The mechanism of action by which salinomycin kills cancer stem cells involves lysosomal iron sequestration, leading to the production of reactive oxygen species, lysosome membrane permeabilization and ferroptosis.[6] Studies performed in 2011 showed that salinomycin could induce apoptosis of human cancer cells at higher concentrations. C20 amino derivatives such as ironomycin have shown to be more potent in vitro models of persister cancer cells and in vivo doi:10.1038/nchem.2778. Promising results from a few clinical pilot studies reveal that salinomycin is able to effectively eliminate cancer stem cells and to induce partial clinical regression of heavily pretreated and therapy-resistant cancers. The ability of salinomycin to kill both cancer stem cells and therapy-resistant cancer cells (persister) may define the compound as a novel and an effective anticancer drug.[7][8] It has been also shown that salinomycin and its derivatives exhibit potent antiproliferative activity against the drug-resistant cancer cell lines.[9][10] Salinomycin is the key compound in the pharmaceutical company Verastem's efforts to produce an anti-cancer-stem-cell drug.[citation needed]
A team from the University of Cambridge has cloned and sequenced the biosynthetic cluster responsible for salinomycin production, from Streptomyces albus DSM 41398.[11] This has shown that the polyketide backbone of salinomycin is synthesised on an assembly line of nine polyketide synthase) multienzymes. Furthermore, the cluster contains genes involved in oxidative cyclization including salC (epoxidase) and salBI/BII/BIII (epoxide hydrolase) genes. The cluster also contains genes suspected to be involved in self-resistance, export, precursor supply and regulation. The cluster contains a NRPS[clarification needed]-like carrier protein, SalX, that is suspected to tether “pre-salinomycin” during oxidative cyclization. By inactivating salC the researchers have demonstrated that salinomycin biosynthesis proceeds via a diene intermediate.[citation needed]
See also
Narasin a derivative of salinomycin which has an additional methyl group.
^Yurkovich, Marie E.; Tyrakis, Petros A.; Hong, Hui; Sun, Yuhui; Samborskyy, Markiyan; Kamiya, Kohei; Leadlay, Peter F.; et al. (2011-11-11). "A Late-Stage Intermediate in Salinomycin Biosynthesis Is Revealed by Specific Mutation in the Biosynthetic Gene Cluster". ChemBioChem. 13 (1): 66–71. doi:10.1002/cbic.201100590. PMID22076845. S2CID22332727.