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OBJECTIVES: To determine the relative frequency, demographic and pathologic profiles of patients diagnosed with cysts of the jaws. MATERIALS AND METHODS: Biopsy records of the participating institutions from 2000 to 2020 were reviewed for lesions diagnosed in the cyst category. Demographic data, the location of the cysts and pathologic diagnoses were collected. Data were analyzed by appropriate statistics using IBM SPSS software version 28.0. RESULTS: From 148,353 accessioned cases, 25,628 cases (17.28%) were diagnosed in the cyst category. Mean age of the patients ± SD = 42.62 ± 19.36 years. Paediatric patients (aged ≤ 16 years) accounted for 9.63%, while geriatric patients (aged ≥ 65) comprised 14.22% of all the patients. The male-to-female ratio was 1.27:1. The majority of the lesions were encountered in the mandible. The most prevalent cyst was radicular cyst followed by dentigerous cyst and odontogenic keratocyst. In the paediatric group, dentigerous cyst was the most prevalent, whereas in the geriatric group, radicular cyst was the most common. CONCLUSIONS: In general, the results of this study are in accordance with previous studies. This study provides an invaluable database for clinicians when formulating clinical differential diagnoses as well as for pathologists in rendering the final diagnosis.
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OBJECTIVE: To determine the prevalence of oral and maxillofacial lesions in a Thai pediatric population. MATERIAL AND METHOD: Oral biopsy records from pediatric patients between the ages of 0 and 15 years in the files ofFaculty of Dentistry, Mahidol University, and the files of Faculty of Dentistry, Khon Kaen University were reviewed. The patients were divided into three age groups, including 0 to 5, 6 to 10, and 11 to 15 years. Excluding the diagnosis of normal tissues, the oral and maxillofacial lesions were classified into nine categories. RESULTS: Of 13,050 biopsied oral and maxillofacial lesions, 1,389 cases (10.6%) came from pediatric patients. The largest number of lesions was odontogenic cysts and tumors, followed by inflammatory and reactive lesions, and salivary gland pathology The top ten most prevalent lesions contributed 73% of all oral biopsies. The most common lesion was dentigerous cyst, followed by mucocele and pyogenic granuloma. CONCLUSION: The vast majority of oral diseases in children were benign and related to either developmental or tissue reaction, while malignant lesions were found in a very small proportion of all oral biopsies.
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Quiste Dentígero/epidemiología , Enfermedades de la Boca/epidemiología , Neoplasias de la Boca/epidemiología , Mucocele/epidemiología , Adolescente , Biopsia , Niño , Preescolar , Quiste Dentígero/patología , Femenino , Humanos , Lactante , Masculino , Enfermedades de la Boca/patología , Neoplasias de la Boca/patología , Mucocele/patología , Prevalencia , Estudios Retrospectivos , Facultades de Odontología , Tailandia/epidemiologíaRESUMEN
OBJECTIVE: Very little is known about the role of trefoil factors (TFFs) in salivary gland tumors, and TFF immunoexpression has never been investigated in such tumors. The aim of this study was to evaluate TFF immunoexpression in benign and malignant salivary gland tumors. MATERIALS AND METHODS: Benign (n = 25) and malignant (n = 25) salivary gland tumor specimens were included in this study, using mucocele (n = 25) specimens as a control group. Immunohistochemical staining was performed to evaluate the expression of TFFs (TFF1, TFF2, and TFF3) by semiquantitative means. RESULTS: Expression of TFF1, TFF2, and TFF3 was significantly increased in benign (p = 0.001, p = 0.005, p < 0.001, respectively) and malignant (p < 0.001, p < 0.001, p < 0.001, respectively) groups as compared with the control group. Patterns of co-expression between TFF1/TFF2, TFF2/TFF3, and TFF1/TFF3 were different among the three groups. CONCLUSIONS: The present study provided new information showing that all TFFs were significantly increased in benign and malignant salivary gland tumors, and overexpression of TFFs could be associated with neoplastic transformation in salivary gland tissues. CLINICAL RELEVANCE: Overexpression of TFFs may be useful as biomarkers in terms of differential diagnosis between salivary gland tumors and other oral neoplasms for which clinical manifestations are indistinguishable.
