β-链接素与基质金属蛋白酶-7在大肠腺瘤及其癌变组织表达的意义

Significance of β-catenin and matrix metalloproteinase-7 expressions in colorectal adenoma and malignant tissue

目的探讨β链接素(β-catenin,β-cat)和基质金属蛋白酶-7(matrixmetalloproteinase7,MMP-7)表达与大肠腺瘤癌变的关系。方法应用组织芯片和免疫组化技术检测β-cat和MMP-7在25例大肠正常黏膜及135例腺瘤及腺瘤癌变组织的表达。结果(1)腺瘤癌变组织β-cat胞质、胞核表达率分别为68.4%、40.4%,显著高于腺瘤(40.0%、16.0%)及正常粘膜(4.0%、0.0%,均为P<0.01)。(2)高级别与低级别上皮内肿瘤相比β-cat胞质、胞核表达率显著升高(均为P<0.05),而胞膜表达率无显著性差异(P>0.05)。(3)正常黏膜、腺瘤、腺瘤癌变组织MMP-7阳性表达率依次增高,腺瘤癌变组织MMP-7阳性表达率(45.6%)显著高于正常黏膜(16.0%,P<0.05)。(4)大肠腺瘤及其癌变组织中β-cat胞质、胞核表达与MMP-7阳性表达均呈正相关关系(均为P<0.001)。结论β-cat胞质/胞核表达及MMP-7阳性表达与大肠腺瘤癌变的发生有关;β-cat与MMP-7的协同表达可能在腺瘤恶性转化过程中发挥着重要的作用。

Objective To explore the correlation of β-catenin a nd matrix metalloproteinase-7 (MMP-7) expression with maligancy of human color ectal adenoma. Methods The expressions of β-catenin and MMP-7 were dete cted by immunohistochemical staining in tissue microarrays including 25 cases of normal mucosa and 135 cases of colorectal adenoma and adenoma with malignant ch anges. Results The cytoplasmic and nuclear β-catenin expression rate was 68.4% and 40.4% in malignant tissue in adenoma, respectively, which wa s significantly higher than that of adenoma (40.0% and 16.0%) and normal muc osa (4.0% and 0.0%, P<0.01). Compared with low-grade intra-epithelial neop lasia, both cytoplasmic and nuclear β-catenin expression rates in high-grade intra-epithelial neoplasia markedly increased (both P<0.05), while the memb ranous expression rates were not different. The positive expression rate of MMP -7 gradually increased from normal mucosa, adenoma to adenoma with malignant ch anges. The positive expression rate of MMP-7 in adenoma with malignant changes was significantly higher than that of normal mucosa (45.6% vs 16.0%, P<0 .05). Both cytoplasmic and nuclear β-catenin expression were positively correl ated with positive expression of MMP-7 in adenoma and in adenoma with malignant changes (P<0.001). Conclusions The cytoplasmic and nuclear β-catenin expres sion and were positively correlated with the positive expression of MMP-7 in co lorectal adenoma with malignant changes. Synergistic expression of β-catenin a nd MMP-7 may play an important role in malignant transformation of colorectal a denoma.