Genotypic and histological evolution of lung cancers acquiring resistance to EGFR inhibitors

PPP3CB overexpression mediates EGFR TKI resistance in lung tumors via calcineurin/MEK/ERK signaling

Despite initial high response rates to first-line EGFR TKI, all non-small-cell lung cancer (NSCLC) with EGFR-activating mutation will ultimately develop resistance to treatment. Identification of resistance mechanisms is critical to adapt treatment and improve patient outcomes. Here, we show that a PPP3CB transcript that encodes full-length catalytic subunit 2B of calcineurin accumulates in EGFR-mutant NSCLC cells with acquired resistance against different EGFR TKIs and in post-progression biopsies of NSCLC patients treated with EGFR TKIs. Neutralization of PPP3CB by siRNA or inactivation of calcineurin by cyclosporin A induces apoptosis in resistant cells treated with EGFR TKIs. Mechanistically, EGFR TKIs increase the cytosolic level of calcium and trigger activation of a calcineurin/MEK/ERK pathway that prevents apoptosis. Combining EGFR, calcineurin, and MEK inhibitors overcomes resistance to EGFR TKI in both in vitro and in vivo models. Our results identify PPP3CB overexpression as a new mechanism of acquired resistance to EGFR TKIs, and provide a promising therapeutic approach for NSCLC patients that progress under TKI treatment.

The clinical features and prognostic implications of the co-mutated TP53 gene in advanced non-small cell lung cancer

BACKGROUND

TP53 is a frequently mutated oncogene within non-small cell lung cancer (NSCLC). However, the clinical and prognostic significance of co-mutations in TP53 in patients with advanced NSCLC has not been fully elucidated.

METHODS

A total of 174 patients with advanced NSCLC were enrolled in this study. All patients were subjected to sequencing analysis of tumor-related genes and information such as PD-L1 expression, TMB, and co-mutation changes were collected. Patients were categorized into TP53 mutant and TP53 wild-type groups according to their TP53 mutation status and then statistically analyzed.

RESULTS

TP53 mutations were the most common among all patients, accounting for 56.32%, followed by epidermal growth factor receptor mutations at 48.27%. The most common mutation sites in the TP53 mutation group were exons 5-8.TP53 mutations were significantly associated with PD-L1 and TMB levels. Univariate Cox analysis showed that gender and EGFR mutation affected the prognosis of TP53-mutated NSCLC patients, and multivariate Cox regression analysis identified EGFR mutation as an independent risk factor. The OS of NSCLC patients in the TP53 mutation group was significantly shorter than that of the TP53wt group. Survival curves in the TP53/EGFR combined mutation group showed that patients with combined EGFR mutation had a lower survival rate.

DISCUSSION

TP53 mutations are associated with different clinical indicators and have important implications in clinical treatment. TP53 is a poor prognostic factor for NSCLC patients, and TP53/EGFR co-mutation will affect the survival time of patients. TP53/EGFR co-mutation may be a new prognostic marker for NSCLC.

Neuroendocrine Differentiation in Prostate Cancer Requires ASCL1

Most patients with prostate adenocarcinoma develop resistance to therapies targeting the androgen receptor (AR). Consequently, a portion of these patients develop AR-independent neuroendocrine (NE) prostate cancer (NEPC), a rapidly progressing cancer with limited therapies and poor survival outcomes. Current research to understand the progression to NEPC suggests a model of lineage plasticity whereby AR-dependent luminal-like tumors progress toward an AR-independent NEPC state. Genetic analysis of human NEPC identified frequent loss of RB1 and TP53, and the loss of both genes in experimental models mediates the transition to a NE lineage. Transcriptomics studies have shown that lineage transcription factors ASCL1 and NEUROD1 are present in NEPC. In this study, we modeled the progression of prostate adenocarcinoma to NEPC by establishing prostate organoids and subsequently generating subcutaneous allograft tumors from genetically engineered mouse models harboring Cre-induced loss of Rb1 and Trp53 with Myc overexpression (RPM). These tumors were heterogeneous and displayed adenocarcinoma, squamous, and NE features. ASCL1 and NEUROD1 were expressed within NE-defined regions, with ASCL1 being predominant. Genetic loss of Ascl1 in this model did not decrease tumor incidence, growth, or metastasis; however, there was a notable decrease in NE identity and an increase in basal-like identity. This study provides an in vivo model to study progression to NEPC and establishes the requirement for ASCL1 in driving NE differentiation in prostate cancer. Significance: Modeling lineage transitions in prostate cancer and testing dependencies of lineage transcription factors have therapeutic implications, given the emergence of treatment-resistant, aggressive forms of neuroendocrine prostate cancer. See related commentary by McQuillen and Brady, p. 3499.

Histological transformation in lung adenocarcinoma: Insights of mechanisms and therapeutic windows

Histological transformation from lung adenocarcinoma (ADC) to small cell lung carcinoma (SCLC), large cell neuroendocrine carcinoma (LCNEC), squamous cell carcinoma (SCC), and sarcomatoid carcinoma (PSC) after targeted therapies is recognized as a mechanism of resistance in ADC treatments. Patients with transformed lung cancer typically experience a poor prognosis and short survival time. However, effective treatment options for these patients are currently lacking. Therefore, understanding the mechanisms underlying histological transformation is crucial for the development of effective therapies. Hypotheses including intratumoral heterogeneity, cancer stem cells, and alteration of suppressor genes have been proposed to explain the mechanism of histological transformation. In this review, we provide a comprehensive overview of the known molecular features and signaling pathways of transformed tumors, and summarized potential therapies based on previous findings.

Detailed characterization of combination treatment with MET inhibitor plus EGFR inhibitor in EGFR-mutant and MET-amplified non-small cell lung cancer

Background

Detailed clinical data about combination treatment with MET inhibitor (METi) and EGFR inhibitor (EGFRi) is lacking in patients with EGFR-mutant, MET-amplified, and EGFRi-resistant non-small cell lung cancer (NSCLC). This study aimed to report longitudinal data on the efficacy and safety of this combination treatment.

Methods

We retrospectively analyzed 44 patients with advanced EGFR-mutant and MET-amplified NSCLC who were treated with any types of METi plus EGFRi after progression with EGFRi at the National Cancer Center Hospital. Longitudinal clinicogenomic data and plasma circulating tumor DNA (ctDNA) data were collected.

Results

The overall response rate was 74.4% and median progression-free survival (PFS) was 5.3 months [95% confidence interval (CI): 3.3-7.3]. Twenty-three patients (52.3%) required either or both treatment discontinuation due to adverse effects. The main cause of discontinuation was pneumonitis (69.2%). There was no significant difference in the PFS of patients with or without METi discontinuation [hazard ratio (HR), 0.93; 95% CI: 0.49-1.78; P=0.83]. Median clearance time of MET amplification in plasma ctDNA was measured as 63 days. Patients who stopped METi within 63 days of initiation showed poorer PFS compared to those who discontinued after (HR, 2.78; 95% CI: 1.00-7.75; P=0.050). Diverse resistance mechanisms including on-target mutations in MET (D1246H) and EGFR (C797S or T790M) were detected in 14 patients. One MET D1246H-mutant case and one EGFR C797S-mutant case responded to sitravatinib and amivantamab, respectively.

Conclusions

A combination of METi and EGFRi showed a promising anti-tumor effect in advanced EGFR-mutant and MET-amplified NSCLC. Pneumonitis was the main adverse effects leading to treatment discontinuation. Early discontinuation of METi negatively affected the survival outcomes.

Expression of the non-coding RNA nc886 facilitates the development of tyrosine kinase inhibitor resistance in EGFR-mutated non-small-cell lung cancer cells

Treatment of non-small-cell lung cancer (NSCLC) patients possessing EGFR-activating mutations with tyrosine kinase inhibitors (TKIs) can confer an initial promising response. However, TKI resistance inevitably arises. Numerous TKI resistance mechanisms are identified including EGFR secondary mutations, bypass receptor tyrosine kinase (RTK) signaling, and cellular transition e.g. epithelial-mesenchymal transition (EMT). To increase the knowledge of TKI resistance we performed an epigenetic screen to identify small non-coding (nc) genes with DNA methylation alterations in HCC827 NSCLC EGFR-mutated cells with acquired TKI resistance. We analyzed Infinium Methylation EPIC 850K Array data for DNA methylation changes present in both TKI-resistant HCC827 cells with EMT and MET-amplification. Hereby, we identified that the polymorphic maternal imprinted gene nc886 (vtRNA2-1) has a decrease in promoter DNA methylation in TKI-resistant cells. This epigenetic change was associated with an increase in the expression of nc886. The induction of EMT did not affect nc886 expression. CRISPR/Cas9-mediated distortion of the nc886 sequence increased the sensitivity of HCC827 cells towards TKI. Finally, nc886 sequence distortion hindered MET RTK activation and instead was EMT the endpoint TKI resistance mechanism. In conclusion, the expression of nc886 contributes to TKI resistance in the HCC827 NSCLC cell line by supporting cell survival and selection of the endpoint TKI resistance mechanism. We propose DNA methylation and expression changes for nc886 to constitute a novel TKI resistance contributing mechanism in NSCLC.

