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1.
Mol Ther ; 31(3): 647-656, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36415148

RESUMO

Despite recent advances in molecular therapeutics, lung cancer is still a leading cause of cancer deaths. Currently, limited targeted therapy options and acquired drug resistance present significant barriers in the treatment of patients with lung cancer. New strategies in drug development, including those that take advantage of the intracellular ubiquitin-proteasome system to induce targeted protein degradation, have the potential to advance the field of personalized medicine for patients with lung cancer. Specifically, small molecule proteolysis targeting chimeras (PROTACs), consisting of two ligands connected by a linker that bind to a target protein and an E3 ubiquitin ligase, have been developed against many cancer targets, providing promising opportunities for advanced lung cancer. In this review, we focus on the rationale for PROTAC therapy as a new targeted therapy and the current status of PROTAC development in lung cancer.


Assuntos
Neoplasias Pulmonares , Complexo de Endopeptidases do Proteassoma , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas/metabolismo , Proteólise , Ubiquitina-Proteína Ligases/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética
2.
Nucleic Acids Res ; 49(10): 5779-5797, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-34048572

RESUMO

Faithful genome integrity maintenance plays an essential role in cell survival. Here, we identify the RNA demethylase ALKBH5 as a key regulator that protects cells from DNA damage and apoptosis during reactive oxygen species (ROS)-induced stress. We find that ROS significantly induces global mRNA N6-methyladenosine (m6A) levels by modulating ALKBH5 post-translational modifications (PTMs), leading to the rapid and efficient induction of thousands of genes involved in a variety of biological processes including DNA damage repair. Mechanistically, ROS promotes ALKBH5 SUMOylation through activating ERK/JNK signaling, leading to inhibition of ALKBH5 m6A demethylase activity by blocking substrate accessibility. Moreover, ERK/JNK/ALKBH5-PTMs/m6A axis is activated by ROS in hematopoietic stem/progenitor cells (HSPCs) in vivo in mice, suggesting a physiological role of this molecular pathway in the maintenance of genome stability in HSPCs. Together, our study uncovers a molecular mechanism involving ALKBH5 PTMs and increased mRNA m6A levels that protect genomic integrity of cells in response to ROS.


Assuntos
Homólogo AlkB 5 da RNA Desmetilase/metabolismo , Dano ao DNA , Reparo do DNA , Espécies Reativas de Oxigênio/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Linhagem Celular Tumoral , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , Desmetilação/efeitos dos fármacos , Proteínas de Grupos de Complementação da Anemia de Fanconi/genética , Proteínas de Grupos de Complementação da Anemia de Fanconi/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Metilação/efeitos dos fármacos , Camundongos , Fosforilação , Processamento de Proteína Pós-Traducional , RNA Interferente Pequeno , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , RNA-Seq , Sumoilação/efeitos dos fármacos , Espectrometria de Massas em Tandem , Proteína Nuclear Ligada ao X/genética , Proteína Nuclear Ligada ao X/metabolismo
3.
Geriatr Nurs ; 44: 131-136, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35150949

RESUMO

OBJECTIVES: Assess well-being among older adults through secondary analysis measured during an annual survey in 2018, 2019, and 2020, to determine trends from before and during the COVID-19 pandemic. METHODS: Mailed surveys sent annually included measures related to various psychosocial factors. MAIN FINDINGS: Response rates were 29% in 2018, 25% in 2019, and 24% in 2020. Most respondents reported average or high resilience (89% 2018-2020), high purpose (64% in 2018 and 2019, 63% in 2020), moderate optimism (46% in 2019, 44% in 2020) and low stress (88% in 2019 and 2020). Reported loneliness increased 13% from 2018 to 2020. In 2020, only 45% reported high comfort with technology, decreasing with age (>75). PRINCIPAL CONCLUSION: Psychosocial well-being of respondents were doing well despite changes related to COVID-19. However, increased loneliness may negatively impact long-term health outcomes; thus, a focus on technology options to stay socially connected and access healthcare are needed.


