Search

BRAFV600E mutation confers a poor prognosis in metastatic colorectal cancer (CRC) despite combinatorial targeted therapies based on the latest understanding of signaling circuitry. To identify parallel resistance mechanisms induced by BRAF–MEK–EGFR co-targeting, we used a high-throughput kinase activity mapping platform. Here we show that SRC kinases are systematically activated in BRAFV600E CRC following targeted inhibition of BRAF ± EGFR and that coordinated targeting of SRC with BRAF ± EGFR increases treatment efficacy in vitro and in vivo. SRC drives resistance to BRAF ± EGFR targeted therapy independently of ERK signaling by inducing transcriptional reprogramming through β-catenin (CTNNB1). The EGFR-independent compensatory activation of SRC kinases is mediated by an autocrine prostaglandin E2 loop that can be blocked with cyclooxygenase-2 (COX2) inhibitors. Co-targeting of COX2 with BRAF + EGFR promotes durable suppression of tumor growth in patient-derived tumor xenograft models. COX2 inhibition represents a drug-repurposing strategy to overcome therapeutic resistance in BRAFV600E CRC.

International audience; INTRODUCTION: Molecular profile of resected stage I-II non-small cell lung cancer (NSCLC) would help refine prognosis and personalize induction or adjuvant strategies. We sought to report the molecular profile of resected stage I-II NSCLC and analyzed the impact of epidermal growth factor receptor (EGFR) mutations on outcomes in a Western population. PATIENTS AND METHODS: Surgical cases were identified from Biomarkers France study, a nationwide prospective study including NSCLC patients screened for EGFR, HER2, KRAS, BRAF, PIK3CA, ALK alterations from 2012 to 2013. Among surgical patients, clinical charts of the largest centers were reviewed in order to analyze the prognostic impact of EGFR mutations. RESULTS: In the BMF database (n = 17.636), surgical patients (n = 854) were characterized by a higher proportion of EGFR mutations than nonsurgical patients (12.9% vs. 10.2%, P = .025), while the other molecular alterations did not differ. The proportion of EGFR mutations was 27% in women undergoing surgery. In the study group (n = 293; EGFR wild type, n = 235; usual mutation, n = 50; rare mutation, n = 8), after a median follow-up of 67 months, 215 patients (74.4%) had not relapsed. No difference was found between EGFR-mutant and EGFR-wt tumors regarding recurrence site, disease-free survival, and overall survival. The 5-year disease-free survival and overall survival after surgical resection of stage I-II EGFR-mutated tumors were 65% and 75%, respectively. CONCLUSION: In resected stage I to II NSCLC, EGFR mutations were found in 12.9% of cases, associated with a 5-year overall survival of 75%, with no impact on recurrence site, disease-free survival, and overall survival.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. The randomized, open-label, phase II EVAN study investigated the efficacy (disease-free survival [DFS] and 5-year overall survival [OS]) and safety of erlotinib versus vinorelbine/cisplatin as adjuvant chemotherapy after complete resection (R0) for stage III epidermal growth factor receptor ( EGFR) mutation+ non–small-cell lung cancer. We describe the updated results at the 43-month follow-up. In EVAN, patients were randomly assigned (1:1) to erlotinib (n = 51) or vinorelbine/cisplatin (n = 51). The median follow-up was 54.8 and 63.9 months in the erlotinib and chemotherapy arms, respectively. With erlotinib, the respective 5-year DFS by Kaplan-Meier analysis was 48.2% (95% CI, 29.4 to 64.7) and 46.2% (95% CI, 27.6 to 62.9) in the intention-to-treat and per-protocol populations. The median OS was 84.2 months with erlotinib versus 61.1 months with chemotherapy (hazard ratio, 0.318; 95% CI, 0.151 to 0.670). The 5-year survival rates were 84.8% and 51.1% with erlotinib and chemotherapy, respectively. In whole-exome sequencing analysis, frequent genes with variants co-occurring at baseline were TP53, MUC16, FAM104B, KMT5A, and DNAH9. With erlotinib, a single-nucleotide polymorphism mutation in UBXN11 was associated with significantly worse DFS ( P = .01). To our knowledge, this study is the first to demonstrate clinically meaningful OS improvement with adjuvant erlotinib compared with chemotherapy in R0 stage III EGFR+ non–small-cell lung cancer.

e21076 Background: Results of IMpower-150 and Orient-31 have demonstrated a favorable effect of combining anti-angiogenic therapy and checkpoint inhibition for refractory NSCLC patients with EGFR mutations. However, both studies included only very few patients with uncommon EGFR mutations, not allowing further analysis. For those patients, representing about 10% of EGFR mutant NSCLCs, treatment options are still limited. Methods: Analysis included 16 stage IV NSCLC patients with uncommon EGFR mutations from 9 different German centers which started treatment in first or further line with Atezolizumab, Bevacizumab, Carboplatin and (nab-)Paclitaxel (ABCP) between October 2018 and January 2022. EGFR mutations were detected by NGS (n = 15) or COBAS-PCR (n = 1). PFS was evaluated from start of ABCP and OS from time of initial diagnosis of stage IV. Results: 5 men and 11 women received ABCP therapy in first (n = 4), second (n = 9) or further line (n = 3). Mean age was 56 (36-77) years. Patients had either an Exon 20 insertion (n = 9) or point mutation (n = 2, S768I), an Exon 18 mutation (n = 3, G719X or E709A), an Exon 21 mutation (L861Q) or a compound mutation (G719C/S768I). 9 patients received a TKI therapy in first line (4x Afatinib; 5x Osimertinib) with an ORR of 66.7% (CR = 1; PR = 5; SD = 1; PD = 2) and a median time-to-next-treatment of 6.7 months (range: 2.1-39.1 months). Median number of full ABCP cycles were 4 (1-6), with 3 patients (23.1%) requiring a dose reduction of chemotherapy and 4 patients (30.8%) suffering from grade 3 or 4 toxicity (one immune related pneumonitis). 13 patients (84.6%) received a maintenance with AB and the median follow-up after initial diagnosis was 19.6 months (2.3-38.4). ORR was 81.3% with 2 CR, 11 PR, 1 SD and 1 PD (not available = 1). Median PFS by Kaplan-Meier analysis was 13.0 months for both the entire cohort (95%-CI: 8.4-17.6) and for Exon 20 insertions (95%-CI: 9.3-16.7). Corresponding median OS was either not reached or 30.7 months (95%-CI: 13.8-47.6). Landmark analysis at 12 months gave a PFS of 42.8% and an OS of 93.3%. Univariate Cox regression showed no association of PFS or OS with patient or treatment parameters, including PD-L1 expression, type of mutation or prior TKI treatment. 4 patients were rechallenged with ABCP while progressing under AB maintenance and responded again. 4 patients received mobocertinib as further treatment, but only one showed a clinical benefit. Conclusions: In this retrospective analysis, ABCP achieves an encouraging outcome for patients with uncommon EGFR mutations, comparable to results for common EGFR mutations in IMpower150 (ORR 71%, mPFS: 9.7 months, mOS 29.4 months). This in contrast to immunotherapy alone which shows poor ORR and PFS. Together with new targeted treatment options for Exon 20 insertions like amivantamab (ORR 40%, mPFS 8.3 months) or mobocertinib (ORR 28%, mPFS 7.3 months), ABCP is a valuable option in the early course of treatment for this patient cohort.

Epidermal growth factor receptor (EGFR) exon 20 insertion mutations (ex20ins) account for ≤ 12% of all EGFR-mutant nonsmall cell lung cancers. We analysed real-world datasets to determine the frequency of ex20ins variants, and the ability of polymerase chain reaction (PCR) and next-generation sequencing (NGS) to identify them. Three real-world United States NGS databases were used: GENIE, FoundationInsights, and GuardantINFORM. Mutation profiles consistent with in-frame EGFR ex20ins were summarized. GENIE, FoundationInsights, and GuardantINFORM datasets identified 180, 627, and 627 patients with EGFR ex20ins respectively. The most frequent insertion region of exon 20 was the near loop (~ 70%), followed by the far loop (~ 30%) and the helical (~ 3-6%) regions. GENIE, FoundationInsights, and GuardantINFORM datasets identified 41, 102, and 96 unique variants respectively. An analysis of variants projected that ~ 50% of EGFR ex20ins identified by NGS would have been missed by PCR-based assays. Given the breadth of EGFR ex20ins identified in the real-world US datasets, the ability of PCR to identify these mutations is limited. NGS platforms are more appropriate to identify patients likely to benefit from EGFR ex20ins-targeted therapies.

