Objective: EphA2 overexpression predicts poor prognosis in endometrial cancer. To explore mechanisms for this association and assess its potential as therapeutic target, the relationship of EphA2 expression to markers of angiogenesis was examined using patient samples and an orthotopic mouse model of uterine cancer.
Experimental Design: Expression of EphA2, estrogen receptor (ER), progesterone receptor (PR), Ki-67, vascular endothelial growth factor (VEGF) and microvessel density (MVD) was evaluated using immunohistochemistry in 85 endometrioid endometrial adenocarcinomas (EEC) by two independent investigators.
Objective: To estimate the incidence of venous thromboembolism among patients undergoing gynecologic laparoscopy and characterize the risk of venous thromboembolism among patients with gynecologic malignancy.
Methods: Data were collected for patients who underwent laparoscopic gynecologic surgery from January 2000 to January 2009. Incidence of deep vein thrombosis (DVT) or pulmonary embolism diagnosed within 6 weeks of surgery was estimated.
Although VEGF-targeted therapies are showing promise, new angiogenesis targets are needed to make additional gains. Here, we show that increased Zeste homolog 2 (EZH2) expression in either tumor cells or in tumor vasculature is predictive of poor clinical outcome. The increase in endothelial EZH2 is a direct result of VEGF stimulation by a paracrine circuit that promotes angiogenesis by methylating and silencing vasohibin1 (vash1).
View Article and Find Full Text PDFEphB4 is a transmembrane receptor tyrosine kinase that plays an important role in neural plasticity and angiogenesis. EphB4 is overexpressed in ovarian cancer and is predictive of poor clinical outcome. However, the biological significance of EphB4 in ovarian cancer is not known and is the focus of the current study.
View Article and Find Full Text PDFChronic stress is associated with hormonal changes that are known to affect multiple systems, including the immune and endocrine systems, but the effects of stress on cancer growth and progression are not fully understood. Here, we demonstrate that human ovarian cancer cells exposed to either norepinephrine or epinephrine exhibit lower levels of anoikis, the process by which cells enter apoptosis when separated from ECM and neighboring cells. In an orthotopic mouse model of human ovarian cancer, restraint stress and the associated increases in norepinephrine and epinephrine protected the tumor cells from anoikis and promoted their growth by activating focal adhesion kinase (FAK).
View Article and Find Full Text PDFThis study aimed to investigate the antitumor and antiangiogenic effects utilizing a novel therapy regimen of metronomic topotecan and pazopanib, a multireceptor tyrosine kinase inhibitor. In vitro (Western blot) and in vivo dose-finding experiments were done following pazopanib therapy in ovarian cancer models. Pazopanib and metronomic (daily) oral topotecan therapy was examined in an orthotopic model of ovarian cancer.
View Article and Find Full Text PDFImportance Of The Field: Ovarian cancer is the leading cause of death from a gynecologic malignancy. Recurrence is both common and lethal, necessitating the development of novel targeted therapies. Farletuzumab (MORAb-003) is a humanized mAb with high affinity for folate receptor alpha (FRalpha), a 38 kDa GPI-anchored protein that is overexpressed in 90% of epithelial ovarian cancers.
View Article and Find Full Text PDFPurpose: Metronomic chemotherapy regimens have shown anti-tumor activity by anti-angiogenic mechanisms, however, the efficacy of metronomic topotecan in ovarian cancer is not known and the focus of the current study.
Experimental Design: In vivo dose-finding and therapy experiments with oral metronomic topotecan were performed in an orthotopic model of advanced ovarian cancer. Tumor vascularity (MVD: CD31), proliferation (PCNA) and apoptosis (TUNEL) were examined among treatment arms.
Purpose: Resistance to platinum chemotherapy remains a significant problem in ovarian carcinoma. Here, we examined the biological mechanisms and therapeutic potential of targeting a critical platinum resistance gene, ATP7B, using both in vitro and in vivo models.
Experimental Design: Expression of ATP7A and ATP7B was examined in ovarian cancer cell lines by real-time reverse transcription-PCR and Western blot analysis.
Purpose: The effects of reproductive hormones on ovarian cancer growth are not well understood. Here, we examined the effects of estrous cycle variation and specific reproductive hormones on ovarian cancer growth.
Experimental Design: We investigated the role of reproductive hormones in ovarian cancer growth using both in vivo and in vitro models of tumor growth.
Background: We studied Dicer and Drosha, components of the RNA-interference machinery, in ovarian cancer.
Methods: We measured messenger RNA (mRNA) levels of Dicer and Drosha in specimens of invasive epithelial ovarian cancer from 111 patients, using a quantitative reverse-transcriptase-polymerase-chain-reaction assay, and compared the results with clinical outcomes. Validation was performed with the use of published microarray data from cohorts of patients with ovarian, breast, and lung cancer.
Vascular endothelial growth factor receptor (VEGFR) has recently been discovered on ovarian cancer cells, but its functional significance is unknown and is the focus of this study. By protein analysis, A2780-par and HeyA8 ovarian cancer cell lines expressed VEGFR-1 and HeyA8 A2774, and SKOV3ip1 expressed VEGFR-2. By in situ hybridization (ISH), 85% of human ovarian cancer specimens showed moderate to high VEGFR-2 expression, whereas only 15% showed moderate to high VEGFR-1 expression.
