Fig. 2
From: Current status and potential challenges of mesenchymal stem cell-based therapy for malignant gliomas
The pattern of mesenchymal stem cell (MSC)-based therapy studies for glioma. By means of tumour-specific tropism of MSCs, BMSCs, AT-MSCs, or UC-MSCs can be transduced to deliver anticancer agents such as TRAIL, interferon (IFN-β and IFN-γ) and interleukins (IL-2, IL-7, IL-18, and IL-12) directly to glioma sites to kill tumour cells or to regulate immune responses. MSCs can also be engineered with enzymes to convert pro-drugs into active drugs at the glioma site. For example, MSCs engineered to express yeast cytosine deaminase (CD), herpes simplex virus thymidine kinase (HSV-TK), and rabbit carboxylesterase (rCE) can convert systemically administered anti-tumour pro-drugs (5-fluorocytosine (5-FC), ganciclovir, and CPT-11, respectively) to their active form at the glioma site and thereby inhibit glioma growth while limiting peripheral toxicity. In addition, MSCs loaded with oncolytic adenovirus CRADs and Delta-24-RGD have been shown to have activity against glioma. 5-FU 5-fluorouracil, ECM extra-cellular membrane, SN-38 7-ethyl-10-hydroxycamptothecin, TP triphosphate