Novel two-tiered screening approach identifies synergistic combinations of natural compounds for prostate cancer prevention and treatment.

Prostate cancer (PCa) is the second most common cancer type among American men and it is estimated that in 2023, 34,700 men will die from PCa. Since it can take a considerable amount of time for the disease to progress to clinically evident cancer, there is ample opportunity for effective chemopreventive strategies to be applied for the successful management of PCa progression. In the current study, we have developed a two-tiered metabolomics-based screen to identify synergistic combinations of phytochemicals for PCa chemoprevention. This involves an initial screen for ATP depletion in PCa cells followed by a targeted screen for blocking glutamine uptake in the same cells. One of the phytochemical combinations (enoxolone [ENO] + silibinin [SIL]), identified via this screen, was examined for effects on PCa cell survival, oncogenic signaling and tumor growth in vivo. This combination was found to synergistically reduce cell survival, colony formation and cell cycle progression of PCa cell lines to a greater extent than either agent alone. The combination of ENO and SIL also synergistically reduced tumor growth when administered ad libitum through the diet in a HMVP2 allograft PCa tumor model. Treatment with the combination also significantly reduced STAT3 and mTORC1 signaling pathways in mouse and human PCa cells while significantly reducing levels of critical cell cycle regulatory proteins, contributing to the synergistic inhibition of tumor growth observed. Collectively, the current results demonstrate a novel approach to identifying synergistic combinations of phytochemicals for chemoprevention of PCa and possibly other cancers.

Disruption of dNTP homeostasis by ribonucleotide reductase hyperactivation overcomes AML differentiation blockade.

Differentiation blockade is a hallmark of acute myeloid leukemia (AML). A strategy to overcome such a blockade is a promising approach against the disease. The lack of understanding of the underlying mechanisms hampers development of such strategies. Dysregulated ribonucleotide reductase (RNR) is considered a druggable target in proliferative cancers susceptible to deoxynucleoside triphosphate (dNTP) depletion. Herein, we report an unanticipated discovery that hyperactivating RNR enables differentiation and decreases leukemia cell growth. We integrate pharmacogenomics and metabolomics analyses to identify that pharmacologically (eg, nelarabine) or genetically upregulating RNR subunit M2 (RRM2) creates a dNTP pool imbalance and overcomes differentiation arrest. Moreover, R-loop-mediated DNA replication stress signaling is responsible for RRM2 activation by nelarabine treatment. Further aggravating dNTP imbalance by depleting the dNTP hydrolase SAM domain and HD domain-containing protein 1 (SAMHD1) enhances ablation of leukemia stem cells by RRM2 hyperactivation. Mechanistically, excessive activation of extracellular signal-regulated kinase (ERK) signaling downstream of the imbalance contributes to cellular outcomes of RNR hyperactivation. A CRISPR screen identifies a synthetic lethal interaction between loss of DUSP6, an ERK-negative regulator, and nelarabine treatment. These data demonstrate that dNTP homeostasis governs leukemia maintenance, and a combination of DUSP inhibition and nelarabine represents a therapeutic strategy.

Enzymatic depletion of l-Met using an engineered human enzyme as a novel therapeutic strategy for melanoma.

Many cancers, including melanoma, have a higher requirement for l-methionine in comparison with noncancerous cells. In this study, we show that administration of an engineered human methionine-γ-lyase (hMGL) significantly reduced the survival of both human and mouse melanoma cells in vitro. A multiomics approach was utilized to identify global changes in gene expression and in metabolite levels with hMGL treatment in melanoma cells. There was considerable overlap in the perturbed pathways identified in the two data sets. Common pathways were flagged for further investigation to understand their mechanistic importance. In this regard, hMGL treatment induced S and G2 phase cell cycle arrest, decreased nucleotide levels, and increased DNA double-strand breaks suggesting an important role for replication stress in the mechanism of hMGL effects on melanoma cells. Further, hMGL treatment resulted in increased cellular reactive oxygen species levels and increased apoptosis as well as uncharged transfer RNA pathway upregulation. Finally, treatment with hMGL significantly inhibited the growth of both mouse and human melanoma cells in orthotopic tumor models in vivo. Overall, the results of this study provide a strong rationale for further mechanistic evaluation and clinical development of hMGL for the treatment of melanoma skin cancer and other cancers.

