Novartis

About: Novartis is a company organization based out in Basel, Switzerland. It is known for research contribution in the topics: Alkyl & Population. The organization has 41930 authors who have published 50566 publications receiving 1978996 citations. The organization is also known as: Novartis International AG.

Dnmt3a-Dependent Nonpromoter DNA Methylation Facilitates Transcription of Neurogenic Genes

Abstract: DNA methylation at proximal promoters facilitates lineage restriction by silencing cell type-specific genes. However, euchromatic DNA methylation frequently occurs in regions outside promoters. The functions of such nonproximal promoter DNA methylation are unclear. Here we show that the de novo DNA methyltransferase Dnmt3a is expressed in postnatal neural stem cells (NSCs) and is required for neurogenesis. Genome-wide analysis of postnatal NSCs indicates that Dnmt3a occupies and methylates intergenic regions and gene bodies flanking proximal promoters of a large cohort of transcriptionally permissive genes, many of which encode regulators of neurogenesis. Surprisingly, Dnmt3a-dependent nonproximal promoter methylation promotes expression of these neurogenic genes by functionally antagonizing Polycomb repression. Thus, nonpromoter DNA methylation by Dnmt3a may be used for maintaining active chromatin states of genes critical for development.

Clinical Pharmacokinetics of Imatinib

Abstract: Imatinib is a potent and selective inhibitor of the protein tyrosine kinase Bcr-Abl, platelet-derived growth factor receptors (PDGFRα and PDGFRβ) and KIT. Imatinib is approved for the treatment of chronic myeloid leukaemia (CML) and gastrointestinal stromal tumour (GIST), which have dysregulated activity of an imatinib-sensitive kinase as the underlying pathogenetic feature. Pharmacokinetic studies of imatinib in healthy volunteers and patients with CML, GIST and other cancers show that orally administered imatinib is well absorbed, and has an absolute bioavailability of 98% irrespective of oral dosage form (solution, capsule, tablet) or dosage strength (100mg, 400mg). Food has no relevant impact on the rate or extent of bioavailability. The terminal elimination half-life is approximately 18 hours. Imatinib plasma concentrations predictably increase by 2- to 3-fold when reaching steady state with 400mg once-daily administration, to 2.6 ± 0.8 μg/mL at peak and 1.2 ± 0.8 μg/mL at trough, exceeding the 0.5 μg/mL (1 μmol/L) concentrations needed for tyrosine kinase inhibition in vitro and leading to normalisation of haematological parameters in the large majority of patients with CML irrespective of baseline white blood cell count. Imatinib is approximately 95% bound to human plasma proteins, mainly albumin and α1-acid glycoprotein. The drug is eliminated predominantly via the bile in the form of metabolites, one of which (CGP 74588) shows comparable pharmacological activity to the parent drug. The faecal to urinary excretion ratio is approximately 5:1. Imatinib is metabolised mainly by the cytochrome P450 (CYP) 3A4 or CYP3A5 and can competitively inhibit the metabolism of drugs that are CYP3A4 or CYP3A5 substrates. Interactions may occur between imatinib and inhibitors or inducers of these enzymes, leading to changes in the plasma concentration of imatinib as well as coadministered drugs. Hepatic and renal dysfunction, and the presence of liver metastases, may result in more variable and increased exposure to the drug, although typically not necessitating dosage adjustment. Age (range 18–70 years), race, sex and bodyweight do not appreciably impact the pharmacokinetics of imatinib.

Dinucleoside phosphinates and their pharmaceutical compositions

Abstract: A dinucleotide analogue of formula ##STR1## where B1 and B2 are each independently a monovalent nucleoside base radical; R1 is R1 a or Z; R1 a, R2, R3 and R4 are each independently hydrogen, halogen or hydroxy; R5 is R5 a or Z; R6 is hydrogen or R6 a ; R7 is hydrogen, alkyl-N,N-dialkylphosphoramidyl or R7 a, R8 is R8 a or Z, or the indicated R7 O and R8 together denote an isopropylidenedioxy group; R5 a and R8 a are each independently hydrogen, halogen, hydroxy, --OR10, --OCOR10 or silyloxy substituted by three C1 -C15 hydrocarbyl groups; R6 a and R7 a are each independently a C1 -C10 aliphatic radical, a C6 -C15 aromatic radical, a C7 -C30 araliphatic radical, --COR11, --SO2 R11 or silyl substituted by three C1 -C15 hydrocarbyl groups; R9 is hydrogen, a C1 -C8 aliphatic radical, a C3 -C8 cycloaliphatic radical, a C6 -C15 aromatic radical, a C7 -C13 araliphatic radical, an alkali metal ion or an ammonium ion; R10 and R11 are each independently a C1 -C10 aliphatic radical, a C3 -C8 cycloaliphatic radical, a C6 -C15 aromatic radical or a C7 -C16 araliphatic radical; Rx and Ry are independently hydrogen, halogen, hydroxy, a C1 -C10 alkyl, C2 -C10 alkenyl, C3 -C8 cycloalkyl, C6 -C15 aryl, C7 -C16 aralkyl, C1 -C10 alkoxy, C2 -C10 alkenoxy, C6 -C10 aryloxy or C7 -C16 aralkyloxy group, which is substituted or unsubstituted, or --OCORz ; Rz is a substituted or unsubstituted C1 -C10 alkyl, C2 -C10 alkenyl, C3 -C8 cycloalkyl, C6 -C15 aryl or C7 -C16 aralkyl group; and Z is C6 -C10 aryloxythiocarbonyloxy, the C6 -C10 aryl group being substituted or unsubstituted.

A comprehensive survey of genomic alterations in gastric cancer reveals systematic patterns of molecular exclusivity and co-occurrence among distinct therapeutic targets

Abstract: Objective Gastric cancer is a major gastrointestinal malignancy for which targeted therapies are emerging as treatment options. This study sought to identify the most prevalent molecular targets in gastric cancer and to elucidate systematic patterns of exclusivity and co-occurrence among these targets, through comprehensive genomic analysis of a large panel of gastric cancers. Design Using high-resolution single nucleotide polymorphism arrays, copy number alterations were profiled in a panel of 233 gastric cancers (193 primary tumours, 40 cell lines) and 98 primary matched gastric non-malignant samples. For selected alterations, their impact on gene expression and clinical outcome were evaluated. Results 22 recurrent focal alterations (13 amplifications and nine deletions) were identified. These included both known targets ( FGFR2 , ERBB2 ) and also novel genes in gastric cancer ( KLF5 , GATA6 ). Receptor tyrosine kinase (RTK)/RAS alterations were found to be frequent in gastric cancer. This study also demonstrates, for the first time, that these alterations occur in a mutually exclusive fashion, with KRAS gene amplifications highlighting a clinically relevant but previously underappreciated gastric cancer subgroup. FGFR2 -amplified gastric cancers were also shown to be sensitive to dovitinib, an orally bioavailable FGFR/VEGFR targeting agent, potentially representing a subtype-specific therapy for FGFR2 -amplified gastric cancers. Conclusion The study demonstrates the existence of five distinct gastric cancer patient subgroups, defined by the signature genomic alterations FGFR2 (9% of tumours), KRAS (9%), EGFR (8%), ERBB2 (7%) and MET (4%). Collectively, these subgroups suggest that at least 37% of gastric cancer patients may be potentially treatable by RTK/RAS directed therapies.