (EGFR), KRAS and Janus kinase 2 (JAK2) directed therapies strongly prioritizes the requirement of novel therapies which are perfectly tolerated, potentially cytotoxic and can reinstate the drug-sensitivity in lung cancer cells. Enzymatic proteins modifying the post-translational modifications of nucleosome-integrated histone substrates are appearing as current targets for defeating various malignancies. Histone deacetylases (HDACs) are hyperexpressed in diverse lung cancer types. Blocking the active pocket of these acetylation erasers through HDAC inhibitors (HDACi) has come out as an optimistic therapeutic recourse for annihilating lung cancer. This article in the beginning gives an overview about lung cancer statistics and predominant lung cancer types. Succeeding this, compendium about conventional therapies and their serious drawbacks has been provided. Then, connection of uncommon expression of classical HDACs in lung cancer onset and expansion has been detailed. Moreover, keeping the main theme in view this article deeply discusses HDACi in the context of aggressive lung cancer as single agents and spotlights various molecular targets suppressed or induced by these inhibitors for engendering cytotoxic effect. Most particularly, the raised pharmacological effects achieved on using these inhibitors in concerted form with other therapeutic molecules and the cancer-linked pathways altered by this procedure are described. The positive direction towards further heightening of efficacy and the pressing requirement of exhaustive clinical assessment has been proposed as a new focus point.

Zebrafish patient-derived xenografts accurately and quickly reproduce treatment outcomes in non–small cell lung cancer patients

Zebrafish patient-derived xenograft (zPDX) models have shown great potential in predicting the short-term treatment response in various types of tumor cases. However, few studies have used zPDX models for drug screening in non–small cell lung cancer (NSCLC). We aimed to compare the treatment responses of patients with NSCLC with those of the corresponding zPDX models. Tumor cells were obtained from pleural fluid or biopsy procedures from patients with NSCLC and injected into the perivitelline space of zebrafish larvae. Then, the same antineoplastic drugs administered to the corresponding patient were tested in the successfully constructed zPDX model, for 3 days. Responses to treatment were compared. A total of 21 patients with advanced NSCLC were enrolled in our study, and 13 corresponding zPDX models were successfully established. Based on the clinical medication of enrolled patients, we provided a corresponding drug treatment to these zebrafish embryos, including epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs), pemetrexed/platinum (AP), or docetaxel/platinum (DP) administration. The chemosensitivity consistency rate between the clinical responses and those obtained from zPDXs was 76.9% (10/13). There was a high correlation between patient responses and the corresponding zPDX drug responses. Thus, zPDX can accurately and quickly reproduce patient responses to treatment with EGFR TKIs, AP, and DP and has a considerable potential to serve as a biological platform for predicting treatment effect on patients with NSCLC.

Adjuvant Immunotherapy in Patients with Early-Stage Non-small Cell Lung Cancer and Future Directions

OPINION STATEMENT

While cisplatin-based adjuvant chemotherapy has been the standard of care for the past two decades, the recent introduction of immunotherapy has heralded an important milestone in the adjuvant landscape of early-stage non-small cell lung cancer (NSCLC). The landmark approval of adjuvant atezolizumab based on disease-free survival (DFS) benefit in IMpower010 was swiftly followed by the recent data for use of adjuvant pembrolizumab in PEARLS/KEYNOTE-091, and similar trials involving other immune checkpoint inhibitors are eagerly anticipated. Although both atezolizumab and pembrolizumab demonstrated a significant DFS benefit in the intention-to-treat population, key subgroup analyses have raised questions about the role of predictive biomarkers such as PD-L1 expression and EGFR-mutation status. In this review, we examine the data from the two important trials (IMpower010 and PEARLS/KEYNOTE-091), discuss the controversies surrounding adjuvant immunotherapy including appropriate endpoints, biomarker selection and highlight key considerations in oncogene-driven NSCLC. Finally, we propose future directions including the impact of neoadjuvant therapy on developments in the adjuvant immunotherapy paradigm and role of minimal residual disease (MRD).

Cellular plasticity and immune microenvironment of malignant pleural effusion are associated with EGFR-TKI resistance in non–small-cell lung carcinoma

Malignant pleural effusion (MPE) is a complication of lung cancer that can be used as an alternative method for tissue sampling because it is generally simple and minimally invasive. Our study evaluated the diagnostic potential of non–small-cell lung carcinoma (NSCLC)-associated MPE in terms of understanding tumor heterogeneity and identifying response factors for EGFR tyrosine kinase inhibitor (TKI) therapy. We performed a single-cell RNA sequencing analysis of 31,743 cells isolated from the MPEs of 9 patients with NSCLC (5 resistant and 4 sensitive to EGFR TKI) with EGFR mutations. Interestingly, lung epithelial precursor-like cells with upregulated GNB2L1 and CAV1 expression were enriched in the EGFR TKI-resistant group. Moreover, GZMK upregulated transitional effector T cells, and plasmacytoid dendritic cells were significantly enriched in the EGFR TKI-resistant patients. Our results suggest that cellular plasticity and immunosuppressive microenvironment in MPEs are potentially associated with the TKI response of patients with EGFR-mutated NSCLC.

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ScRNA-seq reveals associations between cellular plasticity and EGFR-TKI response

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Lung epithelial progenitor-like cells are abundant in the TKI-resistant group

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HLA-II gene expression are upregulated in the epithelial cells of TKI-sensitive group

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Immunosuppressive TME was associated with the TKI resistance in NSCLC

Targeting apoptosis to manage acquired resistance to third generation EGFR inhibitors

A significant clinical challenge in lung cancer treatment is management of the inevitable acquired resistance to third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR-TKIs), such as osimertinib, which have shown remarkable success in the treatment of advanced NSCLC with EGFR activating mutations, in order to achieve maximal response duration or treatment remission. Apoptosis is a major type of programmed cell death tightly associated with cancer development and treatment. Evasion of apoptosis is considered a key hallmark of cancer and acquisition of apoptosis resistance is accordingly a key mechanism of drug acquired resistance in cancer therapy. It has been clearly shown that effective induction of apoptosis is a key mechanism for third generation EGFR-TKIs, particularly osimertinib, to exert their therapeutic efficacies and the development of resistance to apoptosis is tightly associated with the emergence of acquired resistance. Hence, restoration of cell sensitivity to undergo apoptosis using various means promises an effective strategy for the management of acquired resistance to third generation EGFR-TKIs.

Co-occurrence CDK4/6 amplification serves as biomarkers of de novo EGFR TKI resistance in sensitizing EGFR mutation non-small cell lung cancer

Despite the development of predictive biomarkers to shape treatment paradigms and outcomes, de novo EGFR TKI resistance advanced non-small cell lung cancer (NSCLC) remains an issue of concern. We explored clinical factors in 332 advanced NSCLC who received EGFR TKI and molecular characteristics through 65 whole exome sequencing of various EGFR TKI responses including; de novo (progression within 3 months), intermediate response (IRs) and long-term response (LTRs) (durability > 2 years). Uncommon EGFR mutation subtypes were significantly variable enriched in de novo resistance. The remaining sensitizing EGFR mutation subtypes (exon 19 del and L858R) accounted for 75% of de novo resistance. Genomic landscape analysis was conducted, focusing in 10 frequent oncogenic signaling pathways with functional contributions; cell cycle, Hippo, Myc, Notch, Nrf2, PI-3-Kinase/Akt, RTK-RAS, TGF-β, p53 and β-catenin/Wnt signaling. Cell cycle pathway was the only significant alteration pathway among groups with the FDR p-value of 6 × 10^-4. We found only significant q-values of < 0.05 in 7 gene alterations; CDK6, CCNE1, CDK4, CCND3, MET, FGFR4 and HRAS which enrich in de novo resistance [range 36-73%] compared to IRs/LTRs [range 4-22%]. Amplification of CDK4/6 was significant in de novo resistance, contrary to IRs and LTRs (91%, 27.9% and 0%, respectively). The presence of co-occurrence CDK4/6 amplification correlated with poor disease outcome with HR of progression-free survival of 3.63 [95% CI 1.80-7.31, p-value < 0.001]. The presence of CDK4/6 amplification in pretreatment specimen serves as a predictive biomarker for de novo resistance in sensitizing EGFR mutation.

