37 results on '"Ter Haar NT"'
Search Results
2. Validation and Implementation of BRCA1/2 Variant Screening in Ovarian Tumor Tissue
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de Jonge, MM, Ruano, D, Eijk, R, van der Stoep, N, Nielsen, M, Wijnen, JT, ter Haar, NT, Baalbergen, A, Bos, Monique, Kagie, MJ, Vreeswijk, MPG, Gaarenstroom, KN, Kroep, JR, Smit, V, Bosse, T, van Wezel, T, van Asperen, CJ, de Jonge, MM, Ruano, D, Eijk, R, van der Stoep, N, Nielsen, M, Wijnen, JT, ter Haar, NT, Baalbergen, A, Bos, Monique, Kagie, MJ, Vreeswijk, MPG, Gaarenstroom, KN, Kroep, JR, Smit, V, Bosse, T, van Wezel, T, and van Asperen, CJ
- Published
- 2018
3. Loss of heterozygosity on chromosome arm 16q in breast cancer: clinical, molecular and statistical approaches
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Cleton-Jansen, A-M, primary, van Beerendonk, HM, additional, ter Haar, NT, additional, Eilers, PHC, additional, van Houwelingen, HC, additional, Bonsing, BA, additional, Smit, VTHBM, additional, van Ommen, G-JB, additional, and Cornelisse, CJ, additional
- Published
- 2000
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4. E-cadherin inactivation in lobular carcinoma in situ of the breast: an early event in tumorigenesis
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Vos, CB, primary, Cleton-Jansen, AM, additional, Berx, G, additional, de Leeuw, WJF, additional, ter Haar, NT, additional, van Roy, F, additional, Cornelisse, CJ, additional, Peterse, JL, additional, and van de Vijver, MJ, additional
- Published
- 1997
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5. Distribution of T cells and signs of T-cell activation in the rheumatoid joint: implications for semiquantitative comparative histology.
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Dolhain, RJEM, Ter Haar, NT, de Kuiper, R, Nieuwenhuis, IG, Zwinderman, AH, and Breedveld, FC
- Abstract
A prerequisite for comparative histology of synovial tissue by means of biopsies is insight into the distribution of a marker under study. This investigation focuses on the variation in the presence of T cells and signs of T-cell activation within the rheumatoid joint. For this purpose, multiple slides from several pieces of synovial tissue from different parts of a joint were stained and scored for the expression of CD3, CD25, HLA-DR, Ki67 and interferon-γ. The variation in scores for the presence of T cells and markers of activation was more pronounced in slides prepared from different pieces of tissue than in slides from one piece of tissue. Based on multiple analysis of variance, methods are suggested to establish a reliable overall score for the expression of a certain marker within a joint. Following validation, such methods may prove to be useful by allowing semiquantitative histology of synovial tissue for studies on arthritis. [ABSTRACT FROM PUBLISHER]
- Published
- 1998
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6. Performance of a RAD51-based functional HRD test on paraffin-embedded breast cancer tissue.
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van Wijk LM, Vermeulen S, Ter Haar NT, Kramer CJH, Terlouw D, Vrieling H, Cohen D, and Vreeswijk MPG
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- Humans, Female, BRCA1 Protein genetics, Homologous Recombination, Paraffin Embedding, BRCA2 Protein genetics, Rad51 Recombinase genetics, Breast Neoplasms diagnosis, Breast Neoplasms genetics, Ovarian Neoplasms genetics
- Abstract
Purpose: BRCA-deficient breast cancers (BC) are highly sensitive to platinum-based chemotherapy and PARP inhibitors due to their deficiency in the homologous recombination (HR) pathway. However, HR deficiency (HRD) extends beyond BRCA-associated BC, highlighting the need for a sensitive method to enrich for HRD tumors in an alternative way. A promising approach is the use of functional HRD tests which evaluate the HR capability of tumor cells by measuring RAD51 protein accumulation at DNA damage sites. This study aims to evaluate the performance of a functional RAD51-based HRD test for the identification of HRD BC., Methods: The functional HR status of 63 diagnostic formalin-fixed paraffin-embedded (FFPE) BC samples was determined by applying the RAD51-FFPE test. Samples were screened for the presence of (epi)genetic defects in HR and matching tumor samples were analyzed with the RECAP test, which requires ex vivo irradiated fresh tumor tissue on the premise that the HRD status as determined by the RECAP test faithfully represented the functional HR status., Results: The RAD51-FFPE test identified 23 (37%) of the tumors as HRD, including three tumors with pathogenic variants in BRCA1/2. The RAD51-FFPE test showed a sensitivity of 88% and a specificity of 76% in determining the HR-class as defined by the RECAP test., Conclusion: Given its high sensitivity and compatibility with FFPE samples, the RAD51-FFPE test holds great potential to enrich for HRD tumors, including those associated with BRCA-deficiency. This potential extends to situations where DNA-based testing may be challenging or not easily accessible in routine clinical practice. This is particularly important considering the potential implications for treatment decisions and patient stratification., (© 2023. The Author(s).)
- Published
- 2023
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7. RAD51 as a biomarker for homologous recombination deficiency in high-grade serous ovarian carcinoma: robustness and interobserver variability of the RAD51 test.
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Kramer CJ, Llop-Guevara A, Yaniz-Galende E, Pellegrino B, Ter Haar NT, Herencia-Ropero A, Campanini N, Musolino A, Bosse T, Leary A, Serra V, and Vreeswijk MP
- Subjects
- Female, Humans, Observer Variation, Reproducibility of Results, Homologous Recombination, Biomarkers, Tumor genetics, Rad51 Recombinase genetics, Ovarian Neoplasms genetics, Ovarian Neoplasms pathology
- Abstract
The RAD51 test is emerging as a promising biomarker for the assessment of functional homologous recombination deficiency (HRD). Yet, the robustness and reproducibility of the immunofluorescence-based RAD51 test, in different academic laboratories, have not been systematically investigated. Therefore, we tested the performance of the RAD51 assay in formalin-fixed paraffin-embedded (FFPE) high-grade serous ovarian carcinoma (HGSOC) samples in four European laboratories. Here, we confirm that subtle differences in staining procedures result in low variability of RAD51 and γH2AX scores. However, substantial variability in RAD51 scoring was observed in some samples, likely due to complicating technical and biological features, such as high RAD51 signal-to-noise ratio and RAD51 heterogeneity. These results support the need to identify and perform additional quality control steps and/or automating image analysis. Altogether, resolving technical issues should be a priority, as identifying tumours with functional HRD is urgently needed to guide the individual treatment of HGSOC patients. Follow-up studies are needed to define the key tissue quality requirements to assess HRD by RAD51 in FFPE tumour samples, as this test could help in guiding the individual treatment of HGSOC patients., (© 2023 The Authors. The Journal of Pathology: Clinical Research published by The Pathological Society of Great Britain and Ireland and John Wiley & Sons Ltd.)
- Published
- 2023
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8. High-Resolution Multiparameter DNA Flow Cytometry for Accurate Ploidy Assessment and the Detection and Sorting of Tumor and Stromal Subpopulations from Paraffin-Embedded Tissues.
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Corver WE and Ter Haar NT
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- Humans, Flow Cytometry methods, Vimentin genetics, Paraffin Embedding, DNA genetics, DNA analysis, Keratins genetics, Keratins analysis, Ploidies, Carcinoma
- Abstract
This article contains detailed protocols for the simultaneous flow cytometric identification of tumor cells and stromal cells and measurement of DNA content of formalin-fixed, paraffin-embedded (FFPE) tissues. The vimentin-positive stromal cell fraction can be used as an internal reference for accurate DNA content assessments of FFPE carcinoma tissues. This allows clear detection of keratin-positive tumor cells with a DNA index lower than 1.0 (near-haploidy) and of keratin-positive tumor cells with a DNA index close to 1.0 in overall DNA aneuploid samples, thus improving DNA ploidy assessment in FFPE carcinomas. Furthermore, the protocol is useful for studying molecular genetic alterations and intratumor heterogeneity in archival FFPE samples. Keratin-positive tumor cell fractions can be sorted for further molecular genetic analysis, while DNA from the sorted vimentin-positive stromal cells can serve as a reference when normal tissue of the patient is not available. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol: Multiparameter DNA content analysis of FFPE carcinomas Alternate Protocol 1: Immunocytochemistry for keratin and vimentin, and DNA labeling for blue and red excitation Alternate Protocol 2: Immunocytochemistry for keratin and vimentin, and DNA labeling for blue excitation Support Protocol: Sorting cell population from FFPE carcinomas., (© 2023 The Authors. Current Protocols published by Wiley Periodicals LLC.)
- Published
- 2023
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9. QPOLE : A Quick, Simple, and Cheap Alternative for POLE Sequencing in Endometrial Cancer by Multiplex Genotyping Quantitative Polymerase Chain Reaction.
