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1.
Head Neck Pathol ; 14(2): 330-340, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32124416

RESUMO

Cancer progression can be understood as the result of deregulation of tumors' immune microenvironments. Recent studies of the alterations of microenvironments highlight their significant influence on the prognosis of patients with head and neck squamous cell carcinoma (HNSCC). It is necessary to better characterize tumor-infiltrating lymphocytes by focusing, in particular, on the tumor escape mechanisms from immune surveillance. One of the best described tumor immune system evasion mechanisms is the expression of co-stimulation molecules that constitute so-called "immune checkpoints". These molecules regulate the immune response by either activating or inhibiting its effects. The programmed cell death 1 (PD-1) surface protein is an inhibitory co-stimulation molecule that induces exhaustion of activated T-lymphocytes (TLs, T cells) through binding with its ligands, PD-L1 and PD-L2. Half of HNSCCs exhibit PD-L1 expression with higher expression identified in human papillomavirus (HPV) positive tumors. Numerous studies have shown differences between the microenvironments of HPV+ and HPV- cancers. Notably, infiltrations of exhausted CD4+ PD1+ and CD8+ PD1+ T cells are far higher in the microenvironment of HPV+ tumors. The FDA has approved the use of molecules that target PD-1 for the treatment of HNSCC. The first results of clinical trials with anti-PD-1 blockers in HNSCC show improved patient survival, particularly long-term survival without recurrence. However, discordant results were sometimes observed, and improvements in defining cellular predictive markers are necessary. With the development of immunotherapies, pathologists play a role in the selection of patients who are eligible for specific treatments and assessment of their prognosis in greater detail. An automated, quantitative in situ imaging system that integrates both multispectral imaging and automated slide scanning could be developed in pathology laboratories. The evaluation of PD-L1 expression has only been used to stratify the administration of first-line immunotherapy. The validation of these tests and their routine interpretation is essential. No specific recommendation is adopted for HPV+ HNSCC.

2.
Cancers (Basel) ; 11(11)2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31703394

RESUMO

Gastric cancer (GC) remains a health issue due to the low efficiency of therapies, such as cisplatin. This unsatisfactory situation highlights the necessity of finding factors impacting GC sensibility to therapies. We analyzed the cisplatin pangenomic response in cancer cells and found HDAC4 as a major epigenetic regulator being inhibited. HDAC4 mRNA repression was partly mediated by the cisplatin-induced expression of miR-140. At a functional level, HDAC4 inhibition favored cisplatin cytotoxicity and reduced tumor growth. Inversely, overexpression of HDAC4 inhibits cisplatin cytotoxicity. Importantly, HDAC4 expression was found to be elevated in gastric tumors compared to healthy tissues, and in particular in specific molecular subgroups. Furthermore, mutations in HDAC4 correlate with good prognosis. Pathway analysis of genes whose expression in patients correlated strongly with HDAC4 highlighted DNA damage, p53 stabilization, and apoptosis as processes downregulated by HDAC4. This was further confirmed by silencing of HDAC4, which favored cisplatin-induced apoptosis characterized by cleavage of caspase 3 and induction of proapoptotic genes, such as BIK, in part via a p53-dependent mechanism. Altogether, these results reveal HDAC4 as a resistance factor for cisplatin in GC cells that impacts on patients' survival.

