1
|
Collée GE, van der Wilk BJ, van Lanschot JJB, Busschbach JJ, Timmermans L, Lagarde SM, Kranenburg LW. Interventions that Facilitate Shared Decision-Making in Cancers with Active Surveillance as Treatment Option: a Systematic Review of Literature. Curr Oncol Rep 2020; 22:101. [PMID: 32725550 PMCID: PMC7387328 DOI: 10.1007/s11912-020-00962-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
PURPOSE OF REVIEW Medical decisions concerning active surveillance are complex, especially when evidence on superiority of one of the treatments is lacking. Decision aids have been developed to facilitate shared decision-making on whether to pursue an active surveillance strategy. However, it is unclear how these decision aids are designed and which outcomes are considered relevant. The purpose of this study is to systematically review all decision aids in the field of oncological active surveillance strategies and outcomes used by authors to assess their efficacy. RECENT FINDINGS A search was performed in Embase, Medline, Web of Science, Cochrane, PsycINFO Ovid and Google Scholar until June 2019. Eligible studies concerned interventions aiming to facilitate shared decision-making for patients confronted with several treatment alternatives, with active surveillance being one of the treatment alternatives. Twenty-three eligible articles were included. Twenty-one articles included patients with prostate cancer, one with thyroid cancer and one with ovarian cancer. Interventions mostly consisted of an interactive web-based decision aid format. After categorization of outcomes, seven main groups were identified: knowledge, involvement in decision-making, decisional conflict, treatment preference, decision regret, anxiety and health-related outcomes. Although active surveillance has been implemented for several malignancies, interventions that facilitate shared decision-making between active surveillance and other equally effective treatment alternatives are scarce. Future research should focus on developing interventions for malignancies like rectal cancer and oesophageal cancer as well. The efficacy of interventions is mostly assessed using short-term outcomes.
Collapse
|
2
|
Jairam AP, López-Cano M, Garcia-Alamino JM, Pereira JA, Timmermans L, Jeekel J, Lange J, Muysoms F. Prevention of incisional hernia after midline laparotomy with prophylactic mesh reinforcement: a meta-analysis and trial sequential analysis. BJS Open 2020; 4:357-368. [PMID: 32057193 PMCID: PMC7260413 DOI: 10.1002/bjs5.50261] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Accepted: 12/17/2019] [Indexed: 02/04/2023] Open
Abstract
Background Incisional hernia is a frequent complication after abdominal surgery. The aim of this study was to assess the efficacy of prophylactic mesh reinforcement (PMR) after midline laparotomy in reducing the incidence of incisional hernia. Methods A meta‐analysis was conducted following PRISMA guidelines. The primary outcome was the incidence of incisional hernia after follow‐up of at least 12 months. Secondary outcomes were postoperative complications. Only RCTs were included. A random‐effects model was used for the meta‐analysis, and trial sequential analysis was conducted. Results Twelve RCTs were included, comprising 1815 patients. The incidence of incisional hernia was significantly lower after PMR compared with sutured closure (risk ratio (RR) 0·35, 95 per cent c.i. 0·21 to 0·57; P < 0·001). Both onlay (RR 0·26, 0·11 to 0·67; P = 0·005) and retromuscular (RR 0·28, 0·10 to 0·82; P = 0·02) PMR led to a significant reduction in the rate of incisional hernia. The occurrence of seroma was higher in patients who had onlay PMR (RR 2·23, 1·10 to 4·52; P = 0·03). PMR did not result in an increased rate of surgical‐site infection. Conclusion PMR of a midline laparotomy using an onlay or retromuscular technique leads to a significant reduction in the rate of incisional hernia in high‐risk patients. Individual risk factors should be taken into account to select patients who will benefit most. [Correction added on 19 February 2020, after first online publication: J. García Alamino has been amended to J. M. Garcia‐Alamino]
Collapse
|
3
|
Jiang J, Mathijs K, Timmermans L, Claessen SM, Hecka A, Weusten J, Peters R, van Delft JH, Kleinjans JCS, Jennen DGJ, de Kok TM. The idiosyncratic drug-induced gene expression changes in HepG2 cells. Data Brief 2017; 14:462-468. [PMID: 28831409 PMCID: PMC5554930 DOI: 10.1016/j.dib.2017.07.074] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 07/27/2017] [Indexed: 11/09/2022] Open
Abstract
The inflammatory stress has been associated with an increase in susceptibility to idiosyncratic drug-induced liver injury (DILI). However, the molecular mechanisms of this inflammation-associated idiosyncratic drug hepatotoxicity remain unknown. We exposed HepG2 cells with high and low doses of three idiosyncratic (I) and three non-idiosyncratic (N) compounds, in the presence (I+ and N+) or absence (I− and N−) of a cytokine mix for 6, 12 and 24 h. To investigate the genome‐wide expression patterns, microarray was performed using the Agilent 4×44K Whole Human Genome chips. The data presented in this DIB include the expression of genes participating in the ceramide metabolism, ER stress, apoptosis and cell survival pathways. The functions of these genes were illustrated in our associated article (Jiang et al., 2017) [1]. Raw and normalized gene expression data are available through NCBI GEO (accession number GSE102006).
