Capillary electrophoresis in analysis of DNA variations in rectal cancer.

Abstract

For colorectal cancer surgery is the main and most efficient treatment. In spite of this many patients later suffer from metastases or tumour recurrence. One cause may be peritoneal dissemination of free cancer cells exfoliated from the serosa surfaces of primary cancers. <br> We have developed and validated a denaturing capillary electrophoresis (DCE) method that is very sensitive in detecting mutation. The DCE method is simple, with only a two-step protocol PCR and electrophoresis. The method is now high throughput with the convertion to commercially automated single and multicapillary instruments. <br> We used this method to detect mutations in the k-ras gene with DNA from cells obtained by lavage. Patients with k-ras mutated cells in the lavage immediately after surgery have a reduced life expectation. Detection of exfoliated cells in the abdominal cavity may be a useful diagnostic tool to improve the staging and eventually characterize patients whom could benefit from aggressive multimodal treatment of rectal cancer. We have also applied the DCE method to detect selected DNA variations important in the adenoma-carcinoma sequence and in pharmacogenomic aspects of rectal cancer patients.