Receptor Tyrosine Kinase Inhibitor Research Articles

Abstract 4035: Lipid-based nanoparticle combination immunotherapy with sitravatinib for the systemic treatment of high-risk neuroblastoma

Abstract We seek to develop a systemic, innate immunomodulatory nanoparticle therapy that combines synergistically with sitravatinib for the treatment of high-risk neuroblastoma, where metastasis is the largest hurdle for current treatment modalities. Here, we utilize a unique lipid-based nanoparticle (LNP) system comprised of co-encapsulated agonists of the Stimulator of Interferon Genes (STING) and Toll-like Receptor 4 (TLR4) pathways (immuno-NPs) that can be safely administered in the systemic blood circulation for delivery to the tumor microenvironment (TME) and uptake by perivascular innate antigen-presenting cells (APCs). STING/TLR4 agonists together promote the synergistic production of Type I interferon β (IFNβ), a key activator of anti-tumor immunity from the TME itself. Here, we also focus on sitravatinib, an investigational drug shown to inhibit receptor tyrosine kinases such as discoidin domain receptor 2 (DDR2), which can inhibit the sustained remodeling of collagen around primary tumors. The inhibition of such is vital to treatment as sustained collagen remodeling can facilitate the metastasis of cancer cells via epithelial-mesenchymal transition (EMT). We hypothesize that the downstream effects of sitravatinib treatment will augment tumor clearance and increase the therapeutic efficacy of immuno-NPs with respect to recruiting APCs. Our early pilot studies in humanized mice bearing orthotopic SH-5YSY tumors show that immuno-NPs are effective at tumor clearance. We found that mice inoculated subcutaneously with syngeneic 9464D-GD2 tumors showed decreased tumor growth when treated with our novel combination therapy in comparison to monotherapy controls. In both humanized and syngeneic tumor models, our ongoing mechanistic studies involve quantification of EMT in primary tumors, systemic nanoparticle deposition at metastatic sites, and the mechanistic impact of combination therapy on IFNβ-promoted elimination of metastasis. Here, we have proposed and tested an immunotherapy with great promise for treating neuroblastoma. However, the impact of nanoparticle-based immunotherapy reaches far beyond neuroblastoma: it has the potential to be a platform for the development of immunotherapies specific to other highly metastatic cancer types. Citation Format: Miranda Diaz-Infante, Griffin Kane, Christina Lusi, Meghan Brassil, Kim Wigglesworth, Christian Alarcon, Jason Shohet, Prabhani Atukorale. Lipid-based nanoparticle combination immunotherapy with sitravatinib for the systemic treatment of high-risk neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4035.

Abstract 1786: Metabolic rewiring induced by protein or calorie restriction provides unique therapeutic vulnerabilities in translocation and select clear cell renal cell carcinomas

Abstract While the approval of several combinations with immune checkpoint inhibitors have significantly improved the outcome of kidney cancer patients, advanced clear cell and non-clear cell renal cell carcinoma (RCC) remain a clinical challenge. There has been a longstanding interest in using dysregulated metabolism as a therapeutic target due to its association with the pathogenesis and progression of several cancer types. As one of these highly metabolic tumors, RCC has the potential to greatly benefit from strategies targeting tumor metabolism. Dietary interventions are an innovative adjunct therapy that has the potential to induce a wide range of anti-cancer effects by disrupting metabolism due to the role diet plays in providing tumors with macromolecules for energy metabolism. Unfortunately, tumor cell plasticity, intratumor heterogeneity, and a lack of understanding regarding metabolic vulnerabilities in tumors limit the efficacy of implementing these strategies and a fundamental gap in the field remains as to how basic metabolic requirements of the tumor can be targeted with specific dietary interventions. In this study, the inherent metabolic phenotypes of translocation RCC (tRCC) and clear cell RCC (ccRCC) were characterized by integrating in vivo metabolomics and transcriptomics data, assessing mitochondrial and glycolytic activity in vitro via Seahorse, and performing immunohistochemical analyses of patient samples. Interestingly, the respective mitochondrial and glycolytic dependencies in tRCC and ccRCC patient-derived xenograft (PDX) models appear to influence the response to nutrient deprivation as seen by in vitro assays conducted after amino acid or glucose restriction. Importantly, these results indicate that dietary interventions may be able to selectively target metabolic vulnerabilities in tRCC and ccRCC. Ongoing combination studies with either protein or calorie restriction and targeted therapies, such as standard of care receptor tyrosine-kinase inhibitors, suggest the benefit of using dietary interventions as an adjunct therapy in RCC. Overall, these studies reveal that selective dietary interventions alter the metabolic landscape of RCC and expose vulnerabilities that can be exploited with targeted therapy. As dietary interventions are a safe, affordable, and potentially well tolerated adjunct therapy, we anticipate that the results of these studies will provide the biologic and mechanistic support for translating this strategy to advanced RCC patients. Citation Format: Sabrina A. Orsi, Christopher Rupert, Sean Colligan, Musea Chang, Abbas Jawadwala, Ilaria Delle Fontane, Filomena de Nigris, Roberto Pili. Metabolic rewiring induced by protein or calorie restriction provides unique therapeutic vulnerabilities in translocation and select clear cell renal cell carcinomas [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1786.