The role of local consolidative therapy (LCT) for metastatic cancers most likely varies by the particular cancer type. We therefore performed a systematic review with a comparative meta-analysis of LCT versus systemic therapy alone, specifically for metastatic non-small cell lung cancer (mNSCLC).Article eligibility for this Preferred Reporting Items for Systematic Reviews and Meta-Analyses/Population, Intervention, Comparison, Outcomes and Design-guided systematic review was histologic confirmation of mNSCLC, comparison of LCT (irradiation/surgery) versus lack thereof in a randomized or propensity-matched retrospective manner, and sufficient quantitative data examining progression-free survival (PFS), overall survival (OS), and/or adverse events (AEs). Both polymetastatic and oligometastatic disease (OMD) were allowed, but not oligoprogressive/oligorecurrent disease. Statistics used the Mantel-Haenszel fixed-effect or random-effect model depending on the heterogeneity (IFrom 7 articles, 346 patients received LCT and 347 received systemic therapy alone. With LCT, the hazard ratio (HR) for PFS in all patients was 0.37 (95% confidence interval, 0.25-0.55; P = .01), and for OMD it was 0.30 (0.24-0.38; P.001). For OS, the HRs were 0.53 (0.45-0.62; P.001) in all patients, and 0.41 (0.33-0.52; P.001) in patients with OMD. The findings remained significant when stratifying by epidermal growth factor receptor status (HRs for PFS/OS: 0.29/0.44 for mutants and 0.31/0.39 for wild-type, respectively, P.001 for all) and study type (HRs for PFS/OS: 0.40/0.52 for randomized and 0.33/0.41 for retrospective, respectively, P.05 for all). LCT was not associated with a higher rate of grade ≥3 AEs (odds ratio, 1.28; 95% confidence interval, 0.81-2.05; P = .29).Meta-analyzing the available data shows that LCT may improve the PFS and OS of mNSCLC without increasing the risk of high-grade AEs. However, further data on polymetastatic mNSCLC are required, and these conclusions cannot be extrapolated to other (non-mNSCLC) histologies. Although many existing/ongoing trials of LCT for OMD commonly comprise mixed-histology populations, focusing on the interaction between specific tumor biology and systemic agents is required to enhance the clarity and applicability of these trials.

Hispanics living in the United States have higher rates of Epidermal Growth Factor Receptor (EGFR) mutations compared with Non-Hispanic Whites. While this higher incidence is like Asian patients living in the United States, the outcomes for Hispanic patients differ. We looked to compare the variances in mutational profiles between Hispanics and Asians in Los Angeles.Three hundred ninety three non-small cell lung cancer (NSCLC) patients treated at Los Angeles County + University of Southern California (LAC + USC) Medical Center and Norris Comprehensive Cancer Center who received comprehensive genomic profiling (CGP) were evaluated from July 2017 to August 2020. CGP was done using tissue biopsies (n = 211) from Caris Life Sciences and liquid biopsies (n = 231) from Guardant Health. Multivariate logistic regression evaluated the role of race between Hispanics and Asians.In the Hispanic cohort (n = 90), 50.0% were male, median age of diagnosis was 62, 54.5% were non-smokers, and 85.5% had adenocarcinoma. In Asians (n = 142), 47.5% were male, median age of diagnosis was 65, 59.6% were non-smokers, and 83.8% had adenocarcinoma. Hispanic patients had greater prevalence of Kirsten rat sarcoma virus (KRAS) mutations (odds ratio [OR] 4.42, 95% confidence interval [95% CI]: 1.63-12.83) and lesser prevalence of EGFR mutations (OR 0.31, 95% CI: 0.16-0.59). There were a greater proportion of Hispanic smokers with KRAS mutations (14/41; 34.1%) than Asian smokers (4/58; 6.9%).We saw a greater percentage of Hispanics with KRAS mutations despite similar smoking percentages along with a greater percentage of Asians with EGFR mutations. This study shows that ethnic and racial backgrounds of the patient can influence the effects of potentially carcinogenic exposures leading to variances of mutation frequency of NSCLC among different ethnicities.

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned coprimary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported. In a randomized, open-label, phase III NEJ009 study, gefitinib plus chemotherapy significantly improved progression-free survival (PFS) and overall survival (OS) compared with gefitinib-alone in patients with untreated non–small-cell lung cancer harboring mutations in epidermal growth factor receptor. Herein, we report the updated survival outcome and long-term tolerability. Patients were randomly assigned to gefitinib (gefitinib 250 mg orally, once daily) and gefitinib combined with carboplatin plus pemetrexed (GCP in a 3-week cycle for six cycles followed by concurrent gefitinib and pemetrexed maintenance) groups. At the data cutoff (May 22, 2020), GCP demonstrated significantly better PFS2 (hazard ratio, 0.77; 95% CI, 0.62 to 0.97; P = .027) than gefitinib. However, the updated median OS was 38.5 months (95% CI, 31.1 to 47.1) and 49.0 months (95% CI, 41.8 to 56.7) in the gefitinib and GCP groups, respectively (hazard ratio, 0.82; 95% CI, 0.64 to 1.06; P = .127). The OS in both groups was similar for the overall patient population. No severe adverse events occurred since the first report. This updated analysis revealed that the GCP regimen improved PFS and PFS2 with an acceptable safety profile compared with gefitinib-alone. GCP is more efficient than gefitinib monotherapy as a first-line treatment for non–small-cell lung cancer with epidermal growth factor receptor mutations.

Extrachromosomal DNA (ecDNA) is a common mode of oncogene amplification but is challenging to analyze. Here, we adapt CRISPR-CATCH, in vitro CRISPR-Cas9 treatment and pulsed field gel electrophoresis of agarose-entrapped genomic DNA, previously developed for bacterial chromosome segments, to isolate megabase-sized human ecDNAs. We demonstrate strong enrichment of ecDNA molecules containing EGFR, FGFR2 and MYC from human cancer cells and NRAS ecDNA from human metastatic melanoma with acquired therapeutic resistance. Targeted enrichment of ecDNA versus chromosomal DNA enabled phasing of genetic variants, identified the presence of an EGFRvIII mutation exclusively on ecDNAs and supported an excision model of ecDNA genesis in a glioblastoma model. CRISPR-CATCH followed by nanopore sequencing enabled single-molecule ecDNA methylation profiling and revealed hypomethylation of the EGFR promoter on ecDNAs. We distinguished heterogeneous ecDNA species within the same sample by size and sequence with base-pair resolution and discovered functionally specialized ecDNAs that amplify select enhancers or oncogene-coding sequences.

Our previous studies have demonstrated that human papillomavirus (HPV)-16 E7 oncoprotein promoted epithelial-mesenchymal transition (EMT) in non-small cell lung cancer (NSCLC) cells. Moreover, recent studies have found that exosomes can mediate EMT of NSCLC cells and epidermal growth factor receptor (EGFR) is related to the progression of NSCLC. Here, we further investigated the role of exosomal EGFR in HPV-16 E7-induced EMT of NSCLC cells. Our results showed that the exosomes derived from the stable HPV-16 E7-overexpressing A549 and NCI-H460 NSCLC cells (E7 Exo) significantly increased migration, invasion, and proliferation abilities of NSCLC cells as compared with the exosomes derived from empty vector-infected NSCLC cells (ev Exo). Moreover, both

Purpose: Although osimertinib has excellent intracranial activity in metastatic non-small cell lung cancer (NSCLC) with exon 19 deletion or L858R EGFR alterations, measures of local control of brain metastases are less well-reported. We describe lesion-level outcomes of brain metastases treated with osimertinib alone.Methods: We retrospectively reviewed patients with EGFR-mutant NSCLC with untreated brain metastasis measuring ≥5 mm at the time of initiating osimertinib. Cumulative incidence of local recurrence in brain (LRiB) was calculated with death as a competing risk, and univariable and multivariable analyses were conducted to identify factors associated with LRiB. Results: We included 284 brain metastases from 37 patients. Median follow-up was 20.1 months. On initial MRI after starting osimertinib, patient-level response was complete response (CR) in 11 (15%), partial response (PR) in 33 (45%), stable disease (SD) in 18 (25%) and progressive disease (PD) in 11 (15%). The 1-year cumulative incidence of LRiB was 14% (95% CI 9.9-17.9) and was significantly different in patients with a CR (0%), PR (4%), and SD (11%; p=0.02). Uncontrolled primary tumor (adjusted hazard ratio [aHR] 3.78, 95% CI 1.87-7.66; ppp=0.003) were associated with LRiB. Conclusions: Although 1-year risk of LRiB is

The purpose of this study was to investigate the outcomes of gefitinib and erlotinib in patients with non-small cell lung cancer (NSCLC) with uncommon epidermal growth factor receptor (EGFR) mutations.Relevant researches were identified by a literature search of the PubMed database. Patients with EGFR mutations other than exon 19 deletion and L858R were eligible for the study. Clinical outcomes included objective response rate (ORR), progression free survival (PFS), and overall survival (OS). We categorized all uncommon EGFR mutations as: single uncommon EGFR mutations and compound mutations that containing 2 or more kinds of EGFR mutations. We also assessed outcomes in patients categorized by EGFR-TKIs: (1) gefitinib group; (2) erlotinib group.A total of 438 patients with NSCLC harboring uncommon EGFR mutations were included in this study. The ORR for gefitinib and erlotinib was 43.8 %, with a median PFS (mPFS) of 6.00 months and a median OS (mOS) of 20.50 months. Patients with compound mutations had an ORR of 56.3 % and an mPFS of 8.10 months. Both of them were significantly better than these in patients with single uncommon EGFR mutation, which were 29.3 % and 3.90 months, respectively (odds ratio (ORa): 2.74, 95 % confidence interval (CI): 1.86-4.05, P 0.001; hazard ratio (HR): 0.58, 95 % CI: 0.48-0.71, P 0.001). Moreover, patients with compound mutations containing 19 deletion or L858R had a superior response and survival benefits compared to patients with other compound mutation patterns. In addition, the gefitinib group showed a favorable efficacy advantage (P = 0.003) and PFS benefit (P = 0.021) compared to the erlotinib group.Uncommon EGFR mutations exhibit favorable but inconsistent treatment responses and survival outcomes to gefitinib and erlotinib, which are closely related to the mutation pattern, the cooccurring partner mutant genes, and the type of EGFR-TKIs received.

