Background and ObjectivesThe Levodopa in EArly Parkinson's Disease (LEAP) study enabled us to conduct post hoc analyses concerning the effects of levodopa in patients with early Parkinson disease... Show moreBackground and ObjectivesThe Levodopa in EArly Parkinson's Disease (LEAP) study enabled us to conduct post hoc analyses concerning the effects of levodopa in patients with early Parkinson disease.MethodsThe LEAP study was a double-blind, placebo-controlled, randomized, delayed-start trial in which patients with early Parkinson disease were randomized to receive levodopa/carbidopa 300/75 mg daily for 80 weeks (early-start group) or to placebo for 40 weeks followed by levodopa/carbidopa 300/75 mg daily for 40 weeks (delayed-start group). We analyzed the effect of levodopa with the Unified Parkinson's Disease Rating Scale on bradykinesia, rigidity, and tremor. At week 80, participants answered 3 questions regarding motor response fluctuations.ResultsA total of 222 patients were randomized to the early-start group (mean ± SD age at baseline 64.8 ± 8.7 years; 71% male) and 223 to the delayed-start group (mean ± SD age at baseline 65.5 ± 8.8 years; 69% male). The difference between the early- and delayed-start groups in mean change from baseline to week 4, expressed as Hedges g effect size, was −0.33 for bradykinesia, −0.29 for rigidity, and −0.25 for tremor (for all symptoms indicating a small effect in favor of the early-start group); from baseline to week 22, respectively, −0.49, −0.36, and −0.44 (small to medium effect); and from baseline to week 40, respectively, −0.32, −0.19, and −0.27 (small effect). At 80 weeks, fewer patients in the early-start group (46 of 205 patients, 23%) experienced motor response fluctuations than patients in the delayed-start group (81 of 211, 38%; p < 0.01).DiscussionIn patients with early Parkinson disease, levodopa improves bradykinesia, rigidity, and tremor to the same order of magnitude. For all 3 symptoms, effects were larger at 22 weeks compared with 4 weeks. At 80 weeks, there were fewer patients with motor response fluctuations in the group that had started levodopa earlier. Show less
Verschuur, C.V.M.; Suwijn, S.R.; Haan, R.J. de; Boel, J.A.; Post, B.; Bloem, B.R.; ... ; Bie, R.M.A. de 2022
Background: In the Levodopa in EArly Parkinson's disease (LEAP) study, 445 patients were randomized to levodopa/carbidopa 100/25 mg three times per day for 80 weeks (early-start) or placebo for 40... Show moreBackground: In the Levodopa in EArly Parkinson's disease (LEAP) study, 445 patients were randomized to levodopa/carbidopa 100/25 mg three times per day for 80 weeks (early-start) or placebo for 40 weeks followed by levodopa/carbidopa 100/25 mg three times per day for 40 weeks (delayed-start). Objective: This paper reports the results of the economic evaluation performed alongside the LEAP-study.Methods: Early-start treatment was evaluated versus delayed-start treatment, in which the cost-effectiveness analysis (CEA) and the cost-utility analysis (CUA) were performed from the societal perspective, including health care costs among providers, non-reimbursable out-of-pocket expenses of patients, employer costs of sick leave, and lowered productivity while at work. The outcome measure for the CEA was the extra cost per unit decrease on the Unified Parkinson's Disease Rating Scale 80 weeks after baseline. The outcome measure for the CUA was the extra costs per additional quality adjusted life year (QALY) during follow-up. Results: 212 patients in the early-start and 219 patients in the delayed-start group reported use of health care resources. With savings of D 59 per patient (BCa 95% CI: -829, 788) in the early-start compared to the delayed-start group, societal costs were balanced. The early-start group showed a mean of 1.30 QALYs (BCa 95% CI: 1.26, 1.33) versus 1.30 QALYs (BCa 95% CI: 1.27, 1.33) for the delayed-start group. Because of this negligible difference, incremental cost-effectiveness and cost-utility ratios were not calculated. Conclusion: From an economic point of view, this study suggests that early treatment with levodopa is not more expensive than delayed treatment with levodopa. Show less
