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Dive into the research topics where Patricia C. Ewing is active.

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Featured researches published by Patricia C. Ewing.


The New England Journal of Medicine | 2008

Treatment of Vulvar Intraepithelial Neoplasia with Topical Imiquimod

Manon van Seters; Marc van Beurden; Fiebo J. ten Kate; Ilse Beckmann; Patricia C. Ewing; Marinus J.C. Eijkemans; Marjolein J. Kagie; Chris J. L. M. Meijer; Neil K. Aaronson; Alex Kleinjan; Claudia Heijmans-Antonissen; F. Zijlstra; Matthé P.M. Burger; Theo J.M. Helmerhorst

BACKGROUNDnAlternatives to surgery are needed for the treatment of vulvar intraepithelial neoplasia. We investigated the effectiveness of imiquimod 5% cream, a topical immune-response modulator, for the treatment of this condition.nnnMETHODSnFifty-two patients with grade 2 or 3 vulvar intraepithelial neoplasia were randomly assigned to receive either imiquimod or placebo, applied twice weekly for 16 weeks. The primary outcome was a reduction of more than 25% in lesion size at 20 weeks. Secondary outcomes were histologic regression, clearance of human papillomavirus (HPV) from the lesion, changes in immune cells in the epidermis and dermis of the vulva, relief of symptoms, improvement of quality of life, and durability of response. Reduction in lesion size was classified as complete response (elimination), strong partial response (76 to 99% reduction), weak partial response (26 to 75% reduction), or no response (< or =25% reduction). The follow-up period was 12 months.nnnRESULTSnLesion size was reduced by more than 25% at 20 weeks in 21 of the 26 patients (81%) treated with imiquimod and in none of those treated with placebo (P<0.001). Histologic regression was significantly greater in the imiquimod group than in the placebo group (P<0.001). At baseline, 50 patients (96%) tested positive for HPV DNA. HPV cleared from the lesion in 15 patients in the imiquimod group (58%), as compared with 2 in the placebo group (8%) (P<0.001). The number of immune epidermal cells increased significantly and the number of immune dermal cells decreased significantly with imiquimod as compared with placebo. Imiquimod reduced pruritus and pain at 20 weeks (P=0.008 and P=0.004, respectively) and at 12 months (P=0.04 and P=0.02, respectively). The lesion progressed to invasion (to a depth of <1 mm) in 3 of 49 patients (6%) followed for 12 months (2 in the placebo group and 1 in the imiquimod group). Nine patients, all treated with imiquimod, had a complete response at 20 weeks and remained free from disease at 12 months.nnnCONCLUSIONSnImiquimod is effective in the treatment of vulvar intraepithelial neoplasia. (Current Controlled Trials number, ISRCTN11290871 [controlled-trials.com].).


Journal of Clinical Pathology | 2005

A shift to a peripheral Th2-type cytokine pattern during the carcinogenesis of cervical cancer becomes manifest in CIN III lesions.

Aagje G. Bais; Ilse Beckmann; Jan Lindemans; Patricia C. Ewing; Chris J. L. M. Meijer; Peter J.F. Snijders; Theo J.M. Helmerhorst

Background: A shifted balance between T helper 1 (Th1)-type and Th2-type cytokines has been hypothesised in cervical dysplasia Aims: To evaluate possible deregulation of the cytokine network by estimating the expression of peripheral cytokines in different stages of cervical disease and in relation to the presence or absence of high risk human papillomavirus (HR-HPV). Methods: Twenty one HR-HPV positive women with high grade cervical intraepithelial neoplasia (CIN II–III) and 12 patients with invasive cervical carcinoma formed the study groups. Two control groups consisted of 10 HR-HPV positive and 11 HR-HPV negative women without CIN. Differences in leucocyte subgroups were evaluated by a differential leucocyte count. Plasma concentrations of tumour necrosis factor α (TNFα), TNFα receptors TNFRI and TNFRII, interferon γ (IFNγ), interleukin 2 (IL-2), IL-12, IL-4, and IL-10 were determined by enzyme linked immunosorbent assays. Results: Leucocyte counts in patients with CIN III and carcinoma were significantly higher than in controls. Plasma IFNγ concentrations were significantly lower in patients with CIN III and carcinoma than in women with CIN II or controls. Plasma concentrations of IL-12, IL-2, IL-4, and TNFα did not differ significantly between groups, but significantly lower plasma concentrations of TNFRII were found in CIN III and carcinoma compared with CIN II. IL-10 was detected with increased frequency in the plasma of patients with CIN III and carcinoma. Conclusions: These results indicate that a shift to a Th2-type cytokine pattern during the carcinogenesis of cervical cancer occurs in women with CIN III lesions.


