EBV Conference 2008 Guangzhou - Baylor College of Medicine

20 (RegID: 1132)
Qian Tao
Institution: Chinese University of Hong Kong
e-mail: qtao@clo.cuhk.edu.hk
EPIGENETIC ETIOLOGY OF NASOPHARYNGEAL CARCINOMA
Qian Tao
Oralabstract:
Carcinogenesis is a multi-step process, involving multiple genetic and epigenetic alterations including the
epigenetic disruption of tumor suppressor genes (TSGs) through promoter CpG methylation. The frequent
presence of epigenetic abnormalities in tumor cells provides us with potential epigenetic biomarkers for
molecular cancer diagnosis and also a novel way of identifying new TSGs. Using DNA methyltransferase
inhibitors as demethylation agents, epigenetic inactivation of TSGs can also be reversed and exploited as a
cancer therapeutic strategy. Using nasopharyngeal carcinoma (NPC) as a tumor model which is prevalent
in southern China, I attempted to identify epigenetically inactivated novel TSGs, by employing integrative
epigenetic/genomic approaches such as methylation subtraction, array-CGH, high-throughput expression
profiling coupled with methylation analysis, and functional studies. A few novel candidate TSGs have
been identified, including cell signaling-related and transcriptional regulatory genes. These genes are
frequently methylated and downregulated in common tumors including NPC. Functional analyses showed
that these candidate genes could induce apoptosis of tumor cells and suppress tumor cell growth, are thus
functional TSGs. The epigenetic silencing of these TSGs would disrupt normal cell signaling control and
contribute to NPC pathogenesis.
EBV Conference 2008 Guangzhou
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