MMP9 and neoplasm: Fibroblasts isolated from tumour and NCL samples display transcriptional differences ex vivo, demonstrated in Fig. 4a, c, where several genes such as TGF-β1, a key regulator of fibroblast activation, and MMP9 are upregulated in the CAFs compared to NCL fibroblasts (comparison within tissue types shown in Supplementary Fig. S3).