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Background Blood-based biomarkers of anti-solid tumor immune checkpoint blockade (ICB) response are lacking. We hypothesized that changes in systemic cytokine levels with the initial doses of programmed cell death protein 1 (PD-1) pathway inhibitors would correlate with clinical responses. New ultrasensitive ELISA technology enables quantitation of plasma proteins in sub-picogram-per-milliliter concentrations.Methods We measured plasma cytokines by ultrasensitive single-molecule array assays in patients with non-small-cell lung carcinoma before and during treatment with anti-PD-1 therapy. Association with best overall response and progression-free survival (PFS) was assessed by Kruskall-Wallis test and Kaplan-Meier plots with log-rank test, respectively.Results A decrease in interleukin 6 (IL-6) levels was associated with improved PFS (n=47 patients, median PFS: 11 vs 4 months, HR 0.45 (95% CI 0.23 to 0.89), p=0.04). The extent of change in IL-6 differed between best overall response categories (p=0.01) and correlated with changes in C reactive protein levels. We also explored plasma cytokine levels in relation to immune-related adverse effects and observed some correlation.Conclusions This study suggests the presence of a systemic, proteomic reflection of successful ICB outside the tumor microenvironment with plasma decreases in IL-6 and CRP.

We aimed to investigate prevalence and prognostic role of SOX2, PIK3CA, FGFR1 and BRF2 gene gain in patients with surgically resected non-small cell lung cancer (NSCLC).SOX2, PIK3CA, FGFR1 and BRF2 gene copy number was assessed by fluorescence in situ hybridization (FISH) in arrayed tissue cores from 447 resected NSCLCs.Increased gene copy number (FISH+) for SOX2, PIK3CA, FGFR1 and BRF2 was observed in 23.6%, 29.2%, 16.6% and 14.9% of cases, respectively. FISH+ status for each gene was significantly associated with smoking history, squamous cell carcinoma (SCC) histology, and increased copy number of the other studied genes. Multivariate analysis of overall survival indicated increased SOX2 gene copy number (P = 0.008), stage I-II (P

Somatic mutations in the kinase domain of the epidermal growth factor receptor tyrosine kinase gene EGFR are common in lung adenocarcinoma. The presence of mutations correlates with tumor sensitivity to the EGFR inhibitors erlotinib and gefitinib, but the transforming potential of specific mutations and their relationship to drug sensitivity have not been described.Here, we demonstrate that EGFR active site mutants are oncogenic. Mutant EGFR can transform both fibroblasts and lung epithelial cells in the absence of exogenous epidermal growth factor, as evidenced by anchorage-independent growth, focus formation, and tumor formation in immunocompromised mice. Transformation is associated with constitutive autophosphorylation of EGFR, Shc phosphorylation, and STAT pathway activation. Whereas transformation by most EGFR mutants confers on cells sensitivity to erlotinib and gefitinib, transformation by an exon 20 insertion makes cells resistant to these inhibitors but more sensitive to the irreversible inhibitor CL-387,785.Oncogenic transformation of cells by different EGFR mutants causes differential sensitivity to gefitinib and erlotinib. Treatment of lung cancers harboring EGFR exon 20 insertions may therefore require the development of alternative kinase inhibition strategies.

Despite the success of KRAS G12C inhibitors in non–small cell lung cancer (NSCLC), more effective treatments are needed. One preclinical strategy has been to cotarget RAS and mTOR pathways; however, toxicity due to broad mTOR inhibition has limited its utility. Therefore, we sought to develop a more refined means of targeting cap-dependent translation and identifying the most therapeutically important eukaryotic initiation factor 4F complex–translated (eIF4F-translated) targets. Here, we show that an eIF4A inhibitor, which targets a component of eIF4F, dramatically enhances the effects of KRAS G12C inhibitors in NSCLCs and together these agents induce potent tumor regression in vivo. By screening a broad panel of eIF4F targets, we show that this cooperativity is driven by effects on BCL-2 family proteins. Moreover, because multiple BCL-2 family members are concomitantly suppressed, these agents are broadly efficacious in NSCLCs, irrespective of their dependency on MCL1, BCL-xL, or BCL-2, which is known to be heterogeneous. Finally, we show that MYC overexpression confers sensitivity to this combination because it creates a dependency on eIF4A for BCL-2 family protein expression. Together, these studies identify a promising therapeutic strategy for KRAS-mutant NSCLCs, demonstrate that BCL-2 proteins are the key mediators of the therapeutic response in this tumor type, and uncover a predictive biomarker of sensitivity.