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Péptidos/metabolismo , Neoplasias de las Glándulas Salivales/metabolismo , Adolescente , Adulto , Estudios de Casos y Controles , Humanos , Factor Trefoil-2 , Adulto JovenRESUMEN
Background: A pyogenic granuloma (PG) is a common benign vascular lesion found in the oral cavity. The gold standard treatment of this lesion, comprising surgical excision and the elimination of etiological factors, cannot avoid tooth loss in the case of an aggressive pyogenic granuloma. Because of the prominent properties of 980 nm and 635 nm diode lasers in photocoagulation and photobiomodulation, we applied these wavelengths in the treatment of a large pyogenic granuloma with alveolar bone loss. Case presentation: Our objective was to use a combination of interstitial-intralesional laser therapy, photocoagulation and laser-assisted new attachment procedure (LANAP) to preserve the teeth and periodontal tissue in a case of an aggressive pyogenic granuloma. Results: The patient was a 13-year-old Thai male with a pyogenic granuloma involving the interdental papilla and lingual gingiva of the lower left first and second molars. The teeth were also displaced by the lesion. After treatment with three sessions of photocoagulation, three sessions of interstitial-intralesional laser therapy and two sessions of LANAP, the lesion was completely resolved. The periodontal status of the teeth was improved at the six-month follow-up. Conclusion: The combination of interstitial-intralesional laser therapy, photocoagulation and LANAP was able to treat an aggressive pyogenic granuloma with tooth preservation.
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Pérdida de Hueso Alveolar , Granuloma Piogénico , Terapia por Láser , Adolescente , Pérdida de Hueso Alveolar/complicaciones , Pérdida de Hueso Alveolar/cirugía , Granuloma Piogénico/etiología , Granuloma Piogénico/patología , Granuloma Piogénico/cirugía , Humanos , Terapia por Láser/efectos adversos , Terapia por Láser/métodos , Láseres de Semiconductores/uso terapéutico , Masculino , Diente Molar/patologíaRESUMEN
OBJECTIVE: Implication of human caspase-4 in periodontitis and in sensing periodontal pathogens by gingival epithelial cells (GECs) is unclear. This study aimed to determine caspase-4 and interleukin (IL)-18 expressions in gingival tissues affected with periodontitis and to investigate caspase-4 involvement in mediating innate immune responses in GECs. DESIGN: Ex vivo, caspase-4 and IL-18 expressions in gingival biopsies, obtained from healthy participants with periodontitis or clinically healthy gingiva (N = 20 each), were determined by immunohistochemistry. In vitro, caspase-4 activation in cultured GECs stimulated with Porphyromonas gingivalis or Fusobacterium nucleatum was analyzed by immunoblotting. mRNA expressions of human ß-defensin-2 (hBD-2), IL-8, and IL-18 in stimulated GECs in the presence or absence of a caspase-4 inhibitor were assayed by RT-qPCR. RESULTS: Ex vivo, compared with healthy gingival epithelium, the epithelium affected with periodontitis displayed a significant decrease in caspase-4 expression (P = 0.015), whereas IL-18 expression was significantly increased (P = 0.012). Moreover, the expression of caspase-4, but not IL-18, was found to be a predictor of periodontitis (P = 0.007). In vitro, caspase-4 was activated in cultured GECs challenged with P. gingivalis, but not F. nucleatum. mRNA upregulations of hBD-2, IL-8, and IL-18 upon P. gingivalis stimulation were significantly reduced when caspase-4 was inhibited (P < 0.05), whereas the inhibitor failed to suppress those inductions by F. nucleatum. CONCLUSIONS: Caspase-4 expression is diminished in the epithelium affected with periodontitis while that of IL-18 is enhanced. Caspase-4 activation in P. gingivalis-infected GECs upregulates the three innate immune effector molecules, suggesting a possible sensing mechanism of caspase-4 in GECs in periodontal disease pathogenesis.
