Effects of chronic stress on cytokine networks in ovarian cancer ascites (268)

Abstract

Objectives: A cancer diagnosis increases stress hormones and leads to altered psychological states, such as chronic stress. Work from our team suggests that chronic stress promotes an increased inflammatory response. Preliminary data show an altered CD4+/CD8+ T cell ratio and a heterogeneous expression of exhaustion markers in patients with high-grade serous ovarian cancer (HGSOC). Therefore, we hypothesized that chronic stress increases inflammation and an exhausted tumor microenvironment (TME). We sought to characterize the relationship between stress hormones and adrenergic signaling on cytokine networks in ascites from patients with HGSOC. Methods: We obtained ascites samples from 66 patients with HGSOC and 18 ID8 tumor-bearing mice (8 to 12 - week-old C57BL6/7 female mice) subjected to restraint stress. Then, we measured cytokine levels using a comprehensive Cytokine/Chemokine magnetic bead panel. Cortisol, metanephrine, normetanephrine, and corticosterone levels from ascites were measured by ELISA. Results: Results showed a significant increase in inflammatory cytokines in patients with recurrent tumors, including sCD40L (p=0.0319), IL-6 (p=0.0035), VEGF (p=0.0231), Eotaxin (p=0.0005), IL-15 (p=0.0399) and IL-7 (p=0.01). When assessing cytokines and cortisol levels, we found that elevated cortisol was associated with a downregulation of antitumor cytokines: IP-10 (p=0.0162) and IFN-gamma (p=0.0227). Moreover, metanephrine levels were positively correlated with pro-tumoral and inflammatory cytokines: SCD40L (p=0.032, r=0.3234), FGF-2 (p=0.033, r=0.3217) and MIP1a (p=0.03, r=0.3296). Normetanephrine was also moderately correlated with pro-inflammatory cytokines: IL-6 (p<0.0001, r=0.5241), MCP-1 (p=0.0268, r=0.2790), VEGF (p=0.0042, r=0.3560), MCP-3 (p=0.0130, r=0.3114), GRO (p=0.0129, r=0.3116) and IL-7 (p<0.0001, r=0.5287), while FGF-2 (p=0.0080, r=0.3315) was negatively correlated. In addition, corticosterone levels obtained from ascites derived from our animal model were positively correlated with pro-inflammatory cytokines: VEGF (p<0.0001, r=0.88), TNF-alpha (p=0.036, r=0.498) and Eotaxin (p=0.02, r=0.50). These results suggest a role for stress hormones in increased inflammation and immune exhaustion. Conclusions: Ascites from patients with recurrent HGSOC were associated with increased pro-inflammatory cytokines, while elevated cortisol was associated with a downregulation of antitumor cytokines. Similarly, high metanephrine, normetanephrine, and corticosterone levels correlated with increased expression of pro-inflammatory cytokines. These data suggest a role for stress in immunosuppression and may impact the efficacy of therapies that aim to restore T cell function. Objectives: A cancer diagnosis increases stress hormones and leads to altered psychological states, such as chronic stress. Work from our team suggests that chronic stress promotes an increased inflammatory response. Preliminary data show an altered CD4+/CD8+ T cell ratio and a heterogeneous expression of exhaustion markers in patients with high-grade serous ovarian cancer (HGSOC). Therefore, we hypothesized that chronic stress increases inflammation and an exhausted tumor microenvironment (TME). We sought to characterize the relationship between stress hormones and adrenergic signaling on cytokine networks in ascites from patients with HGSOC. Methods: We obtained ascites samples from 66 patients with HGSOC and 18 ID8 tumor-bearing mice (8 to 12 - week-old C57BL6/7 female mice) subjected to restraint stress. Then, we measured cytokine levels using a comprehensive Cytokine/Chemokine magnetic bead panel. Cortisol, metanephrine, normetanephrine, and corticosterone levels from ascites were measured by ELISA. Results: Results showed a significant increase in inflammatory cytokines in patients with recurrent tumors, including sCD40L (p=0.0319), IL-6 (p=0.0035), VEGF (p=0.0231), Eotaxin (p=0.0005), IL-15 (p=0.0399) and IL-7 (p=0.01). When assessing cytokines and cortisol levels, we found that elevated cortisol was associated with a downregulation of antitumor cytokines: IP-10 (p=0.0162) and IFN-gamma (p=0.0227). Moreover, metanephrine levels were positively correlated with pro-tumoral and inflammatory cytokines: SCD40L (p=0.032, r=0.3234), FGF-2 (p=0.033, r=0.3217) and MIP1a (p=0.03, r=0.3296). Normetanephrine was also moderately correlated with pro-inflammatory cytokines: IL-6 (p<0.0001, r=0.5241), MCP-1 (p=0.0268, r=0.2790), VEGF (p=0.0042, r=0.3560), MCP-3 (p=0.0130, r=0.3114), GRO (p=0.0129, r=0.3116) and IL-7 (p<0.0001, r=0.5287), while FGF-2 (p=0.0080, r=0.3315) was negatively correlated. In addition, corticosterone levels obtained from ascites derived from our animal model were positively correlated with pro-inflammatory cytokines: VEGF (p<0.0001, r=0.88), TNF-alpha (p=0.036, r=0.498) and Eotaxin (p=0.02, r=0.50). These results suggest a role for stress hormones in increased inflammation and immune exhaustion. Conclusions: Ascites from patients with recurrent HGSOC were associated with increased pro-inflammatory cytokines, while elevated cortisol was associated with a downregulation of antitumor cytokines. Similarly, high metanephrine, normetanephrine, and corticosterone levels correlated with increased expression of pro-inflammatory cytokines. These data suggest a role for stress in immunosuppression and may impact the efficacy of therapies that aim to restore T cell function.