Expression level and proteolytic activity of MMP-2 and MMP-9 in dental follicles, dentigerous cysts, odontogenic keratocysts and unicystic ameloblastomas.

Matrix metalloproteinases (MMPs) are involved in remodeling the extracellular matrix, but also participate in the development of physiopathologic processes. As they are overexpressed in different types of epithelial cancers, it has been suggested that their level expression could explain the different biological behavior between odontogenic cysts and tumors. Here, we compared the expression level and proteolytic activities of MMP-2 and MMP-9 in dental follicles, dentigerous cysts, odontogenic keratocysts and unicystic ameloblastomas. We found similar expression of MMP-2 in all tissues, but a higher activity in cystic and tumor lesions than follicles. On the other hand, MMP-9 expression and activity was greater in cysts and ameloblastoma than in follicles. However, no differences were found in expression or activity of both MMPs between cystic and tumor injuries, suggesting that they could participate in the growth of these lesions, but they cannot define their different biological behavior.

Overexpression and extra-mitochondrial localization of the chaperonin Hsp60 in ameloblastoma.

OBJECTIVES: Ameloblastoma is an odontogenic neoplasm of the mandible and maxilla with various histological types and subtypes. It has been reported that some ameloblastomas could arise from dentigerous cyst walls; thus, the development of ameloblastoma from dentigerous cysts may be due to differential protein expression. Our aim was to identify a membrane protein that is differentially expressed in ameloblastomas with respect to dentigerous cysts. METHODS: We analyzed the SDS-PAGE profiles of membrane proteins from ameloblastomas and dentigerous cysts. The protein in a band present in the ameloblastoma sample, but apparently absent in the dentigerous cyst sample was identified via mass spectrometry as the chaperonin Hsp60. We used western blotting and immunohistochemistry to analyze its overexpression and localization in ameloblastoma. RESULTS: We found a differential band of 95 kDa in the membrane proteins of ameloblastoma. In this band, the chaperonin Hsp60 was identified, and its overexpression was corroborated using western blotting and immunohistochemistry. Hsp60 was localized in the plasma membrane of all ameloblastoma samples studied; in addition, it was found in the cell nucleus of the plexiform subtype of conventional ameloblastoma. CONCLUSIONS: Our results suggest that Hsp60 may be involved in ameloblastoma development, and could therefore be a potential therapeutic target for ameloblastoma treatment.

Sublingual dermoid cyst in an infant: A case report and review of the literature.

Dermoid cysts usually occur later in the second decade of life; we present the approach of an unusual case of an infant who presented a cyst within the oral cavity, which is important because it can be confused with other pathologies.

Lipoma oral: Revisión de literatura y reporte de caso / Oral lipoma: Review of literature and case report

Resumen Los lipomas son considerados los tumores de origen mesenquimatoso más comunes del tejido blando; de ellos el 13% del total se ubican en cabeza y cuello, pero es difícil encontrarlos en la región oral y maxilofacial. La localización más común de lipomas dentro de la región oral y maxilofacial ha sido reportada en la mucosa bucal, lengua y piso de boca. Los lipomas son neoplasias que se presentan típicamente como una masa suave, de superficie lisa, nodular, amarillenta y asintomática. Histopatológicamente, el lipoma clásico asemeja un tejido normal adiposo y tiene múltiples variantes. Este artículo presenta el reporte de caso de un lipoma oral extenso en un paciente femenino de 46 años de edad en la mucosa yugal, tratado quirúrgicamente con adecuada evolución. Asimismo se realiza la revisión de literatura con sus variantes histopatológicas.

Abstract Lipomas are considered the most frequent mesenchymal tumors of soft tissue, 13% are located in head and neck but it´s difficult to find them in the oral and maxillofacial region. The most common location of lipomas within the oral and maxillofacial region has been reported in the buccal mucosa, tongue and floor of the mouth. Lipomas are neoplasias that typically present as a soft, smooth-surfaced, nodular, yellowish, and asymptomatic mass. Histopathologically, the classical lipoma resembles normal adipose tissue and it has multiple variants. This article presents a case report of a relatively large oral classical lipoma in a 46 year-old woman on mandibular buccal vestibule, along with a review of the literature and its histopatho-logical variants.

PD-1, TIM-3, and LAG-3 Expression in T Cells in a Patient with Recurrent Ossifying Fibroma: A Case Report.

