Search results for "Cytidine"
showing 10 items of 130 documents
Mechanism and biological role of Dnmt2 in Nucleic Acid Methylation
2016
ABSTRACT A group of homologous nucleic acid modification enzymes called Dnmt2, Trdmt1, Pmt1, DnmA, and Ehmet in different model organisms catalyze the transfer of a methyl group from the cofactor S-adenosyl-methionine (SAM) to the carbon-5 of cytosine residues. Originally considered as DNA MTases, these enzymes were shown to be tRNA methyltransferases about a decade ago. Between the presumed involvement in DNA modification-related epigenetics, and the recent foray into the RNA modification field, significant progress has characterized Dnmt2-related research. Here, we review this progress in its diverse facets including molecular evolution, structural biology, biochemistry, chemical biology,…
A putative antiviral role of plant cytidine deaminases
2014
[Background]: A mechanism of innate antiviral immunity operating against viruses infecting mammalian cells has been described during the last decade. Host cytidine deaminases (e.g., APOBEC3 proteins) edit viral genomes, giving rise to hypermutated nonfunctional viruses; consequently, viral fitness is reduced through lethal mutagenesis. By contrast, sub-lethal hypermutagenesis may contribute to virus evolvability by increasing population diversity. To prevent genome editing, some viruses have evolved proteins that mediate APOBEC3 degradation. The model plant Arabidopsis thaliana genome encodes nine cytidine deaminases ( AtCDAs), raising the question of whether deamination is an antiviral mec…
Blastic plasmacytoid dendritic cell neoplasm: genomics mark epigenetic dysregulation as a primary therapeutic target
2018
Blastic Plasmacytoid Dendritic Cell Neoplasm is a rare and aggressive hematological malignancy currently lacking an effective therapy. To possibly identify genetic alterations useful for a new treatment design, we analyzed by whole-exome sequencing fourteen Blastic Plasmacytoid Dendritic Cell Neoplasm patients and the patient-derived CAL-1 cell line. The functional enrichment analysis of mutational data reported the epigenetic regulatory program as the most significantly undermined (P<.0001). In particular, twenty-five epigenetic-modifiers were found mutated (e.g., ASXL1, TET2, SUZ12, ARID1A, PHF2, CHD8); ASXL1 was the most frequently affected (28.6% of cases). To evaluate the impact of …
Weekly administration of gemcitabine plus docetaxel in patients with advanced breast cancer: a phase 1 study.
2002
<i>Objective:</i> This study was designed to determine the maximum tolerable dose (MTD) of gemcitabine plus docetaxel, both given on a weekly schedule, in patients with pretreated metastatic breast cancer (MBC). <i>Methods:</i> Heavily pretreated patients with MBC, aged 18–75 years with World Health Organization performance status of 0–2 were enrolled. Three escalating weekly doses of docetaxel (30, 35 and 40 mg/m<sup>2</sup>) followed by a weekly fixed dose of gemcitabine, 800 mg/m<sup>2</sup>, were administered on days 1, 8 and 15 of a 28-day cycle. Dose-limiting toxicity (DLT) included grade >3 hematologic toxicity and grade >2 stomat…
Gemcitabine plus nab-paclitaxel until progression or alternating with FOLFIRI.3, as first-line treatment for patients with metastatic pancreatic aden…
2020
Abstract Background Chemotherapy is effective in metastatic pancreatic adenocarcinoma (mPA), but new approaches are still needed to improve patients' survival and quality of life. We have previously published good efficacy and tolerability results on a sequential treatment strategy of gemcitabine followed by an intensified FOLFIRI (5FU+irinotecan) regimen. In the present study, we evaluated the same sequence but replaced gemcitabine by the new gemcitabine + nab-paclitaxel standard first-line combination. Patients and methods We randomised chemotherapy-naive patients with proven mPA, bilirubin levels ≤1.5 upper limit of normal values and performance status 0–2 to alternately receive gemcitab…
Biweekly oxaliplatin combined with oral capecitabine (OXXEL regimen) as first-line treatment of metastatic colorectal cancer patients: a Southern Ita…
