title: Autonomous inhibition of apoptosis correlates with responsiveness of colon carcinoma cell lines to ciglitazone.
abstract: Colorectal cancer is a leading cause of mortality worldwide. Resistance to therapy is common and often results in patients succumbing to the disease. The mechanisms of resistance are poorly understood. Cells basically have two possibilities to survive a treatment with potentially apoptosis-inducing substances. They can make use of their existing proteins to counteract the induced reactions or quickly upregulate protective factors to evade the apoptotic signal. To identify protein patterns involved in resistance to apoptosis, we studied two colorectal adenocarcinoma cell lines with different growth responses to low-molar concentrations of the thiazolidinedione Ciglitazone: HT29 cells underwent apoptosis, whereas SW480 cells increased cell number. Fluorescence detection and autoradiography scans of 2D-PAGE gels were performed in both cell lines to assess protein synthesis and turnover, respectively. To verify the data we performed shotgun analysis using the same treatment procedure as in 2D-experiments. Biological functions of the identified proteins were mainly associated with apoptosis regulation, chaperoning, intrinsic inflammation, and DNA repair. The present study suggests that different growth response of two colorectal carcinoma cell lines after treatment with Ciglitazone results from cell-specific protein synthesis and differences in protein regulation.
authors.affiliation: Department of Medicine I, Clinic for Internal Medicine I, Institute of Cancer Research, Medical University of Vienna, Vienna, Austria; Department of Anesthesia, General Intensive Care, and Pain Management Medical, Medical University of Vienna, Vienna, Austria.
authors.forename: David M
authors.initials: DM
authors.lastname: Baron
authors.affiliation: Department of Medicine I, Clinic for Internal Medicine I, Institute of Cancer Research, Medical University of Vienna, Vienna, Austria.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Kaindl
authors.affiliation: Institute of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria.
authors.forename: Verena J
authors.initials: VJ
authors.lastname: Haudek-Prinz
authors.affiliation: Department of Medicine I, Clinic for Internal Medicine I, Institute of Cancer Research, Medical University of Vienna, Vienna, Austria.
authors.forename: Editha
authors.initials: E
authors.lastname: Bayer
authors.affiliation: Department of Medicine I, Clinic for Internal Medicine I, Institute of Cancer Research, Medical University of Vienna, Vienna, Austria.
authors.forename: Clemens
authors.initials: C
authors.lastname: Röhrl
authors.affiliation: Institute of Analytical Chemistry, Faculty of Chemistry, University of Vienna, Vienna, Austria.
authors.forename: Christopher
authors.initials: C
authors.lastname: Gerner
authors.affiliation: Department of Medicine I, Clinic for Internal Medicine I, Institute of Cancer Research, Medical University of Vienna, Vienna, Austria.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Marian
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D002453:Cell Cycle / Q000187:drug effects; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D015179:Colorectal Neoplasms / Q000473:pathology*; D006801:Humans; D047495:PPAR gamma / Q000819:agonists; D014176:Protein Biosynthesis / Q000187:drug effects; D045162:Thiazolidinediones / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D047495:PPAR gamma; D045162:Thiazolidinediones; C039671:ciglitazone