RESUMO
Objectives: The objectives of this retrospective study were to analyze telehealth utilization for two specialty care practices: oral medicine (OM) and oral and maxillofacial surgery (OMFS) during the first 2 years of the pandemic, its impact as a new treatment modality and on participating providers, as well as identify the type of patient visit that most readily adopted telehealth. Methods: Retrospective study of patients who sought specialty services, OM and OMFS, at an outpatient clinic in a university health system setting between March 1, 2019, and February 28, 2022. Source data were obtained from Epic, an electronic medical record application. Data were graphed using Tableau and Microsoft Excel software. Statistical analysis was performed utilizing chi-squared test and analysis of variance (ANOVA). Results: OMFS utilized telehealth 12% of the time, and OM 8% of the time. The majority (87%) of telehealth visits were for return patients (RPs). Compared with the first year of the pandemic, there was a decrease in the number of telehealth visits in the second year (p = 0.0001). As of August 2022, new patient (NP) telehealth encounters have largely returned to prepandemic levels (0-1.5%), whereas RP telehealth visits remained at an average level of 11.4% (9.4-12.4%). Surveyed providers consider telehealth as an effective complement to in-person care and will continue its use (4.2/5 Likert scale). Conclusions: Telehealth has become a viable pathway of care for OM and OMFS who previously did not utilize the remote platform to deliver healthcare. As a new treatment modality, telehealth is perceived as impactful in increasing access to specialty care by participating providers. NP visits are now almost completely in person, but telehealth continues for RPs. Ongoing demand for telehealth highlights urgency to develop appropriate standards and effective remote diagnostic/monitoring tools to maximize telehealth's capability to leverage finite health care resources and increase access to specialty care.
Assuntos
Cirurgia Bucal , Telemedicina , Humanos , Estudos Retrospectivos , Atenção à Saúde , PandemiasRESUMO
The aim of this study is to review the current status of cancer chemoprevention and its effectiveness in treatment of oral premalignant lesions and prevention of their progression to oral cancer. The challenges encountered in the different oral cancer chemoprevention clinical trials, including lack of surrogate endpoints, reversal of histologic premalignant changes as study endpoints, tobacco use, human papillomavirus, delivery system, adverse effects and risk of bias in clinical studies, are presented.
Assuntos
Anticarcinógenos/uso terapêutico , Neoplasias Bucais/prevenção & controle , Lesões Pré-Cancerosas/prevenção & controle , Carcinogênese/efeitos dos fármacos , Carotenoides/uso terapêutico , Catequina/análogos & derivados , Catequina/uso terapêutico , Quimioprevenção , Humanos , Preparações de Plantas/uso terapêutico , Inibidor da Tripsina de Soja de Bowman-Birk/uso terapêutico , Inibidores da Tripsina/uso terapêuticoRESUMO
BACKGROUND: Tongue squamous cell carcinoma (TSCC) represents one of the major subsets of head and neck cancer, which is characterized by unfavorable prognosis, frequent lymph node metastasis, and high mortality rate. The molecular events regulating tongue tumorigenesis remain elusive. In this study, we aimed to identify and evaluate immune-related long non-coding RNAs (lncRNAs) as prognostic biomarkers in TSCC. METHODS: The lncRNA expression data for TSCC were obtained from The Cancer Genome Atlas (TCGA) and the immune-related genes were downloaded from the Immunology Database and Analysis Portal (ImmPort). Pearson correlation analysis was performed to identify immune-related lncRNAs. The TCGA TSCC patient cohort was randomly divided into training and testing cohorts. In the training cohort, univariate and multivariate Cox regression analyses were used to determining key immune-related lncRNAs, which were then validated through Cox regression analysis, principal component analysis (PCA), and receiver operating characteristic (ROC) analysis in the testing cohort. RESULTS: Six immune-related signature lncRNAs (MIR4713HG, AC104088.1, LINC00534, NAALADL2-AS2, AC083967.1, FNDC1-IT1) were found to have prognostic value in TSCC. Multivariate and univariate cox regression analyses showed that the risk score based on our six-lncRNA model, when compared to other clinicopathological factors (age, gender, stage, N, T), was an important indicator of survival rate. In addition, Kaplan-Meier survival analysis demonstrated significantly higher overall survival in the low-risk patient group than the high-risk patient group within both training and testing cohorts. The ROC analysis indicated that the AUCs for 5-year overall survival were 0.790, 0.691, and 0.721, respectively, for training, testing, and entire cohorts. Finally, PCA analysis demonstrated that the high-risk and low-risk patient groups presented significant deviation regarding their immune status. CONCLUSIONS: A prognostic model based on six immune-related signature lncRNAs was established. This six-lncRNA prognostic model has clinical significance and may be helpful in the development of personalized immunotherapy strategies.
