Targeting HER2 aberrations as actionable drivers in lung cancers: phase II trial of the pan-HER tyrosine kinase inhibitor dacomitinib in patients with HER2-mutant or amplified tumors

Antitumour effects and mechanisms of action of the panHER inhibitor, dacomitinib, alone and in combination with the STAT3 inhibitor, S3I-201, in human sarcoma cell lines

The 5-year survival rate for metastatic sarcoma is 16%. Although the phosphorylated human epidermal growth factor receptor (pEGFR/HER1) has been shown to be an independent predictor of overall survival in patients with sarcoma, we have previously demonstrated that sarcoma cell lines exhibit resistance, despite gefitinib blocking p-EGFR and signal transducers in EGFR downstream pathways. Gefitinib failed to decrease the ratio of phosphorylated (p-)signal transducer and activator of transcription (STAT3)/p-STAT1, suggesting that relative STAT3 abundance and activation may be involved in drug resistance. In this study, we used the panHER inhibitor, dacomitinib, to further block HER2-dependent activation, applying multiple methods, such as proliferation assay, clonogenic survival assay, anti-anoikis assay and western blot analysis. Although dacomitinib inhibited EGFR, HER2, AKT and Erk activation more effectively than gefitinib, it still only exerted minimal anti-proliferative effects on sarcoma cell lines due to the STAT3 escape pathway. However, the addition of the STAT3 inhibitor, S3I-201, to dacomitinib achieved a significant enhancement in growth inhibition, by perturbing p-STAT3/p-STAT1. Using a panel of sarcoma cell lines with different histological types, we identified that the addition of the STAT3 inhibitor enhanced the growth inhibitory effects of the panHER inhibitor, dacomitinib, on sarcoma cells. Our findings may have clinical implications on overcoming the resistance caused by the STAT3 escape pathway and optimising EGFR/panHER-targeted therapy in sarcoma.

Outcomes of Pemetrexed-based chemotherapies in HER2-mutant lung cancers

Background

HER2 mutation has been found to be an oncogenic driver gene in non-small cell lung cancers(NSCLC) and HER2-directed therapies have shown promising results in this unique population, while little is known about its association with outcomes of chemotherapy. The aim of this study was to investigate the efficacy of first line chemotherapy in patients with advanced HER2-mutant lung adenocarcinomas.

Methods

Patients with advanced NSCLC(N = 1714) initially underwent testing for EGFR, KRAS, BRAF mutations and ALK, ROS1 rearrangements, and negative cases were then assessed for HER2 mutations using the method of amplification refractory mutation system(ARMS). The efficacy of first line pemetrexed-based chemotherapy was investigated in patients with HER2-mutant and those with EGFR-mutant, ALK/ROS1-rearranged and KRAS-mutant advanced adenocarcinomas.

Results

HER2 mutations were detected in 29 of 572(5.1%) specimens from a selected population of EGFR/KRAS/BRAF/ALK/ROS1 negative patients. All of them are adenocarcinomas. Among patients with HER2-mutant lung cancers, 25 received pemetrexed-based first line chemotherapy. The objective response rate(ORR) was 36.0%. Their median progression free survival(PFS) was 5.1 months, which was similar with that of KRAS-mutant group (n = 40,5.0 months, p = 0.971), numerically shorter than that of EGFR-mutant group(n = 74, 6.5 months, p = 0.247) and statistically significantly shorter than that of ALK/ROS1-rearranged group (n = 39,9.2 months, p = 0.004). Furthermore, HER2 variants subgroup analysis showed that PFS was inferior in A775_G776insYVMA group compared with other variants (4.2 vs 7.2 months, p = 0.085).

Conclusions

Patients with advanced HER2-mutant lung adenocarcinomas showed an inferior outcome of first line pemetrexed-based chemotherapy compared to those with ALK/ROS1 rearrangements, which strengthen the need for effective HER2-targeted drugs in clinical practice.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4277-x) contains supplementary material, which is available to authorized users.

The long tail of molecular alterations in non-small cell lung cancer: a single-institution experience of next-generation sequencing in clinical molecular diagnostics

BACKGROUND

Molecular profiling of advanced non-small cell lung cancers (NSCLC) is essential to identify patients who may benefit from targeted treatments. In the last years, the number of potentially actionable molecular alterations has rapidly increased. Next-generation sequencing allows for the analysis of multiple genes simultaneously.

AIMS

To evaluate the feasibility and the throughput of next-generation sequencing in clinical molecular diagnostics of advanced NSCLC.

METHODS

A single-institution cohort of 535 non-squamous NSCLC was profiled using a next-generation sequencing panel targeting 22 actionable and cancer-related genes.

RESULTS

441 non-squamous NSCLC (82.4%) harboured at least one gene alteration, including 340 cases (63.6%) with clinically relevant molecular aberrations. Mutations have been detected in all but one gene (FGFR1) of the panel. Recurrent alterations were observed in KRAS, TP53, EGFR, STK11 and MET genes, whereas the remaining genes were mutated in <5% of the cases. Concurrent mutations were detected in 183 tumours (34.2%), mostly impairing KRAS or EGFR in association with TP53 alterations.

CONCLUSIONS

The study highlights the feasibility of targeted next-generation sequencing in clinical setting. The majority of NSCLC harboured mutations in clinically relevant genes, thus identifying patients who might benefit from different targeted therapies.

Updated Molecular Testing Guideline for the Selection of Lung Cancer Patients for Treatment With Targeted Tyrosine Kinase Inhibitors: Guideline From the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology

CONTEXT

- In 2013, an evidence-based guideline was published by the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology to set standards for the molecular analysis of lung cancers to guide treatment decisions with targeted inhibitors. New evidence has prompted an evaluation of additional laboratory technologies, targetable genes, patient populations, and tumor types for testing.

OBJECTIVE

- To systematically review and update the 2013 guideline to affirm its validity; to assess the evidence of new genetic discoveries, technologies, and therapies; and to issue an evidence-based update.

DESIGN

- The College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology convened an expert panel to develop an evidence-based guideline to help define the key questions and literature search terms, review abstracts and full articles, and draft recommendations.

RESULTS

- Eighteen new recommendations were drafted. The panel also updated 3 recommendations from the 2013 guideline.

CONCLUSIONS

- The 2013 guideline was largely reaffirmed with updated recommendations to allow testing of cytology samples, require improved assay sensitivity, and recommend against the use of immunohistochemistry for EGFR testing. Key new recommendations include ROS1 testing for all adenocarcinoma patients; the inclusion of additional genes ( ERBB2, MET, BRAF, KRAS, and RET) for laboratories that perform next-generation sequencing panels; immunohistochemistry as an alternative to fluorescence in situ hybridization for ALK and/or ROS1 testing; use of 5% sensitivity assays for EGFR T790M mutations in patients with secondary resistance to EGFR inhibitors; and the use of cell-free DNA to "rule in" targetable mutations when tissue is limited or hard to obtain.

Updated Molecular Testing Guideline for the Selection of Lung Cancer Patients for Treatment With Targeted Tyrosine Kinase Inhibitors: Guideline From the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology

CONTEXT

In 2013, an evidence-based guideline was published by the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology to set standards for the molecular analysis of lung cancers to guide treatment decisions with targeted inhibitors. New evidence has prompted an evaluation of additional laboratory technologies, targetable genes, patient populations, and tumor types for testing.

OBJECTIVE

To systematically review and update the 2013 guideline to affirm its validity; to assess the evidence of new genetic discoveries, technologies, and therapies; and to issue an evidence-based update.

