The Clinical and Prognostic Significance of Activated AKT-mTOR Pathway in Human Astrocytomas

Table 4

Summary of reports investigating the role of phosphorylated 4E-BP1 in astrocytomas.

Report (number of cases and grades)	Antibody used	Immunostaining percentage	Correlations with clinicopathological features	Other correlations	Survival analysis
Korkolopoulou et al. [30] (111 patients: 25 grade II, 15 III, and 71 IV)	Rabbit polyclonal anti-p-4E-BP1/2/3 (Ser36) ab (SCB), diluted 1 : 50 for IHC and 1 : 200 for WB	82.4% (61/74) nuclear	p-4E-BP1 with tumor grade	p-4E-BP1 with; (i) nuclear p-AKT; (ii) cytoplasmic p-ERK; (iii) p-mTOR; (iv) VEGF	(i) p-4E-BP1 adversely affected survival in the entire cohort and marginally in glioblastomas; (ii) Multivariate analysis: p-4E-BP1 as an independent predictor of survival in the entire cohort as well as in glioblastomas
Ermoian et al. [36] (71 patients: 28 grade II, 17 III, and 26 IV	Anti-p-4E-BP1 ab (CST) (WB)	Not provided	p-4E-BP1 unrelated to tumor grade	p-4E-BP1 with p-AKT	No significant correlation
Riemenschneider et al. [23] (29 grade IV)	Rabbit polyclonal anti-p-4E-BP1 (Ser65) ab (CST), diluted 1 : 50 (IHC)	Not provided	—	No significant correlation	—

ab: antibody, CST: Cell Signaling Technology (Beverly, MA), IHC: immunohistochemistry, p-ERK: phosphorylated extracellular-signal-regulated kinase, SCB: Santa Cruz Biotechnology, VEGF: vascular endothelial growth factor, WB: Western blot.