Moreover, we also found an overall inactivation of multiple mediators of the MAPK pathway (i.e., JNK, MEK, MMK3, MMK6, TP53, RPS6KA1, RPS6KA3, ERK1/2, MSK2, and MAPK14) in sst5TMD4-overexpressed GBM cells, which might be also associated with the oncogenic actions of this splicing variant in GBM cells since MAPK inactivation (including the well-known tumor suppressor TP53) has been linked to an inhibition of apoptosis in order to enhance cell survival [50,51,52,53]. Here, RPS6KA1 is linked to glioblastoma.