Induction of UGT1A1 and CYP2B6 by an antimitogenic factor in HepG2 cells is mediated through suppression of cyclin-dependent kinase 2 activity: Cell-cycle dependent expression

Autor: Junko Sugatani, Masatoshi Kurosawa, Naomi Kitamura, Masao Miwa, Makoto Osabe, Akira Ikari
Jazyk: angličtina
Rok vydání: 2010
Předmět:
Small interfering RNA
Receptors
Steroid

Pharmaceutical Science
Gene Expression
Receptors
Cytoplasmic and Nuclear

Histones
Phosphatidylinositol 3-Kinases
Cytochrome P-450 CYP3A
Glucuronosyltransferase
Phosphorylation
RNA
Small Interfering

Extracellular Signal-Regulated MAP Kinases
Cyclin-Dependent Kinase Inhibitor Proteins
Phosphoinositide-3 Kinase Inhibitors
biology
Hepatocyte Growth Factor
Cell Cycle
Pregnane X Receptor
Transfection
Hep G2 Cells
Cyclin-Dependent Kinases
Gene Expression Regulation
Neoplastic

Enzyme Induction
Intercellular Signaling Peptides and Proteins
Hepatocyte growth factor
Aryl Hydrocarbon Hydroxylases
Signal transduction
medicine.drug
Signal Transduction
digestive system
Cyclin-dependent kinase
Cell Line
Tumor

medicine
Cytochrome P-450 CYP1A1
Roscovitine
Humans
Protein Kinase Inhibitors
Cell Proliferation
Pharmacology
Cyclin-dependent kinase 2
Cyclin-Dependent Kinase 2
JNK Mitogen-Activated Protein Kinases
Oxidoreductases
N-Demethylating

Molecular biology
digestive system diseases
Cytochrome P-450 CYP2B6
Cell culture
Purines
biology.protein
CDK inhibitor
Zdroj: Drug Metab. Dispos.. 38:177-186
Popis: Hepatocyte growth factor (HGF), an antimitogenic factor for HepG2 cells, increased mRNA and protein levels of UGT1A1 and CYP2B6, as well as the endogenous cyclin-dependent kinase (CDK) inhibitors p16, p21, and p27 in HepG2 cells but not in HuH6, Caco2, or MCF7 cells. Treatment with 1,4-diamino-2,3-dicyano-1,4-bis(methylthio)butadiene (U0126) (an extracellular signal-regulated kinase inhibitor) suppressed the HGF-induced expression of UGT1A1 and CYP2B6, as well as p16, p21, and p27 in HepG2 cells. The CDK inhibitor roscovitine also enhanced the expression of UGT1A1, CYP2B6, and CYP3A4. Transfection of anti-CDK2 siRNA led to elevated levels of UGT1A1, CYP2B6, and CYP3A4 in HepG2 and SW480 cells, whereas anti-CDK4 small interfering RNA (siRNA) did not significantly enhance the expression of these enzymes. In fact, CDK2 activity was decreased in HGF-treated HepG2 cells. In cells arrested in S phase by a thymidine block and then released into a synchronous cell cycle, there was a clear dissociation among the activation of CDK2 and the expression of UGT1A1, CYP2B6, and CYP3A4. Furthermore, the induction of CYP3A4 but not UGT1A1 or CYP2B6 mRNA expression by roscovitine was repressed in pregnane X receptor (PXR) siRNA-transfected HepG2 cells. Transfection with constitutive androstane receptor siRNA or PXR siRNA in HepG2 cells did not repress the HGF-stimulated expression of UGT1A1 mRNA. Taken together, our results show that the expression of UGT1A1 and CYP2B6 is negatively regulated through a CDK2 signaling pathway linked to cell cycle progression in HepG2 and SW480 cells, the mechanism of which may differ from that of CYP3A4 expression through PXR phosphorylated by CDK2.
Databáze: OpenAIRE