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1.
Int J Mol Sci ; 25(3)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38338924

RESUMO

Adenoid cystic carcinoma (ACC) is a rare neoplasm known for its indolent clinical course, risk of perineural invasion, and late onset of distant metastasis. Due to the scarcity of samples and the tumor's rarity, progress in developing effective treatments has been historically limited. To tackle this issue, a high-throughput screening of epigenetic drugs was conducted to identify compounds capable of disrupting the invasive properties of the tumor and its cancer stem cells (CSCs). ACC cells were screened for changes in tumor viability, chromatin decondensation, Snail inhibition along tumor migration, and disruption of cancer stem cells. Seven compounds showed potential clinical interest, and further validation showed that Scriptaid emerged as a promising candidate for treating ACC invasion. Scriptaid demonstrated a favorable cellular toxicity index, effectively inhibited Snail expression, induced hyperacetylation of histone, reduced cell migration, and effectively disrupted tumorspheres. Additionally, LMK235 displayed encouraging results in four out of five validation assays, further highlighting its potential in combating tumor invasion in ACC. By targeting the invasive properties of the tumor and CSCs, Scriptaid and LMK235 hold promise as potential treatments for ACC, with the potential to improve patient outcomes and pave the way for further research in this critical area.


Assuntos
Carcinoma Adenoide Cístico , Hidroxilaminas , Quinolinas , Neoplasias das Glândulas Salivares , Humanos , Carcinoma Adenoide Cístico/tratamento farmacológico , Carcinoma Adenoide Cístico/genética , Carcinoma Adenoide Cístico/metabolismo , Histonas/metabolismo , Neoplasias das Glândulas Salivares/patologia , Linhagem Celular Tumoral , Epigênese Genética , Invasividade Neoplásica
2.
J Oral Pathol Med ; 52(4): 339-341, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36694271

RESUMO

BACKGROUD: The United States is facing a dramatic shortage of clinician-scientists within the domains of medicine and dentistry. POINT OF VIEW: In this perspective article, we stressed the problem involving the continuous shortage of specialized professionals capable of addressing complex basic sciences questions, while maintaining clinical relevance. Here we present a different perspective regarding the early engagement of young students to clinical sciences by teaming up with high schools across the United States, and to energize the debate on our current shortage of clinician-scientists.


Assuntos
Pesquisa Biomédica , Humanos , Estados Unidos , Adolescente , Poder Psicológico
3.
J Oral Pathol Med ; 51(6): 553-562, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34661317

RESUMO

AIM: To evaluate the potential use of Cephaeline as a therapeutic strategy to manage mucoepidermoid carcinomas (MEC) of the salivary glands. MATERIAL AND METHODS: UM-HMC-1, UM-HMC-2, and UM-HMC-3A MEC cell lines were used to establish the effects of Cephaeline over tumor viability determined by MTT assay. In vitro wound healing scratch assays were performed to address cellular migration while immunofluorescence staining for histone H3 lysine 9 (H3k9ac) was used to identify the acetylation status of tumor cells upon Cephaeline administration. The presence of cancer stem cells was evaluated by the identification of ALDH enzymatic activity by flow cytometry and through functional assays using in vitro tumorsphere formation. RESULTS: A single administration of Cephaeline resulted in reduced viability of MEC cells along with the halt on tumor growth and cellular migration potential. Administration of Cephaeline resulted in chromatin histone acetylation as judged by the increased levels of H3K9ac and disruption of tumorspheres formation. Interestingly, ALDH levels were increased in UM-HMC-1 and UM-HMC-3A cell lines, while UM-HMC-2 showed a reduced enzymatic activity. CONCLUSION: Cephaeline has shown anti-cancer properties in all MEC cell lines tested by regulating tumor cells' viability, migration, proliferation, and disrupting the ability of cancer cells to generate tumorspheres.