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Infecciones por Bacteroidaceae , Caspasas Iniciadoras , Encía , Periodontitis , Porphyromonas gingivalis , Infecciones por Bacteroidaceae/enzimología , Infecciones por Bacteroidaceae/microbiología , Infecciones por Bacteroidaceae/patología , Caspasas Iniciadoras/biosíntesis , Células Cultivadas , Epitelio/enzimología , Epitelio/microbiología , Epitelio/patología , Encía/enzimología , Encía/microbiología , Encía/patología , Humanos , Interleucina-18/biosíntesis , Interleucina-8/biosíntesis , Periodontitis/enzimología , Periodontitis/microbiología , Periodontitis/patología , Porphyromonas gingivalis/metabolismo , ARN Mensajero/metabolismoRESUMEN
The potential benefits of natural plant extracts have received attention in recent years, encouraging the development of natural products that effectively treat various diseases. This is the first report on establishing callus and cell suspension cultures of Rhinacanthus nasutus (L.) Kurz. A yellow friable callus was successfully induced from in vitro leaf explants on Murashige and Skoog medium supplemented with 1 mg/L 2,4-dichlorophenoxyacetic acid and 1 mg/L 1-naphthalene acetic acid. A selected friable callus line was used to establish the cell suspension culture with the same medium. The antioxidant assays showed that the leaf- and ethanolic-suspension-cultured cell (SCC) extracts exhibited high antioxidant potential. In addition, the in vitro cytotoxicity revealed by the MTT assay demonstrated potent antiproliferative effects against the oral cancer cell lines ORL-48 and ORL-136 in a dose-dependent manner. Several groups of compounds, including terpenoids, phenolics, flavonoids, quinones, and stilbenes, were identified by UHPLC-QToF-MS, with the same compounds detected in leaf and SCC extracts, including austroinulin, lucidenic acid, esculetin, embelin, and quercetin 3-(2â³-p-hydroxybenzoyl-4â³-p-coumarylrhamnoside). The present study suggests the value of further investigations for phytochemical production using R. nasutus cell suspension culture.
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This study investigated the prevalence of human papillomavirus (HPV) infection in oral squamous cell carcinoma (OSCC) cases, as well as the association between HPV presence and p16INK4a expression, in Thai patients with OSCC. Eighty-one formalin-fixed paraffin-embedded specimens of OSCC were obtained. DNA extraction was performed; this was followed by nested polymerase chain reaction analysis to determine HPV DNA status, using consensus primers for the L1 region of HPV. HPV subtypes were determined by DNA sequencing. HPV-positive specimens and HPV-negative specimens from age- and sex-matched patients were subjected to immunohistochemical analysis to determine p16INK4a expression status. Of the 81 OSCC specimens, eight (9.9%) exhibited HPV DNA; DNA sequencing confirmed that the viral subtype was HPV-18 in all eight specimens. These eight HPV-positive specimens, as well as eight HPV-negative specimens from age- and sex-matched patients, were subjected to immunohistochemical analysis to determine p16INK4a expression status. Three of eight (37.8%) HPV-positive specimens and three of eight (37.8%) HPV-negative specimens showed positive p16INK4a expression findings. However, we did not find a significant association between HPV status and p16INK4a expression status in our OSCC samples. In conclusion, the prevalence of high-risk HPV was low in this group of OSCC patients; no association between HPV status and p16INK4a expression status was identified.
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Alphapapillomavirus , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Neoplasias de la Boca , Infecciones por Papillomavirus , Carcinoma de Células Escamosas de Cabeza y Cuello , Alphapapillomavirus/genética , Alphapapillomavirus/aislamiento & purificación , Biomarcadores de Tumor/análisis , Inhibidor p16 de la Quinasa Dependiente de Ciclina/análisis , ADN Viral/análisis , Humanos , Neoplasias de la Boca/diagnóstico , Papillomaviridae/genética , Infecciones por Papillomavirus/diagnóstico , Carcinoma de Células Escamosas de Cabeza y Cuello/diagnóstico , Tailandia/epidemiologíaRESUMEN
OBJECTIVES: The aim of this study was to determine the prevalence and clinical features of pigmented oral lesions from Thailand. MATERIALS AND METHODS: Biopsy records of the Department of Oral Pathology, Chulalongkorn University, Department of Oral Diagnosis, KhonKaen University, Department of Oral Biology and Oral Diagnostic Sciences, Chiangmai University, Department of Stomatology, Prince of Songkla University, and Rangsit University were reviewed for oral pigmented lesions diagnosed during 1999 to 2019. Demographic data were culled from the biopsy records. Ages of the patients were subdivided into 10-year intervals. Locations of the lesions were classified as gingiva, labial/buccal mucosa, palate, floor of the mouth, tongue, as well as the combination of sites. Data were analyzed by descriptive statistics using SPSS version 20.0. RESULTS: Of the 47,175 accessioned cases, 241 cases (0.51%) were diagnosed in the category of pigmented oral lesions. The age of the patients ranged from 1 month to 88 years with the mean ± standard deviation = 38.74 ± 20.96 years. Regarding gender, 172 patients (71.37%) with pigmented lesions were females, while 69 patients (28.63%) were males. The female-to-male ratio was 2.49:1. The majority of the pigmented lesions were encountered at the gingiva (29.88%) followed by labial/buccal mucosa (26.97%), palate (14.94%), lip (10.79%), alveolar mucosa (9.54%), and others (7.88%), respectively. The three most common pigmented oral lesions in the present study were nevus (39.83%), followed by melanotic macule (28.63%) and amalgam tattoo (17.43%), respectively. CONCLUSIONS: The most common pigmented oral lesion in the present study is nevus. Demographic data of the patients in the present study are in accordance with previous studies with minor differences. Even though pigmented lesions of the oral cavity constitute a small portion of the oral pathology biopsies, accurate diagnosis is important since there is an overlap in clinical appearance of benign pigmented lesions and melanoma.
