Epidermal Growth Factor Receptor Tyrosine Kinase Inhibitors Research Articles

Advanced lung adenocarcinoma with EGFR 19-del mutation transforms into squamous cell carcinoma after EGFR tyrosine kinase inhibitor treatment

In this editorial we comment on the article by Ji et al . We focus specifically on the EGFR tyrosine kinase inhibitor (EGFR-TKI) treatment and the development of drug resistance to EGFR-TKIs.

Pyrrolo[2,3-D]Pyrimidines as EGFR and VEGFR Kinase Inhibitors: A Comprehensive SAR Review.

Tyrosine kinases are implicated in a wide array of cellular physiological processes, including cell signaling. The discovery of the BCR-ABL tyrosine kinase inhibitor imatinib and its FDA approval in 2001 paved the way for the development of small molecule chemical entities of diverse structural backgrounds as tyrosine kinase inhibitors for the treatment of various ailments. Two of the most prominent tyrosine kinases as drug targets are the epidermal growth factor receptor (EGFR) and the vascular endothelial growth factor receptor (VEGFR), as evidenced by the clinical success of their many inhibitors in the drug market. Among several other physiological roles, EGFR regulates epithelial tissue development and homeostasis, while VEGFR regulates tumor-induced angiogenesis. The pyrrolo[2,3-d]pyrimidine nucleus represents a deaza-isostere of adenine, the nitrogenous base of ATP. The recent introduction of many pyrrolo[2,3-d]pyrimidines to the drug market as tyrosine kinase inhibitors makes them a hot topic in the medicinal chemistry research area at the present time. This review article comprehensively sheds light on the structure-activity relationship (SAR) of pyrrolo[2,3-d]pyrimidines as EGFR and VEGFR tyrosine kinase inhibitors, aiming to provide help medicinal chemists in the design of future pyrrolopyrimidine kinase inhibitors.

Exosomes derived from IFNγ-stimulated mesenchymal stem cells protect photoreceptors in RCS rats by restoring immune homeostasis through tsRNAs.

Retinitis pigmentosa is a neurodegenerative disease with major pathologies of photoreceptor apoptosis and immune imbalance. Mesenchymal stem cells (MSCs) have been approved for clinical application for treating various immune-related or neurodegenerative diseases. The objective of this research was to investigate the mechanisms underlying the safeguarding effects of MSC-derived exosomes in a retinal degenerative disease model. Interferon gamma-stimulated exosomes (IFNγ-Exos) secreted from MSCs were isolated, purified, and injected into the vitreous body of RCS rats on postnatal day (P) 21. Morphological and functional changes in the retina were examined at P28, P35, P42, and P49 in Royal College of Surgeons (RCS) rats. The mechanism was explored using high-throughput sequencing technology and confirmed in vitro. Treatment with IFNγ-Exo produced better protective effects on photoreceptors and improved visual function in RCS rats. IFNγ-Exo significantly suppressed the activated microglia and inhibited the inflammatory responses in the retina of RCS rats, which was also confirmed in the lipopolysaccharide-activated microglia cell line BV2. Furthermore, through tRNA-derived small RNA (tsRNA) sequencing, we found that IFNγ-Exos from MSCs contained higher levels of Other-1_17-tRNA-Phe-GAA-1-M3, Other-6_23-tRNA-Lys-TTT-3, and TRF-57:75-GLN-CGG-2-m2 than native exosomes, which mainly regulated inflammatory and immune-related pathways, including the mTOR signaling pathway and EGFR tyrosine kinase inhibitor resistance. IFNγ stimulation enhanced the neuroprotective effects of MSC-derived exosomes on photoreceptors of the degenerative retina, which may be mediated by immune regulatory tsRNAs acting on microglia. In conclusion, IFNγ-Exo is a promising nanotherapeutic agent for the treatment of retinitis pigmentosa.