Assuntos
Carcinoma Mucoepidermoide , Acetilação/efeitos dos fármacos , Carcinoma Mucoepidermoide/metabolismo , Linhagem Celular Tumoral , Emetina/análogos & derivados , Emetina/farmacologia , Histonas/metabolismo , Humanos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia
4.
Int J Mol Sci ; 23(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35628190

RESUMO

Parathyroid tumors are very prevalent conditions among endocrine tumors, being the second most common behind thyroid tumors. Secondary hyperplasia can occur beyond benign and malignant neoplasia in parathyroid glands. Adenomas are the leading cause of hyperparathyroidism, while carcinomas represent less than 1% of the cases. Tumor suppressor gene mutations such as MEN1 and CDC73 were demonstrated to be involved in tumor development in both familiar and sporadic types; however, the epigenetic features of the parathyroid tumors are still a little-explored subject. We present a review of epigenetic mechanisms related to parathyroid tumors, emphasizing advances in histone modification and its perspective of becoming a promising area in parathyroid tumor research.


Assuntos
Hiperparatireoidismo , Neoplasias das Paratireoides , Epigênese Genética , Epigenômica , Código das Histonas/genética , Humanos , Hiperparatireoidismo/genética , Neoplasias das Paratireoides/genética
5.
Int J Mol Sci ; 23(10)2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35628446

RESUMO

The human body is endowed with an extraordinary ability to maintain different oxygen levels in various tissues and organs. The maintenance of physiological levels of oxygen is known as physoxia. The development of hypoxic conditions plays an important role in the biology of several pathologies, including cancer. In vitro studies using normal and neoplastic cells require that culture conditions be carried out under appropriate oxygen levels, either physoxic or hypoxic conditions. Such requirements are difficult to widely implement in laboratory practice, mainly due to the high costs of specialized equipment. In this work, we present and characterize a cost-effective method to culture cells under a range of oxygen levels using deoxidizing pouches. Our results show that physoxic and hypoxic levels using deoxidizing absorbers can be achieved either by implementing a gradual change in oxygen levels or by a regimen of acute depletion of oxygen. This approach triggers the activation of an epithelial-mesenchymal transition in cancer cells while stimulating the expression of HIF-1α. Culturing cancer cells with deoxidizing agent pouches revealed PI3K oncogenic pathway exacerbations compared to tumor cells growing under atmospheric levels of oxygen. Similar to the PI3K signaling disturbance, we also observed augmented oxidative stress and superoxide levels and increased cell cycle arrest. Most interestingly, the culture of cancer cells under hypoxia resulted in the accumulation of cancer stem cells in a time-dependent manner. Overall, we present an attractive, cost-effective method of culturing cells under appropriate physoxic or hypoxic conditions that is easily implementable in any wet laboratory equipped with cell culture tools.


Assuntos
Neoplasias , Oxigênio , Análise Custo-Benefício , Humanos , Hipóxia/metabolismo , Oxigênio/análise , Fosfatidilinositol 3-Quinases/metabolismo
6.
J Transl Med ; 18(1): 138, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-32216808

RESUMO

BACKGROUND: The skin is the largest organ of the human body. Upon injury, the skin triggers a sequence of signaling pathways that induce epithelial proliferation, migration, and ultimately, the re-establishment of the epithelial barrier. Our study explores the unknown epigenetic regulations of wound healing from a histone perspective. Posttranslational modifications of histones enhance chromatin accessibility and modify gene transcription. METHODS: Full-thickness wounds were made in the dorsal skin of twenty-four C57/B6 mice (C57BL/6J), followed by the use of ring-shaped silicone splints to prevent wound contraction. Tissue samples were collected at three time points (post-operatory day 1, 4, and 9), and processed for histology. Immunofluorescence was performed in all-time points using markers for histone H4 acetylation at lysines K5, K8, K12, and K16. RESULTS: We found well-defined histone modifications associated with the stages of healing. Most exciting, we showed that the epidermis located at a distance from the wound demonstrated changes in histone acetylation, particularly the deacetylation of histone H4K5, H4K8, and H4K16, and hyperacetylation of H4K12. The epidermis adjacent to the wound revealed the deacetylation of H4K5 and H4K8 and hyperacetylation of H4K12. Conversely, the migratory epithelium (epithelial tongue) displayed significant acetylation of H4K5 and H4K12. The H4K5 and H4K8 were decreased in the newly formed epidermis, which continued to display high levels of H4K12 and H4K16. CONCLUSIONS: This study profiles the changes in histone H4 acetylation in response to injury. In addition to the epigenetic changes found in the healing tissue, these changes also took place in tissues adjacent and distant to the wound. Furthermore, not only deacetylation but also hyperacetylation occurred during tissue repair and regeneration.


