title: HSP90 is a promising target in gemcitabine and 5-fluorouracil resistant pancreatic cancer.
abstract: Chemotherapy (CT) options in pancreatic cancer (PC) are limited to gemcitabine and 5-fluorouracil (5-FU). Several identified molecular targets in PC represent client proteins of HSP90. HSP90 is a promising target since it interferes with many oncogenic signaling pathways simultaneously. The aim of this study was to evaluate the efficacy of different HSP90 inhibitors in gemcitabine and 5-FU resistant PC. PC cell lines 5061, 5072 and 5156 were isolated and brought in to culture from patients being operated at our institution. L3.6pl cell line served as a control. Anti-proliferative efficacy of three different HSP90 inhibitors (17-AAG, 17-DMAG and 17-AEPGA) was evaluated by the MTT assay. Alterations in signaling pathway effectors and apoptosis upon HSP90 inhibition were determined by western blot analysis and annexin V/PI staining. The cell lines 5061, 5072 and 5156 were resistant to gemcitabine and 5-FU. In contrast 17-AAG and the water-soluble derivates 17-DMAG and 17-AEPGA displayed high anti-proliferative activity in all tested cell lines. The calculated IC50was below 1 µM. Highly significant down regulation of epidermal-growth-factor-receptor, insulin-like-growth-factor-receptor-1, AKT and MAPK reflected the intracellular molecular signaling-network disruption. Furthermore, besides HSP70 also HSP27 was upregulated in all cell lines. Apoptosis occurred early under HSP90 inhibition and was determined by annexin V/PI staining and CASPASE-3 and PARP assay. In contrast, gemcitabine treated cells did not show any apoptosis. HSP90 inhibition disrupts multiple signaling cascades in gemcitabine and 5-FU resistant PC simultaneously and promotes cancer cell apoptosis. Watersoluble 17-DMAG is equally effective as 17-AAG. HSP27, besides HSP70, may represent an effective response marker of successful HSP90 inhibition.
authors.affiliation: Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
authors.forename: Tarik
authors.initials: T
authors.lastname: Ghadban
authors.affiliation: Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
authors.forename: Judith L
authors.initials: JL
authors.lastname: Dibbern
authors.affiliation: Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Reeh
authors.affiliation: Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
authors.forename: Jameel T
authors.initials: JT
authors.lastname: Miro
authors.affiliation: Department of Surgery, University Medical College Rostock, Schillingallee 35, 18057, Rostock, Germany.
authors.forename: Tung Y
authors.initials: TY
authors.lastname: Tsui
authors.affiliation: Clinic for Surgery, University Clinic of Schleswig-Holstein, Campus Luebeck, Ratzeburger Allee 160, 23562, Luebeck, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Wellner
authors.affiliation: Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
authors.forename: Jakob R
authors.initials: JR
authors.lastname: Izbicki
authors.affiliation: Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
authors.forename: Cenap
authors.initials: C
authors.lastname: Güngör
authors.affiliation: Department of General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany. vashist@uke.de.|Department of Visceral Surgery, Kantonsspital Aarau AG, Tellstrasse 25, 5001, Aarau, Switzerland. vashist@uke.de.
authors.forename: Yogesh K
authors.initials: YK
authors.lastname: Vashist
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy* / Q000473:pathology; D017209:Apoptosis / Q000187:drug effects; D016227:Benzoquinones / Q000494:pharmacology*; D045744:Cell Line, Tumor; D003841:Deoxycytidine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm; D004354:Drug Screening Assays, Antitumor; D005472:Fluorouracil / Q000008:administration & dosage / Q000494:pharmacology*; D018841:HSP90 Heat-Shock Proteins / Q000037:antagonists & inhibitors*; D006801:Humans; D020128:Inhibitory Concentration 50; D047029:Lactams, Macrocyclic / Q000494:pharmacology*; D058990:Molecular Targeted Therapy; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors*; D010190:Pancreatic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D012008:Recurrence; D000093542:Gemcitabine
chemical_list: C548185:17-(2-(pyrrolidin-1-yl)ethyl)-amino-17-demethoxygeldanamycin; D016227:Benzoquinones; D018841:HSP90 Heat-Shock Proteins; D047029:Lactams, Macrocyclic; D009363:Neoplasm Proteins; C448659:17-(dimethylaminoethylamino)-17-demethoxygeldanamycin; D003841:Deoxycytidine; C112765:tanespimycin; D005472:Fluorouracil; D000093542:Gemcitabine
keywords: Anti-tumor therapy; Geldanamycin; HSP90; Pancreatic cancer; Target therapy