EXTH-72. INTEGRATED MULTIOMIC ANALYSIS OF ISOGENIC EGFRVIII MODELS OF GBM REVEALS EXPLOITABLE THERAPEUTIC VULNERABILITIES

Abstract Glioblastoma (GBM) is the most common primary malignant brain tumor with an abysmal 15-month median survival. Therefore, novel therapeutic interventions are urgently needed. EGFR is a receptor tyrosine kinase that is mutated in over 50% of GBM and is a logical target for precision oncology approaches. While aberrant EGFR signaling has been successfully targeted in other cancers, early attempts to target EGFR in GBM clinical trials have not been successful. Since these early trials, several studies have revealed that GBM EGFR biology is unique and cannot be generalized from other EGFR-driven neoplasms. To better understand EGFR biology in a GBM-specific context, we have characterized the GBM transcriptome with RNAseq, the epigenome with CUT&RUN, and the kinase proteome with Multiplexed inhibitor beads with Mass Spectrometry (MIB-MS), collectively referred to as ‘multiomics’, after modeling EGFR resistance. An isogenic mouse astrocyte (mAc) model of GBM was genetically engineered to overexpress EGFRvIII (CEv3), the most common EGFR mutation in GBM. Expression of EGFRvIII induces a unique multiomic profile that mediates many hallmark cancer phenotypes including proliferation and stemness. Chronic EGFR resistance was modeled both in vitro and in vivo through continuous exposure to erlotinib or gefitinib, EGFR tyrosine kinase inhibitors (TKI). Additionally, acute EGFR resistance was modeled using a single exposure to EGFR TKI afatinib or neratinib in vitro over a 48-hour time course. Preliminary multiomic characterization of these data has revealed several targets that can be further investigated for therapeutic exploitation. Further investigation into these targets using orthotopic allografts with CEv3 cells shows that combinatorial therapy with neratinib and abemacilib, a CDK inhibitor, significantly (p < 0.001, n= 20 mice per group) extends survival (56 days) compared to neratinib alone (31.5 days). Future integrated multiomic analysis aims to elucidate the synergistic relationship between neratinib and abemacilib.

RBM15 facilitates osimertinib resistance of lung adenocarcinoma through m6A-dependent epigenetic silencing of SPOCK1.

Lung cancer is the leading cause of cancer-related mortality globally. N6-methyladenosine (m6A) is the most abundant modification in mammalian mRNA and is involved in the biological regulation of tumors, including lung cancer. However, the role of m6A-related proteins, such as RNA-binding motif protein 15 (RBM15), in lung cancer progression remains largely unknown. Our study indicated that RBM15 is significantly overexpressed in lung adenocarcinoma, serving as an independent prognostic factor for poor outcomes and facilitating tumor cell proliferation and migration. RBM15 was markedly elevated in patients with EGFR mutations, correlating with a poorer prognosis, while it had negligible prognostic value in EGFR wild-type patients. As EGFR-tyrosine kinase inhibitors (TKIs) are the standard treatment for patients with EGFR mutations, we subsequently determined that RBM15 drives osimertinib resistance via a novel mechanism: enhancing m6A modification of cwcv- and kazal-like domains proteoglycan 1 (SPOCK1) mRNA, promoting epithelial-mesenchymal transition-mediated osimertinib resistance through a bypass activation pathway. These findings were validated in osimertinib-resistant H1975 cells and organoids from patients with osimertinib-resistant lung adenocarcinoma. Furthermore, the RBM15-SPOCK1 axis was activated in drug-tolerant persister cells, indicating that early targeting of RBM15 during EGFR-TKI treatment could dramatically extend the patient response and benefit from TKI therapy. Our results emphasize the critical role of RBM15 in reversing EGFR-TKI resistance and propose it as a promising therapeutic target for prolonging TKI treatment benefits in patients with lung adenocarcinoma.

DDDR-43. ERAS-801 IS A SELECTIVE BRAIN-PENETRANT EGFR INHIBITOR WITH IMPROVED ACTIVITY AGAINST EGFR EXTRACELLULAR DOMAIN-MUTANT GLIOBLASTOMA

Abstract Epidermal growth factor receptor (EGFR) is a driver of nearly 50% of glioblastoma (GBM), yet EGFR inhibitors have failed in GBM (e.g., erlotinib, lapatinib, neratinib, gefitinib, and afatinib) due to poor CNS penetration and/or an inability to inhibit EGFR in its wildtype and extracellular domain (ECD) mutated forms (e.g., EGFRvIII). Here we describe ERAS-801, a reversible and selective EGFR tyrosine kinase inhibitor with unique binding properties that enable potent activity for amplified and ECD mutant EGFR. ERAS-801 demonstrated the highest nonclinical CNS penetration out of all tested EGFR inhibitor comparators. Accordingly, relative to other EGFR inhibitors tested in GBM trials (e.g., erlotinib, lapatinib, and osimertinib), ERAS-801 showed superior survival benefit in EGFR altered orthotopic PDX models. Finally, further characterization of ERAS-801 in a preclinical trial of glioma orthotopic PDX models that capture the molecular heterogeneity of GBM, ERAS-801 demonstrated a significant survival benefit at a 25 mg/kg QD dose in the vast majority of EGFR-driven orthotopic GBM PDX models, with FDG-PET imaging serving as a non-invasive biomarker of response. Based on these nonclinical data, ERAS-801 is currently under clinical investigation for GBM.

