tetrahydrouridine and Neoplasms

Inhibitors of DNA (cytosine-5)-methyltransferases (DNMT) are active antineoplastic agents. We conducted the first-in-human phase I trial of 5-fluoro-2'-deoxycytidine (FdCyd), a DNMT inhibitor stable in aqueous solution, in patients with advanced solid tumors. Objectives were to establish the safety, maximum tolerated dose (MTD), pharmacokinetics, and pharmacodynamics of FdCyd + tetrahydrouridine (THU).. FdCyd + THU were administered by 3 h IV infusion on days 1-5 every 3 weeks, or days 1-5 and 8-12 every 4 weeks. FdCyd was administered IV with a fixed 350 mg/m(2)/day dose of THU to inhibit deamination of FdCyd. Pharmacokinetics of FdCyd, downstream metabolites and THU were assessed by LC-MS/MS. RBC γ-globin expression was evaluated as a pharmacodynamics biomarker.. Patients were enrolled on the 3-week schedule at doses up to 80 mg/m(2)/day without dose-limiting toxicity (DLT) prior to transitioning to the 4-week schedule, which resulted in an MTD of 134 mg/m(2)/day; one of six patients had a first-cycle DLT (grade 3 colitis). FdCyd ≥40 mg/m(2)/day produced peak plasma concentrations >1 µM. Although there was inter-patient variability, γ-globin mRNA increased during the first two treatment cycles. One refractory breast cancer patient experienced a partial response (PR) of >90 % decrease in tumor size, lasting over a year.. The MTD was established at 134 mg/m(2) FdCyd + 350 mg/m(2) THU days 1-5 and 8-12 every 4 weeks. Based on toxicities observed over multiple cycles, good plasma exposures, and the sustained PR observed at 67 mg/m(2)/day, the phase II dose for our ongoing multi-histology trial is 100 mg/m(2)/day FdCyd with 350 mg/m(2)/day THU.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Chromatography, Liquid; Deoxycytidine; DNA (Cytosine-5-)-Methyltransferases; Dose-Response Relationship, Drug; Female; gamma-Globulins; Humans; Infusions, Intravenous; Male; Maximum Tolerated Dose; Middle Aged; Neoplasms; Tandem Mass Spectrometry; Tetrahydrouridine; Treatment Outcome

Between 82.8% and 92.5% of participants in any BMI group were responders by AS, and between 91.3% and 100% were responders by BBPS in the right colon. Efficacy was consistent across BMI groups, with no clear trends. Greater than 83% of participants in any BMI group found the preparation 'easy' or 'acceptable' to ingest, and the majority (>58%) rated SPMC oral solution as 'better' than a prior bowel preparation. In all BMI groups, safety data were similar to the overall cohort. Commonly reported, drug-related, treatment-emergent AEs were, by ascending BMI group, nausea (1.1%, 5.3%, 1.0%, 5.7%, and 0%) and headache (1.1%, 4.1%, 1.0%, 5.7%, and 0%).. Ready-to-drink SPMC oral solution had consistent, good quality colon cleansing, and favorable tolerability among participants of all BMI groups.. NCT03017235.. The pretreatment serum AST/ALT ratio predicts poor disease outcome and response rate in patients with advanced PDAC treated with gemcitabine/nab-paclitaxel and might represent a novel and inexpensive marker for individual risk assessment in the treatment of pancreatic cancer.. Of the 98 patients included in the study, 58 had CR (59%), 28 had PR (29%), and 12 patients had NR (12%). The percent splenic tissue embolized was significantly greater in the CR group compared to the PR group (P = 0.001). The percent volume of splenic tissue embolized was linearly correlated with the magnitude of platelet increase without a minimum threshold. At least one line of chemotherapy was successfully restarted in 97% of patients, and 41% of patients did not experience recurrence of thrombocytopenia for the duration of their survival. The major complication rate was 8%, with readmission following initial hospitalization for persistent "post-embolization syndrome" symptoms the most common.. In cancer patients with hypersplenism-related thrombocytopenia, PSAE is a safe intervention that effects a durable elevation in platelet counts across a range of malignancies and following the re-initiation of chemotherapy.. Postoperative CRP elevation was a better predictor of prognosis in patients with gastric cancer than the occurrence of intra-abdominal infectious complications.. In clinical practice, mixed-species malaria infections are often not detected by light microscopy (LM) or rapid diagnostic test, as a low number of parasites of one species may occur. Here, we report the case of an 8-year-old girl migrating with her family from Afghanistan with a two-species mixed infection with

