Physiologically Based Pharmacokinetic Modeling Approach to Predict Drug-Drug Interactions With Ethionamide Involving Impact of Genetic Polymorphism on FMO3.

J Clin Pharmacol. 2019 06;59(6):880-889

Authors: Nguyen PTT, Parvez MM, Kim MJ, Yoo SE, Ahn S, Ghim JL, Shin JG

Abstract
The widely used second-line antituberculosis drug ethionamide shows wide interindividual variability in its disposition; however, the relevant factors affecting this phenomenon have not been characterized. We previously reported the major contribution of flavin-containing monooxygenase 3 (FMO3) in the reductive elimination pathway of ethionamide. In this study, ethionamide metabolism was potentially inhibited by methimazole in vitro. The drug-drug interaction leading to methimazole affecting the disposition of ethionamide mediated by FMO3 was then quantitated using a bottom-up approach with a physiologically based pharmacokinetic framework. The maximum concentration (Cmax ) and area under the curve (AUC) of ethionamide were estimated to increase by 13% and 16%, respectively, when coadministered with methimazole. Subsequently, we explored the effect of FMO3 genetic polymorphism on metabolic capacity, by constructing 2 common functional variants, Lys158 -FMO3 and Gly308 -FMO3. Compared to the wild type, recombinant Lys158 -FMO3 and Gly308 -FMO3 variants significantly decreased the intrinsic clearance of ethionamide by 2% and 24%, respectively. Two prevalent functional variants of FMO3 were predicted to affect ethionamide disposition, with mean ratios of Cmax and AUC of up to 1.5 and 1.7, respectively, in comparison with the wild type. In comparing single ethionamide administration with the wild type, simulations of the combined effects of comedications and FMO3 genetic polymorphism estimated that the Cmax and AUC ratios of ethionamide increased up to 1.7 and 2.0, respectively. These findings suggested that FMO3-mediated drug-drug interaction and genetic polymorphism could be important determinants of interindividual heterogeneity in ethionamide disposition that need to be considered comprehensively to optimize the personalized dosing of ethionamide.

PMID: 30690726 [PubMed - indexed for MEDLINE]

Dynamic Regulation of SARS-Cov-2 Binding and Cell Entry Mechanisms in Remodeled Human Ventricular Myocardium.

JACC Basic Transl Sci. 2020 Jun 24;:

Authors: Bristow MR, Zisman LS, Altman NL, Gilbert EM, Lowes BD, Minobe WA, Slavov D, Schwisow JA, Rodriguez EM, Carroll IA, Keuer TA, Buttrick PM, Kao DP

Abstract
Using serial analysis of myocardial gene expression employing endomyocardial biopsy starting material in a dilated cardiomyopathy cohort, we show that mRNA expression of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) cardiac myocyte receptor ACE2 is up-regulated with remodeling and with reverse remodeling down-regulates into the normal range. The proteases responsible for virus-cell membrane fusion were expressed but not regulated with remodeling. In addition, a new candidate for severe acute respiratory syndrome coronavirus 2 cell binding and entry was identified, the integrin encoded by ITGA5. Up-regulation in ACE2 in remodeled left ventricles may explain worse outcomes in patients with coronavirus disease 2019 who have underlying myocardial disorders, and counteracting ACE2 up-regulation is a possible therapeutic approach to minimizing cardiac damage.

PMID: 32838074 [PubMed - as supplied by publisher]

A history of the roles of cytochrome P450 enzymes in the toxicity of drugs.

Toxicol Res. 2020 Aug 18;:1-23

Authors: Guengerich FP

Abstract
The history of drug metabolism began in the 19th Century and developed slowly. In the mid-20th Century the relationship between drug metabolism and toxicity became appreciated, and the roles of cytochrome P450 (P450) enzymes began to be defined in the 1960s. Today we understand much about the metabolism of drugs and many aspects of safety assessment in the context of a relatively small number of human P450s. P450s affect drug toxicity mainly by either reducing exposure to the parent molecule or, in some cases, by converting the drug into a toxic entity. Some of the factors involved are enzyme induction, enzyme inhibition (both reversible and irreversible), and pharmacogenetics. Issues related to drug toxicity include drug-drug interactions, drug-food interactions, and the roles of chemical moieties of drug candidates in drug discovery and development. The maturation of the field of P450 and drug toxicity has been facilitated by advances in analytical chemistry, computational capability, biochemistry and enzymology, and molecular and cell biology. Problems still arise with P450s and drug toxicity in drug discovery and development, and in the pharmaceutical industry the interaction of scientists in medicinal chemistry, drug metabolism, and safety assessment is critical for success.

