Diverse gene expression pattern during 5-fluorouridine-induced apoptosis.
The purpose of this study was to establish experimental conditions to produce apoptosis by the fluorinated pyrimidine 5-fluorouridine and to examine the changes in gene expression that occurred during cell death. HCT-116 colorectal carcinoma cells were exposed to 10 microM 5-fluorouridine alone or in the presence of 1 mM uridine, 30 microM thymidine or both uridine and thymidine. A time-dependent increase in the percentage of apoptotic cells and a decrease in the percentage of viable cells were observed when the cells were treated with 5-fluorouridine in the absence of uridine (p < 0.001) but not in the presence of uridine. cDNA microarray analysis was used to study the expression of 1,200 different genes during apoptosis by 5-flurouridine. The expression of 33 genes was upregulated by 5-fold or greater at 16 and 24 h of 5-fluorouridine exposure. The largest cluster of upregulated genes included a group of genes classified as growth factors, cytokines and chemokines (e.g. interleukin-3, interleukin-4, B-cell growth factor 1 and stem cell growth factor). The expression of MIC-1 increased up to 100-fold during 5-flurouridine exposure. One hundred and twenty-four genes were downregulated by 5-fold or greater following exposure to 5-fluorouridine. The downregulated genes were distributed throughout the six different classifications on the array. Our data demonstrate a diverse pattern of gene expression during the fluorouridine-induced apoptosis and suggest that mechanisms besides a global inhibition of RNA synthesis/ processing contribute to the RNA-directed cytotoxicity of fluoropyrimidines.
Schmittgen
Thomas D
TD
College of Pharmacy, Ohio State University, L.M. Parks Hall, Columbus, OH 43210, USA. schmittgen.2@osu.edu
Gissel
Kari A
KA
Zakrajsek
Brian A
BA
Lawrence
B Paige
BP
Liu
Qian
Q
Jupe
Eldon R
ER
Lerner
Megan R
MR
Do
Son V
SV
Brackett
Daniel J
DJ
D000704:Analysis of Variance; D017209:Apoptosis / Q000187:drug effects* / Q000235:genetics; D002470:Cell Survival / Q000187:drug effects; D016000:Cluster Analysis; D015179:Colorectal Neoplasms / Q000235:genetics / Q000473:pathology / Q000648:ultrastructure; D005434:Flow Cytometry; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects / Q000235:genetics; D045325:HCT116 Cells; D006801:Humans; D008854:Microscopy, Electron; D009336:Necrosis; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D012334:RNA, Neoplasm / Q000235:genetics / Q000378:metabolism; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D013936:Thymidine / Q000494:pharmacology; D013997:Time Factors; D015854:Up-Regulation / Q000187:drug effects / Q000235:genetics; D014529:Uridine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology
D012334:RNA, Neoplasm; C001943:5-fluorouridine; D013936:Thymidine; D014529:Uridine