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Van den Heerik ASVM, Ter Haar NT, Vermij L, Jobsen JJ, Brinkhuis M, Roothaan SM, Leon-Castillo A, Ortoft G, Hogdall E, Hogdall C, Van Wezel T, Lutgens LCHW, Haverkort MAD, Khattra J, McAlpine JN, Creutzberg CL, Smit VTHBM, Gilks CB, Horeweg N, and Bosse T
- Subjects
- Female, Humans, Genotype, Poly-ADP-Ribose Binding Proteins genetics, Disease-Free Survival, Polymerase Chain Reaction, Endometrial Neoplasms diagnosis, Endometrial Neoplasms genetics, Endometrial Neoplasms pathology
- Abstract
Purpose: Detection of 11 pathogenic variants in the POLE gene in endometrial cancer (EC) is critically important to identify women with a good prognosis and reduce overtreatment. Currently, POLE status is determined by DNA sequencing, which can be expensive, relatively time-consuming, and unavailable in hospitals without specialized equipment and personnel. This may hamper the implementation of POLE -testing in clinical practice. To overcome this, we developed and validated a rapid, low-cost POLE hotspot test by a quantitative polymerase chain reaction (qPCR) assay, QPOLE ., Materials and Methods: Primer and fluorescence-labeled 5'-nuclease probe sequences of the 11 established pathogenic POLE mutations were designed. Three assays, QPOLE -frequent for the most common mutations and QPOLE -rare-1 and QPOLE-rare-2 for the rare variants, were developed and optimized using DNA extracted from formalin-fixed paraffin-embedded tumor tissues. The simplicity of the design enables POLE status assessment within 4-6 hours after DNA isolation. An interlaboratory external validation study was performed to determine the practical feasibility of this assay., Results: Cutoffs for POLE wild-type, POLE -mutant, equivocal, and failed results were predefined on the basis of a subset of POLE mutants and POLE wild-types for the internal and external validation. For equivocal cases, additional DNA sequencing is recommended. Performance in 282 EC cases, of which 99 were POLE -mutated, demonstrated an overall accuracy of 98.6% (95% CI, 97.2 to 99.9), a sensitivity of 95.2% (95% CI, 90.7 to 99.8), and a specificity of 100%. After DNA sequencing of 8.8% equivocal cases, the final sensitivity and specificity were 96.0% (95% CI, 92.1 to 99.8) and 100%. External validation confirmed feasibility and accuracy., Conclusion: QPOLE is a qPCR assay that is a quick, simple, and reliable alternative for DNA sequencing. QPOLE detects all pathogenic variants in the exonuclease domain of the POLE gene. QPOLE will make low-cost POLE -testing available for all women with EC around the globe.
- Published
- 2023
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10. The RAD51-FFPE Test; Calibration of a Functional Homologous Recombination Deficiency Test on Diagnostic Endometrial and Ovarian Tumor Blocks.
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van Wijk LM, Kramer CJH, Vermeulen S, Ter Haar NT, de Jonge MM, Kroep JR, de Kroon CD, Gaarenstroom KN, Vrieling H, Bosse T, and Vreeswijk MPG
- Abstract
PARP inhibitor (PARPi) sensitivity is related to tumor-specific defects in homologous recombination (HR). Therefore, there is great clinical interest in tests that can rapidly and reliably identify HR deficiency (HRD). Functional HRD tests determine the actual HR status by using the (dis)ability to accumulate RAD51 protein at sites of DNA damage as read-out. In this study, we further improved and calibrated a previously described RAD51-based functional HRD test on 74 diagnostic formalin-fixed paraffin-embedded (FFPE) specimens (RAD51-FFPE test) from endometrial cancer (EC n = 25) and epithelial ovarian cancer (OC n = 49) patients. We established optimal parameters with regard to RAD51 foci cut-off (≥2) and HRD threshold (15%) using matched endometrial and ovarian carcinoma specimens for which HR status had been established using a RAD51-based test that required ex vivo irradiation of fresh tissue (RECAP test). The RAD51-FFPE test detected BRCA deficient tumors with 90% sensitivity and RECAP-HRD tumors with 87% sensitivity, indicating that it is an attractive alternative to DNA-based tests with the potential to be applied in routine diagnostic pathology.
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- 2021
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11. The RECAP Test Rapidly and Reliably Identifies Homologous Recombination-Deficient Ovarian Carcinomas.
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van Wijk LM, Vermeulen S, Meijers M, van Diest MF, Ter Haar NT, de Jonge MM, Solleveld-Westerink N, van Wezel T, van Gent DC, Kroep JR, Bosse T, Gaarenstroom KN, Vrieling H, and Vreeswijk MPG
- Abstract
Recent studies have shown that the efficacy of PARP inhibitors in epithelial ovarian carcinoma (EOC) is related to tumor-specific defects in homologous recombination (HR) and extends beyond BRCA1/2 deficient EOC. A robust method with which to identify HR-deficient (HRD) carcinomas is therefore of utmost clinical importance. In this study, we investigated the proficiency of a functional HR assay based on the detection of RAD51 foci, the REcombination CAPacity (RECAP) test, in identifying HRD tumors in a cohort of prospectively collected epithelial ovarian carcinomas (EOCs). Of the 39 high-grade serous ovarian carcinomas (HGSOC), the RECAP test detected 26% (10/39) to be HRD, whereas ovarian carcinomas of other histologic subtypes ( n = 10) were all HR-proficient (HRP). Of the HRD tumors that could be sequenced, 8/9 showed pathogenic BRCA1/2 variants or BRCA1 promoter hypermethylation, indicating that the RECAP test reliably identifies HRD, including but not limited to tumors related to BRCA1/2 deficiency. Furthermore, we found a trend towards better overall survival (OS) of HGSOC patients with RECAP-identified HRD tumors compared to patients with HRP tumors. This study shows that the RECAP test is an attractive alternative to DNA-based HRD tests, and further development of a clinical grade RECAP test is clearly warranted.
- Published
- 2020
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12. Frequent Homologous Recombination Deficiency in High-grade Endometrial Carcinomas.
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de Jonge MM, Auguste A, van Wijk LM, Schouten PC, Meijers M, Ter Haar NT, Smit VTHBM, Nout RA, Glaire MA, Church DN, Vrieling H, Job B, Boursin Y, de Kroon CD, Rouleau E, Leary A, Vreeswijk MPG, and Bosse T
- Subjects
- Aged, BRCA1 Protein genetics, BRCA1 Protein metabolism, BRCA2 Protein genetics, BRCA2 Protein metabolism, Comparative Genomic Hybridization, DNA Breaks, Double-Stranded drug effects, DNA Breaks, Double-Stranded radiation effects, Endometrial Neoplasms drug therapy, Endometrial Neoplasms pathology, Endometrium drug effects, Endometrium pathology, Female, High-Throughput Nucleotide Sequencing methods, Homologous Recombination drug effects, Humans, Middle Aged, Neoplasm Grading, Poly(ADP-ribose) Polymerase Inhibitors therapeutic use, Prospective Studies, Rad51 Recombinase metabolism, Endometrial Neoplasms genetics, Endometrium metabolism, Homologous Recombination genetics, Rad51 Recombinase genetics
- Abstract
Purpose: The elevated levels of somatic copy-number alterations (SCNAs) in a subset of high-risk endometrial cancers are suggestive of defects in pathways governing genome integrity. We sought to assess the prevalence of homologous recombination deficiency (HRD) in endometrial cancers and its association with histopathologic and molecular characteristics., Experimental Design: Fresh tumor tissue was prospectively collected from 36 endometrial cancers, and functional HRD was examined by the ability of replicating tumor cells to accumulate RAD51 protein at DNA double-strand breaks (RAD51 foci) induced by ionizing radiation. Genomic alterations were determined by next-generation sequencing and array comparative genomic hybridization/SNP array. The prevalence of BRCA -associated genomic scars, a surrogate marker for HRD, was determined in the The Cancer Genome Atlas (TCGA) endometrial cancer cohort., Results: Most endometrial cancers included in the final analysis ( n = 25) were of non-endometrioid (52%), grade 3 (60%) histology, and FIGO stage I (72%). HRD was observed in 24% ( n = 6) of cases and was restricted to non-endometrioid endometrial cancers (NEEC), with 46% of NEECs being HRD compared with none of the endometrioid endometrial cancers (EEC, P = 0.014). All but 1 of the HRD cases harbored either a pathogenic BRCA1 variant or high somatic copy-number (SCN) losses of HR genes. Analysis of TCGA cases supported these results, with BRCA -associated genomic scars present in up to 48% (63/132) of NEEC versus 12% (37/312) of EEC ( P < 0.001)., Conclusions: HRD occurs in endometrial cancers and is largely restricted to non-endometrioid, TP53 -mutant endometrial cancers. Evaluation of HRD may help select patients that could benefit from treatments targeting this defect, including platinum compounds and PARP inhibitors., (©2018 American Association for Cancer Research.)
- Published
- 2019
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13. Validation and Implementation of BRCA1/2 Variant Screening in Ovarian Tumor Tissue.
