Xuan Wenhua, Feng Xiaoke, Qian Chen, Peng Liuying, Shi Yumeng, Xu Lingxiao, Wang Fang, Tan Wenfeng
Department of Rheumatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Department of Traditional Chinese Medicine, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
Cell Biochem Funct. 2017 Apr;35(3):171-177. doi: 10.1002/cbf.3260. Epub 2017 Mar 30.
The migration of osteoclasts (OCs) from circulation and bone marrow into bone surface plays a critical role in the pathogenesis of some bone resorptive diseases, such as rheumatoid arthritis and osteoporosis. To date, how the migration of OCs remains unclear. We investigated gene expression profiling in osteoclastic differentiation of bone marrow-derived macrophages (BMMs) into OCs by microarray analysis. We identified 387 genes overexpressed in osteoclastic differentiation of BMMs. Among them, chemokine CCL4 showed a robust up-regulation signal. High expression of CCL4 was validated in primary BMMs and OC precursor cell line RAW264.7 during differentiation into OCs. The CCL4 neutralization decreased RANKL-induced OC precursor cell migration and invasion in Matrigel-coated transwell membranes assay and in vitro wound healing assay. However, CCL4 inhibition did not affect OCs differentiation and differentiation associated gene expression. The CCL4 inhibition promoted the PI3K phosphorylation at 45 to 60 minutes after RANKL stimulation in RAW264.7. This study indicated that chemokine CCL4 is an important regulator for OCs migration via PI3K pathway, providing a novel therapy target for bone resorptive diseases.
破骨细胞（OCs）从循环系统和骨髓迁移至骨表面在某些骨吸收性疾病（如类风湿性关节炎和骨质疏松症）的发病机制中起关键作用。迄今为止，OCs的迁移方式仍不清楚。我们通过微阵列分析研究了骨髓来源的巨噬细胞（BMMs）向OCs破骨细胞分化过程中的基因表达谱。我们鉴定出387个在BMMs破骨细胞分化过程中过表达的基因。其中，趋化因子CCL4显示出强烈的上调信号。在原代BMMs和OC前体细胞系RAW264.7分化为OCs的过程中，CCL4的高表达得到了验证。在基质胶包被的Transwell膜试验和体外伤口愈合试验中，CCL4中和作用降低了RANKL诱导的OC前体细胞迁移和侵袭。然而，CCL4抑制并不影响OCs的分化及与分化相关的基因表达。在RAW264.7中，CCL4抑制在RANKL刺激后45至60分钟促进了PI3K磷酸化。本研究表明，趋化因子CCL4是通过PI3K途径调节OCs迁移的重要因子，为骨吸收性疾病提供了新的治疗靶点。
