A mechanism by which cancer cells can evade an immune response involves an alteration in the amount of MIC on the cell surface b
y _________. Group of answer choices cleavage of MIC at the cell surface by a protease decreasing the level of MIC transcription switching from a transmembrane form of MIC to a secreted form cytosolic degradation of MIC in proteasomes alternative mRNA splicing resulting in a truncated form of MIC that is no longer able to bind to NKG2D
The immune system refers to a complex network of cells and proteins that function to eliminate potentially tumorigenic cells on a daily basis. However, cancer cells show mechanisms in order to escape immune responses. MHC class I chain-related proteins A and B (MICA and MICB) are expressed in normal and tumorigenic cells where they act as ligands of the NKG2D receptor. The expression level of these proteins (MICA and MICB) is finely regulated by the activity of metalloproteinases (i.e., by protease-mediated cleavage), but this mechanism is altered in cancer cells. Recently, drug therapies that stimulate NKG2D mediated tumor destruction by reducing the cleavage of MICA and MICB from the surface of cancer cells have been developed.
