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Featured researches published by Harry Hollema.


The Lancet | 2000

Risk and prognosis of endometrial cancer after tamoxifen for breast cancer

L. Bergman; Maureen Lr Beelen; Maarten P.W. Gallee; Harry Hollema; J. Benraadt; Flora E. van Leeuwen

BACKGROUND Tamoxifen increases the risk of endometrial cancer. However, few studies have produced reliable risk estimates by duration, dose, and recency of use, or addressed the prognosis of endometrial cancers in tamoxifen-treated women. METHODS We did a nationwide case-control study on the risk and prognosis of endometrial cancer after tamoxifen use for breast cancer. Information on tamoxifen use and other risk factors for endometrial cancer was obtained from 309 women with endometrial cancer after breast cancer (cases), and 860 matched controls with breast cancer but without endometrial cancer. For 276 cases, we obtained tissue blocks of endometrial cancer to review the diagnosis, and used immunohistochemistry to examine hormone-receptor status and overexpression of p53. FINDINGS Tamoxifen had been used by 108 (36.1%) of 299 cases and 245 (28.5%) controls (relative risk 1.5 [95% CI 1.1-2.0]). Risk of endometrial cancer increased with longer duration of tamoxifen use (p < 0.001), with relative risks of 2.0 (1.2-3.2) for 2-5 years and 6.9 (2.4-19.4) for at least 5 years compared with non-users. Endometrial cancers of stage III and IV occurred more frequently in long-term tamoxifen users (> or = 2 years) than in non-users (17.4% vs 5.4%, p=0.006). Long-term users were more likely than non-users to have had malignant mixed mesodermal tumours or sarcomas of the endometrium (15.4% vs 2.9%, p < or = 0.02), p53-positive tumours (31.4% vs 18.2%, p=0.05), and negative oestrogen-receptor concentrations (60.8% vs 26.2%, p < or = 0.001). 3-year endometrial-cancer-specific survival was significantly worse for long-term tamoxifen users than for non-users (76% for > or = 5 years, 85% for 2-5 years vs 94% for non-users, p=0.02). INTERPRETATION Long-term tamoxifen users have a worse prognosis of endometrial cancers, which seems to be due to less favourable histology and higher stage. However, the benefit of tamoxifen on breast-cancer survival far outweighs the increased mortality from endometrial cancer. Nevertheless, we seriously question widespread use of tamoxifen as a preventive agent against breast cancer in healthy women.


American Journal of Human Genetics | 1999

Association of hereditary nonpolyposis colorectal cancer-related tumors displaying low microsatellite instability with MSH6 germline mutations

Ying Wu; Maran J.W. Berends; Rob G.J. Mensink; Claudia Kempinga; Rolf H. Sijmons; Ate G.J. van der Zee; Harry Hollema; Jan H. Kleibeuker; Charles H.C.M. Buys; Robert M. W. Hofstra

Hereditary nonpolyposis colorectal cancer (HNPCC) (Amsterdam criteria) is often caused by mutations in mismatch repair (MMR) genes, and tumors of patients with HNPCC show microsatellite instability (MSI-high phenotype). Germline mutations of MMR genes have rarely been found in families that have HNPCC or suspected HNPCC and that do not show microsatellite instability (MSI-low phenotype). Therefore, an MSI-high phenotype is often used as an inclusion criterion for mutation testing of MMR genes. Correction of base-base mismatches is the major function of MSH6. Since mismatches present with an MSI-low phenotype, we assumed that the phenotype in patients with HNPCC-related tumors might be associated with MSH6 germline mutations. We divided 36 patients with suspected HNPCC into an MSI-low group (n=18) and an MSI-high group (n=18), on the basis of the results of MSI testing. Additionally, three unrelated patients from Amsterdam families with MSI-low tumors were investigated. All patients were screened for MSH2, MLH1, and MSH6 mutations. Four presumably causative MSH6 mutations were detected in the patients (22%) who had suspected HNPCC and MSI-low tumors. Furthermore, we detected one frameshift mutation in one of the three patients with HNPCC and MSI-low tumors. In the MSI-high group, one MSH6 missense mutation was found, but the same patient also had an MLH1 mutation, which may explain the MSI-high phenotype. These results suggest that MSH6 may be involved in a substantial proportion of patients with HNPCC or suspected HNPCC and MSI-low tumors. Our data emphasize that an MSI-low phenotype cannot be considered an exclusion criterion for mutation testing of MMR genes in general.


