Mesenchymal Stem Cell-based Cancer Gene Therapy: Application and Unresolved Problems

There are many barriers that have hindered the progress of clinical application of gene therapy as a potential method for treating cancer. These limitations are caused by transduction/delivery failure rates with viral vector systems and were due to the resultant non-specific targeting as well as the triggering of immune system stimulation. Recently, mesenchymal stem cells (MSCs) were found to be advantageous in improving tumor tropism as well as in providing an immune-privilege. Therefore, the combination of viral vector systems and stem cells was suggested as an attractive solution to promote targeted-delivery of anticancer therapeutics to tumor sites. In this regard, many published studies have shown that MSCs could be useful as a potential vehicle for delivering anticancer agents to tumors. In this review, the disadvantages of viral vector systems for gene therapy were analyzed, and an updated account on the role of MSCs in cancer gene therapy was presented. In addition, major safety and therapeutic unresolved problems facing this approach in clinical application were also addressed.