长链非编码RNA LINC00671对肝细胞肝癌生物学行为的影响及机制

doi:10.19401/j.cnki.1007-3639.2022.10.007

摘要/Abstract

摘要：

背景与目的：肝细胞肝癌（hepatocellular carcinoma，HCC）是全球常见的肿瘤之一，目前已证实长链非编码RNA（long non-coding RNA，lncRNA）参与HCC的发生、发展。近期有研究发现作为一种功能性的lncRNA，即长基因间非蛋白编码RNA 671（long intergenic non-protein coding RNA 671，LINC00671）可能是新的抑癌分子，但其在HCC中的作用及分子机制尚不清楚。本研究旨在探讨LINC00671在HCC中的作用及可能的分子机制。方法：通过GEPIA、starBase数据库分析LINC00671在HCC及正常肝组织中的表达及预后情况；采用实时荧光定量聚合酶链反应（real-time fluorescence quantitative polymerase chain reaction，RTFQ-PCR）检测LINC00671在不同HCC细胞系中的表达差异；再采用RNA荧光原位杂交（fluorescence in situ hybridization，FISH）实验观察LINC00671亚细胞定位。体外敲低或过表达LINC00671后，利用细胞计数试剂盒-8（cell counting kit-8，CCK-8）、流式细胞术、细胞划痕及transwell实验分别观察LINC00671对HCC细胞增殖、凋亡、迁移及侵袭的影响。随后通过生物信息学预测LINC00671作为细胞核内lncRNA的下游靶分子，starBase、GEPIA数据库分析LINC00671与靶分子c-myc的相关性并进行RTFQ-PCR及蛋白质印迹法（Western blot）验证。最后，通过甲基化DNA免疫共沉淀PCR（methylated DNA immunoprecipitation-PCR，MeDIP-PCR）观察LINC00671对靶基因启动子甲基化水平的影响。结果：数据库分析结果显示，LINC00671在HCC组织中明显下调且其高表达预示着较好的预后（P <0.05）；LINC00671在不同HCC细胞系中表达下调且存在表达差异；LINC00671主要分布于细胞核内。体外肿瘤细胞行为学实验发现，LINC00671可以明显抑制HCC细胞的增殖、迁移及侵袭能力（P<0.05），同时其对细胞凋亡具有显著促进作用（P<0.05）。生物信息学分析结果显示，LINC00671在核内与癌基因c-myc启动子区可能存在Hoogsteen配对，数据库结果比对显示，LINC00671与c-myc表达水平呈现显著负相关（P<0.05）；LINC00671可以显著下调c-myc表达（P<0.05）。MeDIP-PCR结果显示，LINC00671可以增加c-myc启动子甲基化水平（P<0.05）。结论：LINC00671可能通过介导c-myc启动子甲基化下调后者表达从而抑制HCC进展。

关键词: 肝细胞肝癌, LINC00671, c-myc

Abstract:

Background and purpose: Hepatocellular carcinoma (HCC) is one of the most common tumors in the world. Long non-coding RNA (lncRNA) is determined to be involved in the occurrence and development of HCC. Recent reports suggest that a novel lncRNA-LINC00671 may be a new tumor suppressor, however, its role and molecular mechanism in HCC remain uncertain. Current research aimed to discover the role of LINC00671 in HCC and its potential molecular mechanism. Methods: The expression and prognosis of LINC000671 in hepatocellular carcinoma tissues were analyzed by GEPIA and starBase database. The expression of LINC00671 in normal and hepatoma cell lines was detected by real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR). The subcellular localization of LINC00671 was observed by RNA fluorescence in situ hybridization (FISH). After knockdown or overexpression of LINC00671 in vitro, the effects of LINC00671 on the proliferation, apoptosis, migration and invasion of hepatoma cells were investigated by cell counting kit-8 (CCK-8), flow cytometry, wound healing and transwell assays. Subsequently, online bioinformatics prediction was conducted to identify the target gene of LINC00671. The correlation between LINC00671 and target molecule c-myc was analyzed by starBase and GEPIA database. And the regulation of LINC00671 on c-myc was verified by RTFQ-PCR and Western blot. The effect of LINC00671 on the methylation level of target gene promoter was tested by methylated DNA immunoprecipitation-PCR (MeDIP-PCR). Results: The results of online database analysis showed that LINC00671 was significantly downregulated in hepatocellular carcinoma, and its high expression predicted a better prognosis (P<0.05). LINC00671 was down regulated and differentially expressed in different hepatoma cell lines, and it was mainly located in the nucleus of hepatoma cells. The results of tumor behavior experiment in vitro indicated that LINC00671 could significantly inhibit the proliferation, migration and invasion of hepatoma cells (P<0.05), and remarkably enhanced the apoptotic rate (P<0.05). Bioinformatics results showed that LINC00671 might bind to c-myc promoter by Hoogsteen pairing in nucleus. The results from database revealed that LINC00671 was significantly negatively correlated with c-myc expression in HCC (P<0.05). LINC00671 could significantly suppress the expression of c-myc (P<0.05). The results of MeDIP-PCR suggested that LINC00671 could increase the methylation level of c-myc promoter (P<0.05). Conclusion: LINC00671 may downregulate the expression of c-myc by inducing the hypermethylation of c-myc promoter, so as to inhibit the progression of HCC.