Exploring the therapeutic potential of marine actinomycetes: a systems biology-based approach for Alzheimer’s disease treatment

Abstract Background This study addresses the urgent need for novel Alzheimer’s Disease (AD) treatments, focusing on the therapeutic potential of marine Actinomycetes compounds. Current AD therapies provide only symptomatic relief, necessitating a paradigm shift toward more effective interventions. Methodology Ninety-one bioactive compounds were methodically identified from Actinomycetes strains in the Indian Ocean. Rigorous ADME analysis and in silico toxicological screening narrowed the selection to 19 compounds, including Helquinoline, Bonactin, Azamerone, and Arcyriaflavin A. These compounds demonstrated favorable drug-like properties and activity against crucial AD targets. Utilizing network pharmacology, a bioactive-target-disease association network was constructed to unveil intricate relationships between compounds and target proteins in the context of AD. Topological analysis highlighted influential targets such as SRC, MAPK1, EGFR, PRKCA, PRKCD, and CDK2. Protein–Protein Interaction (PPI) mapping revealed interconnected pathways influenced by these compounds. Results Focus narrowed to the top 10 pathways associated with key hub–bottleneck genes. The GnRH signaling, EGFR tyrosine kinase inhibitor resistance, and ErbB signaling pathways exhibited remarkable fold enrichment, emphasizing their central roles in AD pathogenesis. The GnRH signaling pathway aligned with endocrine dysregulation in AD, EGFR’s dual role in prion-like propagation and amyloid-β pathology, and ErbB signaling’s multifaceted contributions. Conclusion In conclusion, this study presents marine Actinomycetes compounds as potential poly-pharmacological modulators in AD. Despite promising results, cautious optimism is warranted, requiring further experimental validation. The identified compounds and pathways offer a novel perspective, laying the groundwork for targeted interventions within the intricate landscape of AD. This research contributes to advancing AD therapeutics within a systems biology framework, introducing innovative approaches to address this complex neurodegenerative disorder.

Network Pharmacology and Molecular Dynamics Simulations Reveal the Mechanism of Total Alkaloid Components in Anisodus Tanguticus (Maxim.) Pascher in Treating Inflammation and Pain.

This study aimed to elucidate the mechanism that total alkaloids in Anisodus tanguticus (AT)(Maxim.) Pascher played anti-inflammatory and analgesic effects. In this paper, the anti-inflammatory effect in the total alkaloids of AT was confirmed via lipopolysaccharide (LPS)-induced inflammation model in RAW 264.7 cells and the main components of AT were immediately analyzed by UPLC/MS. Disease targets were obtained in GeneCards and DisGeNET. Targets of major compounds were searched in ETCM, TCMSP and other databases. The protein-protein interaction (PPI) network was constructed using STRING database, and Cytoscape was used for core targets screening. GO and KEGG enrichment analysis were performed using Daivid database. Sailvina was used for molecular docking. Molecular dynamics simulation analysis was performed using the Amber 20 program. The results showed that the main components in AT were anisodamine, atropine, fabiatrin, scopolamine, scopoletin and scopolin, possibly exerting anti-inflammatory and analgesic effects through pathways such as EGFR tyrosine kinase inhibitor resistance and IL-17 signaling pathway. Fabiatrin and scopolin could be potential drugs with good anti-inflammatory and analgesic effects.

Osimertinib Efficacy and Safety in Treating Epidermal Growth Factor Receptor Mutation-Positive Advanced Non-Small-Cell Lung Cancer: A Meta-Analysis.

