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1.
Prostate ; 84(10): 977-990, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38654435

ABSTRACT

BACKGROUND: It is important to identify molecular features that improve prostate cancer (PCa) risk stratification before radical treatment with curative intent. Molecular analysis of historical diagnostic formalin-fixed paraffin-embedded (FFPE) prostate biopsies from cohorts with post-radiotherapy (RT) long-term clinical follow-up has been limited. Utilizing parallel sequencing modalities, we performed a proof-of-principle sequencing analysis of historical diagnostic FFPE prostate biopsies. We compared patients with (i) stable PCa (sPCa) postprimary or salvage RT, (ii) progressing PCa (pPCa) post-RT, and (iii) de novo metastatic PCa (mPCa). METHODS: A cohort of 19 patients with diagnostic prostate biopsies (n = 6 sPCa, n = 5 pPCa, n = 8 mPCa) and mean 4 years 10 months follow-up (diagnosed 2009-2016) underwent nucleic acid extraction from demarcated malignancy. Samples underwent 3'RNA sequencing (3'RNAseq) (n = 19), nanoString analysis (n = 12), and Illumina 850k methylation (n = 8) sequencing. Bioinformatic analysis was performed to coherently identify differentially expressed genes and methylated genomic regions (MGRs). RESULTS: Eighteen of 19 samples provided useable 3'RNAseq data. Principal component analysis (PCA) demonstrated similar expression profiles between pPCa and mPCa cases, versus sPCa. Coherently differentially methylated probes between these groups identified ~600 differentially MGRs. The top 50 genes with increased expression in pPCa patients were associated with reduced progression-free survival post-RT (p < 0.0001) in an external cohort. CONCLUSIONS: 3'RNAseq, nanoString and 850k-methylation analyses are each achievable from historical FFPE diagnostic pretreatment prostate biopsies, unlocking the potential to utilize large cohorts of historic clinical samples. Profiling similarities between individuals with pPCa and mPCa suggests biological similarities and historical radiological staging limitations, which warrant further investigation.


Subject(s)
Disease Progression , Prostatic Neoplasms , Humans , Male , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Prostatic Neoplasms/radiotherapy , Aged , Middle Aged , Biopsy , Genomics , Prostate/pathology , Neoplasm Metastasis , Cohort Studies
2.
Eur J Nucl Med Mol Imaging ; 51(10): 3009-3025, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38853153

ABSTRACT

PURPOSE: Prostate-specific membrane antigen (PSMA) is increasingly used to image prostate cancer in clinical practice. We sought to develop and test a humanised PSMA minibody IAB2M conjugated to the fluorophore IRDye 800CW-NHS ester in men undergoing robot-assisted laparoscopic radical prostatectomy (RARP) to image prostate cancer cells during surgery. METHODS: The minibody was evaluated pre-clinically using PSMA positive/negative xenograft models, following which 23 men undergoing RARP between 2018 and 2020 received between 2.5 mg and 20 mg of IR800-IAB2M intravenously, at intervals between 24 h and 17 days prior to surgery. At every step of the procedure, the prostate, pelvic lymph node chains and extra-prostatic surrounding tissue were imaged with a dual Near-infrared (NIR) and white light optical platform for fluorescence in vivo and ex vivo. Histopathological evaluation of intraoperative and postoperative microscopic fluorescence imaging was undertaken for verification. RESULTS: Twenty-three patients were evaluated to optimise both the dose of the reagent and the interval between injection and surgery and secure the best possible specificity of fluorescence images. Six cases are presented in detail as exemplars. Overall sensitivity and specificity in detecting non-lymph-node extra-prostatic cancer tissue were 100% and 65%, and 64% and 64% respectively for lymph node positivity. There were no side-effects associated with administration of the reagent. CONCLUSION: Intraoperative imaging of prostate cancer tissue is feasible and safe using IR800-IAB2M. Further evaluation is underway to assess the benefit of using the technique in improving completion of surgical excision during RARP. REGISTRATION: ISCRCTN10046036: https://www.isrctn.com/ISRCTN10046036 .


