BackgroundThe focal form of CHI is caused by an autosomal recessive pathogenic variant affecting ... more BackgroundThe focal form of CHI is caused by an autosomal recessive pathogenic variant affecting the paternal homologue of genes ABCC8 or KCNJ11 and a second somatic event specifically occurring in the affected islet of Langerhans. The approach of this study was to integrate the genetic changes occurring in pancreatic focal lesions of CHI at the genomic and transcriptional level.Research Design and MethodsPatients receiving therapeutic surgery and with proven ABCC8 or KCNJ11 pathogenic variants were selected and analyzed for loss of heterozygosity (LOH), changes in copy number and uniparental disomy (UPD) on the short am of chromosome 11 by molecular microarray analysis and methylation-specific MLPA. Gene expression was analyzed by RT-PCR and Massive Analysis of cDNA Ends (MACE).ResultsBoth genes, ABCC8 and KCNJ11, are located in proximity to the Beckwith-Wiedemann (BWS) imprinting control region on chromosome 11p15. Somatic paternal uniparental isodisomy (UPD) at chromosome 11p was...
Cutis marmorata telangiectatica congenita (CMTC) is characterized by coarse-meshed capillary malf... more Cutis marmorata telangiectatica congenita (CMTC) is characterized by coarse-meshed capillary malformations arranged in asymmetrically distributed patches. The disorder may be associated with hyper- or hypoplastic limbs, syndactyly, cleft palate, and glaucoma. Because the disease usually occurs sporadically, the concept of a lethal mutation surviving by mosaicism was proposed about 30 years ago. Here we describe three children with CMTC due to a postzygotic GNA11 mutation c547C > T (p.Arg183Cys), documented in saliva (patient 1) or lesional cutaneous tissue (patients 2 and 3). All three individuals had widespread and asymmetric CMTC which was present from birth and became fainter during the first years of life. Variably associated anomalies included glaucoma, choroidal capillary malformation, and body asymmetry. In previous case reports, postzygotic GNA11 mutations were documented in two cases of phacomatosis cesiomarmorata, being characterized by CMTC coexisting with segmental dermal melanocytosis. Moreover, postzygotic GNA11 mutations were noted in two CMTC patients described under the incorrect diagnosis of "nevus vascularis mixtus". Hence, the present cases convincingly support the concept that CMTC can be caused by mosaic GNA11 mutations and thus belongs to the GNA11-Related Capillary Nevus (GNARCAN) spectrum. In two other bona fide cases of CMTC, however, we were unable to find a mutation in GNA11, which may be explained either by our inability to detect a very low percentage of mutant cells or by genetic heterogeneity of the phenotype.
Background/Aim: The aim of this study was to present the long-term course of a patient with nevus... more Background/Aim: The aim of this study was to present the long-term course of a patient with nevus sebaceous syndrome (NSS). Recent genetic studies place the syndrome in the emerging group of so-called RASopathies. The focus of the report is on surgical treatment and morphological and genetic findings of the face and oral cavity. Case Report: A female patient was treated for congenital alterations of facial skin and oral mucosa. The oral lesions were removed repeatedly. Eruption of teeth on the lesion sites was made easier by the measures taken. However, after repeated ablation of the affected gingiva, the periodontal papillomatous epithelium redifferentiated into the same reddish, conspicuous, hyperplastic epithelium. The teeth in the affected region showed noticeable changes in position, surface, and shape. A HRAS mutation was detected only in the regions of altered oral epithelia and not in adjacent soft tissues. Conclusion: Reports on NSS rarely address oral manifestations. The recorded alterations of oral soft and hard tissues in NSS indicate a topographical relationship between the development of oral mucosa and teeth as well as the long-lasting impact of a sporadic mutation on organ development at this site. Epidermal nevi (EN) are mosaic cutaneous developmental disorders (1-6). EN are differentiated according to the predominant epithelial cell types (7). The terminology of nevi refers to the histological components of the lesion (8). If extracutaneous findings are noted in addition to EN in an individual, this constellation is referred to as epidermal nevus syndrome (ENS) (1-6, 9-12). Some authors have used the term 'ENS' to describe a distinct entity, in particular (linear) nevus sebaceous syndrome (NSS) (synonymous: Schimmelpenning-Feuerstein-Mims (SFM) syndrome, Naevus sebaceous Jadassohn (syndrome), Solomon syndrome, and further terms) (1-6, 8, 10). Other authors subsumed a group of cutaneous diseases characterized by nevi and extracutaneous findings under the term 'ENS' (1, 10). Currently, the term 'ENS' is mostly used as an umbrella designation for several syndromes describing diseases with a potentially large variety of physical findings that frequently first attract attention through noticeable alterations in superficial skin layers, in particular nevi (3-5, 8). With this broad sense, ENS also includes nevi that have adnexal differentiation (10). 274 This article is freely accessible online.
