The Use of Synthetic Hybrid Strains to Determine the Role of Replicon 3 in Virulence of the Burkholderia cepacia Complex.

Appl Environ Microbiol. 2017 Apr 21;:

Authors: Agnoli K, Freitag R, Gomes MC, Jenul C, Suppiger A, Mannweiler O, Frauenknecht C, Janser D, Vergunst AC, Eberl L

Abstract
The Burkholderia cepacia complex (Bcc) displays a wealth of metabolic diversity with great biotechnological potential, but the utilisation of these bacteria is limited by their opportunistic pathogenicity to humans. The third replicon of the Bcc, megaplasmid pC3 (0.5 to 1.4 Mb, previously chromosome 3), is important for various phenotypes, including virulence, antifungal and proteolytic activities, and the utilization of certain substrates. Approximately half of plasmid pC3 is well-conserved throughout sequenced Bcc members, while the other half is not. To better locate the regions responsible for the key phenotypes, pC3 mutant derivatives of B. cenocepacia H111 carrying large deletions (up to 0.58 Mb) were constructed with the aid of the FLP-FRT recombination system from Saccharomyces cerevisiae The conserved region was shown to confer near full virulence in both a Caenorhabditis elegans and a Galleria mellonella infection model. Antifungal activity was unexpectedly independent of the part of pC3 bearing a previously identified antifungal gene cluster, while proteolytic activity was dependent on the non-conserved part of pC3, which encodes the ZmpA protease. To investigate to what degree pC3-encoded functions are dependent on chromosomally-encoded functions, we transferred pC3 from Burkholderia cenocepacia K56-2 and Burkholderia lata 383 into other pC3-cured Bcc members. We found that although pC3 is highly important for virulence, it was the genetic background of the recipient that determined the pathogenicity level of the hybrid strain. Furthermore, we found that important phenotypes such as antifungal activity, proteolytic activity and some substrate utilisation capabilities can be transferred between Bcc members using pC3.Importance The Burkholderia cepacia complex (Bcc) is a group of closely-related bacteria with great biotechnological potential. Some strains produce potent antifungal compounds, can promote plant growth or degrade environmental pollutants. However, their agricultural potential is limited by their opportunistic pathogenicity, particularly for cystic fibrosis patients. Despite much study their virulence remains poorly understood. The third replicon, pC3, which is present in all Bcc isolates and is important for pathogenicity, stress resistance and production of antifungal compounds, has recently been reclassified from chromosome to megaplasmid. In this study we identified regions on pC3 important for virulence and antifungal activity, and investigated the role of the chromosomal background for the function of pC3 by exchanging the megaplasmid between different Bcc members. Our results may open a new avenue for the construction of antifungal but non-pathogenic Burkholderia hybrids. Such strains may have great potential as biocontrol strains for protecting fungal-borne diseases of plant crops.

PMID: 28432094 [PubMed - as supplied by publisher]

Co-colonisation with Aspergillus fumigatus and Pseudomonas aeruginosa is associated with poorer health in cystic fibrosis patients: an Irish registry analysis.

BMC Pulm Med. 2017 Apr 21;17(1):70

Authors: Reece E, Segurado R, Jackson A, McClean S, Renwick J, Greally P

Abstract
BACKGROUND: Pulmonary infection is the main cause of death in cystic fibrosis (CF). Aspergillus fumigatus (AF) and Pseudomonas aeruginosa (PA) are the most prevalent fungal and bacterial pathogens isolated from the CF airway, respectively. Our aim was to determine the effect of different colonisation profiles of AF and PA on the clinical status of patients with CF.
METHODS: A retrospective analysis of data from the Cystic Fibrosis Registry of Ireland from 2013 was performed to determine the effect of intermittent and persistent colonisation with AF or PA or co-colonisation with both microorganisms on clinical outcome measures in patients with CF. Key outcomes measured included forced expiratory volume in one second (FEV1), number of hospitalisations, respiratory exacerbations and antimicrobials prescribed, and complications of CF, including CF related diabetes (CFRD) and allergic bronchopulmonary aspergillosis (ABPA).
RESULTS: The prevalence of AF and PA colonisation were 11% (5% persistent, 6% intermittent) and 31% (19% persistent, 12% intermittent) in the Irish CF population, respectively. Co-colonisation with both pathogens was associated with a 13.8% reduction in FEV1 (p = 0.016), higher levels of exacerbations (p = 0.042), hospitalisations (p = 0.023) and antimicrobial usage (p = 0.014) compared to non-colonised patients and these clinical outcomes were comparable to those persistently colonised with PA. Intermittent and persistent AF colonisation were not associated with poorer clinical outcomes or ABPA. Patients with persistent PA had a higher prevalence of CFRD diagnosis (p = 0.012).
CONCLUSIONS: CF patients co-colonised with AF and PA had poor clinical outcomes comparable to patients persistently colonised with PA, emphasising the clinical significance of co-colonisation with these microorganisms.

