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In this work, we investigated the NAD(P)-dependent dehydrogenase activity in different fields of the solid form of Ehrlich carcinoma. It was shown that there is a metabolic distinction between different fields of the solid tumor. In this way, there is a significant difference between the ascites and solid type of Ehrlich carcinoma. In the central area of the tested sample of tumor tissue, there is a high intensity of energetic metabolism and biosynthetic processes as opposed to the peripheral areas. Previously, we proposed the concept of nonspecific metabolic reaction of the cell in organism upon the influence of negative factors. In accordance with this concept, our results indicate the development of adaptation in the tumor cells in the central area of the tested sample.

Glioblastoma (GBM) stem cells (GSCs) reside in both hypoxic and vascular microenvironments within tumors. The molecular mechanisms that allow GSCs to occupy such contrasting niches are not understood. We used patient-derived GBM cultures to identify GSC subtypes with differential activation of Notch signaling, which co-exist in tumors but occupy distinct niches and match their metabolism accordingly. Multipotent GSCs with Notch pathway activation reside in perivascular niches, and are unable to entrain anaerobic glycolysis during hypoxia. In contrast, most CD133-expressing GSCs do not depend on canonical Notch signaling, populate tumors regardless of local vascularity and selectively utilize anaerobic glycolysis to expand in hypoxia. Ectopic activation of Notch signaling in CD133-expressing GSCs is sufficient to suppress anaerobic glycolysis and resistance to hypoxia. These findings demonstrate a novel role for Notch signaling in regulating GSC metabolism and suggest intratumoral GSC heterogeneity ensures metabolic adaptations to support tumor growth in diverse tumor microenvironments.

// Gloria Bonuccelli 1 , Ernestina Marianna De Francesco 1,2 , Rianne de Boer 1 , Herbert B. Tanowitz 3 and Michael P. Lisanti 4 1 The Paterson Building, University of Manchester, Withington, M20 4BX, United Kingdom 2 Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, Rende, 87036, Italy 3 Departments of Pathology and Medicine, Albert Einstein College of Medicine, Bronx, NY, 10461, USA 4 Translational Medicine, School of Environment and Life Sciences, Biomedical Research Centre, University of Salford, Greater Manchester, M5 4WT, United Kingdom Correspondence to: Michael P. Lisanti, email: // Gloria Bonuccelli, email: // Keywords : cancer stem-like cells; metabolic heterogeneity; metabolic cell fractionation; mitochondria; NADH Received : January 10, 2017 Accepted : January 25, 2017 Published : February 16, 2017 Abstract Here, we assembled a broad molecular “tool-kit” to interrogate the role of metabolic heterogeneity in the propagation of cancer stem-like cells (CSCs). First, we subjected MCF7 cells to “metabolic fractionation” by flow cytometry, using fluorescent mitochondrial probes to detect PCG1α activity, as well ROS and hydrogen-peroxide (H2O2) production; NADH levels were also monitored by auto-fluorescence. Then, the various cell populations were functionally assessed for “stem cell activity”, using the mammosphere assay (3D-spheroids). Our results indicate that a sub-population of MCF7 cells, with increased PGC1α activity, high mitochondrial ROS/H2O2 production and high NADH levels, all form mammospheres with a higher efficiency. Thus, it appears that mitochondrial oxidative stress and the anti-oxidant response both contribute to the promotion of mitochondrial biogenesis and oxidative metabolism in CSCs. Further validation was provided by using specific inhibitors to target metabolic processes (the NAD+ salvage pathway, glycolysis, mitochondrial protein synthesis and OXPHOS), significantly reducing CSC propagation. As a consequence, we have now identified a variety of clinically-approved drugs (stiripentol), natural products (caffeic acid phenyl ester (CAPE), ascorbic acid, silibinin) and experimental pharmaceuticals (actinonin, FK866, 2-DG), that can be used to effectively inhibit CSC activity. We discuss the use of CAPE (derived from honey-bee propolis) and Vitamin C, as potential natural therapeutic modalities. In this context, Vitamin C was ~10 times more potent than 2-DG for the targeting of CSCs. Similarly, stiripentol was between 50 to 100 times more potent than 2-DG.