Journal of Investigative Dermatology | 2012

An Autoimmune Phenotype in Vulvar Lichen Sclerosus and Lichen Planus: A Th1 Response and High Levels of MicroRNA-155

Annelinde Terlou; Lindy A.M. Santegoets; Willem I. van der Meijden; Claudia Heijmans-Antonissen; Sigrid M.A. Swagemakers; Peter J. van der Spek; Patricia C. Ewing; Marc van Beurden; Theo J.M. Helmerhorst; Leen J. Blok

Vulvar lichen sclerosus and lichen planus are T-cell-mediated chronic skin disorders. Although autoimmunity has been suggested, the exact pathogenesis of these disorders is still unknown. Therefore, the aim of the current study was to investigate the molecular and immunological mechanisms critical to the pathogenesis of vulvar lichen sclerosus and lichen planus. By using gene expression profiling and real-time RT-PCR experiments, we demonstrated a significantly increased expression of the pro-inflammatory cytokines (IFNγ, CXCR3, CXCL9, CXCL10, CXCL11, CCR5, CCL4, and CCL5) specific for a Th1 IFNγ-induced immune response. In addition, BIC/microRNA-155 (miR-155)--a microRNA involved in regulation of the immune response--was significantly upregulated in lichen sclerosus and lichen planus (9.5- and 17.7-fold change, respectively). Immunohistochemistry showed a significant T-cell response, with pronounced dermal infiltrates of CD4(+), CD8(+), and FOXP3(+) cells. In conclusion, these data demonstrate an autoimmune phenotype in vulvar lichen sclerosus and lichen planus, characterized by increased levels of Th1-specific cytokines, a dense T-cell infiltrate, and enhanced BIC/miR-155 expression.


PLOS ONE | 2012

Progesterone inhibits epithelial-to-mesenchymal transition in endometrial cancer

Paul H. van der Horst; Yongyi Wang; Ingrid Vandenput; Liesbeth C. M. Kühne; Patricia C. Ewing; Wilfred van IJcken; Marten van der Zee; Frédéric Amant; Curt W. Burger; Leen J. Blok

Background Every year approximately 74,000 women die of endometrial cancer, mainly due to recurrent or metastatic disease. The presence of tumor infiltrating lymphocytes (TILs) as well as progesterone receptor (PR) positivity has been correlated with improved prognosis. This study describes two mechanisms by which progesterone inhibits metastatic spread of endometrial cancer: by stimulating T-cell infiltration and by inhibiting epithelial-to-mesenchymal cell transition (EMT). Methodology and Principal Findings Paraffin sections from patients with (nu200a=u200a9) or without (nu200a=u200a9) progressive endometrial cancer (recurrent or metastatic disease) were assessed for the presence of CD4+ (helper), CD8+ (cytotoxic) and Foxp3+ (regulatory) T-lymphocytes and PR expression. Progressive disease was observed to be associated with significant loss of TILs and loss of PR expression. Frozen tumor samples, used for genome-wide expression analysis, showed significant regulation of pathways involved in immunesurveillance, EMT and metastasis. For a number of genes, such as CXCL14, DKK1, DKK4, PEG10 and WIF1, quantitive RT-PCR was performed to verify up- or downregulation in progressive disease. To corroborate the role of progesterone in regulating invasion, Ishikawa(IK) endometrial cancer cell lines stably transfected with PRA (IKPRA), PRB(IKPRB) and PRA+PRB (IKPRAB) were cultured in presence/absence of progesterone (MPA) and used for genome-wide expression analysis, Boyden- and wound healing migration assays, and IHC for known EMT markers. IKPRB and IKPRAB cell lines showed MPA induced inhibition of migration and loss of the mesenchymal marker vimentin at the invasive front of the wound healing assay. Furthermore, pathway analysis of significantly MPA regulated genes showed significant down regulation of important pathways involved in EMT, immunesuppression and metastasis: such as IL6-, TGF-β and Wnt/β-catenin signaling. Conclusion Intact progesterone signaling in non-progressive endometrial cancer seems to be an important factor stimulating immunosurveilance and inhibiting transition from an epithelial to a more mesenchymal, more invasive phenotype.


