Objective: To detect the differentially expressed genes in human polycystic kidney by cDNA microarray.
Methods: The PCR products of 8398 genes were spotted onto a chip in array. Both mRNAs isolated from polycystic kidney tissue and normal kidney tissue were reversely transcribed to cDNAs with the incorporation of fluorescent dUTP (Cy5-dUTP and Cy3-dUTP) for preparing the hybridization probes. The mixed probes were hybridized to the cDNA microarray. Then the cDNA microarray was scanned for the fluorescent signals and the display of differences between the 2 tissues. IGF1 mRNA, one of the up regulated genes was detected by in situ hybridization technique in the two tissues to validate the result from cDNA microarray.
Results: The result indicated that the expressions of 263 genes were up regulated while the expressions of 94 genes were down regulated in the polycystic kidney tissue among the 8398 target genes. Bioinformatical analysis of those genes had been performed. The up-regulated genes were mainly the ones of oncogene, cellular skeleton and movement, apoptosis related protein, cell signal transduction protein, and cytokine. The down regulated genes were mainly the ones of anti-oncogene, DNA binding and transcription factors, cell signal transduction protein, and metabolism protein. The IGF1 mRNA expression detected by in situ hybridization was consequently consistent with the cDNA microarray.
Conclusion: cDNA microarray is an effective and quick method for studying differential expressed genes. Three hundred and fifty-seven differentially expressed genes with different functions were revealed in the polycystic kidney tissue, which may play some roles in the progression of polycystic kidney.