Induction of chemoresistance in a cultured canine cell line by retroviral transduction of the canine multidrug resistance 1 gene.
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.
Matsuura
Shinobu
S
Department of Veterinary Internal Medicine, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo 113-8657, Japan.
Koto
Hisao
H
Ide
Kaori
K
Fujino
Yasuhito
Y
Setoguchi-Mukai
Asuka
A
Ohno
Koichi
K
Tsujimoto
Hajime
H
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
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