Mediators of Inflammation | 2007

Cytokine release in HR-HPV(+) women without and with cervical dysplasia (CIN II and III) or carcinoma, compared with HR-HPV(-) controls

Aagje G. Bais; Ilse Beckmann; Patricia C. Ewing; Marinus J.C. Eijkemans; Chris J. L. M. Meijer; Peter J.F. Snijders; Theo J.M. Helmerhorst

Aims. We investigated the effect of HR-HPV infection on the capacity of the cytokine network in whole blood cultures during carcinogenesis of cervical carcinoma. Methods. Thirty-nine women with moderate dysplasia, severe dysplasia, cervical carcinoma, or without dysplasia formed the study group. The control group consisted of 10 HR-HPV-negative women without CIN. Whole blood cultures were stimulated with phytohemagglutinin (PHA) and concentrations of tumour necrosis factor α (TNFα), interferon γ (IFNγ), interleukin 2 (IL-2), interleukin 12 (IL-12), interleukin 4 (IL-4), and interleukin 10 (IL-10) were determined by ELISAs. Results. A significant increase in cytokine release was detected in HR-HPV-positive women without dysplasia. In women with cervical cancer, release of IFNγ and IL-12 was of the same magnitude as in HR-HPV-positive women without clinical manifestations. Most Th1-type/Th2-type ratios decreased form CIN II to CIN III, and increased from CIN III to invasive carcinoma. Conclusions. (1) Infection with HR-HPV without expression of cervical dysplasia induces activation of the cytokine network. (2) Increases in ratios of Th1-type to Th2-type cytokines at the stage of cervical carcinoma were found by comparison with stage CIN III. (3) Significant changes in the kinetics of cytokine release to a Th2-type immune response in blood of women with cervical dysplasia occurred progressively from CIN II to CIN III.


International Journal of Cancer | 2007

HPV related VIN: Highly proliferative and diminished responsiveness to extracellular signals

Lindy A.M. Santegoets; Manon van Seters; Theo J.M. Helmerhorst; Claudia Heijmans-Antonissen; Payman Hanifi-Moghaddam; Patricia C. Ewing; Wilfred van IJcken; Peter J. van der Spek; Willem I. van der Meijden; Leen J. Blok

Vulvar intraepithelial neoplasia (VIN) is a premalignant disorder caused by human papillomaviruses. Basic knowledge about the molecular pathogenesis of VIN is sparse. Therefore, we have analyzed the gene expression profile of 9 VIN samples in comparison to 10 control samples by using genome wide Affymetrix Human U133A plus2 GeneChips. Results were validated by quantitative real‐time RT‐PCR analysis and immunostaining of a few representative genes (TACSTD1, CCNE2, AR and ESR1). Significance analysis of microarrays (SAM) showed that 1,497 genes were differentially expressed in VIN compared to controls. By analyzing the biological processes affected by the observed differences, we found that VIN appears to be a highly proliferative disease; many cyclins (CCNA, CCNB and CCNE) and almost all prereplication complex proteins are upregulated. Thereby, VIN does not seem to depend for its proliferation on paracrine or endocrine signals. Many receptors (for example ESR1 and AR) and ligands are downregulated. Furthermore, although VIN is not an invasive disease, the inhibition of expression of a marked number of cell–cell adhesion molecules seems to indicate development towards invasion. Upon reviewing apoptosis and angiogenesis, it was observed that these processes have not become significantly disregulated in VIN. In conclusion: although VIN is still a premalignant disease, it already displays several hallmarks of cancer.