The neuroendocrine transition in prostate cancer is dynamic and dependent on ASCL1

Lineage plasticity is a hallmark of cancer progression that impacts therapy outcomes, yet the mechanisms mediating this process remain unclear. Here, we introduce a versatile in vivo platform to interrogate neuroendocrine lineage transformation throughout prostate cancer progression. Transplanted mouse prostate organoids with human-relevant driver mutations (Rb1-/-; Trp53-/-; cMyc+ or Pten-/-; Trp53-/-; cMyc+) develop adenocarcinomas, but only those with Rb1 deletion advance to aggressive, ASCL1+ neuroendocrine prostate cancer (NEPC) resistant to androgen receptor signaling inhibitors. Notably, this transition requires an in vivo microenvironment not replicated by conventional organoid culture. Using multiplexed immunofluorescence and spatial transcriptomics, we reveal that ASCL1+ cells arise from KRT8+ luminal cells, progressing into transcriptionally heterogeneous ASCL1+;KRT8- NEPC. Ascl1 loss in established NEPC causes transient regression followed by recurrence, but its deletion before transplantation abrogates lineage plasticity, resulting in castration-sensitive adenocarcinomas. This dynamic model highlights the importance of therapy timing and offers a platform to identify additional lineage plasticity drivers.

Cancer Epithelial Cells Participate in the Self-Organization of Lung Tumor Spheroids: A Morphological Approach

INTRODUCTION/AIMS

The tumor microenvironment is known to play an important role in tumor progression. However, the specific mechanisms underlying this process are still not known in detail and more research is needed on the elements that control tumor progression in lung cancer. In this work, we aimed to investigate the involvement of epithelial and stromal cancer cells in growth, cell migration, and epithelial-to-mesenchymal transition (EMT) in a 3D in vitro model consisting of cell spheroids cultured in a type I collagen scaffold.

METHODS

Spheroids were manufactured using different combinations of epithelial cells, particularly H460 and H1792 cell lines, with cancer-associated fibroblasts and normal fibroblasts, both isolated from adenocarcinoma patients. We evaluated the morphology of the spheroids by analysis of F-actin and pankeratin with confocal microscopy. We determined the ultrastructure of cells in the spheroids by transmission electron microscopy and the expression of CDH1, CDH2, and VIM by RT-PCR.

RESULTS

We observed that, on the one hand, the type of epithelial cell influences the morphology of spheroids. Stromal cells stimulated spheroid growth and cell dissemination through the collagen matrix, either alone or organized in branches with a nucleus of epithelial cells preceded by fibroblast cells. They also induced the appearance of new cell groups in the scaffold and the presence of EMT markers.

CONCLUSION

The results presented here indicate the participation of both epithelial and stromal cells in the control of spheroid self-organization. The experimental model proposed here, although preliminary, is useful for the study of some aspects related to tumor progression in lung cancer.

Amplifying mutational profiling of extracellular vesicle mRNA with SCOPE

Sequencing of messenger RNA (mRNA) found in extracellular vesicles (EVs) in liquid biopsies can provide clinical information such as somatic mutations, resistance profiles and tumor recurrence. Despite this, EV mRNA remains underused due to its low abundance in liquid biopsies, and large sample volumes or specialized techniques for analysis are required. Here we introduce Self-amplified and CRISPR-aided Operation to Profile EVs (SCOPE), a platform for EV mRNA detection. SCOPE leverages CRISPR-mediated recognition of target RNA using Cas13 to initiate replication and signal amplification, achieving a sub-attomolar detection limit while maintaining single-nucleotide resolution. As a proof of concept, we designed probes for key mutations in KRAS, BRAF, EGFR and IDH1 genes, optimized protocols for single-pot assays and implemented an automated device for multi-sample detection. We validated SCOPE's ability to detect early-stage lung cancer in animal models, monitored tumor mutational burden in patients with colorectal cancer and stratified patients with glioblastoma. SCOPE can expedite readouts, augmenting the clinical use of EVs in precision oncology.

Mechanism exploration and model construction for small cell transformation in EGFR-mutant lung adenocarcinomas

Small-cell lung cancer (SCLC) transformation accounts for 3-14% of resistance in EGFR-TKI relapsed lung adenocarcinomas (LUADs), with unknown molecular mechanisms and optimal treatment strategies. We performed transcriptomic analyses (including bulk and spatial transcriptomics) and multiplex immunofluorescence on pre-treated samples from LUADs without transformation after EGFR-TKI treatment (LUAD-NT), primary SCLCs (SCLC-P) and LUADs with transformation after EGFR-TKI treatment (before transformation: LUAD-BT; after transformation: SCLC-AT). Our study found that LUAD-BT exhibited potential transcriptomic characteristics for transformation compared with LUAD-NT. We identified several pathways that shifted during transformation, and the transformation might be promoted by epigenetic alterations (such as HDAC10, HDAC1, DNMT3A) within the tumor cells instead of within the tumor microenvironment. For druggable pathways, transformed-SCLC were proved to be less dependent on EGF signaling but more relied on FGF signaling, while VEGF-VEGFR pathway remained active, indicating potential treatments after transformation. We also found transformed-SCLC showed an immuno-exhausted status which was associated with the duration of EGFR-TKI before transformation. Besides, SCLC-AT exhibited distinct molecular subtypes from SCLC-P. Moreover, we constructed an ideal 4-marker model based on transcriptomic and IHC data to predict SCLC transformation, which obtained a sensitivity of 100% and 87.5%, a specificity of 95.7% and 100% in the training and test cohorts, respectively. We provided insights into the molecular mechanisms of SCLC transformation and the differences between SCLC-AT and SCLC-P, which might shed light on prevention strategies and subsequent therapeutic strategies for SCLC transformation in the future.

Clinical Management in NSCLC Patients With EGFR Mutation After Osimertinib Progression With Unknown Resistance Mechanisms

BACKGROUND

Osimertinib is approved as a standard treatment for non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutation by FDA. However, the mechanisms of resistance for nearly half of patients after osimertinib progression are still unknown, and the optimal therapies for these patients are still controversial. In this retrospective study, we compared efficacy and safety between immunotherapy + chemotherapy, chemotherapy alone, and osimertinib + bevacizumab in NSCLC patients after osimertinib progression with unknown resistance mechanisms.

METHODS

Advanced NSCLC patients with unknown resistance mechanisms after osimertinib progression were retrospectively reviewed and divided into immunotherapy + chemotherapy, chemotherapy alone, and osimertinib + bevacizumab treatment groups according to the treatment they received after osimertinib progression. Clinicopathological features, objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) were compared between groups.

RESULTS

A total of 121 patients were enrolled in this study, 22 in the immunotherapy + chemotherapy group, 72 in the chemotherapy group, and 27 in the osimertinib + bevacizumab group. The ORR was much higher in the immunotherapy + chemotherapy group compared with chemotherapy or osimertinib + bevacizumab group (55.56% vs. 14.81% vs. 0% in patients after progression on 1st line osimertinib treatment; 30.77% vs. 6.67% vs. 13.33% in patients after progression on 2nd/3rd line osimertinib treatment). Median PFS was also significantly longer in the immunotherapy + chemotherapy group compared with other groups (8.2 months vs. 4.0 months vs. 6.0 months in all patients, p = 0.0066). The median OS did not reach remarkable difference among groups, although osimertinib + bevacizumab group had a numerically longer median OS (37.0 months vs. 37.0 months vs. 47.6 months in all patients, p = 0.6357). Compared with immunotherapy + chemotherapy and chemotherapy, treatment-related adverse events (AEs) of osimertinib + bevacizumab were milder, especially in AEs related to gastrointestinal and bone marrow suppression.

CONCLUSION

Our study provides clinical evidence that NSCLC patients after osimertinib progression with unknown resistance mechanisms may benefit from immunotherapy + chemotherapy, with higher ORR and longer PFS compared with osimertinib + bevacizumab or chemotherapy groups. Osimertinib + bevacizumab treatment was also an optional option for patients because OS was numerically longer and safer in this group.

