@article {Kubo1482, author = {Takashi Kubo and Su-Ryang Kim and Kimie Sai and Yoshiro Saito and Toshiharu Nakajima and Kenji Matsumoto and Hirohisa Saito and Kuniaki Shirao and Noboru Yamamoto and Hironobu Minami and Atsushi Ohtsu and Teruhiko Yoshida and Nagahiro Saijo and Yasuo Ohno and Shogo Ozawa and Jun-ichi Sawada}, title = {FUNCTIONAL CHARACTERIZATION OF THREE NATURALLY OCCURRING SINGLE NUCLEOTIDE POLYMORPHISMS IN THE CES2 GENE ENCODING CARBOXYLESTERASE 2 (HCE-2)}, volume = {33}, number = {10}, pages = {1482--1487}, year = {2005}, doi = {10.1124/dmd.105.005587}, publisher = {American Society for Pharmacology and Experimental Therapeutics}, abstract = {Twelve single nucleotide polymorphisms (SNPs) in the human CES2 gene, which encodes a carboxylesterase, hCE-2 [human carboxylesterase 2 (EC 3.1.1.1)], have been reported in the Japanese [S. R. Kim, T. Nakamura, Y. Saito, K. Sai, T. Nakajima, H. Saito, K. Shirao, H. Minami, A. Ohtsu, T. Yoshida, et al. (2003) Drug Metab Pharmacokinet 18:327{\textendash}332). In this report, we have examined functional alterations of three SNPs, a nonsynonymous SNP (100C\>T, R34W), an SNP at the splice acceptor site in intron 8 (IVS8-2A\>G), and one newly discovered nonsynonymous SNP (424G\>A, V142M). For the two nonsynonymous SNPs, the corresponding variant cDNAs were expressed in COS-1 cells. Both the R34W and V142M variants showed little esterase activities toward the anticancer agent irinotecan and two typical carboxylesterase substrates, p-nitrophenol acetate and 4-methylumbelliferyl acetate, although increased levels of cDNA-mediated protein expression were observed by Western blotting as compared with the wild type. To investigate a possible splicing aberration in IVS8-2A\>G, an in vitro splicing assay was utilized and transcripts derived from CES2 gene fragments of the wild type and IVS8-2A\>G were compared. Sequence analysis of the cloned transcripts revealed that IVS8-2A\>G yielded mostly aberrantly spliced transcripts, including a deleted exon or a 32-bp deletion proximal to the 5' end of exon 9, which resulted in truncated hCE-2 proteins. These results suggested that 100C\>T (R34W), 424G\>A (V142M), and IVS8-2A\>G are functionally deficient SNPs. The American Society for Pharmacology and Experimental Therapeutics}, issn = {0090-9556}, URL = {https://dmd.aspetjournals.org/content/33/10/1482}, eprint = {https://dmd.aspetjournals.org/content/33/10/1482.full.pdf}, journal = {Drug Metabolism and Disposition} }