Tumor necrosis factors

Overview
Tumor necrosis factors (or the TNF-family) refers to a group of cytokines family that can cause apoptosis.

Mechanism
TNF acts via the TNF Receptor (TNF-R) and is part of the extrinsic pathway for triggering apoptosis. TNF-R is associated with procaspases through adapter proteins (FADD, TRADD, etc.) that can cleave other inactive procaspases and trigger the caspase cascade, irreversibly committing the cell to apoptosis.

TNF interacts with tumor cells to trigger cytolysis or cell death.

TNF can interact with receptors on epithelial cells, which leads to increased vascular permeability allowing leukocytes access to the site of infection. This is a type of localized inflammatory response, although systemic release may lead to septic shock and death.

Types

 * Tumor necrosis factor-alpha (TNF-α) is the most well-known member of this class, and sometimes referred to when the term "tumor necrosis factor" is used.


 * Tumor necrosis factor-beta (TNF-β) is a cytokine that is induced by interleukin 10