Mathematical modeling of herpes simplex virus distribution in solid tumors: implications for cancer gene therapy

Area of Science:

• Oncolytic virotherapy
• Mathematical modeling of viral kinetics
• Cancer treatment strategies

Background:

• Oncolytic viral vectors offer a promising approach for cancer treatment.
• Limited tumor distribution and propagation of viruses often hinder therapeutic efficacy.
• Understanding viral spread dynamics is crucial for optimizing oncolytic virotherapy.

Purpose of the Study:

• To develop a mathematical model describing the spread of herpes simplex virus (HSV) within a tumor.
• To identify factors limiting viral distribution and propagation from the injection site.
• To explore strategies for enhancing the efficacy of oncolytic HSV therapy.

Main Methods:

• A mathematical model simulating viral spread in a spherical tumor.
• Incorporation of parameters: reversible binding, interstitial diffusion, viral degradation, and internalization.
• Consideration of three viral species: free interstitial, cell-surface bound, and internalized virus.

Main Results:

• Rapid viral binding, internalization, and hindered diffusion restrict virus spread to the injection site.
• Increasing viral dose to overcome these limitations is unsafe due to potential toxicity.
• Decreasing viral binding affinity or increasing diffusion coefficient can enhance infected cell numbers by over 1.5-fold.

Conclusions:

• The study provides criteria for assessing tumor response to oncolytic HSV therapy.
• Modifications to vector delivery, viral properties, and tumor microenvironment can improve therapeutic outcomes.
• Mathematical modeling is a valuable tool for optimizing oncolytic virus design and application.