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Strong Positivity (strong + positivity)
Selected AbstractsChanges in the expression of P-cadherin in the normal, cryptorchid and busulphan-treated rat testisINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 5 2007K. Pospechova Summary Adhesion between Sertoli cells and germ cells is important for spermatogenesis. Cadherins are Ca2+ -dependent transmembrane proteins that mediate cell,cell adhesion. The aim of this study was to compare the expression of P-cadherin in unilaterally cryptorchid and busulphan-treated rat testes using immunohistochemistry. The pattern of expression of P-cadherin in the seminiferous epithelium changed with the stage of the seminiferous epithelium. The membranes of round spermatids and membranes and cytoplasm of spermatocytes were strongly positive. Our experiments revealed that busulphan treatment (2 doses , 10 mg/kg of body weight , 21 days apart) and cryptorchism led to destructive changes in the structure of seminiferous tubules, together with the decrease in P-cadherin expression. The expression of P-cadherin disappeared in the spermatids segregated from the epithelium while segregated spermatocytes remained still positive for P-cadherin during the 3- to 11-day cryptorchid period. In busulphan-treated animals, the expression of P-cadherin was dependent on the presence or absence of the spermatocytes and spermatids in the tubules. Strong positivity for P-cadherin was observed in the spermatocytes that re-appeared in the regenerating seminiferous epithelium. We suggest that P-cadherin participates in the architecture of adherens junctions in testis, plays an important role in maintaining normal spermatogenesis and that cryptorchism and busulphan treatment lead to adherens junction disintegration. [source] The diagnostic utility of D2-40 for malignant mesothelioma versus pulmonary carcinoma with pleural involvementDIAGNOSTIC CYTOPATHOLOGY, Issue 12 2006Ph.D., Reda S. Saad M.D. Abstract Differentiating malignant mesothelioma (MM) from pulmonary carcinoma in pleural fluid cytology can be challenging. Recent studies have suggested that D2-40, a novel lymphatic marker, may be a useful marker for mesothelial differentiation in surgical specimens. However, there are no available data regarding its utility in effusion cytology specimens. We investigated the utility of D2-40 in pleural fluid cytology in differentiating MM from pulmonary carcinomas. Twenty cases of pleural effusion smears of surgically confirmed MM with their corresponding cell blocks were retrieved from the database of the hospital computer system. We also included 10 cases of metastatic pulmonary adenocarcinoma (PA) and 10 cases metastatic pulmonary squamous cell carcinoma (PSCC) involving the pleural fluid. Cell blocks were formalin-fixed, paraffin embedded, and immunostained for TTF1, p63, calretinin, CK5/6, WT-1, and D2-40. Cases were scored as negative (<5% positivity) or positive (>5% moderate/strong positivity). The positive rates for TTF1, p63, calretinin, CK5/6, WT-1, and D2-40 were as follows: MM (0/20), (0/20), (17/20), (18/20), (19/20), (17/20), for PA (8/10), (0/10), (3/10), (0/10), (0/10), (0/10), and for PSCC (1/10), (10/10), (6/10), (10/10), (0/15), (0/10). The staining pattern for D2-40 was characterized by thick membranous staining. Diffuse cytoplasmic staining by D2-40 was seen in 2 cases of pulmonary carcinoma, counted as negative. Our study showed that in differentiating MM from PA, CK5/6, WT-1, and D2-40 have high specificity and sensitivity for MM. Although calretinin is a sensitive IHC marker for MM, it is not specific since it stained 30% of PA. Conversely, to differentiate between MM and PSCC, p63 and WT-1 are the best available markers. We recommend a panel of CK5/6, p63, D2-40, and WT-1 to differentiate MM from pulmonary carcinomas in effusion cytology specimens. Diagn. Cytopathol. 2006; 34:801,806. © 2006 Wiley-Liss, Inc. [source] Immunohistochemical expression of tumor antigens MAGE-A1, MAGE-A3/4, and NY-ESO-1 in cancerous and benign prostatic tissueTHE PROSTATE, Issue 1 2006Tvrtko Hudolin Abstract OBJECTIVE To investigate immunohistochemical expression of MAGE-A and NY-ESO-1/LAGE-1, cancer testis antigens in prostate tissues showing evidence of malignant transformation or benign hyperplasia. METHODS 112 prostate samples from patients undergoing surgery at the Urology Clinic at the Zagreb Clinical Hospital Center from 1995 to 2003 were investigated in this study. Of these, 92 carcinoma samples were obtained by radical prostatectomy, and 20 benign prostatic hyperplasia samples by transvesical prostatectomy. Three monoclonal antibodies were used for immunohistochemical staining: 77B for MAGE-A1, 57B for multi-MAGE-A and D8.38 for NY-ESO-1 expression. RESULTS Expression of MAGE-A1 was observed in 10.8% of carcinoma samples, whereas multi-MAGE-A and NY-ESO-1/LAGE-1 stained 85.9% and 84.8% of samples. Immunohistochemical staining was only detectable in the cytoplasm. A significant heterogeneity could be observed within a same tissue sample where areas with strong positivities coexisted with cancer testis antigens negative areas. Interestingly, a majority of 57B positive cases were also found to be D8.38 positive (correlation coefficient r,=,0.727 (P,<,0.01)). Cancer testis antigens expression was neither significantly correlated with PSA values nor with Gleason score. In benign prostatic hyperplasia tissues MAGE-A1 expression was detected in 5%, while 