Study On The Preparation Of Genomic DNA Microarray And Its Application On Screening Tumor-Associated Genes

Cancer is one of the severe diseases that has drawn great attention. It is now known that the development of cancer undergoes a complicated multiple steps, involving alterations not only at expression level, but also at the genomic stages. Therefore, it is vitally important to study tumorigenesis from the overall genomic view of perspectives. Single genetic variations have been documented over the years of cancer research. With the advent of DNA microarray technology, groups of genes or even the whole genome could be studied simultaneously in parallel, ensuring more and more studies conducted systematically.In this research the DNA microarray technique was employed to screen the tumor specific genes present in the genome of K562 cells. The genomic DNA of normal human white blood cells (WBC) was used as control. Cells from both K562 and WBC were purified and digested with Sau3A I respectively. The digested genomic DNA fragments of K562 cells were cloned into TA cloning vector and the corresponding genomic DNA library were constructed. The genomic DNA fragments were amplified from such a library and were spotted onto slides with Cartesian 5500 Microarrayer. The digested genomic DNA fragments of WBC were labeled with fluorescent Cy3 by restriction display PCR (RD-PCR), followed by hybridizafon with the microarray. After hybridization, the slide was scanned with ScanArray Scanner. Hybridization results demonstrated that among the 426 ta 42 differential genes were identified to be specific to K562 gen sequencing verifications, the well-known breakpoint cluster genealso found this list, the rest were found to be possible regulatory elements of gene expression.In summary, the DNA microarrays thus constructed provided a novel approach for identification of genes specific to tumor cells. This approach shall be helpful in the elucidation of the mechanisms of tumorigenesis.