3.
Cancers (Basel) ; 11(10)2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31640284

RESUMO

BACKGROUND: management of head and neck squamous cell carcinomas (HNSCC) include anti-Epidermal Growth Factor Receptor (EGFR) antibodies and radiotherapy, but resistance emerges in most patients. RAS mutations lead to primary resistance to EGFR blockade in metastatic colorectal cancer but are infrequent in HNSCC, suggesting that other mechanisms are implicated. Since hypoxia and Hypoxia Inducible Factor-1 (HIF-1) have been associated with treatment failure and tumor progression, we hypothesized that EGFR/mammalian Target Of Rapamycin (mTOR)/HIF-1 axis inhibition could radiosensitize HNSCC. METHODS: We treated the radiosensitive Cal27 used as control, and radioresistant SQ20B and UD-SCC1 cells, in vivo and in vitro, with rapamycin and cetuximab before irradiation and evaluated tumor progression and clonogenic survival. RESULTS: Rapamycin and cetuximab inhibited the mTOR/HIF-1α axis, and sensitized the SQ20B cell line to EGFR-inhibition. However, concomitant delivery of radiation to SQ20B xenografts increased tumor relapse frequency, despite effective HIF-1 inhibition. Treatment failure was associated with the induction of HIF-2α expression by cetuximab and radiotherapy. Strikingly, SQ20B and UD-SCC1 cells clonogenic survival dropped <30% after HIF-2α silencing, suggesting a HIF-2-dependent mechanism of oncogenic addiction. CONCLUSIONS: altogether, our data suggest that resistance to EGFR inhibition combined with radiotherapy in HNSCC may depend on tumor HIF-2 expression and underline the urgent need to develop novel HIF-2 targeted treatments.

4.
Cancers (Basel) ; 11(6)2019 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-31181806

RESUMO

The management of locally advanced head and neck squamous cell carcinoma (HNSCC) with Cetuximab, a monoclonal antibody targeting the epidermal growth factor receptor (EGFR), achieves only moderate response rates, and clinical trials that evaluated EGFR-blockade with tyrosine kinase inhibitors (TKI) yielded disappointing results. Inter-tumor heterogeneity may hinder the therapeutic efficiency of anti-EGFR treatments. HNSCC heterogeneity was addressed in several studies, which all converged towards the definition of molecular subgroups. They include the basal subgroup, defined by the deregulated expression of factors involved in the EGFR signaling pathway, including the epiregulin EGFR ligand encoded by the EREG gene. These observations indicate that basal tumors could be more sensitive to anti-EGFR treatments. To test this hypothesis, we performed a screen of a representative collection of basal versus non-basal HNSCC cell lines for their sensitivity to several anti-EGFR drugs (Cetuximab, Afatinib, and Gefitinib), tested as monotherapy or in combination with drugs that target closely-linked pathways [Mitogen-activated protein kinase kinase/ extracellular signal-regulated kinases (MEK), mammalian Target of Rapamycine (mTOR) or Human Epidermal growth factor Receptor 2 (HER2)]. Basal-like cell lines were found to be more sensitive to EGFR blockade alone or in combination with treatments that target MEK, mTOR, or HER2. Strikingly, the basal-like status was found to be a better predictor of cell response to EGFR blockade than clinically relevant mutations [e.g., cyclin-dependent kinase Inhibitor 2A (CDKN2A)]. Interestingly, we show that EGFR blockade inhibits EREG expression, and that EREG knock-down decreases basal cell clonogenic survival, suggesting that EREG expression could be a predictive functional marker of sensitivity to EGFR blockade in basal-like HNSCC.

5.
Sci Rep ; 9(1): 5938, 2019 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-30976051

RESUMO

High-risk Human Papillomavirus infections are responsible for anogenital and oropharyngeal cancers. Alternative splicing is an important mechanism controlling HPV16 gene expression. Modulation in the splice pattern leads to polycistronic HPV16 early transcripts encoding a full length E6 oncoprotein or truncated E6 proteins, commonly named E6*. Spliced E6*I transcripts are the most abundant RNAs produced in HPV-related cancers. To date, the biological function of the E6*I isoform remains controversial. In this study, we identified, by RNA sequencing, cellular targets deregulated by E6*I, among which genes related to ROS metabolism. Concomitantly, E6*I-overexpressing cells display high levels of ROS. However, co-overexpression of both E6 and E6*I has no effect on ROS production. In HPV16-infected cells expressing different E6/E6*I levels, we show that the newly identified targets CCL2 and RAC2 are increased by E6*I but decreased by E6 expression, suggesting that E6 abrogates the effect of E6*I. Taken together, these data support the idea that E6*I acts independently of E6 to increase ROS production and that E6 has the ability to counteract the effects of E6*I. This asks the question of how E6*I can be considered separately of E6 in the natural history of HPV16 infection.

