Epidermal Growth Factor Receptor In Non-small Cell Lung Cancer Research Articles

The suppression of the SPHK1/S1P/S1PR3 signaling pathway diminishes EGFR activation and increases the sensitivity of non-small cell lung cancer to gefitinib.

Non-small-cell lung cancer (NSCLC) represents a predominant histological subtype of lung cancer, characterized by high incidence and mortality rates. Despite significant advancements in therapeutic strategies and a deeper understanding of targeted therapies in recent years, tumor resistance remains an inevitable challenge, leading to poor prognostic outcomes. Several studies have indicated that sphingosine kinase 1 (SPHK1) plays a regulatory role in epidermal growth factor receptor (EGFR) signaling, and its elevated expression may be associated with resistance to EGFR tyrosine kinase inhibitors (EGFR-TKIs). Furthermore, the catalytic product of SPHK1, sphingosine 1-phosphate (S1P), along with its receptor, sphingosine 1-phosphate receptor 3 (S1PR3), plays a regulatory role in the function of the EGFR. However, the specific effects of the SPHK1/S1P/S1PR3 axis on EGFR in NSCLC, as well as the combined effects of SPHK1/S1P/S1PR3 inhibitors with the EGFR-TKI gefitinib, remain to be elucidated. In the present study, we investigated the correlation between SPHK1 expression levels and the survival rates of NSCLC patients, the relationship between SPHK1 or S1PR3 and EGFR, and the impact of SPHK1 expression on the half-maximal inhibitory concentration (IC50) of gefitinib in NSCLC. In A549cells, the phosphorylation of EGFR was significantly reduced following SPHK1 knockdown. Utilizing SPHK1/S1P/S1PR3 inhibitors, namely PF543, TY52156, and FTY720, we established that the SPHK1/S1P/S1PR3 axis modulates EGFR activation in NSCLC. Furthermore, these signaling inhibitors enhanced the anti-proliferative efficacy of the EGFR-TKI gefitinib. RNA sequencing analysis revealed substantial alterations in 85 differentially expressed genes in NSCLC cells treated with the combination of FTY720 and gefitinib. These genes were predominantly associated with pathways such as axon guidance, microRNAs in cancer, and the JAK-STAT signaling pathway, among others. Overall, targeting the SPHK1/S1P/S1PR3 signaling pathway represents a promising therapeutic strategy to enhance gefitinib sensitivity in NSCLC.

Phase III KEYNOTE-789 Study of Pemetrexed and Platinum With or Without Pembrolizumab for Tyrosine Kinase Inhibitor‒Resistant, EGFR-Mutant, Metastatic Nonsquamous Non-Small Cell Lung Cancer.

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are standard first-line therapy for EGFR-mutant, metastatic non-small cell lung cancer (NSCLC); however, most patients experience disease progression. We report results from the randomized, double-blind, phase III KEYNOTE-789 study of pemetrexed and platinum-based chemotherapy with or without pembrolizumab for TKI-resistant, EGFR-mutant, metastatic nonsquamous NSCLC (ClinicalTrials.gov identifier: NCT03515837). Adults with pathologically confirmed stage IV nonsquamous NSCLC, documented DEL19 or L858R EGFR mutation, and progression after EGFR-TKI treatment were randomly assigned 1:1 to 35 cycles of pembrolizumab 200 mg or placebo once every 3 weeks plus four cycles of pemetrexed and carboplatin or cisplatin once every 3 weeks and then maintenance pemetrexed. Dual primary end points were progression-free survival (PFS) and overall survival (OS). Final PFS testing was completed at the second interim analysis (IA2; data cutoff, December 3, 2021); OS was tested at final analysis (FA; data cutoff, January 17, 2023). Efficacy boundaries were one-sided P = .0117 for PFS and OS. Four hundred ninety-two patients were randomly assigned to pembrolizumab plus chemotherapy (n = 245) or placebo plus chemotherapy (n = 247). At IA2, the median PFS was 5.6 months for pembrolizumab plus chemotherapy versus 5.5 months for placebo plus chemotherapy (hazard ratio [HR], 0.80 [95% CI, 0.65 to 0.97]; P = .0122). At FA, the median OS was 15.9 versus 14.7 months, respectively (HR, 0.84 [95% CI, 0.69 to 1.02]; P = .0362). Grade ≥3 treatment-related adverse events occurred in 43.7% of pembrolizumab plus chemotherapy recipients versus 38.6% of placebo plus chemotherapy recipients. Addition of pembrolizumab to chemotherapy in patients with TKI-resistant, EGFR-mutant, metastatic nonsquamous NSCLC did not significantly prolong PFS or OS versus placebo plus chemotherapy in KEYNOTE-789.

