title: Induction of chemoresistance in a cultured canine cell line by retroviral transduction of the canine multidrug resistance 1 gene.
abstract: OBJECTIVE
  To induce chemoresistance in a normal canine cell line through the transduction of the canine multidrug resistance 1 gene (mdr1).
  
  
  METHODS
  Madin-Darby canine kidney (MDCK) epithelial cell line.
  
  
  METHODS
  The full-length canine mdr1 cDNA clone isolated in our laboratory was inserted into a Moloney murine leukemia virus-based vector to construct the retroviral vector, pLNC-cMDR1. After retroviral transduction of pLNC-cMDR1 into MDCK cells, the expression and function of the P-glycoprotein, a product of mdr1, were assessed by immunoblotting, measurement of rhodamine123 (Rh123) retention, and drug sensitivity assays.
  
  
  RESULTS
  P-glycoprotein was strongly expressed in cells transduced with pLNC-cMDR1. This P-glycoprotein was fully functional, as demonstrated by the decreased Rh123 retention and the increased resistance to chemotherapeutic drugs. Measured as 50% inhibitory concentrations, resistance increased 59 times to vincristine and 25 times to doxorubicin in MDCK cells after transduction of pLNC-cMDR1.
  
  
  CONCLUSIONS
  Transduction of canine mdr1 is an effective method for inducing chemoresistance in normal canine cells. This system may be applicable to the induction of drug resistance in hematopoietic cells.
authors.affiliation: Department of Veterinary Internal Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan.
authors.forename: Shinobu
authors.initials: S
authors.lastname: Matsuura
authors.forename: Hisao
authors.initials: H
authors.lastname: Koto
authors.forename: Kaori
authors.initials: K
authors.lastname: Ide
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Fujino
authors.forename: Asuka
authors.initials: A
authors.lastname: Setoguchi-Mukai
authors.forename: Koichi
authors.initials: K
authors.lastname: Ohno
authors.forename: Hajime
authors.initials: H
authors.lastname: Tsujimoto
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D001483:Base Sequence; D019556:COS Cells; D002460:Cell Line; D002522:Chlorocebus aethiops; D018076:DNA, Complementary / Q000235:genetics; D004285:Dogs / Q000235:genetics* / Q000378:metabolism; D004317:Doxorubicin / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm; D005434:Flow Cytometry / Q000662:veterinary; D005456:Fluorescent Dyes / Q000378:metabolism; D005822:Genetic Vectors / Q000235:genetics; D020128:Inhibitory Concentration 50; D008969:Molecular Sequence Data; D012190:Retroviridae / Q000235:genetics*; D020112:Rhodamine 123 / Q000378:metabolism; D017422:Sequence Analysis, DNA; D014161:Transduction, Genetic / Q000662:veterinary*; D014750:Vincristine / Q000494:pharmacology
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D018076:DNA, Complementary; D005456:Fluorescent Dyes; D020112:Rhodamine 123; D014750:Vincristine; D004317:Doxorubicin