Neurofibromatosis type 1 (NF-1) predisposes to juvenile myelomonocytic leukemia (JMML) via loss o... more Neurofibromatosis type 1 (NF-1) predisposes to juvenile myelomonocytic leukemia (JMML) via loss of function of the NF1 tumor suppressor gene and consecutive deregulation of Ras signal transduction. Affected individuals usually carry one defective NF1 allele in the germline; somatic inactivation of the second NF1 allele in hematopoietic cells is associated with transformation to leukemia. We previously demonstrated that a major mechanism for biallelic loss of NF1 function in patients with JMML/NF-1 is mitotic recombination leading to uniparental disomy (UPD) of the 17q chromosome arm (Flotho, 2007; Steinemann, 2010). Using contemporary resequencing and microarray technology, we have now revisited the genetics of NF1 inactivation in JMML. Specifically, we addressed two questions: 1) Are genetic findings in leukemic cells of JMML/NF-1 patients consistent with the clinical diagnosis and the two-hit concept? 2) Does the quintuple-negative (QN) group of JMML (patients without clinical evi...
Background/Aim: Neurofibromatosis type 1 (NF) is an autosomal dominant hereditary disease. The ca... more Background/Aim: Neurofibromatosis type 1 (NF) is an autosomal dominant hereditary disease. The cardinal clinical findings include characteristic skeletal alterations. Difficulties in diagnosis and therapy can arise if an individual has further illnesses. Case Report: This is a case report of a 16-year-old patient affected by NF1. She also suffered from Alagille syndrome and the consequences of fetal alcohol exposure. The patient's facial phenotype showed findings that could be assigned to one or more of the known diseases. The patient was referred for treating a cherubismlike recurrent central giant cell granuloma (CGCG) of the jaw. The patient developed bilateral, multilocular nonossifying fibromas (NOF) of the long bones of the lower extremity. Treatment of the skeletal lesions consisted of local curettage. While NOF regressed after surgery, the CGCG of the jaw remained largely unchanged. Extensive genetic tests confirmed a previously unknown germline mutation in the JAG1 gene, the germline mutation of the NF1 gene, and the somatic mutation in the NF1 gene in the diffuse plexiform neurofibroma, but not in the CGCG. Conclusion: Assigning facial findings to a defined syndrome is ambiguous in many cases and especially difficult in patients who have multiple diseases that can affect the facial phenotype. Surgical therapy should be adapted to the individual findings. Neurofibromatosis type 1 (NF1) is an autosomal dominant inherited disorder (1). The disease has a high penetrance (about 100%). However, the phenotype is extremely variable (2). The NF1 gene is located on chromosome 17q11.2 (3, 4). NF1 is a tumor suppressor gene syndrome (5) and the most common monogenetic disease predisposing to cancer (1). NF1 is primarily characterized by multiple skin tumors. The tumors are of neurogenic origin termed neurofibroma. Somatic mutations of NF1 gene in neurofibroma arise in Schwann cells or precursors of Schwann cells. Since Schwann cells originate from the neural crest, NF1 is rated among the diseases that are characterized by mutations in neural crest cells (6). The frequent and numerous neoplasms of NF1 patients arise primarily from the connective soft tissues. Genetic studies show that many of the different neoplasms arising in NF1 patients meet the criteria of somatic allelic loss of NF1 gene according to Knudson's two-hit hypothesis of tumor development (7). However, the unusual variety of symptoms and findings in NF1 patients go far beyond the spectrum of neoplastic lesions (1). Most cases are diagnosed by clinical examination (Table I). Diagnosis and treatment of NF1 patients can be made more difficult if other diseases develop in the same individual and 1711 This article is freely accessible online.