Central ossifying fibroma is a benign, slow-growing tumor of mesenchymal origin with a predilection for the mandibular premolar and molar areas. The immunophenotype of T cells involved in the antitumor response against this benign tumor is unknown. In this case report, we described a case of a 48-year-old woman presenting with a very large recurrent ossifying fibroma in the mandible, which was successfully treated with hemimaxillectomy. In addition, we evaluated the expression of programmed cell death 1 receptor (PD-1), lymphocyte activation gene-3 (LAG-3), T cell immunoglobulin and mucin-domain containing-3 (TIM-3), cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), CD69 (activation inducer molecule), and CD25 (α chain of the high-affinity IL-2 receptor) in T cell populations from the tumor and peripheral blood of this uncommon lesion. The patient presented recurrent ossifying fibroma, and the tumor-infiltrating and peripheral blood T cells showed expression of PD-1, LAG-3, and TIM-3, suggesting an exhausted T cell response.

Establishment and characterization of a cell population derived from a dentigerous cyst.

BACKGROUND: Dentigerous cyst (DC) occurs in approximately 20% of jaw cysts, being the second major common odontogenic cyst, after radicular cyst. This oral lesion has the ability to destroy maxillary bones and could be the origin of several odontogenic tumors. However, molecules implicated in its pathogenesis as well as those involved in its neoplastic transformation remain unknown. Here, we established a cell population derived from a DC as an in vitro model for the study of this oral lesion. METHODS: Cell culture was performed from a DC from a 44-year-old male. Cells were cultured at 37°C in DMEM/F12 medium containing 10% fetal bovine serum. Expression of epithelial markers was analyzed by Western blot and immunofluorescence. Ultrastructural characterization was carried out by transmission electron microscopy. Conditioned media were obtained and characterized by zymography and Western blot. RESULTS: Cells showed spindle-shaped morphology, but they express epithelial markers, such as cytokeratins and the odontogenic ameloblast-associated protein. The ultrastructural analysis showed well-formed desmosomes present in adhering contiguous cells, confirming the epithelial lineage of this cell population. Cells also contain several vesicles adjacent to plasma membrane, suggesting an active secretion. Indeed, the analysis of the conditioned medium revealed the presence of several secreted proteins, among them the matrix metalloproteinase-2. CONCLUSIONS: Our work provides a useful model to identify the molecular mechanisms involved in the pathogenesis of DC.

Heridas por mordedura animal en la región maxilofacial: revisión de literatura y presentación de casos / Animal bite wounds in the maxillofacial region: a review of the literature and case reports

Las heridas por mordida en la región maxilofacial son relativamentecomunes y se consideran de tratamiento complejo; son contaminadas con una flora oral bacteriana única y, en ocasiones, tienen resultados estéticos devastadores. Las heridas pueden ser ocasionadas por animales domésticos, salvajes y humanos. El clínico debe tener una comprensión multidisciplinaria del manejo de las mismas, incluyendo el abordaje médico, quirúrgico, viral, bacteriológico y la secuencia propia del tratamiento. Se presenta una revisión de la literatura, así como casos clínicos para el tratamiento integral de este tipo de trauma.

Bite wounds in the maxillofacial region are relatively common and are regarded as diffi cult to treat given the associated contamination with what is a unique polymicrobial inoculum. The aesthetic consequences can occasionally prove devastating. The wounds can be caused by both domestic and wild animals, as well as by humans. Clinicians need to have a multidisciplinary understanding of how to manage such wounds, including surgical, medical, virological, and bacteriological aspects, and the proper sequence of treatment. We present a review of the literature and a number of clinical cases for the comprehensive management of this type of trauma.

Expression of the transcription factor PITX2 in ameloblastic carcinoma.

Ameloblastic carcinoma is a rare odontogenic tumour that combines the histological features of ameloblastoma with cytological atypia. Until 2005, the incidence of ameloblastic carcinoma was unknown, and since then, fewer than 60 cases have been reported. These tumours may originate from pre-existing tumours or cysts, or they arise de novo from the activation or transformation of embryological cells. PITX2 is a transcription factor that is a product and regulator of the WNT cell signalling pathway, which has been involved in development of several tumours. To analyse whether PITX2 could be involved in the biological behaviour of ameloblastic carcinoma, we analysed the expression of this transcription factor in a sample of this tumour and nine benign ameloblastomas to compare. The results of Western blotting and RT-PCR analyses were positive, and considering the hundreds of genes that PITX2 regulates, we believe that its expression could be intimately linked to the behaviour of ameloblastic carcinoma and possibly other odontogenic lesions.