Inhibition of DDR1 promotes ferroptosis and overcomes gefitinib resistance in non-small cell lung cancer

Gefitinib is an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), which serves the critical pillar for the treatment of non-small cell lung cancer (NSCLC). However, the acquired resistance remains a challenge for its clinical application, for which, practical strategies to reverse gefitinib resistance in NSCLC are necessary. Ferroptosis, a programmed cell death driven by ferritin-dependent lipid peroxidation, involves in NSCLC progression and related chemoresistance. In our previous work, the self-synthesised EGFR inhibitor Yfq07 (N4, N6-disubstituted pyrimidine-4,6-diamine derivatives) displayed a considerable inhibitory effect on NSCLC both in vitro and in vivo. Herein, we observed that Yfq07 suppressed the proliferation of PC-9GR and HCC827GR cells, two gefitinib resistance NSCLC cell lines. Mechanically, Yfq07 inhibited the phosphorylation of the Discoidin Domain Receptor 1 (DDR1), a receptor tyrosine kinase (RTK) highly expressed in multiple cancers, accompanied by downregulated miR-3648 and upregulated SOCS2. Inhibition or knockdown of DDR1 suppressed the proliferation, migration, and invasion of gefitinib-resistant NSCLC cells, and on the other hand, also downregulated miR-3648 and promoted SOCS2 expression. More specifically, miR-3648 targeted the 3'UTR segment of SOCS2 mRNA and thus affecting the P-ERK signalling pathway to regulate the malignant behaviors of gefitinib-resistant NSCLC cells. Furthermore, Yfq07 also indirectly induced the ferroptosis of gefitinib-resistant NSCLC cells via SOCS2 triggered inhibition of xCT-GPX4 pathway. In conclusion, our study indicates that DDR1 inhibitor Yfq07 promotes ferroptosis and reverses gefitinib-resistance of NSCLC through DDR1-miR-3648-SOCS2 signalling pathway, which provides insights for targeted therapy of gefitinib-resistant NSCLC and drug developments targeting ferroptosis.

EGFR mutations in patients with lung adenocarcinoma and malignant pleural effusion: a propensity score-matched analysis of a single-center database

Background

Malignant pleural effusion (MPE) is associated with poor prognosis in patients with advanced lung adenocarcinoma (LUAD), and abnormal activation of epidermal growth factor receptor (EGFR) plays a crucial role in the development of LUAD. This study aimed to investigate the correlation between EGFR mutations and the occurrence of MPE in patients with LUAD and evaluate the effect of EGFR mutations on the prognosis of patients with LUAD with MPE.

Methods

A case-control study design was adopted that included patients pathologically diagnosed with LUAD. Clinical data were collected, and patients were divided into the MPE group and the non-MPE (N-MPE) group based on the presence of MPE. Propensity score matching (PSM) was used to control for confounding factors. The correlation between EGFR mutations and the occurrence of MPE in LUAD was initially examined. Additionally, various factors affecting the overall survival (OS) of patients with LUAD and MPE were evaluated.

Results

A total of 849 patients were included in the study. After 1:2 PSM, there were 180 patients in the MPE group and 360 in the N-MPE group. The EGFR mutation rate was significantly higher in the MPE group compared to the N-MPE group [62.7% vs. 50.2%; odds ratio (OR) =1.668; P=0.006]. This difference was primarily attributed to the T790M mutation (8.3% vs. 1.3%; OR =8.015; P<0.001), but no significant differences observed in other mutation sites between the groups. Further evaluation of factors affecting OS in patients with LUAD and MPE revealed that EGFR mutation was an independent protective factor for OS [hazard ratio (HR) 0.662, 95% CI: 0.456-0.962; P=0.03]. For patients with LUAD, MPE, and EGFR mutations, treatment with third-generation EGFR-tyrosine kinase inhibitors (TKIs) alone (HR 0.466, 95% CI: 0.233-0.930; P=0.03) or sequential first- and third-generation EGFR-TKIs (HR 0.385, 95% CI: 0.219-0.676; P=0.001) was associated with better median OS compared to first-generation EGFR-TKIs alone (first-generation EGFR-TKIs: 35 months, 95% CI: 28.4-41.6; third-generation EGFR-TKIs: 50 months, 95% CI: 37.3-62.7; sequential first- and third-generation EGFR-TKIs: 51 months, 95% CI: 45.6-56.4; P<0.001).

Conclusions

This study found there to be a positive correlation between EGFR mutations, particularly the T790M mutation, and MPE in patients with LUAD. EGFR mutation was associated with improved OS in patients with LUAD and MPE. For patients with LUAD, MPE, and EGFR mutations, sequential treatment with first- and third-generation EGFR-TKIs or third-generation EGFR-TKIs alone is recommended, as these regimens provide significant benefit to OS.

Tumor Cell Spatial Organization Directs EGFR/RAS/RAF Pathway Primary Therapy Resistance through YAP Signaling

Non-small cell lung cancers (NSCLC) harboring common mutations in EGFR and KRAS characteristically respond transiently to targeted therapies against those mutations, but invariably, tumors recur and progress. Resistance often emerges through mutations in the therapeutic target or activation of alternative signaling pathways. Mechanisms of acute tumor cell resistance to initial EGFR (EGFRi) or KRASG12C (G12Ci) pathway inhibition remain poorly understood. Our study reveals that acute response to EGFR/RAS/RAF-pathway inhibition is spatial and culture context specific. In vivo, EGFR mutant tumor xenografts shrink by > 90% following acute EGFRi therapy, and residual tumor cells are associated with dense stroma and have increased nuclear YAP. Interestingly, in vitro EGFRi induced cell cycle arrest in NSCLC cells grown in monolayer, while 3D spheroids preferentially die upon inhibitor treatment. We find differential YAP nuclear localization and activity, driven by the distinct culture conditions, as a common resistance mechanism for selective EGFR/KRAS/BRAF pathway therapies. Forced expression of the YAPS127A mutant partially protects cells from EGFR-mediated cell death in spheroid culture. These studies identify YAP activation in monolayer culture as a non-genetic mechanism of acute EGFR/KRAS/BRAF therapy resistance, highlighting that monolayer vs spheroid cell culture systems can model distinct stages of patient cancer progression.

Non-small-cell lung cancer

Non-small-cell lung cancer (NSCLC) is one of the most frequent cancer types and is responsible for the majority of cancer-related deaths worldwide. The management of NSCLC has improved considerably, especially in the past 10 years. The systematic screening of populations at risk with low-dose CT, the implementation of novel surgical and radiotherapeutic techniques and a deeper biological understanding of NSCLC that has led to innovative systemic treatment options have improved the prognosis of patients with NSCLC. In non-metastatic NSCLC, the combination of various perioperative strategies and adjuvant immunotherapy in locally advanced disease seem to enhance cure rates. In metastatic NSCLC, the implementation of novel drugs might prolong disease control together with preserving quality of life. The further development of predictive clinical and genetic markers will be essential for the next steps in individualized treatment concepts.

Deciphering the Dynamics of EGFR-TKI Resistance in Lung Cancer: Insights from Bibliometric Analysis

Background

EGFR-TKI resistance poses a significant challenge in the treatment landscape of non-small cell lung cancer (NSCLC), prompting extensive research into mechanisms and therapeutic strategies. In this study, we conduct a bibliometric analysis to elucidate evolving research hotspots and trends in EGFR-TKI resistance, offering insights for clinical interventions and scientific inquiries.

Methods

Publications spanning from 1996 to 2024, focusing on EGFR-TKI resistance in NSCLC, were sourced from the Web of Science Core Collection. Utilizing VOSviewer 1.6.19, CiteSpace 6.2. R2, and Scimago Graphica 1.0.35, we analyzed these articles to identify countries/regions and institutions, Journals, publications, key contributors, collaborations, and emerging topics.

Results

An analysis of 8051 articles by 38,215 researchers from 86 countries shows growing interest in EGFR-TKI resistance mechanisms. Since 1996, publications have steadily increased, surpassing 500 per year after 2016, with a sharp rise in citations. Research articles make up 84% of publications, emphasizing scholarly focus. Global collaboration, especially among researchers in China, the US, and Japan, is strong. Leading institutions like Dana-Farber and Harvard, along with journals such as "Lung Cancer", are key in sharing findings. Professors Yi-Long Wu and William Pao are prominent contributors. Keyword analysis reveals core themes, including first-generation EGFR-TKIs, emerging agents like osimertinib, and research on the T790M mutation.

Conclusion

EGFR-TKI resistance remains a critical issue in NSCLC treatment, driving ongoing research efforts worldwide. Focusing future research on clear identification of resistance mechanisms will guide post-resistance treatment strategies, necessitating further exploration, alongside the validation of emerging drugs through clinical trials. Moreover, "chemo+" treatments following EGFR-TKI resistance require more clinical data and real-world evidence for assessing safety and patient outcomes. As research advances, a multidisciplinary approach will be key to overcoming these challenges. Continued innovation in treatment could greatly enhance patient survival and quality of life.

Transferrin receptor targeting chimeras for membrane protein degradation

Cancer cells require high levels of iron for rapid proliferation, leading to significant upregulation of cell-surface transferrin receptor 1 (TfR1), which mediates iron uptake by binding to the iron-carrying protein transferrin1-3. Leveraging this phenomenon and the fast endocytosis rate of TfR1 (refs. 4,5), we developed transferrin receptor targeting chimeras (TransTACs), a heterobispecific antibody modality for membrane protein degradation. TransTACs are engineered to drive rapid co-internalization of a target protein of interest and TfR1 from the cell surface, and to enable target protein entry into the lysosomal degradation pathway. We show that TransTACs can efficiently degrade a diverse range of single-pass, multi-pass, native or synthetic membrane proteins, including epidermal growth factor receptor, programmed cell death 1 ligand 1, cluster of differentiation 20 and chimeric antigen receptor. In example applications, TransTACs enabled the reversible control of human primary chimeric antigen receptor T cells and the targeting of drug-resistant epidermal growth factor receptor-driven lung cancer with the exon 19 deletion/T790M/C797S mutations in a mouse xenograft model. TransTACs represent a promising new family of bifunctional antibodies for precise manipulation of membrane proteins and targeted cancer therapy.