PMID: 32837681 [PubMed - as supplied by publisher]

One-pot fabrication of dual-emission and single-emission biomass carbon dots for Cu2+ and tetracycline sensing and multicolor cellular imaging.

Anal Bioanal Chem. 2020 Aug 24;:

Authors: Wu L, Long R, Li T, Tang C, Tong X, Guo Y, Shi S, Xiang H, Tong C

Abstract
Dual-emission and single-emission carbon dots (DCDs and SCDs) have been simultaneously synthesized by one-pot solvothermal treatment of leek. Different graphitization and surface functionalization were responsible for their distinction in fluorescence characteristics. DCDs with an average size of 5.6 nm exhibited two emissions at 489 and 676 nm under 420-nm excitation. Complexation between DCDs' surface porphyrins and Cu2+ led to quenching of the 676-nm emission, which resulted in the ratiometric determination of Cu2+ with a limit of detection (LOD) of 0.085 μM. SCDs, containing additional sulfur element (0.50%) with an average size of 7.7 nm, presented a single emission at 440 nm under 365-nm excitation. The static quenching and inner filter effects between SCDs and tetracyclines (TCs) made SCDs a fluorescence nanoprobe for TCs' determination with LODs of 0.26-0.48 μM. Applications of DCDs and SCDs for respective determination of Cu2+ and TCs in milk and pig liver samples were successfully demonstrated. Moreover, good photostability, low toxicity, and outstanding biocompatibility made DCDs and SCDs suitable for multicolor cellular imaging. Results indicate that natural products are excellent raw materials to controllably synthesize CDs with prominent physicochemical and fluorescence properties.Graphical abstract.

PMID: 32833074 [PubMed - as supplied by publisher]

A new coumarin compound DCH combats methicillin-resistant Staphylococcus aureus biofilm by targeting arginine repressor.

Sci Adv. 2020 Jul;6(30):eaay9597

Authors: Qu D, Hou Z, Li J, Luo L, Su S, Ye Z, Bai Y, Zhang X, Chen G, Li Z, Wang Y, Xue X, Luo X, Li M

Abstract
Staphylococcus aureus infection is difficult to eradicate because of biofilm formation and antibiotic resistance. The increasing prevalence of methicillin-resistant Staphylococcus aureus (MRSA) infection necessitates the development of a new agent against bacterial biofilms. We report a new coumarin compound, termed DCH, that effectively combats MRSA in vitro and in vivo and exhibits potent antibiofilm activity without detectable resistance. Cellular proteome analysis suggests that the molecular mechanism of action of DCH involves the arginine catabolic pathway. Using molecular docking and binding affinity assays of DCH, and comparison of the properties of wild-type and ArgR-deficient MRSA strains, we demonstrate that the arginine repressor ArgR, an essential regulator of the arginine catabolic pathway, is the target of DCH. These findings indicate that DCH is a promising lead compound and validate bacterial ArgR as a potential target in the development of new drugs against MRSA biofilms.

PMID: 32832655 [PubMed - as supplied by publisher]

Why are there Variations in the Responses of Glucagon-like Peptide-1 Agonists among the Type 2 Diabetic Patients?

Curr Clin Pharmacol. 2019;14(3):247-248

Authors: Ajith TA

PMID: 31971106 [PubMed - indexed for MEDLINE]

Efavirenz Pharmacogenetics and Weight Gain following Switch to Integrase Inhibitor-containing Regimens.