DESIGN

The College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology convened an expert panel to develop an evidence-based guideline to help define the key questions and literature search terms, review abstracts and full articles, and draft recommendations.

RESULTS

Eighteen new recommendations were drafted. The panel also updated 3 recommendations from the 2013 guideline.

CONCLUSIONS

The 2013 guideline was largely reaffirmed with updated recommendations to allow testing of cytology samples, require improved assay sensitivity, and recommend against the use of immunohistochemistry for EGFR testing. Key new recommendations include ROS1 testing for all adenocarcinoma patients; the inclusion of additional genes (ERBB2, MET, BRAF, KRAS, and RET) for laboratories that perform next-generation sequencing panels; immunohistochemistry as an alternative to fluorescence in situ hybridization for ALK and/or ROS1 testing; use of 5% sensitivity assays for EGFR T790M mutations in patients with secondary resistance to EGFR inhibitors; and the use of cell-free DNA to "rule in" targetable mutations when tissue is limited or hard to obtain.

Updated Molecular Testing Guideline for the Selection of Lung Cancer Patients for Treatment With Targeted Tyrosine Kinase Inhibitors: Guideline From the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology

CONTEXT

In 2013, an evidence-based guideline was published by the College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology to set standards for the molecular analysis of lung cancers to guide treatment decisions with targeted inhibitors. New evidence has prompted an evaluation of additional laboratory technologies, targetable genes, patient populations, and tumor types for testing.

OBJECTIVE

To systematically review and update the 2013 guideline to affirm its validity; to assess the evidence of new genetic discoveries, technologies, and therapies; and to issue an evidence-based update.

DESIGN

The College of American Pathologists, the International Association for the Study of Lung Cancer, and the Association for Molecular Pathology convened an expert panel to develop an evidence-based guideline to help define the key questions and literature search terms, review abstracts and full articles, and draft recommendations.

RESULTS

Eighteen new recommendations were drafted. The panel also updated 3 recommendations from the 2013 guideline.

CONCLUSIONS

The 2013 guideline was largely reaffirmed with updated recommendations to allow testing of cytology samples, require improved assay sensitivity, and recommend against the use of immunohistochemistry for EGFR testing. Key new recommendations include ROS1 testing for all adenocarcinoma patients; the inclusion of additional genes (ERBB2, MET, BRAF, KRAS, and RET) for laboratories that perform next-generation sequencing panels; immunohistochemistry as an alternative to fluorescence in situ hybridization for ALK and/or ROS1 testing; use of 5% sensitivity assays for EGFR T790M mutations in patients with secondary resistance to EGFR inhibitors; and the use of cell-free DNA to "rule in" targetable mutations when tissue is limited or hard to obtain.

Standardizing biomarker testing for Canadian patients with advanced lung cancer

BACKGROUND

The development and approval of both targeted and immune therapies for patients with advanced non-small cell lung cancer (nsclc) has significantly improved patient survival rates and quality of life. Biomarker testing for patients newly diagnosed with nsclc, as well as for patients progressing after treatment with epidermal growth factor receptor (EGFR) inhibitors, is the standard of care in Canada and many parts of the world.

METHODS

A group of thoracic oncology experts in the field of thoracic oncology met to describe the standard for biomarker testing for lung cancer in the Canadian context, focusing on evidence-based recommendations for standard-of-care testing for EGFR, anaplastic lymphoma kinase (ALK), ROS1, BRAF V600 and programmed death-ligand (PD-L1) at the time of diagnosis of advanced disease and EGFR T790M upon progression. As well, additional exploratory molecules and targets are likely to impact future patient care, including MET exon 14 skipping mutations and whole gene amplification, RET translocations, HER2 (ERBB2) mutations, NTRK, RAS (KRAS and NRAS), as well as TP53.

RESULTS

The standard of care must include the incorporation of testing for novel biomarkers as they become available, as it will be difficult for national guidelines to keep pace with technological advances in this area.

CONCLUSIONS

Canadian patients with nsclc should be treated equally; the minimum standard of care is defined in this paper.

Efficacy of histology-agnostic and molecularly-driven HER2 inhibitors for refractory cancers

A targeted therapy is recommended in case of ERBB2 alteration for breast and gastric carcinomas, but miscellaneous other tumor types are ERBB2-altered at low prevalence. Broadening the administration of HER2 inhibitors across tumor types and genomic alterations could benefit to patients with refractory metastatic tumors.

Targeted next-generation-sequencing (tNGS) and comparative genomic hybridization array (CGH) have been performed on fresh tumor biopsies of patients included in the MOSCATO-01 and ongoing MOSCATO-02 trials to administrate HER2 inhibitors in case of ERBB2 pathogenic mutation of amplification.

Between December 2011 and January 2017 a molecular analysis was performed for 934 patients (759 CGH and 912 tNGS). A novel ERBB2 alteration has been found in 4.7% (n = 44/934), including 1.5% (n = 14/912) ERBB2 mutations, and 4% (n = 30/759) ERBB2 amplifications.

A matched HER2 inhibitor was administrated to 70% (31/44) of patients and consisted in trastuzumab plus chemotherapy for 90% of them (28/31). On the 31 evaluable patients, 1 complete response (CR), 10 partial response (PR) and 2 stable disease (SD) >24 weeks were observed accounting for a clinical benefit rate (CBR) of 42% (n = 13/31, 95% CI 25–61%). Besides breast and oesogastric carcinomas, 19 patients affected by 8 different tumor types had a CBR of 25% for ERBB2 mutations (n = 2/8, 95% CI 3%–65%, with 2 PR) and 64% for ERBB2 amplifications (n = 7/11, 95% CI 31%–89%; with 1 CR, 4 PR, 2 SD).

ERBB2 genomic alterations were diffuse across metastatic tumor types and signs of efficacy emerged for HER2 targeted treatments, especially in case of ERBB2 amplifications or a p.S310Y ERBB2 mutation.

Progress in the Management of Advanced Thoracic Malignancies in 2017

The treatment paradigm of NSCLC underwent a major revolution during the course of 2017. Immune checkpoint inhibitors (ICIs) brought remarkable improvements in response and overall survival both in unselected pretreated patients and in untreated patients with programmed death ligand 1 expression of 50% or more. Furthermore, compelling preliminary results were reported for new combinations of anti-programmed cell death 1/programmed death ligand 1 agents with chemotherapy or anti-cytotoxic T-lymphocyte associated protein 4 inhibitors. The success of the ICIs appeared to extend to patients with SCLC, mesothelioma, or thymic tumors. Furthermore, in SCLC, encouraging activity was reported for an experimental target therapy (rovalpituzumab teserine) and a new chemotherapeutic agent (lurbinectedin). For oncogene-addicted NSCLC, next-generation tyrosine kinase inhibitors (TKIs) (such as osimertinib or alectinib) have demonstrated increased response rates and progression-free survival compared with first-generation TKIs in patients with both EGFR-mutated and ALK receptor tyrosine kinase gene (ALK)-rearranged NSCLC. However, because of the lack of mature overall survival data and considering the high efficacy of these drugs in patients with NSCLC previously exposed to first- or second-generation TKIs, definitive conclusions concerning the best treatment sequence cannot yet be drawn. In addition, new oncogenes such as mutant BRAF, tyrosine-protein kinase met gene (MET) and erb-b2 receptor tyrosine kinase 2 gene (HER2), and ret proto-oncogene (RET) rearrangements have joined the list of potential targetable drivers. In conclusion, the field of thoracic oncology is on the verge of a breakthrough that will open up many promising new therapeutic options for physicians and patients. The characterization of biomarkers predictive of sensitivity or resistance to immunotherapy and the identification of the optimal therapeutic combinations (for ICIs) and treatment sequence (for oncogene-addicted NSCLC) represent the toughest upcoming challenges in the domain of thoracic oncology.