L-Methionine accentuates anti-tumor action of Gefitinib in Gefitinib-resistant lung adenocarcinoma: Role of EGFR/ERK/AKT signaling and histone H3K36me2 alteration

Adenocarcinoma, the predominant subtype of non-small cell lung cancer (NSCLC), poses a significant clinical challenge due to its prevalence and aggressive nature. Gefitinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor is often susceptible to development of resistance despite being the preferred treatment option for NSCLC. In this study, we investigated the potential of L-Methionine in enhancing the cytotoxicity of Gefitinib and preventing resistance development. In vitro experiment employing the H1975 cell line demonstrated a notable enhancement in cytotoxic efficacy when L-Methionine (10 mM) was combined with Gefitinib, as indicated by a substantial reduction in IC50 values (155.854 ± 1.87 μM vs 45.83 ± 4.83 μM). Complementary in vivo investigations in a lung cancer model corroborated these findings. Co-administration of L-Methionine (100 mg/kg and 400 mg/kg) with Gefitinib (15 mg/kg) for 21 days exhibited marked improvements in therapeutic efficacy, which was observed by macroscopic and histopathological assessments. Mechanistic insights revealed that the enhanced cytotoxicity of the combination stemmed from the inhibition of the EGFR, modulating the downstream cascade of ERK/AKT and AMPK pathways. Concurrently inhibition of p-AMPK-α by the combination also disrupted metabolic homeostasis, leading to the increased production of reactive oxygen species (ROS). Notably, L-Methionine, functioning as a methyl group donor, elevated the expression of H3K36me2 (an activation mark), while reducing the p-ERK activity. Our study provides the first evidence supporting L-Methionine supplementation as a novel strategy to enhance Gefitinib chemosensitivity against pulmonary adenocarcinoma.

Clinical characteristics and MRI based radiomics nomograms can predict iPFS and short-term efficacy of third-generation EGFR-TKI in EGFR-mutated lung adenocarcinoma with brain metastases

BackgroundPredicting short-term efficacy and intracranial progression-free survival (iPFS) in epidermal growth factor receptor gene mutated (EGFR-mutated) lung adenocarcinoma patients with brain metastases who receive third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) therapy was of great significance for individualized treatment. We aimed to construct and validate nomograms based on clinical characteristics and magnetic resonance imaging (MRI) radiomics for predicting short-term efficacy and intracranial progression free survival (iPFS) of third-generation EGFR-TKI in EGFR-mutated lung adenocarcinoma patients with brain metastases.MethodsOne hundred ninety-four EGFR-mutated lung adenocarcinoma patients with brain metastases who received third-generation EGFR-TKI treatment were included in this study from January 1, 2017 to March 1, 2023. Patients were randomly divided into training cohort and validation cohort in a ratio of 5:3. Radiomics features extracted from brain MRI were screened by least absolute shrinkage and selection operator (LASSO) regression. Logistic regression analysis and Cox proportional hazards regression analysis were used to screen clinical risk factors. Single clinical (C), single radiomics (R), and combined (C + R) nomograms were constructed in short-term efficacy predicting model and iPFS predicting model, respectively. Prediction effectiveness of nomograms were evaluated by calibration curves, Harrell’s concordance index (C-index), receiver operating characteristic (ROC) curves and decision curve analysis (DCA). Kaplan-Meier analysis was used to compare the iPFS of high and low iPFS rad-score patients in the predictive iPFS R model and to compare the iPFS of high-risk and low-risk patients in the predictive iPFS C + R model.ResultsOverall response rate (ORR) was 71.1%, disease control rate (DCR) was 91.8% and median iPFS was 12.67 months (7.88–20.26, interquartile range [IQR]). There were significant differences in iPFS between patients with high and low iPFS rad-scores, as well as between high-risk and low-risk patients. In short-term efficacy model, the C-indexes of C + R nomograms in training cohort and validation cohort were 0.867 (0.835-0.900, 95%CI) and 0.803 (0.753–0.854, 95%CI), while in iPFS model, the C-indexes were 0.901 (0.874–0.929, 95%CI) and 0.753 (0.713–0.793, 95%CI).ConclusionsThe third-generation EGFR-TKI showed significant efficacy in EGFR-mutated lung adenocarcinoma patients with brain metastases, and the combined line plot of C + R can be utilized to predict short-term efficacy and iPFS.

