AIM:To investigate the construction of oligonucleotide microarray specialized for pancreatic adenocarcinoma-associated genes and its preliminary application of detecting differential expressed genes in pancreatic cancer.METHODS:Pancreatic cancer related genes were purposely selected,and oligonucleotide microarray was prepared by spotting oligonucleotide probes on glass slides coated with APS-PDC.Labeled cDNA targets for hybridizations were synthesized by reverse transcription from total RNA in the presence of Cy5-dCTP and Cy3-dCTP,respectively.Hybridized microarray was scanned by Agilent laser scanner,and the aquired image was analyzed by Imagene3.0 software.The intensity ratios of Cy3 and Cy5 were calculated.To confirm the expression profiles of these genes,quantitative reverse transcription-PCR (QRT-PCR) was carried out for CDC25B and TUSC3 genes,and β-actin gene was taken as internal control.The product of PCR was quantitated by comparative Ct method.RESULTS:The signal of microarray hybridization was clear,and the images had a lower background and higher signal-noise ratio.In comparison with normal pancreas,twenty -four differentially expressed genes were identified which included seventeen up-regulated and seven down-regulated genes.The results of QRT-PCR demonstrated that the expressions of CDC25B and TUSC3 in pancreatic cancer were up-regulated and down-regulated respectively,which is consistent with microarray results.CONCLUSION:The oligonucleotide microarray specialized for pancreatic cancer is desirable for its specialty and sensitivity,which can simultaneously and parallelly detect multiple pancreatic cancer-associated genes.