【作者】 张波；

【导师】 郝进；

【作者基本信息】 重庆医科大学 ， 皮肤病与性病学， 2010， 硕士

【摘要】 蕈样肉芽肿(Mycosis fungoides,MF)是低度恶性皮肤T细胞淋巴瘤,易复发,预后差,早期外用糖皮质激素(glucocorticoid,GC)是控制疾病发展最常用的治疗方法之一。雷公藤内酯醇(Triptolide,TP)和糖皮质激素是皮肤科疾病治疗的常用药物,具有抗炎和免疫抑制等多种活性,两者联合治疗重症皮炎、湿疹、银屑病等炎症性疾病疗效较好。糖皮质激素通过激活细胞内受体(Glucocorticoid receptor,GR)发挥作用,两者之间的结合具有专一性。研究证实,糖皮质激素调节肿瘤细胞代谢的生物学效应需通过其受体介导,从而在转录及翻译水平调节相关基因的表达。Caspase酶在肿瘤细胞凋亡过程中具有不可忽视的作用,其中Caspase-3更是处于关键位置,多数细胞凋亡均通过Caspase-3介导的信号途径。本文以蕈样肉芽肿hut-102细胞为研究对象,探讨雷公藤联合地塞米松(dexamethasone,DEX)对该细胞体外增殖、凋亡的影响,进而分析两者是否具有交互效应及可能机制。研究方法:MTT法检测细胞存活率;流式细胞术检测细胞凋亡率;蛋白印迹法检测糖皮质激素受体GR和凋亡相关蛋白Caspase-3的表达。研究结果:①不同浓度雷公藤(6.25、12.5、25 nm/L)和地塞米松(10-7、10-6、10-5 mol/L)对hut-102细胞均有增殖抑制作用,与时间、浓度相关;12.5 nm/L雷公藤联合不同浓度地塞米松,与单药组相比,细胞抑制率明显升高(P﹤0.01),且随地塞米松浓度增大而升高。②雷公藤和地塞米松均能诱导该细胞凋亡,联合组凋亡率明显高于单药组(P﹤0.01),呈交互协同效应。③10-5 mol/L地塞米松作用hut-102细胞后,GR表达降低(P﹤0.05),联合组(12.5 nm/L雷公藤+10-5 mol/L地塞米松)较地塞米松组GR表达升高、Caspase-3激活增强(P﹤0.05)。研究结论:雷公藤联合地塞米松可明显抑制hut-102细胞增殖,增强诱导凋亡,具有交互协同效应,其作用机制可能与GR表达上调、Caspase-3激活增强有关。更多还原

【Abstract】 Mycosis fungoides is the most common cutaneous T-cell lymphomas, a group of rare cancers that grow in the skin with high recurrence rate and poor prognosis. Treatments such as steroid creams during the early stage of mycosis fungoides concern the clinical prognosis of the patients. Triptolide and dexamethasone are common drugs for treatment of skin diseases, with anti-inflammation and immunosuppression activities. Combination of triptolide and dexamethasone has apparent curative effect on treatment for inflammatory diseases such as severe dermatitis, eczema and psoriasis.The cellular responses of glucocorticoids are achieved by specifically binding to its ligands. Glucocorticoids mainly regulates the biological effect of cellular metabolism by its ligands, and affects the expression of tumor related genes in the transcription and translation level. Caspase enzyme, especially Caspase-3, plays an important role in the cell apoptosisIn this study, we aimed to investigate the effect of triptolide combined with dexamethasone on proliferation and apoptosis of the mycosis fungoides hut-102 cells and the possible mechanisms.The viability of hut-102 cells was measured by MTT assay; the apoptotic rate of hut-102 cells was detected by flow cytometry. The expression levels of Glucocorticoid receptor (GR) and apoptosis-related protein Caspase-3 were determined by Western Blot analysis.MTT assays showed that different concentrations of triptolide or dexamethasone can effectively inhibit the proliferation of hut-102 cells in a dose and time-dependent manner. When triptolide (12.5 nm/L) was co-administered with dexamethasone, the inhibition rate increased along with the concentration of dexamethasone. And we observed positive cooperative inhibitory effects of triptolide and dexamethasone on the proliferation of hut-102 cells. Both triptolide and dexamethasone can independently promote apoptosis of the hut-102 cell. And the apoptotic rate in the combination group was higher than single group(P﹤0.05). Compared with the significantly decreased expression of Glucocorticoid receptor (GR) in hut-102 cells in dexamethasone group, the expression of GR and activated Caspase-3 increased in the combination group(P<0.05).The apoptosis of hut-102 cells induced by dexamethasone was enhanced by triptolide, which maybe connected with the increased expression of GR and activated Caspase-3 in hut-102 cells.更多还原