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Purpose: Abrogation of Notch signaling, which is pivotal for lung development and pulmonary epithelial cell fate decisions was shown to be involved in the aggressiveness and the differentiation of lung carcinomas. Additionally, the transcription factors YAP and TAZ which are involved in the Hippo pathway, were recently shown to be tightly linked with Notch signaling and to regulate the cell fate in epidermal stem cells. Thus, we aim to elucidate the effects of conditional Notch1 deficiency on carcinogenesis and TAZ expression in lung cancer. Methods: We investigated the effect of conditional Cre-recombinase mediated Notch1 knock-out on lung cancer cells in vivo using an autochthonous mouse model of lung adenocarcinomas driven by Kras LSL-G12V and comprehensive immunohistochemical analysis. In addition, we analyzed clinical samples and human lung cancer cell lines for TAZ expression and supported our findings by publicly available data from The Cancer Genome Atlas (TCGA). Results: In mice, we found induction of papillary adenocarcinomas and protrusions of tumor cells from the bronchiolar lining upon Notch1 deficiency. Moreover, the mutated Kras driven lung tumors with deleted Notch1 showed increased TAZ expression and focal nuclear translocation which was frequently observed in human pulmonary adenocarcinomas and squamous cell carcinomas of the lung, but not in small cell lung carcinomas. In addition, we used data from TCGA to show that putative inactivating NOTCH1 mutations co-occur with KRAS mutations and genomic amplifications in lung adenocarcinomas. Conclusion: Our in vivo study provides evidence that Notch1 deficiency in mutated Kras driven lung carcinomas contributes to lung carcinogenesis in a subgroup of patients by increasing TAZ expression who might benefit from TAZ signaling blockade.
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Aciltransferases/metabolismo , Brônquios/patologia , Modelos Animais de Doenças , Neoplasias Pulmonares/patologia , Mutação , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptor Notch1/fisiologia , Aciltransferases/genética , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/metabolismo , Adenocarcinoma de Pulmão/patologia , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Brônquios/metabolismo , Carcinogênese , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Prognóstico , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/metabolismo , Carcinoma de Pequenas Células do Pulmão/patologia , Células Tumorais CultivadasRESUMO
OBJECTIVE: Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) is an essential tool in the diagnosis of pancreatic lesions. The aim of this study was to evaluate the diagnostic accuracy of cytology from EUS-FNA, to correlate the results with the corresponding histopathological diagnoses and to analyse the impact of retrospective assignment of the Papanicolaou Society of Cytopathology (PSC) reporting system categories. METHODS: All pancreatic FNA specimens reported at the Royal Free Hospital during a 2-year period were retrospectively collected and assigned to the PSC system categories. Any available corresponding histological samples were assessed for concordance. RESULTS: In total, 236 cytology specimens from 223 patients were identified, of which 108 (45.8%) had corresponding histology samples. The main reason for cyto-histological discrepancy was sampling error. Interpretive error was identified in one case. Overall, sensitivity was 92.5%, specificity was 100%, diagnostic accuracy of cytology was 95%, false-positive rate was 0% and false-negative rate was 7.5%. The implementation of the new reporting system reduced the number of cases in the atypical category. All cases previously categorised as suspicious or malignant remained in the same category. CONCLUSIONS: EUS-FNA is an accurate method for evaluating pancreatobiliary lesions. The implementation of the Papanicolaou Society of Cytopathology diagnostic system enhances standardisation of the reporting terminology and reduces the number of samples in the non-standardised and equivocal atypical category.
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Pâncreas/diagnóstico por imagem , Pâncreas/patologia , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Adulto , Idoso , Técnicas Citológicas/métodos , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sociedades Médicas , Adulto JovemRESUMO
Carcinosarcomas of the gallbladder are extremely rare tumors and infrequently reported in the literature. We demonstrate a case of a 64-year-old female who presented with a 2-month history of a right upper quadrant mass, intermittent fevers, and abdominal distension following recent travel to Ghana. A computed tomography (CT) scan of the abdomen and pelvis demonstrated a large hepatic lesion with co-existing gallbladder distension, suggestive of a hepatic abscess. The patient was initially managed with intravenous antibiotics but failed to respond to treatment. A subsequent magnetic resonance imaging (MRI) scan of the liver showed a locally invasive lobulated soft tissue lesion arising from the gallbladder fundus and extending into the liver parenchyma. The lesion was surgically excised with a central hepatectomy. Histopathologic analysis showed a carcinosarcoma of the gallbladder.