6.
Cancer Lett ; 440-441: 145-155, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30339780

RESUMO

Targeting specific tumor metabolic needs represents an actively investigated therapeutic strategy to bypass tumor resistance mechanisms. In this study, we describe an original approach to impact the cancer metabolism by exploiting the redox properties of a ruthenium organometallic compound. This organometallic complex induced p53-independent cytotoxicity and reduced size and vascularization of patients-derived tumor explants that are resistant to platinum drugs. At the molecular level, the ruthenium complex altered redox enzyme activities and the intracellular redox state by increasing the NAD+/NADH ratio and ROS levels. Pathway analysis pointed to HIF-1 as a top deregulated metabolite pathway. Unlike cisplatin, treatment with the ruthenium complex decreased HIF1A protein levels and expression of HIF1A target genes. The rapid downregulation of HIF1A protein levels involved a direct interaction of the ruthenium compound with the redox enzyme PHD2, a HIF1A master regulator. HIF1A inhibition led to decreased angiogenesis in patient-derived xenografted using fragments of primary human colon tumors. Altogether, our results show that a ruthenium compound impacts metabolic pathways acting as anticancer agents in colon cancer via an original mechanism of action that affects redox enzymes differently than platinum-based drugs.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Compostos Organometálicos/farmacologia , Rutênio/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Neoplasias Colorretais/irrigação sanguínea , Feminino , Células HCT116 , Células Endoteliais da Veia Umbilical Humana , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Compostos Organometálicos/química , Oxirredução , Rutênio/química , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Oncotarget ; 9(101): 37581-37588, 2018 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-30680071

RESUMO

Background: The EXTREME protocol is the standard of care for recurrent or metastatic head and neck squamous-cell carcinoma (R/M HNSCC) in first line. Beyond the first-line except immunotherapy, poor efficacy was reported by second-line chemotherapy. Re-challenge strategies based on a repetition of the first line with platinum and cetuximab regimens might have been an option to consider. Methods: We performed a retrospective study in order to assess the efficacy of the cetuximab plus platinum doublet-based chemotherapy regimen in patients with R/M HNSCC progressing after at least 3 months of cetuximab maintenance (EXTREME protocol). We complete a retrospective review of all medical records from R/M HNSCC patients treated after 16 weeks with the EXTREME regimen and treated with a re-challenge strategy between January 2010 and December 2014 in our institution (Centre Paul Strauss, Strasbourg, France). Results: 33 patients were identified. The re-challenged strategy provided an ORR in 33.3% of cases and a DCR of 69.6% of cases. The median OS and PFS observed from the second line were 11.2 months and 6.5 months for the subset re-challenged by EXTREME or PCC regimens respectively. The response rate between patients with a platin free interval within 3 and 6 months and greater than 6 months were equal. Drugs dose intensity were better with the PCC protocol than the EXTREME regimen used as a rechallenge. Conclusions: This study suggest re-challenging strategy by these regimens could be considered beyond the first line as an option when the platin free interval is greater than 3 months.

8.
Eur J Cancer ; 78: 105-115, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28437708

RESUMO

Human papillomavirus (HPV)-driven oropharyngeal cancers (OPCs) represent an increasing proportion of head and neck cancers that could become, in the next few decades, a public health problem in certain western countries. This significant epidemiological change strongly calls for preventive measures. Prophylactic HPV vaccination and screening programmes for early identification and treatment of premalignant lesions are currently being used to reduce the incidence of uterine cervical cancer, which is the paradigm of HPV-driven malignancy. These strategies have proven to be efficient as the incidence of cervical cancer has dramatically dropped since the 1960s in most countries where they are properly applied. The success of cervical cancer prevention encourages the development of similar approaches to prevent HPV-driven OPCs. However, a number of important limitations impede their application to HPV-driven OPCs, and the development of innovative and specific strategies dedicated to this disease are urgently needed. This article provides an overview on primary, secondary and tertiary prevention of HPV-driven OPC and discusses some directions for future research.