Inhibitors that target the receptor tyrosine kinase (RTK)/Ras/mitogen-activated protein kinase (MAPK) pathway have led to clinical responses in lung and other cancers, but some patients fail to respond and in those that do resistance inevitably occurs (Balak et al., 2006; Kosaka et al., 2006; Rudin et al., 2013; Wagle et al., 2011). To understand intrinsic and acquired resistance to inhibition of MAPK signaling, we performed CRISPR-Cas9 gene deletion screens in the setting of BRAF, MEK, EGFR, and ALK inhibition. Loss of KEAP1, a negative regulator of NFE2L2/NRF2, modulated the response to BRAF, MEK, EGFR, and ALK inhibition in BRAF-, NRAS-, KRAS-, EGFR-, and ALK-mutant lung cancer cells. Treatment with inhibitors targeting the RTK/MAPK pathway increased reactive oxygen species (ROS) in cells with intact KEAP1, and loss of KEAP1 abrogated this increase. In addition, loss of KEAP1 altered cell metabolism to allow cells to proliferate in the absence of MAPK signaling. These observations suggest that alterations in the KEAP1/NRF2 pathway may promote survival in the presence of multiple inhibitors targeting the RTK/Ras/MAPK pathway.

Fusion genes have been proposed as a potential mechanism of resistance to EGFR tyrosine kinase inhibitors (TKIs) in lung cancer. Here, the authors identify gene fusions that are associated with resistance to EGFR TKIs in non-small cell lung cancers, and test how these fusions impact the response to EGFR TKIs in vitro.

Acquired drug resistance is common during chemotherapy. Here, the authors describe the structural basis and molecular mechanism by which allosteric and clinically approved, ATP-competitive inhibitors of EGFR synergize to overcome resistance in lung cancer.

Small‐cell lung cancer (SCLC) occurs infrequently in never/former light smokers. We sought to study this rare clinical subset through next‐generation sequencing (NGS) and by characterizing a representative patient‐derived model. We performed targeted NGS, as well as comprehensive pathological evaluation, in 11 never/former light smokers with clinically diagnosed SCLC. We established a patient‐derived model from one such patient (DFCI168) harboring an NRASQ61K mutation and characterized the sensitivity of this model to MEK and TORC1/2 inhibitors. Despite the clinical diagnosis of SCLC, the majority (8/11) of cases were either of nonpulmonary origin or of mixed histology and included atypical carcinoid (n = 1), mixed non‐small‐cell lung carcinoma and SCLC (n = 4), unspecified poorly differentiated carcinoma (n = 1), or small‐cell carcinoma from different origins (n = 2). RB1 and TP53 mutations were found in four and five cases, respectively. Predicted driver mutations were detected in EGFR (n = 2), NRAS (n = 1), KRAS (n = 1), BRCA1 (n = 1), and ATM (n = 1), and one case harbored a TMPRSS2‐ERG fusion. DFCI168 (NRASQ61K) exhibited marked sensitivity to MEK inhibitors in vitro and in vivo. The combination of MEK and mTORC1/2 inhibitors synergized to prevent compensatory mTOR activation, resulting in prolonged growth inhibition in this model and in three other NRAS mutant lung cancer cell lines. SCLC in never/former light smokers is rare and is potentially a distinct disease entity comprised of oncogenic driver mutation‐harboring carcinomas morphologically and/or clinically mimicking SCLC. Comprehensive pathologic review integrated with genomic profiling is critical in refining the diagnosis and in identifying potential therapeutic options.

