Refinement of the deletion in 7q21.3 associated with split hand/foot malformation type 1 and Mondini dysplasia.
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Abnormalities, Multiple↗
Biomedical subjects
I Wieland
Publications and source records attributed to I Wieland.
Infrequent genetic alterations of the tumor suppressor gene PTEN/MMAC1 in squamous cell carcinoma of the oral cavity.
BACKGROUND: Fifty tumor specimens from primarily untreated patients were analyzed to elucidate the involvement of the tumor suppressor gene PTEN/MMAC1 in the development of oral squamous cell cancer. METHODS: Eight microsatellite markers, spanning 10 cM of genomic DNA located centromeric, telomeric or intragenic of PTEN/MMAC1 were used for loss of heterozygosity (LOH) and breakpoint analysis. The microsatellite panel within or in close proximity (1 cM) to the 10q23.3 locus showed a LOH rate of 12%. Complete sequence analysis of the genes coding region was performed in all 10 cases that exhibited LOH in one of the eight microsatellite markers within or around the PTEN/MMAC1 gene. Comparative multiplex PCR reactions served to screen for homozygous deletions. RESULTS: There was no association between allelic loss of the gene, overall patient survival and recurrence-free survival. Sequencing did not reveal any mutation in the coding region of PTEN/MMAC1. Differential PCR analysis failed to detect any homozygous deletion. CONCLUSIONS: We conclude that PTEN/MMAC1 gene alterations do not play a key role in tumorigenesis of oral squamous cell cancers.
Adult↗
Mapping of a further locus for X-linked craniofrontonasal syndrome.
Craniofrontonasal syndrome is a rare dysostosis syndrome with an unusual pattern of X-linked inheritance, because males are usually not or less severely affected than females. Previously, a CFNS locus has been localised in Xp22. We report on a haplotype analysis in a German CFNS family, mapping the CFNS locus to the pericentromeric region of the X chromosome. This discrepancy can be explained by locus heterogeneity. Furthermore, random X inactivation could be demonstrated in affected females. The most plausible interpretation for this unusual pattern of X-linked inheritance is metabolic interference. Consequently, we propose that the CFNS gene escapes X inactivation.
Cell Line↗
Molecular characterization of the DICE1 (DDX26) tumor suppressor gene in lung carcinoma cells.
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 DICE1 expressing 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.
Animals↗
Loss of heterozygosity analysis on chromosome 5p defines 5p13-12 as the critical region involved in tumor progression of bladder carcinomas.
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.
Alleles↗
Isolation of DICE1: a gene frequently affected by LOH and downregulated in lung carcinomas.
In the development and progression of sporadic tumors multiple tumor suppressor genes are inactivated that may be distinct from predisposing cancer genes. Previously, a tumor suppressor locus on human chromosome 13q14 that is distinct from the retinoblastoma predisposing gene 1 (RB1) has been identified in lung, head and neck, breast, ovarian and prostate tumors. By an approach that combines genomic difference cloning and positional cloning we isolated the cDNA of a novel gene (DICE1) located at 13q14.12-14.2. The DICE1 gene is highly conserved in evolution and its mRNA is expressed in a wide variety of fetal and adult tissues. The DICE1 cDNA encodes a predicted protein of 887 amino acids corresponding to an 100 kD protein that shows 92.9% identity to the carboxy-terminal half of the mouse EGF repeat transmembrane protein DBI-1. The DBI-1 protein interferes with the mitogenic response to insulin-like growth factor 1 (IGF-I) and is presumably involved in anchorage-dependent growth. When compared to normal lung tissue expression of the DICE1 mRNA was reduced or undetectable in the majority of non-small cell lung carcinomas analysed. The location of the DICE1 gene in the region of allelic loss, its high evolutionary conservation and the downregulation of expression in carcinoma cells suggests that DICE1 is a candidate tumor suppressor gene in non-small cell lung carcinomas and possibly in other sporadic carcinomas.
3T3 Cells↗
A novel member of the NF2/ERM/4.1 superfamily with growth suppressing properties in lung cancer.
