第二军医大学学报  2016, Vol. 37 Issue (10): 1270-1276   PDF    
长链非编码RNA在卵巢癌中的调控机制及研究进展
夏蕾蕾, 曾金凤, 徐明娟     
第二军医大学长海医院妇产科, 上海 200433
摘要: 长链非编码RNA(long noncoding RNA,lncRNA)是一类长度大于200个核苷酸的非编码RNA,它不仅参与维持细胞的正常生理功能,而且还在肿瘤的发生、发展中发挥重要作用。越来越多的研究表明,lncRNA是判断卵巢癌患者总生存期和无病生存期的独立预测因素,并且与卵巢癌的发生、发展有密切关系。本文对lncRNA与卵巢癌的关系进行了综述,以期为卵巢癌的预防、早期诊断和治疗提供思路和方法。
关键词: 长链非编码RNA     卵巢肿瘤     生存率     无病生存    
Long noncoding RNAs in ovarian cancer: progress in mechanisms and the emerging landscape
XIA Lei-lei, ZENG Jin-feng, XU Ming-juan     
Department of Obstetrics and Gynecology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China
Supported by Key Project of Shanghai Science and Technology Committee (12411950300), the "1255" Project of Changhai Hospital of Second Military Medical University (CH125510105), and the Joint Research Program for Management of Key Diseases by Shanghai Public Health System (2013ZYJB0201) .
Abstract: Long non-coding RNAs (lncRNAs) are a class of RNA molecules with more than 200 nucleotides that function as RNAs with little or no protein-coding capacity.They maintain the normal physiological functions of cells and are involved in the development and progression of the tumor. Growing research suggests that lncRNAs are independent prognostic factors affecting the overall survival and disease free survival of ovarian cancer and are closely related to the development and progression of tumors. This review summarized the recent progress in the relationship between lncRNAs and ovarian cancer, hoping to provide reference for the prevention, diagnosis, and therapy of ovarian cancer.
Key words: long non-coding RNAs     ovarian heoplasms     survival rate     disease-free survival    

卵巢癌是妇科肿瘤的头号杀手[1]。据统计,全球每年死于卵巢癌的女性多于10万;由于其发病隐匿、发展迅速、预后差,已成为导致女性死亡的第5位原因[2]。由于卵巢癌早期症状往往隐匿且不具有特异性,又缺乏早期诊断特异性指标,超过70%的初诊病例诊断时已达晚期[3]。随着手术方式的发展和化疗药物的使用,晚期卵巢癌患者的5年生存率仍然相对较低,始终维持在40%左右[4]。因此,明确新基因的功能与卵巢癌发生、发展的关系,对揭示卵巢癌发生与发展的分子机制、设计合理的治疗药物及判断预后有重要意义。近年研究发现长链非编码RNA(long noncoding RNA,lncRNA)在卵巢癌的发生、发展中具有重要作用,有望成为新型肿瘤标记物和肿瘤治疗的靶点。本文对lncRNA与卵巢癌的关系进行了综述,以期为卵巢癌的预防、早期诊断和治疗提供思路和方法。

1 lncRNA概述

lncRNA是一类长度大于200个核苷酸、缺乏明确开放阅读框的非编码[5-6]。既往认为lncRNA是没有生物功能的转录副产物,但随着技术的进展,越来越多的研究表明lncRNA不仅可以维持细胞的正常生理功能,同时还在肿瘤的发生、发展中起重要作用[7-8]。随着研究方法的不断进展,lncRNA的面纱正在被逐渐解开。研究发现lncRNA可以通过染色质重塑、蛋白甲基化和泛素化参与表观遗传调控,可以通过与转录因子或外源性DNA直接结合形成多聚转录调节复合体,还可以直接调控转录后加工、剪接、转运、翻译以及mRNA的降解过程[9-11]。H19是第一个在疾病中被发现的lncRNA,在胚胎发育过程中高表达,但是在出生后其表达被显著抑制[12]。目前有研究表明,H19在食管癌、乳腺癌和肝癌中重新表达,并且在胰腺癌中也有发现;H19的表达水平与肿瘤的侵袭和转移能力呈正相关,可能是通过拮抗let-7进而促进由高迁移率族蛋白A2 (high mobility group AT-hook2,HMGA-2)介导的上皮间质转化过程[13]。肝细胞癌上调的果蝇zeste基因增强子同源物2 (enhancer of zeste homolog 2,EZH2)相关长链非编码RNA (lncRNA-HEIH)通过与EZH2结合下调P21及其他细胞周期调控元件,促进细胞周期从G0期进入S期,诱导肝癌的发生;干扰lncRNA HEIH的表达可显著抑制肝癌细胞的增殖[14],提示lncRNA可能会成为肿瘤治疗的新靶点。

