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 São 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.

EBV detection in HIV-related oral plasmablastic lymphoma.

OBJECTIVES: Plasmablastic lymphoma (PBL) of the oral cavity is an aggressive neoplasm derived from B cell, considered to be the second more common among human immunodeficiency virus (HIV)-associated malignancies. As Epstein-Barr virus (EBV) infection has been associated with this neoplasm, the aim of the present study was to assess the presence of EBV in 11 cases of oral HIV-related PBL and investigate the controversial issue of the presence of Human herpesvirus-8 (HHV-8) in these tumors. METHODS: DNA was extracted from nine cases of HIV-associated oral lymphomas, diagnosed as PBL, and genomic material was amplified by polymerase chain reaction to verify the presence of EBV. In situ hybridization (ISH) for EBV was performed in five cases. Immunohistochemical analysis was conducted to confirm previous diagnosis and verify HHV-8 infection. RESULTS: The 11 cases had diagnosis confirmed by immunohistochemical analysis. Only nine cases presented an adequate amount of DNA for analysis, and EBV was detected in seven of them. The five cases tested for EBV viral infection by ISH showed positive signals. All 11 cases were negative for HHV-8. CONCLUSION: The presence of EBV in all cases studied favors a direct role of this virus in the development of HIV-related PBL, and this finding could be considered when dealing with HIV patients.

Polymorphous low grade adenocarcinoma presenting an uncommon radiographic aspect.

The aim of this study was to present clinical, histological and immunohistochemical aspects of a polymorphous low grade adenocarcinoma occurring in the mandible. A radiolucent tumour, located in the right mandible, was removed from a 40-year-old woman. Radiographic and CT exams revealed that the lesion expanded bucco-lingual cortical plates and presented an irregular scalloping of the bone. The surrounding lining mucosa was intact. The patient underwent total surgical removal of the lesion with an intraoperative biopsy. Histological diagnosis was polymorphous low-grade adenocarcinoma confirmed by immunohistochemical study. One-year follow up was uneventful. The accurate diagnosis of lesions presenting unusual clinical aspects, as the one presented here, is critical for correctly handling treatment.

Cytokeratins in epithelia of odontogenic neoplasms.

Neoplasms and tumours related to the odontogenic apparatus may be composed only of epithelial tissue or epithelial tissue associated with odontogenic ectomesenchyme. The immunohistochemical detection of different cytokeratins (CKs) polypeptides and vimentin has made it easier to explain the histogenesis of many epithelial diseases. The present study aimed to describe the immunohistochemical expression of cytokeratins 7, 8, 10, 13, 14, 18, 19 and vimentin in the epithelial components of the dental germ and of five types of odontogenic tumours. The results were compared and histogenesis discussed. All cells of the dental germ were positive for CK14, except for the preameloblasts and secreting ameloblasts, in which CK14 was gradually replaced by CK19. CK7 was especially expressed in the cells of the Hertwig root sheath and the stellate reticulum. The dental lamina was the only structure to express CK13. The reduced epithelium of the enamel organ contained CK14 and occasionally CK13. Cells similar to the stellate reticulum, present in the ameloblastoma and in the ameloblastic fibroma, were positive for CK13, which indicates a nature other than that of the stellate reticulum of the normal dental germ. The expression of CK14 and the ultrastructural aspects of the adenomatoid odontogenic tumour probably indicated its origin in the reduced dental epithelium. Calcifying odontogenic epithelial tumour is thought to be composed of primordial cells due to the expression of vimentin. Odontomas exhibited an immunohistochemical profile similar to that of the dental germ. In conclusion, the typical IF of odontogenic epithelium was CK14, while CK8, 10 and 18 were absent. Cytokeratins 13 and 19 labelled squamous differentiation or epithelial cells near the surface epithelium, and CK7 had variable expression.

Clinicopathologic features of 54 cases of paradental cyst.

OBJECTIVE: The aim of the study was to evaluate the clinicopathologic features of 54 paradental cysts. METHOD AND MATERIALS: The cases were retrieved from the files of the Department of Oral Pathology of the University of São Paulo, in Brazil. Only case files that included complete data, radiographs, and clinical history were used for the study. RESULTS: Most of the cysts were adjacent to a partially erupted mandibular third molar; only two cysts were adjacent to mandibular second molars, and one cyst was adjacent to a first molar. Women were affected more often than were men (33:21), and most of the patients were in their second or third decades. In most cases, the affected tooth had a history of one or more episodes of pericoronitis. Histologically, these cysts presented the typical features of an inflammatory cyst, having a lining epithelium, which apparently resulted from a union between reduced enamel epithelium and oral epithelium. CONCLUSION: Development of the paradental cyst could be avoided if episodes of pericoronitis were properly treated, because the cyst is usually related to pericoronitis.

Oral exfoliative cytology in the diagnosis of paracoccidioidomycosis.

