The uptake of 3?-deoxy-3?-[18F]fluorothymidine into L5178Y tumours in vivo is dependent on thymidine kinase 1 protein levels

Abstract

This study shows that in vivo [18F]FLT kinetics depend on TK1 protein expression. ATP may be important in realising this effect. Thus, [18F]FLT-PET has the potential to yield specific information on tumour proliferation in diagnostic imaging and therapy monitoring.

Initial evaluation of 18F-fluorothymidine (FLT) PET/CT scanning for primary pancreatic cancer

“…FLT transport and uptake is not entirely dependent on the activity of thymidine kinase 1 (TK1) alone, but ATP may also act as an important cofactor [11,12]. The primary cancers in this study were all of moderate size or greater, and there may have been a paucity of available ATP leading to suboptimal modulation of TK1.…”

In Vivo Characterization of Proliferation for Discriminating Cancer from Pancreatic Pseudotumors

“…Barthel et al reported that in vivo uptake of 18 F-FLT is closely related to thymidine kinase 1 activity and the cellular concentration of adenosine triphosphate (32). However, FIGURE 4.…”

First Demonstration of Leukemia Imaging with the Proliferation Marker 18F-Fluorodeoxythymidine

“…18 F-FLT acts as a chain terminator and is only marginally incorporated into DNA and therefore not a direct measure of proliferation (22). In vitro studies indicate that 18 F-FLT uptake is closely related to thymidine kinase 1 activity and respective protein levels (35), as well as to expression of nucleoside transporters in the cellular membrane (36). 18 F-FLT is considered to reflect thymidine kinase 1 activity and, hence, S-phase fraction rather than DNA synthesis.…”