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Query: UNIPROT:P01034 (
cystatin C
)
3,397
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
We report 8 newly established gastric-carcinoma cell lines (SNU-216, 484, 520, 601, 620, 638, 668, 719) from Korean patients. Morphologic study was carried out using light and electron microscopes. CEA, alpha FP, and CA 19-9 and TPA in supernatant and in cell lysate were measured by radioimmunoassay. p53 and c-Ki-ras gene mutations were screened and confirmed by sequencing. The cell lines, derived from tumors with moderate differentiation, grew as a diffuse monolayer, and those from tumors with poor differentiation and minimal desmoplasia grew exclusively as non-adherent. Out of the 8 gastric-cancer cell lines, 5 had detectable levels of CEA both in supernatant and in cell lysate; there was no expression or secretion of alpha FP in these cells; 4 cell lines showed high levels of CA 19-9 in cell pellets. All cell lines except SNU-484 had high concentrations of TPA both in cell lysate and in supernatants. p53 mutation was found in 6 cell lines (75%): 2 (SNU-216 and SNU-668) had mutations in exon 6, and other 3 in exon 8. The c-Ki-ras mutation was found in 2 cell lines (25%), SNU-601 and SNU-668. The former showed
GGT
-to-GAT transition mutation at codon 12, while the latter showed
CAA
-to-AAA transversion mutation at codon 61. DNA profiles using restriction endonuclease HinfI and polymorphic DNA probes ChdTC-15 and ChdTC-114 showed different unique patterns; which suggests that these cell lines are unique and not cross-contaminated. We believe that the newly characterized gastric-cancer cell lines presented in this paper will provide a useful in vitro model for studies related to human gastric cancer.
...
PMID:Establishment and characterization of human gastric carcinoma cell lines. 903 53
Genetic analysis has demonstrated complete linkage between the human thiazide-sensitive sodium chloride cotransporter gene (NCCT or TSC) and Gitelman's syndrome (GS). Several genomic NCCT mutations have been reported. This study was performed to determine whether peripheral blood mononuclear cells (PBMC) express NCCT mRNA and whether defective PBMC NaCl cotransport could be demonstrated in GS. PBMC were isolated from two brothers with GS, their parents, and healthy control subjects. Northern analysis revealed that NCCT mRNA is expressed in PBMC. The sequence of full-length NCCT cDNA amplified from normal PBMC was identical to human renal NCCT cDNA. Two different mutations were detected in the patients' NCCT cDNA (compound heterozygote). In cDNA derived from the patient's maternal allele, exon 24 was deleted, resulting in a premature stop codon (after amino acid 920). cDNA derived from the patient's paternal allele had an additional 119-bp insertion between exons 3 and 4, generating a premature stop codon (after amino acid 187). The patient's genomic DNA had a previously described 5' splice site mutation in intron 24,
GGT
--> GTT (maternal allele), and a new 3' splice site mutation in intron 3, CAG -->
CAA
(paternal allele), which resulted in the activation of a nearby cryptic splice site in intron 3. The latter mutation was not present in 300 normal chromosomes. To determine the functional significance of these findings, chlorothiazide-inhibitable 22Na uptake was measured in PBMC from control subjects, the parents, and the patients with GS in the presence of bumetanide. In control PBMC, chlorothiazide inhibited 22Na uptake by approximately 9%. PBMC from the two patients with GS failed to respond to chlorothiazide. These results demonstrate that PBMC can be used for mutational analysis of NCCT mRNA in patients with GS. Furthermore, functional evidence is provided that the underlying cause of GS is defective NCCT NaCl cotransport.
...
