Characterization of [(99m)Tc]Duramycin as a SPECT Imaging Agent for Early Assessment of Tumor Apoptosis.

ABSTRACT:

Purpose

We investigated the usefulness of [(99m)Tc]duramycin for monitoring early response to cancer therapy in mice, with an eye towards clinical translation.

Procedures

[(99m)Tc]Duramycin was injected in healthy CD1-/- mice to estimate human [(99m)Tc]duramycin radiation dose. [(99m)Tc]Duramycin single-photon emission computed tomography (SPECT) imaging of apoptosis was evaluated in a mouse model of colorectal cancer treated with irinotecan and validated ex vivo using autoradiography, cleaved caspase-3, and TdT-mediated dUTP nick-end labeling (TUNEL) histology of the tumors.

Results

The mean effective dose was estimated to be 3.74?×?10(-3)?±?3.43?×?10(-4) mSv/MBq for non-purified and 3.19?×?10(-3)?±?2.16?×?10(-4) mSv/MBq for purified [(99m)Tc]duramycin. [(99m)Tc]Duramycin uptake in vivo following therapy increased significantly in apoptotic irinotecan-treated tumors (p?=?0.008). Radioactivity in the tumors positively correlated with cleaved caspase-3 (r?=?0.85, p?Conclusion[(99m)Tc]Duramycin can be used to detect early chemotherapy-induced tumor cell death, and thus, may be a prospective candidate for clinical SPECT imaging of tumor response to therapy.

SUBMITTER: Elvas F 

PROVIDER: S-EPMC4641155 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature