Snai2 influences breast cancer evolution in a non-cell autonomous manner. Snai2 influences breast cancer evolution in a non-cell autonomous manner

SNAI2 is a transcription factor involved in multiple processes in both physiology and pathology, including apoptosis, epithelial-mesenchymal transition and tumorigenesis. The effects of SNAI2 on the epithelial compartment have been interpreted as an effect of its expression and action in that compartment. In this work, we demonstrated that the absence of Snai2 in other compartments has repercussions in different aspects of the behavior of the epithelial cells of luminal breast tumors, developed by MMTV-ErbB2/Neu transgenic mice that do not express SNAI2 in the epithelial component. The absent of SNAI2 in the stroma of these tumors is accompanied by different characteristics at histopathological and molecular levels than those having functional SNAI2. These results indicate that the expression of SNAI2 in the tumor niche contributes to the luminal tumor development and behavior. Overall design: Mice were housed at the Animal Research Core Facility of the University of Salamanca. FVB/N-Tg(MMTVneu)202Mul/J, carrying the ErbB2 protooncogene (Guy et al., 1992) were obtained from the Jackson Laboratory. B6;129S1-Snai2tm2Grid/J Snai2-deficient mice were generated by Dr. Gridley (Jiang et al., 1998) To generate the parous cohort, Snai2 WT ERBB2+ and Snai2 KO