International audience; Objectives: To describe the impact of immune checkpoint inhibitors (ICIs) on treatment patterns and survival outcomes in patients with locally advanced or metastatic non-small cell lung cancer (aNSCLC) in France and Germany. Materials and Methods: Patients with aNSCLC without known ALK or EGFR mutations receiving first-line (1L) therapy were included from (i) the retrospective Epidemiological-Strategy and Medical Economics Advanced and Metastatic Lung Cancer cohort (ESME-AMLC, France; 2015–2018) and (ii) the prospective Clinical Research platform Into molecular testing, treatment and outcome of non-Small cell lung carcinoma Patients platform (CRISP, Germany; 2016–2018). Analyses were stratified according to histology. Survival outcomes were estimated using Kaplan–Meier methodology and stratified by year of 1L therapy. Data sources were analysed separately. Results: In ESME-AMLC and CRISP, 8,046 and 2,359 patients were included in the study, respectively. In both countries, approximately 20 % of all patients received pembrolizumab monotherapy as 1L treatment in 2018. In ESME-AMLC, the proportion receiving an ICI over the course of treatment (any line) increased from 42.2 % (2015) to 56.1 % (2018) in patients with squamous histology, and 28.9 % to 51.9 % with non-squamous/other; in CRISP, it increased from 50.6 % (2016) to 65.2 % (2018) with squamous histology, and 40.8 % to 62.7 % with non-squamous/other. Two-year overall survival from 1L initiation was 36.8 % and 25.6 % in the squamous cohorts and 36.5 % and 30.8 % in the non-squamous/other cohorts in ESME-AMLC and CRISP, respectively. No significant change in overall survival was observed over time; however, the follow-up time available was limited in the later years of the analysis. Conclusion: The results of this joint research from two large clinical databases in France and Germany demonstrate the growing use of ICIs in the management of aNSCLC. Future analyses will allow for the evaluation of the impact of ICIs on long-term survival of patients with aNSCLC.

This retrospective study aimed to estimate the incidence, risk factors of thromboembolism events (TEs) in non-small cell lung cancer patients harboring common gene mutation, and evaluate a genetic link between oncogenes and the risk of TEs in Asian patients with NSCLC.Univariate and multivariate Cox's proportional hazards regression models were used to identify the strongest predictors of TE development and evaluate the risk of TE in patients with different gene statuses of NSCLC patients.In univariate and multivariate COX analysis, patient with squamous cell carcinoma (HR 3.01, 95% CI: [1.06,8.56]; p = 0.039), multi-site metastases (HR: 2.72; 95% CI: [1.08,6.92]; p = 0.032) or high white blood cell (WBC) (HR 3.24, 95% CI: [1.46,7.22]; p = 0.004), less hemoglobin (HGB) (HR 4.89, 95% CI: [1.90,12.64]; p = 0.001), are at higher risk of thrombosis. At the molecular level, ROS and ALK rearrangement is highly associated with TE development, with HR of 4.04 (95%CI: [1.54,10.58]; p = 0.005) and HR of 3.57 (95% CI: [1.01,12.66]; p = 0.049) in univariate analysis, and even higher in multivariate analysis. EGFR mutations seem to be a protective factor against TE in univariate analyses (HR:0.28, 95%CI [0.12,0.65], p = 0.003) but are not statistically significant in the multivariate model. No correlation between KRAS mutations and TE events in both models. Besides, a numerically higher cumulative incidence of thrombosis event was observed in patients who used TKI (HR 1.473; 95% CI: [0.682, 3.181]; p = 0.32).Our study demonstrated that driver gene mutation may increase the risk of thrombosis in non-small cell lung cancer patients. The presence of ALK/ROS rearrangements in our study is associated with an approximately threefold to fourfold increase in thrombosis risk in NSCLC patients. For advanced-stage patients who used TKI, an increased incidence of thrombosis risk and shorter follow-up were observed.

Many patients with advanced lung cancer develop brain metastasis (BM); however, few reports confirming the efficacy of immune checkpoint inhibitors (ICIs) plus chemotherapy in non-small cell lung cancer (NSCLC) patients with symptomatic BM have been published. Therefore, we retrospectively evaluated the effects of chemoimmunotherapy in NSCLC patients who did or did not receive prior brain radiotherapy.A total of 103 patients with advanced NSCLC who received ICIs plus chemotherapy at our hospital from January 2019 to July 2021 were retrospectively enrolled.Patients with BM tended to have shorter progression-free survival (PFS) and overall survival (OS) compared with patients without BM. The maximum size of BM and the proportion of patients with symptomatic BM were greater among patients who received brain radiotherapy before chemoimmunotherapy. However, patients who received prior brain radiotherapy had better PFS and OS compared with patients who did not receive prior brain radiotherapy.Patients who received prior brain radiotherapy experienced a superior therapeutic benefit of ICIs plus chemotherapy, including those with larger and more symptomatic BM.

Currently, whether patients with rare epidermal growth factor receptor (EGFR) mutations could benefit from EGFR tyrosine kinase inhibitors (TKIs) demands further studies. Limited clinical data are available regarding the molecular characteristics and clinical response in non-small-cell lung cancer (NSCLC) patients harboring EGFR E709-T710delinsX mutations, a rare mutation type in exon 18 of EGFR. In this study, we aimed to explore the molecular distribution and clinical outcome of EGFR E709-T710delinsX mutated Chinese patients.Next-generation sequencing (NGS) tests were performed in 15,078 NSCLC patients. A multicenter retrospective cohort involving 17 advanced lung cancer patients with EGFR E709-T710delinsX was collected to evaluate clinical responses to diverse therapies. In silico protein structure modeling was conducted to predict drug response.5905 EGFR mutant patients (39.2%, 5905/15078) were identified, with 26 cases (0.44%, 26/5905) harbored EGFR E709-T710delinsD. Afatinib showed a better overall objective response rate (ORR) compared with the first-generation (1G) EGFR TKIs and chemotherapy with significant difference. Superior progression free survival (PFS) was also observed in patients treated with afatinib (afatinib 10.85 m vs 1G EGFR TKIs 4.0 m vs chemotherapy 2.8 m, p = 0.0007). In silico protein structure modeling predicts better binding of afatinib with EGFR E709-T710delinsD compared with other EGFR TKIs.This is the largest studies for EGFR E709-T710delinsX, with 26 cases with EGFR E709-T710delinsX being identified (0.44% in EGFR mutant NSCLC, 0.17% in NSCLC patients). This study also firstly revealed that afatinib might exert superior antitumor activity to the 1G EGFR TKIs and chemotherapy in EGFR E709-T710delinsX mutant patients.

Osimertinib is an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) used in first line for the treatment of advanced EGFR-mutated non-small cell lung cancer (NSCLC).The identification of related histomolecular resistance mechanisms to first-line osimertinib is a critical step to define the optimal treatment strategy beyond progression.All consecutive patients treated in the first line with osimertinib for advanced EGFR-mutated NSCLC at 10 hospitals in the Greater Paris area between April 2015 and January 2021 were included. Histomolecular data from plasma and tissue samples taken at progression under osimertinib were collected, and all samples were analyzed using DNA next-generation sequencing. Data on objective response rate (ORR), overall survival (OS), progression-free survival (PFS), and time to treatment discontinuation (TTD) were also collected.Overall, 104 patients were included. Most patients had adenocarcinoma (n = 102, 98%) with an exon 19 EGFR deletion (n = 54, 52%). Forty-two patients (50%) had central nervous system (CNS) metastasis at the time of osimertinib initiation. ORR was 76%, median PFS and OS were 12.6 months and 52 months, respectively, and TTD was 33 months. At the time of analysis, 44 patients (42%) had tumor progression, and among these patients, 27 (61%) contributive samples were available. The most frequent molecular alterations at progression were mesenchymal epithelial transition factor (MET) amplification (15%; n = 4) and EGFR C797S mutation (11%; n = 3). Histological transformation was found in one patient (4%). RNA next-generation sequencing was performed in eight patients and showed a CCDC6-RET fusion in one patient (12%).We confirmed the efficacy of osimertinib in patients with advanced EGFR mutation-positive NSCLC. At progression, the most frequent histomolecular alterations were MET amplification and EGFR C797S mutation.

T cell–engaging bispecific antibodies (TCB) are highly potent therapeutics that can recruit and activate cytotoxic T cells to stimulate an antitumor immune response. However, the development of TCBs against solid tumors has been limited by significant on-target toxicity to normal tissues. Probody therapeutics have been developed as a novel class of recombinant, protease-activated antibody prodrugs that are “masked” to reduce antigen binding in healthy tissues but can become conditionally unmasked by proteases that are preferentially active in the tumor microenvironment (TME). Here, we describe the preclinical efficacy and safety of CI107, a Probody TCB targeting EGFR and CD3. In vitro, the protease-activated, unmasked CI107 effectively bound EGFR and CD3 expressed on the surface of cells and induced T-cell activation, cytokine release, and cytotoxicity toward tumor cells. In contrast, dually masked CI107 displayed a >500-fold reduction in antigen binding and >15,000-fold reduction in cytotoxic activity. In vivo, CI107 potently induced dose-dependent tumor regression of established colon cancer xenografts in mice engrafted with human peripheral blood mononuclear cells. Furthermore, the MTD of CI107 in cynomolgus monkeys was more than 60-fold higher than that of the unmasked TCB, and much lower levels of toxicity were observed in animals receiving CI107. Therefore, by localizing activity to the TME and thus limiting toxicity to normal tissues, this Probody TCB demonstrates the potential to expand clinical opportunities for TCBs as effective anticancer therapies for solid tumor indications. Significance: A conditionally active EGFR-CD3 T cell–engaging Probody therapeutic expands the safety window of bispecific antibodies while maintaining efficacy in preclinical solid tumor settings.