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de Jonge MM, Ruano D, van Eijk R, van der Stoep N, Nielsen M, Wijnen JT, Ter Haar NT, Baalbergen A, Bos MEMM, Kagie MJ, Vreeswijk MPG, Gaarenstroom KN, Kroep JR, Smit VTHBM, Bosse T, van Wezel T, and van Asperen CJ
- Subjects
- Aged, Aged, 80 and over, Cohort Studies, DNA Methylation genetics, Female, Germ-Line Mutation genetics, Humans, Loss of Heterozygosity, Middle Aged, Promoter Regions, Genetic genetics, BRCA1 Protein genetics, BRCA2 Protein genetics, Genetic Testing, Genetic Variation, Ovarian Neoplasms genetics
- Abstract
BRCA1/2 variant analysis in tumor tissue could streamline the referral of patients with epithelial ovarian, fallopian tube, or primary peritoneal cancer to genetic counselors and select patients who benefit most from targeted treatment. We investigated the sensitivity of BRCA1/2 variant analysis in formalin-fixed, paraffin-embedded tumor tissue using a combination of next-generation sequencing and copy number variant multiplex ligation-dependent probe amplification. After optimization using a training cohort of known BRCA1/2 mutation carriers, validation was performed in a prospective cohort in which screening of BRCA1/2 tumor DNA and leukocyte germline DNA was performed in parallel. BRCA1 promoter hypermethylation and pedigree analysis were also performed. In the training cohort, 45 of 46 germline BRCA1/2 variants were detected (sensitivity, 98%). In the prospective cohort (n = 62), all six germline variants were identified (sensitivity, 100%), together with five somatic BRCA1/2 variants and eight cases with BRCA1 promoter hypermethylation. In four BRCA1/2 variant-negative patients, surveillance or prophylactic management options were offered on the basis of positive family histories. We conclude that BRCA1/2 formalin-fixed, paraffin-embedded tumor tissue analysis reliably detects BRCA1/2 variants. When taking family history of BRCA1/2 variant-negative patients into account, tumor BRCA1/2 variant screening allows more efficient selection of epithelial ovarian cancer patients for genetic counseling and simultaneously selects patients who benefit most from targeted treatment., (Copyright © 2018 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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14. Genomic Characterization of Vulvar (Pre)cancers Identifies Distinct Molecular Subtypes with Prognostic Significance.
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Nooij LS, Ter Haar NT, Ruano D, Rakislova N, van Wezel T, Smit VTHBM, Trimbos BJBMZ, Ordi J, van Poelgeest MIE, and Bosse T
- Subjects
- Female, Gene Expression Profiling, Genetic Testing, High-Throughput Nucleotide Sequencing, Humans, Kaplan-Meier Estimate, Mutation, Neoplasm Grading, Papillomaviridae genetics, Papillomavirus Infections complications, Papillomavirus Infections virology, Prognosis, Vulvar Neoplasms etiology, Vulvar Neoplasms mortality, Genetic Predisposition to Disease, Genome-Wide Association Study methods, Genomics methods, Precancerous Conditions, Vulvar Neoplasms diagnosis, Vulvar Neoplasms genetics
- Abstract
Purpose: Vulvar cancer (VC) can be subclassified by human papillomavirus (HPV) status. HPV-negative VCs frequently harbor TP53 mutations; however, in-depth analysis of other potential molecular genetic alterations is lacking. We comprehensively assessed somatic mutations in a large series of vulvar (pre)cancers. Experimental Design: We performed targeted next-generation sequencing (17 genes), p53 immunohistochemistry and HPV testing on 36 VC and 82 precursors (sequencing cohort). Subsequently, the prognostic significance of the three subtypes identified in the sequencing cohort was assessed in a series of 236 VC patients (follow-up cohort). Results: Frequent recurrent mutations were identified in HPV-negative vulvar (pre)cancers in TP53 (42% and 68%), NOTCH1 (28% and 41%), and HRAS (20% and 31%). Mutation frequency in HPV-positive vulvar (pre)cancers was significantly lower ( P = 0.001). Furthermore, a substantial subset of the HPV-negative precursors (35/60, 58.3%) and VC (10/29, 34.5%) were TP53 wild-type (wt), suggesting a third, not-previously described, molecular subtype. Clinical outcomes in the three different subtypes (HPV
+ , HPV- /p53wt, HPV- /p53abn) were evaluated in a follow-up cohort consisting of 236 VC patients. Local recurrence rate was 5.3% for HPV+ , 16.3% for HPV- /p53wt and 22.6% for HPV- /p53abn tumors ( P = 0.044). HPV positivity remained an independent prognostic factor for favorable outcome in the multivariable analysis ( P = 0.020). Conclusions: HPV- and HPV+ vulvar (pre)cancers display striking differences in somatic mutation patterns. HPV- /p53wt VC appear to be a distinct clinicopathologic subgroup with frequent NOTCH1 mutations. HPV+ VC have a significantly lower local recurrence rate, independent of clinicopathological variables, opening opportunities for reducing overtreatment in VC. Clin Cancer Res; 23(22); 6781-9. ©2017 AACR ., (©2017 American Association for Cancer Research.)- Published
- 2017
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15. L1 cell adhesion molecule (L1CAM) is a strong predictor for locoregional recurrences in cervical cancer.
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Schrevel M, Corver WE, Vegter ME, Ter Haar NT, Dreef EJ, Beltman JJ, Kenter G, Bosse T, de Kroon CD, and Jordanova ES
- Abstract
Background: L1 cell adhesion molecule (L1CAM) has been shown to be a prognostic marker in various cancer types, and has been suggested to play a role in epithelial mesenchymal transition (EMT). Here, we determined the prognostic significance of L1CAM in cervical cancer and its association with vimentin expression on tumor cells, indicative of EMT., Methods: Formalin-fixed, paraffin-embedded primary tumor samples from 372 cervical cancer patients were collected for immunohistochemical analysis of L1CAM expression. In 109 FFPE specimens, the percentage of vimentin expressing tumor cells was determined by flow cytometry., Results: Positive L1CAM expression (≥10% of tumor cells) was associated with disease-free survival, validated using RNAseq TCGA data. L1CAM expression was independently associated with locoregional recurrence-free survival (hazard ratio 2.62, 95% CI 1.33 - 5.17, P = 0.006), and strongly associated with percentage of vimentin expressing tumor cells ( P = 0.003). Expression of both L1CAM and vimentin indicated a subgroup with the highest risk of recurrence (hazard ratio 3.15, 95% CI 1.25 - 7.92, P = 0.015)., Conclusion: L1CAM might be a promising new prognostic marker for locoregional recurrences in cervical cancer, and its association with vimentin expression suggests that L1CAM might affect tumor aggressiveness, possibly through EMT., Competing Interests: CONFLICTS OF INTEREST None
- Published
- 2017
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16. Incidence Changes of Human Papillomavirus in Oropharyngeal Squamous Cell Carcinoma and Effects on Survival in the Netherlands Cancer Institute, 1980-2009.
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Henneman R, Van Monsjou HS, Verhagen CV, Van Velthuysen ML, Ter Haar NT, Osse EM, Lopez-Yurda MI, Balm AJ, and Van Den Brekel MW
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- Carcinoma, Squamous Cell mortality, DNA, Viral genetics, Female, Humans, Incidence, Male, Middle Aged, Netherlands, Oropharyngeal Neoplasms mortality, Papillomavirus Infections mortality, Papillomavirus Infections virology, Risk Factors, Carcinoma, Squamous Cell etiology, Carcinoma, Squamous Cell virology, Human papillomavirus 16 genetics, Oropharyngeal Neoplasms etiology, Oropharyngeal Neoplasms virology, Papillomavirus Infections complications
- Abstract
Aim: Human papillomavirus (HPV) is a risk factor for oropharyngeal squamous cell carcinoma (OPSCC), with an increasing incidence. The present study aimed to determine the changing incidence of HPV in patients with OPSCC in the period 1980-2009 and its influence on survival., Patients and Methods: We randomly sampled 158 patients from a cohort of 828 patients with OPSCC stratified by decade (1980-1989, 1990-1999, 2000-2009). Formalin-fixed paraffin-embedded material was tested for HPV DNA by SPF-10 polymerase chain reaction (PCR) and immunohistochemically stained for p16 and p53., Results: DNA from 146 patients was suitable for HPV detection. HPV DNA was detected in 13/47 (28%), 18/47 (38%), and 20/52 (38%) patients in the cohorts of 1980-1989, 1990-1999, and 2000-2009, respectively (p-value for trend=0.269). Lack of further increase during the most recent decade is inconsistent with the rising incidence and higher prevalence reported in other Western countries. Patients with HPV-positive OPSCC had a better survival in spite of higher tumor stage., (Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)
- Published
- 2015
17. CDKN2A(p16) and HRAS are frequently mutated in vulvar squamous cell carcinoma.
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Trietsch MD, Spaans VM, ter Haar NT, Osse EM, Peters AA, Gaarenstroom KN, and Fleuren GJ
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- Aged, Carcinoma, Squamous Cell mortality, Cyclin-Dependent Kinase Inhibitor p16, Female, Humans, Neoplasm Proteins, Survival Rate, Vulvar Neoplasms mortality, Carcinoma, Squamous Cell genetics, Genes, p16, Mutation, Proto-Oncogene Proteins p21(ras) genetics, Vulvar Neoplasms genetics
- Abstract
Background: Two etiologic pathways of vulvar cancer are known, a human papillomavirus (HPV)- and a TP53-associated route, respectively, but other genetic changes may also play a role. Studies on somatic mutations in vulvar cancer other than TP53 are limited in number and size. In this study, we investigated the prevalence of genetic mutations in 107 vulvar squamous cell carcinomas (VSCCs)., Methods: A total of 107 paraffin-embedded tissue samples of primarily surgically treated VSCCs were tested for HPV infection and screened for mutations in 14 genes (BRAF, CDKN2A(p16), CTNNB1, FBXW7, FGFR2, FGFR3, FOXL2, HRAS, KRAS, NRAS, PIK3CA, PPP2R1A, PTEN, and TP53) using Sanger sequencing and mass spectrometry., Results: Mutations were detected in 7 genes. Of 107 VSCCs, 66 tumors (62%) contained at least one mutation (TP53=58, CDKN2A(p16)=14, HRAS=10, PIK3CA=7, PPP2R1A=3, KRAS=1, PTEN=1). Mutations occurred most frequently in HPV-negative samples. Five-year survival was significantly worse for patients with a mutation (47% vs 59%, P=.035), with a large effect from patients carrying HRAS-mutations., Conclusion: Somatic mutations were detected in 62% of VSCCs. As expected, HPV infection and TP53-mutations play a key role in the development of VSCC, but CDKN2A(p16), HRAS, and PIK3CA-mutations were also frequently seen in HPV-negative patients. Patients with somatic mutations, especially HRAS-mutations, have a significantly worse prognosis than patients lacking these changes, which could be of importance for the development of targeted therapy., (Copyright © 2014. Published by Elsevier Inc.)
