cytokeratin


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Related to cytokeratin: cytokeratin 18, cytokeratin 20, cytokeratin 7

ker·a·tin

(ker'ă-tin),
Collective name for a group of proteins that form the intermediate filaments in epithelial cells. Keratins have a molecular weight between 40 kD and 68 kD and are separated one from another by electrophoresis and isoelectric focusing; thus separated, they are sequentially numbered from 1-20, and also subdivided into low, intermediate, and high molecular weight proteins. According to their isoelectric mobility they are either acidic or basic. In general, each acidic keratin protein has its basic equivalent with which it is paired to form the intermediate filaments; some keratin proteins, however, occur unpaired. Various epithelial cells contain different keratin proteins, in a tissue-specific manner. Antibodies to keratin proteins are widely used for histologic typing of tumors, and are especially useful for distinguishing carcinomas from sarcomas, lymphomas, and melanomas.
Synonym(s): ceratin, cytokeratin
[G. keras (kerat-), horn, + -in]

cytokeratin

A global term for the family of intermediate filament proteins of epithelial origin; the pattern of cytokeratins (CKs) expressed may help differentiate colorectal from lung carcinomas based on low and high molecular weight types.

ker·a·tin

(ker'ă-tin)
A scleroprotein or albuminoid present in hair and nails; it contains a relatively large amount of sulfur, is insoluble in gastric juice, and is sometimes used for coating tablets that are intended to be dissolved only in the intestine.
Synonym(s): cytokeratin.
[G. keras (kerat-), horn, + -in]

cytokeratin

(sīt″ŏ-ker′ăt-ĭn) [ cyto- + keratin],

CK.

Any of the intermediate-sized filament proteins found in epithelial cells. Antibodies against CKs are used to detect specific cell types. The detection of unique CKs helps in the immunohistochemical identification of the origin of specific cancers.
References in periodicals archive ?
Cytokeratin contents of basal cell carcinoma, epidermis overlying tumour, and associated stromal amyloidosis: an immunohistochemical study.
We used to think that cytokeratins were primarily structural proteins, but our study shows that these fragments of keratin also have microbe-fighting capabilities," said study lead author Connie Tam, an assistant research scientist in Fleiszig's lab.
A prospective study comparing touch imprint cytology, frozen section analysis, and rapid cytokeratin immunostain for intraoperative evaluation of axillary sentinel lymph nodes in breast cancer.
Within alveolar septa stained for both CYP1A1 and cytokeratin 8/18, the area of BNF-induced CYP1A1 expression localized to cells without the alveolar type II markers (cytokeratin 8/18) was significantly reduced (p [less than or equal to] 0.
Evaluation of napsin A, cytokeratin 5/6, p63, and thyroid transcription factor 1 in adenocarcinoma versus squamous cell carcinoma of lung.
The immunohistochemical markers CD99, Bcl-2, AE1/AE3, cytokeratin and EMA markers are normally positive in synovial sarcoma.
The HCC biomarkers cytokeratin 8 and plasminogen activator inhibitor 1 (PAI-1) were all significantly increased in arsenic-induced HCC, and also higher in arsenic-exposed tumor-surrounding tissues.
The choices for basal markers include both HMWCKs, such as 34[beta]E12 and cytokeratin 5/6, which stain the cytoplasm of basal cells, and p63, which stains the nuclei of basal cells.
Neoplastic cells were negative for actin, desmin, von Willebrand factor, and cytokeratin, while they were diffusely immunoreactive for vimentin (Fig 4).
Ampullary carcinoid cells express chromogranin in 92% of cases and neuron specific enolase, synaptophysin and cytokeratin in 100%; somatostatin is found in 58 to 67% of cases.
Uptake of cytokeratin 20 in the laryngeal and rectal specimens was similar.
In four cases, a differential diagnosis of adenocarcinomas of both lung and pancreas was obtained after cytokeratin (CK) 7 and CK 20 immunohistochemistry.