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[MiR-300 inhibits invasion and metastasis of osteosarcoma cell MG63 by negatively regulating PTTG1]
1First Department of Joint Surgery, Affiliated Hospital of Weifang Medical College, Weifang Medical University, Weifang 26105, China.
Objective:
To investigate the effects of miR-300 and PTTG1 on osteosarcoma invasion and metastasis and explore the molecular mechanism of osteosarcoma invasion and metastasis.
Objective:
Western blot was used to detect the expression of PTTG1 in human osteoblasts hFOB1.19 and osteosarcoma cell MG63 and to detect the transfection efficiency of cells transfected with PTTG1-knockdown plasmid; Transwell invasion assay and CCK8 assay detected the effects of knockdown of PTTG1 and overexpression of miR-300 on the invasion and proliferation of osteosarcoma cell MG63. On-line prediction and screening of microRNAs (miRNAs) with complementary PTTG1 binding was conducted. qRT-PCR was performed to examine the expression of miR-300 in hFOB1.19 and MG63 cells, and Western blotting was used to detect the expression of PTTG1 in MG63 cells after transfection with a miR- 300 plasmid. Double luciferase assay was used to detect the targeted binding of miR-300 and PTTG, Transwell invasion assay and CCK8 assay were used to detect the effects of overexpression of miR-300 and overexpression of PTTG1 plasmid on invasion and proliferation of osteosarcoma cell line MG63.
Objective:
PTTG1 was highly expressed in MG63 cells (P=0.0002). PTTG1 knockdown significantly inhibited the invasion (P=0.0002) and proliferation (P=0.0039) of MG63 cells. Based on the results of online prediction of complementary miRNAs to PTTG1 and analysis of the data from NCBI database, miR-300 was determined as the target miRNA in this study. qRT-PCR results showed a significantly decreased expression of miR-300 in MG63 cells (P=0.0004). Overexpression of MiR-300 in MG63 cells significantly decreased the expression of PTTG1 (P=0.0007), and the expressions of miR-300 and PTTG1 were negatively correlated. Dual luciferase assay showed that miR-300 could specifically bind to PTTG1 (P=0.001). Overexpression of PTTG1 could significantly reverse the effect of miR-300 overexpression on invasion (P=0.0003) and proliferation (P=0.0077) of MG63 cells.
Objective:
Overexpression of miR-300 can inhibit the invasion and metastasis of osteosarcoma cell MG63 by targeting PTTG1.
Insights
MicroRNA-300 (miR-300) inhibits osteosarcoma cell invasion and proliferation by targeting Pituitary Tumor Transforming 1 (PTTG1). This finding reveals a novel mechanism for controlling osteosarcoma metastasis.
Area of Science:
- Molecular Biology
- Oncology
- Biochemistry
Background:
- Osteosarcoma is a primary bone malignancy characterized by high invasion and metastasis rates.
- Understanding the molecular mechanisms driving osteosarcoma progression is crucial for developing effective therapies.
Purpose of the Study:
- To investigate the role of miR-300 and PTTG1 in osteosarcoma invasion and metastasis.
- To elucidate the molecular mechanism underlying osteosarcoma invasion and metastasis involving miR-300 and PTTG1.
Main Methods:
- Western blot and qRT-PCR were used to assess PTTG1 and miR-300 expression in osteosarcoma cells.
- Transwell invasion and CCK8 assays evaluated the effects of PTTG1 knockdown and miR-300 overexpression on cell invasion and proliferation.
- Online prediction, NCBI database analysis, and dual luciferase assays identified and confirmed the direct binding of miR-300 to PTTG1.
Main Results:
- PTTG1 was highly expressed in osteosarcoma cells, and its knockdown significantly inhibited invasion and proliferation.
- miR-300 expression was significantly decreased in osteosarcoma cells.
- Overexpression of miR-300 reduced PTTG1 expression and inhibited cell invasion and proliferation, with PTTG1 overexpression reversing these effects.
- miR-300 directly targets PTTG1.
Conclusions:
- miR-300 acts as a tumor suppressor in osteosarcoma by targeting PTTG1.
- Overexpression of miR-300 inhibits osteosarcoma cell invasion and metastasis through the downregulation of PTTG1.
- This study identifies a novel miR-300/PTTG1 regulatory pathway in osteosarcoma progression.