- Published
- 2014
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18. High concordance of molecular tumor alterations between pre-operative curettage and hysterectomy specimens in patients with endometrial carcinoma.
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Stelloo E, Nout RA, Naves LC, Ter Haar NT, Creutzberg CL, Smit VT, and Bosse T
- Subjects
- Aged, Aged, 80 and over, Biomarkers, Tumor metabolism, Biopsy, Carcinoma, Endometrioid metabolism, Carcinoma, Endometrioid pathology, Carcinoma, Endometrioid surgery, Endometrial Neoplasms metabolism, Endometrial Neoplasms pathology, Endometrial Neoplasms surgery, Female, Genes, p53 genetics, Genetic Markers, Humans, Immunohistochemistry, Microsatellite Instability, Middle Aged, Mutation, PTEN Phosphohydrolase metabolism, Reproducibility of Results, beta Catenin metabolism, Biomarkers, Tumor genetics, Carcinoma, Endometrioid genetics, Curettage, DNA, Neoplasm analysis, Endometrial Neoplasms genetics, Hysterectomy, Tumor Suppressor Protein p53 metabolism
- Abstract
Objective: Molecular alterations in endometrial cancer have been shown to be prognostically significant but have not yet been implemented in the current clinical risk assessment. Few studies have investigated the reliability of molecular alterations in pre-operative specimens. Therefore, the objective was to determine whether molecular analysis of pre-operative endometrial cancer samples accurately reflects those alterations in the subsequent hysterectomy specimens., Methods: Paired pre-operative and hysterectomy specimens of 48 patients diagnosed with endometrial carcinoma, 42 endometrioid (EEC) and 6 non-endometrioid (NEEC) carcinomas, were analyzed for immunohistochemical expression of p53, PTEN and β-catenin. Tumor DNA was isolated and analyzed for microsatellite instability (MSI), TP53 mutations and somatic hot spot mutations in 13 genes., Results: In EEC patients, loss of PTEN, nuclear β-catenin and p53-mutant expression was found in 43%, 7% and 12%, respectively. No nuclear β-catenin was found in 5 of 6 NEEC patients, all serous cancers, whereas a p53-mutant expression was present in all serous cases. MSI was found in 19.5%, all EEC. Concordance for PTEN, β-catenin, p53 expression and MSI status was found in 79%, 92%, 79% and 93.5%, respectively. We detected 65 hot spot mutations in 39/48 (81%) tumors. Overall concordance of the GynCarta multigene analysis was 99.8%., Conclusions: The results confirm the reliability of immunohistochemical and DNA-based techniques in the evaluation of molecular alterations in pre-operative endometrial specimens and high concordance rates with the definitive hysterectomy specimens. The resulting molecular signature provides initial pre-operative diagnostic information on the status of oncogenic pathways, which may contribute to individualized treatment strategies., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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19. Loss of ARID1A expression and its relationship with PI3K-Akt pathway alterations, TP53 and microsatellite instability in endometrial cancer.
- Author
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Bosse T, ter Haar NT, Seeber LM, v Diest PJ, Hes FJ, Vasen HF, Nout RA, Creutzberg CL, Morreau H, and Smit VT
- Subjects
- Adaptor Proteins, Signal Transducing genetics, Adult, Aged, Aged, 80 and over, Chromosomal Proteins, Non-Histone analysis, Class I Phosphatidylinositol 3-Kinases, Colorectal Neoplasms, Hereditary Nonpolyposis enzymology, Colorectal Neoplasms, Hereditary Nonpolyposis genetics, DNA Mutational Analysis, DNA-Binding Proteins analysis, Down-Regulation, Endometrial Neoplasms pathology, Female, Gene Expression Regulation, Neoplastic, Gene Silencing, Genetic Predisposition to Disease, Humans, Immunohistochemistry, Middle Aged, MutL Protein Homolog 1, Nuclear Proteins genetics, PTEN Phosphohydrolase analysis, Phenotype, Prognosis, Promoter Regions, Genetic, Proto-Oncogene Proteins genetics, Proto-Oncogene Proteins p21(ras), SMARCB1 Protein, Signal Transduction, ras Proteins genetics, Endometrial Neoplasms enzymology, Endometrial Neoplasms genetics, Microsatellite Instability, Mutation, Nuclear Proteins analysis, Phosphatidylinositol 3-Kinases genetics, Proto-Oncogene Proteins c-akt analysis, Transcription Factors analysis, Tumor Suppressor Protein p53 analysis
- Abstract
The switch/sucrose non-fermentable (SWI/SNF) subunit ARID1A (AT-rich interactive domain 1A gene) has been recently postulated as a novel tumor suppressor of gynecologic cancer and one of the driver genes in endometrial carcinogenesis. However, specific relationships with established molecular alterations in endometrioid endometrial cancer (EEC) are currently unknown. We analyzed the expression of ARID1A in 146 endometrial cancers (130 EECs and 16 non-EECs) in relation to alterations in the PI3K-Akt pathway (PTEN expression/KRAS/PIK3CA mutations), TP53 status (TP53 immunohistochemistry) and microsatellite instability. To discriminate between microsatellite instability due to somatic MLH1 promoter hypermethylation or germline mutations in one of the mismatch repair genes (Lynch syndrome), we included a 'Lynch syndrome set'. This set included 21 cases with confirmed germline mutations and 15 cases that were suspected to have a germline mutation. Loss of ARID1A expression was exclusively found in EECs in 31% (40/130) of the EEC cases. No loss of expression of the other subunits of the SWI/SNF complex, SMARCD3 and SMARCB1, was detected. Alterations in the PI3K-Akt pathway were more frequent when ARID1A expression was lost. Loss of ARID1A and mutant-like TP53 expression was nearly mutually exclusive (P=0.0004). In contrast to Lynch-associated tumors, a strong association between ARID1A loss and sporadic microsatellite instability was found. Only five cases (14%) of the 'Lynch syndrome set' as compared with 24 cases (75%, P<0.0001) of the sporadic microsatellite-unstable tumors showed loss of ARID1A. These observations suggest that ARID1A is a causative gene, instead of a target gene, of microsatellite instability by having a role in epigenetic silencing of the MLH1 gene in endometrial cancer.
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- 2013
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20. Spindle cell morphology is related to poor prognosis in vulvar squamous cell carcinoma.
- Author
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Trietsch MD, Peters AA, Gaarenstroom KN, van Koningsbrugge SH, ter Haar NT, Osse EM, Halbesma N, and Fleuren GJ
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- Aged, Cohort Studies, Female, Humans, Multivariate Analysis, Neoplasm Staging, Prognosis, Retrospective Studies, Carcinoma, Squamous Cell pathology, Vulvar Neoplasms pathology
- Abstract
Background: Vulvar cancer is the fourth most common gynaecological malignancy, with an annual incidence of 2 out of 100,000 women. Although most cases of early stage vulvar cancer have a good prognosis, recurrence and rapid tumour progression can occur. We investigated the prevalence of spindle cell morphology in vulvar cancer and its association with survival., Methods: This retrospective cohort study included 108 patients with primary vulvar squamous cell carcinoma who were treated at the Leiden University Medical Center during 2000-2009. Paraffin-embedded tissue was examined for the presence of spindle cell morphology. Survival and histology data were compared between cases with spindle and without spindle cell morphology., Results: Twenty-two (20%) tumours showed spindle cells infiltrating the stromal tissue. All spindle cell tumours were human papillomavirus (HPV) negative. Spindle cell morphology was strongly associated with poor prognosis and with a high risk of lymph node involvement at the time of diagnosis (relative risk 2.26 (95% CI 1.47-3.47)). Five-year disease-specific survival was lower in patients with vs without spindle cell morphology (45.2% vs 79.7%, respectively; P=0.00057)., Conclusion: Vulvar spindle cell morphology occurs frequently and seems to develop through the non-HPV pathway. It is associated with a worse prognosis than conventional vulvar squamous cell carcinoma.
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- 2013
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21. Loss of heterozygosity and copy number alterations in flow-sorted bulky cervical cancer.
