Save Sight Institute, Sydney Medical School, New South Wales, Australia.
Clin Exp Ophthalmol. 2010 Jan;38(1):43-8. doi: 10.1111/j.1442-9071.2009.02216.x.
To investigate the expression of Wnt signalling pathway genes in keratoconic (KC) epithelium.
RNA was extracted from the epithelium of four KC patients undergoing corneal transplantation and five age-matched controls. The expression of 84 genes known to be involved in the Wnt signalling pathway was tested by reverse transcription-polymerase chain reaction (RT-PCR) with a pathway-targeted array (Human Wnt RT(2) Profiler PCR Array, Superarray).
Using RT-PCR arrays, LEF1, PITX2 and secreted frizzled-related protein 1 (SFRP1) were upregulated more than twofold in KC compared with control epithelium. Only SFRP1 was significantly upregulated, approximately 25-fold compared with pooled controls (range 9.12-fold to 98.6-fold; P = 0.019). SFRP1 expression was associated with patient age and possibly the rate of progression of the keratoconus. Immunohistochemistry was used to assess SFRP1 protein distribution and confirm the SFRP1 microarray result (n = 3 KC and n = 2 control corneas). SFRP1 immunolablelling was seen in all KC corneas, mostly in the basal epithelium; however, control corneas showed minimal SFRP1 immunoreactivity.
SFRP1 is highly upregulated in the epithelium of these KC patients, suggesting a role in the pathogenesis and progression of keratoconus. Future investigations are required to establish if SFRP1 may be a potential marker of KC progression or if manipulation of its expression can be used to therapeutic effect in this disease.
研究 Wnt 信号通路基因在圆锥角膜（KC）上皮中的表达。
从 4 名接受角膜移植的 KC 患者和 5 名年龄匹配的对照者的角膜上皮中提取 RNA。通过逆转录-聚合酶链反应（RT-PCR）用靶向通路的阵列（Human Wnt RT(2) Profiler PCR Array，Superarray）检测已知参与 Wnt 信号通路的 84 个基因的表达。
使用 RT-PCR 阵列，与对照组上皮相比，KC 中 LEF1、PITX2 和分泌型卷曲相关蛋白 1（SFRP1）的表达上调了两倍以上。只有 SFRP1 显著上调，与混合对照组相比约 25 倍（范围 9.12 倍至 98.6 倍；P = 0.019）。SFRP1 表达与患者年龄和可能的圆锥角膜进展速度有关。免疫组织化学用于评估 SFRP1 蛋白分布并确认 SFRP1 微阵列结果（n = 3 KC 和 n = 2 对照角膜）。在所有 KC 角膜中均可见 SFRP1 免疫标记，主要在上皮基底；然而，对照角膜显示出最小的 SFRP1 免疫反应性。
这些 KC 患者的上皮中 SFRP1 高度上调，表明其在圆锥角膜的发病机制和进展中起作用。需要进一步研究以确定 SFRP1 是否可能是 KC 进展的潜在标志物，或者其表达的操纵是否可以在该疾病中用于治疗效果。
