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Forshaw, T. E.

Publications and source records attributed to Forshaw, T. E..

2 recordsLinked to original sources

DCP, First Generation PET Radiotracer for Diagnosis of Radiation Resistant Head and Neck Cancer

Redox metabolism plays essential functions in the pathology of cancer. As tumor redox profiles uniquely reflect cancer stage and in select cases, therapeutic sensitivity, the capability to image redox molecular features is essential to improve diagnosis, treatment, and overall quality-of-life (QOL) of cancer patients. While a number of radiotracers for imaging redox metabolism have been developed, there are no reports of radiotracers for in vivo imaging of protein oxidation. Here we take the first step towards this goal and describe the synthesis and kinetic properties of a new positron emission tomography (PET) [18F]DCP radiotracer for in vivo imaging of protein sulfenylation. Time course biodistribution and PET/CT studies using xenograft animal models of Head and Neck Squamous Cell Cancer (HNSCC) demonstrate feasibility of diagnosing radiation resistant tumors, which display lower [18F]DCP signal. These findings are consistent with our previous reports of decreased protein sulfenylation in clinical specimens of radiation resistant HNSCC. We anticipate further development and implementation of this concept in clinical practice to improve the diagnosis of patients with radiation resistant tumors and the accuracy of prognosis for patients undergoing radiation treatment. Single Sentence SummaryThe study introduces a new PET radiotracer for profiling tumor protein oxidation as a prognostic indicator of resistance to radiation therapy.

cancer biology

Personalized Genome-Scale Metabolic Models Identify Targets of Redox Metabolism in Radiation-Resistant Tumors

Redox cofactor production is integral towards antioxidant generation, clearance of reactive oxygen species, and overall tumor response to ionizing radiation treatment. To identify systems-level alterations in redox metabolism which confer resistance to radiation therapy, we developed a bioinformatics pipeline for integrating multi-omics data into personalized genome-scale flux balance analysis models of 716 radiation-sensitive and 199 radiation-resistant tumors. These models collectively predicted that radiation-resistant tumors reroute metabolic flux to increase mitochondrial NADPH stores and ROS scavenging. Simulated genome-wide knockout screens agreed with experimental siRNA gene knockdowns in matched radiation-sensitive and -resistant cancer cell lines, revealing gene targets involved in mitochondrial NADPH production, central carbon metabolism, and folate metabolism that allow for selective inhibition of glutathione production and H2O2 clearance in radiation-resistant cancers. This systems approach represents a significant advancement in developing quantitative genome-scale models of redox metabolism and identifying personalized metabolic targets for improving radiation sensitivity in individual cancer patients.

systems biology