Nathan Saminathan S, Huvos Andrew G, Casas-Ganem Jorge E, Yang Rui, Linkov Irina, Sowers Rebecca, DiResta Gene R, Gorlick Richard, Healey John H
Musculoskeletal Oncology Service, Department of Orthopaedic Surgery, Yong Loo Lin School of Medicine, National University of Singapore, 5, Lower Kent Ridge Road, Singapore 119074, Singapore.
J Orthop Res. 2008 Nov;26(11):1520-5. doi: 10.1002/jor.20633.
We have previously shown that osteosarcomas (OS) have states of increased interstitial fluid pressure (IFP), which correlate with increased proliferation and chemosensitivity. In this study, we hypothesized that constitutively raised IFP in OS regulates angiogenesis. Sixteen patients with the clinical diagnosis of OS underwent blood flow and IFP readings by the wick-in-needle method at the time and location of open biopsy. Vascularity was determined by capillary density in the biopsy specimens. We performed digital image analysis of immunohistochemical staining for CD31, VEGF-A, VEGF-C, and TPA on paraffin-embedded tissue blocks of the biopsy samples. Clinical results were validated in a pressurized cell culture system. Interstitial fluid pressures in the tumors (mean 33.5 +/- SD 17.2 mmHg) were significantly higher (p = 0.00001) than that in normal tissue (2.9 +/- 5.7 mmHg). Pressure readings were significantly higher in low vascularity tumors compared to high vascularity tumors (p < 0.001). In the OS cell lines, growth in a pressurized environment was associated with VEGF-A downregulation, VEGF-C upregulation, and TPA upregulation. The reverse was seen in the OB cell line. Growth in the HUVEC cell line was not significantly inhibited in a pressurized environment. Immunohistochemical assessment for VEGF-A (p = 0.01), VEGF-C (p = 0.008), and TPA (p = 0.0001) translation were consistent with the findings on PCR. Our data suggests that some molecules in angiogenesis are regulated by changes in IFP.
我们之前已经表明，骨肉瘤（OS）存在间质液压力（IFP）升高的状态，这与增殖增加和化学敏感性增加相关。在本研究中，我们假设OS中持续升高的IFP调节血管生成。16例临床诊断为OS的患者在开放活检的时间和部位通过针芯法进行血流和IFP读数。通过活检标本中的毛细血管密度确定血管生成情况。我们对活检样本石蜡包埋组织块上的CD31、VEGF-A、VEGF-C和TPA进行免疫组织化学染色的数字图像分析。临床结果在加压细胞培养系统中得到验证。肿瘤中的间质液压力（平均33.5±标准差17.2 mmHg）显著高于正常组织（2.9±5.7 mmHg）（p = 0.00001）。与高血管生成肿瘤相比，低血管生成肿瘤的压力读数显著更高（p < 0.001）。在OS细胞系中，加压环境下的生长与VEGF-A下调、VEGF-C上调和TPA上调相关。在OB细胞系中则观察到相反情况。在加压环境下，HUVEC细胞系的生长未受到显著抑制。VEGF-A（p = 0.01）、VEGF-C（p = 0.008）和TPA（p = 0.0001）翻译的免疫组织化学评估结果与PCR结果一致。我们的数据表明，血管生成中的一些分子受IFP变化的调节。
