本实验希望在细胞水平上筛选出RORα的激动剂，寻找可能具有抗肿瘤作用的潜在药物配体。 首先，通过与RORα已知激动剂结构式的比对，寻找具有相似结构的六种植物天然提取化合物。然后，采用MTT检测药物对细胞的生长活性影响，寻找合适的加药浓度和处理时间。最后，提取相应药物处理后细胞的总RNA，使用半定量RT-PCR和实时荧光定量Real-time PCR，进行RORα本身的基因表达量及其部分下游靶基因mRNA表达量差异的检测。 实验结果表明，常春藤皂苷元、刺囊酸、牛蒡子苷、异泽兰黄素在50μM浓度范围内对SW480细胞均没有毒性作用。7-羟基千金子二萜醇在5μM浓度范围内对SW480细胞没有毒性作用，而25-50μM浓度对其生长活性具有抑制作用。雷公藤红素对SW480细胞具有较为明显的活性抑制作用，并呈现剂量依赖性。使用无毒性的25nM和50nM雷公藤红素处理24h后，SW480细胞的RORα及其下游靶基因ApoC3、Baml1的表达量在25nM处理下基本无变化，在50nM处理下略有上调。 因此可以得出结论，雷公藤红素对人结直肠癌细胞系SW480具有较为显著的活性抑制作用，并且雷公藤红素能够引起RORα本身及其正向调控的下游靶基因ApoC3和Baml1的表达上调。雷公藤红素具有成为抗肿瘤药物配体的可能性。

In order to screening the agonist of RORα and finding a potential antineoplastic drug, The effects of 6 drugs that including Hederagenin, Echinocystic acid, Eupatilin, Arctiin, 7β-Hydroxylathyrol and Celastrol on human colon cancer cells SW480 were tested by MTT method. RT-PCR and Real-time PCR were used to detect gene expression of RORα and its downstream target genes ApoC3 and Baml1. I found that Hederagenin, Echinocystic acid, Eupatilin and Arctiin do not affect the SW480 cells growth activity under 50μM, and 7β-Hydroxylathyrol has cytostatic activity on SW480 cells between 5-50μM, and Celastrol has obviously inhibitory effect on the proliferation of SW480 cells in a dose-dependent manner. Furthermore, the expression of RORα, ApoC3 and Baml1 are basically no change when SW480 cells were treated with Celastrol in 25μM, but up-regulated in 50μM. It comes to the conclusion that Celastrol could slightly trigger the expression of RORα and some of its downstream target genes. But Celastrol is really the ligand which binding to its LBD directly of RORα or not needs further study.