Vallbo Christina, Damber Jan-Erik
Institute of Surgical Sciences, Department of Urology, Göteborg University, Sweden.
Acta Oncol. 2005;44(3):293-8. doi: 10.1080/02841860410002806.
Thrombospondin is a potent inhibitor of angiogenesis and might therefore be important in controlling tumour growth. TSP interacts with a number of proteases and receptors and in this way inhibits stimulation of angiogenesis. An earlier study showed that thrombospondin is expressed in benign prostatic hyperplasia (BPH) and high-grade prostatic intraepithelial neoplasia (PIN) but is absent in prostate cancer. The present study was therefore designed to evaluate the expression of thrombospondin 1 and 2 (TSP-1, TSP-2), TSP receptors CD36 and CD47, and matrix-metalloproteases 2 and 9 (MMP-, MMP-9) in a rat prostate cancer model. By using immunohistochemistry, Western blot, and real-time PCR the expression patterns of TSP-1, TSP-2, CD36, CD47, MMP-2, and MMP-9 were investigated in normal rat prostate tissue and five malignant Dunning sublines tissue. TSP-1 mRNA levels were decreased in all tumours compared with normal prostate. However, there was no difference in expression of TSP-2 and CD36 mRNA in these samples. MMP-2 was increased with malignancy, but no expression of MMP-9 was seen. The CD47 receptor did slightly increase with malignancy except for H3327. The results showed that thrombospondin is expressed in normal prostate but not in prostate tumours in a rat model. Simultaneously, MMP-2 expression increases with malignancy.
血小板反应蛋白是一种有效的血管生成抑制剂，因此可能在控制肿瘤生长中起重要作用。血小板反应蛋白与多种蛋白酶和受体相互作用，从而抑制血管生成的刺激。早期研究表明，血小板反应蛋白在良性前列腺增生（BPH）和高级别前列腺上皮内瘤变（PIN）中表达，但在前列腺癌中不存在。因此，本研究旨在评估血小板反应蛋白1和2（TSP-1、TSP-2）、TSP受体CD36和CD47以及基质金属蛋白酶2和9（MMP-2、MMP-9）在大鼠前列腺癌模型中的表达。通过免疫组织化学、蛋白质印迹和实时PCR，研究了TSP-1、TSP-2、CD36、CD47、MMP-2和MMP-9在正常大鼠前列腺组织和五种恶性邓宁亚系组织中的表达模式。与正常前列腺相比，所有肿瘤中的TSP-1 mRNA水平均降低。然而，这些样本中TSP-2和CD36 mRNA的表达没有差异。MMP-2随着恶性程度增加，但未观察到MMP-9的表达。除H3327外，CD47受体确实随着恶性程度略有增加。结果表明，在大鼠模型中，血小板反应蛋白在正常前列腺中表达，但在前列腺肿瘤中不表达。同时，MMP-2表达随着恶性程度增加。