Clin Infect Dis. 2020 Aug 23;:

Authors: Leonard MA, Cindi Z, Bradford Y, Bourgi K, Koethe J, Turner M, Norwood J, Woodward B, Erdem H, Basham R, Baker P, Rebeiro PF, Sterling TR, Hulgan T, Daar ES, Gulick R, Riddler SA, Sinxadi P, Ritchie MD, Haas DW

Abstract
BACKGROUND: Unwanted weight gain affects some people living with HIV who are prescribed integrase strand transfer inhibitors (INSTI). Mechanisms and risk factors are incompletely understood.
METHODS: We utilized two cohorts to study pharmacogenetics of weight gain following switch from efavirenz- to INSTI-based regimens. In an observational cohort, we studied weight gain at 48 weeks following switch from efavirenz- to INSTI-based regimens among patients who had been virologically suppressed for at least 2 years at a clinic in the United States. Associations were characterized with CYP2B6 and UGT1A1 genotypes that affect efavirenz and INSTI metabolism, respectively. In a clinical trials cohort, we studied weight gain at 48 weeks among treatment-naïve participants who were randomized to receive efavirenz-containing regimens in AIDS Clinical Trials Group studies A5095, A5142 and A5202 and did not receive INSTIs.
RESULTS: In the observational cohort (N=61), CYP2B6 slow metabolizers had greater weight gain after switch (p=0.01). This was seen following switch to elvitegravir or raltegravir, but not dolutegravir. UGT1A1 genotype was not associated with weight gain. In the clinical trials cohort (N=462), CYP2B6 slow metabolizers had lesser weight gain at week 48 among participants receiving efavirenz with tenofovir disoproxil fumarate (p=0.001) but not those receiving efavirenz with abacavir (p=0.65). Findings were consistent when stratified by race/ethnicity and by sex.
CONCLUSIONS: Among patients who switched from efavirenz- to INSTI-based therapy, CYP2B6 genotype was associated with weight gain, possibly reflecting withdrawal of the inhibitory effect of higher efavirenz concentrations on weight gain. The difference by concomitant nucleoside analogue is unexplained.

PMID: 32829410 [PubMed - as supplied by publisher]

Host Polymorphisms May Impact SARS-CoV-2 Infectivity.

Trends Genet. 2020 Aug 10;:

Authors: Brest P, Refae S, Mograbi B, Hofman P, Milano G

Abstract
Based on a broad public database compilation, we support the hypothesis that germinal polymorphisms may regulate the expression of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cellular target itself and proteases controlling the process of its shedding or, conversely, its internalization. Consequently, a genetic influence on individual susceptibility to coronavirus disease 2019 (COVID-19) infection is strongly suspected.

PMID: 32828550 [PubMed - as supplied by publisher]

11 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results:

pharmacogenomics

These pubmed results were generated on 2020/08/23

PubMed comprises more than millions of citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

Integrated Analysis of DNA Methylation, Hydroxymethylation, and Gene Expression Data Using ME-Class2.

Methods Mol Biol. 2021;2198:467-489

Authors: Singh MK, Edwards JR

Abstract
There is increasing interest in understanding the pathological role of DNA methylation changes in disease by profiling genome-wide methylation changes. This includes both 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC). The typical profiling study is designed to measure 5mC and/or 5hmC levels alongside gene expression in a set of samples and controls to determine a list of candidate genes whose 5mC and/or 5hmC changes are associated with expression changes. We recently showed that ME-Class2 substantially outperforms other bioinformatic approaches at accurately identify genes with highly associated methylation and expression changes. ME-Class2 further illuminated how synergistic changes in 5mC and 5hmC potentially contribute to gene silencing and activation. Here we present a detailed protocol for using ME-Class2 to analyze genome-wide methylation (5mC and/or 5hmC) and expression data. Further, we provide advice about extending ME-Class2 to study the relationships between other epigenetic marks.

PMID: 32822051 [PubMed - as supplied by publisher]

Application of pharmacogenetics in oncology.

Biomark Res. 2020;8:32

Authors: Miteva-Marcheva NN, Ivanov HY, Dimitrov DK, Stoyanova VK

Abstract
The term "pharmacogenetics" is used to describe the study of variability in drug response due to heredity. It is associated with "gene - drug interactions". Later on, the term "pharmacogenomics" has been introduced and it comprises all genes in the genome that can define drug response. The application of pharmacogenetics in oncology is of a great significance because of the narrow therapeutic index of chemotherapeutic drugs and the risk for life-threatening adverse effects. Many cancer genomics studies have been focused on the acquired, somatic mutations; however, increasing evidence shows that inherited germline genetic variations play a key role in cancer risk and treatment outcome. The aim of this review is to summarize the state of pharmacogenomics in oncology, focusing only on germline mutations. Genetic polymorphisms can be found in the genes that code for the metabolic enzymes and cellular targets for most of the chemotherapy drugs. Nevertheless, predicting treatment outcome is still not possible for the majority of regimens. In this review, we discuss the most comprehensively studied drug-gene pairs - present knowledge and current limitations. However, further studies in larger groups of cancer patients are necessary to be conducted with precise validation of pharmacogenetic biomarkers before these markers could be routinely applied in clinical diagnosis and treatment.

