Project description:Purpose: Building a universal genomic signature predicting the intensity of FDG uptake in diverse metastatic tumors may allow us to understand better the biological processes underlying this phenomenon and their requirements of glucose uptake. Methods: A balanced training set (n=71) of metastatic tumors including some of the most frequent histologies, with matched PET/CT quantification measurements and whole human genome gene expression microarrays, was used to build the signature. Selection of microarray features was carried out exclusively on the basis of their strong association with FDG uptake (as measured by SUVmean35) by means of univariate linear regression. A thorough bioinformatics study of these genes was performed and multivariable models were built by fitting several state of the art regression techniques to the training set for comparison. Results: The 909 probes with the strongest association with the SUVmean35 (comprising 742 identifiable genes and 62 probes not matched to a symbol) were used to build the signature. Partial Least Squares using 3 components (PLS-3) was the best performing model in the training dataset cross-validation (Root Mean Square Error, RMSE=0.443) and was validated further in an independent validation dataset (n=13) obtaining a performance within the 95% CI of that obtained in the training dataset (RMSE=0.645). Significantly overrepresented biological processes correlating with the SUVmean35 were identified beyond glycolysis, such as ribosome biogenesis and DNA replication (correlating with a higher SUVmean35), and cytoskeleton reorganization and autophagy (correlating with a lower SUVmean35), among others. Conclusions: PLS-3 is a signature predicting accurately the intensity of FDG uptake in diverse metastatic tumors. FDG-PET might help in the design of specific targeted therapies directed to counteract the identified malignant biological processes more likely activated in a tumor as inferred from the SUVmean35 and also from its variations in response to antineoplastic treatments.
Project description:BackgroundBuilding a universal genomic signature predicting the intensity of FDG uptake in diverse metastatic tumors may allow us to understand better the biological processes underlying this phenomenon and their requirements of glucose uptake.MethodsA balanced training set (n = 71) of metastatic tumors including some of the most frequent histologies, with matched PET/CT quantification measurements and whole human genome gene expression microarrays, was used to build the signature. Selection of microarray features was carried out exclusively on the basis of their strong association with FDG uptake (as measured by SUVmean35) by means of univariate linear regression. A thorough bioinformatics study of these genes was performed, and multivariable models were built by fitting several state of the art regression techniques to the training set for comparison.ResultsThe 909 probes with the strongest association with the SUVmean35 (comprising 742 identifiable genes and 62 probes not matched to a symbol) were used to build the signature. Partial least squares using three components (PLS-3) was the best performing model in the training dataset cross-validation (root mean square error, RMSE = 0.443) and was validated further in an independent validation dataset (n = 13) obtaining a performance within the 95% CI of that obtained in the training dataset (RMSE = 0.645). Significantly overrepresented biological processes correlating with the SUVmean35 were identified beyond glycolysis, such as ribosome biogenesis and DNA replication (correlating with a higher SUVmean35) and cytoskeleton reorganization and autophagy (correlating with a lower SUVmean35).ConclusionsPLS-3 is a signature predicting accurately the intensity of FDG uptake in diverse metastatic tumors. FDG-PET might help in the design of specific targeted therapies directed to counteract the identified malignant biological processes more likely activated in a tumor as inferred from the SUVmean35 and also from its variations in response to antineoplastic treatments.
Project description:The standardized uptake value (SUV), an indicator of the glucose uptake degree in 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), has been used as a prognostic factor in malignant tumors. We aimed to identify a signature reflecting prognostic SUV characteristics in breast cancer (BRC). Transcriptome profiling was performed to identify a signature associated with the SUV in BRC patients who underwent preoperative FDG-PET. We defined a signature consisting of 723 genes significantly correlated with the SUV (|r| > .35; P < .001). The patient subgroups classified by the signature were significantly similar to those classified by the SUV (odds ratio, 8.02; 95% CI, 2.45 to 29.3; P < 0.001). The SUV signature showed independent clinical utility for predicting BRC prognosis (hazard ratio, 1.25; 95% CI, 1.11 to 1.42; P < 0.001). Integrative analysis demonstrated a significance of the signature in predicting the response to immunotherapy and revealed that a signaling axis defined by TP53-FOXM1 and its downstream effectors in glycolysis-gluconeogenesis, including LDHA, might be important mediators in the FDG-PET process. Our results reveal characteristics of glucose uptake captured by FDG-PET, supporting an understanding of glucose metabolism as well as poor prognosis in BRC patients with a high SUV.