The E3 ubiquitin ligase HECTD3 is a homologue of the E6-related protein carboxyl terminus, which plays a crucial role in biological processes and tumourigenesis. However, the functional characterisation of HECTD3 in glioblastoma is still elusive.Determination of the functional role of HECTD3 in glioblastoma was made by a combination of HECTD3 molecular pattern analysis from human glioblastoma databases and subcutaneous and in situ injections of tumours in mice models.This study reports that the DOC domain of HECTD3 interacts with the DNA binding domain of PARP1, and HECTD3 mediated the K63-linked polyubiquitination of PARP1 and stabilised the latter expression. Moreover, the Cysteine (Cys) 823 (ubiquitin-binding site) mutation of HECTD3 significantly reduced PARP1 polyubiquitination and HECTD3 was involved in the recruitment of ubiquitin-related molecules to PARP1 ubiquitin-binding sites (Lysines 209 and 221, respectively). Lastly, activation of EGFR-mediated signalling pathways by HECTD3 regulates PARP1 polyubiquitination.Our results unveil the potential role of HECTD3 in glioblastoma and strongly preconise further investigation and consider HECTD3 as a promising therapeutic marker for glioblastoma treatment.

Lenvatinib is an inhibitor of multiple receptor tyrosine kinases that was recently authorized for first-line treatment of hepatocellular carcinoma (HCC). However, the clinical benefits derived from lenvatinib are limited, highlighting the urgent need to understand mechanisms of resistance. We report here that HCC cells develop resistance to lenvatinib by activating EGFR and stimulating the EGFR–STAT3–ABCB1 axis. Lenvatinib resistance was accompanied by aberrant cholesterol metabolism and lipid raft activation. ABCB1 was activated by EGFR in a lipid raft–dependent manner, which significantly enhanced the exocytosis of lenvatinib to mediate resistance. Furthermore, clinical specimens of HCC showed a correlation between the activation of the EGFR–STAT3–ABCB1 pathway and lenvatinib response. Erlotinib, an EGFR inhibitor that has also been shown to inhibit ABCB1, suppressed lenvatinib exocytosis, and combined treatment with lenvatinib and erlotinib demonstrated a significant synergistic effect on HCC both in vitro and in vivo. Taken together, these findings characterize a mechanism of resistance to a first-line treatment for HCC and offer a practical means to circumvent resistance and treat the disease. Significance: HCC cells acquire resistance to lenvatinib by activating the EGFR–STAT3–ABCB1 pathway, identifying combined treatment with erlotinib as a strategy to overcome acquired resistance and improve the clinical benefit of lenvatinib.

Immunotherapy has shown limited efficacy in patients with EGFR-mutated lung cancer. Efforts to enhance the immunogenicity of EGFR-mutated lung cancer have been unsuccessful to date. Here, we discover that MET amplification, the most common mechanism of resistance to third-generation EGFR tyrosine kinase inhibitors (TKI), activates tumor cell STING, an emerging determinant of cancer immunogenicity (1). However, STING activation was restrained by ectonucleosidase CD73, which is induced in MET-amplified, EGFR-TKI–resistant cells. Systematic genomic analyses and cell line studies confirmed upregulation of CD73 in MET-amplified and MET-activated lung cancer contexts, which depends on coinduction of FOSL1. Pemetrexed (PEM), which is commonly used following EGFR-TKI treatment failure, was identified as an effective potentiator of STING-dependent TBK1-IRF3-STAT1 signaling in MET-amplified, EGFR-TKI–resistant cells. However, PEM treatment also induced adenosine production, which inhibited T-cell responsiveness. In an allogenic humanized mouse model, CD73 deletion enhanced immunogenicity of MET-amplified, EGFR-TKI–resistant cells, and PEM treatment promoted robust responses regardless of CD73 status. Using a physiologic antigen recognition model, inactivation of CD73 significantly increased antigen-specific CD8+ T-cell immunogenicity following PEM treatment. These data reveal that combined PEM and CD73 inhibition can co-opt tumor cell STING induction in TKI-resistant EGFR-mutated lung cancers and promote immunogenicity. Significance: MET amplification upregulates CD73 to suppress tumor cell STING induction and T-cell responsiveness in TKI-resistant, EGFR-mutated lung cancer, identifying a strategy to enhance immunogenicity and improve treatment.

While the role of G-protein–coupled receptors (GPCR) in cancer is acknowledged, their underlying signaling pathways are understudied. Protease-activated receptors (PAR), a subgroup of GPCRs, form a family of four members (PAR1–4) centrally involved in epithelial malignancies. PAR4 emerges as a potent oncogene, capable of inducing tumor generation. Here, we demonstrate identification of a pleckstrin-homology (PH)-binding motif within PAR4, critical for colon cancer growth. In addition to PH–Akt/PKB association, other PH-containing signal proteins such as Gab1 and Sos1 also associate with PAR4. Point mutations are in the C-tail of PAR4 PH-binding domain; F347 L and D349A, but not E346A, abrogate these associations. Pc(4–4), a lead backbone cyclic peptide, was selected out of a mini-library, directed toward PAR2&4 PH-binding motifs. It effectively attenuates PAR2&4–Akt/PKB associations; PAR4 instigated Matrigel invasion and migration in vitro and tumor development in vivo. EGFR/erbB is among the most prominent cancer targets. AYPGKF peptide ligand activation of PAR4 induces EGF receptor (EGFR) Tyr-phosphorylation, effectively inhibited by Pc(4–4). The presence of PAR2 and PAR4 in biopsies of aggressive breast and colon cancer tissue specimens is demonstrated. We propose that Pc(4–4) may serve as a powerful drug not only toward PAR-expressing tumors but also for treating EGFR/erbB-expressing tumors in cases of resistance to traditional therapies. Overall, our studies are expected to allocate new targets for cancer therapy. Pc(4–4) may become a promising candidate for future therapeutic cancer treatment.

Serine peptidase inhibitor Kazal type-1 (SPINK1), a trypsin kinase inhibitor, is known to be associated with inflammation and pathogenesis. The aim in this study was to demonstrate the clinicopathological role and progression of SPINK1 in rectal cancer (RC) patients undergoing concurrent chemoradiotherapy (CCRT). Immunohistochemical staining for SPINK1 protein expression in 111 RC cases revealed high SPINK1 expression was significantly associated with perineural invasion and poor CCRT response in pre-CCRT specimens. In addition, multivariable analyses showed that pre-CCRT SPINK1 expression was a significant prognostic marker of both overall and disease-free survival in RC patients receiving pre-operative CCRT; furthermore, in vitro studies demonstrated SPINK1 interacted with EGFR to promote the abilities of proliferation, migration and invasion attenuated by SPINK1 si-RNA via ERK, p38, and JNK pathways. SPINK1 was also found to regulate radio-resistance in CRC cell lines. In conclusion, SPINK1 expression is an independent prognostic marker in patients receiving pre-operative CCRT, and SPINK1 regulates proliferation, migration and invasion via EGFR-downstream ERK, p38 and JNK pathways. The phenotypes of radiosensitivity that could be reversed with attenuation of SPINK1 levels suggest that targeting SPINK1 might offer a strategy for optimal precision medicine.

Head and neck squamous cell carcinomas are rising in incidence worldwide, and despite the advent of improved surgical and radiation techniques, a substantial proportion of patients have disease recurrence, where systemic therapies are the mainstay of management. Recent advances in systemic therapy include the development of epidermal growth factor receptor- and programmed death 1-targeting drugs, which have produced incremental improvements in disease outcomes. However, for most patients, responses to treatment remain elusive because of primary or acquired resistance. Novel drugs and rational drug combinations need to be tested based on biomarker identification and preclinical science that will ultimately advance outcomes for our patients. This review focuses on efforts untaken for epidermal growth factor receptor targeting in head and neck squamous cell carcinoma to date.

Background: Gastric cancer (GC) is the fourth most commonly found cancer and the second- highest cause of cancer-related death worldwide. TROP2 overexpression is closely related to many cancers, including gastrointestinal tumors. DSG2 is an important protein in cell adhesion, and its loss affects cell migration. Aims and Objective: This study aimed to explore the specific mechanism of TROP2 in promoting gastric cancer and provide a basis for the prevention and treatment of gastric cancer. Method: DSG2 was identified as an interacting protein of TROP2 in GC cells by coimmunoprecipitation and mass spectrometry. The regulated behavior of TROP2 on DSG2 expression was investigated with TROP2 over-expressure or knockdown. Cell-cell adhesion capacity mediated by DSG2 was evaluated by adhesion-related assays. Electron microscope observation was made for accessing GC tumor desmosome assembly. Proteins in EGFR/AKT and DSG2/PG/β-catenin pathways were evaluated by western blotting. Result: This study suggests that abundant expression of TROP2 in GC cells lessened DSG2 levels as well as desmosome adhesion, increased cell invasion and migration, and promoted malignant progression through EGFR/AKT and DSG2/PG/β-catenin pathways. Conclusion: TROP2 promotes cell invasion and migration in gastric cancer by decreasing DSG2 expression through EGFR/AKT and DSG2/PG/β-catenin pathways.