PMID:Peripheral blood mononuclear cells express mutated NCCT mRNA in Gitelman's syndrome: evidence for abnormal thiazide-sensitive NaCl cotransport. 959 79
Scid mice, which have a defect in the capacity to repair DNA double-strand breaks, were highly prone to the induction of thymic lymphomas after exposure to ionizing radiation; approximately 70% of mice developed lymphomas within 1 year after exposure to 1-3 Gy, whereas approximately 20% of unirradiated control mice developed lymphomas. To gain information on the possible role of Ras activation in development of thymic lymphomas in scid mice, we have examined both the frequency and the spectrum of Kras and Nras mutations in spontaneous and radiation-induced lymphomas. Neither activated Kras nor Nras genes were detected in spontaneous lymphomas, while Kras mutations increased in a dose-dependent manner in radiation-induced lymphomas. However, Kras mutations were infrequent (6% in lymphomas in mice exposed to 1 Gy, 12.5% in those exposed to 2 Gy, 16.7% in those exposed to 3 Gy), and no mutations were detected in Nras genes, suggesting that Ras mutation was not significantly involved in the development of thymic lymphomas in scid mice. Analysis of the spectrum of Kras mutations demonstrated unique mutations in both codons 13 (GGC to GAC) and 61 (
CAA
to CTA) in addition to the commonly identified substitution of GAT for
GGT
in codon 12 of Kras.
...
PMID:Low frequency of Ras gene mutation in spontaneous and gamma-ray-induced thymic lymphomas of scid mice. 995 98
We have analyzed the effect of polychlorinated biphenyls (PCB, Kanechlor-400) on 1-nitropyrene (1-NP) induced lung tumor. Male A/J mice (6 weeks old) were used for the experiment. A total of 2.5 mg/kg PCB was administered intraperitoneally (PCB group), a total of 0.38 mmol/kg 1-NP was administered intraperitoneally for 17 times (1-NP group), PCB was administered followed by i.p. injection of 1-NP (PCB + 1-NP group), and only vehicle was administered (control group). The lung lesions induced were examined 18 weeks after the final treatment with 1-NP or vehicle. In control group, no neoplastic lesion in the lung was induced. In PCB group, only one lesion with adenoma was induced. In 1-NP group, various kinds of lung neoplastic lesions including hyperplasia, adenoma and adenocarcinoma were induced. In PCB + 1-NP group, both the number and size of tumors induced were significantly more than those in 1-NP group. In addition, the number of adenocarcinoma formed was more in PCB + 1-NP group than in 1-NP group. Each lesion was microdissected to collect and analyze DNA of the targeted tissue. K-ras gene mutation was detected in part of adenoma lesions and all the carcinoma lesions. The mutation was found in either 1-NP or PCB + 1-NP group, but not in control and PCB group. The pattern of K-ras mutation was
CAA
to CGA in codon 61 or
GGT
to GAT in codon 12. There was no difference in the pattern of K-ras mutation despite of the pretreatment with PCB. Although the present data are from small sample size, it was suggested that PCB may promote (but not initiate) 1-NP induced lung tumorigenesis, and may not induce K-ras mutation directly in the experimental system.
...
PMID:[Effect of PCBs on mouse lung tumorigenesis induced by 1-nitropyrene: a preliminary report]. 1039 79
The Donryu rat has been found to have a high incidence of spontaneous uterine endometrial carcinomas. Moreover the histologic findings, biological nature and pathogenesis of these rat tumors appear similar to those in humans. To determine if the incidence of H- and K-ras gene mutations in these rat tumors is similar to that in human endometrial cancers, we isolated DNA samples from 2 atypical hyperplasias, 5 simple or complex hyperplasia without atypia, 9 adenocarcinomas and 7 histologically normal tissues, amplified exons 1 and 2 of the H- and K-ras genes by PCR and hybridized the products with allele specific oligonucleotide probes. K-ras point mutations were observed in 1/2 of the atypical hyperplasia (codon 12:
GGT
-->GTT) and 3/9 of the carcinoma (codon 12:
GGT
-->GAT,
GGT
-->AGT, codon 61:
CAA
-->CAC), while they were not detected in 7 of the normal tissues and in 5 of the simple or complex hyperplasia without atypia. H-ras point mutations were not detected in any of these DNA samples. These frequencies in this rat model are similar to those in humans. The absence of K-ras mutations from simple and complex hyperplasia tissue samples suggests that these mutations are associated with cytological atypia. Our findings suggest that alterations in the K-ras gene may be one of the important initiating event in endometrial carcinogenesis in some of the Donryu rat, like the human.
...