Assuntos
COVID-19/psicologia , Solidão , Resiliência Psicológica , Idoso , Humanos , Solidão/psicologia , Pandemias , Inquéritos e Questionários
4.
FASEB J ; 34(4): 4970-4983, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32057145

RESUMO

Liver regeneration after injury requires fine-tune regulation of connective tissue growth factor (Ctgf). It also involves dynamic expression of hepatocyte nuclear factor (Hnf)4α, Yes-associated protein (Yap), and transforming growth factor (Tgf)-ß. The upstream inducers of Ctgf, such as Yap, etc, are well-known. However, the negative regulator of Ctgf remains unclear. Here, we investigated the Hnf4α regulation of Ctgf post-various types of liver injury. Both wild-type animals and animals contained siRNA-mediated Hnf4α knockdown and Cre-mediated Ctgf conditional deletion were used. We observed that Ctgf induction was associated with Hnf4α decline, nuclear Yap accumulation, and Tgf-ß upregulation during early stage of liver regeneration. The Ctgf promoter contained an Hnf4α binding sequence that overlapped with the cis-regulatory element for Yap and Tgf-ß. Ctgf loss attenuated inflammation, hepatocyte proliferation, and collagen synthesis, whereas Hnf4α knockdown enhanced Ctgf induction and liver fibrogenesis. These findings provided a new mechanism about fine-tuned regulation of Ctgf through Hnf4α antagonism of Yap and Tgf-ß activities to balance regenerative and fibrotic signals.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fator 4 Nuclear de Hepatócito/metabolismo , Hepatócitos/metabolismo , Regeneração Hepática , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células , Colágeno/genética , Colágeno/metabolismo , Fator de Crescimento do Tecido Conjuntivo/genética , Células HEK293 , Células Hep G2 , Fator 4 Nuclear de Hepatócito/genética , Hepatócitos/fisiologia , Humanos , Camundongos , Ligação Proteica , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima , Proteínas de Sinalização YAP
5.
Aging Ment Health ; 25(7): 1239-1245, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32363903

RESUMO

BACKGROUND: Studies consistently demonstrate that older adults who are lonely have higher rates of depression and increased mortality risk. Pet ownership may be a solution for loneliness; however, challenges related to pet ownership exist for older adults. Therefore, researchers and practitioners are examining the use of animatronic pets to reduce loneliness. OBJECTIVE: To determine the feasibility of an animatronic pet program, and whether ownership of animatronic pets would decrease loneliness and improve well-being among lonely older adults. METHODS: Eligible individuals were identified as lonely through a prior survey. Participants were provided with the choice of an animatronic pet and completed T1/T2/T3 surveys. RESULTS: Attrition was high; 168 (63%) participants completed T1/T2 surveys, and 125 (48%) also completed a T3 survey. Post survey data indicated that loneliness decreased, while mental well-being, resilience, and purpose in life improved. Frequent interactions with the pets were associated with greater improvement in mental well-being and optimism. CONCLUSIONS: Animatronic pets appear to provide benefits for the well-being of lonely older adults. Future studies should employ randomized controlled designs examining the impact of animatronic pets.


Assuntos
Solidão , Animais de Estimação , Idoso , Animais , Humanos , Saúde Mental , Propriedade , Inquéritos e Questionários
6.
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
7.
World J Surg ; 40(11): 2673-2680, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27283188

