Characterization and Application of Circulating Apoptotic Bodies in Cancer Patients

Proliferation of cancer cells usually accompanies apoptosis, which would release lots of apoptotic bodies. As the apoptotic bodies are surrounded with lipid membrane, their contents, including DNA, RNA, and proteins, are resistance to hydrolysis by external enzymes and may exist for a relatively long period. The aim of this research is to develop a method to collect apoptotic bodies, to prove that apoptotic bodies from cancer tissue exist in peripheral blood of cancer patients, and to establish the relationship of specific mRNA level and cancer development. We will take advantage of a special feature of apoptotic bodies phosphatidylserine on their outer membrane would bind to annexin V to develop the method for apoptotic body collection, using annexin V-coated magnetic beads. In the first part of this research, the apoptotic bodies originated from in vitro culture will be used for optimization of collection efficiency by magnetic beads. Then the apoptotic bodies from peripheral blood of cancer patients will tested if they contains cancer specific mRNA. If so, mRNA from patients! apoptotic bodies will be subjected to microarray analysis to measure the gene expression profile. The results from these experiments may prove that circulating apoptotic bodies can be used for diagnosis or prognosis. Until now, there is no literature describes the usage of circulating apoptotic bodies as disease markers. This project, if successful, will provide a non-invasive method to measure alteration of gene expression in disease tissues. As apoptosis is not only happens in cancer but also in other diseases linked with inflammation and tissue necrosis, circulating apoptotic bodies may also be useful for diagnostics of such diseases.

Project ID:PC9709-0950
External Project ID:NSC97-2320-B182-016-MY3