Basic amd clinical study on differentiation induction of solid tumors with frequent metastasis

本研究的最终目的是利用生理活性物质诱导骨肉瘤等恶性实体瘤的分化。但在兽医学领域，特别是在日本，对肿瘤患者的临床方面，如存活率取决于治疗，并没有充分的研究。我们在东京大学医院见过各种各样的癌症患者，因此我们开始调查这些肿瘤患者的预后。在研究期间，我们对犬口腔和鼻腔肿瘤、肥大细胞肿瘤、猫乳腺大肿瘤的预后进行了综述并发表了一些原创论文。研究结果与国外文献基本一致，可作为我们进一步研究的参考数据。还尝试从动物自发肿瘤中建立肿瘤细胞系。在此期间，我们已经建立了另外两种犬骨肉瘤细胞，malanooma细胞和犬和猫乳腺肿瘤细胞。这些细胞对进一步研究诱导恶性肿瘤分化具有重要价值。以克隆的犬骨肉瘤细胞为研究对象，以维生素D、tgf - β和重组人骨形态发生蛋白-2 （rhBMP-2）作为诱导分化的生理物质。通过在培养基中添加这些物质，使ALP活性。ALp染色强度、骨钙素浓度、I型胶原浓度随着成骨细胞表型特征的增加而增加。这一结果提示骨肉瘤细胞必须被这些物质诱导到更高的分化阶段。维生素D和rhBMP-2的诱导效力高于tgf - β。通过在其他犬骨肉瘤细胞中添加维甲酸和维生素D衍生物也观察到分化，尽管结果仍处于初步阶段。还需要进一步的研究，包括体内和临床研究。

Final purpose of this study is to induce differentiation of malignant solid tumor like osteosarvoma by physiologically active substances. But in veterinary medicine especially in Japn, the clinical aspects to tumor patients such as survival rates depending on the treatments are not fully investigated. We have seen various cancer patients in our hospital of Univerdity of Tokyo, therefore we have statted to investigate the prognosis of these tumor patients.During the research period, we reported a review and some original papers on the prognosis of canine oral and nasal tumors, mast cell tumors, feline mammary grand tumors. The results were almost the same as described in foreign countries before, but can be used as reference data for our further reseaches.Establishment of tumor cell lines from spontaneous animal tumors were also tried. During this period, we have establishe two other canine osteosarcoma cells, malanoma cells and canine and feline mamary gland tumor cells. These cells could be quite valuable ones for the further reseaches of induction of differentiation of malignant tumors.Differentiation induction was investigated using cloned canine osteosarcoma cells and vitamine D,TFG-beta, and recombinant human bone morphogenetic protein-2 (rhBMP-2) as physiologic substance. By addition of these substances into the culture media, ALP activity. ALp staining strength, osteocalcin concentrations, and type I collagen concentrations, as the phenotypic characteristics of osteoblasts, increased. This result suggests that osteosarcoma cells must be induced higher differentiation stages by these substances. The potency of induction was higher in vitamine D and rhBMP-2 than in TGF-beta.Differentiation was also observed by addition of retinoic acids and vitamine D derivatives in other canine osteosarcoma cells, though the results were still preliminary. Further researches including in vivo and clinical studies must be needed.