A Rapid One-Pot Workflow for Sensitive Microscale Phosphoproteomics.

Compared to advancements in single-cell proteomics, phosphoproteomics sensitivity has lagged behind due to low abundance, complex sample preparation, and substantial sample input requirements. We present a simple and rapid one-pot phosphoproteomics workflow (SOP-Phos) integrated with data-independent acquisition mass spectrometry (DIA-MS) for microscale phosphoproteomic analysis. SOP-Phos adapts sodium deoxycholate based one-step lysis, reduction/alkylation, direct trypsinization, and phosphopeptide enrichment by TiO2 beads in a single-tube format. By reducing surface adsorptive losses via utilizing n-dodecyl ß-d-maltoside precoated tubes and shortening the digestion time, SOP-Phos is completed within 3-4 h with a 1.4-fold higher identification coverage. SOP-Phos coupled with DIA demonstrated >90% specificity, enhanced sensitivity, lower missing values (<1%), and improved reproducibility (8%-10% CV). With a sample size-comparable spectral library, SOP-Phos-DIA identified 33,787 ± 670 to 22,070 ± 861 phosphopeptides from 5 to 0.5 µg cell lysate and 30,433 ± 284 to 6,548 ± 21 phosphopeptides from 50,000 to 2,500 cells. Such sensitivity enabled mapping key lung cancer signaling sites, such as EGFR autophosphorylation sites Y1197/Y1172 and drug targets. The feasibility of SOP-Phos-DIA was demonstrated on EGFR-TKI sensitive and resistant cells, revealing the interplay of multipathway Hippo-EGFR-ERBB signaling cascades underlying the mechanistic insight into EGFR-TKI resistance. Overall, SOP-Phos-DIA is an efficient and robust protocol that can be easily adapted in the community for microscale phosphoproteomic analysis.

Outcomes in non-small cell lung cancer with uncommon epidermal growth factor receptor L858 substitutions under first-line epidermal growth factor receptor tyrosine kinase inhibitors: A large real-world cohort study.

Atypical L858R or other L858X mutations in the epidermal growth factor receptor (EGFR) gene, beyond the classical EGFRL858R mutation caused by c.2573 T > G, have been identified in non-small cell lung cancer (NSCLC), yet their genomic features and survival benefits with EGFR tyrosine kinase inhibitor (TKI) treatment have not been fully explored. We retrospectively enrolled 489 NSCLC patients with baseline tumor tissue/plasma samples carrying uncommon EGFRL858R (N = 124), EGFRL858Q/M (N = 17), or classical EGFRL858R mutations (N = 348). The comparison of molecular features was performed using treatment-naïve tumor tissues. Survival benefits and resistance mechanisms of first-line EGFR TKI treatment were studied in an advanced disease subcohort. NSCLCs harboring uncommon EGFRL858R had lower TP53 mutation prevalence (p = 0.04) and chromosome instability scores (p = 0.02) than those with classical EGFRL858R. Concomitant EGFRL861Q mutations were enriched in NSCLCs with EGFRL858Q/M (p < 0.01), with cooccurrence in those carrying EGFRL858M. Patients with uncommon EGFRL858R experienced improved progression-free survival (PFS) compared to those with classical EGFRL858R (median: 13.0 vs. 10.0 months, hazard ratio [HR]: 0.57, 95% confidence interval [CI]: 0.41-0.80). The association remained significant when adjusting for sex, age, histological subtype, TKI category, and anti-vascular therapy (HR: 0.55, 95% CI: 0.39-0.77). Furthermore, EGFRL858Q/M patients showed enhanced first-line PFS (vs. classical EGFRL858R, HR: 0.26, 95% CI: 0.10-0.67), potentially benefiting more from afatinib. Additionally, NSCLCs with uncommon EGFRL858R and classical EGFRL858R had similar resistance profiles to EGFR TKIs. In conclusion, NSCLCs carrying atypical EGFR L858 aberrations, which had fewer TP53 mutations and higher chromosome stability, exhibited improved PFS under first-line EGFR TKIs than those with the classical EGFRL858R.