2 lncRNA与卵巢癌

随着基因芯片和高通量测序方法的进步,越来越多的lncRNA被发现。将卵巢癌中与肿瘤相关的10 207种lncRNA进行综合分析,最终发现有1 749种lncRNA的表达与卵巢癌有关[15],而进一步研究发现455种lncRNA在卵巢癌中的表达呈上调或下调趋势[16],如应激诱导非编码转录体5(long stress-induced non-coding transcript 5,LSINCT5)、 X失活特异性转录体(X inactive specific transcript,XIST)、 HOXA11-AS(HOXA11 antisense RNA)、HOX转录反义RNA(HOX transcript antisense RNA,HOTAIR)、浆细胞瘤转化迁移基因(plasmacytoma variant translocation 1,PVT1)、细胞周期激酶抑制因子4b(INK4b)位点的反义非编码RNA(antisense non-coding RNA in the INK4 locus,ANRIL)、人卵巢癌特异性转录体2(human ovarian cancer-specific transcript 2,HOST2)、1号染色体局部放大lncRNA(focally amplified lncRNA on chromosome 1,FAL1)、母系印迹表达基因3(maternally expressed gene 3,MEG3)等。

2.1 LSINCT5

LSINCT5定位于染色体5p15.33,是多聚核苷酸化的、负链的长链应激非编码转录体,位于细胞核内。Xu等[17]研究发现,LSINCT5在胃癌组织中相对于癌旁组织呈高表达,并且可以成为无病生存率的预测指标。Silva等[18]发现LSINCT5在卵巢癌及乳腺癌细胞系中高表达,抑制LSINCT5的表达将降低细胞的增殖能力;而通过芯片分析发现,抑制LSINCT5后816种基因发生了相应变化,其中有95种基因的表达量改变超过了2倍。尽管LSINCT5在卵巢癌中的研究较少,但现有研究提示其仍可能在卵巢癌中发挥重要作用。

2.2 XIST

XIST定位于染色体Xq13.2。雌性哺乳类动物通过X染色体失活机制抑制其中一条X染色体的转录,从而使基因数量在两性间达到平衡,该过程受到多个因素的调节,其中之一就是X染色体失活中心(X inactivation center,XIC)。XIC包含多个蛋白编码基因及非蛋白编码基因,而XIST则是第一个被发现的非蛋白编码基因。XIST仅在失活的X染色体中转录,其在X染色体的失活过程中发挥重要作用。XIST通过募集表观遗传调控因子Polycomb抑制性复合物,以顺式作用方式引发XIC,诱导基因沉默、参与细胞的增殖分化等过程。有研究表明,XIST与miR-152相互抑制,可能是因为位于同一RNA沉默复合体(RNA induced silencing complex,RISC)上的原因;敲除XIST后,miR-152发挥抑制肿瘤生长的作用[19]

Kawakami等[20]研究发现,XIST在卵巢癌细胞系中表达降低,并且与X染色体失活相关。Huang等[21]分析卵巢癌患者的预后发现,XIST表达量的减少与无进展间歇期相关(r=0.653,P=0.001);而在多个卵巢癌细胞系中,XIST的减少与紫杉醇耐药呈正相关。上述研究表明,XIST的表达可能成为卵巢癌患者化疗反应的潜在标记物。

2.3 ZNF300P1

ZNF300P1又称LOC134466,是人类锌指蛋白ZNF300的假基因,Gloss等[22]研究发现ZNF300P1在浆液性卵巢癌中表达下调,且其在81%的卵巢癌中呈甲基化状态。进一步研究发现,通过siRNA干扰ZNF300P1的转录可增加细胞的腹膜黏附能力[23],提示ZNF300P1参与了卵巢癌的腹腔及腹膜转移过程。