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Anti-angiogenic treatment targeting vascular endothelial growth factor (VEGF)-VEGFR2 signaling has shown limited efficacy in lung cancer patients. Here, we demonstrate that inhibition of VEGFR2 in tumor cells, expressed in â¼20% of non-squamous non-small cell lung cancer (NSCLC) patients, leads to a pro-invasive phenotype. Drug-induced inhibition of tumor VEGFR2 interferes with the formation of the EphA2/VEGFR2 heterocomplex, thereby allowing RSK to interact with Serine 897 of EphA2. Inhibition of RSK decreases phosphorylation of Serine 897 EphA2. Selective genetic modeling of Serine 897 of EphA2 or inhibition of EphA2 abrogates the formation of metastases in vivo upon VEGFR2 inhibition. In summary, these findings demonstrate that VEGFR2-targeted therapy conditions VEGFR2-positive NSCLC to Serine 897 EphA2-dependent aggressive tumor growth and metastasis. These data shed light on the molecular mechanisms explaining the limited efficacy of VEGFR2-targeted anti-angiogenic treatment in lung cancer patients.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Receptor EphA2/metabolismo , Serina/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Invasividade Neoplásica , Metástase Neoplásica , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genéticaRESUMO
MYC paralogs are frequently activated in small cell lung cancer (SCLC) but represent poor drug targets. Thus, a detailed mapping of MYC-paralog-specific vulnerabilities may help to develop effective therapies for SCLC patients. Using a unique cellular CRISPR activation model, we uncover that, in contrast to MYCN and MYCL, MYC represses BCL2 transcription via interaction with MIZ1 and DNMT3a. The resulting lack of BCL2 expression promotes sensitivity to cell cycle control inhibition and dependency on MCL1. Furthermore, MYC activation leads to heightened apoptotic priming, intrinsic genotoxic stress and susceptibility to DNA damage checkpoint inhibitors. Finally, combined AURK and CHK1 inhibition substantially prolongs the survival of mice bearing MYC-driven SCLC beyond that of combination chemotherapy. These analyses uncover MYC-paralog-specific regulation of the apoptotic machinery with implications for genotype-based selection of targeted therapeutics in SCLC patients.
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Apoptose/genética , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Carcinoma de Pequenas Células do Pulmão/genética , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Sistemas CRISPR-Cas/genética , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/genética , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Terapia de Alvo Molecular/métodos , Proteínas Proto-Oncogênicas c-myc/genética , RNA Interferente Pequeno/metabolismo , Carcinoma de Pequenas Células do Pulmão/tratamento farmacológicoRESUMO
PURPOSE: BRCA1-deficient breast cancers carry a specific DNA copy-number signature ("BRCA1-like") and are hypersensitive to DNA double-strand break (DSB) inducing compounds. Here, we explored whether (i) EZH2 is overexpressed in human BRCA1-deficient breast tumors and might predict sensitivity to DSB-inducing drugs; (ii) EZH2 inhibition potentiates cisplatin efficacy in Brca1-deficient murine mammary tumors. EXPERIMENTAL DESIGN: EZH2 expression was analyzed in 497 breast cancers using IHC or RNA sequencing. We classified 370 tumors by copy-number profiles as BRCA1-like or non-BRCA1-like and examined its association with EZH2 expression. Additionally, we assessed BRCA1 loss through mutation or promoter methylation status and investigated the predictive value of EZH2 expression in a study population of breast cancer patients treated with adjuvant high-dose platinum-based chemotherapy compared with standard anthracycline-based chemotherapy. To explore whether EZH2 inhibition by GSK126 enhances sensitivity to platinum drugs in EZH2-overexpressing breast cancers we used a Brca1-deficient mouse model. RESULTS: The highest EZH2 expression was found in BRCA1-associated tumors harboring a BRCA1 mutation, BRCA1-promoter methylation or were classified as BRCA1 like. We observed a greater benefit from high-dose platinum-based chemotherapy in BRCA1-like and non-BRCA1-like patients with high EZH2 expression. Combined treatment with the EZH2 inhibitor GSK126 and cisplatin decreased cell proliferation and improved survival in Brca1-deficient mice in comparison with single agents. CONCLUSIONS: Our findings demonstrate that EZH2 is expressed at significantly higher levels in BRCA1-deficient breast cancers. EZH2 overexpression can identify patients with breast cancer who benefit significantly from intensified DSB-inducing platinum-based chemotherapy independent of BRCA1-like status. EZH2 inhibition improves the antitumor effect of platinum drugs in Brca1-deficient breast tumors in vivo.
