Glucose transporter protein 1 expression in mucoepidermoid carcinoma of salivary gland: correlation with grade of malignancy

P>Mucoepidermoid carcinoma (MEC), the most common primary salivary malignancy, shows great variability in clinical behaviour, thus demanding investigation to identify of prognostic markers. Since Warburg`s studies, unrestricted cell growth during tumorigenesis has been linked to altered metabolism, implying hypoxic stimulation of glycolysis and diminished contribution of mitochondrial oxidative phosphorylation to cellular ATP supply. Hypothesizing that the study of MEC metabolic status could lead to the discovery of prognostic markers, we investigated by immunohistochemistry the expression of glucose transporter 1 (Glut-1), mitochondrial antigen and peroxiredoxin I (Prx I) in samples of MEC from different histological grades. Our results showed that mitochondrial antigen and Prx I were expressed in the majority of the MEC cases independent of the histological grade. In contrast Glut-1 expression increased significantly as the tumours became more aggressive. These results suggested that oxidative phosphorylation may contribute to ATP supply in all stages of MEC progression, and that the relative contribution of glycolysis over mitochondria for cellular ATP supply increases during MEC progression, favouring growth under low oxygen concentration. In addition, the observed high Prx I protein levels could provide protection to tumour cells against reactive oxygen species generated as a consequence of mitochondrial function and hypoxia-reoxygenation cycling. Altogether our findings suggest that upregulation of Glut-1 and Prx I constitute successful adaptive strategies of MEC cells conferring a growth advantage over normal salivary gland cells in the unstable oxygenation tumour environment.

Expression of extracellular matrix proteins in adenomatoid odontogenic tumor

Altered expression of extracellular matrix (ECM) components has been reported in several pathologies; however, few ECM proteins have been evaluated in adenomatoid odontogenic tumor (AOT). The aim of this study was to analyze the expression and distribution of the ECM proteoglycans: biglycan and decorin; and glycoproteins: osteonectin, osteopontin, bone sialoprotein and osteocalcin in the AOT. Three-micrometer sections from paraffin-embedded specimens were evaluated employing a streptavidin-biotin immunohistochemical method with the antibodies against the proteins previously cited. Only the osteonectin was expressed in the epithelial cells. The eosinophilic amorphous material and the connective tissue showed expression of all components studied. The calcification foci expressed only osteopontin. In conclusion, the low expression of the components studied in neoplastic epithelial cells suggests that the epithelial cells act probably as stimulators of the expression by the stroma, which in turn can act as agonist or antagonist of the tumor growth. These results suggest that the components studied probably have a key role in the biological behavior of the AOT.

Development of human minor salivary glands: expression of mucins according to stage of morphogenesis

The formation of salivary glands entails the proliferation of epithelial cells from the stomatodeum into the underlying ectomesenchyme, culminating in a complex network of ducts and acinar bulbs. The extent to which mucins regulate this process is unknown, but they appear to mediate luminal space formation and maturation. Our aim was to examine mucin expression patterns during the morphogenesis of human salivary glands. Mucin expression - MUC1, 2, 3, 4, 5AC, 5B, 6, and 16 - was analyzed in specimens of developing human salivary glands, obtained from fetuses at 4-24 weeks` gestation, and fully developed salivary glands by immunohistochemistry. Expression patterns were analyzed qualitatively according to the development stage of the salivary glands. Mucins 1, 3, 4, 5B, and 16 were expressed during salivary gland development - being stronger in all ductal segments by the final phases of branching morphogenesis and in mature glands. Acinar cells were negative for most mucins, including MUC1 in mature salivary glands. Mucins 2, 5AC, and 6 were not expressed. Mucins MUC1, 3, 4, 5B, and 16 are expressed in developing human salivary glands and in mature glands, suggesting important roles in the maturation and maintenance of the ductal network.