Assuntos
Epigênese Genética , Histonas , Acetilação , Animais , Histonas/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Cicatrização/genética
7.
FASEB J ; 33(12): 13435-13449, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31560860

RESUMO

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide and is characterized by a fast-paced growth. Like other solid tumors, the HNSCC growth rate results in the development of hypoxic regions identified by the expression of hypoxia-inducible factor 1α (HIF-1α). Interestingly, clinical data have shown that pharmacological induction of intratumoral hypoxia caused an unexpected rise in tumor metastasis and the accumulation of cancer stem cells (CSCs). However, little is known on the molecular circuitries involved in the presence of intratumoral hypoxia and the augmented population of CSCs. Here we explore the impact of hypoxia on the behavior of HNSCC and define that the controlling function of phosphatase and tensin homolog (PTEN) over HIF-1α expression and CSC accumulation are de-regulated during hypoxic events. Our findings indicate that hypoxic niches are poised to accumulate CSCs in a molecular process driven by the loss of PTEN activity. Furthermore, our data suggest that targeted therapies aiming at the PTEN/PI3K signaling may constitute an effective strategy to counteract the development of intratumoral hypoxia and the accumulation of CSCs.-Nascimento-Filho, C. H. V., Webber, L. P., Borgato, G. B., Goloni-Bertollo, E. M., Squarize, C. H., Castilho, R. M. Hypoxic niches are endowed with a protumorigenic mechanism that supersedes the protective function of PTEN.


Assuntos
Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/fisiopatologia , Células-Tronco Neoplásicas/patologia , PTEN Fosfo-Hidrolase/metabolismo , Animais , Apoptose , Movimento Celular , Proliferação de Células , Feminino , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Camundongos , Camundongos Nus , Invasividade Neoplásica , Células-Tronco Neoplásicas/metabolismo , PTEN Fosfo-Hidrolase/genética , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Oral Pathol Med ; 49(8): 771-779, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32450006

RESUMO

INTRODUCTION: Alterations of the epigenome may influence cancer initiation and progression. At the cellular level, histones are key regulators of chromatin accessibility and gene transcription; thus, the inhibition of histone deacetylase enzymes (HDACs) constitutes an attractive target for therapy. In this study, we investigated the effects of the HDAC inhibitor entinostat on oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: We tested the effects of entinostat on OSCC cell lines. Cell viability and growth were analyzed using MTT assay. Cell cycle analysis, cell apoptosis, cancer stem cell (CSC) content, and the concentration of reactive oxygen species (ROS) in OSCC tumor cells were assessed using flow cytometry. The expression of histones and cell cycle regulatory proteins was examined by Western blot. RESULTS: The administration of entinostat resulted in reduced proliferation of OSCC cells, followed by cell cycle arrest at the G0/G1 phase, as well as substantial tumor apoptosis. We found an increase in ROS production and significant reductions in CSCs. We also found that entinostat caused increased acetylation histone H3 and histone H4, and changes in the expression of cell cycle-associated proteins such as p21. CONCLUSION: This study indicates that entinostat is a potential novel therapeutic agent for OSCC by halting tumor proliferation, inducing cytotoxicity and intracellular ROS, and attacking the CSCs.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Apoptose , Benzamidas , Carcinoma de Células Escamosas/tratamento farmacológico , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Neoplasias Bucais/tratamento farmacológico , Piridinas , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico
9.
Clin Oral Implants Res ; 31(3): 274-281, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31876318

RESUMO

OBJECTIVES: The mechanisms involved in the initiation and progression of peri-implantitis lesions are poorly understood. It was the aim to determine the content and activation status of macrophages present in human peri-implantitis lesions and compare the current findings with the macrophage polarization associated with periodontitis lesions. MATERIAL AND METHODS: A total of 14 patients were studied in this investigation. Seven were soft tissue biopsies from dental implants affected by peri-implantitis that required explantation. Seven biopsies were from chronic periodontal disease. Immunofluorescence stains were performed using biomarkers to identify macrophages (CD68+ ) undergoing M1 polarization (iNOS+ ) and M2 polarization (CD206+ ), along with Hoechst 33,342 to identify DNA content. All samples were stained and photographed, and double-positive cells for CD68 and iNOS or CD68 and CD206 were quantified. RESULTS: All peri-implantitis biopsies examined revealed a mixed population of macrophages undergoing M1 polarization and M2 polarization. Further analysis demonstrated the co-expression of iNOS and CD206, which indicates the presence of a heterogenic immune response on peri-implantitis lesions. Macrophage polarization in peri-implantitis lesions presents a distinct pattern than in periodontitis. We observed a significant increase in the population of M1 macrophages on peri-implantitis samples compared to periodontal disease samples. CONCLUSION: Our results demonstrate that peri-implantitis has higher numbers of macrophages displaying a distinct macrophage M1 polarization signature compared to periodontitis lesions. This pattern may explain, in part, the distinct nature of peri-implantitis progression vs. periodontitis in humans.