American Journal of Human Genetics | 2002

Molecular and Clinical Characteristics of MSH6 Variants: An Analysis of 25 Index Carriers of a Germline Variant

Maran J.W. Berends; Ying Wu; Rolf H. Sijmons; Rob G.J. Mensink; Tineke van der Sluis; Jannet M. Hordijk-Hos; Elisabeth G.E. de Vries; Harry Hollema; Arend Karrenbeld; Charles H.C.M. Buys; Ate G.J. van der Zee; Robert M. W. Hofstra; Jan H. Kleibeuker

The MSH6 gene is one of the mismatch-repair genes involved in hereditary nonpolyposis colorectal cancer (HNPCC). Three hundred sixteen individuals who were known or suspected to have HNPCC were analyzed for MSH6 germline mutations. For 25 index patients and 8 relatives with MSH6 variants, molecular and clinical features are described. For analysis of microsatellite instability (MSI), the five consensus markers were used. Immunohistochemical analysis of the MLH1, MSH2, and MSH6 proteins was performed. Five truncating MSH6 mutations, of which one was detected seven times, were found in 12 index patients, and 10 MSH6 variants with unknown pathogenicity were found in 13 index patients. Fourteen (54%) of 26 colorectal cancers (CRCs) and endometrial cancers showed no, or only weak, MSI. Twelve of 18 tumors of truncating-mutation carriers and 3 of 17 tumors of missense-mutation carriers showed loss of MSH6 staining. Six of the families that we studied fulfilled the original Amsterdam criteria; most families with MSH6, however, were only suspected to have HNPCC. In families that did not fulfill the revised Amsterdam criteria, the prevalence of MSH6 variants is about the same as the prevalence of those in MLH1/MSH2. Endometrial cancer and/or atypical hyperplasia were diagnosed in 8 of 12 female carriers of MSH6 truncating mutations. Most CRCs were localized distally in the colon. Although, molecularly, missense variants are labeled as doubtfully pathogenic, clinical data disclose a great resemblance between missense-variant carriers and truncating-mutation carriers. We conclude that, in all patients suspected to have HNPCC, MSH6-mutation analysis should be considered. Neither MSI nor immunohistochemistry should be a definitive selection criterion for MSH6-mutation analysis.


Cancer Immunology, Immunotherapy | 2009

Prognostic significance of tumor-infiltrating T-lymphocytes in primary and metastatic lesions of advanced stage ovarian cancer

Ninke Leffers; Marloes Gooden; Renske A. de Jong; Baukje-Nynke Hoogeboom; Klaske A. ten Hoor; Harry Hollema; H. Marieke Boezen; Ate G.J. van der Zee; Toos Daemen; Hans W. Nijman

PurposeOvarian cancer patients with intra-tumoral CD3+ T-lymphocytes in primary tumor tissue have a better prognosis. This study aims to analyze the presence and relative influence of three important T-lymphocyte subsets, tumor-infiltrating CD8+ cytotoxic T-lymphocytes (CTL), CD45R0+ memory T-lymphocytes, and FoxP3+ regulatory T-lymphocytes (Treg), in primary tumor tissue and omental metastases of patients with ovarian cancer.Experimental designThe number of CD8+, CD45R0+, and FoxP3+ T-lymphocytes was determined by immunohistochemistry on a tissue micro array containing ovarian tumor tissue and/or omental metastases obtained at primary debulking surgery from 306 FIGO stage I–IV ovarian cancer patients. Immunohistochemistry data were correlated to clinicopathological parameters and survival data.ResultsHigh number of CD8+ CTL and a high CD8+/FoxP3+ ratio in ovarian-derived tumor tissue were associated with increased disease-specific survival and proved to be independent prognostic factors in multivariate analyses. In advanced stage patients, the presence of CD8+ CTL, CD45R0+ memory T-lymphocytes, FoxP3+ Treg or a high CD8+/FoxP3+ ratio in ovarian-derived tumor tissue was associated with an increased disease specific survival in univariate analysis, as was the presence of CD45R0+ memory T-lymphocytes and FoxP3+ Treg in omental metastases. Furthermore, in advanced stage patients CD8+ cytotoxic and FoxP3+ regulatory T-lymphocytes infiltrating ovarian-derived tumor tissue were independent predictors of increased prognosis.ConclusionsT-lymphocytes infiltrating primary and metastatic ovarian cancer sites are associated with improved prognosis. These associations are especially distinct in advanced stage patients, underlining the potential for immunotherapy as a broadly applicable therapeutic strategy.