Article type : Letter to the Editor Detection of a multi-lineage mosaic NRAS mutation c.181C>A (p... more Article type : Letter to the Editor Detection of a multi-lineage mosaic NRAS mutation c.181C>A (p.Gln61Lys) in an individual with a complex congenital nevus syndrome
Results of surgery for focal CHI in 30 children PATIENTS AND METHODS: All showed an ABCC8 or KCNJ... more Results of surgery for focal CHI in 30 children PATIENTS AND METHODS: All showed an ABCC8 or KCNJ11 mutation. After PET/CT in 29 children and PET/MRT in 1 case, frozen-section guided resection was performed, in left-sided cases by laparoscopy. Mean age at surgery was 11.7 months (2-49). In 28/30 children, the PET/CT or MRT correlated with histopathology. In two cases, a focal lesion was undectable; one of these was cured, one not. In total, 24 children showed lesions with sizes of 5-12 mm. All were cured instantly. In four children with huge lesions in the pancreatic head, pathological cells remained at the resection margins. One child was cured instantly, two children after a 2nd surgery, and one child was not cured, even after three surgeries. The overall cure rate was 93%. Imaging, surgical findings, histopathology and clinical outcome in surgery for focal CHI match in most, but not all cases.
We analysed allelic deletions on chromosome 5 in microdissected human non-small cell lung cancers... more We analysed allelic deletions on chromosome 5 in microdissected human non-small cell lung cancers. Thirty-four primary squamous cell carcinomas, 15 primary adenocarcinomas and five regional lymph node metastases were investigated for loss of heterozygosity (LOH) in chromosomal region 5p15-q21. The sites analysed included the APC tumor suppressor gene at 5q21, five polymorphic microsatellite markers and the putative tumor suppressor locus del-27, that was assigned to chromosomal region 5p13-12 by fluorescence in situ hybridization (FISH) analysis. Allelic deletions encompassed larger genomic regions more often in squamous cell carcinomas than in adenocarcinomas. The del-27 amd APC regions were identified as two distinct regions with the highest LOH frequencies within 5p15-q21. In squamous cell carcinomas LOH frequencies were 73% at the del-27 and 70% at the APC locus. In adenocarcinomas LOH at the del-27 and APC loci occurred in 38% of the informative cases. Allelic deletion of the A...
In 1996 Wittwer et al. described a new "mental retardation" syndrome with multiple congenital ano... more In 1996 Wittwer et al. described a new "mental retardation" syndrome with multiple congenital anomalies (thereupon named Wittwer syndrome OMIM 300421) in three male siblings of a family (Fig. 1A-D). One of the patients had died at the age of eight months (Fig. 1D). In addition to severe intellectual disability the anomalies included prenatal and severe postnatal growth retardation, dysmorphic features, blindness due to microphthalmia or optic atrophy, moderate to severe hearing loss, epilepsy, delayed bone maturation, and further congenital malformations. Progressive skeletal lesions with osteoplastic and osteoclastic changes were recognized upon clinical re-examination [Wieland et al., 2002]. The karyotype appeared normal. Pedigree analysis was highly suggestive of X-linkage since three of four male siblings born to two carrier sisters were affected. A linkage interval was assigned to Xp22.3 by haplotype analysis. Further investigation using microsatellite and EST markers refined the proposed disease locus between DXS8095 and DXS7108 comprising 3.9-6.1 Mb and showed no evidence for deletion indicative of a continuous gene deletion syndrome within this linkage interval [Wieland et al., 2002]. Recently, we had the opportunity to re-evaluate the two living affected males clinically as well as genetically. Array-based molecular karyotyping using an Affymetrix Cytoscan HD SNP-array revealed a cryptic genomic rearrangement in both patients involving deletion of about 8.4 Mb on 4p16.3p16.1 and duplication of about 3.9 Mb on 17q25.3 (arr[hg19] 4p16.3p16.1(68,345-8,496,780)x1,17q25.3 (77,174,428-81,041,938)x3, Fig. 1E). Fluorescence in situ hybridization (FISH) confirmed the array results and identified the derivative chromosome der(4)t(4;17) in the patients (Fig. 1F) and the balanced translocation in both female carriers. Deletions involving chromosome region 4p16.3 cause Wolf
Craniofrontonasal syndrome (CFNS; OMIM # 304110) is a rare X-linked disorder with greater severit... more Craniofrontonasal syndrome (CFNS; OMIM # 304110) is a rare X-linked disorder with greater severity in heterozygous females than in hemizygous males. CFNS is characterized by coronal craniosynostosis, frontal bossing, severe hypertelorism, craniofacial asymmetry, downslant palpebral fissure, broad nasal root, bifid nasal tip, grooved fingernails, curly wiry hair, and abnormalities of the thoracic skeleton. There are very few cases describing association of CFNS with heart defects. We discuss a very rare feature: atrial septal defect in a molecularly confirmed case of CFNS.