View Article and Find Full Text PDFThe alpha(v)beta(3) integrin is expressed on proliferating endothelial cells and some cancer cells, but its expression on ovarian cancer cells and its potential as a therapeutic target are unknown. In this study, expression of the alpha(v)beta(3) integrin on ovarian cancer cell lines and murine endothelial cells was tested, and the effect of a fully humanized monoclonal antibody against alpha(v)beta(3), Abegrin (etaracizumab), on cell invasion, viability, tumor growth, and the Akt pathway were examined in vitro and in vivo. We found that etaracizumab recognizes alpha(v)beta(3) on the ovarian cancer cell lines SKOV3ip1, HeyA8, and A2780ip2 (at low levels) but not on murine endothelial cells.
View Article and Find Full Text PDFPurpose: The Aurora kinase family plays pivotal roles in mitotic integrity and cell cycle. We sought to determine the effects of inhibiting Aurora kinase on ovarian cancer growth in an orthotopic mouse model using a small molecule pan-Aurora kinase inhibitor, MK-0457.
Experimental Design: We examined cell cycle regulatory effects and ascertained the therapeutic efficacy of Aurora kinase inhibition both alone and combined with docetaxel using both in vitro and in vivo ovarian cancer models.
Tissue type transglutaminase (TG2) is a unique multifunctional protein that plays a role in many steps in the cancer metastatic cascade. Here, we examined the clinical (n = 93 epithelial ovarian cancers) and biological (in vitro adhesion, invasion, and survival and in vivo therapeutic targeting) significance of TG2 in ovarian cancer. The overexpression of TG2 was associated with significantly worse overall patient survival in both univariate and multivariate analyses.
View Article and Find Full Text PDFPurpose: Defects in the antigen processing machinery (APM) may provide tumor cells with a mechanism to escape immune recognition. The purpose of this study is to determine the clinical significance of APM component down-regulation and tumor-infiltrating T cells in ovarian carcinoma.
Experimental Design: After institutional review board approval, tumor samples from 150 patients with invasive epithelial ovarian cancers were examined for TAP1, TAP2, tapasin, HLA class I heavy chain (HLA-HC), beta 2 microglobulin, and T-cell (CD3+ and CD8+) tumor infiltration using immunohistochemistry.
Background: Interleukin-8 (IL-8) is a proangiogenic cytokine that is overexpressed in many human cancers. We investigated the clinical and biologic significance of IL-8 in ovarian carcinoma using human samples and orthotopic mouse models.
Methods: Tumor expression of IL-8 was assessed by immunohistochemistry among ovarian cancer patients (n = 102) with available clinical and survival data.
Angiogenesis is a complex and highly regulated process that is crucial for tumor growth and metastasis. Insights into the molecular mechanisms of tumor angiogenesis have led to the identification of potential angiogenic targets and the development of novel antivascular agents. Many of these agents are being evaluated in clinical trials and have shown promising antitumor activity.
View Article and Find Full Text PDFPurpose: Vascular endothelial growth factor (VEGF) is critical for angiogenesis and tumor progression; however, its role in endometrial cancer is not fully known. Therefore, we examined the clinical and therapeutic significance of VEGF in endometrial carcinoma using patient samples and an endometrioid orthotopic mouse model.
Experimental Design: Following Institutional Review Board approval, VEGF expression and microvessel density (MVD) counts were evaluated using immunohistochemistry in 111 invasive endometrioid endometrial cancers by two independent investigators.
Focal adhesion kinase (FAK) overexpression is frequently found in ovarian and other cancers and is predictive of poor clinical outcome. In the current study, we characterized the biological and therapeutic effects of a novel FAK inhibitor, TAE226. Taxane-sensitive (SKOV3ip1 and HeyA8) and taxane-resistant (HeyA8-MDR) cell lines were used for in vitro and in vivo therapy experiments using TAE226 alone and in combination with docetaxel.
View Article and Find Full Text PDFThere is growing evidence that chronic stress and other behavioral conditions are associated with cancer pathogenesis and progression, but the mechanisms involved in this association are poorly understood. We examined the effects of two mediators of stress, norepinephrine and epinephrine, on the activation of signal transducer and activator of transcription-3 (STAT3), a transcription factor that contributes to many promalignant pathways. Exposure of ovarian cancer cell lines to increasing concentrations of norepinephrine or epinephrine showed that both independently increased levels of phosphorylated STAT3 in a dose-dependent fashion.
View Article and Find Full Text PDFThe purpose of this study was to examine the therapeutic efficacy and underlying mechanisms of action of a vascular-disrupting agent, AVE8062, and to determine its effects on tumor metabolic activity. The in vitro and in vivo effects of AVE8062 alone and in combination with docetaxel were tested in chemotherapy-sensitive and chemotherapy-resistant ovarian cancer models. Tumors were analyzed for necrosis, microvessel density, endothelial cell apoptosis, and proliferation following treatment.
View Article and Find Full Text PDFPurpose: To assess the clinical significance of Aurora-A kinase, a centrosome-regulating serine-threonine kinase, in ovarian carcinoma.
Experimental Design: Aurora-A kinase expression was assessed by Western blot (cell lines) or immunohistochemistry (high-grade epithelial ovarian cancers), and clinical variables were collected by retrospective chart review. Centrosome amplification was assessed by immunofluorescence in cell lines, and by immunohistochemistry in patient samples.
Purpose: Curcumin, a component of turmeric, has been shown to suppress inflammation and angiogenesis largely by inhibiting the transcription factor nuclear factor-kappaB (NF-kappaB). 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.