Targeting HER2 Aberrations in Non-Small Cell Lung Cancer with Osimertinib

Purpose:HER2 (or ERBB2) aberrations, including both amplification and mutations, have been classified as oncogenic drivers that contribute to 2% to 6% of lung adenocarcinomas. HER2 amplification is also an important mechanism for acquired resistance to EGFR tyrosine kinase inhibitors (TKI). However, due to limited preclinical studies and clinical trials, currently there is still no available standard of care for lung cancer patients with HER2 aberrations. To fulfill the clinical need for targeting HER2 in patients with non-small cell lung cancer (NSCLC), we performed a comprehensive preclinical study to evaluate the efficacy of a third-generation TKI, osimertinib (AZD9291).Experimental Design: Three genetically modified mouse models (GEMM) mimicking individual HER2 alterations in NSCLC were generated, and osimertinib was tested for its efficacy against these HER2 aberrations in vivoResults: Osimertinib treatment showed robust efficacy in HER2^wt overexpression and EGFR del19/HER2 models, but not in HER2 exon 20 insertion tumors. Interestingly, we further identified that combined treatment with osimertinib and the BET inhibitor JQ1 significantly increased the response rate in HER2-mutant NSCLC, whereas JQ1 single treatment did not show efficacy.Conclusions: Overall, our data indicated robust antitumor efficacy of osimertinib against multiple HER2 aberrations in lung cancer, either as a single agent or in combination with JQ1. Our study provides a strong rationale for future clinical trials using osimertinib either alone or in combination with epigenetic drugs to target aberrant HER2 in patients with NSCLC. Clin Cancer Res; 24(11); 2594-604. ©2018 AACRSee related commentary by Cappuzzo and Landi, p. 2470.

Efficacy of Afatinib in a Previously-Treated Patient with Non-Small Cell Lung Cancer Harboring HER2 Mutation: Case Report

Human epidermal growth factor receptor 2 (HER2) mutation in non-small cell lung cancer (NSCLC) is an oncogenic driver that possibly becomes a druggable target to HER2-targeted therapy. The benefit of HER2-targeted therapy is much less defined especially in eastern populations. We provide evidence of clinical benefit of afatinib in a 50-year-old Asian woman with HER2-mutant NSCLC who previously failed cytotoxic chemotherapy and gefitinib treatment. Next-generation sequencing of the tumor tissue revealed a HER2 exon 20 mutation (c.2437A>G), which has never been reported. The patient was treated with afatinib for more than four months. She showed rapid radiologic response within a month, and maintained stable state until the last dose of afatinib.

The Impact of Smoking and TP53 Mutations in Lung Adenocarcinoma Patients with Targetable Mutations-The Lung Cancer Mutation Consortium (LCMC2)

Purpose: Multiplex genomic profiling is standard of care for patients with advanced lung adenocarcinomas. The Lung Cancer Mutation Consortium (LCMC) is a multi-institutional effort to identify and treat oncogenic driver events in patients with lung adenocarcinomas.Experimental Design: Sixteen U.S. institutions enrolled 1,367 patients with lung cancer in LCMC2; 904 were deemed eligible and had at least one of 14 cancer-related genes profiled using validated methods including genotyping, massively parallel sequencing, and IHC.Results: The use of targeted therapies in patients with EGFR, ERBB2, or BRAF p.V600E mutations, ALK, ROS1, or RET rearrangements, or MET amplification was associated with a survival increment of 1.5 years compared with those with such mutations not receiving targeted therapy, and 1.0 year compared with those lacking a targetable driver. Importantly, 60 patients with a history of smoking derived similar survival benefit from targeted therapy for alterations in EGFR/ALK/ROS1, when compared with 75 never smokers with the same alterations. In addition, coexisting TP53 mutations were associated with shorter survival among patients with EGFR, ALK, or ROS1 alterations.Conclusion: Patients with adenocarcinoma of the lung and an oncogenic driver mutation treated with effective targeted therapy have a longer survival, regardless of prior smoking history. Molecular testing should be performed on all individuals with lung adenocarcinomas irrespective of clinical characteristics. Routine use of massively parallel sequencing enables detection of both targetable driver alterations and tumor suppressor gene and other alterations that have potential significance for therapy selection and as predictive markers for the efficacy of treatment. Clin Cancer Res; 24(5); 1038-47. ©2017 AACR.

Genomic alterations of ERBB receptors in cancer: clinical implications

The ERBB family of receptor tyrosine kinases has been implicated in carcinogenesis for over three decades with rigorous attention to EGFR and HER2. ERBB receptors, consisting of EGFR, HER2, HER3, and HER4 are part of a complicated signaling network that activates downstream signaling pathways including PI3K/AKT, Ras/Raf/MAPK, JAK/STAT and PKC. It is well established that EGFR is amplified and/or mutated in gliomas and non-small-cell lung carcinoma while HER2 is amplified and/or over-expressed in breast, gastric, ovarian, non-small cell lung carcinoma, and several other tumor types. With the advent of next generation sequencing and large scale efforts to explore the entire spectrum of genomic alterations involved in human cancer progression, it is now appreciated that somatic ERBB receptor mutations occur at relatively low frequencies across multiple tumor types. Some of these mutations may represent oncogenic driver events; clinical studies are underway to determine whether tumors harboring these alterations respond to small molecule EGFR/HER2 inhibitors. Recent evidence suggests that some somatic ERBB receptor mutations render resistance to FDA-approved EGFR and HER2 inhibitors. In this review, we focus on the landscape of genomic alterations of EGFR, HER2, HER3 and HER4 in cancer and the clinical implications for patients harboring these alterations.

Activating HER2 mutations as emerging targets in multiple solid cancers

The epidermal growth factor receptor (EGFR) family of transmembrane receptor tyrosine kinases activates signalling pathways regulating cellular proliferation and survival. HER2 is a non-ligand-binding member of this family and exerts its activity through heterodimerisation with other EGFR family members. HER2 functional activation promotes oncogenesis, leading to the investigation of HER2-directed agents in cancers with HER2 alterations. This has been best characterised in the context of HER2 gene amplification in breast and gastro-oesophageal cancers, for which HER2-directed drugs form part of standard treatment regimens. More recently, somatic HER2 gene mutations have been detected in a range of human cancer types. Preclinical data suggest that functionally activating HER2 mutations may drive and maintain cancers in a manner analogous to HER2 gene amplification and that HER2 mutations may similarly confer sensitivity to HER2-directed drugs. Here, we critically review the emerging roles for HER2-directed drugs in HER2 mutant cancers. We review data from experimental models, where our knowledge of the underlying biology of HER2 mutational activation remains incomplete. We discuss clinical data from Phase I and II clinical trials which evaluate HER2-directed agents (tyrosine kinase inhibitors and antibody-based drugs) in several cancer types. We highlight the heterogeneity of HER2 mutations in human cancers, differences in the clinical efficacy of HER2-directed drugs between cancer types and possible mechanisms of primary and acquired resistance, in order to guide clinical practice and future drug development.

