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MiR-205 functions as a tumor suppressor via targeting TGF-α in osteosarcoma
Guojin Yang1, Peng Zhang2, Aibin Lv3
1Department of Orthopedics, the Second People's Hospital of Taizhou City, Jiangsu Province, China.
Abstract:
Osteosarcoma (OS) is the most common primary bone cancer, and it is most prevalent in children and young adults. The prognosis of OS remains poor, and survival of OS reached a plateau. The discovery of microRNAs (miRNAs) provides a new possibility for the early diagnosis and treatment of OS. In this study, we detected the expression level of miR-205 and Transforming growth factor-alpha (TGF-α) in 15 cases of clinical OS tissues and adjacent normal bone tissues. We found that the expression of miR-205 was significantly lower in OS tissues than in normal bone tissues; the expression of TGF-α mRNA was significantly increased in OS tissues than in normal bone tissues, the miR-205 was negatively correlated with TGF-α levels in both OS and normal bone tissues. Functional studies demonstrated that miR-205 significantly decreased the capability of cell proliferation, invasion and migration and induced G0/G1 growth arrest and apoptosis in OS cells. By using bioinformatics analytic tool (Targetscan), the 3'UTR of TGF-α gene was found to be a target of miR-205. Luciferase report assay further confirmed that TGF-α 3'UTR is a direct target of miR-205. We also found that the expression of TGF-α mRNA and protein was significantly down-regulated or up-regulated after miR-205 mimic or miR-205 inhibitor transfection. TGF-α knockdown study further showed that miR-205 regulated cell proliferation, invasion and migration by targeting TGF-α in OS. Enforced expression of TGF-α sufficiently restore the effects of miR-205 on cell proliferation, invasion and migration. In conclusion, our study suggested that miR-205 may function as a tumor suppressor via targeting TGF-α in OS, and the abnormal expression of miR-205 might be a key factor in OS progression.
Insights
MicroRNA-205 (miR-205) acts as a tumor suppressor in osteosarcoma (OS) by inhibiting TGF-α. Lower miR-205 levels correlate with increased TGF-α, promoting OS progression and poor prognosis.
Area of Science:
- Oncology
- Molecular Biology
- Genetics
Background:
- Osteosarcoma (OS) is a prevalent bone cancer with a poor prognosis, particularly in pediatric and young adult populations.
- MicroRNAs (miRNAs) offer potential for early diagnosis and novel therapeutic strategies in OS.
- Understanding the molecular mechanisms underlying OS progression is crucial for improving patient outcomes.
Purpose of the Study:
- To investigate the role of miR-205 and Transforming growth factor-alpha (TGF-α) in osteosarcoma.
- To determine the relationship between miR-205 expression and TGF-α levels in OS tissues.
- To elucidate the functional impact of miR-205 on OS cell behavior and its therapeutic potential.
Main Methods:
- Expression analysis of miR-205 and TGF-α mRNA in 15 OS tissues and adjacent normal tissues.
- In vitro functional assays to assess the effects of miR-205 on OS cell proliferation, invasion, migration, apoptosis, and cell cycle.
- Bioinformatic analysis (TargetScan) and luciferase reporter assays to validate TGF-α as a direct target of miR-205.
- miR-205 mimic/inhibitor transfections and TGF-α knockdown/overexpression studies to confirm the regulatory pathway.
Main Results:
- miR-205 expression was significantly downregulated, while TGF-α mRNA was upregulated in OS tissues compared to normal tissues.
- miR-205 negatively correlated with TGF-α levels and suppressed OS cell proliferation, invasion, and migration while inducing apoptosis and G0/G1 cell cycle arrest.
- TGF-α was identified as a direct target of miR-205, with miR-205 modulating TGF-α expression and downstream signaling.
- Restoration of TGF-α expression reversed the inhibitory effects of miR-205 on OS cell behaviors.
Conclusions:
- miR-205 functions as a tumor suppressor in osteosarcoma by directly targeting and downregulating TGF-α.
- The aberrant expression of miR-205 is implicated in osteosarcoma progression and may serve as a potential diagnostic biomarker or therapeutic target.
- Targeting the miR-205/TGF-α axis presents a promising strategy for novel osteosarcoma treatments.
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