Epothilone B

Danger

H300 (75%): Fatal if swallowed [Danger Acute toxicity, oral]

P203, P260, P261, P262, P264, P264+P265, P270, P271, P272, P273, P280, P301+P316, P302+P352, P304+P340, P305+P354+P338, P316, P317, P318, P319, P321, P330, P332+P317, P333+P317, P361+P364, P362+P364, P391, P403+P233, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 4 reports by companies from 4 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

4,17-Dioxabicyclo14.1.0heptadecane-5,9-dione, 7,11-dihydroxy-8,8,10,12,16-pentamethyl-3-(1E)-1-methyl-2-(2-methyl-4-thiazolyl)ethenyl-, (1S,3S,7S,10R,11S,12S,16R)-: Does not have an individual approval but may be used as a component in a product covered by a group standard. It is not approved for use as a chemical in its own right.

The principal mechanism of the epothilone class is inhibition of microtubule function. Microtubules are essential to cell division, and epothilones therefore stop cells from properly dividing. Epothilone B possess the same biological effects as taxol both in vitro and in cultured cells. This is because they share the same binding site, as well as binding affinity to the microtubule. Like taxol, epothilone B binds to the αβ-tubulin heterodimer subunit. Once bound, the rate of αβ-tubulin dissociation decreases, thus stabilizing the microtubules. Furthermore, epothilone B has also been shown to induce tubulin polymerization into microtubules without the presence of GTP. This is caused by formation of microtubule bundles throughout the cytoplasm. Finally, epothilone B also causes cell cycle arrest at the G2-M transition phase, thus leading to cytotoxicity and eventually cell apoptosis.

Substances that inhibit or prevent the proliferation of NEOPLASMS.

Agents that interact with TUBULIN to inhibit or promote polymerization of MICROTUBULES.