Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P06889 (Mol)
630,302 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Nasal polyposis is a chronic inflammatory condition of the upper airways characterized by infiltration of activated inflammatory cells, particularly eosinophils. Granulocyte/macrophage colony-stimulating factor (GM-CSF) is a cytokine with powerful biologic effects including the regulation of survival, proliferation, and activation of granulocytes as well as differentiation of hemopoietic cells. To examine the potential role of GM-CSF in the pathogenesis of this condition, we investigated gene expression and production of GM-CSF in nasal polyp tissues as well as in the normal nasal mucosa. Immunoreactive GM-CSF was detected by enzyme-linked immunosorbent assay in the 24-h supernatant of nasal polyp tissues placed in culture. By Northern blot analysis and Southern blot analysis following a reverse-transcription polymerase chain reaction using a human GM-CSF cDNA probe, we detected GM-CSF mRNA in nasal polyp tissues, as well as in the tissue from a patient with allergic rhinitis, but not in the normal nasal mucosa. By in situ hybridization using the same probe, cells expressing mRNA specific for GM-CSF were observed in nasal polyp tissues and in the allergic nasal mucosa. In addition, by the combination of in situ hybridization and counterstaining with chromotrope 2R, we demonstrated that approximately 30% of eosinophils infiltrating the polyp tissue express the GM-CSF gene. These results suggest a novel mechanism by which eosinophils may contribute to the pathogenesis of chronic inflammatory diseases such as nasal polyposis, allergic rhinitis, and, by implication, asthma.
Am J Respir Cell Mol Biol 1991 Dec
PMID:Granulocyte/macrophage colony-stimulating factor (GM-CSF) gene expression by eosinophils in nasal polyposis. 195 76

The expansion and contraction of CTG and CGG trinucleotide repeat sequences have been associated with several heritable genetic diseases. We developed a system for investigating the expansion of triplet repeat sequences in Escherichia coli in order to elucidate molecular mechanisms. Analysis of expanded regions using the interrupting CTA triplet sequence as a location marker within the CTG tract revealed that the expansion of large CTG repeats is one event rather than an accumulation of multiple small expansions and that the expansions occur more frequently in the region distal from the replication origin. Also, we showed that a loss of interruptions increases the expansion frequency. Thus, the instability of large triplet repeats in hereditary diseases occurs by a mechanism different from the instability in microsatellite sequences caused by defects in mismatch repair systems for certain sporadic cancers and hereditary non-polyposis colorectal cancers.
J Mol Biol 1996 May 17
PMID:CTG triplet repeats from the myotonic dystrophy gene are expanded in Escherichia coli distal to the replication origin as a single large event. 863 89

The DNA mismatch repair genes MSH2 and MLH1 have been shown to account for a major share of hereditary non-polyposis colorectal cancer (HNPCC). We searched for germline mutations in these genes in 35 HNPCC kindreds fulfilling the Amsterdam diagnostic criteria and in a further 20 kindreds with an average of four affected members per family but not meeting the formal criteria. We first screened for truncations by reverse transcriptase (RT)-PCR. If no mutation was found, we screened genomic DNA by a novel application of two-dimensional (2-D) DNA electrophoresis that allows the simultaneous study of all exons of each gene. All abnormalities were followed up by sequencing. Eight different pathogenic germline mutations were found, two in MSH2 and six in MLH1. We report three major conclusions. First, these mutations together accounted for 86% (30/35) of the kindreds meeting the Amsterdam criteria, but only 30% (6/20) of the remaining kindreds, suggesting differences in etiology. Second, MLH1 was involved in > 90% (34/36) of kindreds with a known predisposing mutation, suggesting that mutations in the MLH1 gene are responsible for most HNPCC kindreds in Finland. Third, our results indicate that the successive application of RT-PCR and 2-D DNA electrophoresis is a sensitive and efficient method for mutation screening in typical HNPCC.
Hum Mol Genet 1996 Jun
PMID:DNA mismatch repair gene mutations in 55 kindreds with verified or putative hereditary non-polyposis colorectal cancer. 877 90