Project description:The standardized uptake value (SUV), an indicator of the glucose uptake degree in 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), has been used as a prognostic factor in malignant tumors. We aimed to identify a signature reflecting prognostic SUV characteristics in triple negative breast cancer (TNBC). Transcriptome profiling was performed to identify a signature associated with the SUV in TNBC patients who underwent preoperative FDG-PET. We defined a signature significantly associated with the SUV (|r| > .35; P < .01). The SUV signature showed independent clinical utility for predicting BRC prognosis. Integrative analysis demonstrated a significance of the signature in predicting the response to immunotherapy and revealed that a signaling axis defined by TP53-FOXM1 and its downstream effectors in glycolysis-gluconeogenesis, including LDHA, might be important mediators in the FDG-PET process. Our results reveal characteristics of glucose uptake captured by FDG-PET, supporting an understanding of glucose metabolism as well as poor prognosis in TNBC patients with a high SUV.
Project description:1. Background
1. PET/CT (positron emission tomography/computed tomography) using FDG (fluorodeoxyglucose) is widely used for evaluation of cancer patients.
2. Bowel uptake of FDG is a serious problem that hampers the proper reading of PET/CT.
3. There is no widely-accepted method to reduce the bowel FDG uptake.
2. Purpose
1. To know whether pinverin (pinaverium bromide) application during PET/CT can reduce bowel uptake of FDG.
2. Pinverin is a calcium-channel blocker that ameliorates the bowel contraction.
3. Pinverin may be useful to reduce bowel FDG uptake by ameliorating the bowel contraction during PET/CT acquisition.
3. Method
1. Intervention versus control: administration of single tablet of pinverin (50mg) perorally versus simple water (~100mL).
2. Timing of administration: At the time of FDG injection. PET/CT images will be acquired 1hr post FDG injection.
4. Primary outcome
1. SUV (standardized uptake value) difference between pinverin administered patient group versus control group.
2. SUV (standardized uptake value) is calculated as: (decay corrected radioactivity in mCi/mL) x (body weight in g) / (injected radioactivity in mCi)
Project description:Rationale: Estrogens attenuate cardiac hypertrophy and increase cardiac contractility via their cognate receptors ERα and ERβ. Since female sex hormones enhance global glucose utilization and because myocardial function and mass are tightly linked to cardiac glucose metabolism we tested the hypothesis that expression and activation of the estrogen receptor α (ERα) might be required and sufficient to maintain physiological cardiac glucose uptake in the murine heart. Methods and Results: Cardiac glucose uptake quantified in vivo by 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) was strongly impaired in ovarectomized compared to gonadal intact female C57BL/6JO mice. The selective ERα agonist 16α-LE2 and the non-selective ERα and ERβ agonist 17β-estradiol completely restored cardiac glucose uptake in ovarectomized mice. Cardiac FDG uptake was strongly decreased in female ERα knockout mice (ERKO) compared to wild type littermates. Biochemical assays, affymetrix cDNA array analysis, western blotting and immuno-staining of cardiac glucose transporters revealed a positive correlation of ERα dependent cardiac FDG uptake with preserved cardiac glucose transporter-1 expression and micro-vascular localization. Conclusions: Systemic activation of the ERα estrogen receptor is sufficient and its expression is required to maintain physiological glucose uptake in the murine heart, which is likely to contribute to known cardio-protective estrogen effects. total samples analysed are 20
Project description:Microglia is dynamically reprogrammed according to the progression of Alzheimer’s disease (AD). However, clinical translation into biomarker development for functional change in microglia has not been achieved. Here, we find the close association of the metabolic reconfiguration of microglia with increased hippocampal glucose uptake, which can be noninvasively estimated by [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET). We found that increased FDG activity in the hippocampus of an AD mouse model depended on microglial uptake. Single-cell RNA-sequencing of the hippocampus showed the changes of glucose metabolism profiles including glucose transporters, glycolysis and oxidative phosphorylation mainly occurred in microglia. A subset of microglia with high glucose transporters with defective glycolysis and oxidative phosphorylation was increased according to disease progression. Furthermore, we also found a positive association between a soluble TREM2 of cerebrospinal fluid, a marker of microglial activation, and hippocampal FDG uptake as a human study. We identified a reconfiguration of microglial glucose metabolism in the hippocampus of AD and suggested a feasible imaging biomarker based on widely used FDG PET to reflect microglial metabolic profiles.