The Journal of Nuclear Medicine | 2007

In Vivo VEGF Imaging with Radiolabeled Bevacizumab in a Human Ovarian Tumor Xenograft

Wouter B. Nagengast; Elisabeth G.E. de Vries; Geke A.P. Hospers; Nanno H. Mulder; Johan R. de Jong; Harry Hollema; Adrienne H. Brouwers; Guus A.M.S. van Dongen; Lars R. Perk; Marjolijn N. Lub-de Hooge

Vascular endothelial growth factor (VEGF), released by tumor cells, is an important growth factor in tumor angiogenesis. The humanized monoclonal antibody bevacizumab blocks VEGF-induced tumor angiogenesis by binding, thereby neutralizing VEGF. Our aim was to develop radiolabeled bevacizumab for noninvasive in vivo VEGF visualization and quantification with the single γ-emitting isotope 111In and the PET isotope 89Zr. Methods: Labeling, stability, and binding studies were performed. Nude mice with a human SKOV-3 ovarian tumor xenograft were injected with 89Zr-bevacizumab, 111In-bevacizumab, or human 89Zr-IgG. Human 89Zr-IgG served as an aspecific control antibody. Small-animal PET and microCT studies were obtained at 24, 72, and 168 h after injection of 89Zr-bevacizumab and 89Zr-IgG (3.5 ± 0.5 MBq, 100 ± 6 μg, 0.2 mL [mean ± SD]). Small-animal PET and microCT images were fused to calculate tumor uptake and compared with ex vivo biodistribution at 168 h after injection. 89Zr- and 111In-bevacizumab ex vivo biodistribution was compared at 24, 72, and 168 h after injection (2.0 ± 0.5 MBq each, 100 ± 4 μg in total, 0.2 mL). Results: Labeling efficiencies, radiochemical purity, stability, and binding properties were optimal for the radioimmunoconjugates. Small-animal PET showed uptake in well-perfused organs at 24 h and clear tumor localization from 72 h onward. Tumor uptake determined by quantification of small-animal PET images was higher for 89Zr-bevacizumab—namely, 7.38 ± 2.06 %ID/g compared with 3.39 ± 1.16 %ID/g (percentage injected dose per gram) for human 89Zr-IgG (P = 0.011) at 168 h and equivalent to ex vivo biodistribution studies. Tracer uptake in other organs was seen primarily in liver and spleen. 89Zr- and 111In-bevacizumab biodistribution was comparable. Conclusion: Radiolabeled bevacizumab showed higher uptake compared with radiolabeled human IgG in a human SKOV-3 ovarian tumor xenograft. Noninvasive quantitative small-animal PET was similar to invasive ex vivo biodistribution. Radiolabeled bevacizumab is a new tracer for noninvasive in vivo imaging of VEGF in the tumor microenvironment.


Journal of Clinical Oncology | 2000

Soft tissue leiomyosarcomas and malignant gastrointestinal stromal tumors: Differences in clinical outcome and expression of multidrug resistance proteins

Boudewijn E.C. Plaat; Harry Hollema; Willemina M. Molenaar; Gerben H. Torn Broers; Justin Pijpe; Mirjam F. Mastik; Harald J. Hoekstra; Eva van den Berg; Rik J. Scheper; Winette T. A. van der Graaf

