口腔黏膜下纖維化症中α-SMA表現之研究

Abstract

口腔黏膜下纖維化症( Oral submucous fibrosis，OSF)是一種慢性發炎的口腔黏膜病變， 因嚼食檳榔而使口腔黏膜下的結締組織層產生過多的膠原蛋白，並過度堆積所造成的潛在性癌變障礙。 在許多研究中發現，在肺臟、肝臟、皮膚的纖維化症疾病中，其纖維母細胞都有過度的α-Smooth muscle actin (α-SMA)表現。因此，本研究的目的在探討 α-SMA與口腔黏膜下纖維化症致病機轉的關聯性。首先我們利用α-SMA抗體進行免疫組織化學染色法，偵測α-SMA在正常口腔頰黏膜組織(normal oral mucosa；NOM )與口腔黏膜下纖維化症組織(OSF)的表現情形。結果發現 NOM組織只在血管的平滑肌細胞( positive control )有表現α-SMA ，而OSF 組織其纖維母細胞卻有α-SMA 過度表現。其次，我們將NOM纖維母細胞以TGF-β或Arecoline處理之後， 萃取其蛋白質以西方墨點法分析之，發現這兩者都能誘導 α-SMA 的表現量增加， 並且呈現 dose-dependent 的情形。 最後， 我們利用 Curcumin和Epigallocatechin-3-gallate ( EGCG )， 以及 Histone deacetylase (HDAC) 的抑制劑 Trichostatin A (TSA) 這幾種藥物作用於NOM纖維母細胞， 發現它們都能抑制Arecoline或TGF-β誘導α-SMA的表現量增加。 在本研究中，我們證實了口腔黏膜下纖維化症的纖維母細胞會比正常口腔頰黏膜纖維母細胞表現較多的α-SMA。而Arecoline 和TGF-β 確實可以誘導口腔頰黏膜纖維母細胞表現較多的α-SMA蛋白質，最後我們發現EGCG、Curcumin 及TSA都可以有效的降低正常口腔頰黏膜纖維母細胞α-SMA蛋白質的表現量。 關鍵字：口腔黏膜下纖維化症、OSF、α-SMA

Oral submucous fibrosis (OSF) is a chronic and inflammatory disease of oral mucous. Epidemiological evidences strongly indicate the association of chewing areca quid habit and OSF which is a kind of potentially malignant disorders. Many evidences have showed that α-smooth muscle actin (α-SMA) is overexpressed in some organs, such as lung, liver, and skin, but the α-SMA expression in OSF is not clear, therefore, in this study, we investigated the correlation of α-SMA expression and the pathogenesis in OSF by immunohistochemistry (IHC). The result shows that the expression of α-SMA in normal buccal mucosa only exists in the smooth muscle cells (positive control) of blood vessels, however, α-SMA is overexpressed in OSF. For detecting the effect of arecoline and TGF-β in OSF we treated normal oral mucous fibroblasts (NOM) with above components, and then analyzed the expression of α-SMA by Western Blot. The result showed that both arecoline and TGF-β were able to induce the expression of α-SMA in the dose-dependent manner. Finally, we treated NOM with Curcumin, Epigallocatechin-3-gallate (EGCG), or Trichostatin A (TSA), the result showed that all of them were able to reduce the expression of α-SMA induced by arecoline or TGF-β. In our study, we found that OSF expressed much more α-SMA than NOM. Besides, both arecoline and TGF-β can induce the expression of α-SMA. The induced expression of α-SMA by arecoline or TGF-β can be reduced by Curcumin, EGCG, or TSA. Keywords: oral submucous fibrosis, OSF, α-SMA