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1.
Artigo em Inglês | MEDLINE | ID: mdl-31944535

RESUMO

The incidence of melanoma is rising globally including China. Comparing to Caucasians, the incidence of non-cutaneous melanomas is significantly higher in Chinese. Herein, we performed genomic profiling of 89 Chinese surgically resected primary melanomas, including acral (n = 54), cutaneous (n = 22), and mucosal (n = 13), by hybrid capture-based next-generation sequencing. We show that mucosal melanomas tended to harbor more pathogenic mutations than other types of melanoma, though the biological significance of this finding remains uncertain. Chromosomal arm-level alterations including 6q, 9p, and 10p/q loss were highly recurrent in all subtypes, but mucosal melanoma was significantly associated with increased genomic instability. Importantly, 7p gain significantly correlated with unfavorable clinical outcomes in non-cutaneous melanomas, representing an intriguing prognostic biomarker of those subtypes. Furthermore, focal amplification of 4q12 (KIT, KDR, and PDGFRα) and RAD51 deletion were more abundant in mucosal melanoma, while NOTCH2 amplification was enriched in acral melanoma. Additionally, cutaneous melanomas had higher mutation load than acral melanomas, while mucosal melanomas did not differ from other subtypes in mutation burden. Together, our data revealed important features of acral and mucosal melanomas in Chinese including distinctive driver mutation pattern and increased genomic instability. These findings highlight the possibilities of combination therapies in the clinical management of melanoma.

2.
Nat Commun ; 10(1): 5463, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31784520

RESUMO

Iron Regulatory Protein 1 (IRP1) is a bifunctional cytosolic iron sensor. When iron levels are normal, IRP1 harbours an iron-sulphur cluster (holo-IRP1), an enzyme with aconitase activity. When iron levels fall, IRP1 loses the cluster (apo-IRP1) and binds to iron-responsive elements (IREs) in messenger RNAs (mRNAs) encoding proteins involved in cellular iron uptake, distribution, and storage. Here we show that mutations in the Drosophila 1,4-Alpha-Glucan Branching Enzyme (AGBE) gene cause porphyria. AGBE was hitherto only linked to glycogen metabolism and a fatal human disorder known as glycogen storage disease type IV. AGBE binds specifically to holo-IRP1 and to mitoNEET, a protein capable of repairing IRP1 iron-sulphur clusters. This interaction ensures nuclear translocation of holo-IRP1 and downregulation of iron-dependent processes, demonstrating that holo-IRP1 functions not just as an aconitase, but throttles target gene expression in anticipation of declining iron requirements.

4.
Clin Lung Cancer ; 2019 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-31761448

RESUMO

BACKGROUND: Neurotrophin receptor kinase (NTRK) gene fusions (NTRK+) are rare but actionable oncogenic drivers present in a wide variety of solid tumors. However, the clinicopathologic characteristics of NTRK1 fusion-positive non-small-cell lung cancer are largely unknown. MATERIALS AND METHODS: Lung cancer tissue specimens and/or circulating cell-free DNA from patients with lung cancer who had undergone molecular profiling at a Clinical Laboratory Improvement Amendments (CLIA)-certified genomics laboratory in China were retrospectively reviewed. The laboratory performed NTRK1 fusion detection using hybridization-based targeted next-generation sequencing. The patients' clinical characteristics and treatment history were retrieved from the database for further evaluation. RESULTS: A total of 21,155 Chinese lung cancer cases had undergone molecular profiling from April 2016 to March 2019, including 13,630 adenocarcinoma cases. Of these cases, 12 were positive for NTRK1 fusion, including 10 cases of adenocarcinoma (0.073%), 1 primary sarcomatoid carcinoma, and 1 with an unknown histologic classification. Seven fusion partners (CD74, interferon regulatory factor 2 binding protein 2 [IRF2BP2], lamin A/C [LMNA], PHD finger protein 20 [PHF20], sequestosome 1 [SQSTM1], tropomyosin 3 [TPM3], TPR) were identified. Additionally, 1 unique rearrangement occurred upstream of the transcription start site of BCL9 fused to exon 12 of NTRK1 (intragenic region, BCL9-NTRK1). Of the 12 cases of NTRK1+ lung cancer, 6 had had concurrent activating EGFR mutations and/or had received previous treatment with EGFR tyrosine kinase inhibitors (TKIs), with 2 having concurrent EGFR T790M and 1 additional EGFR C797S. CONCLUSIONS: NTRK1+ lung cancer cases are extremely rare with multiple fusion partners. Additionally, emergence of NTRK1+ fusion might act as a resistance mechanism to EGFR TKIs. When performing comprehensive analysis of acquired resistance to EGFR TKIs, the ability to detect NTRK1 fusions will be important.