Synergy of de-walled Ganoderma Lucidum spore powder (GLSP) on targeted therapy in advanced non-squamous non-small cell lung cancer with epidermal growth factor receptor (EGFR) mutant: protocol for a randomized, double-blind, placebo-controlled study

BackgroundOsimertinib is regarded as a promising third-generation epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) for advanced non-squamous non-small cell lung cancer (NSCLC) patients who developed T790M. However the adverse effects, primarily fatigue, remain an overwhelming deficiency of Osimertinib, hindering it from achieving adequate clinical efficacy for such NSCLC. Ganoderma lucidum has been used for thousands of years in China to combat fatigue, while Ganoderma Lucidum spores powder (GLSP) is the main active ingredient. The aim of this study is to investigate whether GLSP is sufficiently effective and safe in improving fatigue and synergizing with Osimertinib in non-squamous NSCLC patients with EGFR mutant.Method/designA total of 140 participants will be randomly assigned to receive either de-walled GSLP or placebo for a duration of 56 days. The primary outcome measure is the fatigue score associated with EGFR-TKI adverse reactions at week 8, evaluated by the Chinese version of the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire for Cancer Patients (QLQ-C30). Secondary outcomes include evaluation of treatment effectiveness, assessment of quality of life (QoL), and exploration of immune indicators and gut microbiota relationships. Following enrollment, visits are scheduled biweekly until week 12.Trial registrationChina Clinical Trial Registry ChiCTR2300072786. Registrated on June 25, 2023.

Investigating the Efficacy of EGFR-TKIs and Anti-VEGFR Combination in Advanced Non-Small Cell Lung Cancer: A Meta-Analysis.

The epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in combination with anti-vascular endothelial growth factor receptor (VEGFR) agents have shown improved survival outcomes in recent studies. However, its efficacy related to survival outcomes as a first- or second-line agent and based on generations remains to be explored. This study estimated the survival outcomes of EGFR-TKIs plus anti-VEGFR in combination in defined populations of advanced non-small cell lung cancer (NSCLC) patients overall, as a first- or second line of treatment, with different generations of EGFR-TKIs and EGFR-TKIs plus bevacizumab combination as a subgroup. A literature search was conducted using PubMed, SCOPUS, Cochrane Library, and ClinicalTrials.gov databases through June 2023 to identify primary research reporting the survival outcomes of EGFR-TKIs in combination with anti-VEGFR agents in patients with advanced NSCLC. Studies that were single-arm, published in non-English languages, and had missing data on survival outcomes were excluded. A meta-analysis was conducted to generate pooled hazard ratios (HRs) with 95% confidence intervals (CI) for overall survival (OS) and progression-free survival (PFS). Methodological quality and risk of bias in studies were assessed using the Cochrane Handbook for Systematic Reviews of Interventions risk of bias tool. A total of 20 randomized controlled trials were included in the qualitative synthesis, and 11 (2182 participants) were included in the meta-analysis. Patients' median age ranged from 58 to 68 years; 36% to 70% of patients were female; most of them had IIIa/b to IV stage cancer. In meta-analyses, the EGFR-TKIs plus anti-VEGFR combination resulted in improved PFS (HR, 0.73; 95% CI: 0.61, 0.86; p < 0.00001) in patients with advanced NSCLC but had no impact on OS (HR, 0.93; 95% CI: 0.79, 1.10; p = 0.41). The first line of treatment and first-generation EGFR-TKIs with the combination also improved the PFS (HR, 0.64; 95% CI: 0.57, 0.71; p < 0.00001; HR, 0.63; 95% CI: 0.56, 0.71; p < 0.00001) respectively, however, had no impact on OS. Our meta-analysis indicated EGFR-TKIs with anti-VEGFR in combination not only improved overall PFS but also showed similar results to a first line and first-generation agent compared to EGFR-TKI alone.

