Fig. 1. Western blot of B7-H4. Each tissue lane represents 50 μg total protein. RL95.2 is an endometrial cell line positive for B7-H4 (15 μg protein). Chemiluminescence, film exposure 1 min.

Fig. 2. Immunohistochemical localization of B7-H4 in benign, hyperplasia and cancer of the endometrium. (A) Proliferative endometrium; (B) secretory endometrium; (C) atrophic endometrium; (D) hyperplasia; (E) atypical hyperplasia; (F) carcinoma.

Fig. 3. B7-H4 staining patterns and clinicopathologic variables in endometrial cancers. (A) Staining pattern of B7-H4, either apical membranous staining (pattern 1) or circumferential membranous and cytoplasmic staining (pattern 2), grade 3 tumors is statistically different from grade 1 tumors, p = 0.018; (B) proportion of B7-H4 positive cells, the high risk tumor group is statistically different from the low risk tumor group, p = 0.001; (C) B7-H4 staining intensity, the high risk tumor group is statistically different from the low risk tumor group, p = 0.032. An * indicates a statistical difference between groups according to Fisher's exact test.

Fig. 4. Immunohistochemical localization of B7-H4, CD3, CD8 and activated caspase-3 in endometrioid adenocarcinoma. (A) B7-H4, cytoplasmic and membranous staining in tumor cells; (B) CD3-positive T cells at tumor–stromal interface (TALs) and infiltrating tumor (TILs); (C) CD8-positive T cells at tumor–stromal interface (TALs) and infiltrating tumor (TILs); (D) activated caspase-3 in tumor cells.

Fig. 5. CD3 or CD8-positive T cells at tumor–stromal interface (TALs): correlation with proportion of B7-H4 positive cells, staining intensity and pattern. *, p = 0.04 by Wilcoxon Rank-Sum test; **, p = 0.015 by Wilcoxon Rank-Sum test; †, predominantly apical membranous staining; ‡, predominantly circumferential membranous and cytoplasmic staining.

Fig. 6. CD3 or CD8-positive T cells infiltrating tumor (TILs): correlation with proportion of B7-H4 positive cells, staining intensity and pattern. *, p = 0.039 by Wilcoxon Rank-Sum test; **, p = 0.031 by Wilcoxon Rank-Sum test; †, predominantly apical membranous staining; ‡, predominantly circumferential membranous and cytoplasmic staining.

Fig. 7. Immunohistochemical localization of CD14 positive macrophages and B7-H4 in endometrioid adenocarcinoma (A). CD14 positive macrophages are observed at the tumor stromal interface (open arrows) and in malignant glandular luminal spaces (solid arrows). Tumor epithelial cells are negative for CD14; (B) B7-H4 is highly expressed in tumor cells but only faintly detected in luminal macrophages (solid arrows). Stromal macrophages are negative for B7-H4 (open arrows).

B7-H4 staining pattern by histologic diagnosis

Proportion of B7-H4 positive cells by histologic diagnosis

Staining intensity of B7-H4 according to histologic diagnosis