Search

Context Nicotinamide adenine dinucleotide (NAD) levels decline with aging and age-related decline in NAD has been postulated to contribute to age-related diseases. Objective We evaluated the safety and physiologic effects of NAD augmentation by administering its precursor, β-nicotinamide mononucleotide (MIB-626, Metro International Biotech, Worcester, MA), in adults at risk for age-related conditions. Methods Thirty overweight or obese adults, ≥ 45 years, were randomized in a 2:1 ratio to 2 MIB-626 tablets each containing 500 mg of microcrystalline β-nicotinamide mononucleotide or placebo twice daily for 28 days. Study outcomes included safety; NAD and its metabolome; body weight; liver, muscle, and intra-abdominal fat; insulin sensitivity; blood pressure; lipids; physical performance, and muscle bioenergetics. Results Adverse events were similar between groups. MIB-626 treatment substantially increased circulating concentrations of NAD and its metabolites. Body weight (difference −1.9 [−3.3, −0.5] kg, P = .008); diastolic blood pressure (difference −7.01 [−13.44, −0.59] mmHg, P = .034); total cholesterol (difference −26.89 [−44.34, −9.44] mg/dL, P = .004), low-density lipoprotein (LDL) cholesterol (−18.73 [−31.85, −5.60] mg/dL, P = .007), and nonhigh-density lipoprotein cholesterol decreased significantly more in the MIB-626 group than placebo. Changes in muscle strength, muscle fatigability, aerobic capacity, and stair-climbing power did not differ significantly between groups. Insulin sensitivity and hepatic and intra-abdominal fat did not change in either group. Conclusions MIB-626 administration in overweight or obese, middle-aged and older adults safely increased circulating NAD levels, and significantly reduced total LDL and non-HDL cholesterol, body weight, and diastolic blood pressure. These data provide the rationale for larger trials to assess the efficacy of NAD augmentation in improving cardiometabolic outcomes in older adults.

BackgroundThere is a lack of well validated biomarkers in osteosarcoma, a rare, recalcitrant disease with variable outcome and poorly understood biologic behavior, for which treatment standards have stalled for decades. The only standard prognostic factor in osteosarcoma remains the amount of pathologic necrosis following pre-operative chemotherapy, which does not adequately capture the biologic complexity of the tumor and has not resulted in optimized patient therapeutic stratification. New, robust biomarkers are needed to understand prognosis and better reflect the underlying biologic and molecular complexity of this disease.MethodsWe performed microRNA sequencing in 74 frozen osteosarcoma biopsy samples, the largest single center translationally analyzed cohort to date, and separately analyzed a multi-omic dataset from a large (n = 95) NCI supported national cooperative group cohort. Molecular patterns were tested for association with outcome and used to identify novel therapeutics for further study by integrative pharmacogenomic analysis.ResultsMicroRNA profiles were found predict Recurrence Free Survival (5-microRNA profile, Median RFS 59 vs 202 months, log rank p=0.06, HR 1.87, 95% CI 0.96-3.66). The profiles were independently prognostic of RFS when controlled for metastatic disease at diagnosis and pathologic necrosis following chemotherapy in multivariate Cox proportional hazards regression (5-microRNA profile, HR 3.31, 95% CI 1.31–8.36, p=0.01). Strong trends for survival discrimination were observed in the independent NCI dataset, and transcriptomic analysis revealed the downstream microRNA regulatory targets are also predictive of survival (median RFS 17 vs 105 months, log rank p=0.007). Additionally, DNA methylation patterns held prognostic significance. Through machine learning based integrative pharmacogenomic analysis, the microRNA biomarkers identify novel therapeutics for further study and stratified application in osteosarcoma.ConclusionsOur results support the existence of molecularly defined phenotypes in osteosarcoma associated with distinct outcome independent of clinicopathologic features. We validated candidate microRNA profiles and their associated molecular networks for prognostic value in multiple independent datasets. These networks may define previously unrecognized osteosarcoma subtypes with distinct molecular context and clinical course potentially appropriate for future application of tailored treatment strategies in different patient subgroups.