Efficacy of Immune Checkpoint Inhibitors in Postoperative Recurrence of Wild-type EGFR Non-Small Cell Lung Cancer.

Immune checkpoint inhibitors (ICIs) have been widely used in the treatment of non-small cell lung cancer (NSCLC), but specific outcomes of ICIs treatment among patients with postoperative recurrence of NSCLC remain unclear. The objective of the study was to compare the efficacy of ICIs and chemotherapy with conventional chemotherapy only in patients with postoperative recurrence of epidermal growth factor receptor (EGFR) wild-type NSCLC. A retrospective analysis was performed on patients who underwent anatomical lung resection at the Nagoya University Hospital and were treated for postoperative recurrence of wild-type EGFR NSCLC. This study evaluated the prognosis for postoperative recurrence, including ICIs treatment and other clinicopathological factors. Of the 83 patients included in the analysis, 20 patients underwent chemotherapy and 63 patients underwent chemotherapy combined with ICIs. The combination of ICIs and chemotherapy significantly prolonged survival after recurrence (median survival: 33.1 months vs. 22.0 months, p=0.01). In the ICIs group, no significant differences in survival were detected between patients with different programmed death ligand 1 (PD-L1) status (Tumor Proportion Scores: <1%, 1%-49%, ≥50%, p=0.27). Multivariate analysis revealed that postoperative distant recurrence was a significant poor prognostic factor for survival after recurrence (HR=1.85, 95% CI=1.06-3.25, p=0.03), and combining ICIs with chemotherapy significantly improved survival after recurrence (HR=0.43, 95% CI=0.24-0.78, p<0.01). Combination of ICIs with chemotherapy significantly prolonged survival of postoperative recurrence with wild-type EGFR NSCLC regardless of PD-L1 status.

Infusion-Related Reaction Management With Amivantamab for EGFR Exon 20 Insertion Mutation NSCLC: A Practical Guide for Advanced Practitioners

Many targeted therapies to treat genetic mutations in non–small cell lung cancer (NSCLC) have been developed. Amivantamab (Rybrevant), a bispecific antibody targeting the epidermal growth factor receptor (EGFR) and mesenchymal-epithelial transition factor, was approved by the US Food and Drug Administration in 2021 for the treatment of adult patients with locally advanced or metastatic NSCLC EGFR exon 20 insertions, whose disease progressed on or after platinum-based chemotherapy. Amivantamab is administered intravenously weekly for 4 weeks, then every 2 weeks starting at Week 5, as 1,050 mg (body weight [BW] &lt; 80 kg) or 1,400 mg (BW ≥ 80 kg), with the first dose split over 2 days. Infusion-related reactions (IRRs) are common with amivantamab and may present as chills, dyspnea, nausea, chest discomfort, and vomiting. To aid in the prevention, diagnosis, and treatment of IRRs, we evaluated infusion duration, IRR timing, and IRR severity in this post hoc analysis of patients who received amivantamab in CHRYSALIS. Infusion duration decreased over time, with a median infusion time at Cycle 1 Day 1 (C1D1) of 4.70 hours (1,050 mg) and 5.08 hours (1,400 mg), decreasing to 2.20 and 2.25 hours, respectively, by C1D22. Of the 273 IRRs, 98% occurred on C1D1 or C1D2, with median onset and time to resolution of 60 minutes. Most IRRs occurred during the infusion, were low grade, and were manageable with intervention strategies or treatment modifications. Advanced practitioners are critical in preventing, diagnosing, and managing IRRs, including educating patients and families, accurately administering infusions, prescribing premedications, and closely monitoring for IRRs.

EGFR degraders in non-small-cell lung cancer: Breakthrough and unresolved issue.