Enzyme-mediated depletion of serum l-Met abrogates prostate cancer growth via multiple mechanisms without evidence of systemic toxicity.

Extensive studies in prostate cancer and other malignancies have revealed that l-methionine (l-Met) and its metabolites play a critical role in tumorigenesis. Preclinical and clinical studies have demonstrated that systemic restriction of serum l-Met, either via partial dietary restriction or with bacterial l-Met-degrading enzymes exerts potent antitumor effects. However, administration of bacterial l-Met-degrading enzymes has not proven practical for human therapy because of problems with immunogenicity. As the human genome does not encode l-Met-degrading enzymes, we engineered the human cystathionine-γ-lyase (hMGL-4.0) to catalyze the selective degradation of l-Met. At therapeutically relevant dosing, hMGL-4.0 reduces serum l-Met levels to >75% for >72 h and significantly inhibits the growth of multiple prostate cancer allografts/xenografts without weight loss or toxicity. We demonstrate that in vitro, hMGL-4.0 causes tumor cell death, associated with increased reactive oxygen species, S-adenosyl-methionine depletion, global hypomethylation, induction of autophagy, and robust poly(ADP-ribose) polymerase (PARP) cleavage indicative of DNA damage and apoptosis.

An IGF-1R-mTORC1-SRPK2 signaling Axis contributes to FASN regulation in breast cancer.

BACKGROUND: Fatty acid synthase (FASN) expression is associated with a more aggressive breast cancer phenotype and is regulated downstream of receptor tyrosine kinase (RTK) signaling pathways. Recently, post transcriptional regulation of lipogenic transcripts have been demonstrated as being mediated downstream of serine-arginine rich protein kinase 2 (SRPK2), which acts to phosphorylate serine-arginine rich splicing factors (SRSFs), resulting in RNA binding and various RNA regulatory processes. Though post-transcriptional regulation of FASN has been studied previously, the upstream mediators of these pathways have not been elucidated. METHODS: Western blotting and RT-qPCR were utilized to demonstrate alterations in FASN and mRNA expression upon modulation of the IGF-1-mTORC1-SRPK2 pathway by small molecule inhibitors or RNAi mediated silencing. RNA stability was accessed by using the transcriptional inhibitor actinomycin-D followed by RT-qPCR. Further, we employed RNA-immunoprecipitation to demonstrate the direct binding of SRSF-1 to FASN transcripts. RESULTS: In the current study, we demonstrated an IGF-1 induced increase in FASN mRNA and protein expression that was attenuated by mTORC1 inhibition. This mTORC1 inhibition also resulted in decreases in total and nuclear p-SRPK2 in response to IGF-1 exposure. Upon SRPK2 knockdown and inhibition, we observed a decrease in FASN protein and mRNA stability, respectively, in response to IGF-1 exposure that was specific to triple negative and HER2+ breast cancer cell lines. As we explored further, IGF-1 exposure resulted in an altered localization of eGFP expressed SRSF-1, pEGFP-SRSF-1 that was rescued upon both SRPK2 knockdown and mTORC1 inhibition. Further, we observed an increase binding of SRSF-1 to FASN RNA upon IGF-1 exposure, which was abrogated by SRPK2 knockdown. CONCLUSION: These current findings establish a potential IGF-1-mTORC1-SRPK2-FASN axis in breast cancer, which could be a potential therapeutic target for cancers that overexpress FASN and components of the IGF-1R pathway.

Nutritional programming by maternal diet alters offspring lipid metabolism in a marine teleost.

Nutritional programming - the association between the early nutritional environment and long-term consequences for an animal - is an emerging area of research in fish biology. Previous studies reported correlations between maternal provisioning of essential fatty acids to eggs and the whole-body fatty acid composition of larvae reared under uniform conditions for red drum, Sciaenops ocellatus. This study aimed to further investigate the nutritional stimulus and the consequences of nutritional programming by feeding adult red drum several distinct diets and rearing larvae under uniform conditions until 21 days post-hatching when larval lipid and fatty acid compositions were assessed. Different maternal diets produced eggs with distinctive lipid and fatty acid compositions, and despite receiving the same larval diet for almost 3 weeks, larvae showed differences in total fatty acid accumulation and in retention of highly unsaturated fatty acids (HUFA). Specifically, larvae reared from a maternal diet of shrimp generally showed elevated levels of fatty acids in the initial steps of the n-3 and n-6 HUFA biosynthetic pathways and reduced levels of fatty acid products of the same pathways, especially in triglyceride. Furthermore, the variations in larval fatty acid accumulation induced by maternal diet varied among females. Lipid metabolism altered by parental diet may have consequences for larval physiological processes and behavioral performance, which may ultimately influence larval survival.