Prognostic Value of BIM Deletion in EGFR-Mutant NSCLC Patients Treated with EGFR-TKIs: A Meta-Analysis

BACKGROUND

Resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) is inevitable in EGFR-mutant non-small-cell lung cancer (NSCLC) patients. A germline 2903 bp deletion polymorphism of Bcl-2-like protein 11 (BIM) causes reduced expression of proapoptotic BH3-only BIM protein and blocks TKI-induced apoptosis of tumor cells. Yet the association between the deletion polymorphism and response to EGFR-TKI treatment remains inconsistent among clinical observations. Thus, we performed the present meta-analysis.

METHODS

Eligible studies were identified by searching PubMed, Embase, and ClinicalTrials.gov databases prior to March 31, 2021. Hazard ratios (HRs) and 95% confidence intervals (CIs) of progression-free survival (PFS) and overall survival (OS) and odds ratios (ORs) and 95% CIs of objective response rate (ORR) and disease control rate (DCR) were calculated by using a random effects model. Sensitivity, metaregression, and publication bias analyses were also performed.

RESULTS

A total of 20 datasets (3003 EGFR-mutant NSCLC patients receiving EGFR-TKIs from 18 studies) were included. There were 475 (15.8%) patients having the 2903-bp intron deletion of BIM and 2528 (84.2%) wild-type patients. BIM deletion predicted significantly shorter PFS (HR = 1.35, 95% CI: 1.10-1.64, P = 0.003) and a tendency toward an unfavorable OS (HR = 1.22, 95% CI: 0.99-1.50, P = 0.068). Patients with deletion polymorphism had lower ORR (OR = 0.60, 95% CI: 0.42-0.85, P = 0.004) and DCR (OR = 0.59, 95% CI: 0.38-0.90, P = 0.014) compared with those without deletion.

CONCLUSION

BIM deletion polymorphism may confer resistance to EGFR-TKIs and can be used as a biomarker to predict treatment response to EGFR-TKIs in EGFR-mutant NSCLC patients from Asian populations.

Nuclear Pore Glycoprotein 62 Genetic Variant rs9523 is Associated with Clinical Outcomes of Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors in Lung Adenocarcinoma Patients

Introduction

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have represented the prototype of targeted therapy in NSCLC. Patients with EGFR-mutant lung adenocarcinoma extract an extraordinary clinical benefit from EGFR-TKIs. However, the extent and duration of these responses are heterogeneous, suggesting the existence of genetic modifiers affecting an individual’s response to TKIs. We investigated whether genetic variants in miRNA binding sites are associated with the clinical outcome of EGFR-TKIs in lung adenocarcinoma patients.

Methods

One hundred SNPs at miRNA binding sites in cancer-related genes were selected for the analysis using the crosslinking, ligation and sequencing of hybrids (CLASH) and CancerGenes database. qRT-PCR and luciferase assays were conducted to evaluate the functional relevance of the SNPs.

Results

NUP62 rs9523A>G were significantly associated with worse response to EGFR-TKIs, overall survival (OS), and progression-free survival (PFS). The other three SNPs (DVL2 rs2074216G>A, ARF1 rs11541557G>T, and UHRF1 rs2261988C>A) were significantly associated with worse OS and PFS. The rs9523A>G was significantly associated with decreased NUP62 expression in tumor tissues. In addition, a significantly decreased luciferase activity was noted in NUP62 rs9523 G allele compared to A allele.

Conclusion

Genetic variants in miRNA binding sites, especially NUP62 rs9523A>G, may be useful in predicting the clinical outcomes of EGFR-mutant lung adenocarcinoma patients treated with EGFR-TKIs.

Non-Small Cell Lung Cancer Harboring Concurrent EGFR Genomic Alterations: A Systematic Review and Critical Appraisal of the Double Dilemma

The molecular pathways which promote lung cancer cell features have been broadly explored, leading to significant improvement in prognostic and diagnostic strategies. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have dramatically altered the treatment approach for patients with metastatic non-small cell lung cancer (NSCLC). Latest investigations by using next-generation sequencing (NGS) have shown that other oncogenic driver mutations, believed mutually exclusive for decades, could coexist in EGFR-mutated NSCLC patients. However, the exact clinical and pathological role of concomitant genomic aberrations needs to be investigated. In this systematic review, we aimed to summarize the recent data on the oncogenic role of concurrent genomic alterations, by specifically evaluating the characteristics, the pathological significance, and their potential impact on the treatment approach.

PTEN Loss as a Predictor of Tumor Heterogeneity and Poor Prognosis in Patients With EGFR-mutant Advanced Non-small-cell Lung Cancer Receiving Tyrosine Kinase Inhibitors

BACKGROUND

Rapid disease progression of patients with advanced epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) has been recently associated with tumor heterogeneity, which may be mirrored by coexisting concomitant alterations. The aim of this analysis was to investigate the correlation between loss of function of PTEN and the efficacy of tyrosine kinase inhibitors in this population.

MATERIALS AND METHODS

Archival tumor blocks from patients with EGFR-mutant NSCLC who were administered upfront tyrosine kinase inhibitors were retrospectively collected. The status of 4 genes (PTEN, TP53, c-MET, IGFR) was evaluated by immunohistochemistry, and it was correlated with overall response rate, overall survival (OS), and progression-free survival (PFS).

RESULTS

Fifty-one patients were included. In multivariate analysis, PTEN loss (hazard ratio [HR], 3.46; 95% confidence interval [CI], 1.56-7.66; P = .002), IGFR overexpression (HR, 2.22; 95% CI, 1.03-4.77; P = .04), liver metastases (HR, 3.55; 95% CI, 1.46-8.65; P = .005), and Eastern Cooperative Oncology Group performance status (ECOG PS) ≥ 1 (HR, 2.57; 95% CI, 1.04-6.34; P = .04) were significantly associated with shorter PFS. Patients with PTEN loss had a median PFS of 6 months (2-year PFS, 11.6%), whereas patients without PTEN loss had a median PFS of 18 months (2-year PFS, 43.6%) (log-rank P < .005). In the multivariate analysis, PTEN loss (HR, 5.92; 95% CI, 2.37-14.81; P < .005), liver metastases (HR, 2.63; 95% CI, 1.06-6.51; P = .037), and ECOG PS ≥ 1 (HR, 2.80; 95% CI, 1.15-6.81; P = .024) were significantly associated with shorter OS. Patients with PTEN loss had a median OS of 6 months (2-year OS, 12.2%), whereas in patients without PTEN loss, OS was not reached (2-year OS, 63.9%) (log-rank P < .0005).

CONCLUSIONS

A low-cost and reproducible immunohistochemistry assay for PTEN loss analysis represents a potential tool for identifying tumor heterogeneity in patients with advanced EGFR-mutant NSCLC.

