1U65

Ache W. CPT-11

Summary for 1U65

• Entry DOI: 10.2210/pdb1u65/pdb
• Descriptor: Acetylcholinesterase, beta-L-fucopyranose-(1-3)-2-acetamido-2-deoxy-beta-D-glucopyranose, alpha-L-fucopyranose-(1-3)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (8 entities in total)
• Functional Keywords: torpedo ache, anticancer prodrug cpt-11, israel structural proteomics center, ispc, structural genomics, hydrolase
• Biological source: Torpedo californica (Pacific electric ray)
• Cellular location: Isoform H: Cell membrane; Lipid-anchor, GPI- anchor. Isoform T: Cell membrane; Peripheral membrane protein: P04058
• Total number of polymer chains: 1
• Total formula weight: 63599.14

Authors

Harel, M.,Hyatt, J.L.,Brumshtein, B.,Morton, C.L.,Wadkins, R.W.,Silman, I.,Sussman, J.L.,Potter, P.M.,Israel Structural Proteomics Center (ISPC) (deposition date: 2004-07-29, release date: 2005-07-19, Last modification date: 2024-11-13)

Primary citation

Harel, M.,Hyatt, J.L.,Brumshtein, B.,Morton, C.L.,Yoon, K.J.,Wadkins, R.M.,Silman, I.,Sussman, J.L.,Potter, P.M.
The crystal structure of the complex of the anticancer prodrug 7-ethyl-10-[4-(1-piperidino)-1-piperidino]-carbonyloxycamptothecin (CPT-11) with Torpedo californica acetylcholinesterase provides a molecular explanation for its cholinergic action
Mol.Pharmacol., 67:1874-1881, 2005

PubMed Abstract: The anticancer prodrug 7-ethyl-10-[4-(1-piperidino)-1-piperidino-]carbonyloxycamptothecin (CPT-11) is a highly effective camptothecin analog that has been approved for the treatment of colon cancer. It is hydrolyzed by carboxylesterases to yield 7-ethyl-10-hydroxycamptothecin (SN-38), a potent topoisomerase I poison. However, upon high-dose intravenous administration of CPT-11, a cholinergic syndrome is observed that can be ameliorated by atropine. Previous studies have indicated that CPT-11 can inhibit acetylcholinesterase (AChE), and here, we provide a detailed analysis of the inhibition of AChE by CPT-11 and by structural analogs. These studies demonstrate that the terminal dipiperidino moiety in CPT-11 plays a major role in enzyme inhibition, and this has been confirmed by X-ray crystallographic studies of a complex of the drug with Torpedo californica AChE. Our results indicate that CPT-11 binds within the active site gorge of the protein in a fashion similar to that observed with the Alzheimer drug donepezil. The 3D structure of the CPT-11/AChE complex also permits modeling of CPT-11 complexed with mammalian butyrylcholinesterase and carboxylesterase, both of which are known to hydrolyze the drug to the active metabolite. Overall, the results presented here clarify the mechanism of AChE inhibition by CPT-11 and detail the interaction of the drug with the protein. These studies may allow the design of both novel camptothecin analogs that would not inhibit AChE and new AChE inhibitors derived from the camptothecin scaffold.

PubMed: 15772291
DOI: 10.1124/mol.104.009944

Experimental method

X-RAY DIFFRACTION (2.61 Å)