The effect of food on the pharmacokinetics of Sutetinib maleate capsule, an irreversible EGFR tyrosine kinase inhibitor, in healthy Chinese subjects.

Sutetinib is an irreversible inhibitor of epidermal growth factor receptor (EGFR) and showed favorable efficacy and safety in patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) harbouring nondrug-resistant rare EGFR mutations. To evaluate the potential food effect, eighteen healthy Chinese subjects were enrolled in a single-centre, randomized, open-label, two-sequence, two-period crossover study. Sutetinib was administered as a single oral 100 mg under fasting or fed conditions, and pharmacokinetic sampling was performed following each dose and analysed by a validated liquid chromatography/mass spectrometry method. Safety and tolerability were also evaluated. Food intake slightly decreased maximum plasma concentration (Cmax) and area under the plasma concentration-time curve from time 0 to infinity (AUC0 - inf) of sutetinib (geometric least-squares mean [GLSM] ratio, 80.94% and 86.11%; 90% confidence interval [CI], 68.43-95.72 and 75.88-97.73) and its active metabolite sutetinib N-Oxide (GLSM ratio, 75.58% and 84.00%; 90% CI, 65.69-86.95 and 75.42-93.56), respectively. In addition, the time to maximum plasma concentration (Tmax) of both sutetinib and its metabolite has been prolonged by 2 h under fed conditions. A total of 31 adverse events (AEs) occurred during the study, with no serious adverse events (SAE) reported, and no obvious difference was observed between the fasting and fed groups. Our results demonstrated that a high-fat and high-calorie diet caused a significant delay in drug absorption and a marginal reduction in drug exposure. Sutetinib was generally well tolerated in healthy Chinese subjects. (This trial was registered at http://www.chinadrugtrials.org.cn . The registration No. is CTR20201933, and the date of registration is 2020-10-16).

Oral lichenoid drug eruption due to osimertinib for lung cancer.

INTRODUCTION: Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR) are linked with side effects involving skin and mucosa. Herein, we present a unique case of oral lichenoid drug eruption (LDE) in a patient treated with osimertinib. CASE REPORT: A 75-year-old woman was diagnosed with metastatic EGFR-mutated lung adenocarcinoma, and started on osimertinib 80 mg PO daily. At 24 months of therapy, the patient developed a painful, red, and white striated oral lesion involving the left buccal mucosa and the adjacent buccal aspect of gingivae. Biopsy showed oral LDE. Causality assessment between osimertinib and the oral LDE via Naranjo Adverse Drug Reaction probability scale revealed a score of 5. MANAGEMENT AND OUTCOME: Osimetinib discontinuation was not felt to be in the best interest of the patient. Therefore, diphenhydramine HCL mouthwash every 6 h PRN (before meals) was started. Spicy and hot foods were discontinued. At a four-week follow-up visit, the patient reported moderate improvement in her symptoms. CONCLUSION: Oral LDEs are considered premalignant lesions as they can transform into squamous cell carcinoma; therefore, regular follow-up is needed. Awareness of this potential side effect of osimertinib would also prevent unnecessary (and potentially costly) work-up and lead to its prompt diagnosis and treatment.

The Impact of Inadequate Exposure to Epidermal Growth Factor Receptor-Tyrosine Kinase Inhibitors on the Development of Resistance in Non-Small-Cell Lung Cancer Cells.

Epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) patients treated with EGFR-tyrosine kinase inhibitors (TKIs) inevitably develop resistance through several biological mechanisms. However, little is known on the molecular mechanisms underlying acquired resistance to suboptimal EGFR-TKI doses, due to pharmacodynamics leading to inadequate drug exposure. To evaluate the effects of suboptimal EGFR-TKI exposure on resistance in NSCLC, we obtained HCC827 and PC9 cell lines resistant to suboptimal fixed and intermittent doses of gefitinib and compared them to cells exposed to higher doses of the drug. We analyzed the differences in terms of EGFR signaling activation and the expression of epithelial-mesenchymal transition (EMT) markers, whole transcriptomes byRNA sequencing, and cell motility. We observed that the exposure to low doses of gefitinib more frequently induced a partial EMT associated with an induced migratory ability, and an enhanced transcription of cancer stem cell markers, particularly in the HCC827 gefitinib-resistant cells. Finally, the HCC827 gefitinib-resistant cells showed increased secretion of the EMT inducer transforming growth factor (TGF)-ß1, whose inhibition was able to partially restore gefitinib sensitivity. These data provide evidence that different levels of exposure to EGFR-TKIs in tumor masses might promote different mechanisms of acquired resistance.

