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1.
Nat Methods ; 19(7): 893-898, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35739310

RESUMO

Bioluminescence imaging with luciferase-luciferin pairs is a well-established technique for visualizing biological processes across tissues and whole organisms. Applications at the microscale, by contrast, have been hindered by a lack of detection platforms and easily resolved probes. We addressed this limitation by combining bioluminescence with phasor analysis, a method commonly used to distinguish spectrally similar fluorophores. We built a camera-based microscope equipped with special optical filters to directly assign phasor locations to unique luciferase-luciferin pairs. Six bioluminescent reporters were easily resolved in live cells, and the readouts were quantitative and instantaneous. Multiplexed imaging was also performed over extended time periods. Bioluminescent phasor further provided direct measures of resonance energy transfer in single cells, setting the stage for dynamic measures of cellular and molecular features. The merger of bioluminescence with phasor analysis fills a long-standing void in imaging capabilities, and will bolster future efforts to visualize biological events in real time and over multiple length scales.


Assuntos
Medições Luminescentes , Microscopia , Luciferases , Medições Luminescentes/métodos
2.
EMBO J ; 33(9): 1027-43, 2014 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-24674967

RESUMO

During the stress response to intense exercise, the sympathetic nervous system (SNS) induces rapid catabolism of energy reserves through the release of catecholamines and subsequent activation of protein kinase A (PKA). Paradoxically, chronic administration of sympathomimetic drugs (ß-agonists) leads to anabolic adaptations in skeletal muscle, suggesting that sympathetic outflow also regulates myofiber remodeling. Here, we show that ß-agonists or catecholamines released during intense exercise induce Creb-mediated transcriptional programs through activation of its obligate coactivators Crtc2 and Crtc3. In contrast to the catabolic activity normally associated with SNS function, activation of the Crtc/Creb transcriptional complex by conditional overexpression of Crtc2 in the skeletal muscle of transgenic mice fostered an anabolic state of energy and protein balance. Crtc2-overexpressing mice have increased myofiber cross-sectional area, greater intramuscular triglycerides and glycogen content. Moreover, maximal exercise capacity was enhanced after induction of Crtc2 expression in transgenic mice. Collectively these findings demonstrate that the SNS-adrenergic signaling cascade coordinates a transient catabolic stress response during high-intensity exercise, which is followed by transcriptional reprogramming that directs anabolic changes for recovery and that augments subsequent exercise performance.


Assuntos
Tolerância ao Exercício/genética , Músculo Esquelético/metabolismo , Sistema Nervoso Simpático/metabolismo , Fatores de Transcrição/fisiologia , Animais , Animais Recém-Nascidos , Catecolaminas/metabolismo , Catecolaminas/farmacologia , Células Cultivadas , Tolerância ao Exercício/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Condicionamento Físico Animal/fisiologia
3.
Proc Natl Acad Sci U S A ; 111(32): E3260-8, 2014 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-25071166

RESUMO

Chimeric oncoproteins created by chromosomal translocations are among the most common genetic mutations associated with tumorigenesis. Malignant mucoepidermoid salivary gland tumors, as well as a growing number of solid epithelial-derived tumors, can arise from a recurrent t (11, 19)(q21;p13.1) translocation that generates an unusual chimeric cAMP response element binding protein (CREB)-regulated transcriptional coactivator 1 (CRTC1)/mastermind-like 2 (MAML2) (C1/M2) oncoprotein comprised of two transcriptional coactivators, the CRTC1 and the NOTCH/RBPJ coactivator MAML2. Accordingly, the C1/M2 oncoprotein induces aberrant expression of CREB and NOTCH target genes. Surprisingly, here we report a gain-of-function activity of the C1/M2 oncoprotein that directs its interactions with myelocytomatosis oncogene (MYC) proteins and the activation of MYC transcription targets, including those involved in cell growth and metabolism, survival, and tumorigenesis. These results were validated in human mucoepidermoid tumor cells that harbor the t (11, 19)(q21;p13.1) translocation and express the C1/M2 oncoprotein. Notably, the C1/M2-MYC interaction is necessary for C1/M2-driven cell transformation, and the C1/M2 transcriptional signature predicts other human malignancies having combined involvement of MYC and CREB. These findings suggest that such gain-of-function properties may also be manifest in other oncoprotein fusions found in human cancer and that agents targeting the C1/M2-MYC interface represent an attractive strategy for the development of effective and safe anticancer therapeutics in tumors harboring the t (11, 19) translocation.