An epidermal growth factor receptor compound mutation of L858R with S768I in advanced non-small-cell lung cancer: a case report

BackgroundIn the current treatment landscape for non-small cell lung cancers, epidermal growth factor receptor-tyrosine kinase inhibitors have emerged as a well-established treatment option for patients with advanced or metastatic disease. This is particularly true for those with commonly occurring epidermal growth factor receptor mutations. However, the therapeutic efficacy of these agents for so-called rare epidermal growth factor receptor mutations, and in particular those characterized by a high degree of complexity, such as double mutations, remains a subject of clinical uncertainty.Case presentationIn this context, we present the case of a 64-year-old man of Moroccan descent, a lifelong non-smoker, diagnosed with metastatic non-small cell lung cancer characterized by a complex epidermal growth factor receptor mutation encompassing L858R and S768I. The patient subsequently underwent afatinib-based treatment, showing notable clinical results. These included a remarkable overall survival of 51 months, with a median progression-free survival of more than 39 months.ConclusionsThis case report is a compelling testimony to the evolving therapeutic landscape of non-small cell lung cancers, providing valuable insight into the potential therapeutic efficacy of epidermal growth factor receptor-tyrosine kinase inhibitors in the realm of rare and complex epidermal growth factor receptor mutations.

Synthesis of Bis-thiazoles Tethered 1,4-Dihydropyridine and Pyridine Linkers via Simple Oxidation and their Molecular Docking as VEGFR -TK Inhibitors.

In this study, a neoteric and expedient oxidation method is applied for a variety of Hantzsch 1,4-dihydropyridine derivatives such as 1,4-dihydro- 2,6-dimethyl-3,5-diacetylpyridine, 3,5-bis-hydrazono--2,6-dimethyl-1,4-dihydropyridine, and 3,5-bis-thiazoly-2,6-dimethyl-1,4-dihydro pyridine. This simple oxidation is based upon the in situ generation of nitrous acid from an aqueous sodium nitrite and acetic acid mixture and could be used to downgrade costs, sustain resources, and minimize chemical wastes. Also, a molecular modeling strategy was used to study the mechanism of action for various derivatives of bis-hydrazinylidene- thiazole as the protein Vascular Endothelial Growth Factor Receptor Tyrosine Kinase (VEGFR TK) inhibitor through evaluating their binding scores and modes compared with Sorafenib as a reference standard. The results revealed that the interaction of hydrazinylidene and thiazole as an anticancer Tyrosine Kinase inhibitor has been improved. Additionally, the compounds exhibiting the highest activity were assessed for their potential anticancer effects against HepG-2, MCF-7, and WI-38 cells, and the outcomes demonstrated encouraging activity against cancer.

Clinical phase II trial shows that combining osimertinib and afatinib resistance EGFR recurrent mutation in EGFR-mutant lung cancer

Treatment options for patients with non-small-cell lung cancer (NSCLC) with EGFR mutations are limited due to resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs). Osimertinib or afatinib alone, in a preclinical model, created drug-resistant clones with EGFR secondary mutations, but their combination inhibited the emergence of these mutations. In a Phase II trial, we looked into the alternating-dose therapy of osimertinib and afatinib in patients with EGFR-mutant NSCLC. Patients with stage IV NSCLC with an activating EGFR mutation who had never received treatment were included. Every eight weeks, osimertinib (80 mg/day) and afatinib (20 mg/day) were given in alternate cycles. Utilising circulating tumour DNA collected both before and after therapy, genomic analysis was carried out. The median progression-free survival among the 50 enrolled patients was 21.3 months. A total of 70.3% of respondents responded. Overall median survival was not attained. 35 plasma samples were acquired after the development of resistance; 5 of these samples displayed an elevated MET gene copy number and 3 displayed a BRAF mutation. However, no secondary EGFR mutation was found. The effectiveness of our approach was comparable to that of osimertinib alone, as had been observed in untreated advanced NSCLC patients with EGFR mutations in the past. The treatment may stop the emergence of EGFR secondary mutations that lead to medication resistance, despite the small sample size. To determine the importance of this treatment, more research is required.

Real-World Treatment Patterns and Survival Among Patients with Stage I-III, Non-Squamous, Non-Small Cell Lung Cancer Receiving Surgery as Primary Treatment.