Reduction in Hepatocyte Growth Factor Serum Levels is Associated with Improved Prognosis in Advanced Lung Adenocarcinoma Patients Treated with Afatinib: a Phase II Trial

BACKGROUND

C-met and its ligand, hepatocyte growth factor (HGF) have been associated with the resistance mechanism of EGFR-TKIs. HGF was evaluated as a clinical-marker of response in NSCLC patients treated with afatinib.

METHODS

Sixty-six patients with stage IIIB/IV lung adenocarcinoma and progression to any-line chemotherapy received afatinib 40 mg/day. Mutational EGFR and HER2 status were assessed by RT-PCR. HER2 amplification was evaluated by FISH. Serum HGF content was measured by ELISA before and 2 months after the start of treatment. HGF levels were assessed with the objective response rate (ORR), progression-free-survival (PFS), and overall survival (OS). This trial was registered on ClinicalTrials.gov: NCT01542437.

RESULTS

Fifty patients (75 %) were EGFR mutation positive. Response was achieved in 59 % of all patients and 78 % of EGFR mutated patients. Median PFS was 10 [95 % CI 6.8-13.1] and 14.5 months [10.9-18.9] for all and EGFR mutated patients, respectively. Median OS was 22.8 [17.5-28.1] and 32.4 months [18.3-46.6] for all and EGFR mutated patients, respectively. Patients with reduced serum HGF levels had improved ORR (75 % vs 44 %; p = 0.011), PFS (15.1 [2.9-27.3] vs 6.5 months [3.9-9.1]; p = 0.005) and OS (NR vs 14.5 months [7.8 - 21.3] p = 0.007). A reduction in serum HGF levels was an independent factor associated with longer PFS (HR 0.40; p = 0.021) and OS (HR 0.31; p = 0.006) in all and EGFR mutated patients.

CONCLUSIONS

A reduction in serum HGF levels was associated with improved outcomes in patients treated with afatinib. These results suggest HGF might have a role as a mechanism of resistance to EGFR-TKIs. HGF could represent a potential therapeutic target to prevent or reverse resistance particularly in EGFR mutated patients.

Mechanisms of resistance to irreversible epidermal growth factor receptor tyrosine kinase inhibitors and therapeutic strategies in non-small cell lung cancer

Epidermal growth factor receptor (EGFR) T790M mutation is the most frequent mechanism which accounts for about 60% of acquired resistance to first-generation EGFR tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC) patients harboring EGFR activating mutations. Irreversible EGFR-TKIs which include the second-generation and third-generation EGFR-TKIs are developed to overcome T790M mediated resistance. The second-generation EGFR-TKIs inhibit the wide type (WT) EGFR combined with dose-limiting toxicity which limits its application in clinics, while the development of third-generation EGFR-TKIs brings inspiring efficacy either in vitro or in vivo. The acquired resistance, however, will also occur and limit their response. Understanding the mechanisms of resistance to irreversible EGFR-TKIs plays an important role in the choice of subsequent treatment. In this review, we show the currently known mechanisms of resistance which can be summarized as EGFR dependent and independent mechanisms and potential therapeutic strategies to irreversible EGFR-TKIs.

Understanding and targeting resistance mechanisms in NSCLC

The expanding spectrum of both established and candidate oncogenic driver mutations identified in non-small-cell lung cancer (NSCLC), coupled with the increasing number of clinically available signal transduction pathway inhibitors targeting these driver mutations, offers a tremendous opportunity to enhance patient outcomes. Despite these molecular advances, advanced-stage NSCLC remains largely incurable due to therapeutic resistance. In this Review, we discuss alterations in the targeted oncogene ('on-target' resistance) and in other downstream and parallel pathways ('off-target' resistance) leading to resistance to targeted therapies in NSCLC, and we provide an overview of the current understanding of the bidirectional interactions with the tumour microenvironment that promote therapeutic resistance. We highlight common mechanistic themes underpinning resistance to targeted therapies that are shared by NSCLC subtypes, including those with oncogenic alterations in epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), ROS1 proto-oncogene receptor tyrosine kinase (ROS1), serine/threonine-protein kinase b-raf (BRAF) and other less established oncoproteins. Finally, we discuss how understanding these themes can inform therapeutic strategies, including combination therapy approaches, and overcome the challenge of tumour heterogeneity.

Comprehensive genomic profiling of lung cancer using a validated panel to explore therapeutic targets in East Asian patients

People of East Asian ethnicity have a different prevalence of and show unique clinical characteristics and tumor histology of oncogenic mutations. However, only limited studies have explored the landscape of genomic alterations in lung adenocarcinoma derived from Asian patients thus far. In this single‐center study, with an aim to elucidate the mutational profile of lung cancer in people of Chinese ethnicity and to use the obtained information to guide decision‐making for treatment, we employed a well‐validated assay to perform comprehensive genomic characterization of tumor specimens from 306 Chinese lung cancer patients. A total of 845 individual genomic alterations were found in 145 tumor‐related genes with a median of 2.8 alterations (range: 1–18) per sample. The most frequently mutated genes were EGFR (46.7%), TP53 (21.2%), ALK (12.1%; 8.8% of mutation and 3.3% of rearrangement) and KRAS (10.1%). Upon comparison with the Cancer Genome Atlas dataset, we found that EGFR was mutated at a much higher frequency in our cohort than in Caucasians, whereas KRAS was only found in 10.1% of our Chinese patients. Clinically relevant genomic alterations were identified in 185 (60.5%) patients, including 50% in adenocarcinoma patients and 14% in squamous cell carcinoma patients. Our findings suggest that the Asian ethnicity is significantly different from the Caucasian ethnicity with regard to the presence of somatic driver mutations. Furthermore, we showed that the use of a comprehensive genotyping approach could help identify actionable genomic alterations that have potential impact on therapeutic decisions.

Targeting Novel but Less Common Driver Mutations and Chromosomal Translocations in Advanced Non-Small Cell Lung Cancer

Discovery of the epidermal growth factor receptor gene mutation and the anaplastic lymphoma kinase chromosomal translocation in non-small cell lung cancer has prompted efforts around the world to identify many less common targetable oncogenic drivers. Such concerted efforts have been variably successful in both non-squamous and squamous cell carcinomas of the lung. Some of the targeted therapies for these oncogenic drivers have received regulatory approval for clinical use, while others have modest clinical benefit. In this mini-review, several of these targets will be reviewed.

Expanded molecular interrogation for potential actionable targets in non-squamous non-small cell lung cancer

The advent of targeted therapies has established new standards of care for defined molecular subsets of non-small cell lung cancer (NSCLC). Not only has this led to significant changes in the routine clinical management of lung cancer e.g., multiplexed genomic testing, but it has provided important principles and benchmarks for determining "actionability". At present, the clinical paradigms are most evolved for EGFR mutations and ALK rearrangements, where multiple randomized phase III trials have determined optimal treatment strategies in both treatment naïve and resistant settings. However, this may not always be feasible with low prevalence alterations e.g., ROS1 and BRAF mutations. Another emerging observation is that not all targets are equally "actionable", necessitating a rigorous preclinical, clinical and translational framework to prosecute new targets and drug candidates. In this review, we will cover the role of targeted therapies for NSCLC harbouring BRAF, MET, HER2 and RET alterations, all of which have shown promise in non-squamous non-small cell lung cancer (ns-NSCLC). We further review some early epigenetic targets in NSCLC, an area of emerging interest. With increased molecular segmentation of lung cancer, we discuss the upcoming challenges in drug development and implementation of precision oncology approaches, especially in light of the complex and rapidly evolving therapeutic landscape.

