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Publications (8)27.98 Total impact

  • Article: Death receptor expression is associated with poor response to chemotherapy and shorter survival in metastatic ovarian carcinoma.
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    ABSTRACT: Death receptors mediate both apoptosis and survival in cancer cells. The authors analyzed death receptor expression in metastatic ovarian carcinoma. Viable tumor cells in ovarian carcinoma effusions (n = 95) were analyzed for DR4, DR5, Fas, TNFR1, and TNFR2 expression using flow cytometry. Results were analyzed for association with clinicopathologic parameters, chemotherapy response, and survival. DR4, DR5, and Fas were expressed by the majority of specimens, with less frequent expression of TNFR1 and TNFR2. DR4 (P = .005) and TNFR2 (P = .041) expression was higher in FIGO stage IV compared with stage III tumors. Effusions from patients who responded poorly to chemotherapy administered at disease recurrence had significantly higher DR4 (P = .006), DR5 (P = .01), and Fas (P = .001) expression. In univariate survival analysis, higher DR4 expression in viable cells correlated with poor overall (P = .0352) and progression-free (P = .0411) survival. DR4 expression was found to be an independent predictor of overall (P = .008) and progression-free (P = .003) survival. The authors have presented the first evidence of death receptor coexpression in ovarian carcinoma effusions. The association of death receptor expression in effusions with advanced stage, poor response to chemotherapy, and shorter survival suggests that these molecules are linked to an aggressive clinical course in metastatic ovarian carcinoma.
    Cancer 02/2008; 112(1):84-93. · 4.77 Impact Factor
  • Article: Low-molecular weight forms of cyclin E differentiate ovarian carcinoma from cells of mesothelial origin and are associated with poor survival in ovarian carcinoma.
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    ABSTRACT: The authors recently reported on the role of cyclin E in differentiating ovarian/primary peritoneal carcinoma from malignant peritoneal mesothelioma using gene expression arrays. In the current study, they analyzed the expression of low-molecular weight (LMW) forms of cyclin E in ovarian carcinoma, malignant mesothelioma, and benign reactive effusions. Cyclin E protein expression was analyzed in 98 effusions (72 ovarian carcinomas, 14 malignant mesotheliomas, and 12 reactive specimens) using immunoblotting. Sixty-two ovarian carcinoma effusions were studied further for cyclin E expression using immunohistochemistry. The correlations between cyclin E expression in ovarian carcinoma and clinical parameters, including chemotherapy response, were analyzed. LMW forms of cyclin E were identified in 54 of 72 ovarian carcinoma effusions (75%) compared with 1 of 14 malignant mesothelioma effusions (7%) and 1 of 12 reactive effusions (8%) (P < .001). Their presence in ovarian carcinoma was associated with a higher percentage of cyclin E-positive cells (P = .001) and increased staining intensity (P < .001) using immunohistochemistry. The presence of LMW forms of cyclin E was correlated with shorter overall survival (P = .021) and progression-free survival (P = .020). The presence of a higher percentage of cyclin E-positive cells using immunohistochemistry was correlated with shorter progression-free survival (P = .026). No association with chemotherapy response was observed. LMW forms of cyclin E differentiated ovarian carcinoma from benign and malignant mesothelial cells and were associated with increased protein expression using immunohistochemistry. The expression of LMW cyclin E forms was not associated with chemotherapy response, although it may be a marker of aggressive disease in patients with metastatic ovarian carcinoma.
    Cancer 10/2007; 110(6):1264-71. · 4.77 Impact Factor
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    Article: DNA methylation profiling of ovarian carcinomas and their in vitro models identifies HOXA9, HOXB5, SCGB3A1, and CRABP1 as novel targets.
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    ABSTRACT: The epigenetics of ovarian carcinogenesis remains poorly described. We have in the present study investigated the promoter methylation status of 13 genes in primary ovarian carcinomas (n = 52) and their in vitro models (n = 4; ES-2, OV-90, OVCAR-3, and SKOV-3) by methylation-specific polymerase chain reaction (MSP). Direct bisulphite sequencing analysis was used to confirm the methylation status of individual genes. The MSP results were compared with clinico- pathological features. Eight out of the 13 genes were hypermethylated among the ovarian carcinomas, and altogether 40 of 52 tumours were methylated in one or more genes. Promoter hypermethylation of HOXA9, RASSF1A, APC, CDH13, HOXB5, SCGB3A1 (HIN-1), CRABP1, and MLH1 was found in 51% (26/51), 49% (23/47), 24% (12/51), 20% (10/51), 12% (6/52), 10% (5/52), 4% (2/48), and 2% (1/51) of the carcinomas, respectively, whereas ADAMTS1, MGMT, NR3C1, p14ARF, and p16INK4a were unmethylated in all samples. The methylation frequencies of HOXA9 and SCGB3A1 were higher among relatively early-stage carcinomas (FIGO I-II) than among carcinomas of later stages (FIGO III-IV; P = 0.002, P = 0.020, respectively). The majority of the early-stage carcinomas were of the endometrioid histotype. Additionally, HOXA9 hypermethylation was more common in tumours from patients older than 60 years of age (15/21) than among those of younger age (11/30; P = 0.023). Finally, there was a significant difference in HOXA9 methylation frequency among the histological types (P = 0.007). DNA hypermethylation of tumour suppressor genes seems to play an important role in ovarian carcinogenesis and HOXA9, HOXB5, SCGB3A1, and CRABP1 are identified as novel hypermethylated target genes in this tumour type.