Measurement of intratumoral heterogeneity by 18F-fluorodeoxyglucose (18F-FDG) Positron Emission Tomography (PET) is a valuable modality, which showed correlation to response of treatment and prognosis in various malignancies. PET-based texture analysis for tumor heterogeneity is a potential predictive factor for cervical cancer and related to lymph node metastasis, tumor volume, response of treatment, and pelvic recurrence. Although seemed promising in utility in oncology, a plenty of methods have been used for analysis of heterogeneity which led to confusion of definitions and comparing results challenging. Further larger sized prospective studies are needed for standardized heterogeneity descriptors and clinical applications.

Dajiang is a popular Chinese fermented soybean condiment. Here, a comparative metaproteomic analysis of traditional and commercial dajiang was performed during fermentation. A total of 4250 and 1421 peptide sequences were obtained from 3493 and 1987 proteins in traditional and commercial dajiang, respectively. 4299 differentially expressed microbial proteins show a high metabolic heterogeneity between the two types of dajiang. The KEGG annotation indicated that there were some pathways related to human diseases, which suggest that some microbes in traditional dajiang fermentation may have greater food safety hazards. In combination with qualitative metabolomic analysis, we further traced metabolic intermediates and key enzymes in several main fermentation pathways of dajiang to be mainly affiliated with Penicillium, Tetracoccus and Bacillus in traditional samples, as well as Aspergilus in commercial samples. These results could provide information for the selection of strains that are more suitable to produce high quality dajiang and other fermented products.

Tumor functional heterogeneity has been recognized for decades, and technological advancements are fueling renewed interest in uncovering the cell-intrinsic and extrinsic factors that influence tumor development and therapeutic response. Intratumoral heterogeneity is now arguably one of the most-studied topics in tumor biology, leading to the discovery of new paradigms and reinterpretation of old ones, as we aim to understand the profound implications that genomic, epigenomic, and functional heterogeneity hold with regard to clinical outcomes. In spite of our improved understanding of the biological complexity of cancer, characterization of tumor metabolic heterogeneity has lagged behind, lost in a century-old controversy debating whether glycolysis or mitochondrial respiration is more influential. But is tumor metabolism really so simple? Here, we review historical and current views of intratumoral heterogeneity, with an emphasis on summarizing the emerging data that begin to illuminate just how vast the spectrum of metabolic strategies a tumor can employ may be, and what this means for how we might interpret other tumor characteristics, such as mutational landscape, contribution of microenvironmental influences, and treatment resistance.

311 Background: Metabolic intratumoral heterogeneity (ITH) is known to be related with cancer treatment outcome. However, information on the temporal changes in metabolic ITH during chemotherapy and the correlations between metabolic changes and treatment outcomes in patients with pancreatic cancer (PC) is sparse. We aimed to analyze the temporal changes in metabolic ITH and the predictive role of its changes in advanced PC patients who underwent palliative chemotherapy. Methods: We prospectively enrolled unresectable locally advanced or metastatic PC patients before initiation of first-line palliative chemotherapy. 18F-fluorodeoxyglucose positron emission tomography was performed at baseline (T1) and at the first response follow-up (T2). Standardized uptake values (SUVs), volumetric parameters, and textural features of the primary pancreatic tumor were analyzed. Relationships between the parameters at T1, T2, and changes in the parameters with response to therapy, progression-free survival (PFS), and overall survival (OS) were assessed. Results: Among 63 enrolled patients, the best objective response rate was 25.8% (95% confidence interval [CI], 14.6% to 37.0%). Sixteen (25.8%) patients who obtained partial response were classified as responders and 46 (74.2%) as nonresponders. The median PFS and OS were 7.1 months (95% CI, 5.1 to 9.7 months) and 10.1 months (95% CI, 8.6 to 12.7 months), respectively. Most of the parameters changed significantly during the first-line chemotherapy, in a way of reducing ITH. Metabolic ITH was more profoundly reduced in responders than in nonresponders. Multiple Cox regression analysis identified high baseline compacity ( P = 0.023) and smaller decreases in SUVpeak ( P = 0.007) and entropyGLCM ( P = 0.033) to be independently associated with poor PFS. Patients with a high CA 19-9 ( P = 0.042), high pretreatment SUVpeak ( P = 0.008), and high coefficient of variance at T2 ( P = 0.04) showed worse OS. Conclusions: Reduction in metabolic ITH during palliative chemotherapy in advanced PC patients is associated with response to therapy and might be predictive of PFS and OS.

