EGFR Gene Copy Number by FISH May Predict Outcome of Necitumumab in Squamous Lung Carcinomas: Analysis from the SQUIRE Study

Frequency and functional characterization of fusion genes in squamous cell carcinoma of the lung

INTRODUCTION

In contrast to lung adenocarcinoma (LUAD), targetable genetic alterations are less frequently detected in squamous cell carcinoma of the lung (LUSC). Over the last years, gene fusions have become promising targets in many solid cancers. Here, we analysed a cohort of LUSC, identified recurrent fusion genes and functionally characterised these tumour genomes.

METHODS

A subset of 1608 squamous cell carcinomas of the lung was analysed by means of the FusionPlex® Lung Panel to identify potentially targetable gene fusions using targeted next-generation sequencing. Cases harbouring recurrent gene fusions were further analysed using FISH, Cytoscan HD arrays and cell culture experiments.

RESULTS

We found both, known and novel gene fusions in about 3 % of the cases. Known fusions occurring in lung cancer included ALK::EML4, EGFRvIII, EZR::ROS1 and FGFR3::TACC. We further identified recurrent gene fusions of currently unknown biological function, involving EGFR::VSTM2A and NSD3::FGFR1 and showed that the occurrence of the EGFR::VSTM2A fusion is accompanied by high-level amplification of EGFR. Our analyses further revealed that the genomes of these LUSC patients are chromosomally unstable, which leads us to believe that such non-actionable genomic rearrangements may be a result of "chromosomal chaos" most probably not representing exclusive cancer-driving genes in this cancer entity.

CONCLUSIONS

We emphasise that caution should be taken when novel fusions are found and that the appearance of new gene fusions should always be interpreted in the molecular context of the respective disease.

Integrative analysis of non-small cell lung cancer patient-derived xenografts identifies distinct proteotypes associated with patient outcomes

Non-small cell lung cancer (NSCLC) is the leading cause of cancer deaths worldwide. Only a fraction of NSCLC harbor actionable driver mutations and there is an urgent need for patient-derived model systems that will enable the development of new targeted therapies. NSCLC and other cancers display profound proteome remodeling compared to normal tissue that is not predicted by DNA or RNA analyses. Here, we generate 137 NSCLC patient-derived xenografts (PDXs) that recapitulate the histology and molecular features of primary NSCLC. Proteome analysis of the PDX models reveals 3 adenocarcinoma and 2 squamous cell carcinoma proteotypes that are associated with different patient outcomes, protein-phosphotyrosine profiles, signatures of activated pathways and candidate targets, and in adenocarcinoma, stromal immune features. These findings portend proteome-based NSCLC classification and treatment and support the PDX resource as a viable model for the development of new targeted therapies.

With non-small cell lung cancer (NSCLC) being the leading cause of cancer deaths worldwide, the development of targeted therapies remains crucial. Here, the generation and multi-omics characterization of 137 NSCLC patient-derived xenografts provides a resource for potential classifications and targets.

EGFR High Copy Number Together With High EGFR Protein Expression Predicts Improved Outcome for Cetuximab-based Therapy in Squamous Cell Lung Cancer: Analysis From SWOG S0819, a Phase III Trial of Chemotherapy With or Without Cetuximab in Advanced NSCLC

BACKGROUND

The phase III S0819 trial investigated addition of cetuximab to first-line chemotherapy (CT) in NSCLC. Subgroup analyses suggested an OS benefit among patients with EGFR copy number gain in squamous cell carcinomas (SCC), (HR = 0.58 [0.39-0.86], P = .0071). A more detailed model based on EGFR FISH, EGFR IHC and KRAS mutation status was evaluated to yield a more precise predictive paradigm of cetuximab-based therapy in advanced NSCLC.

METHODS

FISH was performed using the Colorado Scoring Criteria; H-Score was used to quantify EGFR IHC expression (cut-off ≥ 200). A Cox model was used to assess treatment effects for OS and PFS within biomarker and clinical subgroups. KRAS mutation was analyzed using Therascreen. The false discovery rate controlled for multiple comparisons. S0819 ClinicalTrials.gov Identifier: NCT00946712.

