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Scheda a cura di Marco Chilosi
(GYM)
TENASCINA**
marcatore
di fibrogenesi
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Am J Dermatopathol 1996 Oct;18(5):454-9
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Tenascin
expression in cutaneous fibrohistiocytic tumors. Immunohistochemical
investigation of 24 cases.
Franchi A, Santucci M
Institute of Anatomic Pathology, University of Florence Medical School,
Italy.
We studied the immunolocalization of the extracellular matrix glycoprotein
tenascin in a series of 24 cutaneous fibrohistiocytic tumors, including
seven benign lesions (benign fibrous histiocytoma/dermatofibroma), six
intermediate malignancy lesions (dermatofibrosarcoma protuberans), and 11
malignant lesions (three atypical fibroxantomas and eight malignant fibrous
histiocytomas). The results of the immunohistochemical staining were
evaluated semiquantitatively. All lesions expressed tenascin in the
extracellular matrix, with some differences in the distribution of the
immunoreactivity. In benign fibrous histiocytoma and in dermatofibrosarcoma
protuberans, there was a homogeneous, intense, and diffuse staining of the
extracellular matrix (++); the only exception was the homogenized, sclerotic
collagen present in late, regressing benign fibrous histiocytoma, which
showed a weak and patchy reactivity (+). In atypical fibroxantomas and in
malignant fibrous histiocytomas, there was an irregular distribution of the
positivity within the tumor matrix (+). Prominent staining of the cytoplasm
of several neoplastic cells was observed in atypical fibroxantoma and
malignant fibrous histiocytoma (++), focal cytoplasmic staining of scattered
cells was found in dermatofibrosarcoma protuberans (+), and cytoplasmic
staining was absent from benign fibrous histiocytoma (-). These findings
indicate a relationship between cytoplasmic and extracellular matrix
expression of tenascin in these lesions, with an increase in cytoplasmic
staining and a decrease in extracellular matrix staining in the malignant
forms. Based on these different staining patterns, tenascin
immunolocalization could furnish some help in the differential diagnosis
among benign, intermediate malignancy, and malignant cutaneous
fibrohistiocytic tumors. Moreover, the intense tenascin staining at the edge
of the lesion could be helpful in defining its extent and therefore provide
an additional criterion to evaluate the radicality of the surgical
procedure.
Hum Pathol. 2001 Jan;32(1):50-6.
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Tenascin
differentiates dermatofibroma from dermatofibrosarcoma protuberans:
comparison with CD34 and factor XIIIa.
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Kahn HJ, Fekete E, From L.
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Department of
Pathology, Sunnybrook & Women's College Health Science Center, Women's
College Campus, Toronto, Canada.
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Differentiation of dermatofibroma (DF) from dermatofibrosarcoma protuberans
(DFSP) can be difficult. CD34 and Factor XIIIa have been used to
differentiate DF from DFSP. However, there is overlap and lack of
specificity of their expression. Tenascin is an extracellular matrix
glycoprotein that is involved in embryogenesis, carcinogenesis, and wound
healing. The aim of the study was to assess the role of tenascin in DF and
DFSP and compare the results with those obtained with CD34 and Factor XIIIa.
Immunohistochemical staining was performed on 20 cases each of DFSP and DF,
using antibodies to tenascin, CD34 and Factor XIIIa, and the streptavidin
biotin technique. Positivity for all 3 antibodies was assessed within the
tumors. Tenascin expression was also assessed at the dermal-epidermal
junction. Strong tenascin positivity was noted at the dermal-epidermal
junction overlying the lesion in 20 of 20 cases of DF (100%) and was
negative over the lesion in 20 of 20 cases DFSP (100%). Tenascin was noted
within the lesion of 80% of both DF and DFSP (16/20 cases). CD34 was
strongly expressed in 16 of 20 (80%) DFSP and 5 of 20 (25%) DF, whereas
Factor XIIIa was strongly expressed in 19 of 20 (95%) DF and 3 of 15 (15%)
DFSP. Although CD34 was expressed in 80% DFSP and Factor XIIIa in 95% of DF,
there was overlap in their expression in the 2 types of tumors. The
increased expression of tenascin at the dermal-epidermal junction overlying
the lesion in DF but not in DFSP, differentiated these 2 tumors. In contrast,
tenascin expression within the lesion did not differentiate DF from DFSP.