Combined use of radiotherapy and tyrosine kinase inhibitors in the management of metastatic non-small cell lung cancer: A literature review

The approval of tyrosine kinase inhibitors (TKIs) as first-line agents has revolutionised treatment of patients diagnosed with advanced non-small cell lung cancer (NSCLC) harboring targetable mutations, adding substantial overall survival (OS) benefit, compared to chemotherapy. However, the efficacy of these agents is inevitably diminished at a point in the disease course, either because of cellular resistance-mechanisms or due to affected pharmacokinetics, like low-central nervous system penetration. The aim of this article is to review existing evidence on the combined use of EGFR (epidermal growth factor)- or ALK (anaplastic lymphoma kinase)-specific TKIs and radiotherapy (RT) in advanced NSCLC setting, as an attempt to delay or overcome TKI-resistance and thus, to expand the time period during which patients derive benefit from a given line of targeted therapy. At present, combining RT with EGFR- or ALK-TKIs in the management of advanced, oncodriver-mutated NSCLC has shown quite promising results, with regards to PFS and OS, rendering prolongation of the TKI-derived benefit feasible, with generally tolerable toxicity. Future studies to confirm the observed efficacy and clarify possible safety issues as well as the appropriate treatment sequence and target volumes are needed, especially in the rapidly-evolving era of newer-generation TKIs.

A bispecific antibody targeting EGFR and AXL delays resistance to osimertinib

Activating EGFR (epidermal growth factor receptor) mutations can be inhibited by specific tyrosine kinase inhibitors (TKIs), which have changed the landscape of lung cancer therapy. However, due to secondary mutations and bypass receptors, such as AXL (AXL receptor tyrosine kinase), drug resistance eventually emerges in most patients treated with the first-, second-, or third-generation TKIs (e.g., osimertinib). To inhibit AXL and resistance to osimertinib, we compare two anti-AXL drugs, an antibody (mAb654) and a TKI (bemcentinib). While no pair of osimertinib and an anti-AXL drug is able to prevent relapses, triplets combining osimertinib, cetuximab (an anti-EGFR antibody), and either anti-AXL drug are initially effective. However, longer monitoring uncovers superiority of the mAb654-containing triplet, possibly due to induction of receptor endocytosis, activation of immune mechanisms, or disabling intrinsic mutators. Hence, we constructed a bispecific antibody that engages both AXL and EGFR. When combined with osimertinib, the bispecific antibody consistently inhibits tumor relapses, which warrants clinical trials.

Defective N-glycosylation of IL6 induces metastasis and tyrosine kinase inhibitor resistance in lung cancer

The IL6-GP130-STAT3 pathway facilitates lung cancer progression and resistance to tyrosine kinase inhibitors. Although glycosylation alters the stability of GP130, its effect on the ligand IL6 remains unclear. We herein find that N-glycosylated IL6, especially at Asn73, primarily stimulates JAK-STAT3 signaling and prolongs STAT3 phosphorylation, whereas N-glycosylation-defective IL6 (deNG-IL6) induces shortened STAT3 activation and alters the downstream signaling preference for the SRC-YAP-SOX2 axis. This signaling shift induces epithelial-mesenchymal transition (EMT) and migration in vitro and metastasis in vivo, which are suppressed by targeted inhibitors and shRNAs against SRC, YAP, and SOX2. Osimertinib-resistant lung cancer cells secrete a large amount of deNG-IL6 through reduced N-glycosyltransferase gene expression, leading to clear SRC-YAP activation. deNG-IL6 contributes to drug resistance, as confirmed by in silico analysis of cellular and clinical transcriptomes and signal expression in patient specimens. Therefore, the N-glycosylation status of IL6 not only affects cell behaviors but also shows promise in monitoring the dynamics of lung cancer evolution.

Detecting Small Cell Transformation in Patients with Advanced EGFR Mutant Lung Adenocarcinoma through Epigenomic cfDNA Profiling

PURPOSE

Histologic transformation to small cell lung cancer (SCLC) is a mechanism of treatment resistance in patients with advanced oncogene-driven lung adenocarcinoma (LUAD) that currently requires histologic review for diagnosis. Herein, we sought to develop an epigenomic cell-free DNA (cfDNA)-based approach to noninvasively detect small cell transformation in patients with EGFR mutant (EGFRm) LUAD.

EXPERIMENTAL DESIGN

To characterize the epigenomic landscape of transformed (t)SCLC relative to LUAD and de novo SCLC, we performed chromatin immunoprecipitation sequencing (ChIP-seq) to profile the histone modifications H3K27ac, H3K4me3, and H3K27me3; methylated DNA immunoprecipitation sequencing (MeDIP-seq); assay for transposase-accessible chromatin sequencing; and RNA sequencing on 26 lung cancer patient-derived xenograft (PDX) tumors. We then generated and analyzed H3K27ac ChIP-seq, MeDIP-seq, and whole genome sequencing cfDNA data from 1 mL aliquots of plasma from patients with EGFRm LUAD with or without tSCLC.

RESULTS

Analysis of 126 epigenomic libraries from the lung cancer PDXs revealed widespread epigenomic reprogramming between LUAD and tSCLC, with a large number of differential H3K27ac (n = 24,424), DNA methylation (n = 3,298), and chromatin accessibility (n = 16,352) sites between the two histologies. Tumor-informed analysis of each of these three epigenomic features in cfDNA resulted in accurate noninvasive discrimination between patients with EGFRm LUAD versus tSCLC [area under the receiver operating characteristic curve (AUROC) = 0.82-0.87]. A multianalyte cfDNA-based classifier integrating these three epigenomic features discriminated between EGFRm LUAD versus tSCLC with an AUROC of 0.94.

CONCLUSIONS

These data demonstrate the feasibility of detecting small cell transformation in patients with EGFRm LUAD through epigenomic cfDNA profiling of 1 mL of patient plasma.

Capmatinib plus nazartinib in patients with EGFR-mutated non-small cell lung cancer

PURPOSE

This phase 1b/2 trial evaluated the efficacy and safety of capmatinib plus nazartinib in patients with advanced EGFR-mutated non-small cell lung cancer (NSCLC).

METHODS

In phase 1b, patients with progression on first-/second-generation EGFR-TKIs received escalating doses of capmatinib 200-400 mg bid plus nazartinib 50-150 mg qd. Once the MTD/RP2D was declared, phase 2 commenced with patient enrollment into groups according to mutation status and prior lines of treatment: group 1 (fasted; EGFR-TKI resistant; 1-3 prior lines; EGFRL858R/ex19del; any T790M/MET); group 2 (fasted; EGFR-TKI naïve; 0-2 prior lines; de novo T790M+; any MET); group 3 (fasted; treatment-naïve; EGFRL858R/ex19del; T790M-; any MET); group 4 (with food; 0-2 prior lines; EGFRL858R/ex19del; any T790M/MET). Primary endpoints in phase 2 were investigator-assessed overall response rate (ORR) per RECIST v1.1 (groups 1-3), safety, and tolerability of the combination with food (group 4). Efficacy was assessed by T790M and MET status for a subgroup of patients.

RESULTS

The RP2D was capmatinib 400 mg bid plus nazartinib 100 mg qd. In phase 2 (n = 144), the ORR was 28.8 %, 33.3 %, 61.7 %, and 42.9 % in groups 1 (n = 52), 2 (n = 3), 3 (n = 47), and 4 (n = 42), respectively. In group 1 +phase 1b RP2D, the ORR was 45.8 %, 26.2 %, 37.9 %, and 32.4 % in MET+ (n = 24), MET- (n = 42), T790M+ (n = 29), and T790M- (n = 34) patients. Most common any-grade treatment-related adverse events (≥25 %; n = 144) were peripheral edema (54.9 %), nausea (41.7 %), diarrhea (34.0 %), and maculopapular rash (25.0 %).

CONCLUSION

Capmatinib plus nazartinib showed antitumor activity in patients with EGFR-TKI-resistant, EGFR-mutated NSCLC. The overall safety profile was acceptable.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov NCT02335944.

