Search results for "cytokeratin"
showing 10 items of 92 documents
Cytokeratin Analysis of Pilomatrixoma: Changes in Cytokeratin-Type Expression During Differentiation
1988
The various structural components of pilomatrixoma (calcifying epithelioma of Malherbe) were studied for the expression of hair-specific (trichocytic) cytokeratins as well as epithelial cytokeratins, using immunoperoxidase as well as epithelial cytokeratins, using immunoperoxidase and immunofluorescence microscopy of frozen sections as well as two-dimensional gel electrophoresis and immunoblotting. Trichocyte-type cytokeratins were detected in only a minor subpopulation of basophilic cells but more prominently in most “transitional” cells as well as in “shadow” cells. in contrast, antibodies against certain epithelial cytokeratins (including antibody KA1 against cytokeratins of stratified s…
Clinical and Immunohistochemical epithelial profile of non-healing chronic traumatic ulcers
2020
Background: Chronic wounds were previously related to cancer. Chronic Traumatic Ulcers (CTU) are lesions caused by chronic mechanical irritation (CMI) frequently diagnosed in Oral Medicine. Although these conditions may re-flect a benign nature, some authors have proposed its relationship with malignant transformation. Currently, there are scarce investigations that evaluate biomarkers within CTU. The aim of this study was to evaluate cell differentiation and proliferation biomarkers patterns of CTU and OSCC through recognized markers such as cytokeratin 19 and Ki67 and correlate it with clinical features of both groups of patients. Material and Methods: A Cross-sectional study of adult pat…
Mucoepidermoid mammary carcinoma. Immunohistochemical and biochemical analyses of intermediate filaments.
1989
The histological features of mucoepidermoid mammary carcinomas (MMCs) are presented, and criteria for distinguishing these tumours from squamous epithelial metaplasia in other mammary carcinomas are considered. Immunohistochemical and gel-electrophoretic analyses of the intermediate-filament proteins in one MMC case revealed a complex pattern of cytokeratin polypeptide expression. The simple-epithelium-type cytokeratins 7, 8, 18, and 19 were detected mainly in nonsquamous (including mucinous) cells, while the stratified-epithelium-type cytokeratins 5, 6, 14, 16, and 17 were present in squamous cells. However, in both the nonsquamous and squamous regions of the tumour, cytokeratins of the "r…
Characterization of subcolumnar reserve cells and other epithelia of human uterine cervix. Demonstration of diverse cytokeratin polypeptides in reser…
1987
We have analyzed the expression of cytokeratin polypeptides in subcolumnar reserve cells of the human uterine endocervical mucosa and the other epithelial cells using immunoperoxidase and immunofluorescence microscopy as well as by applying two-dimensional gel electrophoresis to microdissected cytoskeletal preparations. Endocervical columnar cells were uniformly positive for antibodies directed against the simple epithelium-type cytokeratins nos. 7, 8, 18, and 19, while a variable proportion of these cells was stained by an antibody against cytokeratin no. 4. Reserve cells were not only positive for cytokeratins nos. 8 (weakly and variably) and 19 but were also decorated by antibody KA 1, w…
Cytokeratin 20 Is a General Marker of Cutaneous Merkel Cells While Certain Neuronal Proteins Are Absent
1995
Merkel cells are difficult to identify in tissue sections. Previous studies have used cytokeratins (CK) 8, 18, and 19 as histologic markers of Merkel cells. However, these CKs are also expressed in some outer root sheath keratinocytes and some early fetal epidermal cells and thus are not truly specific of Merkel cells in general. Using selective antibodies against a newly described CK, number 20--originally found in intestinal epithelium and Merkel cell carcinomas--in comparison to a key protein of neuroendocrine cells, chromogranin A, we established CK 20 as a specific Merkel cell marker in skin of humans, pigs, and mice. CK 20 seems to be an even more general and sensitive Merkel cell mar…
Role of one-step nucleic acid amplification (OSNA) to detect sentinel lymph node low-volume metastasis in early-stage cervical cancer.
2019
IntroductionGrowing evidence in the literature supports the accuracy of sentinel lymph node (SLN) biopsy in early-stage cervical cancer. One-step nucleic acid amplification (OSNA) is a rapid assay able to detect cytokeratin 19-mRNA in SLNs, and it can be used for intra-operative detection of low-volume metastases. The aim of this study was to evaluate the rate of low-volume metastasis in SLNs detected by OSNA in patients with early-stage cervical cancer. Secondary aims were to define the sensitivity and the negative predictive value of SLN biopsy assessed with OSNA.MethodsAfter IRB approval, consecutive patients who underwent surgery for International Federation of Gynecology and Obstetrics…
Characterization of liver cytokeratin as a major target antigen of anti-SLA antibodies.
1990
Abstract Anti-SLA antibodies characterize a newly defined subgroup of patients with autoimmune chronic active hepatitis. The aim of the present study was the immunochemical characterization of the target antigen(s) of anti-SLA antibodies. Anti-SLA-positive sera were found to contain high titres of anti-cytokeratin antibodies. In immunoblotting analyses with 100 000 × g supernatants of human liver homogenates (S-100) these sera recognized various proteins with a molecular mass of 40–60 kDa. These proteins were also recognized by monoclonal anti-cytokeratin antibodies. Two-dimensional co-electrophoresis and immunoblotting analysis of S-100 and liver cytokeratins showed that anti-SLA antibodie…
Microcystic pseudoglandular plexiform cutaneous neurofibroma
2015
Glandular structures are well documented to appear in peripheral nerve sheath tumors. These epithelial elements are usually present in malignant peripheral nerve sheath tumors although a few cases of glandular benign peripheral nerve sheath tumors have also been described, most of them being schwannomas. A neurofibroma with glands is considered to be a rare type of divergent differentiation, but a neurofibroma containing gland-like or pseudoglandular structures have not, to our knowledge, been described. We report a 33-year-old patient with a well-demarcated dermal neoplasm, composed of neoplastic Schwann cells, perineurial-like cells and fibroblasts in a matrix with collagen fibers and myx…
The human gene encoding cytokeratin 20 and its expression during fetal development and in gastrointestinal carcinomas
1993
The differentiation of the predominant cell types of the mucosal epithelium of the mammalian gastrointestinal tract is characterized by increasing amounts of an intermediate-sized filament (IF) protein designated cytokeratin (CK) 20 which is a major cellular protein of mature enterocytes and goblet cells. Here we report the isolation of the human gene encoding CK 20, its complete nucleotide sequence and the amino acid sequence deduced therefrom that identifies this polypeptide (mol. wt. 48553) as a member of the type I-CK subfamily. Remarkable, however, is the comparably great sequence divergence of CK 20 from all other known type I-CKs, with only 58% identical amino acids in the conserved …
Different patterns of cytokeratin expression in the normal epithelia of the upper respiratory tract
1985
The distribution and type of cytokeratins present in the normal human epithelia of the nasopharynx, oropharynx, tongue, palatine tonsil, epiglottis, vocal cord, and laryngeal ventricle were studied using immunohistochemical techniques and by gel electrophoresis of cytoskeletal proteins microdissected from frozen tissues. Noncornifying stratified epithelia covering the oropharynx, tongue, surface of the palatine tonsil, pharyngeal surface of the epiglottis, and vocal cord were all found to contain cytokeratins nos. 4, 5, 6, 13, 14, and 15, together with minor amounts of cytokeratin no. 19, i.e., a pattern similar to that previously reported for esophageal epithelium. The immunohistochemical …