57B and D8.38 staining was observed in 15% samples, and in all cases percentages of positive cells were always <10%. CONCLUSION Our data underline the peculiar relevance of cancer testis antigens expression in prostate cancers, with potential implications regarding both diagnosis and therapy. © 2005 Wiley-Liss, Inc. [source] Phosphoinositide 3-kinase is not overexpressed in melanocytic lesionsJOURNAL OF CUTANEOUS PATHOLOGY, Issue 3 2007Rajendra S. Singh Background:, Although various studies have stressed the role of phosphatase and tensin homologue deleted on chromosome 10 (PTEN)-PI3K-AKT pathway in the progression of melanocytic lesions, little is known about the expression pattern of PI3K in these lesions. Objective:, To investigate the expression pattern of PI3K in benign and dysplastic nevi, primary melanomas, and metastatic melanomas and the role of PTEN and PI3K in melanocytic tumor progression. Methods:, Tissue microarrays were constructed using formalin-fixed, paraffin-embedded archival tissue blocks from 89 melanocytic lesions: 17 benign nevi, 18 dysplastic nevi, 23 primary melanomas, and 31 metastatic melanomas. Expression of PTEN and PI3K (p85 and p110 subunits) was evaluated immunohistochemically, and the number of cells and labeling intensity were assessed semiquantitatively. Results:, Both benign and dysplastic nevi showed strong cytoplasmic staining with PTEN, which was subsequently less in melanomas and completely lost in the metastatic lesions. Eleven of 17 (64%) benign nevi, seven of 10 (70%) dysplastic nevi, four of 23 (17%) primaries, and one of 31 (3%) visceral or lymph node metastasis showed strong positivity. Loss of PTEN expression from benign and dysplastic nevi to melanoma was statistically significant (p = 0.001). Although few cells showed reactivity for phosphoinositide 3-kinase (PI3 kinase)-p85 subunit, strong positivity was not detected in the cytoplasm of benign, malignant, or metastatic lesions, except for a single visceral metastasis. Three of 13 (23%) nevi showed positivity for the p110 subunit. No positivity was observed in the dysplastic nevi. Two of 22 (9%) melanomas, one of 14 (7%) visceral metastasis, and three of 12 (25%) lymph node metastasis showed strong positivity. There was no statistical difference in PI3 kinase expression in benign and malignant melanocytic lesions (p = 0.2). Conclusion:, PI3K is not overexpressed in melanocytic lesions. [source] Metastatic Basal Cell Carcinoma with Neuroendocrine Differentiation or Merkel Cell Carcinoma?JOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005A. Andea We present here a case of basal cell carcinoma (BCC) with neuroendocrine features that has transformed into a high-grade neuroendocrine carcinoma with various morphologic features of Merkel cell carcinoma (MCC). A 54-year-old white female was treated for a BCC of the right thigh. Pathologic examination revealed an otherwise classical BCC that demonstrated granular positivity for chromogranin. Six years later the patient developed a right inguinal lymphadenopathy diagnosed as metastatic BCC with squamous changes. The metastatic BCC showed partial peripheral palisading and a trabecular pattern. Two years later the patient underwent a right nephrectomy due to obstruction of the right ureter by metastatic BCC. After another four years the patient came back with extensive involvement of the appendiceal wall and right ovary by a diffusely infiltrating metastatic basaloid and trabecular carcinoma. This time the tumor had many histologic features of MCC and showed strong positivity for chromogranin and also for CK20 and NSE. Electron microscopy revealed neurosecretory granules. This case is an example of a chromogranin positive basal cell carcinoma of the skin, which transformed during multiple recurrences into a high grade neuroendocrine carcinoma with features of Merkel cell tumor, demonstrating the potential for cross differentiation among skin tumors. [source] Perineurioma of the mandibular dental nerve: a case report and review of the literatureORAL SURGERY, Issue 2 2009E.F. Vencio Abstract Perineurioma is an uncommon benign tumour of the nerve sheath composed exclusively of well-differentiated perineurial cells. It usually affects the limbs or trunk; intraoral lesions are uncommon. A rare case of perineurioma is described involving the mandibular dental nerve in a 59-year-old female, microscopically characterised by a combined pattern of intraneural and soft tissue perineurioma. The patient was referred for treatment of a lesion in the mandible. Panoramic radiography revealed a well-delimited osteolytic lesion with radiopaque halo in an edentulous region of the left mandible. Occlusal view showed no expansion of cortical bone. A surgical procedure for incisional biopsy disclosed a connection between the tumour and the alveolar inferior nerve. Grossly, an enlargement of the affected nerve was described. Microscopic examination showed tumour cells arranged in pseudo-onion bulb structures, with scattered collagen bundles, and areas with a whorled (storiform) arrangement. Many concentric whorls of spindle cells exhibiting thin, elongated eosinophic processes were seen. Immunohistochemical study exhibited strong positivity for epithelial membrane antigen. We report a rare case of perineurioma affecting the mandibular dental nerve showing both intraneural and soft tissue microscopic patterns and discuss morphological aspects for differential diagnosis. [source] | ||||||||||