Assuntos
Proteína BRCA1/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/tratamento farmacológico , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Neoplasias Mamárias Animais/tratamento farmacológico , Platina/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Proteína BRCA1/metabolismo , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Feminino , Humanos , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Camundongos , Camundongos Knockout , Taxa de Sobrevida , Resultado do TratamentoRESUMO
A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
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The epigenetic writer lysine-specific demethylase 1 (LSD1) is aberrantly upregulated in many cancer types and its overexpression correlates with poor survival and tumor progression. In this study, we analysed LSD1 function in non-small cell lung cancer adenocarcinomas. Expression profiling of 182 cases of lung adenocarcinoma proved a significant correlation of LSD1 overexpression with lung adenocarcinoma progression and metastasis. KRAS-mutated lung cancer cell clones were stably silenced for LSD1 expression. RNA-seq and comprehensive pathway analysis revealed, that genes related to a recently described non-canonical integrin ß3 pathway, were significantly downregulated by LSD1 silencing. Hence, invasion and self-renewal capabilities were strongly decreased. Notably, this novel defined LSD1/integrin ß3 axis, was also detected in human lung adenocarcinoma specimens. Furthermore, the linkage of LSD1 to an altered expression pattern of lung-lineage specific transcription factors and genes, which are involved in alveolar epithelial differentiation, was demonstrated. Thus, our findings point to a LSD1-integrin ß3 axis, conferring attributes of invasiveness and tumor progression to lung adenocarcinoma.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Histona Desmetilases/metabolismo , Integrina beta3/metabolismo , Neoplasias Pulmonares/metabolismo , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Biomarcadores Tumorais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Células Cultivadas , Feminino , Expressão Gênica , Técnicas de Silenciamento de Genes , Histona Desmetilases/genética , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Mutação , NF-kappa B/metabolismo , Gradação de Tumores , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , RNA Mensageiro/genética , Transdução de SinaisRESUMO
KRAS-mutant lung adenocarcinoma is among the most common cancer entities and, in advanced stages, typically displays poor prognosis due to acquired resistance against chemotherapy, which is still largely based on cisplatin-containing combination regimens. Mechanisms of cisplatin resistance have been extensively investigated, and ERCC1 has emerged as a key player due to its central role in the repair of cisplatin-induced DNA lesions. However, clinical data have not unequivocally confirmed ERCC1 status as a predictor of the response to cisplatin treatment. Therefore, we employed an autochthonous mouse model of Kras-driven lung adenocarcinoma resembling human lung adenocarcinoma to investigate the role of Ercc1 in the response to cisplatin treatment. Our data show that Ercc1 deficiency in Tp53-deficient murine lung adenocarcinoma induces a more aggressive tumor phenotype that displays enhanced sensitivity to cisplatin treatment. Furthermore, tumors that relapsed after cisplatin treatment in our model develop a robust etoposide sensitivity that is independent of the Ercc1 status and depends solely on previous cisplatin exposure. Our results provide a solid rationale for further investigation of the possibility of preselection of lung adenocarcinoma patients according to the functional ERCC1- and mutational TP53 status, where functionally ERCC1-incompetent patients might benefit from sequential cisplatin and etoposide chemotherapy. IMPLICATIONS: This study provides a solid rationale for the stratification of lung adenocarcinoma patients according to the functional ERCC1- and mutational TP53 status, where functionally ERCC1-incompetent patients could benefit from sequential cisplatin and etoposide chemotherapy. Mol Cancer Res; 14(11); 1110-23. ©2016 AACR.
