PMID- 25539728 OWN - NLM STAT- MEDLINE DCOM- 20150821 LR - 20220331 IS - 1471-2407 (Electronic) IS - 1471-2407 (Linking) VI - 14 DP - 2014 Dec 24 TI - Genome-wide identification of FoxO-dependent gene networks in skeletal muscle during C26 cancer cachexia. PG - 997 LID - 10.1186/1471-2407-14-997 [doi] LID - 997 AB - BACKGROUND: Evidence from cachectic cancer patients and animal models of cancer cachexia supports the involvement of Forkhead box O (FoxO) transcription factors in driving cancer-induced skeletal muscle wasting. However, the genome-wide gene networks and associated biological processes regulated by FoxO during cancer cachexia are unknown. We hypothesize that FoxO is a central upstream regulator of diverse gene networks in skeletal muscle during cancer that may act coordinately to promote the wasting phenotype. METHODS: To inhibit endogenous FoxO DNA-binding, we transduced limb and diaphragm muscles of mice with AAV9 containing the cDNA for a dominant negative (d.n.) FoxO protein (or GFP control). The d.n.FoxO construct consists of only the FoxO3a DNA-binding domain that is highly homologous to that of FoxO1 and FoxO4, and which outcompetes and blocks endogenous FoxO DNA binding. Mice were subsequently inoculated with Colon-26 (C26) cells and muscles harvested 26 days later. RESULTS: Blocking FoxO prevented C26-induced muscle fiber atrophy of both locomotor muscles and the diaphragm and significantly spared force deficits. This sparing of muscle size and function was associated with the differential regulation of 543 transcripts (out of 2,093) which changed in response to C26. Bioinformatics analysis of upregulated gene transcripts that required FoxO revealed enrichment of the proteasome, AP-1 and IL-6 pathways, and included several atrophy-related transcription factors, including Stat3, Fos, and Cebpb. FoxO was also necessary for the cancer-induced downregulation of several gene transcripts that were enriched for extracellular matrix and sarcomere protein-encoding genes. We validated these findings in limb muscles and the diaphragm through qRT-PCR, and further demonstrate that FoxO1 and/or FoxO3a are sufficient to increase Stat3, Fos, Cebpb, and the C/EBPbeta target gene, Ubr2. Analysis of the Cebpb proximal promoter revealed two bona fide FoxO binding elements, which we further establish are necessary for Cebpb promoter activation in response to IL-6, a predominant cytokine in the C26 cancer model. CONCLUSIONS: These findings provide new evidence that FoxO-dependent transcription is a central node controlling diverse gene networks in skeletal muscle during cancer cachexia, and identifies novel candidate genes and networks for further investigation as causative factors in cancer-induced wasting. FAU - Judge, Sarah M AU - Judge SM AD - Department of Physical Therapy, University of Florida, 1225 Center Drive, HPNP Building 1142, Gainesville, Florida, USA. smsenf@ufl.edu. FAU - Wu, Chia-Ling AU - Wu CL AD - Department of Health Sciences, Boston University, Boston, Massachusetts, USA. clwu@bu.edu. FAU - Beharry, Adam W AU - Beharry AW AD - Department of Physical Therapy, University of Florida, 1225 Center Drive, HPNP Building 1142, Gainesville, Florida, USA. beharrya1@phhp.ufl.edu. FAU - Roberts, Brandon M AU - Roberts BM AD - Department of Physical Therapy, University of Florida, 1225 Center Drive, HPNP Building 1142, Gainesville, Florida, USA. brob21@ufl.edu. FAU - Ferreira, Leonardo F AU - Ferreira LF AD - Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, Florida, USA. ferreira@hhp.ufl.edu. FAU - Kandarian, Susan C AU - Kandarian SC AD - Department of Health Sciences, Boston University, Boston, Massachusetts, USA. skandar@bu.edu. FAU - Judge, Andrew R AU - Judge AR AD - Department of Physical Therapy, University of Florida, 1225 Center Drive, HPNP Building 1142, Gainesville, Florida, USA. arjudge@phhp.ufl.edu. LA - eng GR - R01 AR060217/AR/NIAMS NIH HHS/United States GR - R01 AR060209/AR/NIAMS NIH HHS/United States GR - T32 HD043730/HD/NICHD NIH HHS/United States GR - R00 HL098453/HL/NHLBI NIH HHS/United States GR - R00HL098453/HL/NHLBI NIH HHS/United States GR - R01AR060209/AR/NIAMS NIH HHS/United States GR - R01AR060217/AR/NIAMS NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural DEP - 20141224 PL - England TA - BMC Cancer JT - BMC cancer JID - 100967800 RN - 0 (Forkhead Transcription Factors) RN - 0 (Transcription Factors) RN - EC 3.4.25.1 (Proteasome Endopeptidase Complex) SB - IM MH - Amino Acid Sequence MH - Animals MH - Cachexia/*etiology MH - Colonic Neoplasms/*complications/*genetics MH - Dependovirus/genetics MH - Disease Models, Animal MH - Extracellular Matrix/metabolism MH - Forkhead Transcription Factors/chemistry/genetics/*metabolism MH - Gene Expression Profiling MH - Gene Expression Regulation MH - *Gene Regulatory Networks MH - Genetic Vectors/genetics MH - *Genome-Wide Association Study MH - Heterografts MH - Humans MH - Male MH - Mice MH - Molecular Sequence Data MH - Muscle, Skeletal/*metabolism MH - Proteasome Endopeptidase Complex/metabolism MH - Reproducibility of Results MH - Sequence Alignment MH - Transcription Factors/genetics/metabolism MH - Transduction, Genetic PMC - PMC4391468 EDAT- 2014/12/30 06:00 MHDA- 2015/08/22 06:00 PMCR- 2014/12/24 CRDT- 2014/12/26 06:00 PHST- 2014/09/22 00:00 [received] PHST- 2014/12/11 00:00 [accepted] PHST- 2014/12/26 06:00 [entrez] PHST- 2014/12/30 06:00 [pubmed] PHST- 2015/08/22 06:00 [medline] PHST- 2014/12/24 00:00 [pmc-release] AID - 1471-2407-14-997 [pii] AID - 5246 [pii] AID - 10.1186/1471-2407-14-997 [doi] PST - epublish SO - BMC Cancer. 2014 Dec 24;14:997. doi: 10.1186/1471-2407-14-997.