Assuntos
Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Animais , Linhagem Celular , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Cromossomos Humanos Par 1/genética , Cromossomos Humanos Par 19/genética , Proteínas de Ligação a DNA/química , Redes Reguladoras de Genes , Genes myc , Células HEK293 , Humanos , Camundongos , Tumor Mucoepidermoide/genética , Tumor Mucoepidermoide/metabolismo , Células NIH 3T3 , Proteínas Nucleares/química , Proteínas de Fusão Oncogênica/química , Domínios e Motivos de Interação entre Proteínas , Ratos , Neoplasias das Glândulas Salivares/genética , Neoplasias das Glândulas Salivares/metabolismo , Transativadores , Fatores de Transcrição/química , Translocação Genética
4.
Nature ; 466(7303): 197-202, 2010 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-20613834

RESUMO

Cocaine addiction is characterized by a gradual loss of control over drug use, but the molecular mechanisms regulating vulnerability to this process remain unclear. Here we report that microRNA-212 (miR-212) is upregulated in the dorsal striatum of rats with a history of extended access to cocaine. Striatal miR-212 decreases responsiveness to the motivational properties of cocaine by markedly amplifying the stimulatory effects of the drug on cAMP response element binding protein (CREB) signalling. This action occurs through miR-212-enhanced Raf1 activity, resulting in adenylyl cyclase sensitization and increased expression of the essential CREB co-activator TORC (transducer of regulated CREB; also known as CRTC). Our findings indicate that striatal miR-212 signalling has a key role in determining vulnerability to cocaine addiction, reveal new molecular regulators that control the complex actions of cocaine in brain reward circuitries and provide an entirely new direction for the development of anti-addiction therapeutics based on the modulation of noncoding RNAs.


Assuntos
Transtornos Relacionados ao Uso de Cocaína/genética , Transtornos Relacionados ao Uso de Cocaína/metabolismo , Cocaína/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , MicroRNAs/metabolismo , Neostriado/metabolismo , Transdução de Sinais , Adenilil Ciclases/metabolismo , Animais , Cocaína/farmacologia , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Transtornos Relacionados ao Uso de Cocaína/enzimologia , MAP Quinase Quinase Quinases/metabolismo , Masculino , MicroRNAs/biossíntese , MicroRNAs/genética , Neostriado/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-raf , Ratos , Ratos Wistar , Recompensa , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos
5.
J Orthop Traumatol ; 17(1): 89-93, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26156225

RESUMO

UNLABELLED: The purpose of this brief paper is to present the preliminary results of a modified Austin/chevron osteotomy for treatment of hallux valgus and hallux rigidus. In this procedure, the dorsal arm of the osteotomy is performed orthogonal to the horizontal plane of the first metatarsal, the main advantage being that this allows much easier and more accurate multiplanar correction of first metatarsal deformities. From 2010 to 2013, 184 consecutive patients with symptomatic hallux valgus and 48 patients with hallux rigidus without severe metatarsophalangeal joint degeneration underwent such modified chevron osteotomy. Mean patient age was 54.9 (range 21-70) years, and mean follow-up duration was 41.7 (range 24-56) months. Ninety-three percent of patients were satisfied with the surgery. Mean American Orthopaedic Foot and Ankle Society (AOFAS) score improved from 56.6 preoperatively to 90.6 at last follow-up, and mean visual analog scale (VAS) pain score decreased from 5.7 preoperatively to 1.6 at final follow-up (p < 0.05). In patients treated for hallux valgus, mean hallux valgus angle decreased from 34.1° preoperatively to 6.2° at final follow-up, and mean intermetatarsal angle decreased from 18.5° preoperatively to 4.1° at final follow-up (p < 0.05). One patient developed postoperative transfer metatarsalgia, treated successfully with second-time percutaneous osteotomy of the minor metatarsals, whilst one patient had wound infection that resolved with systemic antibiotics. LEVEL OF EVIDENCE: Level IV.


