Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

---

Query: EC:2.6.1.44 (AGT)
770 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recently, there have been a few case reports of invasive ductal adenocarcinoma (IDC) developed in the remnant pancreas after partial pancreatectomy for intraductal papillary-mucinous neoplasm (IPMN). It is necessary to clarify their histogenetic relationships among two sporadic tumors and their surrounding duct epithelium and it would be more reliable if genetic analysis is added to the conventional histology. We report a 76-year-old woman who received pancreaticoduodenectomy for IPMN with a focal in situ carcinoma (IPMC), which was transitional to the surrounding duct epithelium with papillary proliferation and a wide variety of dysplasia. Nine years after the operation, she died of IDC in the remnant pancreatic body and its surrounding duct epithelium consisted of hyperplastic mucous cells with slight-mild dysplasia. Analysis of K-ras mutation at codon 12 (wild-GGT) by direct sequencing after polymerase chain reaction indicated that their transitioning patterns differed from each other: CGT in IPMC; no mutation in the mildly dysplastic duct epithelium around IPMC; GAT in IDC of the remnant pancreas; and AGT in mucous cell hyperplasia with mild dysplasia close to the IDC. This is the first report in which the DNA sequence of K-ras mutation was determined for the two sporadic pancreatic cancers and surrounding duct changes. The following two suggestions are made: (1) the cell-origin might have differed between the two types of cancer (IDC and IPMC); and (2) no precursor lesion toward IDC or IPMC was identified in their surrounding duct epithelium.
...
PMID:Invasive ductal adenocarcinoma of the remnant pancreatic body 9 years after resection of an intraductal papillary-mucinous carcinoma of the pancreatic head: a case report and comparison of DNA sequence in K-ras gene mutation. 1207 25

The aim of this study was to clarify the histogenesis of Barrett's cancer. First, 28 lesions of the super-minute dysplasia <or= 1 mm in diameter were detected by pathological examinations for Barrett's esophagus. Secondly, the K-ras codon 12 mutations in these super-minute neoplasias of the Barrett's esophagus were examined by DNA extraction using a microdissection. It was found that seven of 28 (25%) super-minute dysplasia lesions in the Barrett's esophagus showed K-ras mutation, and were a single mutation, with AGT being detected in three lesions and GAT being detected in four lesions. Also, these dysplasia lesions could be divided into two groups according to p53-LI. Two among three lesions with p53-LI over 90%, which were considered to be morphologically high grade dysplasia or intramucosal adenocarcinoma, showed K-ras mutations (both lesions: GGT-->AGT), and 5 among 25 lesions with an average p53-LI of 58%, which were considered to be morphologically low grade dysplasia, showed K-ras mutation (four lesions: GGT-->GAT, 1 lesion: GGT-->AGT). This current study shows that some dysplasia lesions have K-ras mutations in their initial condition, whether these atypical tubule lesions are low grade dysplasia or high grade dysplasia (intramucosal adenocarcinoma), and supports the dysplasia-carcinoma sequence in the histogenesis of Barrett's cancer and synchronously suggests that there is a different route to it.
...
PMID:K-ras codon 12 mutations of the super-minute dysplasia in Barrett's esophagus by DNA extraction using a microdissection method. 1464 12

