Antiangiogenic variant of TSP-1 targets tumor cells in glioblastomas

Area of Science:

• Oncology
• Molecular Biology
• Biotechnology

Background:

• The thrombospondin-1 Three Type-1 Repeat (3TSR) domain exhibits anti-angiogenic properties.
• Its direct impact on glioblastoma (GBM) tumor cells remains largely unexplored.
• Targeting both tumor cells and tumor vasculature is crucial for effective cancer therapy.

Purpose of the Study:

• To investigate the potential of the 3TSR domain to target glioblastoma (GBM) cells.
• To evaluate the efficacy of engineered mesenchymal stem cells (MSCs) delivering 3TSR and secretable TRAIL (S-TRAIL) for combined tumor cell and endothelial cell targeting.
• To assess the therapeutic potential of this combined approach in preclinical GBM models.

Main Methods:

• In vitro studies assessing 3TSR's effect on death receptor (DR) 4/5 expression and apoptosis induction in GBM cells.
• Engineering of human mesenchymal stem cells (MSCs) to co-deliver 3TSR and S-TRAIL.
• In vivo evaluation of MSC-3TSR/S-TRAIL efficacy in murine GBM models, including tumor growth inhibition, targeting of tumor cells and vasculature, and survival analysis.

Main Results:

• 3TSR upregulates death receptor (DR) 4/5 expression in a CD36-dependent manner, sensitizing GBM cells to TRAIL-induced apoptosis.
• Engineered MSCs successfully delivered 3TSR and S-TRAIL, demonstrating synergistic anti-tumor effects.
• A single administration of MSC-3TSR/S-TRAIL significantly inhibited tumor progression, targeted both GBM cells and tumor vasculature, and extended survival in mice.

Conclusions:

• The 3TSR domain can prime resistant GBM cells for apoptosis via DR upregulation.
• MSC-mediated delivery of 3TSR and S-TRAIL offers a promising strategy for simultaneously targeting tumor cells and associated endothelial cells.
• This dual-targeting approach shows significant potential for treating a broad spectrum of cancers, including glioblastoma, and advancing 3TSR/TRAIL therapies into clinical practice.