The low molecular weight protein tyrosine phosphatase promotes adipogenesis and subcutaneous adipocyte hypertrophy.

Obesity is a major contributing factor to the pathogenesis of Type 2 diabetes. Multiple human genetics studies suggest that high activity of the low molecular weight protein tyrosine phosphatase (LMPTP) promotes metabolic syndrome in obesity. We reported that LMPTP is a critical promoter of insulin resistance in obesity by regulating liver insulin receptor signaling and that inhibition of LMPTP reverses obesity-associated diabetes in mice. Since LMPTP is expressed in adipose tissue but little is known about its function, here we examined the role of LMPTP in adipocyte biology. Using conditional knockout mice, we found that selective deletion of LMPTP in adipocytes impaired obesity-induced subcutaneous adipocyte hypertrophy. We assessed the role of LMPTP in adipogenesis in vitro, and found that LMPTP deletion or knockdown substantially impaired differentiation of primary preadipocytes and 3T3-L1 cells into adipocytes, respectively. Inhibition of LMPTP in 3T3-L1 preadipocytes also reduced adipogenesis and expression of proadipogenic transcription factors peroxisome proliferator activated receptor gamma (PPARγ) and CCAAT/enhancer-binding protein alpha. Inhibition of LMPTP increased basal phosphorylation of platelet-derived growth factor receptor alpha (PDGFRα) on activation motif residue Y849 in 3T3-L1, resulting in increased activation of the mitogen-associated protein kinases p38 and c-Jun N-terminal kinase and increased PPARγ phosphorylation on inhibitory residue S82. Analysis of the metabolome of differentiating 3T3-L1 cells suggested that LMPTP inhibition decreased cell glucose utilization while enhancing mitochondrial respiration and nucleotide synthesis. In summary, we report a novel role for LMPTP as a key driver of adipocyte differentiation via control of PDGFRα signaling.

Novel Strategy for Untargeted Chiral Metabolomics using Liquid Chromatography-High Resolution Tandem Mass Spectrometry.

Stereospecific recognition of metabolites plays a significant role in the detection of potential disease biomarkers thereby providing new insights in diagnosis and prognosis. D-Hdroxy/amino acids are recognized as potential biomarkers in several metabolic disorders. Despite continuous advances in metabolomics technologies, the simultaneous measurement of different classes of enantiomeric metabolites in a single analytical run remains challenging. Here, we develop a novel strategy for untargeted chiral metabolomics of hydroxy/amine groups (-OH/-NH2) containing metabolites, including all hydroxy acids (HAs) and amino acids (AAs), by chiral derivatization coupled with liquid chromatography-high resolution tandem mass spectrometry (LC-HR-MS/MS). Diacetyl-tartaric anhydride (DATAN) was used for the simultaneous derivatization of-OH/-NH2 containing metabolites as well as the resulting diastereomers, and all the derivatized metabolites were resolved in a single analytical run. Data independent MS/MS acquisition (DIA) was applied to positively identify DATAN-labeled metabolites based on reagent specific diagnostic fragment ions. We discriminated chiral from achiral metabolites based on the reversal of elution order of D and L isomers derivatized with the enantiomeric pair (±) of DATAN in an untargeted manner. Using the developed strategy, a library of 301 standards that consisted of 214 chiral and 87 achiral metabolites were separated and detected in a single analytical run. This approach was then applied to investigate the enantioselective metabolic profile of the bone marrow (BM) and peripheral blood (PB) plasma samples from patients with acute myeloid leukemia (AML) at diagnosis and following completion of the induction phase of chemotherapeutic treatment. The sensitivity and selectivity of the developed method enabled the detection of trace levels of the D-enantiomer of HAs and AAs in primary plasma patient samples. Several of these metabolites were significantly altered in response to chemotherapy. The developed LC-HR-MS method entails a valuable step forward in chiral metabolomics.