RESULTS

Of 1,313 eligible patients, assay results were obtained for FISH on 976 patients (41% positive), for IHC on 945 patients (31% positive), and KRAS mutation status on 627 patients (26% positive). In SCC patients, OS was significantly improved with addition of cetuximab when both EGFR FISH and EGFR IHC were positive (N = 58), (OS HR: 0.32 [95% CI 0.18-0.59]; P = .0002, q = 0.08), median 12.6 versus 4.6 months. The results were independent of KRAS mutation status. In Non-SCC, no predictive value of EGFR IHC, EGFR FISH status and/or KRAS status was seen.

CONCLUSIONS

In NSCLC SCC, a combination index of EGFR FISH plus EGFR IHC results was associated with improved OS when cetuximab was added to CT, representing a potential predictive molecular paradigm for patients suitable for EGFR-antibody therapy.

Application of the conventional and novel methods in testing EGFR variants for NSCLC patients in the last 10 years through different regions: a systematic review

Variants in the epidermal growth factor receptor (EGFR) gene are recognized as predictors of therapy response and are correlated with progression-free and overall survival in non-small cell lung cancer (NSCLC) patients. Molecularly guided therapy needs precise and cost-effective molecular tests. This review focused primarily on screening or target methods for the EGFR variants detection with diagnostic and prognostic potential in the clinical research published papers. Concerning the inclusion and exclusion criteria, the search interval comprised available articles published from 2010 until 2020 in three electronic databases, ISI Web of Science, Pub Med, and Scopus. The analysis of eligible studies started with 5647 and obtained the final 987 full-text articles analyzed as clinical research. The regions comprised were Africa, America, Australia, Asia, Euro-Asia, Europe, or a consortium of different countries. All of the tested methods were applied prevalently in Asia. In clinical research, the polymerase chain reaction (PCR), followed by sequencing methods have been involved mostly over the years. The identified high-through output approaches evolved to improve the survival and quality of the NSCLC patient's life becoming more sensitive, specific, and cost-effective.

Objective Quantitation of EGFR Protein Levels using Quantitative Dot Blot Method for the Prognosis of Gastric Cancer Patients

Purpose

An underlying factor for the failure of several clinical trials of anti-epidermal growth factor receptor (EGFR) therapies is the lack of an effective method to identify patients who overexpress EGFR protein. The quantitative dot blot method (QDB) was used to measure EGFR protein levels objectively, absolutely, and quantitatively. Its feasibility was evaluated for the prognosis of overall survival (OS) of patients with gastric cancer.

Materials and Methods

Slices of 2×5 μm from formalin-fixed paraffin-embedded gastric cancer specimens were used to extract total tissue lysates for QDB measurement. Absolutely quantitated EGFR protein levels were used for the Kaplan-Meier OS analysis.

Results

EGFR protein levels ranged from 0 to 772.6 pmol/g (n=246) for all gastric cancer patients. A poor correlation was observed between quantitated EGFR levels and immunohistochemistry scores with ρ=0.024 and P=0.717 in Spearman's correlation analysis. EGFR was identified as an independent negative prognostic biomarker for gastric cancer patients only through absolute quantitation, with a hazard ratio of 1.92 (95% confidence interval, 1.05–3.53; P=0.034) in multivariate Cox regression OS analysis. A cutoff of 208 pmol/g was proposed to stratify patients with a 3-year survival probability of 44% for patients with EGFR levels above the cutoff versus 68% for those below the cutoff based on Kaplan-Meier OS analysis (log rank test, P=0.002).

Conclusions

A QDB-based assay was developed for gastric cancer specimens to measure EGFR protein levels absolutely, quantitatively, and objectively. This assay should facilitate clinical trials aimed at evaluation of anti-EGFR therapies retrospectively and prospectively for gastric cancer.