Assuntos
Neoplasias de Cabeça e Pescoço/prevenção & controle , Infecções por Papillomavirus/prevenção & controle , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/metabolismo , DNA Viral/metabolismo , Detecção Precoce de Câncer/métodos , Feminino , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Papillomaviridae/genética , Vacinas contra Papillomavirus , Prevenção Primária/métodos , Medição de Risco , Prevenção Secundária/métodos , Prevenção Terciária/métodos , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/virologia , Vacinação/estatística & dados numéricos , Adulto Jovem
9.
Oncotarget ; 6(39): 41884-901, 2015 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-26474461

RESUMO

Distant metastases arise in 20-30% of patients with squamous cell carcinoma of the head and neck (HNSCC) in the 2 years following treatment. Therapeutic options are limited and the outcome of the patients is poor. The identification of predictive biomarkers of patient at risk for distant metastasis and therapies are urgently needed. We previously identified a clinical subgroup, called "R1" characterized by high propensity for rapid distant metastasis. Here, we showed that "R1" patients do not or at very low level express caveolin-1 (Cav1). Low or no expression of Cav1 is of bad prognosis. Disappearance of Cav1 enables cells to undergo epithelial-mesenchymal transition (EMT). EMT is associated with enhanced migration and invasion. Our study uncovered a new target, α5ß1 integrin. Targeting α5ß1 integrins might not only prevent metastasis of HNSCC but also delay the development of the primary tumor by reducing tumor cell viability. Cav1 detection might be taken into consideration in the future in the clinic not only to identify patients at high risk of metastasis but also to select patient who might benefit from an anti-integrin therapy.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Caveolina 1/metabolismo , Movimento Celular , Transição Epitelial-Mesenquimal , Neoplasias de Cabeça e Pescoço/metabolismo , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/secundário , Carcinoma de Células Escamosas/terapia , Caveolina 1/genética , Linhagem Celular Tumoral , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Integrina alfa5beta1/metabolismo , Estimativa de Kaplan-Meier , Prognóstico , Interferência de RNA , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço , Fatores de Tempo , Transfecção
10.
Oral Oncol ; 51(9): 848-56, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26121938

RESUMO

OBJECTIVES: Human Papillomavirus (HPV)-related oropharyngeal squamous cell carcinoma (OSCC) patients have improved prognosis compared to other head and neck (HNSCC) cancers. Since poor prognosis is associated with tumour hypoxia, we studied whether the hypoxic response is different in HPV-related cells and tumours. MATERIAL AND METHODS: HPV-positive and -negative cells were incubated in hypoxia and analyzed by qRTPCR, western blotting and cell proliferation assays. Tumours formed by xenografting these cells in nude mice were studied by IHC. HNSCC patient samples were analyzed by unsupervised clustering of hypoxia-related gene expression, quantitative real-time PCR (qRTPCR) and immunohistochemical (IHC) detection of neo-blood vessels. RESULTS AND CONCLUSION: HPV-positive and -negative cells responded differently to hypoxia, in terms of gene expression (HIF-1α, PHD-3, GLUT-1 and VEGF-A) and cell survival. Tumour xenografts formed by HPV-positive cells had fewer hypoxic areas than those formed by HPV-negative cells. HPV related tumours were less hypoxic, expressed lower levels of hypoxia-responsive genes, and had a higher density of neo-blood vessels. HPV-related OSCC display lower tumour hypoxia, which could be linked to the distinct intrinsic abilities of HPV-positive tumour cells to adapt to hypoxia and to their better prognosis.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Orofaríngeas/metabolismo , Infecções por Papillomavirus/metabolismo , Animais , Western Blotting , Hipóxia Celular/fisiologia , Sobrevivência Celular/fisiologia , Feminino , Expressão Gênica/fisiologia , Humanos , Masculino , Camundongos , Camundongos Nus , Reação em Cadeia da Polimerase em Tempo Real
11.
BMC Syst Biol ; 9: 28, 2015 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-26080803