Background The most common genetic risk factor for Parkinson's disease known is a damaging variant in theGBA1gene. The entireGBA1gene has rarely been studied in a large cohort from a single... Show moreBackground The most common genetic risk factor for Parkinson's disease known is a damaging variant in theGBA1gene. The entireGBA1gene has rarely been studied in a large cohort from a single population. The objective of this study was to assess the entireGBA1gene in Parkinson's disease from a single large population. Methods TheGBA1gene was assessed in 3402 Dutch Parkinson's disease patients using next-generation sequencing. Frequencies were compared with Dutch controls (n = 655). Family history of Parkinson's disease was compared in carriers and noncarriers. Results Fifteen percent of patients had aGBA1nonsynonymous variant (including missense, frameshift, and recombinant alleles), compared with 6.4% of controls (OR, 2.6;P < 0.001). Eighteen novel variants were detected. Variants previously associated with Gaucher's disease were identified in 5.0% of patients compared with 1.5% of controls (OR, 3.4;P < 0.001). The rarely reported complex allele p.D140H + p.E326K appears to likely be a Dutch founder variant, found in 2.4% of patients and 0.9% of controls (OR, 2.7;P= 0.012). The number of first-degree relatives (excluding children) with Parkinson's disease was higher in p.D140H + p.E326K carriers (5.6%, 21 of 376) compared with p.E326K carriers (2.9%, 29 of 1014); OR, 2.0;P= 0.022, suggestive of a dose effect for differentGBA1variants. Conclusions Dutch Parkinson's disease patients display one of the largest frequencies ofGBA1variants reported so far, consisting in large part of the mild p.E326K variant and the more severe Dutch p.D140H + p.E326K founder allele. (c) 2020 International Parkinson and Movement Disorder Society Show less
Verschuur, C.V.M.; Suwijn, S.R.; Boel, J.A.; Post, B.; Bloem, B.R.; Hilten, J.J. van; ... ; LEAP Study Grp 2019
BACKGROUND The transforming growth factor (TGF)-β superfamily comprises cytokines such as TGF-β and Bone Morphogenetic Proteins (BMPs), which have a critical role in a multitude of biological... Show moreBACKGROUND The transforming growth factor (TGF)-β superfamily comprises cytokines such as TGF-β and Bone Morphogenetic Proteins (BMPs), which have a critical role in a multitude of biological processes. In breast cancer, high levels of TGF-β are associated with poor outcome, whereas inhibition of TGF-β-signaling reduces metastasis. In contrast, BMP-7 inhibits bone metastasis of breast cancer cells. METHODS In this study, we investigated the effect of BMP-7 on TGF-β-induced invasion in a 3 dimensional invasion assay. RESULTS BMP-7 inhibited TGF-β-induced invasion of the metastatic breast cancer cell line MCF10CA1a, but not of its premalignant precursor MCF10AT in a spheroid invasion model. The inhibitory effect appears to be specific for BMP-7, as its closest homolog, BMP-6, did not alter the invasion of MCF10CA1a spheroids. To elucidate the mechanism by which BMP-7 inhibits TGF-β-induced invasion, we analyzed invasion-related genes. BMP-7 inhibited TGF-β-induced expression of integrin α(v)β(3) in the spheroids. Moreover, targeting of integrins by a chemical inhibitor or knockdown of integrin β(3) negatively affected TGF-β-induced invasion. On the other hand, overexpression of integrin β(3) counteracted the inhibitory effect of BMP7 on TGF-β-induced invasion. CONCLUSION Thus, BMP-7 may exert anti-invasive actions by inhibiting TGF-β-induced expression of integrin β(3). Show less
Naber, H.P.H.; Wiercinska, E.; Pardali, E.; Laar, T. van; Nirmala, E.; Sundqvist, A.; ... ; Dijke, P. ten 2012
TGF-β has opposing roles in breast cancer progression by acting as a tumor suppressor in the initial phase, but stimulating invasion and metastasis at later stage(1,2). Moreover, TGF-β is... Show moreTGF-β has opposing roles in breast cancer progression by acting as a tumor suppressor in the initial phase, but stimulating invasion and metastasis at later stage(1,2). Moreover, TGF-β is frequently overexpressed in breast cancer and its expression correlates with poor prognosis and metastasis (3,4). The mechanisms by which TGF-β induces invasion are not well understood. TGF-β elicits its cellular responses via TGF-β type II (TβRII) and type I (TβRI) receptors. Upon TGF-β-induced heteromeric complex formation, TβRII phosphorylates the TβRI. The activated TβRI initiates its intracellular canonical signaling pathway by phosphorylating receptor Smads (R-Smads), i.e. Smad2 and Smad3. These activated R-Smads form heteromeric complexes with Smad4, which accumulate in the nucleus and regulate the transcription of target genes(5). In addition to the previously described Smad pathway, receptor activation results in activation of several other non-Smad signaling pathways, for example Mitogen