Immunohistochemical staining for the mesenchymal-marker gene COL1A1 in our SJNBL063820 PDX sample (#1, left) and in two other PDX samples SJNBL046145 (#2, middle) and SJNBL047443 (#3, right). The upper panel shows a UMAP plot colored by the expression of COL1A1 in our PDX cohort, with the numbers indicating the UMAP clusters corresponding to the 3 stained PDX samples
