title: 3D pancreatic carcinoma spheroids induce a matrix-rich, chemoresistant phenotype offering a better model for drug testing.
abstract: BACKGROUND
  Pancreatic ductal adenocarcinoma (PDAC) is the fourth most common cause of cancer related death. It is lethal in nearly all patients, due to an almost complete chemoresistance. Most if not all drugs that pass preclinical tests successfully, fail miserably in the patient. This raises the question whether traditional 2D cell culture is the correct tool for drug screening. The objective of this study is to develop a simple, high-throughput 3D model of human PDAC cell lines, and to explore mechanisms underlying the transition from 2D to 3D that might be responsible for chemoresistance.
  
  
  METHODS
  Several established human PDAC and a KPC mouse cell lines were tested, whereby Panc-1 was studied in more detail. 3D spheroid formation was facilitated with methylcellulose. Spheroids were studied morphologically, electron microscopically and by qRT-PCR for selected matrix genes, related factors and miRNA. Metabolic studies were performed, and a panel of novel drugs was tested against gemcitabine.
  
  
  RESULTS
  Comparing 3D to 2D cell culture, matrix proteins were significantly increased as were lumican, SNED1, DARP32, and miR-146a. Cell metabolism in 3D was shifted towards glycolysis. All drugs tested were less effective in 3D, except for allicin, MT100 and AX, which demonstrated effect.
  
  
  CONCLUSIONS
  We developed a high-throughput 3D cell culture drug screening system for pancreatic cancer, which displays a strongly increased chemoresistance. Features associated to the 3D cell model are increased expression of matrix proteins and miRNA as well as stromal markers such as PPP1R1B and SNED1. This is supporting the concept of cell adhesion mediated drug resistance.
authors: CLINTEC, Karolinska Institutet, Stockholm 14186, Sweden.
authors: Paola
authors: P
authors: Longati
authors: Xiaohui
authors: X
authors: Jia
authors: Johannes
authors: J
authors: Eimer
authors: Annika
authors: A
authors: Wagman
authors: Michael-Robin
authors: MR
authors: Witt
authors: Stefan
authors: S
authors: Rehnmark
authors: Caroline
authors: C
authors: Verbeke
authors: Rune
authors: R
authors: Toftgård
authors: Matthias
authors: M
authors: Löhr
authors: Rainer L
authors: RL
authors: Heuchel
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology* / Q000633:toxicity; D021441:Carcinoma, Pancreatic Ductal / Q000235:genetics* / Q000378:metabolism; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D004354:Drug Screening Assays, Antitumor; D004734:Energy Metabolism; D016326:Extracellular Matrix Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D019344:Lactic Acid / Q000378:metabolism; D051379:Mice; D010190:Pancreatic Neoplasms / Q000235:genetics* / Q000378:metabolism; D010641:Phenotype; D018874:Spheroids, Cellular / Q000187:drug effects*; D014407:Tumor Cells, Cultured
chemical_list: D000970:Antineoplastic Agents; D016326:Extracellular Matrix Proteins; D019344:Lactic Acid