5.
Cancer ; 125(20): 3535-3544, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31287555

RESUMO

BACKGROUND: Patients with brain metastases (BMs) have a poor prognosis and limited therapeutic options. Lung cancer is the most common primary malignancy giving rise to BMs; thus, understanding the molecular mechanisms behind increased BM risk is essential for identifying therapeutic targets and developing effective interventions. METHODS: Sixty-one patients who underwent surgical resection of primary non-small cell lung cancer (NSCLC) and BMs were retrospectively studied. Comprehensive genomic profiling of primary NSCLC and matched BMs was performed with next-generation sequencing targeting 416 cancer-relevant genes. RESULTS: Mutations of major drivers, including EGFR, KRAS, TP53, and ALK, were highly concordant between primary NSCLC and matched BMs (>80%), whereas discordance suggested the unique genomic evolution and oncogenic mechanisms of NSCLC BMs. BMs also demonstrated higher levels of copy number variations in comparison with primary NSCLC. Furthermore, the alterations of genes encoding CDK4/CCND1, CDKN2A/2B, and PI3K signaling pathways were enriched in BMs, and this suggested their correlation with increased metastatic risk. Indeed, patients with activated PI3K signaling in their primary NSCLC had significantly shorter BM-free survival (hazard ratio, 8.49; P = .0005). In addition, mutated TP53 or an activated WNT pathway via CTNNB1, APC, and AXIN2 mutations trended toward shorter BM-free intervals but not significantly so. CONCLUSIONS: These findings yield detailed insights into the genomic complexity and heterogeneity of primary NSCLC and matched BMs. This study highlights the significant correlation of PI3K signaling with increased metastatic risk in patients with NSCLC and identifies genomic alterations enriched in NSCLC BMs that could serve as prognostic markers and potential therapeutic targets for treating patients with NSCLC BMs.

6.
BMC Cancer ; 19(1): 592, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31208361

RESUMO

BACKGROUND: Pulmonary sarcomatoid carcinoma (SC) consists of both carcinomatous and sarcomatous tumors with high degree of malignancy, rapid progression, and poor prognosis. However, little is known regarding how pulmonary SC develops and progresses. CASE PRESENTATION: A 66-year-old male was initially diagnosed with stage IIIa lung cancer containing both adenocarcinoma (ADC) and SC. Adjuvant chemotherapy was administrated post-surgery, however, recurrence with SC only soon followed. Mutation profiling of the patient's microdissected ADC and SC components of the primary lesion and recurrent tumor was performed by targeted next-generation sequencing (NGS) of 416 cancer-relevant genes. Our data showed that primary SC/ADC and the recurrent SC shared multiple gene mutations including EGFR, NF1, TP53, CDKN2B, and SMARCA4, while both primary and recurrent SCs had a unique TP53 exon 4 splicing mutation frequently observed in sarcoma. Interestingly, a novel PHF20-NTRK1 fusion was acquired in the recurrent SC, which may be a potential driver for SC recurrence. CONCLUSIONS: The molecular genetic characteristics of tumor tissues at different stages reveals a linear tumor evolution model in this case, and support that the primary SC derived from the original lung ADC during the evolution of the tumor. We also identified a novel PHF20-NTRK1 fusion, which may contribute to the disease recurrence, and that can be potentially targeted with NTRK1 inhibitors for treatment.