International Journal of Cancer | 2008

Reduced local immunity in HPV-related VIN: Expression of chemokines and involvement of immunocompetent cells

Lindy A.M. Santegoets; Manon van Seters; Claudia Heijmans-Antonissen; Alex Kleinjan; Marc van Beurden; Patricia C. Ewing; Liesbeth C. M. Kühne; Ilse Beckmann; Curt W. Burger; Theo J.M. Helmerhorst; Leen J. Blok

Usual type VIN is a premalignant disorder caused by persistent HPV infection. High prevalence of VIN in immuno‐suppressed women suggests that a good innate and adaptive immune response is important for defense against HPV. Here, we explored expression levels of chemokines and related these to the presence or absence of immuno‐competent cells (dendritic and T‐cells) in affected (HPV‐positive VIN) and non‐affected (HPV‐negative) vulvar tissues from the same patients. Combining microarray data with quantitative real‐time RT‐PCR, it was observed that several important chemokines were differentially expressed between VIN and control samples (up‐regulation of IL8, CXCL10, CCL20 and CCL22 and down‐regulation of CXCL12, CCL21 and CCL14). Furthermore, an increased number of mature dendritic cells (CD208+) seemed to be bottled up in the dermis, and although a T‐cell response (increased CD4+ and CD8+ cells) was observed in VIN, a much larger response is required to clear the infection. In summary, it seems that most mature dendritic cells do not receive the proper chemokine signal for migration and will stay in the dermis, not able to present viral antigen to naive T‐cells in the lymph node. Consequently the adaptive immune response diminishes, resulting in a persistent HPV infection with increased risk for neoplasia.


Cancer Research | 2008

Disturbed Patterns of Immunocompetent Cells in Usual-Type Vulvar Intraepithelial Neoplasia

van Manon Seters; Ilse Beckmann; Claudia Heijmans-Antonissen; Marc van Beurden; Patricia C. Ewing; F. Zijlstra; Theo J.M. Helmerhorst; Alex Kleinjan

Genital infection with human papillomavirus (HPV) is usually transient, as the immune system is capable of eliminating the virus. When immunity fails and the infection persists, vulvar intraepithelial neoplasia (VIN) may develop. In this study, we examined the distribution of inflammatory cells in 51 patients with HPV-associated usual-type VIN and in 19 healthy controls. Frozen vulvar tissue samples were tested for the presence of HPV-DNA, and immunohistochemical staining for the markers CD1a, CD207, CD208, CD123/CD11c, CD94, CD4, CD8, and CD25/HLA-DR was performed. Cells were counted in both the epidermis and dermis over at least 2 mm of basal membrane length. In the epidermis of VIN patients, CD1a(+) and CD207(+) (Langerin) dendritic cells (DC) and CD8(+) T cells were significantly lower than in controls, whereas the number of CD123(+)/CD11c(-) plasmacytoid DCs (pDC) was significantly increased. No significant changes were observed for CD208(+) DCs, CD94(+) natural killer (NK) cells, CD4(+) T cells, and CD25(+)/HLA-DR(+) regulatory T cells. In the dermis of VIN patients, elevated numbers of CD208(+), CD123(+)/CD11c(-), CD94(+), CD4(+), CD8(+), and CD25(+)/HLA-DR(+) cells were observed when compared with healthy controls. The numbers of CD1a(+) and CD207(+) DCs were not different between groups. In summary, high-risk HPV-related usual-type VIN lesions are characterized by an immunosuppressive state in the epidermis, showing a reduction of immature myeloid DCs (mDC) and CD8(+) T cells. In the dermis, inflammatory activation is reflected by the influx of mature mDCs and pDCs, NK cells, and T cells, suggesting that the cellular immune response on viral HPV infection occurs in the dermis of VIN patients.