Topics: 3-Hydroxybutyric Acid; Acetazolamide; Acrylates; Administration, Intravenous; Adolescent; Adult; Aerosols; Afghanistan; Aflatoxin M1; Agaricales; Aged; Aged, 80 and over; Agricultural Irrigation; Air Pollutants; alpha-L-Fucosidase; Amino Acid Sequence; Androgen Antagonists; Animals; Antibodies, Bacterial; Antigens, Bacterial; Antineoplastic Agents; Antioxidants; Apoptosis; Artifacts; Autophagy; B7-H1 Antigen; Bacterial Proteins; Bacterial Typing Techniques; Bariatric Surgery; Base Composition; Bayes Theorem; Bile; Bioelectric Energy Sources; Biosensing Techniques; Body Mass Index; Brain; Brazil; Breast Neoplasms; Bufo arenarum; Burkholderia; C-Reactive Protein; Cadmium; Carbon Compounds, Inorganic; Carbon-13 Magnetic Resonance Spectroscopy; Carbonic Anhydrase Inhibitors; Carbonic Anhydrases; Carcinoma, Transitional Cell; Case-Control Studies; CD4-Positive T-Lymphocytes; Cell Count; Cell Hypoxia; Cell Line, Tumor; Cell Proliferation; Characiformes; Child; China; Cities; Cobalt; Colonic Neoplasms; Copper Sulfate; Cross-Sectional Studies; Cyclin-Dependent Kinase Inhibitor p16; Cytokines; Deoxycytidine; Diagnosis, Differential; Digestive System; Dihydroxyphenylalanine; Disease Models, Animal; DNA (Cytosine-5-)-Methyltransferase 1; DNA Barcoding, Taxonomic; DNA, Bacterial; Dose-Response Relationship, Drug; Down-Regulation; Edetic Acid; Electrochemical Techniques; Electrodes; Embolization, Therapeutic; Embryo, Nonmammalian; Environmental Monitoring; Enzyme-Linked Immunosorbent Assay; Epithelial-Mesenchymal Transition; Fatty Acids; Feces; Female; Follow-Up Studies; Food Contamination; Forkhead Box Protein M1; Fresh Water; Fungicides, Industrial; Gallium Isotopes; Gallium Radioisotopes; Gastrectomy; Gastric Bypass; Gastric Outlet Obstruction; Gastroplasty; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Genes, Bacterial; Genetic Markers; Genome, Bacterial; Genome, Mitochondrial; Glioma; Glycogen Synthase Kinase 3 beta; Goats; Gonads; Guatemala; Halomonadaceae; HEK293 Cells; Helicobacter Infections; Helicobacter pylori; Hepacivirus; Histone-Lysine N-Methyltransferase; Hormones; Humans; Hydroxybutyrate Dehydrogenase; Hypersplenism; Hypoxia-Inducible Factor 1, alpha Subunit; Immunohistochemistry; Iran; Japan; Lactuca; Laparoscopy; Larva; Ligands; Liver Neoplasms; Lymphocyte