The Distribution of Vimentin and Keratin in Epithelial and Nonepithelial Neoplasms: A Comprehensive Immunohistochemical Formalin- and Alcohol-Fixed Tumors

Abstract

Vimentin has been regarded as the intermediate filament characteristic of normal and neoplastic mesenchymal cells and keratins as typical of epithelial cells and the neoplasms derived from them. However, many epithelial cells in tissue culture or in effusion, as well as cells in some solid epithelial neoplasms such as renal, endometrial, ovarian, pulmonary, and thyroid adenocarcinomas, have been shown to coexpress vimentin and keratin. The recent availability of monoclonal antibodies that work reasonably well in paraffin-embedded tissue led us to carry out a comprehensive immunohistochemical study on formalin- and alcohol-fixed specimens of neoplasms in which we used monoclonal antibodies against vimentin. These results were compared with our previous study in which the same tumor tissues were investigated using antibodies against keratin. The antigenicity of vimentin was found to be preserved in all alcohol-fixed specimens and in 63% of formalin-fixed tissues. Vimentin was the sole intermediate filament present in virtually all sarcomas, meningiomas, schwannomas, and melanomas. In addition, variable percentages (10-57%) of carcinomas, neuroendocrine carcinomas, neuroblastomas, thymomas, and mesotheliomas were positive for vimentin, which, except in the neuroblastomas, was coexpressed with keratins. Among the adenocarcinomas, more than 50% of papillary carcinomas of the thyroid, as well as renal, endometrial, ovarian, and lung carcinomas, coexpressed keratins and vimentin. A distinctive paranuclear and basal localization of vimentin was observed in the cells of many of these tumors, in contrast to the predominantly apical distribution of the keratins. The authors conclude that coexpression of vimentin and keratin is more widespread than previously reported and that antibodies to vimentin, by themselves, are of limited value for the differentiation of epithelial from mesenchymal neoplasms.

Targeted Deletion of Prkar1a Reveals a Role for Protein Kinase A in Mesenchymal-to-Epithelial Transition

“…Vimentin itself is considered a marker for mesenchymal cells, and recent data indicate that it also has a functional role in promoting the mesenchymal phenotype and invasiveness (24). This protein is typically expressed in neoplasms originating from mesenchymal tissues; sarcomas, lymphomas, malignant melanomas, and schwannomas are virtually always vimentin-positive (37). Additionally, mesoderm derived carcinomas, like renal cell carcinoma, adrenocortical carcinoma, and adenocarcinomas of the endometrium and ovary, usually express vimentin, as do many thyroid carcinomas (38).…”

In situ tissue engineering with synthetic self-assembling peptide nanofiber scaffolds, PuraMatrix, for mucosal regeneration in the rat middle-ear

“…41,44,45 A rabbit polyclonal antibody against collagen type III (dilution 1:400) (Abcam, Cambridge, UK) was used as a marker of elaboration of ECM component, 46,47 and a rabbit polyclonal antibody against collagen type IV (dilution, 1:50) (LSL, Tokyo, Japan) was used as a marker of basement membrane. 46,48 A monoclonal antibody against E-cadherin (dilution 1:1000) (BD Biosciences) was used as a marker of the adhesive core of adherens junctions.…”

Vimentin Rearrangement during African Swine Fever Virus Infection Involves Retrograde Transport along Microtubules and Phosphorylation of Vimentin by Calcium Calmodulin Kinase II

“…Vimentin is a major component of type III intermediate filaments found in cells of mesenchymal origin and is also present in cells adapted to tissue culture and many transformed cell lines (6,14,16). Up until recently, intermediate filaments were generally thought to be static structures providing a rigid scaffold that is important for determining the shape and mechanical properties of cells.…”