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A variety of black-pigmented lesions of the oral cavity can be found, ranging from harmless benign lesions such as melanotic macule, smoker's melanosis, amalgam/graphite tattoos, and pigmented nevus to a life-threatening oral malignant melanoma. Oral melanoma is a rare and aggressive malignant tumor that originates from melanocytes' proliferation and accounts for only 0.5% of all oral malignancies. The etiology is unknown. Most oral melanomas are present at the palate and the upper alveolar ridge, whereas occurrences at the buccal mucosa, the lower alveolar ridge, and the lip are rare, with only a few reports in the literature. The diagnosis is confirmed by a biopsy. The prognosis is poor, with a 5-year survival rate of ~20%. In this report, we present a case of large oral melanoma at the right buccal mucosa involving the right lower alveolar ridge and lip commissure, which are relatively unusual locations for oral melanoma. In addition, immunohistochemical markers used for diagnostic, therapeutic, and prognostic decision-making of oral melanoma are also discussed.
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Guided bone regeneration (GBR) is an effective alveolar ridge reconstruction technique used before or at implant placement. The combination of various barrier membranes and bone substitutes has been employed. This study aimed to perform a preliminarily evaluation of the safety and performance of a new nonabsorbable bi-layered porous polyethylene (PPE) membrane, in combination with a freeze-dried cortical bone allograft in posterior mandibular ridge augmentation. Fifteen adults who had combined posterior mandibular defects were included for ridge augmentation via GBR using PPE membrane and allograft before implant placement. The keratinized mucosa width (KW), ridge width (RW), ridge height (RH), distance from measurement matrix to bone (DMB), and horizontal alveolar width at 14.0 mm apical to the occlusal plane (HAW) were clinically measured at 15 intended implant sites before and after the augmentation. Fifteen biopsy specimens were harvested at the implant sites for histological analysis. All the subjects completed the whole study. The KW and RH showed minor gains by 0.2 ± 1.4 mm and 0.9 ± 2.3 mm respectively; however, no statistically significant differences were found between, before, and after the augmentation (P > 0.05). In contrast, the RW and HAW significantly increased by 4.8 ± 1.6 mm and 2.3 ± 1.7 mm, respectively, (P ≤ 0.001), while DMB significantly decreased by 1.0 ± 0.8 mm after treatment (P < 0.001). Histological analysis revealed that allograft underwent active bone remodeling. The PPE membrane was adequately safe and efficient to use with allograft in GBR for the reconstruction of combined ridge defects. Although some complications were observed, these were manageable and subsequently lead to successful implant placement for all the subjects. However, further randomized controlled trials are still needed to confirm these findings.