The epidermal growth factor receptor (EGFR) has been well validated as a therapeutic target for anticancer drug discovery. Osimertinib has become the first globally accessible third-generation EGFR inhibitor, representing one of the most advanced developments in non-small-cell lung cancer (NSCLC) therapy. However, a tertiary Cys797 to Ser797 (C797S) point mutation has hampered osimertinib treatment in patients with advanced EGFR-mutated NSCLC. Several classes of fourth-generation EGFR inhibitors were consequently discovered with the aim of overcoming the EGFRC797S mutation-mediated resistance. However, no clinical efficacy data of the fourth-generation EGFR inhibitors were reported to date, and EGFRC797S mutation-mediated resistance remains an "unmet clinical need." Proteolysis-targeting chimeric molecules (PROTACs) obtained from EGFR-TKIs have been developed to target drug resistance EGFR in NSCLC. Some PROTACs are from nature products. These degraders compared with EGFR inhibitors showed better efficiency in their cellular potency, inhibition, and toxicity profiles. In this review, we first introduce the structural properties of EGFR, the resistance, and mutations of EGFR, and then mainly focus on the recent advances of EGFR-targeting degraders along with its advantages and outstanding challenges.

Abstract 3290: FTO mediates tumor growth and resistance to erlotinib in NSCLC

Abstract Lung cancer, among the most common cancer types, ranks first in cancer associated deaths. Nearly 85% of the lung cancer cases are non-small cell lung cancer (NSCLC). Epidermal growth factor receptor (EGFR), an established marker for NSCLC, is frequently overexpressed on the cell surface. Amplifying mutations often render these receptors activated in a ligand independent manner, therefore, therapies such as erlotinib, an EGFR tyrosine kinase inhibitor (EGFR-TKI), target these activating mutations and inhibit tumor growth. Nevertheless, patients acquire resistance to EGFR TKI within 9-14 months of treatment. Recent studies show that fat mass and obesity- associated (FTO) gene, initially identified to increase the body mass index, plays a major role in cancer development and acquired therapy resistance in several cancer types. FTO demethylates m6A mRNA and modulates tumorigenesis, and drug resistance. In this study, we explored the functions of FTO in EGFR TKI resistance in NSCLC. To study the expression of FTO in erlotinib resistant cells, we used wildtype-EGFR NSCLC cell lines (H2170, H358) and mutant EGFR NSCLC cell lines (H1975, PC9) that were rendered resistant to erlotinib. Our RT-qPCR results demonstrated that FTO was upregulated by 1.7-3.0 fold in erlotinib resistant H2170, H358, PC9 and H1975 cells. FTO protein was upregulated by 1.3-1.6 fold as seen by western blotting, and by 1.7 to 2.6 fold in the nucleus of erlotinib resistant H1975, H2170 and PC9 cell lines by immunofluorescence. Furthermore, we investigated FTO inhibition with Dac51 (FTOi) on cell viability and cell migration properties. MTT cell viability assay showed a 9-17% decrease in cell viability when treated with a combination of Dac51 and erlotinib compared to Dac51 alone in erlotinib resistant H2170 and PC9 cells, respectively. The combinatory treatment showed an additive effect compared to the Dac51 and erlotinib treatments alone. Wound healing assay revealed an 18% open wound area after 48-hour treatment with both Dac51 and erlotinib compared to 0.1% after treatment with erlotinib alone in erlotinib resistant H2170 cells. To evaluate the effect of siRNA mediated FTO (siFTO) knockdown on cell viability and energy metabolism, MTT and luciferase assays were performed. MTT assay showed a 21-28% decrease in viability in erlotinib resistant H1975, H2170, PC9 cells, demonstrating increase in the erlotinib efficacy, as compared to the mock siRNA treatment. Luciferase assay showed an inverse relationship between the FTO and ATP, where the latter was upregulated by 1.3 to 3.4 folds in erlotinib resistant H1975, H2170 and PC9 cells, when treated with siFTO, suggesting its involvement in the energy requirements of the NSCLC cells. In conclusion, our study suggests FTO was upregulated in erlotinib resistant NSCLC cells on both the gene and protein levels. FTO could mediate resistance to EGFR TKI possibly through cell proliferation and migration and help with prognosis of NSCLC patients. Citation Format: Aayush Rastogi, Rong Qiu, Neelu Puri. FTO mediates tumor growth and resistance to erlotinib in NSCLC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3290.

Leucine Zipper Downregulated in Cancer-1 Interacts with Clathrin Adaptors to Control Epidermal Growth Factor Receptor (EGFR) Internalization and Gefitinib Response in EGFR-Mutated Non-Small Cell Lung Cancer.

