Figure 1.

Single species cluster dendrograms define canine and human osteosarcoma as distinct from normal organs and osteosarcoma cell lines. Cancer defining gene signatures were generated by calculating the differential expression between canine and human osteosarcoma samples and their respective normal organs using limma (Linear Models for Microarray Data, adjusted p value < 0.01). A. The canine cancer signature consists of 3471 genes and B. human cancer signature 2705. High level, unsupervised hierarchical clustering conducted in each species separately resulted in osteosarcoma samples clustering together and distinctly from normal tissues and their respective cancer cell lines.