Automated Trimethyl Sulfonium Hydroxide Derivatization Method for High-Throughput Fatty Acid Profiling by Gas Chromatography-Mass Spectrometry.

Fatty acid profiling on gas chromatography-mass spectrometry (GC-MS) platforms is typically performed offline by manually derivatizing and analyzing small batches of samples. A GC-MS system with a fully integrated robotic autosampler can significantly improve sample handling, standardize data collection, and reduce the total hands-on time required for sample analysis. In this study, we report an optimized high-throughput GC-MS-based methodology that utilizes trimethyl sulfonium hydroxide (TMSH) as a derivatization reagent to convert fatty acids into fatty acid methyl esters. An automated online derivatization method was developed, in which the robotic autosampler derivatizes each sample individually and injects it into the GC-MS system in a high-throughput manner. This study investigated the robustness of automated TMSH derivatization by comparing fatty acid standards and lipid extracts, derivatized manually in batches and online automatically from four biological matrices. Automated derivatization improved reproducibility in 19 of 33 fatty acid standards, with nearly half of the 33 confirmed fatty acids in biological samples demonstrating improved reproducibility when compared to manually derivatized samples. In summary, we show that the online TMSH-based derivatization methodology is ideal for high-throughput fatty acid analysis, allowing rapid and efficient fatty acid profiling, with reduced sample handling, faster data acquisition, and, ultimately, improved data reproducibility.

Stable Isotope Dilution LC-HRMS Assay To Determine Free SN-38, Total SN-38, and SN-38G in a Tumor Xenograft Model after Intravenous Administration of Antibody-Drug Conjugate (Sacituzumab Govitecan).

Antibody-drug conjugates (ADCs) have gained significant interest over the past few years due to their targeted delivery, higher efficacy, decreased toxicity and improved therapeutic index over conventional anticancer therapies. Sacituzumab govitecan (SG) is an ADC composed of a Trop-2-targeted antibody conjugated to the cytotoxic payload SN-38. SG is currently being evaluated in clinical trials of several solid cancers. In this nonclinical study, we have developed a highly sensitive and selective approach to measure free and total SN-38 and its glucuronidation metabolite (SN-38G) using stable isotope dilution (SID) ultrahigh-performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS). An efficient and fast hydrolysis procedure (2 h at 100 °C) was established to release SN-38, conjugated to the antibody by carbonate linkage. The assay involves the extraction of free SN-38, SN-38G by protein precipitation, and subsequent acid hydrolysis of the protein layer to release antibody-bound SN-38. The developed UHPLC-HRMS method resulted in good linearity (r2 ≥ 0.997), accuracy (RE ≤ ± 9.1%), precision (CVs ≤ 7.7%), and extraction recoveries (85.6-109.3%). The validated method was applied in the plasma and tumor of mice bearing human brain (U251) and breast (MDA-MB-468) tumor xenografts treated with a single dose (0.5 mg) of SG for 6 h. Results revealed the presence of trace level of SN-38G and free SN-38 in plasma, which suggests an improved therapeutic index of SG. The established method makes a significant contribution to the assessment of SG in different cancers.

Identification of a synergistic combination of dimethylaminoparthenolide and shikonin alters metabolism and inhibits proliferation of pediatric precursor-B cell acute lymphoblastic leukemia.

Exploiting metabolic vulnerabilities of cancer cells with nontoxic, plant derived compounds constitutes a novel strategy for both chemoprevention and treatment. A high-throughput screening approach was used to evaluate a library of natural products to determine the most synergistic combination in precursor-B cell acute lymphoblast leukemia. Dimethylaminoparthenolide and shikonin effectively inhibited proliferation resulting in cell death in primary and immortalized leukemia cells, while having negligible effects on normal cells. Dimethylaminoparthenolide and shikonin have been shown separately to inhibit cell survival and proliferative signaling and activate tumor suppressors and proapoptotic pathways. Untargeted metabolomics and metabolic flux analysis with stable isotopically labeled glucose and glutamine exhibited a global shift in metabolism following treatment. Pathway analysis indicated significant differences in amino acid, antioxidant, tricarboxylic acid cycle, and nucleotide metabolism. Together, dimethylaminoparthenolide and shikonin reduced the shunting of glycolytic intermediates into the pentose phosphate pathway for biosynthetic purposes. Similarly, the incorporation of glutamine and glutamine-derived metabolites into purine and pyrimidine synthesis was inhibited by the combination of dimethylaminoparthenolide and shikonin, effectively impeding biosynthetic pathways critical for leukemia cell survival. This approach demonstrates that a synergistic pair of compounds with malignant cell specificity can effectively target metabolic pathways crucial to leukemia cell proliferation and induce apoptosis.