Activation; Macrophages; Malaria; Male; Mercury; Metabolic Syndrome; Metals, Heavy; Mice; Middle Aged; Milk, Human; Mitochondria; Models, Molecular; Molecular Structure; Mothers; Multilocus Sequence Typing; Muscles; Mutation; Nanocomposites; Nanotubes, Carbon; Neoplasm Invasiveness; Neoplasm Recurrence, Local; Neoplasms; Neoplastic Cells, Circulating; Neoplastic Stem Cells; Neuroimaging; Nitriles; Nitrogen Isotopes; Non-alcoholic Fatty Liver Disease; Nuclear Magnetic Resonance, Biomolecular; Obesity; Obesity, Morbid; Oligopeptides; Oxidation-Reduction; Pancreatic Neoplasms; Particle Size; Particulate Matter; Pepsinogen A; Pesticides; Pharmacogenetics; Phosphatidylinositol 3-Kinases; Phospholipids; Phylogeny; Plasmodium ovale; Plasmodium vivax; Platelet Count; Polyhydroxyalkanoates; Positron Emission Tomography Computed Tomography; Positron-Emission Tomography; Postoperative Complications; Pregnancy; Prevalence; Prognosis; Prospective Studies; Prostate-Specific Antigen; Prostatic Neoplasms; Protein Domains; Proto-Oncogene Proteins c-akt; Proton Magnetic Resonance Spectroscopy; Pseudogenes; PTEN Phosphohydrolase; Pyrazoles; Pyrimidines; Radiographic Image Interpretation, Computer-Assisted; Radiopharmaceuticals; Rats, Long-Evans; Rats, Sprague-Dawley; RAW 264.7 Cells; Reactive Oxygen Species; Real-Time Polymerase Chain Reaction; Receptor, Notch3; Receptors, G-Protein-Coupled; Receptors, Urokinase Plasminogen Activator; Recombinant Proteins; Repressor Proteins; Resveratrol; Retrospective Studies; Risk Assessment; Risk Factors; RNA, Messenger; RNA, Ribosomal, 16S; Salinity; Salvage Therapy; Seasons; Sequence Analysis, DNA; Seroepidemiologic Studies; Signal Transduction; Skin; Snails; Soluble Guanylyl Cyclase; Solutions; Spain; Species Specificity; Spheroids, Cellular; Splenic Artery; Stomach Neoplasms; Streptococcus pneumoniae; Structure-Activity Relationship; Sulfonamides; Sunlight; Surface Properties; Surgical Instruments; Surgical Wound Infection; Survival Rate; Tetrahydrouridine; Thinness; Thrombocytopenia; Tissue Distribution; Titanium; Tomography, X-Ray Computed; TOR Serine-Threonine Kinases; Tumor Microenvironment; Tumor Necrosis Factor-alpha; Turkey; Ubiquinone; Urologic Neoplasms; Viral Envelope Proteins; Wastewater; Water Pollutants, Chemical; Weather; Wnt Signaling Pathway; Xenograft Model Antitumor Assays; Young Adult

