Zytokeratinexpression benigner und maligner epithelialer Schilddrüsentumoren

Abstract

Using 8 different monoclonal antibodies, immunohistology was performed on 36 follicular adenomas and on 28 follicular, 34 papillary, 27 medullary and 29 anaplastic carcinomas of the thyroid. The panel of antibodies was directed against broad-spectrum cytokeratins (pan-CK, antibody lu-5), against basic and acid high-molecular-weight CK of types #1, 5, 10 and 14, against basic (#5 and 6) and acid high-molecular-weight CK (#13) and against basic (#7 and #8) and acid low-molecular-weight CK (#19 and #20). With the exception of a large number of anaplastic carcinomas, nearly all other tumours exhibited strong immunoreactivity with antibodies against pan-CK, CK 8 and CK 19. CK 20 expression was exclusively shown for 2 medullary carcinomas. Reactivity for high-molecular-weight CK could only, each time focally, be demonstrated for 14 papillary and 2 follicular carcinomas and for 2 anaplastic carcinomas with partial squamous differentiation. Thirteen anaplastic carcinomas were not decorated by any of the CK antibodies applied. CK 7 staining exceeding the staining of individual cells was observed in 26 papillary cancers. In contrast, such a finding could only be obtained with each one follicular adenoma, medullary carcinoma and anaplastic carcinoma and with 5 follicular carcinomas. These results confirm earlier studies in that CK 20 expression among thyroid tumours is restricted to the neuroendocrine medullary carcinomas and that in a larger percentage of anaplastic thyroid carcinomas an epithelial phenotype can not be demonstrated even upon using broad-spectrum CK antibodies. New is the finding that there exist considerable differences between papillary carcinomas and all other non-papillary thyroid tumours regarding CK 7 expression. This result might be of differential diagnostic value for the distinction of follicular and papillary thyroid neoplasias which sometimes have an overlapping histological pattern.

Free-flow isoelectric focusing of proteins remaining in cell fragments following sonication of thyroid carcinoma cells

“…The results summarized in Table 1 Although the polypeptides of only eight exemplary bands were investigated, the results confirm that cytoskeletal proteins can be separated by FF-IEF [9]. In addition, they are consistent with earlier observations that cytokeratins 7 and 8 are markers of thyroid carcinoma cells, while cytokeratin 7 is especially expressed in papillary thyroid carcinomas [20,21], that cytokeratin 8 is often overexpressed in metastatic cells [22,23] and may be associated with cytokeratin 18, which together form a more stable complex for filament formation [24,25]. The results also revealed three proteins, which to our knowledge have never been seen in thyroid cells before.…”

Serum cytokeratin 19 fragments: a dedifferentiation marker in advanced thyroid cancer

“…Histological diagnosis was obtained in only one metastasis from a patient with multiple metastases and, consequently, no data are available on the relationship between serum and tissue Cyfra 21.1 expression. Anyway, increased serum Cyfra 21.1 levels were previously reported in patients with primary aggressive thyroid carcinomas despite low or absent CK19 immunostaining in corresponding tumor tissues (13,14,21). Previous studies in human lung and liver cancer cell lines showed that among CK19-producing cells, only those with caspase-3 (an enzyme involved in apoptosis phenomena) expression induced high Cyfra 21.1 levels in culture supernatants (22,23,24).…”

“…The cytokeratin 19 (CK19) is an acidic protein of 40 kDa that is part of the cytoskeleton of epithelial cells. Tissue CK19 is highly expressed in DTC, mainly those with papillary histotype (PTC) (13,14). The CK19 is specifically recognized by two MABs KS 19-1 and BM 19-21; CK19 soluble fragments (Cyfra 21.1) can be measured by employing these antibodies in a specific immunoradiometric 'sandwich' assay (15).…”

Increased PADI4 expression in blood and tissues of patients with malignant tumors

“…However, we detected PADI4 primarily in the cytoplasm of tumor cells in most malignant tissues as well as citrullinated cytokeratin in certain malignant tumors [3]. As keratins (notably K5, K7, K8/K18, K19, and K20) exhibit characteristic expression patterns in human tumors, and have great importance in immunohistochemical tumor diagnosis of carcinomas [6,28,29], it is thus possible that citrullination of histones, keratin and antithrombin are all involved in the tumorigenic process. Our proposed mechanism for PADI4 in tumorigenesis is shown in Figure 5.…”