Assuntos
Hallux Rigidus/cirurgia , Hallux Valgus/cirurgia , Ossos do Metatarso/cirurgia , Articulação Metatarsofalângica/fisiopatologia , Osteotomia/métodos , Amplitude de Movimento Articular/fisiologia , Adulto , Idoso , Feminino , Seguimentos , Hallux Rigidus/fisiopatologia , Hallux Valgus/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
6.
Int Orthop ; 39(12): 2341-6, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26130277

RESUMO

PURPOSE: Unicompartmental knee arthroplasty (UKA) presents low morbidity and complication risk and provides excellent outcomes and fast recovery. Despite these facts, knee-replacement registries have shown high failure rates for UKA, especially when compared with traditional TKA. The purpose of this study was therefore to report outcomes, complications, and ten year survivorship rate of medial ZUK unicompartmental knee prosthesis. METHODS: We retrospectively analysed 136 medial UKAs in 124 patients, with a maximum follow-up of ten years. Patients were assessed through the International Knee Society (IKS) scores and range of motion (ROM). A complete X-ray study was performed in all patients. Limb alignment was assessed by measuring the femorotibial mechanical alignment. At surgery, bone resections were performed according to proximal tibial epiphyseal axis. RESULTS: Mean IKS knee score improved from 45.7 (range 35-63) points preoperatively to 87.2 (range 71-100) points at the latest follow-up. Mean IKS function score improved from 50.9 (range 40-70) points to 89.1 (range 75-100) points (p < 0.05). Mean ROM increased from 106.1° (range 98-123°) to 128.6° (range 116-139°) (p < 0.01). Four cases (2.9 %) were revised due to failure for any cause, so that survivorship was 97.1 % at the latest follow-up. CONCLUSIONS: This study demonstrates excellent outcomes and survivorship for the ZUK unicompartmental knee prosthesis. Based on our findings, we believe that the ZUK prosthesis offers an effective and durable solution for treating medial degeneration of the knee. Level of Evidence IV - Retrospective case series study.


Assuntos
Artroplastia do Joelho , Osteoartrite do Joelho/cirurgia , Sistema de Registros , Tíbia/cirurgia , Idoso , Idoso de 80 Anos ou mais , Artroplastia do Joelho/efeitos adversos , Feminino , Seguimentos , Humanos , Articulação do Joelho/cirurgia , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Falha de Prótese , Amplitude de Movimento Articular , Estudos Retrospectivos , Resultado do Tratamento
7.
Res Sq ; 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38826398

RESUMO

Lenia, a cellular automata framework used in artificial life, provides a natural setting to implement mathematical models of cancer incorporating features such as morphogenesis, homeostasis, motility, reproduction, growth, stimuli response, evolvability, and adaptation. Historically, agent-based models of cancer progression have been constructed with rules that govern birth, death and migration, with attempts to map local rules to emergent global growth dynamics. In contrast, Lenia provides a flexible framework for considering a spectrum of local (cell-scale) to global (tumor-scale) dynamics by defining an interaction kernel governing density-dependent growth dynamics. Lenia can recapitulate a range of cancer model classifications including local or global, deterministic or stochastic, non-spatial or spatial, single or multi-population, and off or on-lattice. Lenia is subsequently used to develop data-informed models of 1) single-population growth dynamics, 2) multi-population cell-cell competition models, and 3) cell migration or chemotaxis. Mathematical modeling provides important mechanistic insights. First, short-range interaction kernels provide a mechanism for tumor cell survival under conditions with strong Allee effects. Next, we find that asymmetric interaction tumor-immune kernels lead to poor immune response. Finally, modeling recapitulates immune-ECM interactions where patterns of collagen formation provide immune protection, indicated by an emergent inverse relationship between disease stage and immune coverage.

8.
bioRxiv ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38370722

RESUMO

Direct observation of immune cell trafficking patterns and tumor-immune interactions is unlikely in human tumors with currently available technology, but computational simulations based on clinical data can provide insight to test hypotheses. It is hypothesized that patterns of collagen formation evolve as a mechanism of immune escape, but the exact nature of the interaction between immune cells and collagen is poorly understood. Spatial data quantifying the degree of collagen fiber alignment in squamous cell carcinomas indicates that late stage disease is associated with highly aligned fibers. Here, we introduce a computational modeling framework (called Lenia) to discriminate between two hypotheses: immune cell migration that moves 1) parallel or 2) perpendicular to collagen fiber orientation. The modeling recapitulates immune-ECM interactions where collagen patterns provide immune protection, leading to an emergent inverse relationship between disease stage and immune coverage. We also illustrate the capabilities of Lenia to model the evolution of tumor progression and immune predation. Lenia provides a flexible framework for considering a spectrum of local (cell-scale) to global (tumor-scale) dynamics by defining a kernel cell-cell interaction function that governs tumor growth dynamics under immune predation with immune cell migration. Mathematical modeling provides important mechanistic insights into cell interactions. Short-range interaction kernels provide a mechanism for tumor cell survival under conditions with strong Allee effects, while asymmetric tumor-immune interaction kernels lead to poor immune response. Thus, the length scale of tumor-immune interactions drives tumor growth and infiltration.