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Adenocarcinoma/tratamento farmacológico , Cisplatino/administração & dosagem , Proteínas de Ligação a DNA/deficiência , Endonucleases/deficiência , Neoplasias Pulmonares/tratamento farmacológico , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/genética , Adenocarcinoma/genética , Adenocarcinoma de Pulmão , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Etoposídeo/administração & dosagem , Etoposídeo/farmacologia , Humanos , Neoplasias Pulmonares/genética , Camundongos , Mutação , Medicina de Precisão , Células Tumorais CultivadasRESUMO
Small cell lung cancers (SCLCs) and extrapulmonary small cell cancers (SCCs) are very aggressive tumors arising de novo as primary small cell cancer with characteristic genetic lesions in RB1 and TP53. Based on murine models, neuroendocrine stem cells of the terminal bronchioli have been postulated as the cellular origin of primary SCLC. However, both in lung and many other organs, combined small cell/non-small cell tumors and secondary transitions from non-small cell carcinomas upon cancer therapy to neuroendocrine and small cell tumors occur. We define features of "small cell-ness" based on neuroendocrine markers, characteristic RB1 and TP53 mutations and small cell morphology. Furthermore, here we identify a pathway driving the pathogenesis of secondary SCLC involving inactivating NOTCH mutations, activation of the NOTCH target ASCL1 and canonical WNT-signaling in the context of mutual bi-allelic RB1 and TP53 lesions. Additionally, we explored ASCL1 dependent RB inactivation by phosphorylation, which is reversible by CDK5 inhibition. We experimentally verify the NOTCH-ASCL1-RB-p53 signaling axis in vitro and validate its activation by genetic alterations in vivo. We analyzed clinical tumor samples including SCLC, SCC and pulmonary large cell neuroendocrine carcinomas and adenocarcinomas using amplicon-based Next Generation Sequencing, immunohistochemistry and fluorescence in situ hybridization. In conclusion, we identified a novel pathway underlying rare secondary SCLC which may drive small cell carcinomas in organs other than lung, as well.
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Carcinoma Neuroendócrino/genética , Carcinoma Neuroendócrino/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Transdução de Sinais , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/patologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Análise Mutacional de DNA , Citometria de Fluxo , Imunofluorescência , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Receptores Notch/genética , Receptores Notch/metabolismo , Proteína do Retinoblastoma/genética , Transfecção , Proteína Supressora de Tumor p53/genéticaRESUMO
Small cell lung carcinoma (SCLC) is the most aggressive entity of lung cancer. Rapid cancer progression and early formation of systemic metastases drive the deadly outcome of SCLC. Recent advances in identifying oncogenes by cancer whole genome sequencing improved the understanding of SCLC carcinogenesis. However, tumor material is often limited in the clinic. Thus, it is a compulsive issue to improve SCLC diagnostics by combining established immunohistochemistry and next generation sequencing. We implemented amplicon-based next generation deep sequencing in our routine diagnostics pipeline to analyze RB1, TP53, EP300 and CREBBP, frequently mutated in SCLC. Thereby, our pipeline combined routine SCLC histology and identification of somatic mutations. We comprehensively analyzed fifty randomly collected SCLC metastases isolated from trachea and lymph nodes in comparison to specimens derived from primary SCLC. SCLC lymph node metastases showed enhanced proliferation and frequently a collapsed keratin cytoskeleton compared to SCLC metastases isolated from trachea. We identified characteristic synchronous mutations in RB1 and TP53 and non-synchronous CREBBP and EP300 mutations. Our data showed the benefit of implementing deep sequencing into routine diagnostics. We here identify oncogenic drivers and simultaneously gain further insights into SCLC tumor biology.
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Análise Mutacional de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias Pulmonares/genética , Metástase Neoplásica/genética , Carcinoma de Pequenas Células do Pulmão/genética , Humanos , Neoplasias Pulmonares/patologia , Metástase Neoplásica/diagnóstico , Carcinoma de Pequenas Células do Pulmão/patologiaRESUMO
We have sequenced the genomes of 110 small cell lung cancers (SCLC), one of the deadliest human cancers. In nearly all the tumours analysed we found bi-allelic inactivation of TP53 and RB1, sometimes by complex genomic rearrangements. Two tumours with wild-type RB1 had evidence of chromothripsis leading to overexpression of cyclin D1 (encoded by the CCND1 gene), revealing an alternative mechanism of Rb1 deregulation. Thus, loss of the tumour suppressors TP53 and RB1 is obligatory in SCLC. We discovered somatic genomic rearrangements of TP73 that create an oncogenic version of this gene, TP73Δex2/3. In rare cases, SCLC tumours exhibited kinase gene mutations, providing a possible therapeutic opportunity for individual patients. Finally, we observed inactivating mutations in NOTCH family genes in 25% of human SCLC. Accordingly, activation of Notch signalling in a pre-clinical SCLC mouse model strikingly reduced the number of tumours and extended the survival of the mutant mice. Furthermore, neuroendocrine gene expression was abrogated by Notch activity in SCLC cells. This first comprehensive study of somatic genome alterations in SCLC uncovers several key biological processes and identifies candidate therapeutic targets in this highly lethal form of cancer.
