In this sense, Sunayama et al. [30] have shown that inhibition of the PI3K/mTOR and the MEK/ERK pathways in glioblastoma stem-like cells induces an increase in the activity of the other pathways and that this cross-regulation disappeared when RPS6KB1 expression was inhibited by siRNAs. The gene discussed is MAPK1; the disease is glioblastoma.