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.

Background-We studied Dicer and Drosha, components of the RNA-interference machinery, in 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: Curcumin, a component of turmeric, has been shown to suppress inflammation and angiogenesis largely by inhibiting the transcription factor nuclear factor-nB (NF-nB). This study evaluates the effects of curcumin on ovarian cancer growth using an orthotopic murine model of ovarian cancer. Experimental Design: In vitro and in vivo experiments of curcumin with and without docetaxel were done using human ovarian cancer cell lines SKOV3ip1, HeyA8, and HeyA8-MDR in athymic mice. NF-nB modulation was ascertained using electrophoretic mobility shift assay. Evaluation of angiogenic cytokines, cellular proliferation (proliferating cell nuclear antigen), angiogenesis (CD31), and apoptosis (terminal deoxynucleotidyl transferase^mediated dUTP nick end labeling) was done using immunohistochemical analyses. Results: Curcumin inhibited inducible NF-nB activation and suppressed proliferation in vitro. In vivo dose-finding experiments revealed that 500 mg/kg orally was the optimal dose needed to suppress NF-nB and signal transducers and activators of transcription 3 activation and decrease angiogenic cytokine expression. In the SKOV3ip1 and HeyA8 in vivo models, curcumin alone resulted in 49% (P = 0.08) and 55% (P = 0.01) reductions in mean tumor growth compared with controls, whereas when combined with docetaxel elicited 96% (P < 0.001) and 77% reductions in mean tumor growth compared with controls. In mice with multidrugresistant HeyA8-MDR tumors, treatment with curcumin alone and combined with docetaxel resulted in significant 47% and 58% reductions in tumor growth, respectively (P = 0.05). In SKOV3ip1 and HeyA8 tumors, curcumin alone and with docetaxel decreased both proliferation (P < 0.001) and microvessel density (P < 0.001) and increased tumor cell apoptosis (P < 0.05).Conclusions: Based on significant efficacy in preclinical models, curcumin-based therapies may be attractive in patients with ovarian carcinoma.

Purpose: The miR-34 family is directly transactivated by tumor suppressor p53, which is frequently mutated in human epithelial ovarian cancer (EOC). We hypothesized that miR-34 expression would be decreased in EOC and that reconstituted miR-34 expression might reduce cell proliferation and invasion of EOC cells.Experimental Designs: miR-34 expression was determined by quantitative reverse transcription-PCR and in situ hybridization in a panel of 83 human EOC samples. Functional characterization of miR-34 was accomplished by reconstitution of miR-34 expression in EOC cells with synthetic pre-miR molecules followed by determining changes in proliferation, apoptosis, and invasion.Results: miR-34a expression is decreased in 100%, and miR-34b*/c in 72%, of EOC with p53 mutation, whereas miR-34a is also downregulated in 93% of tumors with wild-type p53. Furthermore, expression of miR-34b*/c is significantly reduced in stage IV tumors compared with stage III (P = 0.0171 and P = 0.0029, respectively). Additionally, we observed promoter methylation and copy number variations at mir-34. In situ hybridization showed that miR-34a expression is inversely correlated with MET immunohistochemical staining, consistent with translational inhibition by miR-34a. Finally, miR-34 reconstitution experiments in p53 mutant EOC cells resulted in reduced proliferation, motility, and invasion, the latter of which was dependent on MET expression.Conclusions: Our work suggests that miR-34 family plays an important role in EOC pathogenesis and reduced expression of miR-34b*/c may be particularly important for progression to the most advanced stages. Part of miR-34 effects on motility and invasion may be explained by regulation of MET, which is frequently overexpressed in EOC. Clin Cancer Res; 16(4); 1119-28. ©2010 AACR.Ovarian cancer is the most deadly malignancy and will lead to ∼15,000 deaths in the United States in 2009 (1). Although survival has increased slightly over the past 25 years, 5-year survival remains below 50%. A major factor for low survival is our poor understanding of the initiating events that lead to ovarian cancer and how the disease progresses. Due to asymptomatic development and few screening options, ∼70% of women present at late stages of carcinogenesis. At an advanced stage, treatment options are severely limited, with palliative treatment most often administered in the form of debulking surgery and paclitaxel-and platinum-based therapeutics. However, work over the past decade using human cancer samples and mouse models have revealed new insights into the molecular basis of ovarian cancer, particularly its most common form epithelial ovarian cancer (EOC). For example, it is well established that >50% of highgrade serous-type EOCs contain p53 mutations and alterations in the RB pathway (reviewed in refs. 2, 3). Consistently, conditional inactivation of p53 and Rb in the mouse ovarian surface epithelium (OSE) leads to development of poorly differentiated serous ovarian adenocarcinomas (4), whereas K-Ras, Pten, ...