IGF1 and glioblastoma: IGF1 promotes PI3K/AKT signaling, and therefore cell survival and proliferation.22 To examine how increased IGF1 might influence the establishment of senescence, anti‐IGF1 antibody or recombinant IGF1 was added with matrine to GBM cells, and cells were collected to prepare protein lysates for Western blot analysis 3 days later.