We studied potential mechanisms of eosinophil accumulation in nonallergic chronic hyperplastic sinusitis with nasal polyposis (CHS/NP). We measured expression of endothelial vascular cell adhesion molecule-1 (VCAM-1), which mediates selective eosinophil transendothelial migration, the cytokines interleukin (IL)-1 beta, TNF-alpha and IL-13 which upregulate VCAM-1 expression, and the chemokine RANTES which mediates lymphocyte, monocyte, and eosinophil chemotaxis in chronic hyperplastic sinusitis with nasal polyposis (CHS/NP) nasal polyps (nonallergic versus allergic) and middle turbinate biopsies from normal controls. By immunohistochemical staining, the density of EG2+ eosinophils was increased in both the nonallergic and allergic CHS/NP subgroups compared to normal controls. VCAM-1 expression was significantly increased in CHS/NP subjects compared to normal controls (P = 0.0005), with the highest intensity seen in nonallergic CHS/NP. By in situ hybridization, the densities of IL-1 beta, TNF-alpha, IL-13, and RANTES mRNA+ cells were all increased in nonallergic CHS/NP compared to normal controls (P = 0.009, 0.0005, 0.0005, and 0.001, respectively). In comparison to allergic CHS/NP, nonallergic CHS/NP had a significantly higher tissue density of TNF-alpha (P = 0.04) and a lower density of IL-13 (P = 0.005) mRNA+ cells. In general, VCAM-1 expression correlated strongly in CHS/NP with the density of TNF-alpha (R = .91, P = 0.0005) but not the density of IL-1 beta, IL-13, or RANTES mRNA+ cells. We conclude that upregulation of VCAM-1 and elaboration of RANTES may contribute to the marked accumulation of eosinophils in nonallergic CHS/NP. TNF-alpha may play a critical role in VCAM-1 upregulation in this nonallergic eosinophilic disorder.
Am J Respir Cell Mol Biol 1996 Oct
PMID:Eosinophil infiltration in nonallergic chronic hyperplastic sinusitis with nasal polyposis (CHS/NP) is associated with endothelial VCAM-1 upregulation and expression of TNF-alpha. 887 77

This study compared colonoscopic findings in families meeting the Amsterdam criteria (A) for hereditary non-polyposis colorectal cancer (HNPCC) but stratified according to whether the familial cancers showed DNA microsatellite instability. DNA was extracted from paired samples of normal and cancer, and microsatellite instability was analysed at up to six loci. Families were termed replication error positive (RER+) when at least 50% of tumours tested per family were positive. Of 26 families studied 17 were RER+ and 9 were RER-. Cancers in the A/RER- families showed no right-sided predilection (P < 0.001). Colonoscopies have been performed on 182 at-risk members of A/RER+ families and 60 members of A/RER- families. More of the at-risk members of A/RER-families were found to have adenomas at colonoscopy (P = 0.095), but these were smaller than those of A/RER+ families (P = 0.19). The adenoma:carcinoma ratio was twice as high in A/RER- families (13:1) as in A/RER+ families (7:1). One of the A/RER- families had hyperplastic polyposis. The others do not appear to have attenuated familial adenomatous polyposis and are similar to the adenoma families or late-onset colorectal cancer families described by others. This study illustrates the importance of molecular technology in separating HNPCC from syndromes with overlapping phenotypes.
J Mol Med (Berl) 1996 Sep
PMID:Colorectal neoplasms detected colonoscopically in at-risk members of colorectal cancer families stratified by the demonstration of DNA microsatellite instability. 889 60

Desmoid tumours are generally very rare but occur about 100 times more frequently in the colorectal cancer predisposition syndrome familial adenomatous polyposis (MIM 175100), being represented in about 10% of patients. In addition to desmoid disease occurring in familial adenomatous polyposis (FAP) there exist familial infiltrative fibromatosis (MIM 135290) kindreds where there is no evidence of FAP. Previously we have described a kindred with familial infiltrative fibromatosis (FIF) in which desmoid tumours were associated with nonpolyposis colorectal cancer. FAP is caused by mutations in the APC gene and various genotype-phenotype relationships have been defined including reports that colorectal polyposis is less severe with mutations 5' to codon 157 and that the risk of desmoid tumours is high in FAP patients with APC gene mutations between codons 1444 and 1598. There is relatively little information on the phenotype of APC gene mutations 3' to codon 1598; however, one large family has been reported with a mutation at codon 1987 which presents with a highly variable phenotype which includes desmoid disease. We screened our original FIF kindred and three further families with a similar phenotype for mutations in the APC gene. A 4 bp frameshift deletion in codon 1962 was identified in the original FIF kindred and two further apparently unrelated families. Haplotype analysis suggests a common origin for the APC mutation in all three families. Affected individuals had no evidence of congenital hypertrophy of the retinal pigment epithelium. Colorectal polyposis was variable, and most affected patients had either none or a few late onset polyps. These findings demonstrate (i) that FAP and FIF are allelic, and (ii) that APC gene mutations which truncate the APC protein distal to the beta-catenin binding domain are associated with desmoid tumours, absent CHRPE and variable but attenuated polyposis expression.
Hum Mol Genet 1996 Dec
PMID:Familial infiltrative fibromatosis (desmoid tumours) (MIM135290) caused by a recurrent 3' APC gene mutation. 896 44