OBJECTIVE: To assess the efficacy of conventional oral exfoliative cytology as a diagnostic tool in paracoccidioidomycosis. STUDY DESIGN: Cytologic smears and incisional biopsies were obtained from 10 patients with a clinical suspicion and oral manifestations of paracoccidioidomycosis. Cytologic smears and sections of the incisional biopsy underwent methenamine silver staining for fungi according to the Gomori-Grocott method. The dry glass slides were examined at 400 or 1,000 x magnification, and the presence and shape of yeasts of Paracoccidioides brasiliensis were investigated. RESULTS: Yeasts of the fungus P brasiliensis were clearly identified in cytologic smears and sections from incisional biopsies in all cases analyzed (100.0%). CONCLUSION: Cytology of oral samples proved an effective diagnostic method for the detection of paracoccidioidomycosis in humans.

Immunohistochemical aspects of basal cell adenoma and canalicular adenoma of salivary glands.

Basal cell adenoma is a benign epithelial neoplasm with a uniform histologic appearance dominated by basaloid cells. Those cells may be distributed in various arrangements as solid, trabecular, tubular and membranous. Canalicular adenoma is also a benign neoplasm composed by columnar cells arranged in branching and interconnecting cords of single or double cell thick rows. There is some disagreement among investigators about whether canalicular adenoma should be included within the basal cell adenoma histologic spectrum. In the present study we compared the expression of cytokeratins (CK), vimentin and muscle-specific actin, utilizing immunohistochemical technique, in three cases diagnosed as basal cell adenomas predominantly of the solid type, and three cases of canalicular adenomas. The results obtained showed a distinct immunoprofile for both neoplasms. Solid areas of basal cell adenomas did not stain for any of the tested antibodies; only when there was tubular differentiation, those structures expressed CKs 7, 8, 14, and 19 in luminal cells and vimentin in non-luminal cells. On the other hand, canalicular adenomas strongly expressed CKs 7 and 13. The panel of antibodies utilized supports the separation of the two entities.

Traumatic bone cyst: report of two cases and review of the literature.

Traumatic bone cysts usually are found in young individuals and most frequently have the radiographic appearance of well-circumscribed radiolucent lesions with a tendency to scallop between the roots of the teeth. Two well-documented cases of traumatic bone cysts are presented in which some differences related to their radiographic features were observed. The possible explanations for these differences are discussed and a brief review of the literature regarding the main characteristics of traumatic bone cyst lesions also is provided.

Application of immunohistochemistry to the diagnosis of salivary gland tumors.

A panel of antibodies composed of the cytokeratins (CKs), vimentin, and actin was applied to 114 minor salivary gland tumors to evaluate its diagnostic value. The results revealed that luminal cells of intercalated duct-like structures, such as those seen in pleomorphic adenoma, basal cell adenoma, adenoid cystic carcinoma, and epithelial-myoepithelial carcinoma, expressed CKs 7, 8, 14, and 19. The outer cells of these structures exhibited vimentin or vimentin plus muscle-specific actin, but rarely CK14, which is seen particularly in pleomorphic adenoma, in the tubular type of basal cell adenoma, and seldom in the tubular type of adenoid cystic carcinoma. Modified myoepithelial cells of pleomorphic adenoma and myoepithelioma exhibited a variable immunoprofile. CKs 7 and 8 were also observed in acinar cell adenocarcinoma and polymorphous low-grade adenocarcinoma with vimentin in the latter. CK13 was expressed only by canalicular adenoma and mucoepidermoid carcinoma cells. This study showed that the panel of antibodies employed is effective in distinguishing among salivary gland tumors.

Basal cell adenocarcinoma of the palate with squamous metaplasia.

Basal cell adenocarcinoma is a rare salivary gland tumour, especially in minor glands. The clinical, histological, and immunohistochemical features of a case involving the palate are described. Formalin fixed, paraffin embedded sections of the tumour were examined in haematoxylin and eosin (H&E) sections and also using immunostaining for cytokeratins 7, 8, 13, 14, 18, 19, vimentin, muscle specific actin (HHF35), and laminin. H&E sections showed that the tumour was composed mainly of basaloid cells and a striking feature was the presence of squamous metaplasia. Neural invasion was also conspicuous. Immunohistochemical reactions indicated that cytokeratin 14 was expressed by all tumour cells and vimentin by all cells except those in the areas of squamous metaplasia. The remaining cytokeratins and actin were present in some of the tumour cells, while laminin showed discreet positivity around cell arrangements. The foci of squamous metaplasia and the immunohistochemical findings are helpful in distinguishing basal cell adenocarcinoma from other salivary gland tumours which show basaloid cells.

Study of minor salivary gland mucoepidermoid carcinoma differentiation based on immunohistochemical expression of cytokeratins, vimentin and muscle-specific actin.

