FIGURE 3 from Hemangiosarcoma Cells Promote Conserved Host-derived Hematopoietic Expansion

Immune cell infiltration and comparative immune signatures between canine hemangiosarcoma and human angiosarcoma. A, A total of 461 upregulated genes were identified in immune-high (N = 8) compared with immune-low (N = 5) groups in human angiosarcomas (FDR P value < 0.05). B, 567 immune gene signatures were identified among three molecular subtypes of canine hemangiosarcomas (N = 76; FDR P value < 0.001; fold change > 3). The heat maps show upregulated (red) and downregulated (green) genes by unsupervised hierarchical clustering (average linkage; mean-centered; log₂ transformed). C, Venn diagram shows 58 common genes associated with signaling pathways of immune cell functions between human and canine tumors. Representative photomicrographs of H&E and IHC staining showing histologic morphology and immune cell infiltration in canine hemangiosarcoma (D) and human angiosarcoma tissues (E) using anti-CD3, anti-PAX5, anti-MAC387, and anti-Iba1 (for canine) or anti-CD163 (for human) antibodies for detecting T cell, B cell, and macrophages. Horseradish peroxidase (counterstain = hematoxylin) or alkaline phosphate (for Iba1; counterstain = methylene blue). Bar = 50 µm. Scatter plots display correlation between transcriptional and IHC immune score in canine hemangiosarcoma (F) and human angiosarcoma (G). Spearman correlation coefficient (R) was calculated.