The aim of this study was to identify K-ras mutations as marker for isolated tumor cells in liver, lymph node, and bone marrow specimens of colorectal cancer patients. To detect these, a PCR-RFLP assay was used with a sensitivity exceeding that of routine histopathology by at least 1 order of magnitude. In addition, the ratio of mutated versus wild-type alleles was determined by an internal standard. Of 199 patients, 74 (37.5%) were found to bear a K-ras-positive tumor. Of these, 60 (81%) were mutated in codon 12 and 14 (19%) in codon 13 (P < 0.001). In addition, 14 organs were found K-ras positive, 13 of which were from 12 patients with a K-ras-positive tumor (16%) and 1 from a patient with a K-ras-negative tumor (0.8%). Eight patients exhibited liver involvement and 6 showed lymph node involvement. Remarkably, no bone marrow specimen was found K-ras positive (P < 0.017 versus liver involvement). Sequence analysis of tumor DNA revealed that GGT (Gly) was replaced by GAT (Asp; 35%), GTT (Val; 32%), AGT (Ser; 13%), GCT (Ala; 10%), TGT (Cys; 8%), and CGT (Arg; 2%) for codon 12, and by GAC (Asp) as the only type of mutation for codon 13. In colorectal carcinomas the ratio of K-ras mutated versus wild-type alleles ranged over 4 orders of magnitude (10(0)-10(-4), median: 10(-2)) and was correlated with both, residual tumor load (R1/2; P = 0.028) and distant metastasis (M1; P = 0.057). These results show that detection of K-ras mutated alleles by PCR-RFLP in patients with colorectal carcinoma may aid in the identification of isolated tumor cells. High ratios of K-ras alleles were correlated with certain negative prognostic parameters (R,M). In accord with its function as a primary filter for colorectal carcinoma cells, the liver was more often contaminated with K-ras-positive cells than bone marrow.
...
PMID:Detection of isolated tumor cells by polymerase chain reaction-restriction fragment length polymorphism for K-ras mutations in tissue samples of 199 colorectal cancer patients. 1476 87

ABSTRACTS: BACKGROUND: The carcinogenesis of colorectal cancer has been accepted by a model for a cascade of genetic alterations, named the adenoma-carcinoma sequence. In order to elucidate the carcinogenesis of the colorectal cancer more clearly, the genetic abnormalies of the non-neoplastic mucosal epithelium of the colon and rectum should be investigated. It has been speculated that colonic Paneth cell metaplasia (PaM) is one of the pre-neoplastic mucosa of colonic cancer. Therefore, we studied the propria mucosa of the right colon with PaM from the standpoints of the frequency of the K-ras codon 12 mutations (K-ras), which is initial genetic abnormality in colorectal cancer, and the loss of heterozygosity of microsatellite markers (LOH-MS), which has a relationship to development of colorectal cancer. METHODS: Fifty-two regions with PaM histopathologically from 12 surgically resected right colon specimens were studied. DNA extraction of the colonic mucosa with PaM was obtained using a microdissection method, and the frequency of the K-ras of PaM was investigated by enriched polymerase chain reaction-enzyme linked mini-sequence assay, and the frequency of the LOH-MS (D2S123, D17S250 and D5S346) of PaM was examined by high resolution fluorescenced labeled PCR primers. RESULTS: K-ras mutation was detected in fifteen regions among 52 PaM (28.9%). All mutations were a single mutation and GGT changed to AGT in eleven and GAT in four. LOH-MS were detected in twenty-one regions among 52 PaM (40.4%) (D2S123: 35.4%, 17/48 regions, D17S250: 13.7%, 7/51 regions, and D5S346: 0%, 0/52 regions). No K-ras mutations and LOH-MS were detected in the controls (Colorectal mucosa with no PaM). CONCLUSIONS: Colonic mucosa with Paneth cell metaplasia may be one of the pre-neoplastic mucosa in the development of the colonic epithelial neoplasia.
...
PMID:Colonic Paneth cell metaplasia is pre-neoplastic condition of colonic cancer or not? 1570 98

Acephala applanata gen. et sp. nov. is described. A. applanata is a dark-septate endophyte (DSE) of conifer roots and belongs to the Phialocephala fortinii species complex. Several genetic markers, including isozymes, inter-simple-sequence-repeat (ISSR) fingerprints, single-copy restriction fragment length polymorphisms (RFLP) and sequences of the internal transcribed spacers (ITS), let us unambiguously separate isolates of A. applanata from isolates of P. fortinii s.l. and other dark-septate endophytes. Alleles at four RFLP loci and two fixed nucleotides in the ITS region were diagnostic for A. applanata. One of the fixed nucleotides resulted in the addition of an Afa I restriction site. PCR amplification with primers prITS4 and the newly developed primer PF-ITS_F (ACT CTG AAT GTT AGT GAT GTC TGA GT) and restriction digestion with Afa I yielded three fragments (203 bp, 117 bp, 56 bp) in A. applanata but only two (260 bp and 117 bp) in P. fortinii s.l. Population differentiation (GST) between A. applanata and other cryptic species of P fortinii was pronounced, and the index of association (IA) did not deviate significantly from zero, showing that recombination occurs or had occurred in A. applanata. Although isolates of A. applanata never were observed to sporulate, it can be distinguished morphologically from P fortinii s.l. by the scarcity of aerial mycelium, significantly slower growth and denser mycelium on cellophane overlaid on water agar. These phenotypic characteristics, combined with diagnostic RFLP alleles and/or PCR-RFLP of the ITS fragment with the fixed Afa I restriction site, unequivocally allow identification of A. applanata.
...
PMID:Molecular and phenotypic description of the widespread root symbiont Acephala applanata gen. et sp. nov., formerly known as dark-septate endophyte type 1. 1639 52