Assuntos
Periodontite Crônica , Implantes Dentários , Peri-Implantite , Dente , Humanos , Macrófagos
10.
Clin Exp Pharmacol Physiol ; 47(5): 857-866, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31943292

RESUMO

Asparaginase is fundamental to the treatment of haematological malignancies. However, little has been studied on the effects that asparaginase could exert on solid tumours. Thus, this study aimed to evaluate the effects of asparaginase on an oral carcinoma cell line. The cytotoxicity of asparaginase in SCC-9 (tongue squamous cell carcinoma) and HaCaT (human keratinocyte) cell lines was evaluated with MTT cell viability assay. The cells were treated with asparaginase at 0.04, 0.16, 0.63, 1.0, 1.5, 2.5, and 5.0 IU/mL. Dose-response curves and IC50 values were obtained and the Tumour Selectivity Index (TSI) was calculated. The effect of asparaginase on procaspase-3 and nuclear factor κB (NFκB) expression was evaluated with western blot because it was reported that the overexpression of NFκB has been shown to contribute to tumour cell survival, proliferation, and migration. Caspase 3/7 staining was performed to identify cell death using flow cytometry. Effective asparaginase concentrations were lower for SCC-9 cells when compared to HaCaT cells. The cytotoxicity results at 48 and 72 hours were significantly different for SCC-9 cells. The TSI indicated that asparaginase was selective for the tumour cells. A decrease in procaspase-3 and NFκB protein levels was observed in SCC-9 cells. Furthermore, asparaginase resulted in significant apoptosis after 48 and 72 hours. Based on these results, asparaginase was cytotoxic in a dose- and time-dependent manner, induces apoptosis, and reduces NFκB expression in oral cancer cells. These results encourage further studies on the effectiveness of this enzyme as a treatment for solid tumours, especially head and neck cancer.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Asparaginase/farmacologia , NF-kappa B/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Neoplasias da Língua/tratamento farmacológico , Caspase 3/metabolismo , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Regulação para Baixo , Células HaCaT , Humanos , Transdução de Sinais , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Fatores de Tempo , Neoplasias da Língua/metabolismo , Neoplasias da Língua/patologia
11.
Int J Mol Sci ; 21(3)2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32019183

RESUMO

The circadian rhythm regulates the physiology and behavior of living organisms in a time-dependent manner. Clock genes have distinct roles including the control over gene expression mediated by the transcriptional activators CLOCK and BMAL1, and the suppression of gene expression mediated by the transcriptional repressors PER1/2 and CRY1/2. The balance between gene expression and repression is key to the maintenance of tissue homeostasis that is disrupted in the event of an injury. In the skin, a compromised epithelial barrier triggers a cascade of events that culminate in the mobilization of epithelial cells and stem cells. Recruited epithelial cells migrate towards the wound and reestablish the protective epithelial layer of the skin. Although we have recently demonstrated the involvement of BMAL and the PI3K signaling in wound healing, the role of the circadian clock genes in tissue repair remains poorly understood. Here, we sought to understand the role of BMAL1 on skin healing in response to injury. We found that genetic depletion of BMAL1 resulted in delayed healing of the skin as compared to wild-type control mice. Furthermore, we found that loss of Bmal1 was associated with the accumulation of Reactive Oxygen Species Modulator 1 (ROMO1), a protein responsible for inducing the production of intracellular reactive oxygen species (ROS). The slow healing was associated with ROS and superoxide dismutase (SOD) production, and pharmacological inhibition of the oxidative stress signaling (ROS/SOD) led to cellular proliferation, upregulation of Sirtuin 1 (SIRT1), and rescued the skin healing phenotype of Bmal1-/- mice. Overall, our study points to BMAL1 as a key player in tissue regeneration and as a critical regulator of ROMO1 and oxidative stress in the skin.