A novel putative tumor suppressor gene and member of the NF2/ERM/ 4.1 superfamily was isolated using Differential Display PCR (DDPCR) on primary lung tumors. When reintroduced into nonexpressing non-small cell lung carcinoma cell lines, this gene, named DAL-1 (for Differentially expressed in Adenocarcinoma of the Lung), was shown to suppress growth. In addition, significantly reduced expression (>50%) of DAL-1 was measured in 39 primary non-small cell lung carcinoma tumors as compared with patient-matched normal lung tissue. Immunocytochemical staining with a polyclonal anti-DAL-1 antibody localized the protein to the plasma membrane, particularly at cell-cell contact points, a pattern reminiscent of other members of the protein 4.1 superfamily including ezrin and NF2. The data suggest DAL-1 is a novel membrane-associated protein with potential to play an important role in the origin and progression of lung cancer.
Amino Acid Sequence↗
Genetic alterations of the tumor suppressor gene PTEN/MMAC1 in human brain metastases.
The high mutation rate in advanced brain tumors, recent functional studies, and the high frequency of mutations in prostate metastases all strongly suggest that PTEN/MMAC1 alterations are involved in the formation of metastases. We searched for genetic alterations in the PTEN/MMAC1 gene in 56 consecutive brain metastases from various primary tumors by loss of heterozygosity (LOH), direct sequence analysis, and differential PCR analysis. The highest LOH rates were detected in metastases deriving from lung (67%) and breast (64%) cancers. Three (25%) of the eight detected inactivating mutations (one nonsense mutation, one splice-site mutation, one 11-bp deletion, and five homozygous deletions) were found in metastases originating from 12 different lung carcinomas, suggesting that PTEN/MMAC1 alterations may play a role in the progression of this tumor. With the exception of lung carcinomas, our findings indicate that genetic abnormalities of the PTENM/MMAC1 gene are only involved in a relatively small subset of brain metastases. However, the discrepancy between the high overall LOH rate (50%) and the low frequency of PTEN/MMAC1 mutation detection rate (14%) suggests the presence of one or more additional tumor suppressor genes on chromosome 10q.
Alleles↗
Deletion analysis at the DEL-27, APC and MTS1 loci in bladder cancer: LOH at the DEL-27 locus on 5p13-12 is a prognostic marker of tumor progression.
Inactivation of relevant tumor-suppressor genes by allelic or homozygous deletion is a characteristic event in tumor cells. Here, the prognostic value of allelic deletions on 5p13-12 at the putative del-27 tumor-suppressor locus and in the APC tumor-suppressor gene on 5q21, as well as homozygous deletions of the MTS1 (p16INK4, CDKN 2) tumor-suppressor gene on 9p21 was assessed in 87 bladder cancers using microdissection and PCR-based assays. Tumor-specific LOH was detected in 10 of 38 (26%, del-27), and 15 of 30 (50%, APC) informative specimens. Homozygous deletion of the MTS1 gene was detected in 33% of 84 tumors investigated. These deletion frequencies implicate the 3 tumor-suppressor regions in the genesis of transitional-cell carcinoma. In contrast to deletions of the APC or MTS1 genes, LOH at the del-27 locus correlated with tumor progression. This suggests that loss of the putative tumor-suppressor gene DEL-27 is involved in an aggressive behavior of the tumor cells and appears to be a prognostic marker for the clinical outcome of patients with transitional-cell carcinoma.
Carcinoma, Transitional Cell↗
Detection of loss of heterozygosity in the APC tumor suppressor gene in nonpapillary renal cell carcinoma by microdissection and polymerase chain reaction.
The role of the APC (adenomatous polyposis coli) tumor suppressor gene in the genesis of nonpapillary renal cell carcinoma is addressed. The frequency of allelic deletion in the APC gene was analyzed using microdissection of the tumor specimens and a PCR (polymerase chain reaction)-based assay for the detection of intragenic loss of heterozygosity (LOH). Twelve of 29 carcinomas investigated were informative (41%). In five of these (42%) LOH was detected in the APC gene, LOH did not correlate with tumor grade or stage. This high frequency of intragenic LOH suggests an implication of the APC gene or a closely linked gene in the genesis of a subset of nonpapillary renal cell carcinoma. The use of a microdissection technique allows the reliable detection of tumor-specific LOH when using a PCR-based assay.
Aged↗
Microbeam MOMeNT: non-contact laser microdissection of membrane-mounted native tissue.
The analysis of tissue-specific genetic alterations depends on the selective procurement of homogeneous cell populations. Microbeam microdissection of membrane-mounted native tissue (MOMeNT) permits the rapid, selective, and low-contamination procurement of tumor or other cells from histological sections by non-thermic non-contact laser microdissection. Tissue sections are mounted on a specifically designed ultrathin transparent supporter membrane. Tissue together with the membrane are then dissected with an ultraviolet (337-nm) pulsed laser microbeam coupled into a robot-stage microscope. The ultraviolet laser causes dissection by cold photolysis due to the high photon density of the microbeam rather than by local heating. The track of the laser microbeam can be preselected freely on a video screen, and the size and form of the dissectates can thus be adapted to the histological features of the section with a delineation accuracy in the micron range. Polymerase chain reaction amplification of DNA from the dissectates is not impaired, and tumor-specific loss of heterozygosity of the APC gene as well as homozygous deletion of the MTS1 gene are demonstrated in bladder carcinomas. Taken together, microbeam MOMeNT is a novel technique that utilizes membrane-based microdissection by an ultraviolet laser microbeam, thus providing a flexible, easy-to-use high-performance tool for the molecular pathologist.
Carcinoma, Transitional Cell↗
Allelic deletion mapping on chromosome 5 in human carcinomas.
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 APC gene and at the del-27 locus was also detected in the metastases. The results suggest involvement of at least two tumor suppressor genes on chromosome 5 in lung tumorigenesis.
Base Sequence↗
Microsatellite instability and loss of heterozygosity at the hMLH1 locus on chromosome 3p21 occur in a subset of nonsmall cell lung carcinomas.
Microsatellite alterations observed in tumor specimens may reflect genomic instability due to defective mismatch repair genes. To investigate whether this occurs in human nonsmall cell lung carcinomas we have analyzed microsatellite instability at 5 marker loci and loss of heterozygosity (LOH) at the hMLH1 locus on chromosome 3p21 using the polymerase chain reaction. Of a total of 49 nonsmall cell lung carcinomas examined, 43% (13 of 30 informative cases) showed LOH at 3p21 and 29% (14 of 49) exhibited microsatellite instability at one or multiple loci. LOH of the mismatch repair gene hMLH1 at 3p21 occurred in 82% (9 of 11 informative cases) of the tumors with microsatellite instability. This suggests that defects in the mismatch repair gene hMLH1 at 3p21 may be involved in microsatellite instability and tumorigenesis of a subset of nonsmall cell lung carcinomas. However, in those nonsmall cell lung carcinomas without microsatellite instability LOH at 3p21 probably involved another tumor suppressor gene(s) in this chromosomal region.
Carcinoma, Non-Small-Cell Lung↗
Frequent allelic deletion at a novel locus on chromosome 5 in human lung cancer.
Frequent allelic deletions in tumor cells are indicative of the inactivation of tumor suppressor genes. Recently, we isolated the single-copy sequence del-27 (I. Wieland, M. Böhm, and S. Bogatz, Proc. Natl. Acad. Sci. USA, 89: 9705-9709, 1992). Here we show that del-27 detects a restriction fragment length polymorphism that allows examination for loss of heterozygosity (LOH) in tumor specimens. LOH at the del-27 locus occurred in 57% (4 of 7) of the informative lung carcinomas independent of the histopathological differentiation grade. LOH for exon 11 of the APC gene occurred in 71% (5 of 7) of the informative cases but was not associated with LOH at the del-27 locus. The del-27 sequence was localized to chromosome 5p13-5q14, proximal to the MCC/APC region, using a somatic cell hybrid panel. Together with our previous finding that del-27 is deleted homozygously in a lung carcinoma cell line, these results suggest that del-27 is linked closely to a novel putative tumor suppressor gene.