Assuntos
Adenocarcinoma de Pulmão/complicações , Antígenos de Neoplasias/genética , Biomarcadores Tumorais/genética , Carcinossarcoma/etiologia , Fusão Gênica , Neoplasias Pulmonares/complicações , Doenças Raras/etiologia , Receptor trkA/genética , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/radioterapia , Adenocarcinoma de Pulmão/cirurgia , Idoso , Carcinogênese , Carcinossarcoma/tratamento farmacológico , Carcinossarcoma/radioterapia , Carcinossarcoma/cirurgia , Quimioterapia Adjuvante , Éxons/genética , Evolução Fatal , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Masculino , Recidiva Local de Neoplasia , Doenças Raras/tratamento farmacológico , Doenças Raras/radioterapia , Doenças Raras/cirurgia
7.
Oncologist ; 24(10): 1368-1374, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30872465

RESUMO

BACKGROUND: The efficacy of adjuvant targeted therapy for operable lung cancer is still under debate. Comprehensive genetic profiling is needed for detecting co-mutations in resected epidermal growth factor receptor (EGFR)-mutated lung adenocarcinoma (ADC), which may interfere the efficacy of adjuvant tyrosine kinase inhibitor (TKI) treatment. MATERIALS AND METHODS: Mutation profiling of 416 cancer-relevant genes was conducted for 139 resected stage I-IIIa lung ADCs with EGFR mutations using targeted next-generation sequencing. Co-mutation profiles were systematically analyzed. RESULTS: Rare EGFR alterations other than exon 19 deletion and L858R, such as L861Q (∼3%) and G719A (∼2%), were identified at low frequencies. Approximately 10% of patients had mutations in EGFR exon 20 that could confer resistance to first-generation TKIs. Ninety-one percent of patients harbored at least one co-mutation in addition to the major EGFR mutation. TP53 was the top mutated gene and was found more frequently mutated at later stage. Markedly, NF1 mutations were found only in stage II-III ADCs. Conversely, RB1 mutations were more frequent in stage I ADCs, whereas APC mutations were observed exclusively in this group. Thirty-four percent of patients with EGFR TKI-sensitizing mutations had genetic alterations involving EGFR downstream effectors or bypass pathways that could affect the response to EGFR TKIs, such as PIK3CA, BRCA1, and NOTCH1. CONCLUSION: Operable lung ADCs with EGFR TKI-sensitizing mutations are associated with a high proportion of co-mutations. Mutation profiling of these resected tumors could facilitate in determining the applicability and efficacy of adjuvant EGFR TKI therapeutic strategy. IMPLICATIONS FOR PRACTICE: The efficacy of adjuvant epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) therapy for lung cancer harboring EGFR mutation after surgical resection is still under debate. Next-generation sequencing of 416 cancer-relevant genes in 139 resected lung cancers revealed the co-mutational landscape with background EGFR mutation. Notably, the study identified potential EGFR TKI-resistant mutations in 34.71% of patients with a drug-sensitizing EGFR mutation and who were naive in terms of targeted therapy. A comprehensive mutation profiling of these resected tumors could facilitate in determining the applicability and efficacy of adjuvant EGFR TKI therapeutic strategy for these patients.

8.
J Cancer ; 10(2): 323-331, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30719126

RESUMO

Background: Malignant lymphomas are a group of distinct lymphoid neoplasms, exhibiting marked diversity in biological behaviors and clinical outcomes. Liquid biopsy, such as circulating cell-free DNA (cfDNA), has recently been attempted to be used for mutation profiling of lymphomas using next-generation sequencing (NGS). However, only limited data about cfDNA are restricted in Hodgkin's lymphoma and B cell lymphoma, and there is no report in the T cell lymphoma so far. Patient and Methods: Medical records of a total of 50 lymphoma patients were retrospectively reviewed, and cfDNA samples were analyzed by capture-based NGS targeting 390 lymphoma- and cancer- relevant genes. We sought to explore the clinical utility of cfDNA in establishing the mutation profiles of different lymphoma subtypes and analyze the correlation between cfDNA concentration and other clinical indices such as serum LDH and IPI. Results: Somatic alterations were identified in cfDNA samples with a median of 64 variants per sample. The concentration of cfDNA in the plasma was found to be significantly correlated with the clinical indices in diffuse large B cell lymphoma (DLBCL). The genetic heterogeneity of different lymphoma subtypes was clearly observed in cfDNAs from germinal center B-cell (GCB) DLBCL, non-GCB DLBCL and natural killer/T-cell lymphoma (NKTCL), confirming that distinct molecular mechanisms are involved in the pathogenesis of different lymphomas. Conclusion: Our findings demonstrate that NGS-based cfDNA mutation profiling reveals genetic heterogeneity across lymphoma subtypes, with potential implications for the discovery of therapeutic targets, the exploration of genome evolution and the development of risk-adapted treatment.