Oral manifestations of human T-cell lymphotropic virus infection in adult patients from Brazil

Objective: Human T-cell lymphotropic virus type 1 (HTLV-1) was the first human retrovirus discovered and its pathogenesis is related to T cells infection. This study aimed to verify the presence of oral manifestations in a Brazilian population of patients who was seropositive for HTLV, and identify risk factors for oral manifestations. Subjects and methods: An assessment was made of 139 patients at the Emilio Ribas Institute of Infectious Diseases. Results: A total of 112 (80.5%) patients were HTLV-1, 26 (18.7%) were HTLV-2+. About 35.2% of patients had myelopathy/tropical spastic paraparesis (HAM/TSP), with 48 of them being HTLV-1+ and one patient was seropositive for HTLV-1 and -2. The most common oral manifestations were: xerostomia (26.8%), candidiasis (20.8%), fissured tongue (17.9%), and loss of tongue papillae (10.0%). A multivariate logistic regression analysis showed that HAM/TSP is an independent risk factor for xerostomia (P = 0.02). The patients who were HAM/TSP+ were three times more likely to develop xerostomia when compared with patients without HAM/TSP (odds ratio = 2.69, 95% confidence interval = 1.17-6.17). Conclusion: Despite the fact that the findings of this study suggest a relationship between xerostomia and HAM/TSP, more studies should be developed to show what the association would be between xerostomia presented by HTLV patients and pathogenesis of the virus.

The severity of epithelial dysplasia is associated with loss of maspin expression in actinic cheilitis

Background Prolonged exposure of the lip to sunlight may cause actinic cheilitis (AC) and squamous cell carcinoma (SCC). Maspin is a serpin with tumor suppressor functions. This work analyzed the presence and distribution of maspin in AC and lip SCC. Methods Sections from 36 cases diagnosed as AC (18 cases with mild epithelial dysplasia, 11 with moderate and 7 with severe), 18 cases diagnosed as lip SCC and 7 specimens containing normal lip vermillion epithelium were submitted for immunohistochemical analysis to detect maspin. Results All AC cases with mild and two cases with moderate dysplasia were scored 3. The remaining nine cases with moderate dysplasia were identified as score 2, whereas all cases with severe dysplasia were scored 1. Positive staining for maspin decreased from the basal layer to the surface. Among the 18 lip SCCs studied, 15 cases showed abundant staining for maspin. Epithelium adjacent to the SCCs also showed intense positive staining in all cells. Conclusions Our results suggest that the loss of maspin expression occurs from the basal layer to the surface. Lip SCCs related to solar radiation show an intense presence of maspin protein in almost all tumor cells as well as the neighboring epithelium. Fontes A, Sousa SM, Santos E, Martins MT. The severity of epithelial dysplasia is associated with loss of maspin expression in actinic cheilitis.

Differential expression of galectin-3, beta-catenin, and cyclin D1 in adenoid cystic carcinoma and polymorphous low-grade adenocarcinoma of salivary glands

Background: Galectin-3 has been implicated in tumor progression of some malignancies as thyroid, prostate, and salivary gland tumors. Recently, it has been suggested that this protein may be an important mediator of the beta-catenin/Wnt pathway. Moreover, nuclear galectin-3 expression has been implicated in cell proliferation, promoting cyclin D1 activation. Thus, the present study aimed to correlate galectin-3 expression with beta-catenin and cyclin D1 expressions in adenoid cystic carcinoma (ACC) and in polymorphous low-grade adenocarcinoma (PLGA). Methods: Fifteen formalin-fixed paraffin-embedded cases of each tumor were retrieved from the files of the Surgical Oral Pathology Service at the University of Sao Paulo and the proteins were analyzed by immunohistochemistry. Results: Adenoid cystic carcinoma showed galectin-3 immunostaining mainly in the nuclei, while PLGA revealed a positive mostly cytoplasmic reaction to galectin-3 in the largest part of tumor cells. Both tumors showed intense cytoplasmic/nuclear staining for beta-catenin in majority of cases. Cyclin D1 immunoreactivity was not detected in 14/15 PLGA and showed specific nuclear staining in 10/15 cases of ACC in more than 5% of the neoplastic cells. Cyclin D1 expression was correlated with cytoplasmic and nuclear galectin-3 expression in ACC (P < 0.05). Conclusions: These results suggest that in ACC galectin-3 may play a role in cellular proliferation through cyclin D1 activation. In addition, nuclear expression of galectin-3 in ACC may be related to a more aggressive behavior of this lesion. Although beta-catenin seems to play a role in carcinogenesis in both lesions, it seems that it does not bind to galectin-3 for cyclin D1 stimulation.