In ORIENT-11, first-line sintilimab + pemetrexed-platinum significantly improved PFS compared with placebo + pemetrexed-platinum in patients with advanced metastatic nonsquamous non-small-cell lung cancer (AMnsqNSCLC). The study met the primary endpoint of PFS as of 15November2019. Here we report final survival analysis from ORIENT-11 (NCT03607539) using a 15September2021 data cutoff.Patients with treatment-naïve locally AMnsqNSCLC without sensitizing EGFR or ALK genomic tumor aberrations were randomly assigned to sintilimab + pemetrexed-platinum (n = 266) or placebo + pemetrexed-platinum (n = 131). Patients were stratified by PD-L1 expression, platinum-chemotherapy, and gender. Treatment continued until PD, unacceptable toxicity, or a maximum of 24 months. Patients in the placebo + pemetrexed-platinum arm could be sequenced to second-line sintilimab monotherapy, contingent upon PD. Response was assessed (RECISTv.1.1) by blinded independent radiographic review committee. Primary endpoint was PFS. OS was a secondary endpoint and defined from date of randomization to date of death due to any cause. Final OS analysis was defined as approximately 2 years after last patient randomized or when approximately 65 % of patients died, whichever first.At data cutoff of final OS analysis, median study follow-up was 30.8 months. Of 397 patients, 243 OS events were observed (sintilimab + pemetrexed-platinum:151[57 %];placebo + pemetrexed-platinum:92 [70 %]). Of the patients in placebo + pemetrexed-platinum arm, 47 % crossed over to sintilimab monotherapy per protocol. Median OS was 24.2 months in sintilimab + pemetrexed-platinum arm and 16.8 months in placebo + pemetrexed-platinum arm (HR:0.65[95 % CI:0.50,0.85]). Estimated 2-year OS rates were 50 %(sintilimab + pemetrexed-platinum) and 32 %(placebo + pemetrexed-platinum). After adjusting for the crossover effect, OS treatment effect was more pronounced with HR 0.52 (95 % CI:0.38,0.69). OS benefit across all prespecified subgroups was largely consistent with that observed in the ITT population.In the ORIENT-11 final OS analysis, sintilimab + pemetrexed-platinum demonstrated improved OS compared to placebo + pemetrexed-platinum when administered as first-line therapy in AMnsqNSCLC without EGFR or ALK genomic tumor aberrations.

Non-small-cell lung cancer (NSCLC) had poor prognosis in patients with brain metastasis. The trial evaluated the safety and efficacy of epitinib (HMPL-813), an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), for EGFR-mutant NSCLC with brain metastasis.This open-label, dose-expansion phase Ib study (ClinicalTrials.gov: NCT02590952) was conducted at 7 Chinese centers and enrolled patients with EGFR-mutant advanced NSCLC with brain metastasis. Epitinib was administered at 120 mg or 160 mg, orally QD. The primary endpoint was safety and tolerability.Between April 2015 and April 2019, 72 patients were enrolled and received epitinib at 120 mg (n = 30) or 160 mg (n = 42). Treatment-related adverse events (TRAEs) of grade ≥3 occurred in 13 (43.3%) patients in 120 mg group and 21 (50.0%) in 160 mg group. The objective response rate (ORR) was 53.6% (95% CI 33.9%-72.5%) in 120 mg group and 40.5% (25.6%-56.7%) in 160 mg group. The median duration of response in the 120 mg and 160 mg groups were 7.40 months (95% CI 3.70-7.40) and 9.10 months (6.50-12.00), respectively. The median progression-free survival were 7.40 months (95% CI 5.40-9.20) and 7.40 months (5.50-10.00), respectively.In patients with EGFR-mutant NSCLC with brain metastasis, epitinib was well tolerable with a promising efficacy. According to the comprehensive assessment on safety and efficacy, 160 mg QD could be the recommended phase 2 dose.

Background: This study intended to investigate the mechanisms underlying the epidermal growth factor receptor (EGFR) mutations in nonsmall cell lung cancer (NSCLC). Materials and Methods: Lung cancer tissue samples were collected from 20 patients with NSCLC (6 EGFR mutation types assigned into 2 categories and 14 EGFR wild types assigned to 4 categories). The samples were subjected to transcriptome sequencing, followed by identification of the differentially expressed mRNAs (DEMs), differentially expressed lncRNAs (DELs), and differentially expressed circRNAs (DECs) between the mutation and nonmutation groups. Function analysis and microRNA (miRNA) prediction for DEMs were performed. The correlations between long noncoding RNA (lncRNA)/circular RNA (circRNA) and messenger RNA (mRNA) were analyzed. In addition, the targeting lncRNA and circRNA of miRNA were predicted. Finally, competing endogenous RNA (ceRNA) network was constructed, and survival analysis for the mRNAs involved in the network was performed. Results: In total, 323 DEMs, 284 DELs, and 224 DECs were identified between EGFR mutation and nonmutation groups. The DEMs were significantly involved in gene ontology functions related to cilium morphogenesis and assembly. ceRNA networks were constructed based on the DEMs, DELs, DECs, and predicted miRNAs. Survival analysis showed that four genes in the ceRNA network, including ABCA3, ATL2, VAMP1, and APLN, were significantly associated with prognosis. The four genes were involved in several ceRNA pathways, including RP1-191J18/circ_000373/miR-520a-5p/ABCA3, RP5-1014D13/let-7i-5p/ATL2, circ_000373/miR-1293/VAMP1, and RP1-191J18/circ_000373/miR-378a-5p/APLN. Conclusion: EGFR mutations in NSCLC may be associated with cilium dysfunction and complex ceRNA regulatory mechanisms. The key RNAs in the ceRNA network may be used as promising biomarkers for predicting EGFR mutations in NSCLC.

PURPOSE Subset analyses from phase III evaluation of epidermal growth factor receptor inhibition (EGFRi) suggest improved outcomes in patients with EGFR-amplified gastroesophageal adenocarcinoma (GEA), but large-scale analyses are lacking. This multi-institutional analysis sought to determine the role of EGFRi in the largest cohort of patients with EGFR-amplified GEA to date. PATIENTS AND METHODS A total of 60 patients from 15 tertiary cancer centers in six countries met the inclusion criteria. These criteria required histologically confirmed GEA in the metastatic or unresectable setting with EGFR amplification identified by using a Clinical Laboratory Improvement Amendments–approved assay, and who received on- or off-protocol EGFRi. Testing could be by tissue next-generation sequencing, plasma circulating tumor DNA next-generation sequencing, and/or fluorescence in situ hybridization performed by a Clinical Laboratory Improvement Amendments approved laboratory. Treatment patterns and outcomes analysis was also performed using a deidentified clinicogenomic database (CGDB). RESULTS Sixty patients with EGFR-amplified GEA received EGFRi, including 31 of 60 patients (52%) with concurrent chemotherapy. Across treatment lines, patients achieved a 43% objective response rate with a median progression-free survival of 4.6 months (95% CI, 3.5 to 6.4). Patients receiving EGFRi in first-, second-, and third-line therapy achieved a median overall survival of 20.6 months (95% CI, 13.5 to not reached [NR]), 9 months (95% CI, 7.9 to NR), and 8.4 months (7.6 to NR), respectively. This survival far exceeded the 11.2-month (95% CI, 8.7 to 14.2) median overall survival from first-line initiation of non-EGFRi therapy in patients with EGFR-amplified GEA in the CGDB. Despite this benefit, analysis of the CGDB (January 2011-December 2020) suggests that only 5% of patients with EGFR-amplified GEA received EGFRi. CONCLUSION Patients with EGFR-amplified GEA derive significant benefit from EGFRi. Further prospective investigation of EGFRi in a well-selected patient population is ongoing in an upcoming trial of amivantamab in EGFR and/or MET amplified GEA.

Target expression heterogeneity and the presence of an immunosuppressive microenvironment can hamper severely the efficiency of immunotherapeutic approaches. We have analyzed the potential to encounter and overcome such conditions by a combinatory two-target approach involving a bispecific antibody retargeting T cells to tumor cells and tumor-directed antibody-fusion proteins with costimulatory members of the B7 and TNF superfamily. Targeting the tumor-associated antigens EpCAM and EGFR with the bispecific antibody and costimulatory fusion proteins, respectively, we analyzed the impact of target expression and the influence of the immunosuppressive factors IDO, IL-10, TGF-β, PD-1 and CTLA-4 on the targeting-mediated stimulation of T cells. Here, suboptimal activity of the bispecific antibody at diverse EpCAM expression levels could be effectively enhanced by targeting-mediated costimulation by B7.1, 4-1BBL and OX40L in a broad range of EGFR expression levels. Furthermore, the benefit of combined costimulation by B7.1/4-1BBL and 4-1BBL/OX40L was demonstrated. In addition, the expression of immunosuppressive factors was shown in all co-culture settings, where blocking of prominent factors led to synergistic effects with combined costimulation. Thus, targeting-mediated costimulation showed general promise for a broad application covering diverse target expression levels, with the option for further selective enhancement by the identification and blockade of main immunosuppressive factors of the particular tumor environment., Deutsche Krebshilfe, Projekt DEAL

EGFR inhibitors used in the treatment of metastatic wild-RAS colorectal cancer in combination with chemotherapy are associated with dermatologic side events that are low grade in most cases. We report a case of severe cutaneous toxicity secondary to cetuximab associated with bacterial cellulitis. A 57-year-old woman with metastatic adenocarcinoma of the colon, receiving FOLFIRI and Cetuximab as a first-line treatment, presented with a severe erythematous rash and xerosis resistant to local treatment with moisturizing emollients. Few days later, the patient becomes febrile, and the rash becomes more diffuse with a sandpaper appearance on the face, neck, chest, and flexor creases with exfoliation of large areas of skin. A bacterial cellulitis secondary to a dermatologic severe toxicity of Cetuximab was suspected. The patient started on antibiotics and local treatment with good response. This is a life-threatening cutaneous toxicity of cetuximab with secondary bacterial infection. Early recognition of cutaneous side effects of EGFR inhibitors is important to prevent such type of toxicities.