RESUMO

BACKGROUND: Recent national infection control efforts have been directed at reducing postsurgical infection rates, related morbidity, and cost. We sought to evaluate population-level rates of deep sternal wound infection (DSWI) after cardiac surgery, associated mortality, and resource use compared to patients undergoing cardiac surgery without postoperative DSWI relative to historical trends. METHODS: We analyzed the MarketScan ® Commercial Claims Databases from 2009 to 2013 to identify adult patients who developed DSWI after open cardiac surgery. Patients with and without DSWI were compared. The outcomes of interest included 30-day, 90-day, and 1-year in-hospital mortality. Utilization outcomes, including total hospital days and inpatient costs, were calculated in the time period from the index cardiac surgery through 90 days after DSWI diagnosis. RESULTS: In this cohort, 176,537 patients underwent one or more cardiac surgery procedures. DSWI occurred in 2835 (1.6 %) patients. One-year mortality for patients with DSWI was 10.7 versus 2.5 % (P < 0.001) in patients without DSWI. Mean hospital days in patients with DSWI were 33 versus 9 days for patients without DSWI (P < 0.001). Mean cost for patients with DSWI was greater than 2.5 times that of patients without DSWI ($211,478 vs $82,089, P < 0.001). CONCLUSIONS: Treatment of DSWI results in substantial morbidity, mortality, and excess cost for treating facilities. The rates of DSWI have not decreased dramatically over the last 10-20 years. Thus, more attention needs to be focused toward understanding treatment variation that exists in patients diagnosed with DSWI.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Recursos em Saúde/estatística & dados numéricos , Esterno/microbiologia , Esterno/cirurgia , Infecção da Ferida Cirúrgica/mortalidade , Idoso , Efeitos Psicossociais da Doença , Feminino , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Infecção da Ferida Cirúrgica/economia , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Estados Unidos/epidemiologia
8.
BMC Cancer ; 15: 803, 2015 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-26503699

RESUMO

BACKGROUND: Mucoepidermoid carcinoma (MEC) arises from multiple organs and accounts for the most common types of salivary gland malignancies. Currently, patients with unresectable and metastatic MEC have poor long-term clinical outcomes and no targeted therapies are available. The majority of MEC tumors contain a t(11;19) chromosomal translocation that fuses two genes, CRTC1 and MAML2, to generate the chimeric protein CRTC1-MAML2. CRTC1-MAML2 displays transforming activity in vitro and is required for human MEC cell growth and survival, partially due to its ability to constitutively activate CREB-mediated transcription. Consequently, CRTC1-MAML2 is implicated as a major etiologic molecular event and a therapeutic target for MEC. However, the molecular mechanisms underlying CRTC1-MAML2 oncogenic action in MEC have not yet been systematically analyzed. Elucidation of the CRTC1-MAML2-regulated transcriptional program and its underlying mechanisms will provide important insights into MEC pathogenesis that are essential for the development of targeted therapeutics. METHODS: Transcriptional profiling was performed on human MEC cells with the depletion of endogenous CRTC1-MAML2 fusion or its interacting partner CREB via shRNA-mediated gene knockdown. A subset of target genes was validated via real-time RT-PCR assays. CRTC1-MAML2-perturbed molecular pathways in MEC were identified through pathway analyses. Finally, comparative analysis of CRTC1-MAML2-regulated and CREB-regulated transcriptional profiles was carried out to assess the contribution of CREB in mediating CRTC1-MAML2-induced transcription. RESULTS: A total of 808 differentially expressed genes were identified in human MEC cells after CRTC1-MAML2 knockdown and a subset of known and novel fusion target genes was confirmed by real-time RT-PCR. Pathway Analysis revealed that CRTC1-MAML2-regulated genes were associated with network functions that are important for cell growth, proliferation, survival, migration, and metabolism. Comparison of CRTC1-MAML2-regulated and CREB-regulated transcriptional profiles revealed common and distinct genes regulated by CRTC1-MAML2 and CREB, respectively. CONCLUSION: This study identified a specific CRTC1-MAML2-induced transcriptional program in human MEC cells and demonstrated that CRTC1-MAML2 regulates gene expression in CREB-dependent and independent manners. Our data provide the molecular basis underlying CRTC1-MAML2 oncogenic functions and lay a foundation for further functional investigation of CRTC1-MAML2-induced signaling in MEC initiation and maintenance.


