Genetic modification of haematopoietic cells for combined resistance to podophyllotoxins, other agents covered by MDR1-mediated efflux activity and nitrosoureas.
Genetic transfer and expression of drug-resistance functions into haematopoietic stem and progenitor cells is a promising means to overcome both the acute and longterm side-effects of cytotoxic drugs in bone marrow. Here, we describe a functional analysis of a retroviral vector that co-expresses human cDNAs for multidrug resistance 1/P-glycoprotein (MDR1) and a double mutant of O(6)-alkylguanine-alkyltransferase (hATPA/GA) to high levels. The hATPA/GA protein contains two amino acid substitutions that render it resistant to compounds such as O(6)-benzylguanine that inhibit the wild-type protein which is often overexpressed in resistant tumour cells. Evidence for simultaneous drug resistance of genetically modified primary murine progenitor cells to colchicine or the podophyllotoxin etoposide, both covered by MDR1-mediated efflux activity, and the nitrosourea BCNU, which is counteracted by hATPA/GA, is presented using in vitro colony assays.
Baum
C
C
Heinrich-Pette-Institut für Experimentelle Virologie und Immunologie, Hamburg, Germany.
Peinert
S
S
Carpinteiro
A
A
Eckert
H G
HG
Fairbairn
L J
LJ
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000235:genetics*; D000818:Animals; D018906:Antineoplastic Agents, Alkylating / Q000009:adverse effects; D002330:Carmustine / Q000009:adverse effects; D018432:Drug Resistance, Multiple / Q000235:genetics; D019450:Genes, MDR; D005822:Genetic Vectors; D018380:Hematopoietic Stem Cell Transplantation; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D006801:Humans; D051379:Mice; D009607:Nitrosourea Compounds / Q000009:adverse effects; D019853:O(6)-Methylguanine-DNA Methyltransferase / Q000235:genetics; D011034:Podophyllotoxin / Q000009:adverse effects; D014161:Transduction, Genetic
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D018906:Antineoplastic Agents, Alkylating; D009607:Nitrosourea Compounds; D019853:O(6)-Methylguanine-DNA Methyltransferase; D011034:Podophyllotoxin; D002330:Carmustine