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Genoma Humano/genética , Genômica , Neoplasias Pulmonares/genética , Mutação/genética , Carcinoma de Pequenas Células do Pulmão/genética , Alelos , Animais , Linhagem Celular Tumoral , Pontos de Quebra do Cromossomo , Ciclina D1/genética , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Feminino , Perfilação da Expressão Gênica , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Sistemas Neurossecretores/metabolismo , Sistemas Neurossecretores/patologia , Proteínas Nucleares/genética , Receptores Notch/genética , Receptores Notch/metabolismo , Proteína do Retinoblastoma/genética , Transdução de Sinais/genética , Carcinoma de Pequenas Células do Pulmão/metabolismo , Carcinoma de Pequenas Células do Pulmão/patologia , Proteína Tumoral p73 , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genéticaRESUMO
KRAS is one of the most frequently mutated oncogenes in human cancer. Despite substantial efforts, no clinically applicable strategy has yet been developed to effectively treat KRAS-mutant tumors. Here, we perform a cell-line-based screen and identify strong synergistic interactions between cell-cycle checkpoint-abrogating Chk1- and MK2 inhibitors, specifically in KRAS- and BRAF-driven cells. Mechanistically, we show that KRAS-mutant cancer displays intrinsic genotoxic stress, leading to tonic Chk1- and MK2 activity. We demonstrate that simultaneous Chk1- and MK2 inhibition leads to mitotic catastrophe in KRAS-mutant cells. This actionable synergistic interaction is validated using xenograft models, as well as distinct Kras- or Braf-driven autochthonous murine cancer models. Lastly, we show that combined checkpoint inhibition induces apoptotic cell death in KRAS- or BRAF-mutant tumor cells directly isolated from patients. These results strongly recommend simultaneous Chk1- and MK2 inhibition as a therapeutic strategy for the treatment of KRAS- or BRAF-driven cancers.
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Adenocarcinoma/tratamento farmacológico , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , Proteínas ras/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma de Pulmão , Animais , Pontos de Checagem do Ciclo Celular , Quinase 1 do Ponto de Checagem , Dano ao DNA , Modelos Animais de Doenças , Xenoenxertos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Transplante de Neoplasias , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Células Tumorais CultivadasRESUMO
The histone code reader Spindlin1 (SPIN1) has been implicated in tumorigenesis and tumor growth, but the underlying molecular mechanisms remain poorly understood. Here, we show that reducing SPIN1 levels strongly impairs proliferation and increases apoptosis of liposarcoma cells in vitro and in xenograft mouse models. Combining signaling pathway, genome-wide chromatin binding, and transcriptome analyses, we found that SPIN1 directly enhances expression of GDNF, an activator of the RET signaling pathway, in cooperation with the transcription factor MAZ. Accordingly, knockdown of SPIN1 or MAZ results in reduced levels of GDNF and activated RET explaining diminished liposarcoma cell proliferation and survival. In line with these observations, levels of SPIN1, GDNF, activated RET, and MAZ are increased in human liposarcoma compared to normal adipose tissue or lipoma. Importantly, a mutation of SPIN1 within the reader domain interfering with chromatin binding reduces liposarcoma cell proliferation and survival. Together, our data describe a molecular mechanism for SPIN1 function in liposarcoma and suggest that targeting SPIN1 chromatin association with small molecule inhibitors may represent a novel therapeutic strategy.