Deletion of the neural tube defect-associated gene Mthfd1l disrupts one-carbon and central energy metabolism in mouse embryos.

One-carbon (1C) metabolism is a universal folate-dependent pathway essential for de novo purine and thymidylate synthesis, amino acid interconversion, universal methyl-donor production, and regeneration of redox cofactors. Homozygous deletion of the 1C pathway gene Mthfd1l encoding methylenetetrahydrofolate dehydrogenase (NADP+-dependent) 1-like, which catalyzes mitochondrial formate production from 10-formyltetrahydrofolate, results in 100% penetrant embryonic neural tube defects (NTDs), underscoring the central role of mitochondrially derived formate in embryonic development and providing a mechanistic link between folate and NTDs. However, the specific metabolic processes that are perturbed by Mthfd1l deletion are not known. Here, we performed untargeted metabolomics on whole Mthfd1l-null and wildtype mouse embryos in combination with isotope tracer analysis in mouse embryonic fibroblast (MEF) cell lines to identify Mthfd1l deletion-induced disruptions in 1C metabolism, glycolysis, and the TCA cycle. We found that maternal formate supplementation largely corrects these disruptions in Mthfd1l-null embryos. Serine tracer experiments revealed that Mthfd1l-null MEFs have altered methionine synthesis, indicating that Mthfd1l deletion impairs the methyl cycle. Supplementation of Mthfd1l-null MEFs with formate, hypoxanthine, or combined hypoxanthine and thymidine restored their growth to wildtype levels. Thymidine addition alone was ineffective, suggesting a purine synthesis defect in Mthfd1l-null MEFs. Tracer experiments also revealed lower proportions of labeled hypoxanthine and inosine monophosphate in Mthfd1l-null than in wildtype MEFs, suggesting that Mthfd1l deletion results in increased reliance on the purine salvage pathway. These results indicate that disruptions of mitochondrial 1C metabolism have wide-ranging consequences for many metabolic processes, including those that may not directly interact with 1C metabolism.

Metabolomic signature of brain cancer.

Despite advances in surgery and adjuvant therapy, brain tumors represent one of the leading causes of cancer-related mortality and morbidity in both adults and children. Gliomas constitute about 60% of all cerebral tumors, showing varying degrees of malignancy. They are difficult to treat due to dismal prognosis and limited therapeutics. Metabolomics is the untargeted and targeted analyses of endogenous and exogenous small molecules, which charact erizes the phenotype of an individual. This emerging "omics" science provides functional readouts of cellular activity that contribute greatly to the understanding of cancer biology including brain tumor biology. Metabolites are highly informative as a direct signature of biochemical activity; therefore, metabolite profiling has become a promising approach for clinical diagnostics and prognostics. The metabolic alterations are well-recognized as one of the key hallmarks in monitoring disease progression, therapy, and revealing new molecular targets for effective therapeutic intervention. Taking advantage of the latest high-throughput analytical technologies, that is, nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS), metabolomics is now a promising field for precision medicine and drug discovery. In the present report, we review the application of metabolomics and in vivo metabolic profiling in the context of adult gliomas and paediatric brain tumors. Analytical platforms such as high-resolution (HR) NMR, in vivo magnetic resonance spectroscopic imaging and high- and low-resolution MS are discussed. Moreover, the relevance of metabolic studies in the development of new therapeutic strategies for treatment of gliomas are reviewed.

Sociocultural Considerations in Juvenile Arthritis: A Review.

