Chen Long, Wang Yuanzheng, Li Senlei, Zhou Wei, Sun Li
Department of Orthopedics, Guizhou Provincial People's Hospital, 550000, Guiyang, Guizhou, China.
Department of Orthopedics, People's Hospital of Yunyan District, 550000, Guiyang, Guizhou, China.
Arthroplasty. 2021 Mar 1;3(1):1. doi: 10.1186/s42836-020-00064-2.
Osteoarthritis (OA), as a common disease, seriously affects the quality of life of the victims, but its pathogenesis remains unclear. It has been confirmed that hypoxia-induced factor (HIF)-mediated hypoxia response plays an important role in the development and progression of OA. As a member of the N-myc downstream regulatory gene families, NDRG3 has been reported to independently regulate the hypoxic response of tumour cells, but the relationship between NDRG3 and OA development has not been reported so far.
In this study, seven OA patients were admitted to Guizhou Provincial People's Hospital from January 2017 to December 2018. The OA group included 5 patients clinically diagnosed with hip/knee OA, which required arthroplasty. The normal group included 2 patients with no previous history of OA and rheumatoid arthritis, which required amputation due to trauma or tumour. The articular cartilage samples were collected to detect the expression of HIF-1α, HIF-2α and NDRG3 using immunohistochemical (IHC), haematoxylin and eosin (HE) and toluidine blue (TB) staining.
HE and TB staining indicated that the cartilage surface of the normal group was smooth and intact, with a columnar arrangement of hyaline chondrocytes, while the cartilage surface of the OA group was discontinuous, with cartilage missing and fibrous soft tissue growing into the defect site. HIF-1α staining was positive in both groups. Moreover, HIF-2α and NDRG3 staining was weakly positive in the normal group, but were uniformly and strongly positive in the OA group. The positively stained areas and integral optical density for NDRG3 were significantly greater in OA group than in the normal group (p < 0.05).
NDRG3 might be closely related to the development and progression of OA. However, the relationship between NDRG3 and OA, which is independent of the HIF pathway, warrants further research.
骨关节炎（OA）作为一种常见疾病，严重影响患者的生活质量，但其发病机制仍不清楚。已证实缺氧诱导因子（HIF）介导的缺氧反应在OA的发生和发展中起重要作用。作为N-myc下游调节基因家族的成员，NDRG3已被报道可独立调节肿瘤细胞的缺氧反应，但迄今为止，NDRG3与OA发展之间的关系尚未见报道。
本研究纳入了2017年1月至2018年12月期间在贵州省人民医院收治的7例OA患者。OA组包括5例临床诊断为髋/膝OA且需要进行关节置换术的患者。正常组包括2例既往无OA和类风湿关节炎病史、因创伤或肿瘤需要截肢的患者。收集关节软骨样本，采用免疫组织化学（IHC）、苏木精-伊红（HE）和甲苯胺蓝（TB）染色检测HIF-1α、HIF-2α和NDRG3的表达。
HE和TB染色显示，正常组软骨表面光滑完整，透明软骨细胞呈柱状排列，而OA组软骨表面不连续，有软骨缺失，纤维软组织长入缺损部位。两组HIF-1α染色均为阳性。此外，正常组HIF-2α和NDRG3染色弱阳性，而OA组均为强阳性。OA组NDRG3阳性染色面积和积分光密度显著大于正常组（p < 0.05）。
NDRG3可能与OA的发生和发展密切相关。然而，NDRG3与OA之间独立于HIF途径的关系值得进一步研究。