9.
Lung Cancer ; 127: 19-24, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30642546

RESUMO

OBJECTIVES: ALK tyrosine kinase inhibitors (TKIs), including crizotinib and several next generation TKIs, have demonstrated beneficial clinical outcomes in ALK-positive non-small cell lung cancer (NSCLC). However, resistance mechanisms following multiple TKI treatments in ALK-positive NSCLC are not fully elucidated. MATERIALS AND METHODS: Mutation profiles of 422 cancer-relevant genes in 52 patients with post-TKI biopsy samples were analyzed using next-generation sequencing (NGS), and compared between patients receiving crizotinib alone (n = 35) and multi-TKIs (n = 17). RESULTS: EML4-ALK variant 3 is the most frequent ALK variants in this cohort, followed by EML4-ALK variant 1. Half of the patients harbored ALK activating mutations upon progression on crizotinib treatment. After multi-TKIs treatment, 59% of the cases developed resistant ALK mutations, and concomitant ALK activating mutations were more commonly observed in this cohort (P = 0.031). Specifically, ALK G1269 A, L1196 M, and C1156Y substitutions were more common in crizotinib-alone samples, while ALK G1202R was significantly more enriched post-multi-TKIs (P = 0.009). Activated bypass signaling tended to be more prevalent in patients post-multi-TKIs. Furthermore, dual activation of ALK and bypass signaling was more frequently found in the multi-TKIs group (5/17, 29%) in contrast to crizotinib-alone (2/35, 6%) (P = 0.031). Additionally, concurrent TP53 mutation demonstrated significantly shorter progression-free survival (PFS) compared with TP53 wildtype in crizotinib-alone group (median PFS: 8 vs 13 months, Hazard Ratio = 1.494, P = 0.019). CONCLUSION: Concurrent ALK activating mutations and/or upregulated bypass signaling are more enriched in patients undergoing multiple ALK TKI treatments compared to crizotinib alone. Concomitant TP53 mutation correlated to unfavorable survival when receiving a single TKI crizotinib.


Assuntos
Anestésicos Combinados/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Crizotinibe/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Adulto , Idoso , Quinase do Linfoma Anaplásico/antagonistas & inibidores , Quinase do Linfoma Anaplásico/genética , Quinase do Linfoma Anaplásico/metabolismo , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Estudos de Coortes , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Mutação/genética , Análise de Sobrevida , Resultado do Tratamento
11.
Int J Cancer ; 144(11): 2677-2682, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30255937

RESUMO

Kinase domain duplications of the epidermal growth factor receptor (EGFR-KDD) have been identified and implicated to be oncogenic in nonsmall cell lung cancers (NSCLCs). However, its prevalence and clinical contributions in lung cancer are largely unknown. Here, we conducted a multicenter record review of 10,759 NSCLC patients who underwent genetic testing using next-generation sequencing (NGS) targeting EGFR exons and the introns involved in EGFR-KDD rearrangements. EGFR-KDDs were identified in a total of 13 patients, which is approximately 0.12% of the total population reviewed, and also consisted of 0.24% (13/5394) of EGFR mutation-positive patients. A total of 85% of patients (11/13) were identified with the canonical EGFR-KDD duplication of exons 18-25, while the remaining two cases harbored duplications of EGFR exons 14-26 and exons 17-25, which have not been previously described. Importantly, none of the 13 patients had other coexisting driver mutations, highlighting the potential oncogenic role of this type of alteration. Three out of five patients who had exon 18-25 duplications showed partial antitumor responses to targeted therapies, while the other two patients demonstrated no clinical improvement. Furthermore, our data suggested that the EGFR T790 M mutation and EGFR amplification may represent the major resistance mechanisms against targeted therapies in tumors bearing EGFR-KDD. In summary, our findings provide valuable insight into the prevalence of EGFR-KDDs in NSCLCs and their clinical outcomes to targeted therapies.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/tratamento farmacológico , Domínios Proteicos/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Análise Mutacional de DNA , Receptores ErbB/genética , Éxons/genética , Feminino , Amplificação de Genes , Humanos , Pulmão/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular/métodos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos
12.
Lung Cancer ; 124: 110-116, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30268447

