Predicting the Radiosensitivity of the Tumor Cells Obtained via Nasopharyngeal Swab and the Status of Dna Methylation in the Plasma from the Npc Patients, and the Relation with Local Recurrence, Metastases, and Prognosis

Distant metastasis and local recurrence account for the main causes of death in the patients with nasopharyngeal carcinoma (NPC), resulting in that approximately one third of NPC patients would die from relapse and/or distant dissemination. There have been several reports suggesting that the genes which are associated with signal transduction related to LMP-1 of EBV play an important role in radiosensitivity, local recurrence and distant metastases in NPC. This study is endeavored to examine whether there are any associations of these genes related to the prognosis of NPC patients. The first year experiment will be undertaken in a way of a cytopathological study via nasopharyngeal tumor swabs to investigate whether there is any association between the candidate genes we are interested and the survival of NPC patients. It has been demonstrated that some kinds of circulating tumor-derived DNA have the potential of providing prognostic and predictive values in various types of malignancies. Their concentrations in blood are generally higher in cancer patients than in normal subjects. After there is some evidence that the methylation status of those genes is related to the survival in NPC patients, another experiment will be attempted on the epigenetic alterations specific to plasma DNA in the NPC patients with extensive disease. The last year research will be carried out to validate those methylated genes which are shown to have prognostic values in our current study by another group of NPC patients enrolled in the previous study which have been followed up for a minimum of five years We do hope to construct a prediction model to identify the patients who are at a significant higher risk for developing distant metastasis or local recurrence. Thus it is essential that a prompt administration of intensified chemotherapy or dose-escalated radiotherapy should be provided for such higher risk patients in order to prevent the occurrence of local recurrence or distant metastasis which is usually fatal at last.

Project ID:PC10001-0079
External Project ID:NSC98-2314-B182-037-MY3