This study compared the safety and efficacy of osimertinib, a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), with those of other TKIs and its use alongside bevacizumab in patients with EGFR mutation-positive advanced non-small-cell lung cancer. PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, Wanfang, and VIP databases were used to conduct extensive searches for relevant randomized controlled trials until January 30, 2024. Osimertinib monotherapy favored disease control rate, whereas the comparator treatment arm favored overall survival. Using subgroup analysis, the objective response rate and progression-free survival (PFS) were significantly elevated by Osimertinib monotherapy compared with pemetrexed combined with carboplatin or cisplatin. The comparator treatment arm receiving gefitinib or erlotinib significantly favored progression-free survival and overall survival compared with osimertinib monotherapy. In patients treated with osimertinib monotherapy, the incidence of all adverse events (AEs) decreased compared with comparator treatment arm. Anemia was the only AE associated with osimertinib monotherapy. Pemetrexed combined with carboplatin or cisplatin resulted in greater loss of appetite than osimertinib monotherapy. The most associated AE of osimertinib monotherapy was diarrhea, according to network analysis. Although its efficacy is not consistent with other EGFR TKIs, osimertinib was associated with a decrease in AEs in patients with EGFR mutation-positive advanced non-small-cell lung cancer.

Loss of CDKN2A Enhances the Efficacy of Immunotherapy in EGFR Mutant Non-Small Cell Lung Cancer.

Mutant epidermal growth factor receptor (EGFR) is a common driver of non-small cell lung cancer (NSCLC). While mutant EGFR has been reported to limit the efficacy of immunotherapy, a subset of EGFR mutant NSCLC patients benefit from treatment with immune checkpoint inhibitors. A better understanding of how co-occurring genomic alterations in oncogenic driver genes impact immunotherapy efficacy may provide a more complete understanding of cancer heterogeneity and identify biomarkers of response. Here, we investigated the effects of frequent EGFR co-mutations in EGFR mutant lung cancer models and identified loss-of-function mutation of CDKN2A as a potential sensitizer to anti-PD-1 treatment in vitro and in vivo. Mechanistically, CDKN2A loss impacted the composition of the tumor immune microenvironment (TIME) by promoting the expression of PD-L2 through reduced ubiquitination of c-Myc, and mutant EGFR cooperated to upregulate c-Myc and PD-L2 by activating the MAPK pathway. Blocking PD-L2 induced anti-tumor immune responses mediated by CD8+ T cells in EGFR/CDKN2A co-mutated lung cancer. Importantly, a small-molecule PD-L2 inhibitor, zinc undecylenate, remodeled the TIME of EGFR/CDKN2A co-mutant tumors and enhanced the anti-tumor efficacy of EGFR-tyrosine kinase inhibitors. Collectively, these results identify EGFR/CDKN2A co-mutation as a distinct subtype of NSCLC that shows superior sensitivity to immune checkpoint blockade and reveals a potential combined therapeutic strategy for treating this NSCLC subtype.

A real‑world study of clinical characteristics, treatment sequence and outcomes of patients with non-small cell lung cancer and EGFR exon 20 insertion mutations.

EGFR exon 20 insertion (EGFRex20ins) mutations are found in up to 4% of all patients with non-small cell lung cancer (NSCLC). These patients are often insensitive to EGFR-tyrosine kinase inhibitors (TKIs) and have worse prognosis than patients with more common EGFR mutations. In this multicenter, retrospective, real-world study, we sought to determine whether the administration of recently approved treatments that specifically target EGFRex20ins mutations could significantly improve outcomes in this patient population. We evaluated the clinical features of 41 patients diagnosed with NSCLC and EGFRex20ins mutations, their evolution, and response to treatments received across 7 hospitals in the Valencian Community, Spain, between 31st December 2012 and 31st December 2022. 32 patients (72%) developed metastatic disease, and 29 (71%) of them received oncological treatment. We found that administering a targeted therapy against EGFRex20ins mutations (amivantamab, mobocertinib and/or sunvozertinib) at some point during the course of treatment, significantly increased the median OS of metastatic patients from 8months (95% CI 0-21.7) to 30months (95% CI 11.1-48.8; Hazard ratio = 0.297, p = 0.02). Our findings contribute to the evolving standard of care for this specific population and highlight the clinical benefits of targeted cancer therapies.