Design, synthesis and evaluation of new pyrimidine derivatives as EGFRC797S tyrosine kinase inhibitors.

The clinical use of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) in the treatment of non-small cell lung cancer was limited by the drug resistance caused by EGFRC797S mutation. Therefore, in order to overcome the drug resistance, we designed and synthesized a series of 2-aminopyrimidine derivatives as EGFRC797S-TKIs. Among these compounds, compounds A5 and A13 showed significant anti-proliferative activity against the KC-0116 (EGFRdel19/T790M/C797S) cell line with high selectivity. A5 inhibited EGFR phosphorylation and induced apoptosis of KC-0116 cell, arrested KC-0116 cell at G2/M phase. Molecular docking results showed that A5 and brigatinib bind to EGFR in a similar pattern. In addition to forming two important hydrogen bonds with Met793 residue, A5 also formed a hydrogen bond with Lys745 residues, which may play an important role for the potent inhibitory activity against EGFRdel19/T790M/C797S. Based on these results, A5 turned out to be effective reversible EGFRC797S-TKIs which can be further developed.

Repurposing the Kinase Inhibitor Mavelertinib for Giardiasis Therapy.

A phenotypic screen of the ReFRAME compound library was performed to identify cell-active inhibitors that could be developed as therapeutics for giardiasis. A primary screen against Giardia lamblia GS clone H7 identified 85 cell-active compounds at a hit rate of 0.72%. A cytotoxicity counterscreen against HEK293T cells was carried out to assess hit compound selectivity for further prioritization. Mavelertinib (PF-06747775), a third-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), was identified as a potential new therapeutic based on indication, activity, and availability after reconfirmation. Mavelertinib has in vitro efficacy against metronidazole-resistant 713-M3 strains. Other EGFR-TKIs screened in follow-up assays exhibited insignificant inhibition of G. lamblia at 5 µM, suggesting that the primary molecular target of mavelertinib may have a different mechanistic binding mode from human EGFR-tyrosine kinase. Mavelertinib, dosed as low as 5 mg/kg of body weight or as high as 50 mg/kg, was efficacious in the acute murine Giardia infection model. These results suggest that mavelertinib merits consideration for repurposing and advancement to giardiasis clinical trials while its analogues are further developed.

Gene alternation of cerebrospinal fluid in patients with leptomeningeal metastases of lung adenocarcinoma using next-generation sequencing.

BACKGROUND: Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) provide a better prognosis in EGFR-mutant non-small cell lung cancer (NSCLC). Nevertheless, the outcome of leptomeningeal metastasis (LM) remains poor. In addition, due to limited access to intracranial tumour tissue, gene alterations associated with leptomeningeal metastasis from lung adenocarcinoma (LM-LUAD) are unclear. METHODS: Forty-five patients with LM-LUAD from May 2019 to June 2021 in Guangdong Sanjiu Brain Hospital were enrolled in this study. Seventy-five percent (34/45) of patients with LM harbored EGFR mutations, and patients with progressive disease (PD) of LM had 3rd-generation EGFR-TKI therapy and were defined as Cohort 1; those without 3rd-generation EGFR-TKI therapy were defined as Cohort 2. Next-generation targeted panel sequencing (NGS) was performed in each cerebrospinal fluid (CSF) sample of the two cohorts, and 9/45 LM-LUAD patients had matched plasma (PLA). RESULTS: The common gene alterations discovered in the CSF of LM-LUAD were EGFR mutation (34/45, 75%), TP53 (25/45, 56%), CDKN2A (9/45, 20%), ALK (7/45, 16%), CTNNB1 (6/45, 13%), MET (5/45, 11%), APC (4/45, 9%), FGF4 (4/45, 9%), FGF3 (4/45, 9%), ERBB2 (4/45, 9%), and PIK3CG (4/45, 9%). Cooccurring mutations of TP53 and EGFR were found in 49% (22/45) of patients and correlated with poor prognosis. CDKN2A was identified in 20% (9/45) of patients and presented slightly shorter overall survival (OS) than those without (7.1 versus 8.8 months, p = 0.2). Cohort 1 had more genes associated with poor prognosis, consisting of CDK4, CDKN2A, PIK3CG, or PIK3CA, and YES1 and MET were more likely to be detected in cohort 2. The alteration of EGFR was comparable between CSF and matched PLA. Incidences of gene alterations such as CDK4, CDKN2A, MET, SOX2, JAK2, BRAF, and PIK3CG were more likely to be identified in CSF. All mutant allele frequencies (MAF) were much higher in CSF than in matched PLA. CONCLUSIONS: CSF could be a potential candidate for the genetic profiling of LM-LUAD, demonstrating the genetic characteristics of LM in EGFR-mutated lung adenocarcinoma on diverse EGFR-TKI therapies.