Significance TCR mechanosensing is thought necessary for digital sensitivity of αβT cell response to scant pMHC antigens. We use bioinformatic analysis, molecular dynamics, single-molecule optical tweezers techniques, cellular activation, and RNA-seq analysis to explore this paradigm in the γδT cell lineage. We find that, in keeping with its role in recognizing abundant cell-surface ligands, the γδTCR lacks force-dependent hallmarks of mechanosensing in αβT cells., High-acuity αβT cell receptor (TCR) recognition of peptides bound to major histocompatibility complex molecules (pMHCs) requires mechanosensing, a process whereby piconewton (pN) bioforces exert physical load on αβTCR–pMHC bonds to dynamically alter their lifetimes and foster digital sensitivity cellular signaling. While mechanotransduction is operative for both αβTCRs and pre-TCRs within the αβT lineage, its role in γδT cells is unknown. Here, we show that the human DP10.7 γδTCR specific for the sulfoglycolipid sulfatide bound to CD1d only sustains a significant load and undergoes force-induced structural transitions when the binding interface-distal γδ constant domain (C) module is replaced with that of αβ. The chimeric γδ–αβTCR also signals more robustly than does the wild-type (WT) γδTCR, as revealed by RNA-sequencing (RNA-seq) analysis of TCR-transduced Rag2−/− thymocytes, consistent with structural, single-molecule, and molecular dynamics studies reflective of γδTCRs as mediating recognition via a more canonical immunoglobulin-like receptor interaction. Absence of robust, force-related catch bonds, as well as γδTCR structural transitions, implies that γδT cells do not use mechanosensing for ligand recognition. This distinction is consonant with the fact that their innate-type ligands, including markers of cellular stress, are expressed at a high copy number relative to the sparse pMHC ligands of αβT cells arrayed on activating target cells. We posit that mechanosensing emerged over ∼200 million years of vertebrate evolution to fulfill indispensable adaptive immune recognition requirements for pMHC in the αβT cell lineage that are unnecessary for the γδT cell lineage mechanism of non-pMHC ligand detection.

Human serum albumin (HSA) acts as a carrier for testosterone, other sex hormones, fatty acids, and drugs. However, the dynamics of testosterone’s binding to HSA and the structure of its binding sites remain incompletely understood. Here, we characterize the dynamics of testosterone’s binding to HSA and the stoichiometry and structural location of the binding sites using 2-dimensional nuclear magnetic resonance (2D NMR), fluorescence spectroscopy, 4,4′-dianilino-1,1′-binaphthyl-5,5′-disulfonic acid dipotassium salt partitioning, and equilibrium dialysis, complemented by molecular modeling. 2D NMR studies showed that testosterone competitively displaced 18-[13C]-oleic acid from at least 3 known fatty acid binding sites on HSA that also bind many drugs. Binding isotherms of testosterone’s binding to HSA generated using fluorescence spectroscopy and equilibrium dialysis were nonlinear and the apparent dissociation constant varied with different concentrations of testosterone and HSA. The binding isotherms neither conformed to a linear binding model with 1:1 stoichiometry nor to 2 independent binding sites; the binding isotherms were most consistent with 2 or more allosterically coupled binding sites. Molecular dynamics studies revealed that testosterone’s binding to fatty acid binding site 3 on HSA was associated with conformational changes at site 6, indicating that residues in in these 2 distinct binding sites are allosterically coupled. There are multiple, allosterically coupled binding sites for testosterone on HSA. Testosterone shares these binding sites on HSA with free fatty acids, which could displace testosterone from HSA under various physiological states or disease conditions, affecting its bioavailability.

Objective The human adaptive fasting response enables survival during periods of caloric deprivation. A crucial component of the fasting response is the shift from glucose metabolism to utilization of lipids, underscoring the importance of adipose tissue as the central lipid-storing organ. The objective of this study was to investigate the response of adipose tissue to a prolonged fast in humans. Methods We performed RNA sequencing of subcutaneous adipose tissue samples longitudinally collected during a 10-day, 0-calorie fast in humans. We further investigated observed transcriptional signatures utilizing cultured human monocytes and Thp1 cells. We examined the cellularity of adipose tissue biopsies with transmission electron microscopy and tested for associated changes in relevant inflammatory mediators in the systemic circulation by ELISA assays of longitudinally collected blood samples. Results Coincident with the expected shift away from glucose utilization and lipid storage, we demonstrated downregulation of pathways related to glycolysis, oxidative phosphorylation, and lipogenesis. The canonical lipolysis pathway was also downregulated, whereas fasting drove alternative lysosomal paths to lipid digestion. Unexpectedly, the dominant induced pathways were associated with immunity and inflammation, although this only became evident at the 10-day time point. Among the most augmented transcripts were those associated with macrophage identity and function, such as members of the erythroblast transformation-specific (ETS) transcription factor family. Key components of the macrophage transcriptional signal in fasting adipose tissue were recapitulated with induced expression of two of the ETS transcription factors via cultured macrophages, SPIC and SPI1. The inflammatory signal was further reflected by an increase in systemic inflammatory mediators. Conclusions Collectively, this study demonstrates an unexpected role of metabolic inflammation in the human adaptive fasting response., Highlights • Prolonged fasting drives an inflammatory transcriptome in human subcutaneous fat. • Fasting induction of a macrophage signature includes the transcription factor SPIC. • SPIC expression in macrophages recapitulates aspects of the fasting transcriptome. • Prolonged fasting drives circulating markers of systemic inflammation. • Fasting drives lysosomal pathways, while canonical lipolysis pathways are attenuated.