Inhibitory effect of 1,4,5,6-tetrahydroxy-7,8-diprenylxanthone against NSCLC with L858R/T790M/C797S mutant EGFR

Epidermal growth factor receptor (EGFR)-activating mutations are critical factors in the development of EGFR-driven non-small-cell lung cancer (NSCLC), and molecular targeted therapies have focused on inhibiting these mutations. EGFR tyrosine kinase inhibitors (TKIs) have remarkable inhibitory effects on NSCLC with EGFR mutations. However, acquired resistance limits the clinical application of EGFR-TKIs, highlighting the need for discovery of novel therapeutic strategies. 1,4,5,6-tetrahydroxy-7,8-diprenylxanthone is a natural product derived from Garcinia xanthochymus, has shown potential anti-tumor activity, but the underlying mechanism needs further elucidation. In this study, we developed Ba/F3 and NIH/3T3 cells harboring EGFR L858R/T790M/C797S mutation, and then found that 1,4,5,6-tetrahydroxy-7,8-diprenylxanthone exerted inhibitory effects against cells with EGFR L858R/T790M/C797S mutation. Additionally, 1,4,5,6-tetrahydroxy-7,8-diprenylxanthone exhibited potent anti-tumor activity against cells harboring the triple-mutant EGFR by promoting apoptosis and inducing changes in cell cycle distribution. Furthermore, 1,4,5,6-tetrahydroxy-7,8-diprenylxanthone was found to significantly reduce tumor growth via suppressing the phosphorylation of EGFR in tumor tissues. These effects are associated with binding of 1,4,5,6-tetrahydroxy-7,8-diprenylxanthone to EGFR resulting in the suppression of extracellular signal-regulated kinase (Erk) phosphorylation. In conclusion, our results suggest that 1,4,5,6-tetrahydroxy-7,8-diprenylxanthone may be a potential novel candidate for further investigation and treatment of NSCLC with the triple-mutant EGFR.

Putative mechanisms of primary resistance to EGFR-targeted therapies: A retrospective study

BackgroundsAdvanced lung adenocarcinoma (LUAD) patient with EGFR mutations often experience resistance to first-line epidermal growth factor tyrosine kinase inhibitors (EGFR-TKIs) therapy. Nonetheless, the mechanism and biomarkers of primary resistance remain unclear. Further exploration of independent prognostic factors will help clinicians identify patients who may not respond to EGFR-TKIs and select appropriate treatment strategies. MethodsA retrospective study involving 124 patients with stage IV LUAD harboring a common sensitizing EGFR mutation (exon 19 deletion or L858R mutation) who received EGFR-TKIs as first-line therapy was performed. All participants were tested by DNA-targeted sequencing in baseline samples, and there were 19 patients with progression-free survival (PFS) ≤ 3 months (cohort 1, C1, primary resistance), 22 patients with 3 < PFS < 8 months (cohort 2, C2, poor response) without known mutations associated with resistance, and 83 patients with PFS ≥ 8 months (cohort 3, C3, normal). ResultsThe most commonly mutated genes at baseline in patients prior to treatment within the entire study population. were TP53 (65 %), MYC (19 %), CDKN2A (12 %), MUC16 (12 %) and RBM10 (12 %). The baseline characteristics, except for the proportions of patients with EGFR L858R mutation and exon 19 deletion in C1 plus C2 compared to C3 (p = 0.036), were not significantly different among the cohorts. The frequencies of PIK3C2G, STK11, EPAS1, RARA and BTG2 variation were significantly higher in C1, the primary resistance group. Multivariate Cox analysis revealed that PIK3C2G (HR 15.70 95 % CI 3.24–76.05, p < 0.001), STK11 (HR 17.04, 95 % CI 3.68–78.92, p < 0.001), EPAS1 (HR 11.99, 95 % CI 2.57–56.03, p = 0.002), and BTG2 amplification (HR 9.53, 95 % CI 1.67–54.28, p = 0.011) were significantly associated with shorter PFS. ConclusionsThe genomic landscape varies significantly among patients with LUAD, which should be considered when making personalized treatment decisions. This information could provide insights into molecular changes and their effects on clinical treatment in diverse patients with LUAD harboring sensitizing EGFR mutations.

Class I HLA Alleles are associated with an increased risk of osimertinib-induced hypersensitivity