PMID: 32821392 [PubMed - as supplied by publisher]

Clinical Utility of CYP2C19 Genotype-Guided Antiplatelet Therapy in Patients at Risk of Adverse Cardiovascular and Cerebrovascular Events: A Review of Emerging Evidence.

Pharmgenomics Pers Med. 2020;13:239-252

Authors: Gower MN, Ratner LR, Williams AK, Rossi JS, Stouffer GA, Lee CR

Abstract
In patients undergoing percutaneous coronary intervention (PCI), the standard of care is dual antiplatelet therapy with a P2Y12 inhibitor (clopidogrel, prasugrel, or ticagrelor) and aspirin. Current clinical practice guidelines now recommend more potent P2Y12 inhibitors (prasugrel or ticagrelor) over clopidogrel in acute coronary syndrome (ACS). However, clopidogrel remains the most commonly prescribed P2Y12 inhibitor in the setting of PCI and is also the preferred agent in the treatment and secondary prevention of stroke. Clopidogrel is a prodrug that requires bioactivation by the CYP2C19 enzyme. It has been shown that clopidogrel use in patients who are CYP2C19 no function allele carriers are associated with impaired antiplatelet inhibition and a higher risk of major adverse cardiovascular and cerebrovascular events. Compared to clopidogrel, prasugrel and ticagrelor clinical response is not impacted by CYP2C19 genotype. Even with a demonstrated increased risk of adverse outcomes in CYP2C19 no function allele carriers treated with clopidogrel, routine implementation of CYP2C19 genotyping to guide antiplatelet therapy selection has remained controversial and has not been widely adopted. Recent results from multiple prospective randomized and nonrandomized clinical trials investigating the use of CYP2C19 genotype-guided antiplatelet therapy following PCI have advanced the evidence base demonstrating the clinical utility of this strategy. Multiple recent studies have examined the effects of CYP2C19 genotype on clopidogrel outcomes in the setting of stroke and neurointerventional procedures. In this review, we discern the clinical utility of using CYP2C19 genotype testing to guide antiplatelet therapy prescribing by evaluating the impact of CYP2C19 genotype-guided selection of antiplatelet therapy on clinical outcomes, summarizing emerging data from cardiovascular and neurology clinical studies, and discussing implications for clinical practice guidelines, remaining knowledge gaps and future research directions.

PMID: 32821149 [PubMed - as supplied by publisher]

Lack of genetic evidence that fatty liver disease predisposes to COVID-19.

J Hepatol. 2020 09;73(3):709-711

Authors: Valenti L, Jamialahmadi O, Romeo S

PMID: 32445883 [PubMed - indexed for MEDLINE]

Initial dose recommendation for sirolimus in paediatric kaposiform haemangioendothelioma patients based on population pharmacokinetics and pharmacogenomics.

J Int Med Res. 2020 Aug;48(8):300060520947627

Authors: Chen X, Wang DD, Xu H, Li ZP

Abstract
OBJECTIVE: Sirolimus has been used to treat paediatric kaposiform haemangioendothelioma patients. However, there is considerable pharmacokinetic variability among individuals, and it is difficult to develop an initial dosing regimen. The goal of the present study is to recommend an initial sirolimus dose in paediatric kaposiform haemangioendothelioma patients based on population pharmacokinetics and pharmacogenomics.
METHODS: This was a retrospective clinical study. A population pharmacokinetics model was established and population characteristics, laboratory test results, drug combinations, and pharmacogenomics were considered as potential covariates. The Monte Carlo method was used to simulate the optimal initial dosage.
RESULTS: The final covariates that affect sirolimus clearance include weight and the CYP3A5 genotype. The initial dosage of sirolimus for individuals with CYP3A5*3/*3 was 0.20 mg/kg split into two doses for 5 to 60 kg body weight. For individuals with CYP3A5*1, the initial dose was 0.23 mg/kg split into two doses for 5 to 30 kg body weight and 0.20 mg/kg split into two doses for 30 to 60 kg body weight.
CONCLUSION: The recommendation for the initial sirolimus dose in paediatric kaposiform haemangioendothelioma patients was based on population pharmacokinetics and pharmacogenomics. This study may provide practical value for sirolimus clinical use in paediatric kaposiform haemangioendothelioma patients.

