Temozolomide resistance and tumor recurrence: Halting the Hedgehog

Area of Science:

• Neuro-oncology
• Cancer biology
• Molecular medicine

Background:

• Glioblastoma Multiforme (GBM) is a lethal brain tumor with poor outcomes due to therapeutic resistance.
• Temozolomide (TMZ), radiation, and surgery are standard GBM treatments, but resistance remains a major challenge.
• Understanding resistance mechanisms is critical for developing effective therapeutic strategies.

Purpose of the Study:

• To investigate the role of the Sonic Hedgehog (SHH) pathway in Temozolomide (TMZ) resistance in Glioblastoma Multiforme (GBM).
• To identify molecular targets and therapeutic interventions to overcome GBM therapy resistance.
• To explore the potential of RNA-based therapies delivered via stem cells for GBM treatment.

Main Methods:

• Analysis of Sonic Hedgehog (SHH) pathway activation in TMZ-resistant GBM cells.
• Investigating the role of miR-9 and its target PTCH1 in regulating SHH signaling.
• Utilizing Mesenchymal Stem Cells (MSCs) to deliver anti-miR-9 therapy to GBM cells via exosomes and gap junctions.

Main Results:

• SHH pathway activation, independent of ligand, contributes to TMZ resistance in GBM by upregulating the MDR1 gene.
• miR-9 is upregulated in chemoresistant CD133+ GBM cells and suppresses PTCH1, leading to SHH pathway activation.
• Delivery of anti-miR-9 via MSCs demonstrated potential in reversing TMZ resistance in GBM cells.

Conclusions:

• The SHH pathway is a key mediator of TMZ resistance in GBM, offering a potential therapeutic target.
• miR-9 plays a critical role in activating the SHH pathway in resistant GBM.
• Cell-based delivery of anti-miR-9 represents a promising strategy to overcome GBM chemoresistance.