Adenoma pleomorfo del paladar: reporte de un caso y revisión de la literatura / Pleomorphic adenoma of the palate: report of a case and review of the literature

El adenoma pleomorfo es el tumor benigno más frecuente de lasglándulas salivales. Su localización principalmente es en la glándula parótida, pero cuando aparece en una glándula salival menor, el paladar es su localización más común. Presenta un crecimiento lento y continuo; clínicamente se presenta como un nódulo o tumor asintomático, firme y bien delimitado. El diagnóstico se realiza mediante biopsia por aspiración con aguja fi na o biopsia escisional de la lesión, siendo de gran importancia debido a que a pesar de ser una tumoración benigna, en ocasiones puede presentar transformación maligna. El tratamiento consiste en la exéresis completa de la lesión con márgenes sanos. Se presenta el caso de un paciente masculino de 40 años, con una masa en el paladar duro y blando de seis años de evolución. Tras la exéresiscompleta de la lesión, el estudio histopatológico confirmó el diagnósticode adenoma pleomorfo

Pleomorphic adenomas are the most common benign tumor of the minor salivary glands. They are primarily found in the parotid gland, except when they appear in a minor salivary gland, in which case the palate is the most common site. They display a slow, steady growth. Clinically the adenoma appears as a fi rm, well-defi ned, asymptomatic nodule or tumor. Diagnosis is confi rmed by means of fi ne-needle aspiration biopsy or excisional biopsy of the lesion. It is extremely important that they are tested given that, despite their being a benign tumor, they can sometimes become malignant. Treatment consists of the complete excision of the lesion with clean surgical margins. We report the case of a 40-year-old male patient with a mass in the hard and soft palate that had evolved over a period of six years. Following the complete excision of the le-sion, histopathology confi rmed the diagnosis of pleomorphic adenoma.

Identification of proteins with increased levels in ameloblastic carcinoma.

PURPOSE: The comparative proteomic approach by a combination of 2-dimensional electrophoresis and matrix-assisted laser desorption-ionization-time of flight mass spectrometry (MS) analysis is an attractive strategy for the discovery of cancer biomarkers and therapeutic targets. The identification of protein biomarkers associated with ameloblastic carcinoma (AC), a malignant epithelial odontogenic tumor, will potentially improve the diagnostic and prognostic accuracy for this malignant neoplasm. The aim of the present study was to identify highly expressed proteins in AC that could be considered as potential biomarkers. MATERIALS AND METHODS: The protein profile of an AC was compared with the protein profiles of 3 cases of benign ameloblastoma. Proteins that showed increased levels in AC were identified using MS, and the augmented amount of some of these proteins in the malignant lesion was confirmed by Western blot or immunohistochemistry. RESULTS: We detected a total of 782 spots in the protein profile of AC, and 19 of them, showing elevated levels compared with benign ameloblastoma, were identified using MS. These proteins have been implicated in several cellular functions, such as cell structure, metabolism, stress response, and signal transduction. CONCLUSIONS: The increased expression of the identified proteins and the minor expression of some proteins that might inhibit tumor progression could be involved in the evolution from a benign lesion to carcinoma.

Adenoma pleomorfo palatino: presentación de escisión alterna con descenso de colgajo palatino de espesor total / Pleomorphic adenoma of the palate: presentation of a surgical excision technique involving the elevation of a full-thickness palatal flap

El adenoma pleomorfo es la neoplasia benigna de glándulas salivales más común, tanto de glándulas mayores como de menores. La localización intraoral más frecuente es entre los límites del paladar duro y paladar blando y puede llegar a impedir una adecuada masticación, fonación, así como a disminuir el libre paso de alimentos. La recurrencia de dichas lesiones es alta si no llevamos a cabo una técnica quirúrgica adecuada, tanto para remover la lesión en su totalidad como para respetar la cápsula que la rodea. En el presente artículo, se presenta un caso clínico realizado en el Hospital Juárez de México, de una paciente con lesión de adenoma pleomorfo palatino de tamaño considerable, en donde se realizó la escisión quirúrgica de manera alterna con un descenso de colgajo palatino de espesor total y remoción completa de la lesión, conservando en todo momento su cápsula. En el seguimiento a largo plazo no se observaron recurrencias, neoformaciones, y encontramos una adecuada remodelación y adaptación del colgajo en su posición original.

Pleomorphic adenoma is the most common benign neoplasm of both the major and minor salivary glands. The most frequently intraoral location is between the boundaries of the soft and hard palates. It can impede proper mastication and phonation, and prevent food from passing freely. The recurrence rate for this kind of lesion is high if a suitable surgical technique is not used, in terms of both removing the entire lesion and ensuring that the capsule that surrounds it is not compromised. In this article, we present a clinical case study carried out at the Juarez Hospital, involving a female patient with a large pleomorphic adenoma lesion. We performed an alternative surgical excision involving the elevation of a full-thickness palatal flap and complete removal of the lesion, whilst preserving its capsule. In the long-term follow up, no recurrences or neoformations were observed and we found an adequate remodeling and adaptation of the flap into its original position.