Activated Protein Kinase (MAPK) pathways(6). To study the role of TGF-β in different stages of breast cancer, we made use of the MCF10A cell system. This system consists of spontaneously immortalized MCF10A1 (M1) breast epithelial cells(7), the H-RAS transformed M1-derivative MCF10AneoT (M2), which produces premalignant lesions in mice(8), and the M2-derivative MCF10CA1a (M4), which was established from M2 xenografts and forms high grade carcinomas with the ability to metastasize to the lung(9). This MCF10A series offers the possibility to study the responses of cells with different grades of malignancy that are not biased by a different genetic background. For the analysis of TGF-β-induced invasion, we generated homotypic MCF10A spheroid cell cultures embedded in a 3D collagen matrix in vitro (Fig 1). Such models closely resemble human tumors in vivo by establishing a gradient of oxygen and nutrients, resulting in active and invasive cells on the outside and quiescent or even necrotic cells in the inside of the spheroid(10). Spheroid based assays have also been shown to better recapitulate drug resistance than monolayer cultures(11). This MCF10 3D model system allowed us to investigate the impact of TGF-β signaling on the invasive properties of breast cells in different stages of malignancy. Show less
Zhou, F.F.; Gong, K.; Laar, T. van; Gong, Y.D.; Zhang, L. 2011
Glycogen synthase kinase 3 beta (GSK3 beta) regulates diverse physiological processes, including metabolism, development, oncogenesis, and neuroprotection. GSK3 beta kinase activity has been... Show moreGlycogen synthase kinase 3 beta (GSK3 beta) regulates diverse physiological processes, including metabolism, development, oncogenesis, and neuroprotection. GSK3 beta kinase activity has been reported to be critical for various types of cancer cells, but the mechanism has remained elusive. In this study we examine the mechanism by which GSK3 beta regulates the survival of leukemia cells. We demonstrate that upon GSK3 beta kinase inhibition different types of leukemia cells show severe proliferation defects as a result of apoptosis. The transcription factor c-Myb is found to be the main target of GSK3 beta inhibition in cell survival. GSK3 beta inactivation reduces the expression of c-Myb by promoting its ubiquitination-mediated degradation, thereby inhibiting the expression of c-Myb-dependent antiapoptotic genes Bcl2 and survivin. Coimmunoprecipitation, reporter assays, chromatin immunoprecipitation, and knockdown studies show that c-Myb needs to interact and cooperate with transcription factor LEF-1 in the activation of Bcl2 and survivin and that both transcription factors are required for cell survival. These data reveal an as-yet-unknown mechanism by which GSK3 beta controls cell survival. Show less
Zhou, F.F.; Gong, K.; Laar, T. van; Gong, Y.D.; Zhang, L. 2011
Amyloid precursor protein (APP), a key protein in pathogenesis of Alzheimer's disease (AD), is a type I transmembrane protein which can be cleaved by beta- and gamma-secretase to release the... Show moreAmyloid precursor protein (APP), a key protein in pathogenesis of Alzheimer's disease (AD), is a type I transmembrane protein which can be cleaved by beta- and gamma-secretase to release the amyloidogenic beta-amyloid peptides (A beta) and the APP intracellular domain (AICD). While A beta has been widely believed to initiate pathogenic cascades culminating AD, the physiological functions and regulations of AICD remain elusive. In present study, endogenous AICD was demonstrated to be increased by canonical Wnt signal. Instead of due to gamma-secretase activity, enhanced AICD expression was found due to the increased protein stability by Wnt/beta-catenin. beta-Catenin was demonstrated to be an associating partner of AICD, capable of promoting AICD mediated transcriptional activity. Investigation by AICD mutants proved that Fe65, a previously identified AICD binding partner, is not involved in this regulation. Taken together, our results suggest that AICD is stabilized and the AICD mediated transcriptional activity is promoted by canonical Wnt/beta-catenin signaling independent of Fe65. (C) 2011 Elsevier Inc. All rights reserved. Show less
Verbaan, D.; Jeukens-Visser, M.; Laar, T. van; Rooden, S.M. van; Zwet, E.W. van; Marinus, J.; Hilten, J.J. van 2011
