For research use only. Not for therapeutic Use.
Indoximod (1-Methyl-D-tryptophan) is an orally active indoleamine 2,3-dioxygenase (IDO) pathway inhibitor. Indoximod acts as a Trp mimetic in regulating mTOR. Indoximod is an immunometabolic adjuvant used for the research of cancer[1][2].
The IDO inhibitor 1-methyl-tryptophan exists in two stereoisomers with potentially different biological properties. The L isomer is the more potent inhibitor of IDO activity using the purified enzyme and in HeLa cell–based assays. However, the D isomer is significantly more effective in reversing the suppression of T cells created by IDO-expressing dendritic cells. The L isomer of 1-methyl-tryptophan functioned as a competitive inhibitor (Ki=19 μM), whereas the d isomer is much less effective. The DL mixture is intermediate, with a Ki of 35 μM[1].
The D isomer is more efficacious as an anticancer agent in chemo-immunotherapy regimens using NSC-26271, NSC 125973, or LY 188011, when tested in mouse models of transplantable melanoma and transplantable and autochthonous breast cancer. The D isomer of 1-methyl-tryptophan specifically targets the IDO gene because the antitumor effect of d-1-methyl-tryptophan is completely lost in mice with a disruption of the IDO gene (IDO-knockout mice). Oral administration of dl-1-methyl-tryptophan in combination with NSC 125973 can elicit regression of autochthonous breast tumors[1].
Catalog Number | I000417 |
CAS Number | 110117-83-4 |
Synonyms | (2R)-2-amino-3-(1-methylindol-3-yl)propanoic acid |
Molecular Formula | C12H14N2O2 |
Purity | ≥95% |
InChI | InChI=1S/C12H14N2O2/c1-14-7-8(6-10(13)12(15)16)9-4-2-3-5-11(9)14/h2-5,7,10H,6,13H2,1H3,(H,15,16)/t10-/m1/s1 |
InChIKey | ZADWXFSZEAPBJS-SNVBAGLBSA-N |
SMILES | CN1C=C(C2=CC=CC=C21)CC(C(=O)O)N |
Reference | [1]. Hou DY, et al. Inhibition of indoleamine 2,3-dioxygenase in dendritic cells by stereoisomers of 1-methyl-tryptophancorrelates with antitumor responses. Cancer Res. 2007 Jan 15;67(2):792-801. [2]. Metz R, et al. IDO inhibits a tryptophan sufficiency signal that stimulates mTOR: A novel IDO effector pathway targeted by D-1-methyl-tryptophan. Oncoimmunology. 2012;1(9):1460-1468. |