Liquid biopsy for detecting epidermal growth factor receptor mutation among patients with non-small cell lung cancer treated with afatinib: a multicenter prospective study.

BACKGROUND: This study aimed to determine the effectiveness of liquid biopsy in detecting epidermal growth factor receptor (EGFR) mutations at diagnosis, disease progression, and intermediate stages. METHODS: This prospective, multicenter, observational study included 30 patients with non-small cell lung cancer treated with afatinib, harboring a major EGFR mutation confirmed by tumor tissue biopsy. We collected blood samples for liquid biopsy at diagnosis, intermediate stage, and progressive disease. Tissue and liquid biopsies were examined using Cobas ® EGFR Mutation Test v2. RESULTS: Liquid biopsy detected EGFR mutations in 63.6% of the patients at diagnosis. The presence of metastasis in the extrathoracic, brain, and adrenal glands correlated positively with the detection of EGFR mutations. Patients with positive EGFR mutations at diagnosis had significantly shorter overall and progression-free survival than patients with negative EGFR mutations. Four of the 18 patients (22.2%) who reached progressive disease had positive EGFR T790M mutations. Three of 10 patients (30.0%) with progressive disease were positive and negative for T790M using tumor re-biopsy and liquid biopsy, respectively. The results of EGFR mutation by tissue re-biopsy were the same as those of liquid biopsy in the three patients who were positive for significant EGFR mutations but negative for the T790M mutation using liquid biopsy at progressing disease. Only two patients were positive for major EGFR mutations at intermediate levels. CONCLUSIONS: Liquid biopsy can be a prognostic factor in EGFR-tyrosine kinase inhibitor treatments at diagnosis. Tumor re-biopsy can be omitted in patients with positive EGFR mutations by liquid biopsy at PD.

Down-regulating Nrf2 by tangeretin reverses multiple drug resistance to both chemotherapy and EGFR tyrosine kinase inhibitors in lung cancer.

Multiple drug resistance (MDR) is the major obstacle for both chemotherapy and molecular-targeted therapy for cancer, which is mainly caused by overexpression of ABC transporters or genetic mutation of drug targets. Based on previous studies, we hypothesized that ROS/Nrf2 is the common target for overcoming acquired drug resistance to both targeted therapy and chemotherapy treatments. In this study, we firstly proved that the levels of ROS and Nrf2 were remarkably up-regulated in both H1975 (Gefitinib-resistant lung cancer cells with T790M) and A549/T (paclitaxel-resistant) cells, which is consistent with the clinical database analysis results of lung cancer patients that Nrf2 expression level is negatively related to survival rate. Nrf2 Knockdown with siRNA or tangeretin (TG, a flavonoid isolated from citrus peels) inhibited the MDR cell growth by suppressing the Nrf2 pathway, and efficiently enhanced the anti-tumor effects of paclitaxel and AZD9291 (the third generation of TKI) in A549/T or H1975, respectively. Moreover, TG sensitized A549/T cells-derived xenografts to paclitaxel via inhibiting Nrf2 and its downstream target P-gp, leading to an increased paclitaxel concentration in tumors. Collectively, targeting Nrf2 to enhance ROS may be a common target for overcoming the acquired drug resistance and enhancing the therapeutic effects of chemotherapy and molecular-targeted therapy.