Estrogen Receptor β1 Expression Patterns Have Different Effects on Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors' Treatment Response in Epidermal Growth Factor Receptor Mutant Lung Adenocarcinoma

Estrogen receptor β (ERβ) can regulate cellular signaling through non-genomic mechanisms, potentially promoting resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). However, the mechanisms underlying the ERβ-mediated resistance to EGFR TKIs remain poorly understood. In this study, we investigated the role of the interaction between ERβ1 and ERβ5 in non-genomic signaling in lung adenocarcinoma. We established PC9 cell lines stably overexpressing ERβ1 or ERβ1/ERβ5. Immunofluorescence revealed that ERβ5 overexpression partly retained ERβ1 in the cytoplasm. Immunoblotting analyses revealed that EGFR pathway activation levels were higher in PC9/ERβ1/5 cells than those in PC9/ERβ1 or control PC9 cells. In the presence of estradiol, PI3K/AKT/mTOR pathway activation levels were higher in ERβ1/5-expressing cells than those in ERβ1-expressing cells. Additionally, PC9/ERβ1/5 cells were less prone to the cytotoxic and pro-apoptotic effects of gefitinib compared with PC9/ERβ1 or control PC9 cells. Cytoplasmic ERβ1 was associated with poor progression-free survival in lung cancer patients treated with EGFR TKIs. These results suggest that cytoplasmic ERβ1 was responsible for EGFR TKI resistance slightly through non-genomic mechanism in EGFR mutant lung adenocarcinoma.

The emergence of various genetic alterations mediated the Osimertinib resistance of a patient harboring heterozygous germline EGFR T790M: a case report

Epidermal growth factor receptor (EGFR) T790M is the major mechanism mediating resistance to first- and second-generation EGFR tyrosine kinase inhibitors. Despite the high frequency of EGFR activating mutations among East Asian lung cancer patients, germline T790M has been the subject of very little research. Questions remain as to whether germline T790M develops resistance to Osimertinib and if so, through which mechanisms. This study examined a patient harboring germline EGFR T790M who acquired resistance to Osimertinib therapy. After the failure of first-line icotinib therapy, which was administered for only 3 months, targeted next-generation sequencing of plasma samples collected at icotinib progression and the re-analysis of the baseline tissue biopsy sample revealed EGFR T790M with allelic frequencies approximating 50%. Lymphocyte genomic deoxyribonucleic acid (DNA) sequencing confirmed the germline heterozygous status of the T790M mutation. In addition to the EGFR T790M, a concurrent EGFR L858R was detected from the baseline tissue sample. Osimertinib therapy was initiated resulting in a partial response within 1 month of the commencement of the therapy. After 15.2 months of Osimertinib therapy, disease progression was evaluated due to the presence of pleural effusion. The targeted sequencing of plasma and pleural effusion samples revealed the emergence of EGFR G719A, tumor protein p53 (TP53) Q136X, and the co-amplification of Cyclin D1, fibroblast growth factor (FGF) 19, FGF3, and FGF4. This case highlights the importance of conducting next-generation sequencing–based molecular testing during both diagnostic and disease progression assessments to reveal sensitizing mutations and mutations that could mediate primary and acquired resistance to targeted therapeutics.

Concurrent Genetic Alterations and Other Biomarkers Predict Treatment Efficacy of EGFR-TKIs in EGFR-Mutant Non-Small Cell Lung Cancer: A Review

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) greatly improve the survival and quality of life of non-small cell lung cancer (NSCLC) patients with EGFR mutations. However, many patients exhibit de novo or primary/early resistance. In addition, patients who initially respond to EGFR-TKIs exhibit marked diversity in clinical outcomes. With the development of comprehensive genomic profiling, various mutations and concurrent (i.e., coexisting) genetic alterations have been discovered. Many studies have revealed that concurrent genetic alterations play an important role in the response and resistance of EGFR-mutant NSCLC to EGFR-TKIs. To optimize clinical outcomes, a better understanding of specific concurrent gene alterations and their impact on EGFR-TKI treatment efficacy is necessary. Further exploration of other biomarkers that can predict EGFR-TKI efficacy will help clinicians identify patients who may not respond to TKIs and allow them to choose appropriate treatment strategies. Here, we review the literature on specific gene alterations that coexist with EGFR mutations, including common alterations (intra-EGFR [on target] co-mutation, TP53, PIK3CA, and PTEN) and driver gene alterations (ALK, KRAS, ROS1, and MET). We also summarize data for other biomarkers (e.g., PD-L1 expression and BIM polymorphisms) associated with EGFR-TKI efficacy.

Efficacy of EGFR tyrosine kinase inhibitors in patients having EGFR-activating mutations with or without BIM polymorphisms

PURPOSE

Patients with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer with BIM deletion polymorphism may have a limited response to EGFR tyrosine kinase inhibitors (EGFR-TKIs). However, some results of previous reports are discordant. It is necessary to evaluate the relationship between BIM polymorphism and the efficacy of EGFR-TKIs.

METHODS

We retrospectively analyzed patients treated with EGFR-TKIs. We collected serum samples from patients before EGFR-TKI administration. We analyzed BIM deletion polymorphism and BIM single nucleotide polymorphism in exon 5 c465C > T by the Invader^® assay.

RESULTS

BIM deletion polymorphism was identified in 27 of 194 patients (13.9%). BIM single nucleotide polymorphism was identified in 29 of 194 patients (14.9%). The overall response ratio was 81.5% in patients with BIM deletion polymorphism, 89.7% with BIM single nucleotide polymorphism, and 83.6% with BIM wild type. Median progression-free survival was 10.3 months with BIM deletion polymorphism, 8.5 months with BIM single nucleotide polymorphism, and 10.4 months with BIM wild type. Overall survival was 38.4 months with BIM deletion polymorphism, 29.1 months with BIM single nucleotide polymorphism, and 31.6 months with BIM wild type. There were no significant differences between the groups in overall response ratio, progression-free survival, and overall survival.

CONCLUSIONS

BIM polymorphism does not affect EGFR-TKI efficacy.

Multiplexed molecular profiling of lung cancer with malignant pleural effusion using next generation sequencing in Chinese patients

Lung cancer is the most common type of cancer and the leading cause of cancer-associated death worldwide. Malignant pleural effusion (MPE), which is observed in ~50% of advanced non-small cell lung cancer (NSCLC) cases, and most frequently in lung adenocarcinoma, is a common complication of stage III-IV NSCLC, and it can be used to predict a poor prognosis. In the present study, multiple oncogene mutations were detected, including 17 genes closely associated with initiation of advanced lung cancer, in 108 MPE samples using next generation sequencing (NGS). The NGS data of the present study had broader coverage, deeper sequencing depth and higher capture efficiency compared with NGS findings of previous studies on MPE. In the present study, using NGS, it was demonstrated that 93 patients (86%) harbored EGFR mutations and 62 patients possessed mutations in EGFR exons 18-21, which are targets of available treatment agents. EGFR L858R and exon 19 indel mutations were the most frequently observed alterations, with frequencies of 31 and 25%, respectively. In 1 patient, an EGFR amplification was identified and 6 patients possessed a T790M mutation. ALK + EML4 gene fusions were identified in 6 patients, a ROS1 + CD74 gene fusion was detected in 1 patient and 10 patients possessed a BIM (also known as BCL2L11) 2,903-bp intron deletion. In 4 patients, significant KRAS mutations (G12D, G12S, G13C and A146T) were observed, which are associated with resistance to afatinib, icotinib, erlotinib and gefitinib. There were 83 patients with ERBB2 mutations, but only two of these mutations were targets of available treatments. The results of the present study indicate that MPE is a reliable specimen for NGS based detection of somatic mutations.

Coexisting EGFR and TP53 Mutations in Lung Adenocarcinoma Patients Are Associated With COMP and ITGB8 Upregulation and Poor Prognosis

The heterogeneity of lung adenocarcinoma is driven by key mutations in oncogenes. To determine the gene expression, single nucleotide polymorphisms, and co-mutations participating in the initiation and progression of lung adenocarcinoma, we comprehensively analyzed the data of 491 patients from The Cancer Genome Atlas. Using log-rank and Kruskal-Wallis analysis, Oncoprint, Kaplan-Meier survival plots, and a nomogram, we found that EGFR^L858R with co-mutation TP53 was significant prognostic determinant versus that with co-wild TP53 (hazard ratio, 2.77, P = 0.012). Further gene co-expression network and functional enrichment analysis indicated that co-mutation of EGFR^L858R/TP53 increases the expression of COMP and ITGB8, which are involved in extracellular matrix organization and cell surface receptor signaling pathways, thus contributing to poor prognosis in lung adenocarcinoma. Validation was performed using three GEO profiles along with colony formation and CCK-8 assays for proliferation, transwell and wound-healing for migration in transfected H1299 and A549 cell lines. To the best of our knowledge, these results are the first to indicate that patients harboring the co-mutation of EGFR^L858R/TP53 show increased expression of COMP and ITGB8, which participate in extracellular matrix dysfunction and can be used as prognostic biomarkers in patients with lung adenocarcinoma.

