Circular RNA Circ_0081001 Knockdown Enhances Methotrexate Sensitivity in Osteosarcoma Cells by Regulating MiR-494-3p/TGM2 Axis
Overview
Authors
Affiliations
Background: Circular RNAs (circRNAs) have been shown to participate in the chemoresistance and tumorigenesis of multiple cancers. The purpose of this research was to investigate the function of circ_0081001 in methotrexate (MTX) resistance of osteosarcoma (OS) and its potential molecular mechanism.
Methods: The expression of circ_0081001, cytochrome P450 family 51 subfamily A member 1 (CYP51A1), and miR-494-3p was detected by qRT-PCR. Cell viability, apoptosis, migration, and invasion were evaluated by Cell Counting Kit-8 (CCK-8) assay, flow cytometry, and transwell assay, respectively. Western blot (WB) assay was used to measure the protein levels of cleaved-caspase3 (cleaved-casp3), E-cadherin, N-cadherin, and transglutaminase-2 (TGM2). The interaction between miR-494-3p and circ_0081001 or TGM2 was predicted by bioinformatics analysis and verified using the dual-luciferase reporter assay. The mice xenograft model was established to investigate the roles of circ_0081001 in MTX resistance of OS in vivo.
Results: Circ_0081001 and TGM2 were upregulated, and miR-494-3p was downregulated in MTX-resistant OS tissues and cells. Moreover, circ_0081001 interference enhanced cell sensitivity to MTX through promoting apoptosis and inhibiting cell viability and metastasis in vitro. Furthermore, circ_0081001 was identified as a molecular sponge of miR-494-3p to upregulate TGM2 level. In addition, circ_0081001 knockdown inhibited MTX resistance via upregulating miR-494-3p and downregulating TGM2. Besides, circ_0081001 downregulation improved MTX sensitivity of OS in vivo.
Conclusion: Knockdown of circ_0081001 enhanced MTX sensitivity of OS cells through downregulating TGM2 by sponging miR-494-3p, elucidating a novel regulatory mechanism for chemoresistance of OS and providing a potential circRNA-targeted therapy for OS.
Research progress of circRNAs in bone-related diseases.
Hua X, Yu L, Zhu H, Zhu Y, Fan G, Zhou G Front Oncol. 2025; 15:1481322.
PMID: 39931083 PMC: 11807992. DOI: 10.3389/fonc.2025.1481322.
Tang Y, He Y, Wu L Pharmgenomics Pers Med. 2024; 17:511-520.
PMID: 39588535 PMC: 11586481. DOI: 10.2147/PGPM.S473702.
Emerging roles of CircRNA-miRNA networks in cancer development and therapeutic response.
Hashemi M, Khosroshahi E, Daneii P, Hassanpoor A, Eslami M, Koohpar Z Noncoding RNA Res. 2024; 10:98-115.
PMID: 39351450 PMC: 11440256. DOI: 10.1016/j.ncrna.2024.09.006.
Osteosarcoma in a ceRNET perspective.
Mosca N, Alessio N, Di Paola A, Marrapodi M, Galderisi U, Russo A J Biomed Sci. 2024; 31(1):59.
PMID: 38835012 PMC: 11151680. DOI: 10.1186/s12929-024-01049-y.
Role of microRNA-494 in tumor progression.
Maharati A, Akhlaghipour I, Taghehchian N, Yazdi Z, Moghbeli M Am J Transl Res. 2023; 15(11):6342-6361.
PMID: 38074823 PMC: 10703645.