Figure 3

Genome-wide identification of gene networks regulated by FoxO in muscles of cachectic C26 tumor-bearing mice. ( A ) Microarray analyses were performed on TA muscles from control and cachectic C26 mice transduced with either AAV9-ev or AAV9-d.n.FoxO. Comparison of control and C26 AAV9-ev groups revealed 2,194 gene transcripts which were differentially expressed in response to C26 (FDR q-value < 0.01 and fold-change ≥ 1.5-fold). Of these genes, 543 genes were differentially regulated in muscles from C26 mice transduced with d.n.FoxO (AAV9-ev C26 vs. AAV9-d.n.FoxO C26, FDR q-value < 0.01 and fold-change ≥ 1.5-fold) and were thus considered as downstream targets (direct or indirect) of FoxO. ( B and C ) Gene transcripts upregulated ( B ) or downregulated ( C ) in response to C26 which were identified as FoxO targets were analyzed using the DAVID functional annotation clustering module and Broad’s Molecular Signature Database to identify enriched biological processes and Canonical Pathways. The top 10 most highly enriched DAVID annotation clusters and MSigDB Canonical Pathways from each gene set are ranked in order of significance and are plotted against the -log of the p-value. ( D and E ) Gene expression changes of select transcripts identified via microarray as downstream targets of FoxO were validated using qRT-PCR analyses. Data represent mean ± SE, n = at least 3 animals/group. *p < 0.05 vs AAV9-ev control group. †p < 0.05 vs. AAV9-ev C26 group.