Assuntos
Fatores de Transcrição ARNTL/fisiologia , Antioxidantes/farmacologia , Epiderme/fisiologia , Regulação da Expressão Gênica , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Cicatrização/efeitos dos fármacos , Animais , Ritmo Circadiano , Epiderme/efeitos dos fármacos , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Knockout , Proteínas Mitocondriais/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo
12.
J Clin Periodontol ; 46(8): 830-839, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31152604

RESUMO

AIM: To explore the M1/M2 status of macrophage polarization from healthy, gingivitis, and periodontitis patient samples. MATERIALS AND METHODS: Gingival biopsies were collected from 42 individuals (14 gingivitis, 18 periodontitis, and 10 healthy samples) receiving periodontal therapy. Histomorphology analysis was performed with haematoxylin and eosin staining. Immunofluorescence was performed using a combination of CD68 (macrophages), iNOS (M1), and CD206 (M2) in order to acquire changes in macrophage polarization at a single-cell resolution. Macrophages were quantified under microscopy using narrow wavelength filters to detect Alexa 488, Alexa 568, Alexa 633 fluorophores, and Hoechst 33342 to identify cellular DNA content. RESULTS: Gingivitis and periodontitis samples showed higher levels of macrophages compared with healthy samples. Unexpectedly, periodontitis samples displayed lower levels of macrophages dispersed in the stromal tissues compared with gingivitis samples; however, it remained higher than healthy tissues. The polarization of macrophages appears to be reduced in periodontitis and showed similar levels to those observed in healthy tissues. CONCLUSIONS: Our study found that gingivitis and periodontitis differ from each other by the levels of macrophage infiltrate, but not by changes in macrophage polarization.


Assuntos
Gengivite , Doenças Periodontais , Periodontite , Gengiva , Humanos , Macrófagos
13.
Clin Oral Implants Res ; 29(11): 1085-1100, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30280418

RESUMO

OBJECTIVES: The presence of titanium (Ti) particles around dental implants has been reported in the literature for decades. The prospective presence of Ti debris on soft tissues surrounding dental implants has not been systematically investigated and remains to be explored. Hence, this review aimed to evaluate the origin, presence, characteristics, and location of Ti particles in relation to dental implants. MATERIAL AND METHODS: Literature searches were conducted by two reviewers independently based on the PRISMA guidelines. The systematic review identified studies on Ti particles derived from dental implants. We evaluated several parameters, including anatomical location, and the suspected methods of Ti particles release. RESULTS: The search resulted in 141 articles, of which 26 were eligible and included in the systematic review of the literature. The investigations reported Ti and metal-like particles in the soft (i.e., epithelial cells, connective tissue, and inflammatory cells) and hard (bone crest and bone marrow) tissues around the dental implants. Shape and size of the particles varied. The current literature reported a size range from 100 nm to 54 µm identified by multiple particles identification methods. CONCLUSION: Ti particles surrounding peri-implant tissues are a common finding. Peri-implantitis sites presented a higher number of particles compared to healthy implants. The particles were mostly around the implants and inside epithelial cells, connective tissue, macrophages, and bone. Various mechanisms were described as causes of Ti release, including friction during implant insertion, corrosion of the implant surface, friction at the implant-abutment interface, implantoplasty, and several methods used for implant surface detoxification.