RESUMO

INTRODUCTION: Increasing evidence leads to a ratiocination that genetic heterogeneity of the lung adenocarcinoma with EGFR mutations may impact clinical responses and outcomes to EGFR tyrosine kinase inhibitor (TKI) treatments. METHODS: We performed genetic profiling of pre-treatment samples of 69 lung adenocarcinoma patients, including tumor FFPE and cell-free DNA (cfDNA), targeting 416 cancer-related genes using next generation sequencing. We analyzed mutation concordance across sample types and investigated potential mechanisms that confer primary resistance to EGFR-TKIs in patients with short progression-free survival (PFS) versus those with long PFS. RESULTS: We detected a total of 200 actionable genetic alterations (mean: 2.9 variants/patient, range: 1-7 variants) in tumor FFPE and 140 actionable genetic alterations (mean: 2.0 variants/patient, range: 0-5 variants) in matched cfDNA, respectively. All patients had EGFR TKI-sensitizing mutations, including EGFR Ex19del, L858R, G719S/C, and L861Q. Concurrent TP53 mutations were most commonly observed in 72.5% of patients, followed by EGFR amplification (20.3%), RB1 (10.1%), PIK3CA (7.2%), and MYC (5.8%). For EGFR activating mutations, the concordance rate was 88.2% between cfDNA and FFPE samples. Furthermore, we identified genes that potentially confer primary resistance to EGFR-TKIs including CDC73, SMAD4, RB1 and PIK3CA. We also report signaling pathways enriched in patients with TKI primary resistance. CONCLUSIONS: We note the genetic complexity and heterogeneity of EGFR-mutated lung adenocarcinoma and underscore that mutation status is highly concordant between tumor FFPE and cfDNA samples. This study also highlights the alterations that potentially confer primary resistance to EGFR TKI treatments in patients who demonstrated short PFS.


Assuntos
Adenocarcinoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Mutação/genética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Supressoras de Tumor/genética , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/farmacologia , Ácidos Nucleicos Livres/genética , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/genética , Perfilação da Expressão Gênica , Humanos , Biópsia Líquida , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Proteínas de Ligação a Retinoblastoma/genética , Estudos Retrospectivos , Transdução de Sinais/genética , Proteína Supressora de Tumor p53/genética , Ubiquitina-Proteína Ligases/genética
13.
Clin Cancer Res ; 24(13): 3097-3107, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29506987

RESUMO

Purpose: The third-generation EGFR tyrosine kinase inhibitor osimertinib is approved to treat patients with EGFR T790M-positive non-small cell lung cancer (NSCLC) who have developed resistance to earlier-generation drugs. Acquired EGFR C797S mutation has been reported to mediate osimertinib resistance in some patients. However, the remaining resistance mechanisms are largely unknown.Experimental Design: We performed mutation profiling using targeted next-generation sequencing (NGS) for 416 cancer-relevant genes on 93 osimertinib-resistant lung cancer patients' samples, mainly cell-free DNAs (cfDNAs), and matched pretreatment samples of 12 patients. In vitro experiments were conducted to functionally study the secondary EGFR mutations identified.Results:EGFR G796/C797, L792, and L718/G719 mutations were identified in 24.7%, 10.8%, and 9.7% of the cases, respectively, with certain mutations coexisting in one patient with different prevalence. L792 and L718 mutants markedly increased the half inhibitory concentration (IC50) of osimertinib in vitro, among which the L718Q mutation conferred the greatest resistance to osimertinib, as well as gefitinib resistance when not coexisting with T790M. Further analysis of the 12 matched pretreatment samples confirmed that these EGFR mutations were acquired during osimertinib treatment. Alterations in parallel or downstream oncogenes such as MET, KRAS, and PIK3CA were also discovered, potentially contributing to the osimertinib-resistance in patients without EGFR secondary mutations.Conclusions: We present comprehensive mutation profiles of a large cohort of osimertinib-resistance lung cancer patients using mainly cfDNA. Besides C797 mutations, novel secondary mutations of EGFR L718 and L792 residues confer osimertinib resistance, both in vitro and in vivo, and are of great clinical and pharmaceutical relevance. Clin Cancer Res; 24(13); 3097-107. ©2018 AACR.


