A comparative immunohistochemical study of cytokeratin and vimentin expression in middle ear mucosa and cholesteatoma, and in epidermis

Abstract

Cytokeratin expression was studied in human middle ear cholesteatoma lesions, using a variety of immunohistological techniques and a wide range of polyclonal antisera and monoclonal antibodies against cytokeratin (CK) subgroups or individual CK polypeptides. The expression of the other cytoskeletal proteins, vimentin and desmin, was also investigated. Middle ear mucosa and epidermal tissues were used as reference tissues. Our investigations also included epithelial structures present in the cholesteatoma perimatrix and in dermal tissues. The results indicate that, compared with epidermal tissues, the expression profile of CKs in cholesteatoma matrix is representative of a hyperproliferative disease. Evaluating the presence of a marker of terminal keratinization - the 56.5 kD acidic CK n degrees 10 - we found supportive evidence of a pronounced retardation of its expression, which did not parallel histological differentiation. In epidermal tissues, the first prickle cell layers are CK10 positive whereas in many cholesteatomas this finding was observed near the stratum granulosum only. Probing the early stages of keratinization - the 58 kD basic CK n degrees 5 and the 50 kD acidic CK n degrees 14 - we regularly observed an extended staining area in the cholesteatoma matrix. In epidermal reference tissues, only the basal and nearest suprabasal layers were convincingly labeled. As a rule, non-epidermal CKs did not belong to the cholesteatoma CK set. However, exceptions to that rule were noticed as a focal or more extended expression of one or more non-epidermal CKs in about half of the cases. Together with the extended CK5 topography, this is further evidence that CK expression is seriously affected by the diseased state. CK expression in the perimatrix is limited to mucous glands, either normal, atrophic or hyperplastic. CKs n degrees 4, 5, 7, 14, 18 and 19, also displayed by middle ear mucosa, were consistently observed. Where ductal arrangements were present, CK10 was also detected, in analogy with the CK10 registration in ductal portions of mucous glands in the external ear canal skin. The absence of CK8 in mucous glands of the perimatrix, however, strongly differentiates these structures from the mucous gland acini and ducti in the external ear canal, where CK8 is systematically expressed. Vimentin staining was restricted to dendritic cells of the matrix (Langerhans cells) and to perimatrix fibroblasts, blood cells and vascular endothelium. Coexpression of CK and vimentin was not observed.

Human‐papillomavirus DNA in cholesteatomas

“…Different mechanisms have been postulated for its pathogenesis (Palva, 1990). Several studies that have been conducted on the cytokeratin expression in these tumours support the migration theory (Van Blitterswijk and Grote, 1988;Broekaert et al, 1988;Chao and Huang, 1989).…”

“…from respiratory epithelium into squamous epithelium (Tumarkin, 1938). However, this mechanism finds no experimental support in cytokeratin studies, which show a connection between the tumour tissue, the tympanic membrane and the ear-canal epidermis (Van Blitterswijk and Grote, 1988;Broekaert et al, 1988;Chao and Huang, 1989). The erosion or destruction of the ossicles and the temporal bone is a common feature which, if untreated, may lead to hearing loss, facial paralysis, labyrinth fistula and, in severe cases, to the development of brain abscesses and meningitis.…”

Expression Patterns of Cytokeratins in Cholesteatomas: Evidence of Increased Migration and Proliferation

“…CK5 and CK14 are synthesized in the basal epithelial cells, and are used as markers of keratinizing squamous epithelium (1,2,3,18). The presence of this pair of CK was detected in human cholesteatoma tissue by using SDS-PAGE (6).…”

“…Each pair of acidic and basic CK is assembled into a 10-nm filament. The pattern of CK expression is affected only, if at all, by neoplasia (1) and some proliferative epidermal diseases including psoriasis, aural cholesteatoma, as well as other epithelial disorders (2)(3)(4)(5)(6)(7)(8)(9)(10).…”

Immunohistochemistry, A Valuable Tool in Detection of Cervical Lymph Node Micrometastases in Head and Neck Squamous Cell Carcinoma: A Prospective Study

“…CK expression in a certain type of epithelium has been found to depend on various factors, such as the stage of embryonal development [16], inflammation [17], and environmental influences such as vitamin A [18], growth condition [19] and (pre) malignant transformation [20].…”