Circular RNA from Tyrosylprotein Sulfotransferase 2 Gene Inhibits Cisplatin Sensitivity in Head and Neck Squamous Cell Carcinoma by Sponging miR-770-5p and Interacting with Nucleolin

Tianqing Wang; Chuan Xin; Shiyu Zhang; Xin Tian; Yuting Hu; Ying Wang; Jiongke Wang; Ning Ji; Xin Zeng; Jing Li

doi:10.3390/cancers15225351

Circular RNA from Tyrosylprotein Sulfotransferase 2 Gene Inhibits Cisplatin Sensitivity in Head and Neck Squamous Cell Carcinoma by Sponging miR-770-5p and Interacting with Nucleolin

Cancers (Basel). 2023 Nov 9;15(22):5351. doi: 10.3390/cancers15225351.

Authors

Tianqing Wang¹, Chuan Xin^{1

2}, Shiyu Zhang¹, Xin Tian¹, Yuting Hu¹, Ying Wang¹, Jiongke Wang¹, Ning Ji¹, Xin Zeng¹, Jing Li¹

Affiliations

¹ State Key Laboratory of Oral Diseases & National Center for Stomatology, National Clinical Research Center for Oral Diseases, Research Unit of Oral Carcinogenesis and Management, Chinese Academy of Medical Sciences, West China Hospital of Stomatology, Sichuan University, Chengdu 610041, China.
² Key Laboratory of Oral Biomedical Research of Zhejiang Province, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Stomatology Hospital, Cancer Center of Zhejiang University, Hangzhou 310006, China.

Abstract

Chemoresistance poses a significant challenge in the treatment of advanced head and neck squamous cell cancer (HNSCC). The role and mechanism of circular RNAs (circRNAs) in HNSCC chemoresistance remain understudied. We conducted circRNA microarray analysis to identify differentially expressed circRNAs in HNSCC. The expression of circRNAs from the tyrosylprotein sulfotransferase 2 (TPST2) gene and miRNAs was evaluated through qPCR, while the circular structure of circTPST2 was verified using Sanger sequencing and RNase R. Through Western blotting, biotin-labeled RNA pulldown, RNA immunoprecipitation, mass spectrometry, and rescue experiments, we discovered miR-770-5p and nucleolin as downstream targets of circTPST2. Functional tests, including CCK8 assays and flow cytometry, assessed the chemoresistance ability of circTPST2, miR-770-5p, and Nucleolin. Additionally, FISH assays determined the subcellular localization of circTPST2, miR-770-5p, and Nucleolin. IHC staining was employed to detect circTPST2 and Nucleolin expression in HNSCC patients. circTPST2 expression was inversely correlated with cisplatin sensitivity in HNSCC cell lines. Remarkably, high circTPST2 expression correlated with lower overall survival rates in chemotherapeutic HNSCC patients. Mechanistically, circTPST2 reduced chemosensitivity through sponge-like adsorption of miR-770-5p and upregulation of the downstream protein Nucleolin in HNSCC cells. The TCGA database revealed improved prognosis for patients with low circTPST2 expression after chemotherapy. Moreover, analysis of HNSCC cohorts demonstrated better prognosis for patients with low Nucleolin protein expression after chemotherapy. We unveil circTPST2 as a circRNA associated with chemoresistance in HNSCC, suggesting its potential as a marker for selecting chemotherapy regimens in HNSCC patients. Further exploration of the downstream targets of circTPST2 advanced our understanding and improved treatment strategies for HNSCC.

Keywords: Nucleolin; circTPST2; cisplatin sensitivity; head and neck squamous cell cancer; miR-770-5p.

Abstract

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