The number of studies in the literature involving quantification of the metabolic heterogeneity seen in 18F-FDG PET images has increased sharply over recent years. We hypothesized that inclusion of very small regions of interest as unique data points will have deleterious effects on these studies. Methods: Using a combination of probability theory and clinical 18F-FDG PET data, we numerically calculated the curve describing the probability a given tumor volume is large enough to adequately sample the underlying tumor biology assayed via a PET/CT scanner at a planar resolution of 4 mm and transaxial resolution of 4 mm (64 mm3 voxel size). We then used a computer simulation to isolate the effects of tumor volume on the image local entropy. Results: We computed the underlying global intensity distribution for 70 cervical cancer tumors ranging from 4 to 248 cm3), which were ensemble-averaged over the same intensity scale. From this distribution, we determined that about 700 total voxels (45 cm3) are required to give 95% certainty that the global intensity distribution has been sufficiently sampled for common statistical comparisons of individual tumor intensity distributions to be made canonically. We demonstrated that one previously suggested measure of heterogeneity is dependent on tumor volume and that measurement of heterogeneity is about 5 times more sensitive to volume changes for volumes below the proposed minimum than for those above it. Conclusion: Inclusion of tumor volumes below 45 cm3 can profoundly bias comparisons of intratumoral uptake heterogeneity metrics derived from data from the current generation of whole-body 18F-FDG PET scanners.

We evaluated the value of variable (18)F-FDG PET/CT parameters for the prediction of disease progression after concurrent chemoradiotherapy (CCRT) in patients with inoperable stage III non-small-cell lung cancer (NSCLC).One hundred sixteen pretreatment FDG PET/CT scans of inoperable stage III NSCLC were retrospectively reviewed (stage IIIA: 51; stage IIIB: 65). The volume of interest was automatically drawn for each primary lung tumor, and PET parameters were assessed as follows: maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV) using the boundaries presenting SUV intensity exceeding 3.0, and the area under the curve of the cumulative SUV-volume histograms (AUC-CSH), which is known to reflect the tumor heterogeneity. Progression-free survival (PFS), locoregional recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) were compared with each PET and clinical parameters by univariate and multivariate survival analysis.In the ROC analysis, the optimal cutoff values of SUVmax, MTV (cm(3)), and AUC-CSH for prediction of PFS were determined as 21.5, 27.7, and 4,800, respectively. In univariate analysis, PFS was statistically significantly reduced in those with AUC-CSH 4,800 (p = 0.004). In multivariate analysis, AUC-CSH and SUVmax were statistically significant independent prognostic factors (HR 3.35, 95 % CI 1.79-6.28, p 0.001; HR 0.25, 95 % CI 0.09-0.70, p = 0.008, respectively). Multivariate analysis showed that AUC-CSH was the most significant independent prognostic factor for LRFS and DMFS (HR 3.27, 95 % CI 1.54-6.94, p = 0.002; HR 2.79, 95 % CI 1.42-5.50, p = 0.003).Intratumoral metabolic heterogeneity of primary lung tumor in (18)F-FDG PET/CT can predict disease progression after CCRT in inoperable stage III NSCLC.

Understanding metabolism in live microalgae is crucial for efficient biomaterial engineering, but conventional methods fail to evaluate heterogeneous populations of motile microalgae due to the labelling requirements and limited imaging speeds. Here, we demonstrate label-free video-rate metabolite imaging of live Euglena gracilis and statistical analysis of intracellular metabolite distributions under different culture conditions. Our approach provides further insights into understanding microalgal heterogeneity, optimizing culture methods and screening mutant microalgae. Label-free, video-rate metabolite imaging of live Euglena gracilis shows spatiotemporal intracellular metabolite distributions under different culture conditions.

Molecular signatures are emerging determinants of choice of therapy for lung adenocarcinomas. An evolving therapeutic approach includes targeting metabolic dependencies in cancers. Here, using an integrative approach, we have dissected the metabolic fingerprints of lung adenocarcinomas, and we show that Phosphoglycerate dehydrogenase (PHGDH), the rate-limiting enzyme in serine biosynthesis, is highly expressed in a adenocarcinoma subset with poor prognosis. This subset harbors a gene signature for DNA replication and proliferation. Accordingly, models with high levels of PHGDH display rapid proliferation, migration, and selective channeling of serine-derived carbons to glutathione and pyrimidines, while depletion of PHGDH shows potent and selective toxicity to this subset. Differential PHGDH protein levels were defined by its degradation, and the deubiquitinating enzyme JOSD2 is a regulator of its protein stability. Our study provides evidence that a unique metabolic program is activated in a lung adenocarcinoma subset, described by PHGDH, which confers growth and survival and may have therapeutic implications.