Molecular and Cellular Endocrinology | 2011

Loss of APC function in mesenchymal cells surrounding the Müllerian duct leads to myometrial defects in adult mice.

Yongyi Wang; Yundan Jia; Patrick Franken; Ron Smits; Patricia C. Ewing; John P. Lydon; Francesco J. DeMayo; Curt W. Burger; J. Anton Grootegoed; Riccardo Fodde; Leen J. Blok

The WNT signal transduction pathway plays a rate limiting role in early development of many different organs. To study the functional consequences of constitutive activation of the canonical WNT pathway in the developing uterus, we generated a novel mouse model where loss of the tumor suppressor gene Apc was induced. A mouse model was generated and evaluated where Amhr2(Cre/+) driven loss of Apc exon 15 was induced. The Apc recombination was detected mainly in the myometrial layer of the adult uterus. A significant loss of muscle fibers in myometrium was apparent, though with very few muscle cells earmarked by nuclear β-catenin. The finding was confirmed in the Pgr(Cre/+);Apc(15lox/15lox) mouse model. Loss of APC function in mesenchymal cells surrounding the fetal Müllerian ducts results in severe defects in the myometrial layers of the uterus in adult mice, suggesting that the WNT signaling pathway plays important roles in maintaining myometrial integrity.


International Journal of Cancer | 2014

A mouse model for endometrioid ovarian cancer arising from the distal oviduct.

Paul H. van der Horst; Marten van der Zee; Claudia Heijmans-Antonissen; Yundan Jia; Francesco J. DeMayo; John P. Lydon; Carolien H.M. van Deurzen; Patricia C. Ewing; Curt W. Burger; Leen J. Blok

Ovarian cancer is the deadliest gynecological malignancy in Western countries. Early detection, however, is hampered by the fact that the origin of ovarian cancer remains unclear. Knowing that in a high percentage of endometrioid ovarian cancers Wnt/β‐catenin signaling is activated, and in view of the hypothesis that ovarian cancer may originate from the distal oviduct, we studied mice in which Wnt/β‐catenin signaling was activated in Müllerian duct‐derived tissues. Conditional adenomatous polyposis coli (Apc) knockout mice were used to study the activation of Wnt/β‐catenin signaling in Müllerian duct‐derived organs. These PgrCre/+;Apcex15lox/lox mice (nu2009=u200944) were sacrificed at 10, 20, 40 and 80 weeks and uterus, oviduct, ovaries and surrounding fat tissues were assessed using immunohistochemistry. Using nuclear β‐catenin staining, Wnt/β‐catenin signaling activation was confirmed in the entire epithelium of the adult Müllerian duct (fimbriae, oviduct and endometrium), but was absent in ovarian surface epithelium cells (OSEs). Besides endometrial hyperplasia, in 87.2% of mice intraepithelial lesions of the distal oviduct were found, whereas OSEs remained unaffected. In addition, 62.5% of mice developed tumors in the distal and fimbrial part of the oviduct. In the ovaries, mainly at young age, in 16.3% of mice, simple epithelial cysts were noted, which developed further into endometrioid ovarian tumors, resembling human endometrioid ovarian cancer (27.9% of mice). Next to this, locoregional growth in the utero‐ovarian ligament was also shown. Here, for the first time, mutations (activation of Wnt/β‐catenin) in the distal oviduct result in precursor lesions that develop into ovarian tumors, resembling human endometrioid ovarian cancer.

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Curt W. Burger

Erasmus University Rotterdam

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Leen J. Blok

Erasmus University Rotterdam

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Theo J.M. Helmerhorst

Erasmus University Medical Center

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Ilse Beckmann

Erasmus University Rotterdam

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Marc van Beurden

Netherlands Cancer Institute

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Aagje G. Bais

Erasmus University Rotterdam

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Alex Kleinjan

Erasmus University Medical Center

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Liesbeth C. M. Kühne

Erasmus University Medical Center

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