U0126

U0126 is the 'code' name for a compound associated with cancer treatment and also in preventing ischemia and cellular oxidative stress. It also has likely utility in strokes and heart attacks. This compound is available for research purposes from a number of companies.

The specific compound is not approved by the FDA as a therapeutic agent, though it has been used in medical settings. Members of this broad class of chemical compounds have been approved by the US FDA for the treatment of specific cancers.

It is a highly selective inhibitor of both MEK1 and MEK2, a type of MAPK/ERK kinase. U0126 was found to functionally antagonize AP-1 transcriptional activity via noncompetitive inhibition of the dual specificity kinase MEK with IC50 of 72 nM for MEK1 and 58 nM for MEK2. U0126 inhibited anchorage-independent growth of Ki-ras-transformed rat fibroblasts by simultaneously blocking both extracellular signal-regulated kinase (ERK) and mammalian target of rapamycin (mTOR)-p70(S6K) pathways.

The effects of U0126 on the growth of eight human breast cancer cell lines shown that U0126 selectively repressed anchorage-independent growth of MDA-MB231 and HBC4 cells, two lines with constitutively activated ERK. Loss of contact with substratum triggers apoptosis in many normal cell types, a phenomenon termed anoikis. U0126 sensitized MDA-MB231 and HBC4 to anoikis, i.e., upon treatment with U0126, cells deprived of anchorage entered apoptosis.

U0126 is also a weak inhibitor of PKC, Raf, ERK, JNK, MEKK, MKK-3, MKK-4/SEK, MKK-6, Cdk2 and Cdk4.

Its potential for wiping long-term memories in rats has been studied at the Center for Neural Science at New York University.