Search results for "keratin"
showing 10 items of 303 documents
Beta-catenin and surviving expression in keratocystic odontogenic tumor (KCOT). A comparative immunohistochemical study in primary, recurrent and nev…
2013
Aim: To determine the epithelial expression of ß-catenin and survivin in sporadic (primary, and recurrent) and nevoid basal cell carcinoma syndrome (NBCCS) keratocystic odontogenic tumour (KCOT) in order to assess activation of the ß-catenin pathway and evidence of apoptotic inhibition, processes that may contribute to the known differences in their biological behaviour. Materials and Methods: Sections from 40 cases of KCOT (19 sporadic/primary; 9 sporadic/recurrent and 12 NBCCS-associated) were immunohistochemically stained for ß-catenin and survivin. The extent and intensity of immunoreactivity within the lining epithelium was assessed, using semi-quantitative scales, independently by two…
Translocation (X;18) in a Biphasic Synovial Sarcoma with Morphologic Features of Neural Differentiation
1998
The authors report a recurred neoplasm showing distinctive histologic, immunophenotypic, and ultrastructural features characteristic of biphasic synovial sarcoma with neural differentiation. The features include areas with a growth pattern of densely packed spindle cells in irregularly intersecting, broad fascicles, diffuse vimentin and HBA 71 immunoreactivity, expression of S-100 protein, and other neural markers. Moreover, areas with glandular structures and cellular expression of cytokeratin and epithelial membrane antigen were noted. Additionally, areas of neural-like growth pattern were positive for neuron-specific enolase, HNK-1, and protein gene product 9.5. Furthermore, cytogenetic …
Changes in cytokeratin expression accompany squamous metaplasia of the human respiratory epithelium.
1992
To determine the characteristics of metaplastic changes of the nasal respiratory epithelium, the distribution of individual cytokeratins (CKs) was studied immunohistochemically and by two-dimensional gel electrophoresis. The authors define four types of changes of the normal pseudostratified columnar epithelium: (1) transitional pseudostratified epithelium (first unusual CK.: no. 13); (2) stratified columnar epithelium (increased expression of CKs 4 and 13; CKs 7, 8, 18 and 19 reduced); (3) stratified squamous epithelium, non-keratinized (appearance of CK 16); and (4) stratified squamous epithelium, keratinized (expression of CKs 1 and 10, variable CK5 and 14 patterns in basal cells). These…
Chromophobe cell renal carcinoma and its variants--a report on 32 cases.
1988
This paper reports on 32 chromophobe cell renal carcinomas observed in 697 renal cell cancers (RCC) of adults (peak in the sixth decade of life). The chromophobe cell-type differs from other types of RCC macroscopically, the cut-surface being predominantly of grey-beige colour. Histologically, there are two variants: one is the typical (light) variant (n = 22) and the other is eosinophilic (n = 10). Both variants have in common (a) reaction of the cytoplasm with Hale's acid iron colloid; (b) electron microscopic detection of cytoplasmic microvesicles (150-300 nm), frequently with 'inner vesicles', and (c) low glycogen content in comparison with the clear cell carcinoma. Immunocytochemical i…
Bipolar (neural and myoblastic) phenotype in cell lines derived from human germ cell tumours of testis.
1997
Non-seminomatous germ cell tumours of the testis (NSGCT) form a heterogeneous group of neoplasms. Cell lines derived from NSGCT may provide useful data concerning the biology of neoplasic precursor germ cells, differentiation of tumour stem cells and the relationship between various tissue components of these tumours. Four NSGCT were studied, two mixed tumours composed of teratocarcinoma, yolk sac and trophoblastic elements, and two malignant teratomas with a massive neuroectodermal component, equivalent to primary neuroectodermal tumours (PNET) of the testis. The explanted tumours gave rise to various cell populations, including epitheloid cells, flattened large cells, spindle cells and te…
Stimulation of T cells by autologous mononuclear leukocytes and epidermal cells in psoriasis.
1986
Based on reports suggesting aberrant cell-mediated immunity and altered infiltration of immunocompetent cells into the skin in psoriasis, we studied the stimulation of T cells by autologous non-T mononuclear leukocytes (autologous mixed lymphocyte reaction, AMLR) and by epidermal cells isolated from lesional and clinically uninvolved skin in psoriasis (autologous mixed epidermal cell lymphocyte reaction, AMECLR). Age- and sex-matched individuals served as controls. We found that the AMLR in psoriasis (n = 11) was similar to that in healthy controls (n = 16); furthermore, cell proliferation was alike in the presence of either 5% AB-serum or autologous serum. By contrast, while the AMECLR in …
Behavior of Epithelial Differentiation Antigens (Carcinoembryonic Antigen, Epithelial Membrane Antigen, Keratin and Cytokeratin) in Transitional Cell…
1992
Results of an immunohistochemical study in normal urothelium and transitional cell carcinomas of the bladder are presented. Paraffin-embedded material was confronted with immunoantisera against carcinoembryonic antigen (CEA), keratin (K), cytokeratin (CK) and epithelial membrane antigen (EMA). Immunohistochemical findings confirm the changes in reactivity of dysplastic urothelium and carcinoma in situ for CEA, CK and EMA, in comparison with normal urothelium. Statistically significant differences were also found, depending upon tumor stage, in staining of transitional cell carcinomas for K and CK. Expression of CK correlated with the tumor differentiation grade: normal urothelium and well-d…
Comparative cytokeratin analysis of sweat gland ducts and eccrine poromas.
1991
Human eccrine sweat gland ducts and benign and malignant eccrine poromas were studied for the expression of various cytokeratins (CK) and vimentin by applying immunoperoxidase and immunofluorescence microscopy to frozen or paraffin-embedded sections, and using two-dimensional gel electrophoresis and immunoblotting. In acrosyringia and dermal eccrine ducts, the luminal cells exhibited intense staining for CKs 1/10/11 and 19. The periluminal cell layers of acrosyringia contained CKs 1/10/11, while CK 5 was absent. In contrast, the basal cell layer of dermal ducts was only positive with the antibody against CK 5, i. e. a pattern resembling that seen in epidermal basal cells. CK 9 was detected …
Differential expression of Cyclin D1 in keratin-producing odontogenic cysts
2015
Objetives: The aim of the present study was to analyze the expression levels of Cyclin D1 (CCD1), a nuclear protein that plays a crucial role in cell cycle progression, in a series of keratin-producing odontogenic cysts. Study Design: A total of 58 keratin-producing odontogenic cysts, diagnosed over ten years and classified according to the WHO 2005 criteria, were immunohistochemically analyzed in terms of CCD1 expression, which was quantified in the basal, suprabasal and intermediate/superficial epithelial compartments. The extent of immunostaining was measured as a proportion of total epithelial thickness. Quantified immunohistochemical data were correlated with clinicopathological featur…
Intermediate filaments and desmosomal plaque proteins in testicular seminomas and non-seminomatous germ cell tumours as revealed by immunohistochemis…
1987
Seminomas and non-seminomatous testicular germ cell tumours were studied for the presence of cytokeratin and vimentin filaments and desmosomes using immunohistochemical methods. In the majority of the classical seminomas and in seminomatous areas of mixed tumours most tumour cells appeared to lack cytokeratin filaments. Some seminomas contained a focally variable proportion of cells exhibiting cytokeratin-positive structures while other cases contained only few seminoma cells with a well developed fibrillar cytokeratin network. Gel electrophoresis of cytoskeletal proteins from microdissected regions revealed cytokeratin polypeptides nos. 8 and 18 typical of simple epithelia. In one seminoma…