9.
Cancer Prev Res (Phila) ; 17(4): 169-176, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38286404

RESUMO

As oropharyngeal cancer (OPC) associated with human papillomavirus (HPV) increases in men, the need for a screening test to diagnose OPC early is crucial. This study agnostically identified differentially methylated CpG sites to identify additional biomarkers to improve screening for early OPC.DNA was extracted from oral gargles of 89 early cases and 108 frequency matched healthy controls, and processed for genome-wide methylation using the Illumina Infinium MethylationEPIC BeadChip. Selected sites were combined with our prior methylation data in the EPB41L3 gene (CpG sites 438, 427, and 425) and oral HPV16 and HPV18 status were considered as binary variables (positive/negative). Lasso regression identified CpG sites strongly associated with early OPC. ROC curves with AUC were generated. The panel was validated utilizing bootstrap resampling.Machine learning analyses identified 14 markers that are significantly associated with early OPC, including one EPB41L3 CpG site (438) and oral HPV16 status. A final model was trained on all available samples using the discovered panel and was able to predict early OPC compared with controls with an AUC of 0.970 on the training set. In the bootstrap validation sets, the average AUC was 0.935, indicating adequate internal validity.Our data suggest that this panel can detect OPC early, however external validation of this panel is needed. Further refinement of a panel of biomarkers to diagnose OPC earlier is urgently needed to prevent complex treatment of OPC and associated comorbidities, while reducing risk of recurrence. PREVENTION RELEVANCE: This study identified biomarkers using genome-wide methylation to create a panel capable of discerning early oropharyngeal cancer (OPC) from those without OPC. Such a biomarker panel would be an effective tool to detect OPC early and prevent complications of treatment associated with later diagnosis.


Assuntos
Neoplasias Orofaríngeas , Infecções por Papillomavirus , Masculino , Humanos , Papillomavirus Humano , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/diagnóstico , Neoplasias Orofaríngeas/diagnóstico , Neoplasias Orofaríngeas/genética , Biomarcadores Tumorais/genética , Papillomavirus Humano 16/genética , Metilação , Proteínas dos Microfilamentos
10.
Oral Oncol ; 154: 106866, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38820888

RESUMO

OBJECTIVES: IRX-2 is a multi-cytokine immune-activating agent with anti-tumor activity in non-metastatic head and neck squamous cell carcinoma (HNSCC). Here, we evaluated combined IRX-2 and durvalumab in patients with recurrent and/or metastatic HNSCC. MATERIALS AND METHODS: This was a phase Ib trial consisting of dose escalation and expansion. Primary endpoints were safety and biomarkers to assess the immune response in the tumor microenvironment including significant increases in PD-L1 expression and CD8 + tumor infiltrating lymphocytes (TIL) comparing pre- and on-treatment tumor biopsies. Secondary endpoints were objective response rates (ORR) and survival outcomes. RESULTS: Sixteen patients were evaluable for response, and nine patients were evaluable for biomarkers. Thirteen patients (68 %) had exposure to prior anti-PD-1 therapy. No dose-limiting or grade ≥ 3 treatment-related adverse events were observed. On-treatment biopsies showed significantly increased PD-L1 (p = 0.005), CD3+ (p = 0.020), CD4+ (p = 0.022), and CD8 + T cells (p = 0.017) compared to pre-treatment. Median overall survival and progression-free survival (PFS) were 6.18 months (95 % CI, 2.66-8.61) and 2.53 months (95 % CI, 1.81-4.04), respectively. One patient had an objective response (ORR, 5.3 %) with an ongoing PFS of > 25 months. Disease control rate was 42 %. The responder harbored an ARID1A variant of unknown significance (VUS) that was predicted to bind her HLA-I alleles with a higher affinity than the reference peptide. CONCLUSIONS: IRX-2 and durvalumab were safe and elicited the evidence of immune activation in the tumor microenvironment determined by increased PD-L1 expression and CD8+ TILs. CLINICAL TRIAL REGISTRATION NUMBER: NCT03381183.


