MYC is an oncogenic driver in the pathogenesis of ovarian cancer. We previously demonstrated that MYC regulates polyamine metabolism in triple-negative breast cancer (TNBC) and that a plasma polyamine signature is associated with TNBC development and progression. We hypothesized that a similar plasma polyamine signature may associate with ovarian cancer (OvCa) development. Using mass spectrometry, four polyamines were quantified in plasma from 116 OvCa cases and 143 controls (71 healthy controls + 72 subjects with benign pelvic masses) (Test Set). Findings were validated in an independent plasma set from 61 early-stage OvCa cases and 71 healthy controls (Validation Set). Complementarity of polyamines with CA125 was also evaluated. Receiver operating characteristic area under the curve (AUC) of individual polyamines for distinguishing cases from healthy controls ranged from 0.74–0.88. A polyamine signature consisting of diacetylspermine + N-(3-acetamidopropyl)pyrrolidin-2-one in combination with CA125 developed in the Test Set yielded improvement in sensitivity at >99% specificity relative to CA125 alone (73.7% vs 62.2%; McNemar exact test 2-sided P: 0.019) in the validation set and captured 30.4% of cases that were missed with CA125 alone. Our findings reveal a MYC-driven plasma polyamine signature associated with OvCa that complemented CA125 in detecting early-stage ovarian cancer.
The nuclear factor erythroid 2-related factor 2 (NRF2) pathway is frequently activated in various cancer types. Aberrant activation of NRF2 in cancer is attributed to gain-of-function mutations in the NRF2-encoding gene NFE2L2 or a loss of function of its suppressor, Kelch-like ECH-associated protein 1 (KEAP1). NRF2 activation exerts pro-tumoral effects in part by altering cancer cell metabolism. Previously, we reported a novel mechanism of NRF2 tumoral immune suppression through the selective upregulation of the tryptophan-metabolizing enzyme kynureninase (KYNU) in lung adenocarcinoma. In the current study, we explored the relevance of NRF2-mediated KYNU upregulation across multiple cancer types. Specifically, using a gene expression dataset for 9801 tumors representing 32 cancer types from The Cancer Genome Atlas (TCGA), we demonstrated that elevated KYNU parallels increased gene-based signatures of NRF2-activation and that elevated tumoral KYNU mRNA expression is strongly associated with an immunosuppressive tumor microenvironment, marked by high expression of gene-based signatures of Tregs as well as the immune checkpoint blockade-related genes CD274 (PDL-1), PDCD1 (PD-1), and CTLA4, regardless of the cancer type. Cox proportional hazard models further revealed that increased tumoral KYNU gene expression was prognostic for poor overall survival in several cancer types, including thymoma, acute myeloid leukemia, low-grade glioma, kidney renal papillary cell carcinoma, stomach adenocarcinoma, and pancreatic ductal adenocarcinoma (PDAC). Using PDAC as a model system, we confirmed that siRNA-mediated knockdown of NRF2 reduced KYNU mRNA expression, whereas activation of NFE2L2 (the coding gene for NRF2) through either small-molecule agonists or siRNA-mediated knockdown of KEAP1 upregulated KYNU in PDAC cells. Metabolomic analyses of the conditioned medium from PDAC cell lines revealed elevated levels of KYNU-derived anthranilate, confirming that KYNU was enzymatically functional. Collectively, our study highlights the activation of the NRF2–KYNU axis as a multi-cancer phenomenon and supports the relevance of tumoral KYNU as a marker of tumor immunosuppression and as a prognostic marker for poor overall survival.
Purpose: Lynch syndrome (LS) is a hereditary condition with a high lifetime risk of colorectal and endometrial cancers. Exercise is a non-pharmacologic intervention to reduce cancer risk, though its impact on patients with LS has not been prospectively studied. Here, we evaluated the impact of a 12-month aerobic exercise cycling intervention in the biology of the immune system in LS carriers. Patients and Methods: To address this, we enrolled 21 patients with LS onto a non-randomized, sequential intervention assignation, clinical trial to assess the effect of a 12-month exercise program that included cycling classes 3 times weekly for 45 minutes versus usual care with a one-time exercise counseling session as control. We analyzed the effects of exercise on cardiorespiratory fitness, circulating, and colorectal-tissue biomarkers using metabolomics, gene expression by bulk mRNA sequencing, and spatial transcriptomics by NanoString GeoMx. Results: We observed a significant increase in oxygen consumption (VO2peak) as a primary outcome of the exercise and a decrease in inflammatory markers (prostaglandin E) in colon and blood as the secondary outcomes in the exercise versus usual care group. Gene expression profiling and spatial transcriptomics on available colon biopsies revealed an increase in the colonic mucosa levels of natural killer and CD8+ T cells in the exercise group that were further confirmed by IHC studies. Conclusions: Together these data have important implications for cancer interception in LS, and document for the first-time biological effects of exercise in the immune system of a target organ in patients at-risk for cancer.
