Synthetic mRNA-based gene therapy for glioblastoma: TRAIL-mRNA synergistically enhances PTEN-mRNA-based therapy

Glioblastoma (GBM) is characterized as having high molecular heterogeneity and complexity, which can be well revealed by genomic study. A truly effective treatment for GBM should flexibly address its heterogeneities, complexity, and strong drug resistance. This study was performed to explore the effectiveness of an mRNA-based therapeutic strategy using in vitro synthesized PTEN-mRNA and TRAIL-mRNA in tumor cells derived from PTEN-deletion patients. The PTEN gene alterations were revealed by whole-exome sequencing of three paired clinical GBMs and selected as the therapy target. Patient-derived primary glioblastoma stem cells (GBM2) and a DBTRG-cell-derived xenograft were used to detect mRNA's cytotoxicity in vitro and tumor suppression in vivo. Following the successful in vitro synthesis of PTEN-mRNA and TRAIL-mRNA, the combinational treatment of PTEN-mRNA and TRAIL-mRNA significantly suppressed tumor growth compared with treatment with PBS (96.4%), PTEN-mRNA (89.7%), and TRAIL-mRNA (84.5%). The combinational application of PTEN-mRNA and TRAIL-mRNA showed synergistic inhibition of tumor growth, and the JNK pathway might be the major mechanism involved. This study provided a basis for an mRNA-based therapeutic strategy to be developed into an effective patient-tailored treatment for GBM.