Table 1.
Studies on the Correlations between Tumour HLA-G Expression and Clinicopathological Factors and Clinical Outcome of Breast Carcinoma Patients.
| First Author [Ref.] | mAb and Included Patient Cohort | HLA-G Quantification Method | HLA-G+ Samples (%) | Association with Tumour HLA-G Expression | |
|---|---|---|---|---|---|
| Clinico-Pathological Parameters with p-Values ≤ 0.05 | Clinical Outcome (p-Value) | ||||
| * Engels [21] | 4H84 Post-meno-pausa, hormone receptor positive BC patients |
Tumour was considered HLA-G-positive when >1% of tumour cells were stained Tumour immune-susceptibility was expressed in IS and was generated by adding up regression coefficients of HLA-G, HLA-class I, HLA-E and FoxP3 expression, thereby creating three groups; low, intermediate and high IS |
Low IS: 817/1636 (50) Intermediate IS: 318/1636 (19) High IS: 501/1636 (31) Total cohort: 484/2042 (24) |
Increased tumour grade. | Cox univariate analysis: OS (ns); RFP (ns); CSS (ns). Cox proportional hazard analysis, intermediate vs. high IS: OS, HR = 1.471 (none provided); RFP, HR = 1.539 (none provided); CSS, HR = 2.119 (none provided). Cox proportional hazard analysis, low vs. high IS: Shorter OS, HR = 1.602 (0.002); Shorter RFP, HR = 1.634 (0.002); Shorter CSS, HR = 2.103 (<0.001). |
| * De Kruijf [20] | 4H84 Early BC patients |
Tumour was considered HLA-G-positive when >1% of tumour cells were stained | 201/501 (40) | HLA-class I expression; Her2 over-expression; Type of received systemic therapy. |
KM analysis: OS (ns); RFP (ns). KM analysis, stratified for HLA-class I expression, n = 361: OS (ns); RFP (ns). KM analysis, stratified for loss of HLA-class I expression, n = 106: OS (ns); Shorter RFP (0.035). |
| Ishibashi [17] | 4H84 BC patients, random cohort |
Low (absent (-) or weak (+)) staining vs. high staining (moderate (++) or strong (+++)) | +: 58/102 (57) ++: 32/102 (31) +++: 6/102 (6) High staining: 38/102 (37) |
Tumour ER down-regulation; Tumour PR down-regulation. |
KM analysis: Shorter OS (0.006); Shorter DFS (0.049). |
| Ramos [18] | MEM-G/2 Patients with invasive ductal BC |
Based on ROC-curve analysis | 28/45 (62) | Increased LNM | KM analysis: Shorter OS (0.03) Cox multivariate analysis: Shorter OS, HR = 8.8 (0.04) |
| He [19] | HGY BC patients, random cohort |
Absent (0%) and weak (1–25%) staining vs. moderate (25–50%) and strong (>50%) staining | Cohort with available follow-up Weak staining: 42/84 (50) Moderate/ strong staining: 25/84 (30) |
Increased tumour size; Increased LNM; Advanced disease stage; Tumour ER over-expression; Tumour PR over-expression. |
KM analysis: Shorter OS (0.028) Cox multivariate analysis: Shorter OS, HR = 10.2 (0.006) |
The technique used in all mentioned studies for HLA-G detection was immunohistochemistry with formalin-fixed paraffin-embedded tissue. p-Values ≤ 0.05 were considered statistically significant. Abbreviations: BC, Breast Carcinoma; CSS, Cancer-Specific Survival; DFS, Disease-Free Survival; ER, Estrogen Receptor; HR, Hazard Ratio; IS, Immune Score; KM, Kaplan–Meier; LNM, Lymph Node Metastasis; ns, not significant; OS, Overall Survival; PR, Progesterone Receptor; RFP, Recurrence-Free Period. * Tissue microarrays were used to determine the percentage of HLA-G expression in the tumour samples.