Experimental study on new treatment strategy of retinoblastoma

本研究旨在通过靶向Sonic Hedgehog（Shh）信号开发治疗视网膜母细胞瘤的新策略。首先，进行免疫组织化学以检查Shh信号和细胞生长相关信号的状态。Shh、Smoothened Patched和Gli-1在视网膜母细胞瘤细胞中容易检测到。Rb和Erk-1也被观察到。本研究以视网膜母细胞瘤细胞株Y 79为研究对象，用环巴胺（cyclopamine）处理Y 79细胞，MTT法检测细胞增殖情况。虽然加入环巴胺似乎抑制了Y 79视网膜母细胞瘤细胞系的细胞增殖，但数据没有显示出统计学意义。我们发现，通过加入环巴胺阻断Shh信号抑制了在成纤维细胞层上培养的血管内皮细胞的新血管形成。最后，我们将Y 79细胞植入C57 BL/6小鼠的前房中。然而，这些细胞没有形成肿瘤生长，而是在前房角周围沉积。为建立视网膜母细胞瘤小鼠模型，还需进一步完善细胞植入技术。

The study was conducted for the purpose of development of a new strategy of treatment of retinoblastoma by targeting Sonic Hedgehog (Shh) signal. First, immunohistochemistry was carried out to examine the status of Shh signal and cell-growth related signals. Shh, Smoothened Patched and Gli-1 weere readily detected in retinoblastoma cells. Rb and Erk-1 was also observed. These findings suggest that Shh signal is active in retinoblastoma cells.A culture of a cell line established from retinoblastoma (Y79) was treated with cyclopamine and cell proliferation was assayed by using MTT assay. Although adding cyclopamine seemed to suppress cell proliferation of Y79 retinoblastome cell line, the data did not exhibit statistical significacy.Neovascularization is critical in tumor growth. We showed that blocking Shh signal by addition of cyclopamine inhibited neovascularization by cultured vascular endothelial cells cultured on the fibroblast layer.Finally, we implanted Y79 cells into the anterior chamber of a C57BL/6 mouse. However, the cells did not form tumor growth and settled arounf the anterior chamber angle. Further improvementof cell implantation is to be developed for the purpose of establishment of retinoblastoma mousemodel.