GCG and cancer: For KEGG analysis, genes were significantly enriched in citrate cycle (TCA cycle), HIF-1 signaling pathway, pyruvate metabolism, glycolysis/gluconeogenesis propanoate metabolism, valine, glucagon signaling pathway, leucine and isoleucine degradation, diabetic cardiomyopathy, glyoxylate and dicarboxylate metabolism, and central carbon metabolism in cancer (Figure 7).