Loes F.S. Kooreman
Maastricht University
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Publication
Featured researches published by Loes F.S. Kooreman.
The Journal of Pathology | 2018
Gonda Fj Konings; Karlijn Mc Cornel; Sofia Xanthoulea; Bert Delvoux; Margaretha A. Skowron; Loes F.S. Kooreman; Pasi Koskimies; Camilla Krakstad; Helga B. Salvesen; Kim van Kuijk; Yannick Schrooders; Marc Vooijs; Arjan J. Groot; Marlies Y. Bongers; Roy F.P.M. Kruitwagen; Andrea Romano; Enitec
The enzyme type 1 17β‐hydroxysteroid dehydrogenase (17β‐HSD‐1), responsible for generating active 17β‐estradiol (E2) from low‐active estrone (E1), is overexpressed in endometrial cancer (EC), thus implicating an increased intra‐tissue generation of E2 in this estrogen‐dependent condition. In this study, we explored the possibility of inhibiting 17β‐HSD‐1 and impairing the generation of E2 from E1 in EC using in vitro, in vivo, and ex vivo models. We generated EC cell lines derived from the well‐differentiated endometrial adenocarcinoma Ishikawa cell line and expressing levels of 17β‐HSD‐1 similar to human tissues. In these cells, HPLC analysis showed that 17β‐HSD‐1 activity could be blocked by a specific 17β‐HSD‐1 inhibitor. In vitro, E1 administration elicited colony formation similar to E2, and this was impaired by 17β‐HSD‐1 inhibition. In vivo, tumors grafted on the chicken chorioallantoic membrane (CAM) demonstrated that E1 upregulated the expression of the estrogen responsive cyclin A similar to E2, which was impaired by 17β‐HSD‐1 inhibition. Neither in vitro nor in vivo effects of E1 were observed using 17β‐HSD‐1‐negative cells (negative control). Using a patient cohort of 52 primary ECs, we demonstrated the presence of 17β‐HSD‐1 enzyme activity (ex vivo in tumor tissues, as measured by HPLC), which was inhibited by over 90% in more than 45% of ECs using the 17β‐HSD‐1 inhibitor. Since drug treatment is generally indicated for metastatic/recurrent and not primary tumor, we next demonstrated the mRNA expression of the potential drug target, 17β‐HSD‐1, in metastatic lesions using a second cohort of 37 EC patients. In conclusion, 17β‐HSD‐1 inhibition efficiently blocks the generation of E2 from E1 using various EC models. Further preclinical investigations and 17β‐HSD‐1 inhibitor development to make candidate compounds suitable for the first human studies are awaited. Copyright
Human Pathology | 2017
Margot M. Koeneman; Freyja H.M. van Lint; Sander M. J. van Kuijk; Luc Smits; Loes F.S. Kooreman; Roy F.P.M. Kruitwagen; Arnold J. Kruse
This study aims to develop a prediction model for spontaneous regression of cervical intraepithelial neoplasia grade 2 (CIN 2) lesions based on simple clinicopathological parameters. The study was conducted at Maastricht University Medical Center, the Netherlands. The prediction model was developed in a retrospective cohort of 129 women with a histologic diagnosis of CIN 2 who were managed by watchful waiting for 6 to 24months. Five potential predictors for spontaneous regression were selected based on the literature and expert opinion and were analyzed in a multivariable logistic regression model, followed by backward stepwise deletion based on the Wald test. The prediction model was internally validated by the bootstrapping method. Discriminative capacity and accuracy were tested by assessing the area under the receiver operating characteristic curve (AUC) and a calibration plot. Disease regression within 24months was seen in 91 (71%) of 129 patients. A prediction model was developed including the following variables: smoking, Papanicolaou test outcome before the CIN 2 diagnosis, concomitant CIN 1 diagnosis in the same biopsy, and more than 1 biopsy containing CIN 2. Not smoking, Papanicolaou class <3, concomitant CIN 1, and no more than 1 biopsy containing CIN 2 were predictive of disease regression. The AUC was 69.2% (95% confidence interval, 58.5%-79.9%), indicating a moderate discriminative ability of the model. The calibration plot indicated good calibration of the predicted probabilities. This prediction model for spontaneous regression of CIN 2 may aid physicians in the personalized management of these lesions.
BMC Cancer | 2017
Margot M. Koeneman; Arnold-Jan Kruse; Loes F.S. Kooreman; A. zur Hausen; Anton H. N. Hopman; Simone J. S. Sep; T Van Gorp; B. F. M. Slangen; H. J. van Beekhuizen; A. J. M. van de Sande; C. G. Gerestein; Hans W. Nijman; Roy F.P.M. Kruitwagen
AbstractThe “TOPical Imiquimod treatment of high-grade Cervical intraepithelial neoplasia” (TOPIC) trial was stopped preliminary, due to lagging inclusions. This study aimed to evaluate the treatment efficacy and clinical applicability of imiquimod 5% cream in high-grade cervical intraepithelial neoplasia (CIN). The lagging inclusions were mainly due to a strong patient preference for either of the two treatment modalities. This prompted us to initiate a new study on the same subject, with a non-randomized, open-label design: the ‘TOPical Imiquimod treatment of high-grade Cervical intraepithelial neoplasia (TOPIC)-3’ study. Original TOPIC-trial: Medical Ethics Committee approval number METC13231; ClinicalTrials.gov Identifier: NCT02329171, 22 December 2014.TOPIC-3 study: Medical Ethics Committee approval number METC162025; ClinicalTrials.gov Identifier: NCT02917746, 16 September 2016.