Collapse
|
4
|
Jiang J, Mathijs K, Timmermans L, Claessen SM, Hecka A, Weusten J, Peters R, van Delft JH, Kleinjans JCS, Jennen DGJ, de Kok TM. Omics-based identification of the combined effects of idiosyncratic drugs and inflammatory cytokines on the development of drug-induced liver injury. Toxicol Appl Pharmacol 2017; 332:100-108. [PMID: 28733206 DOI: 10.1016/j.taap.2017.07.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 07/08/2017] [Accepted: 07/17/2017] [Indexed: 12/13/2022]
Abstract
The mechanisms of idiosyncratic drug-induced hepatotoxicity remain largely unclear. It has demonstrated that the drug idiosyncrasy is potentiated in the context of inflammation and intracellular ceramides may play a role in this process. To study the mechanisms, HepG2 cells were co-treated with high and low doses of three idiosyncratic (I) and three non-idiosyncratic (N) compounds, with (I+ and N+) or without (I- and N-) a cytokine mix. Microarray, lipidomics and flow cytometry were performed to investigate the genome-wide expression patterns, the intracellular ceramide levels and the induction of apoptosis. We found that all I+ treatments significantly influenced the immune response- and response to stimulus-associated gene ontology (GO) terms, but the induction of apoptotic pathways, which was confirmed by flow cytometry, only appeared to be induced after the high-dose treatment. The ceramide signaling-, ER stress-, NF-kB activation- and mitochondrial activity-related pathways were biologically involved in apoptosis induced by the high-dose I+. Additionally, genes participating in ceramide metabolism were significantly altered resulting in a measurable increase in ceramide levels. The increases in ceramide concentrations may induce ER stress and activate the JNK pathway by affecting the expression of the related genes, and eventually trigger the mitochondria-independent apoptosis in hepatocytes. Overall, our study provides a potential mechanism to explain the role of inflammation in idiosyncratic drug reactions.
Collapse
|
5
|
Timmermans L, De Mol J, Mélot C, Falez F. [Correlation between ICIQ-UI-SF score and personality testing results over a urinary incontinent population]. Prog Urol 2015; 26:230-6. [PMID: 26746787 DOI: 10.1016/j.purol.2015.11.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2015] [Revised: 11/19/2015] [Accepted: 11/30/2015] [Indexed: 10/22/2022]
Abstract
OBJECTIVE We found out the personality pattern of an incontinent population and proceeded to a correlation between the personality inventory and the ICIQ-UI-SF (International Consultation Incontinence Questionnaire Urinary Incontinence Short Form) to demonstrate reliability and sincerity of the answers and to establish that a personality disturbance may impact the physiopathology of micturition. MATERIALS AND METHODS We performed an observational prospective study. It included patient's answers to a computed questionnaire combining a double ICIQ-UI-SF questionnaire and the 71 questions of the Minimult questionnaire. Forty-seven patients were asked to participate. RESULTS Over 37 patients included, Wilcoxon-Mann-Whitney non parametric test confirmed agreement of the two ICIQ-UI-SF questionnaires with P=0.1792. Twenty-three patients were validated to the Minimult inventory with F scale<70. We analysed variability of the two global ICIQ-UI-SF score in regard with the validity scale using ROC analysis. We observed an AUC of 0.559 with sensitivity 78.6% and specificity 43.5%. No L score was above 70 demonstrating absence of lie. No personality disturbance was found in 9 cases. We observed six cases with a high hypochondric value, five with a high depressive value, and four with a high hysteric value. This neurotic triad was found in two cases. We noticed five cases with psychopathic deviance relative to antisocial behaviour while values of paranoia and hypomania were high in one case without any association of these personality aspects, which demonstrated absence of behavioural problem. Psychotic profile associating schizophrenia, paranoia, depression and hypomania was not found. We outlined in half of the valid population a significant high psycho-asthenic pattern. CONCLUSION We conclude that a correlation between the personality inventory and the ICIQ-UI-SF is feasible. The comparative study demonstrate reliability of answers. Sincerity is established by the Minimult L scale. We confirm and precise literature information over clinical personality pattern of this population and observe relevant elements concerning the psycho-asthenic pattern which depicts an anxious personality with an important feeling of the problem. These elements permit to suspect that a personality disturbance may impact the physiopathology of the micturition. LEVEL OF EVIDENCE 4.