The epidermal growth factor receptor (EGFR) is a common driver of non-small cell lung cancer (NSCLC). Clathrin-mediated internalization (CMI) sustains EGFR signaling. AXL is associated with resistance to EGFR-tyrosine kinase inhibitors (TKIs) in EGFR-mutated (EGFRM) NSCLC. We investigated the effects of Leucine zipper downregulated in cancer-1 (LDOC1) on EGFR CMI and NSCLC treatment. Coimmunoprecipitation, double immunofluorescence staining, confocal microscopy analysis, cell surface labelling assays, and immunohistochemistry studies were conducted. We revealed that LDOC1 interacts with clathrin adaptors through binding motifs. LDOC1 depletion promotes internalization and plasma membrane recycling of EGFR in EGFRM NSCLC PC9 and HCC827 cells. Membranous and cytoplasmic EGFR decreased and increased, respectively, in LDOC1 (-) NSCLC tumors. LDOC1 depletion enhanced and sustained activation of EGFR, AXL, and HER2 and enhanced activation of HER3 in PC9 and HCC827 cells. Sensitivity to first-generation EGFR-TKIs (gefitinib and erlotinib) was significantly reduced in LDOC1-depleted PC9 and HCC827 cells. Moreover, LDOC1 downregulation was significantly associated (p < 0.001) with poor overall survival in patients with EGFRM NSCLC receiving gefitinib (n = 100). In conclusion, LDOC1 may regulate the efficacy of first-generation EGFR-TKIs by participating in the CMI of EGFR. Accordingly, LDOC1 may function as a prognostic biomarker for EGFRM NSCLC.

Amivantamab compared with real-world therapies in patients with advanced non-small cell lung cancer EGFR Exon 20 insertion mutations after platinum-based chemotherapy

Background In the single-arm CHRYSALIS trial, advanced non-small cell lung cancer patients harboring epidermal growth factor receptor (EGFR) exon 20 insertion (Exon 20ins) showed durable responses to amivantamab, an EGFR-MET bispecific antibody targeting tumors with EGFR Exon 20ins. This study compared the effectiveness of amivantamab to real-world systemic anti-cancer therapies in Japan. Patients and methods External control patients were selected by applying CHRYSALIS eligibility to Japanese patients from LC-SCRUM-Asia. External control patients were included for every qualifying line of therapy after platinum-based chemotherapy. Propensity score weighting was applied to external control patients to adjust for differences in baseline characteristics. Outcomes were compared between external control patients, and all and Asian-only CHRYSALIS patients using weighted Cox proportional hazards regression models for progression-free survival (PFS), time to next therapy (TTNT), and overall survival (OS), and generalized estimating equations with repeated measurements for overall response rate (ORR). Results One hundred fifteen CHRYSALIS and 94 external control patients were identified. Compared to external control patients, amivantamab-treated patients had significantly longer OS (median OS 19.88 vs 14.09 months, HR [95% CI] 0.59 [0.40–0.88]), PFS (median PFS 6.74 vs 4.73 months, HR 0.59 [0.45–0.78]), TTNT (median TTNT 12.16 vs 5.09 months, HR 0.39 [0.29–0.53]), and significantly higher ORR (41.7% vs 14.1%). Analyses of amivantamab-treated Asian patients (n = 61) showed similar clinical benefits. Conclusion In the absence of clinical evidence from randomized clinical trials, this study reflects the benefit of amivantamab after platinum-based chemotherapy for advanced non-small cell lung cancer patients harboring EGFR Exon 20ins, compared to current real-world therapies.

JMJD5 inhibits lung cancer progression by facilitating EGFR proteasomal degradation

Aberrant activation of epidermal growth factor receptor (EGFR) signaling is closely related to the development of non-small cell lung cancer (NSCLC). However, targeted EGFR therapeutics such as tyrosine kinase inhibitors (TKIs) face the challenge of EGFR mutation-mediated resistance. Here, we showed that the reduced JmjC domain-containing 5 (JMJD5) expression is negatively associated with EGFR stability and NSCLC progression. Mechanically, JMJD5 cooperated with E3 ligase HUWE1 to destabilize EGFR and EGFR TKI-resistant mutants for proteasomal degradation, thereby inhibiting NSCLC growth and promoting TKI sensitivity. Furthermore, we identified that JMJD5 can be transported into recipient cells via extracellular vesicles, thereby inhibiting the growth of NSCLC. Together, our findings demonstrate the tumor-suppressive role of JMJD5 in NSCLC and suggest a putative therapeutic strategy for EGFR-related NSCLC by targeting JMJD5 to destabilize EGFR.

