The application of mRNA-based gene transfer in mesenchymal stem cell-mediated cytotoxicity of glioma cells

// Xing-Rong Guo 1, * , Zhuo-Shun Yang 2, * , Xiang-Jun Tang 2, * , Dan-Dan Zou 2 , Hui Gui 2 , Xiao-Li Wang 1 , Shi-Nan Ma 1 , Ya-Hong Yuan 1 , Juan Fang 3 , Bin Wang 2, 4 , Li Zhang 2 , Xu-Yong Sun 5 , Garth L. Warnock 6 , Long-Jun Dai 2, 6 , Han-Jun Tu 1 1 Hubei Key Laboratory of Stem Cell Research, Taihe Hospital, Hubei University of Medicine, Shiyan, China 2 Department of Neurosurgery, Taihe Hospital, Hubei University of Medicine, Shiyan, China 3 Department of Animal Care Center, Hubei University of Medicine, Shiyan, China 4 The Biomedical Research Center, University of British Columbia, Vancouver, Canada 5 Guangxi Key Laboratory for Transplantation Medicine, 303 Hospital of PLA, Nanning, China 6 Department of Surgery, University of British Columbia, Vancouver, Canada * These authors have contributed equally to this work Correspondence to: Han-Jun Tu, email: sythj@sina.com Li Zhang, email: zhanglith@163.com Long-Jun Dai, email: ljdai@mail.ubc.ca , longjundai@gmail.com Keywords: glioblastoma, cancer therapy, mesenchymal stem cells, TRAIL, PTEN Received: October 14, 2015      Accepted: July 14, 2016      Published: July 25, 2016 ABSTRACT Since the tumor-oriented homing capacity of mesenchymal stem cells (MSCs) was discovered, MSCs have attracted great interest in the research field of cancer therapy mainly focused on their use as carries for anticancer agents. Differing from DNA-based vectors, the use of mRNA-based antituor gene delivery benefits from readily transfection and mutagenesis-free. However, it is essential to verify if mRNA transfection interferes with MSCs’ tropism and their antitumor properties. TRAIL - and PTEN -mRNAs were synthesized and studied in an in vitro model of MSC-mediated indirect co-culture with DBTRG human glioma cells. The expression of TRAIL and PTEN in transfected MSCs was verified by immunoblotting analysis, and the migration ability of MSCs after anticancer gene transfection was demonstrated using transwell co-cultures. The viability of DBTRG cells was determined with bioluminescence, live/dead staining and real time cell analyzer. An in vivo model of DBTRG cell-derived xenografted tumors was used to verify the antitumor effects of TRAIL - and PTEN -engineered MSCs. With regard to the effect of mRNA transfection on MSCs’ migration toward glioma cells, an enhanced migration rate was observed with MSCs transfected with all tested mRNAs compared to non-transfected MSCs ( p <0.05). TRAIL - and PTEN -mRNA-induced cytotoxicity of DBTRG glioma cells was proportionally correlated with the ratio of conditioned medium from transfected MSCs. A synergistic action of TRAIL and PTEN was demonstrated in the current co-culture model. The immunoblotting analysis revealed the apoptotic nature of the cells death in the present study. The growth of the xenografted tumors was significantly inhibited by the application of MSC PTEN or MSC TRAIL/PTEN on day 14 and MSC TRAIL on day 28 ( p <0.05). The results suggested that anticancer gene-bearing mRNAs synthesized in vitro are capable of being applied for MSC-mediated anticancer modality. This study provides an experimental base for further clinical anticancer studies using synthesized mRNAs.