Assuntos
Carcinoma de Células Escamosas , RNA Longo não Codificante , Neoplasias da Língua , Humanos , Carcinoma de Células Escamosas/genética , Neoplasias da Língua/genética , RNA Longo não Codificante/genética , Língua , Relevância Clínica , Proteínas de NeoplasiasAssuntos
Neoplasias Bucais , Alphapapillomavirus/fisiologia , Anticarcinógenos/uso terapêutico , Quimioprevenção , Detecção Precoce de Câncer , Humanos , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/prevenção & controle , Neoplasias Bucais/terapia , Terapia Neoadjuvante , Infecções por Papillomavirus/diagnóstico , Lesões Pré-Cancerosas/prevenção & controle , SobreviventesRESUMO
Aphthous ulcers are one of the most common oral diseases worldwide. Their clinical presentation is characterized by multiple, recurrent, small, round, or ovoid ulcers with circumscribed margins and erythematous haloes present in different sizes. Oral lesions similar to aphthous ulcers may be present in several systemic diseases. This article will summarize the differential diagnosis of aphthous ulceration, with emphasis on a practical guide for the management of recurrent aphthous ulceration, including topical and systemic therapy.
Assuntos
Estomatite Aftosa/diagnóstico , Estomatite Herpética/diagnóstico , Administração Tópica , Anti-Inflamatórios/administração & dosagem , Antivirais/administração & dosagem , Síndrome de Behçet/diagnóstico , Diagnóstico Diferencial , Humanos , Estomatite Aftosa/tratamento farmacológico , Estomatite Aftosa/patologia , Estomatite Herpética/tratamento farmacológico , Estomatite Herpética/patologiaRESUMO
Oral cancer accounts for 2 percent to 4 percent of all cancers diagnosed each year in the United States. In contrast to other cancers, the overall U.S. survival rate from oral cancer has not improved during the past 50 years, mostly due to late-stage diagnosis. Several noninvasive oral cancer detection techniques that emerged in the past decade will be discussed, with a brief overview of most common oral cancer chemopreventive agents.
Assuntos
Detecção Precoce de Câncer/métodos , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/prevenção & controle , Biomarcadores Tumorais/análise , Quimioprevenção/métodos , Corantes , Diagnóstico por Imagem/métodos , Educação em Odontologia , Humanos , Luminescência , Oncologia/educação , Neoplasias Bucais/mortalidade , Saliva/química , Taxa de Sobrevida , Estados UnidosRESUMO
Cerebral palsy (CP) is a set of nonprogressive neuromuscular disorders caused by defects in the developing fetal brain. The aim of this study is to investigate the prevalence and distribution of various dental conditions including dental caries and periodontitis among individuals with CP who receive care at the Rancho Los Amigos National Rehabilitation Center dental clinic. Medical records of 478 patients between the ages of 3 and 78 years were reviewed. Patients were divided into four age groups: 3-20, 21-35, 36-55, and 56 and above year old. Data related to their dental conditions including caries, periodontitis, and other oral diseases were assessed. Statistical analyses were conducted to evaluate the correlations between these oral diseases and age, gender, ethnicity as well as their living conditions (home or group home). The 36-55-year-old age group displayed significantly more caries and periodontitis than any other age groups. Individuals aged 3-20 years showed a significantly lower rate of periodontitis and caries. There was no significant association between gender and race with these outcome variables but there was a correlation between these variables and living conditions. Differences in oral health exist among people with CP from different age groups and living conditions. These findings suggest that there is a dire need for more oral hygiene training and education for the care givers. Dental schools should better prepare their graduates to meet the treatment demands of individuals with special healthcare needs.
