Pattern of F-18 FDG Uptake in Colon Cancer after Bacterial Cancer Therapy Using Engineered Salmonella Typhimurium: A Preliminary In Vivo Study

Figure 1

Study overview. This pilot study was performed using two separate trials: A and B. A tumor was generated in the right thigh of each mouse (BALB/c female mice, 6-weeks-old) using the murine CT26 colon adenocarcinoma cells. After tumor volume reached approximately 180 mm³, BCT was performed by intravenous injection of bacterial cells via the tail vein (CFU/mouse in 100 μL PBS). Two trials were designed to avoid animal preparation issues such as fasting and general anesthesia. In trial A (), FDG PET/CT images were acquired at 0 dpi, 2 dpi, 10 dpi, and 16 dpi (a). In trial B (), FDG PET/CT images were acquired at 0 dpi, 1 dpi, 4 dpi, 7 dpi, and 15 dpi (b). In vivo BLi confirming the presence of tumor-targeting bacteria was performed at 2 dpi, immediately after PET/CT in trial A, and immediately after each PET/CT in trial B. Abbreviations: FDG, 2-deoxy-2[¹⁸F]fluoro-D-glucose; dpi, days post-injection; SUVmax, maximum standardized uptake value; SUVmean, mean standardized uptake value; PBS, phosphate-buffered saline; CFU, colony-forming units; BLi, bioluminescence imaging.

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