Department of Urology, Eberhard Karls University of Tübingen, Tübingen, Germany.
World J Urol. 2010 Jun;28(3):335-41. doi: 10.1007/s00345-009-0492-z. Epub 2009 Dec 13.
Renal cell carcinomas (RCC) frequently express the gastrin-releasing peptide receptor (GRP-R). Gastrin-releasing peptide (GRP) stimulates tumor cell proliferation and neoangiogenesis. Tumor-associated macrophages (TAM) comprise an important cellular component of these tumors. We analyzed the GRP/GRP-R network in clear cell RCC (ccRCC) and non-clear cell RCC (non-ccRCC) with special regard to its expression by macrophages, tumor cells and microvessels.
Gastrin-releasing peptide and GRP-R expression in 17 ccRCC and 9 non-ccRCC were analyzed by RT-PCR, immunohistochemistry and double immunofluorescence staining.
Tumor-associated macrophages expressed GRP and GRP receptor in ccRCC. Tumor cells and microvessels showed low to intermediate GRP-R expression in nearly all cases. In 12 ccRCC tumor epithelia also expressed low levels of GRP. Microvascular GRP expression was found in nine cases of ccRCC. For non-RCC, the expression of GRP and GRP receptor expression pattern was similar.
Tumor-associated macrophages are the main source of GRP in RCC. GRP receptor on TAM, tumor epithelia and microvessels might be a molecular base of a GRP/GRP receptor network, potentially acting as a paracrine/autocrine modulator of TAM recruitment, tumor growth and neoangiogenesis.
肾细胞癌 (RCC) 常表达胃泌素释放肽受体 (GRP-R)。胃泌素释放肽 (GRP) 可刺激肿瘤细胞增殖和新生血管形成。肿瘤相关巨噬细胞 (TAM) 是这些肿瘤的重要细胞成分。我们分析了透明细胞 RCC (ccRCC) 和非透明细胞 RCC (non-ccRCC) 中的 GRP/GRP-R 网络，特别关注巨噬细胞、肿瘤细胞和微血管对其的表达。
采用 RT-PCR、免疫组织化学和双免疫荧光染色分析 17 例 ccRCC 和 9 例 non-ccRCC 中胃泌素释放肽和 GRP-R 的表达。
ccRCC 中的肿瘤相关巨噬细胞表达 GRP 和 GRP 受体。肿瘤细胞和微血管在几乎所有病例中均表现出低至中等水平的 GRP-R 表达。在 12 例 ccRCC 肿瘤上皮中也发现了低水平的 GRP。在 9 例 ccRCC 中发现了微血管 GRP 的表达。对于非 RCC，GRP 和 GRP 受体表达模式相似。
肿瘤相关巨噬细胞是 RCC 中 GRP 的主要来源。TAM、肿瘤上皮和微血管上的 GRP-R 可能是 GRP/GRP 受体网络的分子基础，可能作为 TAM 募集、肿瘤生长和新生血管形成的旁分泌/自分泌调节剂。