PMID: 32815764 [PubMed - as supplied by publisher]

Polymorphisms within the RANK and RANKL Encoding Genes in Patients with Rheumatoid Arthritis: Association with Disease Progression and Effectiveness of the Biological Treatment.

Arch Immunol Ther Exp (Warsz). 2020 Aug 19;68(4):24

Authors: Wielińska J, Kolossa K, Świerkot J, Dratwa M, Iwaszko M, Bugaj B, Wysoczańska B, Chaszczewska-Markowska M, Jeka S, Bogunia-Kubik K

Abstract
Inconsistency of the results regarding the genetic variability within genes coding for receptor activator of nuclear factor κB (RANK) and its ligand (RANKL) in rheumatoid arthritis (RA) prompted us to study the RANK and RANKL polymorphisms as potential biomarkers associated with disease predisposition and response to anti-TNF treatment in a group of Polish patients with RA. This study enrolled 318 RA patients and 163 controls. RANK (rs8086340, C > G; rs1805034, C > T) and RANKL (rs7325635, G > A; rs7988338 G > A) alleles were determined by real-time PCR with melting curve analysis and related with clinical parameters. In addition, RANKL serum levels were measured by ELISA. The RANK rs8086340-G allele was overrepresented among patients as compared to controls (OD = 1.777, p = 0.038). C-reactive protein (CRP) levels were significantly (p < 0.05) associated with RANK rs8086340 polymorphism and were higher in the CC-homozygotes at the baseline while lower in the GG-carriers at the 12th week of the treatment. At the latter time point RANKL rs7325635-GG-positive patients also showed significantly lower CRP concentrations. Higher alkaline phosphatase levels before induction of anti-TNF therapy were observed in RANK rs8086340 and RANK rs1805034 CC homozygotes (p = 0.057 and p = 0.035, respectively). The GG homozygosity of both RANKL single nucleotide polymorphisms was significantly associated with the number of swollen joints (rs7988338 and rs7325635, before and at the 12th week of therapy, respectively, p < 0.05 in both cases). These results imply that polymorphisms within the RANK and RANKL genes affect RA susceptibility and anti-TNF treatment outcome.

PMID: 32815001 [PubMed - in process]

Nurse empowerment through Pharmacogenetics.

Rev Lat Am Enfermagem. 2020;28:e3265

Authors: Moraes JC, Nunes FDD, Coeli-Lacchini FB, Miyazaki AHL, Flória-Santos M, Lacchini R

Abstract
OBJECTIVE: to verify the existence of elements that justify the use of pharmacogenetics by the Brazilian nurse.
METHOD: this is a quantitative, cross-sectional, observational, descriptive study, whose final sample was 67 individuals. The participants were healthy at the time of the study and reported a history of previous use and the occurrence of adverse effects by drugs commonly used and metabolized by CYP2C9. We collected 4 mL of venous blood for subsequent DNA extraction by salting out method and genotyping of the CYP2C9*2 and CYP2C9*3 polymorphisms, using Polymerase Chain Reaction in real time using Taqman assays.
RESULTS: the use of drugs metabolized by CYP2C9 was frequent (more than 75% of the individuals have already used between 2 or 4 of these drugs). Regarding adverse events, there were 19 perceived symptomatic occurrences associated with drugs metabolized by CYP2C9. The allele frequency of the polymorphism * 2 and * 3 in the population studied was 11.1% and 7.5%, respectively, and there was a coincidence between the presence of alleles of low enzyme activity and the occurrence of adverse effects.
CONCLUSION: there are elements that justify the adoption of pharmacogenetics in the nursing care to reduce the occurrence of adverse reactions to drugs metabolized by CYP2C9.

PMID: 32813781 [PubMed - as supplied by publisher]

Genomic Association Analysis Reveals Variants Associated With Blood Pressure Response to Beta-Blockers in European Americans.

