Related Experiment Video
Updated: Nov 21, 2025
Author Spotlight: Unveiling the Role of TMOD3 in Platinum Resistance and Immune Infiltration in Ovarian Cancer
Published on: August 2, 2024
Circular RNA circ_0081001 knockdown enhances methotrexate sensitivity in osteosarcoma cells by regulating
Wei Wei1, Liefeng Ji2, Wanli Duan2
1Department of Orthopedics, Shaoxing Shangyu People's Hospital, No. 517 Civic Avenue, Baiguan Street, Shangyu District, Shaoxing, Zhejiang, 312300, China. parjpy@163.com.
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.
Insights
Knockdown of circ_0081001 enhances osteosarcoma chemoresistance by downregulating TGM2 via sponging miR-494-3p. This finding offers a novel mechanism for cancer therapy targeting circular RNAs.
Area of Science:
- Oncology
- Molecular Biology
- Biochemistry
Background:
- Circular RNAs (circRNAs) are implicated in cancer chemoresistance and tumorigenesis.
- Methotrexate (MTX) resistance is a significant challenge in osteosarcoma (OS) treatment.
Purpose of the Study:
- To investigate the role of circ_0081001 in MTX resistance in osteosarcoma.
- To elucidate the molecular mechanism underlying circ_0081001's function in OS chemoresistance.
Main Methods:
- Quantitative real-time PCR (qRT-PCR) for gene expression analysis.
- Cell viability, apoptosis, migration, and invasion assays (CCK-8, flow cytometry, Transwell).
- Western blot, bioinformatics, dual-luciferase reporter assays, and in vivo xenograft models.
Main Results:
- Circ_0081001 and TGM2 were upregulated, while miR-494-3p was downregulated in MTX-resistant OS.
- Circ_0081001 knockdown increased MTX sensitivity by promoting apoptosis and inhibiting metastasis.
- Circ_0081001 acts as a molecular sponge for miR-494-3p, upregulating TGM2.
Conclusions:
- Circ_0081001 knockdown enhances OS MTX sensitivity by downregulating TGM2 through miR-494-3p sponging.
- This study reveals a novel regulatory mechanism for OS chemoresistance.
- Circ_0081001 presents a potential therapeutic target for circRNA-based OS treatment.
Related Concept Videos
01:22MicroRNAs
01:22MicroRNAs
02:15Experimental RNAi
03:03mTOR Signaling and Cancer Progression
The mTOR pathway or the...