Advances in nanotechnology-based delivery systems for EGFR tyrosine kinases inhibitors in cancer therapy

Oral tyrosine kinase inhibitors (TKIs) against epidermal growth factor receptor (EGFR) family have been introduced into the clinic to treat human malignancies for decades. Despite superior properties of EGFR-TKIs as small molecule targeted drugs, their applications are still restricted due to their low solubility, capricious oral bioavailability, large requirement of daily dose, high binding tendency to plasma albumin and initial/acquired drug resistance. Nanotechnology is a promising tool to improve efficacy of these drugs. Through non-oral routes. Various nanotechnology-based delivery approaches have been developed for providing efficient delivery of EGFR-TKIs with a better pharmacokinetic profile and tissue-targeting ability. This review aims to indicate the advantage of nanocarriers for EGFR-TKIs delivery.

Survival Implications of De Novo Versus Recurrent Metastatic Non-Small Cell Lung Cancer

OBJECTIVES

Metastatic non-small cell lung cancer (NSCLC) has a poor prognosis. Most patients present with stage IV, and many patients treated curatively with stage I to III develop recurrent metastatic disease. It is unknown whether the natural history differs between patients with recurrent versus de novo metastatic NSCLC. We hypothesized that de novo metastatic status is associated with decreased overall survival compared with recurrent metastatic disease.

MATERIALS AND METHODS

A retrospective review was completed of all patients with NSCLC referred to BC Cancer from 2005 to 2012. Two cohorts were created; de novo metastatic disease and patients treated with curative intent (surgery or radiotherapy) that developed recurrent, metastatic disease. Information was collected on known prognostic and predictive factors. Overall survival was calculated from the date of diagnosis of metastatic disease.

RESULTS

A total of 9651 patients were evaluated, 5782 (60%) with de novo stage IV disease, and 3869 (40%) with stage I to III disease. Of the 1658 patients who received curative therapy for stage I to III disease, 757 (46%) developed metastases. Patients in the de novo cohort versus recurrent cohort were more likely male (52% vs. 48%), have poorer performance status (Eastern Cooperative Oncology Group≥2 50% vs. 44%), and receive no palliative systemic therapy (67% vs. 61%). The median overall survival in the de novo cohort was 4.7 versus 6.9 m in the recurrent cohort (P<0.001). De novo status was associated with shorter overall survival and this remained significant in a multivariate model that incorporated known prognostic factors.

CONCLUSIONS

In a large population-based study of NSCLC, de novo metastatic status was independently associated with decreased overall survival from the time of metastatic disease diagnosis.

Drug resistance to targeted therapeutic strategies in non-small cell lung cancer

Rapidly developing molecular biology techniques have been employed to identify cancer driver genes in specimens from patients with non-small cell lung cancer (NSCLC). Inhibitors and antibodies that specifically target driver gene-mediated signaling pathways to suppress tumor growth and progression are expected to extend the survival time and further improve the quality of life of patients. However, the health of patients with advanced and metastatic NSCLC presents significant challenges due to treatment resistance, mediated by cancer driver gene alteration, epigenetic alteration, and tumor heterogeneity. In this review, we discuss two different resistance mechanisms in NSCLC targeted therapies, namely changes in the targeted oncogenes (on-target resistance) and changes in other related signaling pathways (off-target resistance) in tumor cells. We highlight the conventional mechanisms of drug resistance elicited by the complex heterogeneous microenvironment of NSCLC during targeted therapy, including mutations in epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), the receptor tyrosine kinase ROS proto-oncogene 1 (ROS1), and the serine/threonine-protein kinase BRAF (v-Raf murine sarcoma viral oncogene homolog B). We also discuss the mechanism of action of less common oncoproteins, as in-depth understanding of these molecular mechanisms is important for optimizing treatment strategies.

The Effects and Mechanisms by which Saikosaponin-D Enhances the Sensitivity of Human Non-small Cell Lung Cancer Cells to Gefitinib

Non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR)-sensitive mutations benefit from epidermal growth factor receptor tyrosine kinase inhibitors (EGFR- TKIs). However, drug resistance is a major cause of therapeutic failure. This study examined whether saikosaponin-d (SSD) enhances the anti-tumor effect of gefitinib in NSCLC cells. Cell Counting Kit-8 (CCK-8) was used to determine cell viability. Cell apoptosis was examined by flow cytometry. Signal transducer and activator of transcription (STAT3), phosphor-STAT3 (P-STAT3), and B-cell lymphoma 2 (Bcl-2) were detected by Western blot. An HCC827/GR tumor model was established to observe the effect of combination therapy in vivo. The combination of SSD with gefitinib had an enhanced inhibitory effect by reducing cell viability and inducing cells apoptosis in NSCLC cells. Furthermore, SSD decreased and increased the expression of P-STAT3 and Bcl-2, respectively. Down-regulated STAT3 promoted the sensitivity of lung cancer cells to gefitinib. The results of animal experiments also showed that SSD enhanced the anti-tumor effect of gefitinib. These results indicated that the combination of SSD with gefitinib had an increased antitumor effect in NSCLC cells and that the molecular mechanisms were associated with the inhibition of STAT3/Bcl-2 signaling pathway. Our findings suggest a promising approach for the treatment of NSCLC patients with EGFR-TKI resistance.

BMSC-derived leptin and IGFBP2 promote erlotinib resistance in lung adenocarcinoma cells through IGF-1R activation in hypoxic environment

EGFR-TKIs such as erlotinib and gefitinib have been introduced into the first-line treatment for patients having a mutation of deletion in exon 19 or L858R missense mutations in exon 21. Almost all patients who respond to EGFR-TKIs at first place eventually develop acquired resistance after several months of therapy. The secondary mutations and bypass signaling activation are involved in the generation of the resistance. Hypoxia in non-small cell lung cancer (NSCLC) is an important factor in treatment resistance including radiotherapy, chemotherapy and EGFR-TKI therapy. In this study, the effect of hypoxic cancer microenvironment in the bypass signaling activation was investigated. We found that bone marrow-derived mesenchymal stem cells (BMSCs) residing in the hypoxic solid cancer microenvironment highly produced molecules associated with adipocytes including adipokine leptin and IGFBPs. Leptin could induce the resistance of lung cancer cells to erlotinib through activating IGF-1R signaling. IGFBP2 counteracted the activation role of IGF-1 and induced erlotinib resistance by activating IGF-1R signaling in an IGF-1 independent manner. IGFBP2 had synergistic effect with leptin to induce erlotinib resistance. Leptin and IGFBP2 may be predictive factors for acquired resistance for EGFR-TKIs.

