Merck, A4882-5G, 6-Thioguanine

General description
6-Thioguanine is a variant of guanine with hydrogen bonding at the N-7 of the purine ring. Its association with cytosine alters the dimension of the base stacking. 6-Thioguanine usage in treating inflammatory bowel disease (IBD) contributes to nodular regenerative hyperplasia (NRH) in the liver.
Application
6-Thioguanine has been used:
to induce autophagy and apoptosis in colorectal cancer cell lines HCT116
as a selection marker in the mutation and survival assay in chinese hamster lung fibroblasts culture V79
as a selection marker in clonogenic Lung metastasis assay of 4T1-luc cells

Biochem/physiol Actions
Antimetabolite used in the treatment of leukemias. Competes with hypoxanthine and guanine for the enzyme hypoxanthine-guanine phosphoribosyltransferase, which catalzyes a critical step in the generation of purine nucleotides.
Ribosylated and phosphorylated by the same pathway as natural purine bases; as the nucleotide, inhibits a variety of cellular processes involved in nucleic acid synthesis. Has a long history as an effective treatment of leukemia.