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Radiation-guided nanoparticles enhance the efficacy of PARP inhibitors in primary and metastatic BRCA1-deficient tumors via immunotherapy.

Poly (ADP-ribose) polymerase inhibitors (PARPi) have revolutionized the treatment landscape for patients suffering from BRCA1-mutated breast and ovarian cancers. However, responses are not durable. We demonstrate that treatment with PARPi, niraparib, increases programmed death-ligand 1 (PD-L1) expression in BRCA1-deficient cancer cells, contributing to immune evasion. To circumvent this, we developed P-selectin-targeted poly (lactic-co-glycolic) acid (PLGA)-poly (ethylene glycol) (PEG)-based nanoparticles (NPs) encapsulating PARP and PD-L1 inhibitors at a synergistic ratio. To further enhance …

Targeting the Heart of Mycobacterium: Advances in Anti-Tubercular Agents Disrupting Cell Wall Biosynthesis.

Mycobacterium tuberculosis infections continue to pose a significant global health challenge, particularly due to the rise of multidrug-resi … id synthesis, with recent evidence indicating that delamanid also inhibits decaprenylphosphoryl-β-D-ribose-2-epimerase, thereby impairing arabinogalactan biosynthesis. Cycloserine remains the sole approved drug that inhibits peptidoglycan synthesis, the foundational layer of the mycobacterial cell wall. Furthermore, ethambutol interferes with arabinogala …

DprE1 inhibitors: An insight into the recent developments and synthetic approaches.

In the current medical era, the proliferation and dissemination of drug-resistant strains of Mycobacterium tuberculosis (Mtb) continue to pose a significant worldwide health hazard, necessitating the development of new and innovative medications to combat tuberculosis. Decaprenylphosphoryl-β-D-ribose 2'-epimerase (DprE1) is a crucial enzyme for cell wall synthesis in Mtb. Its importance is due to its eminent contribution in forming lipoarabinomannan and arabinogalactan, key components of the mycobacterial cell wall. The emergence of the DprE1 enzyme as a druggable target was based on inhibitor…

Потенциальные цели микроглии в лечении нейродегенеративных заболеваний: механизм и терапевтические последствия.

В случае различных нейродегенеративных расстройств активируются микроглиальные клетки. Кроме того, дисфункциональная и гиперактивированная микроглия инициирует митохондриальную автофагию, окислительный стресс и патологическое накопление белка, заканчивающееся нейроинфламмацией, которая усугубляет повреждения допаминергических нейронов и вносит значительный вклад в патологию нейродегенеративного расстройства. Микроглиальная чрезмерная активация тесно связана с секрецией провоспалительных цитокинов, фагоцитозом травмированных нейронов и модуляцией нейротоксичной среды. В этом обзоре резюмируется

Совпадение в аннотации оригинала
For diverse neurodegenerative disorders, microglial cells are activated. Furthermore, dysfunctional and hyperactivated microglia initiate mi … death such as ferroptosis, cuproptosis, disulfidptosis, and parthanatos (poly(adenosine diphosphate ribose) polymerase 1-dependent cell death), as well as the impact of regulatory factors related to microglial inflammation on microglial activation and neuroinflammation. The aim is to identify potential targets for microglial cell therapy in neurodegenera …

To modulate or to skip: De-escalating PARP inhibitor maintenance therapy in ovarian cancer using adaptive therapy.

Toxicity and emerging drug resistance pose important challenges in poly-adenosine ribose polymerase inhibitor (PARPi) maintenance therapy of ovarian cancer. We propose that adaptive therapy, which dynamically reduces treatment based on the tumor dynamics, might alleviate both issues. Utilizing in vitro time-lapse microscopy and stepwise model selection, we calibrate and validate a differential equation mathematical model, which we leverage to test different plausible adaptive treatment schedules. Our model indicates that adjusting the dosage, rather than skipping treatments, is more effective …

Unravelling the formation of characteristic aroma of traditional braised pork through untargeted and targeted flavoromics.

Untargeted flavoromics and targeted quantitative analysis of key aroma compounds, and analysis of dynamic change of aroma precursors concent … sion of glucose and amino acids from seasonings to lean meat promoted the consumption of endogenous ribose and amino acids in meat through Maillard reaction, and facilitated the formation of dimethyl trisulfide, dimethyl disulfide, methanethiol, and 2-furfural, which contributed to the meaty, sauce-like, and sweety aroma, thus formed the characteristic a …

Visualizing the DNA Damage Response in Purkinje Cells Using Cerebellar Organotypic Cultures.