The expression of cytokeratins (CKs) 7,8,10,13,14,18,19, vimentin and muscle-specific actin (MSA) was investigated in 17 mucoepidermoid carcinomas (MEC) by the streptavidin-biotin technique. The results revealed that CKs 7, 8 and 18 were positive for intermediate, luminal columnar and mucous cells. For epidermoid cells, the expression was heterogeneous and discrete. The reaction with CK19 was similar to that seen for the above CKs, except for the fact that mucous cells were negative. CK 14 was preferentially expressed in the intermediate cells localised in basal, parabasal and epidermoid cells. CK13 was localised in intermediate, epidermoid and luminal columnar cells. In stratified epithelium, CK13 was expressed in intermediate cells and negative in basal cells. These findings were more expressive in cystic areas of the tumours. CK10 was negative for all the cases studied. MSA was positive only in stromal elements, and only two cases of CME were heterogeneously positive for vimentin. The result obtained showed that the immunoprofile of MEC, for the studied antigens, is similar to that exhibited by the excretory duct of normal salivary glands.

Immunohistochemical study of acinic cell carcinoma of minor salivary gland.

Acinic cell carcinoma (ACC) is a rare salivary gland tumour, making up 4% of all minor salivary gland tumors. Typically, it is composed of acinic cells although transitional and duct-like cells are also identified. In the present study, a panel of antibodies was applied to eight minor salivary gland ACCs. Antibodies tested were: cytokeratins 7, 8, 13, 14, 18, 19, vimentin and actin (HHF35). Immunohistochemical staining revealed that cytokeratin 8, among the tested antibodies, was the more specific to neoplastic cells with a pattern of distribution quite variable and peculiar. This staining may be useful in the recognition of neoplastic acinic cells.

Glandular odontogenic cyst: report of a case with cytokeratin expression.

The glandular odontogenic cyst is a rare lesion that was recognized as a distinct entity in the latest WHO typing of odontogenic tumors. We report a glandular odontogenic cyst that recurred after surgical removal from the anterior mandible of a 54-year-old white man. Immunohistochemical study showed that the cystic epithelium reacted positively to antibodies directed against cytokeratins (CKs) 7, 13, 14, and 19 and negatively to CKs 8 and 18.

Expression of different keratins in salivary gland tumours.

Twenty-four salivary gland tumours (six pleomorphic adenomas, two myoepitheliomas, five basal cell adenomas, six adenoid cystic carcinomas and five polymorphous low grade adenocarcinomas) were investigated by an immunocytochemical technique using monoclonal antibodies against cytokeratins (CKs) 7, 8, 10, 13, 14, 18 and 19. The luminal cells of ductal structures of the tumours reacted with all the CKs studied except for CK 13 and CK 10 and sometimes CK 14, showing an immunoprofile comparable to that of the intercalated segment of a normal salivary gland. The outer cells of the ducts rarely stained with CK 14, confirming that full differentiation of the myoepithelial cells is seldom achieved in tumours. Considerations were made regarding the intriguing expression of CK 14, the heterogeneous expression of CKs in the modified myoepithelial cells and the immunoprofile of the polymorphous low-grade adenocarcinoma.

Minor salivary gland tumours. A retrospective study of 164 cases in a Brazilian population.

One hundred and sixty-four cases of intraoral salivary gland tumours retrieved from the files of the Surgical Oral Pathology laboratory of the University of São Paulo (Brazil), between 1970 and 1993, were studied. Of these, 164 tumours, 62% were classified as benign and 38% malignant. The palate was the main site of occurrence of the tumours followed by the buccal mucosa and upper lip. There was a slight predominance for female patients, with a female to male ratio of 1.3:1. The mean age for benign tumours was 39.9 years (40.8 for females, and 39.7 for males). For malignant tumours the mean age was 43.5 years (42.6 for females and 44.7 for males). Pleomorphic adenoma was the most common of the benign tumours, whereas mucoepidermoid carcinoma and adenoid cystic carcinoma were the most common malignant tumours. In general, benign tumours presented as an asymptomatic nodule. On the other hand, pain, ulceration and radiographic changes were more frequently associated with malignant lesions.

Hemophilic pseudotumor of the jaws: report of two cases.

Hemophilic pseudotumor of bone is a rare condition that occurs in patients with hemophilia. To date only 10 cases have been reported in the mandible, and none has been reported in the maxilla. The clinical, radiographic, and histologic features and treatment approaches of two cases of hemophilic pseudotumor occurring in the jaws are presented. One of them is probably the first one reported in the maxilla. Both patients had a history of trauma to the area.

Inverted ductal papilloma of minor salivary gland origin: morphological aspects and cytokeratin expression.

Ultrastructural features and cytokeratin expression of inverted ductal papillomas of minor salivary gland origin were studied. Under the electron microscope, an increased number of desmosomes and mucus-like granules in some cells were the most striking features. Immunohistochemical study revealed that tumor cells displayed strongly positive reactions with cytokeratins 13 and 14, and less strong reactions with cytokeratins 7, 8, 18 and 5D3. These results support the hypothesis that an inverted ductal papilloma can be derived from the proximal portion of a salivary gland excretory duct.