Tumor necrosis factor-related apoptosis-inducing ligand induces cytotoxicity specific to osteosarcoma by microRNA...

Area of Science:

• Oncology
• Molecular Biology
• Gene Therapy

Background:

• Osteosarcoma is an aggressive bone cancer with limited treatment options.
• Current TRAIL gene therapy lacks tumor selectivity, affecting normal cells.
• MicroRNAs (miRNAs) like miR-34 and miR-122 are tumor suppressors and can be engineered for targeted therapy.

Purpose of the Study:

• To develop a tumor-selective TRAIL gene therapy for osteosarcoma using miRNA response elements (MREs).
• To investigate the potential of miR-34 and miR-122 MREs for regulating TRAIL expression in osteosarcoma cells.
• To evaluate the efficacy and safety of the engineered adenoviral vector in preclinical models.

Main Methods:

• Utilized MREs of miR-34 and miR-122 in adenoviral vectors to control TRAIL expression.
• Assessed selective gene expression using luciferase assays in osteosarcoma and normal cells.
• Quantified TRAIL expression, apoptosis, and cytotoxicity via RT-qPCR, immunoblotting, and ELISA.
• Evaluated therapeutic efficacy and liver toxicity in osteosarcoma xenograft mouse models.

Main Results:

• miR-34 and miR-122 were found to be underexpressed in osteosarcoma tissues.
• MREs of miR-34 and miR-122 conferred selective gene expression in osteosarcoma cells.
• Adenovirus carrying TRAIL regulated by miR-34/122 MREs (Ad-TRAIL-34-122) selectively expressed TRAIL in osteosarcoma cells.
• Ad-TRAIL-34-122 induced apoptosis and cytotoxicity in osteosarcoma cells but not normal cells.
• In vivo studies showed Ad-TRAIL-34-122 reduced tumor growth without causing liver toxicity.

Conclusions:

• A novel miRNA-regulated biological cancer therapy targeting osteosarcoma was developed.
• The engineered adenoviral vector demonstrates significant tumor selectivity and therapeutic potential.
• This approach offers a promising strategy for future clinical application in osteosarcoma treatment.