Key words: Hepatocellular carcinoma, LINC00671, c-myc

中图分类号:

R735.7

郭涛, 宋宁, 孙玉琪, 田佳琪, 唐婕, 孙榕婍, 蒋英英. 长链非编码RNA LINC00671对肝细胞肝癌生物学行为的影响及机制[J]. 中国癌症杂志, 2022, 32(10): 990-999.

GUO Tao, SONG Ning, SUN Yuqi, TIAN Jiaqi, TANG Jie, SUN Rongqi, JIANG Yingying. Effect of long non-coding RNA LINC00671 on biological behavior of hepatocellular carcinoma and its mechanism[J]. China Oncology, 2022, 32(10): 990-999.

图/表 4

参考文献 23

[1]	SIEGEL R L, MILLER K D, FUCHS H E, et al. Cancer statistics, 2021[J]. CA A Cancer J Clin, 2021, 71(1): 7-33. doi: 10.3322/caac.21654
[2]	PETRICK J L, KELLY S P, ALTEKRUSE S F, et al. Future of hepatocellular carcinoma incidence in the United States forecast through 2030[J]. J Clin Oncol, 2016, 34(15): 1787-1794. doi: 10.1200/JCO.2015.64.7412 pmid: 27044939
[3]	HARTKE J, JOHNSON M, GHABRIL M. The diagnosis and treatment of hepatocellular carcinoma[J]. Semin Diagn Pathol, 2017, 34(2): 153-159. doi: S0740-2570(16)30117-4 pmid: 28108047
[4]	REBOUISSOU S, NAULT J C. Advances in molecular classification and precision oncology in hepatocellular carcinoma[J]. J Hepatol, 2020, 72(2): 215-229. doi: S0168-8278(19)30484-2 pmid: 31954487
[5]	BRIDGES M C, DAULAGALA A C, KOURTIDIS A. LNCcation: lncRNA localization and function[J]. J Cell Biol, 2021, 220(2): e202009045. doi: 10.1083/jcb.202009045
[6]	LANZAFAME M, BIANCO G, TERRACCIANO L M, et al. The role of long non-coding RNAs in hepatocarcinogenesis[J]. Int J Mol Sci, 2018, 19(3): E682.
[7]	QIU L P, TANG Q, LI G H, et al. Long non-coding RNAs as biomarkers and therapeutic targets: recent insights into hepatocellular carcinoma[J]. Life Sci, 2017, 191: 273-282. doi: S0024-3205(17)30511-8 pmid: 28987633
[8]	LI J H, LIU S, ZHOU H, et al. starBase v2.0: decoding miRNA-ceRNA, miRNA-ncRNA and protein-RNA interaction networks from large-scale CLIP-Seq data[J]. Nucleic Acids Res, 2014, 42(database issue): 92-97.
[9]	TANG Z F, LI C W, KANG B X, et al. GEPIA: a web server for cancer and normal gene expression profiling and interactive analyses[J]. Nucleic Acids Res, 2017, 45(W1): W98-W102. doi: 10.1093/nar/gkx247
[10]	TANG Z F, KANG B X, LI C W, et al. GEPIA2: an enhanced web server for large-scale expression profiling and interactive analysis[J]. Nucleic Acids Res, 2019, 47(W1): W556-W560. doi: 10.1093/nar/gkz430
[11]	MAS-PONTE D, CARLEVARO-FITA J, PALUMBO E, et al. LncATLAS database for subcellular localization of long noncoding RNAs[J]. RNA, 2017, 23(7): 1080-1087. doi: 10.1261/rna.060814.117
