Epithelial TGFβ engages growth-factor signalling to circumvent apoptosis and drive intestinal tumourigenesis with aggressive features.
Flanagan DJ., Amirkhah R., Vincent DF., Gundaz N., Gentaz P., Cammareri P., McCooey AJ., McCorry AMB., Fisher NC., Davis HL., Ridgway RA., Lohuis J., Leach JDG., Jackstadt R., Gilroy K., Mariella E., Nixon C., Clark W., Hedley A., Markert EK., Strathdee D., Bartholin L., Redmond KL., Kerr EM., Longley DB., Ginty F., Cho S., Coleman HG., Loughrey MB., Bardelli A., Maughan TS., Campbell AD., Lawler M., Leedham SJ., Barry ST., Inman GJ., van Rheenen J., Dunne PD., Sansom OJ.
The pro-tumourigenic role of epithelial TGFβ signalling in colorectal cancer (CRC) is controversial. Here, we identify a cohort of born to be bad early-stage (T1) colorectal tumours, with aggressive features and a propensity to disseminate early, that are characterised by high epithelial cell-intrinsic TGFβ signalling. In the presence of concurrent Apc and Kras mutations, activation of epithelial TGFβ signalling rampantly accelerates tumourigenesis and share transcriptional signatures with those of the born to be bad T1 human tumours and predicts recurrence in stage II CRC. Mechanistically, epithelial TGFβ signalling induces a growth-promoting EGFR-signalling module that synergises with mutant APC and KRAS to drive MAPK signalling that re-sensitise tumour cells to MEK and/or EGFR inhibitors. Together, we identify epithelial TGFβ signalling both as a determinant of early dissemination and a potential therapeutic vulnerability of CRC's with born to be bad traits.