Ludwig H C, Feiz-Erfan I, Bockermann V, Behnke-Mursch J, Schallock K, Markakis E
Georg-August-Universität, Göttingen, Germany.
Anticancer Res. 2000 Jan-Feb;20(1A):299-304.
Nitric oxide (NO) is synthesized from arginine by three different isozymes of nitric oxide synthase (NOS I-III). NO has been identified as a powerful metabolite of vascular smooth muscle cell function, cerebral blood circulation and oedema induction. NOS induction by different cytokines has been shown previously in glioblastoma cell cultures and NOS III expression due to astrocytoma grading has been shown in several tumors recently. The aim of the present study was to study the coexpression of NOS I-III, macrophage and capillary presence with VEGF, EGF and their receptors and to investigate a possible mechanism in peritumoral oedema generation.
We have investigated the expression (4-grade values, blinded assay by two observers) of NOS I-III together with those of VEGF, VEGF- R (Flt-1), EGF-R1, von-Willebrand-factor (VWF) and a pan-macrophage marker (Ki-M1P) immunohistochemically in tumor specimens from 220 patients and performed tumor volume morphometry by image analysis in a subgroup of 32 cases to test for any correlation with the peritumoral oedema volumes. Inducible NOS II was further investigated by in situ labelling with a DNA oligonucleotide probe cocktail.
All of the specimens revealed some NOS expression, NOS II was expressed in macrophages, microglia and endothelial cells, NOS III and I was localized in glioblastoma cells, NOS III in endothelial cells as well. The highest degrees of expression were observed in 46% (NOS I), 22% (NOS II) and 75% (NOS III) of all specimens. Inducible NOS II in any expression grade was observed in 47.5% of the specimens. Significant correlations were observed for the expression of the macrophage marker Ki-M1P with NOS II (p = 0.024), endothelial NOS III with NOS I (p = 0.0003), VEGF-R1 with NOS II (p = 0.0008) and NOS III (p = 0.011) The oedema volumes could not be correlated significantly with NOS or VEGF-R1 expression values but with those of endothelial staining (p = 0.02). We observed a trend towards higher Ki-M1P expression values together with higher oedema volume extensions. In situ hybridization demonstrated reaction products in endothelial and perivascular regions and sometimes scattered throughout the specimens revealing the labelling of macrophages.
The main source of NO is NOS I and NOS III. The latter is located in endothelial cells and glioblastoma cells. The expression of NOS II in glioblastomas is restricted to infiltrating macrophages. NOS II and III expressions were observed significantly together with that of VEGF-R1. Neither NOS I-III nor VEGF-R expression could be correlated with the extension of the peritumoral oedema.
一氧化氮（NO）由一氧化氮合酶（NOS I - III）的三种不同同工酶从精氨酸合成。NO已被确认为血管平滑肌细胞功能、脑血液循环和水肿诱导的强效代谢产物。先前在胶质母细胞瘤细胞培养中已显示不同细胞因子可诱导NOS，最近在几种肿瘤中也已显示由于星形细胞瘤分级导致的NOS III表达。本研究的目的是研究NOS I - III、巨噬细胞和毛细血管与血管内皮生长因子（VEGF）、表皮生长因子（EGF）及其受体的共表达情况，并探讨瘤周水肿产生的可能机制。
我们采用免疫组织化学方法研究了220例患者肿瘤标本中NOS I - III与VEGF、VEGF受体（Flt - 1）、EGF受体1、血管性血友病因子（VWF）和一种泛巨噬细胞标志物（Ki - M1P）的表达（4级评分，由两名观察者进行盲法检测），并对32例亚组病例进行图像分析以测量肿瘤体积，以检测与瘤周水肿体积的任何相关性。通过用DNA寡核苷酸探针混合物进行原位标记进一步研究诱导型NOS II。
所有标本均显示出一定程度的NOS表达，NOS II在巨噬细胞、小胶质细胞和内皮细胞中表达，NOS III和I定位于胶质母细胞瘤细胞，NOS III也在内皮细胞中表达。在所有标本中，46%（NOS I）、22%（NOS II）和75%（NOS III）观察到最高表达程度。47.5%的标本观察到任何表达级别的诱导型NOS II。观察到巨噬细胞标志物Ki - M1P的表达与NOS II显著相关（p = 0.024），内皮NOS III与NOS I显著相关（p = 0.0003），VEGF受体1与NOS II显著相关（p = 0.0008）和与NOS III显著相关（p = 0.011）。水肿体积与NOS或VEGF受体1的表达值无显著相关性，但与内皮染色相关（p = 0.02）。我们观察到Ki - M1P表达值越高，水肿体积扩展越大的趋势。原位杂交在内皮和血管周围区域显示反应产物，并有时散布于整个标本中，揭示了巨噬细胞的标记。
NO的主要来源是NOS I和NOS III。后者位于内皮细胞和胶质母细胞瘤细胞中。胶质母细胞瘤中NOS II的表达仅限于浸润的巨噬细胞。观察到NOS II和III的表达与VEGF受体1的表达显著相关。NOS I - III和VEGF受体的表达均与瘤周水肿的扩展无相关性。
