Summary Lung cancer is the most common cause of cancer deaths worldwide. The two broad histological subtypes of lung cancer are small-cell lung cancer (SCLC), which is the cause of 15% of cases, and ...non-small-cell lung cancer (NSCLC), which accounts for 85% of cases and includes adenocarcinoma, squamous-cell carcinoma, and large-cell carcinoma. Although NSCLC and SCLC are commonly thought to be different diseases owing to their distinct biology and genomic abnormalities, the idea that these malignant disorders might share common cells of origin has been gaining support. This idea has been supported by the unexpected findings that a subset of NSCLCs with mutated EGFR return as SCLC when resistance to EGFR tyrosine kinase inhibitors develops. Additionally, other case reports have described the coexistence of NSCLC and SCLC, further challenging the commonly accepted view of their distinct lineages. Here, we summarise the published clinical observations and biology underlying tumours with combined SCLC and NSCLC histology and cancers that transform from adenocarcinoma to SCLC. We also discuss pre-clinical studies pointing to common potential cells of origin, and speculate how the distinct paths of differentiation are determined by the genomics of each disease.
The use of advanced molecular profiling to direct the use of targeted therapy, such as tyrosine kinase inhibitors (TKIs) for patients with advanced-stage non-small-cell lung cancer (NSCLC), has ...revolutionized the treatment of this disease. However, acquired resistance, defined as progression after initial benefit, to targeted therapies inevitably occurs. This Review explores breakthroughs in the understanding and treatment of acquired resistance in NSCLC, focusing on EGFR mutant and ALK rearrangement-positive disease, which may be relevant across multiple different solid malignancies with oncogene-addicted subtypes. Mechanisms of acquired resistance may be pharmacological (that is, failure of delivery of the drug to its target) or biological, resulting from evolutionary selection on molecularly diverse tumours. A number of clinical approaches can maintain control of the disease in the acquired resistance setting, including the use of radiation to treat isolated areas of progression and adding or switching to cytotoxic chemotherapy. Furthermore, novel approaches that have already proven successful include the development of second-generation and third-generation inhibitors and the combination of some of these inhibitors with antibodies directed against the same target. With our increased understanding of the spectrum of acquired resistance, major changes in how we conduct clinical research in this setting are now underway.
Purpose In two phase III studies, nivolumab, a programmed death-1 (PD-1) inhibitor antibody, improved overall survival (OS) versus docetaxel in pretreated advanced non-small-cell lung cancer (NSCLC). ...We report 5-year follow-up results from an early phase I study of nivolumab in this patient population and describe characteristics of 5-year survivors. Patients and Methods Patients with pretreated, advanced NSCLC received nivolumab 1, 3, or 10 mg/kg every 2 weeks in 8-week cycles for up to 96 weeks. OS from the time of first dose was estimated by the Kaplan-Meier method. Results The estimated 5-year OS rate was 16% for all treated patients (N = 129); 5-year OS rates were similar for squamous (16%) and nonsquamous (15%) NSCLC. Of 16 5-year survivors, most (88%) were known current or former smokers. Of 10 5-year survivors with quantifiable PD-1 ligand 1 expression, 70% had ≥ 1% PD-1 ligand 1 expression at baseline. Twelve 5-year survivors (75%) achieved a partial response to nivolumab per Response Evaluation Criteria in Solid Tumors, version 1.0, and two each (12%) had stable disease and progressive disease as best response. Nine 5-year survivors (56%) completed the maximum 96 weeks of nivolumab; four (25%) discontinued owing to adverse events and three (19%) owing to disease progression. As of a November 2016 database lock, 12 5-year survivors (75%) received no subsequent therapy and were without evidence of progressive disease at last follow-up. Conclusions Nivolumab treatment resulted in long-term OS and durable responses in a proportion of patients with pretreated advanced NSCLC. Long-term survivors had diverse baseline and on-treatment characteristics.