The SCOPA-Cognition is a reliable and valid test to evaluate cognitive functioning in Parkinson's disease and is widely used in clinical and research settings. Recently, the Movement Disorder... Show moreThe SCOPA-Cognition is a reliable and valid test to evaluate cognitive functioning in Parkinson's disease and is widely used in clinical and research settings. Recently, the Movement Disorder Society introduced criteria for Parkinson's disease dementia. The objective of the present study was to use these criteria to determine SCOPA-Cognition cutoffs for maximum accuracy, screening, and diagnosing of Parkinson's disease dementia. A total of 282 patients with Parkinson's disease were assessed with the SCOPA-Cognition and the Movement Disorder Society's Parkinson's disease dementia criteria. From the 275 patients with a complete assessment of the dementia criteria, 12% (n = 32) fulfilled the criteria. Data from 268 patients with complete assessments of both the dementia criteria and the SCOPA-Cognition were used to determine cutoffs for maximum accuracy, screening, and diagnosing of Parkinson's disease dementia. The area under the curve was 0.91 (95% confidence interval, 0.85-0.97), showing a strong association between the dementia criteria and the SCOPA-Cognition. The cutoff for maximum accuracy was 22/23, based on the highest sum of sensitivity (0.80) and specificity (0.87), with positive and negative predictive values of 0.43 and 0.97, respectively. The optimal screening cutoff was 24/25, and the optimal diagnostic cutoff was 17/18. Using the recently published Parkinson's disease dementia criteria as a reference, the current study presents SCOPA-Cognition cutoffs for maximum accuracy, screening, and diagnosing of Parkinson's disease dementia. The availability of SCOPA-Cognition cutoffs for Parkinson's disease dementia may contribute to the scale's usefulness and promote its further use in both clinical and research settings. Show less
Zhou, F.F.; Laar, T. van; Huang, H.Z.; Zhang, L. 2011
Amyloid beta (Aβ) precursor protein (APP) is a key protein in the pathogenesis of Alzheimer's disease (AD). Both APP and its paralogue APLP1 (amyloid beta precursor-like protein 1) have multiple... Show moreAmyloid beta (Aβ) precursor protein (APP) is a key protein in the pathogenesis of Alzheimer's disease (AD). Both APP and its paralogue APLP1 (amyloid beta precursor-like protein 1) have multiple functions in cell adhesion and proliferation. Previously it was thought that autophagy is a novel beta-amyloid peptide (Aβ)-generating pathway activated in AD. However, the protein proteolysis of APLP1 is still largely unknown. The present study shows that APLP1 is rapidly degraded in neuronal cells in response to stresses, such as proteasome inhibition. Activation of the endoplasmic reticulum (ER) stress by proteasome inhibitors induces autophagy, causing reduction of mature APLP1/APP. Blocking autophagy or JNK stress kinase rescues the protein expression for both APP and APLP1. Therefore, our results suggest that APP/APLP1 is degraded through autophagy and the APLP1 proteolysis is mainly mediated by autophagy-lysosome pathway. Show less
Zhang, L.; Zhou, F.F.; Laar, T. van; Zhang, J.; Dam, H. van; Dijke, P. ten 2011
The canonical Wnt pathway plays an important role in the regulation of cell proliferation and differentiation. Activation of this signaling pathway causes disruption of the Axin/adenomatous... Show moreThe canonical Wnt pathway plays an important role in the regulation of cell proliferation and differentiation. Activation of this signaling pathway causes disruption of the Axin/adenomatous polyposis coli/glycogen synthase kinase 3 beta complex, resulting in stabilization of beta-catenin and its association with lymphoid enhancer factor/T-cell factor in the nucleus. Here, we identify Fas-associated factor 1 (FAF1) as a negative regulator of Wnt/beta-catenin signaling. We found overexpression of FAF1 to strongly inhibit Wnt-induced transcriptional reporter activity and to counteract Wnt-induced beta-catenin accumulation. Moreover, knockdown of FAF1 resulted in an increase in beta-catenin levels and in activation of Wnt/beta-catenin-induced transcription. FAF1 was found to interact with beta-catenin upon inhibition of proteasome. Ectopic expression of FAF1 promoted beta-catenin degradation by enhancing its polyubiquitination. Functional studies in C2C12 myoblasts and KS483 preosteoblastic cells showed that FAF1 depletion resulted in activation of endogenous Wnt-induced genes and enhanced osteoblast differentiation, whereas FAF1 overexpression had the opposite effect. These results identify FAF1 as a novel inhibitory factor of canonical Wnt signaling pathway. Show less