Assuntos
Paralisia Cerebral/complicações , Paralisia Cerebral/reabilitação , Assistência Odontológica para Doentes Crônicos/organização & administração , Doenças da Boca/etiologia , Doenças da Boca/terapia , Saúde Bucal , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Boca/epidemiologia , Prevalência , Centros de Reabilitação , Estudos Retrospectivos , Estados UnidosRESUMO
Keloids are an excessive accumulation of extracellular matrix. Although numerous studies have shown elevated plasminogen activator inhibitor-1 (PAI-1) levels in keloid fibroblasts compared with those of normal skin. Their specific mechanisms involved in the differential expression of PAI-1 in these cell types. In this study, the upregulation of PAI-1 expression is demonstrated in keloid tissues and their derived dermal fibroblasts, attesting to the persistence, if any, of fundamental differences between in vivo and in vitro paradigms. We further examined the mechanisms involved in hypoxia-induced regulation of PAI-1 gene in dermal fibroblast derived from keloid lesions and associated clinically normal peripheral skins from the same patient. Primary cultures were exposed to an environmental hypoxia or desferroxamine. We found that the hypoxia-induced elevation of PAI-1 gene appears to be regulated at both transcriptional and post-transcriptional levels in keloid fibroblasts. Furthermore, our results showed a consistent elevation of HIF-1alpha protein level in keloid tissues compared with their normal peripheral skin controls, implying a potential role as a biomarker for local skin hypoxia. Treatment with antisense oligonucleotides against hypoxia-inducible factor 1alpha (HIF-1alpha) led to the downregulation of steady-state levels of PAI-1 mRNA under both normoxic and hypoxic conditions. Conceivably, our results suggest that HIF-1alpha may be a novel therapeutic target to modulate the scar fibrosis process.
Assuntos
Hipóxia Celular/fisiologia , Regulação da Expressão Gênica , Queloide/metabolismo , Inibidor 1 de Ativador de Plasminogênio/genética , Adulto , Células Cultivadas , Cicloeximida/farmacologia , Dactinomicina/farmacologia , Desferroxamina/farmacologia , Feminino , Fibroblastos/metabolismo , Meia-Vida , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia , Masculino , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologiaRESUMO
Keloids are characterized as an "over-exuberant" healing response resulting in a disproportionate extracellular matrix (ECM) accumulation and tissue fibrosis. In view of the integral role of inflammation and cytokines in the healing response, it is logical to assume that they may play a part in orchestrating the pathology of this "abnormal" healing process. Tumor necrosis factor-alpha (TNF-alpha) is a potent proinflammatory cytokine involved in activation of signaling events and transcriptional programs, such as NFkappaB. This study attempts to determine the difference in NFkappaB and its related genes expression and DNA binding activity between keloid and normal skin fibroblasts. Three keloid and normal skin tissues (NSk) and their derived fibroblasts were used to determine NFkappaB signaling pathway expression using specific cDNA microarrays, Western blot analysis and immunohistochemistry. Electrophoretic mobility gel shift assay (EMSA) was used to assess NFkappaB-binding activity, all assays were performed in the presence and absence of TNF-alpha. TNF-alpha up-regulated 15% of NFkappaB signal pathway related genes in keloid fibroblast compared to normal skin. At the protein level, keloid fibroblasts and tissues showed higher basal levels of TNF- receptor-associated factors-TRAF1, TRAF2-TNF-alpha, inhibitor of apoptosis (c-IAP-1), and NFkappaB, compared with NSk. Keloid fibroblasts showed a constitutive increase in NFkappaB-binding activity in comparison to NSk both with and without TNF-alpha treatment. NFkappaB and its targeted genes, especially the antiapoptotic genes, could play a role in keloid pathogenesis; targeting NFkappaB could help in developing therapeutic interventions for the treatment of keloid scarring.