Approximately half of patients with non-small cell lung cancer (NSCLC) present with early-stage disease at diagnosis. Real-world outcomes data are limited for this population but are of interest given recent and impending results from trials evaluating epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) and immunotherapies in neoadjuvant, adjuvant, and perioperative settings. A retrospective, longitudinal, population-level study was conducted in patients diagnosed with resected stage I-III non-squamous NSCLC in Ontario, Canada, between April 2010 and March 2019. Study outcomes included patient characteristics and median overall survival (mOS), with stratification by disease stage and treatment exposure. Patients receiving EGFR-TKIs (assumed EGFR mutation-positive by proxy) were a key population of interest. Among 8255 cases, 4881 had stage I, 2124 had stage II, and 1250 had stage III NSCLC at diagnosis. The mean patient age was 68years; 53.5% were female. In the overall cohort, 19.6% received adjuvant chemotherapy. Receipt of adjuvant chemotherapy was associated with significantly longer mOS than not receiving such therapy: stage II (7.6 [95% confidence interval: 6.5-8.5] vs. 4.4[4.0-4.9] years) or stage III (4.4 [3.6-5.1] vs. 2.7 [2.3-3.3] years), both p < 0.0001. Patients receiving treatment (EGFR-TKIs and chemotherapy) were assumed to have experienced disease recurrence/relapse; mOS was longer among those receiving an EGFR-TKI than among those receiving chemotherapy (2.3[1.8-3.0] vs. 1.1[1.0-1.3] years). In Ontario, between 2010 and 2019, uptake of adjuvant therapy was low among patients with resected NSCLC, despite such therapy being associated with improved survival. Patients assumed to have recurred/relapsed had markedly reduced mOS, regardless of subsequent therapy, compared with those who did not relapse/recur. Novel peri-adjuvant treatment options are needed to enhance outcomes after lung resection.

High-efficiency EGFR genotyping using cell-free DNA in bronchial washing fluid.

EGFR mutation testing is required for treatment of lung adenocarcinoma using epidermal growth factor receptor-tyrosine kinase inhibitor. However, the amounts of tumor tissue or tumor cells obtained by bronchoscopy are often insufficient. Bronchial washing fluid, obtained by lavage with saline after tumor biopsy or brushing, and the supernatant of bronchial washing fluid are thought to contain cell-free DNA that would be potentially applicable for EGFR testing. From among patients with suspected adenocarcinoma or non-small cell lung carcinoma diagnosed from biopsy or surgical specimens at the University of Tsukuba Hospital between 2015 and 2019, cell-free DNAs from 80 specimens of supernatant of bronchial washing fluid (50 with EGFR mutation and 30 with wild type EGFR) and 8 blood serum samples were examined for EGFR mutation using droplet digital PCR. Among the 50 patients harboring EGFR mutation, the rate of positivity for cell-free DNA extracted from supernatant of bronchial washing fluid was 80% (40/50). In nine of the EGFR mutation-positive cases, tumor cells were not detected by either biopsy or cytology, but the mutation was detected in four cases (4/9, 44%). Comparison of the cell-free DNA mutation detection rate between supernatant of bronchial washing fluid and blood serum in six cases showed that mutations were detected from the former in all cases (6/6, 100%), but from the latter in only one case (1/6, 17%). Using supernatant of bronchial washing fluid samples, the detection rate of EGFR mutation was high, and EGFR mutations were detectable even when no tumor cells had been detectable by biopsy or cytology. Supernatant of bronchial washing fluid might be an effective sample source for EGFR mutation testing.

NEAT1_1 confers gefitinib resistance in lung adenocarcinoma through promoting AKR1C1-mediated ferroptosis defence

Gefitinib is one of the most extensively utilized epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) for treating advanced lung adenocarcinoma (LUAD) patients harboring EGFR mutation. However, the emergence of drug resistance significantly compromised the clinical efficacy of EGFR-TKIs. Gaining further insights into the molecular mechanisms underlying gefitinib resistance holds promise for developing novel strategies to overcome the resistance and improve the prognosis in LUAD patients. Here, we identified that the inhibitory efficacy of gefitinib on EGFR-mutated LUAD cells was partially dependent on the induction of ferroptosis, and ferroptosis protection resulted in gefitinib resistance. Among the ferroptosis suppressors, aldo-keto reductase family 1 member C1 (AKR1C1) exhibited significant upregulation in gefitinib-resistant strains of LUAD cells and predicted poor progression-free survival (PFS) and overall survival (OS) of LUAD patients who received first-generation EGFR-TKI treatment. Knockdown of AKR1C1 partially reversed drug resistance by re-sensitizing the LUAD cells to gefitinib-mediated ferroptosis. The decreased expression of miR-338-3p contributed to the aberrant upregulation of AKR1C1 in gefitinib-resistant LUAD cells. Furthermore, upregulated long non-coding RNA (lncRNA) nuclear paraspeckle assembly transcript 1_1 (NEAT1_1) sponged miR-338-3p to neutralize its suppression on AKR1C1. Dual-luciferase reporter assay and miRNA rescue experiment confirmed the NEAT1_1/miR-338-3p/AKR1C1 axis in EGFR-mutated LUAD cells. Gain- and loss-of-function assays demonstrated that the NEAT1_1/miR-338-3p/AKR1C1 axis promoted gefitinib resistance, proliferation, migration, and invasion in LUAD cells. This study reveals the effects of NEAT1_1/miR-338-3p/AKR1C1 axis-mediated ferroptosis defence in gefitinib resistance in LUAD. Thus, targeting NEAT1_1/miR-338-3p/AKR1C1 axis might be a novel strategy for overcoming gefitinib resistance in LUAD harboring EGFR mutation.

