The scale and scope of DNA sequencing has grown to where it can increasingly be used for medical applications such as diagnosing inherited diseases in children, tracking infectious outbreaks and in cancer medicine, determining inherited risk factors and informing decision making for more precise treatment. A sample of a person’s inherited, “normal” DNA can be readily obtained from white blood cells obtained via a simple blood draw. In contrast, analysis of cancer genomes requires both a normal sample for comparison, and DNA from the tumour itself, often represented by a biopsy sample. But biopsied tissues usually contain both tumour and normal cells, and if the proportion of tumour cells is too low, it can render the sample useless for DNA sequence analysis.
Drs. Marco Marra and Robin Coope of the BC Cancer Agency will implement an automated method to identify and enrich tumour cells in biopsy materials that are mixed with normal cells, thereby increasing the number of biopsies that can be used for DNA sequence analysis and making the use of sequencing more practical at the scale of population cancer care. At present, such enrichment can only be achieved with significant manual intervention and requiring pathology expertise to perform. This project is relevant to both current patients and tumour samples archived from previous cases. Large scale analysis of the latter will allow findings from genome analysis to be correlated to data collected on treatments that were employed and the ultimate outcomes for patients. These correlations, when applied to current cases, have the potential to inform on treatment options.