Generation and characterization of novel cytochrome P450 Cyp2c gene cluster knockout and CYP2C9 humanized mouse lines.

Compared with rodents and many other animal species, the human cytochrome P450 (P450) Cyp2c gene cluster varies significantly in the multiplicity of functional genes and in the substrate specificity of its enzymes. As a consequence, the use of wild-type animal models to predict the role of human CYP2C enzymes in drug metabolism and drug-drug interactions is limited. Within the human CYP2C cluster CYP2C9 is of particular importance, because it is one of the most abundant P450 enzymes in human liver, and it is involved in the metabolism of a wide variety of important drugs and environmental chemicals.

Generation and characterization of a novel multidrug resistance protein 2 humanized mouse line.

The multidrug resistance protein (MRP) 2 is predominantly expressed in liver, intestine, and kidney, where it plays an important role in the excretion of a range of drugs and their metabolites or endogenous compounds into bile, feces, and urine. Mrp knockout [Mrp2(-/-)] mice have been used recently to study the role of MRP2 in drug disposition. Here, we describe the first generation and initial characterization of a mouse line humanized for MRP2 (huMRP2), which is nulled for the mouse Mrp2 gene and expresses the human transporter in the organs and cell types where MRP2 is normally expressed.

HIF-1alpha mRNA is not associated with histopathological regression following neoadjuvant chemoradiation in esophageal cancer.

Background: Hypoxia-inducible factor-1alpha (HIF-1alpha) expression was reported to be associated with tumor growth, progression and resistance to radio-/chemotherapy. Whether HIF-1alpha mRNA or protein expression is associated with histomorphological response or prognosis following neoadjuvant chemoradiation and surgery in resectable, locally-advanced esophageal cancer was analyzed.

Patients And Methods: Fifty-three patients received neoadjuvant chemoradiation (cisplatin, 5-fluorouracil, 36 Gy) followed by transthoracic en bloc esophagectomy.