PROBLEM: Juvenile Arthritis (JA) is one of the most common autoimmune diseases in children. A variety of sociocultural factors that influence health outcomes in children with JA have been examined in previous research. However, clinical guidelines to guide the care of these children lack support because this research has not been systematically examined and synthesized. ELIGIBILITY CRITERIA: Primary research articles from five internet databases were included if they were peer-reviewed articles in English of studies conducted in the U.S. or Canada and referenced one or more determinants of health, quality of life, socioeconomic status, or health disparities in children with JA. SAMPLE: The final sample included 16 articles representing 2139 children and 939 parents. RESULTS: Topics covered in the studies included medication compliance, electronic medical records, environmental risk factors, economic hardship, parental coping, leisure activities, and their effects on patient outcomes including disability and quality of life. Patients with Medicaid experienced more severe outcomes than patients with private insurance despite equivalent levels of healthcare utilization. Other important topics, such as effects of the physical environment and alcohol use, were missing from the literature. CONCLUSIONS: Five categories of health determinants were found to influence outcomes: biology, individual behaviors, social environment, physical environment, and health services. Disparities continue to exist for racial and ethnic minority children with JA and those of low socioeconomic status. IMPLICATIONS: Sociocultural factors should be taken into consideration when developing care plans, research studies, and policies in order to remove barriers and promote the best outcomes for this vulnerable population.

Metabolomic Analysis of Diapausing and Noni-diapausing Larvae of the European Corn Borer Ostrinia nubilalis (Hbn.) (Lepidoptera: Crambidae).

In this study, an (1)H-NMR -based metabolomic approach was used to investigate the biochemical mechanisms of diapause and cold hardiness in diapausing larvae of the European corn borer Ostrinia nubilalis. Metabolomic patterns in polar hemolymph extracts from non-diapausing and diapausing larvae of O. nubilalis were compared. Analysis indicated 13 metabolites: 7 amino acids, glycerol, acetate, citrate, succinate, lactate and putrescine. Results show that diapausing larvae display different metabolomic patterns compared to active non-diapausing larvae, with predominant metabolites identified as glycerol, proline and alanine. In specific diapausing larvae initially kept at 5 °C then gradually chilled to ­3 °C and ­16 °C, alanine , glycerol and acetate were predominant metabolites. (1)H-NMR spectroscopy provides new insight into the metabolomic patterns associated with cold resistance and diapause in O. nubilalis larvae, suggesting distinct metabolomes function in actively developing and diapausing larvae.

Exploration of the intracellular chiral metabolome in pediatric BCP-ALL: a pilot study investigating the metabolic phenotype of IgH locus aberrations.

Background and aims: Aberrations in the immunoglobulin heavy chain (IgH) locus are associated with poor prognosis in pediatric precursor B-cell acute lymphoblastic leukemia (BCP-ALL) patients. The primary objective of this pilot study is to enhance our understanding of the IgH phenotype by exploring the intracellular chiral metabolome. Materials and methods: Leukemia cells were isolated from the bone marrow of BCP-ALL pediatric patients at diagnosis. The samples' metabolome and transcriptome were characterized using untargeted chiral metabolomic and next-generation sequencing transcriptomic analyses. Results: For the first time D- amino acids were identified in the leukemic cells' intracellular metabolome from the bone marrow niche. Chiral metabolic signatures at diagnosis was indicative of a resistant phenotype. Through integrated network analysis and Pearson correlation, confirmation was obtained regarding the association of the IgH phenotype with several genes linked to poor prognosis. Conclusion: The findings of this study have contributed to the understanding that the chiral metabolome plays a role in the poor prognosis observed in an exceptionally rare patient cohort. The findings include elevated D-amino acid incorporation in the IgH group, the emergence of several unknown, potentially enantiomeric, metabolites, and insights into metabolic pathways that all warrant further exploration.

SLC25A51 decouples the mitochondrial NAD+/NADH ratio to control proliferation of AML cells.

SLC25A51 selectively imports oxidized NAD+ into the mitochondrial matrix and is required for sustaining cell respiration. We observed elevated expression of SLC25A51 that correlated with poorer outcomes in patients with acute myeloid leukemia (AML), and we sought to determine the role SLC25A51 may serve in this disease. We found that lowering SLC25A51 levels led to increased apoptosis and prolonged survival in orthotopic xenograft models. Metabolic flux analyses indicated that depletion of SLC25A51 shunted flux away from mitochondrial oxidative pathways, notably without increased glycolytic flux. Depletion of SLC25A51 combined with 5-azacytidine treatment limits expansion of AML cells in vivo. Together, the data indicate that AML cells upregulate SLC25A51 to decouple mitochondrial NAD+/NADH for a proliferative advantage by supporting oxidative reactions from a variety of fuels. Thus, SLC25A51 represents a critical regulator that can be exploited by cancer cells and may be a vulnerability for refractory AML.

