Differential Expressions of Genes in Colorectal Cancer with Liver Metastasis by using a cDNA Microarray Chip: A Pilot Study

ABSTRACT

PURPOSE: Liver metastasis is the most common type of failure in the treatment of colorectal cancer. The identification of differential expressions of genes in colorectal cancer and liver metastasis is important to differentiate the genetic mechanism of carcinogenesis and liver metastasis from that of a normal mucosa. The aim of this study is to find candidate genes playing roles in liver metastasis of colorectal cancer by using cDNA microarray. METHODS: We screened a group of genes differentially expressed in a normal mucosa and in cancer and liver metastasis by using a 4.7 K cDNA microarray chip in 8 patients with far advanced colorectal cancer from Jan 2003 to May 2004 at Kyungpook National University Hospital. RESULTS: A comparison of mRNA expressions of genes in normal mucosa vs. cancer, normal mucosa vs. liver metastasis, and cancer vs. liver metastasis, 76 and 27 known and unknown genes were significantly over-expressed in cancer and liver metastasis, respectively. Also 62 and 26 genes were down- regulated in cancer and liver metastasis. Among those genes, TIMP-1, SRY-box9, Rattus norvegicus fibronectin 1, mitotic check point regulator, etc. were constantly up- regulated in cancer or metastasis, and hsgk, etc. were down-regulated in cancer or liver metastasis. CONSLUSIONS The cDNA microarray chip technique could be a useful for robust screening of candidate genes involved in carcinogenesis or metastasis of colorectal cancer.