Studies on the proliferation and metastasis formation of human osteosarcomas

在这4年中，我们对人骨肉瘤的增殖和转移形成进行了实验和临床研究。结果：(1)在裸鼠身上建立了3个可移植的人骨肉瘤，并在体外培养了1个人骨肉瘤细胞系。(2)含有可检测到的c-菌原体的人骨肉瘤在裸鼠中生长更快。c-fos - m RNA水平在人骨肉瘤中升高，在裸鼠中表现出高自发性肺转移率。(3) ras-癌基因激活小鼠成骨细胞样细胞系的病灶形成，而p53抑制其形成。(4)体外建立人成骨细胞系。1alpha25 (OH) _2D_3诱导碱性磷酸酶和骨钙素的表达，而TGFbeta_1降低这两种成骨性质的表达。(5)建立了两种针对人骨肉瘤相关抗原的单克隆抗体（mab），对人骨肉瘤具有高度特异性。这些单克隆抗体可能对骨恶性肿瘤的诊断有用。(6)分析了多药耐药基因-1 （MDR-1）的存在与人骨肉瘤预后的关系。含有MDR-1的骨肉瘤预后明显较差。(7)针对从人骨中纯化的两种蛋白，制备了人骨BGP和骨唾液蛋白II特异性单克隆抗体。这些MAsb有望成为人类成骨肿瘤免疫组织化学诊断的有用工具。(8)我们研究了β _1整合素家族成员和细胞外基质配体在骨肉瘤组织中的表达。原发性骨肉瘤通过α _4和α _1整合素的α _5亚基与纤维连接蛋白密切相互作用。

We have carried out experimental and clinical studies on the proliferation and metastasis formation of human osteosarcomas in these 4 years. Results we obtained are as follows : (1) We established three transplantable human osteosarcomas on to nude mice, and one cell line derived from human osteosarcoma in vitro. (2) Human osteosarcomas containing detectable c-myctranscripts grew more rapidly in nude mice. The level of c-fos m RNA was increased in human osteosarcomas showing high rate of spontaneous lung metastasis in nude mice. (3) Focus formations of murine osteoblastoid cell line was activated by ras-oncogene, while p53 suppressed them. (4) We established a human osteoblastoid cell line in vitro. 1alpha25 (OH) _2D_3 induced the expression of alkaline phosphatase and osteocalcin, while TGFbeta_1 reduced the expression of both osteoblastic properties. (5) We established two monoclonal antibodies (MAbs) against human osteosarcoma associated antigen which were highly specific for human osteosarcomas. Those MAbs were potentially useful for diagnosis of bone malignancy. (6) We analyzed the relationship between the prognosis of human osteosarcomas and the existence of multidrug resistance gene-1 (MDR-1). Osteosarcoma contaning MDR-1 showed apparently poor prognosis. (7) MAbs specific for human BGP and Bone sialoprotein II were produced against both proteins purified from human bones. These MAsb are expected to be a useful tool for immunohistochemical diagnosis of human osteogenic tumors. (8) We studied the expression of the member of the beta_1 integrin family and extracellular matrix ligands in osteosarcoma tissues. Primary osteosarcomas closely interacted with fibronectin through alpha_4 and possibly alpha_5 subunits of the beta_1 integrin.