Subject(s)
Antigens, Surface , Glutamate Carboxypeptidase II , Optical Imaging , Prostatectomy , Prostatic Neoplasms , Male , Humans , Prostatectomy/methods , Prostatic Neoplasms/surgery , Prostatic Neoplasms/diagnostic imaging , Glutamate Carboxypeptidase II/metabolism , Antigens, Surface/metabolism , Optical Imaging/methods , Intraoperative Period , Middle Aged , Animals , Aged , Surgery, Computer-Assisted/methods , Mice
3.
BJU Int ; 132(5): 472-484, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37410655

ABSTRACT

OBJECTIVE: To review the current status of germline and somatic (tumour) genetic testing for prostate cancer (PCa), and its relevance for clinical practice. METHODS: A narrative synthesis of various molecular profiles related to their clinical context was carried out. Current guidelines for genetic testing and its feasibility in clinical practice were analysed. We report the main identified genetic sequencing results or functional genomic scores for PCa published in the literature or obtained from the French PROGENE study. RESULTS: The molecular alterations observed in PCa are mostly linked to disruption of the androgen receptor (AR) pathway or DNA repair deficiency. The main known germline mutations affect the BReast CAncer gene 2 (BRCA2) and homeobox B13 (HOXB13) genes, whereas AR and tumour protein p53 (TP53) are the genes with most frequent somatic alterations in tumours from men with metastatic PCa. Molecular tests are now available for detecting some of these germline or somatic alterations and sometimes recommended by guidelines, but their utilisation must combine rationality and feasibility. They can guide specific therapies, notably for the management of metastatic disease. Indeed, following androgen deprivation, targeted therapies for PCa currently include poly-(ADP-ribose)-polymerase (PARP) inhibitors, immune checkpoint inhibitors, and prostate-specific membrane antigen (PSMA)-guided radiotherapy. The genetic tests currently approved for targeted therapies remain limited to the detection of BRCA1 and BRCA2 mutation and DNA mismatch repair deficiency, while large panels are recommended for germline analyses, not only for inherited cancer predisposing syndrome, but also for metastatic PCa. CONCLUSIONS: Further consensus aligning germline with somatic molecular analysis in metastatic PCa is required, including genomics scars, emergent immunohistochemistry, or functional pre-screen imaging. With rapid advances in knowledge and technology in the field, continuous updating of guidelines to help the clinical management of these individuals, and well-conducted studies to evaluate the benefits of genetic testing are needed.

4.
Int J Mol Sci ; 24(16)2023 Aug 12.
Article in English | MEDLINE | ID: mdl-37628903

ABSTRACT

Prostate cancer is typically of acinar adenocarcinoma type but can occasionally present as neuroendocrine and/or ductal type carcinoma. These are associated with clinically aggressive disease, and the former often arises on a background of androgen deprivation therapy, although it can also arise de novo. Two prostate cancer cases were sequenced by exome capture from archival tissue. Case 1 was de novo small cell neuroendocrine carcinoma and ductal adenocarcinoma with three longitudinal samples over 5 years. Case 2 was a single time point after the development of treatment-related neuroendocrine prostate carcinoma. Case 1 showed whole genome doubling in all samples and focal amplification of AR in all samples except the first time point. Phylogenetic analysis revealed a common ancestry for ductal and small cell carcinoma. Case 2 showed 13q loss (involving RB1) in both adenocarcinoma and small cell carcinoma regions, and 3p gain, 4p loss, and 17p loss (involving TP53) in the latter. By using highly curated samples, we demonstrate for the first time that small-cell neuroendocrine and ductal prostatic carcinoma can have a common ancestry. We highlight whole genome doubling in a patient with prostate cancer relapse, reinforcing its poor prognostic nature.


Subject(s)
Carcinoma, Acinar Cell , Carcinoma, Ductal , Carcinoma, Small Cell , Lung Neoplasms , Prostatic Neoplasms , Small Cell Lung Carcinoma , Male , Humans , Prostatic Neoplasms/genetics , Androgen Antagonists , Phylogeny , Carcinoma, Ductal/genetics , Evolution, Molecular
5.
Nature ; 537(7619): 229-233, 2016 09 08.
Article in English | MEDLINE | ID: mdl-27501246

ABSTRACT

Chagas disease, leishmaniasis and sleeping sickness affect 20 million people worldwide and lead to more than 50,000 deaths annually. The diseases are caused by infection with the kinetoplastid parasites Trypanosoma cruzi, Leishmania spp. and Trypanosoma brucei spp., respectively. These parasites have similar biology and genomic sequence, suggesting that all three diseases could be cured with drugs that modulate the activity of a conserved parasite target. However, no such molecular targets or broad spectrum drugs have been identified to date. Here we describe a selective inhibitor of the kinetoplastid proteasome (GNF6702) with unprecedented in vivo efficacy, which cleared parasites from mice in all three models of infection. GNF6702 inhibits the kinetoplastid proteasome through a non-competitive mechanism, does not inhibit the mammalian proteasome or growth of mammalian cells, and is well-tolerated in mice. Our data provide genetic and chemical validation of the parasite proteasome as a promising therapeutic target for treatment of kinetoplastid infections, and underscore the possibility of developing a single class of drugs for these neglected diseases.


