Markers cytokeratins

Figure 5.2 Comparison of immunohistochemical staining results among variable periods, 6 h to 30 days, of formalin-fixed, paraffin-embedded human breast cancer tissue (A-N), and cell line MCF-7 sections (O-Bl). All four markers, estrogen receptor (ER) (A-G), CK (cytokeratin cocktail, H-N), Her2/neu (O-U), and MIB-1 (V-Bl), showed comparable positive immunostaining results at +++ level after antigen retrieval. Original magnification x 200. Bar = 50 tm. Reproduced with permission from Shi et al., I Histochem. Cytochem. 2007 55 105-109. See color insert.

Keratins are alpha-type fibrous polypeptides with a diameter of 7 11 nm. They are important components of the cytoskeleton in almost all epithelial cells as well as in some nonepithelial cell types. Keratins are generally held to be the most ubiquitous markers of epithelial differentiation. So far, 20 distinct types numbered by Moll et al. (1982a, 1990, 1992) have been revealed. Keratins were earlier thought to be separable into hard and soft, or cytokeratins and other keratins, but these designations are now understood to be incorrect. In 2006, a new nomenclature (Schweizer et al. 2006) was adopted for describing keratins which takes this into account (Table 13.1). 

Demirkesen C, Hoede N, Moll R (1995) Epithelial markers and differentiation in adnexal neoplasms of the skin an immunohistochemical study including individual cytokeratins. JCutan Pathol 22(6) 518 535... 

Moch H, Kononen J, Kallioniemi OP, Sauter G (2001) Tissue microarrays what will they bring to molecular and anatomic pathology Adv Anat Pathol 8 14 20 Moll R (1998) Cytokeratins as markers of differentiation in the diagnosis of epithelial tumors. Subcell Biochem 31 205 262... 

Moll R, Lowe A, Laufer J, Franke WW (1992) Cytokeratin 20 in human carcinomas. A new histodiagnostic marker detected by monoclonal antibodies. Am J Pathol 140 427 447 Moll R, Divo M, Langbein L (2008) The human keratins biology and pathology. Histochem Cell Biol 129 705 733... 

Dithranol in combination with urea is widely used in psoriasis to improve the clinical efficacy, to minimize the dithranol concentration, to achieve the desired effect, to shorten the contact, to get a better hydration of the stratum corneum, and to decrease the proliferation rate of the keratinocytes. Gabard and Bieli showed an increased keratolytical effect of salicylic acid by adding 10% urea.54 Hagemann and Proksch55 showed in 10 patients with psoriasis under a 2-week treatment with a 10% urea ointment increased stratum corneum hydration, a small decrease in TEWL, a reduction in epidermal thickness (-29%), and a decreased epidermal proliferation (-51%). The altered expression of involucrin and cytokeratins as marker for epidermal proliferation was partially reversed.55... 

Efficacy markers allow monitoring of the efficacy of a given drug treatment [serum CYFRA 21-1 (cytokeratin-19 fragments) in breast cancer (Nakata et al., 2004)]. 

Buccheri G, Ferrigno D. Lung tumor markers of cytokeratin origin an overview. Lung Cancer 2001 34 S65-S69. 

Typical ES/PNET is nonreactive for chromogranin, cytokeratin, glial fibrillary protein, desmin, muscle-specific actin, myogenin, CD31, and However, in studies of tumors that were confirmed by molecular identification of the t(ll 22) translocation, immunoreactivity for cytokeratin has been present in 20% to 30% of ES/PNET cases.Nonetheless, in our experience, keratin has been relatively focally expressed in these tumors when present. NB84 (a marker developed for recognition of neuroblastoma) is also apparent in roughly 20% of ES/PNETs. 

S-100 protein is not diffuse in MCS. It is limited to the chondroblastic islands of that tumor and is lacking in the small cell component. All elements potentially label for CD57, and most cases are also reactive for NSE. Factor Xnia has been documented in MCS as well, but that marker is non-specific.Tumors of this type arising in the central nervous system are alleged to show cytokeratin and GFAP reactivity in 25% of cases,but we are dubious of that contention based on our experience. 

In our experience with ten cases, there has been no labeling for NSE, CD57, cytokeratin, chromo-granin, SlOO protein, EMA, vWF, CD31, UEAI, or carcinoembryonic antigen in ASPS. Melanocyte-specific markers are also absent in this neoplasm. ... 

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