Collapse
|
6
|
Deerenberg EB, Timmermans L, Hogerzeil DP, Slieker JC, Eilers PHC, Jeekel J, Lange JF. A systematic review of the surgical treatment of large incisional hernia. Hernia 2014; 19:89-101. [PMID: 25380560 DOI: 10.1007/s10029-014-1321-x] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2013] [Accepted: 10/26/2014] [Indexed: 01/12/2023]
Abstract
PURPOSE Incisional hernia (IH) is one of the most frequent postoperative complications. Of all patients undergoing IH repair, a vast amount have a hernia which can be defined as a large incisional hernia (LIH). The aim of this study is to identify the preferred technique for LIH repair. METHODS A systematic review of the literature was performed and studies describing patients with IH with a diameter of 10 cm or a surface of 100 cm2 or more were included. Recurrence hazards per year were calculated for all techniques using a generalized linear model. RESULTS Fifty-five articles were included, containing 3,945 LIH repairs. Mesh reinforced techniques displayed better recurrence rates and hazards than techniques without mesh reinforcement. Of all the mesh techniques, sublay repair, sandwich technique with sublay mesh and aponeuroplasty with intraperitoneal mesh displayed the best results (recurrence rates of <3.6%, recurrence hazard <0.5% per year). Wound complications were frequent and most often seen after complex LIH repair. CONCLUSIONS The use of mesh during LIH repair displayed the best recurrence rates and hazards. If possible mesh in sublay position should be used in cases of LIH repair.
Collapse
|
7
|
Timmermans L, Larroumets A, Hoffmann P, Defourny C, Falez F. Objectivation de l’impact qualitatif d’une infirmière référente en consultation d’urologie. Prog Urol 2013. [DOI: 10.1016/j.purol.2013.08.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
8
|
Meijer EJ, Timmermans L, Jeekel J, Lange J, Muysoms F. The principles of abdominal wound closure. Acta Chir Belg 2013; 113:239-44. [PMID: 24224430 DOI: 10.1080/00015458.2013.11680920] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
BACKGROUND Incisional hernia (IH) is a common complication of abdominal surgery. Its incidence has been reported as high as 39.9%. Many factors influence IH rates. Of these, surgical technique is the only factor directly controlled by the surgeon. There is much evidence in the literature on the optimal midline laparotomy closure technique. Despite the high level of evidence, this optimal closure technique has not met wide acceptance in the surgical community. In preparation of a clinical trial, the PRINCIPLES trial, a literature review was conducted to find the best evidence based technique for abdominal wall closure after midline laparotomy. METHODS An Embase search was performed. Articles describing closure of the fascia after midline laparotomy by different suture techniques and/or suture materials were selected. RESULTS Fifteen studies were identified, including five meta-analyses. Analysis of the literature showed significant lower IH rates with single layer closure, using a continuous technique with slowly absorbable suture material. No significant difference in IH incidence was found comparing slowly absorbable and non absorbable sutures. Furthermore, a suture length to wound length ratio of four or more and short stitch length significantly decreased IH rates. CONCLUSIONS Careful analysis of the literature indicates that an evidenced based optimal midline laparotomy closure technique can be identified. This technique involves single layer closure with a running suture, using a slowly absorbable suture with a suture length to wound length ratio of four or more and a short stitch length. We adopt this technique as the PRINCIPLES technique.
Collapse
|
9
|
de Goede B, Klitsie PJ, van Kempen BJH, Timmermans L, Jeekel J, Kazemier G, Lange JF. Meta-analysis of glue versus sutured mesh fixation for Lichtenstein inguinal hernia repair. Br J Surg 2013; 100:735-42. [DOI: 10.1002/bjs.9072] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2012] [Indexed: 11/07/2022]
Abstract
Abstract
Background
Chronic pain remains a frequent complication after Lichtenstein inguinal hernia repair. As a consequence, mesh fixation using glue instead of sutures has become popular. This meta-analysis aimed to clarify which fixation technique is to be preferred for elective Lichtenstein inguinal hernia repair.
Methods
A meta-analysis was conducted according to the PRISMA guidelines. Articles published between January 1990 and April 2012 were searched for in MEDLINE, Embase and the Cochrane Library. Randomized controlled trials (RCTs) comparing glue and sutured mesh fixation in elective Lichtenstein repair for unilateral inguinal hernia were included. The quality of the RCTs and the potential risk of bias were assessed using the Cochrane risk of bias tool.