Approximately 10% of
-activating mutations occur as in-frame insertion mutations in exon 20 of the
kinase domain (
ins20).
ins20 mutations have not demonstrated the same sensitivity to early ...generations of EGFR tyrosine kinase inhibitors (TKI) as canonical activating
mutations such as del19 and L858R. Development of effective therapies for this subset of patients has been challenging, but recent years have seen more rapid progress in these efforts. In this review, we describe the molecular and clinicopathologic features of
ins20 mutations and summarize recent data on emerging therapies for patients with this subtype of
-mutant non-small cell lung cancer (NSCLC). SIGNIFICANCE: When activating mutations in
were first discovered in lung cancer, the lack of sensitivity of tumors harboring
ins20 mutations to early-generation EGFR TKIs resulted in this subset of
-mutant tumors being initially classified as an untargetable or intrinsically resistant subpopulation. In addition, the diversity of mutations within
exon 20 and resultant challenges identifying them on routine clinical genotyping tests led to underestimation of their frequency. However, recent scientific progress in targeting
ins20 mutations as well as more effective identification of this clinical cohort has enhanced our ability to develop effective therapies for patients with this subtype of
-mutant NSCLC.
Evolved resistance to tyrosine kinase inhibitor (TKI)-targeted therapies remains a major clinical challenge. In epidermal growth factor receptor (EGFR) mutant non-small-cell lung cancer (NSCLC), ...failure of EGFR TKIs can result from both genetic and epigenetic mechanisms of acquired drug resistance. Widespread reports of histologic and gene expression changes consistent with an epithelial-to-mesenchymal transition (EMT) have been associated with initially surviving drug-tolerant persister cells, which can seed bona fide genetic mechanisms of resistance to EGFR TKIs. While therapeutic approaches targeting fully resistant cells, such as those harboring an EGFR
mutation, have been developed, a clinical strategy for preventing the emergence of persister cells remains elusive. Using mesenchymal cell lines derived from biopsies of patients who progressed on EGFR TKI as surrogates for persister populations, we performed whole-genome CRISPR screening and identified fibroblast growth factor receptor 1 (FGFR1) as the top target promoting survival of mesenchymal EGFR mutant cancers. Although numerous previous reports of FGFR signaling contributing to EGFR TKI resistance in vitro exist, the data have not yet been sufficiently compelling to instigate a clinical trial testing this hypothesis, nor has the role of FGFR in promoting the survival of persister cells been elucidated. In this study, we find that combining EGFR and FGFR inhibitors inhibited the survival and expansion of EGFR mutant drug-tolerant cells over long time periods, preventing the development of fully resistant cancers in multiple vitro models and in vivo. These results suggest that dual EGFR and FGFR blockade may be a promising clinical strategy for both preventing and overcoming EMT-associated acquired drug resistance and provide motivation for the clinical study of combined EGFR and FGFR inhibition in EGFR-mutated NSCLCs.
Cancer-associated fibroblasts (CAFs) are highly heterogeneous. With the lack of a comprehensive understanding of CAFs' functional distinctions, it remains unclear how cancer treatments could be ...personalized based on CAFs in a patient's tumor. We have established a living biobank of CAFs derived from biopsies of patients' non-small lung cancer (NSCLC) that encompasses a broad molecular spectrum of CAFs in clinical NSCLC. By functionally interrogating CAF heterogeneity using the same therapeutics received by patients, we identify three functional subtypes: (1) robustly protective of cancers and highly expressing HGF and FGF7; (2) moderately protective of cancers and highly expressing FGF7; and (3) those providing minimal protection. These functional differences among CAFs are governed by their intrinsic TGF-β signaling, which suppresses HGF and FGF7 expression. This CAF functional classification correlates with patients' clinical response to targeted therapies and also associates with the tumor immune microenvironment, therefore providing an avenue to guide personalized treatment.
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•A living biobank of CAFs from NSCLC patients recapitulates clinical CAF heterogeneity•Therapeutic profiling of the NSCLC CAFs reveals three distinctive functional subtypes•Subtype I and II CAFs have high HGF and FGF7 expression and protect cancer cells•Subtype III CAFs associate with better clinical response and immune cell migration
Hu et al. identify that cancer-associated fibroblasts (CAFs) derived from non-small cell lung cancer patients are functionally heterogeneous. These functional distinctions directly impact response to clinical anticancer treatment and associate with the tumor immune microenvironment. Thus, CAF functional heterogeneity defines a unique parameter for designing more personalized treatments.
