Related Experiment Video
Updated: Feb 3, 2026

Preparation and Evaluation of 99mTc-labeled Tridentate Chelates for Pre-targeting Using Bioorthogonal Chemistry
Published on: February 4, 2017
SPECT Imaging of Treatment-Related Tumor Necrosis Using Technetium-99m-Labeled Rhein
Jiajia Liang1,2,3, Qi Luo1,2,3, Dongjian Zhang1,3
1Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, 210028, Jiangsu Province, People's Republic of China.
Purpose:
Noninvasive imaging of treatment-induced necrosis is important to distinguish early responders from patients resistant to the treatment plan, enabling the tailored-made therapeutic intervention. The purpose of this study was to explore the feasibility of [99mTc]EDDA-HYNIC-2C-rhein for early assessment of tumor response to treatment.
Procedures:
In vitro necrosis avidity of [99mTc]EDDA-HYNIC-2C-rhein was evaluated in human lung cancer A549 cells treated with hyperthermia. Single photon emission-computed tomography/X-ray-computed tomography (SPECT/CT) imaging was performed in rats bearing subcutaneous W256 tumor treated with combretastatin A-4 disodium phosphate (CA4P) and rats bearing orthotopic liver W256 tumor treated with a single microwave ablation. All rats were euthanized immediately after the imaging session for biodistribution and histology studies. The mechanism of necrosis avidity for the tracer was further explored by in vivo blocking experiment and in vitro histochemistry and fluorescence staining.
Results:
The uptake of [99mTc]EDDA-HYNIC-2C-rhein in necrotic cells was significantly higher than that in viable cells (p < 0.05). SPECT/CT imaging showed that an obvious "hot spot" was observed in the CA4P-treated tumor while not in the control tumor at 5 h after tracer injection. Ex vivo γ-counting revealed that the uptake of [99mTc]EDDA-HYNIC-2C-rhein in tumor was increased 3.5-fold in rats treated with CA4P compared with rats treated with vehicle. Autoradiography and corresponding H&E staining suggested that the higher overall radiotracer uptake in the treated tumors was attributed to the increased necrosis. Blocking with unlabeled HYNIC-2C-rhein demonstrated the specific binding of the radiotracer to necrotic tissues. The perfect match of autoradiograph and histochemistry staining and PI fluorescence staining revealed that necrosis avidity of the tracer may be attributable to intercalation with exposed DNA in necrotic tissues.
Conclusion:
[99mTc]EDDA-HYNIC-2C-rhein can image necrosis induced by anticancer therapy and holds potential for early assessment of treatment response.
More Related Videos
Related Concept Videos
Necrosis
Morphological Manifestations of Necrosis
Necrotic cells show different types of morphological appearance depending on the type of tissue and infection. In coagulative necrosis, cells become...
Labeling Emotion
Labeling DNA Probes
Radioisotopes, fluorophores, or small molecule binding partners like biotin or digoxigenin, are the most widely used reporter tags for labeling DNA probes. These labels can be attached to the probe DNA molecule via...
Open Angle Glaucoma: Treatment
Drugs such as carbonic anhydrase inhibitors, α2- and...
Treatment Resistant Cancers
Parkinson's Disease: Treatment
Parkinson's Disease is primarily a result of the loss of dopaminergic neurons in the substantia nigra pars compacta. The cornerstone of...

