Multidrug resistance in human neuroblastoma cells.
Neuroblastoma remains a significant problem in pediatric oncology. Recently a "multidrug-resistance" gene that may cause cells to become resistant to various chemotherapeutic agents has been cloned. The gene encodes the high-molecular-weight plasma membrane protein known as P-glycoprotein. To study the expression of this gene in cells exhibiting the multidrug-resistant phenotype, a panel of sublines selected with several different natural product drugs was established. The drug-sensitive parental BE(2)-C cells were clonally isolated from the human neuroblastoma SK-N-BE(2) line and exhibit a 150-fold increase in the copy number of the N-myc protooncogene. Sublines were selected by stepwise increases in the concentration of actinomycin-D, doxorubicin, vincristine, or colchicine. Gene amplification was assessed using Southern analysis, and RNA levels were determined by Northern and dot-blot analysis. Western blotting was used to determine protein levels. N-myc amplification and expression were simultaneously determined to assess possible alterations associated with development of multidrug resistance. Amplified P-glycoprotein-encoding genes were not seen in control lines but were clearly present in those that had undergone exposure to each of the chemical agents. Similarly, steady-state messenger RNA and protein levels were greatly increased in the drug-resistant sublines. We conclude that human neuroblastoma cells can acquire the multidrug-resistant phenotype after exposure to various chemotherapeutic agents.
LaQuaglia
M P
MP
Department of Surgery, Memorial Sloan-Kettering Cancer Center, New York, NY 10021.
Kopp
E B
EB
Spengler
B A
BA
Meyers
M B
MB
Biedler
J L
JL
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents / Q000494:pharmacology*; D002460:Cell Line; D003078:Colchicine / Q000494:pharmacology; D004273:DNA, Neoplasm / Q000032:analysis; D003609:Dactinomycin / Q000494:pharmacology; D004317:Doxorubicin / Q000494:pharmacology; D004351:Drug Resistance / Q000235:genetics; D005784:Gene Amplification; D006801:Humans; D015151:Immunoblotting; D008562:Membrane Glycoproteins / Q000235:genetics; D009363:Neoplasm Proteins / Q000235:genetics; D009447:Neuroblastoma / Q000235:genetics / Q000473:pathology*; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics; D012334:RNA, Neoplasm / Q000032:analysis; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000473:pathology; D014750:Vincristine / Q000494:pharmacology
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D004273:DNA, Neoplasm; D008562:Membrane Glycoproteins; D009363:Neoplasm Proteins; D016271:Proto-Oncogene Proteins c-myc; D012334:RNA, Neoplasm; D003609:Dactinomycin; D014750:Vincristine; D004317:Doxorubicin; D003078:Colchicine