Subject(s)
Chagas Disease/drug therapy , Kinetoplastida/drug effects , Kinetoplastida/enzymology , Leishmaniasis/drug therapy , Proteasome Endopeptidase Complex/drug effects , Proteasome Inhibitors/pharmacology , Proteasome Inhibitors/therapeutic use , Pyrimidines/pharmacology , Triazoles/pharmacology , Trypanosomiasis, African/drug therapy , Animals , Chagas Disease/parasitology , Chymotrypsin/antagonists & inhibitors , Chymotrypsin/metabolism , Disease Models, Animal , Female , Humans , Inhibitory Concentration 50 , Leishmaniasis/parasitology , Mice , Molecular Structure , Molecular Targeted Therapy , Proteasome Inhibitors/adverse effects , Proteasome Inhibitors/classification , Pyrimidines/adverse effects , Pyrimidines/chemistry , Pyrimidines/therapeutic use , Species Specificity , Triazoles/adverse effects , Triazoles/chemistry , Triazoles/therapeutic use , Trypanosomiasis, African/parasitology
6.
Eur J Pediatr ; 180(6): 1941-1946, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33569662

ABSTRACT

Population-based screening studies have documented prevalence of celiac disease (CD) at 1% at age 7 years, but 90% of children remain undiagnosed. This prospective cohort study aims to examine whether observed differences in diagnosis rates of CD exist between children from different socioeconomic groups and how this has changed over a 12-year period. All children aged ≤15 years with a postcode within South West of England (SWE) diagnosed with CD during a 12-year period (1999-2010) when all diagnoses were based on endoscopic histology were included in the study. The incidence rates in socioeconomic groups were determined using the Index of Multiple Deprivation Score and Office of National Statistics population data. Four hundred fifteen children were diagnosed with CD; 65 within the City of Bristol (CoB). Diagnosis rate rose 4.2 times in SWE and 3.1 times in CoB between the first and last 4 years of the study. The rate was 1.6 times higher in the least socioeconomically deprived compared to most deprived (2.2 times in CoB), and the gap widened over the 12 years. Missed cases estimates for CoB and SWE are at least 83% and 91%, respectively.Conclusion: These findings suggest that while incidence of diagnosed CD in children has increased over a 12-year period, 83-91% remained undiagnosed. Socioeconomically deprived children are more likely to be underdiagnosed, and the gap between the least and most deprived has widened. To fully address massive underdiagnosis, further strategies including pilot studies using finger prick serological mass screening for CD in children entering primary schools are needed. What is Known: • Epidemiological studies record a 1% prevalence of celiac disease (CD), but up to 90% of children may remain undiagnosed. • Previous studies have documented an increased incidence of CD in higher socioeconomic groups, but proposed reasons remain conflicting. What is New: • Incidence of diagnosed CDhas gone up across all social classes but more so in higher socioeconomic groups and there is an increasing health/wealth gap. • This study estimates that 83-91% of children with CD are still being missed despite improved and easily available serological testing and suggest that population screening should be reconsidered.


Subject(s)
Celiac Disease , Celiac Disease/diagnosis , Celiac Disease/epidemiology , Child , England/epidemiology , Humans , Incidence , Prevalence , Prospective Studies
7.
Mol Cell Proteomics ; 13(2): 435-48, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24345785

ABSTRACT

Tetrahydrolipstatin (THL) is bactericidal but its precise target spectrum is poorly characterized. Here, we used a THL analog and activity-based protein profiling to identify target proteins after enrichment from whole cell lysates of Mycobacterium bovis Bacillus Calmette-Guérin cultured under replicating and non-replicating conditions. THL targets α/ß-hydrolases, including many lipid esterases (LipD, G, H, I, M, N, O, V, W, and TesA). Target protein concentrations and total esterase activity correlated inversely with cellular triacylglycerol upon entry into and exit from non-replicating conditions. Cellular overexpression of lipH and tesA led to decreased THL susceptibility thus providing functional validation. Our results define the target spectrum of THL in a biological species with particularly diverse lipid metabolic pathways. We furthermore derive a conceptual approach that demonstrates the use of such THL probes for the characterization of substrate recognition by lipases and related enzymes.


