口腔黏膜下纖維化（oral submucous fibrosis；OSF），是一種因為慢性發炎的刺激使上皮萎縮、細胞外基質過度沉積的纖維化疾病，並且已被視為口腔癌前病變的一種；根據研究統計主要發生在東南亞地區的國家，嚼食檳榔的習慣與口腔黏膜下纖維化的發生密不可分；但是目前對於檳榔如何導致OSF的致病機轉尚未研究清楚，因此本實驗是想從已知和許多纖維化疾病相關的上皮-間質轉化（epithelial-mesenchymal transition）機制的轉錄因子Snail著手。先比較在正常人類口腔黏膜纖維母細胞（primary buccal mucosal fibroblasts；BMFs）和口腔黏膜下纖維化纖維母細胞（primary oral submucous fibrosis-drived fibroblasts；OSFs）的EMT轉錄因子Snail本身的表現量，發現OSFs的Snail表現量顯著高於BMFs，表示Snail和OSF之間有所相關性。下一步，在BMFs中加入檳榔中的主要成分檳榔素（arecoline），檢測Snail的表現量是否會和檳榔素的濃度有相關性的表現，結果顯示Snail的表現量都和檳榔素的處理濃度呈現正相關，而當我們將檳榔素處理後BMFs抑制Snail表現之後，此現象也會跟著降低。抑制Snail的表現後發現檳榔素處理後BMFs和OSFs的轉移及侵襲能力會受到抑制，這些結果顯示抑制Snail的表現量會降低檳榔素誘導之BMFs和OSFs的肌纖維母細胞（myofibroblasts）特性。未來希望更進一步研究透徹EMT在OSF致病機轉的分子機制並嘗試找出抑制纖維化的標靶，希望可以發展成為OSF的治療方式。
Oral submucous fibrosis （OSF） is a fibrosis disease because of chronic inflammatory stimulation oral epithelial atrophy and extracellular matrix (ECM) excessive deposition. OSF has been considered as a precancerous condition of oral mucosa, and according to the statistical research seen primarily in Southeast Asia. Betel nut chewing habits is inseparable with OSF pathogenesis, but the mechanisms of areca nut induced OSF are not well understood. The aim of this study was to investigate the epithelial-mesenchymal transition (EMT) transcription factor Snail expression in vitro, as known associated with many fibrotic diseases. We compare the Snail expression in primary buccal mucosal fibroblasts (BMFs) and primary oral submucous fibrosis-drived fibroblasts (OSFs), finding out Snail expression in OSFs is higher than that in BMFs, showing positive correlation between Snail and OSF. We used arecoline (major areca nut alkaloid) to explore whether expression of Snail could be changed dose in BMFs. We observed that the treatment of arecoline dose-dependently increased Snail expression transcript and protein levels in BMFs, while knockdown of Snail reversed these phenomena. Knockdown Snail expression inhibited migration and invasion in arecoline-stimulated BMFs and OSFs. These evidence suggest that knockdown Snail expression might be inhibited arecoline-stimulated myofibroblasts activation and proved Snail involved in the pathogenesis of OSF. This study hence attempts to provide insight EMT mechanism in the pathogenesis of OSF and new strategy for treatment of OSF patients.