Results
Of 254 papers found in the initial search, a meta-analysis was conducted of seven RCTs comprising 1185 patients. With the use of glue mesh fixation, the duration of operation was shorter (mean difference −2·57 (95 per cent confidence interval (c.i.) –4·88 to −0·26) min; P = 0·03), patients had lower visual analogue scores for postoperative pain (mean difference −0·75 (−1·18 to −0·33); P = 0·001), early chronic pain occurred less often (risk ratio 0·52, 95 per cent c.i. 0·31 to 0·87; P = 0·01), and time to return to daily activities was shorter (mean difference −1·17 (−2·30 to −0·03) days; P = 0·04). The hernia recurrence rate did not differ significantly.
Conclusion
Elective Lichtenstein repair for inguinal hernia using glue mesh fixation compared with sutures is faster and less painful, with comparable hernia recurrence rates.
Collapse
|
10
|
Boesten DM, Houben JM, Timmermans L, Bast A, Hageman GJ. Accelerated aging during chronic oxidative stress: a role for PARP‐1? FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.939.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
11
|
Lizarraga D, Gaj S, Brauers KJ, Timmermans L, Kleinjans JC, van Delft JHM. Benzo[a]pyrene-induced changes in microRNA-mRNA networks. Chem Res Toxicol 2012; 25:838-49. [PMID: 22316170 DOI: 10.1021/tx2003799] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Toxicological studies assessing the safety of compounds for humans frequently use in vitro systems to characterize toxic responses in combination with transcriptomic analyses. Thus far, changes have mostly been investigated at the mRNA level. Recently, microRNAs have attracted attention because they are powerful negative regulators of mRNA levels and, thus, may be responsible for the modulation of important mRNA networks implicated in toxicity. This study aimed to identify possible microRNA-mRNA networks as novel interactions on the gene expression level after a genotoxic insult. We used benzo[a]pyrene (BaP), a polycyclic aromatic hydrocarbon, as a model genotoxic/carcinogenic compound. We analyzed time-dependent effects on mRNA and microRNA profiles in HepG2 cells, a widely used human liver cell line that expresses active p53 and is competent for the biotransformation of BaP. Changes in microRNA expression in response to BaP, in combination with multiple alterations of mRNA levels, were observed. Many of these altered mRNAs are targets of altered microRNAs. Using pathway analysis, we evaluated the relevance of such microRNA deregulations to genotoxicity. This revealed eight microRNAs that appear to participate in specific BaP-responsive pathways relevant to genotoxicity, such as apoptotic signaling, cell cycle arrest, DNA damage response, and DNA damage repair. Our results particularly highlight the potential of microRNA-29b, microRNA-26a-1*, and microRNA-122* as novel players in the BaP response. Therefore, this study demonstrates the added value of an integrated microRNA-mRNA approach for identifying molecular mechanisms induced by BaP in an in vitro human model.
Collapse
|
12
|
Rysman E, Brusselmans K, Scheys K, Timmermans L, Derua R, Munck S, Van Veldhoven PP, Waltregny D, Daniëls VW, Machiels J, Vanderhoydonc F, Smans K, Waelkens E, Verhoeven G, Swinnen JV. De novo lipogenesis protects cancer cells from free radicals and chemotherapeutics by promoting membrane lipid saturation. Cancer Res 2010; 70:8117-26. [PMID: 20876798 DOI: 10.1158/0008-5472.can-09-3871] [Citation(s) in RCA: 492] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Activation of de novo lipogenesis in cancer cells is increasingly recognized as a hallmark of aggressive cancers and has been implicated in the production of membranes for rapid cell proliferation. In the current report, we provide evidence that this activation has a more profound role. Using a mass spectrometry-based phospholipid analysis approach, we show that clinical tumor tissues that display the lipogenic phenotype show an increase in the degree of lipid saturation compared with nonlipogenic tumors. Reversal of the lipogenic switch in cancer cells by treatment with the lipogenesis inhibitor soraphen A or by targeting lipogenic enzymes with small interfering RNA leads to a marked decrease in saturated and mono-unsaturated phospholipid species and increases the relative degree of polyunsaturation. Because polyunsaturated acyl chains are more susceptible to peroxidation, inhibition of lipogenesis increases the levels of peroxidation end products and renders cells more susceptible to oxidative stress-induced cell death. As saturated lipids pack more densely, modulation of lipogenesis also alters lateral and transversal membrane dynamics as revealed by diffusion of membrane-targeted green fluorescent protein and by the uptake and response to doxorubicin. These data show that shifting lipid acquisition from lipid uptake toward de novo lipogenesis dramatically changes membrane properties and protects cells from both endogenous and exogenous insults. These findings provide important new insights into the role of de novo lipogenesis in cancer cells, and they provide a rationale for the use of lipogenesis inhibitors as antineoplastic agents and as chemotherapeutic sensitizers.
