Suicide gene therapy has a long history, and its effectiveness is now under investigation. The bystander death effect therapeutic strategy proved successful in treating malignant glioma; nevertheless, non-replicating viral vectors may not be able to cover a large invading region of glioma cells. Tumor-trophic stem cell migration and viral replication capacities have the potential to overcome the refractory mechanisms of malignant glioma. Surprisingly, the time to response (partial or total response) was delayed for more than 6 months after the initial Toca 511 treatment, reflecting a stronger antitumor immune response. Immunosuppressive cells such myeloid-derived suppressor cells and tumor-associated macrophages were found to be lower in human glioblastoma tissues after treatment. These mechanisms may have a long-term impact on people with malignant glioma. NSCs and MSCs, for example, might be employed to cover glioma cells' more broad invading areas. However, we must investigate which brain stem cells are the most suited. More study is needed to confirm the migratory potential and survival ratio of the implanted stem cells in the brain utilizing comparative analysis. Suicide gene therapy using stem cell migratory capability and/or viral replicating capability for malignant glioma may recapture the spotlight.
Exploiting tumor-intrinsic signals to induce mesenchymal stem cell-mediated suicide gene therapy to fight malignant glioma