Assuntos
Queloide/metabolismo , Queloide/fisiopatologia , NF-kappa B/metabolismo , Transdução de Sinais/fisiologia , Adolescente , Adulto , Western Blotting , Derme/citologia , Fibroblastos/fisiologia , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Halitosis (oral malodor, bad breath) is a condition affecting millions of Americans and is a major concern to the general public. In healthy individuals complaining of bad breath, the mouth is the main source of their oral malodor, more specifically the posterior dorsum of the tongue. Halitosis may also indicate an underlying medical condition that necessitates treatment. In a patient with oral malodor for whom an underlying systemic problem has been ruled out, improved oral hygiene, removal of tongue plaque, and, if necessary, antibacterial mouth rinses are advised.
Assuntos
Halitose , Halitose/etiologia , Halitose/terapia , HumanosRESUMO
White lesions are frequently found during the examination of the oral cavity. Although some benign physiologic entities may present as white lesions, systemic conditions, infections, and malignancies may also present as white oral lesions. An appreciation of the many clinical entities that white lesions may represent is necessary if a differential diagnosis of white lesions is to be elucidated. The appreciation of subtle clinical findings associated with white lesions of the oral cavity permits clinicians to better care for their patients.
Assuntos
Doenças da Boca/diagnóstico , Diagnóstico Diferencial , Humanos , Doenças da Boca/etiologia , Doenças da Boca/terapia , Neoplasias Bucais/diagnósticoRESUMO
Optical spectroscopy devices are being developed and tested for the screening and diagnosis of oral precancer and cancer lesions. This study reports a device that uses white light for detection of suspicious lesions and green-amber light at 545 nm that detect tissue vascularity on patients with several suspicious oral lesions. The clinical grading of vascularity was compared to the histological grading of the biopsied lesions using specific biomarkers. Such a device, in the hands of dentists and other health professionals, could greatly increase the number of oral cancerous lesions detected in early phase. The purpose of this study is to correlate the clinical grading of tissue vascularity in several oral suspicious lesions using the Identafi(®) system with the histological grading of the biopsied lesions using specific vascular markers. Twenty-one patients with various oral lesions were enrolled in the study. The lesions were visualized using Identafi(®) device with white light illumination, followed by visualization of tissue autofluorescence and tissue reflectance. Tissue biopsied was obtained from the all lesions and both histopathological and immunohistochemical studies using a vascular endothelial biomarker (CD34) were performed on these tissue samples. The clinical vascular grading using the green-amber light at 545 nm and the expression pattern and intensity of staining for CD34 in the different biopsies varied depending on lesions, grading ranged from 1 to 3. The increase in vascularity was observed in abnormal tissues when compared to normal mucosa, but this increase was not limited to carcinoma only as hyperkeratosis and other oral diseases, such as lichen planus, also showed increase in vascularity. Optical spectroscopy is a promising technology for the detection of oral mucosal abnormalities; however, further investigations with a larger population group is required to evaluate the usefulness of these devices in differentiating benign lesions from potentially malignant lesions.