Aging is a complex biological process with remarkable individual variation and manifests also as changes in systemic metabolism. In a recent paper in PNAS, Chaleckis et al. (1) studied a set of blood metabolites in old and young individuals. The work was thorough in the methodological aspects regarding the mass spectrometry of circulating molecules in plasma, red blood cells, and whole blood. However, we find it alarming that the results and interpretations on the suggested age-related metabolic differences were not properly put into epidemiological context. We therefore draw attention to four key issues: ( i ) metabolic heterogeneity of … [↵][1]1To whom correspondence should be addressed. Email: ville-petteri.makinen{at}sahmri.com. [1]: #xref-corresp-1-1

Imaging of hyperpolarized substrates by magnetic resonance shows great clinical promise for assessment of critical biochemical processes in real time. Due to fundamental constraints imposed by the hyperpolarized state, exotic imaging and reconstruction techniques are commonly used. A practical system for characterization of dynamic, multi-spectral imaging methods is critically needed. Such a system must reproducibly recapitulate the relevant chemical dynamics of normal and pathological tissues. The most widely utilized substrate to date is hyperpolarized [1-(13)C]-pyruvate for assessment of cancer metabolism. We describe an enzyme-based phantom system that mediates the conversion of pyruvate to lactate. The reaction is initiated by injection of the hyperpolarized agent into multiple chambers within the phantom, each of which contains varying concentrations of reagents that control the reaction rate. Multiple compartments are necessary to ensure that imaging sequences faithfully capture the spatial and metabolic heterogeneity of tissue. This system will aid the development and validation of advanced imaging strategies by providing chemical dynamics that are not available from conventional phantoms, as well as control and reproducibility that is not possible in vivo.

In the brain, glycogen metabolism has been implied in synaptic plasticity and learning, yet the distribution of this molecule has not been fully described. We investigated cerebral glycogen of the mouse by immunohistochemistry (IHC) using two monoclonal antibodies that have different affinities depending on the glycogen size. The use of focused microwave irradiation yielded well-defined glycogen immunoreactive signals compared with the conventional periodic acid-Schiff method. The IHC signals displayed a punctate distribution localized predominantly in astrocytic processes. Glycogen immunoreactivity (IR) was high in the hippocampus, striatum, cortex, and cerebellar molecular layer, whereas it was low in the white matter and most of the subcortical structures. Additionally, glycogen distribution in the hippocampal CA3-CA1 and striatum had a 'patchy' appearance with glycogen-rich and glycogen-poor astrocytes appearing in alternation. The glycogen patches were more evident with large-molecule glycogen in young adult mice but they were hardly observable in aged mice (1-2 years old). Our results reveal brain region-dependent glycogen accumulation and possibly metabolic heterogeneity of astrocytes. GLIA 2016;64:1532-1545.

A hybrid multiscale mathematical model of tumor growth is used to investigate how tumoral and microenvironmental heterogeneity affect the response of the immune system. The model includes vascular dynamics and evolution of metabolic tumor phenotypes. Cytotoxic T cells are simulated, and their effect on tumor growth is shown to be dependent on the structure of the microenvironment and the distribution of tumor phenotypes. Importantly, no single immune strategy is best at all stages of tumor growth.

Metabolism underlies many important cellular decisions, such as the decisions to proliferate and differentiate, and defects in metabolic signaling can lead to disease and aging. In addition, metabolic heterogeneity can have biological consequences, such as differences in outcomes and drug susceptibilities in cancer and antibiotic treatments. Many approaches exist for characterizing the metabolic state of a population of cells, but technologies for measuring metabolism at the single cell level are in the preliminary stages and are limited. Here, we describe novel analysis methodologies that can be applied to established experimental methods to measure metabolic variability within a population. We use mass spectrometry to analyze amino acid composition in cells grown in a mixture of (12)C- and (13)C-labeled sugars; these measurements allow us to quantify the variability in sugar usage and thereby infer information about the behavior of cells within the population. The methodologies described here can be applied to a large range of metabolites and macromolecules and therefore have the potential for broad applications.

