In the present study, we have examined the interactions between cancer, systemic metabolism, and tumor immunology in mice using two cancer types that have been documented to predispose to cachexia, the transplanted C26 model of colorectal cancer (Tanaka et al., 1990) and the genetically engineered, autochthonous LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx-1-Cre/+ (KPC) model of PDA (Hingorani et al., 2005, Roberts et al., 2013). The gene discussed is PDX1; the disease is cancer.