The Impact of Clinical Factors, ALK Fusion Variants, and BIM Polymorphism on Crizotinib-Treated Advanced EML4-ALK Rearranged Non-small Cell Lung Cancer

Patients' clinical factors and genetics factors such as anaplastic lymphoma kinase (ALK) fusion variants and BIM (Bcl-2-like 11) polymorphism were reported to be associated with clinical outcome in crizotinib-treated advanced non-small cell lung cancer (NSCLC). However, the results were still controversial. We analyzed outcome of 54 patients with known ALK fusion variants who received crizotinib for advanced NSCLC. Thirty of them had successful BIM polymorphism analysis and 6 (20%) had a BIM deletion. Multivariate Cox regression analysis found that previous anticancer therapy [adjusted hazard ratio (aHR) 1.35, 95% confidence interval (CI), 1.04–1.76 for each additional line of therapy, p = 0.025] and Eastern Cooperative Oncology Group (ECOG) performance status ≥2 (aHR 8.35, 95% CI, 1.52–45.94, p = 0.015) were independent factors for progression-free survival (PFS). Only ECOG performance status ≥2 (aHR 7.20, 95% CI, 1.27–40.79, p = 0.026) was an independent factor for overall survival (OS). Neither ALK fusion variants nor the presence of a BIM deletion was associated with crizotinib PFS or OS. After adjusting with clinical factors, different ALK variants and BIM polymorphism might not be independent factors for crizotinib PFS or OS in advanced NSCLC with ALK rearrangement.

Intrinsic resistance to EGFR-Tyrosine Kinase Inhibitors in EGFR-Mutant Non-Small Cell Lung Cancer: Differences and Similarities with Acquired Resistance

Activating mutations in the epidermal growth factor receptor gene occur as early cancer-driving clonal events in a subset of patients with non-small cell lung cancer (NSCLC) and result in increased sensitivity to EGFR-tyrosine-kinase-inhibitors (EGFR-TKIs). Despite very frequent and often prolonged clinical response to EGFR-TKIs, virtually all advanced EGFR-mutated (EGFRM+) NSCLCs inevitably acquire resistance mechanisms and progress at some point during treatment. Additionally, 20-30% of patients do not respond or respond for a very short time (<3 months) because of intrinsic resistance. While several mechanisms of acquired EGFR-TKI-resistance have been determined by analyzing tumor specimens obtained at disease progression, the factors causing intrinsic TKI-resistance are less understood. However, recent comprehensive molecular-pathological profiling of advanced EGFRM+ NSCLC at baseline has illustrated the co-existence of multiple genetic, phenotypic, and functional mechanisms that may contribute to tumor progression and cause intrinsic TKI-resistance. Several of these mechanisms have been further corroborated by preclinical experiments. Intrinsic resistance can be caused by mechanisms inherent in EGFR or by EGFR-independent processes, including genetic, phenotypic or functional tumor changes. This comprehensive review describes the identified mechanisms connected with intrinsic EGFR-TKI-resistance and differences and similarities with acquired resistance and among clinically implemented EGFR-TKIs of different generations. Additionally, the review highlights the need for extensive pre-treatment molecular profiling of advanced NSCLC for identifying inherently TKI-resistant cases and designing potential combinatorial targeted strategies to treat them.

Identification of genetic alterations associated with primary resistance to EGFR-TKIs in advanced non-small-cell lung cancer patients with EGFR sensitive mutations

Background

Identification of activated epidermal growth factor receptor (EGFR) mutations and application of EGFR-tyrosine kinase inhibitors (EGFR-TKIs) have greatly changed the therapeutic strategies of non-small-cell lung cancer (NSCLC). However, the long-term efficacy of EGFR-TKI therapy is limited due to the development of drug resistance. The aim of this study was to investigate the correlation between the aberrant alterations of 8 driver genes and the primary resistance to EGFR-TKIs in advanced NSCLC patients with activated EGFR mutations.

Methods

We retrospectively reviewed the clinical data from 416 patients with stage III/IV or recurrent NSCLC who received an initial EGFR-TKI treatment, from April 2004 and March 2011, at the Sun Yat-sen University Cancer Center. Several genetic alterations associated with the efficacy of EGFR-TKIs, including the alterations in BIM, ALK, KRAS, PIK3CA, PTEN, MET, IGF1R, and ROS1, were detected by the routine clinical technologies. The progression-free survival (PFS) and overall survival (OS) were compared between different groups using Kaplan–Meier survival analysis with the log-rank test. A Cox regression model was used to estimate multivariable-adjusted hazard ratios (HRs) and their 95% confidence intervals (95% CIs) associated with the PFS and OS.

Results

Among the investigated patients, 169 NSCLC patients harbored EGFR-sensitive mutations. EGFR-mutant patients having PTEN deletion had a shorter PFS and OS than those with intact PTEN (P = 0.003 for PFS, and P = 0.034 for OS). In the combined molecular analysis of EGFR signaling pathway and resistance genes, we found that EGFR-mutant patients coexisted with aberrant alterations in EGFR signaling pathway and those having resistant genes had a statistically poorer PFS than those without such alterations (P < 0.001). A Cox proportional regression model determined that PTEN deletion (HR = 4.29,95% CI = 1.72–10.70) and low PTEN expression (HR = 1.96, 95% CI = 1.22–3.13), MET FISH + (HR = 2.83,95% CI = 1.37–5.86) were independent predictors for PFS in patients with EGFR-TKI treatment after adjustment for multiple factor.

Conclusions

We determined that the coexistence of genetic alterations in cancer genes may explain primary resistance to EGFR-TKIs.

Electronic supplementary material

The online version of this article (10.1186/s40880-019-0354-z) contains supplementary material, which is available to authorized users.

BIM deletion polymorphism predicts poor response to EGFR-TKIs in nonsmall cell lung cancer: An updated meta-analysis

BACKGROUND

A germline deletion in BIM (B cell lymphoma-2-like 11) gene has been shown to impair the apoptotic response to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in vitro but its impact on response to EGFR-TKIs in patients of nonsmall cell lung cancer (NSCLC) remains controversial.

METHODS

Eligible literature were searched and screened. Objective response rate (ORR) and disease control rate (DCR) were extracted and aggregated with odds ratio (OR). Hazard ratio (HR) and 95% confidence interval (CI) for progression-free survival (PFS) and overall survival (OS) were extracted and aggregated based on random-effect model.

RESULTS

Fourteen studies including 2694 NSCLC patients were eligible. Individuals harboring BIM deletion polymorphism had inferior ORR (OR = 0.49, 95% CI: 0.34-0.70, P < .001), inferior DCR (OR = 0.50, 95% CI: 0.30-0.84, P = .009). Patients with BIM deletion had shorter OS despite of the heterogeneity between countries (in subgroup of South Korea and Taiwan, HR = 1.34, 95% CI: 1.18-1.53, P < .001; in subgroup of other countries, HR = 2.43, 95% CI: 2.03-2.91, P < .001). The pooled analysis of PFS showed great heterogeneity (I = 79%). All the reported characteristics did not account for the heterogeneity. However, 2 subgroups could be obtained through sensitivity analysis. In one subgroup, patients with BIM deletion polymorphism had shorter PFS (HR = 2.03, 95% CI: 1.71-2.40, P < .001), while in the other subgroup, no significant difference was observed (HR = 0.92, 95% CI: 0.79-1.06, P = .25).

CONCLUSION

NSCLC patients with BIM deletion polymorphism show poor ORR, DCR, and OS after EGFR-TKIs treatment. BIM deletion polymorphism indicates poor response to EGFR-TKIs, and it could be used as a predictor to identify those who would benefit from EGFR-TKIs in NSCLC patients.

