血管生成拟态在翼状胬肉进展中的作用及可能机制

目的　研究血管生成拟态（VM）在翼状胬肉进展中的作用及其与基质金属蛋白酶-2（MMP-2）、基质金属蛋白酶-9（MMP-9）和血管内皮生长因子（VEGF）表达的关系，探讨VM与翼状胬肉进展的相关性及可能机制。方法　筛选符合条件的翼状胬肉标本，进行胬肉分期（静止期/进展期）、分型（初发型/复发型）及临床特征指标采集。采用CD31/PAS双重染色检测不同类型翼状胬肉中VM的形成差异。以初发型进展期翼状胬肉为研究对象，HE染色观察病理特征，免疫组织化学染色及Western blot检测MMP-2、MMP-9及VEGF的表达，分析VM与初发型进展期翼状胬肉临床病理特征及MMP-2、MMP-9、VEGF的相关性。结果　静止期翼状胬肉VM阳性率为15.38%，进展期翼状胬肉VM阳性率为68.50%，组间差异具有统计学意义（P=0.000）；初发型翼状胬肉VM阳性率为40.80%，复发型翼状胬肉VM阳性率为81.48%，组间差异亦具有统计学意义（P=0.000）。VM与进展期及复发型翼状胬肉均呈正相关（均为P<0.05)。VM阳性的初发型进展期翼状胬肉组织，其血管分级、上皮细胞层数、杯状细胞数、成纤维细胞数、血管数、炎症细胞数、纤维化程度、MMP-2、MMP-9及VEGF的表达均明显高于VM阴性者，而变性程度低于VM阴性者，差异均有统计学意义（均为P<0.05）。初发型进展期翼状胬肉VM与翼状胬肉血管分级、上皮细胞层数、杯状细胞数、成纤维细胞数、血管数、炎症细胞数、纤维化程度、MMP-2、MMP-9及VEGF的表达均呈正相关，与胬肉变性程度呈负相关（均为P<0.05)。结论　翼状胬肉组织中存在VM结构，可作为其血供途径之一，VM可促进翼状胬肉的进展，MMP-2、MMP-9及VEGF可能是翼状胬肉VM形成的分子机制。

Role of vasculogenic mimicry in the development of pterygium and its possible mechanism

Objective　To investigate the role of vasculogenic mimicry (VM) in the development of pterygium and its correlation with the expression of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9) and vascular endothelial growth factor (VEGF), and explore the correlation between VM and pterygium progression and its possible mechanism.Methods　Qualified pterygium specimens were screened, and their staging (quiescent/progressive stage), typing (initial onset/relapsing type) and clinical characteristics were collected. CD31/PAS double staining was performed to detect the difference in VM formation in different types of pterygiums. Initial-onset progressive pterygiums were selected for further research. Their clinicopathological features were observed by Hematoxylin and Eosin staining,and the expression levels of MMP-2, MMP-9 and VEGF were measured by immunohistochemical staining and Western blot. The relevance of VM to the clinicopathological features and the expression levels of MMP-2, MMP-9 and VEGF was analyzed.Results　The positive rate of VM was 15.38%in quiescent pterygiums and 68.50% in progressive pterygiums (P=0.000), 40.80% in initial-onset pterygiums and 81.48% in relapsing pterygiums (P=0.000). VM was positively correlated with progressive and relapsing pterygiums (both P<0.05). The vascular grading, the numbers of epithelial cell layers, goblet cells, fibroblasts, blood vessels and inflammatory cells, the degree of fibrosis, and the expression of MMP-2, MMP-9 and VEGF in initial-onset progressive pterygiums with VM positive were significantly higher than those with VM negative, while the degree of degeneration was observably lower (all P<0.05). VM in the initial-onset progressive pterygiums was positively correlated with the vascular grading, the numbers of epithelial cell layers, goblet cells, fibroblasts, blood vessels and inflammatory cells, the degree of fibrosis, and the expression of MMP-2, MMP-9 and VEGF, and negatively correlated with the degree of degeneration (all P<0.05). Conclusion　VM exists in pterygiums and can be used as one of the blood supply routes.It can also promote the development of pterygium. MMP-2, MMP-9 and VEGF may act as the molecular mechanism for VM formation in pterygium.