exon 14 splice site alterations that cause exon skipping at the mRNA level (
ex14) are actionable oncogenic drivers amenable to therapy with MET tyrosine kinase inhibitors (TKI); however, secondary ...resistance eventually arises in most cases while other tumors display primary resistance. Beyond relatively uncommon on-target MET kinase domain mutations, mechanisms underlying primary and acquired resistance remain unclear.
We examined clinical and genomic data from 113 patients with lung cancer with
ex14. MET TKI resistance due to
mutation was functionally evaluated using
and
models.
Five of 113 patients (4.4%) with
ex14 had concurrent
G12 mutations, a rate of
cooccurrence significantly higher than in other major driver-defined lung cancer subsets. In one patient, the
mutation was acquired post-crizotinib, while the remaining 4
ex14 patients harbored the
mutation prior to MET TKI therapy. Gene set enrichment analysis of transcriptomic data from lung cancers with
ex14 revealed preferential activation of the KRAS pathway. Moreover, expression of oncogenic KRAS enhanced MET expression. Using isogenic and patient-derived models, we show that
mutation results in constitutive activation of RAS/ERK signaling and resistance to MET inhibition. Dual inhibition of MET or EGFR/ERBB2 and MEK reduced growth of cell line and xenograft models.
mutation is a recurrent mechanism of primary and secondary resistance to MET TKIs in
ex14 lung cancers. Dual inhibition of MET or EGFR/ERBB2 and MEK may represent a potential therapeutic approach in this molecular cohort.
Background Primary analysis from the pivotal ERIVANCE BCC study resulted in approval of vismodegib, a Hedgehog pathway inhibitor indicated for treatment of adults with metastatic or locally advanced ...basal cell carcinoma (BCC) that has recurred after surgery or for patients who are not candidates for surgery or radiation. Objective An efficacy and safety analysis was conducted 12 months after primary analysis. Methods This was a multinational, multicenter, nonrandomized, 2-cohort study in patients with measurable and histologically confirmed locally advanced or metastatic BCC taking oral vismodegib (150 mg/d). Primary outcome measure was objective response rate (complete and partial responses) assessed by independent review facility. Results After 12 months of additional follow-up, median duration of exposure to vismodegib was 12.9 months. Objective response rate increased from 30.3% to 33.3% in patients with metastatic disease, and from 42.9% to 47.6% in patients with the locally advanced form. Median duration of response in patients with locally advanced BCC increased from 7.6 to 9.5 months. No new safety signals emerged with extended treatment duration. Limitations Limitations include low prevalence of advanced BCC and challenges of designing a study with heterogenous manifestations. Conclusion The 12-month update of the study confirms the efficacy and safety of vismodegib in management of advanced BCC.
Tumor spread through air spaces (STAS) has prognostic significance in lung adenocarcinoma and squamous cell carcinoma. We sought to investigate the prognostic importance of STAS in lung ...neuroendocrine tumors (NETs).
All tumor slides from patients with resected pathologic stage I to III lung NETs (N = 487) (299 with typical carcinoid TC, 38 with atypical carcinoid AC, 93 with large cell neuroendocrine carcinoma LCNEC, and 57 with SCLC) treated between 1992 and 2012 were evaluated for presence of STAS. Cumulative incidence of recurrence (CIR) and lung cancer–specific cumulative incidence of death (LC-CID) were analyzed by using a competing-risks approach.
STAS was identified in 26% of NETs (16% of TCs, 37% of ACs, 43% of LCNECs, and 46% of SCLCs). STAS was associated with distant metastasis, as well as with higher CIR and LC-CID in the overall cohort and in the AC, LCNEC, and SCLC cohorts (owing to a small number of recurrences and deaths <5, prognostic analysis was not performed in the TC cohort). In multivariable analysis stratified by stage, STAS was significantly associated with higher CIR (subhazard ratio = 2.85, 95% confidence interval: 1.73–4.68, p < 0.001) and LC-CID (subhazard ratio = 2.72, 95% confidence interval: 1.57–4.70, p < 0.001), independent of histologic subtype. STAS was independently associated with CIR and LC-CID in the LCNEC cohort and LC-CID in the SCLC cohort.