Anti-HDGF Antibody Targets EGFR Tyrosine Kinase Inhibitor-Tolerant Cells in NSCLC Patient-Derived Xenografts

Constitutively active mutant EGFR is one of the major oncogenic drivers in non-small cell lung cancer (NSCLC). Targeted therapy using EGFR tyrosine kinase inhibitor (TKI) is a first-line option in patients that have metastatic or recurring disease. However, despite the high response rate to TKI, most patients have a partial response, and the disease eventually progresses in 10 to 19 months. It is believed that drug-tolerant cells that survive TKI exposure during the progression-free period facilitate the emergence of acquired resistance. Thus, targeting the drug-tolerant cells could improve the treatment of NSCLC with EGFR mutations. We demonstrated here that EGFR-mutant patient-derived xenograft tumors responded partially to osimertinib despite near-complete inhibition of EGFR activation. Signaling in AKT/mTOR and MAPK pathways could be reactivated shortly after initial inhibition. As a result, many tumor cells escaped drug killing and regained growth following about 35 days of continuous osimertinib dosing. However, when an antibody to hepatoma-derived growth factor (HDGF) was given concurrently with osimertinib, tumors showed complete or near-complete responses. There was significant prolongation of progression-free survival of tumor-bearing mice as well. IHC and Western blot analysis of tumors collected in the early stages of treatment suggest that increased suppression of the AKT/mTOR and MAPK pathways could be a mechanism that results in enhanced efficacy of osimertinib when it is combined with an anti-HDGF antibody.

SIGNIFICANCE

These results suggest that HDGF could be critically involved in promoting tolerance to TKI in patient-derived xenografts of NSCLC tumors. Blocking HDGF signaling could be a potential means to enhance EGFR-targeted therapy of NSCLC that warrants further advanced preclinical and clinical studies.

Resistance mechanisms of EGFR tyrosine kinase inhibitors, in EGFR exon 20 insertion-mutant lung cancer

BACKGROUND

Mobocertinib, an EGFR exon 20 insertion (Ex20ins)-specific tyrosine kinase inhibitor has been used for treatment of advanced/metastatic EGFR Ex20ins-mutant non-small cell lung cancer (NSCLC). However, resistance mechanisms to EGFR Ex20ins-specific inhibitors and the efficacy of subsequent amivantamab treatment is unknown.

METHODS

To investigate resistance mechanisms, tissue and cfDNA samples were collected before treatment initiation and upon development of resistance from NSCLC patients with EGFR Ex20ins mutations received mobocertinib, poziotinib, and amivantamab treatments. Genetic alterations were analyzed using whole-genome and targeted sequencing, and in vitro resistant cell lines were generated for validation.

RESULTS

EGFR amplification (n = 6, including 2 broad copy number gain) and EGFR secondary mutation (n = 3) were observed at the resistance of mobocertinib. One patient had both EGFR secondary mutation and high EGFR focal amplification. In vitro models harboring EGFR alterations were constructed to validate resistance mechanisms and identify overcoming strategies to resistance. Acquired EGFR-dependent alterations were found to mediate resistance to mobocertinib in patients and in vitro models. Furthermore, two of six patients who received sequential amivantamab followed by an EGFR tyrosine kinase inhibitor had MET amplification and showed partial response.

CONCLUSIONS

Our study revealed EGFR-dependent and -independent mechanisms of mobocertinib resistance in patients with advanced EGFR Ex20ins-mutant NSCLC.

Mechanisms of resistance to tyrosine kinase inhibitor-targeted therapy and overcoming strategies

Tyrosine kinase inhibitor (TKI)-targeted therapy has revolutionized cancer treatment by selectively blocking specific signaling pathways crucial for tumor growth, offering improved outcomes with fewer side effects compared with conventional chemotherapy. However, despite their initial effectiveness, resistance to TKIs remains a significant challenge in clinical practice. Understanding the mechanisms underlying TKI resistance is paramount for improving patient outcomes and developing more effective treatment strategies. In this review, we explored various mechanisms contributing to TKI resistance, including on-target mechanisms and off-target mechanisms, as well as changes in the tumor histology and tumor microenvironment (intrinsic mechanisms). Additionally, we summarized current therapeutic approaches aiming at circumventing TKI resistance, including the development of next-generation TKIs and combination therapies. We also discussed emerging strategies such as the use of dual-targeted antibodies and PROteolysis Targeting Chimeras. Furthermore, we explored future directions in TKI-targeted therapy, including the methods for detecting and monitoring drug resistance during treatment, identification of novel targets, exploration of dual-acting kinase inhibitors, application of nanotechnologies in targeted therapy, and so on. Overall, this review provides a comprehensive overview of the challenges and opportunities in TKI-targeted therapy, aiming to advance our understanding of resistance mechanisms and guide the development of more effective therapeutic approaches in cancer treatment.

PrPC controls epithelial-to-mesenchymal transition in EGFR-mutated NSCLC: implications for TKI resistance and patient follow-up

Patients with EGFR-mutated non-small cell lung cancer (NSCLC) benefit from treatment with tyrosine kinase inhibitors (TKI) targeting EGFR. Despite improvements in patient care, especially with the 3rd generation TKI osimertinib, disease relapse is observed in all patients. Among the various processes involved in TKI resistance, epithelial-to-mesenchymal transition (EMT) is far from being fully characterized. We hypothesized that the cellular prion protein PrPC could be involved in EMT and EGFR-TKI resistance in NSCLC. Using 5 independent lung adenocarcinoma datasets, including our own cohort, we document that the expression of the PRNP gene encoding PrPC is associated with EMT. By manipulating the levels of PrPC in different EGFR-mutated NSCLC cell lines, we firmly establish that the expression of PrPC is mandatory for cells to maintain or acquire a mesenchymal phenotype. Mechanistically, we show that PrPC operates through an ILK-RBPJ cascade, which also controls the expression of EGFR. Our data further demonstrate that PrPC levels are elevated in EGFR-mutated versus wild-type tumours or upon EGFR activation in vitro. In addition, we provide evidence that PRNP levels increase with TKI resistance and that reducing PRNP expression sensitizes cells to osimertinib. Finally, we found that plasma PrPC levels are increased in EGFR-mutated NSCLC patients from 2 independent cohorts and that their longitudinal evolution mirrors that of disease. Altogether, these findings define PrPC as a candidate driver of EMT-dependent resistance to EGFR-TKI in NSCLC. They further suggest that monitoring plasma PrPC levels may represent a valuable non-invasive strategy for patient follow-up and warrant considering PrPC-targeted therapies for EGFR-mutated NSCLC patients with TKI failure.

Combination of Cytologic Findings and Circulating Tumor DNA From Cerebrospinal Fluid Revealed SCLC Transformation in Patients With Leptomeningeal Metastases of Lung Adenocarcinoma

Introduction

Transformation to SCLC is a resistance mechanism to tyrosine kinase inhibitor in EGFR-mutated lung adenocarcinoma (LUAD). Nevertheless, the clinical and molecular features of SCLC transformation in LUAD with leptomeningeal metastases (LM) are scarce.

Methods

We retrospectively collected 237 patients with NSCLC who underwent lumbar puncture owing to suggestion of LM. All SCLC transformation in cerebrospinal fluid (CSF) was confirmed by two experienced pathologists using cytologic evaluation. CSF circulating tumor DNA (ctDNA) was tested by next-generation sequencing.

Results

Tumor cells in CSF samples were found in 111 patients (111 of 237, 46.8%), and eight cases (eight of 111, 7.2%) were identified as having SCLC cells in CSF. Seven patients carried the EGFR mutation, including four patients with EGFR exon 19 deletion and three patients with EGFR exon 21 L858R mutation. Another patient harbored ERBB2 insertion. Seven of these patients were resistant to targeted therapy. CSF ctDNA analysis reported that TP53 and RB1 mutations were common. The median time from the diagnosis of advanced NSCLC to SCLC transformation found in CSF was 9.7 months (95% confidence interval [CI]: 4.0-17.5 mo). The median overall survival since the initial diagnosis of metastatic NSCLC was 15.3 months (95% CI: 1.2-29.4 mo). The median overall survival after SCLC transformation detected in CSF was 5.0 months (95% CI: 4.0-5.9 mo).

Conclusions

SCLC transformation may be revealed in CSF by both cytologic evaluation and ctDNA, not just in tissue that underwent rebiopsy. SCLC transformation of CSF is informative for resistance mechanism in patients with LUAD with LM on tyrosine kinase inhibitor progression, which was associated with poor survival.

Targeting therapy-persistent residual disease

Disease relapse driven by acquired drug resistance limits the effectiveness of most systemic anti-cancer agents. Targeting persistent cancer cells in residual disease before relapse has emerged as a potential strategy for enhancing the efficacy and the durability of current therapies. However, barriers remain to implementing persister-directed approaches in the clinic. This Perspective discusses current preclinical and clinical complexities and outlines key steps toward the development of clinical strategies that target therapy-persistent residual disease.

Enhancing intracranial efficacy prediction of osimertinib in non-small cell lung cancer: a novel approach through brain MRI radiomics

Introduction

Osimertinib, a third-generation EGFR-TKI, is known for its high efficacy against brain metastases (BM) in non-small cell lung cancer (NSCLC) due to its ability to penetrate the blood-brain barrier. This study aims to evaluate the use of brain MRI radiomics in predicting the intracranial efficacy to osimertinib in NSCLC patients with BM.