Fibroblast growth factor receptor inhibitors (FGFRi) were introduced into clinical trials on several cancer types and found to be particularly efficacious on urothelial cancer and cholangiocarcinoma. Although many enrolled patients responded well in clinical trials, there were some patients who did not respond to FGFRi even though their tumors carried the genomic changes that met the enrollment criteria. As already established, fibroblast growth factor receptor (FGFR) and epidermal growth factor receptor (EGFR) share the downstream signaling pathway of MAPK activation. Accordingly, it is conceivable that targeted inhibition of FGFR alone could leave the MAPK signaling unaffected when the signaling through EGFR is relatively strong. To test this hypothesis, we calculated here the FGFR to EGFR mRNA ratio (F/E for short) of biliary tract and urothelial cancer cell lines utilized in preclinical studies. In six biliary tract cancer cell lines, two responsive lines had an F/E of 9.5 and 9.0, whereas the F/E of four nonresponsive lines was 0.1-1.8. In 22 urothelial cancer cell lines, four of the five responsive lines showed an F/E of 2.8-4.9 (median, 3.6), whereas the F/E range of 17 nonresponsive lines was 0.01-2.7 (median, 0.6) (p = 0.004). We further investigated our 47 patient-derived colorectal cancer-stem cell spheroid lines. The 18 responsive lines showed relatively high F/E (median, 16.4), whereas 29 nonresponsive lines had low F/E (median, 9.2) (p = 0.0006). These results suggest that F/E is another strong predictor of responses to FGFRi that is as useful as the current genomic criteria based solely on the FGFR genomic changes.

To identify liquid biomarkers that predict clinical outcomes of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI), we enrolled patients with EGFR gene mutation-positive non-small-cell lung cancer who were intended to receive gefitinib treatment. Using plasma samples obtained prior to gefitinib treatment from 12 enrolled patients, we performed comprehensive proteomic analysis of plasma exosomes to explore proteins correlating with tumor reduction rate (TRR), progression-free survival (PFS), or overall survival (OS). Of the detected 1769 proteins, 119, 130, or 119 proteins demonstrated a strong correlation (|r| 0.5) with TRR, PFS, or OS, respectively. Interestingly, 34 (29%), 41 (32%), or 27 (23%) of them, respectively, were functionally involved in the regulation of the immune response. CD8α chain was consistently listed as a molecule positively correlated with PFS and OS, suggesting that the long-lasting effects of gefitinib may be due to the antitumor effects of CD8

Osimertinib (AZD9291) is a third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), used for treating patients with advanced non-small-cell lung cancer (NSCLC) harboring EGFR-activating mutations or the resistant T790M mutation. However, acquired resistance to osimertinib is inevitable in EGFR-mutant NSCLC. By employing a global mass spectrometry-based phosphoproteomics approach, we identified that the activated p21-activated kinase 2 (PAK2)/β-catenin axis acts as a driver of osimertinib resistance. We found that PAK2 directly phosphorylates β-catenin and increases the nuclear localization of β-catenin, leading to the increased expression and transcriptional activity of β-catenin, which in turn enhances cancer stem-like properties and osimertinib resistance. Moreover, we revealed that HER3 as an upstream regulator of PAK2, drives the activation of PAK2/β-catenin pathways in osimertinib-resistant cells. The clinical relevance of these findings was further confirmed by examining tissue specimens from patients with EGFR-mutant NSCLC. The results demonstrated that the levels of HER3, phospho-PAK2 (p-PAK2) and β-catenin in the tissues from patients with EGFR-mutant NSCLC, that had relapsed after treatment with osimertinib, were elevated compared to those of the corresponding untreated tissues. Additionally, the high levels of HER3, p-PAK2 and β-catenin correlated with shorter progression-free survival (PFS) in patients with EGFR-TKI-treated NSCLC. We additionally observed that the suppression of PAK2 via knockdown or pharmacological targeting with PAK inhibitors markedly restored the response of osimertinib-resistant NSCLC cells to osimertinib both in vitro and in vivo. In conclusion, these results indicated that the PAK2-mediated activation of β-catenin is important for osimertinib resistance and targeting the HER3/PAK2/β-catenin pathway has potential therapeutic value in NSCLCs with acquired resistance to osimertinib.

Under the continuous stimulation of tumor antigen in the tumor microenvironment, CD8+T cells will enter a state of functional defect or failure, which cannot effectively prevent the progression of lung cancer. Therefore, finding potential targets for immunotherapy in lung cancer has broad prospects.In the early stage of this study, the genes related to immune infiltration in lung cancer were found through the analysis on multiple datasets (GSE116959, GSE139032 and GSE111894). Characteristics of candidate genes were identified from transcriptome, methylation, single cell sequencing and other dimensions, respectively. Moreover, the correlation between candidate genes and immunotherapy-related genes and mutated genes of lung cancer was further identified. Finally, the expression of the candidate genes was detected with an online immunohistochemistry database.According to the above research, it was found that CCL4 (chemokine (C-C motif) ligand 4) was abnormally highly expressed in samples from patients with NSCLC and had certain methylation characteristics. In addition, CCL4 was also closely associated with infiltration of immune cells, such as B cells and CD8+T cells. Interestingly, the aberrant expression of CCL4 affected the survival of CD8+T cells. Single cell sequencing results also showed that CCL4 was highly expressed in CD8+T cells and was involved in biological functions such as generation cycle. Finally, CCL4 expression was positively associated with PD-1 and PD-L1, and also with mutant genes, such as EGFR, ALK and ROS1, associated with the treatment for lung cancer.CCL4 may be a potential target for immunotherapy in patients with NSCLC.

Despite a global pandemic that continued to inflict chaos and confusion on the world, resulting in fewer cancer screenings and delayed surgeries, remarkable lung cancer treatment advancements were made in 2021. From immunotherapy in the adjuvant setting to the approval of the first-in-class, highly selective inhibitor of KRAS G12C, these treatment advances have significant clinical impact in patients with lung cancer. LAY SUMMARY: There has been tremendous innovation in the treatment of nonsmall cell lung cancer. The year 2021 was marked by new approaches to adjuvant therapy and the availability of agents to target new subsets of nonsmall cell lung cancer.

Purpose Circulating tumour cells (CTCs) are a rare cell subpopulation regulated by the tumour microenvironment. In hypoxic conditions, CTCs are able to invade the lymphatic and circulatory systems leading to metastasis at distant sites. Methods To mimic in vivo oxygen variations and effects on CTCs, we have cultured five non-small cell lung cancer (NSCLC) cell lines under normoxic and hypoxic conditions, followed by a pulse of reoxygenation for 4 h. Results Proliferation, spheroid-formation and colony formation ability under varying O2 levels were investigated. Proliferation rate was not altered when cells were cultured in 2D models under hypoxic conditions. However, we observed that hypoxia enhanced in vitro formation of tumour-spheres and accelerated clonogenicity of NSCLC cell lines. In addition, cells exposed to hypoxia and reoxygenation conditions showed altered expression of epithelial-mesenchymal transition (EMT) related genes in NSCLC cell lines both at mRNA (AKT1, CAMK2NH1, DESI1, VIM, MAP1B, EGFR, ZEB1, HIF1α) and protein levels (Vimentin, Pan-cytokeratin). Conclusion Our data suggest that when investigating CTCs as a prognostic biomarker in NSCLC, it is also essential to take into consideration EMT status to obtain a comprehensive overview of CTCs in circulation.

Mutations in oncogenes such as KRAS and EGFR cause a high proportion of lung cancers. Drugs targeting these proteins cause tumor regression but ultimately fail to elicit cures. As a result, there is an intense interest in how to best combine targeted therapies with other treatments, such as immunotherapies. However, preclinical systems for studying the interaction of lung tumors with the host immune system are inadequate, in part due to the low tumor mutational burden in genetically engineered mouse models. Here we set out to develop mouse models of mutant KRAS–driven lung cancer with an elevated tumor mutational burden by expressing the human DNA cytosine deaminase, APOBEC3B, to mimic the mutational signature seen in human lung cancer. This failed to substantially increase clonal tumor mutational burden and autochthonous tumors remained refractory to immunotherapy. However, establishing clonal cell lines from these tumors enabled the generation of an immunogenic syngeneic transplantation model of KRAS-mutant lung adenocarcinoma that was sensitive to immunotherapy. Unexpectedly, antitumor immune responses were not directed against neoantigens but instead targeted derepressed endogenous retroviral antigens. The ability of KRASG12C inhibitors to cause regression of KRASG12C -expressing tumors was markedly potentiated by the adaptive immune system, highlighting the importance of using immunocompetent models for evaluating targeted therapies. Overall, this model provides a unique opportunity for the study of combinations of targeted and immunotherapies in immune-hot lung cancer.Significance:This study develops a mouse model of immunogenic KRAS-mutant lung cancer to facilitate the investigation of optimal combinations of targeted therapies with immunotherapies.