In conventional clinical use, cytosine arabinoside (ara-C) is rapidly deaminated by pyrimidine nucleoside deaminase to the nontoxic compound uracil arabinoside. Tetrahydrouridine (THU) effectively inhibits this enzymatic degradation but is by itself nontoxic. This study demonstrates that concomitant administration of THU markedly increases the myelosuppressive potency of ara-C. When 25 or 50 mg/kg of THU iv and 0.1--0.2 mg/kg of ara-C iv are given daily x 5 days, they produce moderate-to-severe leukopenia and mild-to-moderate thrombocytopenia. A dose of 25 mg/kg of THU with 0.1 mg/kg of ara-C iv daily x 5 days appears appropriate for phase II studies; it produces myelosuppression equivalent to that produced by 3 mg/kg/day x 5 days of ara-C alone. No toxicity occurred with this combination that would not have been expected from ara-C given alone in an equitoxic dose. Although THU and ara-C produced a reduction in peripheral blood and bone marrow blast cells in eight of nine patients with acute leukemia, bone marrow remission did not occur in any of these heavily pretreated patients.

Topics: Bone Marrow; Clinical Trials as Topic; Cytarabine; Drug Evaluation; Drug Synergism; Drug Therapy, Combination; Humans; Leukemia; Lymphoma; Middle Aged; Neoplasms; Nucleoside Deaminases; Pyrimidine Nucleosides; Tetrahydrouridine; Uridine

Oxidized methylcytidines 5-hydroxymethyl-2'deoxycytidine (5hmdC) and 5-formy-2'deoxycytidine (5fdC) are deaminated by cytidine deaminase (CDA) into genome-toxic variants of uridine, triggering DNA damage and cell death. These compounds are promising chemotherapeutic agents for cancer cells that are resistant to pyrimidine derivative drugs, such as decitabine and cytarabine, which are inactivated by CDA. In our study, we found that cancer cells infected with mycoplasma exhibited a markedly increased sensitivity to 5hmdC and 5fdC, which was independent of CDA expression of cancer cells. In vitro biochemical assay showed that the homologous CDA protein from mycoplasma was capable of deaminating 5hmdC and 5fdC into their uridine form. Moreover, mycoplasma infection increased the sensitivity of cancer cells to 5hmdC and 5fdC, whereas administration of Tetrahydrouridine (THU) attenuated this effect, suggesting that mycoplasma CDA confers a similar effect as human CDA. As mycoplasma infection occurs in many primary tumors, our findings suggest that intratumoral microbes could enhance the tumor-killing effect and expand the utility of oxidized methylcytidines in cancer treatment.

Topics: Cytidine Deaminase; Deoxycytidine; Humans; Mycoplasma Infections; Neoplasms; Tetrahydrouridine; Uridine

The study's goals were as follows: (1) to extend our past findings with rodent tumors to human tumors in nude mice, (2) to determine if the drug protocol could be simplified so that only CldC and one modulator, tetrahydrouridine (H4U), would be sufficient to obtain efficacy, (3) to determine the levels of deoxycytidine kinase and dCMP deaminase in human tumors, compared to adjacent normal tissue, and (4) to determine the effect of CldC on normal tissue radiation damage to the cervical spinal cord of nude mice.. The five human tumors used were as follows: prostate tumors, PC-3 and H-1579; glioblastoma, SF-295; breast tumor, GI-101; and lung tumor, H-165. The duration of treatment was 3-5 weeks, with drugs administered on Days 1-4 and radiation on Days 3-5 of each week. The biomodulators of CldC were N-(Phosphonacetyl)-L-aspartate (PALA), an inhibitor of aspartyl transcarbamoylase, 5-fluorodeoxycytidine (FdC), resulting in tumor-directed inhibition of thymidylate synthetase, and H4U, an inhibitor of cytidine deaminase. The total dose of focused irradiation of the tumors was usually 45 Gy in 12 fractions.. Marked radiosensitization was obtained with CldC and the three modulators. The average days in tumor regrowth delay for X-ray compared to drugs plus X-ray, respectively, were: PC-3 prostate, 42-97; H-1579 prostate, 29-115; glioblastoma, 5-51; breast, 50-80; lung, 32-123. Comparative studies with PC-3 and H-1579 using CldC coadministered with H4U, showed that both PALA and FdC are dispensable, and the protocol can be simplified with equal and possibly heightened efficacy. For example, PC-3 with X-ray and (1) no drugs, (2) CldC plus the three modulators, (3) a high dose of CldC, and (4) escalating doses of CldC resulted in 0/10, 3/9, 5/10, and 6/9 cures, respectively. The tumor regrowth delay data followed a similar pattern. After treating mice only 11/2 weeks with CldC + H4U, 92% of the PC-3 tumor cells were found to possess CldU in their DNA. The great majority of head-and-neck tumors from patient material had markedly higher levels of dC kinase and dCMP deaminase than found in adjacent normal tissue. Physiologic and histologic studies showed that CldC + H4U combined with X-ray, focused on the cervical spinal cord, did not result in damage to that tissue.. 5-CldC coadministered with only H4U is an effective radiosensitizer of human tumors. Ninety-two percent of PC-3 tumor cells have been shown to take up ClUra derived from CldC in their DNA after only 11/2 weeks and 2 weeks of bolus i.p. injections. Enzymatic alterations that make tumors successful have been exploited for a therapeutic advantage. The great electronegativity, coupled with the relatively small Van der Waal radius of the Cl atom, may result in CldC's possessing the dual advantageous properties of FdC on one hand and BrdU and IdU on the other hand. These advantages include autoenhancing the incorporation of CldUTP into DNA by not only overrunning but also inhibiting the formation of competing TTP pools in tumors. A clinical trial is about to begin, with head-and-neck tumors as a first target of CldC radiosensitization.

