Noscapine and its derivatives as microtubule-targeted cancer therapeutics

Noscapine, a phthalideisoquinoline alkaloid, is the second most abundant opium alkaloid derived from the opium poppy, Papaver somniferum. The anti-mitotic potential of noscapine was recently discovered, with no visible toxicity in the vital organs of tumour-implanted mice. Moreover, the low susceptibility of noscapine to the common multi-drug resistance (MDR) through increased efflux by drug transporters (ABCB1 and ABCG2) is of significant importance. Although noscapine possesses low cytotoxic activity, several semisynthetic noscapine derivatives have been reported to show a vast improvement in cytotoxic activity against various cancer cell lines, indicating the potential for noscapine to be developed for clinical use.