Subject(s)
Enzyme Inhibitors/pharmacology , Esterases/antagonists & inhibitors , Lactones/pharmacology , Mycobacterium bovis/drug effects , Mycobacterium bovis/enzymology , Mycobacterium bovis/growth & development , Bacteriological Techniques , Dose-Response Relationship, Drug , Drug Resistance, Bacterial/genetics , Enzyme Activation/drug effects , Gene Expression Regulation, Bacterial/drug effects , Lipase/antagonists & inhibitors , Lipase/genetics , Lipase/metabolism , Lipid Metabolism/drug effects , Molecular Targeted Therapy , Mycobacterium bovis/metabolism , Orlistat , Triglycerides/metabolism
8.
J Antimicrob Chemother ; 70(3): 857-67, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25587994

ABSTRACT

OBJECTIVES: The discovery and development of TB drugs has met limited success, with two new drugs approved over the last 40 years. Part of the difficulty resides in the lack of well-established in vitro or in vivo targets of potency and physicochemical and pharmacokinetic parameters. In an attempt to benchmark and compare such properties for anti-TB agents, we have experimentally determined and compiled these parameters for 36 anti-TB compounds, using standardized and centralized assays, thus ensuring direct comparability across drugs and drug classes. METHODS: Potency parameters included growth inhibition, cidal activity against growing and non-growing bacteria and activity against intracellular mycobacteria. Pharmacokinetic parameters included basic physicochemical properties, solubility, permeability and metabolic stability. We then attempted to establish correlations between physicochemical, in vitro and in vivo pharmacokinetic and pharmacodynamic indices to tentatively inform future drug discovery efforts. RESULTS: Two-thirds of the compounds tested showed bactericidal and intramacrophage activity. Most compounds exhibited favourable solubility, permeability and metabolic stability in standard in vitro pharmacokinetic assays. An analysis of human pharmacokinetic parameters revealed associations between lipophilicity and volume of distribution, clearance, plasma protein binding and oral bioavailability. Not surprisingly, most compounds with favourable pharmacokinetic properties complied with Lipinski's rule of five. CONCLUSIONS: However, most attempts to detect in vitro-in vivo correlations were unsuccessful, emphasizing the challenges of anti-TB drug discovery. The objective of this work is to provide a reference dataset for the TB drug discovery community with a focus on comparative in vitro potency and pharmacokinetics.


Subject(s)
Antitubercular Agents/pharmacology , Antitubercular Agents/pharmacokinetics , Mycobacterium tuberculosis/drug effects , Animals , Antitubercular Agents/chemistry , Cell Line , Chemical Phenomena , Drug Stability , Macrophages/microbiology , Mice , Microbial Sensitivity Tests , Microbial Viability/drug effects , Permeability , Solubility
9.
J Indian Prosthodont Soc ; 15(2): 187-90, 2015.
Article in English | MEDLINE | ID: mdl-26929510

ABSTRACT

Surgical resection of lips is a relatively rare procedure. A defective lip may cause the patient to feel socially vulnerable as well as functionally handicapped and the defect will influence the patient's self-esteem and body image. Patients with labial defects also experience speech problems along with drying and crusting of the tissues in the area of defect. The lip and cheek provide a valve mechanism for speech. Rehabilitation of patients with this type of surgery creates numerous challenges for both the surgical and the maxillofacial prosthetic teams. The goals of prosthetic treatment include regaining favorable speech and restoration of esthetics. This case report presents a 65-year-old woman who was referred for restoration of her lost lip. This case paper describes a quick and simple method of positioning magnets with lip prosthesis attached to maxillary denture and thus esthetics and speech of the patient is restored. Use of retention magnets simplify the clinical and laboratory phase retains the denture and makes it stable and comfortable for the patient. The advent of magnets has enhanced the dental practitioner's capabilities with a remarkably improved potential for increasing prosthesis stability and preserving tissue.

10.
J Biol Chem ; 288(43): 30883-91, 2013 Oct 25.
Article in English | MEDLINE | ID: mdl-24022489

ABSTRACT

Cyclomarin A (CymA) was identified as a mycobactericidal compound targeting ClpC1. However, the target was identified based on pulldown experiments and in vitro binding data, without direct functional evidence in mycobacteria. Here we show that CymA specifically binds to the N-terminal domain of ClpC1. In addition we have determined the co-crystal structure of CymA bound to the N-terminal domain of ClpC1 to high resolution. Based on the structure of the complex several mutations were engineered into ClpC1, which showed reduced CymA binding in vitro. The ClpC1 mutants were overexpressed in mycobacteria and two showed resistance to CymA, providing the first direct evidence that ClpC1 is the target of CymA. Phe(80) is important in vitro and in cells for the ClpC1-CymA interaction and this explains why other bacteria are resistant to CymA. A model for how CymA binding to the N-terminal domain of ClpC1 leads to uncontrolled proteolysis by the associated ClpP protease machinery is discussed.