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van den Tillaart SA, Corver WE, Ruano Neto D, ter Haar NT, Goeman JJ, Trimbos JB, Fleuren GJ, and Oosting J
- Subjects
- Adult, Aged, Aged, 80 and over, Chromosome Aberrations, Female, Flow Cytometry, Humans, Middle Aged, Polymorphism, Single Nucleotide, Uterine Cervical Neoplasms pathology, DNA Copy Number Variations, Loss of Heterozygosity, Uterine Cervical Neoplasms genetics
- Abstract
Treatment choices for cervical cancer are primarily based on clinical FIGO stage and the post-operative evaluation of prognostic parameters including tumor diameter, parametrial and lymph node involvement, vaso-invasion, infiltration depth, and histological type. The aim of this study was to evaluate genomic changes in bulky cervical tumors and their relation to clinical parameters, using single nucleotide polymorphism (SNP)-analysis. Flow-sorted tumor cells and patient-matched normal cells were extracted from 81 bulky cervical tumors. DNA-index (DI) measurement and whole genome SNP-analysis were performed. Data were analyzed to detect copy number alterations (CNA) and allelic balance state: balanced, imbalanced or pure LOH, and their relation to clinical parameters. The DI varied from 0.92-2.56. Pure LOH was found in ≥40% of samples on chromosome-arms 3p, 4p, 6p, 6q, and 11q, CN gains in >20% on 1q, 3q, 5p, 8q, and 20q, and losses on 2q, 3p, 4p, 11q, and 13q. Over 40% showed gain on 3q. The only significant differences were found between histological types (squamous, adeno and adenosquamous) in the lesser allele intensity ratio (LAIR) (p = 0.035) and in the CNA analysis (p = 0.011). More losses were found on chromosome-arm 2q (FDR = 0.004) in squamous tumors and more gains on 7p, 7q, and 9p in adenosquamous tumors (FDR = 0.006, FDR = 0.004, and FDR = 0.029). Whole genome analysis of bulky cervical cancer shows widespread changes in allelic balance and CN. The overall genetic changes and CNA on specific chromosome-arms differed between histological types. No relation was found with the clinical parameters that currently dictate treatment choice.
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- 2013
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22. Multiparameter DNA content analysis identifies distinct groups in primary breast cancer.
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Dayal JH, Sales MJ, Corver WE, Purdie CA, Jordan LB, Quinlan PR, Baker L, ter Haar NT, Pratt NR, and Thompson AM
- Subjects
- Adult, Aged, Aged, 80 and over, Breast Neoplasms classification, Breast Neoplasms mortality, Female, Genes, p53, Humans, Middle Aged, Mutation, Prognosis, Receptor, ErbB-2 analysis, Receptors, Progesterone metabolism, Breast Neoplasms genetics, DNA, Neoplasm analysis, Flow Cytometry methods
- Abstract
Background: Multiparameter flow cytometry is a robust and reliable method for determining tumour DNA content applicable to formalin-fixed paraffin-embedded (FFPE) tissue. This study examined the clinical and pathological associations of DNA content in primary breast cancer using an improved multiparametric technique., Methods: The FFPE tissue from 201 primary breast cancers was examined and the cancers categorised according to their DNA content using multiparametric flow cytometry incorporating differential labelling of stromal and tumour cell populations. Mathematical modelling software (ModFit 3.2.1) was used to calculate the DNA index (DI) and percentage S-phase fraction (SPF%) for each tumour. Independent associations with clinical and pathological parameters were sought using backward stepwise Binary Logistic Regression (BLR) and Cox's Regression (CR) analysis., Results: Tumours were grouped into four categories based on the DI of the tumour cell population. Low DI tumours (DI=0.76-1.14) associated with progesterone receptor-positive status (P=0.012, BLR), intermediate DI (DI=1.18-1.79) associated with p53 mutant tumours (P=0.001, BLR), high DI (DI1.80) tumours with human epidermal growth factor receptor 2 (HER2)-positive status (P=0.004, BLR) and 'multiploid tumours' (two or more tumour DNA peaks) did not show any significant associations. Tumours with high SPF% (10%) independently associated with poor overall survival (P=0.027, CR)., Conclusion: Multiparametric flow analysis of FFPE tissue can accurately assess tumour DNA content. Tumour sub-populations associated with biomarkers of prognosis or likely response to therapy. The alterations in DNA content present the potential for greater understanding of the mechanisms underlying clinically significant biomarker changes in primary breast cancer.
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- 2013
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23. Improved risk assessment of endometrial cancer by combined analysis of MSI, PI3K-AKT, Wnt/β-catenin and P53 pathway activation.
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Nout RA, Bosse T, Creutzberg CL, Jürgenliemk-Schulz IM, Jobsen JJ, Lutgens LC, van der Steen-Banasik EM, van Eijk R, Ter Haar NT, and Smit VT
- Subjects
- Adaptor Proteins, Signal Transducing genetics, Adaptor Proteins, Signal Transducing metabolism, Aged, Aged, 80 and over, Disease-Free Survival, Exons, Female, Humans, Kaplan-Meier Estimate, Methylation, Middle Aged, Multivariate Analysis, MutL Protein Homolog 1, Mutation, Nuclear Proteins genetics, Nuclear Proteins metabolism, PTEN Phosphohydrolase metabolism, Promoter Regions, Genetic, Proportional Hazards Models, Proto-Oncogene Proteins genetics, Proto-Oncogene Proteins c-akt metabolism, Proto-Oncogene Proteins p21(ras), Risk Assessment, Sequence Analysis, DNA, Transcription Factors genetics, Transcription Factors metabolism, Tumor Suppressor Protein p53 metabolism, beta Catenin metabolism, ras Proteins genetics, Endometrial Neoplasms genetics, Endometrial Neoplasms metabolism, Microsatellite Instability, Neoplasm Recurrence, Local metabolism, Tumor Suppressor Protein p53 genetics, Wnt Signaling Pathway genetics
- Abstract
Objective: To investigate if analysis of genetic alterations in the main pathways involved in endometrioid type carcinogenesis (PI3K-AKT, Wnt/β-catenin, P53-activation and MSI) improves the current risk assessment based on clinicopathological factors., Methods: Formalin fixed paraffin embedded (FFPE) primary tumor samples of 65 patients with FIGO-stage I endometrioid type endometrial cancer (EEC) were selected from the randomized PORTEC-2 trial. Tumors were stained by immunohistochemistry for P53, PTEN and β-catenin. Tumor DNA was isolated for sequence analysis of TP53 (exons 4 to 8), hotspot mutation analysis of KRAS (exon 1) and PI3K (exon 9 and 20) and microsatellite-instability (MSI) analysis including MLH1 promotor-methylation status. Univariate and multivariate analyses for disease-free survival (DFS) using Cox regression models were performed., Results: P53 status (HR 6.7, 95%CI 1.75-26.0, p=0.006) and MSI were the strongest single genetic prognostic factors for decreased DFS, while high PI3K-AKT pathway activation showed a trend and β-catenin was not prognostic. The combination of multiple activated pathways was the most powerful prognostic factor for decreased DFS (HR 5.0; 95%CI 1.59-15.6 p=0.006). Multiple pathway activation, found in 8% of patients, was strongly associated with aggressive clinical course. In contrast, 40% of patients had no alterations in the investigated pathways and had a very low risk of disease progression., Conclusions: Activation of multiple oncogenic pathways in EEC was the most powerful prognostic factor for decreased DFS, resulting in an individual risk assessment superior to the current approach based on clinicopathological factors., (Copyright © 2012 Elsevier Inc. All rights reserved.)
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- 2012
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24. CXCR7 expression is associated with disease-free and disease-specific survival in cervical cancer patients.
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Schrevel M, Karim R, ter Haar NT, van der Burg SH, Trimbos JB, Fleuren GJ, Gorter A, and Jordanova ES
- Subjects
- Adenocarcinoma pathology, Adult, Aged, Aged, 80 and over, Carcinoma, Squamous Cell pathology, Cervix Uteri metabolism, Cervix Uteri pathology, Chemokine CXCL12 metabolism, ErbB Receptors metabolism, Female, Humans, Immunoenzyme Techniques, Lymphatic Metastasis, Middle Aged, Prognosis, Receptors, CXCR4 metabolism, Survival Rate, Uterine Cervical Neoplasms pathology, Young Adult, Adenocarcinoma metabolism, Adenocarcinoma mortality, Carcinoma, Squamous Cell metabolism, Carcinoma, Squamous Cell mortality, Receptors, CXCR metabolism, Uterine Cervical Neoplasms metabolism, Uterine Cervical Neoplasms mortality
- Abstract
Background: The CXC chemokine receptor (CXCR)7 is involved in tumour development and metastases formation. The aim of the present study was to determine protein expression of CXCR7, its putative co-receptors epidermal growth factor receptor (EGFR) and CXCR4, its predominant ligand CXCL12, their co-dependency and their association with survival in cervical cancer patients., Methods: CXC chemokine receptor 7, EGFR, CXCR4 and CXCL12 expression were determined immunohistochemically in 103 paraffin-embedded, cervical cancers. Subsequently, associations with patient characteristics were assessed and survival analyses were performed., Results: CXC chemokine receptor 7 was expressed by 43% of tumour specimens, in a large majority of cases together with either EGFR or CXCR4 (double positive), or both (triple positive). The CXCR7 expression was associated with tumour size (P=0.013), lymph node metastasis (P=0.001) and EGFR expression (P=0.009). CXC chemokine receptor 7 was independently associated with disease-free survival (hazard ratio (HR)=4.3, 95% confidence intervals (CI) 1.7-11.0, P=0.002), and strongly associated with disease-specific survival (HR=3.9, 95% CI 1.5-10.2, P=0.005)., Conclusion: CXC chemokine receptor 7 expression predicts poor disease-free and disease-specific survival in cervical cancer patients, and might be a promising new therapeutic marker. In a large majority of cases, CXCR7 is co-expressed with CXCR4 and/or EGFR, supporting the hypothesis that these receptors assist in CXCR7 signal transduction.
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- 2012
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25. Cervical carcinoma-associated fibroblasts are DNA diploid and do not show evidence for somatic genetic alterations.
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Corver WE, Ter Haar NT, Fleuren GJ, and Oosting J
- Subjects
- Female, Flow Cytometry, Humans, Immunohistochemistry, In Vitro Techniques, Microsatellite Repeats genetics, Mutation, Polymorphism, Single Nucleotide genetics, Vimentin genetics, DNA genetics, Diploidy, Fibroblasts metabolism, Uterine Cervical Neoplasms genetics
- Abstract
Background: Cancer-associated fibroblasts (CAFs) have been recognized as important contributors to cancer development and progression. However, opposing evidence has been published whether CAFs, in addition to epigenetic, also undergo somatic genetic alterations and whether these changes contribute to carcinogenesis and tumour progression., Methods: We combined multiparameter DNA flow cytometry, flow-sorting and 6K SNP-arrays to study DNA aneuploidy, % S-phase, loss of heterozygosity (LOH) and copy number alterations (CNAs) in cervical cancer-associated stromal cell fractions (n = 57) from formalin-fixed, paraffin-embedded (FFPE) samples. Tissue sections were examined for the presence of CAFs. Microsatellite analysis was used to confirm LOH findings., Results: Smooth muscle actin and vimentin immunohistochemistry verified the presence of CAFs in all cases tested. However, we found no evidence for DNA aneuploidy, somatic genetic alterations in the vimentin-positive stromal cell fractions of any samples, while high frequencies of DNA content abnormalities (43/57) and substantial numbers of CNAs and LOH were identified in the keratin-positive epithelial cell fractions. LOH hot-spots on chromosomes 3p, 4p and 6p found were confirmed by microsatellite analysis., Conclusion: From our study we conclude that stromal cell fractions from cervical carcinomas are DNA diploid, have a genotype undistinguishable from patient-matched normal tissue and are genetically stable. Using flow cytometry and SNP-arrays, stromal genetic changes do not seem to play a role during cervical carcinogenesis and progression. In addition, the stromal cell fraction of cervical carcinomas can be used as reference allowing large retrospective studies of archival FFPE tissues for which no normal reference tissue is available.
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- 2011
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26. High-resolution multiparameter DNA flow cytometry for the detection and sorting of tumor and stromal subpopulations from paraffin-embedded tissues.
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Corver WE and Ter Haar NT
- Subjects
- Cell Separation, DNA, Neoplasm analysis, Humans, Keratins, Methods, Ploidies, Vimentin, DNA analysis, Flow Cytometry methods, Neoplasms pathology, Paraffin Embedding, Stromal Cells cytology
- Abstract
This unit contains a detailed protocol for the simultaneous flow cytometric measurement of tumor cells, stromal cells, and DNA content of formalin-fixed, paraffin-embedded (FFPE) tissues. The vimentin-positive stromal cell fraction can be used as an internal reference for DNA content assessments. This allows clear detection of keratin-positive tumor cells with a DNA index lower than 1.0 and of keratin-positive tumor cells with a DNA close to 1.0 in overall DNA aneuploid samples, thus improved DNA ploidy assessment in FFPE carcinomas. Furthermore, the protocol is useful for studying molecular genetic alterations and intratumor heterogeneity in archival FFPE samples. Keratin-positive tumor cell fractions can be flow-sorted for further molecular genetic analysis, while DNA from the sorted vimentin-positive stromal cells can serve as a reference when normal tissue of the patient is not available., (© 2010 by John Wiley & Sons, Inc.)
- Published
- 2011
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27. High-resolution multiparameter DNA flow cytometry for the detection and sorting of tumor and stromal subpopulations from paraffin-embedded tissues.
- Author
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Corver WE and ter Haar NT
- Subjects
- Humans, Keratins chemistry, Molecular Biology, Paraffin Embedding, Ploidies, Tissue Fixation methods, Vimentin chemistry, Cell Separation methods, DNA, Neoplasm analysis, Flow Cytometry methods, Neoplasms diagnosis, Neoplasms pathology
- Abstract
This unit contains a detailed protocol for the simultaneous flow cytometric measurement of tumor cells, stromal cells, and DNA content of formalin-fixed, paraffin-embedded (FFPE) tissues. The vimentin-positive stromal cell fraction can be used as an internal reference for DNA content assessments. This allows clear detection of keratin-positive tumor cells with a DNA index lower than 1.0 and of keratin-positive tumor cells with a DNA close to 1.0 in overall DNA aneuploid samples, thus improved DNA ploidy assessment in FFPE carcinomas. Furthermore, the protocol is useful for studying molecular genetic alterations and intratumor heterogeneity in archival FFPE samples. Keratin-positive tumor cell fractions can be flow-sorted for further molecular genetic analysis, while DNA from the sorted vimentin-positive stromal cells can serve as a reference when normal tissue of the patient is not available.
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- 2009
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28. Genome-wide allelic state analysis on flow-sorted tumor fractions provides an accurate measure of chromosomal aberrations.
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Corver WE, Middeldorp A, ter Haar NT, Jordanova ES, van Puijenbroek M, van Eijk R, Cornelisse CJ, Fleuren GJ, Morreau H, Oosting J, and van Wezel T
- Subjects
- Alleles, Allelic Imbalance, DNA, Neoplasm genetics, Female, Flow Cytometry, Gene Amplification, Humans, In Situ Hybridization, Fluorescence, Loss of Heterozygosity, Polymorphism, Single Nucleotide, Chromosome Aberrations, Colonic Neoplasms genetics, Uterine Cervical Neoplasms genetics
- Abstract
Chromosomal aberrations are a common characteristic of cancer and are associated with copy number abnormalities and loss of heterozygosity (LOH). Tumor heterogeneity, low tumor cell percentage, and lack of knowledge of the DNA content impair the identification of these alterations especially in aneuploid tumors. To accurately detect allelic changes in carcinomas, we combined flow-sorting and single nucleotide polymorphism arrays. Cells derived from archival cervical and colon cancers were flow-sorted based on differential vimentin and keratin expression and DNA content and analyzed on single nucleotide polymorphism arrays. A new algorithm, the lesser allele intensity ratio, was used to generate a molecular measure of chromosomal aberrations for each case. Flow-sorting significantly improved the detection of copy number abnormalities; 31.8% showed an increase in amplitude and 23.2% were missed in the unsorted fraction, whereas 15.9% were detected but interpreted differently. Integration of the DNA index in the analysis enabled the identification of the allelic state of chromosomal aberrations, such as LOH ([A]), copy-neutral LOH ([AA]), balanced amplifications ([AABB]), and allelic imbalances ([AAB] or [AAAB], etc.). Chromosomal segments were sharply defined. Fluorescence in situ hybridization copy numbers, as well as the high similarity between the DNA index and the allelic state index, which is the average of the allelic states across the genome, validated the method. This new approach provides an individual molecular measure of chromosomal aberrations and will likely have repercussions for preoperative molecular staging, classification, and prognostic profiling of tumors, particularly for heterogeneous aneuploid tumors, and allows the study of the underlying molecular genetic mechanisms and clonal evolution of tumor subpopulations.
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- 2008
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29. Expression and genetic analysis of transporter associated with antigen processing in cervical carcinoma.
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Vermeulen CF, Jordanova ES, ter Haar NT, Kolkman-Uljee SM, de Miranda NF, Ferrone S, Peters AA, and Fleuren GJ
- Subjects
- ATP-Binding Cassette Transporters biosynthesis, ATP-Binding Cassette Transporters immunology, DNA Mutational Analysis, Female, Flow Cytometry, Histocompatibility Antigens Class I biosynthesis, Histocompatibility Antigens Class I genetics, Histocompatibility Antigens Class I immunology, Humans, Immunohistochemistry, Loss of Heterozygosity, Neoplasm Staging, Paraffin Embedding, Uterine Cervical Neoplasms pathology, Uterine Cervical Dysplasia pathology, ATP-Binding Cassette Transporters genetics, Uterine Cervical Neoplasms genetics, Uterine Cervical Neoplasms immunology, Uterine Cervical Dysplasia genetics, Uterine Cervical Dysplasia immunology
- Abstract
Objective: Transporter associated with antigen processing (TAP) loss causes human leukocyte antigen (HLA) class I downregulation which is frequently found in cervical carcinomas and their precursors. HLA class I molecules activate T-cells by antigen presentation and are therefore essential for immunological surveillance. To add to the hitherto limited knowledge of molecular mechanisms underlying TAP loss, we investigated TAP expression, loss of heterozygosity (LOH) and possible TAP mutations., Methods: Twenty-three cervical carcinomas and adjacent precursor lesions were stained with HLA-A-, HLA-B/C-, beta2 -microglobulin-, TAP1- and TAP2- antibodies. In order to separate tumour and non-tumour cells, cervical carcinoma samples were sorted by flow-cytometry and were subsequently analysed for LOH with 3 markers in the TAP region on chromosome 6p21.3. Mutation analysis of the complete TAP1 gene was performed., Results: Aberrant TAP1 expression was detected in 10/23 cervical carcinoma lesions and in 5/10 adjacent cervical intraepithelial neoplasia (CIN) lesions. All the lesions with low TAP expression also had reduced HLA class I expression. LOH was found in 7 out of 10 lesions with TAP loss. Mutation analysis detected no aberrations, but identified a polymorphism in the 5'-untranslated region (UTR) of the TAP1 gene in two lesions., Conclusions: This study shows that defective TAP expression in cervical carcinoma is often associated with LOH in the TAP region but not with mutations in the TAP1 gene.
