Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01034 (cystatin C)
 3,397 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Twenty-nine patients with acute myelocytic leukemia (AML) and 14 patients with Philadelphia chromosome-positive chronic myelocytic leukemia (CML) were analyzed to detect the presence of mutations in their ras genes by the polymerase chain reaction and oligonucleotide hybridization methods. Deoxyribonucleic acid (DNA) isolated from blood or bone marrow samples was screened for mutations in codons 12, 13 and 61 of N-ras and in codons 12 and 61 of K-ras and H-ras. We detected mutations of the ras gene in 7 patients with AML (7/29), all in N-ras. The mutations were 3 GGT- greater than GAT transitions in codon 12, 1 GGT- greater than TGT transition in codon 13, and 3 CAA- greater than AAA transitions in codon 61. No correlation has been observed between French-American-British subtypes and the incidence of N-ras mutation, nor between cytogenetic changes and the incidence of N-ras mutation. All ras gene mutations detected by the oligonucleotide hybridization method were further confirmed by direct sequencing. No mutations were detected in ras genes in samples from the 14 Philadelphia chromosome-positive CML patients (12 in chronic phase, 2 in blastic phase). These findings are in line with previous results indicating that ras gene mutations in the codons tested play only a small role in the tumorigenesis of CML.
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PMID:Mutation analysis of the ras gene in myelocytic leukemia by polymerase chain reaction and oligonucleotide probes. 168 80

The presence of activated transforming genes was investigated in four patients with therapy-related leukemia and in three with therapy-related myelodysplastic syndrome. DNA of bone marrow cells from six of the patients exhibited transforming activity in the tumorigenicity assay. Five of the six patients who were positive in the tumorigenicity assay contained activated N-ras oncogenes, and three contained activated K-ras oncogenes. Thus, concurrent activation of N-ras and K-ras oncogenes was observed in two patients. In vitro DNA amplification followed by oligonucleotide dot-blot analysis was used to investigate mutations in codons 12, 13, and 61 of the N-ras and K-ras oncogenes. Two patients exhibited an N-ras mutation, substituting aspartic acid (GAT) for glycine (GGT), and three patients exhibited an N-ras codon 13 mutation, substituting valine (GTT) for glycine. Two patients exhibited K-ras codon 12 mutations, substituting aspartic acid (GAT) or cysteine (TGT) for glycine (GGT), respectively, and one case exhibited a K-ras codon 61 mutation, substituting lysine (AAA) for glutamic acid (CAA). Cytogenetic analysis revealed that loss of chromosome 7 was frequent (four patients: 57%). Our data indicate that activation of N-ras and K-ras genes, as well as loss of heterozygosity for specific alleles on chromosome 7, plays a more important role in the leukemogenesis of both therapy-related leukemia and myelodysplastic syndrome.
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PMID:Transforming genes and chromosome aberrations in therapy-related leukemia and myelodysplastic syndrome. 185 83

Determination of the primary structure of abnormal Hbs on the basis of DNA sequencing of the globin gene obtained from a carrier of abnormal Hb was performed. DNA obtained from the leukocytes of the peripheral blood was amplified by the polymerase chain reaction (PCR) using the proper amplification primer set. Amplified DNA was digested with two different restriction endonucleases and cloned to vector M 13 mp 18 or mp 19, which had been digested with the same enzymes. DNA sequencing was done by the dideoxy chain termination method using T 7 DNA polymerase, and the abnormal Hbs whose primary structure was determined were as follows: Hb Fukuoka [beta 2 His(CAC/T)----Tyr(TAT)], Hb Machida [beta 6 Glu(GAG)----Gln (CAG)], Hb Hope [beta 136 Gly(GGT)----Asp(GAT)], Hb Hiroshima [beta 146 His(CAC)----Asp(GAC)] and Hb Kodaira [beta 146 His(CAC)----Gln(CAA)]. This method for determining the primary structure of abnormal Hbs might be more effective than the ordinary method, which involves amino acid analysis and amino acid sequencing of the abnormal peptide obtained from abnormal Hb.
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PMID:[Structural analysis of abnormal hemoglobin by the polymerase chain reaction (PCR) of genomic DNA]. 223 67

We examined the incidence of point mutation in codons 12, 13 and 61 of c-Ki-ras and N-ras genes in human hepatocellular carcinoma (HCC) using the polymerase chain reaction and oligonucleotide hybridization techniques. Among 34 tissues specimens surgically resected from 30 patients and 5 cell lines of human HCC, only two had ras point mutations; in one case, codon 12 of c-Ki-ras was altered from GGT, coding glycine, to GTT, coding valine; in the other case, codon 61 of N-ras was altered from CAA, coding glutamine, to AAA, coding lysine. Thus, point-mutational activation of ras oncogenes is an uncommon event in human HCC.
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PMID:Low incidence of point mutation of c-Ki-ras and N-ras oncogenes in human hepatocellular carcinoma. 254 5

