Preliminary application of micro‐SPECT/CT imaging by ^99mTc‐tricine‐EDDA‐HYNIC‐c‐Met for non‐small‐cell lung cancer

Abstract

Objective A novel 99mTc‐tricine‐EDDA‐Hynic‐c‐Met molecular probe was synthetized, and nude mice models of human non‐small‐cell lung cancer (NSCLC) were established in order to preliminarily investigate that whether the molecular probe can be used to screen c‐Met inhibitor for targeted drug therapy in NSCLC. Methods With Hynic as the chelating agent, 99mTcO4‐labeled c‐Met receptor was used to synthetize 99mTc‐tricine‐EDDA‐HYNIC‐c‐Met. Two nude mice successfully transplanted with H1993 tumor and two nude mice transplanted with H292 tumor were injected with 99mTc‐tricine‐EDDA‐HYNIC‐c‐Met through the tail vein. After 2 and 4 hr, micro‐SPECT/CT imaging was performed. Results micro‐SPECT/CT imaging of nude mice transplanted with H1993 and H292 tumors using 99mTc‐tricine‐EDDA‐HYNIC‐c‐Met showed that uptake of 99mTc‐tricine‐EDDA‐HYNIC‐c‐Met was high in H1993 tumor, while it was mild in H292 tumor both at 2 and 4 hr postinjection. Semiquantitative analysis of the ratio of radioactivity intensity at tumor site to radioactivity intensity of adjacent muscles (T/N value) showed that the average T/N value of H1993 and H292 tumors at 2 hr was 3.90 and 2.85, while it was 4.88 and 2.36 at 4 hr. Conclusion micro‐SPECT/CT imaging through 99mTc‐tricine‐EDDA‐HYNIC‐c‐Met can be used to screen c‐Met indicators of NSCLC in H1993 nude mice models for targeted drug therapy.

Micro-CT acquisition and image processing to track and characterize pulmonary nodules in mice

“…Single photon emission computed tomography (SPECT) and positron emission tomography (PET) can be used to detect lung cancers and can provide molecular and metabolic activity of tumours [35][36][37][38] , but their limitations are poor spatial resolution (≤1 mm in SPECT 39 and >1 mm in PET) 40 , long scanning time and require the use of radioisotopes. Depending on the amount of radioactivity injected, the scanning time for SPECT imaging is 10 -50 min per animal [41][42][43] and PET imaging is 15 -60 min per animal [44][45][46][47] .To co-register detailed anatomical localisation with molecular information, commercial small animal SPECT (e.g., nanoScan SPECT/CT, Mediso), PET (e.g., nanoScan PET/CT, Mediso) and optical (e.g., IVIS SpectrumCT, PerkinElmer) imaging scanners are usually integrated x-ray CT inside the same imaging gantry or platform.…”