Oncology Research Featuring Preclinical and Clinical Cancer Therapeutics, 2001
We have determined the genomic structure of the candidate tumor suppressor gene DICE1 (DDX26). Th... more We have determined the genomic structure of the candidate tumor suppressor gene DICE1 (DDX26). The DICE1 gene colocalizes with microsatellite marker D13S284 telomeric to the RB1 gene in chromosomal region 13q14.3. The DICE1 gene encodes 18 exons that are preceded by a GC-rich promoter region. CpG sites flanking a predicted TATA box were found to be hypermethylated in tumor cells that exhibited decreased DICE1 expression. This suggests tumor-specific transcriptional silencing of the DICE1 gene may occur. Aberrantly spliced products were detected in two of three DICE1expressing cell lines. The predicted DICE1 amino acid sequence is evolutionarily conserved in mouse, fruit fly (D. melanogaster), and nematode (C. elegans). A DEAD box characteristic of ATP-dependent helicases is the predominant motif found in DICE1 and its mouse and fruit fly homologues. Motifs other than the DEAD box are reminiscent of members of the helicase superfamily II but there is considerable variation from the typical DEAD box helicases. Expression of DICE1 green fluorescent fusion protein showed a preferential localization of DICE1 in the nucleus. This suggests that DICE1 is involved in nuclear processes such as DNA repair, transcription, or RNA splicing.
Craniofrontonasal syndrome (CFNS) is characterized by body asymmetry, midline defects, skeletal a... more Craniofrontonasal syndrome (CFNS) is characterized by body asymmetry, midline defects, skeletal abnormalities, and dermatological abnormalities. It is a very peculiar X-linked syndrome because females are affected whereas male carriers show no or only mild abnormalities. Using a combination of positional approach and candidate gene strategy the EFNB1 gene in Xq12 was identified as the major causative gene of this condition. So far, 46 EFNB1 mutations have been detected in CFNS patients. The majority of the mutations lead to premature termination codons. Because the encoded protein ephrin-B1 is involved in migration of neural crest cells we propose that CFNS is a novel type of neurocrestopathy. The absent or mild phenotype in male carriers may be explained by the promiscuity of the ephrin ligand/receptor system. The more severe manifestation in females may be explained by cellular interference that is caused by the combination of ephrin ligand/receptor promiscuity and the consequences of random X inactivation in distinct cellular compartments.
We have previously observed loss of heterozygosity (LOH) at a single locus (del-27) on human chro... more We have previously observed loss of heterozygosity (LOH) at a single locus (del-27) on human chromosome 5p13-12 to correlate with bladder tumor progression. In this study, we examined 33 bladder tumors for their pattern of allelic loss on chromosome 5p using 7 microsatellite markers. In 14 of 15 bladder tumors with LOH at locus del-27, allelic loss was confined to chromosomal region 5p13-12. This region included the microsatellite marker D5S2025 that showed LOH in 5 of 11 (45%) informative cases with LOH at del-27. This suggests that D5S2025 and del-27 are located within a single critical region of LOH on 5p13-12 harboring a tumor suppressor gene involved in bladder tumor progression. Recurrent LOH at other loci was observed at microsatellite markers located at 5p15. However, these losses appeared to be independent of LOH at 5p13-12 and occurred predominantly in poorly differentiated (G3) and advanced (T3-T4) tumors.
