gw9662 and Neoplasms

(18)F-2-deoxy-2-fluoro-d-glucose ((18)F-FDG) positron emission tomography (PET) has been used for imaging human cancers for several decades. Despite its extensive use, (18)F-FDG PET imaging has limitations in the tumor findings. The goal of this study was to investigate the potential of a PPAR-γ agonist pioglitazone (PIO) to distinguish tumors and inflammatory lesions in (18)F-FDG PET imaging.. Studies of cellular uptake of (18)F-FDG and Western blot were performed in macrophage (RAW264.7) and three tumor cell lines (A549, KB, and MDA-MB-231) after treatment with PIO. In vivo microPET/CT imaging and biodistribution were performed in animal models.. The uptake of (18)F-FDG in the macrophages was decreased and uptake of (18)F-FDG in the tumor cells was increased when these cells were treated with PIO. Western blot showed that the expression of Glut1 was reduced by treatment of PIO in the macrophage cells, whereas the expression of Glut1 in the tumor cells was increased. In vivo PET/CT imaging revealed that (18)F-FDG uptake (%ID/g) in the tumors was enhanced from 4.05±1.46 to 5.28±1.92 for A549, from 3.9±0.5 to 4.9±0.2 for KB, and from 9.14±0.86 to 13.48±2.07 for MDA-MB-231 tumors after treatment with PIO. Unlike tumors, the RAW264.7 xenograft model showed the reduced (18)F-FDG uptake in the inflammatory lesion from 11.74±1.19 to 6.50±1.47. The results of biodistribution also showed that (18)F-FDG uptake in the tumors were increased after treatment of PIO. However, the uptake of inflammation lesions was reduced.. In this study, we demonstrated the effect of a PPAR-γ agonist PIO on (18)F-FDG uptake in tumors and inflammation in vitro and in vivo. PIO has potential to differentiate tumors and inflammatory lesions on (18)F-FDG PET imaging.

Topics: Anilides; Animals; Biological Transport; Cell Line, Tumor; Diagnosis, Differential; Female; Fluorodeoxyglucose F18; Gene Expression Regulation, Neoplastic; Glucose; Glucose Transporter Type 1; Glucose Transporter Type 3; Humans; Inflammation; Macrophages; Mice; Neoplasms; Pioglitazone; Positron-Emission Tomography; PPAR gamma; Thiazolidinediones; Tissue Distribution

The identification of self-renewing and multipotent neural stem cells (NSCs) in the mammalian brain holds promise for the treatment of neurological diseases and has yielded new insight into brain cancer. However, the complete repertoire of signaling pathways that governs the proliferation and self-renewal of NSCs, which we refer to as the 'ground state', remains largely uncharacterized. Although the candidate gene approach has uncovered vital pathways in NSC biology, so far only a few highly studied pathways have been investigated. Based on the intimate relationship between NSC self-renewal and neurosphere proliferation, we undertook a chemical genetic screen for inhibitors of neurosphere proliferation in order to probe the operational circuitry of the NSC. The screen recovered small molecules known to affect neurotransmission pathways previously thought to operate primarily in the mature central nervous system; these compounds also had potent inhibitory effects on cultures enriched for brain cancer stem cells. These results suggest that clinically approved neuromodulators may remodel the mature central nervous system and find application in the treatment of brain cancer.

Topics: Animals; Cell Survival; Cells, Cultured; Mice; Molecular Structure; Neoplasms; Neurons; Pharmaceutical Preparations; Sensitivity and Specificity; Stem Cells