The Second International Symposium on Circulating Nucleic Acids in Plasma and Serum (CNAPS-2) held in conjunction with the 6th Annual Scientific Symposium of the Hong Kong Cancer Institute Hong Kong February 20–21, 2001

Tumor–derived genetic alterations in plasma and serum P. Anker Plant Biochemistry and Physiology, Faculty of Science, University of Geneva, Switzerland Small amounts of free DNA circulate in both healthy and diseased human plasma/serum, and increased concentrations of DNA are present in the plasma of cancer patients. Characteristics of tumor DNA have been found in genetic material extracted from the plasma of cancer patients. These features include decreased strand stability, mutations of specific oncogenes or tumor suppressor genes, gene rearrangements and amplifications, microsatellite alterations and hypermethylation of several genes. Moreover, free viral DNA such as EBV has been detected circulating in the plasma. Finally, mRNA characteristic of tumor cells has also been found in the serum of cancer patients. Malignancies studied include breast, colorectal, pancreatic cancer, head and neck, lung, kidney, breast, ovarian, bladder, nasopharyngeal, liver cancer, non-Hodgkin’s lymphoma, acute B cell leukemia and melanoma. The results obtained, sometimes prior to clinical diagnosis, have opened a new research area indicating that plasma DNA might eventually be a suitable target for the development of non-invasive diagnostic, prognostic and follow-up tests for cancer.