Assuntos
Carcinoma Mucoepidermoide/genética , Proteínas de Ligação a DNA/genética , Perfilação da Expressão Gênica/métodos , Proteínas Nucleares/genética , Proteínas de Fusão Oncogênica/genética , Fatores de Transcrição/genética , Carcinoma Mucoepidermoide/metabolismo , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/biossíntese , Células HEK293 , Humanos , Proteínas Nucleares/biossíntese , Proteínas de Fusão Oncogênica/biossíntese , Transativadores , Fatores de Transcrição/biossíntese
9.
J Biol Chem ; 288(9): 6238-47, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23349461

RESUMO

SFMBT1 belongs to the malignant brain tumor domain-containing chromatin reader family that recognizes repressive histone marks and represses transcription. The biological functions and molecular basis underlying SFMBT1-mediated transcriptional repression are poorly elucidated. Here, our proteomic analysis revealed that SFMBT1 is associated with multiple transcriptional corepressor complexes, including CtBP/LSD1/HDAC complexes, polycomb repressive complexes, and malignant brain tumor family proteins, that collectively contribute to SFMBT1 repressor activity. During myogenesis, Sfmbt1 represses myogenic differentiation of cultured and primary myoblasts. Mechanistically, Sfmbt1 interacts with MyoD and mediates epigenetic silencing of MyoD target genes via recruitment of its associated corepressors and subsequent induction of epigenetic modifications and chromatin compaction. Therefore, our study identified novel mechanisms accounting for SFMBT1-mediated transcription repression and revealed an essential role of Sfmbt1 in regulating MyoD-mediated transcriptional silencing that is required for the maintenance of undifferentiated states of myogenic progenitor cells.


Assuntos
Montagem e Desmontagem da Cromatina/fisiologia , Inativação Gênica/fisiologia , Desenvolvimento Muscular/fisiologia , Proteínas Repressoras/metabolismo , Transcrição Gênica/fisiologia , Linhagem Celular , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Humanos , Proteína MyoD/genética , Proteína MyoD/metabolismo , Proteômica/métodos , Proteínas Repressoras/genética
10.
J Biol Chem ; 288(38): 27680-27691, 2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-23928305

RESUMO

Chromatin readers decipher the functional readouts of histone modifications by recruiting specific effector complexes for subsequent epigenetic reprogramming. The LSD1 (also known as KDM1A) histone demethylase complex modifies chromatin and represses transcription in part by catalyzing demethylation of dimethylated histone H3 lysine 4 (H3K4me2), a mark for active transcription. However, none of its currently known subunits recognizes methylated histones. The Snai1 family transcription factors are central drivers of epithelial-to-mesenchymal transition (EMT) by which epithelial cells acquire enhanced invasiveness. Snai1-mediated transcriptional repression of epithelial genes depends on its recruitment of the LSD1 complex and ensuing demethylation of H3K4me2 at its target genes. Through biochemical purification, we identified the MBT domain-containing protein SFMBT1 as a novel component of the LSD1 complex associated with Snai1. Unlike other mammalian MBT domain proteins characterized to date that selectively recognize mono- and dimethylated lysines, SFMBT1 binds di- and trimethyl H3K4, both of which are enriched at active promoters. We show that SFMBT1 is essential for Snai1-dependent recruitment of LSD1 to chromatin, demethylation of H3K4me2, transcriptional repression of epithelial markers, and induction of EMT by TGFß. Carcinogenic metal nickel is a widespread environmental and occupational pollutant. Nickel alters gene expression and induces EMT. We demonstrate the nickel-initiated effects are dependent on LSD1-SFMBT1-mediated chromatin modification. Furthermore, in human cancer, expression of SFMBT1 is associated with mesenchymal markers and unfavorable prognosis. These results highlight a critical role of SFMBT1 in epigenetic regulation, EMT, and cancer.


Assuntos
Cromatina/metabolismo , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal , Histona Desmetilases/metabolismo , Histonas/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Proteínas Repressoras/metabolismo , Carcinógenos/farmacologia , Cromatina/genética , Cromatina/patologia , Células Epiteliais/patologia , Células HEK293 , Histona Desmetilases/genética , Histonas/genética , Humanos , Metilação , Proteínas de Neoplasias/genética , Neoplasias/genética , Neoplasias/patologia , Níquel/efeitos adversos , Níquel/farmacologia , Proteínas Repressoras/genética , Fatores de Transcrição da Família Snail , Oligoelementos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
11.
Stem Cells ; 31(4): 823-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23307608