Collapse
|
13
|
Schults MA, Timmermans L, Godschalk RW, Theys J, Wouters BG, van Schooten FJ, Chiu RK. Diminished carcinogen detoxification is a novel mechanism for hypoxia-inducible factor 1-mediated genetic instability. J Biol Chem 2010; 285:14558-64. [PMID: 20228066 DOI: 10.1074/jbc.m109.076323] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The hypoxia-inducible factor 1 (HIF-1) pathway is induced in many tumors and associated with poorer outcome. The hypoxia-responsive transcription factor HIF-1alpha dimerizes with the aryl hydrocarbon receptor nuclear translocator (ARNT), which is also an important binding partner for the aryl hydrocarbon receptor (AhR). AhR is an important mediator in the metabolic activation and detoxification of carcinogens, such as the environmental pollutant benzo[a]pyrene (BaP). We hypothesized that HIF-1alpha activation attenuates BaP-induced AhR-mediated gene expression, which may lead to increased genetic instability and malignant progression. Human lung carcinoma cells (A549) were simultaneously stimulated with CoCl(2), which leads to HIF-1alpha stabilization and varying concentrations of BaP. Both quantitative PCR and immunoblot analysis indicated that induction of the hypoxia response pathway significantly reduced the levels of AhR downstream targets CYP1A1 and CYP1B1 and AhR protein binding to ARNT. We further demonstrate that the BaP-induced hypoxanthine-guanine phosphoribosyltransferase mutation frequency and gamma-H2AX foci were markedly amplified when the HIF-1 pathway was induced. BaP-DNA adducts were only marginally increased, and transient strand breaks were diminished by HIF-1 induction, indicating changes in DNA repair. These data indicate that concurrent exposure of tumor cells to hypoxia and exogenous genotoxins can enhance genetic instability.
Collapse
|
14
|
Beckers A, Organe S, Timmermans L, Scheys K, Peeters A, Brusselmans K, Verhoeven G, Swinnen JV. Chemical inhibition of acetyl-CoA carboxylase induces growth arrest and cytotoxicity selectively in cancer cells. Cancer Res 2007; 67:8180-7. [PMID: 17804731 DOI: 10.1158/0008-5472.can-07-0389] [Citation(s) in RCA: 232] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Development and progression of cancer is accompanied by marked changes in the expression and activity of enzymes involved in the cellular homeostasis of fatty acids. One class of enzymes that play a particularly important role in this process are the acetyl-CoA carboxylases (ACC). ACCs produce malonyl-CoA, an intermediate metabolite that functions as substrate for fatty acid synthesis and as negative regulator of fatty acid oxidation. Here, using the potent ACC inhibitor soraphen A, a macrocyclic polyketide from myxobacteria, we show that ACC activity in cancer cells is essential for proliferation and survival. Even at nanomolar concentrations, soraphen A can block fatty acid synthesis and stimulate fatty acid oxidation in LNCaP and PC-3M prostate cancer cells. As a result, the phospholipid content of cancer cells decreased, and cells stopped proliferating and ultimately died. LNCaP cells predominantly died through apoptosis, whereas PC-3M cells showed signs of autophagy. Supplementation of the culture medium with exogenous palmitic acid completely abolished the effects of soraphen A and rescued the cells from cell death. Interestingly, when added to cultures of premalignant BPH-1 cells, soraphen A only slightly affected cell proliferation and did not induce cell death. Together, these findings indicate that cancer cells have become dependent on ACC activity to provide the cell with a sufficient supply of fatty acids to permit proliferation and survival, introducing the concept of using small-molecule ACC inhibitors as therapeutic agents for cancer.