INSIGHT 2: a phase II study of tepotinib plus osimertinib in MET-amplified NSCLC and first-line osimertinib resistance.

MET amplification (METamp), a mechanism of acquired resistance to EGFR tyrosine kinase inhibitors, occurs in up to 30% of patients with non-small-cell lung cancer (NSCLC) progressing on first-line osimertinib. Combining osimertinib with a MET inhibitor, such as tepotinib, an oral, highly selective, potent MET tyrosine kinase inhibitor, may overcome METamp-driven resistance. INSIGHT 2 (NCT03940703), an international, open-label, multicenter phase II trial, assesses tepotinib plus osimertinib in patients with advanced/metastatic EGFR-mutant NSCLC and acquired resistance to first-line osimertinib and METamp, determined centrally by fluorescence in situ hybridization (gene copy number ≥5 and/or MET/CEP7 ≥2) at time of progression. Patients will receive tepotinib 500 mg (450 mg active moiety) plus osimertinib 80 mg once-a-day. The primary end point is objective response, and secondary end points include duration of response, progression-free survival, overall survival and safety. Trial registration number: NCT03940703 (clinicaltrials.gov).

Osimertinib is used to treat a type of lung cancer that has specific changes (mutations) in a gene called EGFR. Although tumors will usually shrink (respond) during treatment with osimertinib, they can stop responding, or become resistant, to osimertinib. A common cause of resistance is 'MET amplification', which describes when extra copies of a gene called MET are present. Lung cancer that is resistant to osimertinib due to MET amplification could be treated by combining osimertinib with a treatment that blocks MET, such as tepotinib. INSIGHT 2 is an ongoing study that is designed to learn about the effects and safety of tepotinib combined with osimertinib, in patients with lung cancer that has stopped responding to osimertinib because of MET amplification. A plain language version of this article is available and is published alongside the paper online: www.futuremedicine.com/doi/suppl/10.2217/fon-2021-1406.

Real-world management patterns in EGFR-mutant advanced non-small-cell lung cancer before first-line adoption of osimertinib: the REFLECT study in Greece.

Aim: To retrospectively characterize real-world therapeutic strategies, clinical outcomes and attrition rates with EGFR tyrosine kinase inhibitors (TKIs), before first-line osimertinib approval, in EGFR-mutated advanced/metastatic non-small-cell lung cancer patients in Greece. Results: Among 160 patients, the discontinuation rate for first-line first- or second-generation EGFR-TKIs was 85%; among these patients, 43% did not receive any second-line therapy and 9.4% died during an 18.7-month follow-up period. Median progression-free and overall survival were 12.1 and 20.9 months, respectively. Osimertinib was offered as second- and third-line treatment in 69.6 and 21.7% of patients with the T790M mutation, respectively. Brain metastases were recorded in 10.6% of patients during treatment, with median overall survival of 4.9 months. Conclusion: Given the high attrition rates and the impact of CNS progression, offering the most appropriate first-line EGFR-TKI treatment with CNS penetration is key to maximize outcomes.

Based on the results of clinical and real-world studies, EGFR tyrosine kinase inhibitors (EGFR-TKIs) are considered the first-line standard of care for people with a type of cancer, know as EGFR-mutant advanced/metastatic non-small-cell lung cancer. However, treatment patterns and outcomes after progression are less well reported and could impact the first-line EGFR-TKI therapeutic approach. This study is part of a large European analysis of real-world evidence, known as the REFLECT study, the objective of which is to learn more about the characterization of testing and treatment patterns, as well as attrition rates, in people receiving first-line treatment with first- or second-generation EGFR-TKIs. Clinical Trial Registration: NCT04031898 (ClinicalTrials.gov) or D5162R00009.

Overcoming C797S mutation: The challenges and prospects of the fourth-generation EGFR-TKIs.

