Eliene Carvalho da Fonseca

Expression of Bcl-2 family proteins and associated clinicopathologic factors predict survival outcome in patients with oral squamous cell carcinoma.

The aims of this study were to assess the expression levels of three proteins involved in apoptosis--Bcl-2, Bcl-X, and Bax--and evaluate their relationship with clinicopathologic features and survival in oral squamous cell carcinoma (OSCC). Immunohistochemistry was used to evaluate protein expression in 53 primary OSCCs treated by radical surgery with free margins at a single institution in 1999. Histologic specimens were graded and analyzed for perineural invasion, lymphocytic infiltrate, and pattern of invasion. Digital image analysis was performed to quantify immunostaining. Survival was analyzed using the Kaplan-Meier method and Coxs proportional hazard model. Cancer-specific 5-year survival (CSS) was 61% (56% overall survival (OS), and 51% disease-free interval (DFI)). Kaplan-Meier analysis identified pathologic stage (p=0.0007, log-rank test, OS), negative nodes status (pN) (p<0.0001, log-rank test, OS), presence of lymphocytic infiltrate (p=0.0084, log-rank test, OS), and high Bax expression (p=0.025, log-rank test, OS) to each be associated with both better OS and CSS. Tongue tumors (p=0.0179, log-rank test), worst pattern of invasion (p=0.0293, log-rank test), lack of lymphocytic infiltrate (p=0.0328, log-rank test), perineural invasion (p=0.0448, log-rank test), poorly differentiated tumors (p=0.0318, log-rank test), and low Bcl-X expression (p=0.044, log-rank test) were all associated with a low DFI. Cox regression found pN, lymphocytic infiltrate, and Bax expression to be independent prognostic factors for OS and CSS, whereas lymphocytic response and tongue tumors were predictors of DFI. Bcl-2 expression emerged as an independent marker of favorable CSS. Lymphocytic infiltrate was the most meaningful histopathologic parameter in survival analysis, whereas expression of Bcl-2 family members seems to be an important marker of a favorable prognosis in OSCC.

Evaluation of mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors

BACKGROUND Several cell types are associated with the development of cystic and tumoral odontogenic lesions. Among inflammatory cells, mast cells can be associated with their pathogenesis. The aim of this study was to analyze mast cells in periapical cysts, dentigerous cysts, and keratocystic odontogenic tumors. METHODS Tissue sections were submitted to toluidine blue staining and immunohistochemistry with antibody anti-tryptase (clone G3). Mast cells were quantitated using Image-Pro Plus software to obtain the mean number of mast cells in three regions: epithelial, superficial portion of the fibrous wall and deep portion of the fibrous wall from 20 periapical cysts, 20 dentigerous cysts (six non-inflamed and 14 inflamed) and 20 keratocystic odontogenic tumors (four non-inflamed and 16 inflamed). RESULTS The mean number of mast cells detected per lesion by immunohistochemistry (4.1) was higher than by histochemistry (1.5) (P<0.0001). Inflamed dentigerous cysts and keratocystic odontogenic tumors showed a higher mean number of mast cells than non-inflamed lesions in all regions. The deep region from all cysts showed the highest mean number of degranulated mast cells, except for non-inflamed keratocystic odontogenic tumors analyzed by immunohistochemistry. CONCLUSIONS Immunohistochemical staining detected higher number of mast cells than histochemistry. The higher number of mast cells observed in inflamed lesions could indicate the participation of these cells in the inflammatory response in odontogenic lesions. The prevalence of degranulated mast cells in the deep region suggests intense activity of these cells, possibly related to growth of cystic lesions.

Identification of growth hormone receptor in plexiform neurofibromas of patients with neurofibromatosis type 1

OBJECTIVE The aim of this study was to investigate the presence of growth hormone receptor in plexiform neurofibromas of neurofibromatosis type 1 patients. INTRODUCTION The development of multiple neurofibromas is one of the major features of neurofibromatosis type 1. Since neurofibromas commonly grow during periods of hormonal change, especially during puberty and pregnancy, it has been suggested that hormones may influence neurofibromatosis type 1 neurofibromas. A recent study showed that the majority of localized neurofibromas from neurofibromatosis type 1 patients have growth hormone receptor. METHODS Growth hormone receptor expression was investigated in 5 plexiform neurofibromas using immunohistochemistry. RESULTS Four of the 5 plexiform neurofibromas were immunopositive for growth hormone receptor. CONCLUSION This study suggests that growth hormone may influence the development of plexiform neurofibromas in patients with neurofibromatosis type 1.