Cerebellar Purkinje cells (PCs) exhibit a unique interplay of high metabolic rates, specific chromatin architecture, and extensive transcrip … the organotypic culture protocol, demonstrating that fluorescent imaging of protein-bound poly(ADP-ribose) (PAR) chains, a rapid and early DDR indicator, effectively reveals DDR dynamics in PCs within these cultures, in response to genotoxic stress.

NAMPT inhibition relieves intestinal inflammation by regulating macrophage activation in experimental necrotizing enterocolitis.

Nicotinamide phosphoribosyl transferase (NAMPT) is associated with various NAD+ -consuming enzymatic reactions. The precise role in intestin … evels, macrophage M1 polarization, and the expression of NAD+ -dependent enzymes, such as poly (ADP ribose) polymerase 1 (PARP1) and Sirt6. Consistently, the capacity of macrophages to phagocytose zymosan particles, as well as antibacterial activity, were impaired by FK866, whereas NMN supplementation to restore NAD+ levels reversed the changes in phagoc …

Multi-Omics of Familial Thoracic Aortic Aneurysm and Dissection: Calcium Transport Impairment Predisposes Aortas to Dissection.

Several genetic defects, including a mutation in myosin heavy chain 11 (Myh11), are reported to cause familial thoracic aortic aneurysm and … mechanisms that raise the cytosolic Ca2+ concentration-multiple calcium channel expression and ADP-ribose synthesis-were attenuated in Myh11ΔK/ΔK aortas. We suggest that the impairment of the Ca2+ influx attenuates aortic contraction and that suboptimal contraction predisposes the aorta to dissection.

Olaparib Attenuates Demyelination and Neuroinflammation in an Organotypic Slice Culture Model of Metachromatic Leukodystrophy.

Metachromatic leukodystrophy (MLD) is a severe demyelinating, autosomal recessive genetic leukodystrophy. The disease is underpinned by muta … sis. Moreover, such sulfatide-induced effects can be attenuated by the treatment with the poly (ADP-ribose) polymerase 1 (PARP-1) inhibitor Olaparib (IC50∼100 nM) suggesting that this small molecule may be neuroprotective and limit toxin-induced demyelination. Our data support the idea that sulfatide is a key driver of demyelination and neuroinflammation …

SF3B1 hotspot mutations confer sensitivity to PARP inhibition by eliciting a defective replication stress response.

SF3B1 hotspot mutations are associated with a poor prognosis in several tumor types and lead to global disruption of canonical splicing. Through synthetic lethal drug screens, we identify that SF3B1 mutant (SF3B1MUT) cells are selectively sensitive to poly (ADP-ribose) polymerase inhibitors (PARPi), independent of hotspot mutation and tumor site. SF3B1MUT cells display a defective response to PARPi-induced replication stress that occurs via downregulation of the cyclin-dependent kinase 2 interacting protein (CINP), leading to increased replication fork origin firing and loss of phosphorylated …

ATM deficiency confers specific therapeutic vulnerabilities in bladder cancer.

Ataxia-telangiectasia mutated (ATM) plays a central role in the cellular response to DNA damage and ATM alterations are common in several tu … adiation. Furthermore, ATM loss drives sensitivity to DNA repair-targeted agents including poly(ADP-ribose) polymerase (PARP) and Ataxia telangiectasia and Rad3 related (ATR) inhibitors. ATM loss alters the immune microenvironment and improves anti-PD1 response in preclinical bladder models but is not associated with improved anti-PD1/PD-L1 response in c …

Identification of an Alepterolic Acid Derivative as a Potent Anti-Breast-Cancer Agent via Inhibition of the Akt/p70S6K Signaling Pathway.

Alepterolic acid is a diterpene occurring in the fern Aleuritopteris argentea with potential biological activity that warrants further struc … ] alepterolamide, a significant increase in cleaved caspase-9, cleaved caspase-3, cleaved poly (ADP-ribose) polymerase (PARP) and Bax/Bcl2 ratio were observed in MCF-7 cells, leading to caspase-dependent apoptotic pathways. Further studies showed this compound promoted cellular apoptosis and inhibited migration in MCF-7 cells via modulation of the Akt/p7 …

Heavy-chain antibody targeting of CD38 NAD+ hydrolase ectoenzyme to prevent fibrosis in multiple organs.