Significance Standard of care for metastatic castration-resistant prostate cancer (mCRPC) mainly relies on suppression of androgen receptor (AR) signaling. This approach has no lasting benefit due to the emergence of resistance mechanisms, such as ligand-independent splicing variant AR-V7. A metabolic feature of mCRPC is the upregulation of de novo lipogenesis to provide substrates and fuel for metastatic spread. Whether increased levels of fats affect AR signaling to promote an aggressive disease remains to be determined. Using a selective and potent inhibitor of fatty acid synthase we demonstrate that suppression of this key enzyme inhibits AR, most importantly AR-V7, and reduces mCRPC growth. Our findings offer a therapeutic opportunity for mCRPC and a potential mechanism to overcome resistance to AR inhibitors., A hallmark of prostate cancer progression is dysregulation of lipid metabolism via overexpression of fatty acid synthase (FASN), a key enzyme in de novo fatty acid synthesis. Metastatic castration-resistant prostate cancer (mCRPC) develops resistance to inhibitors of androgen receptor (AR) signaling through a variety of mechanisms, including the emergence of the constitutively active AR variant V7 (AR-V7). Here, we developed an FASN inhibitor (IPI-9119) and demonstrated that selective FASN inhibition antagonizes CRPC growth through metabolic reprogramming and results in reduced protein expression and transcriptional activity of both full-length AR (AR-FL) and AR-V7. Activation of the reticulum endoplasmic stress response resulting in reduced protein synthesis was involved in IPI-9119–mediated inhibition of the AR pathway. In vivo, IPI-9119 reduced growth of AR-V7–driven CRPC xenografts and human mCRPC-derived organoids and enhanced the efficacy of enzalutamide in CRPC cells. In human mCRPC, both FASN and AR-FL were detected in 87% of metastases. AR-V7 was found in 39% of bone metastases and consistently coexpressed with FASN. In patients treated with enzalutamide and/or abiraterone FASN/AR-V7 double-positive metastases were found in 77% of cases. These findings provide a compelling rationale for the use of FASN inhibitors in mCRPCs, including those overexpressing AR-V7.

In Vitro fertilization (IVF) is a widely accepted method for attaining pregnancy in sub-fertile couples. A primary step in IVF is controlled ovarian hyperstimulation (COHS) by reproductive hormones, including Follicle Stimulating Hormone (FSH), to stimulate the production of eggs that can be harvested for IVF. However, there is substantial variation in women’s response to the COHS protocol: almost 40% of patients either respond poorly (15 eggs). Suboptimal response can reduce the chances of pregnancy while ovarian hyperstimulation can be associated with serious health consequences for the patient. Thus, there is an unmet need for algorithms that can help predict response to controlled ovarian hyperstimulation for IVF and help guide treatment decisions. We hypothesized that ovarian response is related to and modulated by several host-level variables, such as age, body mass index (BMI), luteinizing hormone (LH), follicle stimulating hormone (FSH), antral follicular count, anti-Mullerian Hormone (AMH) and estradiol concentrations, that have been shown in previous studies to be associated with the number of oocytes produced (outcome) during COHS. Therefore, we posited that entrained neural networking algorithms that simultaneously take into account these host level variables can be used to predict ovarian response in individual patients. Accordingly, we used a neural network training platform to predict ovarian response using baseline characteristics of IVF patients including age, BMI, smoking status and initial estrogen levels. Linear and multilayer neural network regressors were executed with 80% of data used for training and 20% for prediction testing. From the 441 observations, optimized artificial neural network accurately predicted oocyte number for 71% of women within ±1 eggs SD. The performance of the ANN will be presented in comparison to alternative models. Conclusion: Artificial Neural Networking Algorithms can be entrained and used to predict ovarian responses in subfertile patients undergoing IVF. Additional research is needed to optimize input parameters and predictive value of such algorithms in guiding personalized protocols for controlled ovarian hyperstimulation during IVF.

