Stress can alter immunological, neurochemical and endocrinological functions, but its role in cancer progression is not well understood. Here, we show that chronic behavioral stress results in higher levels of tissue catecholamines, greater tumor burden and more invasive growth of ovarian carcinoma cells in an orthotopic mouse model. These effects are mediated primarily through activation of the tumor cell cyclic AMP (cAMP)-protein kinase A (PKA) signaling pathway by the beta(2) adrenergic receptor (encoded by ADRB2). Tumors in stressed animals showed markedly increased vascularization and enhanced expression of VEGF, MMP2 and MMP9, and we found that angiogenic processes mediated the effects of stress on tumor growth in vivo. These data identify beta-adrenergic activation of the cAMP-PKA signaling pathway as a major mechanism by which behavioral stress can enhance tumor angiogenesis in vivo and thereby promote malignant cell growth. These data also suggest that blocking ADRB-mediated angiogenesis could have therapeutic implications for the management of ovarian cancer.

Purpose: There is growing evidence that stress and other behavioral factors may affect cancer progression and patient survival.The underlying mechanisms for this association are poorly understood.The purpose of this study is to determine the effects of stress-associated hormones norepinephrine, epinephrine, and cortisol on the invasive potential of ovarian cancer cells. Experimental Design:The ovarian cancer cells EG, SKOV3, and 222 were exposed to increasing levels of either norepinephrine, epinephrine, or cortisol, and the in vitro invasive potential was determined using the membrane invasion culture system. Additionally, the effects of these stress hormones on matrix metalloproteinase-2 (MMP-2) and MMP-9 were determined by ELISA. The effects of the h-adrenergic agonist isoproterenol on in vivo tumor growth were determined using nude mice. Results: Stress levels of norepinephrine increased the in vitro invasiveness of ovarian cancer cells by 89% to 198%. Epinephrine also induced significant increases in invasion in all three cell lines ranging from 64% to 76%. Cortisol did not significantly affect invasiveness of the EG and 222 cell lines but increased invasion in the SKOV3 cell line (P = 0.01). We have previously shown that ovarian cancer cells express h-adrenergic receptors. The h-adrenergic antagonist propanolol (1 Amol/L) completely blocked the norepinephrine-induced increase in invasiveness. Norepinephrine also increased tumor cell expression of MMP-2 (P = 0.02 for both SKOV3 and EG cells) and MMP-9 (P = 0.01and 0.04, respectively), and pharmacologic blockade of MMPs abrogated the effects of norepinephrine on tumor cell invasive potential. Isoproterenol treatment resulted in a significant increase in tumor volume and infiltration in the SKOV3ip1 in vivo model, which was blocked by propranolol. Conclusions: These findings provide direct experimental evidence that stress hormones can enhance the invasive potential of ovarian cancer cells. These effects are most likely mediated by stimulation of MMPs.There is extensive evidence supporting stress-immune relationships in healthy adults (1) and a growing body of literature demonstrating these relationships in cancer patients (2 -4). Meta-analyses and reviews have reported alterations in cellular immunity (decreased T-cell response to mitogen stimulation, decreased natural killer cell cytotoxicity, and altered production of cytokines) in association with chronic stress and/or depressed affect (5, 6). Among cancer patients, behavioral factors may serve as predictors of clinical outcome, such as response to therapy and overall survival (7 -11). These findings suggest that psychosocial stress factors not only affect the immune system adversely but also contribute to poor outcome in cancer patients. However, no study has shown that stressinduced changes in cancer outcomes are mediated by changes in immune system function. Here, we consider the alternative hypothesis that stress hormones directly affect tumor cells to alter their malignant potential.Immune s...

Purpose: EphA2 (epithelial cell kinase) is a transmembrane receptor tyrosine kinase that has been implicated in oncogenesis. There are no published data regarding the role of EphA2 in ovarian carcinoma, which is the focus of the present study.Experimental Design: Nontransformed (HIO-180) and ovarian cancer (EG, 222, SKOV3, and A2780-PAR) cell lines were evaluated for EphA2 by Western blot analysis. Five benign ovarian masses, 10 ovarian tumors of low malignant potential, and 79 invasive ovarian carcinomas were also evaluated for EphA2 expression by immunohistochemistry. All samples were scored in a blinded fashion. Univariate and multivariate analyses were used to determine significant associations between EphA2 expression and clinicopathological variables.Results: By Western blot analysis, EG, 222, and SKOV3 cell lines overexpressed EphA2, whereas A2780-PAR and HIO-180 had low to absent EphA2 expression. All of the benign tumors had low or absent EphA2 expression. Among the invasive ovarian carcinomas examined (mean age of patients was 59.2 years), 60 (75.9%) tumors overexpressed EphA2 and the other 19 tumors had negative or minimal EphA2 expression. There was no association of EphA2 overexpression with ascites, likelihood of nodal positivity, pathological subtype, and optimum surgical cytoreduction (residual tumor <1 cm). However, EphA2 overexpression was significantly associated with higher tumor grade (P ‫؍‬ 0.02) and advanced stage of disease (P ‫؍‬ 0.001). The median survival for patients with tumor EphA2 overexpression was significantly shorter (median, 3.1 years; P ‫؍‬ 0.004); the median survival for patients with low or absent EphA2 tumor expression was at least 12 years and has not yet been reached. In multivariate analysis using the Cox proportional hazards model, only volume of residual disease (P < 0.04) and EphA2 overexpression (P < 0.01) were significant and independent predictors of survival.Conclusions: EphA2 overexpression is predictive of aggressive ovarian cancer behavior and may be an important therapeutic target.

BACKGROUND Preclinical evidence suggests that sustained adrenergic activation can promote ovarian cancer growth and metastasis. We examined the impact of beta-adrenergic blockade on clinical outcome of women with epithelial ovarian, primary peritoneal or fallopian tube cancers (collectively, EOC). METHODS A multicenter review of 1,425 women with histopathologically confirmed EOC was performed. Comparisons were made between patients with documented beta blocker use during chemotherapy and those without beta blocker use. RESULTS The median age of patients in this study was 63 years (range, 21–93 years). The sample included 269 patients who received beta blockers. Of those, 193 (71.7%) were receiving beta-1 adrenergic receptor (ADRB1) selective agents, and the remaining patients were receiving non-selective beta antagonists. The primary indication for beta blocker use was hypertension but also included arrhythmia and post-myocardial infarction management. For patients receiving any beta blocker, the median overall survival (OS) was 47.8 months versus42 months (P = 0.04) for non-users. The median OS based on beta blocker receptor selectivity was 94.9 months for those receiving non-selective beta blockers versus 38 months for those receiving ADRB1 selective agents (P < 0.001). Hypertension was associated with decreased OS compared to no hypertension across all groups. However, even in patients with hypertension, users of a non-selective beta blocker had a longer median OS than non-users observed (38.2 vs 90 months, P < 0.001). CONCLUSION Use of non-selective beta blockers in epithelial ovarian cancer patients was associated with longer OS. These findings may have implications for new therapeutic approaches.

EA5 in combination with paclitaxel decreased tumor growth in an orthotopic ovarian cancer mouse model through antiangiogenic mechanisms associated with reduced levels of VEGF and phosphorylated Src. Humanized antibody constructs against EphA2 are worthy of future study.