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Aumento de la Cresta Alveolar , Implantes Dentales , Regeneración Ósea , Trasplante Óseo , Implantación Dental Endoósea , Polietileno , PorosidadRESUMEN
BACKGROUND: Survivin is an inhibitor of apoptosis protein. Heat shock protein 90 (Hsp90) is a molecular chaperone that is involved in protein folding and maturation. Alterations in the expression of survivin and Hsp90 have been reported in several chronic inflammatory diseases. No study has evaluated the expression of survivin and Hsp90 in the same lesion of oral lichen planus (OLP). The objective of this study was to investigate the expression of survivin and Hsp90 in biopsy specimens of patients with OLP and controls. METHOD: Formalin-fixed and paraffin-embedded biopsy specimens from 29 patients with OLP and 29 healthy subjects were used in this study. Immunohistochemical methods were used to detect the expression of survivin and Hsp90 in the oral epithelia of these two groups. The distributions of positively stained epithelial cells were evaluated with a semiquantitative method, using an immunostaining score system. RESULTS: Expression of survivin and Hsp90 in oral epithelia of patients with OLP was significantly different in comparison with that in controls (P = 0.001 and P < 0.001 respectively). These differences were in the direction towards reduction in the expression of survivin and Hsp90 in the oral epithelia of patients with OLP. CONCLUSION: Our results provided additional evidence that alterations in the expression of survivin and Hsp90 in oral epithelia might be associated with pathological stress, such as chronic inflammation, in patients with OLP.
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Proteínas Reguladoras de la Apoptosis/análisis , Proteínas HSP90 de Choque Térmico/análisis , Liquen Plano Oral/patología , Proteínas Asociadas a Microtúbulos/análisis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores/análisis , Biopsia , Núcleo Celular/patología , Citoplasma/patología , Células Epiteliales/patología , Epitelio/patología , Femenino , Humanos , Inmunohistoquímica , Proteínas Inhibidoras de la Apoptosis , Masculino , Persona de Mediana Edad , Mucosa Bucal/patología , Survivin , Adulto JovenRESUMEN
This study examined and compared wound healing between Thai propolis product and calcium hydroxide paste as pulp-capping agents after partial pulpotomy in New Zealand white rabbits. Forty incisor teeth from 10 rabbits were treated. Thirty-six teeth received class V cavity preparations with partial pulpotomy and application of either propolis or calcium hydroxide paste. Similar cavity preparations were performed in 2 teeth without any capping material as a positive control, whereas 2 teeth without the cavity preparation served as a negative control. Histological evaluation showed that both groups had dentin bridge formation. Dentinal tubules in the dentin bridge were more orderly arranged in the Thai propolis group than in the calcium hydroxide group. Wound healing and the median number of hyperemic blood vessels were not statistically significant different between the 2 groups. Thai propolis product may be used as a pulp-capping agent.
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Hidróxido de Calcio/uso terapéutico , Pulpa Dental/efectos de los fármacos , Própolis/uso terapéutico , Pulpotomía/veterinaria , Cicatrización de Heridas , Animales , Pulpa Dental/lesiones , Incisivo/cirugía , Conejos , Distribución Aleatoria , Tailandia , Cicatrización de Heridas/efectos de los fármacosRESUMEN
Oral lichen planus (OLP) is considered as a chronic inflammatory immune-mediated disease causing oral mucosal damage and ulcerations. Accumulated data support the involvement of cell-mediated immune dysfunction in the development of OLP. However, the connection between neuroendocrine system and oral immune response in OLP patients has never been clarified. Melatonin is considered as a major chronobiotic hormone produced mainly by the pineal gland. This gland is recognized as a regulator of circadian rhythm and a sensor in the immune response through the NF-kB transduction pathway. It was suggested that pineal-derived melatonin and extra-pineal melatonin synthesized at the site of inflamed lesion might play a role in inflammatory response. According to our immunohistochemical study, expression of melatonin could be detected in human oral mucosa. In addition, increased levels of melatonin were observed in inflamed oral mucosa of OLP patients. We hypothesize that chronic inflammation possibly induces the local biosynthesis of melatonin in inflamed oral mucosa. We also speculate that melatonin in oral mucosa may play a cytoprotective role through its anti-oxidative and anti-inflammatory properties. Moreover, melatonin may play an immunomodulatory role in relation to pathogenesis of OLP. Our hypothesis provides a new implication for upcoming research on the connection between circadian neuroendocrine network and immune response in oral mucosal compartments.