Is the thymus a target organ in infectious diseases

The thymus is a central lymphoid organ, in which T cell precursors differentiate and generate most of the so-called T cell repertoire. Along with a variety of acute infectious diseases, we and others determined important changes in both microenvironmental and lymphoid compartments of the organ. For example, one major and common feature observed in acute viral, bacterial and parasitic diseases, is a depletion of cortical thymocytes, mostly those bearing the CD4-CD8 double positive phenotype. This occurs simultaneously to the relative enrichment in medullary CD4 or CD8 single positive cells, expressing high densities of the CD3 complex. Additionally we noticed a variety of changes in the thymic microenvironment (and particularly its epithelial component), comprising abnormal location of thymic epithelial cell subsets as well has a denser Ia-bearing cellular network. Moreover, the extracellular matrix network was altered with an intralobular increase of basement membrane proteins that positively correlated with the degree of thymocyte death. Lastly, anti-thymic cell antibodies were detected in both human and animal models of infectious diseases, and in some of them a phenomenon of molecular mimicry could be evidenced. Taken together, the data reviewed herein clearly show that the thymus should be regarded as a target in infectious diseases.

Leucoplasia pilosa oral: aspectos histopatológicos da fase subclínica

Oral hairy leukoplakia (OHL) is one of the most common oral manifestations of AIDS, with diagnostic and prognostic value. OHL is associated to the Epstein-Barr virus and presents clinical and histological defined characteristics. There have already been reports about a subclinical stage of OHL, although they lacked histopathologic characterization. The present study had the aim to describe the histopathological characteristics of subclinical hairy leukoplakia, as well as to carry out a comparative analysis between clinical and subclinical OHL. For that, 11 cases were analyzed - 5 biopsies from patients who presented with the lesion and 6 samples from the borders of tongues obtained in necropsies. The histopathological findings in subclinical OHL were: absence of parakeratosis and papillomatosis, mild acanthosis, ballooning cells and nuclear alterations. In situ hybridization and immunostaining were positive for EBV in the nuclear alterations identified in the histophatological analysis. Based on the identification of EBV in the nuclear alterations, it was possible to conclude that subclinical OHL, similarly to the clinical lesion, presents histopathological features that are specific and sufficient to establish the definitive diagnosis, regardless of the identification of the virus.

Evaluation of Bcl-2, Bcl-x and cleaved caspase-3 in malignant peripheral nerve sheath tumors and neurofibromas.

AIMS To study the expression of Bcl-2, Bcl-x, as well the presence of cleaved caspase-3 in neurofibromas and malignant peripheral nerve sheath tumors. The expression of Bcl-2 and Bcl-x and the presence of cleaved caspase 3 were compared to clinicopathological features of malignant peripheral nerve sheath tumors and their impact on survival rates were also investigated. MATERIALS AND METHODS The evaluation of Bcl-2, Bcl-x and cleaved caspase-3 was performed by immunohistochemistry using tissue microarrays in 28 malignant peripheral nerve sheath tumors and 38 neurofibromas. Immunoquantification was performed by computerized digital image analysis. CONCLUSIONS Apoptosis is altered in neurofibromas and mainly in malignant peripheral nerve sheath tumors. High levels of cleaved caspase-3 are more common in tumors with more aggressive histological features and it is associated with lower disease free survival of patients with malignant peripheral nerve sheath tumors.

Quality and intensity of the tissue response to two synthetic granular hydroxyapatite implanted in critical defects of rat calvaria

The objective of the present study was to evaluate the quality and intensity of the tissue response to two synthetic hydroxyapatites implanted in critical defects in the skulls of rats. Sixty animals were divided into three experimental groups: I (control), II (HA-1 = HA with 28% crystallinity) and III (HA-2 = HA with 70% crystallinity). They were sacrificed 1, 3, 6, and 9 months after implantation (n = 5 individuals per group/period). Histomorphometric analysis included i) counting of polymorphonuclear leucocytes, mast cells, macrophages and foreign body multinucleated giant cells stained with anti-lysozyme; ii) microvascular density stained with anti-Factor VIII and iii) degree of cell proliferation stained with anti-PCNA. There were no significant differences between the experimental groups in either the quality or quantity of cells in the inflammatory infiltrate, or the degree of angiogenesis and cell proliferation. We conclude that HA-1 and HA-2 are biocompatible and that the physico-chemical differences of these biomaterials did not affect cellular response.