Assuntos
Anticorpos Monoclonais , Neoplasias de Cabeça e Pescoço , Recidiva Local de Neoplasia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/administração & dosagem , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Idoso , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/patologia , Recidiva Local de Neoplasia/tratamento farmacológico , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Metástase Neoplásica , Linfócitos do Interstício Tumoral/imunologia , Antígeno B7-H1/metabolismo , Microambiente Tumoral , Citocinas
11.
JCI Insight ; 9(9)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38716730

RESUMO

Lung cancer is the leading cause of cancer-related deaths in the world, and non-small cell lung cancer (NSCLC) is the most common subset. We previously found that infiltration of tumor inflammatory monocytes (TIMs) into lung squamous carcinoma (LUSC) tumors is associated with increased metastases and poor survival. To further understand how TIMs promote metastases, we compared RNA-Seq profiles of TIMs from several LUSC metastatic models with inflammatory monocytes (IMs) of non-tumor-bearing controls. We identified Spon1 as upregulated in TIMs and found that Spon1 expression in LUSC tumors corresponded with poor survival and enrichment of collagen extracellular matrix signatures. We observed SPON1+ TIMs mediate their effects directly through LRP8 on NSCLC cells, which resulted in TGF-ß1 activation and robust production of fibrillar collagens. Using several orthogonal approaches, we demonstrated that SPON1+ TIMs were sufficient to promote NSCLC metastases. Additionally, we found that Spon1 loss in the host, or Lrp8 loss in cancer cells, resulted in a significant decrease of both high-density collagen matrices and metastases. Finally, we confirmed the relevance of the SPON1/LRP8/TGF-ß1 axis with collagen production and survival in patients with NSCLC. Taken together, our study describes how SPON1+ TIMs promote collagen remodeling and NSCLC metastases through an LRP8/TGF-ß1 signaling axis.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Monócitos , Transdução de Sinais , Animais , Humanos , Camundongos , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/secundário , Linhagem Celular Tumoral , Colágeno/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/genética , Proteínas Relacionadas a Receptor de LDL/metabolismo , Proteínas Relacionadas a Receptor de LDL/genética , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/genética , Monócitos/metabolismo , Monócitos/patologia , Metástase Neoplásica , Fator de Crescimento Transformador beta1/metabolismo
12.
J Natl Cancer Inst ; 116(1): 105-114, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-37725515

RESUMO

BACKGROUND: Poor oral health has been identified as a prognostic factor potentially affecting the survival of patients with head and neck squamous cell carcinoma. However, evidence to date supporting this association has emanated from studies based on single cohorts with small-to-modest sample sizes. METHODS: Pooled analysis of 2449 head and neck squamous cell carcinoma participants from 4 studies of the International Head and Neck Cancer Epidemiology Consortium included data on periodontal disease, tooth brushing frequency, mouthwash use, numbers of natural teeth, and dental visits over the 10 years prior to diagnosis. Multivariable generalized linear regression models were used and adjusted for age, sex, race, geographic region, tumor site, tumor-node-metastasis stage, treatment modality, education, and smoking to estimate risk ratios (RR) of associations between measures of oral health and overall survival. RESULTS: Remaining natural teeth (10-19 teeth: RR = 0.81, 95% confidence interval [CI] = 0.69 to 0.95; ≥20 teeth: RR = 0.88, 95% CI = 0.78 to 0.99) and frequent dental visits (>5 visits: RR = 0.77, 95% CI = 0.66 to 0.91) were associated with better overall survival. The inverse association with natural teeth was most pronounced among patients with hypopharyngeal and/or laryngeal, and not otherwise specified head and neck squamous cell carcinoma. The association with dental visits was most pronounced among patients with oropharyngeal head and neck squamous cell carcinoma. Patient-reported gingival bleeding, tooth brushing, and report of ever use of mouthwash were not associated with overall survival. CONCLUSIONS: Good oral health as defined by maintenance of the natural dentition and frequent dental visits appears to be associated with improved overall survival among head and neck squamous cell carcinoma patients.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/epidemiologia , Saúde Bucal , Antissépticos Bucais , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Neoplasias de Cabeça e Pescoço/epidemiologia
13.
EMBO J ; 28(18): 2733-47, 2009 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-19644446