Advanced Squamous Cell Carcinoma of the Lung: Current Treatment Approaches and the Role of Afatinib

Options for the treatment of squamous cell lung carcinoma expanded in recent years with the introduction of the immune checkpoint inhibitors into routine clinical practice in both the first- and second-line settings but are still limited. As a result, pembrolizumab, given either alone or in combination with platinum-based chemotherapy, is now a standard first-line treatment for squamous cell lung cancer. However, few options exist once patients have progressed on immune checkpoint inhibitors and chemotherapy. In this setting, the irreversible ErbB family blocker, afatinib, has a potential role as second or subsequent therapy for some patients. The Phase III LUX-Lung 8 study demonstrated that afatinib significantly prolonged progression-free and overall survival compared with erlotinib in patients with squamous cell lung carcinoma. Notably, retrospective, ad-hoc biomarker analyses of a subset of patients from LUX-Lung 8 suggested that patients with ErbB family mutations derived particular benefit from afatinib, especially those with ErbB2 (HER2) mutations. Afatinib has a manageable and predictable safety profile, and adverse events can be managed with the use of a tolerability-guided dose modification protocol. Until more data are available, afatinib could be considered as a potential second-line treatment option for patients who have progressed on combined pembrolizumab and platinum-based chemotherapy and are ineligible for more established second-line options, or as a third-line option in patients who have received first-line immunotherapy, and second-line chemotherapy or chemotherapy and antiangiogenesis therapy. However, further data are required to support the use of afatinib following immunotherapy. Given that treatment options are limited in both of these settings, investigating an agent with an entirely new mechanism of action is warranted. If available, molecular analysis to identify ErbB family mutations or the use of proteomic profiling could help to further isolate patients who are likely to derive the most benefit from afatinib.

Efficacy and safety of necitumumab and pembrolizumab combination therapy in patients with Stage IV non-small cell lung cancer

OBJECTIVES

Efficacy and safety of necitumumab when combined with pembrolizumab was assessed in patients with Stage IV non-small cell lung cancer (NSCLC) of squamous and nonsquamous histology, who had progressed after treatment with a platinum-based doublet.

MATERIALS AND METHODS

This single-arm, multicenter, phase Ib study had a dose-finding phase, in which escalating doses of necitumumab (600 mg and 800 mg IV) were administered on Day 1 and 8 every 3 weeks (Q3W) in combination with pembrolizumab (200 mg IV) on Day 1 Q3W, and expansion cohorts. Patients were treated until progressive disease (PD), toxicity requiring cessation, protocol noncompliance, or withdrawal of consent. Efficacy was evaluated by overall response rate (ORR).

RESULTS

In 64 treated patients (32 patients [50 %] were programmed death-ligand 1 [PD-L1] negative), confirmed ORR was 23.4 % (95 % confidence interval [CI] 13.8 %-35.7 %). Two patients (3.1 %) had complete response (CR), 13 patients (20.3 %) had partial response (PR), 26 patients (40.6 %) had stable disease, 17 patients (26.6 %) had PD, and 6 patients (9.4 %) were not evaluable. Regardless of histology or PD-L1 status, median PFS (mPFS) was 4.1 months (95 % CI 2.4-6.9 months) and OS at 6 months was 74.7 % (61.5%-83.9%). Confirmed disease control rate was 64.1 % (95 % CI 51.5-75.7). Patients with programmed death-ligand 1 (PD-L1) ≥1% had numerically improved ORR and median progression-free survival when compared with patients with PD-L1 negative cancer. No dose-limiting toxicities were recorded and the combination of necitumumab 800 mg with pembrolizumab 200 mg was considered tolerable.

CONCLUSION

Results suggest modest benefits of second-line necitumumab and pembrolizumab combination therapy in patients with Stage IV NSCLC. Safety profiles were consistent with class effects typical of epidermal growth factor receptor inhibitors and immunotherapies with no additive toxicities.

Necitumumab for the treatment of advanced non-small-cell lung cancer

Personalized patient-precise medicine is being gradually incorporated into clinical practice for the treatment of non-small-cell lung cancer (NSCLC). The EGFR pathway has been explored as a druggable target with monoclonal antibodies such as cetuximab or necitumumab. Necitumumab is a humanized IgG1 anti-EGFR. In the Phase III SQUIRE trial, necitumumab used as first-line therapy in combination with cisplatin and gemcitabine showed a reduction in risk-of-death and a better disease control rate in advanced squamous NSCLC. Thus, necitumumab is now a new first-line treatment option in squamous NSCLC. However, further biomarker research is needed to improve patient selection. Moreover, necitumumab associated with other immunotherapy and targeted agents is currently an important area of research that may yield better outcomes for NSCLC patients.