Figure 9: Cell Adhesion Status Influences Cellular Energetic State and

Schematic illustrating the relationship between energetics and 99mTc-pertechnetate uptake in adherent and suspended cells. Glycolysis is the main ATP-generating metabolic pathway in proliferating cells. Cell dissociation/suspension leads to reduced surface expression of GLUT1, reduced glucose uptake and glycolytic flux with consequent reduction in cellular ATP levels. NIS expression permits cellular transport of 99mTc-pertechnectate, which is coupled to Na+-K+-ATPase activity, and modulated by cellular ATP levels. Suspended cells have down-regulation of glycolysis, lower cellular ATP levels, and lower 99mTc-pertechnectate uptake, when compared with adherent cells. Abbreviations as in Figure 1.