Establishment of in vivo model for angiogenesis in hematological malignancy and development of anti-angiogenic therapy.

血管生成在实体瘤的发生、侵袭和转移中起着关键作用。最近，血管生成在白血病和多发性骨髓瘤的病理中的作用已经被提出。本工作的目的是建立一个具有血管生成的人白血病模型，并进一步研究血管生成在人白血病中的意义。将照射（8戈伊）的人松质骨移植到NOD/SCID小鼠（hu-Bone小鼠）的皮下组织中。6个月后，不仅在移植的骨髓和骨中，而且在小鼠皮下组织周围观察到人微血管。将人白血病Raji细胞接种到这些hu-bone小鼠中。白血病细胞在接种后14天内广泛侵入移植的人骨髓，几天后进入小鼠骨髓和脊髓周围。白血病浸润的人骨狭窄区微血管密度较正常人骨狭窄区明显增高 ...更多信息 - 用正常人骨髓细胞或仅用盐水接种的骨小鼠。与白血病侵袭相关的微血管密度增加与骨供体的年龄或性别无关。RT-PCR检测培养的Raji细胞中血管内皮生长因子（VEGF）121、165、促血管生成素（Angiopoietin-1、Angiopoietin-2）和促血管生成素样因子（Angiopoietin-like factor，Ang-2）的mRNA水平。可溶性TIE 2-Fc嵌合蛋白抑制白血病细胞的侵袭和血管生成。同时，骨髓内皮细胞中磷脂酰肌醇-3激酶（p85 a）的表达增强，并有白血病细胞浸润。抑制p85 a信号传导导致骨髓中血管生成的损害。使用三胞体载体将Flt-1、FGF和Eph受体的显性阴性形式的基因转移到白血病细胞中，并检查白血病侵袭性的改变。提示白血病骨髓浸润的血管生成是通过白血病细胞产生的某些促血管生成因子诱导的。这种具有血管生成的人白血病模型可能有助于寻找新的治疗方法或进行药物的临床前试验。少

Angiogenesis plays a critical role in solid tumor development, invasion and metastasis. Recently, a role of angiogenesis in the pathology of leukemia and multiple myeloma has been suggested. The purpose of this work was to generate a model for human leukemia with human angiogenesis and then to study the meaning of angiogenesis in human leukemias. Human cancellous bones, which were irradiated (8 Gy), were transplanted into subcutaneous tissue of NOD/SCID mice (hu-Bone mice). Human microvessels were observed in not only the transplanted bone marrow and bone but also around murine subcutaneous tissues over six months. Human leukemic Raji cells were inoculated into these hu-bone mice. The leukemic cells invaded diffusely into the transplanted human bone marrow within 14 days after innoculation, several days later into murine bone marrow and around the spinal cord. The density of microvessels in human bone narrow with the leukemic infiltration elevated significantly as compared to one of hu … More -bone mice which were inoculated with normal human bone marrow cells or with saline only. The increased density of microvessels associated with leukemic invasion was independent in age or sex of bone donors. The mRNA of vascular endothelial growth factor(VEGF)121,165, angiopoietin-1,2 and angiopoietin-like factor were detected in cultured Raji cells using RT-PCR. Soluble TIE2-Fc chimeric protein inhibited the development of invasion of leukemic cells and angiogenesis. Futhermore the expression of phosphatidylinositol-3 Kinase(p85a) in endothelia of bone marrow which involved with leykemic cells was augmented. The inhibition of p85a signalling resulted impairments of angiogenesis in bone marrow. The gene transfer of dominant negative forms of receptors for Flt-1,FGF and Eph using a tricystronic vector into leukemic cells was done and the alteration of leukamic invasiveness is examined. These observation suggested the angiogenesis in bone marrow by human leukemic infiltration was induced via certain angiogenetic factors produced by leukemic cells. This model for human leukemia with human angiogenesis may be useful for to search novel therapies or to do preclinical tests of drugs. Less