The third-generation epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have accomplished impressive clinical achievements in the treatment of non-small-cell lung cancer (NSCLC). Nonetheless, the acquired drug resistance largely limits their clinical use. The tertiary C797S mutation in the kinase domain of EGFR is one of the major mechanisms responsible for the drug resistance. Therefore, much attention has been focused on the development of the fourth-generation EGFR-TKIs to target triple mutant epidermal growth factor receptor (EGFR) with C797S mutation. In this review, we outline the panorama of the fourth-generation EGFR-TKIs reported up to now with the attention paid on the design strategy, binding mode and antitumor activity of these EGFR-TKIs. We also discuss the challenges and prospects of the fourth-generation EGFR-TKIs.

Response to Brigatinib Targeted Therapy in Non-Small Cell Lung Cancer Harboring Epidermal Growth Factor Receptor Exon 19 Deletion, T790M, and cis-C797S Triple Mutations: A Case Report.

Epidermal growth factor receptor (EGFR) triple mutations with exon 19 deletion (del19), T790M, and cis-C797S (del19/T790M/cis-C797S mutations) frequently occur in patients with non-small cell lung cancer (NSCLC), while progression to frontline EGFR-tyrosine kinase inhibitors (TKIs) and osimertinib was resistant to all clinically available EGFR-TKIs. Brigatinib monotherapy may be a potential treatment for NSCLC harboring del19/T790M/cis-C797S mutations based on preclinical studies; however, no clinical report has evaluated its efficacy on EGFR del19/T790M/cis-C797S mutations. Herein, we present a case of a female patient with EGFR del19-mutated NSCLC treated with afatinib followed by osimertinib due to acquired T790M mutation. The EGFR del19/T790M/cis-C797S mutations were detected following osimertinib treatment. Complete response of skull metastasis was confirmed after brigatinib treatment (90 mg daily). Unfortunately, she experienced intolerable adverse events; therefore, brigatinib was discontinued after three-month usage. This report provides the first reported evidence for the use of brigatinib monotherapy in patients with NSCLC harboring EGFR del19/T790M/cis-C797S mutations after progression to previous EGFR-TKIs.

Quinoxalinones as A Novel Inhibitor Scaffold for EGFR (L858R/T790M/C797S) Tyrosine Kinase: Molecular Docking, Biological Evaluations, and Computational Insights.

Combating acquired drug resistance of EGFR tyrosine kinase (TK) is a great challenge and an urgent necessity in the management of non-small cell lung cancers. The advanced EGFR (L858R/T790M/C797S) triple mutation has been recently reported, and there have been no specific drugs approved for this strain. Therefore, our research aimed to search for effective agents that could impede the function of EGFR (L858R/T790M/C797S) TK by the integration of in silico and in vitro approaches. Our in-house quinoxalinone-containing compounds were screened through molecular docking and their biological activity was then verified by enzyme- and cell-based assay. We found that the four quinoxalinone-containing compounds including CPD4, CPD15, CPD16, and CPD21 were promising to be novel EGFR (L858R/T790M/C797S) TK inhibitors. The IC50 values measured by the enzyme-based assay were 3.04 ± 1.24 nM; 6.50 ± 3.02 nM,10.50 ± 1.10 nM; and 3.81 ± 1.80 nM, respectively, which are at a similar level to a reference drug; osimertinib (8.93 ± 3.01 nM). Besides that, they displayed cytotoxic effects on a lung cancer cell line (H1975) with IC50 values in the range of 3.47 to 79.43 µM. In this proposed study, we found that all screened compounds could interact with M793 at the hinge regions and two mutated residues including M790 and S797; which may be the main reason supporting the inhibitory activity in vitro. The structural dynamics revealed that the screened compounds have sufficient non-native contacts with surrounding amino acids and could be well-buried in the binding site's cleft. In addition, all predicted physicochemical parameters were favorable to be drug-like based on Lipinski's rule of five, and no extreme violation of toxicity features was found. Altogether, this study proposes a novel EGFR (L858R/T790M/C797S) TK inhibitor scaffold and provides a detailed understanding of compounds' recognition and susceptibility at the molecular level.

