Publications by authors named "Ritesh Thakare"

Here, we present a protocol for monitoring phagocytosis by M2-type macrophages using automated counting of phagocytic events with an imaging cytometer. We describe steps for isolating and differentiating peripheral blood mononuclear cell (PBMC)-derived monocytes into M2-like macrophages, preparing cancer cells expressing a green fluorescence marker, labeling with a pH-sensitive dye, and co-culturing with macrophages. We then outline procedures for enumerating phagocytic events using an imaging cytometer.

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Glioblastoma (GBM) is the most aggressive and frequently occurring type of malignant brain tumor in adults. The initiation, progression, and recurrence of malignant tumors are known to be driven by a small subpopulation of cells known as tumor-initiating cells or cancer stem cells (CSCs). GBM CSCs play a pivotal role in orchestrating drug resistance and tumor relapse.

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Studies on Hippo pathway regulation of tumorigenesis largely center on YAP and TAZ, the transcriptional co-regulators of TEAD. Here, we present an oncogenic mechanism involving VGLL and TEAD fusions that is Hippo pathway-related but YAP/TAZ-independent. We characterize two recurrent fusions, VGLL2-NCOA2 and TEAD1-NCOA2, recently identified in spindle cell rhabdomyosarcoma.

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CD24 is frequently overexpressed in ovarian cancer and promotes immune evasion by interacting with its receptor Siglec10, present on tumor-associated macrophages, providing a "don't eat me" signal that prevents targeting and phagocytosis by macrophages. Factors promoting CD24 expression could represent novel immunotherapeutic targets for ovarian cancer. Here, using a genome-wide CRISPR knockout screen, we identify GPAA1 (glycosylphosphatidylinositol anchor attachment 1), a factor that catalyzes the attachment of a glycosylphosphatidylinositol (GPI) lipid anchor to substrate proteins, as a positive regulator of CD24 cell surface expression.

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Solute carrier (SLC) transporters constitute a vast superfamily of transmembrane proteins tasked with regulating the transport of various substances such as metabolites, nutrients, ions, and drugs across cellular membranes. SLC transporters exhibit coordinated expression patterns across normal tissues, suggesting a tightly regulated regulatory network governing normal cellular functions. These transporters are crucial for the transport of various metabolites, including carbohydrates, proteins, lipids, and nucleic acids.

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In the ongoing battle against antimicrobial resistance, phenotypic drug tolerance poses a formidable challenge. This adaptive ability of microorganisms to withstand drug pressure without genetic alterations further complicating global healthcare challenges. Microbial populations employ an array of persistence mechanisms, including dormancy, biofilm formation, adaptation to intracellular environments, and the adoption of L-forms, to develop drug tolerance.

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Sulfur-containing classes of the scaffold "Arylthioindoles" have been evaluated for antibacterial activity; they demonstrated excellent potency against methicillin-resistant Staphylococcus aureus (MRSA) as well as against vancomycin-resistant strains and a panel of clinical isolates of resistant strains. In this study, we have elucidated the mechanism of action of lead compounds, wherein they target the cell wall of S. aureus.

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The advent of next-generation sequencing (NGS) has brought about a paradigm shift in genomics research, offering unparalleled capabilities for analyzing DNA and RNA molecules in a high-throughput and cost-effective manner. This transformative technology has swiftly propelled genomics advancements across diverse domains. NGS allows for the rapid sequencing of millions of DNA fragments simultaneously, providing comprehensive insights into genome structure, genetic variations, gene expression profiles, and epigenetic modifications.

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Three platinum(II)-N-heterocyclic carbene (NHC) compounds [Pt(L)Cl](PF) (1), [Pt(L)(COD)](PF) (2) and [Pt(L)Cl] (3) were synthesized bearing pyridyl-functionalized butenyl-tethered (LH) and -butyl tethered (LH) NHC ligands, and their antibacterial activity against clinically relevant human pathogens was evaluated. Complex 1 was designed to have one of its metal coordination sites masked with a hemilabile butenyl group. The antibacterial activity spectrum against the ESKAPE panel of pathogens shows superior activity of 1 compared to 2 and 3 against the Gram-positive pathogen.

