miR-192调控的腺苷酸环化酶7在急性早幼粒白血病维甲酸耐药中的作用

Despite the good results of all-trans retinoic acid (ATRA) in acute promyelocytic leukemia (APL) therapy, some patients still had relapses and lost their sensitivity to ATRA. It was reported that the activity of adenylate cyclase (AC) played an indispensable role during retinoic acid(RA)-induced maturation of APL cells. Recently we found that the protein level of AC7 subtype in the RA-sensitive APL cell line NB4 was obviously higher than that in the RA-resistant subclone NB4-R1. By microarray and bioinformatics analysis, we predicted miR-192 as a candidate miRNA, which had an inverse relationship with the AC7 protein level in NB4 and NB4-R1 cells, probably pairing with the complementary sites in the 3’-UTR of AC7 mRNA. Accordingly we hypothesized that AC7 might be regulated by miR-192 at post-transcriptional level and could play an important role in RA resistance of APL cells. In this study, we would intensively explore the regulatory mechanism underlying the AC7 expression by miR-192 and the function of miR-192-mediated AC7 in RA-induced APL cell differentiation. This work will not only be of benefit to explore the mechanisms of RA resistance for APL cells, but also provide new biomarkers used in clinical diagnosis and treatment of relapsed APL.

全反式维甲酸（ATRA）治疗急性早幼粒白血病(APL)效果良好，但仅用维甲酸治疗相当数量的患者会复发并发生维甲酸耐药。研究表明，腺苷酸环化酶(AC)的活化对维甲酸诱导的APL细胞分化至关重要。前期实验我们发现，维甲酸耐药型APL细胞株NB4-R1中AC7亚型的蛋白水平明显低于对维甲酸敏感的APL细胞株NB4。microRNA芯片及生物信息学分析表明，APL细胞中miR-192的表达水平和AC7蛋白水平呈反相关性，且与AC7 mRNA 3'-UTR序列互补。为此我们提出假设：AC7蛋白水平可能受到miR-192转录后水平的调控，miR-192和AC7在APL细胞对维甲酸耐药的过程中可能发挥重要作用。本课题将深入研究miR-192对AC7的表达调控作用，阐明miR-192调控的AC7在APL细胞分化及维甲酸耐药中的作用，丰富维甲酸的耐药机制，为临床上诊断和治疗复发耐药的APL患者提供新的靶标。

该项目原计划为明确miR-192对腺苷酸环化酶7（AC7）的转录后调控作用；明确miR-192调控的AC7在全反式维甲酸（ATRA）诱导的急性早幼粒白血病（APL）细胞分化中发挥重要作用；以及探究miR-192和AC7在APL患者骨髓细胞中的表达。获得国家自然科学基金资助后，该项目进展基本符合预期，相关研究成果于2018年在SCI杂志《Biochemical and Biophysical Research Communications》上发表。.同时，我们还进行了非编码RNA（包括microRNA和长链非编码RNA）在肝细胞癌（HCC）发生发展过程中的作用机制研究。在microRNA（miRNA）和HCC的研究方面，我们发现miR-92b能够通过抑制Smad7从而促进HCC肿瘤的生长和转移（2016, Cell Death Disease）；miR-23b能够通过抑制ST7L的表达促进HCC细胞的增殖和侵袭（2017, Cell Death Disease）；以及miR-766能够通过抑制NR3C2的表达从而在HCC的发生发展过程中发挥癌基因的作用（2019, Faseb Journal）。在长链非编码RNA（lncRNA）和HCC的研究方面，我们阐明了lncRNA DANCR在肝癌组织和血浆中表达明显升高并且能够促进HCC肿瘤的生长和转移（2016，Anticancer Research）。我们的研究还表明lncRNA XIST能够结合并抑制miR-92b的表达进而影响HCC细胞的增殖和转移（2016, Cell Death Disease）。进一步的研究表明外周血单核细胞和粒细胞中XIST的表达能够作为HCC患者早期诊断的生物标志物（2017, Therapeutic advances in Medical Oncology）。.另外，我们的研究还阐明了转录因子YY1能够调控HDAC1的表达进而降低HCC细胞对HDAC抑制剂的敏感性（2017，Oncotarget）；我们的研究还表明敲低IFIT3的表达能够明显的抑制肝脏的缺血再灌注损伤（2018, International Immunopharmacology）。.通过本课题的研究，我们旨在阐明多种非编码RNA在APL及HCC发生发展中的表达及作用，这能为探索新的疾病诊断生物标志物和治疗靶点提供理论基础。