RESUMO

Muscular dystrophies are a group of devastating diseases characterized by progressive muscle weakness and degeneration, with etiologies including muscle gene mutations and regenerative defects of muscle stem cells. Notch signaling is critical for skeletal myogenesis and has important roles in maintaining the muscle stem cell pool and preventing premature muscle differentiation. To investigate the functional impact of Notch signaling blockade in muscle stem cells, we developed a conditional knock-in mouse model in which endogenous Notch signaling is specifically blocked in muscle stem cell compartment. Mice with Notch signaling inhibition in muscle stem cells showed several muscular dystrophic features and impaired muscle regeneration. Analyses of satellite cells and isolated primary myoblasts revealed that Notch signaling blockade in muscle stem cells caused reduced activation and proliferation of satellite cells but enhanced differentiation of myoblasts. Our data thus indicate that Notch signaling controls processes that are critical to regeneration in muscular dystrophy, suggesting that Notch inhibitor therapies could have potential side effects on muscle functions.


Assuntos
Células Musculares/citologia , Células Musculares/metabolismo , Desenvolvimento Muscular/fisiologia , Distrofias Musculares/metabolismo , Receptores Notch/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Animais , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Camundongos , Camundongos Knockout , Desenvolvimento Muscular/genética , Distrofias Musculares/genética , Mioblastos/citologia , Mioblastos/metabolismo , Receptores Notch/genética , Células Satélites de Músculo Esquelético/citologia , Células Satélites de Músculo Esquelético/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
12.
Proc Natl Acad Sci U S A ; 108(37): 15231-6, 2011 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-21896759

RESUMO

Angiogenesis is meticulously controlled by a fine balance between positive and negative regulatory activities. Vascular endothelial growth factor (VEGF) is a predominant angiogenic factor and its dosage is precisely regulated during normal vascular formation. In cancer, VEGF is commonly overproduced, resulting in abnormal neovascularization. VEGF is induced in response to various stimuli including hypoxia; however, very little is known about the mechanisms that confine its induction to ensure proper angiogenesis. Chromatin insulation is a key transcription mechanism that prevents promiscuous gene activation by interfering with the action of enhancers. Here we show that the chromatin insulator-binding factor CTCF binds to the proximal promoter of VEGF. Consistent with the enhancer-blocking mode of chromatin insulators, CTCF has little effect on basal expression of VEGF but specifically affects its activation by enhancers. CTCF knockdown cells are sensitized for induction of VEGF and exhibit elevated proangiogenic potential. Cancer-derived CTCF missense mutants are mostly defective in blocking enhancers at the VEGF locus. Moreover, during mouse retinal development, depletion of CTCF causes excess angiogenesis. Therefore, CTCF-mediated chromatin insulation acts as a crucial safeguard against hyperactivation of angiogenesis.


Assuntos
Cromatina/metabolismo , Elementos Isolantes/genética , Neovascularização Patológica/genética , Proteínas Repressoras/metabolismo , Dedos de Zinco/genética , Animais , Fator de Ligação a CCCTC , Linhagem Celular , Elementos Facilitadores Genéticos/genética , Genes Reporter/genética , Humanos , Camundongos , Neoplasias/irrigação sanguínea , Neoplasias/patologia , Neovascularização Patológica/patologia , Regiões Promotoras Genéticas/genética , Ligação Proteica , Retina/crescimento & desenvolvimento , Retina/patologia , Transcrição Gênica , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
13.
Mol Biol Rep ; 40(1): 217-23, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23079703

RESUMO

The Six1 homeoprotein belongs to the Six (sine oculis) transcription factor family, the members of which are known to act as master regulators of development. Six1 is essential for promoting myogenesis during mammalian somitogenesis. Previous studies have shown that Six1 participates in later steps of myogenic differentiation by enhancing early activation of myogenin via binding to the Mef3 site of the myogenin promoter. In the present study, however, we show that overexpression of Six1 via retroviral infection suppresses the expression of myogenin and myosin in C2C12 myoblasts, consequently retarding myogenic differentiation without affecting cell proliferation or expression of Mef2 and Mef3. These findings further demonstrate the functional role of Six1 in myogenesis.