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Tri and Tetra-substituted Methanes (TRSMs) are a significant structural motif in many approved drugs and prodrugs. There is increasing use of TRSM units in medicinal chemistry, and many derivatives are specifically designed to make drug-target interactions through new chemical space around TRSM moiety. In this perspective, we describe synthetic challenges for accessing a range of functionalized selective TRSMs and their molecular mechanism of action, especially as anti-infectives.

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Molnupiravir (MK-4482, EIDD-2801) is a promising broad-spectrum experimental antiviral developed by Merck & Co. It is a nucleoside analogue prodrug that undergoes rapid conversion into nucleoside triphosphate (NTP) by intracellular metabolic processes. NTP inhibits viral polymerase by acting as an alternative substrate.

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Mammalian cells do not produce chitin, an insoluble polymer of N-acetyl-D-glucosamine (GlcNAc), although chitin is a structural component of the cell wall of pathogenic microorganisms such as Candida albicans. Mammalian cells, including cells of the innate immune system elaborate chitinases, including chitotriosidase (Chit1), which may play a role in the anti-fungal immune response. In the current study, using knockout mice, we determined the role of Chit1 against systemic candidiasis.

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Antimicrobial resistance is a serious threat to human health worldwide, prompting research efforts on a massive scale in search of novel antibiotics to fill an urgent need for a remedy. Teixobactin, a macrocyclic depsipeptide natural product, isolated from uncultured bacteria (, displayed potent activity against several Gram-positive pathogenic bacteria. The distinct pharmacological profile and interesting structural features of teixobactin with nonstandard amino acid (three d-amino acids and l--enduracididine) residues attracted several research groups to work on this target molecule in search of novel antibiotics with new mechanism.

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Background: Antimicrobial resistance is an urgent threat affecting healthcare systems worldwide. Identification of novel molecules capable of escaping current resistance mechanisms and exhibiting potent activity against highly drug-resistant strains is the unmet need of the hour.

Methods: Whole cell growth inhibition assays were used to screen and identify novel inhibitors.

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Background: The emergence of drug-resistant bacteria is a major hurdle for effective treatment of infections caused by Mycobacterium tuberculosis and ESKAPE pathogens. In comparison with conventional drug discovery, drug repurposing offers an effective yet rapid approach to identifying novel antibiotics.

Methods: Ethyl bromopyruvate was evaluated for its ability to inhibit M.

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A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

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Background: Novel drug discovery against non-tuberculous mycobacteria is beset with a large number of challenges including the existence of myriad innate drug resistance mechanisms as well as a lack of suitable animal models, which hinders effective translation. In order to identify molecules acting via novel mechanisms of action, we screened the Library of Pharmacologically Active Compounds against non-tuberculous mycobacteria to identify such compounds.

Methods: Whole-cell growth inhibition assays were used to screen and identify novel inhibitors.

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Indiscriminate use of antibiotics globally has lead to an increase in emergence of drug-resistant pathogens under both nosocomial, as well as more worryingly, in community setting as well. Further, a decrease in the corporate interest and financial commitment has exerted increasing pressure on a rapidly dwindling antimicrobial drug discovery and developmental program. In this context, we have screened the Library of Pharmacologically Active Compounds (LOPAC, Sigma) against Staphylococcus aureus and Mycobacterium tuberculosis to identify potent novel antimicrobial molecules amongst non-antibiotic molecules.

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Drug repurposing of non-antimicrobials is a novel method to augment a seriously depleted drug pipeline for targeting drug-resistant pathogens. This article highlights the potent antimicrobial activity of Ivacaftor against Staphylococcus aureus, including vancomycin- and other multidrug-resistant strains. The potent activity of Ivacaftor in vivo is also demonstrated in a murine neutropenic thigh infection model.

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Background: We describe the antimicrobial susceptibility pattern of 100 typhoidal Salmonella isolates recovered from blood cultures and also investigate the association of decreased ciprofloxacin susceptibility with mutations in the genes coding for DNA gyrase and topoisomerase IV in 55 isolates.

Methods: The study was conducted between January 2013 and December 2015 at a tertiary care centre in north India. Antimicrobial susceptibility testing was performed by Kirby-Bauer disc diffusion and E-test.

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