Collapse
|
15
|
Brusselmans K, Timmermans L, Van de Sande T, Van Veldhoven PP, Guan G, Shechter I, Claessens F, Verhoeven G, Swinnen JV. Squalene synthase, a determinant of Raft-associated cholesterol and modulator of cancer cell proliferation. J Biol Chem 2007; 282:18777-85. [PMID: 17483544 DOI: 10.1074/jbc.m611763200] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Several cues for cell proliferation, migration, and survival are transmitted through lipid rafts, membrane microdomains enriched in sphingolipids and cholesterol. Cells obtain cholesterol from the circulation but can also synthesize cholesterol de novo through the mevalonate/isoprenoid pathway. This pathway, however, has several branches and also produces non-sterol isoprenoids. Squalene synthase (SQS) is the enzyme that determines the switch toward sterol biosynthesis. Here we demonstrate that in prostate cancer cells SQS expression is enhanced by androgens, channeling intermediates of the mevalonate/isoprenoid pathway toward cholesterol synthesis. Interestingly, the resulting increase in de novo synthesis of cholesterol mainly affects the cholesterol content of lipid rafts, while leaving non-raft cholesterol levels unaffected. Conversely, RNA interference-mediated SQS inhibition results in a decrease of raft-associated cholesterol. These data show that SQS activity and de novo cholesterol synthesis are determinants of membrane microdomain-associated cholesterol in cancer cells. Remarkably, SQS knock down also attenuates proliferation and induces death of prostate cancer cells. Similar effects are observed when cancer cells are treated with the chemical SQS inhibitor zaragozic acid A. Importantly, although the anti-tumor effect of statins has previously been attributed to inhibition of protein isoprenylation, the present study shows that specific inhibition of the cholesterol biosynthesis branch of the mevalonate/isoprenoid pathway also induces cancer cell death. These findings significantly underscore the importance of de novo cholesterol synthesis for cancer cell biology and suggest that SQS is a potential novel target for antineoplastic intervention.
Collapse
|
16
|
Geudens N, Timmermans L, Vanaudenaerde B, Van De Wauwer C, Lerut T, Verbeken E, Verleden G, Van Raemdonck D. 143: Azithromycin reduces inflammation in a murine lung ischemia-reperfusion injury model. J Heart Lung Transplant 2007. [DOI: 10.1016/j.healun.2006.11.159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
17
|
Beckers A, Organe S, Timmermans L, Vanderhoydonc F, Deboel L, Derua R, Waelkens E, Brusselmans K, Verhoeven G, Swinnen JV. Methotrexate enhances the antianabolic and antiproliferative effects of 5-aminoimidazole-4-carboxamide riboside. Mol Cancer Ther 2006; 5:2211-7. [PMID: 16985054 DOI: 10.1158/1535-7163.mct-06-0001] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Because of its ability to mimic a low energy status of the cell, the cell-permeable nucleoside 5-aminoimidazole-4-carboxamide (AICA) riboside was proposed as an antineoplastic agent switching off major energy-consuming processes associated with the malignant phenotype (lipid production, DNA synthesis, cell proliferation, cell migration, etc.). Key to the antineoplastic action of AICA riboside is its conversion to ZMP, an AMP mimetic that at high concentrations activates the AMP-activated protein kinase (AMPK). Here, in an attempt to increase the efficacy of AICA riboside, we pretreated cancer cells with methotrexate, an antimetabolite blocking the metabolism of ZMP. Methotrexate enhanced the AICA riboside-induced accumulation of ZMP and led to a decrease in the levels of ATP, which functions as an intrasteric inhibitor of AMPK. Consequently, methotrexate markedly sensitized AMPK for activation by AICA riboside and potentiated the inhibitory effects of AICA riboside on tumor-associated processes. As cotreatment elicited antiproliferative effects already at concentrations of compounds that were only marginally effective when used alone, our findings on the cooperation between methotrexate and AICA riboside provide new opportunities both for the application of classic antimetabolic chemotherapeutics, such as methotrexate, and for the exploitation of the energy-sensing machinery as a target for cancer intervention.
Collapse
|
18
|
Van Lierde KM, Schepers S, Timmermans L, Verhoye I, Van Cauwenberge P. The impact of mandibular advancement on articulation, resonance and voice characteristics in Flemish speaking adults: a pilot study. Int J Oral Maxillofac Surg 2006; 35:137-44. [PMID: 16185844 DOI: 10.1016/j.ijom.2005.06.011] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2005] [Revised: 04/20/2005] [Accepted: 06/14/2005] [Indexed: 11/21/2022]
Abstract
Bilateral saggital split osteotomy (BSSO) of the mandible is a frequently performed mandibular orthognathic procedure, used to resolve mandibular disharmonies. Literature review showed contradictory findings regarding the effect of the orthognathic surgery on speech characteristics. The purpose of the present study was to determine a detailed analysis of the articulation, resonance and voice characteristics after BSSO with mandibular advancement for the treatment of Class II malocclusions using objective and subjective assessment techniques (perceptual evaluations, Dysphonia Severity Index, nasalance scores) in eight subjects. The findings of the present study indicate that before and after BSSO with mandibular advancement three types of articulation disorders may predominate in the Flemish language: the incorrect production of the trill sound /r/ and the /s/ sound and devoicing of the /z/. After orthognathic surgery most patients showed an identical articulation pattern (normal or disturbed pattern) as in the presurgical condition. In this study the BSSO with mandibular advancement had no significant impact on the nasality characteristics and the nasalance values probably due to the competent velopharyngeal valving in the presurgical condition. And, as expected the vocal quality revealed no significant difference. The maxillofacial surgeon and the speech language pathologist must be aware of the persistency of these preoperative articulation errors in the postsurgical condition.