An update on biomarkers for kinase inhibitor response in non-small-cell lung cancer

INTRODUCTION

The discovery of activating genetic and their use as predictive biomarkers for targeted therapy, such as tyrosine kinase inhibitors (TKIs), has changed the treatment paradigm of non-small cell lung cancer (NSCLC). As a result, epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK) TKIs have become the standard first-line treatment. Since then, other kinds of targetable oncogenic alterations have been identified in NSCLC. Several novel, molecularly-targeted TKIs have now achieved regulatory approval, while many others are currently in early- or late-phase clinical trial testing. These TKIs have significantly impacted and changed clinical outcomes for advanced NSCLC. Areas covered: In this review, the authors discuss recent evidence and progress in targeted therapies, especially small molecular tyrosine kinase inhibitors, matched with their biomarkers for the treatment of advanced NSCLC. Expert commentary: Although targeted therapies dramatically improve the outcome of patients with NSCLC harboring specific oncogenic alterations, molecular and clinical resistance almost invariably develops. New TKIs specifically active in molecular subgroups of NSCLC or the resistance setting have now been developed. The development of additional TKIs and rational combinations may further improve outcomes of NSCLC.

Scientific Advances in Thoracic Oncology 2016

Lung cancer care is rapidly changing with advances in genomic testing, the development of next-generation targeted kinase inhibitors, and the continued broad study of immunotherapy in new settings and potential combinations. The International Association for the Study of Lung Cancer and the Journal of Thoracic Oncology publish this annual update to help readers keep pace with these important developments. Experts in thoracic cancer and care provide focused updates across multiple areas, including prevention and early detection, molecular diagnostics, pathology and staging, surgery, adjuvant therapy, radiotherapy, molecular targeted therapy, and immunotherapy for NSCLC, SCLC, and mesothelioma. Quality and value of care and perspectives on the future of lung cancer research and treatment have also been included in this concise review.

Impact of somatic PI3K pathway and ERBB family mutations on pathological complete response (pCR) in HER2-positive breast cancer patients who received neoadjuvant HER2-targeted therapies

Background

The Cancer Genome Atlas analysis revealed that somatic EGFR, receptor tyrosine-protein kinase erbB-2 (ERBB2), Erb-B2 receptor tyrosine kinase 3 (ERBB3) and Erb-B2 receptor tyrosine kinase 4 (ERBB4) gene mutations (ERBB family mutations) occur alone or co-occur with somatic mutations in the gene encoding the phosphatidylinositol 3-kinase (PI3K) catalytic subunit (PIK3CA) in 19% of human epidermal growth factor receptor 2 (HER2)-positive breast cancers. Because ERBB family mutations can activate the PI3K/AKT pathway and likely have similar canonical signalling effects to PI3K pathway mutations, we investigated their combined impact on response to neoadjuvant HER2-targeted therapies.

Methods

Baseline tumour biopsies were available from 74 patients with HER2-positive breast cancer who were enrolled in the phase II TCHL neoadjuvant study (ICORG 10-05) assessing TCH (docetaxel, carboplatin, trastuzumab) (n = 38) versus TCL (docetaxel, carboplatin, lapatinib) (n = 10) versus TCHL (docetaxel, carboplatin, trastuzumab, lapatinib) (n = 40), each for six cycles. Activating mutations in PIK3CA and ERBB family genes were identified using mass spectrometry-based genotyping. Phosphatase and tensin homolog (PTEN) expression was assessed by immunohistochemistry.

Results

PIK3CA and/or ERBB family mutations were detected in 23 (31.1%) tumour samples tested, whereas PTEN expression was low in 31.1% of cases tested. Mutation frequency was similar in each treatment arm (31.3% in TCH arm, 30% in TCL arm and 31.3% in TCHL arm) and was not influenced by oestrogen receptor (ER) status (27.6% in ER-negative patients, 33.3% in ER-positive patients) or progesterone receptor (PR) status (32.6% in PR-negative patients, 29% in PR-positive patients). There was no significant difference in pathological complete response (pCR) rates between 47 patients with wild-type (WT) tumours and 22 patients whose tumours carried mutations (in either PIK3CA or ERBB family genes) (42.5% vs. 54.5%; p = 0.439). Similarly, there was no significant difference in pCR rates between patients with PIK3CA/ERBB family mutated/PTEN-low (i.e., PI3K-activated) tumours and patients without PI3K activation (50% vs. 44%; p = 0.769). However, in the TCHL (but not the TCH) group, the pCR rate was higher for 9 patients with PIK3CA/ERBB family mutated tumours than for 20 patients with PIK3CA/ERBB family WT tumours (77.8% vs. 35%; p = 0.05).

Conclusions

Our results indicate that patients who receive neoadjuvant TCHL and have PIK3CA/ERBB family mutated tumours may be more likely to have a pCR than patients with WT tumours.

Trial registration

ClinicalTrials.gov, NCT01485926. Registered on 2 December 2011.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-017-0883-9) contains supplementary material, which is available to authorized users.

HER2 mutations in lung adenocarcinomas: A report from the Lung Cancer Mutation Consortium

BACKGROUND

Human epidermal growth factor receptor 2 (HER2) mutations have been reported in lung adenocarcinomas. Herein, the authors describe the prevalence, clinical features, and outcomes associated with HER2 mutations in 1007 patients in the Lung Cancer Mutation Consortium (LCMC).

METHODS

Patients with advanced-stage lung adenocarcinomas were enrolled to the LCMC. Tumor specimens were assessed for diagnosis and adequacy; multiplexed genotyping was performed in Clinical Laboratory Improvement Amendments (CLIA)-certified laboratories to examine 10 oncogenic drivers. The LCMC database was queried for patients with HER2 mutations to access demographic data, treatment history, and vital status. An exploratory analysis was performed to evaluate the survival of patients with HER2 mutations who were treated with HER2-directed therapies.

RESULTS

A total of 920 patients were tested for HER2 mutations; 24 patients (3%) harbored exon 20 insertion mutations (95% confidence interval, 2%-4%). One patient had a concurrent mesenchymal-epithelial transition factor (MET) amplification. The median age of the patients was 62 years, with a slight predominance of females over males (14 females vs 10 males). The majority of the patients were never-smokers (71%) and presented with advanced disease at the time of diagnosis. The median survival for patients who received HER2-targeted therapies (12 patients) was 2.1 years compared with 1.4 years for those who did not (12 patients) (P = .48). Patients with HER2 mutations were found to have inferior survival compared with the rest of the LCMC cohort with other mutations: the median survival was 3.5 years in the LCMC population receiving targeted therapy and 2.4 years for patients not receiving targeted therapy.

CONCLUSIONS

HER2 mutations were detected in 3% of patients with lung adenocarcinoma in the LCMC. HER2-directed therapies should be investigated in this subgroup of patients. Cancer 2017;123:4099-4105. © 2017 American Cancer Society.

Lung cancer as a paradigm for precision oncology in solid tumours

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related death in the western world. However, the combination of molecular genotyping and subsequent systematic treatment of decoded target structures is a prime example of precision oncology in solid tumours. In this review, current targets of approved therapeutics and potential targets in clinical and preclinical trials are outlined. Furthermore, immune checkpoint inhibitors, as promising new therapeutic options, which have already been applied successfully in cases of lung cancer, are introduced. A major issue of targeted treatment of lung tumours is the persistent development of resistance. The underlying mechanisms and established and potentially applicable alternative therapeutic approaches are described. In this process of precision oncology, immunohistochemistry, fluorescence in situ hybridization, and parallel sequencing are crucial diagnostic tools.