Subject(s)
Bacterial Proteins/chemistry , Heat-Shock Proteins/chemistry , Models, Molecular , Mycobacterium tuberculosis/chemistry , Oligopeptides/chemistry , Bacterial Proteins/antagonists & inhibitors , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Crystallography, X-Ray , Heat-Shock Proteins/antagonists & inhibitors , Heat-Shock Proteins/genetics , Heat-Shock Proteins/metabolism , Mutation , Mycobacterium tuberculosis/genetics , Mycobacterium tuberculosis/metabolism , Oligopeptides/metabolism , Protein Binding , Protein Structure, Tertiary
11.
J Cell Biochem ; 115(11): 1974-84, 2014 Nov.
Article in English | MEDLINE | ID: mdl-24913975

ABSTRACT

The ß-catenin/Wnt signaling pathway is activated in many cancers and its constitutive activation has a central role in colorectal cancer pathogenesis. Recent studies have highlighted the role of microRNAs as novel regulators of gene expression including that of signaling intermediates from the Wnt signaling pathway. The purpose of our study was to determine the role of miR-29b in the regulation of Wnt signaling in human colorectal cancer cells. TOPFlash/FOPFlash reporter assays, gene expression studies by quantitative RT-PCR and western blot analysis were used to study the effect of ectopic expression of miR-29b on canonical Wnt signaling. miR-29b antagonized transactivation of ß-catenin target genes by downregulating coactivators of ß-catenin (TCF7L2, Snail, and BCL9L) in SW480 cells. miR-29b targeted the 3'UTR of BCL9L and decreased its expression with a consequent decrease in nuclear translocation of ß-catenin. Ectopic expression of miR-29b inhibited anchorage independent cell growth, promoted reversal of epithelial to mesenchymal transition and reduced the ability of conditioned medium from SW480 cells to induce in vitro tube formation in endothelial cells. These results have unraveled a novel role of miR-29b in Wnt signaling in human colorectal cancer cells with implications in the treatment of colorectal cancer.


Subject(s)
Colorectal Neoplasms/genetics , Colorectal Neoplasms/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Wnt Signaling Pathway , Cell Line, Tumor , DNA-Binding Proteins/genetics , Epithelial-Mesenchymal Transition , Gene Expression Regulation, Neoplastic , HCT116 Cells , HEK293 Cells , Humans , Snail Family Transcription Factors , Transcription Factor 7-Like 2 Protein/genetics , Transcription Factors/genetics , beta Catenin/metabolism
12.
Mol Microbiol ; 87(4): 744-55, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23240649

ABSTRACT

Mycobacterium tuberculosis (Mtb) is an aerobic bacterium that persists intracellularly in host macrophages and has evolved diverse mechanisms to combat and survive oxidative stress. Here we show a novel F(420) -dependent anti-oxidant mechanism that protects Mtb against oxidative stress. Inactivation of the fbiC gene in Mtb results in a cofactor F(420) -deficient mutant that is hypersensitive to oxidative stress and exhibits a reduction in NADH/NAD(+) ratios upon treatment with menadione. In agreement with the recent hypothesis on oxidative stress being an important component of the pathway resulting in cell death by bactericidal agents, F(420) (-) mutants are hypersensitive to mycobactericidal agents such as isoniazid, moxifloxacin and clofazimine that elevate oxidative stress. The Mtb deazaflavin-dependent nitroreductase (Ddn) and its two homologues Rv1261c and Rv1558 encode for an F(420) H(2) -dependent quinone reductase (Fqr) function leading to dihydroquinones. We hypothesize that Fqr proteins catalyse an F(420) H(2) -specific obligate two-electron reduction of endogenous quinones, thereby competing with the one-electron reduction pathway and preventing the formation of harmful cytotoxic semiquinones, thus protecting mycobacteria against oxidative stress and bactericidal agents. These findings open up an avenue for the inhibition of the F(420) biosynthesis pathway or Fqr-class proteins as a mechanism to potentiate the action of bactericidal agents.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antioxidants/metabolism , Bacterial Proteins/metabolism , Coenzymes/metabolism , Mycobacterium tuberculosis/metabolism , NAD(P)H Dehydrogenase (Quinone)/metabolism , Oxidative Stress , Antioxidants/chemistry , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/enzymology , Mycobacterium tuberculosis/genetics , NAD/metabolism , NAD(P)H Dehydrogenase (Quinone)/chemistry , NAD(P)H Dehydrogenase (Quinone)/genetics
13.
Anal Biochem ; 458: 27-36, 2014 Aug 01.
Article in English | MEDLINE | ID: mdl-24657360

ABSTRACT

Labeling of released asparagine-linked (N-linked) oligosaccharides from glycoproteins is commonly performed to aid in the separation and detection of the oligosaccharide. Of the many available oligosaccharide labels, 2-amino benzamide (2-AB) is a popular choice for providing a fluorescent product. The derivatization conditions can potentially lead to oligosaccharide desialylation. This work evaluated the extent of sialic acid loss during 2-AB labeling of N-linked oligosaccharides released from bovine fetuin, polyclonal human serum immunoglobulin G (IgG), and human α1-acid glycoprotein (AGP) as well as of sialylated oligosaccharide reference standards and found that for more highly sialylated oligosaccharides the loss is greater than the <2% value commonly cited. Manufacturers of glycoprotein biotherapeutics need to produce products with a consistent state of sialylation and, therefore, require an accurate assessment of glycoprotein sialylation.


