Abstract

Objective: To explore the role of WNT family member 1 (WNT1) in the development of dysplasia of the hip (DDH) and the molecular mechanism involved in this process. Methods: Si-WNT1, pcDNA3.1-WNT1 or corresponding negative controls were transfected into human osteoblast hFOB1.19 and human chondrocyte C28/I2, respectively. The proliferation of cells was measured by EdU assay. The relative expressions of human noggin gene (NOG), growth differentiating factor 5 (GDF5), WNT1, and WNT1-inducible-signaling pathway protein 2 (WISP2) were determined by immunofluorescence analysis. The protein expressions of RNA-binding protein of multiple splice forms 2 (RBPMS2), NOG, bone morphogenetic protein 2 (BMP2), BMP4, WNT1 and WISP2 were determined by western blot. Animal experiment was also performed and the morphological development of hip joint was observed. Results: Overexpression of WNT1 promoted osteoblast proliferation and inhibited chondrocyte proliferation, while knockdown of WNT1 inhibited osteoblast proliferation. In chondrocytes, knockdown of WNT1 upregulated NOG expression, while overexpression of WNT1 downregulated its expression. In osteoblasts and chondrocytes, overexpression of WNT1 increased BMP2, BMP4, WNT1, and WISP2 expression. RBPMS2 and NOG were slightly expressed in each group. Conclusion: Overexpression of WNT1 promoted osteoblast proliferation, inhibited chondrocyte proliferation, and increased the expressions of BMP2, BMP4, WNT1, and WISP2. Therefore, WNT1 may be a new therapeutic target for DDH.

摘要

目的：探讨WNT家族成员1（WNT1）在髋关节发育不良（DDH）发生过程中的作用及其分子机制。方法：将Si-WNT1、pcDNA3.1-WNT1或相应的阴性对照分别转染到人成骨细胞hFOB1.19和人软骨细胞C28/I2中。通过 EdU 测定法测量细胞的增殖。通过免疫荧光分析确定人头蛋白基因 (NOG)、生长分化因子 5 (GDF5)、WNT1 和 WNT1 诱导信号通路蛋白 2 (WISP2) 的相对表达。通过蛋白质印迹法测定多剪接形式的RNA结合蛋白2（RBPMS2）、NOG、骨形态发生蛋白2（BMP2）、BMP4、WNT1和WISP2的蛋白表达。还进行了动物实验，观察了髋关节的形态发育。结果: WNT1 的过表达促进成骨细胞增殖并抑制软骨细胞增殖，而 WNT1 的敲低抑制成骨细胞增殖。在软骨细胞中，WNT1 的敲低上调了 NOG 的表达，而 WNT1 的过表达则下调了其表达。在成骨细胞和软骨细胞中，WNT1 的过表达增加了 BMP2、BMP4、WNT1 和 WISP2 的表达。RBPMS2 和 NOG 在各组中均有轻微表达。结论：WNT1过表达促进成骨细胞增殖，抑制软骨细胞增殖，增加BMP2、BMP4、WNT1、WISP2的表达。因此，WNT1 可能是 DDH 的新治疗靶点。