Given the ability of β-catenin to modulate the anti-cancer immune response, we sought to determine if treatment with RX-5902 could enhance the anti-tumor activity of anti-mouse-PD-1 or anti-mouse-CTLA-4 monoclonal antibodies in an immune-competent BALB/c, 4 T1 mouse model of TNBC [14]. This evidence concerns the gene PDCD1 and cancer.