Alleles↗
Differences of E-cadherin expression levels and patterns in human lung cancer.
Fifty-two lung carcinomas obtained at surgical resection were examined by immunofluorescence for their expression levels and patterns of the calcium-dependent intercellular adhesion molecule E-cadherin. In well-differentiated squamous cell and adenocarcinomas expression of E-cadherin was confined to the lateral cell border, similar to the expression level and pattern of normal lung tissue. The E-cadherin level was reduced and the expression pattern was spotty or diffuse in moderately and poorly differentiated squamous cell carcinomas and in small cell carcinomas of the lung. Also, most metastases resected had a reduced level and an altered pattern of E-cadherin expression. In contrast, no such correlation was found in adenocarcinomas of the lung. This indicates that different cellular mechanisms are responsible in the progression of squamous cell carcinomas versus adenocarcinomas of the lung.
Adenocarcinoma↗
Differences of E-cadherin expression levels and patterns in primary and metastatic human lung cancer.
Normal lung epithelium and 52 lung carcinomas obtained at surgical resection were examined by immunofluorescence for their expression levels and patterns of the calcium-dependent intercellular adhesion molecule E-cadherin. In dysplastic lung tissue and in well-differentiated squamous cell and adenocarcinomas, expression of E-cadherin was confined to the lateral cell border, similar to the expression level and pattern of normal lung tissue. The E-cadherin level was reduced and expression pattern was spotty or diffuse in moderately and poorly differentiated squamous cell and in small cell carcinomas of the lung. Most metastases resected also had a reduced level and an altered pattern of E-cadherin expression. In contrast, no such correlation was found in adenocarcinomas of the lung. This indicates that different cellular mechanisms are responsible in the progression of squamous cell carcinomas and adenocarcinomas of the lung.
Adenocarcinoma↗
Isolation of region specific single-copy probes from human chromosome 1q23-->1q25.
Single-copy sequences of chromosome bands 1q23-->1q25 were enriched by subtractive hybridization of digoxigenin oligonucleotide-labeled DNA from a somatic cell hybrid containing human chromosome 1 with DNA from a somatic cell hybrid containing a deleted human chromosome 1, del(1)(q23q25). These sequences were purified with an immobilized anti-digoxigenin antibody, amplified by polymerase chain reaction (PCR) and cloned. The majority of clones contained single-copy sequences, thus allowing direct screening of human genomic DNA. With pools of probes complex hybridization patterns as well as differences in hybridization patterns between genomes were observed in Southern blotting experiments. Nine clones containing independent single-copy sequences from chromosome bands 1q23-->1q25 were isolated and sequenced to generate sequence-tagged sites (STSs). Using PCR, region specific genomic clones containing large inserts were identified in human genomic lambda phage and cosmid libraries. Thus, region specific genomic probes generated by genomic difference cloning are useful for identifying deletions and rearrangements, for generating STSs and for isolating genomic clones containing large inserts of a particular chromosomal region.
Base Sequence↗
Detection of tumor-specific homozygous deletions in human biopsies by polymerase chain reaction.
Cancer is associated with homozygous deletions of specific DNA sequences that are in some instances too small to be detectable by cytogenetic methods or Southern blot analysis. Such small tumor-specific deletions can be detected, however, by the polymerase chain reaction (PCR) provided that tumor cells are meticulously and verifiably isolated from contaminating nontumor cells. Nontumor cells can give positive PCR results and thus obscure the detection of deletions. Using a method that allows accurate and verifiable excision of tumor cells for subsequent PCR analysis, homozygous deletions, one in a putative tumor suppressor gene on chromosome 8 and one in the p53 gene, were detected in two out of 20 human lung carcinomas investigated.
Adenocarcinoma↗