Given that the activation of cGMP/PKG signaling has been reported to suppress oncogenic Wnt/β-catenin signaling in colon and breast cancer cells by inhibiting β-catenin expression at mRNA level and β-catenin/CTNNB1 promoter levels [14, 32], a similar mechanism may exist in lung tumor cells. This evidence concerns the gene PRKG1 and breast carcinoma.