Gene expression profile of human colorectal carcinoma

Despite steady progress in the diagnosis and treatment of colorectal cancer (CRC), overall therapeutic outcomes remain unsatisfactory. Therefore, a better understanding of the molecular mechanisms of CRC is urgently needed. Fourteen pairs of cancerous and matched non-cancerous tissues (at least 5 cm away) were obtained from CRC patients undergoing surgical resection. Affymetrix human GeneChip primeview array was conducted to identify differentially expressed genes (DEGs) between CRC tissues and matched adjacent normal tissues. cDNA microarray analysis of cancerous and paired noncancerous tissues from CRC patients revealed 1,868 DEGs, of which 778 in primary lesions were up-regulated and 1,090 were down-regulated. Samples from fourteen colorectal cancer patients who had undergone surgical resection of colorectal cancer were collected. No patients had received radio- or chemotherapy prior to surgery. To identify molecular signatures of CRC, we examined the DEGs in fourteen pairs of CRC primary lesions and non-cancerous surrounding tissue.