In patients with lung NETs, STAS is associated with early distant metastasis and worse LC-CID. In patients with LCNEC or SCLC, STAS is an independent poor prognostic factor.
Over the past several years, we have witnessed a resurgence of interest in the biology and therapeutic vulnerabilities of small-cell lung cancer (SCLC). This has been driven in part through the ...development of a more extensive array of representative models of disease, including a diverse variety of genetically engineered mouse models and human tumor xenografts. Herein, we review recent progress in SCLC model development, and consider some of the particularly active avenues of translational research in SCLC, including interrogation of intratumoral heterogeneity, insights into the cell of origin and oncogenic drivers, mechanisms of chemoresistance, and new therapeutic opportunities including biomarker-directed targeted therapies and immunotherapies. Whereas SCLC remains a highly lethal disease, these new avenues of translational research, bringing together mechanism-based preclinical and clinical research, offer new hope for patients with SCLC.
Profiling of circulating tumor DNA (ctDNA) in the bloodstream shows promise for noninvasive cancer detection. Chromatin fragmentation features have previously been explored to infer gene expression ...profiles from cell-free DNA (cfDNA), but current fragmentomic methods require high concentrations of tumor-derived DNA and provide limited resolution. Here we describe promoter fragmentation entropy as an epigenomic cfDNA feature that predicts RNA expression levels at individual genes. We developed 'epigenetic expression inference from cell-free DNA-sequencing' (EPIC-seq), a method that uses targeted sequencing of promoters of genes of interest. Profiling 329 blood samples from 201 patients with cancer and 87 healthy adults, we demonstrate classification of subtypes of lung carcinoma and diffuse large B cell lymphoma. Applying EPIC-seq to serial blood samples from patients treated with PD-(L)1 immune-checkpoint inhibitors, we show that gene expression profiles inferred by EPIC-seq are correlated with clinical response. Our results indicate that EPIC-seq could enable noninvasive, high-throughput tissue-of-origin characterization with diagnostic, prognostic and therapeutic potential.
rearrangements are oncogenic drivers that are enriched in invasive mucinous adenocarcinomas (IMA) of the lung. The oncoprotein binds ERBB3-ERBB2 heterodimers and activates downstream signaling, ...supporting a therapeutic paradigm of ERBB3/ERBB2 inhibition. As proof of concept, a durable response was achieved with anti-ERBB3 mAb therapy (GSK2849330) in an exceptional responder with an
-rearranged IMA on a phase I trial (NCT01966445). In contrast, response was not achieved with anti-ERBB2 therapy (afatinib) in four patients with
-rearranged IMA (including the index patient post-GSK2849330). Although
data supported the use of either ERBB3 or ERBB2 inhibition, these clinical results were consistent with more profound antitumor activity and downstream signaling inhibition with anti-ERBB3 versus anti-ERBB2 therapy in an
-rearranged patient-derived xenograft model. Analysis of 8,984 and 17,485 tumors in The Cancer Genome Atlas and MSK-IMPACT datasets, respectively, identified
rearrangements with novel fusion partners in multiple histologies, including breast, head and neck, renal, lung, ovarian, pancreatic, prostate, and uterine cancers.
This series highlights the utility of ERBB3 inhibition as a novel treatment paradigm for
-rearranged cancers. In addition, it provides preliminary evidence that ERBB3 inhibition may be more optimal than ERBB2 inhibition. The identification of
rearrangements across various solid tumors supports a basket trial approach to drug development.
.
Disseminated tumors are poorly accessible to nanoscale drug delivery systems because of the vascular barrier, which attenuates extravasation at the tumor site. We investigated P-selectin, a molecule ...expressed on activated vasculature that facilitates metastasis by arresting tumor cells at the endothelium, for its potential to target metastases by arresting nanomedicines at the tumor endothelium. We found that P-selectin is expressed on cancer cells in many human tumors. To develop a targeted drug delivery platform, we used a fucosylated polysaccharide with nanomolar affinity to P-selectin. The nanoparticles targeted the tumor microenvironment to localize chemotherapeutics and a targeted MEK (mitogen-activated protein kinase kinase) inhibitor at tumor sites in both primary and metastatic models, resulting in superior antitumor efficacy. In tumors devoid of P-selectin, we found that ionizing radiation guided the nanoparticles to the disease site by inducing P-selectin expression. Radiation concomitantly produced an abscopal-like phenomenon wherein P-selectin appeared in unirradiated tumor vasculature, suggesting a potential strategy to target disparate drug classes to almost any tumor.