BackgroundOsimertinib, a third-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI), shows superior lung cancer treatment efficacy. However, osimertinib-induced severe hypersensitivity, including Stevens–Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN), is frequently observed in Asian populations and hinders cancer treatment. ObjectiveWe investigated the genetic HLA predisposition and immune pathomechanism of osimertinib-induced hypersensitivity. MethodsWe enrolled 17 patients with osimertinib-induced delayed hypersensitivity (7 with severe SJS/TEN and 10 with mild maculopapular exanthema [MPE]), 98 osimertinib-tolerant subjects, and 2123 general population controls. HLA genotyping, drug-induced lymphocyte activation test (LAT), and surface plasmon resonance (SPR) assay were performed. ResultsHLA-B*51:02 was present in 83.3% of osimertinib-induced SJS/TEN patients but only in 3.3% of the general population controls (P = 2.8×10−7, Pc=6.9×10−6, odds ratio [OR]=146), and 0% of osimertinib-tolerant controls (P = 6.5×10−8, Pc=1.6×10−6, OR=707). The association of HLA-B*51:01 and HLA-A*24:02 with osimertinib-induced MPE patients, rather than with osimertinib-tolerant subjects (P = 0.002, OR=15.7 for HLA-B*51:01; P = 0.003, OR=9.5 for HLA-A*24:02), was identified as a phenotype-specific association. Granulysin—the SJS/TEN-specific cytotoxic protein—was significantly higher in SJS/TEN patients’ plasma (39.8±4.5 ng/ml, P<0.001) and in in vitro LAT (sensitivity=83.3%, P<0.01) compared to the tolerant controls. Patients with osimertinib-induced hypersensitivity appeared to tolerate alternative EGFR-TKIs. SPR results also confirmed that HLA-B*51:02 protein has a higher binding affinity for osimertinib and lower or no affinity for other EGFR-TKIs. ConclusionsHLA-B*51:02 frequently occurs in Asian populations and is strongly associated with osimertinib-induced SJS/TEN. Our findings suggest HLA-B*51:02 screening as a preemptive test to reduce osimertinib-induced severe hypersensitivity.

Monitoring of Circulating Tumor DNA and Indication of De-Escalation Adjuvant Targeted Therapy for EGFR-Mutated NSCLC After Complete Resection

IntroductionEGFR tyrosine kinase inhibitor (TKI) is the standard adjuvant treatment for patients with stages IB to IIIA EGFR-mutated NSCLC. Nevertheless, adapting this approach to include a molecular residual disease (MRD)-guided de-escalation strategy warrants further investigation. MethodsFrom January 2019 to December 2022, 71 patients with stages I to III NSCLC and EGFR (exon 19 deletion or L858R) mutations were enrolled in this observational study. A total of 375 blood samples were analyzed using the MRD_Navigator assay. Among them, 27 patients suspended EGFR TKI treatment based on undetectable MRD and were thus included in the adaptive, de-escalation group. ResultsOverall, the sensitivity of longitudinal MRD was 86.2%. Only four patients (11.8%) recurred with longitudinal undetectable MRD, indicating a negative predictive value of 88.2%. Of the patients who had detectable MRD after surgery, nine subsequently received EGFR TKI treatment, with only one (11.1%) achieving persistent circulating tumor DNA clearance post–EGFR TKI. Furthermore, 22 patients with stages IB to III disease who had previously suspended their TKI treatment based on undetectable MRD were included in the adaptive group, with an average duration of TKI 3.9 (range: 0–35.0) months. The 2-year disease-free survival rate of these 22 patients was 80.2%, and the median was not reached. Five patients (n = 5 of 22, 22.7%) had disease recurrence during the period of drug cessation but were stable under EGFR TKI treatment until the latest follow-up. Two patients remained in complete remission. ConclusionsOur initial findings underscore the potential of an adaptive, de-escalation approach to adjuvant EGFR TKIs based on circulating tumor DNA-MRD monitoring.

Synthesis, In Silico Prediction, and In Vitro Evaluation of Anti-tumor Activities of Novel 4'-Hydroxybiphenyl-4-carboxylic Acid Derivatives as EGFR Allosteric Site Inhibitors.

Allosteric inhibition of EGFR tyrosine kinase (TK) is currently among the most attractive approaches for designing and developing anti-cancer drugs to avoid chemoresistance exhibited by clinically approved ATP-competitive inhibitors. The current work aimed to synthesize new biphenyl-containing derivatives that were predicted to act as EGFR TK allosteric site inhibitors based on molecular docking studies. A new series of 4'-hydroxybiphenyl-4-carboxylic acid derivatives, including hydrazine-1-carbothioamide (S3-S6) and 1,2,4-triazole (S7-S10) derivatives, were synthesized and characterized using IR, 1HNMR, 13CNMR, and HR-mass spectroscopy. Compound S4 had a relatively high pharmacophore-fit score, indicating that it may have biological activity similar to the EGFR allosteric inhibitor reference, and it scored a relatively low ΔG against EGFR TK allosteric site, indicating a high likelihood of drug-receptor complex formation. Compound S4 was cytotoxic to the three cancer cell lines tested, particularly HCT-116 colorectal cancer cells, with an IC50 value comparable to Erlotinib. Compound S4 induced the intrinsic apoptotic pathway in HCT-116 cells by arresting them in the G2/M phase. All of the new derivatives, including S4, met the in silico requirements for EGFR allosteric inhibitory activity. Compound S4 is a promising EGFR tyrosine kinase allosteric inhibitor that warrants further research.