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Liquen Plano Oral/metabolismo , Melatonina/fisiología , Animales , Ritmo Circadiano , Femenino , Hormonas/metabolismo , Humanos , Sistema Inmunológico , Inflamación , Persona de Mediana Edad , Modelos Teóricos , Mucosa Bucal/patología , FN-kappa B/metabolismo , Glándula Pineal/metabolismoRESUMEN
OBJECTIVE: The existence of extra-pineal melatonin has been observed in various tissues. No prior studies of melatonin in human oral mucosal tissue under the condition of chronic inflammation have been reported. The aim of this study was to investigate the presence of melatonin in oral mucosal tissue of patients with oral lichen planus (OLP) which was considered as a chronic inflammatory immune-mediated disease causing oral mucosal damage and ulcerations. MATERIALS AND METHODS: Sections from formalin-fixed and paraffin-embedded oral mucosal tissue of OLP patients (n=30), and control subjects (n=30) were used in this study. Immunohistochemical staining was performed and the semiquantitative scoring system was used to assess the levels of arylalkylamine-N-acetyltransferase (AANAT: a rate-limiting enzyme in the biosynthesis pathway of melatonin), melatonin, and melatonin receptor 1 (MT1) in oral mucosa of OLP patients and normal oral mucosa of control subjects. RESULTS: AANAT, melatonin, and MT1were detected in oral mucosal tissue of OLP patients and control subjects. Immunostaining scores of AANAT, melatonin, and MT1 in oral mucosal tissue of OLP patients were significantly higher than those in control subjects (p=0.002, p<0.001, and p=0.031, respectively). CONCLUSIONS: Increased levels of AANAT, melatonin, and MT1 in the inflamed oral mucosal tissue of OLP patients imply that chronic inflammation may induce the local biosynthesis of melatonin via AANAT, and may enhance the action of melatonin via MT1.
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Inflamación/metabolismo , Liquen Plano Oral/metabolismo , Melatonina/biosíntesis , Mucosa Bucal/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , N-Acetiltransferasa de Arilalquilamina/metabolismo , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana EdadRESUMEN
Pemphigus vulgaris (PV) is a serious mucocutaneous disease that be fatal if left untreated. The oral mucosa is often the first site to be affected by the disease. It is thus important that the dentist is able to recognize oral manifestations of PV and refer appropriately. Although oral PV is a well-characterized condition, the disease characteristics of patients in Thailand have not been previously reported. Here, we describe patient and lesion characteristics of 18 cases of oral PV. For these 18 cases, the mean age was 38 years, and the male:female ratio was 1:2. The most commonly affected sites were the gingiva and buccal mucosa, and the duration of disease was approximately one year. Medications previously used included corticosteroids and interferon, and nine patients reported systemic disease. Histopathologic examination with/without direct immunofluorescence was the method of diagnosis in all cases.
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Enfermedades de la Boca/patología , Pénfigo/patología , Adolescente , Corticoesteroides/uso terapéutico , Adulto , Antiinflamatorios/uso terapéutico , Femenino , Encía/patología , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Boca/tratamiento farmacológico , Mucosa Bucal/patología , Pénfigo/tratamiento farmacológico , Estudios Retrospectivos , TailandiaRESUMEN
A member of the p53 family, p73, has several isoforms and differentially regulates transcription of genes involved in the control of the cell cycle and apoptosis. We have previously shown efficient and p53-independent, tumor-specific cell death induced by the viral proteins E1A and Apoptin. Here, we demonstrate that the induction of apoptosis by these viral proteins involves activation of TAp73. Both E1A and Apoptin induced expression of endogenous TAp73 and the p53/p73 BH3-only pro-apoptotic target, PUMA, independently of the p53 function. Furthermore, exogenous expression of TAp73 isoforms, particularly TAp73beta, sensitized cells to killing by both E1A and Apoptin, while expression of DeltaNp73alpha blocked this activity. Besides, knockout of the p73 regulator, c-Abl, attenuated E1A-induced apoptosis. In accordance with the role of p73 in apoptosis induced by these viral proteins, overexpression of TAp73beta strongly induced apoptosis in p53-deficient cancer cells in vitro and in HNSCC xenografts. Using a doxycycline-inducible system, we provide evidence for target selectivity and significant differences in protein stability for specific p73 isoforms, suggesting a diverse and pivotal role for p73 in response to various genotoxic agents. Collectively, our data show that in the absence of the p53 function, viral proteins E1A and Apoptin utilize the p73 pathway to induce efficient tumor cell death.