Surgery of enlarging lesions after stereotactic radiosurgery for brain metastases in patients with non-small cell lung cancer with oncogenic driver mutations frequently reveals radiation necrosis: case series and review.

In brain metastases, radiation necrosis (RN) is a complication that arises after single or multiple fractionated stereotactic radiosurgery (SRS/FSRS), which is challenging to distinguish from local recurrence (LR). Studies have shown increased RN incidence rates in non-small cell lung cancer (NSCLC) patients with oncogenic driver mutations (ODMs) or receiving tyrosine kinase inhibitors (TKIs). This study investigated enlarging brain lesions following SRS/FSRS, for which additional surgeries were performed to distinguish between RN and LR. We investigated seven NSCLC patients with ODMs undergoing SRS/FSRS for BM and undergoing surgery for suspicion of LR on MRI imaging. Descriptive statistics were performed. Among the seven patients, six were EGFR+, while one was ALK+. The median irradiation dose was 30 Gy (range, 20-35 Gy). The median time to develop RN after SRS/FSRS was 11.1 months (range: 6.3-31.2 months). Moreover, gradually enlarging lesions were found in all patients after 6 months post-SRS/FSR. Brain radiation necrosis was pathologically confirmed in all the patients. RN should be suspected in NSCLC patients when lesions keep enlarging after 6 months post-SRS/FSRS, especially for patients with ODMs and receiving TKIs. Further, this case series indicates that further dose reduction might be necessary to avoid RN for such patients.

Tet methylcytosine dioxygenase 2 (TET2) deficiency elicits EGFR-TKI (tyrosine kinase inhibitors) resistance in non-small cell lung cancer

Despite epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) have shown remarkable efficacy in patients with EGFR-mutant non-small cell lung cancer (NSCLC), acquired resistance inevitably develops, limiting clinical efficacy. We found that TET2 was poly-ubiquitinated by E3 ligase CUL7FBXW11 and degraded in EGFR-TKI resistant NSCLC cells. Genetic perturbation of TET2 rendered parental cells more tolerant to TKI treatment. TET2 was stabilized by MEK1 phosphorylation at Ser 1107, while MEK1 inactivation promoted its proteasome degradation by enhancing the recruitment of CUL7FBXW11. Loss of TET2 resulted in the upregulation of TNF/NF-κB signaling that confers the EGFR-TKI resistance. Genetic or pharmacological inhibition of NF-κB attenuate the TKI resistance both in vitro and in vivo. Our findings exemplified how a cell growth controlling kinase MEK1 leveraged the epigenetic homeostasis by regulating TET2, and demonstrated an alternative path of non-mutational acquired EGFR-TKI resistance modulated by TET2 deficiency. Therefore, combined strategy exploiting EGFR-TKI and inhibitors of TET2/NF-κB axis holds therapeutic potential for treating NSCLC patients who suffered from this resistance.

Treatment outcomes and prognostic factors in patients with driver mutant non-small cell lung cancer and de novo brain metastases

Central nervous system (CNS) metastases can be seen at a rate of 30% in advanced stages for patients with non-small cell lung cancer (NSCLC). Growing evidence indicates the predictive roles of driver gene mutations in the development of brain metastases (BM) in recent years, meaning that oncogene-driven NSCLC have a high incidence of BM at diagnosis. Today, 3rd generation targeted drugs with high intracranial efficacy, which can cross the blood–brain barrier, have made a positive contribution to survival for these patients with an increased propensity to BM. It is important to update the clinical and pathological factors reflected in the survival with real-life data. A multi-center, retrospective database of 306 patients diagnosed with driver mutant NSCLC and initially presented with BM between between November 2008 and September 2022 were analyzed. The median progression-free survival (mPFS) was 12.25 months (95% CI, 10–14.5). While 254 of the patients received tyrosine kinase inhibitor (TKI), 51 patients received chemotherapy as first line treatment. The median intracranial PFS (iPFS) was 18.5 months (95% CI, 14.8–22.2). The median overall survival (OS) was 29 months (95% CI, 25.2–33.0). It was found that having 3 or less BM and absence of extracranial metastases were significantly associated with better mOS and iPFS. The relationship between the size of BM and survival was found to be non-significant. Among patients with advanced NSCLC with de novo BM carrying a driver mutation, long-term progression-free and overall survival can be achieved with the advent of targeted agents with high CNS efficacy with more conservative and localized radiotherapy modalities.

