Vukovic Vojislav, Nicklee Trudey, Hedley David W
Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada.
Int J Radiat Oncol Biol Phys. 2002 Mar 1;52(3):837-43. doi: 10.1016/s0360-3016(01)02716-x.
Aberrant architecture of the tumor vasculature and temporal fluctuations in blood flow can result in tumor hypoxia. The aim of this study was to classify tumor hypoxia based on distance to blood vessels, and to characterize its biologic significance by determining levels of nonprotein sulfhydryls (NPSH) in hypoxic regions located proximally and distally to tumor blood vessels.
A dual fluorescence method was developed for the spatial colocalization of the vasculature and hypoxia in frozen sections from SiHa cervical carcinoma xenografts. A parallel section was stained with the sulfhydryl stain mercury orange. Composite fluorescence images were generated by imaging and tiling individual fields of view into 2D image arrays. Image arithmetic techniques were combined with feature-based image segmentation to characterize expression of NPSH as a function of the hypoxic tumor microenvironment.
NPSH levels were higher in hypoxic areas of the SiHa xenografts (15.1 +/- 0.5 vs. 13.5 +/- 0.5 integrated optical density [IOD], p < 0.03). When tumor hypoxia was classified by distance to the nearest visible blood vessel, significantly higher NPSH levels were found in hypoxic regions close to blood vessels than in regions at a distance from blood vessels.
The results of this study indicate differential expression of NPSH levels in regions of hypoxia that are proximal or distal to blood vessels in SiHa tumors.
肿瘤血管结构异常和血流的时间波动可导致肿瘤缺氧。本研究的目的是根据与血管的距离对肿瘤缺氧进行分类，并通过测定肿瘤血管近端和远端缺氧区域的非蛋白巯基（NPSH）水平来表征其生物学意义。
开发了一种双荧光方法，用于对SiHa宫颈癌异种移植瘤冰冻切片中的血管和缺氧进行空间共定位。用巯基染色剂汞橙对平行切片进行染色。通过对各个视野进行成像并将其拼接成二维图像阵列来生成复合荧光图像。将图像算术技术与基于特征的图像分割相结合，以表征NPSH的表达作为缺氧肿瘤微环境的函数。
SiHa异种移植瘤缺氧区域的NPSH水平较高（积分光密度[IOD]为15.1±0.5 vs. 13.5±0.5，p<0.03）。当根据与最近可见血管的距离对肿瘤缺氧进行分类时，发现靠近血管的缺氧区域的NPSH水平明显高于远离血管的区域。
本研究结果表明，SiHa肿瘤中血管近端或远端缺氧区域的NPSH水平存在差异表达。