Afatinib and Necitumumab in EGFR-Mutant Non-Small Cell Lung Cancer with Acquired Resistance to EGFR Tyrosine Kinase Inhibitors

IntroductionAlthough tyrosine kinase inhibitors (TKIs) are effective against non-small cell lung cancer (NSCLC) harboring sensitizing epidermal growth factor receptor (EGFR) gene mutations, acquired resistance is inevitable. Preclinical studies suggest combining EGFR TKI and monoclonal antibody therapies may have activity in EGFR-mutated NSCLC that has progressed on TKI therapy alone. Therefore, we prospectively evaluated afatinib plus necitumumab in patients with EGFR-mutated NSCLC. MethodsThis was a phase I dose-escalation, dose-expansion trial assessing the safety and efficacy of afatinib plus necitumumab. Patients had advanced or metastatic EGFR-mutated NSCLC with progression after: (1) first-generation TKI if T790M-negative; (2) subsequent line third-generation TKI if T790M-positive; or (3) third-generation TKI in the first-line setting. Dose-escalation followed a 3+3 design. The primary endpoint of dose-expansion was objective response rate (ORR). ResultsA total of 22 patients with EGFR-mutated NSCLC were enrolled. The maximum tolerated dose (MTD) was afatinib 40 mg oral daily plus necitumumab 600 mg intravenous on days 1 and 15 every 28 days. There were no Grade 4-5 adverse events observed, and seven patients (32%) experienced Grade 3 treatment-related adverse events (3 rash; 1 each oral mucositis, diarrhea, headache, and ventricular arrhythmia and tachycardia). In the entire cohort, there were no responses observed, the median progression-free survival (PFS) was 1.8 months, and the disease control rate (DCR) was 36% but varied between subgroups. ConclusionsAfatinib plus necitumumab was safe but showed limited activity in patients with EGFR-mutated NSCLC. Biomarker studies may identify patient subgroups that are more likely to benefit.

Clinical characteristics and prognostic factors of epidermal growth factor receptor-mutated non-small cell lung cancer transformed into small-cell lung cancer after treatment

Objective: To analyze the clinical characteristics and prognostic factors of non-small cell lung cancer (NSCLC) patients with sensitive epidermal growth factor receptor (EGFR) mutations who developed small cell lung cancer (SCLC) transformation after treatment with EGFR tyrosine kinase inhibitors (TKI). Methods: We conducted a retrospective collection of clinical data for 21 patients with advanced EGFR mutant NSCLC who developed SCLC transformation after EGFR-TKI treatment at Beijing Chest Hospital, Capital Medical University from January 2015 to December 2021. The clinical characteristics were summarized and the prognosis analysis was conducted. Patients were followed up until February 2024. The efficacy was evaluated using Solid Tumor Response Evaluation Criteria, and survival curves were plotted using the Kaplan-Meier method, and the log-rank test was used to compare the differences in survival time (OS) between limited stage and extensive stage in transformed SCLC patients. Cox proportional hazards model was used to analyze the influencing factors of survival after SCLC transformation. Results: Among the 21 patients, there were 5 males and 16 females, with an age range of 33-74 years old [(58.9±2.6) years old]. All 21 patients were adenocarcinoma with sensitive EGFR mutations. There were 18 cases (85.7%) with EGFR gene 19del mutation, including 1 case of 19del+anaplastic lymphoma kinase (ALK) mutation, and 3 cases of L858R mutation. Among the transformed SCLC, there were 11 cases of pure SCLC and 10 cases of mixed SCLC (coexisting of adenocarcinoma and small cell carcinoma components). The median time from diagnosis of NSCLC to SCLC transformation was 12.0 months (95%CI: 7.6-16.3 months). Among the 21 cases of SCLC transformation, there were 13 cases with the extensive stage and 8 cases with the limited stage. Among them, 16 patients received systemic chemotherapy based on etoposide, of which 13 cases could be evaluated for efficacy, 11 cases could be calculated for PFS. Five cases had partial remission, 5 cases were stable, 3 cases had disease progression, and 3 cases cloud not be evaluated. The median progression free survival time (PFS) was 4.8 months (95%CI: 2.8-6.8 months). The median survival time (OS) after SCLC transformation in 21 patients was 10.6 months (95%CI: 7.0-14.2 months), with a median OS of 8.8 months (95%CI: 6.3-11.4 months) for patients with the extensive stage and 27.5 months (95%CI: 9.6-34.4 months) for patients with the limited stage, with statistically significant differences (P=0.002). Cox proportional hazards model analysis showed that the limited stage after SCLC transformation was a protective factor for OS (HR=0.32, 95%CI: 0.12-0.73, P=0.010). The median OS of 21 patients from the diagnosis of lung cancer was 24.9 months (95%CI: 13.0-36.7 months). Conclusions: NSCLC patients with SCLC transformation are all adenocarcinomas, and the proportion of EGFR19del mutations is relatively high. After SCLC transformation, the standard chemotherapy regimen for SCLC is generally used for treatment. The OS after SCLC transformation is related to the stage, and the prognosis is better in the limited stage.