2005
Oxaliplatin 100 mg/m(2) iv on day 1, and capecitabine 1,000 mg/m(2) orally bid from day 1 (evening) to day 11 (morning) were administered every 2 weeks (OXXEL regimen) to 38 patients as first-line treatment for metastatic colorectal carcinoma. A total of 318 cycles were administered, with a median of 8 (range, 4-12) cycles per patient. Response rate (RR) was 45% (95% confidence interval (CI), 29%-62%), with 7 complete responses and 10 partial responses; furthermore, 12 patients showed a stable disease, so that a disease control was achieved in 29 (76%) patients. RR was greater among patients with performance status 0 (52%), without weight loss (52%), younger than 65 years (50%), and previou…
Gemcitabine (GEM) plus oxaliplatin, folinic acid, and 5-fluorouracil (FOLFOX-4) in patients with advanced gastric cancer
2005
Abstract BACKGROUND AND AIMS: oxaliplatin in combination with folinic acid (FA) and infusional 5-fluorouracil (5-FU) has shown significant anti-tumor activity in gastric cancer patients (FOLFOX). Previous studies have shown that gemcitabine (GEM), a new fluorinated anti-metabolite, enhances the individual anti-tumor activity of either 5-FU or oxaliplatin. We have therefore designed a multi-center phase II trial in order to test a novel GEM+FOLFOX-4 regimen in patients with metastatic gastric cancer. METHODS: we enrolled 36 patients, 28 males and 8 females, with an average age of 64.4 years (range 37-78), who received bi-weekly treatment with GEM (1,000 mg/m2 on day 1), levo-FA (100 mg/m2 on…
Randomized Multicenter Phase II Trial of Two Different Schedules of Irinotecan Combined with Capecitabine as First-Line Treatment in Metastatic Color…
2004
BACKGROUND The aim of the current randomized Phase II study was to investigate the efficacy and safety of capecitabine combined with irinotecan as first-line treatment in metastatic colorectal carcinoma (CRC). METHODS A total of 140 patients received capecitabine at a dose of 1250 mg/m2 twice daily on Days 2–15 and irinotecan at a dose of either 300 mg/m2 on Day 1 (Arm A) or 150 mg/m2 on Days 1 and 8 (Arm B) every 3 weeks. During the course of the study, enrollment was continued using lower doses of capecitabine (1000 mg/m2 twice daily) and irinotecan (Arm A: 240 mg/m2; Arm B: 120 mg/m2) to improve the safety profile of the combinations. RESULTS Efficacy was evaluable in 134 patients (68 in…
Cisplatin and gemcitabine with either vinorelbine or paclitaxel in the treatment of carcinomas of unknown primary site : results of an Italian multic…
2006
BACKGROUND. To date, the standard treatment for patients who have carcinoma of unknown primary site has not been established. METHODS. In this randomized Phase II study, 66 previously untreated patients (33 patients per arm) with carcinomas of unknown primary site received cisplatin (35 mg/m2) and gemcitabine (1000 mg/m2) with either paclitaxel (70 mg/m2) or vinorelbine (25 mg/m2), and all drugs were administered intravenously on Days 1 and 8 of a 21-day cycle. Twenty-nine patients (44%) presented with ≥2 involved sites. The pathologic diagnosis was mainly adenocarcinoma (48 patients; 72.7%) and squamous carcinoma (7 patients; 10.6%). RESULTS. In the first arm, 16 patients (48.5%) experienc…
Gemcitabine plus metronomic 5-fluorouracil or capecitabine as a second-/third-line chemotherapy in advanced adrenocortical carcinoma: a multicenter p…
2010
Adrenocortical carcinoma (ACC) is a rare neoplasm characterized by poor prognosis. First-line systemic treatments in advanced disease include mitotane, either alone or in combination with chemotherapy. Studies evaluating second-line therapy options have obtained disappointing results. This trial assessed the activity and toxicity of gemcitabine plus metronomic fluoropyrimidines in heavily pretreated advanced ACC patients. From 1998 to 2008, 28 patients with advanced ACC progressing after mitotane plus one or two systemic chemotherapy lines were enrolled. They received a combination of i.v. gemcitabine (800 mg/m2, on days 1 and 8, every 21 days) and i.v. 5-fluorouracil protracted infusion (2…