2.4 AB073614

Cheng等[24]通过分析GEO数据库(GSE18521和GSE38666)发现,AB073614在卵巢癌组织中过度表达,进一步比较75例患者的卵巢癌组织与癌旁组织发现AB073614的高表达与患者的5年生存率相关(17.2个月vs 30.0个月,P=0.025);在裸鼠成瘤实验中,抑制AB073614的表达可抑制肿瘤的生长,同时增殖、侵袭相关蛋白增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)、基质金属蛋白酶2(matrix metalloproteinase 2,MMP2)和MMP9的表达也降低;细胞学实验表明,抑制AB073614的表达可降低细胞的增殖能力,诱导细胞凋亡;而蛋白质印迹实验表明,AB073614可能通过ERK1/2和AKT介导的信号通路发挥作用[24]。提示 AB073614在卵巢癌的发生、发展过程中可能具有癌基因的作用。

2.5 HOXA11-AS

HOXA11-AS位于染色体7p15.2的HOXA区域,该区域包含多个编码基因 及非编码基因转录本。HOXA在正常卵巢上皮组织中不表达,而是在卵巢癌组织中重新表达,且具有亚型特异性。研究表明,HOXA9在浆液性卵巢癌、黏液性卵巢癌和子宫内膜样卵巢癌中表达;而HOXA10仅在黏液性卵巢癌和子宫内膜样卵巢癌中表达[25]。HOXA中包含HOXA10-AS、HOXA11-AS和HOTTIP这3种lncRNA。Richards等[26]对1 201例浆液性卵巢癌和2 009例对照组患者进行全基因组关联数据分析,发现HOXA11-AS的变异体rs17427875 (A>T)与浆液性卵巢癌的发病风险相关,且HOXA11-AS的表达在卵巢癌组织中下调;进一步研究发现,次要等位基因T与浆液性卵巢癌细胞的增殖、迁移、侵袭等功能相关,而等位基因A无相关影响,但具体机制尚不清楚。

2.6 H19

H19定位于染色体11p15.5,是目前研究最为广泛的lncRNA,其可调节染色质重构、DNA甲基化,也可作为miRNA的前体,并对组蛋白进行修饰,进而调控机体功能。正常情况下,H19仅在胎儿组织及成人肌纤维中存在。H19在肿瘤中呈高表达,并且在不同肿瘤中其作用也不尽相同,如H19在胃癌[27]、膀胱癌[28]等肿瘤中发挥癌基因作用,促进肿瘤生长和转移,而在肝癌[29]和前列腺癌[30]中发挥抑癌基因作用。研究发现,H19可通过多种方式参与肿瘤的进程。一方面H19通过与IGF2的印记作用调控肿瘤发展,另一方面,H19可通过其产物miR-675的介导在肿瘤中发挥作用[31]。在结直肠癌中miR-675可抑制抑癌基因RB的表达,从而促进肿瘤生长;而在胃癌中,H19可通过H19/miR-675/RUNX1基因调控肿瘤的发生、发展,也可上调ISM1,并通过miR-675下调CALN1的表达从而影响肿瘤的进展[32]。Yan等[13]发现H19可促进卵巢癌细胞的迁移和侵袭,其作用可能是通过调控靶基因let-7来实现的。此外,卵巢癌A2780耐药细胞株中H19的表达水平显著高于A2780敏感细胞株,这提示H19可能与卵巢癌耐药相关[33]

2.7 HOTAIR

HOTAIR定位于染色体12q13.13,是第一个被发现具有反式转录调控作用的lncRNA,仅存于哺乳动物中,共含有6个外显子,包括5个短的外显子及1个长的外显子[34]。HOTAIR在肝癌、胰腺癌、乳腺癌和胃癌等肿瘤中均表达上调,干扰其表达能够抑制肿瘤细胞的生长、侵袭,促进细胞凋亡。Wu等[35]发现HOTAIR具有分子骨架作用,可通过将PRC2和LSD1/CoREST/REST 复合物相互连接,使组蛋白H3第27位赖氨酸三甲基化和组蛋白H3第4位赖氨酸去二甲基化修饰,进而调控目的基因表达;HOTAIR的过度表达可以使多梳抑制复合物2(polycomb repressive complex 2,PRC2)在染色体上的定位发生变化,导致基因表达和染色质状态的改变,最终促进肿瘤转移。

