Wiebren Tjalma

Prof. Dr. Wiebren Tjalma


Research Focus & Metrics

Academic Career Length

26Years (2001-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 July 2012 in International Journal of Cancer
Verified
Journal Article
Open access
PDF file
WTWiebren Tjalma
Wiebren Tjalma
AFAlison Fiander
Alison Fiander
OROlaf Reich
Olaf Reich
NPNed Powell
Ned Powell
ANAndrzej M. Nowakowski
Andrzej M. Nowakowski
FGfor the HERACLES/SCALE Study Group
for the HERACLES/SCALE Study Group
Knowledge of differences in human papillomavirus (HPV)‐type prevalence between high‐grade cervical intraepithelial neoplasia (HG‐CIN) and invasive cervical cancer (ICC) is crucial for understanding the natural history of HPV‐infected cervical lesions and the potential impact of HPV vaccination on cervical cancer prevention. More than 6,000 women diagnosed with HG‐CIN or ICC from 17 European countries were enrolled in two parallel cross‐sectional studies (108288/108290). Centralised histopathology review and standardised HPV‐DNA typing were applied to formalin‐fixed paraffin‐embedded cervical specimens dated 2001–2008. The pooled prevalence of individual HPV types was estimated using meta‐analytic methods. A total of 3,103 women were diagnosed with HG‐CIN and a total of 3,162 with ICC (median ages: 34 and 49 years, respectively), of which 98.5 and 91.8% were HPV‐positive, respectively. The most common HPV types in women with HG‐CIN were HPV16/33/31 (59.9/10.5/9.0%) and in ICC were HPV16/18/45 (63.3/15.2/5.3%). In squamous cell carcinomas, HPV16/18/33 were most frequent (66.2/10.8/5.3%), and in adenocarcinomas, HPV16/18/45 (54.2/40.4/8.3%). The prevalence of HPV16/18/45 was 1.1/3.5/2.5 times higher in ICC than in HG‐CIN. The difference in age at diagnosis between CIN3 and squamous cervical cancer for HPV18 (9 years) was significantly less compared to HPV31/33/‘other’ (23/20/17 years), and for HPV45 (1 year) than HPV16/31/33/‘other’ (15/23/20/17 years). In Europe, HPV16 predominates in both HG‐CIN and ICC, whereas HPV18/45 are associated with a low median age of ICC. HPV18/45 are more frequent in ICC than HG‐CIN and associated with a high median age of HG‐CIN, with a narrow age interval between HG‐CIN and ICC detection. These findings support the need for primary prevention of HPV16/18/45‐related cervical lesions.

18 March 2020 in Science Translational Medicine
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Journal Article
Closed access
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CMCornelis J. M. Melief
Cornelis J. M. Melief
MWMarij J.P. Welters
Marij J.P. Welters
IVIgnace Vergote
Ignace Vergote
Judith KroepJudith Kroep
Judith Kroep
GKGemma G. Kenter
Gemma G. Kenter
Sjoerd H. van der BurgSjoerd H. van der Burg
Sjoerd H. van der Burg
A strong vaccine-induced T cell response during standard-of-care chemotherapy correlates with survival in patients with advanced cervical cancer.

1 October 2018 in Journal of Clinical Virology
Verified
Journal Article
Open access
MAMarc Arbyn
Marc Arbyn
EPE. Peeters
E. Peeters
IBI. Benoy
I. Benoy
DBD. Vanden Broeck
D. Vanden Broeck
JBJ. Bogers
J. Bogers
AVAlex Vorsters
Alex Vorsters
Systematic reviews have concluded that hrHPV DNA testing using target-amplification tests is as accurate on vaginal self-samples as on clinician-taken specimens for the detection of cervical precancer. However, insufficient evidence is available for specific HPV assay/self-sample device combinations. The VALHUDES protocol is designed as a diagnostic test accuracy study that aims to compare the clinical sensitivity and specificity of particular hrHPV assay(s) on vaginal self-samples and first-void-urine, collected in agreement with standardized protocols, with hrHPV testing on matched clinician-taken samples. Five hundred enrolled women referred to a colposcopy clinic are invited to collect a first-void urine sample and one or more vaginal self-samples with particular devices before collection of a cervical sample by a clinician. Sample sets are subsequently analysed in a laboratory accredited for HPV testing. Disease verification for all enrolled patients is provided by colposcopy combined with histological assessment of biopsies. A first VALHUDES study has started in Belgium in December 2017 with enrolment from four colposcopy centres. The following assays are foreseen to be evaluated: RealTime High Risk HPV assay (Abbott), cobas-4800 and -6800 (Roche), Onclarity (BD), Xpert HPV (Cepheid) and Anyplex II HPV HR (Seegene). Given empirical evidence that the relative accuracy of HPV-testing on self- vs clinician-samples is robust across clinical settings, the VALHUDES protocol offers a framework for validation of HPV assay/self-sample device combinations that can be translated to a primary screening setting.

5 February 2014 in Breast Cancer Research and Treatment
Verified
Journal Article
Closed access
PDF file
HVHanne Verbelen
Hanne Verbelen
NGNick Gebruers
Nick Gebruers
FEFau-Mei Eeckhout
Fau-Mei Eeckhout
KVKim Verlinden
Kim Verlinden
WTWiebren Tjalma
Wiebren Tjalma

17 April 2009 in Proteome Science
Verified
Journal Article
Open access
PDF file
GZGeert Zegels
Geert Zegels
GRGeert Aa Van Raemdonck
Geert Aa Van Raemdonck
ECEdmond P Coen
Edmond P Coen
WTWiebren Tjalma
Wiebren Tjalma
XOXaveer Van Ostade
Xaveer Van Ostade
Background: Cervical-vaginal fluid (CVF) plays an important role in the prevention of gynecological infections, although little is known about the contribution of CVF proteins to the immunity of the lower female genital tract. In order to analyze the protein composition of human CVF, we used CVF samples that are routinely collected during colposcopy, but are usually discarded. Since these samples are available in large quantities we aimed to analyze their usefulness for proteomics experiments. The samples were analyzed using different prefractionation techniques (ultrafiltration and C4(RP)-LC protein separation) followed by C18(RP)-LC peptide separation and identification by MALDI-TOF-TOF mass spectrometry. To determine the reproducibility of this proteomics platform we analyzed three technical replicates. Using spectral counting, protein abundances were estimated in a semiquantitative way. We also compared the results obtained in this study with those from previous studies derived from patients with different physiological conditions in order to determine an overlapping protein set.Results: In total, we were able to identify 339 proteins in human CVF of which 151 proteins were not identified in any other proteomics study on human CVF so far. Those included antimicrobial peptides, such as human beta-defensin 2 and cathelicidin, which were known to be present in CVF, and endometrial proteins such as glycodelin and ribonucleoprotein A. Comparison of our results with previously published data led to the identification of a common protein set of 136 proteins. This overlapping protein set shows increased fractions of immunological and extracellular proteins, confirming the extracellular immunological role of CVF.Conclusion: We demonstrated here that CVF colposcopy samples can be used in proteomics experiments and hence are applicable for biomarker discovery experiments. The delineation of an overlapping set of proteins that is identified in most proteomics studies on CVF may help in the description of a reference proteome when performing proteomics studies on human CVF.

1 August 2005 in Best Practice & Research Clinical Obstetrics & Gynaecology
Verified
Journal Article
Closed access
WTWiebren Tjalma
Wiebren Tjalma
TWT.R. Van Waes
T.R. Van Waes
LEL.E.M. Van Den Eeden
L.E.M. Van Den Eeden
JBJohannes Bogers
Johannes Bogers