Genomic DNA of Blastocystis isolates released into 0.1% Triton X-100 was suitable for amplification and yielded similar results as the genomic DNA extracted with standard kit. The specific B. hominis primers (BH1: GCT TAT CTG GTT GAT CCT GCC AGT and BH2: TGA TCC TTC CGC AGG TTC ACC TAC A) successfully produced the PCR product of about 1,770 bp with all the 7 Blastocystis isolates tested. The restriction fragment length polymorphism (RFLP) patterns yielded by 13 out of 25 restriction endonucleases showed that the 7 isolates could be grouped into 4 subgroups: subgroup-1 consisted of isolate C; subgroup-2 of isolates H4 and H7; subgroup-3 of isolates KP1, Y51 and M12; and subgroup-4 of isolate 27805. The differences between subgroups manifested as clear-cut RFLP patterns. A common band of 230 bp was revealed by Eco R1 in all the Blastocystis isolates tested. The band of about 180 bp was revealed by Alu I, differentiated symptomatic from asymptomatic isolates of this parasite, and might indicate the pathogenicity of this parasite.
...
PMID:Restriction enzyme digestion analysis of PCR-amplified DNA of Blastocystis hominis isolates. 1861 39

Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) was widely accepted as a pivotal molecule in downregulating T-cell mediated immune responses. In this study we investigated the polymorphisms which would impact the CTLA-4 gene expression and function to assess the association with the risk of gastric cancer. 205 gastric cancer patients and 262 healthy controls were included in the case-control study. PCR and restriction fragment length polymorphism (RFLP) methods were performed to identify the +49A/G and promoter -1661A/G polymorphisms. The promoter -1772T/C polymorphism was detected by PCR amplification refractory mutation system (ARMS) technique. A significant difference was observed between case and control groups. The frequency of +49A/G polymorphism AG and -1661A/G polymorphism GG genotype were significantly higher in patients than in controls (OR = 2.15, OR = 1.88, respectively). No significant difference was found in the allelic frequency of -1772T/C polymorphism between cases and controls (P = 0.478). By the haplotype analysis, logistic regression showed the frequency of haplotype A (GAT) and D (AGT) in the case group revealed significant difference compared with in control group (OR = 2.00, P < 0.001; OR = 1.62, P = 0.043, respectively). Our findings implied the genetic variations within CTLA-4 gene would be a critical risk factor to the susceptibility of gastric cancer.
...
PMID:Association of cytotoxic T lymphocyte-associated antigen-4 gene haplotype with the susceptibility to gastric cancer. 1968 78

Patients with biliary tract carcinoma have a poor prognosis. Early detection efforts are urgently needed to ameliorate the dismal prognosis for these patients. Mutations of the KRAS2 gene are one of the most common genetic aberrations in this cancer. In this study, we used LigAmp, an ultrasensitive technology for detecting point mutations, to analyze KRAS2 mutations in patients with a variety of neoplastic and non-neoplastic pancreatobiliary diseases. DNA was isolated from 64 samples, including 44 bile samples and 20 serum samples. Oligonucleotides specific for KRAS2 G35A (GAT, G12D), G35T (GTT, G12V), and G34A (AGT, G12S) mutations were used. KRAS2 mutations were detected in 14 of 16 (87.5%) neoplastic bile samples and in 9 of 28 (32.1%) non-neoplastic bile samples. However, the mutation levels were significantly lower in the non-neoplastic bile (median = 0.4%) compared with those in the neoplastic bile (median = 5.1%). KRAS2 mutations were also detected in 9 of 11 (81.8%) serum samples from patients with biliary tract carcinoma, which was further confirmed by cloning BstN1-refractory PCR products and DNA sequencing. However, KRAS2 mutations were not present in the sera from eight patients with benign pancreatobiliary diseases. These data demonstrate that KRAS2 mutations are detectable in both bile and serum using LigAmp. This technology has the potential for early biliary tract carcinoma detection and possibly for residual disease monitoring post-therapy.
...
PMID:Ultrasensitive detection of KRAS2 mutations in bile and serum from patients with biliary tract carcinoma using LigAmp technology. 1981 96

