Transforming growth factor
From Wikipedia, the free encyclopedia
Transforming growth factor (TGF) is used to describe two classes of polypeptide growth factors, TGFα and TGFβ.
- TGFα is upregulated in some human cancers. It is produced in macrophages, brain cells, and keratinocytes, and induces epithelial development.
- TGFβ exists in at least three known subtypes in humans, TGFβ1, TGFβ2, and TGFβ3. These are upregulated in some human cancers, and play crucial roles in tissue regeneration, cell differentiation, embryonic development, and regulation of the immune system.
These proteins were originally characterized by their capacity to induce oncogenic transformation in a specific cell culture system, rat kidney fibroblasts. Application of the transforming growth factors to normal rat kidney fibroblasts induces the cultured cells to proliferate and overgrow, no longer subject to the normal inhibition caused by contact between cells.
The name "Transforming Growth Factor" is somewhat arbitrary, since the two classes of TGFs are not structurally or genetically related to one another, and they act through different receptor mechanisms. Furthermore, they do not always induce cellular transformation, and are not the only growth factors that induce cellular transformation.
TGFβ receptors are single pass serine/threonine kinase receptors.
[edit] See also
[edit] External Links
- American Association for Cancer Research - Cancer Concepts Factsheet on TGF-beta
- MeSH Transforming+Growth+Factors
Signaling proteins: Hedgehog - Integrin - JAK/STAT (JAK/STAT) - MAPK/ERK pathway (MAPK/ERK) - NF-kB - Notch - p53 - Wnt (Frzb)
Epidermal growth factor - Fibroblast growth factor (FGF2) - Nerve growth factor - Platelet-derived growth factor - Transforming growth factor (TGFα, TGFβ, TGFβ pathway)