BackgroundThe focal form of CHI is caused by an autosomal recessive pathogenic variant affecting ... more BackgroundThe focal form of CHI is caused by an autosomal recessive pathogenic variant affecting the paternal homologue of genes ABCC8 or KCNJ11 and a second somatic event specifically occurring in the affected islet of Langerhans. The approach of this study was to integrate the genetic changes occurring in pancreatic focal lesions of CHI at the genomic and transcriptional level.Research Design and MethodsPatients receiving therapeutic surgery and with proven ABCC8 or KCNJ11 pathogenic variants were selected and analyzed for loss of heterozygosity (LOH), changes in copy number and uniparental disomy (UPD) on the short am of chromosome 11 by molecular microarray analysis and methylation-specific MLPA. Gene expression was analyzed by RT-PCR and Massive Analysis of cDNA Ends (MACE).ResultsBoth genes, ABCC8 and KCNJ11, are located in proximity to the Beckwith-Wiedemann (BWS) imprinting control region on chromosome 11p15. Somatic paternal uniparental isodisomy (UPD) at chromosome 11p was...
Cutis marmorata telangiectatica congenita (CMTC) is characterized by coarse-meshed capillary malf... more Cutis marmorata telangiectatica congenita (CMTC) is characterized by coarse-meshed capillary malformations arranged in asymmetrically distributed patches. The disorder may be associated with hyper- or hypoplastic limbs, syndactyly, cleft palate, and glaucoma. Because the disease usually occurs sporadically, the concept of a lethal mutation surviving by mosaicism was proposed about 30 years ago. Here we describe three children with CMTC due to a postzygotic GNA11 mutation c547C > T (p.Arg183Cys), documented in saliva (patient 1) or lesional cutaneous tissue (patients 2 and 3). All three individuals had widespread and asymmetric CMTC which was present from birth and became fainter during the first years of life. Variably associated anomalies included glaucoma, choroidal capillary malformation, and body asymmetry. In previous case reports, postzygotic GNA11 mutations were documented in two cases of phacomatosis cesiomarmorata, being characterized by CMTC coexisting with segmental dermal melanocytosis. Moreover, postzygotic GNA11 mutations were noted in two CMTC patients described under the incorrect diagnosis of "nevus vascularis mixtus". Hence, the present cases convincingly support the concept that CMTC can be caused by mosaic GNA11 mutations and thus belongs to the GNA11-Related Capillary Nevus (GNARCAN) spectrum. In two other bona fide cases of CMTC, however, we were unable to find a mutation in GNA11, which may be explained either by our inability to detect a very low percentage of mutant cells or by genetic heterogeneity of the phenotype.
Background/Aim: The aim of this study was to present the long-term course of a patient with nevus... more Background/Aim: The aim of this study was to present the long-term course of a patient with nevus sebaceous syndrome (NSS). Recent genetic studies place the syndrome in the emerging group of so-called RASopathies. The focus of the report is on surgical treatment and morphological and genetic findings of the face and oral cavity. Case Report: A female patient was treated for congenital alterations of facial skin and oral mucosa. The oral lesions were removed repeatedly. Eruption of teeth on the lesion sites was made easier by the measures taken. However, after repeated ablation of the affected gingiva, the periodontal papillomatous epithelium redifferentiated into the same reddish, conspicuous, hyperplastic epithelium. The teeth in the affected region showed noticeable changes in position, surface, and shape. A HRAS mutation was detected only in the regions of altered oral epithelia and not in adjacent soft tissues. Conclusion: Reports on NSS rarely address oral manifestations. The recorded alterations of oral soft and hard tissues in NSS indicate a topographical relationship between the development of oral mucosa and teeth as well as the long-lasting impact of a sporadic mutation on organ development at this site. Epidermal nevi (EN) are mosaic cutaneous developmental disorders (1-6). EN are differentiated according to the predominant epithelial cell types (7). The terminology of nevi refers to the histological components of the lesion (8). If extracutaneous findings are noted in addition to EN in an individual, this constellation is referred to as epidermal nevus syndrome (ENS) (1-6, 9-12). Some authors have used the term 'ENS' to describe a distinct entity, in particular (linear) nevus sebaceous syndrome (NSS) (synonymous: Schimmelpenning-Feuerstein-Mims (SFM) syndrome, Naevus sebaceous Jadassohn (syndrome), Solomon syndrome, and further terms) (1-6, 8, 10). Other authors subsumed a group of cutaneous diseases characterized by nevi and extracutaneous findings under the term 'ENS' (1, 10). Currently, the term 'ENS' is mostly used as an umbrella designation for several syndromes describing diseases with a potentially large variety of physical findings that frequently first attract attention through noticeable alterations in superficial skin layers, in particular nevi (3-5, 8). With this broad sense, ENS also includes nevi that have adnexal differentiation (10). 274 This article is freely accessible online.
