TGFB1 and neoplasm: Together, this indicates that loss of wild-type Kras with epithelial NOTCH1 activation in KPN tumours activates Wnt, restricts the TGFβ mediated neutrophil recruitment required to generate an immunosuppressive, pro-metastatic niche and blunts the metastases of tumours lacking wild-type Kras (Fig. 7f).