SSTR1 and central nervous system cancer: Although SSTR 2 is the predominant subtype expressed in these brain malignancies, Lamszus et al. reported the expression of SSTR1 and SSTR3 mRNA levels in 7–9 cell lines derived from human gliomas, as well as in a few cases of glioblastomas; however, SSTR4 and SSTR5 mRNA levels were rarely seen [132].