Modificación de procedimiento Dautrey en dislocación recurrente mandibular / Dautrey procedure modification, in recurrent mandibular dislocation

El manejo de la dislocación recurrente mandibular, puede representar un reto para el Cirujano Maxilofacial. La decisión tomada debe ser de acuerdo a las demandas de cada caso en particular. El presente caso fue tratado quirúrgicamente mediante el procedimiento Dautrey, debido a la dislocación recurrente crónica unilateral derecha de la articulación temporomandibular. Este procedimiento no perturba el movimiento funcional normal de la articulación, por otra parte previene la excursión excesiva anterior del cóndilo. La técnica quirúrgica propuesta, presenta una modificación al procedimiento original. Con resultados finales favorables para la función.

Managing recurrent dislocations of the mandible, may represent to the Maxillofacial Surgeon a challenge. The chosen decision has to be according to the demands of each case in particular. The present case is treated surgically by Dautrey procedure, because of chronic recurrent unilateral right side dislocation of the temporomandibular joint. This procedure does not disturb normal functional movement of the joint yet prevents excessive forward excursion of the condyle. The surgical technique is presented with a modification of the original procedure. With favorable final results to the function.

The orosomucoid 1 protein (α1 acid glycoprotein) is overexpressed in odontogenic myxoma.

BACKGROUND: Odontogenic myxoma (OM) is a benign, but locally invasive, neoplasm occurring in the jaws. However, the molecules implicated in its development are unknown. OM as well as Dental Follicle (DF), an odontogenic tissue surrounding the enamel organ, is derived from ectomesenchymal/mesencyhmal elements. To identify some protein that could participate in the development of this neoplasm, total proteins from OM were separated by two-dimensional electrophoresis and the profiles were compared with those obtained from DF, used as a control. RESULTS: We identified eight proteins with differential expression; two of them were downregulated and six upregulated in OM. A spot consistently overexpressed in odontogenic myxoma, with a molecular weight of 44-kDa and a pI of 3.5 was identified as the orosomucoid 1 protein. Western blot experiments confirmed the overexpression of this protein in odontogenic myxoma and immunohistochemical assays showed that this protein was mainly located in the cytoplasm of stellate and spindle-shaped cells of this neoplasm. CONCLUSION: Orosomucoid 1, which belongs to a group of acute-phase proteins, may play a role in the modulation of the immune system and possibly it influences the development of OM.

Colgajo lingual para cierre de fístula oronasal: aportación a la técnica / Lingual flap for closure of oronasal fistula: contribution to the technique

La fístula oronasal es la complicación más común posterior a una palatoplastía y frecuentemente requiere de una reparación secundaria. Se ha desarrollado una gran cantidad de técnicas quirúrgicas para su manejo, siendo una de las más populares el colgajo lingual. A pesar de la excelente vascularidad de la lengua, para asegurar la viabilidad del colgajo, éste debe ser manejado con extremo cuidado durante el procedimiento. Con este propósito sugerimos el uso de una platina acrílica en forma de herradura que aporta estabilidad e inmoviliza la lengua durante la cirugía, lo que facilita el procedimiento y ayuda a evitar errores durante el diseño y el levantamiento del colgajo(AU)

The oronasal fistula is the most common complication after a palatoplasty and it frequently needs a secondary repair. A great number of surgical techniques have been developed for the management of this condition. The lingual flap is one of the most popular treatments. In spite of the excellent vascularity of the tongue, it must be handled carefully during the procedure to assure the viability of the flap. For this reason we suggest the use of an acrylic slide in the shape of horse-shoe that improves the stability and immobilises the tongue during the surgery. This makes the procedure easier and helps to avoid mistakes during the design and the raising of the flap(AU)

Angiomyxolipoma (vascular myxolipoma) of the oral cavity. Report of a case and review of the literature.

Angiomyxolipoma is a rare tumor characterized by a proliferation of adipose tissue associated with a myxoid stroma and multiple vascular channels. To date, ten cases of angiomyxolipoma located in subcutaneous tissue, spermatic cord and subungual area have been reported in the literature. We describe the clinical and histopathologic findings of the first case of intraoral angiomyxolipoma in a 12 year-old male, as well as the utility of immunohistochemistry as a useful tool in differential diagnosis of this particular lesion with respect to other benign and malignant lesions derived from adipose tissue.

Quiste epidermoide de cuello. Presentación de un caso clínico / Epidermoid cyst of the neck. A clinical case presentation

Las lesiones quísticas pueden ser congénitas o adquiridas, cuando son de origen congénito son llamados quistes epiteliales y cuando son de origen adquirido, quistes de inclusión o quistes postraumáticos. Aunque el origen del quiste epidermoide es incierto la explicación más apropiada es que se desarrolla de restos ectodérmicos enclavados durante el cierre de la línea media de las fisuras embrionarias, se presume que proviene del primero y segundo arco branquial. Se puede localizar en cualquier parte del cuerpo, reportándose muchos casos en ovarios y testículos; siendo sólo el 7 por ciento de estos en cabeza y cuello y muy raras veces se presenta en la cavidad bucal (1 por ciento)