Preclinical data suggest that EGFR tyrosine kinase inhibitors (TKIs) plus MET TKIs are a possible treatment for EGFR mutation-positive lung cancers with MET-driven acquired resistance. Phase 1 safety ...data of savolitinib (also known as AZD6094, HMPL-504, volitinib), a potent, selective MET TKI, plus osimertinib, a third-generation EGFR TKI, have provided recommended doses for study. Here, we report the assessment of osimertinib plus savolitinib in two global expansion cohorts of the TATTON study.
In this multi-arm, multicentre, open-label, phase 1b study, we enrolled adult patients (aged ≥18 years) with locally advanced or metastatic, MET-amplified, EGFR mutation-positive non-small-cell lung cancer, who had progressed on EGFR TKIs. We considered two expansion cohorts: parts B and D. Part B consisted of three cohorts of patients: those who had been previously treated with a third-generation EGFR TKI (B1) and those who had not been previously treated with a third-generation EGFR TKI who were either Thr790Met negative (B2) or Thr790Met positive (B3). In part B, patients received oral osimertinib 80 mg and savolitinib 600 mg daily; after a protocol amendment (March 12, 2018), patients who weighed no more than 55 kg received a 300 mg dose of savolitinib. Part D enrolled patients who had not previously received a third-generation EGFR TKI and were Thr790Met negative; these patients received osimertinib 80 mg plus savolitinib 300 mg. Primary endpoints were safety and tolerability, which were assessed in all dosed patients. Secondary endpoints included the proportion of patients who had an objective response per RECIST 1.1 and was assessed in all dosed patients and all patients with centrally confirmed MET amplification. Here, we present an interim analysis with data cutoff on March 29, 2019. This study is registered with ClinicalTrials.gov, NCT02143466.
Between May 26, 2015, and Feb 14, 2019, we enrolled 144 patients into part B and 42 patients into part D. In part B, 138 patients received osimertinib plus savolitinib 600 mg (n=130) or 300 mg (n=8). In part D, 42 patients received osimertinib plus savolitinib 300 mg. 79 (57%) of 138 patients in part B and 16 (38%) of 42 patients in part D had adverse events of grade 3 or worse. 115 (83%) patients in part B and 25 (60%) patients in part D had adverse events possibly related to savolitinib and serious adverse events were reported in 62 (45%) patients in part B and 11 (26%) patients in part D; two adverse events leading to death (acute renal failure and death, cause unknown) were possibly related to treatment in part B. Objective partial responses were observed in 66 (48%; 95% CI 39–56) patients in part B and 23 (64%; 46–79) in part D.
The combination of osimertinib and savolitinib has acceptable risk–benefit profile and encouraging antitumour activity in patients with MET-amplified, EGFR mutation-positive, advanced NSCLC, who had disease progression on a previous EGFR TKI. This combination might be a potential treatment option for patients with MET-driven resistance to EGFR TKIs.
AstraZeneca.
The LUX-Lung 3 study investigated the efficacy of chemotherapy compared with afatinib, a selective, orally bioavailable ErbB family blocker that irreversibly blocks signaling from epidermal growth ...factor receptor (EGFR/ErbB1), human epidermal growth factor receptor 2 (HER2/ErbB2), and ErbB4 and has wide-spectrum preclinical activity against EGFR mutations. A phase II study of afatinib in EGFR mutation-positive lung adenocarcinoma demonstrated high response rates and progression-free survival (PFS).
In this phase III study, eligible patients with stage IIIB/IV lung adenocarcinoma were screened for EGFR mutations. Mutation-positive patients were stratified by mutation type (exon 19 deletion, L858R, or other) and race (Asian or non-Asian) before two-to-one random assignment to 40 mg afatinib per day or up to six cycles of cisplatin plus pemetrexed chemotherapy at standard doses every 21 days. The primary end point was PFS by independent review. Secondary end points included tumor response, overall survival, adverse events, and patient-reported outcomes (PROs).
