Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Radiol. Sep 28, 2016; 8(9): 799-808
Published online Sep 28, 2016. doi: 10.4329/wjr.v8.i9.799
Evaluation of DNA synthesis with carbon-11-labeled 4′-thiothymidine
Jun Toyohara
Jun Toyohara, Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, Tokyo 173-0015, Japan
Author contributions: Toyohara J generated the figures and wrote the manuscript.
Supported by A Grant-in-Aid for Scientific Research from the Japan Society for the Promotion of Science, No. (B) 25293271.
Conflict-of-interest statement: The author declares that he has no competing interests.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Correspondence to: Jun Toyohara, PhD, Theme Leader, Research Team for Neuroimaging, Tokyo Metropolitan Institute of Gerontology, 35-2 Sakae-cho, Itabashi-ku, Tokyo 173-0015, Japan.
Telephone: +81-3-39643210 Fax: +81-3-39641148
Received: February 25, 2016
Peer-review started: February 27, 2016
First decision: May 13, 2016
Revised: June 12, 2016
Accepted: July 29, 2016
Article in press: August 1, 2016
Published online: September 28, 2016

In the cancer research field, the preferred method for evaluating the proliferative activity of cancer cells in vivo is to measure DNA synthesis rates. The cellular proliferation rate is one of the most important cancer characteristics, and represents the gold standard of pathological diagnosis. Positron emission tomography (PET) has been used to evaluate in vivo DNA synthetic activity through visualization of enhanced nucleoside metabolism. However, methods for the quantitative measurement of DNA synthesis rates have not been fully clarified. Several groups have been engaged in research on 4′-[methyl-11C]-thiothymidine (11C-4DST) in an effort to develop a PET tracer that allows quantitative measurement of in vivo DNA synthesis rates. This mini-review summarizes the results of recent studies of the in vivo measurement of cancer DNA synthesis rates using 11C-4DST.

Keywords: 4′-[methyl-11C]-thiothymidine, DNA synthesis, Cell proliferation, Tumor, Positron emission tomography

Core tip: There is a continuous demand to measure in situ DNA synthesis rates in living human cancer. The thymidine derivative 4′-[methyl-11C] thiothymidine (11C-4DST) has the potential to visualize in vivo DNA synthesis rates with positron emission tomography (PET). To confirm whether 11C-4DST is a valid DNA synthesis marker, clinical and basic research is being conducted at several PET centers in Japan, European Union, and the United States. This mini-review summarizes the progress of recent studies involving the in vivo imaging of cancer DNA synthesis using 11C-4DST PET.