Lung and liver tumors were induced in female A/J mice after treatment for 7 weeks (3 times/week, i.p.) with either 4-(N-methyl-N-nitrosamino)-1-(3-pyridyl)-1-butanone (NNK) (50 mg/kg) or nitrosodimethylamine (NDMA) (3 mg/kg). Both compounds can be activated via alpha-hydroxylation to methylating agents, while NNK may also undergo hydroxylation at the N-methyl carbon to form a pyridyloxobutylated adduct. The purpose of these studies was to identify and characterize the activated oncogenes present in tumors induced by NDMA and NNK. Following transfection of high molecular weight DNA onto NIH/3T3 mouse fibroblasts, transforming genes were detected in 90% of both NNK- (10 of 11) and NDMA- (9 of 10) induced lung tumors. In contrast, transformation of NIH/3T3 fibroblasts was observed only in 40% (2 of 5) and 13% (1 of 8) of the liver tumors from NNK- and NDMA-treated mice, respectively. Southern blot analysis indicated that the transforming gene present in all lung tumors was an activated K-ras oncogene. Both rearranged bands and amplified signals were detected in the transfectants. The one transformant from the NDMA-induced liver tumor contained an activated K-ras gene. In contrast, the two liver transformants from NNK-induced tumors did not contain an activated ras or raf gene. Hybridization with oligonucleotide probes that were centered around either codon 12 or 61 of the K-ras gene were utilized to localize the mutations. Activation of this gene appeared to occur largely via a mutation in codon 12 (15 of 20 transformants) and was observed with a similar frequency in pulmonary tumors induced by either compound. The remaining mutations were found in codon 61. The specific mutation within these two codons was determined by amplifying the exon containing the base change, followed by direct sequencing. With one exception the mutation observed in codon 12 was a GC to AT transition (GGT to GAT). One transformant contained a GC to TA transversion. The activating mutation detected in codon 61 was always an AT to GC transition of the middle A (CAA to CGA). The GC to AT mutation observed in codon 12 is consistent with the formation of the O6-methylguanine adduct. Similar concentrations (23 to 32 pmol/mumol deoxyguanosine) of this promutagenic adduct were detected in lungs during treatment with either NNK or NDMA.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Relationship between the formation of promutagenic adducts and the activation of the K-ras protooncogene in lung tumors from A/J mice treated with nitrosamines. 267 Feb 1

DNA isolated from blood or bone-marrow samples from 18 patients with acute non-lymphocytic leukemia (ANLL) and 14 patients with acute lymphocytic leukemia (ALL) was analyzed for the presence of mutations in the N-ras gene. Using synthetic oligonucleotide probes we detected mutations in 5 cases of ANLL; 4 GGT----GAT transitions in codon 12 and one CAA----AAA transversion in codon 61. One case exhibited homozygosity for the mutation. No mutations could be detected at these codons in the DNA of the 14 ALL patients. In a follow-up study with 3 of the above 5 patients, the mutation could no longer be detected in 2 cases following successful induction of clinical remission by chemotherapy. However, the mutated N-ras persisted in one patient who did not achieve remission. We show that oligonucleotide hybridization is a sensitive assay for the detection of N-ras point mutations, which in ANLL could be used to follow the fate of the leukemic clone during (and after) therapy.
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PMID:Mutation analysis of the N-ras proto-oncogene in active and remission phase of human acute leukemias. 327 90

Three series of biopsy specimens of premalignant and malignant oral lesions, together with seven human keratinocyte cultures, previously established from oral squamous cell carcinomas, were analysed for point mutation in exons 1 and 2 of the c-Ha-ras, c-Ki-ras and N-ras genes by direct nucleotide sequencing of DNAs amplified in the polymerase chain reaction (PCR). Only one out of 12 biopsy samples (8.3%), a well-differentiated carcinoma which was the latest in a series of floor of mouth lesions from 1 of the 3 patients studied, harboured a mutant c-Ha-ras gene, being heterozygous at codon 12 for a GGA-GTA change. One cell line (H357) showed heterozygosity in both exons 1 and 2 of c-Ha-ras, harbouring a GGT to AGT mutation over codon 13 and a CAG to CAA mutation over codon 61. The remaining six oral carcinoma cell lines (85.7%) were homozygous normal at both exons 1 and 2 of c-Ha-ras. All cell lines showed normal c-Ki-ras and N-ras loci. We conclude that ras gene mutation is an infrequent occurrence in the malignant progression of oral epithelial cells, despite the probable importance of chemical carcinogens in the aetiology of the disease. We emphasise the need to search for other cellular sequences which may be targets for chemical or viral carcinogens.
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PMID:Ras gene point mutation is a rare event in premalignant tissues and malignant cells and tissues from oral mucosal lesions. 818 May 79