14.
Histopathology ; 71(2): 278-286, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28326594

RESUMO

AIMS: Epigenetics refers to changes in cell characteristics that occur independently of modifications to the DNA sequence. Oral carcinogenesis is influenced by modifications in epigenetic mechanisms, including changes in histones, which are proteins that support chromatin remodelling for the dynamic regulation of gene expression and silencing. The dysregulation of histone acetylation can lead to the uncontrolled activity of different genes, thereby triggering events associated with malignant transformation. The aim of this study was to analyse the expression of acetyl-histone H3 at lys9 (H3K9ac) in oral leucoplakia (OL) and oral squamous cell carcinoma (OSCC) in addition to its association with cell proliferation, epithelial-mesenchymal transition (EMT) and clinical-pathological findings. METHODS AND RESULTS: Samples of normal oral mucosa (NOM), OL and OSCC were submitted to immunohistochemical analysis using anti-H3K9ac, Ki67 and vimentin. Slides were submitted to quantitative analysis regarding the percentage of positive cells. OSCC presented less expression of H3K9ac in comparison to OL (P < 0.01), whereas Ki67 and vimentin levels increased from OL to OSCC (P < 0.001 and P = 0.03, respectively). OSCC patients with poor prognosis had less H3K9ac expression (P = 0.04). The Kaplan-Meier cumulative survival curves also revealed lower survival rates in patients with less H3K9ac expression (P < 0.01). CONCLUSIONS: The present findings suggest that changes in H3K9ac occur during the process of oral carcinogenesis along with an increase in cell proliferation and EMT. The results demonstrate that H3K9ac may be a useful novel prognostic marker for OSCC.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/patologia , Histonas/metabolismo , Neoplasias Bucais/patologia , Acetilação , Adulto , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Transição Epitelial-Mesenquimal/genética , Feminino , Humanos , Estimativa de Kaplan-Meier , Leucoplasia Oral/genética , Leucoplasia Oral/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Prognóstico
16.
Int J Mol Sci ; 18(7)2017 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-28704968

RESUMO

Head and neck squamous carcinoma (HNSCC) is the sixth most prevalent cancer and one of the most aggressive malignancies worldwide. Despite continuous efforts to identify molecular markers for early detection, and to develop efficient treatments, the overall survival and prognosis of HNSCC patients remain poor. Accumulated scientific evidences suggest that epigenetic alterations, including DNA methylation, histone covalent modifications, chromatin remodeling and non-coding RNAs, are frequently involved in oral carcinogenesis, tumor progression, and resistance to therapy. Epigenetic alterations occur in an unsystematic manner or as part of the aberrant transcriptional machinery, which promotes selective advantage to the tumor cells. Epigenetic modifications also contribute to cellular plasticity during tumor progression and to the formation of cancer stem cells (CSCs), a small subset of tumor cells with self-renewal ability. CSCs are involved in the development of intrinsic or acquired therapy resistance, and tumor recurrences or relapse. Therefore, the understanding and characterization of epigenetic modifications associated with head and neck carcinogenesis, and the prospective identification of epigenetic markers associated with CSCs, hold the promise for novel therapeutic strategies to fight tumors. In this review, we focus on the current knowledge on epigenetic modifications observed in HNSCC and emerging Epi-drugs capable of sensitizing HNSCC to therapy.


Assuntos
Metilação de DNA/genética , Histonas/metabolismo , Antineoplásicos/uso terapêutico , Metilação de DNA/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Epigênese Genética/genética , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Humanos , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/efeitos dos fármacos , RNA não Traduzido/genética
17.
J Oral Maxillofac Surg ; 73(9): 1733.e1-12, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25957874

RESUMO

The oral conditions of adult edentulous patients with ectodermal dysplasia (ED) often lead to decreased physical and psychological health, and the negative effects can become as extreme as social and psychological isolation. However, restoring oral function of adult edentulous patients with ED using zygomatic implants (ZIs) or conventional implants (CIs) remains challenging for dentists because of the severe atrophy of these patients' alveolar ridges. This report describes 2 cases of adult edentulous siblings with ED; they exhibited severe alveolar bone atrophy and were treated with ZIs and CIs as bases to augment the bone in their anterior jaws. For these patients, bone augmentation was completed with an autogenous fibular graft. Although there was mild evidence of bone graft resorption in the maxilla, the bone augmentation procedures were successful in the 2 patients. Effective osseointegration of the implants was obtained. After placement, the functional and esthetic results of the oral rehabilitation were acceptable. More importantly, restoration of the patients' oral function enhanced their self-confidence and self-esteem. Therefore, restoring oral function in adult patients with ED and edentulous jaws using ZIs and CIs as the bases for bone augmentation is an effective approach.


