Hypoxia accelerates the progression of angiosarcoma through the regulation of angiosarcoma cells and tumor microenvironment

Background

Angiosarcoma is a rare malignant tumor with a poor prognosis. It is known that hypoxic condition activates tumor progression in several cancers. Additionally, hypoxic tumor microenvironment accelerates immune escape. However, the presence and significance of hypoxia in angiosarcoma has not been adequately investigated.

花旗松素在Caco-2细胞模型中吸收转运机制及其抗炎活性研究

目的制备花旗松素单体并测定花旗松素在不同介质中的表观油水分配系数,研究其在结肠癌Caco-2细胞模型中吸收转运机制。方法酶解法制备花旗松素,采用高效液相色谱法测定花旗松素在37℃、不同pH值缓冲盐溶液和水中的饱和溶解度,通过油水分配系数计算公式得花旗松素表观油水分配系数;CCK-8实验考察花旗松素在Caco-2细胞中的安全浓度范围,再利用Caco-2细胞单层模型研究其双侧跨膜吸收转运机制;CCK-8实验考察花旗松素在人脐血管内皮细胞HDMEC细胞中的安全浓度范围,采用脂多糖诱导的HDMEC细胞建立炎症模型,用花旗松素进行干预,乳酸脱氢酶(LDH)试剂盒检测LDH的活力。结果花旗松素在不同溶剂中的lgP分别为0.29(0.1 mol/L盐酸)、0.48(pH 2.0)、0.46(pH 5.8)、0.34(pH 6.8)、0.26(pH 7.4)、0.38(水);花旗松素质量浓度在50～500μg/mL对Caco-2细胞无明显毒性作用;不同质量浓度花旗松素在Caco-2单层细胞模型中的转运具有时间依赖性,不同质量浓度花旗松素双侧转运P_app值无显著性差异,且均小于1×...     

Endostatin inhibits angiogenesis by stabilization of newly formed endothelial tubes

Endostatin decreased vascular endothelial growth factor (VEGF)-induced formation of endothelial tubes and microvessels sprouting from aortic rings and blocked their network. After cessation of treatment, the survival time of endostatin plus VEGF-treated tubes was approximately doubled in comparison to VEGF alone. Endostatin antibody blocked VEGF-induced endothelial tube formation and disrupted existing tubes. Endostatin immunostaining was localized between endothelium and basement membrane and in inter-endothelial junctions of new, but not of quiescent, blood vessels. In tumors grown in SCID mice, endostatin immunostaining was stronger accompanying blood vessel maturation and was significantly prominent in vessels of tumor marginal zone where angiogenesis is highly active. These data indicate a new antiangiogenic action of endostatin stabilizing and maturating endothelial tubes of newly formed blood vessels. Thus, strategies accelerating vascular stabilization and maturation could be promising in tumor therapy. This revised version was published online in June 2006 with corrections to the Cover Date.