MIBG inhibits respiration: potential for radio- and hyperthermic sensitization  John E Biaglow, Ph.D., Yefim Manevich, Ph.D., Dennis Leeper, Ph.D., Britton Chance, Ph.D., Mark W Dewhirst, Ph.D., Walter T Jenkins, M.S., Steve W Tuttle, Ph.D., Krzysztof Wroblewski, Ph.D., Jerry D Glickson, Ph.D., Craig Stevens, M.D., Ph.D., Sydney M Evans  International Journal of Radiation Oncology • Biology • Physics  Volume 42, Issue 4, Pages 871-876 (November 1998) DOI: 10.1016/S0360-3016(98)00334-4

Fig. 1 The immediate effect of MIBG on the inhibition of 9L rat glioma cell suspension (1.0 × 107 cells/ml) oxygen consumption in 20 mM PBS, pH = 7.40 at 37°C. Cells were grown in vitro and harvested as described in the methods section. The vertical axis is the relative rate of oxygen consumption. The data represents an average of at least four independent experiments. The error bars represent standard error. Similar results were obtained with tumor cell suspensions isolated from tumor bearing rats (data not shown). International Journal of Radiation Oncology • Biology • Physics 1998 42, 871-876DOI: (10.1016/S0360-3016(98)00334-4)

Fig. 2 The immediate effect of 30 μM of MIBG on fluorescence kinetics of NAD(P)H (excitation at 347 nm and emission at 460 nm) and Fp (excitation at 450 nm and emission at 520 nm) of 9L cells adherent to the quartz slide (14 × 40 mm); 20 mM PBS (50 μM Ca2+ and Mg2+, and 10 mM glucose were added), pH = 7.40, 37°C. The results are the average of five independent experiments. International Journal of Radiation Oncology • Biology • Physics 1998 42, 871-876DOI: (10.1016/S0360-3016(98)00334-4)

Fig. 3 The effect of IP injection of 2.3 ml MIBG (4 mg/ml in 20 mM PBS, pH = 7.40) to 9L glioma-bearing ketamine-xylazine anaesthetized rat (weight 230 g) on kinetics of intracellular pH changes, as detected by 31P-NMR in vivo (see Materials and Methods for details). Line (1) represents the intracellular pH changes of anaesthetized animals without MIBG, and line (2) represents the pH changes after MIBG administration to the same previously anaesthetized animals. The results are the average of six independent measurements with different animals. International Journal of Radiation Oncology • Biology • Physics 1998 42, 871-876DOI: (10.1016/S0360-3016(98)00334-4)

Fig. 4 The statistical treatment of data collected by the two-dimensional redox scanning of 9L glioma (see Materials and Methods for details) cross-sections with detection of intensity distribution of NAD(P)H and Fp. Each selection for statistical treatment contains at least five independent scans. Tumors were removed 1-h after MIBG administration to ketamine/xylazine anesthetized tumor bearing rats. International Journal of Radiation Oncology • Biology • Physics 1998 42, 871-876DOI: (10.1016/S0360-3016(98)00334-4)

Fig. 5 The actual images of two-dimensional redox scanning of frozen 9L glioma tumors harvested from tumor bearing rats. The top images represent the fluorescence intensity distribution of NAD(P)H and Fp in the cross-section of tumor from the anaesthetized animal without MIBG. The bottom images represent the effect of MIBG (4 mg/100 g body weight) on NAD(P)H and Fp intensity distribution in the tumor cross-section. The color changes from violet to white indicate an increase in subsequent fluorescence. International Journal of Radiation Oncology • Biology • Physics 1998 42, 871-876DOI: (10.1016/S0360-3016(98)00334-4)