title: A proteomic approach to cisplatin resistance in the cervix squamous cell carcinoma cell line A431.
abstract: Since drug resistance is a complex and multifactorial event involving activation/repression of multiple biochemical pathways, we used a proteomic approach to study cisplatin resistance and drug response in human tumor cell lines. The cervix squamous cell carcinoma cell line A431 and its cisplatin-resistant subline, A431/Pt, were used as a model system. The experimental set-up involved not just a two-way comparison of the control vs. the drug-resistant cell line, but also an acute cisplatin treatment of both cell lines, leading to a four-way comparison, as follows: 1) A431 vs. A431/Pt cells; 2) A431 vs. A431 cisplatin exposed cells; 3) A431/Pt vs. A431/Pt cisplatin exposed cells; 4) A431 cisplatin exposed cells vs. A431/Pt cisplatin exposed cells. We found modulation of proteins, which could be classified under various categories, such as molecular chaperones (e.g. heat-shock proteins HSP60, HSP90, HSC71, heat-shock cognate 71 kDa protein), Ca2+-binding proteins (e.g. calmodulin, calumenin), proteins involved in drug detoxification (such as peroxiredoxins PRX 2 and PRX 6, and glutathione-S-transferase, GST), anti-apoptotic proteins (such as 14-3-3 switched on in cisplatin-exposed cells) and ion channels (such as VDAC-1, voltage-dependent anion-selective channel). In particular, the basal levels of HSC71 and HSP60 were increased in A431/Pt cells as compared to A431 cells, and cisplatin exposure resulted in up-regulation of HSP60 and HSP90 only in A431 cells. Moreover, cisplatin exposure up-regulated the anti-apoptotic 14-3-3 protein in both cell lines, GST in sensitive cells and PRX6 in A431/Pt cells. These findings are consistent with a constitutive expression of defence factors by resistant cells and with activation by cisplatin of mechanisms acting to protect cells from drug-induced damage. This pattern of response, also observed in parental cells, could reflect an intrinsic resistance of this tumor type.
authors.affiliation: University of Verona, Department of Agricultural and Industrial Biotechnologies, Verona, Italy.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Castagna
authors.forename: Paolo
authors.initials: P
authors.lastname: Antonioli
authors.forename: Hubert
authors.initials: H
authors.lastname: Astner
authors.forename: Mahmoud
authors.initials: M
authors.lastname: Hamdan
authors.forename: Sabina Carla
authors.initials: SC
authors.lastname: Righetti
authors.forename: Paola
authors.initials: P
authors.lastname: Perego
authors.forename: Franco
authors.initials: F
authors.lastname: Zunino
authors.forename: Pier Giorgio
authors.initials: PG
authors.lastname: Righetti
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy*; D002460:Cell Line; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000494:pharmacology*; D019295:Computational Biology; D019008:Drug Resistance, Neoplasm; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods; D020543:Proteome; D040901:Proteomics / Q000379:methods*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012984:Software; D013997:Time Factors; D002583:Uterine Cervical Neoplasms / Q000188:drug therapy*
chemical_list: D000970:Antineoplastic Agents; D020543:Proteome; D002945:Cisplatin