Assuntos
Diferenciação Celular , Proteínas de Homeodomínio/genética , Desenvolvimento Muscular/genética , Mioblastos/citologia , Mioblastos/metabolismo , Animais , Linhagem Celular , Proliferação de Células , Expressão Gênica , Miogenina/genética , Miogenina/metabolismo , Miosinas/genética , Miosinas/metabolismo
14.
ScientificWorldJournal ; 2013: 178708, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24453806

RESUMO

The Notch signaling is an evolutionarily conserved cell-cell communication pathway that plays critical roles in the proliferation, survival, apoptosis, and fate determination of mammalian cells. Retinal pigment epithelial (RPE) cells are responsible for supporting the function of the neural retina and maintaining vision. This study investigated the function of Notch signaling in RPE cells. We found that the members of the Notch signaling pathway components were differentially expressed in RPE cells. Furthermore, blockage of Notch signaling inhibited the migration and proliferation of RPE cells and reduced the expression levels of certain Notch signaling target genes, including HES1, MYC, HEY2, and SOX9. Our data reveal a critical role of Notch signaling in RPE cells, suggesting that targeting Notch signaling may provide a novel approach for the treatment of ophthalmic diseases related to RPE cells.


Assuntos
Movimento Celular , Proliferação de Células , Receptor Notch1/fisiologia , Epitélio Pigmentado da Retina/citologia , Transdução de Sinais , Apoptose , Linhagem Celular , Linhagem da Célula , Células HEK293 , Humanos , Lentivirus/metabolismo , Neurônios/metabolismo , Plasmídeos/metabolismo , RNA/metabolismo , Receptor Notch1/metabolismo , Retina/metabolismo , Visão Ocular
15.
Nat Genet ; 33(2): 208-13, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12539049

RESUMO

Truncation of Notch1 has been shown to cause a subtype of acute leukemia, and activation of Notch4 has been associated with mammary and salivary gland carcinomas of mice. Here we identify a new mechanism for disrupting Notch signaling in human tumorigenesis, characterized by altered function of a new ortholog of the Drosophila melanogaster Notch co-activator molecule Mastermind. We cloned the t(11;19) translocation that underlies the most common type of human malignant salivary gland tumor. This rearrangement fuses exon 1 from a novel gene of unknown function at 19p13, termed mucoepidermoid carcinoma translocated 1 (MECT1), with exons 2-5 of a novel member of the Mastermind-like gene family (MAML2) at 11q21 (ref. 3). Similar to D. melanogaster Mastermind and MAML1 (refs. 4,5), full-length MAML2 functioned as a CSL (CBF-1, suppressor of hairless and Lag-1)-dependent transcriptional co-activator for ligand-stimulated Notch. In contrast, MECT1-MAML2 activated transcription of the Notch target gene HES1 independently of both Notch ligand and CSL binding sites. MECT1-MAML2 induced foci formation in RK3E epithelial cells, confirming a biological effect for the fusion product. These data suggest a new mechanism to disrupt the function of a Notch co-activator in a common type of malignant salivary gland tumor.


Assuntos
Fusão Gênica Artificial , Carcinoma Mucoepidermoide/genética , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 19/genética , Proteínas de Membrana/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Translocação Genética , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos , Carcinoma Mucoepidermoide/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Regulação da Expressão Gênica , Rearranjo Gênico , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Hibridização in Situ Fluorescente , Peptídeos e Proteínas de Sinalização Intercelular , Proteína Jagged-2 , Cariotipagem , Ligantes , Luciferases/metabolismo , Proteínas de Membrana/genética , Dados de Sequência Molecular , Mutação , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Epiteliais e Glandulares/metabolismo , Regiões Promotoras Genéticas , Receptores Notch , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Ribonuclease Pancreático/metabolismo , Neoplasias das Glândulas Salivares/genética , Neoplasias das Glândulas Salivares/metabolismo , Transdução de Sinais , Transativadores , Fatores de Transcrição HES-1 , Fatores de Transcrição , Transcrição Gênica , Ativação Transcricional , Transfecção , Células Tumorais Cultivadas
16.
Oncogene ; 42(47): 3457-3490, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37864030