Activation of KRAS oncogene has been implicated in colorectal carcinogenesis. KRAS mutations can be detected in more than 30% of all patients with colorectal cancer (CRC). Most recently, regimens that include anti-epidermal growth factor receptor (EGFR) targeted antibodies, cetuximab and panitumumab, for metastatic CRC have been developed. Several recent studies have shown that patients with KRAS mutations in codons 12 and 13 in metastatic CRC do not benefit from anti-EGFR therapy. With the aim to determine KRAS status as predictive biomarker, 7 known mutations ofKRAS gene in codons 12 or 13 on 44 CRC samples were tested. After DNA extraction from paraffin-embedded tumor tissue blocks, KRAS mutations were analysed using quantitative real-time PCR with internationally certified method, for the first time in Croatia. Mutations were detected in 12 tumor samples: five patients with Gly12Val (GGT>GTT), three with Gly12Asp (GGT>GAT), two patients with Gly13Asp (GGC>GAC), one patient with Gly12Ser (GGT>AGT) and one with Gly12Cys (GGT>TGT) mutation in tumor. Our data about KRAS mutational status in the sample of Croatian population diagnosed with CRC have shown that incidence of KRAS mutation is 27%, which is consistent with results already reported worldwide. The final result must be a proper selection of the correct therapy with EGFR inhibitors for the patients with CRC which is critical for improving clinical outcomes, unnecessary toxicities, side effects and financial cost.
...
PMID:[The role of KRAS gene mutation testing in colorectal cancer--a predictive biomarker of response to EGFR inhibitors therapy]. 2232 97

Fusarium oxysporum is a soil-borne fungus that causes vascular wilts in a wide variety of plant species. Basil is recognized as an ecological niche for Fusarium oxysporum f.sp. basilici (FOB) and this fungus is now present in most countries where basil is cultivated. The rapid identification of the species affecting basil plants is necessary to define a successful method for crop protection. The aim of this study was to develop a PCR method for the rapid detection of Fusarium oxysporum f. sp. basilici in substrates. The specificity of the primers used was tested using the DNA extracted directly from substrate samples. Fusarium oxysporum f.sp. basilici was artificially inoculated with decreasing amounts in a commercial substrate (sphagnum peat moss) and in a mixture with 40% of municipal compost, after steam disinfestation. Basil seeds (cv. Fine verde) were sown in pots that were laid on a bench in the greenhouse. At time 0 and after 7, 14 and 21 days from the inoculation, substrate and root samples were collected and prepared for microbial analysis and for the DNA extraction. DNA extraction was carried out using NucleoSpin Soil Kit (Macherey-Nagel, Germany). PCR amplification for the specific detection was carried out using primer sets Bik 1 (5'-ATT CAA GAG CTA AAG GTC C-3') and Bik 4 (5'-TTT GAC CAA GAT AGA TGC C-3') for the first PCR, while primers Bik 1 + Bik 2 (5'-AAA GGT AGT ATA TCG GAG G-3') for the nested PCR to increase detection sensitivity. Disease incidence was also assessed 21 days after seeding. The results showed the presence of amplified fragments of the expected size when the concentration of F. oxysporum f.sp. basilici was at least 3.5 Log CFU g(-1) by using DNA extract directly from substrate, before roots were infected by the pathogen. The detection of Fusarium oxysporum f. sp. basilici by PCR method developed in this study is certainly simple and fast and can be useful for its reliable detection in substrate samples, but not to guarantee that the substrate is totally free of pathogens.
...
PMID:Detection of Fusarium oxysporum f.sp. basilici in substrates and roots by PCR. 2515 41


<< Previous 1 2 3 Next >>

---