PMID:K-ras point mutations in spontaneously occurring endometrial adenocarcinomas in the Donryu rat. 1077 52
Preconceptional exposure of male NIH Swiss mice to chromium(III) chloride resulted in increased incidence of neoplastic and non-neoplastic changes in their progeny, including lung tumors in females [Toxicol. Appl. Pharmacol. 158 (1999) 161-176]. Since mutations in the K-ras protooncogene are frequent, early changes in mouse lung tumors, we investigated possible mutational activation of this gene as a mechanism for preconceptional carcinogenesis by chromium(III). These offspring had lived until natural death at advanced ages (average 816+/-175 days for controls, 904+/-164 for progeny of chromium-treated fathers). Mutations of K-ras, analyzed by single-strand conformation polymorphism and sequencing, were, in codon 12, wild type
GGT
(glycine), to GAT (aspartic acid); to GTT (valine); and to CGT (arginine); and in codon 61, wild-type
CAA
(glutamine), to CGA (arginine). K-ras mutation frequencies in lung tumors were very similar in control progeny (4/14) and in progeny of chromium-treated fathers (5/15). Thus, germline mutation or tendency to spontaneous mutation in K-ras does not seem to be part of the mechanism of preconceptional carcinogenesis here. However, an additional interesting observation was that K-ras mutations were much more frequent in lung carcinomas (8/16) than in adenomas (1/13) (P=0.02), for all progeny combined. This was not related to age of the tumor-bearing mice or the size of the tumors. K-ras mutations may contribute to malignant tumor progression during aging, of possible relevance to the putative association of such mutations with poor prognosis of human lung adenocarcinomas.
...
PMID:K-ras mutations in mouse lung tumors of extreme age: independent of paternal preconceptional exposure to chromium(III) but significantly more frequent in carcinomas than adenomas. 1115 72
Genetic variations in the locus encoding the transporter associated with antigen processing, subunit 1 (TAP1), were systematically studied using samples from Caucasians, Africans, Brazilians, and compared with data from chimpanzees. PCR-amplified genomic sequences corresponding to the 11 exons were analyzed by single-strand conformation polymorphism (SSCP) and sequencing. Six nonsynonymous and 2 synonymous single nucleotide polymorphisms (SNPs) were found to be common in one ethnic group or another, and they involved codons 254 (Gly-GGC/Gly-
GGT
) in exon 3, 333 (Ile-ATC/Val-GTC) in exon 4, 370 (Ala-GCT/Val-GTT) in exon 5, 458 (Val-GTG/Leu-TTG) in exon 6, 518 (Val-GTC/Ile-ATC) in exon 7, 637 (Asp-GAC/Gly-GGC), 648 (Arg-CGA/Gln-
CAA
) and 661 (Pro-CCG/Pro-CCA) in exon 10. At each SNP site the sequence listed first was predominant in all ethnic groups. Several SNPs segregated on the same chromosome regardless of populations and species. Together, the SNPs produced 5 major human TAP1 alleles, 4 of which matched the officially recognized alleles *0101, *02011, *0301, and *0401; the 5th allele differed from each of those by at least 4 SNPs. Overall, TAP1*0101 was the predominant allele in all ethnic groups, with frequencies ranging from 0.667 in Zambians to 0.808 in US Caucasians. The TAP1*0401 frequency showed the greatest difference between Africans (0.221-0.254) and Caucasians (0.033), with Brazilians (0.058) fitting in the middle. Consistent with earlier work based on Caucasians and gorillas, *0101 appeared to be the newest human TAP1 allele, suggesting a dramatic spread of *0101 into all human populations examined. Characterization of TAP1 polymorphisms allowed the design of a PCR-based genotyping scheme that targeted 7 SNP sites and required 2 separate genotyping techniques.
...