Collapse
|
19
|
Swinnen JV, Beckers A, Brusselmans K, Organe S, Segers J, Timmermans L, Vanderhoydonc F, Deboel L, Derua R, Waelkens E, De Schrijver E, Van de Sande T, Noël A, Foufelle F, Verhoeven G. Mimicry of a cellular low energy status blocks tumor cell anabolism and suppresses the malignant phenotype. Cancer Res 2005; 65:2441-8. [PMID: 15781660 DOI: 10.1158/0008-5472.can-04-3025] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Aggressive cancer cells typically show a high rate of energy-consuming anabolic processes driving the synthesis of lipids, proteins, and DNA. Here, we took advantage of the ability of the cell-permeable nucleoside 5-aminoimidazole-4-carboxamide (AICA) riboside to increase the intracellular levels of AICA ribotide, an AMP analogue, mimicking a low energy status of the cell. Treatment of cancer cells with AICA riboside impeded lipogenesis, decreased protein translation, and blocked DNA synthesis. Cells treated with AICA riboside stopped proliferating and lost their invasive properties and their ability to form colonies. When administered in vivo, AICA riboside attenuated the growth of MDA-MB-231 tumors in nude mice. These findings point toward a central tie between energy, anabolism, and cancer and suggest that the cellular energy sensing machinery in cancer cells is an exploitable target for cancer prevention and/or therapy.
Collapse
|
20
|
Swinnen JV, Van Veldhoven PP, Timmermans L, De Schrijver E, Brusselmans K, Vanderhoydonc F, Van de Sande T, Heemers H, Heyns W, Verhoeven G. Fatty acid synthase drives the synthesis of phospholipids partitioning into detergent-resistant membrane microdomains. Biochem Biophys Res Commun 2003; 302:898-903. [PMID: 12646257 DOI: 10.1016/s0006-291x(03)00265-1] [Citation(s) in RCA: 190] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Fatty acid synthase (FAS) is a key metabolic enzyme catalyzing the synthesis of long-chain saturated fatty acids. It plays a central role in the production of surfactant in fetal lungs, in the supply of fatty components of milk, and in the conversion and storage of energy in liver and adipose tissue. Remarkably high levels of FAS expression are found in the majority of human epithelial cancers. As the role of FAS in cancer cells remains largely unknown, we have initiated studies to assess the fate of newly synthesized lipids in cancer cells and have estimated the contribution of FAS to the synthesis of specific lipid classes by treating the cells with small interfering RNAs targeting FAS. Here, we show that in cancer cells FAS plays a major role in the synthesis of phospholipids partitioning into detergent-resistant membrane microdomains. These are raft-aggregates implicated in key cellular processes including signal transduction, intracellular trafficking, cell polarization, and cell migration. These findings reveal a novel role for FAS, provide important new insights into the otherwise poorly understood mechanisms underlying the control of lipid composition of membrane microdomains, and point to a link between FAS overexpression and dysregulation of membrane composition and functioning in tumor cells.
Collapse
|
21
|
Timmermans L, Hekster C. [Urological conditions in patients confined to an institution. A retrospective study in a psychiatric hospital]. ACTA UROLOGICA BELGICA 2002; 68:16-9. [PMID: 11565483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
|
22
|
Zimmer W, Wesche M, Timmermans L. Identification and isolation of the indole-3-pyruvate decarboxylase gene from Azospirillum brasilense Sp7: sequencing and functional analysis of the gene locus. Curr Microbiol 1998; 36:327-31. [PMID: 9608743 DOI: 10.1007/s002849900317] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The root-associated bacterium Azospirillum brasilense Sp7 produces the growth-stimulating phytohormone indole-3-acetic acid (= IAA) via the indole-3-pyruvate pathway. The DNA region containing ipdC, the structural gene for indole-3-pyruvate decarboxylase, was identified in a cosmid gene library of strain Sp7 by hybridization and has been sequenced. Upstream of the gene, two other ORF homologous to gltX and cysS were sequenced that are transcribed in the opposite direction. A functional analysis of the cloned ipdC region has been performed. To test the expression of the gene, a lacZ-Km cartridge was introduced into the gene. By this construct, tryptophan-dependent stimulation of gene expression in A. brasilense Sp7 was observed. Evidences for the existence of another copy of the ipdC gene in the Azospirillum genome are also reported.