Introduction: Abemaciclib is an oral, selective small-molecule CDK 4 and 6 inhibitor. In preclinical models, abemaciclib synergized with programmed cell death protein-1 blockade to enhance antitumor efficacy. Here, we report the safety and anticancer activity of abemaciclib plus pembrolizumab in two cohorts with NSCLC. Methods: This nonrandomized, open-label, phase 1b study included patients with previously untreated programmed death-ligand 1–positive, KRAS-mutant nonsquamous metastatic NSCLC (cohort A); squamous NSCLC after one previous platinum-containing chemotherapy regimen for metastatic disease (cohort B); and two breast cancer cohorts (disclosed separately). Patients received 150 mg abemaciclib every 12 hours plus 200 mg pembrolizumab intravenously on day 1 every 21 days. The primary objective was safety; secondary objectives included objective response rate, disease control rate, progression-free survival, and overall survival. Clinical Trial Number: NCT02779751. Results: Each cohort enrolled 25 patients. Grades greater than or equal to 3 treatment-emergent adverse events in cohorts A and B were reported by 20 (80%) and 19 patients (76%), respectively. Six patients in cohort A (24.0%) and two patients in cohort B (8.0%) had a confirmed partial response; disease control rate was 56% and 64%, respectively. Median progression-free survival was 7.6 months (95% confidence interval [CI]: 1.6–not estimable) and 3.3 months (95% CI: 1.4–5.2); median overall survival was 27.8 months (95% CI: 9.9–not estimable) and 6.0 months (95% CI: 3.7–13.1) in cohorts A and B, respectively. Conclusions: The combination of abemaciclib and pembrolizumab in stage IV NSCLC resulted in greater toxicity compared with that previously reported for each individual treatment. Risk-benefit profile does not warrant further evaluation of the combination in this population.

Background: KRAS mutations are the most frequent oncogenic aberration in lung adenocarcinoma. KRAS mutant isoforms differentially shape tumour biology and influence drug responses. This heterogeneity challenges the development of effective therapies for patients with KRAS-driven non-small cell lung cancer (NSCLC). Methods: We developed an integrative pharmacogenomics analysis to identify potential drug targets to overcome MEK/ERK inhibitor resistance in lung cancer cell lines with KRAS(G12C) mutation (n = 12). We validated our predictive in silico results with in vitro models using gene knockdown, pharmacological target inhibition and reporter assays. Findings: Our computational analysis identifies casein kinase 2A1 (CSNK2A1) as a mediator of MEK/ERK inhibitor resistance in KRAS(G12C) mutant lung cancer cells. CSNK2A1 knockdown reduces cell proliferation, inhibits Wnt/β-catenin signalling and increases the anti-proliferative effect of MEK inhibition selectively in KRAS(G12C) mutant lung cancer cells. The specific CK2-inhibitor silmitasertib phenocopies the CSNK2A1 knockdown effect and sensitizes KRAS(G12C) mutant cells to MEK inhibition. Interpretation: Our study supports the importance of accurate patient stratification and rational drug combinations to gain benefit from MEK inhibition in patients with KRAS mutant NSCLC. We develop a genotype-based strategy that identifies CK2 as a promising co-target in KRAS(G12C) mutant NSCLC by using available pharmacogenomics gene expression datasets. This approach is applicable to other oncogene driven cancers. Fund: This work was supported by grants from the National Natural Science Foundation of China, the National Key Research and Development Program of China, the Lung Cancer Research Foundation and a Mildred-Scheel postdoctoral fellowship from the German Cancer Aid Foundation. Keywords: Pharmacogenomic profiles, KRAS mutations, Lung adenocarcinoma, CSNK2A1, CK2, MEK inhibitor, Silmitasertib, Wnt/β-catenin, EMT

