IGF1R and glioma: Supporting this notion, we found that repeated administration of tamoxifen (twice a month), which could further improve the recombination activity of NG2‐CreER, fully blocked glioma incidence in the IGF1R (flox/flox) mice (Figure 2J).We noted that the survival of these mice with repeated tamoxifen administration was only minimally further extended (Figure 2I).