title: Reversal of multidrug resistance of vincristine-resistant gastric adenocarcinoma cells through up-regulation of DARPP-32.
abstract: Here we investigated the roles of DARPP-32 in multidrug resistance (MDR) of gastric cancer cells and the possible underlying mechanisms. We constructed the eukaryotic expression vector of DARPP-32 and transfected it into human vincristine-resistant gastric adenocarcinoma cell line SGC7901/VCR. Up-regulation of DARPP-32 could significantly enhance the sensitivity of SGC7901/VCR cells towards vincristine, adriamycin, 5-fluorouracil and cisplatin, and could decrease the capacity of cells to efflux adriamycin. What's more, the results of subrenal capsule assay confirmed that DARPP-32 might play a certain role in MDR of gastric cancer. DARPP-32 could significantly down-regulate the expression of P-gp and zinc ribbon domain-containing 1 (ZNRD1), but not alter the expression of multidrug resistance-associated protein (MRP) or the glutathione S-transferase (GST). DARPP-32 could also significantly decrease the anti-apoptotic activity of SGC7901/VCR cells. Further study of the biological functions of DARPP-32 might be helpful for understanding the mechanisms of MDR in gastric cancer.
authors.affiliation: State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, Fourth Military Medical University, Changlexi ST 15, Xi'an 710032, Shaanxi Province, China.
authors.forename: Liu
authors.initials: L
authors.lastname: Hong
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
authors.forename: Ying
authors.initials: Y
authors.lastname: Han
authors.forename: Yunping
authors.initials: Y
authors.lastname: Zhao
authors.forename: Juan
authors.initials: J
authors.lastname: Gao
authors.forename: Jun
authors.initials: J
authors.lastname: Wang
authors.forename: Yu
authors.initials: Y
authors.lastname: Han
authors.forename: Xiaoyin
authors.initials: X
authors.lastname: Zhang
authors.forename: Li
authors.initials: L
authors.lastname: Yan
authors.forename: Xinmin
authors.initials: X
authors.lastname: Zhou
authors.forename: Taidong
authors.initials: T
authors.lastname: Qiao
authors.forename: Zhen
authors.initials: Z
authors.lastname: Chen
authors.forename: Daiming
authors.initials: D
authors.lastname: Fan
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D051937:Dopamine and cAMP-Regulated Phosphoprotein 32 / Q000235:genetics* / Q000378:metabolism; D004317:Doxorubicin / Q000494:pharmacology; D018432:Drug Resistance, Multiple; D019008:Drug Resistance, Neoplasm; D004354:Drug Screening Assays, Antitumor; D005453:Fluorescence; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D005982:Glutathione Transferase / Q000378:metabolism; D006801:Humans; D020128:Inhibitory Concentration 50; D051379:Mice; D008819:Mice, Nude; D013274:Stomach Neoplasms / Q000235:genetics* / Q000473:pathology; D014162:Transfection; D015854:Up-Regulation / Q000235:genetics*; D014750:Vincristine / Q000494:pharmacology*
chemical_list: D051937:Dopamine and cAMP-Regulated Phosphoprotein 32; D014750:Vincristine; D004317:Doxorubicin; D005982:Glutathione Transferase