Análise comparativa da imunoexpressão da proteína p53 (clones DO-7 e PAb-240) em carcinomas de células escamosas intrabucais e labiais

BACKGROUND: Carcinogenesis is a multifactorial process and inactivation of p53 protein is a genetic change commonly observed in oral squamous cell carcinomas (OSCC). OBJECTIVES: To analyze and compare the expression of p53 protein through antibodies DO-7 and PAb-240 in OSCC samples located in the oral cavity and lower lip. MATERIAL AND METHODS: Forty cases of OSCC were selected and divided into oral cavity and lower lip groups (20 cases each). Immunohistochemical technique was performed using antibodies DO-7 and PAb-240. Quantification of the cases was performed through digital image analysis and underwent specific statistical treatments. RESULTS: Expression of p53 protein was verified with DO-7 antibody in 13 cases (65%) of oral cavity carcinomas and in 19 cases (95%) of lower lip carcinoma. PAb-240 positivity was detected in 9 cases (45%) of oral cavity lesions and in 15 cases (75%) located in the lower lip. According to Mann-Whitney test, there were no statistically significant differences between the expressions of p53 protein in both groups, regardless of the antibody used. According to Wilcoxon test, there were statistically significant differences between the expression of DO-7 antibody and PAb-240 in each of the analyzed groups (p-value = 0.013; lower lip p-value = 0.016 - oral cavity). CONCLUSIONS: The expression of p53 protein was observed both in the oral cavity and lip OSCC, which suggests the occurrence of mutations in TP53 gene. The quantitative differences between the antibodies studied, regardless of the site of the lesions, reflect different specificity between clones DO-7 and PAb-240. Further studies are required to establish the best antibody for p53 protein in oral squamous cell carcinomas.

Análise histopatológica comparativa entre líquen plano oral e cutâneo

BACKGROUND: Lichen planus is a relatively common chronic inflammatory disease affecting skin and mucous membranes, separately or together. It frequently involves the oral cavity, with or without concomitant cutaneous compromise. Microscopically, while skin presents well characteristic aspects, oral mucosa can present variations related to local characteristics of the mucosa in the oral cavity. OBJECTIVES: To compare histopathological alterations of oral lichen planus and cutaneous lichen planus with the study of the inflammatory infiltrate components. METHODS: 59 biopsies (29 of OLP and 30 of CLP), formalin-fixed, paraffin-embedded were studied. Semi-quantitative analysis of both epidermal and dermal alterations was performed using the hematoxylin-eosin and periodic acid-Schiff stains. RESULTS: For CLP the classic aspects of orthokeratosis, wedge shaped hypergranulosis and saw tooth rete ridges were observed. Such aspects differ from those of OLP in which orthokeratosis and thickened granular layer happen less frequently; instead, acquisition of those layers is observed in places where they are usually absent. Basal cell vacuolar alteration and effacement of the epithelium-conjunctive limit prevailed in both locations (skin and oral mucosa) and lymphocytes and histiocytes were the inflammatory cells present in all cases. CONCLUSIONS: Classic alterations as compact orthokeratosis, wedge shaped hypergranulosis, saw tooth rete ridges acanthosis and basal cell vacuolar alteration associates to lymphocytes in superficial band-like pattern are diagnostic of CLP. However, for OLP, the particular own characteristics of oral mucosa in the biopsied place should be considered; also, subtler alterations of horny (light orthokeratosis) and granular (presence where it is usually absent) layers should be valued . Wedge shape pattern of hypergranulosis is rarely seen in OLP. Saw tooth rete ridges acanthosis is not frequently seen in OLP, however, basal cell vacuolar alteration is always present and associated to band-like lymphocitic infiltrate. Plasma cells can accompany lymphocytes in OLP, however, they are absent in CLP.

Investigação da LMP1 do EBV e a coinfeçcão do HPV em lesões genitais de pacientes infectados ou não pelo HIV

INTRODUCTION: Several studies have demonstrated the association between Epstein-Barr virus (EBV) and malignant neoplasias, including genital lesions, in which the human papillomavirus (HPV) is the main virus associated with both benign and malignant epithelial neoplasias. OBJECTIVE: Investigate the presence of EBV and HPV in genital lesions in HIV-infected patients (group A) or HIV non-infected patients (group B) from both genders. MATERIAL AND METHOD: We selected 126 patients and 135 anogenital lesions, comprising 67 patients (53%) and 75 lesions (56%) from group A and 59 patients (47%) and 60 lesions (44%) from group B, to histopathological and immunohistochemical analyses through latent membrane protein 1 (LMP1) monoclonal antibodies and HPV (DAKO®). RESULTS: The analysis showed that the total number of lesions with immunopositivity for HPV and for LMP1 was higher in group A (32 and 35 respectively) in comparison with B (16 and six respectively). Statistical analysis (significance level of 5%) showed that the proportions for HPV are not statistically significant (z = 1.93; value p = 0.053). However, the difference (47% in group A and 10% in B) is significant for LMP1 (z = 4.60; value p = 4.2×10-6). Similarly, the association of HPV and LMP1 (21% in group A and 7% in B) also showed a significant statistical difference (z = 2.38; value p = 0.017). CONCLUSION: The results demonstrated the possibility of synergism between EBV infection and EBV-HPV co-infection in genital epithelial lesions, mainly among HIV-infected patients. However, further investigations with a more specific and sensitive methodology are required in order to assess the real influence of EBV on the pathogenesis of genital epithelial lesions.