Search results for "CYTOKERATIN"
showing 10 items of 92 documents
Special Program of Differentiation Expressed in Keratinocytes of Human Haarscheiben: An Analysis of Individual Cytokeratin Polypeptides
1993
Human haarscheiben, epidermal Merkel cell-rich sensory organs of hairy skin, were studied for the expression of various cytokeratin (CK) polypeptides and other epithelial and neuronal differentiation markers by applying immunoperoxidase and immunofluorescence microscopy to frozen sections and by two-dimensional gel electrophoresis. The basal clusters of Merkel cells were specifically detected by antibodies against CK 20. Haarscheiben keratinocytes were unique mainly by the prominent expression of CK 17 in the lower and middle layers. Further differences as compared to keratinocytes of usual epidermis included the enlargement of the basal compartment, characterized by the expression of CK 5 …
Cytokeratin expression patterns in low-grade papillary urothelial neoplasms of the urinary bladder.
2003
BACKGROUND The differential expression patterns of cytokeratin 20 (CK20) and 34βE12 antigen in low-grade papillary urothelial tumors of the bladder are discussed. METHODS A retrospective study of 120 patients with low-grade papillary bladder tumors (45 neoplasms of low malignant potential and 75 low-grade WHO G1 carcinomas) was performed. All tumors were graded in accordance with the 1998 World Health Organization/International Society of Urological Pathology (WHO/ISUP) and 1999 WHO classifications. The mean follow-up was 76.6 months (range, 36–168 mos), considering for prognostic purposes the time to first recurrence, or relapse-free interval (RFI), and the total number of recurrent patien…
Soft tissue Ewing's sarcoma. Characterization in established cultures and xenografts with evidence of a neuroectodermic phenotype.
1990
This study characterizes the histogenesis of soft tissue Ewing’s sarcoma (StEs) based upon an analysis of three tumors. Long-term cultured cell lines and nude mice xenografts were established from original neoplasms or from their metastases. Histologically they revealed a small round cell pattern without signs of differentiation. Several ultrastructural features of neural type were found; the same were also seen on culture cell lines. Moreover, immunohistochemical study for neural markers revealed the presence of HNK-1, NSE, LIRC-LON 36, S-100 protein, glial fibrillary acidic protein, neurofilaments (70 kilodaltons), and chromogranin; some of these markers were present only in the transplan…
Basaloid squamous cell carcinoma of the esophagus: diagnosis and prognosis.
1997
BACKGROUND. Basaloid squamous cell carcinoma (BSCC) is a recently recognized, poorly differentiated variant of squamous cell carcinoma (SCC), which is located predominantly in the upper aerodigestive tract. METHODS. In this study, clinical and pathologic parameters of 17 BSCCs and 133 typical SCCs of the esophagus that underwent potentially curative resection (no distant metastases, no residual tumor) were compared. In addition, light microscopic, electron microscopic, and immunohistochemical features of BSCC were investigated, to determine whether this type of carcinoma could be differentiated from other poorly differentiated carcinomas of the esophagus. RESULTS. Light microscopic study sh…
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…
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…
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 …
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…