Topics: Animals; Breast Neoplasms; Carcinoma, Squamous Cell; Combined Modality Therapy; DCMP Deaminase; Deoxycytidine; Deoxycytidine Kinase; Female; Glioblastoma; Humans; Lung Neoplasms; Male; Mice; Mice, Nude; Neoplasm Proteins; Neoplasms; Prostatic Neoplasms; Radiation-Sensitizing Agents; Radiotherapy Dosage; Spinal Cord; Tetrahydrouridine

The present experiments were conducted to test the effects of the potent cytidine deaminase inhibitor tetrahydrouridine (THU) on the metabolism and cytotoxicity of 5-methyl-2'-deoxycytidine (5-Med-Cyd) in several human leukemia cell lines in vitro. It was observed that 5-Med-Cyd exerts its effects via deamination to thymidine, which is particularly toxic to human promyelocytic (HL-60) and T-cell (JM) leukemia cell lines in vitro. The deamination and the cytotoxicity of 5-Med-Cyd were effectively hindered by 10(-3) M THU in 3-day cultures of HL-60 cells. Although the catabolism of [14C]5-Med-Cyd in the HL-60 cell cultures was blocked by THU, no radioactive 5-Med-Cyd was incorporated into DNA. The cytotoxicity and DNA incorporation of fluorodeoxycytidine are enhanced by THU. Unlike that compound 5-Med-Cyd resembled more bromodeoxycytidine and iododeoxycytidine; THU decreases the toxicity of both of these deoxycytidine analogues.

Topics: Biotransformation; Cell Line; Cell Survival; Deoxycytidine; Humans; Kinetics; Neoplasms; Tetrahydrouridine; Uridine

Clinical studies of resistance to cytosine arabinoside have not produced agreement as to the specific biochemical lesions responsible for altered sensitivity, although experimental and clinical work supports the concept that a decreased ability to generate ara-CTP must be the ultimate effect of this lesion. 3-deazauridine, an inhibitor of CTP synthetase, was found to enhance ara-CTP production in murine tumor cells, and in the present study, was shown to inhibit deamination of ara-C at both the nucleoside and nucleotide level. Enhanced ara-CTP formation was observed in cells lacking cytidine deaminase (L1 210 and HL60), indicating that 3-deazauridine inhibition of deoxycytidylate deaminase may be important in this drug interaction.

Topics: 3-Deazauridine; Animals; Cytarabine; Cytidine Deaminase; Drug Interactions; Drug Resistance; Humans; Mice; Neoplasms; Tetrahydrouridine

[14C]-tetrahydrouridine (THU), a strong inhibitor of cytidine (CR) deaminase, was, after iv administration, rapidly and quantitatively cleared from the blood with a plasma half-life of about 1 hour. The main pathway of excretion was through the kidneys: most of a dose of 50 mg/kg was excreted within 12 hours and excretion was essentially complete within 48 hours. Oral administration of the same dose revealed absorption of about 10% from the gastrointestinal tract. THU at 10, 25, and 50 mg/kg given 15 minutes before [3H]-cytosine arabinoside (ara-C) at a dose of 0.003 mg/kg produced about a two fold increase in ara-C blood levels at all times measured from 5 minutes to 4 hours, with only slight increases in the half-life of ara-C. A dose-related effect of THU upon the deamination of ara-C was obvious only during the time from 15 minutes to 1 hour after the injection of 3H-ara-C. The inhibitory effect of THU upon CR deaminase was also reflected in a considerably increased ratio of ara-C/uracil arabinoside in the urine.

Topics: Administration, Oral; Biological Availability; Cytarabine; Cytidine Deaminase; Deamination; Dose-Response Relationship, Drug; Drug Therapy, Combination; Half-Life; Humans; Injections, Intravenous; Neoplasms; Tetrahydrouridine; Uridine