PMID:TAPI polymorphisms in several human ethnic groups: characteristics, evolution, and genotyping strategies. 1125 43
Scid mice are defective in the ability to repair DNA double strand breaks and, as a consequence, their cells are radiosensitive. Further, they have been shown to be prone to develop thymic lymphomas (TLs) after small doses of ionizing radiation. Little is known, however, on the role of scid mutation in chemical carcinogenesis. To determine if scid mutation increased predisposition to chemical carcinogenesis, we examined both the susceptibility of scid mice to N-ethyl-N-nitrosourea (ENU)-induced lymphomagenesis and the involvement of ras gene activation. Adult female mice at 8 weeks of age were given ENU in their drinking water at 400 ppm for 2-10 weeks. Contrary to expectations, we observed a two to three-fold reduction in TL development in the scid mice. The highest incidence was achieved by ENU treatment for 8 weeks for scid and wild-type C.B-17 mice, of 42 and 85%, respectively (P<0.05). We investigated whether this was attributable to the usage of the ras mutation pathway. There was, however, no significant difference in the frequency and spectrum of K-ras mutation between the scid and wild-type C.B-17 mice. Most of the K-ras mutations were either
GGT
to GAT transition in codon 12 (11/23: 48%) or
CAA
to CCA transversion in codon 61 (8/23: 35%) that was independent of scid background. The incidence of N-ras mutation was very low. These results indicate that scid mice are less susceptible to ENU-induced lymphomagenesis and ras gene mutation frequently occurs in both scid and wild-type C.B-17 mice.
...
PMID:Reduced sensitivity to and ras mutation spectrum of N-ethyl-N-nitrosourea-induced thymic lymphomas in adult C.B-17 scid mice. 1151 30
Although the effects of polychlorinated biphenyls (PCBs) on human lung carcinogenesis are suggested from the massive PCBs poisoning that occurred in Japan designated "Yusho," the detailed molecular mechanism are unknown. 1 nitropyrene (1-NP), an ubiquitous and abundant environmental pollutant, is known to be detected in lung tissues derived from patients with lung cancer in Japan, and its relation to lung carcinogenesis is also suggested. We investigated the effects of PCBs (Kanechlor-400) on 1-NP-induced lung tumorigenesis in A/J mice. PCBs were administered intraperitoneally followed by ip injection of 1-NP. The lung lesions were examined 18 weeks after the final treatment. In the control group, no neoplastic lesions were induced in the lung. In the PCB group, preneoplastic lesions such as hyperplasia and adenoma were induced in 2/10 (20%) mice. In 1-NP group and in PCB + 1-NP group, lung lesions including adenocarcinoma were induced in 16/20 (80%) and 13/13 (100%) mice, respectively. Both the number and the size of tumors in PCB + 1-NP group were significantly greater than those in 1-NP group. K-ras gene mutation,
CAA
to CGA in codon 61 or
GGT
to GAT in codon 12, was found in either 1-NP group or PCB + 1-NP group but not in the PCB group. There was no difference in the pattern of K-ras mutation associated with the pretreatment with PCBs. These results suggest that PCBs promote 1-NP-induced lung tumorigenesis and may support, at least in part, the mechanism of the high incidence of lung cancer in patients with Yusho.
...
PMID:Polychlorinated biphenyls promote 1-nitropyrene-induced lung tumorigenesis without the induction of K-ras gene mutation in A/J mice. 1174 53
Allele-specific competitive blocker PCR (ACB-PCR) is a sensitive allele-specific amplification method in which preferential amplification of the mutant allele occurs by using a primer that has more mismatches to the wild-type allele than to the mutant allele (mutant-specific primer, MSP). Additionally, a non-extendable primer with more mismatches to the mutant allele than to the wild-type allele (blocker primer, BP) competes with the MSP for binding to the wild-type allele, thereby reducing background amplification from the wild-type allele. ACB-PCR primer design is largely dependent upon the basepair substitution being measured, making it unclear if this method is broadly applicable. In an earlier study, an H-ras codon 61
CAA
-->AAA mutation had been detected by ACB-PCR at a sensitivity of 10(-5). In this study, ACB-PCR was applied to two human K-ras codon 12 mutations:
GGT
-->GTT and
GGT
-->GAT. The method was optimized by systematically altering the concentrations of Perfect Match PCR Enhancer, MSP, BP, and dNTPs. For each mutation, mutant fractions as low as 10(-5) were detected, indicating that this assay can be used on a variety of base substitution mutations. In addition, the results suggest that the 3'-terminal mismatches between the MSP and wild-type allele may be used to predict the ACB-PCR conditions that will be appropriate for the detection of other base substitution mutations. The range of concentrations for each of these components is narrow, making this method relatively easy to apply to additional mutational targets.
...
PMID:Detection of rare K-ras codon 12 mutations using allele-specific competitive blocker PCR. 1203 22
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