FDG kinetics in cells and tissues: a biochemically-driven compartmental approach

TL;DR

This paper introduces a new compartmental model for FDG tracer kinetics that differentiates between cytosol and endoplasmic reticulum, aligning better with biochemical evidence and improving data interpretation in cancer studies.

Contribution

The paper presents a biochemically-driven compartmental model that emphasizes cellular organelles, providing more accurate analysis of FDG kinetics in cells and tissues.

Findings

Tracer accumulates mainly in the endoplasmic reticulum.

Phosphorylation rate is higher than current models suggest.

Model shows better agreement with biochemical experiments.

Abstract

The radioactive glucose analogue 2-deoxy-2-[18F]fluoro-D-glucose (FDG) is widely used to reconstruct glucose metabolism and other biological functions in cells and tissues. The analysis of data on the time course of FDG tracer distribution is performed by the use of appropriate compartmental models. Motivated by recent results in cell biochemistry, we describe a new compartmental model aiming at the reconstruction of tracer kinetics in cells and tissues, which emphasizes the different roles of the cytosol and of the endoplasmic reticulum. Two applications of the new model are examined, that are concerned with real data from cancer cell cultures in vitro, and cancer tissues in vivo. The results are compared with those obtained through application of more standard compartmental models against the same datasets and appear to be in a better agreement with respect to recent biochemical experimental evidence. In particular, it is shown that tracer tends to accumulate in the endoplasmic reticulum, rather than cytosol, and that the rate of phosphorylation is higher than predicted by current models.