[12]	HE S, ZHANG H, LIU H H, et al. LongTarget: a tool to predict lncRNA DNA-binding motifs and binding sites via Hoogsteen base-pairing analysis[J]. Bioinformatics, 2015, 31(2): 178-186. doi: 10.1093/bioinformatics/btu643 pmid: 25262155
[13]	NAVARRO GONZALEZ J, ZWEIG A S, SPEIR M L, et al. The UCSC genome browser database: 2021 update[J]. Nucleic Acids Res, 2021, 49(D1): D1046-D1057. doi: 10.1093/nar/gkaa1070 pmid: 33221922
[14]	WU D M, ZHENG Z H, ZHANG Y B, et al. Down-regulated lncRNA DLX6-AS1 inhibits tumorigenesis through STAT3 signaling pathway by suppressing CADM1 promoter methylation in liver cancer stem cells[J]. J Exp Clin Cancer Res, 2019, 38(1): 237. doi: 10.1186/s13046-019-1239-3
[15]	LI D Z, HU X S, YU S J, et al. Silence of lncRNA MIAT-mediated inhibition of DLG3 promoter methylation suppresses breast cancer progression via the Hippo signaling pathway[J]. Cell Signal, 2020, 73: 109697. doi: 10.1016/j.cellsig.2020.109697
[16]	ZHANG B G, LI C F, SUN Z X. Long non-coding RNA LINC00346, LINC00578, LINC00673, LINC00671, LINC00261, and SNHG9 are novel prognostic markers for pancreatic cancer[J]. Am J Transl Res, 2018, 10(8): 2648-2658. pmid: 30210701
[17]	QU S B, NIU K W, WANG J L, et al. LINC00671 suppresses cell proliferation and metastasis in pancreatic cancer by inhibiting AKT and ERK signaling pathway[J]. Cancer Gene Ther, 2021, 28(3/4): 221-233. doi: 10.1038/s41417-020-00213-4
[18]	叶浩, 彭余胜, 冯淑涵, 等. 长非编码RNA LINC00671对胰腺癌细胞Panc-1增殖与侵袭的影响[J]. 中国临床药理学杂志, 2021, 37(16): 2159-2162.
	YE H, PENG Y S, FENG S H, et al. Effect of long non-coding RNA LINC00671 on the proliferation and invasion of pancreatic cancer Panc-1 cells[J]. Chin J Clin Pharmacol, 2021, 37(16): 2159-2162.
[19]	HUO N, CONG R, SUN Z J, et al. STAT3/LINC00671 axis regulates papillary thyroid tumor growth and metastasis via LDHA-mediated glycolysis[J]. Cell Death Dis, 2021, 12(9): 799. doi: 10.1038/s41419-021-04081-0 pmid: 34404767
[20]	JIN G, MI H Y, YE Y F, et al. LINC00671 inhibits renal cell cancer progression via regulating miR-221-5p/SOCS1 axis[J]. Am J Transl Res, 2021, 13(7): 7524-7537. pmid: 34377233
[21]	WADE M, WAHL G M. C-Myc, genome instability, and tumorigenesis: the devil is in the details[J]. Curr Top Microbiol Immunol, 2006, 302: 169-203. pmid: 16620029
[22]	CHIARUGI V, RUGGIERO M. Role of three cancer “master genes” p53, bcl2 and c-myc on the apoptotic process[J]. Tumori, 1996, 82(3): 205-209.
[23]	MOON H, PARK H, RO S W. C-myc-driven hepatocarcinogenesis[J]. Anticancer Res, 2021, 41(10): 4937-4946. doi: 10.21873/anticanres.15307 pmid: 34593441