Analysis of gene expression profile of pancreatic carcinoma using cDNA microarray

AIM:To identify new diagnostic markers and drug targets,the gene expression profiles of pancreatic cancer werecompared with that of adjacent normal tissues utilizing cDNAmicroarray analysis.METHODS:cDNA probes were prepared by labeling mRNAfrom samples of six pancreatic carcinoma tissues with Cy5-dUTP and mRNA from adjacent normal tissues with Cy3-dUTP respectively through reverse transcription.The mixedprobes of each sample were then hybridized with 12 800cDNA arrays (12 648 unique human cDNA sequences),andthe fluorescent signals were scanned by ScanArray 3 000scanner (General Scanning,Inc.).The values of Cy5-dUTPand Cy3-dUTP on each spot were analyzed and calculatedby ImaGene 3.0 software (BioDiscovery,Inc.).Differentiallyexpressed genes were screened according to the criterionthat the absolute value of natural logarithm of the ratio ofCy5-dUTP to Cy3-dUTP was greater-than 0.69.RESULTS:Among 6 samples investigated,301 genes,whichaccounted for 2.38% of genes on the microarry slides,exhibited differentially expression at least in 5.There were166 over-expressed genes including 136 having beenregistered in Genebank,and 135 under-expressed genesincluding 79 in Genebank in cancerous tissues.CONCLUSION:Microarray analysis may provide invaluableinformation on disease pathology,progression,resistanceto treatment,and response to cellular microenvironmentsof pancreatic carcinoma and ultimately may lead to improvingearly diagnosis and discovering innovative therapeuticapproaches for cancer.