Optical metabolic imaging (OMI) quantifies the fluorescence intensities and lifetimes of NADH and FAD using two-photon microscopy. OMI monitors single cells in tumors, thus aiding in the development and implementation of effective cancer treatments.

Gastrointestinal stromal tumors (GISTs) and malignant lymphomas (MLs) in the abdomen are often observed as tumors of unknown origin on F-18 FDG PET/CT. The purpose of this study was to evaluate the intratumoral metabolic heterogeneity of F-18 FDG uptake on PET to determine if it might be helpful to discriminate between these tumors.The F-18 FDG PET/CT findings of 21 large abdominal tumors were retrospectively evaluated (9 GISTs and 12 MLs). Intratumoral heterogeneity was evaluated by visual scoring (visual score: 0, homogeneous; 1, slightly heterogeneous; 2, moderately heterogeneous; 3, highly heterogeneous) and by the cumulative standardized uptake value (SUV) histograms on transaxial PET images at the maximal cross-sectional tumor diameter. Percent tumor areas above a threshold from 0 to 100% of the maximum SUV were plotted and the area under curve of the cumulative SUV histograms (AUC-CSH) was used as a heterogeneity index, where lower values corresponded with increased heterogeneity. Correlation between the visual score and the AUC-CSH was investigated by the Spearman's rank test.GISTs exhibited heterogeneous uptake of F-18 FDG, whereas MLs showed rather homogeneous uptake on visual analysis (visual score: 2.67 ± 0.50 and 0.58 ± 0.79, respectively; p 0.001). The AUC-CSH was significantly lower for the GISTs than for the MLs (0.41 ± 0.14 and 0.64 ± 0.08, respectively; p 0.001). Significant correlations were observed between the visual score and the AUC-CSH (ρ = -0.866, p 0.001).GISTs exhibited significantly heterogeneous intratumoral tracer uptake as compared with the MLs. Evaluation of the intratumoral heterogeneity of F-18 FDG uptake may help in the discrimination between these tumors.

Recent discoveries suggest that cells of a clonal population often display multiple metabolic phenotypes at the same time. Motivated by the success of mass spectrometry (MS) in the investigation of population-level metabolomics, the analytical community has initiated efforts towards MS-based single cell metabolomics to investigate metabolic phenomena that are buried under the population average. Here, we review the current approaches and illustrate their advantages and disadvantages. Because of significant advances in the field, different technologies are now at the verge of generating data that are useful for exploring and investigating metabolic heterogeneity.

The highly heterogeneous nature of glioblastoma (GBM) is a hallmark of limited response to the current therapies and subsequent unfavorable clinical prognosis. Although intratumoral cellular heterogeneity has been recognized in various cancers including GBM, the spatial distributions of tumor-associated cell types and their mechanisms of metabolic pathways that are essential for their heterogeneity remain poorly understood. Here, we utilized the MRI-guided localized biopsy of GBM tumor tissues during surgery, thereby establishing multiple patient-derived GBM clones from both the tumor core and edge tissues in a clonal density, termed core-GBM clones and edge-GBM clones. Using these GBM clones as well as the original tumor tissues, we investigated the underlying molecular mechanisms that drive spatial metabolic heterogeneity in GBM. Comprehensive single cell-metabolome analysis revealed a clear difference between the core and edge clones, as well as between the core and edge tissues. In particular, we noticed metabolic heterogeneity in the nicotinamide adenine dinucleotide (NAD) pathway between the core-GBM clones/tissues and the edge-GBM clones/tissues. Manipulation of the NAD pathway showed distinct phenotypic changes among these clones. These findings suggest that metabolic heterogeneity plays an essential role in therapeutic resistance of glioblastoma.

