By: LaShanale Wallace

 Introduction: What is Autophagy?  Objective  Specific examples  Conclusion

 A vital cellular process by which intracellular components are degraded within the lysosome  An essential for survival, differentiation, development, and homeostasis

 Is to ensure cell survival through unfavorable situations ex….  Nutrient absence  Growth factor withdraw  Abundant amount of toxic proteins  Defected organells

 The Roles of Autophagy in life and disease

 Focusing on the dual roles of autophagy  Specific examples are… 1. Its role as cytoprotective autophagy 2. Its role in skeletal muscle and aging 3. And its role in pancreatic cancer

 Purpose  Investigate expression pattern and sublocalization of caspase 8 in TRAIL mediated autophagy  Expression of caspase 8 in shift from autophagy to apoptosis  Materials  HCT colon carcinoma cells treated with TRAIL

 Method  Quantitative image cytometry,  Confocal microscopy assay.  Immunoblot  Inhibition of autophagy induces caspase 8 activity  Cleaved caspase 8 localizes to autophagosome, inhibiting apoptosis

 This study provides evidence for regulation of caspase 8 activity through autophagy  Capase 8 provides a cross talk mechanism between autophagy and apoptosis

 Purpose  Does autophagy in skeletal muscle change with age?  Does exercise and calorie restriction have an effect on autophagy?  Materials  Male Fisher Rats  Ad libthium diet  Four groups: Y,O, OCR, and OCREX  Fast twitch muscle tissue

 Results  Autophagy decreases with age.  Calorie restriction increased autophagy response  Exercise had no significant effect

 Age is associated with lower levels of autophagy. This leads to increased cellular damage and apoptosis causing muscle loss.  Mild calorie restricted diets increased autophagy in older rats, protecting muscle from cell damage and death

 Purpose  Demonstrate that pancreatic cancers are dependent on autophagy for growth  Pancreatic tumor cells are sensitive to autophagy inhibition

 Pancreatic ductal adenocarcinoma cells(PDAC)  Control cell lines MCF7, H460, AND HPDE  GFP-LC3 assay  Chloroquine inhibitor  Assay determined degree of autophagy  Immunochemistry monitored LC3 expression during tumor progression  CQ Treatment

 PDAC has high levels of basal autophagy  Autophagy is upregulated during tumor progression  PDAC is sensitive to CQ treatment  PDAC Mice treated with CQ live longer

 Since PDAC is dependent on autophagy, this provides a potential target for therapeutic intervention  Since chloroquine is already used as a anti- malaria therapeutic, clinical trials using drugs targeting autophagy inhibition are strongly suggested for pancreatic cancer

 Functions of autophagy can be beneficial are harmful  Its role to promote cell survival….  Is beneficial in life processes such as aging  Harmful in diseases like pancreatic cancer  With knowledge researchers can create therapeutics and either inhibit or increase autophagy pathways for more favorable outcomes.

 Dr. Muganda  MARC Program  Dr. White  Mrs. Petty  Mrs. Sindy Martin

1. Wohlgemuth, S. E., Seo, A. Y., Marzetti, E., Lees, H. A., and Leeuwenburgh, C. Skeletal muscle autophagy and apoptosis during aging: effects of calorie restriction and life-long exercise. Experimental Gerontology 2010; 45: Young M, T. Y., Khan O, Park S, Hori T, Yun J, Amin S, Hu C, Zhang J, Kester M, and Wang H. Autophagosomal membrane serves as a platform for an intracellular death-inducing signaling complex (iDISC)-mediated caspase-8 activation and apoptosis. The Journal of Biological Chemistry. 2012; 287: Rosenfeldt MT, Ryan KM. The multiple roles of autophagy in cancer. Carcinogenesis. 2011; 32(7): html 6. ar-Probes-The-Handbook/Assays-for-Cell-Viability-Proliferation- and-Function/Assays-for-Apoptosis.html#head /