The Hippo pathway is a highly conserved signalling route involved in organ size regulation. The final effectors of this pathway are two transcriptional coactivators, yes-associated protein (YAP)... Show moreThe Hippo pathway is a highly conserved signalling route involved in organ size regulation. The final effectors of this pathway are two transcriptional coactivators, yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (WWTR1 or TAZ). Previously, we showed aberrant activation of the Hippo pathway in autosomal-dominant polycystic kidney disease (ADPKD), suggesting that YAP/TAZ might play a role in disease progression. Using antisense oligonucleotides (ASOs) in a mouse model for ADPKD, we efficiently down-regulatedYaplevels in the kidneys. However, we did not see any effect on cyst formation or growth. Moreover, the expression of YAP/TAZ downstream targets was not changed, while WNT and TGF-beta pathways' downstream targetsMyc,Acta2andVimwere more expressed afterYapknockdown. Overall, our data indicate that reducing YAP levels is not a viable strategy to modulate PKD progression. Show less
Polycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most... Show morePolycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most interventions still focus on alleviating PKD-associated symptoms. The mechanistic complexity of the disease, as well as the lack of functional in vitro assays for compound testing, has made drug discovery for PKD challenging. To identify modulators of PKD, Pkd1–/– kidney tubule epithelial cells were applied to a scalable and automated 3D cyst culture model for compound screening, followed by phenotypic profiling to determine compound efficacy. We used this screening platform to screen a library of 273 kinase inhibitors to probe various signaling pathways involved in cyst growth. We show that inhibition of several targets, including aurora kinase, CDK, Chk, IGF-1R, Syk, and mTOR, but, surprisingly, not PI3K, prevented forskolin-induced cyst swelling. Additionally, we show that multiparametric phenotypic classification discriminated potentially undesirable (i.e., cytotoxic) compounds from molecules inducing the desired phenotypic change, greatly facilitating hit selection and validation. Our findings show that a pathophysiologically relevant 3D cyst culture model of PKD coupled to phenotypic profiling can be used to identify potentially therapeutic compounds and predict and validate molecular targets for PKD. Show less
Polycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most... Show morePolycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most interventions still focus on alleviating PKD-associated symptoms. The mechanistic complexity of the disease, as well as the lack of functional in vitro assays for compound testing, has made drug discovery for PKD challenging. To identify modulators of PKD, Pkd1–/– kidney tubule epithelial cells were applied to a scalable and automated 3D cyst culture model for compound screening, followed by phenotypic profiling to determine compound efficacy. We used this screening platform to screen a library of 273 kinase inhibitors to probe various signaling pathways involved in cyst growth. We show that inhibition of several targets, including aurora kinase, CDK, Chk, IGF-1R, Syk, and mTOR, but, surprisingly, not PI3K, prevented forskolin-induced cyst swelling. Additionally, we show that multiparametric phenotypic classification discriminated potentially undesirable (i.e., cytotoxic) compounds from molecules inducing the desired phenotypic change, greatly facilitating hit selection and validation. Our findings show that a pathophysiologically relevant 3D cyst culture model of PKD coupled to phenotypic profiling can be used to identify potentially therapeutic compounds and predict and validate molecular targets for PKD. Show less
Polycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most... Show morePolycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most interventions still focus on alleviating PKD-associated symptoms. The mechanistic complexity of the disease, as well as the lack of functional in vitro assays for compound testing, has made drug discovery for PKD challenging. To identify modulators of PKD, Pkd1–/– kidney tubule epithelial cells were applied to a scalable and automated 3D cyst culture model for compound screening, followed by phenotypic profiling to determine compound efficacy. We used this screening platform to screen a library of 273 kinase inhibitors to probe various signaling pathways involved in cyst growth. We show that inhibition of several targets, including aurora kinase, CDK, Chk, IGF-1R, Syk, and mTOR, but, surprisingly, not PI3K, prevented forskolin-induced cyst swelling. Additionally, we show that multiparametric phenotypic classification discriminated potentially undesirable (i.e., cytotoxic) compounds from molecules inducing the desired phenotypic change, greatly facilitating hit selection and validation. Our findings show that a pathophysiologically relevant 3D cyst culture model of PKD coupled to phenotypic profiling can be used to identify potentially therapeutic compounds and predict and validate molecular targets for PKD. Show less
Polycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most... Show morePolycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most interventions still focus on alleviating PKD-associated symptoms. The mechanistic complexity of the disease, as well as the lack of functional in vitro assays for compound testing, has made drug discovery for PKD challenging. To identify modulators of PKD, Pkd1–/– kidney tubule epithelial cells were applied to a scalable and automated 3D cyst culture model for compound screening, followed by phenotypic profiling to determine compound efficacy. We used this screening platform to screen a library of 273 kinase inhibitors to probe various signaling pathways involved in cyst growth. We show that inhibition of several targets, including aurora kinase, CDK, Chk, IGF-1R, Syk, and mTOR, but, surprisingly, not PI3K, prevented forskolin-induced cyst swelling. Additionally, we show that multiparametric phenotypic classification discriminated potentially undesirable (i.e., cytotoxic) compounds from molecules inducing the desired phenotypic change, greatly facilitating hit selection and validation. Our findings show that a pathophysiologically relevant 3D cyst culture model of PKD coupled to phenotypic profiling can be used to identify potentially therapeutic compounds and predict and validate molecular targets for PKD. Show less
Polycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most... Show morePolycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most interventions still focus on alleviating PKD-associated symptoms. The mechanistic complexity of the disease, as well as the lack of functional in vitro assays for compound testing, has made drug discovery for PKD challenging. To identify modulators of PKD, Pkd1–/– kidney tubule epithelial cells were applied to a scalable and automated 3D cyst culture model for compound screening, followed by phenotypic profiling to determine compound efficacy. We used this screening platform to screen a library of 273 kinase inhibitors to probe various signaling pathways involved in cyst growth. We show that inhibition of several targets, including aurora kinase, CDK, Chk, IGF-1R, Syk, and mTOR, but, surprisingly, not PI3K, prevented forskolin-induced cyst swelling. Additionally, we show that multiparametric phenotypic classification discriminated potentially undesirable (i.e., cytotoxic) compounds from molecules inducing the desired phenotypic change, greatly facilitating hit selection and validation. Our findings show that a pathophysiologically relevant 3D cyst culture model of PKD coupled to phenotypic profiling can be used to identify potentially therapeutic compounds and predict and validate molecular targets for PKD. Show less
Polycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most... Show morePolycystic kidney disease (PKD) is a prevalent disorder characterized by renal cysts that lead to kidney failure. Various signaling pathways have been targeted to stop disease progression, but most interventions still focus on alleviating PKD-associated symptoms. The mechanistic complexity of the disease, as well as the lack of functional in vitro assays for compound testing, has made drug discovery for PKD challenging. To identify modulators of PKD, Pkd1–/– kidney tubule epithelial cells were applied to a scalable and automated 3D cyst culture model for compound screening, followed by phenotypic profiling to determine compound efficacy. We used this screening platform to screen a library of 273 kinase inhibitors to probe various signaling pathways involved in cyst growth. We show that inhibition of several targets, including aurora kinase, CDK, Chk, IGF-1R, Syk, and mTOR, but, surprisingly, not PI3K, prevented forskolin-induced cyst swelling. Additionally, we show that multiparametric phenotypic classification discriminated potentially undesirable (i.e., cytotoxic) compounds from molecules inducing the desired phenotypic change, greatly facilitating hit selection and validation. Our findings show that a pathophysiologically relevant 3D cyst culture model of PKD coupled to phenotypic profiling can be used to identify potentially therapeutic compounds and predict and validate molecular targets for PKD. Show less
Mosaicism involving a normal cell line and an unbalanced autosomal translocation are rare. In this study we present three new cases with such a mosaicism, which were detected by Single Nucleotide... Show moreMosaicism involving a normal cell line and an unbalanced autosomal translocation are rare. In this study we present three new cases with such a mosaicism, which were detected by Single Nucleotide Polymorphism (SNP) array analysis in our routine diagnostic setting. These cases were further characterized using Fluorescence in situ Hybridisation (FISH) analysis and conventional karyotyping. The first case is a mentally retarded male who carries an unbalanced translocation in 87% of his cells. The phenotypically normal mother carries the balanced form of the translocation in all her cells. The second case is a phenotypically normal female who has an unbalanced translocation in 52% of her cells. The inheritance could not be determined. The third case is a female referred for Rubinsteine-Taybi syndrome who carries an unbalanced translocation in 60% of her cells. Both parents of this case showed a normal karyotype. The mechanisms that might be responsible for these mosaic karyotypes are discussed. Furthermore, we demonstrate that high-resolution whole-genome SNP array is a powerful tool to reveal cryptic unbalanced translocations and mosaicisms, including the more rare cases. (C) 2011 Elsevier Masson SAS. All rights reserved. Show less
Lemmers, R.J.L.F.; Vliet, P.J. van der; Klooster, R.; Sacconi, S.; Camano, P.; Dauwerse, J.G.; ... ; Maarel, S.M. van der 2010
Facioscapulohumeral muscular dystrophy (FSHD) is a common form of muscular dystrophy in adults that is foremost characterized by progressive wasting of muscles in the upper body. FSHD is associated... Show moreFacioscapulohumeral muscular dystrophy (FSHD) is a common form of muscular dystrophy in adults that is foremost characterized by progressive wasting of muscles in the upper body. FSHD is associated with contraction of D4Z4 macrosatellite repeats on chromosome 4q35, but this contraction is pathogenic only in certain "permissive" chromosomal backgrounds. Here, we show that FSHD patients carry specific single-nucleotide polymorphisms in the chromosomal region distal to the last D4Z4 repeat. This FSHD-predisposing configuration creates a canonical polyadenylation signal for transcripts derived from DUX4, a double homeobox gene of unknown function that straddles the last repeat unit and the adjacent sequence. Transfection studies revealed that DUX4 transcripts are efficiently polyadenylated and are more stable when expressed from permissive chromosomes. These findings suggest that FSHD arises through a toxic gain of function attributable to the stabilized distal DUX4 transcript. Show less
We have characterized a de novo complex rearrangement of the long arm of chromosome 7 in a female patient with moderate mental retardation (MR), anxiety disorder, and autistic features. G-banding... Show moreWe have characterized a de novo complex rearrangement of the long arm of chromosome 7 in a female patient with moderate mental retardation (MR), anxiety disorder, and autistic features. G-banding suggested a de novo paracentric inversion 46,XX,inv-(7) (q31.3q34). However, SNP-array analysis, showed a +/-10 Mb, 7q21.11-q21.3 deletion in the paternal chromosome. Subsequent FISH analysis with BAC/PAC clones in the 7q21-q35 region confirmed this deletion. However, the expected paracentric inversion turned out to be an intra-chromosomal insertion of the 7q31.31-q35 fragment into band 7q21.3, disrupting the predicted gene C7orf58 in band 7q31.31. Seven other patients have been previously reported with a deletion of 7q21.1-q21.3. Although there is an overlap in phenotype between our patient and these patients, none of them has been described with anxiety disorder and/or autistic features. Therefore we suggest that disruption of the C7orf58 gene might contribute to the anxiety disorder, and autistic features in our patient. (C) 2010 Wiley-Liss, Inc. Show less
We have characterized a de novo complex rearrangement of the long arm of chromosome 7 in a female patient with moderate mental retardation (MR), anxiety disorder, and autistic features. G-banding... Show moreWe have characterized a de novo complex rearrangement of the long arm of chromosome 7 in a female patient with moderate mental retardation (MR), anxiety disorder, and autistic features. G-banding suggested a de novo paracentric inversion 46,XX,inv(7)(q31.3q34). However, SNP-array analysis, showed a +/-10 Mb, 7q21.11-q21.3 deletion in the paternal chromosome. Subsequent FISH analysis with BAC/PAC clones in the 7q21-q35 region confirmed this deletion. However, the expected paracentric inversion turned out to be an intra-chromosomal insertion of the 7q31.31-q35 fragment into band 7q21.3, disrupting the predicted gene C7orf58 in band 7q31.31. Seven other patients have been previously reported with a deletion of 7q21.1-q21.3. Although there is an overlap in phenotype between our patient and these patients, none of them has been described with anxiety disorder and/or autistic features. Therefore we suggest that disruption of the C7orf58 gene might contribute to the anxiety disorder, and autistic features in our patient. Show less
Lemmers, R.J.L.F.; Vliet, P.J. van der; Klooster, R.; Sacconi, S.; Camano, P.; Dauwerse, J.G.; ... ; Maarel, S.M. van der 2010
Facioscapulohumeral muscular dystrophy (FSHD) is a common form of muscular dystrophy in adults that is foremost characterized by progressive wasting of muscles in the upper body. FSHD is associated... Show moreFacioscapulohumeral muscular dystrophy (FSHD) is a common form of muscular dystrophy in adults that is foremost characterized by progressive wasting of muscles in the upper body. FSHD is associated with contraction of D4Z4 macrosatellite repeats on chromosome 4q35, but this contraction is pathogenic only in certain "permissive" chromosomal backgrounds. Here, we show that FSHD patients carry specific single-nucleotide polymorphisms in the chromosomal region distal to the last D4Z4 repeat. This FSHD-predisposing configuration creates a canonical polyadenylation signal for transcripts derived from DUX4, a double homeobox gene of unknown function that straddles the last repeat unit and the adjacent sequence. Transfection studies revealed that DUX4 transcripts are efficiently polyadenylated and are more stable when expressed from permissive chromosomes. These findings suggest that FSHD arises through a toxic gain of function attributable to the stabilized distal DUX4 transcript. Show less