Materials and methods

This study analyzed 115 brain metastases from NSCLC patients with the EGFR-T790M mutation treated with second-line osimertinib. The primary endpoint was intracranial response, and the secondary endpoint was intracranial progression-free survival (iPFS). We performed tumor delineation, image preprocessing, and radiomics feature extraction. Using a 5-fold cross-validation strategy, we built radiomic models with eight feature selectors and eight machine learning classifiers. The models' performance was evaluated by the area under the receiver operating characteristic curve (AUC), calibration curves, and decision curve analysis.

Results

The dataset of 115 brain metastases was divided into training and validation sets in a 7:3 ratio. The radiomic model utilizing the mRMR feature selector and stepwise logistic regression classifier showed the highest predictive accuracy, with AUCs of 0.879 for the training cohort and 0.786 for the validation cohort. This model outperformed a clinical-MRI morphological model, which included age, ring enhancement, and peritumoral edema (AUC: 0.794 for the training cohort and 0.697 for the validation cohort). The radiomic model also showed strong performance in calibration and decision curve analyses. Using a radiomic-score threshold of 199, patients were classified into two groups with significantly different median iPFS (3.0 months vs. 15.4 months, p < 0.001).

Conclusion

This study demonstrates that MRI radiomics can effectively predict the intracranial efficacy of osimertinib in NSCLC patients with brain metastases. This approach holds promise for assisting clinicians in personalizing treatment strategies.

Immune status and combined immunotherapy progression in Kirsten rat sarcoma viral oncogene homolog (KRAS)-mutant tumors

Kirsten rat sarcoma viral oncogene homolog (KRAS) is the most frequently mutated oncogene, occurring in various tumor types. Despite extensive efforts over the past 40 years to develop inhibitors targeting KRAS mutations, resistance to these inhibitors has eventually emerged. A more precise understanding of KRAS mutations and the mechanism of resistance development is essential for creating novel inhibitors that target specifically KRAS mutations and can delay or overcome resistance. Immunotherapy has developed rapidly in recent years, and in-depth dissection of the tumor immune microenvironment has led researchers to shift their focus to patients with KRAS mutations, finding that immune factors play an essential role in KRAS-mutant (KRAS-Mut) tumor therapy and targeted drug resistance. Breakthroughs and transitions from targeted therapy to immunotherapy have provided new hope for treating refractory patients. Here, we reviewed KRAS mutation-targeted treatment strategies and resistance issues, focusing on our in-depth exploration of the specific immune status of patients with KRAS mutations and the impact of body immunity following KRAS inhibition. We aimed to guide innovative approaches combining RAS inhibition with immunotherapy, review advances in preclinical and clinical stages, and discuss challenges and future directions.

Inhibition of ULK1/2 and KRASG12C controls tumor growth in preclinical models of lung cancer

Mutational activation of KRAS occurs commonly in lung carcinogenesis and, with the recent U.S. Food and Drug Administration approval of covalent inhibitors of KRASG12C such as sotorasib or adagrasib, KRAS oncoproteins are important pharmacological targets in non-small cell lung cancer (NSCLC). However, not all KRASG12C-driven NSCLCs respond to these inhibitors, and the emergence of drug resistance in those patients who do respond can be rapid and pleiotropic. Hence, based on a backbone of covalent inhibition of KRASG12C, efforts are underway to develop effective combination therapies. Here, we report that the inhibition of KRASG12C signaling increases autophagy in KRASG12C-expressing lung cancer cells. Moreover, the combination of DCC-3116, a selective ULK1/2 inhibitor, plus sotorasib displays cooperative/synergistic suppression of human KRASG12C-driven lung cancer cell proliferation in vitro and superior tumor control in vivo. Additionally, in genetically engineered mouse models of KRASG12C-driven NSCLC, inhibition of either KRASG12C or ULK1/2 decreases tumor burden and increases mouse survival. Consequently, these data suggest that ULK1/2-mediated autophagy is a pharmacologically actionable cytoprotective stress response to inhibition of KRASG12C in lung cancer.

Impact of Neuroendocrine Differentiation (NED) on Enzalutamide and Abiraterone Efficacy in Metastatic Castration-Resistant Prostate Cancer (mCRPC): A Retrospective Analysis

Neuroendocrine differentiation (NED) represents a possible androgen receptor pathway inhibitors (ARPI) resistance mechanism in metastatic castration resistance prostate cancer (mCRPC). As mCRPC with NED has been excluded from clinical trials evaluating ARPI efficacy, this study investigates the prognostic impact of NED in mCRPC patients treated with ARPIs. Methods: We retrospectively analyzed 327 mCRPC patient data treated with Enzalutamide or Abiraterone in the first and second or successive lines of treatment. NED was assessed using prostate biopsy samples through immunohistochemical staining. Results: NED was confirmed in 32/327 (9.8%) mCRPC patients. In the overall population, mCRPC with NED showed worse PFS (4.38 vs. 11.48 months HR 2.505 [1.71-3.68] p < 0.05), disease control rate (DCR), and PSA response. In the first line setting, mCRPC with NED demonstrated worse PFS (8.5 vs. 14.9 months HR 2.13 [1.18-3.88], p < 0.05). Similarly, in the second or successive lines, mCRPC with NED showed worse PFS (4.0 vs. 7.5 months HR 2.43 [1.45-4.05] p < 0.05), DCR, PSA response and OS (12.53 vs. 18.03 months HR 1.86 [1.12-3.10] p < 0.05). The adverse impact of NED on PFS was consistence across all subgroups; we also noted a trend of worse PFS in patients with high vs. low NED. Conclusions: In our study, mCRPC with NED treated with Enzalutamide or Abiraterone showed worse clinical outcomes. NED assessment should be considered to optimize treatment decisions in the mCRPC setting.

Potential therapeutic option for EGFR-mutant small cell lung cancer transformation: a case report and literature review

Transformation from non-small cell lung cancer (NSCLC) to small cell lung cancer (SCLC) is rare and is associated with poor prognosis. However, the standard treatment protocols for patients with SCLC transformation remain unknown. Here, we report the case of a patient with advanced EGFR exon 19 deletion (19del) NSCLC who underwent SCLC transformation during targeted therapy. Biopsies and genetic testing were performed to adjust treatment regimens accordingly. The patient responded favorably to a combined treatment regimen comprising etoposide plus cisplatin chemotherapy and adebrelimab plus osimertinib. This case highlights the critical importance of acknowledging tumor heterogeneity in clinical decision-making and identifying potentially effective treatment options for patients with SCLC transformation. Additionally, we reviewed cases of the transformation of NSCLC to SCLC from 2017 to 2023.

An identity crisis for lung cancer cells

Omic analysis of clinical specimens undergoing histological transformation defines targetable drivers to prevent plasticity and treatment resistance.

Gefitinib (an EGFR tyrosine kinase inhibitor) plus anlotinib (an multikinase inhibitor) for untreated, EGFR-mutated, advanced non-small cell lung cancer (FL-ALTER): a multicenter phase III trial

Dual inhibition of vascular endothelial growth factor and epidermal growth factor receptor (EGFR) signaling pathways offers the prospect of improving the effectiveness of EFGR-targeted therapy. In this phase 3 study (ClinicalTrial.gov: NCT04028778), 315 patients with treatment-naïve, EGFR-mutated, advanced non-small cell lung cancer (NSCLC) were randomized (1:1) to receive anlotinib or placebo plus gefitinib once daily on days 1-14 per a 3-week cycle. At the prespecified final analysis of progression-free survival (PFS), a significant improvement in PFS was observed for the anlotinib arm over the placebo arm (hazards ratio [HR] = 0.64, 95% CI, 0.48-0.80, P = 0.003). Particularly, patients with brain metastasis and those harboring EGFR amplification or high tumor mutation load gained significant more benefits in PFS from gefitinib plus anlotinib. The incidence of grade 3 or higher treatment-emergent adverse events was 49.7% of the patients receiving gefitinib plus anlotinib versus 31.0% of the patients receiving gefitinib plus placebo. Anlotinib plus gefitinib significantly improves PFS in patients with treatment-naïve, EGFR-mutated, advanced NSCLC, with a manageable safety profile.

ZNF397 Deficiency Triggers TET2-Driven Lineage Plasticity and AR-Targeted Therapy Resistance in Prostate Cancer

Cancer cells exhibit phenotypical plasticity and epigenetic reprogramming that allows them to evade lineage-dependent targeted treatments by adopting lineage plasticity. The underlying mechanisms by which cancer cells exploit the epigenetic regulatory machinery to acquire lineage plasticity and therapy resistance remain poorly understood. We identified zinc finger protein 397 (ZNF397) as a bona fide coactivator of the androgen receptor (AR), essential for the transcriptional program governing AR-driven luminal lineage. ZNF397 deficiency facilitates the transition of cancer cell from an AR-driven luminal lineage to a ten-eleven translocation 2 (TET2)-driven lineage plastic state, ultimately promoting resistance to therapies inhibiting AR signaling. Intriguingly, our findings indicate that a TET2 inhibitor can eliminate the resistance to AR-targeted therapies in ZNF397-deficient tumors. These insights uncover a novel mechanism through which prostate cancer acquires lineage plasticity via epigenetic rewiring and offer promising implications for clinical interventions designed to overcome therapy resistance dictated by lineage plasticity. Significance: This study reveals a bifurcated role of ZNF397, and a TET2-driven epigenetic mechanism regulating tumor lineage plasticity and therapy response in prostate cancer, enhances the understanding of drug resistance, and unveils a new therapeutic strategy for overcoming androgen receptor-targeted therapy resistance.

