VIM

(Vimentin)
Characteristics

Vimentin (57 kDa) is the most ubiquituos intermediate filament protein and the first to be expressed during cell differentiation. All primitive cell types express vimentin but in most non-mesenchymal cells it is replaced by other intermediate filament proteins during differentiation. Vimentin is expressed in a wide variety of mesenchymal cell types: fibroblasts, endothelial cells etc., and in a number of other cell types derived from mesoderm, e.g., mesothelium and ovarian granulosa cells. However, in non-vascular smooth muscle cells, vimentin is often replaced by desmin. In striated muscle, vimetin is also replaced by desmin. However, during regeneration, vimentin is reexpressed. Cells of the lymfo-haemopoietic system (lymphocytes, macrophages etc.) also express vimentin, sometimes in scarce amounts. Vimentin is also found in mesoderm derived epithelia, e.g. kidney (Bowman capsule), endometrium and ovary (surface epithelium), in myoepithelial cells (breast, salivary and sweat glands), an in thyroid gland epithelium. In these cell types, as in mesothelial cells, vimentin is coexpressed with cytokeratin. Furthermore, vimentin is detected in many cells from the neural crest. Particularly melanocytes express abundant vimentin. In glial cells vimentin is coexpressed with glial filament acidic protein (GFAP).

Neoplasms

Vimentin is present in many different neoplasms but is particulary expressed in those originated from mesenchymal cells. Sarcomas e.g., fibrosarcoma, malignt fibrous histiocytoma, angiosarcoma, and leio- and rhabdomyosarcoma, as well as lymphomas, malignant melanoma and schwannoma, are virtually always vimentin positive. Mesoderm derived carcinomas like renal cell carcinoma, adrenal cortical carcinoma and adenocarcinomas from endometrium and ovary usually express vimentin. Also thyroid carcinomas are vimentin positive. Any low differentiated or sarcomatoid carcinoma may express some vimentin.

Application

Vimentin is frequently included in the so-called primary panel (together with CD45, cytokeratin, and S-100 protein): Intense staining reaction for vimentin without coexpression of other intermediate filament proteins is strongly suggestive of a mesenchymal tumour or a malignant melanoma. However, in biopsies representing only a sarcomatoid part of renal cell carcinoma a.o. a strong positivity for vimentin without cytokeratin expression may be seen. Tumours like lymphomas and seminomas have the same intermediate filament profile, but the vimentin expression is usually weaker.

Controls

Liver, colon and pancreas are recommended as controls.

In liver, the protocol must be calibrated to give an intense staining reaction of virtually all Kupffer cells, whereas, endothelial cells of the sinusoids must display an at least weak intensity. Liver cells should be negative.

In the colon, dispersed intraepithelial T-cells must show an at least moderate staining reaction. Endothelial cells of large vessels and stromal cells (e.g. fibroblasts and lymphocytes) must display a strong but distinct cytoplasmic staining intensity. Epithelial cells of the colon mucosa should be negative.

In the pancreas, the vast majority of epithelial cells of exocrine acini should display a weak to strong predominantly cytoplasmic staining reaction.

Selected references

Azumi, N., Battifora, H. The distribution of vimentin and keratin in epithelial and nonepithelial neoplasms. A comprehensive immunohistochemical study on formalin- and alcohol-fixed tumors. Am J Clin Pathol 1987;88:286-96. Battifora H. Assesment of antigen damage in immunohistochemistry. Am J Clin Pathol. 1991;88:669-671. Cote RJ, Cordon-Cardo C, Reuter VE, Rosen PP. Immunopathology of adrenal and renal cortical tumors. Coordinated change in antigen expression is associated with neoplastic conversion in the adrenal cortex. Am J Pathol. 1990 May;136(5):1077-84. Guan XY. Association of Vimentin overexpression and hepatocellular carcinoma metastasis. Oncogene. 2004 Jan 8;23(1):298-302. Khoury JD, Abrahams NA, Levin HS, MacLennan GT. The utility of epithelial membrane antigen and vimentin in the diagnosis of chromophobe renal cell carcinoma. Ann Diagn Pathol. 2002 Jun;6(3):154-8. Lang SH, Hyde C, Reid IN, Hitchcock IS, Hart CA, Bryden AA, Villette JM, Stower MJ, Maitland NJ. Enhanced expression of vimentin in motile prostate cell lines and in poorly differentiated and metastatic prostate carcinoma. Prostate. 2002 Sep 1;52(4):253-63. Niveditha SR, Bajaj P. Vimentin expression in breast carcinomas. Indian J Pathol Microbiol. 2003 Oct;46(4):579-84. Ramaekers FCS, Vroom TM, Moesker O, et al. The use of antibodies to intermediate filament proteins in the differential diagnosis of lymphoma versus metastatic carcinoma. Histochem J. 1985;17:57. Sembritzki O, Hagel C, Lamszus K, Deppert W, Bohn W. Cytoplasmic localization of wild-type p53 in glioblastomas correlates with expression of vimentin and glial fibrillary acidic protein. Neuro-oncol. 2002 Jul;4(3):171-8. Utsunomiya T, Yao T, Tamiya S, Tsuneyoshi M. Intracellular distribution of intermediate filaments in vimentin-positive gastric carcinomas: confocal laser scanning microscopy using formalin-fixed paraffin-embedded specimens. Pathol Res Pract. 2002;198(2):69-76.

22.11.10 - SN/MV/LE