Background: We reported higher serum free testosterone (FT) and increased anal-HPV16/18 infection prevalence in MSM. Associations between serum-FT and -estradiol and anal-HPV16/18 infections and histological HSIL (hHSIL) are unclear. Methods: Two cross-sectional analyses were performed. 340 HIV-infected/HIV-uninfected Multicenter AIDS Cohort MSM were tested for anal HPVs; another 214 men were evaluated using HRA/biopsy with multiple assessments for some totaling 336 HRAs. Serum specimens collection preceded HPV and HRA visits by 24(+9) months and were tested for albumin, SHBG (radioimmunoassay), and total testosterone and estradiol (TE2) (LC/MS); serum-FT (pg/mL) was estimated. Anal swabs were tested for 37 HPVs (PCR) and classified: HPV16/18+, other Group-1 and -2 high-risk HPVs+ (hrHPVs); low-risk HPVs+ (lrHPVs), vs. none. Biopsies were evaluated as hHSIL vs.

Regulation of lineage-restricted transcription factors has been shown to influence malignant transformation in several types of cancer. Whether similar mechanisms are involved in ovarian cancer pathogenesis is unknown. PAX8 is a nuclear transcription factor that controls the embryologic development of the Mullerian system, including the fallopian tubes. Recent studies have shown that fallopian tube secretory epithelial cells (FTSECs) give rise to the most common form of ovarian cancer, high-grade serous ovarian carcinomas (HGSOCs). We designed the present study in order to understand whether changes in gene expression between FTSECs and HGSOCs relate to alterations in PAX8 binding to chromatin. Using whole transcriptome shotgun sequencing (RNA-Seq) after PAX8 knockdown and ChIP-Seq, we show that FTSECs and HGSOCs are distinguished by marked reprogramming of the PAX8 cistrome. Genes that are significantly altered between FTSECs and HGSOCs are enriched near PAX8 binding sites. These sites are also near TEAD binding sites, and these transcriptional changes may be related to PAX8 interactions with the TEAD/YAP1 signaling pathway. These data suggest that transcriptional changes after transformation in ovarian cancer are closely related to epigenetic remodeling in lineage-specific transcription factors.

Mammalian genomes encode a large number of non-coding RNAs (ncRNAs) that greatly exceed mRNA genes. While the physiological and pathological roles of ncRNAs have been increasingly understood, the mechanisms of regulation of ncRNA expression are less clear. Here, our genomic study has shown that a significant number of long non-coding RNAs (lncRNAs, >1,000 nucleotides) harbor RNA polymerase II (Pol II) engaged with the transcriptional start site. A pausing and transcriptional elongation factor for protein-coding genes, tripartite motif-containing 28 (TRIM28) regulates the transcription of a subset of lncRNAs in mammalian cells. In addition, the majority of lncRNAs in human and murine cells regulated by Pol II promoter-proximal pausing appear to function in stimulus-inducible biological pathways. Our findings suggest an important role of Pol II pausing for the transcription of mammalian lncRNA genes.

We have previously shown that RNA polymerase II (Pol II) pause release and transcriptional elongation involve phosphorylation of the factor TRIM28 by the DNA damage response (DDR) kinases ATM and DNA-PK. Here we report a significant role for DNA breaks and DDR signalling in the mechanisms of transcriptional elongation in stimulus-inducible genes in humans. Our data show the enrichment of TRIM28 and γH2AX on serum-induced genes and the important function of DNA-PK for Pol II pause release and transcriptional activation-coupled DDR signalling on these genes. γH2AX accumulation decreases when P-TEFb is inhibited, confirming that DDR signalling results from transcriptional elongation. In addition, transcriptional elongation-coupled DDR signalling involves topoisomerase II because inhibiting this enzyme interferes with Pol II pause release and γH2AX accumulation. Our findings propose that DDR signalling is required for effective Pol II pause release and transcriptional elongation through a novel mechanism involving TRIM28, DNA-PK and topoisomerase II., RNA polymerase II (Pol II) pause release and transcriptional elongation involve phosphorylation of TRIM28 by the DNA damage response (DDR) kinases. Here, Bunch et al. show that DDR signalling is coupled with and required for transcriptional elongation in stimulus-inducible genes and involves topoisomerase II.