    Molecular Cancer 02/2007; 6:45. · 3.99 Impact Factor
  • Article: Nuclear expression of survivin is associated with improved survival in metastatic ovarian carcinoma.
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    ABSTRACT: Inhibitor of apoptosis proteins (IAPs) mediate cancer cell survival and chemoresistance. The expression of XIAP, Survivin, and Livin in ovarian carcinoma was analyzed. Effusions (106) were analyzed for XIAP, Survivin, and Livin expression using immunoblotting. Effusions (220), corresponding primary tumors (60), and solid metastases (103) were further immunohistochemically analyzed for XIAP and Survivin expression. The results were analyzed for association with anatomic site, clinicopathologic parameters, and survival. Immunoblotting showed frequent expression of XIAP and Survivin, and no expression of Livin. Immunohistochemistry showed cytoplasmic XIAP expression in 208 of 220 (94%) effusions, 50 of 60 (83%) primary tumors, and 87 of 103 (84%) solid metastases, with a significantly higher staining extent in effusions (P < .001). Cytoplasmic Survivin was found in 194 of 220 (88%) effusions, 55 of 60 (92%) primary tumors, and 102 of 103 (99%) solid metastases, with a significantly higher cytoplasmic staining extent in solid metastases (P = .018 and P = .006 compared with primary tumors and effusions, respectively). Nuclear Survivin was expressed in 159 of 220 (72%) effusions, 54 of 60 (90%) primary carcinomas, and 96 of 103 (93%) solid metastases (P > .05). For patients with prechemotherapy effusions, higher nuclear Survivin expression correlated with better progression-free (P = .0003) and overall (P = .002) survival in univariate survival analysis. Nuclear Survivin expression was found to be an independent predictor of progression-free survival (P = .004). XIAP and Survivin, but not Livin, are frequently expressed in ovarian carcinoma. XIAP and cytoplasmic Survivin are up-regulated in effusions and solid metastases, respectively, possibly mediating survival at these sites. Nuclear Survivin expression predicts better outcome in prechemotherapy patients.
    Cancer 02/2007; 109(2):228-38. · 4.77 Impact Factor
  • Article: DNA methylation profiling of ovarian carcinomas and their in vitro models identifies HOXA9 , HOXB5 , SCGB3A1 , and CRABP1 as novel targets
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    ABSTRACT: Abstract Background The epigenetics of ovarian carcinogenesis remains poorly described. We have in the present study investigated the promoter methylation status of 13 genes in primary ovarian carcinomas (n = 52) and their in vitro models (n = 4; ES-2, OV-90, OVCAR-3, and SKOV-3) by methylation-specific polymerase chain reaction (MSP). Direct bisulphite sequencing analysis was used to confirm the methylation status of individual genes. The MSP results were compared with clinico- pathological features. Results Eight out of the 13 genes were hypermethylated among the ovarian carcinomas, and altogether 40 of 52 tumours were methylated in one or more genes. Promoter hypermethylation of HOXA9 , RASSF1A , APC , CDH13 , HOXB5 , SCGB3A1 (HIN-1) , CRABP1 , and MLH1 was found in 51% (26/51), 49% (23/47), 24% (12/51), 20% (10/51), 12% (6/52), 10% (5/52), 4% (2/48), and 2% (1/51) of the carcinomas, respectively, whereas ADAMTS1 , MGMT , NR3C1 , p14 <sup> ARF </sup>, and p16 <sup> INK 4 a </sup>were unmethylated in all samples. The methylation frequencies of HOXA9 and SCGB3A1 were higher among relatively early-stage carcinomas (FIGO I-II) than among carcinomas of later stages (FIGO III-IV; P = 0.002, P = 0.020, respectively). The majority of the early-stage carcinomas were of the endometrioid histotype. Additionally, HOXA9 hypermethylation was more common in tumours from patients older than 60 years of age (15/21) than among those of younger age (11/30; P = 0.023). Finally, there was a significant difference in HOXA9 methylation frequency among the histological types ( P = 0.007). Conclusion DNA hypermethylation of tumour suppressor genes seems to play an important role in ovarian carcinogenesis and HOXA9 , HOXB5 , SCGB3A1 , and CRABP1 are identified as novel hypermethylated target genes in this tumour type.