RESUMO

Evidence from physical sciences in oncology increasingly suggests that the interplay between the biophysical tumor microenvironment and genetic regulation has significant impact on tumor progression. Especially, tumor cells and the associated stromal cells not only alter their own cytoskeleton and physical properties but also remodel the microenvironment with anomalous physical properties. Together, these altered mechano-omics of tumor tissues and their constituents fundamentally shift the mechanotransduction paradigms in tumorous and stromal cells and activate oncogenic signaling within the neoplastic niche to facilitate tumor progression. However, current findings on tumor biophysics are limited, scattered, and often contradictory in multiple contexts. Systematic understanding of how biophysical cues influence tumor pathophysiology is still lacking. This review discusses recent different schools of findings in tumor biophysics that have arisen from multi-scale mechanobiology and the cutting-edge technologies. These findings range from the molecular and cellular to the whole tissue level and feature functional crosstalk between mechanotransduction and oncogenic signaling. We highlight the potential of these anomalous physical alterations as new therapeutic targets for cancer mechanomedicine. This framework reconciles opposing opinions in the field, proposes new directions for future cancer research, and conceptualizes novel mechanomedicine landscape to overcome the inherent shortcomings of conventional cancer diagnosis and therapies.


Assuntos
Mecanotransdução Celular , Neoplasias , Humanos , Neoplasias/genética , Neoplasias/patologia , Transdução de Sinais , Microambiente Tumoral , Biofísica
17.
Biodes Manuf ; 6(6): 646-660, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38993804

RESUMO

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been spreading globally and threatening public health. Advanced in vitro models that recapitulate the architecture and functioning of specific tissues and organs are in high demand for COVID-19-related pathology studies and drug screening. Three-dimensional (3D) in vitro cultures such as self-assembled and engineered organoid cultures surpass conventional two-dimensional (2D) cultures and animal models with respect to the increased cellular complexity, better human-relevant environment, and reduced cost, thus presenting as promising platforms for understanding viral pathogenesis and developing new therapeutics. This review highlights the recent advances in self-assembled and engineered organoid technologies that are used for COVID-19 studies. The challenges and future perspectives are also discussed.

18.
Oncologist ; 17(2): 220-32, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22291092

RESUMO

The role of Notch signaling in cervical cancer is seemingly controversial. To confirm the function of Notch signaling in this type of cancer, we established a stable Notch1-activated cervical cancer HeLa cell line. We found that Notch1 activation resulted in apoptosis, cell cycle arrest, and tumor suppression. At the molecular level, we found that a variety of genes associated with cyclic AMP, G protein-coupled receptor, and cancer signaling pathways contributed to Notch1-mediated tumor suppression. We observed that the expression of somatostatin (SST) was dramatically induced by Notch1 signaling activation, which was accompanied by enhanced expression of the cognate SST receptor subtype 1 (SSTR1) and SSTR2. Certain genes, such as tumor protein 63 (TP63, p63), were upregulated, whereas others, such as B-cell lymphoma 2 (BCL-2), Myc, Akt, and STAT3, were downregulated. Subsequently, knockdown of Notch1-induced SST reversed Notch1-induced decrease of BCL-2 and increase of p63, indicating that Notch1-induced tumor suppression may be partly through upregulating SST signaling. Our findings support a possible crosstalk between Notch signaling and SST signaling. Moreover, Notch-induced SSTR activation could enhance SSTR-targeted cancer chemotherapy. Valproic acid (VPA), a histone deacetylase inhibitor, suppressed cell growth and upregulated the expression of Notch1 and SSTR2. A combination therapy with VPA and the SSTR2-targeting cytotoxic conjugate CPT-SST strongly led to greater suppression, as compared to each alone. Our findings thus provide us with a promising clinical opportunity for enhanced cancer therapy using combinations of Notch1-activating agents and SSTR2-targeting agents.