Assuntos
Processo Alveolar/patologia , Displasia Ectodérmica/patologia , Boca Edêntula/reabilitação , Irmãos , Adulto , Implantação Dentária Endóssea , Humanos , Adulto Jovem
18.
Genes (Basel) ; 15(6)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38927646

RESUMO

This review article critically examines the pivotal role of chromatin organization in gene regulation, cellular differentiation, disease progression and aging. It explores the dynamic between the euchromatin and heterochromatin, coded by a complex array of histone modifications that orchestrate essential cellular processes. We discuss the pathological impacts of chromatin state misregulation, particularly in cancer and accelerated aging conditions such as progeroid syndromes, and highlight the innovative role of epigenetic therapies and artificial intelligence (AI) in comprehending and harnessing the histone code toward personalized medicine. In the context of aging, this review explores the use of AI and advanced machine learning (ML) algorithms to parse vast biological datasets, leading to the development of predictive models for epigenetic modifications and providing a framework for understanding complex regulatory mechanisms, such as those governing cell identity genes. It supports innovative platforms like CEFCIG for high-accuracy predictions and tools like GridGO for tailored ChIP-Seq analysis, which are vital for deciphering the epigenetic landscape. The review also casts a vision on the prospects of AI and ML in oncology, particularly in the personalization of cancer therapy, including early diagnostics and treatment optimization for diseases like head and neck and colorectal cancers by harnessing computational methods, AI advancements and integrated clinical data for a transformative impact on healthcare outcomes.


Assuntos
Envelhecimento , Inteligência Artificial , Cromatina , Epigênese Genética , Neoplasias , Humanos , Neoplasias/genética , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Envelhecimento/genética , Cromatina/genética , Medicina de Precisão/métodos , Aprendizado de Máquina
19.
J Burn Care Res ; 45(2): 499-507, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-37998258

RESUMO

Burn injuries are observed throughout a wide range of ages, with over 1.1 million Americans suffering burns yearly, and half of these require hospitalization. Epigenetic modifications are fast-acting mechanisms that allow the human body to respond and adapt to environmental changes, including burn injuries. There is a lack of understanding of the epigenetic role during burn-induced tissue repair. Here, we characterize the histone modifications that follow burn injury, aiming at future pharmacological intervention using drugs capable of targeting epigenetic events. A clinically relevant porcine burn model was used to recapitulate the skin healing process after the burn. Isolated skin tissues at different time points were used to detect the acetylation levels of histones H3K27, H4K5, H4K8, and H4K12 as significant players of gene transcription using MetaXpress High-Content Imaging Analysis. We observed that the acetylation of histones is dynamically adjusted throughout healing, and its modifications are uniquely expressed according to the anatomical location and time of healing. We also observed that histone H4K5 is the most widely expressed during healing, followed by histone H3K27. We observed that histones expressed in intact skin tissue adjacent to the burn site could sense the burn injury by changing its histone acetylation pattern compared to control skin from uninjured and distant skin. Using a clinically relevant animal model, we have generated a comprehensive landscape of epigenetic modifications during burn healing. Our data will help us identify novel epi-drugs capable of manipulating histone modifications during healing to accelerate the healing process.


Assuntos
Queimaduras , Histonas , Humanos , Suínos , Animais , Temperatura Alta , Queimaduras/genética , Epigênese Genética , Cicatrização
20.
Am J Cancer Res ; 13(1): 143-160, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36777521

RESUMO

Adenoid cystic carcinoma (ACC) patients face a highly infiltrative and metastatic disease characterized by poor survival rates and suboptimal response to available therapies. We have previously shown that sensitization of ACC tumors to chemotherapy using histone deacetylase inhibitors (HDACi) constitutes a promising therapeutic strategy to manage tumor growth. Here, we used patient-derived xenografts (PDX) from ACC tumors to evaluate the effects of in vivo administration of the HDAC inhibitor Entinostat combined with Cisplatin over tumor growth. RNA from PDX tumor samples receiving the proposed therapy were analyzed using NanoString technology to identify molecular signatures capable of predicting ACC response to the therapy. We also used an RNAseq dataset from 68 ACC patients to validate the molecular signature identified by the NanoString platform. We found that the administration of Entinostat combined with Cisplatin resulted in a potent tumor growth inhibition (TGI) ranging from 38% to 106% of the original tumor mass. Enhanced response to therapy is consistent with the reactivation of tumor suppressor genes, including SFRP1, and the downregulation of oncogenes like FGF8 and CCR7. Nanostring data from PDX tumors identified a genetic signature capable of predicting tumor response to therapy. We further stratified 68 ACC patients containing RNAseq data accordingly to the activity levels of the identified genetic signature. We found that 23% of all patients exhibit a genetic signature consistent with a high ACC tumor response rate to Entinostat and Cisplatin. Our study provides compelling preclinical data supporting the deployment of a powerful systemic anticancer therapy crafted and explicitly tested for ACC tumors.

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