ACTA1 and neoplasm: Consistent with the observed phenotypes, the loss of EZH2 expression in both orthotopic models neither reduced tumor cell proliferation (as determined by the immunohistochemical analysis of Ki67, Figure 1G and Figure S1A), nor did it render the composition of the PDAC stroma less aggressive, as illustrated by the determination of the activated stroma index (αSMA-positive fibroblasts/collagen) [42] (Figure 1G and Figure S1B,D).