WNT-5A, but not matrix metalloproteinase 3 or beta-catenin protein, expression is related to early stages of lip carcinogenesis

Background: Oncogenic Wnt/beta-catenin signaling occurs in numerous types of cancers, but little is known about the role of the Wnt protein family member, WNT-5A, in lip carcinogenesis. The aim of this study was to investigate WNT-5A, beta-catenin, and matrix metalloproteinase (MMP)-3 protein expression in actinic cheilitis (AC), and lip squamous cell carcinoma (LSCC). Methods: Twenty-one cases of AC, and fifty-one cases of LSCC were analyzed, with normal lip mucosa used as a control. Qualitative and semi-quantitative analyses of WNT-5A, beta-catenin, and MMP-3 immunostaining pattern and cellular distribution were performed. Results: WNT-5A was observed in more than 50% of the cells, scattered in all layers of AC, in contrast to the absence of immunostaining in normal lip mucosa. AC presented a higher level of WNT-5A expression than LSCC (P = 0.0289, Fisher test), while MMP-3 immunoexpression was statistically more significant in LSCC than in AC (P = 0.0285, Fisher test). Immunolabeling of beta-catenin protein was differentially distributed between samples; the majority of AC cases (61.90%) demonstrated a membranous-cytoplasmic pattern, while a considerable number of LSCC cases (29.41%) revealed a cytoplasmic pattern, instead of the usual membranous pattern. Conclusions: The present results suggest that WNT-5A may be an important marker during initial events of AC malignant transformation, in which non-canonical and canonical Wnt/beta-catenin signaling pathways could be involved. Additionally, WNT-5A might recruit other events in LSCC, such as MMP-3 protein synthesis, as its presence is increased in established malignant processes without beta-catenin dependency.

Effect of recombinant human bone morphogenetic protein-7 (rhBMP-7) on the viability, proliferation and differentiation of osteoblast-like cells cultured on a chemically modified titanium surface

Aim: The aim of the present study was to assess the influence of the chemical characteristics and roughness of titanium surfaces on the viability, proliferation and differentiation of osteoblast-like cells cultured in a medium supplemented with recombinant human bone morphogenetic protein-7 (rhBMP-7). Material and methods: Osteo-1 cells were grown on titanium disks presenting with the following surfaces: (1) machined, (2) coarse grit-blasted and acid-attacked (SLA) and (3) chemically modified SLA (SLAmod) in the absence or presence of 20 ng/ml rhBMP-7 in culture medium. The viability and number of osteo-1 cells were evaluated after 24 h. Analyses of total protein content (TP) and alkaline phosphatase (AP) activity at 7, 14 and 21 days, collagen content at 7 and 21 days and mineralized matrix formation at 21 days were performed. Results: Cell viability (P=0.5516), cell number (P=0.3485), collagen content (P=0.1165) and mineralized matrix formation (P=0.5319) were not affected by the different surface configurations or by the addition of rhBMP-7 to the medium. Osteo-1 cells cultured on SLA surfaces showed a significant increase in TP at 21 days. The ALPase/TP ratio (P=0.00001) was affected by treatment and time. Conclusion: The results suggest that the addition of rhBMP-7 to the culture medium did not exert any effect on the viability, proliferation or differentiation of osteoblast-like cells grown on the different surfaces tested. All titanium surfaces analyzed allowed the complete expression of the osteoblast phenotype such as matrix mineralization by osteo-1 cells.

