Geert 11761447140 Roeyen

Prof. Dr. Geert 11761447140 Roeyen

orcid

Research Focus & Metrics

Academic Career Length

23Years (2004-Present)

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

Representative Publications

View All Publications
30 March 2019 in Cancers
Verified
Journal Article
Open access
PDF file
LSLaure Sorber
Laure Sorber
UAUniveristy of Antwerp
Univeristy of Antwerp
JJJulie Jacobs
Julie Jacobs
KWKoen De Winne
Koen De Winne
SGSofie Goethals
Sofie Goethals
Patrick PauwelsPatrick Pauwels
Patrick Pauwels
The combined analysis of circulating cell-free (tumor) DNA (cfDNA/ctDNA) and circulating cell-free (tumor) RNA (cfRNA/ctRNA) shows great promise in determining the molecular profile of cancer patients. Optimization of the workflow is necessary to achieve consistent and reproducible results. In this study, we compared five centrifugation protocols for the optimal yield of both cfDNA/ctDNA and cfRNA/ctRNA. These protocols varied in centrifugation speed, ambient temperature, time, and number of centrifugation steps. Samples from 33 participants were collected in either BD Vacutainer K2EDTA (EDTA) tubes or cell-free DNA BCT® (Streck) tubes. cfDNA concentration and fragment size, and cfRNA concentration were quantitated in all samples by digital droplet PCR (ddPCR) and quantitative PCR (qPCR). The KRAS-mutated ctDNA and ctRNA fraction was determined via ddPCR. In EDTA tubes, the protocol generating both plasma and platelets was found to produce high quality cfDNA and cfRNA concentrations. Two-step, high-speed centrifugation protocols were associated with high cfDNA but low cfRNA concentrations. High cfRNA concentrations were generated by a one-step, low-speed protocol. However, this coincided with a high amount of genomic DNA (gDNA) contamination. In Streck tubes, two-step, high-speed centrifugation protocols also generated good quality, high cfDNA concentration. However, these tubes are not compatible with cfRNA analysis.

27 February 2021 in Cancers
Verified
Journal Article
Open access
PDF file
ADAndreas Domen
Andreas Domen
DQDelphine Quatannens
Delphine Quatannens
SZSara Zanivan
Sara Zanivan
CDChristophe Deben
Christophe Deben
JAJonas Van Audenaerde
Jonas Van Audenaerde
HPHans Prenen
Hans Prenen
Cancer arises from mutations accruing within cancer cells, but the tumor microenvironment (TME) is believed to be a major, often neglected, factor involved in therapy resistance and disease progression. Cancer-associated fibroblasts (CAFs) are prominent and key components of the TME in most types of solid tumors. Extensive research over the past decade revealed their ability to modulate cancer metastasis, angiogenesis, tumor mechanics, immunosuppression, and drug access through synthesis and remodeling of the extracellular matrix and production of growth factors. Thus, they are considered to impede the response to current clinical cancer therapies. Therefore, targeting CAFs to counteract these protumorigenic effects, and overcome the resistance to current therapeutic options, is an appealing and emerging strategy. In this review, we discuss how CAFs affect prognosis and response to clinical therapy and provide an overview of novel therapies involving CAF-targeting agents in lung and pancreatic cancer.

14 December 2019 in Molecular Diagnosis & Therapy
Verified
Journal Article
Closed access
PDF file
LSLaure Sorber
Laure Sorber
UAUniveristy of Antwerp
Univeristy of Antwerp
JJJulie Jacobs
Julie Jacobs
KWKoen De Winne
Koen De Winne
KCKaat Van Casteren
Kaat Van Casteren
Patrick PauwelsPatrick Pauwels
Patrick Pauwels

3 February 2022 in ESMO Open
Verified
Journal Article
Open access
GRGeert 11761447140 Roeyen
Geert 11761447140 Roeyen
FBF. Berrevoet
F. Berrevoet
IBI. Borbath
I. Borbath
KGK. Geboes
K. Geboes
MPM. Peeters
M. Peeters
JLJ.-L. Van Laethem
J.-L. Van Laethem
Pancreatic exocrine insufficiency (PEI) is a common condition in patients with pancreatic cancer (PC). PEI can be due to the tumor, which, if located in the head, causes obstruction of the pancreatic duct with subsequent atrophy of the pancreatic parenchyma, or it can be the consequence of pancreatic surgical resection. The standard treatment of PEI is pancreatic enzyme replacement therapy (PERT). Clinical data to support the use of PERT in PC are however limited. There are very few randomized clinical trials that evaluated PERT in PC. Most data come from observational studies. Despite this limited clinical evidence, PERT treatment for PEI is an essential part of supportive therapy to ensure optimal nutritional status in PC patients who will receive surgery, neoadjuvant/adjuvant or palliative treatment. The objective of this review is to increase the awareness about PEI in PC patients and to provide expert recommendations on the use of PERT in resected, borderline resectable and unresectable patients, based on clinical experience and literature review.

6 January 2022 in Pharmacology & Therapeutics
Verified
Journal Article
Closed access
DQDelphine Quatannens
Delphine Quatannens
YVYannick Verhoeven
Yannick Verhoeven
Peter Van DamPeter Van Dam
Peter Van Dam
FLFilip Lardon
Filip Lardon
HPHans Prenen
Hans Prenen
JAJonas Van Audenaerde
Jonas Van Audenaerde

10 November 2021 in Clinical Cancer Research
Verified
Journal Article
Open access
PDF file
GBGitta Boons
Gitta Boons
TVTimon Vandamme
Timon Vandamme
LMLaura Mariën
Laura Mariën
WLWillem Lybaert
Willem Lybaert
GRGeert 11761447140 Roeyen
Geert 11761447140 Roeyen
KBKen Op de Beeck
Ken Op de Beeck
Purpose: As noninvasive biomarkers are an important unmet need for neuroendocrine neoplasms (NEN), biomarker potential of genome-wide molecular profiling of plasma cell-free DNA (cfDNA) was prospectively studied in patients with NEN. Experimental Design: Longitudinal plasma samples were collected from patients with well-differentiated, metastatic gastroenteropancreatic and lung NEN. cfDNA was subjected to shallow whole-genome sequencing to detect genome-wide copy-number alterations (CNA) and estimate circulating tumor DNA (ctDNA) fraction, and correlated to clinicopathologic and survival data. To differentiate pancreatic NENs (PNEN) from pancreatic adenocarcinomas (PAAD) using liquid biopsies, a classification model was trained using tissue-based CNAs and validated in cfDNA. Results: One hundred and ninety-five cfDNA samples from 43 patients with NEN were compared with healthy control cfDNA (N = 100). Plasma samples from patients with PNEN (N = 21) were used for comparison with publicly available PNEN tissue (N = 98), PAAD tissue (N = 109), and PAAD cfDNA (N = 96). Thirty percent of the NEN cfDNA samples contained ctDNA and 44% of the patients had at least one ctDNA-positive (ctDNA+) sample. CNAs detected in cfDNA were highly specific for NENs and the classification model could distinguish PAAD and PNEN cfDNA samples with a sensitivity, specificity, and AUC of 62%, 86%, and 79%, respectively. ctDNA-positivity was associated with higher World Health Organization (WHO) grade, primary tumor location, and higher chromogranin A and neuron-specific enolase values. Overall survival was significantly worse for ctDNA+ patients and increased ctDNA fractions were associated with poorer progression-free survival. Conclusions: Sequential genome-wide profiling of plasma cfDNA is a novel, noninvasive biomarker with high specificity for diagnosis, prognosis, and follow-up in metastatic NENs.