ABSTRACT
PURPOSE: The purpose of this study was to evaluate the effect of bevacizumab on the pharmacokinetics (PK) of irinotecan and its active metabolite. Exploratory analyses of the impact of variability in uridine diphosphate glucuronosyltransferase 1A (UGT1A) genes on irinotecan metabolism and toxicity were conducted. METHODS: This was an open-labeled, fixed-sequence study of bevacizumab with FOLFIRI (irinotecan, leucovorin, and infusional 5-fluorouracil). Pharmacokinetic assessments were conducted in cycles 1 and 3. RESULTS: Forty-five subjects were enrolled. No difference in dose-normalized AUC(0-last) for irinotecan and SN-38 between irinotecan administered alone or in combination with bevacizumab was identified. Leukopenia was associated with higher exposure to both irinotecan and SN-38. UGT1A1 polymorphisms were associated with variability in irinotecan PK. Gastrointestinal toxicity was associated with UGT1A6 genotype. No other associations between UGT1A genotypes and toxicity were detected. CONCLUSION: Bevacizumab does not affect irinotecan PK when administered concurrently. A variety of pharmacogenetic relationships may influence the pharmacokinetics of irinotecan and its toxicity.
Subject(s)
Antibodies, Monoclonal/pharmacology , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Camptothecin/analogs & derivatives , Glucuronosyltransferase/genetics , Neoplasms/drug therapy , Adult , Aged , Antibodies, Monoclonal, Humanized , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Area Under Curve , Bevacizumab , Camptothecin/administration & dosage , Camptothecin/adverse effects , Camptothecin/pharmacokinetics , Drug Interactions , Female , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Gastrointestinal Tract/drug effects , Gastrointestinal Tract/pathology , Genotype , Humans , Irinotecan , Leucovorin/administration & dosage , Leucovorin/adverse effects , Leukopenia/chemically induced , Male , Middle Aged , Pharmacogenetics , Polymorphism, Genetic , ProdrugsABSTRACT
Expression and tracking of fluorescent fusion proteins has revolutionized our understanding of basic concepts in cell biology. The protocol presented here has underpinned much of the in vivo results highlighting the dynamic nature of the plant secretory pathway. Transient transformation of tobacco leaf epidermal cells is a relatively fast technique to assess expression of genes of interest. These cells can be used to generate stable plant lines using a more time-consuming, cell culture technique. Transient expression takes from 2 to 4 days whereas stable lines are generated after approximately 2 to 4 months.
Subject(s)
Gene Transfer Techniques , Green Fluorescent Proteins/metabolism , Nicotiana/metabolism , Recombinant Fusion Proteins/metabolism , Cloning, Molecular/methods , Gene Expression , Rhizobium/genetics , Tissue Culture Techniques , Nicotiana/geneticsABSTRACT
Tobacco Bright Yellow-2 (BY-2) suspension cells are a widely used biological material for studying plant cell morphology and physiology. These cells are easy to transform and maintain in culture and tolerate transformation with fluorescent proteins such as the green fluorescent protein and its derivatives. These, by the addition of plant or mammalian targeting sequences, can be directed to specific subcellular locations for the study of cell dynamics in vivo. This unit describes the production of BY-2 cell stable transformants via an Agrobacterium based method to permit the visualisation of cellular components in vivo by epifluorescence or confocal microscopy.