RESUMO

The CREB regulated transcription co-activators (CRTCs) regulate many biological processes by integrating and converting environmental inputs into transcriptional responses. Although the mechanisms by which CRTCs sense cellular signals are characterized, little is known regarding how CRTCs contribute to the regulation of cAMP inducible genes. Here we show that these dynamic regulators, unlike other co-activators, independently direct either pre-mRNA splice-site selection or transcriptional activation depending on the cell type or promoter context. Moreover, in other scenarios, the CRTC co-activators coordinately regulate transcription and splicing. Mutational analyses showed that CRTCs possess distinct functional domains responsible for regulating either pre-mRNA splicing or transcriptional activation. Interestingly, the CRTC1-MAML2 oncoprotein lacks the splicing domain and is incapable of altering splice-site selection despite robustly activating transcription. The differential usage of these distinct domains allows CRTCs to selectively mediate multiple facets of gene regulation, indicating that co-activators are not solely restricted to coordinating alternative splicing with increase in transcriptional activity.


Assuntos
Processamento Alternativo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ativação Transcricional , Adenoviridae/genética , Animais , Linhagem Celular Tumoral , Análise Mutacional de DNA , Regulação da Expressão Gênica , Hepatócitos , Humanos , Modelos Biológicos , Splicing de RNA , RNA Mensageiro/metabolismo , Ratos , Transcrição Gênica
14.
Oncogene ; 42(35): 2593-2609, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37474617

RESUMO

The head and neck region is one of the anatomic sites commonly afflicted by cancer, with ~1.5 million new diagnoses reported worldwide in 2020 alone. Remarkable progress has been made in understanding the underlying disease mechanisms, personalizing care based on each tumor's individual molecular characteristics, and even therapeutically exploiting the inherent vulnerabilities of these neoplasms. In this regard, genetically engineered mouse models (GEMMs) have played an instrumental role. While progress in the development of GEMMs has been slower than in other major cancer types, several GEMMs are now available that recapitulate most of the heterogeneous characteristics of head and neck cancers such as the tumor microenvironment. Different approaches have been employed in GEMM development and implementation, though each can generally recapitulate only certain disease aspects. As a result, appropriate model selection is essential for addressing specific research questions. In this review, we present an overview of all currently available head and neck cancer GEMMs, encompassing models for head and neck squamous cell carcinoma, nasopharyngeal carcinoma, and salivary and thyroid gland carcinomas.


Assuntos
Neoplasias de Cabeça e Pescoço , Camundongos , Animais , Modelos Animais de Doenças , Neoplasias de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Microambiente Tumoral/genética
15.
Nucleic Acids Res ; 38(4): 1249-60, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19966273

RESUMO

HIV-1 gene expression requires both viral and cellular factors to control and coordinate transcription. While the viral factor Tat is known for its transcriptional transactivator properties, we present evidence for an unexpected function of Tat in viral splicing regulation. We used a series of HIV-1 reporter minigenes to demonstrate that Tat's role in splicing is dependent on the cellular co-transcriptional splicing activators Tat-SF1 and CA150. Surprisingly, we show that this Tat-mediated splicing function is independent from transcriptional activation. In the context of the full-length viral genome, this mechanism promotes an autoregulatory feedback that decreases expression of tat and favors expression of the env-specific mRNA. Our data demonstrate that Tat-mediated regulation of transcription and splicing can be uncoupled and suggest a mechanism for the involvement of specific transcriptional activators in splicing.