Emerging advances in defining the molecular and therapeutic landscape of small-cell lung cancer

Small-cell lung cancer (SCLC) has traditionally been considered a recalcitrant cancer with a dismal prognosis, with only modest advances in therapeutic strategies over the past several decades. Comprehensive genomic assessments of SCLC have revealed that most of these tumours harbour deletions of the tumour-suppressor genes TP53 and RB1 but, in contrast to non-small-cell lung cancer, have failed to identify targetable alterations. The expression status of four transcription factors with key roles in SCLC pathogenesis defines distinct molecular subtypes of the disease, potentially enabling specific therapeutic approaches. Overexpression and amplification of MYC paralogues also affect the biology and therapeutic vulnerabilities of SCLC. Several other attractive targets have emerged in the past few years, including inhibitors of DNA-damage-response pathways, epigenetic modifiers, antibody-drug conjugates and chimeric antigen receptor T cells. However, the rapid development of therapeutic resistance and lack of biomarkers for effective selection of patients with SCLC are ongoing challenges. Emerging single-cell RNA sequencing data are providing insights into the plasticity and intratumoural and intertumoural heterogeneity of SCLC that might be associated with therapeutic resistance. In this Review, we provide a comprehensive overview of the latest advances in genomic and transcriptomic characterization of SCLC with a particular focus on opportunities for translation into new therapeutic approaches to improve patient outcomes.

Real-world applications of the new grading system in lung adenocarcinoma: A study of 907 patients focusing on revealing the relationship between pathologic grade and genetic status

BACKGROUND

The status of the lung adenocarcinoma (LUAD) grading system and the association between LUAD differentiation, driver genes, and clinicopathological features remain to be elucidated.

METHODS

We included patients with invasive non-mucinous LUAD, evaluated their differentiation, and collected available clinicopathological information, gene mutations, and analyzed clinical outcomes.

RESULTS

Among the 907 patients with invasive non-mucinous LUAD, 321 (35.4 %) were poorly differentiated, 422 (46.5 %) were moderately differentiated, and 164 (18.1 %) were well differentiated. EGFR mutation was more common in the LUADs accompanied without CGP (complex glandular pattern) than LUADs with CGP (p < 0.001). Correlation analysis between mutations and clinical characteristics showed that EGFR gene mutation (p < 0.001), KRAS gene mutation (p < 0.05), and ALK gene rearrangement (p < 0.001) were significantly related to the degree of tumor differentiation, and the KRAS and ALK gene mutation frequencies were higher in the low-differentiation group than in the high and medium differentiation groups. The EGFR mutation frequency was higher in the well/moderately differentiated adenocarcinoma group.

CONCLUSIONS

Our study adds to the evidence regarding the role of the grading system in prognosis. EGFR, KRAS, and ALK are related to the degree of tumor differentiation.

PD-L1 expression from surgically resected lung tumors predictive of early progression in patients previously treated with targeted therapy for initially unresectable non-small cell lung cancer

Background

Recent evidences showed that resection of lung tumor post-targeted therapy has shown progression-free survival (PFS) benefits in initially unresectable patients. The aim of this study is to evaluate pathologic findings of resected lung tumor samples in patients who have undergone prior epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitor (TKI) treatment, and also to assess the prognostic factors related to outcomes after resection.

Methods

The deidentified data of non-small cell lung cancer (NSCLC) patients admitted to seven university hospitals affiliated with the Catholic University of Korea were obtained from the Clinical Data Warehouse (CDW) database. Among screened patients, 40 individuals who had previously undergone targeted therapies and later received surgical resection of a primary lung tumor were evaluated for the study.

Results

All 40 patients were diagnosed with adenocarcinoma. Of these, 36 with EGFR mutations received prior EGFR TKI treatment. Only one postoperative complication, atrial fibrillation, was observed. At the time of resection, 19 patients showed primary lung tumor size regressing or unchanged, while 21 patients showed primary lung tumor regrowth or new lesions being developed before the resection. The group with no programmed death-ligand 1 (PD-L1) expression from resected samples showed significantly better post-resection PFS when compared to the other group (P=0.01). In the Model II multivariate analysis for post-resection PFS, PD-L1 detection from the resected sample was significantly associated with PFS [P=0.03; hazard ratio (HR) =5.465; 95% confidence interval (CI): 1.200-24.885]. Furthermore, an increase in PD-L1 expression compared to the baseline value was associated with an increasing lung tumor burden at the time of resection (P=0.03).

Conclusions

Resected specimen following targeted therapy can provide valuable clinical information that can be used to predict the prognosis of patients with initially unresectable NSCLC.

CCL2 promotes EGFR-TKIs resistance in non-small cell lung cancer via the AKT-EMT pathway

Acquired resistance to EGFR tyrosine kinase inhibitors (EGFR-TKIs) represents a primary cause of treatment failure in non-small cell lung cancer (NSCLC) patients. Chemokine (C-C motif) ligand 2 (CCL2) is recently found to play a pivotal role in determining anti-cancer treatment response. However, the role and mechanism of CCL2 in the development of EGFR-TKIs resistance have not been fully elucidated. In the present study, we focus on the function of CCL2 in the development of acquired resistance to EGFR-TKIs in NSCLC cells. Our results show that CCL2 is aberrantly upregulated in EGFR-TKIs-resistant NSCLC cells and that CCL2 overexpression significantly diminishes sensitivity to EGFR-TKIs. Conversely, CCL2 suppression by CCL2 synthesis inhibitor, bindarit, or CCL2 knockdown can reverse this resistance. CCL2 upregulation can also lead to enhanced migration and increased expressions of epithelial-mesenchymal transition (EMT) markers in EGFR-TKI-resistant NSCLC cells, which could also be rescued by CCL2 knockdown or inhibition. Furthermore, our findings suggest that CCL2-dependent EGFR-TKIs resistance involves the AKT-EMT signaling pathway; inhibition of this pathway effectively attenuates CCL2-induced cell migration and EMT marker expression. In summary, CCL2 promotes the development of acquired EGFR-TKIs resistance and EMT while activating AKT signaling in NSCLC. These insights suggest a promising avenue for the development of CCL2-targeted therapies that prevent EGFR-TKIs resistance in NSCLC.

Circulating Tumor DNA-Guided De-Escalation Targeted Therapy for Advanced Non-Small Cell Lung Cancer: A Nonrandomized Controlled Trial

Importance

Uninterrupted targeted therapy until disease progression or intolerable toxic effects is currently the routine therapy for advanced non-small cell lung cancer (NSCLC) involving driver gene variations. However, drug resistance is inevitable.

Objective

To assess the clinical feasibility of adaptive de-escalation tyrosine kinase inhibitor (TKI) treatment guided by circulating tumor DNA (ctDNA) for achieving complete remission after local consolidative therapy (LCT) in patients with advanced NSCLC.

Design, Setting, and Participants

This prospective nonrandomized controlled trial was conducted at a single center from June 3, 2020, to July 19, 2022, and included 60 patients with advanced NSCLC with driver variations without radiologically detectable disease after TKI and LCT. The median (range) follow-up time was 19.2 (3.8-29.7) months. Data analysis was conducted from December 15, 2022, to May 10, 2023.

Intervention

Cessation of TKI treatment and follow-up every 3 months. Treatment was restarted in patients with progressive disease (defined by the Response Evaluation Criteria in Solid Tumors 1.1 criteria), detectable ctDNA, or elevated carcinoembryonic antigen (CEA) levels, whichever manifested first, and treatment ceased if all indicators were negative during follow-up surveillance.

Main Outcomes and Measures

Progression-free survival (PFS). Secondary end points were objective response rate, time to next treatment, and overall survival.

Results

Among the total study sample of 60 participants (median [range] age, 55 [21-75] years; 33 [55%] were female), the median PFS was 18.4 (95% CI, 12.6-24.2) months and the median (range) total treatment break duration was 9.1 (1.5-28.1) months. Fourteen patients (group A) remained in TKI cessation with a median (range) treatment break duration of 20.3 (6.8-28.1) months; 31 patients (group B) received retreatment owing to detectable ctDNA and/or CEA and had a median PFS of 20.2 (95% CI, 12.9-27.4) months with a median (range) total treatment break duration of 8.8 (1.5-20.6) months; and 15 patients (group C) who underwent retreatment with TKIs due to progressive disease had a median PFS of 5.5 (95% CI, 1.5-7.2) months. For all participants, the TKI retreatment response rate was 96%, the median time to next treatment was 29.3 (95% CI, 25.3-35.2) months, and the data for overall survival were immature.

