[Analysis of gene expression patterns of leukemia K562 cells after cytochalasin B treatment].

Background & Objective: The advanced technique of DNA microarray makes it possible to monitor the expression of thousands of genes simultaneously in one hybridization experiment. This technique accelerates demonstration of anti-tumor drug mechanisms and discovery of new drug targets. This study was designed to investigate the differential gene expression of K562 cells after cytochalasin B treatment using cDNA microarray.

Methods: Restriction display polymerase chain reaction (RD-PCR) products of 277 human genes were spotted on a glass slide in microarray. K562 cells grew in RPMI 1640 medium with 10 microg/ml cytochalasin B. After 24 hours, the total RNA was isolated from K562 cells, and mRNA was purified. Both mRNA from the treated K562 cells and the controlled K562 cells were reversely transcribed into cDNA and labeled with two different fluorescence dyes: Cy5 or Cy3, using a method of restriction digestion and PCR labeling (RD-PCR). The probes were hybridized to the cDNA microarrays. After high-stringent washing,the cDNA microarray was scanned for the fluorescent signals and showed difference between the two cells.

Results: Among the 277 target genes, 18 down-regulated genes were identified after cytochalasin B treatment.

Conclusion: There is a consistent tendency toward lower-expressed genes in partial K562 cells after cytochalasin B treatment. Most down-regulated genes were correlated with cell proliferation, signal transduction, and transcription factor.