Prognostic impact of TTF-1 expression in patients with stage IV lung adenocarcinomas

OBJECTIVES

Thyroid transcription factor 1 (TTF-1) is routinely tested in the diagnostic evaluation of suspected lung cancers, is commonly expressed by lung adenocarcinomas, and may modulate lung cancer biology. We examined the role of TTF-1 as a predictive and prognostic marker in patients with advanced lung adenocarcinomas.

MATERIALS AND METHODS

We analyzed clinical, pathologic, and molecular features, treatments received, and overall survival obtained from the medical records of 479 consecutive patients at a single site with stage IV lung adenocarcinomas and evaluable TTF-1 expression. TTF-1 expression was determined by immunohistochemistry using antibody 8G7G3/1.

RESULTS AND CONCLUSION

TTF-1 expression was evaluable in 479 (75%) of all patients reviewed, and was positive in 383 (80%, 95% CI 76-83%). Clinicopathologic features were similar between TTF-1 positive and TTF-1 negative tumors, except EGFR mutations were more common in TTF-1 positive cases (24% vs 6%, p<0.001). In univariate analysis, overall survival was significantly longer in patients with TTF-1 positive versus TTF-1 negative tumors (18 months vs 9 months, p<0.0001). In multivariate analysis, TTF-1 positivity remained associated with better overall survival (HR=0.38, p<0.0001), exceeding the prognostic impact of Karnofsky performance status >/=80% (HR 0.62, p=0.0003) and receipt of first-line combination chemotherapy or targeted therapy (HR relative to first-line single agent chemotherapy 0.59, p=0.05 and 0.51, p=0.05 respectively). Both patients with TTF-1 positive and TTF-1 negative cancers had longer durations of initial therapy when treated with pemetrexed-based chemotherapy. In patients with advanced lung adenocarcinomas, TTF-1 expression is associated with better survival but is not predictive of distinct benefit from pemetrexed-based chemotherapy.

Imprecision in the Era of Precision Medicine in Non-Small Cell Lung Cancer

Over the past decade, major advances have been made in the management of advanced non-small cell lung cancer (NSCLC). There has been a particular focus on the identification and targeting of putative driver aberrations, which has propelled NSCLC to the forefront of precision medicine. Several novel molecularly targeted agents have now achieved regulatory approval, while many others are currently in late-phase clinical trial testing. These antitumor therapies have significantly impacted the clinical outcomes of advanced NSCLC and provided patients with much hope for the future. Despite this, multiple deficiencies still exist in our knowledge of this complex disease, and further research is urgently required to overcome these critical issues. This review traces the path undertaken by the different therapeutics assessed in NSCLC and the impact of precision medicine in this disease. We also discuss the areas of "imprecision" that still exist in NSCLC and the modern hypothesis-testing studies being conducted to address these key challenges.

Second-line Treatment of Non-Small Cell Lung Cancer: Focus on the Clinical Development of Dacomitinib

Dacomitinib is a second-generation, irreversible, covalent pan-HER tyrosine-kinase inhibitor (TKI). It showed potent EGFR signaling inhibition in experimental models, including first-generation TKI-resistant non-small cell lung cancer (NSCLC) cell lines. This preclinical efficacy did not translate into clinically meaningful treatment benefits for advanced, pretreated, molecularly unselected NSCLC patients enrolled in two parallel phase III trials. Dacomitinib and erlotinib showed overlapping efficacy data in chemotherapy-pretreated EGFR wild-type (WT) patients in the ARCHER 1009 trial. Similarly, it failed to demonstrate any survival benefits as compared to placebo in EGFR WT subsets progressing on chemotherapy and at least one previous first-generation TKI (erlotinib or gefitinib) in the BR.26 trial. In the case of EGFR-mutant NSCLCs, a pooled analysis of the ARCHER 1009 and ARCHER 1028 trials comparing the efficacy of dacomitinib vs. erlotinib in chemotherapy-pretreated, EGFR TKI-naïve patients showed a trend to a longer progression-free survival (PFS) and overall survival in favor of dacomitinib that did not reach statistical significance, with a higher rate of treatment related adverse events (mainly skin rash, paronychia, and gastrointestinal toxicities). On the other hand, the clinical activity in patients with EGFR-mutant NSCLCs with acquired TKI resistance that were included in phase II/III trials was equally poor (response rate <10%; PFS 3-4 months). Therefore, with the results of the ARCHER 1050 trial (NCT01774721) still pending, the current clinical development of dacomitinib is largely focused on EGFR-mutant, TKI-naïve patients. Here, we review the most relevant clinical data of dacomitinib in advanced NSCLC. We discuss the potential role of dacomitinib in pretreated EGFR WT and EGFR-mutant (TKI-naïve and TKI-resistant) patients. Finally, we briefly comment the available clinical data of dacomitinib in HER2-mutant NSCLC patients.

Molecular biomarkers for lung adenocarcinoma

The identification of oncogenic driver alterations that underlie sensitivity to small inhibitors has led to growing interest in identifying additional targetable oncogenes in nonsmall cell lung cancer. Although the therapeutic impact of the discovery of these alterations has now been widely demonstrated, the epidemiological data associated with each of these biomarkers remain insufficiently studied. In this review, we discuss the techniques used to discover each of these candidate oncogenes, their prevalence in nonsmall cell lung cancer, and briefly outline the epidemiological features of the major oncogenes and ways in which their identification can determine therapeutic strategies.

Response Heterogeneity of EGFR and HER2 Exon 20 Insertions to Covalent EGFR and HER2 Inhibitors

Insertion mutations in EGFR and HER2 both occur at analogous positions in exon 20. Non-small cell lung cancer (NSCLC) patients with tumors harboring these mutations seldom achieve clinical responses to dacomitinib and afatinib, two covalent quinazoline-based inhibitors of EGFR or HER2, respectively. In this study, we investigated the effects of specific EGFR and HER2 exon 20 insertion mutations from NSCLC patients that had clinically achieved a partial response after dacomitinib treatment. We identified Gly770 as a common feature among the drug-sensitive mutations. Structural modeling suggested that this mutation may facilitate inhibitor binding to EGFR. Introduction of Gly770 into two dacomitinib-resistant EGFR exon 20 insertion mutants restored sensitivity to dacomitinib. Based on these findings, we used afatinib to treat an NSCLC patient whose tumor harbored the HER2 V777_G778insGSP mutation and achieved a durable partial response. We further identified secondary mutations in EGFR (T790M or C797S) and HER2 (C805S) that mediated acquired drug resistance in drug-sensitive EGFR or HER2 exon 20 insertion models. Overall, our findings identified a subset of EGFR and HER2 exon 20 insertion mutations that are sensitive to existing covalent quinazoline-based EGFR/HER2 inhibitors, with implications for current clinical treatment and next-generation small-molecule inhibitors. Cancer Res; 77(10); 2712-21. ©2017 AACR.