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- 2007
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30. Frequent HLA class I loss is an early event in cervical carcinogenesis.
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Vermeulen CF, Jordanova ES, Zomerdijk-Nooijen YA, ter Haar NT, Peters AA, and Fleuren GJ
- Subjects
- Carcinoma, Squamous Cell genetics, Carcinoma, Squamous Cell pathology, Chromosomes, Human, Pair 6 genetics, Female, Humans, In Situ Hybridization, Fluorescence, Time Factors, Uterine Cervical Neoplasms genetics, Uterine Cervical Neoplasms pathology, Uterine Cervical Dysplasia genetics, Uterine Cervical Dysplasia pathology, Carcinoma, Squamous Cell immunology, HLA Antigens genetics, HLA Antigens metabolism, Histocompatibility Antigens Class I genetics, Histocompatibility Antigens Class I metabolism, Loss of Heterozygosity immunology, Uterine Cervical Neoplasms immunology, Uterine Cervical Dysplasia immunology
- Abstract
Loss at chromosome 6p21.3, the human leukocyte antigen (HLA) region, is the main cause of HLA downregulation, occurring in the majority of invasive cervical carcinomas. To identify the stage of tumor development at which HLA class I aberrations occur, we selected 12 patients with cervical carcinoma and adjacent cervical intraepithelial neoplasia (CIN). We investigated HLA class I and beta2-microglobulin expression by immunohistochemistry in tumor and adjacent CIN. Loss of heterozygosity (LOH) was studied using microsatellite markers covering the HLA region. Fluorescent in situ hybridization with HLA class I probes was performed to investigate the mechanism of HLA loss. Immunohistochemistry showed absent or weak HLA class I expression in 11/12 cases. In 10 of these 11 cases, downregulation occurred in both tumor and CIN. Only in one case did the concomitant CIN lesion show normal expression. In 9/12 cases, LOH was present for at least one marker in both tumor and CIN, 1 case showed only LOH in the CIN lesion, and 1 case showed retention of heterozygosity for all markers in both tumor and CIN. We conclude that HLA class I aberrations occur early and frequently in cervical carcinogenesis. This might allow premalignant CIN lesions to escape immune surveillance and progress to invasive cancer.
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- 2005
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31. High-resolution multi-parameter DNA flow cytometry enables detection of tumour and stromal cell subpopulations in paraffin-embedded tissues.
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Corver WE, Ter Haar NT, Dreef EJ, Miranda NF, Prins FA, Jordanova ES, Cornelisse CJ, and Fleuren GJ
- Subjects
- Antibodies, Monoclonal immunology, Colorectal Neoplasms chemistry, Colorectal Neoplasms pathology, Female, Flow Cytometry methods, Formaldehyde, Hot Temperature, Humans, Keratins analysis, Keratins immunology, Loss of Heterozygosity, Neoplasm Proteins analysis, Neoplasm Proteins immunology, Paraffin Embedding, Ploidies, Tissue Fixation methods, Uterine Cervical Neoplasms chemistry, Uterine Cervical Neoplasms pathology, Vimentin analysis, Vimentin immunology, Colorectal Neoplasms genetics, DNA, Neoplasm analysis, Stromal Cells pathology, Uterine Cervical Neoplasms genetics
- Abstract
The accuracy of DNA ploidy measurements of paraffin-embedded tissues is limited by the lack of resolution and the inability to identify the DNA diploid population unequivocally in bimodal DNA histograms. A multi-parameter DNA flow cytometric method has been developed that enables the simultaneous detection of neoplastic and stromal cells in samples from dewaxed 50 microm sections or 2 mm diameter punches of archival tissue blocks. The method combines heat pretreatment in sodium citrate buffer and subsequent enzymatic dissociation with a collagenase/dispase mixture. Cells were simultaneously stained for keratin (FITC), vimentin (R-PE), and DNA (PI) before flow cytometric analysis. The method was applied to 12 paraffin-embedded cervical carcinomas and four colorectal carcinomas. In all cervical cancers, distinct keratin-positive and vimentin-positive cell populations were observed. While the exclusive vimentin-positive cell fractions always yielded unimodal DNA content distributions, bimodal distributions were observed for the keratin-positive cell fractions in nine cervical carcinomas, whereas one cervical carcinoma showed three distinct G0G1 populations. Coefficients of variation of the G0G1 peaks ranged from 1.70% to 4.79%. Average background, aggregate, and debris values were 14.7% (vimentin-positive fraction) and 33.8% (keratin-positive fraction). Flow sorting confirmed that the exclusively vimentin-positive cell fractions represent different normal stromal and infiltrate cells that can serve as an internal ploidy reference enabling discrimination between DNA hypo-diploid and DNA hyper-diploid tumour cell subpopulations. The neoplastic origin of the keratin-vimentin co-expressing cells from two cervical carcinomas was confirmed by genotyping of flow-sorted samples revealing loss of heterozygosity (LOH) of 6p. This improved method obviates the need for fresh/frozen tumour tissue for high-resolution DNA ploidy measurements and enables the isolation of highly purified tumour subpopulations for subsequent genotyping., (Copyright 2005 Pathological Society of Great Britain and Ireland)
- Published
- 2005
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32. PCR artifacts in LOH and MSI analysis of microdissected tumor cells.
- Author
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Sieben NL, ter Haar NT, Cornelisse CJ, Fleuren GJ, and Cleton-Jansen AM
- Subjects
- Alleles, Artifacts, Breast Neoplasms genetics, Breast Neoplasms pathology, Carcinoma genetics, Carcinoma pathology, Colorectal Neoplasms genetics, Colorectal Neoplasms pathology, Dissection, Female, Humans, Lymphoma, B-Cell, Marginal Zone genetics, Lymphoma, B-Cell, Marginal Zone pathology, Micromanipulation, Neoplasms genetics, Neoplasms pathology, Polymerase Chain Reaction, Reproducibility of Results, Stomach Neoplasms genetics, Stomach Neoplasms pathology, DNA, Neoplasm analysis, Loss of Heterozygosity, Microsatellite Repeats
- Abstract
Polymerase chain reaction (PCR) analysis to study loss of heterozygosity (LOH) and microsatellite instability (MSI) in tumors is widely used. Microdissection techniques are applied to obtain tumor-specific tissue cells. By microdissection, however, the amount of template DNA extracted may vary considerably and interfere with optimal PCR amplification. To circumvent LOH and MSI misinterpretations due to low DNA input, we have assessed the critical level of DNA input for reliable PCR analysis. PCR analysis was performed by using 18 polymorphic markers (mono-, di-, tri-, and tetranucleotide) on DNA derived from both paraffin-embedded, formalin-fixed, and fresh frozen tumor specimens at template input levels ranging from 0.05 to 25.0 ng. We show a highly significant relation between DNA input and the occurrence of LOH and MSI artifacts. Furthermore, for DNA extracted from paraffin-embedded material, the percentage of LOH artifacts is significantly higher compared with DNA extracted from frozen tissue. For reliable PCR analyses using a mono-, di-, tri-, or tetranucleotide marker, a minimum of 10.0 ng DNA is required when DNA is isolated from formalin-fixed, paraffin-embedded tissue and 5.0 ng when isolated from fresh frozen tissue. HUM PATHOL 31:1414-1419., (Copyright 2000 by W.B. Saunders Company)
- Published
- 2000
33. Genetic alterations on chromosome 16 and 17 are important features of ductal carcinoma in situ of the breast and are associated with histologic type.
- Author
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Vos CB, ter Haar NT, Rosenberg C, Peterse JL, Cleton-Jansen AM, Cornelisse CJ, and van de Vijver MJ
- Subjects
- Alleles, Blotting, Southern, Breast Neoplasms pathology, Carcinoma, Intraductal, Noninfiltrating pathology, Female, Filaggrin Proteins, Genetic Markers, Humans, Loss of Heterozygosity, Microsatellite Repeats, Nucleic Acid Hybridization, Breast Neoplasms genetics, Carcinoma, Intraductal, Noninfiltrating genetics, Chromosomes, Human, Pair 16, Chromosomes, Human, Pair 17
- Abstract
We analysed the involvement of known and putative tumour suppressor- and oncogene loci in ductal carcinoma in situ (DCIS) by microsatellite analysis (LOH), Southern blotting and comparative genomic hybridization (CGH). A total of 78 pure DCIS cases, classified histologically as well, intermediately and poorly differentiated, were examined for LOH with 76 markers dispersed along all chromosome arms. LOH on chromosome 17 was more frequent in poorly differentiated DCIS (70%) Compared to well-differentiated DCIS (17%), whereas loss on chromosome 16 was associated with well- and intermediately differentiated DCIS (66%). For a subset we have done Southern blot-and CGH analysis. C-erbB2/neu was amplified in 30% of poorly differentiated DCIS. No amplification was found of c-myc, mdm2, bek, flg and the epidermal growth factor (EGF)-receptor. By CGH, most frequent alterations in poorly differentiated DCIS were gains on 8q and 17q22-24 and deletion on 17p, whereas in well-differentiated DCIS amplification on chromosome 1q and deletion on 16q were found. In conclusion, our data indicates that inactivation of a yet unknown tumour suppressor gene on chromosome 16q is implicated in the development of most well and intermediately differentiated DCIS whereas amplification and inactivation of various genes on chromosome 17 are implicated in the development of poorly differentiated DCIS. Furthermore these data show that there is a genetic basis for the classification of DCIS in a well and poorly differentiated type and support the evidence of different genetic routes to develop a specific type of carcinoma in situ of the breast.