Clin Transl Sci. 2019 09;12(5):497-504

Authors: Singh S, El Rouby N, McDonough CW, Gong Y, Bailey KR, Boerwinkle E, Chapman AB, Gums JG, Turner ST, Cooper-DeHoff RM, Johnson JA

Abstract
European Americans (EA) have a better antihypertensive response to β-blockers when compared with African Americans, albeit with some variability. We undertook a genomewide association study to elucidate the underlying genetic determinants in EA contributing to this variability in blood pressure (BP) response. A discovery genomewide association study of change in BP post-metoprolol treatment was performed in EA participants (n = 201) from the Pharmacogenomic Evaluation of Antihypertensive Responses-2 (PEAR-2) study and tested for replication in the atenolol-treated EA from the PEAR study (n = 233). Rs294610 in the FGD5, which encodes for FYVE, RhoGEF and PH Domain Containing 5, (expression quantitative trait loci for FGD5 in the small intestine) was significantly associated with increased diastolic BP response to β-blockers in the PEAR-2 study (P = 3.41 × 10-6 , β = -2.70) and replicated (P = 0.01, β = -1.17) in the PEAR study. Post-meta-analysis of these studies, an additional single nucleotide polymorphism rs45545233 in the SLC4A1, encoding for Solute Carrier Family 4 Member 1, (expression quantitative trait loci for dual specificity phosphatase 3 in the artery tibial) was identified that was significantly associated with a poor response to β-blockers (P = 3.43 × 10-6 , β = 4.57) and was replicated in the atenolol add-on cohort (P = 0.007, β = 4.97). We identified variants in FGD5 and SLC4A1, which have been previously cited as candidate genes for hypertension, to be associated with a β-blocker BP response in EA. Further elucidation is warranted of the underlying mechanisms of these variants and genes by which they influence the BP response to β-blockers.

PMID: 31033190 [PubMed - indexed for MEDLINE]

A population approach of rifampicin pharmacogenetics and pharmacokinetics in Mexican patients with tuberculosis.

Tuberculosis (Edinb). 2020 Aug 08;124:101982

Authors: Medellin-Garibay SE, Huerta-García AP, Rodríguez-Báez AS, Magaña-Aquino M, Ortiz-Álvarez A, Portales-Pérez DP, Milán-Segovia RDC, Romano-Moreno S

Abstract
The aim of this study was to develop a population pharmacokinetic model of rifampicin (RMP) in Mexican patients with tuberculosis (TB) to evaluate the influence of anthropometric and clinical covariates, as well as genotypic variants associated with MDR1 and OATP1B1 transporters. A prospective study approved by Research Ethics Committee was performed at Hospital Central in San Luis Potosí, Mexico. TB patients under DOTS scheme and who signed informed consent were consecutively included. Anthropometric and clinical information was retrieved from medical records. Single nucleotide polymorphisms in MDR1 (C3435T) and SLCO1B1 (A388G and T521C) genes were evaluated. RMP plasma concentrations and time data were assessed with NONMEM software. A total of 71 Mexican TB patients from 18 to 72 years old were included for RMP quantification from 0.3 to 12 h after dose; 329 and 97 plasma concentrations were available for model development and validation, respectively. Sequential process includes a typical lag time of 0.25 h prior to absorption start with a Ka of 1.24 h-1 and a zero-order absorption of 0.62 h to characterize the gradual increase in RMP plasma concentrations. Final model includes total body weight in volume of distribution (0.7 L/kg, CV = 26.8%) and a total clearance of 5.96 L/h (CV = 38.5%). Bioavailability was modified according to time under treatment and generic formulation administration. In conclusion, a population pharmacokinetic model was developed to describe the variability in RMP plasma concentrations in Mexican TB patients. Genetic variants evaluated did not showed significant influence on pharmacokinetic parameters. Final model will allow therapeutic drug monitoring at early stages.

PMID: 32810723 [PubMed - as supplied by publisher]

MYC-binding lncRNA EPIC1 promotes AKT-mTORC1 signaling and rapamycin resistance in breast and ovarian cancer.