Prospective Comprehensive Molecular Characterization of Lung Adenocarcinomas for Efficient Patient Matching to Approved and Emerging Therapies

Tumor genetic testing is standard of care for patients with advanced lung adenocarcinoma, but the fraction of patients who derive clinical benefit remains undefined. Here, we report the experience of 860 patients with metastatic lung adenocarcinoma analyzed prospectively for mutations in >300 cancer-associated genes. Potentially actionable genetic events were stratified into one of four levels based upon published clinical or laboratory evidence that the mutation in question confers increased sensitivity to standard or investigational therapies. Overall, 37.1% (319/860) of patients received a matched therapy guided by their tumor molecular profile. Excluding alterations associated with standard-of-care therapy, 14.4% (69/478) received matched therapy, with a clinical benefit of 52%. Use of matched therapy was strongly influenced by the level of preexistent clinical evidence that the mutation identified predicts for drug response. Analysis of genes mutated significantly more often in tumors without known actionable mutations nominated STK11 and KEAP1 as possible targetable mitogenic drivers.Significance: An increasing number of therapies that target molecular alterations required for tumor maintenance and progression have demonstrated clinical activity in patients with lung adenocarcinoma. The data reported here suggest that broader, early testing for molecular alterations that have not yet been recognized as standard-of-care predictive biomarkers of drug response could accelerate the development of targeted agents for rare mutational events and could result in improved clinical outcomes. Cancer Discov; 7(6); 596-609. ©2017 AACR.See related commentary by Liu et al., p. 555This article is highlighted in the In This Issue feature, p. 539.

Biological therapies in nonsmall cell lung cancer

Biological therapies have improved survival outcomes of advanced-stage nonsmall cell lung cancer (NSCLC). Genotype-directed therapies have changed treatment paradigms of patients with EGFR-mutant and ALK/ROS1-rearranged lung adenocarcinomas, and the list of druggable targets with demonstrated clinical actionability (BRAF, MET, RET, NTRK1 and HER2) continues to expand. Furthermore, we have incrementally understood the mechanisms of cancer immune evasion and foresee ways to effectively circumvent them, particularly at the immune checkpoint level. Drugs targeting the tumour immune-evasive PD-1 pathway have demonstrated remarkable treatment benefits in this disease, with a non-negligible fraction of patients potentially receiving long-term survival benefits. Herein, we briefly discuss the role of various medical disciplines in the management of advanced-stage NSCLC and review the most relevant biological therapies for this disease, with particular emphasis in genotype-directed therapies and immune checkpoint inhibitors.

Comparable clinical outcomes in patients with HER2-mutant and EGFR-mutant lung adenocarcinomas

HER2 is a major proliferative driver in lung cancer. HER2 gene aberrations impact the prognosis of lung adenocarcinoma (ADC). A one-step reverse transcription-polymerase chain reaction was performed using RNA samples from 888 Asian lung cancer patients to detect HER2, EGFR, KRAS, ALK, and ROS1 mutations. The demographic data and treatment outcomes of HER2 mutation-positive lung ADC patients were analyzed and compared to those with HER2 mutation-negative tumors. HER2 mutation was identified in 40 (4.5%) lung ADC patients. HER2 mutations tended to occur in male patients with advanced-stage disease and never-smokers. A775_G776insYVMA (n = 22, 55%) was the most prevalent HER2 mutation, followed by P780_Y781insGSP (n = 4, 10%). For patients diagnosed with stage-IIIB/IV disease, HER2-mutant patients showed clinical outcomes comparable to EGFR-mutant patients (P = 0.721, log-rank test) and a better overall survival (OS) compared to patients lacking driver mutations in the investigated genes (P = 0.033, Breslow test). Specifically, lung ADC patients with stage-IV HER2-mutant tumors treated with chemotherapy or targeted agents, even without afatinib or anti-HER2 targeted therapy, showed similar clinical outcomes to lung ADC patients harboring EGFR exon 19 deletion or L858R mutations (P = 0.870). In addition, multivariate analysis indicated that HER2 mutation status was not a major risk factor for diminished OS in stage-IV lung cancer. In conclusion, lung ADC harboring HER2 mutations showed distinct characteristics from other driver mutations, including increased chemosensitivity with in advanced stage disease.

ERBB2-Mutated Metastatic Non-Small Cell Lung Cancer: Response and Resistance to Targeted Therapies

INTRODUCTION

Erb-b2 receptor tyrosine kinase 2 gene (ERBB2) (also called HER2) has long been recognized as an oncogenic driver in some breast and gastroesophageal cancers in which amplification of this gene confers sensitivity to treatment with Erb-b2 receptor tyrosine kinase 2 (ERBB2)-directed agents. More recently, somatic mutations in ERBB2 have been reported in 1% to 2% of patients with lung adenocarcinoma. Previous case series have suggested clinical tumor responses using anti-ERBB2 small molecules and antibody therapies.

METHODS

Here we report the outcomes of nine patients with metastatic lung adenocarcinoma with ERBB2 mutations being treated with ERBB2-targeted therapies.

RESULTS

Four of the nine patients had response to targeted therapies, with durations of response ranging from 3 to 10 months. We identified a de novo phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha gene (PIK3CA) mutation and ERBB2 copy number gain as potential resistance mechanisms.

CONCLUSIONS

We showed patients with ERBB2-mutated lung adenocarcinoma can respond to targeted therapies, and we identified potential resistance mechanisms upon progression to targeted therapies.

Lung cancer: current therapies and new targeted treatments

Lung cancer is the most frequent cause of cancer-related deaths worldwide. Every year, 1·8 million people are diagnosed with lung cancer, and 1·6 million people die as a result of the disease. 5-year survival rates vary from 4-17% depending on stage and regional differences. In this Seminar, we discuss existing treatment for patients with lung cancer and the promise of precision medicine, with special emphasis on new targeted therapies. Some subgroups, eg-patients with poor performance status and elderly patients-are not specifically addressed, because these groups require special treatment considerations and no frameworks have been established in terms of new targeted therapies. We discuss prevention and early detection of lung cancer with an emphasis on lung cancer screening. Although we acknowledge the importance of smoking prevention and cessation, this is a large topic beyond the scope of this Seminar.

Long lasting MDM2/Translocator protein modulator: a new strategy for irreversible apoptosis of human glioblastoma cells

The development of multi-target drugs and irreversible modulators of deregulated signalling proteins is the major challenge for improving glioblastoma multiforme (GBM) treatment. Reversible single-target drugs are not sufficient to sustain a therapeutic effect over time and may favour the activation of alternative signalling pathways and the onset of resistance phenomena. Thus, a multi-target compound that has a long-lasting mechanism of action might have a greater and longer life span of anti-proliferative activity. Recently, a dual-target indol-3ylglyoxyldipeptide derivative, designed to bind to the Translocator Protein (TSPO) and reactivate p53 function via dissociation from its physiological inhibitor, murine double minute 2 (MDM2), has been developed as a potent GBM pro-apoptotic agent. In this study, this derivative was chemically modified to irreversibly bind MDM2 and TSPO. The new compound elicited a TSPO-mediated mitochondrial membrane dissipation and restored p53 activity, triggering a long-lasting apoptosis of GBM cells. These effects were sustained over time, involved a stable activation of extracellular signal regulated kinases and were specifically observed in cancer cells, in which these protein kinases are deregulated. Dual-targeting and irreversible binding properties combined in the same molecule may represent a useful strategy to overcome the time-limited effects elicited by classical chemotherapies.

Cabozantinib in patients with advanced RET-rearranged non-small-cell lung cancer: an open-label, single-centre, phase 2, single-arm trial

BACKGROUND

RET rearrangements are found in 1-2% of non-small-cell lung cancers. Cabozantinib is a multikinase inhibitor with activity against RET that produced a 10% overall response in unselected patients with lung cancers. To assess the activity of cabozantinib in patients with RET-rearranged lung cancers, we did a prospective phase 2 trial in this molecular subgroup.