Human mitochondrial uncoupling protein 3 functions as a metabolite transporter.

Since its discovery, a major debate about mitochondrial uncoupling protein 3 (UCP3) has been whether its metabolic actions result primarily from mitochondrial inner membrane proton transport, a process that decreases respiratory efficiency and ATP synthesis. However, UCP3 expression and activity are induced by conditions that would seem at odds with inefficient 'uncoupled' respiration, including fasting and exercise. Here, we demonstrate that the bacterially expressed human UCP3, reconstituted into liposomes, catalyses a strict exchange of aspartate, malate, sulphate and phosphate. The R282Q mutation abolishes the transport activity of the protein. Although the substrate specificity and inhibitor sensitivity of UCP3 display similarity with that of its close homolog UCP2, the two proteins significantly differ in their transport mode and kinetic constants.

Phase 1 clinical trial evaluating safety, bioavailability, and gut microbiome with a combination of curcumin and ursolic acid in lipid enhanced capsules.

As screening strategies employ better biomarkers and genetics to identify individuals at an increased risk of prostate cancer, there are currently no chemotherapeutic prevention strategies. With any chemoprevention strategy, the population will be younger and healthier; therefore, they will be less tolerant of side effects. This study translated findings from screening a natural product library and pre-clinical evaluation of curcumin (CURC) in combination with ursolic acid (UA) in prostate cancer models. After manufacturing capsules for each compound, 18 subjects were enrolled. The study used a 3 × 3 phase 1 clinical trial to evaluate CURC (1200 mg/day) and UA (300 mg/day) alone and in combination over a 2-week period with endpoints of safety, bioavailability, and microbiome alterations. After enrolling six subjects in each arm, we found no grade 3 or 4 events and only minor changes in the safety laboratory values. In the pooled analysis of groups, we noted a statistically significant difference between median serum levels of UA when administered alone vs administered in the combination (2.7 ng/mL vs 43.8 ng/mL, p = 0.03). Individuals receiving the combination also had a favorable impact on gut microbiome status and a reduction in "microbiome score" predictive of prostate cancer risk.

Sacituzumab Govitecan in patients with breast cancer brain metastases and recurrent glioblastoma: a phase 0 window-of-opportunity trial.

Sacituzumab Govitecan (SG) is an antibody-drug conjugate that has demonstrated efficacy in patients with TROP-2 expressing epithelial cancers. In a xenograft model of intracranial breast cancer, SG inhibited tumor growth and increased mouse survival. We conducted a prospective window-of-opportunity trial (NCT03995706) at the University of Texas Health Science Center at San Antonio to examine the intra-tumoral concentrations and intracranial activity of SG in patients undergoing craniotomy for breast cancer with brain metastases (BCBM) or recurrent glioblastoma (rGBM). We enrolled 25 patients aged ≥18 years diagnosed with BCBM and rGBM to receive a single intravenous dose of SG at 10 mg/kg given one day before resection and continued on days 1 and 8 of 21-day cycles following recovery. The PFS was 8 months and 2 months for BCBM and rGBM cohorts, respectively. The OS was 35.2 months and 9.5 months, respectively. Grade≥3 AE included neutropenia (28%), hypokalemia (8%), seizure (8%), thromboembolic event (8%), urinary tract infection (8%) and muscle weakness of the lower limb (8%). In post-surgical tissue, the median total SN-38 was 249.8 ng/g for BCBM and 104.5 ng/g for rGBM, thus fulfilling the primary endpoint. Biomarker analysis suggests delivery of payload by direct release at target site and that hypoxic changes do not drive indirect release. Secondary endpoint of OS was 35.2 months for the BCBM cohort and 9.5 months for rGBM. Non-planned exploratory endpoint of ORR was 38% for BCBM and 29%, respectively. Exploratory endpoint of Trop-2 expression was observed in 100% of BCBM and 78% of rGBM tumors. In conclusion, SG was found to be well tolerated with adequate penetration into intracranial tumors and promising preliminary activity within the CNS. Trial Registration: Trial (NCT03995706) enrolled at Clinical Trials.gov as Neuro/Sacituzumab Govitecan/Breast Brain Metastasis/Glioblastoma/Ph 0: https://clinicaltrials.gov/study/NCT03995706?cond=NCT03995706 .