Figure 3.

The efficacy of HB1.F3.CD neural stem cells (NSCs) as a cell carrier for CRAd-S-pk7 virus in a glioma stem cell–derived xenograft model. A) GBM43FL glioma cells were cultured and exposed to a total of 10 Gy radiotherapy (XRT) treatment (5 days × 2 Gy), temozolomide (50 uM), or cocultured with HB1.F3.CD-GFP⁺ cells loaded with CRAd-S-pk7 (50 IU per cell). After 72 hours of incubation, cells were collected and stained for glioma stem cell (GSC) markers CD133 and CD15 and subjected to fluoresecent-activated cell sorting (FACS) analysis. Representative FACS plots show the percentage of CD15⁺, CD133⁺, or CD15⁺CD133⁺ GBM43FL cells. B) The percentage of positive populations of GSCs in the three treatment groups. All three populations of GSCs were statistically significantly reduced in oncolytic adenoviral virotherapy (OV)–loaded NSC treatment group compared with the XRT or chemotherapy (TMZ) treatment groups (P < .001), compared using Student t test. Bars represent means from three independent experiments; error bars refer to 95% confidence intervals. C) The OV-loaded HB1.F3.CD therapy was tested in vivo. GBM43FL cells were FACS sorted, and 5×10³ CD133⁺ cells were intracranially implanted in the brains of nude mice (n = 7 per group). Three days after tumor implantation, mice were treated either with phosphate-buffered saline (PBS), 5×10⁵ HB1.F3.CD cells, 5×10⁵ HB1.F3.CD cells loaded with 50 IU per cell of CRAd-S-pk7, or 2.5×10⁷ IU of CRAd-S-pk7 intratumorally. P ¹ represents P value 1 in this table where PBS treated group served as reference and P ² represents P value 2 where CRAd-S-pk7+HB1.F3.CD serve as reference. Survival curves were obtained by the Kaplan–Meier method, and overall survival time was compared between groups using the log-rank test. All statistical tests were two-sided. ***P < .001; **P < .01; *P < .05.