A total of 1,269 patients were screened, and 345 were randomly assigned to treatment. Median PFS was 11.1 months for afatinib and 6.9 months for chemotherapy (hazard ratio HR, 0.58; 95% CI, 0.43 to 0.78; P = .001). Median PFS among those with exon 19 deletions and L858R EGFR mutations (n = 308) was 13.6 months for afatinib and 6.9 months for chemotherapy (HR, 0.47; 95% CI, 0.34 to 0.65; P = .001). The most common treatment-related adverse events were diarrhea, rash/acne, and stomatitis for afatinib and nausea, fatigue, and decreased appetite for chemotherapy. PROs favored afatinib, with better control of cough, dyspnea, and pain.
Afatinib is associated with prolongation of PFS when compared with standard doublet chemotherapy in patients with advanced lung adenocarcinoma and EGFR mutations.
Summary Background Most patients with non-small-cell lung cancer tumours that have EGFR mutations have deletion mutations in exon 19 or the Leu858Arg point mutation in exon 21, or both (ie, common ...mutations). However, a subset of patients (10%) with mutations in EGFR have tumours that harbour uncommon mutations. There is a paucity of data regarding the sensitivity of these tumours to EGFR inhibitors. Here we present data for the activity of afatinib in patients with advanced non-small-cell lung cancer that have tumours harbouring uncommon EGFR mutations. Methods In this post-hoc analysis, we used prospectively collected data from tyrosine kinase inhibitor-naive patients with EGFR mutation-positive advanced (stage IIIb–IV) lung adenocarcinomas who were given afatinib in a single group phase 2 trial (LUX-Lung 2), and randomised phase 3 trials (LUX-Lung 3 and LUX-Lung 6). Analyses were done in the intention-to-treat population, including all randomly assigned patients with uncommon EGFR mutations. The type of EGFR mutation (exon 19 deletion del19, Leu858Arg point mutation in exon 21, or other) and ethnic origin (LUX-Lung 3 only; Asian vs non-Asian) were pre-specified stratification factors in the randomised trials. We categorised all uncommon mutations as: point mutations or duplications in exons 18–21 (group 1); de-novo Thr790Met mutations in exon 20 alone or in combination with other mutations (group 2); or exon 20 insertions (group 3). We also assessed outcomes in patients with the most frequent uncommon mutations, Gly719Xaa, Leu861Gln, and Ser768Ile, alone or in combination with other mutations. Response was established by independent radiological review. These trials are registered with ClinicalTrials.gov , numbers NCT00525148 , NCT00949650 , and NCT01121393. Findings Of 600 patients given afatinib across the three trials, 75 (12%) patients had uncommon EGFR mutations (38 in group 1, 14 in group 2, 23 in group 3). 27 (71·1%, 95% CI 54·1–84·6) patients in group 1 had objective responses, as did two (14·3%, 1·8–42·8) in group 2 and two (8·7%, 1·1–28·0) in group 3. Median progression-free survival was 10·7 months (95% CI 5·6–14·7) in group 1, 2·9 months (1·2–8·3) in group 2; and 2·7 months (1·8–4·2) in group 3. Median overall survival was 19·4 months (95% CI 16·4–26·9) in group 1, 14·9 months (8·1–24·9) in group 2, and 9·2 months (4·1–14·2) in group 3. For the most frequent uncommon mutations, 14 (77·8%, 95% CI 52·4–93·6) patients with Gly719Xaa had an objective response, as did nine (56·3%, 29·9–80·2) with Leu861Gln, and eight (100·0%, 63·1–100·0) with Ser768Ile. Interpretation Afatinib was active in non-small-cell lung cancer tumours that harboured certain types of uncommon EGFR mutations, especially Gly719Xaa, Leu861Gln, and Ser768Ile, but less active in other mutations types. Clinical benefit was lower in patients with de-novo Thr790Met and exon 20 insertion mutations. These data could help inform clinical decisions for patients with non-small-cell lung cancer harbouring uncommon EGFR mutations. Funding Boehringer Ingelheim.
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