Assuntos
Neoplasias Bucais/diagnóstico , Imagem Óptica/métodos , Lesões Pré-Cancerosas/diagnóstico , Espectrometria de Fluorescência/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34/análise , Biomarcadores Tumorais/análise , Biópsia/métodos , Carcinoma de Células Escamosas/irrigação sanguínea , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Eritroplasia/diagnóstico , Eritroplasia/patologia , Feminino , Humanos , Imuno-Histoquímica , Leucoplasia Oral/irrigação sanguínea , Leucoplasia Oral/diagnóstico , Leucoplasia Oral/patologia , Líquen Plano Bucal/diagnóstico , Líquen Plano Bucal/patologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/irrigação sanguínea , Neoplasias Bucais/patologia , Gradação de Tumores , Projetos Piloto , Lesões Pré-Cancerosas/irrigação sanguínea , Lesões Pré-Cancerosas/patologia , Adulto JovemRESUMO
Oral cancer has a tendency to be detected at late stage which is detrimental to the patients because of its high mortality and morbidity rates. Early detection of oral cancer is therefore important to reduce the burden of this devastating disease. In this review article, the most common oral precancerous lesions are discussed and the importance of early diagnosis is emphasized. In addition, the most common non-invasive oral cancer devices that can aid the general practitioners in early diagnosis are also discussed.
Assuntos
Detecção Precoce de Câncer/instrumentação , Neoplasias Bucais/diagnóstico , Lesões Pré-Cancerosas/diagnóstico , Transformação Celular Neoplásica/classificação , Corantes , Detecção Precoce de Câncer/métodos , Fluorescência , Humanos , Leucoplasia Oral/diagnóstico , LuminescênciaRESUMO
Oral premalignancy serves as an ideal model for study of chemopreventive agents. Although 13-cis-retinoic acid showed reversal of oral premalignancy, toxicity, and reversal of clinical response after cessation of therapy obviated its widespread use. A search for nontoxic agents with cancer preventive activity led us to evaluate Bowman Birk Inhibitor (BBI) formulated as BBI Concentrate (BBIC). We previously reported encouraging results in a phase IIa trial of BBIC in patients with oral leukoplakia with measurable clinical responses and favorable biomarker changes. On the basis of these results, we undertook a randomized, placebo controlled phase IIb trial with patients receiving BBIC or placebo for 6 months, with assessment of clinical response and change in lesion area as primary end point and an intent-to-treat analysis. One hundred and thirty two subjects were randomized; and 89 subjects completed six months on study drug or placebo. Both placebo and BBIC showed a statistically significant decrease in mean lesion area of 17.1% and 20.6%, respectively, and partial or greater clinical responses of 30% and 28% respectively. No significant difference between placebo and study drug arms was observed. Histologic review, review of photographs of lesions, and comparison of serum neu protein and oral mucosal cell protease activity also did not show significant differences between study arms. Probable reasons for these negative results were considered, are discussed, and include a placebo with non-BBIC clinical activity and reduced pharmacokinetic availability of the second batch of BBIC. This experience should be a strong cautionary note to those considering "Green" chemoprevention.
Assuntos
Leucoplasia Oral/tratamento farmacológico , Inibidor da Tripsina de Soja de Bowman-Birk/uso terapêutico , Inibidores da Tripsina/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Leucoplasia Oral/patologia , Masculino , Pessoa de Meia-Idade , PrognósticoRESUMO
Oral lichen planus (OLP) is a chronic inflammatory disease, which has been defined by the World Health Organization as a potential precancerous condition, representing a generalized state associated with a significantly increased risk of oral cancer. We would like to put forward a hypothesis that inflammatory mediators such as cytokines and chemokines released from infiltrating T lymphocytes induce fundamental changes of proteins in oral epithelial cells, leading to the progression of OLP to oral squamous cell carcinoma (OSCC). These altered proteins can act as the key risk factors associated with the local microenvironment and development of OSCC. Identification of these proteins would add to our understanding of the connection between chronic inflammation and OSCC.