Neurofibromatosis type 1 (NF-1) predisposes to juvenile myelomonocytic leukemia (JMML) via loss o... more Neurofibromatosis type 1 (NF-1) predisposes to juvenile myelomonocytic leukemia (JMML) via loss of function of the NF1 tumor suppressor gene and consecutive deregulation of Ras signal transduction. Affected individuals usually carry one defective NF1 allele in the germline; somatic inactivation of the second NF1 allele in hematopoietic cells is associated with transformation to leukemia. We previously demonstrated that a major mechanism for biallelic loss of NF1 function in patients with JMML/NF-1 is mitotic recombination leading to uniparental disomy (UPD) of the 17q chromosome arm (Flotho, 2007; Steinemann, 2010). Using contemporary resequencing and microarray technology, we have now revisited the genetics of NF1 inactivation in JMML. Specifically, we addressed two questions: 1) Are genetic findings in leukemic cells of JMML/NF-1 patients consistent with the clinical diagnosis and the two-hit concept? 2) Does the quintuple-negative (QN) group of JMML (patients without clinical evi...
Background/Aim: Neurofibromatosis type 1 (NF) is an autosomal dominant hereditary disease. The ca... more Background/Aim: Neurofibromatosis type 1 (NF) is an autosomal dominant hereditary disease. The cardinal clinical findings include characteristic skeletal alterations. Difficulties in diagnosis and therapy can arise if an individual has further illnesses. Case Report: This is a case report of a 16-year-old patient affected by NF1. She also suffered from Alagille syndrome and the consequences of fetal alcohol exposure. The patient's facial phenotype showed findings that could be assigned to one or more of the known diseases. The patient was referred for treating a cherubismlike recurrent central giant cell granuloma (CGCG) of the jaw. The patient developed bilateral, multilocular nonossifying fibromas (NOF) of the long bones of the lower extremity. Treatment of the skeletal lesions consisted of local curettage. While NOF regressed after surgery, the CGCG of the jaw remained largely unchanged. Extensive genetic tests confirmed a previously unknown germline mutation in the JAG1 gene, the germline mutation of the NF1 gene, and the somatic mutation in the NF1 gene in the diffuse plexiform neurofibroma, but not in the CGCG. Conclusion: Assigning facial findings to a defined syndrome is ambiguous in many cases and especially difficult in patients who have multiple diseases that can affect the facial phenotype. Surgical therapy should be adapted to the individual findings. Neurofibromatosis type 1 (NF1) is an autosomal dominant inherited disorder (1). The disease has a high penetrance (about 100%). However, the phenotype is extremely variable (2). The NF1 gene is located on chromosome 17q11.2 (3, 4). NF1 is a tumor suppressor gene syndrome (5) and the most common monogenetic disease predisposing to cancer (1). NF1 is primarily characterized by multiple skin tumors. The tumors are of neurogenic origin termed neurofibroma. Somatic mutations of NF1 gene in neurofibroma arise in Schwann cells or precursors of Schwann cells. Since Schwann cells originate from the neural crest, NF1 is rated among the diseases that are characterized by mutations in neural crest cells (6). The frequent and numerous neoplasms of NF1 patients arise primarily from the connective soft tissues. Genetic studies show that many of the different neoplasms arising in NF1 patients meet the criteria of somatic allelic loss of NF1 gene according to Knudson's two-hit hypothesis of tumor development (7). However, the unusual variety of symptoms and findings in NF1 patients go far beyond the spectrum of neoplastic lesions (1). Most cases are diagnosed by clinical examination (Table I). Diagnosis and treatment of NF1 patients can be made more difficult if other diseases develop in the same individual and 1711 This article is freely accessible online.