Proteomic platforms provide quantitative snapshots of the proteins present in a biological sample. Despite widespread use, these methods typically require homogenization of samples, signal-averaging over thousands-to-millions of cells and provide no information on protein function. This talk will focus on several novel technologies to circumvent these limitations and to interrogate protein activity within the complex architecture of biological samples, and on spatial scales ranging from single cells to whole organisms. At the single cell level we have developed a chemical proteomic technology, activity-dependent proximity ligation, which enables multiplexed quantification of enzyme activity with high spatial resolution in cellular co-culture and in patient tissue samples. Application of this platform has enabled detection of several metastasis-associated biomarker activities in primary patient samples, as well as simultaneous detection of activity and mRNA expression profiles. These data provide insight into the progression lineage of metastatic ovarian cancers. On the other end of the spectrum, we have recently developed a first-in-class activity-dependent PET imaging probe that specifically and irreversibly labels one of these enzyme biomarkers in vivo. This provides an opportunity to detect aggressive tumor populations, both at sites of primary occurrence and metastasis, with this novel PET radiotracer. Together, these approaches offer new paradigms for studying protein function in basic and translational biology and medicine, ideally providing new tools and biological hypotheses to understand and target tumor malignancy. Citation Format: Raymond E. Moellering. Chemical proteomic platforms to probe metabolic heterogeneity in the tumor microenvironment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5664.

Introduction Familial combined hyperlipidaemia (FCH) and familial hypercholesterolaemia (FH) have been strongly linked to premature coronary artery disease. Postprandial hypertriglyceridaemia is also associated with atherosclerotic disease. We evaluated the postprandial lipaemia in men with FCH and FH and compared them to a group of healthy men. Material and methods The study population consisted of 83 men: 34 FCH, 29 FH and 20 healthy. The FCH and FH groups were further divided into five subgroups, according to their lipid phenotype: FCH-IIA (n = 13), FCH-IIB (n = 10), FCH-IV (n = 11), FH-IIA (n = 21) and FH-IIB (n = 8). Postprandial lipaemia was evaluated by the areas under the curve for triglyceride (TG) concentrations (TG-AUC). Results The TG levels after oral fat tolerance test were significantly higher in FCH, compared to FH and healthy groups (TG-AUC in mg/dl/h; 2678 ±1415 vs. 1503 ±1147 and 1011 ±652 respectively, p < 0.001). The postprandial response was higher in FCH-IV and FCH-IIB, compared to FCH-IIA (TG-AUC in mg/dl/h; 3220 ±824 or 3409 ±770 vs. 1863 ±577 respectively, p < 0.001, for both comparisons). The FCH-IIA group showed higher postprandial TG levels when compared to FH-IIA (TG-AUC in mg/dl/h; 1863 ±577 vs. 1374 ±428 respectively, p = 0.008). There were no significant differences between FH-IIB and FCH-IIB subgroups. There was a significant correlation (r = 0.907, p < 0.001) between the postprandial TG-AUC and fasting TG levels in all FCH subjects. Conclusions All phenotypes of FCH and the FH IIB phenotype demonstrate an exaggerated postprandial response that could partially contribute to the high cardiovascular risk. These patients should be identified and treated early with the appropriate hypolipidaemic agents.

Purpose: Previous research has shown that the intertumoral maximum standardized uptake value (SUVMax) of F-18 fluorodeoxyglucose (FDG)–positron emission tomography (PET) for cervical cancer predicts disease outcome. The purpose of this study was to evaluate the pretreatment intratumoral metabolic heterogeneity of FDG. Experimental Design: This is a prospective cohort study of 72 patients with International Federation of Gynecology and Obstetrics stages Ib1 to IVa cervical cancer treated with chemoradiation. Three-dimensional FDG-PET threshold tumor volumes were calculated using image segmentation and an adaptive thresholding method for the primary cervix tumor from the pretreatment FDG-PET/computerized tomography. Intratumor heterogeneity was obtained for each patient's cervical tumor by taking the derivative (dV/dT) of the volume-threshold function from 40% to 80%. The association between intratumoral heterogeneity and tumor-specific factors and patient outcomes were determined. Results: The mean cervix tumor SUVMax was 12.4 (range, 3.0-38.4). The mean differential tumor heterogeneity was −1.074 (range, −0.107 to −5.623). There was no association between dV/dT and SUVMax (R2 = 0.069), but there was a relationship with dV/dT and tumor volume (R2 = 0.881). There was no correlation of dV/dT with tumor histology (P = 0.4905). Heterogeneity was significantly associated with the risk of lymph node metastasis at diagnosis (P = 0.0009), tumor response to radiation as evaluated by FDG-PET obtained 3 months after completing treatment (P = 0.0207), risk of pelvic recurrence (P = 0.0017), and progression-free survival (P = 0.03). Conclusions: Cervical intratumoral FDG metabolic heterogeneity on the pretreatment FDG-PET predicts risk of lymph node involvement at diagnosis, response to therapy, and risk of pelvic recurrence.

