Table 1.
The expression of PD-L1 in human glioma tissues.
| Materials | PD-L1 antibody | Criteria for IHC positive | Expression rate of PD-L1 | Other results | Reference |
|---|---|---|---|---|---|
| TMA:1035 GBM specimens (grade IV tumors with gliosarcoma were not included) |
SP142 | <5% or <2+ or ≥2+ and ≥5% | PD-L1 positive in 19% of all specimens | Xiu et al., 2016 | |
| 233 GBM specimens; WHO I/II, 15.6%; WHO III 13.6%; gliosarcomas 3.7% | SP142 | PD-L1 expression detected on cell membranes | PD-L1 positive in 6.1% (21/345) of all glioma specimens, and in 35.0% (57/163) of all GBM specimens | High expression of PD-L1 in WHO IV GBM specimens, while low expression in IDH-mutant glioma specimens | Garber et al., 2016 |
| 327 glioma specimens (grade I-IV); 198 GBM specimens | SP142 | PD-L1 expression detected on cell membranes | PD-L1 positive in 8.1% (24/295) of all glioma specimens, and in 10.1%(19/189) of all GBM specimens | Low expression of PD-L1 in IDH-mutant glioma specimens | Hodges et al., 2017 |
| 117 newly diagnose glioblastoma specimens, 18 recurrent glioblastoma specimens | Clone 5H1 | Membranous PD-L1 expression: PD-L1 detected on >5% of the tumor cell membranes; | PD-L1 positive in 37.6% (44/117) of newly diagnosed glioblastoma specimens and 16.7%(3/18) of recurrent glioblastoma specimens; | Berghoff et al., 2015 | |
| Diffuse/fibrillary PD-L1 expression: PD-L1 detected in non-necrotic areas | PD-L1 expression in 84.6% (99/117) of newly diagnosed glioblastoma specimens and 72.2% (13/18) of recurrent glioblastoma specimens. | ||||
| 43 WHO II/III (39 IDH-mutant, 4 IDH-wild type) glioma specimens; 14 GBM with IDH-mutant specimen; 117 GBM with IDH-wild type specimens | Clone 5H1 | Membranous PD-L1 expression: PD-L1 detected on >1% of the tumor cell membranes; | Positive expression in 56.2% (68/121) of IDH-wild type glioma and 5.7% (3/53) of IDH-mutant glioma; | A significant negative correlation between PD-L1 expression and IDH-mutant status (P < 0.001) | Berghoff et al., 2017 |
| Diffuse/fibrillary PD-L1 expression: PD-L1 detected in >25% of all non-necrotic areas | Positive expression in 84.3% (102/121) of IDH-wild type glioma and 37.3%(20/53) of IDH-mutant glioma. | ||||
| 9 GBM specimens; 1 mixed glioma (WHO III) specimen | Clone 5H1 | PD-L1 expression was divided into 4 levels: <25%; 25–50%; 50–75% and >75% | PD-L1 expression in all 10 specimens (with a positive rate of 50~90%) | Wintterle et al., 2003 | |
| TMA: 99 GBM specimens | EPR1161 | Compact brown particles shown on cell membranes | 60.6% of the specimens with >1% PD-L1 expression; 38.3% of the specimens with >5% PD-L1 expression | Nduom et al., 2016 | |
| TMA: 229 glioma specimens (WHO I~IV) | Rabbit polyclonal antibody anti-PD-L1 | >5% of tumor cell with membrane or cytoplasm PD-L1 expression | 49.2, 53.7, and 68.6% of grade II, III and IV gliomas with positive PD-L1 expression respectively | No significant correlation between PD-L1 expression and WHO levels (P = 0.327) | Zeng et al., 2016 |
| 54 brain tumor specimens, 1 epilepsy specimen | clone MIH1 eBioscience | Positive signals detected in glioma cells | Positive expression of PD-L1 in 85.2%(46/54) of all brain tumor specimens and 19/19 GBM specimens | The positive expression rate of PD-L1 in GBM specimens higher than that in other brain tumor specimens | Wilmotte et al., 2005 |
| 64 glioma specimens (grade I-IV) | ab58810, Abcam | Positive signals detected in>5% of all tumor cells (membrane or cytoplasm) | PD-L1 positive in 78.12% (50/64) of all specimens, 60.87% (14/23) of the LGG specimens and 87.80%(36/41) of the HGG specimens | A significant positive correlation between PD-L1 expression and WHO levels (P = 0.013) | Xue et al., 2017a |
| Initial and secondary resected tumor specimens from 16 GBM patients (excision time within 2 years after the first operation) | 28–8, Abcam | PD-L1 in tumor cells was graded as “–” (absence of staining), “+” (up to 25% of cells stained), “++” (25–50% of cells stained) or “+++” (more than 50% of cells stained) | Initial resected tumor specimens median:++; secondary resected tumor specimens median:+++ | No difference between the expression of PD-L1 in initial and secondary resected tumor (P = 0.187) | Miyazaki et al., 2017 |
| TMA: 54 GBM specimens | Cell Marque, Rocklin, CA, USA | PD-L1 expression detected in >5% of all tumor cell membranes | PD-L1positive in 31.5% of all GBM specimens | Han et al., 2017 | |
| Initial and secondary resected tumor specimens from 64 GBM | E1LRN, Cell Signaling |
Diffuse/fibrillary PD-L1 expression in 75% of all specimens; Cytoplasmic PD-L1 expression in 20% of all specimens; membranous PD-L1expression in 5% of all specimens | PD-L1 expression level in secondary resected GBM specimens reduced 66.71% compared to that in initial resected GBM specimens (p = 0.0045) | Heynckes et al., 2017 | |
| 62 malignant brainstem glioma specimens | ab205921, Abcam, Cambridge, UK |
Unknown | PD-L1 expression in 59.7% (37/62) of all specimens | Zhang et al., 2017 | |
| TMA: 115 GBM specimens | E1L3N, Cell Signaling |
Positive signals detected in >5% of tumor cells (either membrane or cytoplasm) | PD-L1 positive in 32.2% (37/115) of all GBM specimens | PD-L1 expression was significantly associated with IDH-mutant status (P = 0.008) | Lee et al., 2018 |
TMA,tissue microarray; GBM, glioblastoma multiforme; IDH-mutant, isocitrate dehydrogenase-mutant.