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Distribuzione
nei tessuti normali |
Am J Respir Cell Mol Biol. 2001
Sep;25(3):341-6.
Distribution
and mRNA expression of tenascin-C in developing human lung.
Kaarteenaho-Wiik R, Kinnula V,
Herva R, Paakko P, Pollanen R, Soini Y.
Department of
Internal Medicine, University of Oulu and Oulu University Hospital, Oulu,
Finland.
Tenascin-C is an extracellular matrix glycoprotein that is spatially
expressed during organogenesis, in inflammatory and fibrotic disorders, and
in neoplasms. The aim of this study was to analyze its expression in
developing human lung tissues during pseudoglandular, canalicular, saccular,
and alveolar periods corresponding to Weeks 12 to 40. Lung tissues were
obtained at autopsy from 34 nonmalformed cases. An immunohistochemical
analysis and a messenger RNA (mRNA) in situ hybridization method combined
with light microscopy were used. The extent of tenascin-C immunoreactivity
was scored as absent, low, moderate, or strong in and around different types
of pulmonary cells. The immunohistochemical expression for tenascin-C was
strong beneath the airway epithelium, especially at the sites of airway
subdivision during Weeks 12 to 23, whereas its expression was moderate or
weak underneath alveolar and bronchiolar epithelia between Weeks 24 and 40.
The expression for tenascin-C was strong in the intima of veins, especially
in the canalicular period, i.e., Weeks 17 to 28. A moderate or strong
immunoreactivity for tenascin-C was also observed around chondrocytes in
every case studied during all periods. The increased expression of
tenascin-C mRNA was most often seen in the cells below the airway epithelium.
Taken together, tenascin-C is expressed in human lung during all
developmental periods, and its expression is especially strong below the
airway epithelium at the sites of airway subdivision.
Am
J Pathol. 1993 Nov;143(5):1348-55.
Constitutive
expression of tenascin in T-dependent zones of human lymphoid tissues.
Chilosi
M, Lestani M, Benedetti A, Montagna L, Pedron S, Scarpa A, Menestrina F,
Hirohashi S, Pizzolo G, Semenzato G.
Istituto di Anatomia Pathologica, Universita di Verona,
Italy.
Tenascin is a major
extracellular matrix glycoprotein that can interfere with the action of
fibronectin by inhibiting cell adhesion and spreading. Although tenascin is
able to exert important immunomodulatory activities on T and B cells and
macrophages, little is known about its distribution in different
lymphohemopoietic tissues. In this study we have analyzed tenascin
immunoreactivity on cryostat and paraffin sections of normal and
pathological lymphoid tissues using two different monoclonal antibodies. We
demonstrated strong tenascin expression in all peripheral lymphoid tissues,
whereas it was barely detectable in the thymus and in bone marrow. In
reactive lymph nodes, tenascin was mainly found in T-dependent zones,
forming a variably close-woven reticular network corresponding to
fibroblastic reticulum cells and blood vessels basal laminae, showing a
partial co-localization with fibronectin. In B-dependent zones, tenascin was
restricted to blood vessels. Using double-marker analysis, we performed a
thorough study comparing tenascin expression in different compartments of
lymphoid microenvironments. Tenascin network appeared much thicker in
chronically stimulated tissues, where CD4+ lymphocytes with "memory"
phenotype (CD45RO+/CD45RA-) were predominant, and at sites of ongoing
inflammation. In particular, a striking increase of tenascin was observed in
sarcoid lymph node, as well as in myasthenic hyperplastic thymuses. In
addition, tenascin can be abnormally synthesized in tissue involved by
various types of lymphomas, including Hodgkin's disease and hairy cell
leukemia.
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