Qiu等[36]研究发现HOTAIR在卵巢癌组织中呈高表达,且其表达量与肿瘤的病理分级、FIGO分期和淋巴结转移情况呈正相关;多变量分析结果显示HOTAIR是卵巢癌患者减少总生存期和无病生存期的独立预测因素。此外,在卵巢癌细胞SKOV3、HO8910-PM、HEY-A8中下调HOTAIR可显著抑制肿瘤细胞的迁移、侵袭;通过体内建立腹腔转移模型发现,抑制HOTAIR的表达后,裸鼠腹腔的转移灶明显减少[36]。进一步研究发现敲低HOTAIR可诱导细胞周期阻滞及细胞凋亡[37]。预示着HOTAIR有望成为卵巢癌诊断、判断预后的新标记物,并可能成为潜在的治疗靶点。

2.8 PVT1

PVT1定位于染色体8q24,长度大于300 kb。虽然PVT1不编码任何蛋白产物,但鉴于其位于Myc下游57 kb处[38-39],仍然引起了研究者的重视。PVT1与乳腺癌、肝癌、胰腺癌、前列腺癌、多发性骨髓瘤、高侵袭性B细胞淋巴瘤等均有密切关系。Colombo等[40]研究发现PVT1具有竞争性内源RNA的活性,并可调控Myc蛋白的稳定性。Liu等[41]通过分析与肿瘤联系较为密切的30种lncRNA,发现在联合使用卡铂与多西他赛治疗卵巢癌时,PVT1的表达量明显上升,且其上升程度与卡 铂和多西他赛的抗瘤活性呈正相关;上调或下调PVT1在卵巢癌细胞系的表达量时,P53及基质金属蛋白酶组织抑制因子1(TIMP1)的表达量也会发生相同改变,提示PVT1可促进P53及TIMP1的表达,表明PVT1可以作为卵巢癌药物疗效的评价指标。

2.9 ANRIL

ANRIL位于染色体9p21.3,与肿瘤、心血管疾病、糖尿病和阿尔茨海默病等存在密切关系,且可作为胃癌、肺癌、肝癌患者总生存期减少的独立预测因素。ANRIL可通过组蛋白甲基化修饰引起INK4A/ARF/INK4B基因的异常沉默,进而成为癌形成的启动因子[42-44]。ANRIL的作用机制主要为以下2个方面:(1)ANRIL与PRC2的核心亚基SUZ12作用,招募PRC2,介导H3K27三甲基化从而沉默p15的转录,促进肿瘤增殖[45];(2)ANRIL可与分子伴侣CBX7相互作用,招募PRC1到p16位点,通过组蛋白H3K27三甲基化抑制p16的表达,从而促进肿瘤生长[46]。Qiu等[47]研究发现ANRIL在高级别浆液性卵巢癌组织中呈高表达,且与肿瘤的病理分级、FIGO分期、淋巴结转移情况呈正相关。在卵巢癌细胞系中下调ANRIL的表达后,可以明显抑制癌细胞的迁移及侵袭,MMP3的表达量也明显下降,表明MMP3可能是ANRIL介导的下游关键基因;多元回归分析结果显示ANRIL是卵巢癌患者总生存期的独立预后因素,提示ANRIL可以作为卵巢癌的预后相关因素[47]

2.10 HOST2

HOST2定位于染色体10q23.1。2003年Rangle等[48]首次发现并命名了5个HOST家族基因,其中HOST1、HOST3、HOST4、HOST5均可编码蛋白,而HOST2包含多个拷贝的逆反录病毒相关序列,无开放阅读框,不能编码蛋白。HOST2很少表达于正常组织或者非卵巢癌组织,但其在4个主要的卵巢癌亚型中表达均上调,尤其是上皮性卵巢癌[48]。Gao等[38]发现在高级别浆液性卵巢癌中呈高表达的HOST2可促进卵巢癌细胞的增殖、迁移和侵袭,而进一步机制研究表明HOST2可作为miRNA海绵,与let-7b结合并抑制其功能,维持部分癌基因的活性,从而促进肿瘤生长[49]

2.11 FAL1

FAL1定位于染色体1q21.2。Hu等[50]通过对128例卵巢癌患者组织进行检测后发现FAL1,且其拷贝数改变与患者预后有显著关系;下调卵巢癌细胞系中FAL1的表达后,可明显抑制裸鼠体内肿瘤的生长;机制研究表明FAL1是通过与表观遗传抑制因子多梳基因BMI1(B cell specific moloneymurineleukemia virus insertion site 1)特异性结合,稳定BMI1蛋白,从而调控P21等下游基因的转录,进而抑制肿瘤细胞的生长。上述研究提示FAL1有望成为卵巢癌的新标记物和治疗卵巢癌的靶点。

2.12 MEG3

MEG3是第一个被发现的具有肿瘤抑制作用的lncRNA,其表达受表观遗传学的调控,存在异常的CpG岛甲基化。MEG3表达于多种正常组织中,但在肿瘤组织中低表达或不表达,其高表达可抑制癌细胞的生长,表明MEG3具有肿瘤抑制因子的作用[51]。Sheng等[52]对20例卵巢癌上皮组织与正常卵巢上皮组织进行分析,发现MEG3在卵巢癌组织呈低表达,并且通过甲基化特异性PCR(MSP)分析发现MEG3启动子区域CpG岛的甲基化可能是导致MEG3在卵巢癌中低表达的主要原因;体外实验证实MEG3可抑制卵巢癌的增殖,阻滞细胞周期,诱导细胞凋亡。

3 小 结

随着分子生物学的发展,关于卵巢癌中异常表达的lncRNA的研究越来越多,并且发现lncRNA在卵巢癌的发生、侵袭、转移中有重要作用,其中LSINCT5、XIST、HOTAIR、ANRIL等有望成为卵巢癌预后判断的分子标记物。尽管目前对lncRNA作用的分子机制研究有限,但lncRNA有可能成为临床卵巢癌治疗的理想靶点,值得进一步深入探讨。

参考文献
[1] JAYSON G C, KOHN E C, KITCHENER H C, LEDERMANN J A. Ovarian cancer[J]. Lancet , 2014, 384 :1376–1388. DOI:10.1016/S0140-6736(13)62146-7
[2] Cancer Genome Atlas Research Network. Integrated genomic analyses of ovarian carcinoma[J]. Nature , 2011, 474 :609–615. DOI:10.1038/nature10166
[3] 沈铿, 朗景和. 卵巢上皮性癌诊断和治疗中应注意的问题[J]. 中华妇产科杂志 , 2003, 38 :65–68.
[4] SIEGEL R L, MILLER K D, JEMAL A. Cancer statistics, 2016[J]. CA Cancer J Clin , 2016, 66 :7–30. DOI:10.3322/caac.v66.1
[5] RINN J L, CHANG H Y. Genome regulation by long noncoding RNAs[J]. Annu Rev Biochem , 2012, 81 :145–166. DOI:10.1146/annurev-biochem-051410-092902
[6] CECH T R, STEITZ J A. The noncoding RNA revolution-trashing old rules to forge new ones[J]. Cell , 2014, 157 :77–94. DOI:10.1016/j.cell.2014.03.008
[7] JWHITEHEADB J, PANDEYA G K, KANDURIA C. Regulation of the mammalian epigenome by long noncoding RNAs[J]. Biochim Biophys Acta , 2009, 1790 :936–947. DOI:10.1016/j.bbagen.2008.10.007
[8] LIA L, FENG T, LIAN Y, ZHANG G, GAREN A, SONG X. Role of human noncoding RNAs in the control of tumorigenesis[J]. Proc Natl Acad Sci USA , 2009, 106 :12956–12961. DOI:10.1073/pnas.0906005106
[9] ZHANG H, ZEITZ M J, WANG H, NIU B, GE S, LI W, et al. Long noncoding RNA-mediated intrachromosomal interactions promote imprinting at the Kcnq1 locus[J]. J Cell Biol , 2014, 204 :61–75. DOI:10.1083/jcb.201304152
[10] WANG X, ARAI S, SONG X, REICHART D, DU K, PASCUAL G, et al. Induced ncRNAs allosterically modify RNA-binding proteins in cis to inhibit transcription[J]. Nature , 2008, 454 :126–130. DOI:10.1038/nature06992
[11] YANG L, LIN C, LIU W, ZHANG J, OHGI K A, GRINSTEIN J D, et al. ncRNA- and Pc2-methylation-dependent gene relocation between nuclear structures mediates gene activation programs[J]. Cell , 2011, 147 :773–788. DOI:10.1016/j.cell.2011.08.054
[12] MONNIER P, MARTINET C, PONTIS J, STANCHEVA I, AIT-SI-ALI, DANDOLO L. H19 lncRNA controls gene expression of the Imprinted Gene Network by recruiting MBD1[J]. Proc Natl Acad Sci USA , 2013, 110 :20693–20698. DOI:10.1073/pnas.1310201110
[13] YAN L, ZHOU J, GAO Y, GHAZAL S, LU L, BELLONE S, et al. Regulation of tumor cell migration and invasion by the H19/let-7 axis is antagonized by metformin-induced DNA methylation[J]. Oncogene , 2015, 34 :3076–3084. DOI:10.1038/onc.2014.236
[14] YANG F, ZHANG L, HUO X S, YUAN J H, XU D, YUAN S X, et al. Long noncoding RNA high expression in hepatocellular carcinoma facilitates tumor growth through enhancer of zeste homolog 2 in humans[J]. Hepatology , 2011, 54 :1679–1689. DOI:10.1002/hep.24563
[15] DU Z, FEI T, VERHAAK R G, SU Z, ZHANG Y, BROWN M, et al. Integrative genomic analyses reveal clinically relevant long noncoding RNAs in human cancer[J]. Nat Struct Mol Biol , 2013, 20 :908–913. DOI:10.1038/nsmb.2591
[16] AKRAMI R, JACOBSEN A, HOELL J, SCHULTZ N, SANDER C, LARSSON E. Comprehensive analysis of long non-coding RNAs in ovarian cancer reveals global patterns and targeted DNA amplification[J/OL]. PLoS One, 2013, 8: e80306. doi: 10.1371/journal.pone.0080306
[17] XU M D, QI P, WENG W W, SHEN X H, NI S J, DONG L, et al. Long non-coding RNA LSINCT5 predicts negative prognosis and exhibits oncogenic activity in gastric cancer[J/OL]. Medicine (Baltimore), 2014, 93: e303. doi: 10.1097/MD. 0000000000000303
[18] SILVA J M, BOCZEK N J, BERRES M W, MA X, SMITH D I. LSINCT5 is over expressed in breast and ovarian cancer and affects cellular proliferation[J]. RNA Biol , 2011, 8 :496–505. DOI:10.4161/rna.8.3.14800
[19] YAO Y, MA J, XUE Y, WANG P, LI Z, LIU J, et al. Knockdown of long non-coding RNA XIST exerts tumor-suppressive functions in human glioblastoma stem cells by up-regulating miR-152[J]. Cancer Lett , 2015, 359 :75–86. DOI:10.1016/j.canlet.2014.12.051
[20] KAWAKAMI T, ZHANG C, TANIGUCHI T, KIM C J, OKADA Y, SUGIHARA H, et al. Characterization of loss-of-inactive X in Klinefelter syndrome and female-derived cancer cells[J]. Oncogene , 2004, 23 :6163–6169. DOI:10.1038/sj.onc.1207808
[21] HUANG K C, RAO P H, LAU C C, HEARD E, NG S K, BROWN C, et al. Relationship of XIST expression and responses of ovarian cancer to chemotherapy[J]. Mol Cancer Ther , 2002, 1 :769–776.
[22] GLOSS B S, PATTERSON K I, BARTON C A, GONZALEZ M, SCURRY J P, HACKER N F, et al. Integrative genome-wide expression and promoter DNA methylation profiling identifies a potential novel panel of ovarian cancer epigenetic biomarkers[J]. Cancer Lett , 2012, 318 :76–85. DOI:10.1016/j.canlet.2011.12.003
[23] GLOSS B, MORAN-JONES K, LIN V, GONZALEZ M, SCURRY J, HACKER N F, et al. ZNF300P1 encodes a lincRNA that regulates cell polarity and is epigenetically silenced in type Ⅱ epithelial ovarian cancer[J]. Mol Cancer , 2014, 13 :3.
[24] CHENG Z, GUO J, CHEN L, LUO N, YANG W, QU X. A long noncoding RNA AB073614 promotes tumorigenesis and predicts poor prognosis in ovarian cancer[J]. Oncotarget , 2015, 6 :25381–25389. DOI:10.18632/oncotarget
[25] CHENG W, LIU J, YOSHIDA H, ROSEN D, NAORA H. Lineage infidelity of epithelial ovarian cancers is controlled by HOX genes that specify regional identity in the reproductive tract[J]. Nat Med , 2005, 11 :531–537. DOI:10.1038/nm1230
[26] RICHARDS E J, PERMUTH-WEY J, LI Y, CHEN Y A, COPPOLA D, REID B M, et al. A functional variant in HOXA11-AS, a novel long non-coding RNA, inhibits the oncogenic phenotype of epithelial ovarian cancer[J]. Oncotarget , 2015, 6 :34745–34757.
[27] LI H, YU B Q. LI J F, SU L P, YAN M, ZHU Z G. Overexpression of lncRNA H19 enhances carcinogenesis and metastasis of gastric cancer[J]. Oncotarget , 2014 (5) :2318–2329.
[28] LUO M, LI Z W, WANG W, ZENG Y G, LIU Z H, QIU J X. Long non-coding RNA H19 increases bladder cancer metastasis by associating with EZH2 and inhibiting E-cadherin expression[J]. Cancer Lett , 2013, 333 :213–221. DOI:10.1016/j.canlet.2013.01.033
[29] LV J, MA L, CHEN X L, HUANG X H, WANG Q. Downregulation of LncRNAH19 and MiR-675 promotes migration and invasion of human hepatocellular carcinoma cells through AKT/GSK-3β/Cdc25A signaling pathway[J]. J Huazhong Univ Sci Technolog Med Sci , 2014, 34 :363–369. DOI:10.1007/s11596-014-1284-2
[30] ZHU M J, CHEN Q, LIU X, SUN Q, ZHAO X, DENG R. LncRNA H19/miR-675 axis represses prostate cancer metastasis by targeting TGFBI[J]. FEBS J , 2014, 281 :3766–3775. DOI:10.1111/febs.2014.281.issue-16
[31] GABORY A, RIPOCHE M A, LE DIGARCHER A, WATRIN F, ZIYYAT A, FORNÉ T, et al. H19 acts as a trans regulator of the imprinted gene network controlling growth in mice[J]. Development , 2009, 136 :3413–3421. DOI:10.1242/dev.036061
[32] TSANG W P, NG E K, NG S S, JIN H, YU J, SUNG J J, et al. Oncofetal H19-derived miR-675 regulates tumor suppressor RB in human colorectal cancer[J]. Carcinogenesis , 2010, 31 :350–358. DOI:10.1093/carcin/bgp181
[33] MATOUK I J, RAVEH E, ABU-LAIL R, MEZAN S, GILON M, GERSHTAIN E, et al. Oncofetal H19 RNA promotes tumor metastasis[J]. Biochim Biophys Acta , 2014, 1843 :1414–1426. DOI:10.1016/j.bbamcr.2014.03.023
[34] HE S, LIU S, ZHU H. The sequence, structure and evolutionary features of HOTAIR in mammals[J]. BMC Evol Biol , 2011, 11 :102. DOI:10.1186/1471-2148-11-102
[35] WU Y, ZHANG L, WANG Y, LI H, REN X, WEI F, et al. Long noncoding RNA HOTAIR involvement in cancer[J]. Tumour Biol , 2014, 35 :9531–9538. DOI:10.1007/s13277-014-2523-7
[36] QIU J J, LIN Y Y, YE L C, DING J X, FENG W W, JIN H, et al. Overexpression of long non-coding RNA HOTAIR predicts poor patient prognosis and promotes tumor metastasis in epithelial ovarian cancer[J]. Gynecol Oncol , 2014, 134 :121–128. DOI:10.1016/j.ygyno.2014.03.556
[37] QIU J J, WANG Y, DING J X, JIN H Y, YANG G, HUA K Q. The long non-coding RNA HOTAIR promotes the proliferation of serous ovarian cancer cells through the regulation of cell cycle arrest and apoptosis[J]. Exp Cell Res , 2015, 333 :238–248. DOI:10.1016/j.yexcr.2015.03.005
[38] GAO Y, MENG H, LIU S P, HU J J, ZHANG Y M, JIAO T T. LncRNA-HOST2 regulates cell biological behaviors in epithelial ovarian cancer through a mechanism involving microRNA let-7b[J]. Hum Mol Genet , 2015, 24 :841–852. DOI:10.1093/hmg/ddu502
[39] KHAITAN D, DINGER M E, MAZAR J, CRAWFORD J, SMITH M A, MATTICK J S, et al. The melanoma-upregulated long noncoding RNA SPRY4-IT1 modulates apoptosis and invasion[J]. Cancer Res , 2011, 71 :3852–3862. DOI:10.1158/0008-5472.CAN-10-4460
[40] COLOMBO T, FARINA L, MACINO G, PACI P. PVT1: a rising star among oncogenic long noncoding RNAs[J]. Biomed Res Int , 2015, 2015 :304208.
