COL1A2 and sarcoma: To label the remaining cells, which we reasoned were either sarcoma cells or fibroblasts based on expression of mesenchymal markers such as COL1A1, COL1A2, CALD1, CALU, and negativity for other TME markers, we scored the cells for average expression of the top 30 genes that were upregulated in mouse CAFs compared to sarcoma cells (Fig. 2b).