Clinical features ofBimdeletion polymorphism and its relation with crizotinib primary resistance in Chinese patients withALK/ROS1fusion-positive non-small cell lung cancer

Top 20 EGFR+ NSCLC Clinical and Translational Science Papers That Shaped the 20 Years Since the Discovery of Activating EGFR Mutations in NSCLC. An Editor-in-Chief Expert Panel Consensus Survey

The year 2024 is the 20th anniversary of the discovery of activating epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC). Since then, tremendous advances have been made in the treatment of NSCLC based on this discovery. Some of these studies have led to seismic changes in the concept of oncology research and spurred treatment advances beyond NSCLC, leading to a current true era of precision oncology for all solid tumors. We now routinely molecularly profile all tumor types and even plasma samples of patients with NSCLC for multiple actionable driver mutations, independent of patient clinical characteristics nor is profiling limited to the advanced incurable stage. We are increasingly monitoring treatment responses and detecting resistance to targeted therapy by using plasma genotyping. Furthermore, we are now profiling early-stage NSCLC for appropriate adjuvant targeted treatment leading to an eventual potential "cure" in early-stage EGFR+ NSCLC which have societal implication on implementing lung cancer screening in never-smokers as most EGFR+ NSCLC patients are never-smokers. All these advances were unfathomable in 2004 when the five papers that described "discoveries" of activating EGFR mutations (del19, L858R, exon 20 insertions, and "uncommon" mutations) were published. To commemorate this 20th anniversary, we assembled a global panel of thoracic medical oncology experts to select the top 20 papers (publications or congress presentation) from the 20 years since this seminal discovery with December 31, 2023 as the cutoff date for inclusion of papers to be voted on. Papers ranked 21 to 30 were considered "honorable mention" and also annotated. Our objective is that these 30 papers with their annotations about their impact and even all the ranked papers will serve as "syllabus" for the education of future thoracic oncology trainees. Finally, we mentioned potential practice-changing clinical trials to be reported. One of them, LAURA was published online on June 2, 2024 was not included in the list of papers to be voted on but will surely be highly ranked if this consensus survery is performed again on the 25th anniversay of the discovery EGFR mutations (i.e. top 25 papers on the 25 years since the discovery of activating EGFR mutations).

ALK inhibitors in cancer: mechanisms of resistance and therapeutic management strategies

Anaplastic lymphoma kinase (ALK) gene rearrangements have been identified as potent oncogenic drivers in several malignancies, including non-small cell lung cancer (NSCLC). The discovery of ALK inhibition using a tyrosine kinase inhibitor (TKI) has dramatically improved the outcomes of patients with ALK-mutated NSCLC. However, the emergence of intrinsic and acquired resistance inevitably occurs with ALK TKI use. This review describes the molecular mechanisms of ALK TKI resistance and discusses management strategies to overcome therapeutic resistance.

CD74/SLC34A2-ROS1 Fusion Variants Involving the Transmembrane Region Predict Poor Response to Crizotinib in NSCLC Independent of TP53 Mutations

INTRODUCTION

Variable partners and breakpoints have been reported in patients with ROS1-rearranged NSCLC. Here, we investigated the association of fusion partners and breakpoints with crizotinib efficacy in NSCLCs with common ROS1 fusions.

METHODS

DNA and RNA next-generation sequencing (NGS) and immunohistochemistry were performed to characterize ROS1 fusions.

RESULTS

Using DNA NGS, we identified ROS1 fusions in 210 cases, comprising 171 common (CD74/EZR/TPM3/SDC4/SLC34A2-ROS1) and 39 uncommon (variants identified in <5%) ROS1 fusion cases. DNA NGS detected variable ROS1 genomic breakpoints in common ROS1 fusions, whereas RNA NGS found ROS1 breakpoints mainly occurring in exons 32, 34 and 35, resulting in long (exon 32) and short (exon 34 or 35) ROS1 fusions. ROS1 immunohistochemistry revealed that membranous and cytoplasmic staining was predominant in long ROS1 fusions, whereas cytoplasmic staining was predominant in short ROS1 fusions (p = 0.006). For patients who received first-line crizotinib, median progression-free survival (mPFS) was lower in patients with long ROS1 fusions than those with short ROS1 fusions (8.0 versus 24.0 mo, p = 0.006). Moreover, mPFS for patients with and without TP53 mutations was 8.0 and 19.0 months, respectively (p = 0.159); mPFS for patients with and without BIM deletion polymorphism was 5.0 and 22.0 months, respectively (p = 0.003). When analyzing together with fusion partners, patients with long CD74/SLC34A2-ROS1 fusions were found to have shorter PFS than those with other ROS1, regardless of the presence or absence of TP53 mutations (p < 0.001 and p = 0.002, respectively).

CONCLUSIONS

Long CD74/SLC34A2-ROS1 fusions, which retain transmembrane regions in ROS1 and fusion partners, are associated with poor response to crizotinib independent of TP53 mutations.

c-Kit Receptors as a Therapeutic Target in Cancer: Current Insights

c-Kit is a type III receptor tyrosine kinase (RTK) that has an essential role in various biological functions including gametogenesis, melanogenesis, hematopoiesis, cell survival, and apoptosis. c-KIT aberrations, either overexpression or loss-of-function mutations, have been implicated in the pathogenesis and development of many cancers, including gastrointestinal stromal tumors, mastocytosis, acute myeloid leukemia, breast, thyroid, and colorectal cancer, making c-KIT an attractive molecular target for the treatment of cancers. Therefore, a lot of effort has been put into investigating the utility of tyrosine kinase inhibitors for the management of c-KIT mutated tumors. This review of the literature illustrates the role of c-KIT mutations in many cancers, aiming to provide insights into the role of TKIs as a therapeutic option for cancer patients with c-KIT aberrations. In conclusion, c-KIT is implicated in different types of cancer, and it could be a successful molecular target; however, proper detection of the underlying mutation type is required before starting the appropriate personalized therapy.

Therapeutical Options in ROS1-Rearranged Advanced Non Small Cell Lung Cancer

ROS proto-oncogene 1 (ROS1) rearrangements occur in 0.9-2.6% of patients with non small cell lung cancer (NSCLC), conferring sensitivity to treatment with specific tyrosine-kinase inhibitors (TKI). Crizotinib, a first-generation TKI, was the first target-therapy approved for the first-line treatment of ROS1-positive NSCLC. Recently, entrectinib, a multitarget inhibitor with an anti-ROS1 activity 40 times more potent than crizotinib and better activity on the central nervous system (CNS), received approval for treatment-naive patients. After a median time-to-progression of 5.5-20 months, resistance mechanisms can occur, leading to tumor progression. Therefore, newer generation TKI with greater potency and brain penetration have been developed and are currently under investigation. This review summarizes the current knowledge on clinicopathological characteristics of ROS1-positive NSCLC and its therapeutic options.

Molecular pathways, resistance mechanisms and targeted interventions in non-small-cell lung cancer

Lung cancer is the leading cause of cancer-related mortality worldwide. The discovery of tyrosine kinase inhibitors effectively targeting EGFR mutations in lung cancer patients in 2004 represented the beginning of the precision medicine era for this refractory disease. This great progress benefits from the identification of driver gene mutations, and after that, conventional and new technologies such as NGS further illustrated part of the complex molecular pathways of NSCLC. More targetable driver gene mutation identification in NSCLC patients greatly promoted the development of targeted therapy and provided great help for patient outcomes including significantly improved survival time and quality of life. Herein, we review the literature and ongoing clinical trials of NSCLC targeted therapy to address the molecular pathways and targeted intervention progress in NSCLC. In addition, the mutations in EGFR gene, ALK rearrangements, and KRAS mutations in the main sections, and the less common molecular alterations in MET, HER2, BRAF, ROS1, RET, and NTRK are discussed. The main resistance mechanisms of each targeted oncogene are highlighted to demonstrate the current dilemma of targeted therapy in NSCLC. Moreover, we discuss potential therapies to overcome the challenges of drug resistance. In this review, we manage to display the current landscape of targetable therapeutic patterns in NSCLC in this era of precision medicine.

Third-generation EGFR and ALK inhibitors: mechanisms of resistance and management

The discoveries of EGFR mutations and ALK rearrangements as actionable oncogenic drivers in non-small-cell lung cancer (NSCLC) has propelled a biomarker-directed treatment paradigm for patients with advanced-stage disease. Numerous EGFR and ALK tyrosine kinase inhibitors (TKIs) with demonstrated efficacy in patients with EGFR-mutant and ALK-rearranged NSCLCs have been developed, culminating in the availability of the highly effective third-generation TKIs osimertinib and lorlatinib, respectively. Despite their marked efficacy, resistance to these agents remains an unsolved fundamental challenge. Both 'on-target' mechanisms (largely mediated by acquired resistance mutations in the kinase domains of EGFR or ALK) and 'off-target' mechanisms of resistance (mediated by non-target kinase alterations such as bypass signalling activation or phenotypic transformation) have been identified in patients with disease progression on osimertinib or lorlatinib. A growing understanding of the biology and spectrum of these mechanisms of resistance has already begun to inform the development of more effective therapeutic strategies. In this Review, we discuss the development of third-generation EGFR and ALK inhibitors, predominant mechanisms of resistance, and approaches to tackling resistance in the clinic, ranging from novel fourth-generation TKIs to combination regimens and other investigational therapies.

Real-World Management and Outcomes of Crizotinib-Treated ROS1-Rearranged NSCLC: A Retrospective Canadian Cohort

The use, safety and effectiveness of crizotinib as part of the management of ROS1-rearranged NSCLC patients in a real-world Canadian clinical cohort was the focus of this retrospective review. Twenty-one ROS1-rearranged patients with advanced/metastatic disease receiving crizotinib between 2014-2020 were identified; crizotinib demonstrated tolerability and effectiveness in this population where outcomes were similar to those described in other crizotinib-treated real-world cohorts, but lower than those of the PROFILE 1001 clinical trial population. Systemic anti-cancer therapy prior to crizotinib initiation occurred in half of the study cohort, with platin-pemetrexed and immune checkpoint inhibitors being most common. Platin-pemetrexed showed good effectiveness in this cohort, but despite high prevalence of upregulated PD-L1 expression, immune checkpoint inhibitors showed poor effectiveness in his cohort. Among all systemic therapies received, crizotinib showed the most effective disease control, although longer intervals between diagnosis and crizotinib initiation were more common among those showing a lack of clinical response to crizotinib, and patients with brain metastases at the time of crizotinib initiation also showed increased diagnosis to crizotinib initiation intervals and decreased clinical response to crizotinib. This study reveals crizotinib has clinical benefit, but timely identification of ROS1-rearrangements and initiation targeted therapies appears important to maximize outcome in this population.

Review of Therapeutic Strategies for Anaplastic Lymphoma Kinase-Rearranged Non-Small Cell Lung Cancer

Simple Summary

Anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer (NSCLC) was first reported in 2007. Following the development of crizotinib as a tyrosine kinase inhibitor (TKI) targeting ALK, the treatment of advanced NSCLC with ALK-rearrangements has made remarkable progress. Currently, there are five ALK-TKIs approved by the FDA, and the development of new agents, including fourth-generation TKI, is ongoing. Clinical trials with angiogenesis inhibitors and immune checkpoint inhibitors are also underway, and further progress in the treatment of ALK-rearranged advanced NSCLC is expected. The purpose of this manuscript is to provide information on the recent clinical trials of ALK-TKIs, angiogenesis inhibitors, immune checkpoint inhibitors, and chemotherapy, to describe tissue and liquid biopsy as a method to investigate the mechanisms of resistance against ALK-TKIs and suggest a proposed treatment algorithm.

Abstract

Non-small cell lung cancer (NSCLC) with anaplastic lymphoma kinase rearrangement (ALK) was first reported in 2007. ALK-rearranged NSCLC accounts for about 3–8% of NSCLC. The first-line therapy for ALK-rearranged advanced NSCLC is tyrosine kinase inhibitors (TKI) targeting ALK. Following the development of crizotinib, the first ALK-TKI, patient prognosis has been greatly improved. Currently, five TKIs are approved by the FDA. In addition, clinical trials of the novel TKI, ensartinib, and fourth-generation ALK-TKI for compound ALK mutation are ongoing. Treatment with angiogenesis inhibitors and immune checkpoint inhibitors is also being studied. However, as the disease progresses, cancers tend to develop resistance mechanisms. In addition to ALK mutations, other mechanisms, including the activation of bypass signaling pathways and histological transformation, cause resistance, and the identification of these mechanisms is important in selecting subsequent therapy. Studies on tissue and liquid biopsy have been reported and are expected to be useful tools for identifying resistance mechanisms. The purpose of this manuscript is to provide information on the recent clinical trials of ALK-TKIs, angiogenesis inhibitors, immune checkpoint inhibitors, and chemotherapy to describe tissue and liquid biopsy as a method to investigate the mechanisms of resistance against ALK-TKIs and suggest a proposed treatment algorithm.

Prognostic Markers of Survival among Japanese Patients with Anaplastic Lymphoma Kinase-Positive Non-Small-Cell Lung Cancer Receiving First-Line Alectinib

The prognoses of patients with non-small-cell lung cancer (NSCLC) harboring anaplastic lymphoma kinase (ALK) gene rearrangement have dramatically improved with the use of ALK tyrosine kinase inhibitors. Although immunological and nutritional markers have been investigated to predict outcomes in patients with several cancers, their usefulness in targeted therapies is scarce, and their significance has never been reported in patients receiving first-line treatment with alectinib. Meanwhile, neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio (PLR) has been investigated during crizotinib treatment. This multicenter retrospective study evaluated 42 consecutive Japanese patients with ALK-positive NSCLC who received first-line treatment with alectinib. Immunological and nutritional markers were evaluated at baseline and 3 weeks after alectinib introduction, and their significance in predicting progression-free survival (PFS) was explored. PFS duration was significantly associated with baseline PLR (hazard ratio (HR): 2.49, p = 0.0473), systemic immune-inflammation index (SII; HR: 2.65, p = 0.0337), prognostic nutrition index (PNI; HR: 4.15, p = 0.00185), and the 3-week values for SII (HR: 2.85, p = 0.0473) and PNI (HR: 3.04, p = 0.0125). Immunological and nutritional markers could be useful in predicting the outcomes of first-line treatment with alectinib. Since PLR and SII consist of platelet counts, platelet count could be an important constituent of these markers.

The Resistance Mechanisms and Treatment Strategies for ALK-Rearranged Non-Small Cell Lung Cancer

Anaplastic lymphoma kinase (ALK) is a validated molecular target for non-small-cell lung cancer (NSCLC). The use of tyrosine kinase inhibitors (TKIs) has led to significantly improved survival benefits. However, the clinical benefits of targeting ALK using TKIs are limited due to the emergence of drug resistance. The landscape of resistance mechanisms and treatment decisions has become increasingly complex. Therefore, continued research into new drugs and combinatorial therapies is required to improve outcomes in NSCLC. In this review, we explore the resistance mechanisms of ALK TKIs in advanced NSCLC in order to provide a theoretical basis and research ideas for solving the problem of ALK drug resistance.

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.

Exon 20 YVMA insertion is associated with high incidence of brain metastasis and inferior outcome of chemotherapy in advanced non-small cell lung cancer patients with HER2 kinase domain mutations

BACKGROUND

Chemotherapy remains the standard care for HER2 mutated advanced non-small cell lung cancer (NSCLC) even though several targeted drugs showed promising results in preliminary stages. This study aimed to investigate the association of mutation variants with clinical features and the efficacy of chemotherapy in patients with HER2 mutated advanced NSCLC.

METHODS

ARMS-PCR was used to identify HER2 mutation in patients without common oncogenic alterations. Patients with detailed information were further enrolled for analysis of clinical features and efficacy of first line chemotherapy. Survival data was analyzed by Kaplan-Meier method and compared by log-rank test. Brain metastasis incidence was analyzed and compared by Gray's test.

RESULTS

YVMA insertion accounted for the majority (68.4%, 67/98) of HER2 mutation, and associated with significantly higher incidence of baseline extrathoracic metastasis (P=0.009), notably brain metastasis (P=0.004). Among 82 patients those received first line chemotherapy, YVMA insertion remarkably associated with inferior treatment outcomes, namely, a significantly shorter median progression free survival (PFS) and lower objective response rate (ORR) both in total patients (PFS: 5.2 vs. 7.7 m, P=0.038; ORR: 30.9% vs. 51.9%, P=0.09) and pemetrexed subgroup (PFS: 5.2 vs. 6.5 m, P=0.022; ORR: 31.8% vs. 60.0%, P=0.054). Multivariate analysis further established YVMA insertion as prognostic factor of worse PFS both for total patients (HR =1.578, 95% CI, 0.956-2.606) and patients received pemetrexed-based chemotherapy (HR =1.789, 95% CI, 1.013-3.160). In addition, YVMA insertion associated with higher incidence of lifetime brain metastasis (P=0.002) compared by Gray's test, with estimated 12-month brain metastasis incidence as 40.2% compared with 3.6% in the non-YVMA group.

CONCLUSIONS

YVMA insertion is associated with a higher incidence of brain metastasis, and inferior outcomes to chemotherapy than non-YVMA variants in patients with advanced NSCLC and HER2 kinase domain mutations, which emphasized the unmet need of more potent anti-cancer therapies with high blood-brain barrier (BBB) penetration capacity for patients with YVMA insertion.

Clinical implications of germline BCL2L11 deletion polymorphism in pretreated advanced NSCLC patients with osimertinib therapy

INTRODUCTION

B-cell lymphoma 2-like 11 (BCL-2-like 11, BCL2L11, also known as BIM) deletion polymorphism (BIM-del) has been associated with resistance to first-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), and is a poor prognostic factor for EGFR-mutant non-small-cell lung cancer (NSCLC) patients. Nevertheless, the impact of BIM-del in advanced NSCLC patients treated with the third-generation EGFR-TKI osimertinib remains undetermined. This study aims to evaluate the relationship between BIM-del and therapeutic efficacy of osimertinib in pretreated NSCLC patients.

METHODS

Patients subjected to EGFR T790 M detection and prior osimertinib treatment between December 2015 and December 2019 in our hospital were enrolled in this study. Peripheral blood samples from these patients were collected to detect BIM-del by polymerase chain reaction. Cox proportional hazards models were used to analyze the clinical outcomes of patients with and without BIM-del.

RESULTS

In total, 152 Chinese Han NSCLC patients-including 143 T790M-positive and nine T790M-negative patients-were enrolled. BIM-del was detected in only 17.5 % of T790M-positive patients (25/143). The majority of patients were aged <65 years (81.8 %, 117/143), were female (58.7 %, 84/143), were non-smokers (82.5 %, 118/143), had Eastern Cooperative Oncology Group (ECOG) performance status (PS) 0-1 (88.8 %, 129/143), and exhibited metastases in the central nervous system (CNS) (54.5 %, 78/143). There were no associations between the BIM-del and clinical characteristics (including age, sex, histology, smoking status, stage, ECOG PS score, and CNS metastases). Patients with BIM-del had a poorer objective response rate than those without (28.0 % versus 52.5 %, p = 0.026). Besides, BIM-del was associated with a significantly shorter progression-free survival (PFS) and a moderately shorter overall survival (OS) (8.3 versus 10.5 months, p = 0.031 and 15.9 versus 25.2 months, p = 0.1, respectively). Multivariate analysis indicated that BIM-del was an independent prognostic factor for PFS but not for OS in EGFR T790 M NSCLC patients.

CONCLUSIONS

BIM-del is associated with poor clinical responses and outcomes, and might be a negative predictive and prognostic biomarker in EGFR T790 M NSCLC patients with osimertinib treatment.

Overcoming TKI resistance in fusion-driven NSCLC: new generation inhibitors and rationale for combination strategies

During the last several years, multiple gene rearrangements with oncogenic potential have been described in NSCLC, identifying specific clinic-pathological subgroups of patients that benefit from a targeted therapeutic approach, including anaplastic lymphoma kinase (ALK), c-ros protooncogene 1 (ROS1) and, more recently, REarranged during Transfection (RET) and neurotrophic tyrosine receptor kinases (NTRK) genes. Despite initial impressive antitumor activity, the use of targeted therapies in oncogene-addicted NSCLC subgroups is invariably associated with the development of acquired resistance through multiple mechanisms that can include both on-target and off-target mechanisms. However, the process of acquired resistance is a rapidly evolving clinical scenario that constantly evolves under the selective pressure of tyrosine kinase inhibitors. The development of increasingly higher selective and potent inhibitors, traditionally used to overcome resistance to first generation inhibitors, is associated with the development of novel mechanisms of resistance that encompass complex resistance mutations, highly recalcitrant to available TKIs, and bypass track mechanisms. Herein, we provide a comprehensive overview on the therapeutic strategies for overcoming acquired resistance to tyrosine kinase inhibitors (TKIs) targeting the most well-established oncogenic gene fusions in advanced NSCLC, including ALK, ROS1, RET, and NTRK rearrangements.

[Advances in Drug Resistance Mechanisms and Prognostic Markers of Targeted Therapy in ALK-positive Non-small Cell Lung Cancer]

棘皮动物微管相关类蛋白4-间变性淋巴瘤激酶(echinoderm microtubule-associated protein like 4-anaplastic lymphoma kinase, EML4-ALK)融合占非小细胞肺癌(non-small cell lung cancer, NSCLC)患者的3%-5%。随着对该驱动基因的深入研究，以Crizotinib为代表的ALK抑制剂逐渐被开发并应用于临床。然而，不同患者对ALK靶向治疗的反应存在差异，且多数ALK靶向治疗患者最终会不可避免地出现耐药，导致肿瘤进展。利用预后标志物监测患者疗效及时改变治疗方案，以及根据耐药机制选择个体化的后续治疗，可以有效地改善患者的预后。本文将对ALK抑制剂的耐药机制以及相关的预后标志物展开综述，探讨ALK靶向治疗疗效预测以及耐药患者后续治疗方案的选择。

Impact of ALK variants on brain metastasis and treatment response in advanced NSCLC patients with oncogenic ALK fusion

Background

To investigate the impact of ALK variants on the features of brain metastases (BM), the outcome of chemotherapy and targeted therapy using crizotinib, as well as the progression pattern in patients with ALK fusion.

Methods

Patients with ALK fusion were retrospectively collected from January 2013 to July 2017 in Shanghai Pulmonary Hospital. ALK rearrangements were identified via ARMS-PCR. ALK variants were identified via Sanger Sequencing.

Results

A total of 135 patients and 41 with brain metastasis were identified. Radiological features showed that the patients with ALK variant 1 had a larger BM size compared with patients with ALK non-variant 1 (median tumor size: 16.89 vs. 11.01 mm, P=0.031). Similar time to treatment failure (TTF) was observed in patients with ALK variant 1 and non-variant 1 who received first-line crizotinib (median TTF: 15.7 vs. 13.8 months, HR =0.75, P=0.34). Patients with ALK variant 1 who had baseline BM had significantly shorter TTF than non-variant 1 with baseline BM when treated with first-line crizotinib (median TTF: 9.1 vs. 14.9 months, HR =2.68, P=0.037). In patients treated with chemotherapy, ALK variant 1 was associated with inferior TTF (median TTF: 5.6 vs. 8.1 months, HR =1.66, P=0.039). Progression pattern was similar between ALK variant 1 and non-variant 1.

Conclusions

Patients with ALK variant 1 and baseline BM had inferior TTF on first-line crizotinib treatment and presented with more aggressive radiological features. Patients with ALK non-variant 1 had better clinical outcome on first-line chemotherapy.

Targeting apoptosis in cancer therapy

For over three decades, a mainstay and goal of clinical oncology has been the development of therapies promoting the effective elimination of cancer cells by apoptosis. This programmed cell death process is mediated by several signalling pathways (referred to as intrinsic and extrinsic) triggered by multiple factors, including cellular stress, DNA damage and immune surveillance. The interaction of apoptosis pathways with other signalling mechanisms can also affect cell death. The clinical translation of effective pro-apoptotic agents involves drug discovery studies (addressing the bioavailability, stability, tumour penetration, toxicity profile in non-malignant tissues, drug interactions and off-target effects) as well as an understanding of tumour biology (including heterogeneity and evolution of resistant clones). While tumour cell death can result in response to therapy, the selection, growth and dissemination of resistant cells can ultimately be fatal. In this Review, we present the main apoptosis pathways and other signalling pathways that interact with them, and discuss actionable molecular targets, therapeutic agents in clinical translation and known mechanisms of resistance to these agents.

A strategy for preparing non-fluorescent graphene oxide quantum dots as fluorescence quenchers in quantitative real-time PCR

In recent years, graphene oxide quantum dots (GOQDs) have emerged as novel nanomaterials for optical sensing, bioimaging, clinical testing, and environmental testing. However, GOQDs demonstrate unique photoluminescence properties, with GOQDs having quantum limitations and edge effects that often affect the accuracy of the test results in the sensory field. Herein, GOQDs with a large content of hydroxyl groups and low fluorescence intensity were first prepared via an improved Fenton reaction in this study, which introduces a large amount of epoxy groups to break the C-C bonds. The synthesized GOQDs show no significant variation in the fluorescence intensity upon ultraviolet and visible light excitations. We further utilized the GOQDs as fluorescence quenchers for different fluorescent dyes in real-time fluorescence quantitative polymerase chain reaction (qRT-PCR), and verified that the addition of GOQDs (5.3 μg ml-1) into a qRT-PCR system could reduce the background fluorescence intensity of the reaction by fluorescence resonance energy transfer (FRET) during its initial stage and its non-specific amplification, and improve its specificity. In addition, the qRT-PCR method could detect two different lengths of DNA sequences with a high specificity in the 104 to 1010 copies per μl range. It is of paramount importance to carry out further investigations to establish an efficient, sensitive, and specific RT-PCR method based on the use of GOQD nanomaterials as fluorescence quenchers.

Uncommon EGFR mutations associate with lower incidence of T790M mutation after EGFR-TKI treatment in patients with advanced NSCLC

OBJECTIVES

Advanced non-small cell lung cancer (NSCLC) patients harboring non-resistant uncommon epidermal growth factor receptor (EGFR) mutations have stepped into the era of targeted therapy. This study aimed to investigate the incidence of acquired T790M mutation and their outcome to subsequent osimertinib in patients of advanced NSCLC harboring uncommon EGFR mutations.

PATIENTS AND METHODS

Patients with EGFR mutation and performed re-biopsy after progression on prior EGFR-tyrosine kinase inhibitors (TKIs) were reviewed and analyzed. Those with T790M mutation and received subsequent osimertinib treatment were further collected for survival analysis.

RESULTS

Finally, 754 patients, including 48 with uncommon mutation, 362 with 19del and 344 with L858R were enrolled. T790M mutation was identified in 341 patients (341/754, 45.2 %). The incidence of T790M mutation was 27.1 % in patients harboring uncommon mutations, significantly lower than 55.2 % and 37.2 % of 19del and L858R (p < 0.001). Logistic regression analysis further found uncommon mutation associated with significantly lower probability of developing T790M (odds ratio [OR] = 0.32, 95 % confidence interval [CI] 0.16-0.64). Among 236 patients received subsequent osimertinib treatment (including 12 uncommon mutation, 145 19del and 79 L858R), patients harboring uncommon mutations showed significantly shorter progression free survival (PFS) (median: 4.6 vs. 11.6 vs. 12.1 months, p < 0.001) and overall survival (OS) (median: 8.1 vs. 35.4 vs. 24.9 months, p = 0.001) compared with 19del and L858R, also associated with numerically lower objective response rate (ORR) (p = 0.085) and lower disease control rate (DCR) (p = 0.074). Multivariate analysis further found that uncommon mutation was the only one significantly associated with both PFS (hazard ratio [HR] = 3.44, 95 %CI 1.79-6.58) and OS (HR = 3.64, 95 %CI 1.66-7.99).

CONCLUSIONS

Uncommon EGFR mutation showed a significantly lower incidence of acquired T790M mutation and benefited significantly less from subsequent osimertinib treatment than common EGFR mutations in patients with advanced NSCLC.

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.

High feasibility of cytological specimens for detection of ROS1 fusion by reverse transcriptase PCR in Chinese patients with advanced non-small-cell lung cancer

Purpose

Our previous study demonstrated that cytological specimens can be used as alternative samples for detecting anaplastic lymphoma kinase (ALK) fusion with the method of reverse transcriptase PCR (RT-PCR) in patients with advanced non-small-cell lung cancer (NSCLC). The current study aimed to investigate the feasibility of cytological specimens for ROS proto-oncogene 1, receptor tyrosine kinase (ROS1) fusion detection by RT-PCR in advanced NSCLC patients.

Patients and methods

A total of 2,538 patients with advanced NSCLC, including 2,101 patients with cytological specimens and 437 patients with tumor tissues, were included in this study. All patients were screened for ROS1 fusion status by RT-PCR. The efficacy of crizotinib treatment was evaluated in ROS1 fusion-positive NSCLC patients.

Results

Among 2,101 patients with cytological specimens, the average concentration of RNA acquired from cytological specimens was 47.68 ng/μL (95% CI, 43.24–52.62), which was lower than the average of 66.54 ng/μL (95% CI, 57.18–76.60, P=0.001) obtained from 437 tumor tissues. Fifty-five patients harbored ROS1 fusion gene that was detected by RT-PCR, and 14 of them were treated with crizotinib. The incidence of ROS1 fusion was 1.95% (41/2,101) in 2,101 patients with cytological specimens, similar to the rate of 3.20% (14/437, P=0.102) for the 437 patients with tumor tissue. Regarding crizotinib treatment, no statistically significant differences were observed in the objective response rate (ORR) (81.8% vs 100%, P=0.604) between the cytological and tissue subgroups of ROS1-positive patients.

Conclusion

This study shows that cytological specimens can be utilized as alternative samples for ROS1 fusion detection by RT-PCR in advanced NSCLC patients.

Clinical features and outcomes of ALK rearranged non-small cell lung cancer with primary resistance to crizotinib

Background

Crizotinib is associated with a favorable survival benefit in patients with ALK‐positive non‐small cell lung cancer (NSCLC); however, a subset of patients harboring ALK rearrangement shows a poor response.

Methods

We collected the clinical features and survival outcomes of 28 primary‐resistant responders (PRR) with progression‐free survival (PFS) of < 3 months on crizotinib and compared these with 78 long‐term responders (LTR) that achieved > 24 months PFS (control).

Results

Primary resistance was observed in 6.5% of the patients. The median PFS of the PRR and LTR groups was 1.2 months (95% confidence interval [CI] 0.70–1.73) and 47.0 months (95% CI 34.39–59.64), respectively. A better Eastern Cooperative Oncology Group performance status score was significantly associated with longer PFS (odds ratio 0.06, 95% CI 0.01–0.33; P = 0.001). The median overall survival (OS) of the PRR group was 8.4 months (95% CI 3.47–13.42) and crizotinib as first‐line treatment was an independent predictive factor for survival outcome (P = 0.005). Patients administered ALK‐tyrosine kinase inhibitors after crizotinib progression had significantly longer survival than the PRR group treated with best supportive care (P = 0.007), but no significant difference was found between ALK‐tyrosine kinase inhibitor treatment and single chemotherapy (P = 0.944).

Conclusion

Patients with primary resistance to crizotinib displayed unfavorable survival outcomes and the underlying mechanism cannot be identified in clinical features. Nevertheless, next‐generation ALK inhibitors and chemotherapy after crizotinib progression could confer a therapeutic and survival benefit in this population.

Predictive and prognostic value of phosphorylated c-KIT and PDGFRA in advanced non-small cell lung cancer harboring ALK fusion

Secondary KIT gene amplification leads to tyrosine kinase inhibitor resistance in anaplastic lymphoma kinase (ALK) fusion-positive advanced non-small cell lung cancer (NSCLC). The presence of the 4q12 amplicon causes the activation of downstream mast/stem cell growth factor receptor Kit (c-Kit) or platelet-derived growth factor receptor α (PDGFRA) signaling pathways. Therefore, in the present study, the association between the functional proteins phosphorylated c-Kit (p-c-Kit) and phosphorylated PDGFRA (p-PDGFRA) and the prognosis of ALK fusion NSCLC was investigated. Advanced stage NSCLC samples with ALK fusion were tested for their p-c-Kit and p-PDGFRA content by immunohistochemical staining, and for its association with crizotinib efficacy and the survival of the patients. Of 64 eligible ALK-positive patients with NSCLC, 30 (46.9%) were p-c-Kit-positive and 10 (15.7%) were p-PDGFRA-positive. Brain metastases were more common in ALK-positive cases that were p-PDGFRA-positive compared with those who were p-PDGFRA-negative. ALK-positive patients treated with crizotinib, who exhibited high levels of p-c-Kit had significantly lower progression-free survival times than those with low levels. In addition, the patients with high levels of p-c-Kit exhibited lower overall survival times than those with low levels. Furthermore, multivariate analysis indicated that high levels of p-c-Kit in patients with ALK fusion was the only significant predictive factor for crizotinib efficacy and was a prognostic factor for poor overall survival time. However, no statistically significant difference was observed in the survival of patients with different p-PDGFRA levels. p-PDGFRA was more frequently expressed in the ALK-positive cases with brain metastasis. c-Kit signaling activation may be associated with poor efficacy of crizotinib and poor prognosis in advanced ALK fusion NSCLC.

The therapeutic role of inhibition of miR-328 on pulmonary carcinoma induced by chlamydia pneumoniae through targeting histone H2AX

Lung cancer represents a major healthy concern due to high incidence and morality. Increasing evidences showed critical regulatory role of microRNA (miR) in cell growth, differentiation and apoptosis. It has been indicated that the level of miR-328 is abnormally up regulated in lung cancer cell line, which is correlated with cell apoptosis. An in vitro lung cancer model was established through induction of chlamydia pneumonia. Western blot and real-time quantitative PCR were used to measure miR-328 level and its effects on histone H2AX expression. Bioinformatics analysis and luciferase reporter gene assay were to determine if H2AX was the direct target of miR-328. TUNEL assay, AV-PI staining and Caspase-3 activity assay measured the effect of the decrease of miR-328 on lung cancer cell apoptosis at both in vivo and in vitro level. Bioinformatics analysis predicted histone H2AX as the target of miR-328 during the regulation of lung cancer. Both in vivo and in vitro knockdown of miR-328 up-regulated H2AX expression and elevated TUNEL-positive cell number. In vivo down-regulation of miR-328 decreased incidence of lung cancer induced by chlamydia pneumoniae, suppressed tumor volume, increased caspase 3 activity, and facilitated tumor cell apoptosis. Histone protein H2AX serves as the target of miR-328 and participates in lung cancer regulation. Suppression of miR-328 level promotes lung cancer tissue apoptosis, which provides novel target for lung cancer therapy.

Afatinib reverses ceritinib resistance (CR) in ALK/ROS1-positive non-small-cell lung cancer cell (NSCLC) via suppression of NRG1 pathway

BACKGROUND

Lung cancer (LC) is the most prevalent malignancy worldwide, and non-small-cell LC (NSCLC) cell is associated with high mortality. As a member of the second generation of anaplastic lymphoma kinase (ALK) suppressors, ceritinib has considerable therapeutic effects for ALK and c-ros oncogene 1 (ROS1)-positive NSCLC cell. Nevertheless, patients inevitably develop resistance to the drug. Our research focused on the exploration of whether afatinib was able to counteract ceritinib resistance (CR) in NSCLC cells with positive ALK or ROS1.

MATERIALS AND METHODS

Acquired CR cell sublines (HCC78R and H1299R) were induced by stepwise escalation of ceritinib exposure. MTT assay was used to validate cell proliferation. Fluorescence assay was performed for apoptosis analysis. Quantitative real-time PCR and Western blot assays were used to assess the alterations of signaling pathway-related mRNA and proteins, respectively.

RESULTS

We found that prolonged treatment of HCC78 and H1299 with ceritinib brought about 10 times weaker ceritinib sensitivity (CS) in comparison with parent cells. Additionally, the results showed that afatinib efficiently promoted CS, which was evidenced as reduced proliferation and cell death promotion, in NSCLC cells, irrespective of their previous sensitivity or resistance to ceritinib. Moreover, afatinib decreased neuregulin-1 (NRG1) signaling stimulation in CR as well as CS cells. Furthermore, supplementing NRG1 in H1299 and HCC78 cells triggered CR, which was attenuated by afatinib.

CONCLUSION

These results demonstrated that afatinib overcame CR in NSCLC cells with positive ALK or ROS1 by inhibiting the NRG1 signaling pathway, which might be a promising therapeutic approach.

TP53 mutations predict for poor survival in ALK rearrangement lung adenocarcinoma patients treated with crizotinib

Background

Advanced non-small cell lung cancer (NSCLC) patients who harbor anaplastic lymphoma kinase (ALK) rearrangement are sensitive to an ALK inhibitor (crizotinib), but not all ALK-positive patients benefit equally from crizotinib treatment. We analyze the impact of TP53 mutations on response to crizotinib in patients with ALK rearrangement NSCLC.

Methods

Sixty-six ALK rearrangement NSCLC patients receiving crizotinib were analyzed. 21 cases were detected successfully by the next generation sequencing validation FFPE before crizotinib. TP53 mutations were evaluated in 8 patients in relation to disease control rate (DCR), objective response rate (ORR), progression-free survival (PFS) and overall survival (OS).

Results

TP53 mutations were observed in 2 (25.00%), 1 (12.50%), 1 (12.50%) and 4 (50.00%) patients in exons 5, 6, 7 and 8, respectively. The majority of patients were male (75.00%, 6/8), less than 65 years old (62.50%, 5/8) and never smokers (75.00%, 6/8). ORR and DCR for crizotinib in the entire case series were 61.90% and 71.43%, respectively. Statistically significant difference was observed in terms of PFS and OS between TP53 gene wild group and mutation group patients (P=0.038, P=0.021, respectively).

Conclusions

TP53 mutations reduce responsiveness to crizotinib and worsen prognosis in ALK rearrangement NSCLC patients.

EGFR-TKIs plus chemotherapy demonstrated superior efficacy than EGFR-TKIs alone as first-line setting in advanced NSCLC patients with EGFR mutation and BIM deletion polymorphism

BACKGROUND

Non-small-cell lung cancer (NSCLC) patients with both epidermal growth factor receptor (EGFR) positive mutation and B-cell chronic lymphocytic leukemia/lymphoma-like 11 (BIM) deletion polymorphism had a poor clinical response to EGFR-tyrosine kinase inhibitors (TKIs). The current study aimed to investigate the clinical efficacy and tolerability of EGFR-TKIs plus chemotherapy versus EGFR-TKIs alone as first-line treatment in advanced NSCLC patients with EGFR mutations and BIM deletion polymorphism.

METHODS

A retrospective, non-randomized analysis was conducted. BIM deletion polymorphism was detected using polymerase chain reaction (PCR) analysis and direct sequencing of DNA from peripheral blood cells. Clinical characteristics, overall survival (OS), progress-free-survival (PFS), objective response rate (ORR) and treatment-related adverse events were compared between EGFR-TKIs alone versus EGFR-TKIs plus chemotherapy group.

RESULTS

65 patients were enrolled. 36 of them received EGFR-TKIs and 29 received EGFR-TKIs plus chemotherapy. EGFR-TKIs plus chemotherapy had significantly higher ORR than TKIs alone (65.5% vs. 38.9%, P = 0.046). Median PFS was significantly longer in EGFR-TKIs plus chemotherapy group than in TKIs group (7.2 vs 4.7 m; P = 0.008). Median OS was numerically longer in EGFR-TKIs plus chemotherapy group than in TKIs alone (18.5 vs 14.2 m; P = 0.107). EGFR-TKIs plus chemotherapy was associated with more grade 3 or 4 hematological toxic effects than EGFR-TKIs alone.

CONCLUSION

EGFR-TKIs plus chemotherapy conferred a significantly higher ORR, prolonged PFS and numerically longer OS in advanced NSCLC patients with EGFR mutation and BIM deletion polymorphism. Further prospective studies are needed to validate these findings.

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.

Understanding and targeting resistance mechanisms in NSCLC

The expanding spectrum of both established and candidate oncogenic driver mutations identified in non-small-cell lung cancer (NSCLC), coupled with the increasing number of clinically available signal transduction pathway inhibitors targeting these driver mutations, offers a tremendous opportunity to enhance patient outcomes. Despite these molecular advances, advanced-stage NSCLC remains largely incurable due to therapeutic resistance. In this Review, we discuss alterations in the targeted oncogene ('on-target' resistance) and in other downstream and parallel pathways ('off-target' resistance) leading to resistance to targeted therapies in NSCLC, and we provide an overview of the current understanding of the bidirectional interactions with the tumour microenvironment that promote therapeutic resistance. We highlight common mechanistic themes underpinning resistance to targeted therapies that are shared by NSCLC subtypes, including those with oncogenic alterations in epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), ROS1 proto-oncogene receptor tyrosine kinase (ROS1), serine/threonine-protein kinase b-raf (BRAF) and other less established oncoproteins. Finally, we discuss how understanding these themes can inform therapeutic strategies, including combination therapy approaches, and overcome the challenge of tumour heterogeneity.