Project description:Rationale: Estrogens attenuate cardiac hypertrophy and increase cardiac contractility via their cognate receptors ERα and ERβ. Since female sex hormones enhance global glucose utilization and because myocardial function and mass are tightly linked to cardiac glucose metabolism we tested the hypothesis that expression and activation of the estrogen receptor α (ERα) might be required and sufficient to maintain physiological cardiac glucose uptake in the murine heart. Methods and Results: Cardiac glucose uptake quantified in vivo by 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) was strongly impaired in ovarectomized compared to gonadal intact female C57BL/6JO mice. The selective ERα agonist 16α-LE2 and the non-selective ERα and ERβ agonist 17β-estradiol completely restored cardiac glucose uptake in ovarectomized mice. Cardiac FDG uptake was strongly decreased in female ERα knockout mice (ERKO) compared to wild type littermates. Biochemical assays, affymetrix cDNA array analysis, western blotting and immuno-staining of cardiac glucose transporters revealed a positive correlation of ERα dependent cardiac FDG uptake with preserved cardiac glucose transporter-1 expression and micro-vascular localization. Conclusions: Systemic activation of the ERα estrogen receptor is sufficient and its expression is required to maintain physiological glucose uptake in the murine heart, which is likely to contribute to known cardio-protective estrogen effects.
Project description:Although FDG-PET is widely used in cancer, its role in gastric cancer (GC) is still controversial due to variable [18F]fluorodeoxyglucose ([18F]FDG) uptake. Here, we investigate the molecular landscape of GC and its association with glucose metabolic profiles noninvasively evaluated by [18F]FDG PET. Based on a genetic signature, PETscore, representing [18F]FDG avidity, was developed by imaging data acquired from thirty patient-derived xenografts (PDX). Five genes, PLS1, PYY, HBQ1, SLC6A5, NAT16, were identified for the PETscore, which was validated in independent cohorts by qRT-PCR and RNA-sequencing. By applying the PETscore on the Cancer Genome Atlas (TCGA), a significant association between glucose uptake and tumor mutational burden as well as genomic alterations was identified in GC. Our findings suggest that molecular characteristics are underlying the diverse metabolic profiles of GC. Diverse glucose metabolic profiles may apply to precise diagnostic and therapeutic approaches for GC.
Project description:Tumor glucose uptake was measured by FDG-PET in 859 patients with histologically diverse cancers. We used normal mixture modeling to explore FDG-PET standardized uptake values (SUV) distributions and tested for association between glucose uptake and histological differentiation, risk of lymph node metastasis, and survival. Using RNA-seq data, we performed pathway and transcription factor analyses to compare tumors with high and low levels of glucose uptake. We found that well-differentiated tumors had low FDG uptake, while moderately and poorly differentiated tumors had higher uptake. The distribution of SUV for each histology was bimodal with a low peak at SUV 2-4 and a high peak at SUV 8-11. The cancers in the two modes were clinically distinct in terms of the risk of nodal metastases and of death. Carbohydrate metabolism and the pentose related pathway were elevated in the poorly differentiated/high SUV clusters. Embryonic stem cell-related signatures were activated in poorly differentiated/ high SUV clusters.