[Molecular Mechanism and Progression of Primary Resistance to EGFR-TKI - Analysis of 2 Cases]

酪氨酸激酶抑制剂(tyrosine-kinase inhibitor, TKI)类药物已经被证实对表皮生长因子受体(epidermal growth factor receptor, EGFR)敏感突变的晚期非小细胞肺癌(non-small cell lung cancer, NSCLC)患者有很好的疗效，优于化疗。但仍有部分敏感突变的患者出现原发性耐药。耐药的原因尚不明确，可能与EGFR基因的敏感突变与耐药突变共存、EGFR通路下游基因突变、MET扩增、BIM缺失多态性等因素相关。本文分享了2例原发性耐药病历并进行了原因分析。

De Novo HER2 S310Y mutation associates with poor response to EGFR tyrosine kinase inhibitor in activating EGFR-mutant NSCLC patient: A case report

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are highly effective in treating lung cancer patients with epidermal growth factor receptor (EGFR)-activating mutations. However, intrinsic resistances of tyrosine kinase inhibitor (TKI) have been reported in 20%–30% of cases. The majority of patients who have primary resistance to EGFR-TKI harbor an insertion in EGFR exon 20 and T790M mutation. Other previously described primary resistance mechanisms include MET amplification, ALK fusion, and KRAS mutation. However, other primary resistance mechanisms have not been fully investigated. Here, we present a 68-year-old Chinese never smoke female with postoperative recurrence of bone and liver metastases after 3 years of surgery, exhibiting combined EGFR and HER2 S310Y mutation by next-generation sequencing panel analysis. The patient responded to gefitinib treatment poorly and showed progressive disease with rapid growth of lung and liver metastasis. This is the first report of activated EGFR mutation patient with a HER2 S310Y mutation had progressed on EGFR-TKI. We suggest that HER2 S310Y mutation probably leads to EGFR-TKI primary resistance in EGFR-mutated NSCLC.

Synthesis and Biological Evaluation of Some Novel Thiophene-bearing Quinazoline Derivatives as EGFR Inhibitors

Background:

With the approval of gefitinib, erlotinib, afatinib, and osimertinib for clinical use, targeting Epidermal Growth Factor Receptor (EGFR) has been intensively pursued. Similar to most therapies, challenges related to the treatment resistance against these drugs have emerged over time, so new EGFR Tyrosine Kinase Inhibitors (TKIs) need to be developed. This study aimed to investigate the potential use of a series of thiophene-bearing quinazoline derivatives as EGFR inhibitors. We designed and synthesized nine quinazolin derivatives, among which five compounds (5e, 5f, 5g, 5h, and 5i) were reported for the first time. </P><P> Methods: Two cancer cell lines, A431 (overexpressing EGFR) and A549 (EGFR wild-type and Kras mutation), were treated by these compounds and subjected to MTT assay. The A431 cells were selected for further treatment (5e) and Western blot analysis.

Results:

Although the compounds exerted no obvious effects on the proliferation of A549 cells, seven out of the nine compounds significantly inhibited the growth of A431 cells. In particular, the IC50 values of 5e and erlotinib were nearly equal. Western blot results showed that 5e significantly inhibited EGFR autophosphorylation in A431 cells. Structure-activity relationships indicated that quinazolines bearing 6,7-side chains were more potent than those unsubstituted at the 6,7-positions. Moreover, electron-withdrawing hydrophobic groups on the 5-position of the thiophene were preferred, such as chlorine or bromine atom.

Conclusion:

Nine 4-aminoquinazolin derivatives were designed, synthesized, and evaluated against A431 and A549 cell lines. Seven compounds significantly inhibited the growth of A431 cells. In particular, 5e possessed similar antitumor potency to that of erlotinib.

High PD-L1 expression correlates with primary resistance to EGFR-TKIs in treatment naïve advanced EGFR-mutant lung adenocarcinoma patients

OBJECTIVES

The main objective was to investigate the relationship between Programmed cell Death-ligand 1 (PD-L1) expression levels and the frequency of primary resistance to Epidermal Growth Factor Receptor (EGFR)-Tyrosine Kinase Inhibitor (TKI) in treatment naïve advanced EGFR-mutant lung adenocarcinoma patients.

MATERIALS AND METHODS

From 2012-2017, we enrolled advanced EGFR-mutant lung adenocarcinoma patients who displayed primary resistance to EGFR-TKI therapy, along with patients with disease control, and patients experiencing either stable disease or partial response to EGFR-TKI treatment.

RESULTS

Sixty-six patients were enrolled as the primary resistance group, while 57 patients were included as the disease control group. Fifteen-five (22.7%) patients had a PD-L1 Tumor Proportion Score (TPS) ≧50% in the primary resistance group, with only one patient (1.8%) having that score in the disease control group (P＜0.001). Twenty (30.3%) patients had a PD-L1 ≧25% in the primary resistance group, with 2 (3.5%) patients having that level in the disease control group (P＜0.001). Thirty (45.5%) patients had a PD-L1 ≧1% in the primary resistance group, with 7 (12.3%) patients at that level in the disease control group (P = 0.001). Patients with a PD-L1≧1% displayed a higher incidence of primary resistance to EGFR-TKIs than those with a PD-L1＜1% (Odds Ratio (OR), 5.95; 95% Confidence Interval (CI), 2.35-15.05; P＜0.001). The phenomenon existed still when the cutoff value was changed to both 25% (OR, 11.96; 95% CI, 2.65-53.87; P = 0.001) and 50% (OR, 16.47; 95% CI, 2.10-129.16; P = 0.008). The estimated median Progression-free Survival (PFS) rate was 7.3 months in patients with a PD-L1＜1%, 2.1 months in patients with a PD-L1≧1%, 1.8 months in patients with a PD-L1≧25%, and 1.6 months in patients with a PD-L1≧50%.

CONCLUSIONS

Treatment for advanced EGFR-mutant lung adenocarcinoma patients displaying a higher PD-L1 expression level experienced a higher frequency of primary resistance to EGFR-TKIs.

Malignant mixed ovarian germ cell tumor composed of immature teratoma, yolk sac tumor and embryonal carcinoma harboring an EGFR mutation: a case report

Malignant mixed ovarian germ cell tumors are very rare, accounting for ~5.3% of all malignant ovarian germ cell tumors (MOGCTs), with a very high degree of malignancy. The treatment of patients with persistent, refractory, or platinum-resistant MOGCT is not well defined. The objective of this case report was to analyze the importance of chemotherapy, salvage surgery and target therapy in the treatment of a patient with refractory OGCT after first-line chemotherapy failure. We reported a 34 year-old woman suffered from advanced refractory MOGCT after first-line chemotherapy, cytoreductive surgery, and a series of chemotherapy. The genetic test shows she is a carrier of EGFR: p.L858R mutation. Based on genetic testing result, she received icotinib which targeted for EGFR mutation, but the tumor progressed. After a secondary cytoreductive surgery, she exhibited a partial response and continued to receive chemotherapy. This suggests that salvage surgery may be considered for patients with persistent or refractory MOGCTs when no effective systemic treatment option is available. Targeted therapies based on gene sequencing may provide a new option; however, its efficacy and related resistance mechanisms still need to be verified by further study.

Oligosaccharyltransferase Inhibition Overcomes Therapeutic Resistance to EGFR Tyrosine Kinase Inhibitors

Asparagine (N)-linked glycosylation is a posttranslational modification essential for the function of complex transmembrane proteins. However, targeting glycosylation for cancer therapy has not been feasible due to generalized effects on all glycoproteins. Here, we perform sensitivity screening of 94 lung cancer cell lines using NGI-1, a small-molecule inhibitor of the oligosaccharyltransferase (OST) that partially disrupts N-linked glycosylation, and demonstrate a selective loss of tumor cell viability. This screen revealed NGI-1 sensitivity in just 11 of 94 (12%) cell lines, with a significant correlation between OST and EGFR inhibitors. In EGFR-mutant non-small cell lung cancer with EGFR tyrosine kinase inhibitor (TKI) resistance (PC9-GR, HCC827-GR, and H1975-OR), OST inhibition maintained its ability to induce cell-cycle arrest and a proliferative block. Addition of NGI-1 to EGFR TKI treatment was synthetic lethal in cells resistant to gefitinib, erlotinib, or osimertinib. OST inhibition invariably disrupted EGFR N-linked glycosylation and reduced activation of receptors either with or without the T790M TKI resistance mutation. OST inhibition also dissociated EGFR signaling from other coexpressed receptors like MET via altered receptor compartmentalization. Translation of this approach to preclinical models was accomplished through synthesis and delivery of NGI-1 nanoparticles, confirmation of in vivo activity through molecular imaging, and demonstration of significant tumor growth delay in TKI-resistant HCC827 and H1975 xenografts. This therapeutic strategy breaks from kinase-targeted approaches and validates N-linked glycosylation as an effective target in tumors driven by glycoprotein signaling.Significance:EGFR-mutant NSCLC is incurable despite the marked sensitivity of these tumors to EGFR TKIs. These findings identify N-linked glycosylation, a posttranslational modification common to EGFR and other oncogenic signaling proteins, as an effective therapeutic target that enhances tumor responses for EGFR-mutant NSCLC. Cancer Res; 78(17); 5094-106. ©2018 AACR.