EGFR Tyrosine Kinase Inhibitor Efficacy in Older Adult Patients with Advanced EGFR-Mutated Non-Small-Cell Lung Cancer: A Meta-Analysis and Systematic Review.

Background and Objectives: Lung cancer remains the most common malignancy worldwide. As the global population ages, the prevalence of epidermal growth factor receptor (EGFR)-mutation-positive non-small cell lung cancer (NSCLC) is increasing. Materials and Methods: We performed a meta-analysis and a systematic review of randomized, controlled trials to evaluate the efficacy of EGFR TKIs on progression-free survival (PFS) and overall survival (OS) in older adult patients with advanced EGFR-mutated NSCLC. A total of 1327 patients were included; among these, 662 patients were >65 years of age. Results: A pooled analysis indicated (1) an overall improvement in higher PFS for dacomitinib and osimetinib than that for other drugs (hazard ratio [HR] = 0.654, 95% CI: 0.474 to 0.903; p = 0.01) and (2) and no significant difference in the OS between the EGFR TKIs (HR = 0.989, 95% CI: 0.796 to 1.229; p = 921). Conclusion: Our study found that osimertinib achieved a higher PFS than all other EGFR TKIs did. Osimertinib is the preferred EGFR TKI for treatment of older adult patients with advanced EGFR-mutated NSCLC.

Celastrol acts synergistically with afatinib to suppress non-small cell lung cancer cell proliferation by inducing paraptosis.

Non-small cell lung cancer (NSCLC) with wild-type epidermal growth factor receptor (EGFR) is intrinsic resistance to EGFR-tyrosine kinase inhibitors (TKIs), such as afatinib. Celastrol, a natural compound with antitumor activity, was reported to induce paraptosis in cancer cells. In this study, intrinsic EGFR-TKI-resistant NSCLC cell lines H23 (EGFR wild-type and KRAS mutation) and H292 (EGFR wild-type and overexpression) were used to test whether celastrol could overcome primary afatinib resistance through paraptosis induction. The synergistic effect of celastrol and afatinib on survival inhibition of the NSCLC cells was evaluated by CCK-8 assay and isobologram analysis. The paraptosis and its modulation were assessed by light and electron microscopy, Western blot analysis, and immunofluorescence. Xenografts models were established to investigate the inhibitory effect of celastrol plus afatinib on the growth of the NSCLC tumors in vivo. Results showed that celastrol acted synergistically with afatinib to suppress the survival of H23 and H292 cells by inducing paraptosis characterized by extensive cytoplasmic vacuolation. This process was independent of apoptosis and not associated with autophagy induction. Afatinib plus celastrol-induced cytoplasmic vacuolation was preceded by endoplasmic reticulum stress and unfolded protein response. Accumulation of intracellular reactive oxygen species and mitochondrial Ca2+ overload may be initiating factors of celastrol/afatinib-induced paraptosis and subsequent cell death. Furthermore, Celastrol and afatinib synergistically suppressed the growth of H23 cell xenograft tumors in vivo. The data indicate that a combination of afatinib and celastrol may be a promising therapeutic strategy to surmount intrinsic afatinib resistance in NSCLC cells.

Clinical utility of liquid biopsy for EGFR driver, T790M mutation and EGFR amplification in plasma in patients with acquired resistance to afatinib.