Osimertinib rechallenge in advanced EGFR non-small cell lung cancer patients.

e21196 Background: Treatment after front line osimertinib (osi) for epidermal growth factor receptor (EGFR) mutated advanced non-small cell lung cancer (NSCLC) remains a clinical challenge. Interval chemotherapy after osi may eradicate clones responsible for EGFR tyrosine kinase (TKI) resistance, which may re-sensitize the tumor to EGFR inhibition. We describe outcomes of metastatic EGFR NSCLC patients who undergo osi rechallenge. Methods: NSCLC patients with confirmed EGFR mutation were retrospectively reviewed from a single institutional database from 1/2010-12/2022. We identified patients who received osi after interval therapy following initial osi progression. Patient characteristics and tumor type were collected via chart review. Response was determined using RECIST 1.1. Results: Seventeen patients with osi rechallenge after initial progression were identified. Median age at time of osi rechallenge was 62 yrs (range 42-73). Patients were predominantly female (n = 11, 65%), white (n = 9, 53%) and Asian (n = 8, 47%), never smokers (n = 13, 77%). Patients had either del19 mutation (n = 10, 59%) or L858R mutation (n = 7, 41%). Twelve patients (71%) received a 1st or 2nd generation EGFR TKI (erlotinib n = 10, afatinib n = 2) prior to initial osi; eight patients (47%) had confirmed T790M mutation. Eight patients (47%) had CNS metastases prior to osi rechallenge. Twelve patients (71%) had ECOG 0-1 at time of rechallenge. Patients had a median of 4 (range 2-5) lines of therapy prior to osi rechallenge. Median time between initial osi discontinuation and osi rechallenge was 13.8 months (range 3.2-50.7). In the interim, 17 patients (100%) received chemotherapy, 2 (12%) received immunotherapy monotherapy, 3 (18%) received antibody drug conjugate, and 1 (6%) received TKI. Sixteen patients had follow-up restaging CT scans; 1 died before restaging imaging was obtained. Two patients achieved partial response (PR) (13%), and 6 patients had stable disease (SD) as the best response (38%). Median duration of initial osi was 13.9 months (range 1.9-26.4), and median duration of osi rechallenge was 3.6 months (range 1.0-10.3). Patients who had PR/SD were on osi for 7.5 months (range 2.7-10.3). Ten (59%) patients received osi rechallenge for at least 3 months duration, and 6 (35%) received osi rechallenge for at least 6 months duration. Conclusions: Osi rechallenge is a potential option for advanced EGFR NSCLC patients to obtain disease control at later lines of therapy. Further research is needed to characterize mechanisms of targeted therapy resistance and better select patients who can benefit from EGFR TKI re-exposure.

A-to-I edited miR-411-5p targets MET and promotes TKI response in NSCLC-resistant cells.

Non-small cell lung cancer (NSCLC) patients carrying an epidermal growth factor receptor (EGFR) mutation have an initial favorable clinical response to the tyrosine kinase inhibitors (TKIs). Unfortunately, rapid resistance occurs mainly because of genetic alterations, including amplification of the hepatocyte growth factor receptor (MET) and its abnormal activity. The RNA post-transcriptional modifications that contribute to aberrant expression of MET in cancer are largely under-investigated and among them is the adenosine-to-inosine (A-to-I) RNA editing of microRNAs. A reduction of A-to-I editing in position 5 of miR-411-5p has been identified in several cancers, including NSCLC. In this study, thanks to cancer-associated gene expression analysis, we assessed the effect of the edited miR-411-5p on NSCLC cell lines. We found that edited miR-411-5p directly targets MET and negatively affects the mitogen-activated protein kinases (MAPKs) pathway. Considering the predominant role of the MAPKs pathway on TKIs resistance, we generated NSCLC EGFR mutated cell lines resistant to TK inhibitors and evaluated the effect of edited miR-411-5p overexpression. We found that the edited miR-411-5p reduces proliferation and induces apoptosis, promoting EGFR TKIs response in NSCLC-resistant cells.