Erlotinib is a first-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). Overcoming erlotinib resistance is crucial to improve the survival of advanced non-small cell lung cancer (NSCLC) patients with sensitive EGFR mutations. It is also an important clinical problem that urgently needs a solution. In this study, we explored strategies to overcome erlotinib resistance from the perspective of energy metabolism. SIRT6 is a histone deacetylase. Here, we found that high expression of SIRT6 is associated with poor prognosis of lung adenocarcinoma, especially in EGFR-mutated NSCLC patients. The next cell experiment found that SIRT6 expression increased in erlotinib-resistant cells, and SIRT6 expression was negatively correlated with the sensitivity of NSCLC to erlotinib. Inhibition of SIRT6 promoted erlotinib-induced apoptosis in erlotinib-resistant cells, and glycolysis in drug-resistant cells was also inhibited. Functional studies have shown that SIRT6 increases glycolysis through the HIF-1α/HK2 signaling axis in drug-resistant cells and inhibits the sensitivity of NSCLC cells to erlotinib. In addition, the HIF-1α blocker PX478-2HCL attenuated the glycolysis and erlotinib resistance induced by SIRT6. More importantly, we confirmed the antitumor effect of SIRT6 inhibition combined with erlotinib in NSCLC-bearing mice. Our findings indicate that the cancer metabolic pathway regulated by SIRT6 may be a new target for attenuating NSCLC erlotinib resistance and has potential as a biomarker or therapeutic target to improve outcomes in NSCLC patients.

The types of epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) patients who could obtain significant clinical benefit from the dual inhibition of EGFR/vascular EGFR (VEGFR) pathways remain unclear. No consensus has been reached on the significance of smoking habits in clinical benefit obtained from EGFR-TKI plus anti-angiogenic agents.PubMed, EMBASE, and Cochrane databases for all phase II/III randomized clinical trials (RCTs) investigating the efficacy of EGFR-TKI combined with anti-angiogenic agents stratified by smoking habits (updated October 2021) were searched systematically. The primary outcomes were the pooled HRs for PFS/OS in smokers and non-smokers, and differences in efficacy of EGFR-TKI plus anti-angiogenic treatment between smokers and non-smokers, measured by difference in PFS and OS.Seven phase II/III RCTs involving 1452 patients were identified. The pooled analysis demonstrated that EGFR-TKI plus anti-angiogenic agent could decrease the risk of progression by 40% (HR, 0.60; 95%CI 0.48-0.75) in smokers when compared with EGFR-TKI alone, but not in non-smokers (HR, 0.92; 95%CI 0.68-1.25). The comparison analysis further demonstrated that EGFR-mutated NSCLC patients who smoked obtained greater progression-free survival (PFS) benefit from treatment with EGFR-TKI plus anti-angiogenic agents (HR, 0.68; 95%CI 0.51-0.91). Consistent with the results for PFS, smokers receiving EGFR-TKI plus anti-angiogenic agents appeared to exhibit better overall survival (OS) than non-smokers but not to a statistically significant degree (HR, 0.60; 95%CI 0.23-1.52). Meta-regression analysis revealed no significant effect of the line of treatment (P = 0.52), trial phase (P = 0.52), EGFR-TKI type (P = 0.13), or anti-angiogenic agent type (P = 0.50) on PFS effect sizes under multivariate models.Comprehensive analysis suggested that EGFR-TKI plus anti-angiogenic agents led to favorable PFS among smoking EGFR-mutant patients, comparable to nonsmokers, which might provide a useful guide for clinicians.

Background Adjuvant immune checkpoint blockade (ICB) following chemoradiotherapy and adding ICB to chemotherapy have been key advances for stages III-IV non-small cell lung cancer (NSCLC) treatment. However, known biomarkers like PD-L1 are not consistently indicative of ICB response. Other markers within the tumor immune microenvironment (TIME) may better reflect ICB response and/or resistance mechanisms, but an understanding of how TIMEs differ between stage III and IV NSCLC has not been explored. Methods Real-world data from unresectable, stage III-IV, non-squamous, pretreatment NSCLCs (stage III n = 106, stage IV n = 285) were retrospectively analyzed. PD-L1 immunohistochemistry (IHC) was compared to CD274 gene expression. Then, differential gene expression levels, pathway enrichment, and immune infiltrate between stages were calculated from whole-transcriptome RNA-seq. Analyses were stratified by EGFR status. Results PD-L1 IHC and CD274 expression in tumor cells were highly correlated (n = 295, P ⍴ = 0.74). CTLA4 expression was significantly increased in stage III tumors (P = 1.32e-04), while no differences were observed for other ICB-related genes. Metabolic pathway activity was significantly enriched in stage IV tumors (P = 0.004), whereas several immune-related KEGG pathways were enriched in stage III. Stage IV tumors had significantly increased macrophage infiltration (P = 0.0214), and stage III tumors had a significantly higher proportion of CD4 + T cells (P = 0.017). CD4 + T cells were also relatively more abundant in EGFR-mutant tumors vs. wild-type (P = 0.0081). Conclusion Directly comparing the TIMEs of stage III and IV NSCLC, these results carry implications for further studies of ICB response in non-resectable stage III NSCLC and guide further research of prognostic biomarkers and therapeutic targets.

Next-generation sequencing (NGS) assays can sensitively detect somatic variation, and increasingly can enable the identification of complex structural rearrangements. A subset of infantile spindle cell sarcomas, particularly congenital mesoblastic nephromas with classic or mixed histology, have structural rearrangement in the form of internal tandem duplications (ITD) involving EGFR. We performed prospective analysis to identify EGFR ITD through clinical or research studies, as well as retrospective analysis to quantify the frequency of EGFR ITD in pediatric sarcomas. Within our institution, three tumors with EGFR ITD were prospectively identified, all occurring in patients less than 1 year of age at diagnosis, including two renal tumors and one mediastinal soft tissue tumor. These three cases exhibited both cellular and mixed cellular and classic histology. All patients had no evidence of disease progression off therapy, despite incomplete resection. To extend our analysis and quantify the frequency of EGFR ITD in pediatric sarcomas, we retrospectively analyzed a cohort of tumors (n = 90) that were previously negative for clinical RT-PCR-based fusion testing. We identified EGFR ITD in three analyzed cases, all in patients less than 1 year of age (n = 18; 3/18, 17%). Here we expand the spectrum of tumors with EGFR ITD to congenital soft tissue tumors and report an unusual example of an EGFR ITD in a tumor with cellular congenital mesoblastic nephroma histology. We also highlight the importance of appropriate test selection and bioinformatic analysis for identification of this genomic alteration that is unexpectedly common in congenital and infantile spindle cell tumors.

Introduction: Exposure to osimertinib, a third generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) for treatment of non-small cell lung cancer (NSCLC) and a sensitizing EGFR mutation, can be substantially below average. We evaluated whether plasma levels could be boosted by co-administration of cobicistat, a strong Cytochrome P450 3A-inhibitor. Methods: This was a pharmacokinetic, proof-of-concept clinical trial (the OSIBOOST trial, NCT03858491). NSCLC-patients with osimertinib were eligible if their steady state osimertinib plasma trough concentration was low (≤195 ng/mL). On day 1, the area under the plasma curve (AUC0-24,ss) of osimertinib and its metabolite (AZ5104) was calculated using a limited sampling strategy (four samples). Cobicistat co-treatment (150 mg, once daily) was started on day 2. Between day 22–26, a second AUC was determined. Cobicistat dose could be escalated if the osimertinib trough concentration was still ≤ 195 ng/mL, in the absence of toxicity. Primary endpoint was the increase in osimertinib exposure, secondary endpoint was toxicity. Cobicistat could be continued during the expanded access phase, with follow-up (2–4 months) of the boosting effect. Results: The mean baseline osimertinib trough concentration for the eleven enrolled patients was 154 ng/mL. In all patients, cobicistat addition led to an increase in osimertinib exposure. Mean increase in total AUC0-24ss (AUC osimertinib + AUC AZ5104) was 60%, (range 19%–192%). The boosting effect was consistent over time. No grade ≥ 2 toxicity was observed. Conclusion: Pharmacokinetic boosting of osimertinib with cobicistat in patients with NSCLC is feasible without increasing toxicity, although the degree of boosting is variable.

Resistance to epidermal growth factor receptor (EGFR)/anaplastic lymphoma kinase (ALK)-tyrosine kinase inhibitors (TKIs) is a pervasive barrier in TKIs therapy for EGFR/ALK-positive non-small cell lung cancer (NSCLC) patients. Immune checkpoint inhibitor (ICI) monotherapy has exhibited an encouraging anti-tumor activity in high-selected EGFR/ALK-positive NSCLC patients with acquired resistance to TKI therapy. However, the effect of ICI plus chemotherapy therapy on those with brain metastases in this subset of patients is still unknown.From April 2019 to August 2021, EGFR-mutated or ALK-rearranged NSCLC patients who progressed after previous EGFR/ALK-TKIs with brain metastases and received ICI plus chemotherapy ± bevacizumab at Cancer Hospital of the Chinese Academy of Medical Sciences (CAMS) were included. We retrospectively analyzed the efficacy, toxicity and progression site after ICI treatment.A total of 19 patients were included in the study, including 16 (84.4%) patients with EGFR mutations, 2 (10.5%) with ALK translocations and 1 (5.3%) with RET rearrangement. All of the patients progressed after previous TKI therapy and had brain metastatic lesions when received ICI combination therapy. The overall response rate (ORR) and disease control rate (DCR) were 15.8 and 57.9%, respectively. The median progression-free survival (PFS) and overall survival (OS) were 4.7 months (95% confidence interval CI 0.43-8.96) and 19.2 months (95% CI 15.08-23.29), respectively. The intracranial ORR was 10.5% and extracranial ORR was 15.8%, and the intracranial and extracranial DCR were 68.4 and 63.2%, respectively. The most common progression pattern was extracranial failure, and primary lesions enlargement rather than new sites metastases accounted for the vast majority of progressions. The most common grade 3-4 adverse event (AE) was leukopenia (31.6%), followed by neutropenia (26.3%), thrombocytopenia (10.5%) and rash (5.3%) successively. No grade 5 AE and discontinuation of ICI therapy for severe AEs were observed.ICI combined with chemotherapy ± bevacizumab might be effective and safe for EGFR/ALK-positive NSCLC patients who progressed after previous TKI therapy, and synergistic anti-tumor activity for brain metastases was also observed.

