Fig. 1

Integrin α3β1 is not needed for the onset of HER2-driven mammary tumorigenesis. a Kaplan-Meier plots of tumor-free survival in Itga3 KO and WT mice show that first palpable tumors could be detected at comparable age in both genotypes. b The number of tumors, measured macroscopically over time, was similar between Itga3 KO and WT mice (n = 17). c The western blot of four randomly selected, representative tumors isolated from Itga3 KO and WT mice shows a clear deletion of α3 in Itga3 KO mice. d Representative images of immunohistochemical staining for HER2/Neu in Itga3 KO and WT tumors show its strong expression, which was observed in all the analyzed tumors. e Representative images of immunofluorescent staining show the absence of basal markers β4, keratin 5, and laminin-332, which is also the main ligand for integrin α3β1. E-cadherin, β-catenin, Plet1, collagen I, and keratin 18 were strongly expressed in all tumors. No difference was observed between Itga3 KO and WT mice. Scale bar, 200 μm