Deep learning for predicting epidermal growth factor receptor mutations of non-small cell lung cancer on PET/CT images.

Predicting the mutation status of the epidermal growth factor receptor (EGFR) gene based on an integrated positron emission tomography/computed tomography (PET/CT) image of non-small cell lung cancer (NSCLC) is a noninvasive, low-cost method which is valuable for targeted therapy. Although deep learning has been very successful in robotic vision, it is still challenging to predict gene mutations in PET/CT-derived studies because of the small amount of medical data and the different parameters of PET/CT devices. We used the advanced EfficientNet-V2 model to predict the EGFR mutation based on fused PET/CT images. First, we extracted 3-dimensional (3D) pulmonary nodules from PET and CT as regions of interest (ROIs). We then fused each single PET and CT image. The network model was used to predict the mutation status of lung nodules by the new data after fusion, and the model was weighted adaptively. The EfficientNet-V2 model used multiple channels to represent nodules comprehensively. We trained the EfficientNet-V2 model through our PET/CT fusion algorithm using a dataset of 150 patients. The prediction accuracy of EGFR and non-EGFR mutations was 86.25% in the training dataset, and the accuracy rate was 81.92% in the validation set. Combined with experiments, the demonstrated PET/CT fusion algorithm outperformed radiomics methods in predicting EGFR and non-EGFR mutations in NSCLC.

EP08.02-141 ‘Our’ EGFR population - experience in a secondary center

Epidermal growth factor receptor (EGFR) mutations are the most common among non-small cell lung cancer (NSCLC), with available target treatment with tyrosine-kinase inhibitor (TKI) as first-line on advanced disease. The aim of this study was to evaluate the demographic characteristics of patients with advanced NSCLC EGFR mutated, treatments performed and outcomes.

The Therapy of Osimertinib for EGFR Mutation—Non-small Cell Lung Cancer

Lung cancer is still a disease cause of human beings mortality. Lung cancer is divided into numerous kinds, with non-small cell lung cancer (NSCLC) accounting for up to 85% of cases. KRAS,ALK,HER2, and PD-1 are currently identified targets for NSCLC therapy. And the therapy of lung cancer, molecular-targeted medicines have recently demonstrated encouraging outcomes and NSCLC was treated with a variety of molecular targeted drugs. In NSCLC, EGFR mutations are also quite prevalent. The human epidermal growth factor receptor (EGFR) belongs to the HER receptor family. When epidermal growth factor (EGF), transforming growth factor (TGF) and other ligands combine with EGFR, the downstream signaling pathway is activated, thereby regulating cell growth, proliferation, migration, anti-apoptosis. EGFR-TKI-targeted medicines are currently the most common treatment for NSCLC with an EGFR mutation. EGFR-TKI medicines of the first and second generations, such as erlotinib, gefitinib, and afatinib are used to treat EGFR NSCLC as first-line drugs. However, due to the emergence of medication resistance, a novel EGFR mutation -T790M has emerged. As a result, the EGFR-TKI medication has been upgraded to the third generation. The most representative of the three generations of medicines is osimertinib. It inhibits EGFR growth by targeting both EGFR and T790M mutant sites. Osimertinib also lessens some drug toxicity when compared to earlier first- and second-generation medicines. In this review paper, we will provide background information about EGFR NSCLC and the three generations of medications used to treat it.

Advances in Treatment of Non-small Cell Lung Cancer Harboring EGFR Exon 20 Insertion Mutations

表皮生长因子受体（epidermal growth factor receptor, EGFR）外显子20插入突变是EGFR突变的第三大常见类别，约占所有EGFR突变阳性非小细胞肺癌（non-small cell lung cancer, NSCLC）的5%-12%。携带EGFR外显子20插入突变的NSCLC患者临床特征与“经典”EGFR激活突变人群相似，但预后很差。EGFR外显子20插入突变异质性高，可导致EGFR不同构象变化。大多数（几乎90%的病例）发生在α-C-螺旋后的Loop环结构区，最常报告的插入突变亚型为D770_N771 > ASVDN（A767_V769dupASV），突变频率为21%-28%。目前已知EGFR外显子20插入突变的NSCLC对既往已批准的EGFR酪氨酸激酶抑制剂原发性耐药，而且对传统化疗和免疫治疗也不敏感。近期Amivantamab与Mobocertinib在美国的获批改变了EGFR外显子20插入突变的NSCLC患者的治疗模式。此外，针对NSCLC EGFR外显子20插入突变的其他新型靶向药物正在研发中，期待为该类患者带来更多生存获益。本文就近年来伴有EGFR外显子20插入突变的NSCLC的临床研究进展进行归纳总结，旨在为该类患者的临床治疗提供参考。

Dysregulated circulating miR-4429 serves as a novel non-invasive biomarker and is correlated with EGFR mutation in patients with non-small cell lung cancer.