PMID: 28431569 [PubMed - in process]

Whole Exome Sequencing Identification of Novel Candidate Genes in Patients with Proliferative Diabetic Retinopathy.

Vision Res. 2017 Apr 18;:

Authors: Ung C, Sanchez AV, Shen L, Davoudi S, Ahmadi T, Navarro-Gomez D, Chen CJ, Hancock H, Penman A, Hoadley S, Consugar M, Restrepo C, Shah VA, Arboleda-Velasquez JF, Sobrin L, Gai X, Kim LA

Abstract
Rare or novel gene variants in patients with proliferative diabetic retinopathy may contribute to disease development. We performed whole exome sequencing (WES) on patients at the phenotypic extremes of diabetic retinal complications: 57 patients diagnosed with proliferativediabetic retinopathy (PDR) as cases and 13 patients with no diabetic retinopathy despite at least 10 years of type 2 diabetes as controls. Thirty-one out of the 57 cases and all 13 controls were from the African American Proliferative Diabetic Retinopathy Study (AA). The rest of the cases were of mixed ethnicities (ME). WES identified 721 candidate genes with rare or novel non-synonymous variants found in at least one case with PDR and not present in any controls. After filtering for genes with null alleles in greater than two cases, 28 candidate genes were identified in our ME cases and 16 genes were identified in our AA cases. Our analysis showed rare and novel variants within these genes that could contribute to the development of PDR, including rare non-synonymous variants in FAM132A, SLC5A9, ZNF600, and TMEM217. We also identified previously unidentified variants in VEGFB and APOB. We found that VEGFB, VPS 13B, PHF21A, NAT1, ZNF600, PKHD1L1 expression was reduced in HRECs under high glucose conditions. In an exome sequence analysis of patients with PDR, we identified variants in genes that could contribute to pathogenesis. Seven of these genes were further validated and found to have reduced expression in human retinal endothelial cells under high glucose conditions, suggestive of an important role in the development of PDR.

PMID: 28431867 [PubMed - as supplied by publisher]

Xeroderma pigmentosum complementation group F: A rare cause of cerebellar ataxia with chorea.

J Neurol Sci. 2017 May 15;376:198-201

Authors: Carré G, Marelli C, Anheim M, Geny C, Renaud M, Rezvani HR, Koenig M, Guissart C, Tranchant C

Abstract
The complementation group F of Xeroderma pigmentosum (XP-F) is rare in the Caucasian population, and usually devoid of neurological symptoms. We report two cases, both Caucasian, who exhibited progressive cerebellar ataxia, chorea, a mild subcortical frontal cognitive impairment, and in one case severe polyneuropathy. Brain MRI demonstrated cerebellar (2/2) and cortical (1/2) atrophy. Both patients had only mild sunburn sensitivity and no skin cancer. Mini-exome sequencing approach revealed in ERCC4, two heterozygous mutations, one of which was never described (c.580-584+1delCCAAGG, exon 3), in the first case, and an already reported homozygous mutation, in the second case. These cases emphasize that XP-F is a rare cause of recessive cerebellar ataxia and can in some cases clinically mimic Huntington's disease due to chorea and executive impairment. The association of ataxia, chorea, and sun hypersensitivity are major guidance for the diagnosis, which should not be missed, in order to prevent skin neoplastic complications.

PMID: 28431612 [PubMed - in process]

Probing protein flexibility reveals a mechanism for selective promiscuity.

Elife. 2017 Apr 22;6:

Authors: Pabon NA, Camacho CJ

Abstract
Many eukaryotic regulatory proteins adopt distinct bound and unbound conformations, and use this structural flexibility to bind specifically to multiple partners. However, we lack an understanding of how an interface can select some ligands, but not others. Here, we present a molecular dynamics approach to identify and quantitatively evaluate the interactions responsible for this selective promiscuity. We apply this approach to the anti-cancer target PD-1 and its ligands PD-L1 and PD-L2. We discover that while unbound PD-1 exhibits a hard-to-drug hydrophilic interface, conserved specific triggers encoded in the cognate ligands activate a promiscuous binding pathway that reveals a flexible hydrophobic binding cavity. