-
长链非编码RNA(long non-coding RNA,lncRNA)是一类长度超过200个核苷酸的RNA分子,虽然大多数lncRNA的功能尚不清楚,但近年来已有越来越多的lncRNA的功能得到鉴定[1]。最近的研究结果表明,lncRNA具有稳定的二级结构,可作为多种肿瘤的外周生物标志物[2]。它们在很大程度上参与细胞在转录、转录后和表观遗传水平上对基因表达的调节[3],并能通过不同机制调节细胞功能[4],例如:调节染色质动态,基因表达,细胞的生长、分化和发育[5-6]。lncRNA的表达及突变能促进肿瘤的发生和转移,由于其在多种组织中的全基因组表达模式和组织表达特异性,lncRNA有望成为新的肿瘤生物标志物和治疗靶点[7]。同源异型盒基因转录的反义基因间RNA(homeobox gene anti-sense intergenic RNA,HOTAIR)是研究最深入的lncRNA之一,其来源于染色体12q13.13上同源异型盒基因 C11和同源异型盒基因 C12之间的同源异型盒基因 C反义链的转录,是第一个被发现具有反式调节功能的lncRNA[8-9]。一些研究结果表明,HOTAIR在不同类型的肿瘤中表达失调,例如:乳腺癌、非小细胞肺癌、肝细胞癌、胃肠道癌和结直肠癌等[4, 7]。并且,HOTAIR参与了多种与肿瘤发生相关的过程,例如:影响细胞的迁移、增殖、凋亡、侵袭、攻击和转移[10]。鉴于这些重要功能,HOTAIR被用作人类各种肿瘤的潜在生物标志物[11]。
反义寡核苷酸(antisense oligonucleotides,ASON)是人工合成的长度为16~22个碱基的单链DNA类似物,通过沃森-克里克碱基配对与靶基因结合,可以导致核酸内切酶介导的转录本被敲除,以致靶基因沉默[12-13]。ASON可以高效、特异、不可逆地与靶基因互补结合,但标记后的探针能否进入胶质瘤细胞与HOTAIR特异性结合并影响细胞功能尚不明确。因此,本研究通过制备放射性核素标记的靶向lncRNA HOTAIR的ASON探针99Tcm-HYNIC-ASON[HYNIC为联肼尼克酰胺(hydrazino nicotinamide)],在细胞水平上研究其对人脑胶质瘤U87细胞增殖和迁移能力的影响,为HOTAIR在胶质瘤中的应用提供良好的理论支持。
99Tcm标记lncRNA HOTAIR反义寡核苷酸探针的制备及其对人脑胶质瘤U87细胞活性的影响
Preparation of 99Tcm labeled lncRNA HOTAIR antisense probe and its effect on the activity of human glioma U87 cells
-
摘要:
目的 制备新型的靶向长链非编码RNA(lncRNA)同源异型盒基因转录的反义基因间RNA(HOTAIR)的反义寡核苷酸(ASON)探针99Tcm-HYNIC-ASON(HYNIC为联肼尼克酰胺),探讨其对人脑胶质瘤U87细胞增殖和迁移能力的影响。 方法 设计并通过化学修饰合成HOTAIR的ASON,使用双功能螯合剂HYNIC偶联99Tcm并进行纯化。采用快速薄层层析(ITLC)法和琼脂糖凝胶电泳分别检测探针的标记率、放射化学纯度、体外稳定性及完整性。细胞摄取实验分为2组:Lipo-99Tcm-HYNIC-ASON组(转染组)和99Tcm-HYNIC-ASON组(未转染组),通过脂质体转染探针,测定人脑胶质瘤U87细胞对探针的摄取率;细胞计数试剂盒8(CCK-8)实验和细胞划痕实验分为3组:Lipo-99Tcm-HYNIC-ASON组(转染组)、99Tcm-HYNIC-ASON组(未转染组)、99Tcm-Control组(对照组),分别检测转染探针后细胞增殖和迁移能力的变化。2组间比较采用Student t检验,多组间比较采用单因素方差分析。 结果 99Tcm-HYNIC-ASON的标记率为(90.0±5.6)%。琼脂糖凝胶电泳结果显示,99Tcm与探针成功标记并且没有明显的降解,探针孵育12 h的放射化学纯度>80%。细胞摄取实验结果显示,转染后5 h,探针Lipo-99Tcm-HYNIC-ASON在人脑胶质瘤U87细胞中的摄取率最大(0.70%),与未转染组(0.16%)相比,差异有统计学意义(t=17.81,P<0.01)。CCK-8实验结果显示,转染探针Lipo-99Tcm-HYNIC-ASON能抑制人脑胶质瘤U87细胞的增殖能力,与未转染组相比,在各个时间点(1、2、3、4、5 d)的差异均有统计学意义(t=2.336~30.230, 均P<0.05)。细胞划痕实验结果显示,转染探针Lipo-99Tcm-HYNIC-ASON能抑制人脑胶质瘤U87细胞的迁移,3组细胞间隙融合率的差异有统计学意义(F=331.8,P<0.01),与未转染组相比,转染组细胞间隙融合率明显降低,且差异有统计学意义(60.0%对23.6%, t=51.54,P<0.01)。 结论 成功合成了靶向人脑胶质瘤lncRNA HOTAIR的探针99Tcm-HYNIC-ASON,该探针具有良好的体外稳定性和靶向结合能力,能够抑制人脑胶质瘤U87细胞的增殖和迁移。 Abstract:Objective To prepare a novel antisense oligonucleotides (ASON) probe, namely, 99Tcm-HYNIC-ASON (hydrazine nicotinamide (HYNIC)), targeting long non-coding RNA (lncRNA) homeobox gene anti-sense intergenic RNA (HOTAIR); and explore its effect on the proliferation and migration of human glioma U87 cells. Methods HOTAIR ASON was designed and synthesized by chemical modification, and the bifunctional chelating agent (HYNIC) was coupled with 99Tcm. Sephadex G25 was selected for separation and purification. The labeling rate, radiochemical purity, in vitro stability, and integrity of the probe were detected by instant thin-layer chromatography and agarose gel electrophoresis. Human glioma U87 cells were cultured for experimental use. The cell uptake assay was divided into two groups: Lipo-99Tcm-HYNIC-ASON (transfection group) and 99Tcm-HYNIC-ASON (non-transfection group). The probe was transfected by liposome to determine the probe uptake rate of human glioma U87 tumor cells. The cell counting kit-8 (CCK-8) assay and cell scratch assay were divided into three groups, namely, Lipo-99Tcm-HYNIC-ASON (transfection group), 99Tcm-HYNIC-ASON (non-transfection group), and 99Tcm-Control (control group), to detect the changes of cell proliferation and migration after transfection of probe. Student t-test was used for comparison between two groups, and one-way analysis of variance was used for multi-group comparison. Results The labeling rate of 99Tcm-HYNIC-ASON was (90.0±5.6)%. Gel electrophoresis results confirmed that 99Tcm and the probe were successfully labeled without evident degradation; the probe showed good stability and radiochemical purity >80% after being incubated for 12 h. The results of cell uptake assay showed that 5 h after liposome transfection, the maximum uptake rate of probe Lipo-99Tcm-HYNIC-ASON in human glioma U87 cells was 0.70%, which was significantly higher than that in the non-transfection group (0.16%; t=17.81, P<0.01). The results of CCK-8 assay showed that the transfection probe (Lipo-99Tcm-HYNIC-ASON) could inhibit the proliferation of human glioma U87 cells, and a significant difference was observed compared with the non-transfection group at 1, 2, 3, 4, 5 d (t=2.336–30.230, all P<0.05). The results of cell scratch assay showed that the transfection probe (Lipo-99Tcm-HYNIC-ASON) could inhibit the migration of human glioma U87 cells, and a significant difference was found in the intercellular fusion rate among the three groups (F=331.8, P<0.01). Compared with the non-transfection group (60.0%), the intercellular fusion rate in the transfection group was significantly lower (23.6%), and the difference was statistically significant (t=51.54, P<0.01). Conclusions The ASON probe targeting human glioma lncRNA HOTAIR has been successfully synthesized. The probe has good stability and targeted binding ability in vitro, which can inhibit the proliferation and migration of human glioma U87 cells. -
-
[1] Botti G, Scognamiglio G, Aquino G, et al. LncRNA HOTAIR in tumor microenvironment: what role?[J/OL]. Int J Mol Sci, 2019, 20(9): 2279[2020-11-10]. https://www.mdpi.com/1422-0067/20/9/2279. DOI: 10.3390/ijms20092279. [2] Tan SK, Pastori C, Penas C, et al. Serum long noncoding RNA HOTAIR as a novel diagnostic and prognostic biomarker in glioblastoma multiforme[J/OL]. Mol Cancer, 2018, 17(1): 74[2020-11-10]. https://molecular-cancer.biomedcentral.com/articles/10.1186/s12943-018-0822-0. DOI: 10.1186/s12943-018-0822-0. [3] Toy HI, Okmen D, Kontou PI, et al. HOTAIR as a prognostic predictor for diverse human cancers: a meta- and bioinformatics analysis[J/OL]. Cancers (Basel), 2019, 11(6): 778[2020-11-10]. https://www.mdpi.com/2072-6694/11/6/778. DOI: 10.3390/cancers11060778. [4] Hajjari M, Rahnama S. Association between snps of long non-coding rna HOTAIR and risk of different cancers[J/OL]. Front Genet, 2019, 10: 113[2020-11-10]. https://www.frontiersin.org/articles/10.3389/fgene.2019.00113/full. DOI: 10.3389/fgene.2019.00113. [5] Bhan A, Mandal SS. LncRNA HOTAIR: a master regulator of chromatin dynamics and cancer[J]. Biochim Biophys Acta, 2015, 1856(1): 151−164. DOI: 10.1016/j.bbcan.2015.07.001. [6] 张书琴, 崔明, 肖惠文, 等. 姜黄素对非小细胞肺癌细胞A549和H460放射敏感性的影响[J]. 国际放射医学核医学杂志, 2020, 44(3): 164−173. DOI: 10.3760/cma.j.cn121381−201912006−00005.