This study aimed to investigate the correlation between microRNA (miR)-4429 and epidermal growth factor receptor (EGFR), the expression, and clinical significance of miR-4429 in patients with non-small cell lung cancer (NSCLC), and the relationship between miR-4429 and EGFR mutation in NSCLC patients. Blood samples were collected from 122 NSCLC patients and 72 healthy volunteers. miR-4429 expression and EGFR mRNA expression were detected by real-time quantitative polymerase chain reaction. Correlation between miR-4429 and EGFR was evaluated by dual-luciferase reporter assay and the Pearson correlation analysis. The ability of serum miR4429 to discriminate between NSCLC patients and healthy controls, and to discriminate between EGFR wild-type (EGFR-W) and EGFR mutant-type (EGFR-M) patients was assessed using receiver operating characteristic analysis. The relationship between miR-4429 and NSCLC patients’ survival was identified by KaplanMeier survival curves and log-rank test. The prognostic value of miR-4429 in NSCLC patients was evaluated by Cox regression analysis. miR-4429 could directly bind to EGFR. Serum miR-4429, decreased in NSCLC patients, was negatively correlated with serum EGFR mRNA expression in NSCLC patients. In addition, miR-4429 had a high diagnostic value for screening NSCLC patients from healthy controls, and was independently correlated with survival prognosis of NSCLC patients. Moreover, miR4429 was decreased in EGFR-M patients, which had a certain screening ability for EGFRM patients. Our findings indicate that miR-4429 is negatively correlated with EGFR in NSCLC, and may function as a diagnostic and prognostic biomarker for NSCLC patients. Additionally, miR-4429 is associated with EGFR mutation in NSCLC patients.

Role of Immune Checkpoint Inhibitor Therapy in Advanced EGFR-Mutant Non-Small Cell Lung Cancer.

Over the last decade, the treatment of advanced non-small cell lung cancer (NSCLC) has undergone rapid changes with innovations in oncogene-directed therapy and immune checkpoint inhibitors. In patients with epidermal growth factor receptor (EGFR) gene mutant (EGFRm) NSCLC, newer-generation tyrosine kinase inhibitors (TKIs) are providing unparalleled survival benefit and tolerability. Unfortunately, most patients will experience disease progression and thus an urgent need exists for improved subsequent lines of therapies. The concurrent revolution in immune checkpoint inhibitor (ICI) therapy is providing novel treatment options with improved clinical outcomes in wild-type EGFR (EGFRwt) NSCLC; however, the application of ICI therapy to advanced EGFRm NSCLC patients is controversial. Early studies demonstrated the inferiority of ICI monotherapy to EGFR TKI therapy in the first line setting and inferiority to chemotherapy in the second line setting. Additionally, combination ICI and EGFR TKI therapies have demonstrated increased toxicities, and EGFR TKI therapy given after first-line ICI therapy has been correlated with severe adverse events. Nonetheless, combination therapies including dual-ICI blockade and ICI, chemotherapy, and angiogenesis inhibitor combinations are areas of active study with some intriguing signals in preliminary studies. Here, we review previous and ongoing clinical studies of ICI therapy in advanced EGFRm NSCLC. We discuss advances in understanding the differences in the tumor biology and tumor microenvironment (TME) of EGFRm NSCLC tumors that may lead to novel approaches to enhance ICI efficacy. It is our goal to equip the reader with a knowledge of current therapies, past and current clinical trials, and active avenues of research that provide the promise of novel approaches and improved outcomes for patients with advanced EGFRm NSCLC.

Real-world evaluation of molecular testing and treatment patterns for EGFR mutations in non-small cell lung cancer in Latin America.

