Objective: To quantitatively detect the methylation of E-cadherin gene 5'-CpG islands in acute leukemia by microarray-based DNA analysis and to briefly discuss the role of microarry for detection of methylation in tumors.
Methods: Bisulfite-modified DNA was used as a template for PCR amplification, resulting in conversion of unmethylated cytosine, but not methylated cytosine, into thymine within CpG islands of interest. Five sets of oligonucleotide probes were designed to fabricate a DNA microarray to detect the methylation changes of E-cadherin gene CpG islands in acute leukemia. By drawing a standard curve to assess the levels of changes in methylation detected in the examined samples.
Results: Microarray assay was successfully used to quantitatively detect methylation changes of E-cadherin gene in 5 acute leukemia samples. Varying degree of methylation was detected in five regions and the hypermethylation region was the same. The result was validated by gene sequencing.
Conclusion: Microarray assay may be applied as an useful tool for mapping methylation changes in multiple CpG loci and for leukemia research. It is more time-saving and labor-saving than gene sequencing and can be used to quantitatively detect changes in methylation with high throughput.