Breast Cancer Research | 2018
B. Goorts; Kelly M. A. Dreuning; Janneke B. Houwers; Loes F.S. Kooreman; Evert-Jan G. Boerma; Ritse M. Mann; Marc Lobbes; Marjolein L. Smidt
BackgroundThe main purpose was to investigate the correlation between magnetic resonance imaging (MRI)-based response patterns halfway through neoadjuvant chemotherapy and immunotherapy (NAC) and pathological tumor response in patients with breast cancer. Secondary purposes were to compare the predictive value of MRI-based response patterns measured halfway through NAC and after NAC and to measure interobserver variability.MethodsAll consecutive patients treated with NAC for primary invasive breast cancer from 2012 to 2015 and who underwent breast MRI before, halfway through (and after) NAC were included. All breast tumors were reassessed on MRI by two experienced breast radiologists and classified into six patterns: type 0 (complete radiologic response); type 1 (concentric shrinkage); type 2 (crumbling); type 3 (diffuse enhancement); type 4 (stable disease); type 5 (progressive disease). Percentages of tumors showing pathological complete response (pCR), > 50% tumor reduction and > 50% tumor diameter reduction per MRI-based response pattern were calculated. Correlation between MRI-based response patterns and pathological tumor reduction was studied with Pearson’s correlation coefficient, and interobserver agreement was tested with Cohen’s Kappa.ResultsPatients (n = 76; mean age 53, range 29–72 years) with 80 tumors (4 bilateral) were included. There was significant correlation between these MRI-based response patterns halfway through NAC and tumor reduction on pathology assessment (reader 1 r = 0.33; p = 0.003 and reader 2 r = 0.45; p < 0.001). Type-0, type-1 or type-2 patterns halfway through NAC showed highest tumor reduction rates on pathology assessment, with > 50% tumor reduction in 90%, 78% and 65% of cases, respectively. In 83% of tumors with type 0 halfway through NAC, pathology assessment showed pCR. There was no significant correlation between MRI-based response patterns after NAC and tumor reduction rates on pathology assessment (reader 1 r = − 0.17; p = 0.145 and reader 2 r = − 0.17; p = 0.146). In 41% of tumors with type 0 after NAC, pathology assessment showed pCR.ConclusionMRI-based response patterns halfway through NAC can predict pathologic response more accurately than MRI-based response patterns after NAC. Complete radiological response halfway NAC is associated with 83% pCR, while complete radiological response after NAC seems to be correct in only 41% of cases.
Gynecologic Oncology | 2017
Koen De Decker; Stephanie Speth; Henk G. ter Brugge; Joost Bart; Leon F.A.G. Massuger; Marjolein Kleppe; Loes F.S. Kooreman; Roy F.P.M. Kruitwagen; Arnold-Jan Kruse
OBJECTIVES Staging in case of a borderline tumor of the ovary (BOT) is a controversial issue. Upstaging is not uncommon, but this occurs especially with presumed stage I serous borderline tumors. There are only a few documented cases of BOTs of non-serous histology that were not confined to the ovary. The aim of this study was to assess the incidence of non-invasive and invasive implants in the omentum and other (extra)pelvic peritoneal surfaces in patients with a mucinous BOT (mBOT). METHODS A retrospective cohort study was performed in three hospitals in the Netherlands. All patients with a histopathological diagnosis of mBOT diagnosed from January 1st 1990 to December 1st 2015 were identified and included when the inclusion criteria were met. RESULTS In total, 74 patients were included. Of these 74 patients, 46 (62.2%) underwent a staging procedure. In 12 (26.1%) patients, only omental tissue was obtained, in 32 (69.6%) patients, omental tissue and peritoneal biopsies were obtained and in two (4.3%) patients, only peritoneal biopsies were obtained. No implants were seen upon microscopic examination in any of the patients. Two patients (3%) developed a recurrence. CONCLUSIONS Because no extra-ovarian disease was found, staging procedures in the case of an mBOT may be omitted. However, the actual perioperative decision for staging or not should be taken in the context of a frozen section diagnosis, which is not always accurate and straightforward. Recurrence with malignant disease is rare after mBOT. The value of post-treatment surveillance seems limited after bilateral salpingo-oophorectomy.
BMC Cancer | 2016
Margot M. Koeneman; Arnold-Jan Kruse; Loes F.S. Kooreman; A. zur Hausen; Anton H. N. Hopman; Simone J. S. Sep; T Van Gorp; B. F. M. Slangen; H. J. van Beekhuizen; M. van de Sande; C. G. Gerestein; Hans W. Nijman; Roy F.P.M. Kruitwagen
European Journal of Nuclear Medicine and Molecular Imaging | 2017
B. Goorts; Stefan Vöö; Thiemo J. A. van Nijnatten; Loes F.S. Kooreman; Maaike de Boer; Kristien Keymeulen; Romy Aarnoutse; Joachim E. Wildberger; Felix M. Mottaghy; Marc Lobbes; Marjolein L. Smidt
European Journal of Nuclear Medicine and Molecular Imaging | 2018
Thiemo J. A. van Nijnatten; B. Goorts; Stefan Vöö; M. de Boer; Loes F.S. Kooreman; E.M. Heuts; Joachim E. Wildberger; Felix M. Mottaghy; M. B. I. Lobbes; Marjolein L. Smidt
European Journal of Cancer | 2018
Evelyne M.J. Meys; Lara S. Jeelof; Bram Ramaekers; Carmen D. Dirksen; Loes F.S. Kooreman; B. F. M. Slangen; Roy F.P.M. Kruitwagen; Toon Van Gorp
European Journal of Cancer | 2018
S. Samiei; T. Van Nijnatten; L. de Munck; Kristien Keymeulen; J. Simons; Loes F.S. Kooreman; Sabine Siesling; M. B. I. Lobbes; Marjolein L. Smidt