Zhang SQ, Cui M, Xiao HW, et al. Effects of curcumin on the radiosensitivity of non-small cell lung cancer A549 and H460 cells[J]. Int J Radiat Med Nucl Med, 2020, 44(3): 164−173. DOI: 10.3760/cma.j.cn121381−201912006−00005.[7] Bhan A, Soleimani M, Mandal SS. Long noncoding RNA and cancer: a new paradigm[J]. Cancer Res, 2017, 77(15): 3965−3981. DOI: 10.1158/0008-5472.CAN-16-2634. [8] Zhan S, Wang K, Xiang Q, et al. lncRNA HOTAIR upregulates autophagy to promote apoptosis and senescence of nucleus pulposus cells[J]. J Cell Physiol, 2020, 235(3): 2195−2208. DOI: 10.1002/jcp.29129. [9] Sun G, Wang YY, Zhang JX, et al. MiR-15b/HOTAIR/p53 form a regulatory loop that affects the growth of glioma cells[J]. J Cell Biochem, 2018, 119(6): 4540−4547. DOI: 10.1002/jcb.26591. [10] Yuan C, Ning Y, Pan Y. Emerging roles of HOTAIR in human cancer[J]. J Cell Biochem, 2020, 121(5/6): 3235−3247. DOI: 10.1002/jcb.29591. [11] Hajjari M, Salavaty A. HOTAIR: an oncogenic long non-coding RNA in different cancers[J]. Cancer Biol Med, 2015, 12(1): 1−9. DOI: 10.7497/j.issn.2095-3941.2015.0006. [12] Li MW, Ding X, Zhang YA, et al. Antisense oligonucleotides targeting lncRNA AC104041.1 induces antitumor activity through Wnt2B/β-catenin pathway in head and neck squamous cell carcinomas[J/OL]. Cell Death Dis, 2020, 11(8): 672[2020-11-10]. https://www.nature.com/articles/s41419-020-02820-3. DOI: 10.1038/s41419-020-02820-3. [13] Bushart D, Zalon AJ, Zhang H, et al. Antisense oligonucleotide therapy targeted against ATXN3 improves potassium channel-mediated purkinje neuron dysfunction in spinocerebellar ataxia type 3[J]. Cerebellum, 2021, 20(1): 41−53. DOI: 10.1007/s12311-020-01179-7. [14] Fu P, Shen BZ, Zhao CJ, et al. Molecular imaging of MDM2 messenger RNA with 99mTc-labeled antisense oligonucleotides in experimental human breast cancer xenografts[J]. J Nucl Med, 2010, 51(11): 1805−1812. DOI: 10.2967/jnumed.110.077982. [15] Fu P, Tian L, Cao XL, et al. Imaging CXCR4 expression with 99mTc-radiolabeled small-interference rna in experimental human breast cancer xenografts[J]. Mol Imaging Biol, 2016, 18(3): 353−359. DOI: 10.1007/s11307-015-0899-4. [16] Liu N, Ding HL, Vanderheyden JL, et al. Radiolabeling small RNA with technetium-99m for visualizing cellular delivery and mouse biodistribution[J]. Nucl Med Biol, 2007, 34(4): 399−404. DOI: 10.1016/j.nucmedbio.2007.02.006. [17] Kang L, Wang RF, Yan P, et al. Noninvasive visualization of RNA delivery with 99mTc-radiolabeled small-interference RNA in tumor xenografts[J]. J Nucl Med, 2010, 51(6): 978−986. DOI: 10.2967/jnumed.109.069906. [18] Zhou Q, Fu Z. In vitro and in vivo study of a novel liposome-mediated dual drug delivery for synergistic lung cancer therapy via oral administration[J]. Onco Targets Ther, 2020, 13: 12695−12703. DOI: 10.2147/OTT.S276837. [19] Almeida B, Nag OK, Rogers KE, et al. Recent progress in bioconjugation strategies for liposome-mediated drug delivery[J/OL]. Molecules. 2020, 25(23): 5672 [2020-11-10]. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7730700. DOI: 10.3390/molecules25235672. [20] Zhang M, Wang Q, Wan KW, et al. Liposome mediated-CYP1A1 gene silencing nanomedicine prepared using lipid film-coated proliposomes as a potential treatment strategy of lung cancer[J]. Int J Pharm, 2019, 566: 185−193. DOI: 10.1016/j.ijpharm.2019.04.078. [21] Kang L, Xu XJ, Ma C, et al. Optimized preparation of a 99mTc-radiolabeled probe for tracing microRNA[J]. Cell Biochem Biophys, 2015, 71(2): 905−912. DOI: 10.1007/s12013-014-0281-1.