Article type : Letter to the Editor Detection of a multi-lineage mosaic NRAS mutation c.181C>A (p... more Article type : Letter to the Editor Detection of a multi-lineage mosaic NRAS mutation c.181C>A (p.Gln61Lys) in an individual with a complex congenital nevus syndrome
Results of surgery for focal CHI in 30 children PATIENTS AND METHODS: All showed an ABCC8 or KCNJ... more Results of surgery for focal CHI in 30 children PATIENTS AND METHODS: All showed an ABCC8 or KCNJ11 mutation. After PET/CT in 29 children and PET/MRT in 1 case, frozen-section guided resection was performed, in left-sided cases by laparoscopy. Mean age at surgery was 11.7 months (2-49). In 28/30 children, the PET/CT or MRT correlated with histopathology. In two cases, a focal lesion was undectable; one of these was cured, one not. In total, 24 children showed lesions with sizes of 5-12 mm. All were cured instantly. In four children with huge lesions in the pancreatic head, pathological cells remained at the resection margins. One child was cured instantly, two children after a 2nd surgery, and one child was not cured, even after three surgeries. The overall cure rate was 93%. Imaging, surgical findings, histopathology and clinical outcome in surgery for focal CHI match in most, but not all cases.
We analysed allelic deletions on chromosome 5 in microdissected human non-small cell lung cancers... more We analysed allelic deletions on chromosome 5 in microdissected human non-small cell lung cancers. Thirty-four primary squamous cell carcinomas, 15 primary adenocarcinomas and five regional lymph node metastases were investigated for loss of heterozygosity (LOH) in chromosomal region 5p15-q21. The sites analysed included the APC tumor suppressor gene at 5q21, five polymorphic microsatellite markers and the putative tumor suppressor locus del-27, that was assigned to chromosomal region 5p13-12 by fluorescence in situ hybridization (FISH) analysis. Allelic deletions encompassed larger genomic regions more often in squamous cell carcinomas than in adenocarcinomas. The del-27 amd APC regions were identified as two distinct regions with the highest LOH frequencies within 5p15-q21. In squamous cell carcinomas LOH frequencies were 73% at the del-27 and 70% at the APC locus. In adenocarcinomas LOH at the del-27 and APC loci occurred in 38% of the informative cases. Allelic deletion of the A...
In 1996 Wittwer et al. described a new "mental retardation" syndrome with multiple congenital ano... more In 1996 Wittwer et al. described a new "mental retardation" syndrome with multiple congenital anomalies (thereupon named Wittwer syndrome OMIM 300421) in three male siblings of a family (Fig. 1A-D). One of the patients had died at the age of eight months (Fig. 1D). In addition to severe intellectual disability the anomalies included prenatal and severe postnatal growth retardation, dysmorphic features, blindness due to microphthalmia or optic atrophy, moderate to severe hearing loss, epilepsy, delayed bone maturation, and further congenital malformations. Progressive skeletal lesions with osteoplastic and osteoclastic changes were recognized upon clinical re-examination [Wieland et al., 2002]. The karyotype appeared normal. Pedigree analysis was highly suggestive of X-linkage since three of four male siblings born to two carrier sisters were affected. A linkage interval was assigned to Xp22.3 by haplotype analysis. Further investigation using microsatellite and EST markers refined the proposed disease locus between DXS8095 and DXS7108 comprising 3.9-6.1 Mb and showed no evidence for deletion indicative of a continuous gene deletion syndrome within this linkage interval [Wieland et al., 2002]. Recently, we had the opportunity to re-evaluate the two living affected males clinically as well as genetically. Array-based molecular karyotyping using an Affymetrix Cytoscan HD SNP-array revealed a cryptic genomic rearrangement in both patients involving deletion of about 8.4 Mb on 4p16.3p16.1 and duplication of about 3.9 Mb on 17q25.3 (arr[hg19] 4p16.3p16.1(68,345-8,496,780)x1,17q25.3 (77,174,428-81,041,938)x3, Fig. 1E). Fluorescence in situ hybridization (FISH) confirmed the array results and identified the derivative chromosome der(4)t(4;17) in the patients (Fig. 1F) and the balanced translocation in both female carriers. Deletions involving chromosome region 4p16.3 cause Wolf
Craniofrontonasal syndrome (CFNS; OMIM # 304110) is a rare X-linked disorder with greater severit... more Craniofrontonasal syndrome (CFNS; OMIM # 304110) is a rare X-linked disorder with greater severity in heterozygous females than in hemizygous males. CFNS is characterized by coronal craniosynostosis, frontal bossing, severe hypertelorism, craniofacial asymmetry, downslant palpebral fissure, broad nasal root, bifid nasal tip, grooved fingernails, curly wiry hair, and abnormalities of the thoracic skeleton. There are very few cases describing association of CFNS with heart defects. We discuss a very rare feature: atrial septal defect in a molecularly confirmed case of CFNS.