Mol Carcinog. 2020 Aug 18;:

Authors: Wang Y, Zhang M, Wang Z, Guo W, Yang D

Abstract
AKT-mTORC1 (mammalian target of rapamycin complex 1) signaling pathway plays a critical role in tumorigenesis and can be targeted by rapamycin. However, the underlying mechanism of how long noncoding RNA (lncRNAs) regulate the AKT-mTORC1 pathway remains unclear. EPIC1 (epigenetically-induced lncRNA 1) is a Myc-binding lncRNA, which has been previously demonstrated to be overexpressed in multiple cancer types. In a pathway analysis including 4962 cancer patients, we observed that lncRNA EPIC1 expression was positively correlated with the AKT-mTORC1 signaling pathway in more than 10 cancer types, including breast and ovarian cancers. RNA-seq analysis of breast and ovarian cancer cells demonstrated that EPIC1-knockdown led to the downregulation of genes in the AKT-mTORC1 signaling pathway. In MCF-7, OVCAR4, and A2780cis cell lines, EPIC1 knockdown and overexpression, respectively, inhibited and activated phosphorylated AKT and the downstream phosphorylation levels of 4EBP1 and S6K. Further knockdown of Myc abolished the EPIC1's regulation of AKT-mTORC1 signaling; suggested that the regulation of phosphorylation level of AKT, 4EBP1, and S6K by EPIC1 depended on the expression of Myc. Moreover, EPIC1 overexpressed MCF-7, A2780cis, and OVCAR4 cells treated with rapamycin showed a significant decreasing in rapamycin mediated inhibition of p-S6K and p-S6 comparing with the control group. In addition, Colony Formation assay and MTT assay indicated that EPIC1 overexpression led to rapamycin resistance in breast and ovarian cancer cell lines. Our results demonstrated the lncRNA EPIC1 expression activated the AKT-mTORC1 signaling pathway through Myc and led to rapamycin resistance in breast and ovarian cancer.

PMID: 32810332 [PubMed - as supplied by publisher]

Obese-Inflammatory Phenotypes in Heart Failure With Preserved Ejection Fraction.

Circ Heart Fail. 2020 Aug;13(8):e006414

Authors: Sabbah MS, Fayyaz AU, de Denus S, Felker GM, Borlaug BA, Dasari S, Carter RE, Redfield MM

Abstract
BACKGROUND: Comorbidity-driven microvascular inflammation is posited as a unifying pathophysiologic mechanism for heart failure with preserved ejection fraction (HFpEF). Obesity is proinflammatory and common in HFpEF. We hypothesized that unique obesity-inflammation HFpEF phenotypes exist and are associated with differences in clinical features, fibrosis biomarkers, and functional performance.
METHODS: Patients (n=301) from 3 HFpEF clinical trials were studied. Unsupervised machine learning (hierarchical clustering) with obese status and 13 inflammatory biomarkers as input variables was performed. Associations of clusters with HFpEF severity and fibrosis biomarkers (PIIINP [procollagen III N-terminal peptide], CITP [C-telopeptide for type I collagen], IGFBP7 [insulin-like growth factor-binding protein-7], and GAL-3 [galectin-3]) were assessed.
RESULTS: Hierarchical clustering revealed 3 phenotypes: pan-inflammatory (n=129; 64% obese), noninflammatory (n=83; 55% obese), and obese high CRP (C-reactive protein; n=89; 98% obese). The pan-inflammatory phenotype had more comorbidities and heart failure hospitalizations; higher left atrial volume, NT-proBNP (N-terminal pro-B-type natriuretic peptide), and fibrosis biomarkers; and lower glomerular filtration rate, peak oxygen consumption, 6-minute walk distance, and active hours/day (P<0.05 for all). The noninflammatory phenotype had the most favorable values for all measures. The obese high CRP phenotype resembled the noninflammatory phenotype except for isolated elevation of CRP and lower functional performance. Hierarchical cluster assignment was independent of CRP genotype combinations that alter CRP levels and more biologically plausible than other clustering approaches. Multiple traditional analytic techniques confirmed and extended the hierarchical clustering findings.
CONCLUSIONS: Unique obesity-inflammation phenotypes exist in HFpEF and are associated with differences in comorbidity burden, HFpEF severity, and fibrosis. These data support comorbidity-driven microvascular inflammation as a pathophysiologic mechanism for many but not all HFpEF patients.

PMID: 32809874 [PubMed - as supplied by publisher]