Assuntos
Acrilamidas/farmacologia , Compostos de Anilina/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/genética , Inibidores de Proteínas Quinases/farmacologia , Acrilamidas/química , Adulto , Idoso , Idoso de 80 Anos ou mais , Compostos de Anilina/química , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/química , Receptores ErbB/genética , Receptores ErbB/metabolismo , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Gradação de Tumores , Estadiamento de Neoplasias , Inibidores de Proteínas Quinases/química
14.
Lung Cancer ; 118: 1-5, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29571986

RESUMO

OBJECTIVES: Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are promising targeted therapies for EGFR-mutated non-small-cell lung cancer (NSCLC) patients. However, acquired resistance inevitably develops. Comprehensive and dynamic companion genomic diagnosis can gain insights into underlying resistance mechanisms, thereby help oncologists and patients to make informed decision on the potential benefit of the treatment. MATERIALS AND METHODS: A 67-year-old male who was initially diagnosed of EGFR L858R-mediated NSCLC received multiple lines of chemotherapy and EGFR TKI therapies after surgery. The EGFR mutational status of individual metastatic lesion was determined by genetic testing of the tumor tissue biopsies using next generation sequencing (NGS) throughout the patient's clinical course. An acquired potentially drug-resistant EGFR mutation was functionally validated in vitro and its sensitivity to different EGFR TKIs was assessed simultaneously. RESULTS: We have identified distinct resistance mechanisms to EGFR blockade in different metastatic lung lesions. Acquired EGFR T790M was first detected that leads to the resistance to the gefitinib treatment. Consequently, osimertinib was administrated and the response lasted until disease progressed. We identified a newly acquired EGFR L718V mutation in one lesion in conjunction with L858R, but not T790M, which showed stable disease on the following erlotinib treatment, while EGFR C797S together with L858R/T790M was detected in the other lesion that continuously progressed. In vitro functional studies demonstrated that EGFR-L858R/L718V confers resistance to osimertinib, but retains sensitivity to the second generation TKI afatinib. CONCLUSION: We reported that distinct resistance mechanisms could arise in different metastases within the same patient in response to EGFR blockade. We also demonstrated in vitro that EGFR L718V mutation mediates resistance to osimertinib, but retains sensitivity to afatinib. We evidenced that dynamic companion genomic diagnosis offers valuable information to help define the mechanisms of drug resistance and to guide the selection of subsequent treatment.


Assuntos
Afatinib/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Mutação/genética , Piperazinas/uso terapêutico , Acrilamidas , Idoso , Compostos de Anilina , Carcinogênese , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Cloridrato de Erlotinib/uso terapêutico , Gefitinibe/uso terapêutico , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Inibidores de Proteínas Quinases/uso terapêutico , Células Tumorais Cultivadas
15.
Genetics ; 208(2): 605-622, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29187506

RESUMO

Ecdysteroids are steroid hormones that control many aspects of development and physiology. During larval development, ecdysone is synthesized in an endocrine organ called the prothoracic gland through a series of ecdysteroidogenic enzymes encoded by the Halloween genes. The expression of the Halloween genes is highly restricted and dynamic, indicating that their spatiotemporal regulation is mediated by their tight transcriptional control. In this study, we report that three zinc finger-associated domain (ZAD)-C2H2 zinc finger transcription factors-Séance (Séan), Ouija board (Ouib), and Molting defective (Mld)-cooperatively control ecdysone biosynthesis in the fruit fly Drosophila melanogaster Séan and Ouib act in cooperation with Mld to positively regulate the transcription of neverland and spookier, respectively, two Halloween genes. Remarkably, loss-of-function mutations in séan, ouib, or mld can be rescued by the expression of neverland, spookier, or both, respectively. These results suggest that the three transcription factors have distinct roles in coordinating the expression of just two genes in Drosophila Given that neverland and spookier are located in constitutive heterochromatin, Séan, Ouib, and Mld represent the first example of a transcription factor subset that regulates genes located in constitutive heterochromatin.


