Cancer is the most common comorbidity in septic patients with nearly 93,000 cases annually. Importantly, cancer is also the comorbidity associated with the highest risk of death in patients with sepsis. We have created a murine model that replicates the increased mortality seen in septic patients with cancer compared to previously healthy patients who develop sepsis. The first goal of this proposal is to understand possible mechanisms through which pre-existing cancer increases mortality when a host develops sepsis. Based upon preliminary data, both the immune system and gut integrity appear to be involved, so each of these will be examined in detail. Experiments will be performed in multiple models of sepsis with multiple tumor lines to determine whether results are generalizable or specific to either type of sepsis or type of cancer. Additionally, there is extensive data from multiple investigative groups that apoptosis prevention in either lymphocytes or the gut epithelium improves survival in previously health rodents with sepsis. However, when this strategy is used in septic mice with cancer, the precise opposite is found with apoptosis prevention either markedly increasing mortality (lymphocytes) or losing its efficacy (intestine). The proposal seeks to understand why a beneficial therapy that has widespread acceptance as a possible treatment approach for patients turns deadly if sepsis occurs in the setting of cancer. Since efforts are currently being made to translate apoptosis prevention into treatment that can be used at the bedside for septic patients, this proposal could potentially change entry criteria and/or prevent inadvertent mortality in patients undergoing clinical trials of apoptosis prevention in sepsis. Thus, the proposal seeks to understand a subpopulation within sepsis that may require a different therapeutic approach than a "typical" septic host, and this may have significant implications in a disease that is both very common and highly lethal.

Public Health Relevance

Cancer is the most common comorbidity in septic patients with nearly 93,000 cases annually, and cancer is also the comorbidity associated with the highest risk of death in patients with sepsis. Although apoptosis prevention improves survival in previously health rodents with sepsis, apoptosis prevention markedly increases mortality in septic mice with cancer. Understanding a) why mortality is higher in septic hosts with cancer compared to previously healthy septic hosts and b) why a beneficial therapeutic approach turns deadly if sepsis occurs in the setting of cancer may therefore have significant therapeutic implications in a disease that is both very common and highly lethal.

Agency
National Institute of Health (NIH)
Type
Research Project (R01)
Project #
5R01GM104323-02
Application #
8667486
Study Section
Special Emphasis Panel (ZRG1)
Program Officer
Dunsmore, Sarah
Project Start
Project End
Budget Start
Budget End
Support Year
2
Fiscal Year
2014
Total Cost
Indirect Cost
Name
Emory University
Department
Surgery
Type
Schools of Medicine
DUNS #
City
Atlanta
State
GA
Country
United States
Zip Code
30322
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Liang, Zhe; Xie, Yan; Dominguez, Jessica A et al. (2014) Intestine-specific deletion of microsomal triglyceride transfer protein increases mortality in aged mice. PLoS One 9:e101828
Mittal, Rohit; Coopersmith, Craig M (2014) Redefining the gut as the motor of critical illness. Trends Mol Med 20:214-23
Kharasch, Evan D; Coopersmith, Craig M (2013) Sleeping to survive?: The impact of volatile anesthetics on mortality in sepsis. Anesthesiology 119:755-6