[41] LIU E, LIU Z, ZHOU Y. Carboplatin-docetaxel-induced activity against ovarian cancer is dependent on up-regulated lncRNA PVT1[J]. Int J Clin Exp Pathol , 2015, 8 :3803–3810.
[42] YU W, GIUS D, ONYANGO P, MULDOON-JACOBS K, KARP J, FEINBERG A P, et al. Epigenetic silencing of tumour suppressor gene p15 by its antisense RNA[J]. Nature , 2008, 451 :202–206. DOI:10.1038/nature06468
[43] EL MESSAOUDI-AUBERT S, NICHOLLS J, MAERTENS G N, BROOKES S, BERNSTEIN E, PETERS G. Role for the MOV10 RNA helicase in polycomb-mediated repression of the INK4a tumor suppressor[J]. Nat Struct Mol Biol , 2010, 17 :862–868. DOI:10.1038/nsmb.1824
[44] PASMANT E, LAURENDEAU I, HÉRON D, VIDAUD M, VIDAUD D, BIÈCHE I. Characterization of a germ-line deletion, including the entire INK4/ARF locus, in a melanoma-neural system tumor family: identification of ANRIL, an antisense noncoding RNA whose expression coclusters with ARF[J]. Cancer Res , 2007, 67 :3963–3699. DOI:10.1158/0008-5472.CAN-06-2004
[45] KOTAKE Y, NAKAGAWA T, KITAGAWA K, SUZUKI S, LIU N, KITAGAWA M, et al. Long non-coding RNA ANRIL is required for the PRC2 recruitment to and silencing of p15(INK4B) tumor suppressor gene[J]. Oncogene , 2011, 30 :1956–1962. DOI:10.1038/onc.2010.568
[46] YAP K L, LI S, MUÑOZ-CABELLO A M, RAGUZ S, ZENG L, MUJTABA S, et al. Molecular interplay of the noncoding RNA ANRIL and methylated histone H3 lysine 27 by polycomb CBX7 in transcriptional silencing of INK4a[J]. Mol Cell , 2010, 38 :662–674. DOI:10.1016/j.molcel.2010.03.021
[47] QIU J J, LIN Y Y, DING J X, FENG W W, JIN H Y, HUA K Q. Long non-coding RNA ANRIL predicts poor prognosis and promotes invasion/metastasis in serous ovarian cancer[J]. Int J Oncol , 2015, 46 :2497–2505.
[48] RANGEL L B, SHERMAN-BAUST C A, WERNYJ R P, SCHWARTZ D R, CHO K R, MORIN P J. Characterization of novel human ovarian cancer-specific transcripts (HOSTs) identified by serial analysis of gene expression[J]. Oncogene , 2003, 22 :7225–7232. DOI:10.1038/sj.onc.1207008
[49] GAO Y, MENG H, LIU S, HU J, ZHANG Y, JIAO T, et al. LncRNA-HOST2 regulates cell biological behaviors in epithelial ovarian cancer through a mechanism involving microRNA let-7b[J]. Hum Mol Genet , 2015, 24 :841–852. DOI:10.1093/hmg/ddu502
[50] HU X, FENG Y, ZHANG D, ZHAO S D, HU Z, GRESHOCK J, et al. A functional genomic approach identifies FAL1 as an oncogenic long noncoding RNA that associates with BMI1 and represses p21 expression in cancer[J]. Cancer Cell , 2014, 26 :344–357. DOI:10.1016/j.ccr.2014.07.009
[51] ZHANG X, ZHOU Y, MEHTA K R, DANILA D C, SCOLAVINO S, JOHNSON S R, et al. A pituitary-derived MEG3 isoform functions as a growth suppressor in tumor cells[J]. J Clin Endocrinol Metab , 2003, 88 :5119–5126. DOI:10.1210/jc.2003-030222
[52] SHENG X, LI J, YANG L, CHEN Z, ZHAO Q, TAN L, et al. Promoter hypermethylation influences the suppressive role of maternally expressed 3, a long non-coding RNA, in the development of epithelial ovarian cancer[J]. Oncol Rep , 2014, 32 :277–285.