Assuntos
Processamento Alternativo , HIV-1/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Linhagem Celular , Regulação Viral da Expressão Gênica , Humanos , RNA Polimerase II/metabolismo , Sítios de Splice de RNA , Transativadores/metabolismo , Ativação Transcricional , Fatores de Elongação da Transcrição , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo , Produtos do Gene nef do Vírus da Imunodeficiência Humana/genética , Produtos do Gene rev do Vírus da Imunodeficiência Humana/genética
16.
Sci Rep ; 12(1): 14256, 2022 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-35995931

RESUMO

Lysyl hydroxylase 2 (LH2) is a member of LH family that catalyzes the hydroxylation of lysine (Lys) residues on collagen, and this particular isozyme has been implicated in various diseases. While its function as a telopeptidyl LH is generally accepted, several fundamental questions remain unanswered: 1. Does LH2 catalyze the hydroxylation of all telopeptidyl Lys residues of collagen? 2. Is LH2 involved in the helical Lys hydroxylation? 3. What are the functional consequences when LH2 is completely absent? To answer these questions, we generated LH2-null MC3T3 cells (LH2KO), and extensively characterized the type I collagen phenotypes in comparison with controls. Cross-link analysis demonstrated that the hydroxylysine-aldehyde (Hylald)-derived cross-links were completely absent from LH2KO collagen with concomitant increases in the Lysald-derived cross-links. Mass spectrometric analysis revealed that, in LH2KO type I collagen, telopeptidyl Lys hydroxylation was completely abolished at all sites while helical Lys hydroxylation was slightly diminished in a site-specific manner. Moreover, di-glycosylated Hyl was diminished at the expense of mono-glycosylated Hyl. LH2KO collagen was highly soluble and digestible, fibril diameters were diminished, and mineralization impaired when compared to controls. Together, these data underscore the critical role of LH2-catalyzed collagen modifications in collagen stability, organization and mineralization in MC3T3 cells.


Assuntos
Colágeno Tipo I , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase , Colágeno/metabolismo , Colágeno Tipo I/metabolismo , Hidroxilação , Lisina/metabolismo , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/genética , Pró-Colágeno-Lisina 2-Oxoglutarato 5-Dioxigenase/metabolismo , Processamento de Proteína Pós-Traducional
17.
Neoplasia ; 29: 100799, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35504112

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is the 6th most common cancer worldwide and incidence rates are continuing to rise globally. Patients often present with locally advanced disease and a staggering 50% chance of relapse following treatment. Aberrant activation of adaptive response signaling pathways, such as the cAMP/PKA pathway, induce an array of genes associated with known cancer pathways that promote tumorigenesis and drug resistance. We identified the cAMP Regulated Transcription Coactivator 2 (CRTC2) to be overexpressed and constitutively activated in HNSCCs and this confers poor prognosis. CRTCs are regulated through their subcellular localization and we show that CRTC2 is exclusively nuclear in HPV(+) HNSCC, thus constitutively active, due to non-canonical Mitogen-Activated Kinase Kinase 1 (MEKK1)-mediated activation via a MEKK1-p38 signaling axis. Loss-of-function and pharmacologic inhibition experiments decreased CRTC2/CREB transcriptional activity by reducing nuclear CRTC2 via nuclear import inhibition and/or by eviction of CRTC2 from the nucleus. This shift in localization was associated with decreased proliferation, migration, and invasion. Our results suggest that small molecules that inhibit nuclear CRTC2 and p38 activity may provide therapeutic benefit to patients with HPV(+) HNSCC.


Assuntos
Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Carcinogênese , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Neoplasias de Cabeça e Pescoço/genética , Humanos , Mitógenos , Recidiva Local de Neoplasia , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Fatores de Transcrição/genética
18.
Cancer Res Commun ; 2(9): 987-1004, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36148399

RESUMO

Over 70% of oropharyngeal head and neck squamous cell carcinoma (HNSC) cases in the United States are positive for human papillomavirus (HPV) yet biomarkers for stratifying oropharyngeal head and neck squamous cell carcinoma (HNSC) patient risk are limited. We used immunogenomics to identify differentially expressed genes in immune cells of HPV(+) and HPV(-) squamous carcinomas. Candidate genes were tested in clinical specimens using both quantitative RT-PCR and IHC and validated by IHC using the Carolina Head and Neck Cancer Study (CHANCE) tissue microarray of HNSC cases. We performed multiplex immunofluorescent staining to confirm expression within the immune cells of HPV(+) tumors, receiver operating characteristic (ROC) curve analyses, and assessed survival outcomes. The neuronal gene Synaptogyrin-3 (SYNGR3) is robustly expressed in immune cells of HPV(+) squamous cancers. Multiplex immunostaining and single cell RNA-seq analyses confirmed SYNGR3 expression in T cells, but also unexpectedly in B cells of HPV(+) tumors. ROC curve analyses revealed that combining SYNGR3 and p16 provides more sensitivity and specificity for HPV detection compared to p16 IHC alone. SYNGR3-high HNSC patients have significantly better prognosis with five-year OS and DSS rates of 60% and 71%, respectively. Moreover, combining p16 localization and SYNGR3 expression can further risk stratify HPV(+) patients such that high cytoplasmic, low nuclear p16 do significantly worse (Hazard Ratio, 8.6; P = 0.032) compared to patients with high cytoplasmic, high nuclear p16. SYNGR3 expression in T and B cells is associated with HPV status and enhanced survival outcomes of HNSC patients.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Infecções por Papillomavirus , Humanos , Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/diagnóstico , Neoplasias de Cabeça e Pescoço/diagnóstico , Papillomavirus Humano , Infecções por Papillomavirus/complicações , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Sinaptogirinas
19.
EBioMedicine ; 86: 104373, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36442320