Assuntos
Drosophila/genética , Drosophila/metabolismo , Ecdisona/biossíntese , Fatores de Transcrição/metabolismo , Alelos , Animais , Regulação da Expressão Gênica , Larva , Mutação , Fenótipo , Regiões Promotoras Genéticas , Elementos de Resposta , Dedos de Zinco
16.
Dev Cell ; 37(6): 558-70, 2016 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-27326933

RESUMO

Steroid hormones control important developmental processes and are linked to many diseases. To systematically identify genes and pathways required for steroid production, we performed a Drosophila genome-wide in vivo RNAi screen and identified 1,906 genes with potential roles in steroidogenesis and developmental timing. Here, we use our screen as a resource to identify mechanisms regulating intracellular levels of cholesterol, a substrate for steroidogenesis. We identify a conserved fatty acid elongase that underlies a mechanism that adjusts cholesterol trafficking and steroidogenesis with nutrition and developmental programs. In addition, we demonstrate the existence of an autophagosomal cholesterol mobilization mechanism and show that activation of this system rescues Niemann-Pick type C1 deficiency that causes a disorder characterized by cholesterol accumulation. These cholesterol-trafficking mechanisms are regulated by TOR and feedback signaling that couples steroidogenesis with growth and ensures proper maturation timing. These results reveal genes regulating steroidogenesis during development that likely modulate disease mechanisms.


Assuntos
Drosophila melanogaster/genética , Desenvolvimento Embrionário/genética , Testes Genéticos , Genoma de Inseto , Hormônios/biossíntese , Esteroides/biossíntese , Acetiltransferases/metabolismo , Animais , Autofagia/genética , Transporte Biológico/genética , Colesterol/metabolismo , Proteínas de Drosophila/metabolismo , Ecdisona/metabolismo , Metabolismo dos Lipídeos/genética , Fenótipo , Interferência de RNA , Transdução de Sinais/genética , Esfingolipídeos/metabolismo , Fatores de Tempo
17.
Cell Rep ; 16(1): 247-262, 2016 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-27320926

RESUMO

Steroid hormones are ancient signaling molecules found in vertebrates and insects alike. Both taxa show intriguing parallels with respect to how steroids function and how their synthesis is regulated. As such, insects are excellent models for studying universal aspects of steroid physiology. Here, we present a comprehensive genomic and genetic analysis of the principal steroid hormone-producing organs in two popular insect models, Drosophila and Bombyx. We identified 173 genes with previously unknown specific expression in steroid-producing cells, 15 of which had critical roles in development. The insect neuropeptide PTTH and its vertebrate counterpart ACTH both regulate steroid production, but molecular targets of these pathways remain poorly characterized. Identification of PTTH-dependent gene sets identified the nuclear receptor HR4 as a highly conserved target in both Drosophila and Bombyx. We consider this study to be a critical step toward understanding how steroid hormone production and release are regulated in all animal models.


Assuntos
Estruturas Animais/metabolismo , Bombyx/metabolismo , Drosophila melanogaster/metabolismo , Hormônios/biossíntese , Esteroides/biossíntese , Animais , Bombyx/genética , Ritmo Circadiano/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genes de Insetos , Modelos Biológicos , Neuropeptídeos/metabolismo , Especificidade de Órgãos/genética , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fatores de Tempo
18.
Curr Top Dev Biol ; 103: 35-71, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23347515

RESUMO

Insect metamorphosis is one of the most fascinating biological processes in the animal kingdom. The dramatic transition from an immature juvenile to a reproductive adult is under the control of the steroid hormone ecdysone, also known as the insect molting hormone. During Drosophila development, periodic pulses of ecdysone are released from the prothoracic glands, upon which the hormone is rapidly converted in peripheral tissues to its biologically active form, 20-hydroxyecdysone. Each hormone pulse has a unique profile and causes different developmental events, but we only have a rudimentary understanding of how the timing, amplitude, and duration of a given pulse are controlled. A key component involved in the timing of ecdysone pulses is PTTH, a brain-derived neuropeptide. PTTH stimulates ecdysone production through a Ras/Raf/ERK signaling cascade; however, comparatively little is known about the downstream targets of this pathway. In recent years, it has become apparent that transcriptional regulation plays a critical role in regulating the synthesis of ecdysone, but only one transcription factor has a well-defined link to PTTH. Interestingly, many of the ecdysteroidogenic transcription factors were originally characterized as primary response genes in the ecdysone signaling cascade that elicits the biological responses to the hormone in target tissues. To review these developments, we will first provide an overview of the transcription factors that act in the Drosophila ecdysone regulatory hierarchy. We will then discuss the roles of these transcriptional regulators in controlling ecdysone synthesis. In the last section, we will briefly outline transcription factors that likely have roles in regulating ecdysone synthesis but have not been formally identified as downstream effectors of ecdysone.