FHND004 inhibits malignant proliferation of multiple myeloma by targeting PDZ-binding kinase in MAPK pathway.

Inhibitors of Epidermal growth factor receptor tyrosine kinase (EGFR-TKIs) are producing impressive benefits to responsive types of cancers but challenged with drug resistances. FHND drugs are newly modified small molecule inhibitors based on the third-generation EGFR-TKI AZD9291 (Osimertinib) that are mainly for targeting the mutant-selective EGFR, particularly for the non-small cell lung cancer (NSCLC). Successful applications of EGFR-TKIs to other cancers are less certain, thus the present pre-clinical study aims to explore the anticancer effect and downstream targets of FHND in multiple myeloma (MM), which is an incurable hematological malignancy and reported to be insensitive to first/second generation EGFR-TKIs (Gefitinib/Afatinib). Cell-based assays revealed that FHND004 and FHND008 significantly inhibited MM cell proliferation and promoted apoptosis. The RNA-seq identified the involvement of the MAPK signaling pathway. The protein chip screened PDZ-binding kinase (PBK) as a potential drug target. The interaction between PBK and FHND004 was verified by molecular docking and microscale thermophoresis (MST) assay with site mutation (N124/D125). Moreover, the public clinical datasets showed high expression of PBK was associated with poor clinical outcomes. PBK overexpression evidently promoted the proliferation of two MM cell lines, whereas the FHND004 treatment significantly inhibited survival of 5TMM3VT cell-derived model mice and growth of patient-derived xenograft (PDX) tumors. The mechanistic study showed that FHND004 downregulated PBK expression, thus mediating ERK1/2 phosphorylation in the MAPK pathway. Our study not only demonstrates PBK as a promising novel target of FHND004 to inhibit MM cell proliferation, but also expands the EGFR kinase-independent direction for developing anti-myeloma therapy.

Antibody dependent cellular cytotoxicity-inducing anti-EGFR antibodies as effective therapeutic option for cutaneous melanoma resistant to BRAF inhibitors.

About 50% of cutaneous melanoma (CM) patients present activating BRAF mutations that can be effectively targeted by BRAF inhibitors (BRAFi). However, 20% of CM patients exhibit intrinsic drug resistance to BRAFi, while most of the others develop adaptive resistance over time. The mechanisms involved in BRAFi resistance are disparate and globally seem to rewire the cellular signaling profile by up-regulating different receptor tyrosine kinases (RTKs), such as the epidermal growth factor receptor (EGFR). RTKs inhibitors have not clearly demonstrated anti-tumor activity in BRAFi resistant models. To overcome this issue, we wondered whether the shared up-regulated RTK phenotype associated with BRAFi resistance could be exploited by using immune weapons as the antibody-dependent cell cytotoxicity (ADCC)-mediated effect of anti-RTKs antibodies, and kill tumor cells independently from the mechanistic roots. By using an in vitro model of BRAFi resistance, we detected increased membrane expression of EGFR, both at mRNA and protein level in 4 out of 9 BRAFi-resistant (VR) CM cultures as compared to their parental sensitive cells. Increased EGFR phosphorylation and AKT activation were observed in the VR CM cultures. EGFR signaling appeared dispensable for maintaining resistance, since small molecule-, antibody- and CRISPR-targeting of EGFR did not restore sensitivity of VR cells to BRAFi. Importantly, immune-targeting of EGFR by the anti-EGFR antibody cetuximab efficiently and specifically killed EGFR-expressing VR CM cells, both in vitro and in humanized mouse models in vivo, triggering ADCC by healthy donors' and patients' peripheral blood cells. Our data demonstrate the efficacy of immune targeting of RTKs expressed by CM relapsing on BRAFi, providing the proof-of-concept supporting the assessment of anti-RTK antibodies in combination therapies in this setting. This strategy might be expected to concomitantly trigger the crosstalk of adaptive immune response leading to a complementing T cell immune rejection of tumors.

Brigatinib, a newly discovered AXL inhibitor, suppresses AXL-mediated acquired resistance to osimertinib in EGFR-mutated non-small cell lung cancer.