BACKGROUND: Cell-free DNA (cfDNA) genotyping in plasma using the cobas EGFR Mutation Test v2 (cobas) is the first liquid biopsy as a companion diagnosis to identify the EGFR T790M mutation (T790M) after the failure of treatment of EGFR-tyrosine kinase inhibitors (TKIs) (1st generation, gefitinib [G] and erlotinib [E] and 2nd generation, afatinib [A]). This study investigated the clinical utility of a liquid biopsy for patients who acquired resistance to afatinib. METHODS: We prospectively collected plasma from 51 patients who had acquired resistance to afatinib between April 2015 and November 2016 to evaluate the frequency of T790M by cobas and digital droplet PCR (UMIN000025112). Additionally, we retrospectively reviewed 38 patients who tested by cobas in plasma after G/E failure to compare for T790M detection between A and with G/E. RESULTS: The detection rate of EGFR-driver and T790M in plasma in patients treated with A (A group) as a first-line EGFR-TKI was lower than with G/E followed by A (G/E→A group), although the differences were not significant (EGFR-driver: 41% [A] vs. 67% [G/E→A], P=0.1867; and T790M: 8% [A] vs. 17% [G/E→A], P=0.5798). In first-line setting, the detection rate for EGFR-driver and T790M in plasma by cobas was lower in A group than in G/E group, although there was no significant difference (EGFR-driver: 34% [A] vs. 52% [G/E], P=0.2072; and T790M: 10% [A] vs. 27% [G/E], P=0.1161). CONCLUSION: The detection of EGFR-driver and T790M in plasma by cobas in patients treated with afatinib might be lower than with G/E in a real-world setting.

Synthesis and evaluation of azalamellarin N and its A-ring-modified analogues as non-covalent inhibitors of the EGFR T790M/L858R mutant.

Azalamellarin N, a synthetic lactam congener of the marine natural product lamellarin N, and its A-ring-modified analogues were synthesized and evaluated as potent and non-covalent inhibitors of the drug-resistant epidermal growth factor receptor T790M/L858R mutant. An in vitro tyrosine kinase assay indicated that the inhibitory activities of the synthetic azalamellarin analogues were higher than those of the corresponding lamellarins. The azalamellarin analogue bearing two 3-(dimethylamino)propoxy groups at C20- and C21-positions exhibited the highest activity and selectivity against the mutant kinase [IC50 (T790M/L858R) = 1.7 nM; IC50 (WT) = 4.6 nM]. The inhibitory activity was attributed to the hydrogen bonding interaction between the lactam NH group of the B-ring and carbonyl group of a methionine residue.

Systemic Therapy for Lung Cancer Brain Metastases.

OPINION STATEMENT: Systemic therapy for brain metastases (BM) is quickly moving from conventional cytotoxic chemotherapy toward targeted therapies, that allow a disruption of driver molecular pathways. The discovery of actionable driver mutations has led to the development of an impressive number of tyrosine kinase inhibitors (TKIs), that target the epidermal growth factor receptor (EGFR) mutations, anaplastic-lymphoma-kinase (ALK) rearrangements, and other rare molecular alterations in patients bearing metastatic non-small cell lung cancer (NSCLC) in the brain, with remarkable results in terms of intracranial disease control and overall survival. Moreover, these drugs may delay the use of local therapies, such as stereotactic radiosurgery (SRS) or whole-brain radiotherapy (WBRT). New drugs with higher molecular specificity and ability to cross the CNS barriers (BBB, BTB and blood-CSF) are being developed. Two major issues are related to targeted therapies. First, the emergence of a resistance is a common event, and a deeper understanding of molecular pathways that are involved is critical for the successful development of effective new targeted agents. Second, an early detection of tumor progression is of utmost importance to avoid the prolongation of an ineffective therapy while changing to another drug. In order to monitor over time the treatment to targeted therapies, liquid biopsy, that allows the detection in biofluids of either circulating tumor cells (CTCs) or circulating tumor DNA (ctDNA) or exosomes, is increasingly employed in clinical trials: with respect to BM the monitoring of both blood and CSF is necessary. Also, radiomics is being developed to predict the mutational status of the BM on MRI.For patients without druggable mutations or who do not respond to targeted agents, immunotherapy with checkpoint inhibitors is increasingly employed, alone or in combination with radiotherapy. Pseudoprogression after immunotherapy alone maybe a challenge for several months after the start of treatment, and the same is true for radionecrosis after the combination of immunotherapy and SRS. In this regard, the value of advanced MRI techniques and PET imaging for a better distinction of pseudoprogression/radionecrosis and true tumor progression is promising, but needs validation in large prospective datasets. Last, a new frontier in the near future will be chemoprevention (primary and secondary), but we need to identify among solid tumors those subgroups of patients with a higher risk of relapsing into the brain and novel drugs, active on either neoplastic or normal cells of the microenvironment, that are cooperating in the invasion of brain tissue.