The antiangiogenic agent bevacizumab has been approved for the treatment of non-small cell lung cancer (NSCLC), although the survival benefit associated with this agent is marginal, and toxicities ...and cost are substantial. A recent screen for selective inhibitors of endothelial cell proliferation identified the oral antifungal drug itraconazole as a novel agent with potential antiangiogenic activity. In this article, we define and characterize the antiangiogenic and anticancer activities of itraconazole in relevant preclinical models of angiogenesis and lung cancer. Itraconazole consistently showed potent, specific, and dose-dependent inhibition of endothelial cell proliferation, migration, and tube formation in response to both VEGF- and basic fibroblast growth factor-mediated angiogenic stimulation. In vivo, using primary xenograft models of human NSCLC, oral itraconazole showed single-agent growth-inhibitory activity associated with induction of tumor hypoxia-inducible factor 1 alpha expression and marked inhibition of tumor vascularity. Itraconazole significantly enhanced the antitumor efficacy of the chemotherapeutic agent cisplatin in the same model systems. Taken together, these data suggest that itraconazole has potent and selective inhibitory activity against multiple key aspects of tumor-associated angiogenesis in vitro and in vivo, and strongly support clinical translation of its use. Based on these observations, we have initiated a randomized phase II study comparing the efficacy of standard cytotoxic therapy with or without daily oral itraconazole in patients with recurrent metastatic NSCLC.
Developmental processes underlying normal tissue regeneration have been implicated in cancer, but the degree of their enactment during tumor progression and under the selective pressures of immune ...surveillance, remain unknown. Here we show that human primary lung adenocarcinomas are characterized by the emergence of regenerative cell types, typically seen in response to lung injury, and by striking infidelity among transcription factors specifying most alveolar and bronchial epithelial lineages. In contrast, metastases are enriched for key endoderm and lung-specifying transcription factors, SOX2 and SOX9, and recapitulate more primitive transcriptional programs spanning stem-like to regenerative pulmonary epithelial progenitor states. This developmental continuum mirrors the progressive stages of spontaneous outbreak from metastatic dormancy in a mouse model and exhibits SOX9-dependent resistance to natural killer cells. Loss of developmental stage-specific constraint in macrometastases triggered by natural killer cell depletion suggests a dynamic interplay between developmental plasticity and immune-mediated pruning during metastasis.
Purpose Human epidermal growth factor receptor 2 ( HER2, ERBB2)-activating mutations occur in 2% of lung cancers. We assessed the activity of ado-trastuzumab emtansine, a HER2-targeted antibody-drug ...conjugate, in a cohort of patients with HER2-mutant lung cancers as part of a phase II basket trial. Patients and Methods Patients received ado-trastuzumab emtansine at 3.6 mg/kg intravenously every 3 weeks until progression. The primary end point was overall response rate using Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. A Simon two-stage optimal design was used. Other end points included progression-free survival and toxicity. HER2 testing was performed on tumor tissue by next generation sequencing, fluorescence in situ hybridization, immunohistochemistry, and protein mass spectrometry. Results We treated 18 patients with advanced HER2-mutant lung adenocarcinomas. The median number of prior systemic therapies was two (range, zero to four prior therapies). The partial response rate was 44% (95% CI, 22% to 69%), meeting the primary end point. Responses were seen in patients with HER2 exon 20 insertions and point mutations in the kinase, transmembrane, and extracellular domains. Concurrent HER2 amplification was observed in two patients. HER2 immunohistochemistry ranged from 0 to 2+ and did not predict response, and responders had low HER2 protein expression measured by mass spectrometry. The median progression-free survival was 5 months (95% CI, 3 to 9 months). Toxicities included grade 1 or 2 infusion reactions, thrombocytopenia, and elevated hepatic transaminases. No patient stopped therapy as a result of toxicity or died on study. Conclusion Ado-trastuzumab emtansine is an active agent in patients with HER2-mutant lung cancers. This is the first positive trial in this molecular subset of lung cancers. Further use and study of this agent are warranted.
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