Subject(s)
Asparagine/chemistry , Chromatography, High Pressure Liquid , N-Acetylneuraminic Acid/analysis , Oligosaccharides/analysis , ortho-Aminobenzoates/chemistry , Animals , Carbohydrate Sequence , Cattle , Chromatography, High Pressure Liquid/standards , Fetuins/chemistry , Fetuins/metabolism , Humans , Immunoglobulin G/chemistry , Immunoglobulin G/metabolism , Molecular Sequence Data , N-Acetylneuraminic Acid/standards , Oligosaccharides/standards , Orosomucoid/chemistry , Orosomucoid/metabolism , Reference Standards
14.
Bio Protoc ; 14(13): e5026, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-39007161

ABSTRACT

Diseases caused by trypanosomatid parasites remain a significant unmet medical need for millions of people globally. Trypanosomatid parasites such as Trypanosoma cruzi and subspecies of Trypanosoma brucei cause Chagas disease and human African trypanosomiasis (HAT), respectively. Although efforts to find novel treatments have been successful for HAT, Chagas disease is still treated with decades-old therapies that suffer from long treatment durations and severe safety concerns. We recently described the identification and characterization of the cyanotriazole compound class that kills trypanosomes, in vitro and in vivo, by selective inhibition of the trypanosome nuclear topoisomerase II enzyme. To evaluate whether inhibition of the topoisomerase II enzyme led to parasite death due to lethal double-strand DNA breaks, we developed assays for detecting DNA damage in both intracellular amastigotes of T. cruzi and bloodstream-form T. brucei by using the canonical DNA damage marker γH2A. Herein, this article describes the protocols for detecting DNA damage using an immunofluorescence assessment of γH2A by microscopy in trypanosome parasites. Key features • Immunofluorescence-based assay to detect the γH2A response in T. brucei and T. cruzi parasites. • Robust DNA damage pathway-based cellular assays to evaluate topoisomerase II poisons' ability to cause DNA damage. • A 384-well plate-based T. cruzi protocol allows high-resolution and high-throughput evaluation of compounds that cause DNA damage by measuring γH2A in intracellular parasites. • This assay could be modifiable for evaluation of DNA damage responses in various intracellular and extracellular eukaryotic pathogens.

15.
Genome Med ; 16(1): 35, 2024 02 19.
Article in English | MEDLINE | ID: mdl-38374116

ABSTRACT

BACKGROUND: Extension of prostate cancer beyond the primary site by local invasion or nodal metastasis is associated with poor prognosis. Despite significant research on tumour evolution in prostate cancer metastasis, the emergence and evolution of cancer clones at this early stage of expansion and spread are poorly understood. We aimed to delineate the routes of evolution and cancer spread within the prostate and to seminal vesicles and lymph nodes, linking these to histological features that are used in diagnostic risk stratification. METHODS: We performed whole-genome sequencing on 42 prostate cancer samples from the prostate, seminal vesicles and lymph nodes of five treatment-naive patients with locally advanced disease. We spatially mapped the clonal composition of cancer across the prostate and the routes of spread of cancer cells within the prostate and to seminal vesicles and lymph nodes in each individual by analysing a total of > 19,000 copy number corrected single nucleotide variants. RESULTS: In each patient, we identified sample locations corresponding to the earliest part of the malignancy. In patient 10, we mapped the spread of cancer from the apex of the prostate to the seminal vesicles and identified specific genomic changes associated with the transformation of adenocarcinoma to amphicrine morphology during this spread. Furthermore, we show that the lymph node metastases in this patient arose from specific cancer clones found at the base of the prostate and the seminal vesicles. In patient 15, we observed increased mutational burden, altered mutational signatures and histological changes associated with whole genome duplication. In all patients in whom histological heterogeneity was observed (4/5), we found that the distinct morphologies were located on separate branches of their respective evolutionary trees. CONCLUSIONS: Our results link histological transformation with specific genomic alterations and phylogenetic branching. These findings have implications for diagnosis and risk stratification, in addition to providing a rationale for further studies to characterise the genetic changes causally linked to morphological transformation. Our study demonstrates the value of integrating multi-region sequencing with histopathological data to understand tumour evolution and identify mechanisms of prostate cancer spread.


