Table 3.
Expression of mTOR, rpS6 and Its Phosphorylated Forms, and RAPTOR in Gliomas.
| Reference | Cohort | Protein evaluated | Survival | Difference with our study |
|---|---|---|---|---|
| Korkolopoulou et al.17 | 25 DA, 12 AA, 71 GBM | Manual HSCORE system. pmTOR HSCORE increases with grade. Mann–Whitney analysis. | pmTOR correlated with disease-free survival. Analysis grouped grades II, III, and IV in the same analysis. | In our study, statistical analyses were based on ANOVA and survival was performed in GBMs as a single group. |
| Li et al.18 | 27 PA + DA, 24 AA, 36 GBM | Manual HSCORE system. pmTOR increases with grade. Grouped grades I and II, no indication of statistical test. | In our study, statistical analyses were based on ANOVA and different grades were not grouped together for analysis. | |
| Pelloski et al.21 | 268 GBM + 60 GBM for validation | Manually classified pmTOR positive or negative | pmTOR was associated to worse survival in GBM in univariate analysis. | Cutoff points for the survival |
| Thorarinsdottir et al.23 | 42 PA, 21 DA, 13 AA, 9 GBM pediatric | Manual HSCORE. pmTOR expression increases with grade. | No relationship with survival | Age of the cohort. Thorarinsdottir et al. included patients below 21 years of age. |
| Annovazzi et al.12 | 34 GBM, 10 AA, 10 DA, and 10 OL | Manual three-tier scale. pmTOR and p(240–244)S6 increase with grade. No indication of statistical test used. Nuclear staining of pmTOR. | No correlation with survival in GBMs. There is no indication of the cutoff values used for the survival analysis. | In our study, automated immunohistochemistry analysis and continuous HSCORE classification were used to calculate cutoff point for the survival analysis. |
| Hütt-Cabezas et al.15 | 177 PA | Four-tier scale. Moderate/strong mTOR positivity in 47% of cases, 59% for p(235–236)S6, and 63% for RAPTOR. | No relationship with survival | Composition of the cohort. Hütt-Cabezas et al included PAs only. |
| Rodriguez et al.32 | 43 PA, 24 aggressive PA, 25 histologically anaplastic PA | Four-tier manual score. p(235–236)S6 score increases in aggressive PAs. | Composition of the cohort. Rodriguez et al. included PAs only. | |
| Jentoft et al.16 | 16 PA, 6 LGSI, 1 DA, 1 GG, 39 sporadic PA | Four-tier manual score. p(235–236)S6 positivity in 33% sporadic PA. | Composition of the cohort. Jentoft et al. included PAs only. | |
| Mueller et al.20 | Pediatric 25 PA, 7 DA, 7 AA, and 9 GBM | Four-tier manual score. p(235–236)S6 and p(240–244)S6 increase with grade. | No pS6 relationship with survival | Age of the cohort. Mueller et al. included patients below 18 years of age. |
| Yang et al.33 | 16 DA, 35 AA, 45 GBM | Manually classified in low or high. p(235–236)S6 increases with grade. | pS6 expression was associated with a worse prognosis in univariate and multivariate analysis | In our study, automated HSCORE was used to calculate cutoff. In Yang et al, criteria for classification were based on renal cell carcinoma literature. |
| McBride et al.19 | 22 DA, 16 OL e 7 mixed | Four-tier manual score. p(235–236)S6 and p(240–244)S6 present in 76% of cases. | Statistically significant inverse relationship between OS and p 235/236 and pSer-240. | Composition of the cohort. McBride et al. included grade II astrocytomas only. |
Abbreviations: DA, diffuse astrocytoma; AA, anaplastic astrocytoma; GBM, glioblastoma; PA, pilocytic astrocytoma; OL, oligodendroglioma; GG, ganglioglioma; LGSI, low grade astrocytoma subtype indeterminate; OS, overall survival.