RESUMO

BACKGROUND: Estrogen receptor alpha36 (ERalpha36), a variant of estrogen receptor alpha (ER) is expressed in about half of breast tumors, independently of the [ER+]/[ER-] status. In vitro, ERalpha36 triggers mitogenic non-genomic signaling and migration ability in response to 17beta-estradiol and tamoxifen. In vivo, highly ERalpha36 expressing tumors are of poor outcome especially as [ER+] tumors are submitted to tamoxifen treatment which, in turn, enhances ERalpha36 expression. RESULTS: Our study aimed to validate ERalpha36 expression as a reliable prognostic factor for cancer progression from an estrogen dependent proliferative tumor toward an estrogen dispensable metastatic disease. In a retrospective study, we tried to decipher underlying mechanisms of cancer progression by using an original modeling of the relationships between ERalpha36, other estrogen and growth factor receptors and metastatic marker expression. Nonlinear correlation analyses and mutual information computations led to characterize a complex network connecting ERalpha36 to either non-genomic estrogen signaling or to metastatic process. CONCLUSIONS: This study identifies ERalpha36 expression level as a relevant classifier which should be taken into account for breast tumors clinical characterization and [ER+] tumor treatment orientation, using a generic approach for the rapid, cheap and relevant evaluation of any candidate gene expression as a predictor of a complex biological process.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Biologia Computacional/métodos , Progressão da Doença , Receptor alfa de Estrogênio/genética , Variação Genética , Neoplasias da Mama/classificação , Neoplasias da Mama/patologia , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Metástase Neoplásica , Prognóstico
12.
PLoS One ; 9(11): e113050, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25401928

RESUMO

The molecular response to hypoxia is a critical cellular process implicated in cancer, and a target for drug development. The activity of the major player, HIF1α, is regulated at different levels by various factors, including the transcription factor ELK3. The molecular mechanisms of this intimate connection remain largely unknown. Whilst investigating global ELK3-chromatin interactions, we uncovered an unexpected connection that involves the microRNA hsa-miR-155-5p, a hypoxia-inducible oncomir that targets HIF1α. One of the ELK3 chromatin binding sites, detected by Chromatin Immuno-Precipitation Sequencing (ChIP-seq) of normal Human Umbilical Vein Endothelial Cells (HUVEC), is located at the transcription start site of the MIR155HG genes that expresses hsa-miR-155-5p. We confirmed that ELK3 binds to this promoter by ChIP and quantitative polymerase chain reaction (QPCR). We showed that ELK3 and hsa-miR-155-5p form a double-negative regulatory loop, in that ELK3 depletion induced hsa-miR-155-5p expression and hsa-miR-155-5p expression decreased ELK3 expression at the RNA level through a conserved target sequence in its 3'-UTR. We further showed that the activities of hsa-miR-155-5p and ELK3 are functionally linked. Pathway analysis indicates that both factors are implicated in related processes, including cancer and angiogenesis. Hsa-miR-155-5p expression and ELK3 depletion have similar effects on expression of known ELK3 target genes, and on in-vitro angiogenesis and wound closure. Bioinformatic analysis of cancer RNA-seq data shows that hsa-miR-155-5p and ELK3 expression are significantly anti-correlated, as would be expected from hsa-miR-155-5p targeting ELK3 RNA. Finally, hypoxia (0% oxygen) down-regulates ELK3 mRNA in a microRNA and hsa-miR-155-5p dependent manner. These results tie ELK3 into the hypoxia response pathway through an oncogenic microRNA and into a circuit implicated in the dynamics of the hypoxic response. This crosstalk could be important for the development of new treatments for a range of pathologies.


Assuntos
Hipóxia/genética , MicroRNAs/genética , Proteínas Proto-Oncogênicas/genética , Interferência de RNA , Fatores de Transcrição/genética , Regiões 3' não Traduzidas , Animais , Sequência de Bases , Sítios de Ligação , Linhagem Celular , Cromatina/metabolismo , Imunoprecipitação da Cromatina , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Camundongos , MicroRNAs/química , Matrizes de Pontuação de Posição Específica , Ligação Proteica , Proteínas Proto-Oncogênicas/metabolismo , RNA Mensageiro/química , RNA Mensageiro/genética , Fatores de Transcrição/metabolismo
14.
Clin Cancer Res ; 19(15): 4174-84, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23757353

