miRNAs调控Prohibitin介导的阿霉素相关耐药机制在非霍奇金淋巴瘤中的研究

Much progress in conventional therapy for NHL have been achieved over the past decades, however, the chemoresistance and anticipated dose-related cardiotoxicity associated with Adriamycin (ADR) are critical obstacles to a successful outcome for many patients with intermediate and high grade NHL. In our former study, prohibitin (PHB), which might involve in chemoresistance as a mitochondrial protein, was demonstrated to be up-regulated in ADR-treated Raji cells. Prohibitin is a highly conserved mitochondrial protein that is thought to play roles in cell cycle control, differentiation, senescence, and antiproliferative activity. Furthermore, microRNAs have attracted more and more attention due to their important role in regulation expressions of their target-genes. Lactic acid-glycolic acid (PLGA) began as subjects absorption lines in vivo, screws and other implants of biodegradable material. PLGA have excellent advantages of biocompatibility, no immune response, safety and especially regulate the rate of polymer degradation by changing the ratio of two monomers and polymerization conditions in the body, further to control the drug release rate. So we considered the targeted PLGA sustained-release polymer particles carried with PHB associated gene might have broad application prospects and deserve to be investigated further. We aimed to explore the chemotheapy resistance mechanisms which mediated by PHB and relted microRNAs in NHL. Furthermore,potential use of PHB and associated miRNAs as targets to reverse drug resistance of NHl will also be investigated.In our study, a series techniques including miRNA chip, gene silence, bioinformatics, and FLGA sustained-release polymer particles will be combined to investigate the drug resistance mechanism of PHB regulated by miRNAs in NHL. Besides, we also plan to prepare targeted PLGA sustained-release polymer particles carring PHB associated gene and detected their basic physical properties, release characteristics in vitro. We hope to provide novel insight for the drug resistance associated with PHB and miRNAs, to raise therapeutic strategy for NHL.

在非霍奇金淋巴瘤（NHL）的治疗中，阿霉素作为经典的蒽环类抗生素被广泛应用，但阿霉素相关的耐药问题目前仍是导致NHL治疗失败的重要原因之一。PHB（prohibitin）是一类高度保守、广泛分布的线粒体蛋白，具有抗细胞凋亡、衰老和增殖的作用，我们前期试验已证实在阿霉素耐药组的Raji中，PHB表达增高，其可以作为一个共同的中间物而涉及多个生物过程。以miRNA作为切入点设计的基因药物有望为NHL治疗开辟新途径，而基因治疗目前面临着"靶向性差、副作用≥抗肿瘤效应的"瓶颈。我们设想联合miRNA芯片技术、基因沉默技术、生物信息学技术、PLGA微粒技术，探讨PHB受相关miRNAs调控的机制，评价PHB及相关miRNAs作为逆转阿霉素相关NHL化学耐药生物靶点的可靠性，为进一步探讨阿霉素相关NHL耐药机制提供理论及实验室基础。

非霍奇金淋巴瘤(Non-Hodgkin’s Lymphoma, NHL)是常见的起源于淋巴造血组织的恶性肿瘤，NHL的发生异质性、化学耐药及放射抵抗是导致治疗失败的主要原因。在NHL的治疗中，阿霉素作为经典的蒽环类抗生素被广泛应用，但阿霉素相关的耐药问题目前仍是导致NHL治疗失败的重要原因之一。PHB（prohibitin）是一类高度保守、广泛分布的线粒体蛋白，具有抗细胞凋亡、衰老和增殖的作用，且以miRNA作为切入点设计的基因药物有望为NHL治疗开辟新途径，本研究探讨了PHB受相关miRNAs调控的可能机制，评价PHB及相关miRNAs作为逆转阿霉素相关NHL化学耐药生物靶点的可靠性，为进一步探讨阿霉素相关NHL耐药机制提供了理论及实验室基础。.首先，以PHB为研究对象，探讨了PHB与Raji细胞耐药性的关系，研究发现：PHB可能与肿瘤尤其是NHL的发生及耐药有密切关系。PHB1可能与非霍奇金淋巴瘤耐药性有关，并通过介导TP53调控通路对抗肿瘤细胞的凋亡，导致肿瘤细胞耐药。PHB2与Cas-3与Raji细胞耐药性无密切关系，但其与非霍奇金淋巴瘤的耐药相关性还有待于其他耐药细胞系的检测。.其次，探讨了NHL细胞株中PHB及凋亡相关基因的表达，研究发现：在Raji细胞中存在PHB1、PHB2、TP53、Cas-3的表达升高，推断PHB在Raji细胞中高表达促进TP53的活性，并通过Cas依赖的途径促进Raji细胞的凋亡。然而，PHB基因在Raji细胞系中是否真正发挥促凋亡作用，其具体作用机制是否有TP53与Cas-3的参与，还需要进一步研究证实。 . 再次，进行了NHL细胞中microRNAs调控差异表达线粒体蛋白/基因的机制研究。研究发现：1、采用miRNA数据库（Walkman等）寻找与PHB相关的microRNAs序列，确定miR34a,miR34b、miR128作为PHB相关microRNA序列。2、miR-27a与miR-27b可能与非霍奇金淋巴瘤耐药性有关。综合研究就结果我们推测miR-27a与miR-27b可能靶向上调PHB1的表达，进一步下调TP53的活性从而对抗肿瘤细胞的凋亡，导致肿瘤细胞耐药。然而，其具体调控机制仍需要进一步的研究验证。miR-128与miR-34a与Raji细胞耐药性无密切关系，但其与非霍奇金淋巴瘤的耐药相关性还有待于