PURPOSE Several studies have reported clinical behavior and chemotherapy resistance in leiomyosarcomas, but these studies did not differentiate between soft tissue leiomyosarcomas (LMS) and malignant gastrointestinal stromal tumors (GIST). Multidrug resistance (MDR) has been associated with the expression of P-glycoprotein (P-gp), multidrug resistance protein (MRP(1)), and lung resistance protein (LRP). The aim of the present study was to compare LMS and GIST with respect to clinical outcome and MDR parameters. PATIENTS AND METHODS Clinical outcome was evaluated in 29 patients with a primary deep-seated LMS and 26 patients with a primary malignant GIST. Paraffin-embedded material, available for 26 patients with LMS and 25 with GIST, was used for immunohistochemical detection of P-gp, MRP(1), LRP, and c-kit. RESULTS Mean overall survival (OS) was 72 months for LMS patients and 31 months for GIST patients (P: <.05). Metastases occurred in 16 (59%) of 27 assessable LMS patients and in 10 (56%) of 18 assessable GIST patients. LMS predominantly metastasized to the lungs (14 of 16 patients), whereas GIST tended to spread to the liver (five of 10 patients) and the abdominal cavity (three of 10 patients; P: <.001). P-gp and MRP(1) expression was more pronounced in GIST than in LMS (P: <.05): the mean percentage of P-gp expressing cells was 13.4% in patients with LMS and 38.4% in patients with GIST, and the mean percentage MRP(1) expressing cells was 13.3% in patients with LMS and 35.4% in patients with GIST. LRP expression did not differ between LMS and GIST. c-kit was expressed in 5% of the LMS patients and in 68% of the GIST patients. CONCLUSION LMS patients have a better survival than GIST patients, and the metastatic pattern is different. Expression of MDR proteins in LMS is less pronounced than in GIST.


Cancer | 2002

Vulvar carcinoma. The price of less radical surgery.

Joanne A. de Hullu; Harry Hollema; Sietske Lolkema; Marike Boezen; H. Boonstra; Matthe P. M. Burger; Jan G. Aalders; Marian J.E. Mourits; Ate G.J. van der Zee

The objective of this study was to determine whether modifications in the treatment of patients with vulvar carcinoma influence the rates of recurrence and survival.


Obstetrics & Gynecology | 2001

Tamoxifen treatment and gynecologic side effects : A review

Marian J.E. Mourits; Elisabeth G.E. de Vries; Pax H.B. Willemse; Klaske A. ten Hoor; Harry Hollema; Ate G.J. van der Zee

Objective To review the literature on tamoxifen side effects on the female genital tract and psychosexual function in premenopausal and postmenopausal women. Data Sources We used the English-language literature in MEDLINE and reference lists from selected articles. Search terms included: “tamoxifen and estrogen receptor,” “transcription activation,” “premenopause,” “postmenopause,” “vaginal epithelium,” “uterus,” “endometrial hyperplasia,” “polyps,” “endometrial cancer,” “sonography,” “sonohysterography,” “hysteroscopy,” “myometrium,” “myoma,” “sarcoma,” “endometriosis,” “ovarian cysts,” “hot flushes,” “concentration problems,” “sleep disturbance,” “vaginal dryness,” “sexual function,” “libido,” “dyspareunia,” and “quality of life.” No study-type restrictions were imposed. Methods of Study Selection With respect to clinical studies we included case cohort studies, observational studies; if no trials were available on a subject, case reports published in peer-reviewed journals were selected. For the discussion on endometrial surveillance of tamoxifen users, letters and editorials published in peer-reviewed journals also were used. Subjects of interest were mechanism of action of tamoxifen, tamoxifen and the vaginal epithelium, endometrium, mesenchymal tumors of the uterus, ovaries, sexual function, and vasomotor instability. Tabulation, Integration, and Results Eligible studies were analyzed to determine their usefulness in this review. Data from trials that evaluated tamoxifen side effects on specific genital tissues were combined, with special interest in differentiation of side effects in premenopausal and postmenopausal women. Weighted estimates of severity and extent of side effects were usually not possible because of lack of randomized trials. Only the risk of endometrial cancer in relation to tamoxifen treatment could be estimated. Conclusion The gynecologic side effects of tamoxifen are diverse and reflect the complexity of its mechanism of action, with agonistic and antagonistic effects on various tissues, depending on the ambient estradiol concentration and hence menopausal status of the patient. The most frequently reported side effect was hot flushes, and the most worrisome gynecologic side effect was a two- to three-fold increased risk of endometrial cancer in postmenopausal women. Despite its side effects, the benefits of tamoxifen in controlling breast cancer or prevention of its relapse are still without debate.