In an effort to define the pathogenic relationship between ovarian neoplasms spanning the clinicopathological spectrum from benign to malignant, the incidence of Ki-ras and p53 mutations was determined in 20 ovarian cystadenomas, 20 low malignant potential (LMP) tumors of the ovary, and 23 ovarian carcinomas. Using DNA extracted from paraffin embedded tissue, polymerase chain reaction amplification, designed restriction fragment length polymorphism analysis, and DNA sequencing, 1 cystadenoma (5%), 6 LMP tumors (30%), and 1 ovarian carcinoma (4%) demonstrated an activated Ki-ras gene. All of the Ki-ras mutations identified except one were GGT to GAT transversions at codon 12. One LMP tumor demonstrated a CAA to CAC transversion at codon 61. Using polymerase chain reaction/single strand conformational polymorphism, DNA sequencing, and immunohistochemistry, 11 ovarian carcinomas (48%) demonstrated a p53 mutation. These mutations included 5 missense, 2 nonsense, and 1 frameshift mutation located within exons 6-8 and 3 mutations that were identified only by immunohistochemical staining. No p53 mutations could be identified in cystadenomas or LMP tumors. Clinically, the presence of either a Ki-ras or p53 mutation was associated with advanced stage disease. The pattern of Ki-ras and p53 mutations appears to distinguish LMP tumors from invasive carcinomas and suggests that they may be separate biological entities.
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PMID:p53 and Ki-ras gene mutations in epithelial ovarian neoplasms. 831 18

Bacteroides heparinolyticus in subgingival plaque was identified using a digoxigenin-labeled whole genomic DNA probe and a polymerase chain reaction (PCR) assay based on 16S rRNA species-specific primers (5'-ATG GTG ATT CCG CAT GGT TTC TCC-3' (base position, 188-212) and 5'-CAA ACT TTC ACA GCT GAC TTA AGC-3' (592-615)). Subgingival specimens obtained by paper points from 3 deep periodontal pockets in each of 113 adults were examined. The DNA probe reacted with all pure isolates tested of B. heparinolyticus and did not react with other oral species tested; the probe showed positive reactions in 74.3% of the patient samples examined. The PCR primers produced the 428 bp species specific amplification product in all B. heparinolyticus test strains and did not reveal detectable amplicons with strains of other subgingival species. The PCR method detected 50 B. heparinolyticus cells dispersed in subgingival plaque. PCR only revealed B. heparinolyticus in 6.2% of the patient samples studied. The higher level of positive specimens with the DNA probe was probably due to false-positive reactions from cross-hybridization with unknown subgingival species. This study suggests that the PCR method amplifying specific 16S rRNA sequences represents an easy and valuable means to detect B. heparinolyticus in subgingival plaque. The low prevalence of subgingival B. heparinolyticus does not incriminate the organism in the etiology of adult periodontitis.
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PMID:Molecular genetic detection of Bacteroides heparinolyticus in adult periodontitis. 859 70

The mutagenic thymidine analog bromodeoxyuridine (BrdUrd) may incorrectly incorporate opposite deoxyguanine in DNA, then pair with deoxyadenosine during subsequent replication. It appears to preferentially target the 3'-G of 5'-NGGN-3' sequences in mammalian cells in culture to induce G-->A transitions. Ras genes should therefore be vulnerable to activation by mutation at glycine codons 12 (GGT) and/or 13 (GGC) by misincorporation of BrdUrd. There is limited evidence that BrdUrd may be carcinogenic or co-carcinogenic in rats: three renal mesenchymal tumors, a tumor known to be associated with activating mutations in the c-K-ras-2 oncogene, were reported in 87 rats treated with BrdUrd alone, while N-nitrosomethylurea (NMU) alone or NMU + BrdUrd resulted in incidences of 12/52 and 26/76, respectively, against a zero incidence in untreated rats. We analyzed renal mesenchymal tumors from rats treated with BrdUrd for mutations in K-ras exons 1 and 2 and compared the prevalence and spectrum of mutations with those found in comparable tumors induced with NMU. DNAs from 22 paraffin-embedded renal mesenchymal tumors from rats treated 12-15 months earlier with BrdUrd (three specimens) or NMU (11 specimens) or both agents sequentially (eight specimens) were amplified by PCR. The base sequence of codons 12-13 and 59-63 of K-ras was determined by the dideoxynucleotide method. Sequencing results were confirmed by allele-specific oligonucleotide hybridization. Two of three tumors that appeared in rats given BrdUrd alone contained both a codon 12 GGT-->GAT transition and a codon 61 CAA-->CTA transversion. One tumor induced by NMU alone also showed a codon 12 GGT-->GAT mutation, while only wild type sequence could be demonstrated in the codon 12-13 region in the remaining ten such tumors. Three NMU-induced tumors also showed codon 61 CAA-->CTA mutations, while the remaining tumors had wild type sequence. While the GGT-->GAT transitions identified in tumors from BrdUrd-treated rats are consistent with BrdUrd mutagenesis by misincorporation, the co-occurrence of CAA-->CTA transversions, the overall low prevalence of mutations, and the lack of any difference in mutation spectrum between tumors induced by NMU and those that occurred in BrdUrd-treated rats suggests that in both groups the mutations that did occur did not result from a direct effect of either agent.
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PMID:K-ras codon 12 and 61 point mutations in bromodeoxyuridine- and N-nitrosomethylurea-induced rat renal mesenchymal tumors. 902 Aug 96


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