Serum induces a transcriptional activation of CYP1A1 gene in HepG2 independently of the AhR pathway.

CYP1A1 is largely implicated in carcinogenesis. To date, it is known that this gene is induced by xenobiotics such as polycyclic aromatic hydrocarbons. In this study, we evaluated the effect of serum in the regulation of CYP1A1 gene expression.

Involvement of nuclear factor kappaB in c-Myc induction by tubulin polymerization inhibitors.

We showed previously that microtubule disassembly by vinblastine induces the proto-oncogene c-myc in epithelial mammary HBL100 cells. In this study, we demonstrate that vinblastine treatment in these cells, in contrast to what was observed with the colon adenocarcinoma cell line HT29-D4, activated the transcription factor NFkappaB, which has been involved in c-myc regulation. The microtubule disassembly also induced IkappaB degradation.

Metabolism of carbamazepine by CYP3A6: a model for in vitro drug interactions studies.

Carbamazepine (CBZ) is widely used in the treatment of epilepsy. The drug is principally metabolized by CYPs to 10, 11-epoxy carbamazepine (CBZ-E) but this metabolite more toxic than the parent drug, does possess anticonvulsant properties. In humans, CYP3A4, CYP2C8 and CYP1A2 have been shown to be implicated in CBZ biotransformation.

Evidence for the existence of two human CYP2E1 cDNAs using different polyadenylation signals.

We have isolated a cDNA (named P450 A) which is a variant of CYP2E1 presenting some differences in the 3' non coding region. Two substitutions and only one polyadenylation signal were detected on P450 A compared to CYP2E1 where there are two. With the aim of studying the frequency of utilization of these polyadenylation signals, probe A and probe J specific for P450 A and CYP2E1, respectively, were hybridized on human hepatic and extra-hepatic cDNA samples.