Alpha lipoic acid in burning mouth syndrome - a randomized double-blind placebo-controlled trial

The burning mouth syndrome (BMS) is a chronic condition characterized by oral burning pain in the absence of clinical abnormalities and without established therapy. The purpose of this study was to evaluate the effectiveness of alpha lipoic acid (ALA) in the management of BMS symptoms through a randomized double-blind placebo-controlled trial. Thirty-eight patients (34 women and four men, median age 62.9 years, range 36-78) were included and 31 completed the study. The patients were randomized into two cycles of treatment: one with alpha lipoic acid and one with placebo both administered in identical capsules. These cycles were separated by a washout period of 20 days. The oral symptoms and the treatment response were assessed using a 100-mm visual analog scale before and after each cycle and the global perceived effect score, using a 5-point scale after each treatment cycle. The level of reduction on burning was significant for both treatments (paired t-test: P < 0.05; rp = 0.011; ral < 0.001). Considering the two cycles together, 22 patients reported at least some improvement after ALA use and 23 patients after placebo. Comparison of the oral assessment scores of the two cycles failed to demonstrate the effectiveness of ALA over placebo (t-test: P > 0.05; r = 0.75).

Dyskeratosis Congenita - Report of a Case with Emphasis on Gingival Aspects

A case of dyskeratosis congenita (DC) of an 11-year-old male is reported. He presented with the characteristic clinical triad of reticular pigmentation of the skin, dystrophic nails and oral lesions, and up to the present he had not developed hematological compromise. Oral lesions consisted of extensive tongue erosions and keratosis, and exuberant gingivitis associated. Appropriate periodontal treatment was performed with discrete improvement only. We emphasize that severe gingival inflammation, although infrequent, may represent an alteration specific to DC and therefore should be considered as an additional sign of this syndrome.

Peroxiredoxin I is differentially expressed in multiple myelomas and in plasmablastic lymphomas

BACKGROUND: Plasmablastic lymphoma (PBL) and multiple myeloma (MM) are B cell-derived malignancies that share many morphologic and immunophenotypic traits, making the differential diagnosis particularly complicated. We have recently demonstrated that peroxiredoxin I (PrdxI) is expressed in plasma cells but not in B lymphocytes, suggesting that its expression is development-associated. AIM: To analyze PrdxI expression in PBL and in MM in order to study its utilization as an additional diagnostic molecular tool. METHODS AND RESULTS: Eight cases of PBL and nine of MM were studied by immunohistochemistry. We have demonstrated that PrdxI expression is closely connected with the immunoglobulin production capacity of the cells, which means high in MM, but absent in PBL cases, except one, wherein few cells were stained. CONCLUSIONS: We hypothesize PrdxI as a component of the unfolded protein response (UPR), an adaptive pathway essential for plasma cell differentiation. As we have not detected immunoglobulin in our PBL cases, we suggest that UPR was not activated in the cells, accounting for the impediment of the developmental process, and for the inhibition of PrdxI expression observed. PrdxI could be considered an additional plasma cell functional marker and could also be speculated as a therapeutic target in the treatment of MM. Oral Diseases (2008) 14, 741-746

Herpes viruses in periodontal compromised sites: comparison between HIV-positive and -negative patients

Aims: The objective of this study was to compare the frequency of herpes simplex virus type 1 (HSV-1), Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) in subgingival plaque, saliva and peripheral blood of HIV-positive and-negative patients with periodontal disease. Materials and Methods: Fifty HIV-positive subjects (23 with gingivitis, 27 with periodontitis) and 50 healthy HIV-negative patients with chronic periodontitis were included in the study. Parameters of probing depth (PD), clinical attachment level (CAL), gingival index and plaque index were recorded. The samples were processed for viral identification by the nested polymerase chain reaction technique. Results: HCMV was the most prevalent virus in HIV-positive (82%) and-negative patients (84%), and the detection in the three samples was similar (p > 0.05). HSV-1 was the least prevalent virus in both groups, being detected in similar frequencies in oral sites and in peripheral blood. EBV-1 was found more frequently in saliva and subgingival plaque of HIV-positive patients than in HIV-negative patients (p <= 0.05). Conclusions: EBV-1 was more frequently recovered in oral sites of HIV-positive patients than in HIV-negative patients.