The functionally pleiotropic ectoenzyme CD38 is a glycohydrolase widely expressed on immune and non-hematopoietic cells. By converting NAD+ to ADP-ribose and nicotinamide, CD38 governs organismal NAD+ homeostasis and the activity of NAD+-dependent cellular enzymes. CD38 has emerged as a major driver of age-related NAD+ decline underlying adverse metabolic states, frailty and reduced health span. CD38 is upregulated in systemic sclerosis (SSc), a chronic disease characterized by fibrosis in multiple organs. We sought to test the hypothesis that inhibition of the CD38 ecto-enzymatic activity usi…

PARP1 inhibition protects mice against Japanese encephalitis virus infection.

Japanese encephalitis (JE) is a vector-borne viral disease that causes acute encephalitis in children. Although vaccines have been developed against the JE virus (JEV), no effective antiviral therapy exists. Our study shows that inhibition of poly(ADP-ribose) polymerase 1 (PARP1), an NAD+-dependent (poly-ADP) ribosyl transferase, protects against JEV infection. Interestingly, PARP1 is critical for JEV pathogenesis in Neuro-2a cells and mice. Small molecular inhibitors of PARP1, olaparib, and 3-aminobenzamide (3-AB) significantly reduce clinical signs and viral load in the serum and brains of m…

An In-Depth Review of Niraparib in Ovarian Cancer: Mechanism of Action, Clinical Efficacy and Future Directions.

Niraparib is an oral, potent, highly selective poly-ADP ribose polymerase 1 (PARP1) and PARP2 inhibitor. In most developed countries, it is approved as a maintenance treatment for epithelial ovarian, fallopian tube, or primary peritoneal cancer in patients with complete or partial response to platinum-based therapy. These approvals are based on results of randomised, double-blind, placebo-controlled trials, particularly the NOVA trial and more recently the PRIMA trial. In this comprehensive review, we delve into the scientific basis of PARP inhibition, discussing both preclinical and clinical …

PARP7 negatively regulates the type I interferon response in cancer cells and its inhibition triggers antitumor immunity.

PARP7 is a monoPARP that catalyzes the transfer of single units of ADP-ribose onto substrates to change their function. Here, we identify PARP7 as a negative regulator of nucleic acid sensing in tumor cells. Inhibition of PARP7 restores type I interferon (IFN) signaling responses to nucleic acids in tumor models. Restored signaling can directly inhibit cell proliferation and activate the immune system, both of which contribute to tumor regression. Oral dosing of the PARP7 small-molecule inhibitor, RBN-2397, results in complete tumor regression in a lung cancer xenograft and induces tumor-speci…

The Ethyl Acetate Subfraction of Polygonum cuspidatum Root Containing Emodin Affect EBV Gene Expression and Induce EBV-Positive Cells Apoptosis.

Epstein-Barr virus (EBV), a human herpesvirus, is several human lymphoid malignancies-associated. Our earlier study found the effect of Poly … tive-oxygen species (ROS), activated the apoptosis-related proteins, cleaved caspase 3 and poly(ADP-ribose)polymerase (PARP), and increased the apoptosis percentage. Therefore, the Polygonum cuspidatum ethyl acetate subfraction containing emodin could be a therapeutic drug for EBV-related tumors.

PARP Inhibitors and Haematological Malignancies-Friend or Foe?

Since their introduction several years ago, poly (ADP-ribose) polymerase (PARP) inhibitors (PARPi) have become the standard of care for breast and gynaecological cancers with BRCA gene mutations. Given that PARPi act by exploiting defective DNA repair mechanisms within tumour cells, they should be ideally suited to combatting haematological malignancies where these pathways are notoriously defective, even though BRCA mutations are rare. To date, despite promising results in vitro, few clinical trials in humans for haematological malignancies have been performed, and additional investigation is…

DoE Optimization Empowers the Automated Preparation of Enantiomerically Pure [18F]Talazoparib and its In Vivo Evaluation as a PARP Radiotracer.

Given the clinical potential of poly(ADP-ribose) polymerases (PARP) imaging for the detection and stratification of various cancers, the development of novel PARP imaging probes with improved pharmacological profiles over established PARP imaging agents is warranted. Here, we present a novel 18F-labeled PARP radiotracer based on the clinically superior PARP inhibitor talazoparib. An automated radiosynthesis of [18F]talazoparib (RCY: 13 ± 3.4%; n = 4) was achieved using a "design of experiments" (DoE) optimized copper-mediated radiofluorination reaction. The chiral product was isolated from the…