title: The determinants of sensitivity and acquired resistance to gemcitabine differ in non-small cell lung cancer: a role of ABCC5 in gemcitabine sensitivity.
abstract: We examined the expression levels of the multidrug resistance protein 5 (ABCC5) gene in non-small cell lung cancer (NSCLC) cell lines to clarify the relationship with the sensitivity to gemcitabine. The expression levels of ABCC5 were inversely correlated with gemcitabine sensitivity significantly (r = 0.628; P < 0.01) in 17 NSCLC cells, whereas the expression of ABCC5 in the gemcitabine-resistant NSCLC cell line H23/GEM-R was the same as that in parental NCI-H23 cells. Treatment with the ABCC5 inhibitor zaprinast altered the sensitivity to gemcitabine in ABCC5-expressing NSCLC cells. In addition, decreasing the expression of ABCC5 by small interfering RNA altered the cytotoxicity to gemcitabine. These results indicate that modulation of ABCC5 activity could be used to increase the gemcitabine sensitivity in NSCLC. Previously, we found a decreased expression of deoxycytidine kinase in H23/GEM-R cells, and further investigation in this study showed an increased expression of ribonucleotide reductase subunit 1 in H23/GEM-R cells. We therefore also examined the effect of modifying the expression of both genes on gemcitabine resistance. We found that using small interfering RNA to decrease the expression of ribonucleotide reductase subunit 1 resulted in a decreased resistance to gemcitabine in H23/GEM-R cells. Furthermore, pretreatment with pemetrexed resulted in an increased deoxycytidine kinase expression concomitant with the alteration of the resistance to gemcitabine in H23/GEM-R cells. The determinants for sensitivity and the acquired resistance in gemcitabine are quite different; nonetheless, modification of these factors may increase the efficacy of gemcitabine in the treatment of NSCLC.
authors.affiliation: Department of Internal Medicine and Molecular Science, Nagoya City University Graduate School of Medical Sciences, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya 467-8601, Japan. t-oguri@med.nagoya-cu.ac.jp
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Oguri
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Achiwa
authors.forename: Shigeki
authors.initials: S
authors.lastname: Sato
authors.forename: Yuji
authors.initials: Y
authors.lastname: Bessho
authors.forename: Yuko
authors.initials: Y
authors.lastname: Takano
authors.forename: Mikinori
authors.initials: M
authors.lastname: Miyazaki
authors.forename: Hideki
authors.initials: H
authors.lastname: Muramatsu
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Maeda
authors.forename: Takashi
authors.initials: T
authors.lastname: Niimi
authors.forename: Ryuzo
authors.initials: R
authors.lastname: Ueda
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology / Q000627:therapeutic use*; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000235:genetics; D045744:Cell Line, Tumor; D003841:Deoxycytidine / Q000031:analogs & derivatives* / Q000627:therapeutic use; D019008:Drug Resistance, Neoplasm / Q000187:drug effects / Q000235:genetics*; D015870:Gene Expression; D005971:Glutamates / Q000494:pharmacology; D006147:Guanine / Q000031:analogs & derivatives / Q000494:pharmacology; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000235:genetics; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D000068437:Pemetrexed; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D011688:Purinones / Q000494:pharmacology; D034741:RNA, Small Interfering / Q000235:genetics / Q000494:pharmacology; D012262:Ribonucleoside Diphosphate Reductase; D025521:Tumor Suppressor Proteins / Q000037:antagonists & inhibitors / Q000235:genetics; D000093542:Gemcitabine
chemical_list: D000964:Antimetabolites, Antineoplastic; D003841:Deoxycytidine; D005971:Glutamates; D006147:Guanine; D027425:ATP-Binding Cassette, Sub-Family C Proteins; D000068437:Pemetrexed; D010726:Phosphodiesterase Inhibitors; D011688:Purinones; D034741:RNA, Small Interfering; D012262:Ribonucleoside Diphosphate Reductase; D025521:Tumor Suppressor Proteins; D000093542:Gemcitabine; C120809:ABCC5 protein, human; C475286:RRM1 protein, human; C011145:zaprinast