title: MDR1/P-glycoprotein and MRP-1 drug efflux pumps in pancreatic carcinoma.
abstract: BACKGROUND
  Pancreatic cancer is one of the most challenging solid organ malignancies. This is due to its aggressiveness, frequent late presentation as advanced disease and chemoresistance. A better understanding of the molecular basis of its drug resistance is needed.
  
  
  METHODS
  In this study, the first of its kind, the expression of both MDR1 P-gp and MRP-1 protein in pancreatic tumour specimens was examined by immunohistochemistry. Expression of these drug efflux pumps was examined using semi-quantitative immunohistochemistry according to the percentage of cells within the tumour, demonstrating another staining intencity.
  
  
  RESULTS
  Overall, 93.3% of pancreatic carcinomas expressed MDR1 P-gp, approximately 31% co-expressed MRP-1 with MDR1 P-gp, while 6.7% expressed neither of these proteins.
  
  
  CONCLUSIONS
  Our results show that drug efflux pumps, in particular that of MDR1 P-gp, are frequently expressed in pancreatic cancer. While a causative role for these efflux pumps in pancreatic cancer chemoresistance cannot necessarily be concluded, the information presented here should be considered when selecting chemotherapy/drug efflux pump inhibitors for future therapies.
authors: National Institute for Cellular Biotechnology, Dublin City University, Dublin, Ireland. Lorraine.ODriscoll@dcu.ie
authors: L
authors: L
authors: O'Driscoll
authors: N
authors: N
authors: Walsh
authors: A
authors: A
authors: Larkin
authors: J
authors: J
authors: Ballot
authors: W S
authors: WS
authors: Ooi
authors: G
authors: G
authors: Gullo
authors: R
authors: R
authors: O'Connor
authors: M
authors: M
authors: Clynes
authors: J
authors: J
authors: Crown
authors: S
authors: S
authors: Kennedy
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000096:biosynthesis / Q000378:metabolism*; D000230:Adenocarcinoma / Q000378:metabolism; D000328:Adult; D000368:Aged; D018278:Carcinoma, Neuroendocrine / Q000378:metabolism; D018281:Cholangiocarcinoma / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D027425:ATP-Binding Cassette, Sub-Family C Proteins / Q000096:biosynthesis / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000378:metabolism*
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D027425:ATP-Binding Cassette, Sub-Family C Proteins; C421109:multidrug resistance-associated protein 1