NOL8对口腔鳞状细胞癌细胞增殖、迁移及侵袭的影响

doi:10.19401/j.cnki.1007-3639.2023.01.005

摘要/Abstract

摘要：

背景与目的：口腔鳞状细胞癌（oral squamous cell carcinoma，OSCC）是头颈部鳞状细胞癌中最普遍的亚型，其发病机制尚不清楚。核仁蛋白8（nucleolar protein 8，NOL8）作为RNA结合蛋白（RNA-binding protein，RBP），在多种肿瘤的发生、发展中发挥关键作用，但其在OSCC中的作用尚不清楚，本研究旨在探讨NOL8在OSCC中的表达水平，并研究其对OSCC细胞增殖、迁移、侵袭和上皮-间充质转化（epithelial-mesenchymal transition，EMT）的影响。方法：利用基因表达谱交互分析2（gene expression profiling interactive analysis 2，GEPIA2）、肿瘤免疫评估资源（tumor immune estimation resource，TIMER）、阿拉巴马大学伯明翰分校癌症数据分析（the University of Alabama at Birmingham cancer data analysis portal，UALCAN）及RNA相互作用数据库（the encyclopedia of RNA interactomes，ENCORI）在线分析NOL8在头颈鳞癌组织中的表达；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NOL8在OSCC细胞中的mRNA表达水平。利用siRNA干扰技术下调NOL8在CAL-27细胞中的表达，形成NOL8敲低组（si-NOL8-1，si-NOL8-2）及阴性对照组；通过慢病毒转染技术感染CAL-27及HN6细胞过表达NOL8，形成NOL8过表达组及阴性对照组。分别通过细胞计数试剂盒-8（cell counting kit-8，CCK-8）实验、划痕愈合试验及transwell实验检测NOL8表达水平变化后对OSCC细胞增殖、迁移和侵袭的影响；采用蛋白质印迹法（Western blot）检测NOL8表达水平改变后对EMT相关基因E-钙黏蛋白（E-cadherin）、波形蛋白（vimentin）和N-钙黏蛋白（N-cadherin）表达的影响。利用裸鼠皮下移植瘤模型探究NOL8在体内对OSCC细胞增殖的影响。结果：GEPIA2、TIMER、UALCAN及ENCORI在线分析显示，与头颈鳞癌的癌旁正常组织相比，NOL8在头颈鳞癌组织中表达升高；RTFQ-PCR结果显示，与正常对照细胞相比，NOL8在OSCC细胞系中的mRNA表达显著上调。转染si-NOL8-1及si-NOL8-2的CAL-27细胞中NOL8的相对表达量显著低于阴性对照组；敲低NOL8表达后，CCK-8实验、划痕愈合试验及transwell实验结果显示，CAL-27细胞增殖能力、细胞迁移率和细胞侵袭数明显降低。NOL8过表达的CAL-27及HN6细胞中NOL8的相对表达量显著高于对照组；NOL8过表达组中CAL-27及HN6细胞增殖能力、细胞迁移率和细胞侵袭数均显著高于阴性对照组。Western blot结果显示，在CAL-27细胞中，与敲低对照组相比，敲低NOL8后E-cadherin表达升高，N-cadherin和vimentin表达降低；在CAL-27及HN6细胞中，与过表达对照组相比，过表达NOL8后E-cadherin表达下降，N-cadherin和vimentin表达升高。裸鼠皮下移植瘤模型实验发现，与NOL8对照组相比，NOL8过表达组的皮下移植瘤重量显著升高。结论：NOL8在OSCC中高表达，可促进OSCC细胞的增殖、迁移和侵袭，该作用可能与EMT过程有关。

关键词: 口腔鳞状细胞癌, 核仁蛋白8, 增殖, 迁移, 侵袭

Abstract:

Background and purpose: Oral squamous cell carcinoma (OSCC) is the most common subtype of head and neck squamous cell carcinoma (HNSCC), and its pathogenesis is unclear. Nucleolar protein 8 (NOL8), as one of the RNA-binding protein (RBP), plays a key role in the occurrence and development of many kinds of tumors, however its role in OSCC is not clear. This study aimed to investigate the expression level of NOL8 in OSCC and its effects on the proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) of OSCC. Methods: The expression of NOL8 in HNSCC was analyzed online by gene expression profiling interactive analysis 2 (GEPIA2), tumor immune estimation resource (TIMER), the University of Alabama at Birmingham cancer data analysis portal (UALCAN) and the encyclopedia of RNA interactomes (ENCORI). The mRNA expression level of NOL8 in OSCC cells was detected by real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR). siRNA interference technique was used to knock down the expression of NOL8 in CAL-27 cells to form NOL8 knockdown group (si-NOL8-1, si-NOL8-2) and negative control group. CAL-27 and HN6 cells were overexpressed with NOL8 by lentivirus transfection technique to form NOL8 overexpression group and negative control group. Cell counting kit-8 (CCK-8) assay, scratch healing assay and transwell assay were used to detect the effect of NOL8 expression on the proliferation, migration and invasion of OSCC cells. Western blot assay was used to detect the effect of NOL8 on the expression of EMT-related genes including E-cadherin, vimentin and N-cadherin. The effect of NOL8 on the proliferation of OSCC cells in vivo was examed by xenograft formation assays. Results: The online analysis of GEPIA2, TIMER, UALCAN and ENCORI showed that the expression of NOL8 was higher in HNSCC than in normal tissues, and the expression of NOL8 in OSCC was significantly higher than in normal control cells. The relative expression of NOL8 in CAL-27 cells transfected with si-NOL8-1 and si-NOL8-2 was significantly lower compared with the negative control group. The results of CCK-8 assay, scratch healing assay and transwell assay showed that the proliferative ability, cell migration rate and invasion number of CAL-27 cells were significantly decreased after knockdown of NOL8 expression. The relative expression of NOL8 in CAL-27 and HN6 cells transfected with NOL8 was significantly higher compared with the control group. The proliferative ability, cell migration rate and invasion number of CAL-27 and HN6 cells in the overexpression NOL8 group were significantly higher compared with the negative control group. The results of Western blot showed that in CAL-27 cells, the expression of E-cadherin increased and the expressions of N-cadherin and vimentin decreased after NOL8 knockdown, while in CAL-27 and HN6 cells, the expression of E-cadherin decreased and the expressions of N-cadherin and vimentin increased after NOL8 overexpression. The xenograft formation assays showed that the weight of tumor was significantly higher in NOL8 overexpression group than in NOL8 control group. Conclusion: NOL8 is highly expressed in OSCC and can promote the proliferation, migration and invasion of OSCC, which may be related to the process of EMT.

Key words: Oral squamous cell carcinoma, Nucleolar protein 8, Proliferation, Migration, Invasion

中图分类号:

R739.85

王笑笑, 陈曦, 李敏敏, 宋宁, 孙冬瑗, 蒋英英. NOL8对口腔鳞状细胞癌细胞增殖、迁移及侵袭的影响[J]. 中国癌症杂志, 2023, 33(1): 45-53.

WANG Xiaoxiao, CHEN Xi, LI Minmin, SONG Ning, SUN Dongyuan, JIANG Yingying. Effects of NOL8 on cell proliferation, migration and invasion of oral squamous cell carcinoma[J]. China Oncology, 2023, 33(1): 45-53.

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参考文献 20

[1]	CHEN W Q, ZHENG R S, BAADE P D, et al. Cancer statistics in China, 2015[J]. CA Cancer J Clin, 2016, 66(2): 115-132. doi: 10.3322/caac.21338
[2]	AUGUSTE A, JOACHIM C, DELOUMEAUX J, et al. Head and neck cancer risk factors in the French West Indies[J]. BMC Cancer, 2021, 21(1): 1071. doi: 10.1186/s12885-021-08787-4 pmid: 34592954
[3]	OOSTING S F, HADDAD R I. Best practice in systemic therapy for head and neck squamous cell carcinoma[J]. Front Oncol, 2019, 9: 815. doi: 10.3389/fonc.2019.00815 pmid: 31508372
[4]	SPECENIER P, VERMORKEN J B. Optimizing treatments for recurrent or metastatic head and neck squamous cell carcinoma[J]. Expert Rev Anticancer Ther, 2018, 18(9): 901-915. doi: 10.1080/14737140.2018.1493925
[5]	DU E, MAZUL A L, FARQUHAR D, et al. Long-term survival in head and neck cancer: impact of site, stage, smoking, and human papillomavirus status[J]. Laryngoscope, 2019, 129(11): 2506-2513. doi: 10.1002/lary.27807
[6]	GU S, HOU P J, LIU K, et al. NOL8, the binding protein for beta-catenin, promoted the growth and migration of prostate cancer cells[J]. Chem Biol Interact, 2018, 294: 40-47. doi: 10.1016/j.cbi.2018.08.019
[7]	MO J S, CHAE S C. microRNA 452 regulates ASB8, NOL8, and CDR2 expression in colorectal cancer cells[J]. Genes Genomics, 2021, 43(1): 33-41. doi: 10.1007/s13258-020-01016-5
[8]	JINAWATH N, FURUKAWA Y, NAKAMURA Y. Identification of NOL8, a nucleolar protein containing an RNA recognition motif (RRM), which was overexpressed in diffuse-type gastric cancer[J]. Cancer Sci, 2004, 95(5): 430-435. doi: 10.1111/j.1349-7006.2004.tb03227.x
[9]	LU Y J, YAN Y C, LI B W, et al. A novel prognostic model for oral squamous cell carcinoma: the functions and prognostic values of RNA-binding proteins[J]. Front Oncol, 2021, 11: 592614. doi: 10.3389/fonc.2021.592614
[10]	SEKIGUCHI T, HAYANO T, YANAGIDA M, et al. NOP132 is required for proper nucleolus localization of DEAD-box RNA helicase DDX47[J]. Nucleic Acids Res, 2006, 34(16): 4593-4608. pmid: 16963496
[11]	O’LEARY D A, SHARIF O, ANDERSON P, et al. Identification of small molecule and genetic modulators of AON-induced dystrophin exon skipping by high-throughput screening[J]. PLoS One, 2009, 4(12): e8348. doi: 10.1371/journal.pone.0008348
[12]	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
[13]	LI T W, FU J X, ZENG Z X, et al. TIMER2.0 for analysis of tumor-infiltrating immune cells[J]. Nucleic Acids Res, 2020, 48(W1): W509-W514. doi: 10.1093/nar/gkaa407
[14]	CHANDRASHEKAR D S, BASHEL B, BALASUBRAMANYA S A H, et al. UALCAN: a portal for facilitating tumor subgroup gene expression and survival analyses[J]. Neoplasia, 2017, 19(8): 649-658. doi: S1476-5586(17)30179-3 pmid: 28732212
[15]	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): D92-D97. doi: 10.1093/nar/gkt1248
[16]	HEDBERG M L, GOH G, CHIOSEA S I, et al. Genetic landscape of metastatic and recurrent head and neck squamous cell carcinoma[J]. J Clin Invest, 2016, 126(4): 1606. doi: 10.1172/JCI86862 pmid: 27035818
[17]	MASUDA K, KUWANO Y. Diverse roles of RNA-binding proteins in cancer traits and their implications in gastrointestinal cancers[J]. Wiley Interdiscip Rev RNA, 2019, 10(3): e1520.
[18]	LIU J W, LI H, SHEN S X, et al. Alternative splicing events implicated in carcinogenesis and prognosis of colorectal cancer[J]. J Cancer, 2018, 9(10): 1754-1764. doi: 10.7150/jca.24569 pmid: 29805701
[19]	MITTAL V. Epithelial mesenchymal transition in tumor metastasis[J]. Annu Rev Pathol, 2018, 13: 395-412. doi: 10.1146/annurev-pathol-020117-043854 pmid: 29414248
[20]	周锦翰, 刘传霞, 葛巍立, 等. 上皮-间充质转化在口腔鳞状细胞癌发生、发展中作用的研究进展[J]. 浙江医学, 2021, 43(20): 2258-2262.
	ZHOU J H, LIU C X, GE W L, et al. The role of epithelial mesenchymal transformation in the genesis and development of oral squamous cell carcinoma[J]. Zhejiang Med J, 2021, 43(20): 2258-2262.