RESUMO

PURPOSE: Distant metastasis after treatment is observed in about 20% of squamous cell carcinoma of the head and neck (HNSCC). In the absence of any validated robust biomarker, patients at higher risk for metastasis cannot be provided with tailored therapy. To identify prognostic HNSCC molecular subgroups and potential biomarkers, we have conducted genome-wide integrated analysis of four omic sets of data. EXPERIMENTAL DESIGN: Using state-of-the-art technologies, a core set of 45 metastasizing and 55 nonmetastasizing human papillomavirus (HPV)-unrelated HNSCC patient samples were analyzed at four different levels: gene expression (transcriptome), DNA methylation (methylome), DNA copy number (genome), and microRNA (miRNA) expression (miRNome). Molecular subgroups were identified by a model-based clustering analysis. Their clinical relevance was evaluated by survival analysis, and functional significance by pathway enrichment analysis. RESULTS: Patient subgroups selected by transcriptome, methylome, or miRNome integrated analysis are associated with shorter metastasis-free survival (MFS). A common subgroup, R1, selected by all three omic approaches, is statistically more significantly associated with MFS than any of the single omic-selected subgroups. R1 and non-R1 samples display similar DNA copy number landscapes, but more frequent chromosomal aberrations are observed in the R1 cluster (especially loss at 13q14.2-3). R1 tumors are characterized by alterations of pathways involved in cell-cell adhesion, extracellular matrix (ECM), epithelial-to-mesenchymal transition (EMT), immune response, and apoptosis. CONCLUSIONS: Integration of data across several omic profiles leads to better selection of patients at higher risk, identification of relevant molecular pathways of metastasis, and potential to discover biomarkers and drug targets.


Assuntos
Carcinoma de Células Escamosas/genética , Metilação de DNA/genética , Neoplasias de Cabeça e Pescoço/genética , MicroRNAs/genética , Metástase Neoplásica/genética , Transcriptoma/genética , Adulto , Idoso , Apoptose/genética , Biomarcadores Tumorais , Carcinoma de Células Escamosas/patologia , Variações do Número de Cópias de DNA/genética , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Terapia de Alvo Molecular , Metástase Neoplásica/patologia , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço
15.
Cancer Res ; 73(16): 5040-52, 2013 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-23774208

RESUMO

The DNA repair protein damaged DNA-binding 2 (DDB2) has been implicated in promoting cell-cycle progression by regulating gene expression. DDB2 is selectively overexpressed in breast tumor cells that are noninvasive, but not in those that are invasive. We found that its overexpression in invasive human breast tumor cells limited their motility and invasiveness in vitro and blocked their ability to colonize lungs in vivo, defining a new function for DDB2 in malignant progression. DDB2 overexpression attenuated the activity of NF-κB and the expression of its target matrix metalloprotease 9 (MMP9). Mechanistic investigations indicated that DDB2 decreased NF-κB activity by upregulating expression of IκBα by binding the proximal promoter of this gene. This effect was causally linked to invasive capacity. Indeed, knockdown of DDB2-induced IκBα gene expression restored NF-κB activity and MMP9 expression, along with the invasive properties of breast tumor cells overexpressing DDB2. Taken together, our findings enlighten understanding of how breast cancer cells progress to an invasive phenotype and underscore potential clinical interest in DDB2 as a prognostic marker or therapeutic target in this setting.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , NF-kappa B/genética , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Feminino , Humanos , Proteínas I-kappa B/genética , Proteínas I-kappa B/metabolismo , Células MCF-7 , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Inibidor de NF-kappaB alfa , NF-kappa B/metabolismo , Invasividade Neoplásica , Prognóstico , Regiões Promotoras Genéticas , Transcrição Genética , Regulação para Cima/genética
17.
Int J Cancer ; 132(2): E26-36, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22890882