Assuntos
Carcinoma de Células Escamosas/etiologia , Quimiocinas/metabolismo , Citocinas/metabolismo , Inflamação/imunologia , Líquen Plano Bucal/imunologia , Linfócitos T/imunologia , Células Epiteliais/metabolismo , Humanos , Inflamação/complicações , Inflamação/patologia , Líquen Plano Bucal/complicações , Líquen Plano Bucal/patologia , Proteínas/metabolismo , Fatores de Risco , Linfócitos T/metabolismoRESUMO
Keloids represent a prolonged inflammatory fibrotic state with areas that display distinctive histological features characterized by an abundant extracellular matrix stroma, a local infiltration of inflammatory cells including mast cells, and a milieu of enriched cytokines. Previous studies from our laboratory demonstrated an intrinsic higher level of HIF-1alpha and VEGF protein expression in keloid tissues compared with their adjacent unremarkable skins. To further investigate the mechanisms underlying the elevated expression of HIF-1alpha and VEGF in keloids, we exposed a co-culture of keloid fibroblasts and mast cells (HMC-1) to hypoxic conditions and studied the expression of HIF-1alpha and its target gene, VEGF. Our results showed that hypoxia-dependent HIF-1alpha protein accumulation and VEGF expression is augmented in keloid fibroblasts when co-cultured with HMC-1 cells under the condition where direct cell-cell contact is allowed. But such augmentation is not observed in the transwell co-culture system whereas fibroblasts and HMC-1 cells were separated by a porous membrane. Our results also indicated that the enhancement of hypoxia-mediated activation of ERK1/2 and Akt requires direct cell-cell interaction between mast cells and keloid fibroblasts, and activation of both ERK1/2 and Akt is involved in the hypoxia-dependent HIF-1alpha protein accumulation and VEGF expression in the co-culture system. These findings suggest that under hypoxic conditions mast cells may contribute, at least in part, to an elevated expression of HIF-1alpha and VEGF protein in keloids via direct cell-cell interaction with fibroblasts.
Assuntos
MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fibroblastos/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Queloide , Mastócitos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Comunicação Celular/fisiologia , Hipóxia Celular/fisiologia , Células Cultivadas , Técnicas de Cocultura , Fibroblastos/citologia , Humanos , Queloide/patologia , Mastócitos/citologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Keloid, a chronic fibro-proliferative disease, exhibits distinctive histological features characterized by an abundant extracellular matrix stroma, a local infiltration of inflammatory cells including mast cells (MCs), and a milieu of enriched cytokines. Previous studies have demonstrated that co-culture with MCs stimulate type I collagen synthesis in fibroblasts, but the signaling mechanisms remain largely unknown. In this study, we investigated the signaling pathways involved in MC-stimulated type I collagen synthesis and the effects of green tea extract (GTE) and its major catechin, (-)-epigallocatechin-3-gallate (EGCG), on collagen homeostasis in keloid fibroblasts. Our results showed that MCs significantly stimulated type I collagen expression in keloid fibroblasts, and the upregulation of type I collagen was significantly attenuated by blockade of phosphatidylinositol-3-kinase (PI-3K), mammalian target of rapamycin (mTOR), and p38 MAPK signaling pathways, but not by blockade of ERK1/2 pathway. Furthermore, GTE and EGCG dramatically inhibited type I collagen production possibly by interfering with the PI-3K/Akt/mTOR signaling pathway. Our findings suggest that interaction between MCs and keloid fibroblasts may contribute to excessive collagen accumulation in keloids and imply a therapeutic potential of green tea for the intervention and prevention of keloids and other fibrotic diseases.
Assuntos
Camellia sinensis/química , Catequina/análogos & derivados , Colágeno Tipo I/metabolismo , Fibroblastos/metabolismo , Queloide/metabolismo , Mastócitos/fisiologia , Extratos Vegetais/farmacologia , Catequina/farmacologia , Células Cultivadas , Técnicas de Cocultura , Humanos , Queloide/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
One of the major impediments in keloid research is the lack of a keloid animal model that can mimic human keloid. This imposes investigative constraints on studying cellular interactions and biochemical processes that normally occur in vivo. Our main objective is to establish an in vitro model for maintaining long-term viable keloid dermal explants as a tool for investigating the pathogenesis of keloid scar formation. Explants of adult keloid scars were cultured in vitro by embedding them in enriched collagen gel matrix and maintaining them for up to 6 weeks, whereupon changes in tissue morphology and cellular differentiation were examined. The effects of medium enrichment, air versus liquid submersion, and different substrates on the explants were examined. Our results indicated that keloid explants embedded in a collagen gel matrix were morphologically better preserved than explants placed on a plastic substrate. Explants with epidermis at the air-liquid interface had better morphology than collagen-submerged explants, and there were no differences between serum-free and serum-supplemented explant cultures. Immunohistochemical and apoptotic analyses were performed to assess cellular viability and differentiation. In situ hybridization confirmed that keloid fibroblasts had sustained collagen type I gene expression throughout the 6 weeks in culture, thus validating the integrity of a long-term keloid culture system. In conclusion, the collagen-embedded skin explant system demonstrates that keloid tissues could be maintained for up to 6 weeks for long-term in vitro studies.