Biochemical analysis of EGFR exon20 insertion variants insASV and insSVD and their inhibitor sensitivity

Somatic mutations in the epidermal growth factor receptor (EGFR) are a major cause of non-small cell lung cancer. Among these structurally diverse alterations, exon 20 insertions represent a unique subset that rarely respond to EGFR tyrosine kinase inhibitors (TKIs). Therefore, there is a significant need to develop inhibitors that are active against this class of activating mutations. Here, we conducted biochemical analysis of the two most frequent exon 20 insertion variants, V769_D770insASV (insASV) and D770_N771insSVD (insSVD) to better understand their drug sensitivity and resistance. From kinetic studies, we found that EGFR insASV and insSVD are similarly active, but have lower Km, ATP values compared to the L858R variant, which contributes to their lack of sensitivity to 1st-3rd generation EGFR TKIs. Biochemical, structural, and cellular studies of a diverse panel of EGFR inhibitors revealed that the more recently developed compounds BAY-568, TAS6417, and TAK-788 inhibit EGFR insASV and insSVD in a mutant-selective manner, with BAY-568 being the most potent and selective versus wild-type (WT) EGFR. Cocrystal structures with WT EGFR reveal the binding modes of each of these inhibitors and of poziotinib, a potent but not mutantselective inhibitor, and together they define interactions shared by the mutant-selective agents. Collectively, our results show that these exon20 insertion variants are not inherently inhibitor resistant, rather they differ in their drug sensitivity from WT EGFR. However, they are similar to each other, indicating that a single inhibitor should be effective for several of the diverse exon 20 insertion variants.

Cytochalasin H enhances sensitivity to gefitinib in non-small-cell lung cancer cells through inhibiting EGFR activation and PD-L1 expression

In our previous study, we have isolated cytochalasin H (CyH) from endophytic fungus derived from mangrove plant and found that CyH inhibited the proliferation of non-small cell lung cancer (NSCLC) cells. Recently, epidermal growth factor receptor (EGFR) activation and programmed cell death 1 ligand (PD-L1) expression have been demonstrated to mediate NSCLC resistance to gefitinib, first-generation EGFR tyrosine kinase inhibitor (EGFR-TKI). Here, we further investigated the effect of CyH on EGFR activation, PD-L1 expression, and gefitinib sensitivity in NSCLC cell lines, A549 (wild-type EGFR), HCC827 (EGFR mutation), and NCI-H1975 (dual EGFR mutations and acquired gefitinib resistance) and animal model. Our results showed that CyH significantly inhibited EGFR activation and PD-L1 expression in NSCLC cells. Additionally, CyH dramatically promoted the inhibitory effect of gefitinib on the proliferation of A549 and HCC827 cells, and enhanced the sensitivity to gefitinib in NCI-H1975 cells. Moreover, CyH increased the inhibitory effect of gefitinib on EGFR activation and PD-L1 expression in HCC827 and NCI-H1975 cells. Animal experiments further demonstrated that CyH significantly promoted the inhibitory effect of gefitinib on the growth of NSCLC and the expression of Ki-67, p-EGFR, and PD-L1 in NCI-H1975 NSCLC xenograft tumors of nude mice. Furthermore, CyH inhibited the activation of JAK3/STAT signaling pathway. Taken together, our findings suggest that CyH promotes the sensitivity to gefitinib in NSCLC cells through the inhibition of EGFR activation and PD-L1 expression.