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Tecido Adiposo/metabolismo , Proteínas de Ciclo Celular/metabolismo , Lipoma/metabolismo , Lipossarcoma/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas c-ret/metabolismo , Transdução de Sinais , Tecido Adiposo/patologia , Animais , Apoptose , Western Blotting , Proteínas de Ciclo Celular/antagonistas & inibidores , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/imunologia , Proliferação de Células , Imunoprecipitação da Cromatina , Imunofluorescência , Código das Histonas , Humanos , Técnicas Imunoenzimáticas , Imunoprecipitação , Lipoma/genética , Lipoma/patologia , Lipossarcoma/genética , Lipossarcoma/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/imunologia , Fosfoproteínas/antagonistas & inibidores , Fosfoproteínas/genética , Fosfoproteínas/imunologia , Proteínas Proto-Oncogênicas c-ret/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Coelhos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de RNA , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Small cell lung cancer and extrapulmonary small cell carcinomas are the most aggressive type of neuroendocrine carcinomas. Clinical treatment relies on conventional chemotherapy and radiotherapy; relapses are frequent. The PD-1/PD-L1/PD-L2 pathway is a major target of anti-tumour immunotherapy. Aberrant PD-L1 or PD-L2 expression may cause local immune-suppression. Here we investigated expression of PD-1 and its ligands by immunohistochemistry and RNA-seq in small cell carcinomas. PD-L1 and PD-1 protein expression were analysed in 94 clinical cases of small cell carcinomas (61 pulmonary, 33 extrapulmonary) by immunohistochemistry using two different monoclonal antibodies (5H1, E1L3N). RNA expression was profiled by RNA-seq in 43 clinical cases. None of the small cell carcinomas showed PD-L1 protein expression in tumour cells. PD-L1 and PD-1 expression was noticed in the stroma: Using immunohistochemistry, 18.5% of cases (17/92) showed PD-L1 expression in tumour-infiltrating macrophages and 48% showed PD-1 positive lymphocytes (45/94). RNA-seq showed moderate PD-L1 gene expression in 37.2% (16/43). PD-L1 was correlated with macrophage and T-cell markers. The second PD-1 ligand PD-L2 was expressed in 27.9% (12/43) and showed similar correlations. Thus, the PD-1/PD-L1 pathway seems activated in a fraction of small cell carcinomas. The carcinoma cells were negative in all cases, PD-L1 was expressed in tumour-infiltrating macrophages and was correlated with tumour-infiltrating lymphocytes. Patients with stromal PD-L1/PD-L2 expression may respond to anti-PD-1 treatment. Thus, evaluation of the composition of the tumour microenvironment should be included in clinical trials. Besides conventional immunohistochemistry, RNA-seq seems suitable for detection of PD-L1/PD-L2 expression and might prove to be more sensitive.
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Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Carcinoma de Células Pequenas/genética , Carcinoma de Células Pequenas/metabolismo , Tumores Neuroendócrinos/genética , Tumores Neuroendócrinos/metabolismo , Carcinoma de Células Pequenas/patologia , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Linfócitos do Interstício Tumoral/metabolismo , Macrófagos/metabolismo , Metástase Neoplásica , Tumores Neuroendócrinos/patologia , Proteína 2 Ligante de Morte Celular Programada 1/genética , Proteína 2 Ligante de Morte Celular Programada 1/metabolismo , Receptor de Morte Celular Programada 1/genética , Receptor de Morte Celular Programada 1/metabolismo , Análise Serial de TecidosRESUMO
Crizotinib, a selective tyrosine kinase inhibitor (TKI), shows marked activity in patients whose lung cancers harbor fusions in the gene encoding anaplastic lymphoma receptor tyrosine kinase (ALK), but its efficacy is limited by variable primary responses and acquired resistance. In work arising from the clinical observation of a patient with ALK fusion-positive lung cancer who had an exceptional response to an insulin-like growth factor 1 receptor (IGF-1R)-specific antibody, we define a therapeutic synergism between ALK and IGF-1R inhibitors. Similar to IGF-1R, ALK fusion proteins bind to the adaptor insulin receptor substrate 1 (IRS-1), and IRS-1 knockdown enhances the antitumor effects of ALK inhibitors. In models of ALK TKI resistance, the IGF-1R pathway is activated, and combined ALK and IGF-1R inhibition improves therapeutic efficacy. Consistent with this finding, the levels of IGF-1R and IRS-1 are increased in biopsy samples from patients progressing on crizotinib monotherapy. Collectively these data support a role for the IGF-1R-IRS-1 pathway in both ALK TKI-sensitive and ALK TKI-resistant states and provide a biological rationale for further clinical development of dual ALK and IGF-1R inhibitors.
