Role of transglutaminase 2 in promoting biglycan synthesis in idiopathic gingival fibromatosis

The mechanism of idiopathic gingival fibromatosis is still unclear. To provide new insights into the molecular and cellular differences between idiopathic gingival fibromatosis and periodontitis, we first identified the gene TGM2, which is differentially expressed between the two. We found that the expression of TGM2 is predominantly lower in idiopathic gingival fibromatosis than in periodontitis, and that the activity of SP1 due to the decreased expression of TGM2 promotes the generation of extracellular matrix-related genes in idiopathic gingival fibromatosis. We have identified biglycan, an extracellular matrix that is specifically upregulated in idiopathic gingival fibromatosis, and highlight the effects of SP1 and TGM2 on biglycan expression. Overall design: Gingival fibroblasts were established from gingiva isolated from patients with idiopathic gingival fibromatosis and periodontitis.Using data obtained from gingival fibroblasts from two patients with idiopathic gingival fibromatosis and one patient with periodontitis, expression variation was analyzed by GO analysis and volcano plots.

特发性牙龈纤维瘤病（idiopathic gingival fibromatosis）的发病机制目前尚未明确。为了揭示特发性牙龈纤维瘤病与牙周炎（periodontitis）在分子及细胞层面的差异，为相关研究提供新视角，我们首先筛选出了二者间存在差异表达的基因TGM2。研究结果显示，相较于牙周炎，特发性牙龈纤维瘤病样本中TGM2的表达水平显著更低；而TGM2表达下调所介导的SP1活性升高，可促进特发性牙龈纤维瘤病中细胞外基质相关基因的表达。我们还鉴定出了在特发性牙龈纤维瘤病中特异性上调的细胞外基质蛋白核心蛋白聚糖（biglycan），并明确了SP1与TGM2对核心蛋白聚糖表达的调控效应。实验整体设计：本研究从特发性牙龈纤维瘤病患者与牙周炎患者的离体牙龈组织中分离培养牙龈成纤维细胞。我们利用2例特发性牙龈纤维瘤病患者及1例牙周炎患者的牙龈成纤维细胞测序数据，通过基因本体（GO, Gene Ontology）富集分析与火山图（volcano plots）对基因表达差异进行分析。