RESUMO

Patients with human papillomavirus (HPV)-related oropharyngeal tumors display improved prognosis. The biological basis of this tumor phenotype is poorly understood. We investigated whether increased lymphocyte infiltrate in HPV-positive oropharyngeal squamous cell carcinomas could account for better prognosis. We previously identified, in an Affymetrix GeneChip analysis of 83 HPV-unrelated and 11 HPV-related squamous cell carcinoma of the oropharynx, several candidate genes, including CD8α and CD3ζ. Their expression was validated in this study by qRT-PCR on an independent clinical series of 144 oropharyngeal tumors. Immunohistochemical staining of tumor specimens was performed to evaluate infiltration of tumor stroma by CD8+ and CD4+ lymphocytes. The prognostic value of CD8α and CD3ζ expression levels was measured by Kaplan-Meier and Cox regression model analyses. Immune response-related signaling pathways were found to be deregulated in HPV-positive oropharyngeal tumors. Expression of CD8α, CD3ζ, granzyme K, CD28 and integrin αL RNAs was upregulated in HPV-positive lesions when compared with HPV-unrelated tumors (p < 0.05). Stroma of HPV-positive tumors was frequently and strongly infiltrated by CD8α- and CD3ζ-positive T cells. CD8α RNA expression correlated with both improved global (Kaplan-Meier; p = 0.005; Cox regression: p = 0.003) and disease-free (Cox regression: p = 0.04) survival. CD3ζ RNA expression correlated with improved overall survival (Cox regression: p = 0.024). These results suggest that an increased cytotoxic T-cell-based antitumor immune response is involved in improved prognosis of patients with HPV-positive tumors.


Assuntos
Antígenos CD8/metabolismo , Linfócitos T CD8-Positivos/imunologia , Carcinoma de Células Escamosas/imunologia , Neoplasias Orofaríngeas/imunologia , Infecções por Papillomavirus/imunologia , Alphapapillomavirus/genética , Complexo CD3/genética , Complexo CD3/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/virologia , Intervalo Livre de Doença , Feminino , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Imunidade Celular/genética , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/metabolismo , Neoplasias Orofaríngeas/mortalidade , Neoplasias Orofaríngeas/patologia , Neoplasias Orofaríngeas/virologia , Infecções por Papillomavirus/mortalidade , Infecções por Papillomavirus/patologia , Infecções por Papillomavirus/virologia , Prognóstico , Modelos de Riscos Proporcionais , Análise de Regressão , Transcriptoma , Microambiente Tumoral
18.
Int J Oncol ; 41(4): 1531-40, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22895816

RESUMO

Human papillomavirus (HPV)-related oropharyngeal cancer represents a distinct head and neck squamous cell carcinoma (HNSCC) subpopulation, with improved disease-free and overall survival. In general, HPV-positive HNSCCs express wild-type TP53, which could explain its increased radiosensitivity. However, the molecular mechanisms underlying this higher sensitivity remain elusive. We have previously shown that HPV-related oropharyngeal carcinomas express decreased levels of the NEDD8-activating enzyme 1/amyloid ß precursor protein-binding protein 1 (NAE1/APP-BP1) gene. NAE1/APP-BP1 function is required for the NEDDylation of target proteins, and has been shown to be a negative regulator of p53 transcriptional activity. In this study, we addressed the hypothesis that NAE1/APP-BP1 expression levels regulate p53 activity and cell survival upon ionizing irradiation. We used the radiosensitive and naturally HPV16-infected UPCI:SCC90 cell line and the radioresistant and HPV-negative SQ20B cell line as the control. NAE1/APP-BP1 expression levels were modulated with expression constructs and siRNAs. Radiosensitivity was evaluated with clonogenic survival assays. p53 transcriptional activity was measured with a luciferase assay. The overexpression of NAE1/APP-BP1 in UPCI:SCC90 cells resulted in the increased NEDDylation of p53, inhibition of p53 activity and increased cell resistance to ionizing radiation. Conversely, the inhibition of NAE1/APP-BP1 expression in SQ20B cells induced p53-dependent cell death after treatment with X-rays. Taken together, these results indicate that NAE1/APP-BP1 and NEDDylation are invovled in modulating p53 activity and regulating its role in the response of cells to ionizing radiation. Our findings bring new insights in the molecular mechanisms underlying the increased radiosensitivity of HPV-related oropharyngeal tumors. This is of importance, as no reliable and robust predictive biomarkers for tumor response to radiotherapy are currently available. These results also have potential clinical significance, as drugs targeting NAE1/APP-BP1 have recently emerged as a novel therapeutic modality in cancer treatment.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Proteínas de Ligação a DNA/genética , Neoplasias de Cabeça e Pescoço/radioterapia , Proteína Supressora de Tumor p53/genética , Ubiquitinas/genética , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Papillomavirus Humano 16/patogenicidade , Humanos , Proteína NEDD8 , Tolerância a Radiação/genética , Radiação Ionizante , Radiossensibilizantes , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/efeitos da radiação , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/efeitos da radiação , Proteína Supressora de Tumor p53/metabolismo , Ubiquitinas/metabolismo
19.
PLoS One ; 5(4): e10245, 2010 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-20422006

