TP53 and neoplasm: Immunohistochemical analysis of the cancer stem cell marker PROX1 revealed a significant decrease in PROX1 expression in invasive p53;fl/flSrsf1fl/+ tumour epithelial cells (Fig. 6d, e) corroborating our RNAseq results in short-term Cre-lox recombined Apc;fl/flSrsf1fl/+ tissue (Fig. 3g).