Non-canonical functions of SNAIL drive context-specific cancer progression
Mariel C. Paul, Christian Schneeweis, Chiara Falcomatà, Chuan Shan, Daniel Rossmeisl, Stella Koutsouli, Christine Klement, Magdalena Zukowska, Sebastian A. Widholz, Moritz Jesinghaus, Konstanze K. Heuermann, Thomas Engleitner, Barbara Seidler, Katia Sleiman, Katja Steiger, Markus Tschurtschenthaler, Benjamin L. Walter, Sören Weidemann, Regina Pietsch, Angelika Schnieke, Roland M. Schmid, María S. Robles, Geoffroy Andrieux, Melanie Boerries, Roland Rad, Günter Schneider, Dieter Saur
Abstract
Abstract SNAIL is a key transcriptional regulator in embryonic development and cancer. Its effects in physiology and disease are believed to be linked to its role as a master regulator of epithelial-to-mesenchymal transition (EMT). Here, we report EMT-independent oncogenic SNAIL functions in cancer. Using genetic models, we systematically interrogated SNAIL effects in various oncogenic backgrounds and tissue types. SNAIL-related phenotypes displayed remarkable tissue- and genetic context-dependencies, ranging from protective effects as observed in KRAS- or WNT-driven intestinal cancers, to dramatic acceleration of tumorigenesis, as shown in KRAS-induced pancreatic cancer. Unexpectedly, SNAIL-driven oncogenesis was not associated with E-cadherin downregulation or induction of an overt EMT program. Instead, we show that SNAIL induces bypass of senescence and cell cycle progression through p16 INK4A -independent inactivation of the Retinoblastoma (RB)-restriction checkpoint. Collectively, our work identifies non-canonical EMT-independent functions of SNAIL and unravel its complex context-dependent role in cancer.