A genome-wide instability has been found in almost all analyzed malignant tumors from patients with hereditary non-polyposis colorectal cancer (HNPCC), and in a subgroup of sporadic (non-inherited) cancers of the same type. This mutator phenotype was initially seen as novel alleles at microsatellite loci (a family of repetitive DNA sequences) and was shown to be caused by mutations in the highly conserved mismatch repair genes. Mutations have been found in each of four of these human genes: hMSH2, hMLH1, hPMS1 and hPMS2, in the germline of HNPCC patients and in their tumors, as well as in sporadic tumors. These recent discoveries provide new molecular diagnostic tools for the detection of patients at high risk of developing carcinomas of the large bowel and other HNPCC-related tumors. Ongoing international research is progressively solving many of the unanswered questions at the genotypic and phenotypic levels of this newly identified mechanism in carcinogenesis.
Mol Med Today 1997 Feb
PMID:Microsatellite instability in human solid tumors. 906 3

Juvenile polyps are present in a number of Mendelian disorders, sometimes in association only with gastrointestinal cancer [juvenile polyposis syndrome (JPS)] and sometimes as part of known syndromes (Cowden, Gorlin and Banayan-Zonana) in association with developmental abnormalities, dysmorphic features or extra-intestinal tumours. Recently, a gene for JPS was mapped to 18q21.1 and the candidate gene DPC4 (SMAD4) was shown to carry frameshift mutations in some JPS families. We have analysed eight JPS families for linkage to DPC4. Overall, there was no evidence for linkage to DPC4; linkage could be excluded in two of the eight pedigrees and was unlikely in two others. We then tested these eight families and a further 13 familial and sporadic JPS cases for germline mutations in DPC4. Just one germline DPC4 mutation was found (in a familial JPS patient from a pedigree unsuitable for linkage analysis). Like all three previously reported germline mutations, this variant occurred towards the C-terminus of the DPC4 protein. However, our patient's mutation is a missense change (R361C); somatic missense mutations in DPC4 have been reported previously in tumours. We therefore confirm DPC4 as a cause of JPS, but show that there is considerable remaining, uncharacterized genetic heterogeneity in this disease.
Hum Mol Genet 1998 Nov
PMID:Mutations in DPC4 (SMAD4) cause juvenile polyposis syndrome, but only account for a minority of cases. 981 34

Mismatch repair genes are involved in increasing the fidelity of replication by specific repair of DNA polymerase incorporation errors. In Escherichia coli, the best studied mismatch repair (MMR) pathway is the methyl-directed long patch repair system which is mediated by three gene products; MutS, MutL and MutH. These are conserved in higher eukaryotes. Mutations in human homologues of these proteins have been shown to be implicated in hereditary non-polyposis colorectal cancer (HNPCC). Alterations in the coding regions of MMR genes result in a mutator phenotype with marked instability of microsatellite sequences, indicative of a deficiency in DNA repair.
Int J Mol Med 1998 Feb
PMID:DNA mismatch repair genes and their association with colorectal cancer (Review). 985 52

Defective DNA mismatch repair in human tumors leads to genome-wide instability of microsatellite repeats and a molecular phenotype referred to as microsatellite instability (MSI). MSI has been reported in a variety of cancers and is a consistent feature of tumors from patients with hereditary non-polyposis colorectal cancer. Approximately 20% of cancers of the uterine endometrium, the fifth most common cancer of women world-wide, exhibit MSI. Although the frequency of MSI is higher in endometrial cancers than in any other common malignancy, the genetic basis of MSI in these tumors has remained elusive. We investigated the role that methylation of the MLH1 DNA mismatch repair gene plays in the genesis of MSI in a large series of sporadic endometrial cancers. The MLH1 promoter was methylated in 41 of 53 (77%) MSI-positive cancers investigated. In MSI-negative tumors on the other hand, there was evidence for limited methylation in only one of 11 tumors studied. Immunohistochemical investigation of a subset of the tumors revealed that methylation of the MLH1 promoter in MSI-positive tumors was associated with loss of MLH1 expression. Immunohistochemistry proved that two MSI-positive tumors lacking MLH1 methylation failed to express the MSH2 mismatch repair gene. Both of these cancers came from women who had family and medical histories suggestive of inherited cancer susceptibility. These observations suggest that epigenetic changes in the MLH1 locus account for MSI in most cases of sporadic endometrial cancers and provide additional evidence that the MSH2 gene may contribute substantially to inherited forms of endometrial cancer.
Hum Mol Genet 1999 Apr
PMID:MLH1 promoter methylation and gene silencing is the primary cause of microsatellite instability in sporadic endometrial cancers. 1007 35


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