ABSTRACT
The Jumonji domain-containing protein-3 (JMJD3) is a histone demethylase that regulates the trimethylation of histone H3 on lysine 27 (H3K27me3). H3K27me3 is an important epigenetic event associated with transcriptional silencing. JMJD3 has been studied extensively in immune diseases, cancer, and tumor development. There is a comprehensive epigenetic transformation during the transition of embryonic stem cells (ESCs) into specialized cells or the reprogramming of somatic cells to induced pluripotent stem cells (iPSCs). Recent studies have illustrated that JMJD3 plays a major role in cell fate determination of pluripotent and multipotent stem cells (MSCs). JMJD3 has been found to enhance self-renewal ability and reduce the differentiation capacity of ESCs and MSCs. In this review, we will focus on the recent advances of JMJD3 function in stem cell fate. Video Abstract.
Subject(s)
Embryonic Stem Cells/metabolism , Epigenesis, Genetic , Induced Pluripotent Stem Cells/metabolism , Jumonji Domain-Containing Histone Demethylases/genetics , Cell Differentiation/genetics , Cell Lineage/genetics , Histone Demethylases/genetics , Histones/genetics , Humans , MethylationABSTRACT
OBJECTIVE: We investigated the correlation between fluorine-18-fluorodeoxyglucose (F-FDG) uptake and glucose transporter-1 (GLUT-1) and hypoxia-inducible factor-1α (HIF-1α) expression in a rabbit lung VX2 tumor model. MATERIALS AND METHODS: Twenty-four VX2 tumor-bearing rabbits underwent F-FDG PET/computed tomography (CT) at 4, 5, 6, and 7 weeks after implantation. PET/CT images were obtained to monitor the tumor/normal tissue (T/N) ratio in each period. Six rabbits were randomly killed after PET/CT, and immunohistochemical staining was used to assess GLUT-1 and HIF-1α expression. We investigated the correlations of F-FDG uptake with GLUT-1 and HIF-1α expression and the pathological tumor (p-tumor) size as well as those of the lymph node metastasis (p-N) stage with the T/N ratio, p-tumor size, and GLUT-1 and HIF-1α expression. RESULTS: The T/N ratio increased gradually over time before subsequently decreasing. The T/N ratio was significantly influenced by time (F=54.63, P<0.05) and was significantly correlated with GLUT-1 (r=0.53, P<0.01) and HIF-1α (r=0.44, P<0.01) expression and p-tumor size (r=0.58, P<0.05). A significant positive correlation between GLUT-1 expression and HIF-1α expression was also identified (r=0.58, P<0.05). The p-N stage showed a significant association with the T/N ratio (P<0.05) but not with GLUT-1/HIF-1α expression (P>0.05). CONCLUSION: F-FDG uptake is closely correlated with GLUT-1 and HIF-1α expression, tumor size, and lymph node metastasis.