Oncology Research Featuring Preclinical and Clinical Cancer Therapeutics, 2001
We have determined the genomic structure of the candidate tumor suppressor gene DICE1 (DDX26). Th... more We have determined the genomic structure of the candidate tumor suppressor gene DICE1 (DDX26). The DICE1 gene colocalizes with microsatellite marker D13S284 telomeric to the RB1 gene in chromosomal region 13q14.3. The DICE1 gene encodes 18 exons that are preceded by a GC-rich promoter region. CpG sites flanking a predicted TATA box were found to be hypermethylated in tumor cells that exhibited decreased DICE1 expression. This suggests tumor-specific transcriptional silencing of the DICE1 gene may occur. Aberrantly spliced products were detected in two of three DICE1expressing cell lines. The predicted DICE1 amino acid sequence is evolutionarily conserved in mouse, fruit fly (D. melanogaster), and nematode (C. elegans). A DEAD box characteristic of ATP-dependent helicases is the predominant motif found in DICE1 and its mouse and fruit fly homologues. Motifs other than the DEAD box are reminiscent of members of the helicase superfamily II but there is considerable variation from the typical DEAD box helicases. Expression of DICE1 green fluorescent fusion protein showed a preferential localization of DICE1 in the nucleus. This suggests that DICE1 is involved in nuclear processes such as DNA repair, transcription, or RNA splicing.
Craniofrontonasal syndrome (CFNS) is characterized by body asymmetry, midline defects, skeletal a... more Craniofrontonasal syndrome (CFNS) is characterized by body asymmetry, midline defects, skeletal abnormalities, and dermatological abnormalities. It is a very peculiar X-linked syndrome because females are affected whereas male carriers show no or only mild abnormalities. Using a combination of positional approach and candidate gene strategy the EFNB1 gene in Xq12 was identified as the major causative gene of this condition. So far, 46 EFNB1 mutations have been detected in CFNS patients. The majority of the mutations lead to premature termination codons. Because the encoded protein ephrin-B1 is involved in migration of neural crest cells we propose that CFNS is a novel type of neurocrestopathy. The absent or mild phenotype in male carriers may be explained by the promiscuity of the ephrin ligand/receptor system. The more severe manifestation in females may be explained by cellular interference that is caused by the combination of ephrin ligand/receptor promiscuity and the consequences of random X inactivation in distinct cellular compartments.
We have previously observed loss of heterozygosity (LOH) at a single locus (del-27) on human chro... more We have previously observed loss of heterozygosity (LOH) at a single locus (del-27) on human chromosome 5p13-12 to correlate with bladder tumor progression. In this study, we examined 33 bladder tumors for their pattern of allelic loss on chromosome 5p using 7 microsatellite markers. In 14 of 15 bladder tumors with LOH at locus del-27, allelic loss was confined to chromosomal region 5p13-12. This region included the microsatellite marker D5S2025 that showed LOH in 5 of 11 (45%) informative cases with LOH at del-27. This suggests that D5S2025 and del-27 are located within a single critical region of LOH on 5p13-12 harboring a tumor suppressor gene involved in bladder tumor progression. Recurrent LOH at other loci was observed at microsatellite markers located at 5p15. However, these losses appeared to be independent of LOH at 5p13-12 and occurred predominantly in poorly differentiated (G3) and advanced (T3-T4) tumors.
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Papers by Ilse Wieland