Subject(s)
Prostatic Neoplasms , Male , Humans , Phylogeny , Prostatic Neoplasms/genetics , Prostatic Neoplasms/pathology , Prostate/pathology , Lymphatic Metastasis/pathology , Seminal Vesicles/pathology
16.
Antimicrob Agents Chemother ; 57(1): 168-76, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23089752

ABSTRACT

The subunit ε of bacterial F(1)F(O) ATP synthases plays an important regulatory role in coupling and catalysis via conformational transitions of its C-terminal domain. Here we present the first low-resolution solution structure of ε of Mycobacterium tuberculosis (Mtε) F(1)F(O) ATP synthase and the nuclear magnetic resonance (NMR) structure of its C-terminal segment (Mtε(103-120)). Mtε is significantly shorter (61.6 Å) than forms of the subunit in other bacteria, reflecting a shorter C-terminal sequence, proposed to be important in coupling processes via the catalytic ß subunit. The C-terminal segment displays an α-helical structure and a highly positive surface charge due to the presence of arginine residues. Using NMR spectroscopy, fluorescence spectroscopy, and mutagenesis, we demonstrate that the new tuberculosis (TB) drug candidate TMC207, proposed to bind to the proton translocating c-ring, also binds to Mtε. A model for the interaction of TMC207 with both ε and the c-ring is presented, suggesting that TMC207 forms a wedge between the two rotating subunits by interacting with the residues W15 and F50 of ε and the c-ring, respectively. T19 and R37 of ε provide the necessary polar interactions with the drug molecule. This new model of the mechanism of TMC207 provides the basis for the design of new drugs targeting the F(1)F(O) ATP synthase in M. tuberculosis.


Subject(s)
Antitubercular Agents/chemistry , Bacterial Proteins/antagonists & inhibitors , Mitochondrial Proton-Translocating ATPases/antagonists & inhibitors , Protein Subunits/antagonists & inhibitors , Quinolines/chemistry , Amino Acid Sequence , Bacterial Proteins/chemistry , Bacterial Proteins/genetics , Diarylquinolines , Escherichia coli/genetics , Mitochondrial Proton-Translocating ATPases/chemistry , Mitochondrial Proton-Translocating ATPases/genetics , Molecular Docking Simulation , Molecular Sequence Data , Mutagenesis, Site-Directed , Mycobacterium tuberculosis/chemistry , Mycobacterium tuberculosis/drug effects , Mycobacterium tuberculosis/enzymology , Nuclear Magnetic Resonance, Biomolecular , Protein Subunits/chemistry , Protein Subunits/genetics , Protons , Recombinant Proteins/antagonists & inhibitors , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Sequence Alignment , Spectrometry, Fluorescence
17.
Anal Chem ; 85(2): 1138-45, 2013 Jan 15.
Article in English | MEDLINE | ID: mdl-23234263

ABSTRACT

Heparan sulfate (HS) and chondroitin sulfate/dermatan sulfate (CS/DS) glycosaminoglycans (GAGs) participate in many important biological processes. Quantitative disaccharide analysis of HS and CS/DS is essential for the characterization of GAGs and enables modeling of the GAG domain structure. Methods involving enzymatic digestion and chemical depolymerization have been developed to determine the type and location of sulfation/acetylation modifications as well as uronic acid epimerization. Enzymatic digestion generates disaccharides with Δ-4,5-unsaturation at the nonreducing end. Chemical depolymerization with nitrous acid retains the uronic acid epimerization. This work shows the use of hydrophilic interaction liquid chromatography mass spectrometry (HILIC-MS) for quantification of both enzyme-derived and nitrous acid depolymerization products for structural analysis of HS and CS/DS. This method enables biomedical researchers to determine complete disaccharide profiles on GAG samples using a single LC-MS platform.


Subject(s)
Disaccharides/analysis , Glycosaminoglycans/chemistry , Chromatography, Liquid , Hydrophobic and Hydrophilic Interactions , Mass Spectrometry
18.
J Bioenerg Biomembr ; 45(1-2): 121-9, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23104121