Purpose: Liquid biopsy offers an attractive platform for noninvasive tumor diagnosis, prognostication, and prediction of glioblastoma clinical outcomes. Prior studies report that 30% to 50% of GBM lesions characterized by EGFR amplification also harbor the EGFRvIII mutation. Experimental Design: A novel digital droplet PCR (ddPCR) assay for high GC content amplicons was developed and optimized for sensitive detection of EGFRvIII in tumor tissue and circulating extracellular vesicle RNA (EV RNA) isolated from the plasma of patients with glioma. Results: Our optimized qPCR assay detected EGFRvIII mRNA in 81% [95% confidence interval (CI), 68%–94%] of EGFR-amplified glioma tumor tissue, indicating a higher than previously reported prevalence of EGFRvIII in glioma. Using the optimized ddPCR assay in discovery and blinded validation cohorts, we detected EGFRvIII mutation in 73% (95% CI, 64%–82%) of patients with a specificity of 98% (95% CI, 87%–100%), compared with qPCR tumor tissue analysis. In addition, upon longitudinal monitoring in 4 patients, we report detection of EGFRvIII in the plasma of patients with different clinical outcomes, rising with tumor progression, and decreasing in response to treatment. Conclusions: This study demonstrates the feasibility of detecting EGFRvIII mutation in plasma using a highly sensitive and specific ddPCR assay. We also show a higher than previously reported EGFRvIII prevalence in glioma tumor tissue. Several features of the assay are favorable for clinical implementation for detection and monitoring of EGFRvIII-positive tumors.

Purpose In RELAY, ramucirumab plus erlotinib (RAM + ERL) improved progression-free survival (PFS) in patients with untreated, metastatic, EGFR-mutated, non-small cell lung cancer (NSCLC). Here, we present the exposure–response relationship of RAM from RELAY. Methods Patients received ERL (150 mg/day) with either RAM (10 mg/kg) or placebo (PBO + ERL) every 2 weeks (Q2W). A population pharmacokinetic model predicted RAM minimum concentration after first dose (Cmin,1), and at steady state (Cmin,ss), which were used to evaluate correlation between RAM exposure and efficacy and safety. The Kaplan–Meier method and Cox regression analyses were utilized to evaluate exposure–efficacy by Cmin,1 quartile. Exposure–safety was evaluated by assessing incidence rates for safety parameters by Cmin,ss quartile, with ordered categorical analysis used for ALT/AST only. Results Analyses included 216 patients treated with RAM + ERL and 225 patients treated with PBO + ERL. Adjusting for significant baseline covariates, no exposure–efficacy relationship was identified in RELAY: PFS hazard ratio (mean, 95% confidence intervals) for the Cmin,1 quartiles were 0.67 (0.45–0.99), 0.77 (0.53–1.12), 0.57 (0.38–0.84), and 0.50 (0.33–0.76). No apparent exposure–safety relationship was observed for selected safety endpoints, including Grade ≥ 3 hypertension, diarrhea, and dermatitis acneiform, and any grade hypertension, any grade and Grade ≥ 3 proteinuria, and any grade ALT/AST increased within liver failure/liver injury. Conclusions No association was observed between RAM exposure and response, suggesting that the RELAY regimen of RAM 10 mg/kg Q2W with ERL is an optimized, efficacious, and safe first-line treatment for patients with untreated, metastatic, EGFR-mutated NSCLC. Trial registration: ClinicalTrials.gov, NCT02411448.

Purpose The role of epidermal growth factor receptor–tyrosine kinase inhibitors (EGFR-TKIs) in the management of persistent subsolid nodules (SSNs) is unclear. This study aimed to investigate the impact of EGFR-TKIs on concurrent SSNs in patients with stage IV non–small cell lung cancer (NSCLC).Materials and Methods Patients who received an EGFR-TKI for at least 1 month for stage IV NSCLC and had concurrent SSN(s) that had existed for at least 3 months on chest computed tomography were included in this retrospective study. Size change of each nodule before and after EGFR-TKI therapies were evaluated using a cutoff value of 2 mm; increase (≥ 2 mm), decrease (≤ –2 mm), and no change (–2 mm < size change < +2 mm).Results A total of 77 SSNs, 51 pure ground-glass (66.2%) and 26 part-solid nodules (33.8%), were identified in 59 patients who received gefitinib (n=45) and erlotinib (n=14). Among 58 EGFR mutation analysis performed for primary lung cancer, 45 (77.6%) were EGFR mutant. The proportions of decrease group were 19.5% (15/77) on per-nodule basis and 25.4% (15/59) on per-patient basis. Four SSNs (5.2%) disappeared completely. On per-patient based multivariable analysis, EGFR exon 19 deletion positivity for primary lung cancer was associated with a decrease after initial EGFR-TKI therapy (adjusted odds ratio, 4.29; 95% confidence interval, 1.21 to 15.29; p=0.025).Conclusion Approximately 20% of the concurrent SSNs decreased after the initial EGFR-TKI therapy. EGFR exon 19 deletion positivity for primary lung cancer was significantly associated with the size change of concurrent SSNs.

The novel compound GCJ-490A has been discovered as a pan-histone deacetylase (HDAC) inhibitor that exerts potent inhibitory activity against HDAC1, HDAC3, and HDAC6. Because of the important roles of HDACs in lung cancer development and the high distribution of GCJ-490A in lung tissue, we explored the anti-tumor potency of GCJ-490A against non-small cell lung cancer (NSCLC)TheGCJ-490A effectively inhibited NSCLC cell proliferation and induced apoptosisThese findings highlight the promising potential of HDAC inhibitors in NSCLC treatment and provide a rational basis for the application of HDAC inhibitors in combination with EGFR inhibitors in clinical trials.

In EGFR-mutant lung cancer, drug-tolerant persister cells (DTPCs) show prolonged survival when receiving EGFR tyrosine kinase inhibitor (TKI) treatments. They are a likely source of drug resistance, but little is known about how these cells tolerate drugs. Ribonucleic acids (RNAs) molecules control cell growth and stress responses. Nucleic acid metabolism provides metabolites, such as purines, supporting RNA synthesis and downstream functions. Recently, noncoding RNAs (ncRNAs), such as microRNAs (miRNAs), have received attention due to their capacity to repress gene expression via inhibitory binding to downstream messenger RNAs (mRNAs). Here, our study links miRNA expression to purine metabolism and drug tolerance. MiR-21-5p (guide strand) is a commonly upregulated miRNA in disease states, including cancer and drug resistance. However, the expression and function of miR-21-3p (passenger strand) are not well understood. We found that upregulation of miR-21-5p and miR-21-3p tune purine metabolism leading to increased drug tolerance. Metabolomics data demonstrated that purine metabolism was the top pathway in the DTPCs compared with the parental cells. The changes in purine metabolites in the DTPCs were partially rescued by targeting miR-21. Analysis of protein levels in the DTPCs showed that reduced expression of adenylosuccinate lyase (ADSL) was reversed after the miR-21 knockdown. ADSL is an essential enzyme in the de novo purine biosynthesis pathway by converting succino-5-aminoimidazole-4-carboxamide riboside (succino-AICAR or SAICAR) to AICAR (or acadesine) as well as adenylosuccinate to adenosine monophosphate (AMP). In the DTPCs, miR-21-5p and miR-21-3p repress ADSL expression. The levels of top decreased metabolite in the DTPCs, AICAR was reversed when miR-21 was blocked. AICAR induced oxidative stress, evidenced by increased reactive oxygen species (ROS) and reduced expression of nuclear factor erythroid-2-related factor 2 (NRF2). Concurrently, miR-21 knockdown induced ROS generation. Therapeutically, a combination of AICAR and osimertinib increased ROS levels and decreased osimertinib-induced NRF2 expression. In a MIR21 knockout mouse model, MIR21 loss-of-function led to increased purine metabolites but reduced ROS scavenging capacity in lung tissues in physiological conditions. Our data has established a link between ncRNAs, purine metabolism, and the redox imbalance pathway. This discovery will increase knowledge of the complexity of the regulatory RNA network and potentially enable novel therapeutic options for drug-resistant patients.

High-grade neuroendocrine tumors (NETs) of the lung consist of small-cell lung cancer (SCLC) and large-cell neuroendocrine carcinoma (LCNEC). Both exhibit aggressive malignancy with poor prognosis. The transformation of lung adenocarcinoma (ADC) to SCLC or LCNEC also contributes to acquired resistance to epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs). Despite initially being responsive to chemotherapy, high-grade NET patients inevitably develop drug resistance; thus, novel therapeutic targets are urgently needed for these patients. Our study reported that VGF (nerve growth factor inducible), a factor mainly expressed in neurons during neural development, is highly expressed in SCLC and LCNEC as well as in a subset of ADCs, whereas targeting VGF attenuates cancer cell growth and tumor formation. High VGF expression was associated with advanced stage SCLC and predicted poor prognosis in lung ADC. In addition, EGFR-TKI selection enriched VGF expression in TKI-resistant ADC under epigenetic control. The VGF locus possessed the HDAC1 binding site, and treatment of ADC cells with the HDAC1 inhibitor induced VGF expression. High VGF expression was associated with chemoresistance, and silencing VGF induced BMF and BCL2L11 expression and rendered lung cancer cells sensitive to chemotherapy drugs. These findings suggested the potential of VGF as a prognostic factor and therapeutic target in lung cancers with neuroendocrine feature.