Assuntos
Neoplasias Pulmonares/tratamento farmacológico , Pirazóis/uso terapêutico , Piridinas/uso terapêutico , Receptores Proteína Tirosina Quinases/efeitos dos fármacos , Receptor IGF Tipo 1/efeitos dos fármacos , Quinase do Linfoma Anaplásico , Crizotinibe , Feminino , Técnicas de Silenciamento de Genes , Humanos , Proteínas Substratos do Receptor de Insulina/genética , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/metabolismo , Pessoa de Meia-Idade , Pirazóis/farmacologia , Piridinas/farmacologia , Receptor IGF Tipo 1/metabolismo , Regulação para CimaRESUMO
Pulmonary carcinoids are rare neuroendocrine tumours of the lung. The molecular alterations underlying the pathogenesis of these tumours have not been systematically studied so far. Here we perform gene copy number analysis (n=54), genome/exome (n=44) and transcriptome (n=69) sequencing of pulmonary carcinoids and observe frequent mutations in chromatin-remodelling genes. Covalent histone modifiers and subunits of the SWI/SNF complex are mutated in 40 and 22.2% of the cases, respectively, with MEN1, PSIP1 and ARID1A being recurrently affected. In contrast to small-cell lung cancer and large-cell neuroendocrine lung tumours, TP53 and RB1 mutations are rare events, suggesting that pulmonary carcinoids are not early progenitor lesions of the highly aggressive lung neuroendocrine tumours but arise through independent cellular mechanisms. These data also suggest that inactivation of chromatin-remodelling genes is sufficient to drive transformation in pulmonary carcinoids.
Assuntos
Tumor Carcinoide/genética , Montagem e Desmontagem da Cromatina/genética , Neoplasias Pulmonares/genética , Mutação , Adolescente , Adulto , Idoso , Sequência de Bases , Tumor Carcinoide/patologia , Mapeamento Cromossômico , Variações do Número de Cópias de DNA , Exoma/genética , Feminino , Dosagem de Genes , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Genoma Humano/genética , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Adulto JovemRESUMO
The linker histone H1 is a key player in chromatin organization, yet our understanding of the regulation of H1 functions by post-translational modifications is very limited. We provide here the first functional characterization of H1 acetylation. We show that H1.4K34 acetylation (H1.4K34ac) is mediated by GCN5 and is preferentially enriched at promoters of active genes, where it stimulates transcription by increasing H1 mobility and recruiting a general transcription factor. H1.4K34ac is dynamic during spermatogenesis and marks undifferentiated cells such as induced pluripotent stem (iPS) cells and testicular germ cell tumors. We propose a model for H1.4K34ac as a novel regulator of chromatin function with a dual role in transcriptional activation.
Assuntos
Histonas/metabolismo , Lisina/metabolismo , Ativação Transcricional , Fatores de Transcrição de p300-CBP/metabolismo , Acetilação , Sequência de Aminoácidos , Ciclo Celular/genética , Regulação Neoplásica da Expressão Gênica , Histona Acetiltransferases , Histonas/genética , Humanos , Lisina/genética , Masculino , Dados de Sequência Molecular , Células-Tronco Pluripotentes/metabolismo , Regiões Promotoras Genéticas , Seminoma/genética , Seminoma/metabolismo , Espermatogênese/genética , Fatores Associados à Proteína de Ligação a TATA/metabolismo , Neoplasias Testiculares/genética , Neoplasias Testiculares/metabolismo , Fator de Transcrição TFIID/metabolismo , Sítio de Iniciação de Transcrição , Regulação para CimaRESUMO
The field of molecular diagnostics has improved our understanding of the pathophysiological mechanisms of malignant alteration, especially in lung cancer which remains the leading cause of cancer-related mortality worldwide. The role of the epidermal growth factor receptor (EGFR) and other molecules linked to the EGFR signaling pathway has been extensively studied, and they have become the target of new, specific therapies in lung adenocarcinomas. Similarly, the amplification of the fibroblast growth factor receptor 1 (FGFR1) gene described in squamous cell lung carcinomas has opened new possibilities for molecular targeted therapy. Next generation sequencing (NGS) methods have made possible an even more accurate detection of rare somatic mutations.