ABSTRACT

Tuberculosis, caused by the strain Mycobacterium tuberculosis, is in focus of interest due to the emergence of multi- and extensive drug-resistant TB strains. The F(1)F(O) ATP synthase is one of the essential enzymes in energy requirement of both proliferating aerobic and hypoxic dormant stage of mycobacterium life cycle, and therefore a potential TB drug target. Subunit γ of F-ATP synthases plays an important role in coupling and catalysis via conformational transitions of its N- and C-termini as well as the bottom segment of the globular domain of γ, which is in close proximity to the rotating and ion-pumping c-ring. Here we describe the first production, purification and low resolution solution structure of subunit γ (γ(1-204), Mtγ(1-204)) of the M. tuberculosis F-ATP synthase. Mtγ(1-204) is a pear-like shaped protein with a molecular weight of 23 ± 2 kDa. Protein sequence analysis of Mtγ revealed differences in the amino acid composition to γ subunits from other sources, in particular the presence of a unique stretch of 13 amino acid residues (Mtγ(165-178)). NMR studies showed that Mtγ(165-178) forms a loop of polar residues. Mtγ(165-178) has been aligned at the bottom of the globular domain of the Escherichia coli subunit γ, being in close vicinity to the polar residues R41, Q42, E44 and Q46 (M. tuberculosis nomenclature) of the c-ring. The putative role(s) of Mtγ(165-178) in coupling and as a potential drug target are discussed.


Subject(s)
Bacterial Proteins/chemistry , Mycobacterium tuberculosis/enzymology , Protein Subunits/chemistry , Proton-Translocating ATPases/chemistry , Antitubercular Agents/chemistry , Antitubercular Agents/therapeutic use , Bacterial Proteins/antagonists & inhibitors , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Catalysis , Drug Delivery Systems , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/therapeutic use , Mycobacterium tuberculosis/genetics , Nuclear Magnetic Resonance, Biomolecular , Protein Structure, Secondary , Protein Subunits/antagonists & inhibitors , Protein Subunits/metabolism , Proton-Translocating ATPases/antagonists & inhibitors , Proton-Translocating ATPases/genetics , Proton-Translocating ATPases/metabolism , Recombinant Proteins/antagonists & inhibitors , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Tuberculosis/drug therapy , Tuberculosis/enzymology
19.
J Contemp Dent Pract ; 14(6): 1151-5, 2013 Nov 01.
Article in English | MEDLINE | ID: mdl-24858766

ABSTRACT

UNLABELLED: There is disagreement about the association between missing teeth and the presence of temporomandibular disorder (TMD). AIM: To investigate whether, the span of edentulousness, gender, number of quadrants involved, pathological migration and the type of kennedy's classification are related to the temporomandibular joint (TMJ) dysfunction signs. MATERIALS AND METHODS: Clinical examination of 250 patients (males 99 and females 151) was done among the age group of 35 to 45 years. The patients were partially edentulous for 6 months or more and did not wear any kind of prosthesis. RESULTS: Among 250 subjects, females showed more TMJ dysfunction signs. Clicking sounds were present in 46.5%, mandibular deviation was present in 40% of individuals, TMJ tenderness was observed in 32% and masseter was involved in 32% of individual. Temporomandibular joint dysfunction signs in relation to pathologic migration of teeth show that clicking and mandibular deviation was present in 54.5 and 49.2% and among muscles masseter muscle tenderness 41.9% was more commonly present. Masseter muscle tenderness 64.1% was seen in individuals who were edentulous for more than 5 years. CONCLUSION: Females subjects had a significantly higher prevalence of TMJ dysfunction signs then male subjects. As the span and time of edentulousness, the number of missing teeth and the number of quadrant involved increased, the signs of dysfunction became more prevalent. Among the TMJ dysfunction signs deviation and clicking sound were most frequently observed. The masseter muscle was most commonly affected and demonstrated muscle tenderness.


Subject(s)
Jaw, Edentulous, Partially/epidemiology , Temporomandibular Joint Dysfunction Syndrome/epidemiology , Adult , Cross-Sectional Studies , Female , Humans , India/epidemiology , Jaw, Edentulous, Partially/classification , Male , Mandible/physiopathology , Masseter Muscle/physiopathology , Middle Aged , Myalgia/epidemiology , Prevalence , Range of Motion, Articular/physiology , Sex Factors , Sound , Tooth Migration/epidemiology
20.
Trends Parasitol ; 39(4): 260-271, 2023 04.
Article in English | MEDLINE | ID: mdl-36803572

ABSTRACT

While prevention is a bedrock of public health, innovative therapeutics are needed to complement the armamentarium of interventions required to achieve disease control and elimination targets for neglected diseases. Extraordinary advances in drug discovery technologies have occurred over the past decades, along with accumulation of scientific knowledge and experience in pharmacological and clinical sciences that are transforming many aspects of drug R&D across disciplines. We reflect on how these advances have propelled drug discovery for parasitic infections, focusing on malaria, kinetoplastid diseases, and cryptosporidiosis. We also discuss challenges and research priorities to accelerate discovery and development of urgently needed novel antiparasitic drugs.


Subject(s)
Malaria , Parasitic Diseases , Humans , Drug Discovery , Parasitic Diseases/drug therapy , Antiparasitic Agents/pharmacology , Antiparasitic Agents/therapeutic use , Malaria/drug therapy , Technology
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