Researchers at the University of California, San Diego have used a new strategy to identify differences between non-metastatic and highly metastatic breast cancer cells. The article by Valerie Montel et al., “Expression profiling of primary tumors and matched lymphatic and lung metastases in a xenogeneic breast cancer model,” appears in the May 2005 issue of The American Journal of Pathology and is accompanied by a commentary. The significance of the study’s findings lies in how the microarray method was employed. Previous studies have examined the patterns of genes that are active in primary human tumors, but the genetic differences that exist between individual patients can make interpretation of such results difficult. The beauty of the Montel et al. study is the use of microarrays to analyze variations in gene activity between cancer cell lines with differing capability to spread to distant organs (metastasize) but derived from the same human breast cancer. This eliminates the problem of irrelevant genetic variability among tumors derived from different patients.
