Pigmented villonodular synovitis (PVNS) is a rare hyperplasia disease of the synovium with a predilection for the knee in either a localized (LPVNS) or a diffuse form (DPVNS). But the exact cause is not clear. The aim of this study was to explore the relationship between the expression of cellular inhibitor of apoptosis 2 (cIAP2) and proliferation, apoptosis, invasive growth and postoperative recurrence in PVNS. Clinical significance of cIAP2 expression in synovium from 63 patients’ knee joints with PVNS (40 DPVNS; 23 LPVNS) were investigated with 20 normal subjects acting as controls. The cIAP2 gene was screened by Human Cancer Pathway Finder PCR Array and real-time polymerase chain reaction (RT-PCR). We also used immunohistochemistry to detect cIAP2 and proliferating cell nuclear antigen (PCNA) protein expression and analyzed their relationship with PVNS type, invasive growth, and postoperative recurrence. The expression of cIAP2, PCNA, caspase-8, caspase-9 and caspase-3 protein was tested in Western blot. Screening results of Human Cancer Pathway Finder PCR array and RT-PCR showed significantly more cIAP2 mRNA in DPVNS synovium than in normal or LPVNS synovium (P < 0.05). Immunohistochemistry and western blot showed that the cIAP2 protein expression level in DPVNS was significantly higher than in LPVNS tissue (P < 0.01). As cIAP2 expression increased, the expression of PCNA increased (P < 0.05) and expression of cleaved caspase-3, -8, -9 decreased (P < 0.01). cIAP2 and PCNA overexpression were found to be related to ligament and bone erosion in PVNS and to disease recurrence (P < 0.05). This study suggested that cIAP2 overexpression plays an important role in the anti-apoptotic, proliferative and invasive growth of PVNS, which may account for the recurrence and poor prognosis of DPVNS.

色素沉着绒毛结节性滑膜炎 (PVNS) 是一种罕见的滑膜增生性疾病，以局部 (LPVNS) 或弥漫性 (DPVNS) 形式发生于膝关节。但具体原因尚不清楚。本研究旨在探讨细胞凋亡抑制因子2（cIAP2）的表达与PVNS增殖、凋亡、侵袭性生长和术后复发的关系。以 20 名正常受试者作为对照，研究了 63 名 PVNS 患者（40 名 DPVNS；23 名 LPVNS）膝关节滑膜中 cIAP2 表达的临床意义。cIAP2基因通过Human Cancer Pathway Finder PCR Array和实时聚合酶链反应（RT-PCR）进行筛选。我们还使用免疫组织化学检测 cIAP2 和增殖细胞核抗原 (PCNA) 蛋白表达，并分析它们与 PVNS 类型、侵袭性生长和术后复发的关系。在蛋白质印迹中测试了 cIAP2、PCNA、caspase-8、caspase-9 和 caspase-3 蛋白的表达。Human Cancer Pathway Finder PCR array 和 RT-PCR 的筛选结果显示 DPVNS 滑膜中 cIAP2 mRNA 明显多于正常或 LPVNS 滑膜。P  < 0.05)。免疫组织化学和蛋白质印迹显示，DPVNS 组织中 cIAP2 蛋白表达水平显着高于 LPVNS 组织（P  < 0.01）。随着cIAP2表达的增加，PCNA的表达增加（P  < 0.05），cleaved caspase-3、-8、-9的表达降低（P  < 0.01）。发现 cIAP2 和 PCNA 过表达与 PVNS 中的韧带和骨侵蚀以及疾病复发有关（P  < 0.05）。本研究表明cIAP2过表达在PVNS的抗凋亡、增殖和侵袭性生长中起重要作用，这可能是DPVNS复发和预后不良的原因。