SSTR5 and glioblastoma: Therefore, based on all these data, it is tempting to speculate that a potential functional association between SSTR2, SSTR5 and sst5TMD4 could also exist in GBM, and that the high sst5TMD4 expression levels found in tissues/cells from GBM patients could help, in part, to explain the inefficacy of SSA therapy in the scarce and limited GBM trials implemented hitherto [29,39,54,55,56].