Assuntos
Drosophila melanogaster/metabolismo , Ecdisona/metabolismo , Fatores de Transcrição/metabolismo , Animais , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Metamorfose Biológica/genética , Transdução de Sinais/genética
19.
PLoS Biol ; 9(9): e1001160, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21980261

RESUMO

In insects, precisely timed periodic pulses of the molting hormone ecdysone control major developmental transitions such as molts and metamorphosis. The synthesis and release of ecdysone, a steroid hormone, is itself controlled by PTTH (prothoracicotopic hormone). PTTH transcript levels oscillate with an 8 h rhythm, but its significance regarding the timing of ecdysone pulses is unclear. PTTH acts on its target tissue, the prothoracic gland (PG), by activating the Ras/Raf/ERK pathway through its receptor Torso, however direct targets of this pathway have yet to be identified. Here, we demonstrate that Drosophila Hormone Receptor 4 (DHR4), a nuclear receptor, is a key target of the PTTH pathway and establishes temporal boundaries by terminating ecdysone pulses. Specifically, we show that DHR4 oscillates between the nucleus and cytoplasm of PG cells, and that the protein is absent from PG nuclei at developmental times when low titer ecdysone pulses occur. This oscillatory behavior is blocked when PTTH or torso function is abolished, resulting in nuclear accumulation of DHR4, while hyperactivating the PTTH pathway results in cytoplasmic retention of the protein. Increasing DHR4 levels in the PG can delay or arrest development. In contrast, reducing DHR4 function in the PG triggers accelerated development, which is caused by precocious ecdysone signaling due to a failure to repress ecdysone pulses. Finally, we show that DHR4 negatively regulates the expression of a hitherto uncharacterized cytochrome P450 gene, Cyp6t3. Disruption of Cyp6t3 function causes low ecdysteroid titers and results in heterochronic phenotypes and molting defects, indicating a novel role in the ecdysone biosynthesis pathway. We propose a model whereby nuclear DHR4 controls the duration of ecdysone pulses by negatively regulating ecdysone biosynthesis through repression of Cyp6t3, and that this repressive function is temporarily overturned via the PTTH pathway by removing DHR4 from the nuclear compartment.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Ecdisona/metabolismo , Larva/crescimento & desenvolvimento , Receptores Citoplasmáticos e Nucleares/metabolismo , Animais , Animais Geneticamente Modificados , Núcleo Celular/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Glândulas Endócrinas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Hormônios de Inseto/metabolismo , Larva/citologia , Larva/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Muda , Mutação , Análise de Sequência com Séries de Oligonucleotídeos , Periodicidade , Fenótipo , Transporte Proteico , Interferência de RNA , Receptores Citoplasmáticos e Nucleares/genética , Transdução de Sinais , Proteínas ras/genética , Proteínas ras/metabolismo
20.
Hepatol Res ; 39(3): 301-12, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19067752

RESUMO

AIM: Liver regeneration is a highly coordinated response to hepatic injury or resection that is controlled by the body's overall requirement for liver function. The level of circulating amino acids in blood increases after acute liver injury and administration of amino acid mixtures induces hepatic DNA replication. These findings suggest a close connection between amino acid metabolism and hepatic proliferation. However, the underlying molecular mechanisms have not been completely elucidated. Here, we applied a cDNA micro-array technique to analyze expression profiles of the genes associated with nitrogen and amino acid metabolism during liver regeneration in mice following treatment with CCl(4). METHODS: Seventy-nine genes were identified for their significantly altered expression patterns at different stages of liver damage and regeneration. RESULTS: We observed that the numbers of down-regulated genes were remarkably higher than that of up-regulated genes at 1.5 days following carbon tetrachloride administration when hepatic DNA replication was most active, indicating the existence of a counter balance between cell proliferation and liver metabolism functions. CONCLUSIONS: Our results suggest that suppression of amino acids metabolism after acute liver injury results in the accumulation of amino acids in plasma that serves as a driving force for liver regeneration.

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