    Molecular Cancer. 01/2007;
  • Article: Expression of E-cadherin transcriptional regulators in ovarian carcinoma.
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    ABSTRACT: Unlike most epithelial cancers, E-cadherin expression is upregulated in ovarian carcinoma effusions compared with corresponding primary tumors. In the present study, we analyzed the anatomic site-specific expression of transcription factors that negatively regulate E-cadherin in ovarian carcinoma. Using reverse-transcription polymerase chain reaction, mRNA in situ hybridization, and Western blotting, we analyzed the expression and localization of the Snail, Slug, and SIP1 transcription factors and E-cadherin in 78 effusions, 41 primary carcinomas, and 15 solid metastases. Slug mRNA and protein expression was highest in metastases (p=0.042 and p<0.001, respectively). Snail mRNA was comparable at all anatomic sites, but higher protein expression was found in primary tumors and solid metastases compared with effusions (p<0.001). SIP1 mRNA expression was higher in effusions (p<0.001) compared to other sites. Confocal microscopy analysis of fresh and cultured cells from effusion specimens revealed cytoplasmic localization of the Snail protein in primary tumor cells, with a nuclear shift following culturing of these cells. In conclusion, E-cadherin and its negative regulators show site-dependent expression in ovarian carcinoma. In solid tumors, E-cadherin is negatively regulated by Snail and Slug. In effusions, SIP1 may be the main regulator of E-cadherin, but with a lesser level of suppression compared with primary tumors and solid metastases.
    Archiv für Pathologische Anatomie und Physiologie und für Klinische Medicin 11/2006; 449(5):520-8. · 2.49 Impact Factor
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    Article: NK- and B-cell infiltration correlates with worse outcome in metastatic ovarian carcinoma.
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    ABSTRACT: We studied the clinical role of leukocyte infiltration and chemokine receptor expression in ovarian carcinoma effusions. Expression of leukocyte markers (CD3, CD4, CD8, CD4/CD8 ratio, CD16, CD19, and CD14) and chemokine receptors (CXCR1, CXCR4, CCR2, CCR5, and CCR7) was studied in 73 effusions by using flow cytometry. CXCR4, CCR5, and CCR7 were expressed abundantly on leukocytes, but all receptors were expressed rarely on cancer cells. The presence of natural killer cells (P = .042) and International Federation of Gynecology and Obstetrics (FIGO) stage IV disease (P = .024) predicted worse overall survival (OS). A higher percentage of CD19+ cells (P = .015) and stage IV disease (P = .008) predicted poor survival for patients with postchemotherapy effusions. Only FIGO stage retained significance as a predictor of OS (P = .035) in multivariate analysis. Chemokine receptors are expressed widely on leukocytes but rarely on carcinoma cells in ovarian carcinoma effusions, arguing against an autocrine chemokine pathway in this malignancy. Immune response parameters in ovarian cancer effusions are weak predictors of outcome.
    American Journal of Clinical Pathology 04/2006; 125(3):451-8. · 2.60 Impact Factor
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    Article: The EPH receptor Bs (EPHBs) promoters are unmethylated in colon and ovarian cancers.
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    ABSTRACT: Aberrant expression of EPH receptors and their ligands, ephrins, has been reported in a large variety of human cancers, including epithelial cancers from the colon and ovary. Due to the recently reported decrease or loss of EPHBs expression in colorectal carcinomas and the abundance of CpG sites in their promoters, we analyzed the promoter methylation status of three members of the EPHB family, EPHB2, EPHB3 and EPHB4, in a series of 22 colon cancer cell lines, as well as in four ovarian cancer cell lines and 56 ovarian tumor samples. The promoters of the three receptor genes were unmethylated in the vast majority of samples as assessed by methylation-specific polymerase chain reaction (MSP). These results were confirmed by direct bisulphite sequencing. Furthermore, from RT-PCR analyzes and Northern blotting, EPHB2 showed only small variation in RNA expression across ovarian cancer cell lines and clinical samples. We conclude that promoter hypermethylation of EPHB2, EPHB3 and EPHB4 is not a common event in colon and ovarian cancers and therefore plays no major role in these tumors.
    Epigenetics: official journal of the DNA Methylation Society 2(4):237-43. · 4.58 Impact Factor