Multiple pathways are involved in drug resistance to doxorubicin in an osteosarcoma cell line.
Drug resistance continues to be a stumbling block in achieving a better cure rate in several cancers, including osteosarcoma. To understand this, we developed a doxorubicin drug-resistant osteosarcoma cell line (143B-DR-DOX). This cell line had an IC50 of 75 micromol/l compared with the parental 143B cell line's IC50 of 0.4 micromol/l. Using a 22000 70-mer oligomicroarray, gene expression studies were performed in four replicates. Data analysis was done using the TIGR Microarray suite. Seventy-four genes were found to be either upregulated (21) or downregulated (53). Real time quantitative-PCR was done on 21 genes, which confirmed the gene expression data for 11 genes. Choosing the significant fold change criteria of greater than 2-fold upregulation or downregulation, four genes including multidrug resistance 1, interleukin-8, Krüppel-like factor 2 and MGC4175 were found to be upregulated and seven genes including epidermal growth factor receptor-coamplified and overexpressed protein, uridine phosphorylase 1, a disintegrin and metalloproteinase domain 19, cytochrome C1, SEC, S-adenosyl homocysteine hydrolase and p53 were found to be downregulated. The data suggest that apart from the known gene alterations in doxorubicin resistance (multidrug resistance 1, topoisomerase IIbeta), others can also contribute to the drug-resistance phenotype. The involvement of interleukin-8 and Krüppel-like factor 2 suggests that the peroxisome proliferator-activated receptors gamma pathway may also be involved in doxorubicin drug resistance in the 143B-DR-DOX cell line.
Rajkumar
Thangarajan
T
Department of Molecular Oncology, Cancer Institute (WIA), Adyar, Chennai 600020, India. rajkumart@yahoo.com
Yamuna
Manoharan
M
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000187:drug effects / Q000235:genetics; D000903:Antibiotics, Antineoplastic / Q000008:administration & dosage / Q000494:pharmacology*; D045744:Cell Line, Tumor; D004250:DNA Topoisomerases, Type II / Q000187:drug effects / Q000235:genetics; D004268:DNA-Binding Proteins / Q000187:drug effects / Q000235:genetics; D004317:Doxorubicin / Q000008:administration & dosage / Q000494:pharmacology*; D019008:Drug Resistance, Neoplasm; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D020128:Inhibitory Concentration 50; D016209:Interleukin-8 / Q000187:drug effects / Q000235:genetics; D051741:Kruppel-Like Transcription Factors / Q000187:drug effects / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D012516:Osteosarcoma / Q000188:drug therapy*; D047495:PPAR gamma / Q000187:drug effects / Q000378:metabolism; D016133:Polymerase Chain Reaction
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000903:Antibiotics, Antineoplastic; D004268:DNA-Binding Proteins; D016209:Interleukin-8; C096161:KLF2 protein, human; D051741:Kruppel-Like Transcription Factors; D047495:PPAR gamma; D004317:Doxorubicin; D004250:DNA Topoisomerases, Type II