Related Experiment Video
Updated: Jun 15, 2026

Testing Targeted Therapies in Cancer using Structural DNA Alteration Analysis and Patient-Derived Xenografts
Published on: July 25, 2020
Pharmacokinetics of methotrexate in solid tumors
1Department of Chemical Engineering, University of Delaware, Newark, Delaware 19711, USA.
Methotrexate (MTX) transport into tumors differs based on tumor type and drug dosage. Mathematical modeling revealed flow-limited uptake in hepatoma 5123 and tissue-limited uptake in Walker 256 carcinoma.
Area of Science:
- Pharmacokinetics and drug delivery
- Cancer biology and tumor microenvironment
- Mathematical modeling in medicine
Background:
- Understanding drug transport into solid tumors is crucial for optimizing chemotherapy efficacy.
- Methotrexate (MTX) is a widely used chemotherapeutic agent, but its delivery to tumors can be a limiting factor.
- Differential drug uptake mechanisms can influence treatment response.
Purpose of the Study:
- To investigate the transport kinetics of methotrexate (MTX) into two distinct solid tumors: Walker 256 carcinoma (W256) and hepatoma 5123 (H5123) in rats.
- To develop and validate a mathematical model describing MTX distribution and transport within these tumors.
- To compare MTX uptake efficiency and transport limitations between different tumor types and dosages.
Main Methods:
- Administering MTX via pulse injection and continuous infusion to tumor-bearing rats.
- Developing a mathematical model to simulate MTX distribution and transport dynamics.
- Utilizing micropore chambers to sample tumor interstitial fluid and measure MTX concentration over time.
- Analyzing MTX concentration in relation to plasma levels and tumor characteristics.
Main Results:
- A mathematical model accurately described MTX transport in both W256 and H5123 tumors.
- Hepatoma 5123 exhibited flow-limited MTX transport, dependent on plasma drug levels.
- Walker 256 carcinoma demonstrated tissue-limited MTX transport, influenced by diffusion across barriers.
- Tumor uptake efficiency was significantly higher (nearly eightfold) with lower MTX doses compared to higher doses.
- MTX concentration in tumor interstitial fluid reached equilibrium with plasma in approximately 50 hours.
- Higher MTX concentrations were observed in resistant tumors compared to responsive tumors.
Conclusions:
- MTX transport mechanisms vary significantly between different solid tumor types.
- Tumor type dictates whether drug delivery is limited by blood flow or tissue diffusion.
- Lower MTX doses appear more efficient for tumor uptake than higher doses.
- Drug resistance in tumors correlates with higher intracellular MTX concentrations, suggesting complex pharmacodynamic interactions.
More Related Videos
08:04Cytotoxic Efficacy of Photodynamic Therapy in Osteosarcoma Cells In Vitro
Published on: March 18, 2014
08:57Sample Extraction and Simultaneous Chromatographic Quantitation of Doxorubicin and Mitomycin C Following Drug Combination Delivery in Nanoparticles to Tumor-bearing Mice
Published on: October 5, 2017
Related Concept Videos
Effect of Hepatic Disease on Pharmacokinetics: Active Drug, Metabolite and Fraction of Metabolized Drug
Pharmacokinetics in Pediatric Patients: Drug Metabolism
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase
Pharmacokinetics in Pediatric Patients: Drug Excretion
Therapeutic Drug Monitoring: Affecting Factors
Pharmacokinetic–Pharmacodynamic Relationship: Duration of Dose-Effect Relationship