title: Proteomic analysis of ubiquitination-associated proteins in a cisplatin-resistant             human lung adenocarcinoma cell line.
abstract: The objective of this study was to screen for ubiquitination-associated             proteins involved in cisplatin resistance in a human lung adenocarcinoma cell             strain using a comparative proteomic strategy. We employed 1D SDS-PAGE to separate             ubiquitinated proteins isolated and enriched from A549 and A549/CDDP lysates via             affinity chromatography. The differentially expressed bands between 45-85 kDa             were subsequently hydrolyzed by trypsin and subjected to HPLC-CHIP-MS/MS analysis.             Of the 11 proteins identified, 7 proteins were monoubiquitinated or polyubiquitinated             substrates and 4 proteins were E3 ubiquitin ligase-associated proteins. The results             of western blotting and confocal laser scanning microscopy indicated that the             expression levels of the E3 ubiquitin ligases RNF6, LRSAM1 and TRIM25 in A549             cells were significantly lower than those in the A549/CDDP cell line. The expression             levels of the above three ubiquitin ligases in both cell lines were significantly             decreased upon treatment with cis-diamminedichloroplatinum (CDDP), and the expression             in the A549/CDDP cell after the treatment with CDDP decreased to a lesser extent.             The expression of the substrate PKM2 in the A549 cell was higher than that in             the A549/CDDP cells. Moreover, the expression of PKM2 increased in the A549 cell             line and decreased in the A549/CDDP cell line upon CDDP treatment. This study             suggests that drug resistance is closely correlated with changes in the ubiquitination             process at the protein level in a human lung adenocarcinoma cell line.
authors.affiliation: The First Affiliated Hospital of Chongqing Medical University,                     Chongqing, P.R. China.
authors.forename: Xia
authors.initials: X
authors.lastname: Qin
authors.forename: Shizhi
authors.initials: S
authors.lastname: Chen
authors.forename: Zongyin
authors.initials: Z
authors.lastname: Qiu
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhang
authors.forename: Feng
authors.initials: F
authors.lastname: Qiu
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000378:metabolism; D000077192:Adenocarcinoma of Lung; D000970:Antineoplastic Agents / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000378:metabolism; D020543:Proteome / Q000378:metabolism*; D040901:Proteomics; D053719:Tandem Mass Spectrometry; D025801:Ubiquitin / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism; D054875:Ubiquitination / Q000187:drug effects*
chemical_list: D000970:Antineoplastic Agents; D020543:Proteome; D025801:Ubiquitin; D044767:Ubiquitin-Protein Ligases; D002945:Cisplatin