Combined treatment with metformin and gefitinib overcomes primary resistance to EGFR-TKIs with EGFR mutation via targeting IGF-1R signaling pathway

Aim

Although EGFR tyrosine kinase inhibitors (TKIs) have shown dramatic effects against sensitizing EGFR mutations in non-small cell lung cancer (NSCLC), ~20%–30% of NSCLC patients with EGFR-sensitive mutation exhibit intrinsic resistance to EGFR-TKIs. The purpose of the current study was to investigate the enhanced antitumor effect of metformin (Met), a biguanide drug, in combination with gefitinib (Gef) in primary resistant human lung cancer cells and the associated molecular mechanism.

Experimental design

H1975 cell line was treated with Met and/or Gef to examine the inhibition of cell growth and potential mechanism of action by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), Ki67 incorporation assay, flow cytometry analysis, small interfering RNA technology, Western blot analysis and xenograft implantation.

Results

Insulin-like growth factor-1 receptor (IGF-1R) signaling pathway was markedly activated in EGFR-TKI primary resistant H1975 cells as compared to EGFR-TKI acquired resistance cells (PC-9GR, H1650-M3) and EGFR-TKI sensitivity cells (PC-9, HCC827). Inhibition of IGF-1R activity by AG-1024 (a small molecule of IGF-1R inhibitor), as well as downregulation of IGF-1R by siRNA, significantly enhanced the ability of Gef to suppress proliferation and induce apoptosis in H1975 cells via the inhibition of AKT activation and subsequent upregulation of Bcl-2-interacting mediator of cell death (BIM). Interestingly, the observation showed that Met combined with Gef treatment had similar tumor growth suppression effects in comparison with the addition of AG-1024 to therapy with Gef. A clear synergistic antiproliferative interaction between Met and Gef was observed with a combination index (CI) value of 0.65. Notably, IGF-1R silencing mediated by RNA interference (RNAi) attenuated anticancer effects of Met without obviously resensitizing H1975 cells to Gef. Finally, Met-based combinatorial therapy effectively blocked tumor growth in the xenograft with TKI primary resistant lung cancer cells.

Conclusion

Our findings demonstrated that Met combined with Gef would be a promising strategy to overcome EGFR-TKI primary resistance via suppressing IGF-1R signaling pathway in NSCLC.

Strong Programmed Death Ligand 1 Expression Predicts Poor Response and De Novo Resistance to EGFR Tyrosine Kinase Inhibitors Among NSCLC Patients With EGFR Mutation

INTRODUCTION

This study evaluated whether tumor expression of programmed death ligand 1 (PD-L1) could predict the response of EGFR-mutated NSCLC to EGFR tyrosine kinase inhibitor (TKI) therapy.

METHODS

We retrospectively evaluated patients who received EGFR-TKIs for advanced NSCLC at the Guangdong Lung Cancer Institute between April 2016 and September 2017 and were not enrolled in clinical studies. The patients' EGFR and PD-L1 statuses were simultaneously evaluated.

RESULTS

Among the 101 eligible patients, strong PD-L1 expression significantly decreased objective response rate, compared with weak or negative PD-L1 expression (35.7% versus 63.2% versus 67.3%, p = 0.002), and shortened progression-free survival (3.8 versus 6.0 versus 9.5 months, p < 0.001), regardless of EGFR mutation type (19del or L858R). Furthermore, positive PD-L1 expression was predominantly observed among patients with de novo resistance rather than acquired resistance to EGFR-TKIs (66.7% versus 30.2%, p = 0.009). Notably, we found a high proportion of PD-L1 and cluster of differentiation 8 (CD8) dual-positive cases among patients with de novo resistance (46.7%, 7 of 15). Finally, one patient with de novo resistance to EGFR-TKIs and PD-L1 and CD8 dual positivity experienced a favorable response to anti-programmed death 1 therapy.

CONCLUSIONS

This study revealed the adverse effects of PD-L1 expression on EGFR-TKI efficacy, especially in NSCLC patients with de novo resistance. The findings indicate the reshaping of an inflamed immune phenotype characterized by PD-L1 and CD8 dual positivity and suggest potential therapeutic sensitivity to programmed death 1 blockade.

Concomitant driver mutations in advanced EGFR-mutated non-small-cell lung cancer and their impact on erlotinib treatment

Background

Patients with EGFR-mutated non-small-cell lung cancer benefit from EGFR tyrosine kinase inhibitors (TKIs) like erlotinib. However, the efficacy may be impaired by driver mutations in other genes.

Methods

Five hundred and fourteen consecutive patients with NSCLC of all stages were tested for EGFR-mutations by cobas® EGFR Mutation Test. Fluorescent in situ hybridization (FISH) for MET-amplification, immunohistochemistry (IHC) for MET- and ALK-expression, and Next Generation Sequencing (NGS) for concomitant driver mutations were performed on EGFR-mutated tumor samples from erlotinib-treated patients.

Results

Thirty-six patients (7%) had EGFR-mutations, including 2 with intrinsic resistance mutation p.T790M together with the p.L858R sensitizing mutation and 1 harboring the p.G719C/S768I double-mutation. Twenty-three patients had either locally advanced or advanced disease and received first-line erlotinib-treatment. Concomitant driver mutations were found in 15/21 (71%) of NGS-analyzed TKI-treated NSCLCs, involving in 67% of cases TP53, in 13% CTNNB1, and in 7% KRAS, MET, SMAD4, PIK3CA, FGFR1, FGFR3, NRAS, DDR2, and ERBB4. No ALK-expression was found, whereas MET-overexpression and MET-amplification were observed in 5 and 4 patients, respectively. Objective responses occurred in 17/23 patients (74%), 4 did not respond (17%), and 2 harboring a SMAD4-mutation (p.R135^*(stop)) and a FGFR3-mutation (p.D785fs^*31), respectively, displayed mixed response with simultaneously progressing and responding tumors (8.7%). Thus, EGFR-mutated tumors harboring co-mutations were not less likely to respond.

Conclusion

Co-mutations in other cancer-driver genes (oncogenes or tumor suppressor genes) were frequent in EGFR-mutated NSCLCs and few cases harbored concomitant activating and resistance EGFR-mutations before TKI-treatment. Most co-mutations did not impact the response to first-line erlotinib-treatment, but may represent potential additional therapeutic targets.

A systematic review and meta-analysis of individual patient data on the impact of the BIM deletion polymorphism on treatment outcomes in epidermal growth factor receptor mutant lung cancer

BACKGROUND

A germline deletion in the BIM (BCL2L11) gene has been shown to impair the apoptotic response to tyrosine kinase inhibitors (TKIs) in vitro but its association with poor outcomes in TKI-treated non-small cell lung cancer (NSCLC) patients remains unclear. We conducted a systematic review and meta-analysis on both aggregate and individual patient data to address this issue.