Collapse
|
23
|
Timmermans L. [Methodology of penile isotope imaging. Evaluation]. ACTA UROLOGICA BELGICA 1998; 66:13-17. [PMID: 9611353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
AIMS Duplex ultrasonography and pulsed doppler analysis or dynamic infusion cavernosometry and cavernosography are used for functional evaluation of penile arterial or venous dynamics during a pharmacological erection. The accuracy of the echographic investigations is correlated to the investigator experience. Cavernosometry and cavernosography are more invasive technique than the radioisotope erection penogram, which is a reproductive and reliable test. MATERIAL AND METHODS We investigate 60 patients. Neurological, psychological and endocrinological etiology are excluded. The technique is described: thyroid is blocked by potassium perchlorate, bloodpool is labelled with Tc99m, a dynamic study is performed over 60 mn with intracavernous injection of PGE1 5g or Papaverine 30 mg at T10mn, ROIS are defined by computer processing, a phalogram curve is provided. RESULTS This noninvasive test sorts out arteriogenic, venogenic and psychogenic impotence by a qualitative curve analysis. The quantitative parameters depending on numerous time consuming variables have proved to be of poor clinical use and non significant. We objectivate 20 psychogenic impotence, 27 arteriogenic impotence, 7 venous leakage and 6 mixed (arteriogenic and venogenic) impotence. Statistic evaluation of arteriogenic lesions comparative by doppler technique reveals a sensitivity of 83% and a specificity of 87%. The advantages of the test are; ambulatory, objective, noninvasive and reliable investigation. In the same time, "qualitative" data evaluates the response to a pharmacological induced erection. CONCLUSIONS The radioisotope erection penogram is a noninvasive, reproductive and reliable screening test for vasculogenic impotence.
Collapse
|
24
|
Marotta J, Dardenne B, Beauduin M, Darimont M, Timmermans L, Schmitz A. [Liposarcoma of the spermatic cord]. ACTA UROLOGICA BELGICA 1996; 64:37-41. [PMID: 8984855] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The liposarcoma is mainly located in the retroperitoneum and rarely involves the spermatic cord. Dissemination occurs more often via haematogenous way than by lymphatic way. The incidence of local recurrence is higher than distant metastases. The treatment of choice is the wide excision. Adjuvant radiotherapy is recommended in the well differentiated and myxoid type of tumors if the local control during excision is not complete or wide enough. Benefit of chemotherapy is still controversial and limited. Case report of a stage 1 liposarcoma of the spermatic cord, four years after excision of a large lipoma during a hernia repair. The treatment consisted in radical excision of this liposarcoma without any adjuvant therapy. Follow-up of 30 months without recurrence.
Collapse
|
25
|
Nagels G, Mariön P, Pickut BA, Timmermans L, De Deyn PP. Actigraphic evaluation of handedness. ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY 1996; 101:226-32. [PMID: 8647035 DOI: 10.1016/0924-980x(96)95566-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The utility of an objective evaluation of motor activity, actigraphy, was examined in the evaluation of handedness. Hand preference was assessed in a homogeneous group of 190 young volunteers using the Edinburgh Inventory (EI). The EI distribution obtained in the population studied was comparable with distributions cited in the literature. Simultaneous actigraphic recordings from both wrists were made in 58 of these subjects for 20 h, starting at 1000 h, using an epoch length of 4 s. Care was taken to include comparable numbers of right- and left-handers (based on EI score) in this subgroup. Two actigraphic parameters were defined. One of these, the Activity Index (AI[x]), is a measure of the difference in total motor activity between right and left wrist. The other, Movement Index (MIy[x]) is a measure of the difference in movement pattern. AI[x] showed a moderate but significant correlation with EI (r = 0.36, P < 0.005). The correlation between MIy[x] and EI was high (r = 0.65, P < 0.0001). Rebinning of the data into 60 s epochs decreased the degree of linear correlation between MIy[x] and EI. We conclude, in contrast to a previous study, that actigraphy can be used to discriminate between dominant and non-dominant hands; that the difference in movement pattern between right and left hand is larger than the difference in total motor activity; and that epoch lengths shorter than the conventional 60 s are more sensitive for this kind of discrimination.
Collapse
|