- Published
- 1999
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34. Cyclin D1 gene amplification and overexpression are present in ductal carcinoma in situ of the breast.
- Author
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Vos CB, Ter Haar NT, Peterse JL, Cornelisse CJ, and van de Vijver MJ
- Subjects
- Blotting, Southern, Breast Neoplasms metabolism, Carcinoma in Situ metabolism, Carcinoma, Ductal, Breast metabolism, Female, Gene Expression, Humans, Immunoenzyme Techniques, In Situ Hybridization, Neoplasm Proteins metabolism, Receptors, Estrogen metabolism, Breast Neoplasms genetics, Carcinoma in Situ genetics, Carcinoma, Ductal, Breast genetics, Cyclin D1 metabolism, Genes, bcl-1
- Abstract
Cyclin D1 (CCND1) amplification is found in 10-15 per cent of invasive breast carcinomas, but it is not well established whether this gene alteration also occurs in the precursor of invasive breast carcinoma, ductal carcinoma in situ (DCIS). By Southern blot analysis, cyclin D1 gene amplification was detected in 10 per cent (3/32) of DCIS cases. In addition, 15 cases of DCIS were analysed using bright field in situ hybridization (BRISH), of which 11 had already been analysed by Southern blotting. One additional case with gene amplification was found by BRISH. The use of BRISH for the detection of gene amplification is shown to be a novel and reliable in situ method on paraffin-embedded tissue sections. By immunohistochemistry, 147 cases of DCIS were analysed for the expression of cyclin D1. Cyclin D1 overexpression was found in 9 per cent of well-differentiated, 29 per cent of intermediately differentiated, and 19 per cent of poorly differentiated DCIS. No statistically significant association was found between cyclin D1 overexpression and the differentiation grade of DCIS, although 90 per cent of the cases that show overexpression are classified as intermediately and poorly differentiated. An association was found between cyclin D1 overexpression and oestrogen receptor positivity. Cyclin D1 overexpression was found in all four cases with cyclin D1 gene amplification, but was also found in 30 per cent (8/27) of cases without detectable gene amplification. It is concluded that cyclin D1 gene amplification is an early event in the development of breast carcinoma and occurs in poorly differentiated DCIS. Cyclin D1 protein overexpression is also present in tumours without cyclin D1 gene amplification and is seen predominantly in DCIS of intermediately and poorly differentiated histological type and oestrogen receptor positivity.
- Published
- 1999
- Full Text
- View/download PDF
35. Shift toward T lymphocytes with a T helper 1 cytokine-secretion profile in the joints of patients with rheumatoid arthritis.
- Author
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Dolhain RJ, van der Heiden AN, ter Haar NT, Breedveld FC, and Miltenburg AM
- Subjects
- Arthritis, Rheumatoid blood, CD3 Complex genetics, CD4 Antigens genetics, Humans, Interferon-gamma metabolism, Interleukin-2 metabolism, Interleukin-4 metabolism, Leukocytes, Mononuclear metabolism, Monocytes metabolism, Phenotype, Synovial Fluid cytology, Synovial Fluid metabolism, Arthritis, Rheumatoid pathology, Cytokines metabolism, Th1 Cells metabolism, Th2 Cells metabolism
- Abstract
Objective: To investigate whether T cells in the inflamed joints of patients with rheumatoid arthritis (RA) preferentially produce the T helper 1 (Th1) cytokines, interferon-gamma (IFN gamma) and interleukin-2 (IL-2), or the Th2 cytokine, IL-4, when compared with corresponding peripheral blood-derived T cells., Methods: Synovial fluid mononuclear cells (SFMC) and corresponding peripheral blood mononuclear cells (PBMC) from 10 patients with RA were analyzed, either directly or after in vitro stimulation, for the intracellular presence of Th1 and Th2 cytokines. The amount of secreted cytokine in the cell culture supernatants was measured by enzyme-linked immunosorbent assay (ELISA)., Results: IFN gamma-containing cells were detected in the unstimulated SFMC, but not in the PBMC, of 3 patients with RA. Cells positive for IL-2 or IL-4 were not detected in the unstimulated samples. Following stimulation, the mean percentage of cells containing Th1 cytokines was significantly increased in the SFMC compared with the PBMC; no differences were found in the mean percentage of IL-4-containing cells. A comparable shift toward Th1 cytokines was observed when the amount of secreted cytokine was determined by ELISA., Conclusion: A shift toward T cells with a Th1 cytokine profile was observed in the joints of patients with RA. Since an imbalance between Th1 and Th2 cells is thought to be of pathogenic significance, this finding might have implications for the development of new therapies for RA.
- Published
- 1996
- Full Text
- View/download PDF
36. Increased expression of interferon (IFN)-gamma together with IFN-gamma receptor in the rheumatoid synovial membrane compared with synovium of patients with osteoarthritis.
- Author
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Dolhain RJ, ter Haar NT, Hoefakker S, Tak PP, de Ley M, Claassen E, Breedveld FC, and Miltenburg AM
- Subjects
- Arthritis, Rheumatoid immunology, CD3 Complex analysis, Female, Humans, Hypersensitivity, Delayed immunology, Hypersensitivity, Delayed metabolism, Male, Osteoarthritis immunology, Synovial Membrane immunology, Tonsillitis immunology, Tonsillitis metabolism, Interferon gamma Receptor, Antigens, CD metabolism, Arthritis, Rheumatoid metabolism, Interferon-gamma metabolism, Osteoarthritis metabolism, Receptors, Interferon metabolism, Synovial Membrane metabolism
- Abstract
Data concerning the presence of T-cell-derived cytokines in the rheumatic joint are conflicting, challenging the hypothesis that rheumatoid arthritis (RA) is a T-cell-mediated disease. In this study synovial tissue specimens of 11 patients with RA and eight patients with osteoarthritis (OA) were stained for interferon-gamma (IFN-gamma) and its receptor. The level of expression of IFN-gamma was compared with that in tissue specimens of delayed-type hypersensitivity (DTH) reactions of the skin and of chronic tonsillitis. Furthermore, the percentage of T-lymphocytes which stained positive for IFN-gamma was determined using double staining techniques. IFN-gamma and its receptor were detected in all patients with RA and in 7/8 and 3/8, respectively, of patients with OA. Expression of IFN-gamma (P<0.02) and IFN-gamma receptor (P<0.01) in synovial tissue of patients with RA was more abundant compared with that in patients with OA. Although IFN-gamma could be detected in RA synovial tissue, the level of expression was less when compared with DTH reactions of the skin and tonsillitis. The percentage of CD3+ cells being positive for IFN-gamma was approximately 1% in RA, whereas in DTH reactions of the skin it was >90% and in tonsillitis approximately 30%. We conclude that the presence of IFN-gamma and its receptor in RA synovial tissue suggests a role for this cytokine in the ongoing immunological reaction of the inflamed joint.
- Published
- 1996
- Full Text
- View/download PDF
37. Detection of intracellular interferon-gamma by light microscopy using an immunoperoxidase technique: correlation with the corresponding mRNA and protein product.
- Author
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Dolhain RJ, Andersson U, ter Haar NT, Brinkman BM, Verweij CL, Daha MR, Breedveld FC, and Miltenburg AM
- Subjects
- Cytokines genetics, Fluorescent Antibody Technique, Granulocyte-Macrophage Colony-Stimulating Factor metabolism, Humans, Immunoenzyme Techniques, Interferon-gamma genetics, Interleukin-1 metabolism, Interleukin-2 metabolism, Interleukin-3 metabolism, Interleukin-4 metabolism, Interleukin-6 metabolism, Interleukin-8 metabolism, Polymerase Chain Reaction, Staining and Labeling, Tumor Necrosis Factor-alpha metabolism, Interferon-gamma analysis, RNA, Messenger analysis, Receptors, Interleukin-1 antagonists & inhibitors, T-Lymphocytes chemistry
- Abstract
Identifying individual cytokine-producing cells may help to acquire insight into immunological processes. This study was designed to adapt a technique for the detection of individual cytokine-producing cells from an immunofluorescence to an immunoperoxidase staining procedure. The production of interferon-gamma (IFN-gamma) by anti-CD3-activated cloned human T cells was used as a model system. After the conditions for the staining procedure were optimized, the immunoperoxidase technique was slightly more sensitive than the immunofluorescence technique. The intracellular staining for IFN-gamma was preceded or paralleled by IFN-gamma mRNA production and followed by accumulation of IFN-gamma in the supernatant. It is concluded that intracellular IFN-gamma can easily be detected using an immunoperoxidase procedure. This procedure is highly sensitive and allows quantification of the production of multiple cytokines by counting the percentage of positively staining cells.
- Published
- 1993
- Full Text
- View/download PDF
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