Introduction: Taletrectinib (AB-106/DS-6051b) is an oral, potent selective ROS1 and pan-NTRK tyrosine kinase inhibitor (TKI). Preclinically, taletrectinib has activity against ROS1 G2032R solvent-front mutation. Methods: Patients with ROS1+ NSCLC enrolled into two phase 1 studies conducted in United States (U101, NCT02279433) and Japan (J102, NCT02675491) were analyzed for objective response rate (ORR) by the Response Evaluation Criteria in Solid Tumors version 1.1, progression-free survival, and safety. Results: A total of 22 patients with ROS1+ NSCLC out of the total 61 patients enrolled were analyzed. Taletrectinib was given at the oral dose of 400 mg, 600 mg, 800 mg, and 1200 mg once daily and 400 mg twice daily as part of the dose-escalation schema. Data cutoff was August 19, 2020. Median follow-up time for all 22 patients was 14.9 months (95% confidence interval [CI]: 4.1–33.8). A total of 18 patients with ROS1+ were assessable for response. The confirmed ORR for ROS1 TKI-naive patients (N = 9) was 66.7% (95% CI: 35.4–87.9) with a disease control rate of 100% (70.1–100). The confirmed ORR for crizotinib pretreated patients (N = 6) was 33.3% (95% CI: 9.7–70.0) with a disease control rate of 88.3% (95% CI: 443.6–97.0). The median progression-free survival for ROS1 TKI-naive patients (N = 11) was 29.1 months (95% CI: 2.6–not reached) and 14.2 months (95% CI: 1.5–not reached) for crizotinib-refractory only patients (N = 8). The most common treatment-related adverse events were alanine transaminase elevations (72.7%), aspartate transaminase elevations (72.7%), nausea (50.0%), and diarrhea (50.0%). Grade 3 or higher adverse events were alanine transaminase elevations (18.2%), aspartate transaminase (9.1%), and diarrhea (4.5%). Conclusions: Taletrectinib (AB106/DS6051b) has a meaningful clinical activity in patients with advanced ROS1+ NSCLC who are ROS1 TKI-naive or crizotinib-refractory and a manageable safety profile.

The discovery of epidermal growth factor receptor (EGFR) mutations in nonsmall cell lung cancer (NSCLC) has allowed the identification of a subset of patients whose tumours are exquisitely sensitive to EGFR tyrosine kinase inhibitors (TKIs). Despite the efficacy and superiority of EGFR TKIs over chemotherapy as first-line therapy, all patients will ultimately develop progressive disease, with a median of 9–13 months progression-free survival. A better understanding of the molecular mechanisms underlying resistance to EGFR TKIs can help design new drugs and therapeutic strategies to overcome resistance. This has been illustrated by the new generation TKIs that are effective on the T790M mutation, which is the most frequent mechanism of acquired resistance to EGFR TKIs. In this article, we will address the main molecular mechanisms of primary and acquired resistance to EGFR TKIs in EGFR-mutant NSCLC.

Lung cancer in never-smokers is an important disease often characterized by mutations in epidermal growth factor receptor (EGFR), yet risk reduction measures and effective chemopreventive strategies have not been established. We identify mammalian target of rapamycin (mTOR) as potentially valuable target for EGFR mutant lung cancer. mTOR is activated in human lung cancers with EGFR mutations, and this increases with acquisition of T790M mutation. In a mouse model of EGFR mutant lung cancer, mTOR activation is an early event. As a single agent, the mTOR inhibitor rapamycin prevents tumor development, prolongs overall survival, and improves outcomes after treatment with an irreversible EGFR tyrosine kinase inhibitor (TKI). These studies support clinical testing of mTOR inhibitors in order to prevent the development and progression of EGFR mutant lung cancers.