title: Desmoplasia and chemoresistance in pancreatic cancer.
abstract: Pancreatic ductal adenocarcinoma (PDAC) occurs mainly in people older than 50 years of age. Although great strides have been taken in treating PDAC over the past decades its incidence nearly equals its mortality rate and it was quoted as the 4th leading cause of cancer deaths in the U.S. in 2012. This review aims to focus on research models and scientific developments that help to explain the extraordinary resistance of PDAC towards current therapeutic regimens. Furthermore, it highlights the main features of drug resistance including mechanisms promoted by cancer cells or cancer stem cells (CSCs), as well as stromal cells, and the acellular components surrounding the tumor cells-known as peritumoral desmoplasia-that affects intra-tumoral drug delivery. Finally, therapeutic concepts and avenues for future research are suggested, based on the topics discussed.
authors.affiliation: Division of Gastroenterology, Endocrinology and Metabolism, University Hospital, Philipps-Universitaet Marburg, Baldingerstrasse, Marburg 35043, Germany. Marvin.Schober@med.uni-marburg.de.
authors.forename: Marvin
authors.initials: M
authors.lastname: Schober
authors.affiliation: Department of Medicine II (Department of Gastroenterology, Hepatology, and Infectious Diseases), University Medical Center Mannheim (UMM), Theodor-Kutzer-Ufer 1-3, Mannheim 68135, Germany. ralf.jesenofsky@medma.uni-heidelberg.de.
authors.forename: Ralf
authors.initials: R
authors.lastname: Jesenofsky
authors.affiliation: Department of Medicine II (Department of Gastroenterology, Hepatology, and Infectious Diseases), University Medical Center Mannheim (UMM), Theodor-Kutzer-Ufer 1-3, Mannheim 68135, Germany. ralf.faissner@web.de.
authors.forename: Ralf
authors.initials: R
authors.lastname: Faissner
authors.affiliation: Department of Medicine II (Department of Gastroenterology, Hepatology, and Infectious Diseases), University Medical Center Mannheim (UMM), Theodor-Kutzer-Ufer 1-3, Mannheim 68135, Germany. C_Weidenauer2000@yahoo.de.
authors.forename: Cornelius
authors.initials: C
authors.lastname: Weidenauer
authors.affiliation: Lung Cancer, Genomics/Epigenomics Group, Division of Epigenomics and Cancer Risk Factors, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, Heidelberg 69121, Germany. w.hagmann@dkfz-heidelberg.de.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Hagmann
authors.affiliation: Division of Gastroenterology, Endocrinology and Metabolism, University Hospital, Philipps-Universitaet Marburg, Baldingerstrasse, Marburg 35043, Germany. michlp@med.uni-marburg.de.
authors.forename: Patrick
authors.initials: P
authors.lastname: Michl
authors.affiliation: Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, SE-141 52 Huddinge, Sweden. rainer.heuchel@ki.se.
authors.forename: Rainer L
authors.initials: RL
authors.lastname: Heuchel
authors.affiliation: Gastrocentrum, Karolinska University Hospital, Stockholm, Stockholm 141 86, Sweden. stephan.haas@karolinska.se.
authors.forename: Stephan L
authors.initials: SL
authors.lastname: Haas
authors.affiliation: Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, SE-141 52 Huddinge, Sweden. stephan.haas@karolinska.se.
authors.forename: J-Matthias
authors.initials: JM
authors.lastname: Löhr