BMC Cancer | 2009

Expression of miR-21 and its targets (PTEN, PDCD4, TM1) in flat epithelial atypia of the breast in relation to ductal carcinoma in situ and invasive carcinoma

Liqiang Qi; Joost Bart; Lu Ping Tan; Inge Platteel; Tineke van der Sluis; Sippie Huitema; Geert Harms; Li Fu; Harry Hollema; Anke van den Berg

BackgroundFlat epithelial atypia (FEA) of the breast is characterised by a few layers of mildly atypical luminal epithelial cells. Genetic changes found in ductal carcinoma in situ (DCIS) and invasive ductal breast cancer (IDC) are also found in FEA, albeit at a lower concentration. So far, miRNA expression changes associated with invasive breast cancer, like miR-21, have not been studied in FEA.MethodsWe performed miRNA in-situ hybridization (ISH) on 15 cases with simultaneous presence of normal breast tissue, FEA and/or DCIS and 17 additional cases with IDC. Expression of the miR-21 targets PDCD4, TM1 and PTEN was investigated by immunohistochemistry.ResultsTwo out of fifteen cases showed positive staining for miR-21 in normal breast ductal epithelium, seven out of fifteen cases were positive in the FEA component and nine out of twelve cases were positive in the DCIS component. A positive staining of miR-21 was observed in 15 of 17 IDC cases. In 12 cases all three components were present in one tissue block and an increase of miR-21 from normal breast to FEA and to DCIS was observed in five cases. In three cases the FEA component was negative, whereas the DCIS component was positive for miR-21. In three other cases, normal, FEA and DCIS components were negative for miR-21 and in the last case all three components were positive. Overall we observed a gradual increase in percentage of miR-21 positive cases from normal, to FEA, DCIS and IDC. Immunohistochemical staining for PTEN revealed no obvious changes in staining intensities in normal, FEA, DCIS and IDC. Cytoplasmic staining of PDCD4 increased from normal to IDC, whereas, the nuclear staining decreased. TM1 staining decreased from positive in normal breast to negative in most DCIS and IDC cases. In FEA, the staining pattern for TM1 was similar to normal breast tissue.ConclusionUpregulation of miR-21 from normal ductal epithelial cells of the breast to FEA, DCIS and IDC parallels morphologically defined carcinogenesis. No clear relation was observed between the staining pattern of miR-21 and its previously reported target genes.


Nature Genetics | 2001

A role for MLH3 in hereditary nonpolyposis colorectal cancer.

Ying Wu; Maran J.W. Berends; Rolf H. Sijmons; Rob G.J. Mensink; E Verlind; Krista Kooi; Tineke van der Sluis; Claudia Kempinga; Ate G.J. van der Zee; Harry Hollema; Charles H.C.M. Buys; Jan H. Kleibeuker; Robert M. W. Hofstra

We investigated a possible role of the mismatch-repair gene MLH3 in hereditary nonpolyposis colorectal cancer by scanning for mutations in 39 HNPCC families and in 288 patients suspected of having HNPCC. We identified ten different germline MLH3 variants, one frameshift and nine missense mutations, in 12 patients suspected of HNPCC. Three of the 12 also carried a mutation in MSH6.

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Ate G.J. van der Zee

University Medical Center Groningen

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Elisabeth G.E. de Vries

University Medical Center Groningen

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Marian J.E. Mourits

University Medical Center Groningen

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Jan H. Kleibeuker

University Medical Center Groningen

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Hans W. Nijman

University Medical Center Groningen

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Klaske A. ten Hoor

University Medical Center Groningen

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Geertruida H. de Bock

University Medical Center Groningen

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Robert M. W. Hofstra

University Medical Center Groningen

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Steven de Jong

University Medical Center Groningen

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Rolf H. Sijmons

University Medical Center Groningen

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