In addition to the classical resistance mechanisms, receptor tyrosine-protein kinase AXL is a main mechanism of resistance to third-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) osimertinib in EGFR-mutated non-small cell lung cancer (NSCLC). Developing an effective AXL inhibitor is important to sensitize osimertinib in clinical application. In this study we assessed the efficacy of brigatinib, a second-generation of anaplastic lymphoma kinase (ALK)-TKI, as a novel AXL inhibitor, in overcoming acquired resistance to osimertinib induced by AXL activation. We established an AXL-overexpression NSCLC cell line and conducted high-throughput screening of a small molecule chemical library containing 510 anti-tumor drugs. We found that brigatinib potently inhibited AXL expression, and that brigatinib (0.5 μM) significantly enhanced the anti-tumor efficacy ofosimertinib (1 μM) in AXL-mediated osimertinib-resistant NSCLC cell lines in vitro. We demonstrated that brigatinib had a potential ability to bind AXL kinase protein and further inhibit its downstream pathways in NSCLC cell lines. Furthermore, we revealed that brigatinib might decrease AXL expression through increasing K48-linked ubiquitination of AXL and promoting AXL degradation in HCC827OR cells and PC-9OR cells. In AXL-high expression osimertinib-resistant PC-9OR and HCC827OR cells derived xenograft mouse models, administration of osimertinib (10 mg·kg-1·d-1) alone for 3 weeks had no effect, and administration of brigatinib (25 mg·kg-1·d-1) alone caused a minor inhibition on the tumor growth; whereas combination of osimertinib and brigatinib caused marked tumor shrinkages. We concluded that brigatinib may be a promising clinical strategy for enhancing osimertinib efficacy in AXL-mediated osimertinib-resistant NSCLC patients.

Prognostic impact of clinical and radiological factors on leptomeningeal metastasis from solid cancers.

The number of leptomeningeal metastasis (LM) patients has increased in recent years, as the cancer survival rates increased. An optimal prediction of prognosis is essential for selecting an appropriate treatment. The European Association of Neuro-Oncology-European Society for Medical Oncology (EANO-ESMO) guidelines for LM proposed a classification based on the cerebrospinal fluid cytological findings and contrast-enhanced magnetic resonance imaging (MRI) pattern. However, few studies have validated the utility of this classification. This study aimed to investigate the prognostic factors of LM, including the radiological and cytological types. We retrospectively analyzed the data of 240 adult patients with suspected LM who had undergone lumbar puncture between April 2014 and September 2021. The most common primary cancer types were non-small-cell lung cancer (NSCLC) (143 (60%)) and breast cancer (27 (11%)). Positive cytology results and the presence of leptomeningeal lesions on contrast-enhanced MRI correlated with decreased survival in all patients. Nodular lesions detected on contrast-enhanced magnetic resonance were a poor prognostic factor in cytology-negative patients, while contrast-enhanced patterns had no prognostic significance in cytology-positive patients. Systemic therapy using cytotoxic agents and molecular-targeted therapy after LM diagnosis correlated with prolonged survival, regardless of the cytology results. Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor treatment and systemic chemotherapy after LM improved the survival of EGFR-mutated and wild-type NSCLC patients with positive cytology results. This study validated the efficacy of prognostication according to the EANO-ESMO guidelines for LM. Systemic therapy after LM diagnosis improves the survival of NSCLC patients.

Genomic testing and targeted therapy of non-small cell lung cancer in China: a nationwide survey of physicians and clinical pathologists.

Genomic diagnostic testing is necessary to guide optimal treatment for non-small cell lung cancer (NSCLC) patients. The proportion of NSCLC patients whose treatment was selected based on genomic testing is still unknown in many countries or needs further improvement. This survey aimed to assess perception of genomic testing and targeted therapy for NSCLC in clinical pathologists and physicians across China. The web-based survey was conducted with 150 clinical pathologists and 450 physicians from oncology, respiratory and thoracic surgery departments from May to September 2020, across 135 cities in China. The participants had >5 years of clinical experience in genomic testing, diagnosis or treatment of NSCLC. Clinical pathologists reported capability of epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), and ROS proto-oncogene 1 (ROS-1) testing as 95.3%, 94.7%, and 84.7%, respectively, but only 81.9%, 75.5%, and 65.6% of physicians believed that the pathology department of the hospital is capable of performing the testing. The proportions of sending out specimens for testing were 21.0% and 49.7% as reported from clinical pathologists and physicians, respectively. Testing for EGFR mutation was recommended by physicians most often, followed by ALK and ROS-1 rearrangement. As first-line treatment, among the newly diagnosed patients with EGFR mutation, 77% received tyrosine kinase inhibitors (TKIs) therapy (49% treated with gefitinib); among patients with ALK rearrangement, 71% received TKI (64% treated with crizotinib); among patients with ROS-1 fusion, 65% received TKI (88% treated with crizotinib). The improvement of the non-tertiary hospital pathology departments' detection capabilities and the physicians' awareness are needed for enhancing the rate of genomic testing and targeted therapy in NSCLC patients in China.