RESUMO

BACKGROUND: Endocytosis is a key regulatory step of diverse signalling pathways, including receptor tyrosine kinase (RTK) signalling. Hrs and Stam constitute the ESCRT-0 complex that controls the initial selection of ubiquitinated proteins, which will subsequently be degraded in lysosomes. It has been well established ex vivo and during Drosophila embryogenesis that Hrs promotes EGFR down regulation. We have recently isolated the first mutations of stam in flies and shown that Stam is required for air sac morphogenesis, a larval respiratory structure whose formation critically depends on finely tuned levels of FGFR activity. This suggest that Stam, putatively within the ESCRT-0 complex, modulates FGF signalling, a possibility that has not been examined in Drosophila yet. PRINCIPAL FINDINGS: Here, we assessed the role of the Hrs/Stam complex in the regulation of signalling activity during Drosophila development. We show that stam and hrs are required for efficient FGFR signalling in the tracheal system, both during cell migration in the air sac primordium and during the formation of fine cytoplasmic extensions in terminal cells. We find that stam and hrs mutant cells display altered FGFR/Btl localisation, likely contributing to impaired signalling levels. Electron microscopy analyses indicate that endosome maturation is impaired at distinct steps by hrs and stam mutations. These somewhat unexpected results prompted us to further explore the function of stam and hrs in EGFR signalling. We show that while stam and hrs together downregulate EGFR signalling in the embryo, they are required for full activation of EGFR signalling during wing development. CONCLUSIONS/SIGNIFICANCE: Our study shows that the ESCRT-0 complex differentially regulates RTK signalling, either positively or negatively depending on tissues and developmental stages, further highlighting the importance of endocytosis in modulating signalling pathways during development.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Proteínas de Drosophila/fisiologia , Desenvolvimento Embrionário , Complexos Endossomais de Distribuição Requeridos para Transporte/fisiologia , Fosfoproteínas/fisiologia , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Regulação para Baixo , Drosophila/crescimento & desenvolvimento , Proteínas de Drosophila/genética , Endocitose , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Endossomos , Mutação , Fosfoproteínas/genética , Transporte Proteico , Receptores de Fatores de Crescimento de Fibroblastos/metabolismo
20.
Anticancer Res ; 30(2): 303-10, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20332433

RESUMO

The aim of the present study was to determine the cytotoxic consequences of high-linear energy transfer (LET) irradiation in the presence of oxaliplatin on hepatocellular carcinoma (HCC) cells in vitro. We attempted to correlate the induction of apoptosis and autophagy with the formation of DNA double-strand breaks (DSBs). SK-Hep1 cells were irradiated by 65 MeV neutrons in the presence of oxaliplatin and/or the poly(ADP-ribose) polymerase (PARP) inhibitor PJ34. DSBs were measured by the formation of gammaH2AX foci. Results show that in SK-Hep1 cells exposed to fast neutrons in the presence of oxaliplatin, DSBs occurred and persisted with time after irradiation. While apoptosis remained low in co-treated cells, autophagy was considerably increased after irradiation and augmented by the addition of oxaliplatin. Thus, autophagic cell death appears to play a prominent role in the cytotoxicity of the combined treatment and may be linked to the generation of heavy damage to DNA.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Carcinoma Hepatocelular/patologia , Transferência Linear de Energia , Neoplasias Hepáticas/patologia , Compostos Organoplatínicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/radioterapia , Linhagem Celular Tumoral , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/efeitos da radiação , Histonas/metabolismo , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/radioterapia , Nêutrons , Oxaliplatina , Poli(ADP-Ribose) Polimerases/metabolismo
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