Previously, we identified two distinct metabonomic phenotypes in Sprague-Dawley rats sourced from two different rooms (colonies) in the Charles River, Raleigh facility [Robosky, L. C., Wells, D. F., Egnash, L. A., Manning, M. L., Reily, M. D., and Robertson, D. G. (2005) Metabonomic identification of two distinct phenotypes in Sprague-Dawley (Crl:CD(SD)) rats. Toxicol. Sci. 87, 277-284]. On the basis of literature reports and cohabitation experiments, we concluded that the differing phenotypes were due to different gut flora populations. One hypothesis explaining this phenomenon was attributed to the practice of initiating new colonies with rats derived from foundation colonies that had limited gut floral populations, the Charles River altered Schaedler flora (CRASF) rats. We hypothesized that the lack of differentiation of CRASF rats to the full complement of microflora was responsible for the altered phenotype characterized by increased urinary chlorogenic acid metabolites and decreased hippurate (CA rats) as opposed to the prevalent phenotype characterized by the inverse ratio of these metabolites (HIP rats). Upon receipt, it was confirmed that the CRASF rats exhibited a metabonomic profile similar to CA rats that remained constant while animals were housed individually in a dedicated animal room. However, exposure of CRASF rats to HIP rats, or their bedding, led to a relatively rapid but variable rate of reversion to the historic HIP type metabolic profile. On the basis of the results, we conclude that CRASF rats have a unique metabolic profile due to their limited gut flora constitution. If rigorous isolation procedures are not employed, the CRASF phenotype will eventually differentiate into the more typical HIP phenotype with a time course that may be quite variable. Given the marked metabolic heterogeneity between the phenotypes, this work highlights the importance of monitoring rat metabolic profiles.

Background: Intratumoral heterogeneity is a well-recognized characteristic feature of cancer. The purpose of this study is to assess the heterogeneity of the intratumoral glucose metabolism using fractal analysis, and evaluate its prognostic value in patients with esophageal squamous cell carcinoma (ESCC). Methods: 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) studies of 79 patients who received curative surgery were evaluated. FDG-PET images were analyzed using fractal analysis software, where differential box-counting method was employed to calculate the fractal dimension (FD) of the tumor lesion. Maximum standardized uptake value (SUVmax) and FD were compared with overall survival (OS). Results: The median SUVmax and FD of ESCCs in this cohort were 13.8 and 1.95, respectively. In univariate analysis performed using Cox's proportional hazard model, T stage and FD showed significant associations with OS (p = 0.04, p < 0.0001, respectively), while SUVmax did not (p = 0.1). In Kaplan-Meier analysis, the low FD tumor (Conclusion: Metabolic heterogeneity measured by fractal analysis can be a novel imaging biomarker for survival in patients with ESCC.

Pancreatic cancer stem cells (CSCs) display a distinct metabolic phenotype based on their strong dependence on mitochondrial oxidative phosphorylation (OXPHOS) and limited metabolic plasticity. While suppression of MYC upstream of PGC-1α was the key determinant of this phenotype, we also identified a subset of CSCs with reduced mitochondrial content that showed resistance to mitochondrial targeting, but could be sensitized by inhibition of MYC.

We describe chemical approaches for integrated metabolic and proteomic assays from single cells. Quantitative assays for intracellular metabolites, including glucose uptake and three other species, are designed as surface-competitive binding assays with fluorescence readouts. This enables integration into a microarray format with functional protein immunoassays, all of which are incorporated into the microchambers of a single-cell barcode chip (SCBC). By using the SCBC, we interrogate the response of human-derived glioblastoma cancer cells to epidermal growth factor receptor inhibition. We report, for the first time, on both the intercellular metabolic heterogeneity as well as the baseline and drug-induced changes in the metabolite-phosphoprotein correlation network.

Metabolic heterogeneity is a recognized characteristic of malignant tumors. Positron emission tomography (PET) texture analysis evaluated intratumoral heterogeneity in the uptake of (18)F-fluorodeoxyglucose. There were recent evidences that PET textural features were of prognostic significance in patients with different solid tumors. Unfortunately, there are still crucial standardization challenges to transform PET texture parameters from their current use as research tools into the arena of validated technologies for use in oncology practice. Testing its generalizability, robustness, consistency, and limitations is necessary before implementing it in daily patient care.