Institute of Pharmacology of Natural Products and Clinical PharmacologyProf Dr. Thomas SimmetInhibition Akt by Tetracyclic Triterpenoids Induces Cell Cycle Arrest and Apoptosis in Prostate Cancer CellsDissertation presented to the Medical Faculty of the Ulm University to obtain the degree Doctor of Human Biology Aidee Constanza Estradafrom Cali, Colombia2007 Amtierender Dekan: Prof. Dr. Klaus-Michael Debatin 1. Berichterstatter: Prof. Dr. Thomas Simmet 2. Berichterstatter: Prof. Dr. Christian Beltinger Tag der Promotion: 18.02.2009 2 This Dissertation was submitted at the Ulm University to the represent of the academic administration of Medical Faculty: Mr. Dean Prof. Dr. Klaus-Michael Debatin.Also had the advice of following examinators: PD Dr. Barbara Möpps, Apl. Prof. Dr. Christian Beltinger and PD Dr. Rainer KüferOn February 18 2007, the presentation of this dissertation was subject to assessment by the jury in Ulm. Successfully obtaining the title granted by the Medical Faculty as Dr. in Human Biology.341. Introduction 101.1. Cancer 101.2.