METHODS

We enrolled patients in this open-label, Simon two-stage, single-centre, phase 2, single-arm trial in the USA if they met the following criteria: metastatic or unresectable lung cancer harbouring a RET rearrangement, Karnofsky performance status higher than 70, and measurable disease. Patients were given 60 mg of cabozantinib orally per day. The primary objective was to determine the overall response (Response Criteria Evaluation in Solid Tumors version 1.1) in assessable patients; those who received at least one dose of cabozantinib, and had been given CT imaging at baseline and at least one protocol-specified follow-up timepoint. We did safety analyses in the modified intention-to-treat population who received at least one dose of cabozantinib. The accrual of patients with RET-rearranged lung cancer to this protocol has been completed but the trial is still ongoing because several patients remain on active treatment. This study was registered with ClinicalTrials.gov, number NCT01639508.

FINDINGS

Between July 13, 2012, and April 30, 2016, 26 patients with RET-rearranged lung adenocarcinomas were enrolled and given cabozantinib; 25 patients were assessable for a response. KIF5B-RET was the predominant fusion type identified in 16 (62%) patients. The study met its primary endpoint, with confirmed partial responses seen in seven of 25 response-assessable patients (overall response 28%, 95% CI 12-49). Of the 26 patients given cabozantinib, the most common grade 3 treatment-related adverse events were lipase elevation in four (15%) patients, increased alanine aminotransferase in two (8%) patients, increased aspartate aminotransferase in two (8%) patients, decreased platelet count in two (8%) patients, and hypophosphataemia in two (8%) patients. No drug-related deaths were recorded but 16 (62%) patients died during the course of follow-up. 19 (73%) patients required dose reductions due to drug-related adverse events.

INTERPRETATION

The reported activity of cabozantinib in patients with RET-rearranged lung cancers defines RET rearrangements as actionable drivers in patients with lung cancers. An improved understanding of tumour biology and novel therapeutic approaches will be needed to improve outcomes with RET-directed targeted treatment.

FUNDING

Exelixis, National Institutes of Health and National Cancer Institute Cancer Center Support Grant P30 CA008748.

New and emerging targeted treatments in advanced non-small-cell lung cancer

Targeted therapies are substantially changing the management of lung cancers. These treatments include drugs that target driver mutations, those that target presumed important molecules in cancer cell proliferation and survival, and those that inhibit immune checkpoint molecules. This area of research progresses day by day, with novel target discoveries, novel drug development, and use of novel combination treatments. Researchers and clinicians have also extensively investigated the predictive biomarkers and the molecular mechanisms underlying inherent or acquired resistance to these targeted therapies. We review recent progress in the development of targeted treatments for patients with advanced non-small-cell lung cancer, especially focusing on data from published clinical trials.

Outcomes of chemotherapies and HER2 directed therapies in advanced HER2-mutant lung cancers

Human epidermal growth factor receptor 2 (HER2, ERBB2) mutations occur in 3% of lung adenocarcinomas. While case reports and series have shown activity of HER2 targeted agents in these patients, little is known about outcomes of chemotherapies. Patients with stage IV HER2-mutant lung cancers at Memorial Sloan Kettering were reviewed. Patient demographics, types of HER2 mutations, duration of systemic treatments and survival were analyzed. We identified 38 patients with HER2-mutant lung cancers: median age 62; majority were women (n=24), never smokers (n=22), and all had adenocarcinomas. A 12 base pair in-frame insertion YVMA in exon 20 (p.A775_G776insYVMA) was present in 24 (63%, 95% CI 46-78%) patients. In addition, there were four 9 base pair insertions, one 6 base pair insertion, and five 3 base pair insertions in exon 20, and four single bp substitutions (exon 20 L755F, V777L, D769H, exon 8 S310F). The median overall survival from date of diagnosis of stage IV disease was 2.3 years (95% CI 1.2-2.6). The median duration of chemotherapy was 4.3 months (68 treatments, range 0-21 months): 6.2 months for pemetrexed ±platinum/bevacizumab, 4 months for taxane ±platinum/bevacizumab, 2.6 months for gemcitabine, 3.5 months for vinorelbine. The median duration of HER2 tyrosine kinase inhibitors was 2.2 months (28 treatments, range 0.3-16.3 months). As we search for better targeted therapies for patients with HER2-mutant lung cancers, chemotherapy remains an important component of care.

Alterations in genes other than EGFR/ALK/ROS1 in non-small cell lung cancer: trials and treatment options

During the last decade, we have seen tremendous progress in the therapy of lung cancer. Discovery of actionable mutations in EGFR and translocations in ALK and ROS1 have identified subsets of patients with excellent tumor response to oral targeted agents with manageable side effects. In this review, we highlight treatment options including corresponding clinical trials for oncogenic alterations affecting the receptor tyrosine kinases MET, FGFR, NTRK, RET, HER2, HER3, and HER4 as well as components of the RAS-RAF-MEK signaling pathway.

Recent Advances in Targetable Therapeutics in Metastatic Non-Squamous NSCLC

Lung adenocarcinoma is the most common subtype of non-small cell lung cancer (NSCLC). With the discovery of epidermal growth factor receptor (EGFR) mutations, anaplastic lymphoma kinase (ALK) rearrangements, and effective targeted therapies, therapeutic options are expanding for patients with lung adenocarcinoma. Here, we review novel therapies in non-squamous NSCLC, which are directed against oncogenic targets, including EGFR, ALK, ROS1, BRAF, MET, human epidermal growth factor receptor 2 (HER2), vascular endothelial growth factor receptor 2 (VEGFR2), RET, and NTRK. With the rapidly evolving molecular testing and development of new targeted agents, our ability to further personalize therapy in non-squamous NSCLC is rapidly expanding.

Pulse Afatinib for ERBB2 Exon 20 Insertion-Mutated Lung Adenocarcinomas

INTRODUCTION

Genomic aberrations involving the erb-b2 receptor tyrosine kinase 2 gene (ERBB2) are driver oncogenes in approximately 2% of lung adenocarcinomas. However, the use of daily dosing of ERBB2 tyrosine kinase inhibitors (TKIs)-including afatinib-has been fraught with plasma concentrations that barely achieve preclinical model inhibition, significant patient-reported toxicities, and limited clinical activity. We hypothesized that alternative dosing strategies could improve tolerability and efficacy.

METHODS

We profiled lung cancer cell lines against TKIs and retrospectively evaluated the toxicity of and response to pulse afatinib (280 mg once weekly) in lung cancers with ERBB2 mutations.

RESULTS

An ERBB2 exon 20 insertion-mutated lung cancer cell line had a 50% inhibitory concentration in response to afatinib that was higher than the reported plasma concentration of afatinib, 40 mg daily. Three patients with advanced ERBB2-mutated lung adenocarcinomas were treated with off-label pulse afatinib. The 280-mg weekly dose was well tolerated with no reported rash and minimal diarrhea. One TKI-naive patient achieved a partial response for 5 months and another achieved stable disease for 11 months.

CONCLUSIONS

Pulse afatinib at a weekly dosing scheme induced antitumor activity in ERBB2 exon 20 insertion-mutated lung adenocarcinomas. Future clinical trials of alternative dosing schemes of ERBB TKIs as monotherapy or in combination with other therapies are warranted for ERBB2-mutated tumors.