RESULTS

In an aggregate data meta-analysis (n = 1429), the BIM deletion was associated with inferior PFS (HR = 1.51, 95%CI = 1.06-2.13, P = 0.02). Using individual patient data (n = 1200), we found a significant interaction between the deletion and ethnicity. Amongst non-Koreans, the deletion was an independent predictor of shorter PFS (Chinese: HR = 1.607, 95%CI = 1.251-2.065, P = 0.0002; Japanese: HR = 2.636, 95%CI = 1.603-4.335, P = 0.0001), and OS (HR = 1.457, 95% CI = 1.063-1.997, P = 0.019). In Kaplan-Meier analyses, the BIM deletion was associated with shorter survival in non-Koreans (PFS: 8.0 months v 11.1 months, P < 0.0005; OS: 25.7 v 30.0 months, P = 0.042). In Koreans, the BIM deletion was not predictive of PFS or OS.

MATERIALS AND METHODS

10 published and 3 unpublished studies that reported survival outcomes in NSCLC patients stratified according to BIM deletion were identified from PubMed and Embase. Summary risk estimates were calculated from aggregate patient data using a random-effects model. For individual patient data, Kaplan-Meier analyses were supported by multivariate Cox regression to estimate hazard ratios (HRs) for PFS and OS.

CONCLUSIONS

In selected populations, the BIM deletion is a significant predictor of shorter PFS and OS on EGFR-TKIs. Further studies to determine its effect on response to other BIM-dependent therapeutic agents are needed, so that alternative treatment strategies may be devised.

Analysis of progression-free survival of first-line tyrosine kinase inhibitors in patients with non-small cell lung cancer harboring leu858Arg or exon 19 deletions

Background

Gefitinib, erlotinib and afatinib provide remarkable response rates and progression-free survival compared to platinum-based chemotherapy in patients with non-small cell lung cancer harboring epidermal growth factor receptor-activating mutations, and are therefore standard first-line treatment in these patients. However, no study has compared these drugs regarding progression-free survival.

Materials and Methods

We conducted this retrospective study at a single medical center in Taiwan from February 16, 2011 to October 30, 2015. We used the Kaplan-Meier method to estimate survival, and multivariate Cox proportional hazard models to estimate adjusted hazard ratios and 95% confidence intervals.

Findings

Of the 1006 patients diagnosed with stage IIIb and IV non-small cell lung cancer in the study period, 448 (44.5%) had EGFR-activating mutations and received first-line therapy with gefitinib (n = 304, 67.6%), erlotinib (n = 63, 14.3%), or afatinib (n = 81, 18.1%). The median duration of follow-up for progression-free survival was 12.1 months in the gefitinib arm (Interquartile range [IQR]: 5.5–16.5), 11.2 months in the erlotinib arm (IQR: 4.9–16.7), and 10.3 months in the afatinib arm (IQR: 7.0–14.2). Progression-free survival was significantly longer in the patients who received afatinib or erlotinib compared to those who received gefitinib (log-rank test, p < 0.001), and the median progression-free survival was 11.4 months in the gefitinib group.

Interpretation

Afatinib and erlotinib provide significant benefits in progression-free survival compared to gefitinib in first-line treatment of patients with non-small-cell lung cancers harboring EGFR-activating mutations. Further clinical trials are warranted to validate these findings.

Concurrent gene alterations with EGFR mutation and treatment efficacy of EGFR-TKIs in Chinese patients with non-small cell lung cancer

PURPOSE

We investigated the frequency of concurrent genes in EGFR-mutant non-small cell lung cancer patients and determined its value in predicting the efficacy of EGFR-TKIs treatment.

METHODS

Three hundred and twenty patients, who harbored EGFR activating mutations and received EGFR-TKIs treatment, were examined for another eight genes including KRAS, NRAS, PIK3CA, BRAF, and HER2 mutations and ALK, ROS1, and RET fusion genes based on reverse transcription PCR. Progression-free survival and overall survival with EGFR-TKIs treatment were evaluated using Kaplan-Meier methods and compared between different patients using log-rank tests.

RESULTS

Twenty-one (6.6%) of 320 EGFR mutant samples with additional gene alterations were identified. The most common concurrent gene was PIK3CA mutation (n = 9), followed by EML4-ALK rearrangement (n = 6), HER2 mutation (n = 3), RET rearrangement (n = 1), ROS1 rearrangement (n = 1) and KRAS mutation (n = 1). Patients with single EGFR mutation had a significantly longer progression-free survival than those with concurrent genes (10.9 vs. 6.0 months, P = 0.002). Among the 21 cases, patients with PIK3CA mutation had the longest median progression-free survival (7.6 months), followed by ALK rearrangement (5.0 months) and other gene types (1.2 months). No overall survival difference was found between patients with single EGFR mutation and concurrent gene alterations (21.0 vs.17.6 months, P = 0.17).

CONCLUSION

We demonstrated that concurrent gene alterations occurred in some patients with EGFR mutations. Concurrent gene alterations decreased the efficacy of EGFR-TKIs.

Clinical Implications of the BIM Deletion Polymorphism in Advanced Lung Adenocarcinoma Treated With Gefitinib

BACKGROUND

Proapoptotic protein Bcl-2-like 11 (BIM) is a crucial tumor suppressor gene in lung cancer development. A 2903-bp genomic deletion polymorphism is present in BIM intron 2, which alters RNA splicing and impairs the generation of the death-inducing isoform of BIM and resistance to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). In the present study, we investigated the clinical implications of this genetic polymorphism in patients with advanced lung adenocarcinoma treated with gefitinib.

MATERIALS AND METHODS

After genotyping the BIM deletion polymorphism in 111 patients with stage IIIB or IV lung adenocarcinoma receiving gefitinib, the hazard ratio (HR) and 95% confidence interval (CI) for progression-free survival and overall survival were estimated using Cox proportional hazards models.

RESULTS

Possession of ≥ 1 deletion allele of the BIM polymorphism was observed in 18.02% of the patients. The BIM deletion polymorphism was an independent indicator of a shorter PFS (7.5 months vs. 11.3 months; HR, 2.38; 95% CI, 1.30-4.34; P = .005) and shorter OS (9.9 months vs. 27.5 months; HR, 2.53; 95% CI, 1.37-4.65; P = .003). Additionally, patients carrying the BIM deletion allele were more likely to experience acquired gefitinib-resistant disease.

CONCLUSION

Our results indicate that the BIM deletion polymorphism might be a promising germline biomarker for gefitinib treatment in Chinese patients with lung adenocarcinoma.

New insights in non-small-cell lung cancer: circulating tumor cells and cell-free DNA

Lung cancer is the second most frequent tumor and the leading cause of death by cancer in both men and women. Increasing knowledge about the cancer genome and tumor environment has led to a new setting in which morphological and molecular characterization is needed to treat patients in the most personalized way in order to achieve better outcomes. Since tumor products can be detected in body fluids, the liquid biopsy, particularly, peripheral blood, has emerged as a new source for lung cancer biomarker's analysis. A variety of tumor components can be used for this purpose. Among them, circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) should be especially considered. Different detection methods for both CTCs and ctDNA have been and are being developed to improve the sensitivity and specificity of these tests. This would lead to better characterization and would solve some clinical doubts at different disease evolution times, e.g., intratumoral or temporal heterogeneity, difficulty in the obtaining a tumor sample, etc., and would also avoid the side effects of very expensive and complicated tumor obtaining interventions. CTCs and ctDNA are useful in different lung cancer settings. Their value has been shown for the early diagnosis, prognosis, prediction of treatment efficacy, monitoring responses and early detection of lung cancer relapse. CTCs have still not been validated for use in clinical settings in non-small-cell lung cancer (NSCLC), while ctDNA has been approved by the Food and Drug Administration (FDA) and European Medical Association (EMA), and the main clinical guidelines used for detect different epidermal growth factor receptor (EGFR) mutations and the monitoring and treatment choice of mutated patients with tyrosine kinase inhibitors (TKIs). This review, describes how ctDNA seem to be winning the race against CTCs from the laboratory bench to clinical practice due to easier obtaining methods, manipulation and its implementation into clinical practice.