Lung cancer is a leading cause of cancer-related deaths in Latin America, with non-small cell lung cancer (NSCLC) being the most prevalent. The current study aimed to report real-world data on epidermal growth factor receptor (EGFR) mutational testing and treatment regimens at diagnosis and progression in patients with metastatic NSCLC across four Latin American countries (Argentina, Chile, Colombia and Uruguay). A retrospective, multicenter, observational study was conducted in patients with NSCLC using medical records from participating countries. The study population was categorized into two cohorts: Cohort 1 comprised of newly diagnosed, treatment-naïve patients with stage IV NSCLC; and cohort 2 comprised of stage IV NSCLC EGFR mutation (EGFRm)-positive patients who had progressed after first- or second-generation EGFR-tyrosine kinase inhibitor (TKI) treatment. Measures included demographic variables, health characteristics, treatment regimen, molecular testing rate and turnaround time at diagnosis and at progression for cohorts 1 and 2, respectively. Descriptive statistics were used to summarize all study measures. Of the 462 patients enrolled, 431 were newly diagnosed or treatment naïve with metastatic NSCLC. In cohort 1, the majority of patients with private health insurance (57.31%) underwent molecular diagnosis while only 41.3% of patients within the public sector had access to testing. The average molecular testing rate in cohort 1 varied across countries, with Argentina having the highest testing rate (79%) and Uruguay the lowest (27.63%). EGFRm was observed in 22% of patients. Cohort 2 comprised 31 patients who had progressed after first- or second-generation EGFR-TKI treatment and of these, only 22 (70.97%) underwent testing after progression. Access to molecular testing is still a challenge impacting the choice of first-line treatment in Latin American patients with NSCLC. These findings underline the unmet needs of ensuring early diagnosis, molecular profiling and use of correct treatment to alleviate NSCLC burden in the region.

Chemical Genetics Screen Identifies COPB2 Tool Compounds That Alters ER Stress Response and Induces RTK Dysregulation in Lung Cancer Cells

Activating mutations in the epidermal growth factor receptor (EGFR) are common driver mutations in non-small cell lung cancer (NSCLC). First, second and third generation EGFR tyrosine kinase inhibitors (TKIs) are effective at inhibiting mutant EGFR NSCLC, however, acquired resistance is a major issue, leading to disease relapse. Here, we characterize a small molecule, EMI66, an analog of a small molecule which we previously identified to inhibit mutant EGFR signalling via a novel mechanism of action. We show that EMI66 attenuates receptor tyrosine kinase (RTK) expression and signalling and alters the electrophoretic mobility of Coatomer Protein Complex Beta 2 (COPB2) protein in mutant EGFR NSCLC cells. Moreover, we demonstrate that EMI66 can alter the subcellular localization of EGFR and COPB2 within the early secretory pathway. Furthermore, we find that COPB2 knockdown reduces the growth of mutant EGFR lung cancer cells, alters the post-translational processing of RTKs, and alters the endoplasmic reticulum (ER) stress response pathway. Lastly, we show that EMI66 treatment also alters the ER stress response pathway and inhibits the growth of mutant EGFR lung cancer cells and organoids. Our results demonstrate that targeting of COPB2 with EMI66 presents a viable approach to attenuate mutant EGFR signalling and growth in NSCLC.

The pre-clinical discovery and development of osimertinib used to treat non-small cell lung cancer

ABSTRACT Introduction: Osimertinib is currently the only FDA- and EMA-approved third-generation small-molecule epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI). It was initially indicated for second-line treatment of patients with metastatic EGFR T790M mutation-positive non-small cell lung cancer (NSCLC) and got approved for first-line treatment of EGFR activation mutation-positive metastatic NSCLC in 2018. Most recently, the FDA granted approval for the adjuvant treatment of patients with early-stage mutated EGFR NSCLC after tumor resection. Areas covered: This drug discovery case history focuses on the key studies that led to the preclinical discovery and development of osimertinib. The authors focus on published preclinical studies by scientists from AstraZeneca and highlight key events in the clinical development. Expert opinion: Although eventually compromised by the cellular plasticity of the tumor and the inevitable acquisition of drug resistance through the use of osimertinib, its key role in the treatment of NSCLC with specific EGFR mutations will be maintained in the near future. As the genome of EGFR is highly labile and since the rapid development of new mutants remains an issue, there is still room for improvement for the next generation of inhibitors.