Assuntos
Queloide/imunologia , Queloide/patologia , Técnicas de Cultura de Órgãos , Diferenciação Celular , Colágeno/metabolismo , Colágeno Tipo I/análise , Colágeno Tipo I/genética , Humanos , Imuno-Histoquímica , Plásticos/metabolismo , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Pele/citologia , Pele/imunologia , Pele/patologiaRESUMO
Tissue microenvironment plays a critical role in tumour growth and invasion. This study established a novel 3-dimensional (3-D) cell invasion model for direct microscopic observation of oral cancer cell invasion into the underlying basement membrane and connective tissue stroma. A multilayer cell construct was developed using the OptiCell chamber, consisting of a lower layer of oral mucosa fibroblasts embedded in collagen gel and an overlaying upper layer of oral cancer cells. The two layers are separated by a basement membrane composed of reconstituted extracellular matrix. To verify the applicability of the cell invasion model, multilayer cell constructs of oral squamous cell carcinoma and oral mucosal fibroblasts were exposed to extrinsic urokinase-type plasminogen activator (uPA) or plasminogen activator inhibitor (PAI-1), which are known effectors of cell migration. In addition, the constructs were exposed to both normoxic and hypoxic culture conditions. Microscopic study showed that the presence of uPA enhanced cell invasion, while PAI-1 inhibited cell migration. Western blot and zymographic analysis demonstrated that hypoxia up-regulated uPA and matrix metalloproteinases (MMPs) expression and activity; conversely, PAI-1 level was down-regulated in response to hypoxic challenge as compared to normoxic condition. Our results indicated that the novel 3-D invasion model could serve as an excellent in vitro model to study cancer cell invasion and to test conditions or mediators of cellular migration.
Assuntos
Neoplasias Bucais/patologia , Western Blotting/métodos , Hipóxia Celular , Técnicas de Cocultura/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Fibroblastos/patologia , Humanos , Mucosa Bucal/patologia , Neoplasias Bucais/enzimologia , Invasividade Neoplásica , Inibidor 1 de Ativador de Plasminogênio/farmacologia , Ativador de Plasminogênio Tipo Uroquinase/farmacologiaRESUMO
Understanding the development and progression of oral cancer is critical in the quest for successful therapeutic intervention. The hypoxic microenvironment present in human oral tumor in vivo may actively influence tumor growth and neovascularization. This study correlates expression of both VEGF and HIF-1alpha in normal keratinocytes and oral cancer cell lines and determine whether hypoxia played a role in VEGF and HIF-1alpha regulation. Three human oral cancer cell lines and three normal keratinocytes were exposed to both normoxia and hypoxia culture conditions. Northern and Western blot analysis were used to assess VEGF and HIF-1alpha expression in the different culture conditions. ELISA assays were performed to measure VEGF production in the different cell lines tested. Hypoxia upregulated VEGF and HIF-1alpha expression on both normal and oral cancer cell lines, with a statistically significant difference between normal and oral cancer cell lines. Pattern of hypoxia-induced VEGF mRNA level tightly followed the HIF-1alpha mRNA expression in the cell lines tested. These results suggest that hypoxia regulates both VEGF and HIF-1alpha expression in head and neck carcinoma cell lines, thus establishing a biochemical pathway between tumor hypoxia and neoangiogenesis in these aggressive neoplasms.