RESUMO

BACKGROUND: There is significant interest in treatment de-escalation for human papillomavirus-associated (HPV+) oropharyngeal squamous cell carcinoma (OPSCC) patients given the generally favourable prognosis. However, 15-30% of patients recur after primary treatment, reflecting a need for improved risk-stratification tools. We sought to develop a molecular test to risk stratify HPV+ OPSCC patients. METHODS: We created an immune score (UWO3) associated with survival outcomes in six independent cohorts comprising 906 patients, including blinded retrospective and prospective external validations. Two aggressive radiation de-escalation cohorts were used to assess the ability of UWO3 to identify patients who recur. Multivariate Cox models were used to assess the associations between the UWO3 immune class and outcomes. FINDINGS: A three-gene immune score classified patients into three immune classes (immune rich, mixed, or immune desert) and was strongly associated with disease-free survival in six datasets, including large retrospective and prospective datasets. Pooled analysis demonstrated that the immune rich group had superior disease-free survival compared to the immune desert (HR = 9.0, 95% CI: 3.2-25.5, P = 3.6 × 10-5) and mixed (HR = 6.4, 95% CI: 2.2-18.7, P = 0.006) groups after adjusting for age, sex, smoking status, and AJCC8 clinical stage. Finally, UWO3 was able to identify patients from two small treatment de-escalation cohorts who remain disease-free after aggressive de-escalation to 30 Gy radiation. INTERPRETATION: With additional prospective validation, the UWO3 score could enable biomarker-driven clinical decision-making for patients with HPV+ OPSCC based on robust outcome prediction across six independent cohorts. Prospective de-escalation and intensification clinical trials are currently being planned. FUNDING: CIHR, European Union, and the NIH.


Assuntos
Neoplasias de Cabeça e Pescoço , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Humanos , Infecções por Papillomavirus/complicações , Estudos Retrospectivos , Recidiva Local de Neoplasia , Neoplasias Orofaríngeas/terapia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Prognóstico , Biomarcadores , Papillomavirus Humano , Papillomaviridae
20.
Cancers (Basel) ; 13(4)2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33546179

RESUMO

Adenoid cystic carcinoma (ACC) is a rare salivary gland tumor, displaying aggressive behavior with frequent recurrence and metastasis. Little information exists regarding the impact of clinicopathological parameters and adjuvant radiotherapy (aRT) on ACC disease specific (DSS) and overall survival (OS). We extracted demographic, treatment, and survival information of 1439 patients with major or minor intraoral salivary gland ACC from the Surveillance, Epidemiology, and End Results (SEER) database. The associations between tumor characteristics and aRT with OS and DSS were estimated using hazard ratios (HR) and 95% confidence intervals (CI). Submandibular gland ACCs had the worst prognosis (adjusted DSS HR = 1.48; 95% CI = 0.99-2.20, compared to parotid), and this difference was more pronounced among patients with advanced-stage tumors (adjusted DSS HR = 1.93; 95% CI = 1.13-3.30). aRT was associated with increased overall survival only among stage III submandibular ACC patients (HR = 0.64; 95% CI = 0.42-0.98) and had no benefit in any other group. In conclusion, submandibular gland ACC carries a worse prognosis than other gland subsites and may benefit from aRT. The different outcomes between submandibular gland and other major or minor gland ACCs warrant further mechanistic investigation.

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