Here, the effect of treatment with growth-inhibitory doses of the anti-human epidermal growth factor receptor-2 antibody trastuzumab (Herceptin) on the incorporation of FDG by breast tumor cells was measured along with hexokinase (HK) and glucose transport to determine the potential of FDG-positron emission tomography in predicting response to these biological anti-cancer therapies and their modulatory effects on the steps involved in FDG incorporation.
Methods:
The sensitivity to trastuzumab of three breast tumor cell lines, SKBr3, MDA-MB-453 and MDA-MB-468, expressing human epidermal growth factor receptor-2 at high, medium and low levels, respectively, was determined using MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] JSH-23 manufacturer assay over a 6-day period, and a clonogenic assay was carried out after 7- and 10-day exposures. FDG incorporation by cells treated with growth-inhibitory doses of trastuzumab was carried out after 4 h and 2,4 and 6 days of treatment. Glucose transport (rate of uptake of the non-metabolizable analogue [H-3]O-methyl-D-glucose), HK activity and lactate production were measured on cells treated with inhibitory doses of trastuzumab for 6 days.
Results: The IC50 doses for SKBr3 and MDA-MB-453 and the IC20 dose for MDA-MB-468 after 6 days of treatment
with trastuzumab were 0.25, 1 and 170 mu g/ml, respectively. FDG incorporation by SKBr3 and MDA-MB-453 cells was found to be decreased using IC50 doses of trastuzumab for 6 days. At the IC50 doses, FDG incorporation Entospletinib manufacturer was also decreased at 4 days and, in the case of MDA-MB-453, even after 4 h of treatment. Decreased FDG incorporation corresponded with decreased HK activity in these cells. Lactate production, previously suggested to be a potential measure of response, was
found to be significantly decreased by SKBr3 and MDA-MB-453 cells responding to trastuzumab.
Conclusion: FDG incorporation at the tumor cell level is modulated by treatment with growth-inhibitory doses of trastuzumab due to modulation of HK activity. Changes in lactate production may also be a useful determinant of response to trastuzumab. (C) 2011 Elsevier Inc. All rights reserved.”
“In Plasma membrane Ca2+ ATPase FDG-PET for abdominal malignancy, the liver may be assumed as an internal standard for grading abnormal FDG uptake both in early images and in delayed images. However, physiological variables of FDG uptake by the liver, especially the effects of blood glucose level, have not yet been elucidated.
Methods: FDG-PET studies of 70 patients examined at 50 to 70 min after injection (60 +/- 10 min: early images) and of 68 patients examined at 80 to 100 min after injection (90 +/- 1)) min: delayed images) were analyzed for liver FDG uptake.