口腔癌是全球常見癌症的第六名，更是我國男性惡性癌症中排名第四名的癌症，平均死亡年齡為54歲，其造成的主因與吸菸、喝酒、嚼檳榔的習慣具有關連性。經統計顯示，早期診斷治療能有效提高患者的存活率。目前的篩檢方式是以目視或觸診，其診斷結果的準確性不高，而準確性較高的組織切片檢查，則是需進行手術侵入式檢測。近幾年，隨著次世代定序的發展，已有研究指出，其表觀基因體修飾DNA甲基化與口腔癌的腫瘤生成，造成癌症相關。因此， DNA甲基化有可能可以做為早期檢測口腔癌的生物標記。TNFRSF10C基因是細胞凋亡誘導配體誘導型受體的一種，在許多癌症中其啟動子的CG島呈現高度甲基化，如大腸癌、肺癌、前列腺癌等等[1]。故本研究想了解在口腔癌中TNFRSF10C基因的 DNA甲基化狀態與口腔癌之關係。利用焦磷酸定序技術去偵測分析其基因在口腔癌細胞株與病人組織檢體中甲基化的情形。其結果顯示，在口腔癌細胞株中，TNFRSF10C基因甲基化程度不一，且其mRNA與蛋白質的表現，受到DNA甲基化程度影響。在口腔癌及癌前病變的病人組織檢體中，則觀察到正常組織檢體的甲基化現象比癌化組織的檢體甲基化現象明顯較高。因此推論在口腔癌中TNFRSF10C基因甲基化降低可能是參與口腔癌癌化過程，使基因扮演致癌基因的角色。

oral cancer is the sixth most common cancer in worldwide. In Taiwan, it is also the fourth common of male malignant disease. Recently, with the development of next generation sequencing, the dysregulation of gene expression is a frequent occurrence in oral cancer, and the epigenetic modifications of aberrant DNA methylation in oral cancer tumorigenesis have been revealed. Therefore, the pyrosequencing assay was used to evaluate the significance of methylation level in oral cancer cell lines and patient’ tissue samples. The different methylation status of TNFRSF10C gene in oral cancer cell lines were revealed, and related to the expression of mRNA level. We analyzed the patients’ tissue samples, and found the normal tissue samples methylation level was higher than the cancer tissue samples with statistically significant difference. We conclude that the hypermethylation of TNFRSF10C gene in oral cancer cell line could induce low expression of TNFRSF10C. In clinical samples, the methylation level of the normal oral mucosa tissue was higher oral cancer. These results suggested that TNFRSF10C gene might be the oncogene in oral cancer carcinogenesis.

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