Saurabh Saha, Alberto Bardelli,* Phillip Buckhaults, Victor E. Velculescu, Carlo Rago, Brad St. Croix, Katharine E. Romans, Michael A. Choti, Christoph Lengauer, Kenneth W. Kinzler, Bert Vogelstein

To gain insights into the molecular basis for metastasis, we compared the global gene expression profile of metastatic colorectal cancer with that of primary cancers, benign colorectal tumors, and normal colorectal epithelium. Among the genes identified, the PRL-3 protein tyrosine phosphatase gene was of particular interest. It was expressed at high levels in each of 18 cancer metastases studied but at lower levels in nonmetastatic tumors and normal colorectal epithelium. In 3 of 12 metastases examined, multiple copies of the PRL-3 gene were found within a small amplicon located at chromosome 8q24.3. These data suggest that the PRL-3 gene is important for colorectal cancer metastasis and provide a new therapeutic target for these intractable lesions.

Howard Hughes Medical Institute, The Oncology Center, Department of Surgery, and
  Program in Cellular and Molecular Medicine, Johns Hopkins Medical Institutions, Baltimore, MD 21231, USA.

^* On leave from the University of Torino, Institute for Cancer Research, 10060 Candiolo, Torino, Italy.