Pap T, Aupperle K R, Gay S, Firestein G S, Gay R E
University Hospital, Zurich, Switzerland.
Arthritis Rheum. 2001 Mar;44(3):676-81. doi: 10.1002/1529-0131(200103)44:3<676::AID-ANR117>3.0.CO;2-6.
In vitro data suggest that the tumor suppressor p53 is critically involved in the regulation of proliferation and apoptosis in fibroblast-like synoviocytes (FLS). Based on evidence that abnormalities in p53 expression and function are found in rheumatoid arthritis (RA), we analyzed whether inhibition of p53 using gene transfer with the human papilloma virus type 18 (HPV-18) E6 protein results in an increased cellularity and invasiveness of synovial fibroblasts in vivo.
RA and normal FLS were transduced with a pLXSN-based construct encoding for the HPV-18 E6 protein or with the pLXSN vector alone. After selection with G418, FLS were coimplanted with normal human cartilage under the renal capsule of SCID mice. Parental, nontransduced cells were used as additional controls. After 60 days, the implants were removed, and FLS invasion into the cartilage, perichondrocytic degradation, and cellularity were assessed.
Nontransduced and mock-transduced RA FLS exhibited characteristic invasion into the cartilage (mean +/- SEM scores 2.2 +/- 0.3 and 2.4 +/- 0.2, respectively). Invasion was increased significantly in the E6-transduced RA FLS (mean score 3.1 +/- 0.3; P < 0.05). Inhibition of p53 also resulted in an increase in cellularity. Parental and mock-transduced normal FLS did not exhibit significant invasion (mean score 1.5 +/- 0.1 and 1.4 +/- 0.3, respectively), but transduction with E6 resulted in clear invasiveness (mean score 2.4 +/- 0.4) as well as increased cellularity.
The data suggest that inhibition of endogenous p53 leads to increased invasiveness and cellularity of RA FLS and may also transform normal FLS to cells that display an aggressive, RA FLS-like behavior. Therefore, abnormalities such as somatic mutations in the p53 tumor suppressor may contribute to synovial hyperplasia and invasion in RA.
体外实验数据表明，肿瘤抑制因子p53在成纤维样滑膜细胞（FLS）的增殖和凋亡调控中起关键作用。基于类风湿关节炎（RA）中存在p53表达和功能异常的证据，我们分析了利用人乳头瘤病毒18型（HPV - 18）E6蛋白进行基因转移抑制p53是否会导致体内滑膜成纤维细胞的细胞数量增加和侵袭性增强。
用基于pLXSN的构建体转导RA和正常FLS，该构建体编码HPV - 18 E6蛋白，或仅用pLXSN载体转导。经G418筛选后，将FLS与人正常软骨共同植入SCID小鼠的肾被膜下。未转导的亲代细胞用作额外对照。60天后，取出植入物，评估FLS对软骨的侵袭、软骨周细胞降解及细胞数量。
未转导和模拟转导的RA FLS表现出对软骨的特征性侵袭（平均±标准误评分分别为2.2±0.3和2.4±0.2）。E6转导的RA FLS侵袭显著增加（平均评分3.1±0.3；P<0.05）。p53的抑制也导致细胞数量增加。亲代和模拟转导的正常FLS未表现出明显侵袭（平均评分分别为1.5±0.1和1.4±0.3），但E6转导导致明显的侵袭性（平均评分2.4±0.4）以及细胞数量增加。
数据表明，内源性p53的抑制导致RA FLS的侵袭性和细胞数量增加，也可能将正常FLS转化为表现出侵袭性、类似RA FLS行为的细胞。因此，p53肿瘤抑制因子的体细胞突变等异常可能促成RA中的滑膜增生和侵袭。
