To assess whether pepck1 knockdown reduces wingless/Wnt signaling in HDS-induced tumor growth, we utilized a specific antibody against wingless to evaluate wingless/Wnt signaling in tumor-bearing animals (rasG12V; csk−/−) and tumor-bearing animals with pepck1 knockdown (rasG12V, pepck1RNAi; csk−/−) fed HDS or NDS. The gene discussed is PCK1; the disease is neoplasm.