Conclusions and Relevance

The findings of this nonrandomized controlled trial suggest that this adaptive de-escalation TKI strategy for patients with NSCLC is feasible in those with no lesions after LCT and a negative ctDNA test result. This might provide a de-escalation treatment strategy guided by ctDNA for the subset of patients with advanced NSCLC.

Trial Registration

ClinicalTrials.gov Identifier: NCT03046316.

Metal complexes bearing EGFR-inhibiting ligands as promising anticancer agents

Overexpression of the epidermal growth factor receptor (EGFR, erbB1) has been observed in a wide range of solid tumors and has frequently been associated with poor prognosis. As a result, EGFR inhibition has become an attractive anticancer drug design strategy, and a large number of small molecular inhibitors have been developed. Despite the widespread clinical use of EGFR tyrosine kinase inhibitors (TKIs), their drug resistance, inadequate accumulation in tumors, and severe side effects have spurred the search for better antitumor drugs. Metal complexes have attracted much attention because of their different mechanisms compared with EGFR-TKIs. Therefore, the combination of metals and inhibitors is a promising anticancer strategy. For example, Ru and Pt centers are introduced to design complexes with double or multiple targets, while Au complexes are combined with inhibitors to overcome drug resistance. Co complexes are designed as prodrugs with weak side effects and enhanced targeting by the hypoxia activation strategy, and other metals such as Rh and Fe enhance the anticancer effect of the complexes. In addition, the introduction of Ga center is beneficial to the development of nuclear imaging tracers. In this paper, metal EGFR-TKI complexes in the last 15 years are reviewed, their mechanisms are briefly introduced, and their advantages are summarized.

Histologic transformation of non-small-cell lung cancer in response to tyrosine kinase inhibitors: Current knowledge of genetic changes and molecular mechanisms

Lung cancer is the leading cause of cancer death and includes two major types: non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC), accounting for 85% and 15% of cases, respectively. Non-small-cell lung cancer harboring actionable driver mutations is generally treated with tyrosine kinase inhibitors (TKIs) molecularly targeting individual oncogenes. Although TKIs have greatly contributed to better clinical outcomes, acquired resistance to them inevitably occurs. Histologic or lineage transformation is a rare but well-documented off-target mechanism associated with acquired resistance, and has been identified in settings following treatment with multiple different TKIs and other drugs. It includes neuroendocrine transformation, squamous cell transformation, and epithelial-to-mesenchymal transition. Here, we review the clinicopathologic features of transformed tumors and current understanding of the key genetic alterations and biologic mechanism of lineage transformation in NSCLC, particularly TKI-triggered transformation.

Farnesyltransferase inhibition overcomes oncogene-addicted non-small cell lung cancer adaptive resistance to targeted therapies

Drug-tolerance has emerged as one of the major non-genetic adaptive processes driving resistance to targeted therapy (TT) in non-small cell lung cancer (NSCLC). However, the kinetics and sequence of molecular events governing this adaptive response remain poorly understood. Here, we combine real-time monitoring of the cell-cycle dynamics and single-cell RNA sequencing in a broad panel of oncogenic addiction such as EGFR-, ALK-, BRAF- and KRAS-mutant NSCLC, treated with their corresponding TT. We identify a common path of drug adaptation, which invariably involves alveolar type 1 (AT1) differentiation and Rho-associated protein kinase (ROCK)-mediated cytoskeletal remodeling. We also isolate and characterize a rare population of early escapers, which represent the earliest resistance-initiating cells that emerge in the first hours of treatment from the AT1-like population. A phenotypic drug screen identify farnesyltransferase inhibitors (FTI) such as tipifarnib as the most effective drugs in preventing relapse to TT in vitro and in vivo in several models of oncogenic addiction, which is confirmed by genetic depletion of the farnesyltransferase. These findings pave the way for the development of treatments combining TT and FTI to effectively prevent tumor relapse in oncogene-addicted NSCLC patients.

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

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

CRACD loss induces neuroendocrine cell plasticity of lung adenocarcinoma

Tumor cell plasticity contributes to intratumoral heterogeneity and therapy resistance. Through cell plasticity, some lung adenocarcinoma (LUAD) cells transform into neuroendocrine (NE) tumor cells. However, the mechanisms of NE cell plasticity remain unclear. CRACD (capping protein inhibiting regulator of actin dynamics), a capping protein inhibitor, is frequently inactivated in cancers. CRACD knockout (KO) is sufficient to de-repress NE-related gene expression in the pulmonary epithelium and LUAD cells. In LUAD mouse models, Cracd KO increases intratumoral heterogeneity with NE gene expression. Single-cell transcriptomic analysis showed that Cracd KO-induced NE cell plasticity is associated with cell de-differentiation and stemness-related pathway activation. The single-cell transcriptomic analysis of LUAD patient tumors recapitulates that the distinct LUAD NE cell cluster expressing NE genes is co-enriched with impaired actin remodeling. This study reveals the crucial role of CRACD in restricting NE cell plasticity that induces cell de-differentiation of LUAD.

Potential Utility of a 4th-Generation EGFR-TKI and Exploration of Resistance Mechanisms-An In Vitro Study

The emergence of acquired resistance to EGFR-tyrosine kinase inhibitors (TKIs) is almost inevitable even after a remarkable clinical response. Secondary mutations such as T790M and C797S are responsible for the resistance to 1st/2nd-generation (1/2G) TKIs and 3G TKIs, respectively. To overcome both the T790M and C797S mutations, novel 4G EGFR-TKIs are now under early clinical development. In this study, we evaluated the efficacy of a 4G EGFR-TKI in the treatment of lung cancer with EGFR mutation as well as explored resistance mechanisms to a 4G TKI. First, we compared the efficacies of seven TKIs including a 4G TKI, BI4020, against Ba/F3 cell models that simulate resistant tumors after front-line osimertinib treatment failure because of a secondary mutation. We also established acquired resistant cells to BI4020 by chronic drug exposure. Ba/F3 cells with an osimertinib-resistant secondary mutation were refractory to all 3G TKIs tested (alflutinib, lazertinib, rezivertinib, almonertinib, and befotertinib). BI4020 inhibited the growth of C797S-positive cells; however, it was not effective against L718Q-positive cells. Erlotinib was active against all Ba/F3 cells tested. In the analysis of resistance mechanisms of BI4020-resistant (BIR) cells, none harbored secondary EGFR mutations. HCC827BIR cells had MET gene amplification and were sensitive to a combination of capmatinib (MET-TKI) and BI4020. HCC4006BIR and H1975BIR cells exhibited epithelial-to-mesenchymal transition. This study suggests that erlotinib may be more suitable than 4G TKIs to overcome secondary mutations after front-line osimertinib. We found that off-target mechanisms that cause resistance to earlier-generation TKIs will also cause resistance to 4G TKIs.

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).

Transformation of epidermal growth factor receptor mutated lung adenocarcinoma to small-cell carcinoma long after the cessation of tyrosine kinase inhibitor treatment: A case series and literature review

Histological transformation to small-cell lung cancer (SCLC) is a well-known mechanism of acquired resistance to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs), and almost all patients receive EGFR-TKIs at the time of transformation. We herein report three cases of EGFR-mutated lung adenocarcinoma that transformed into SCLC long after the cessation of EGFR-TKIs. Rapid tumor progression and elevated SCLC marker levels were observed at the time of transformation. Our case highlights the importance of considering SCLC transformation throughout the clinical course. Careful observation of the tumor behavior and SCLC markers should be performed to avoid diagnostic delays.

Inhibition of ULK1/2 and KRAS G12C controls tumor growth in preclinical models of lung cancer

Mutational activation of KRAS occurs commonly in lung carcinogenesis and, with the recent FDA approval of covalent inhibitors of KRAS G12C such as sotorasib or adagrasib, KRAS oncoproteins are important pharmacological targets in non-small cell lung cancer (NSCLC). However, not all KRAS G12C -driven NSCLCs respond to these inhibitors, and the emergence of drug resistance in those patients that do respond can be rapid and pleiotropic. Hence, based on a backbone of covalent inhibition of KRAS G12C , efforts are underway to develop effective combination therapies. Here we report that inhibition of KRAS G12C signaling increases autophagy in KRAS G12C expressing lung cancer cells. Moreover, the combination of DCC-3116, a selective ULK1/2 inhibitor, plus sotorasib displays cooperative/synergistic suppression of human KRAS G12C -driven lung cancer cell proliferation in vitro and superior tumor control in vivo . Additionally, in genetically engineered mouse models of KRAS G12C -driven NSCLC, inhibition of either KRAS G12C or ULK1/2 decreases tumor burden and increases mouse survival. Consequently, these data suggest that ULK1/2-mediated autophagy is a pharmacologically actionable cytoprotective stress response to inhibition of KRAS G12C in lung cancer.