頭頸癌是常見的惡性腫瘤之一，且是全世界男性惡性腫瘤排名第六的癌症◦這些惡性腫瘤包括鼻腔、口腔、鼻竇、咽喉和下咽上皮所產生的腫瘤。口腔癌是頭頸部最常見的癌症，而其中以鱗狀細胞癌為最常見，佔口腔所有惡性腫瘤約90%。口腔鱗狀細胞癌主要危險因素為嚼食檳榔、吸煙，喝酒、紫外線照射和HPV感染。口腔癌早期階段所引起的輕微的生理變化易被忽視，但早期診斷及治療可以有效的增加患者存活率。表基因體調控是指在不改變基因序列下，而對基因表達有改變。表基因體調控的主要機制有DNA甲基化的改變，組蛋白的修飾，及微小RNA調控。CpG島區DNA甲基化的改變為惡性腫瘤表基因體異常調控之一，本研究利用髮夾彎結構會去結合在特定的基因序列而形成第三股的小分子吡咯咪唑聚酰胺(Pyrrole-imidazole polyamide；) Py-Im辨識G/C(C/G)，而Py-Py辨識T/A(A/T)；並鍵結上功能為透過促進組蛋白乙醯化之N-[4-Chloro-3-(trifluoromethyl)phenyl]-2-ethoxybenzamide（CTB），來改變染色體於組蛋白纏繞的結構而調節基因的表現。本研究以1uM 的 PIP-CTB處理人類口腔鱗狀細胞癌（SCC-25），再利用次世代高通量定序(Next Generation Sequence)的方法分析表基因體調控異常，並藉由Pyrosequence，qRT-PCR 和 Western Blot分別去驗證其中GAD2基因在DNA，mRNA和Protein層面之調控改變，研究PIP-CTB小分子用於特定序列表基因體異常調控之治療，以幫助口腔鱗狀細胞癌病患。

SUMMARY
Head and neck squamous cell carcinoma (HNSCC) is the sixth common human cancer worldwide. Squamous cell carcinomas of the oral region (OSCC) are almost 90% of all HNSCC. The risk factors for oral squamous cell carcinoma are betel quid chewing, smoking, alcohol consuming, UV-exposures and HPV infection. In the early stages, OSCC can go unnoticed and painless with slight physical changes. However, early detection and treatment are important to improve the survival rates. Epigenetics is defined as heritable changes that are not DNA encoded sequence change, but reversible in the cell development and differentiation. The gene function is changed by epigenetics modification. Key mechanisms involved in epigenetic regulation are DNA methylation, histone modifications and micro ribonucleic acids (miRNAs). Previous study revealed the aberrant DNA methylation changes occurred at the promoter CpG island in OSCC. Hairpin pyrrole imidazole(Py-Im) polyamides are nuclease resistant compound that acts as the DNA binding domain (DBD) and synthetic oligomers with programmable sequence. Im/Py bind to the G-C(C-G) base pair and Py/Py bind to the A-T(T-A) on the DNA. The N-(4-Chloro-3-(trifluoromethyl)phenyl)-2-ethoxybenzamide (CTB), a small molecules of histone acetyltransferases (HATs) activator, compounded with pyrrole imidazole polyamide (PIP) of targeting specific DNA binding domain sequences. The synthetic dual-function drug called PIP-CTB that target to the DNA minor groove and effect gene expression. In this study we used high throughput sequence to analyze the genomic target of PIP-CTB by compared the human oral squamous cell carcinoma cell line (SCC-25) treated with 1µM PIP-CTB or without.
Chromatin immunoprecipitation of the methylate binding domain capture DNA and analyzed pH meter by Chip-based semiconductor next-generation sequencing were applied. We measured DNA, mRNA and protein levels of selected GAD2 genes by comparing Pyrosequencing, qRT-PCR and Western Blot from both control and PIP-CTB treated groups. Development of gene regulation PIP-CTB in order to reverse epigenetic deregulation loci susceptible to the epigenetic alter and application as a novel anti-cancer targeting therapy in oral squamous cell carcinoma (OSCC) are the main achievement of this study.

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