Copy Number Analysis to Determine Metastatic Genetic Alterations in Colorectal Cancer Samples

Colorectal cancer (CRC) is one of the most frequently diagnosed cancers in women and men.  It is often treatable if caught early.  However, tumors may metastasize which can result in a poor prognosis.  A better understanding of the biogenesis and evolution of metastatic tumors in colon cancer patients could lead to earlier diagnosis, pre-emptive screening, and a better outcome.   Copy number analysis of primary tumor tissue has revealed genes associated with colon cancers, but a comparison between primary and metastatic tumors has never been done. Normal tissue, primary tumor tissue, and metastatic tumor tissue was collected from twenty-five individuals.  Copy number alterations were determined by microarray data generated from Affymetrix using Molecular Inversion Probe (MIP) techniques for copy number analysis using Nexus software.  Metastatic tumor samples show a greater rate of copy number variation (CNV) from the primary tumors and even more variation from normal tissue samples.  Certain regions of the metastatic genome show high rates of CNV whereas the primary tumor genome does not.   These areas are key regions for potential understanding into the biogenesis of metastatic tumors.  Understanding specific regions and genes that have CNV in metastatic tumor samples may lead to further research in cancer genetics and possible target areas for pharmaceutical testing.