Assuntos
Receptor Notch1/fisiologia , Receptores de Somatostatina/fisiologia , Transdução de Sinais/fisiologia , Somatostatina/fisiologia , Neoplasias do Colo do Útero/prevenção & controle , Animais , Pontos de Checagem do Ciclo Celular , Proliferação de Células , Colforsina/farmacologia , AMP Cíclico/metabolismo , Feminino , Células HeLa , Humanos , Camundongos , Receptores de Somatostatina/antagonistas & inibidores , Neoplasias do Colo do Útero/patologia
19.
Biochem Biophys Res Commun ; 422(3): 522-6, 2012 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-22627135

RESUMO

CDA-II (cell differentiation agent II), isolated from healthy human urine, is a DNA methyltransferase inhibitor. Previous studies indicated that CDA-II played important roles in the regulation of cell growth and certain differentiation processes. However, it has not been determined whether CDA-II affects skeletal myogenesis. In this study, we investigated effects of CDA-II treatment on skeletal muscle progenitor cell differentiation, migration and proliferation. We found that CDA-II blocked differentiation of murine myoblasts C2C12 in a dose-dependent manner. CDA-II repressed expression of muscle transcription factors, such as Myogenin and Mef2c, and structural proteins, such as myosin heavy chain (Myh3), light chain (Mylpf) and MCK. Moreover, CDA-II inhibited C1C12 cell migration and proliferation. Thus, our data provide the first evidence that CDA-II inhibits growth and differentiation of muscle progenitor cells, suggesting that the use of CDA-II might affect skeletal muscle functions.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Metilases de Modificação do DNA/antagonistas & inibidores , Desenvolvimento Muscular/efeitos dos fármacos , Mioblastos Esqueléticos/efeitos dos fármacos , Mioblastos/efeitos dos fármacos , Peptídeos/farmacologia , Fenilacetatos/farmacologia , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Fatores de Transcrição MEF2 , Camundongos , Desenvolvimento Muscular/genética , Mioblastos/citologia , Mioblastos/imunologia , Mioblastos Esqueléticos/citologia , Mioblastos Esqueléticos/enzimologia , Fatores de Regulação Miogênica/antagonistas & inibidores , Miogenina/antagonistas & inibidores , Cadeias Pesadas de Miosina/antagonistas & inibidores
20.
Cells ; 11(14)2022 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-35883651

RESUMO

Epithelial-mesenchymal transition (EMT) is implicated in tumor metastasis and therapeutic resistance. It remains a challenge to target cancer cells that have undergone EMT. The Snail family of key EMT-inducing transcription factors directly binds to and transcriptionally represses not only epithelial genes but also a myriad of additional genomic targets that may carry out significant biological functions. Therefore, we reasoned that EMT inherently causes various concomitant phenotypes, some of which may create targetable vulnerabilities for cancer treatment. In the present study, we found that Snail transcription factors bind to the promoters of multiple genes encoding subunits of the AMP-activated protein kinase (AMPK) complex, and expression of AMPK genes was markedly downregulated by EMT. Accordingly, high AMPK expression in tumors correlated with epithelial cell markers and low AMPK expression in tumors was strongly associated with adverse prognosis. AMPK is the principal sensor of cellular energy status. In response to energy stress, AMPK is activated and critically reprograms cellular metabolism to restore energy homeostasis and maintain cell survival. We showed that activation of AMPK by energy stress was severely impaired by EMT. Consequently, EMT cancer cells became hypersensitive to a variety of energy stress conditions and primarily underwent pyroptosis, a regulated form of necrotic cell death. Collectively, the study suggests that EMT impedes the activation of AMPK signaling induced by energy stress and sensitizes cancer cells to pyroptotic cell death under energy stress conditions. Therefore, while EMT promotes malignant progression, it concurrently induces collateral vulnerabilities that may be therapeutically exploited.


Assuntos
Transição Epitelial-Mesenquimal , Neoplasias , Piroptose , Proteínas Quinases Ativadas por AMP/metabolismo , Transição Epitelial-Mesenquimal/genética , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Fatores de Transcrição da Família Snail , Estresse Fisiológico
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