Purpose: Sarcopenia is a hallmark of cancer cachexia. Chimeric antigen receptor (CAR) T-cell therapy is associated with an inflammatory state that may exacerbate sarcopenia. The relationship among CAR T-cell therapy, sarcopenia, and metabolism is poorly understood. Experimental Design: In 83 patients with large B-cell lymphoma, the skeletal muscle index was measured from clinical images obtained at baseline and days 30 and 90 after therapy. Serum metabolomics (n = 57 patients) was performed in the first 4 weeks. Results: Baseline sarcopenia was present in more than half of patients and associated with shorter median overall survival than for non-sarcopenic patients (10.5 vs. 34.3 months; P = 0.006). This reduction was due to increased nonrelapse mortality with all six nonrelapse mortality events occurring in patients with baseline sarcopenia. In the first 30 days after CAR T-cell therapy, one of three patients experienced skeletal muscle loss greater than 10%. Muscle loss was associated with higher tumor burden and neurotoxicity but was not significantly associated with long-term survival. Serum metabolomics revealed an early (weeks 1–2) increase in purine metabolites, followed by a later (weeks 3–4) increase in triglyceride levels. The serum metabolite with the highest fold-increase from baseline was adipic acid, attributed to the inpatient hospital menu of jello and other tart beverages. Conclusions: Skeletal muscle loss after CAR T-cell therapy is common and is associated with fatty acid catabolism. Patients with baseline sarcopenia have poor tolerance and reduced survival. Future studies of dietary and exercise interventions may improve CAR T-cell therapy outcomes.
25 October 2017 in Physical Chemistry Chemical Physics
The gas-phase conformations of the protonated forms of thymidine-5′-monophosphate and uridine-5′-monophosphate, [pdThd+H]+ and [pUrd+H]+, are investigated by infrared multiple photon dissociation (IRMPD) action spectroscopy and electronic structure calculations. The IRMPD action spectra of [pdThd+H]+ and [pUrd+H]+ are measured over the IR fingerprint and hydrogen-stretching regions using the FELIX free electron laser and an OPO/OPA laser system. Low-energy conformations of [pdThd+H]+ and [pUrd+H]+ and their relative stabilities are computed at the MP2(full)/6-311+G(2d,2p)//B3LYP/6-311+G(d,p) and B3LYP/6-311+G(2d,2p)//B3LYP/6-311+G(d,p) levels of theory. Comparisons of the measured IRMPD action spectra and B3LYP/6-311+G(d,p) linear IR spectra computed for the low-energy conformers indicate that the dominant conformers of [pdThd+H]+ and [pUrd+H]+ populated in the experiments are protonated at the phosphate oxo oxygen atom, with a syn nucleobase orientation that is stabilized by strong POH+⋯O2 and P–OH⋯O4′ hydrogen-bonding interactions, and C2′-endo sugar puckering. Minor abundance of conformers protonated at the O2 carbonyl of the nucleobase residue may also contribute for [pdThd+H]+, but do not appear to be important for [pUrd+H]+. Comparisons to previous IRMPD spectroscopy investigations of the protonated forms of thymidine and uridine, [dThd+H]+ and [Urd+H]+, and the deprotonated forms of pdThd and pUrd, [pdThd−H]− and [pUrd−H]−, provide insight into the effects of the phosphate moiety and protonation on the conformational features of the nucleobase and sugar moieties. Most interestingly, the thymine and uracil nucleobases remain in their canonical forms for [pdThd+H]+ and [pUrd+H]+, unlike [dThd+H]+ and [Urd+H]+, where protonation occurs on the nucleobases and induces tautomerization of the thymine and uracil residues.
Purpose: To assess the contributions of circulating metabolites for improving upon the performance of the risk of ovarian malignancy algorithm (ROMA) for risk prediction of ovarian cancer among women with ovarian cysts. Experimental Design: Metabolomic profiling was performed on an initial set of sera from 101 serous and nonserous ovarian cancer cases and 134 individuals with benign pelvic masses (BPM). Using a deep learning model, a panel consisting of seven cancer-related metabolites [diacetylspermine, diacetylspermidine, N-(3-acetamidopropyl)pyrrolidin-2-one, N-acetylneuraminate, N-acetyl-mannosamine, N-acetyl-lactosamine, and hydroxyisobutyric acid] was developed for distinguishing early-stage ovarian cancer from BPM. The performance of the metabolite panel was evaluated in an independent set of sera from 118 ovarian cancer cases and 56 subjects with BPM. The contributions of the panel for improving upon the performance of ROMA were further assessed. Results: A 7-marker metabolite panel (7MetP) developed in the training set yielded an AUC of 0.86 [95% confidence interval (CI): 0.76–0.95] for early-stage ovarian cancer in the independent test set. The 7MetP+ROMA model had an AUC of 0.93 (95% CI: 0.84–0.98) for early-stage ovarian cancer in the test set, which was improved compared with ROMA alone [0.91 (95% CI: 0.84–0.98); likelihood ratio test P: 0.03]. In the entire specimen set, the combined 7MetP+ROMA model yielded a higher positive predictive value (0.68 vs. 0.52; one-sided P < 0.001) with improved specificity (0.89 vs. 0.78; one-sided P < 0.001) for early-stage ovarian cancer compared with ROMA alone. Conclusions: A blood-based metabolite panel was developed that demonstrates independent predictive ability and complements ROMA for distinguishing early-stage ovarian cancer from benign disease to better inform clinical decision making.
About Me
The University of Texas, M.D. Anderson Cancer Center
6767 Bertner Ave. (BSRB S13.8136), Houston, TX, 77030
The University of Texas, M.D. Anderson Cancer Center
6767 Bertner Ave. (BSRB S13.8136), Houston, TX, 77030