Monday 9 January 2006
Tenascin, also known as hexabrachion and cytotactin, is an extracellular matrix protein with a spatially and temporally restricted tissue distribution.
It is a hexomeric, multidomain protein with disulfide-linked subunits of 190 to 240 kD, originally characterized as ’myotendinous antigen.’
In the embryo it is present in dense mesenchyme surrounding developing epithelia, in tendon anlagen, and in developing cartilage and bone.
In the adult tenascin remains present in tendons and myotendinous junctions in the perichondrium and periosteum, as well as in smooth muscle.
The tenacin family consist of large multimeric proteins involved in morphogenesis and cell adhesion.
Association of invasion-promoting tenascin-C additional domains with breast cancers in young women. (20678196)
- In these malignant gliomas as well as in GBM cell lines, NOTCH2 protein is strongly expressed.
- In a GBM tumor tissue microarray, RBPJk protein, a Notch2 cofactor for transcription, was found to be significantly coexpressed with TNC.
- The TNC gene is transactivated by NOTCH2 in an RBPJk-dependent manner mediated by an RBPJk binding element in the TNC promoter.
- The transactivation is abrogated by a NOTCH2 mutation. This L1711M mutation resides in the RAM domain, the site of interaction between Notch2 and RBPJk.
- In addition, transfection of constructs encoding activated NOTCH2 or NOTCH1 increased endogenous TNC expression identifying TNC as a novel Notch target gene.
- Overexpression of a dominant negative form of the transcriptional coactivator MAML1 or knocking down RBPJk in LN319 cells led to a dramatic decrease in TNC protein levels accompanied by a significant reduction of cell migration.
- Because addition of purified TNC stimulated glioma cell migration, this represents a mechanism for the invasive properties of glioma cells controlled by Notch signaling and defines a novel oncogenic pathway in gliomagenesis that may be targeted for therapeutic intervention in GBM patients.
|Tenascin in the tumor||80%||80%|
|Tenascin at the dermal-epidermal junction||100%||0%|
Tenascin C and tenascin XB (TNXB) are possibly involved in tumorigenesis associated with neurofibromatosis type 1. (17202312)
Microarray-based identification of tenascin C and tenascin XB, genes possibly involved in tumorigenesis associated with neurofibromatosis type 1. Lévy P, Ripoche H, Laurendeau I, Lazar V, Ortonne N, Parfait B, Leroy K, Wechsler J, Salmon I, Wolkenstein P, Dessen P, Vidaud M, Vidaud D, Bièche I. Clin Cancer Res. 2007 Jan 15;13(2 Pt 1):398-407. PMID: 17202312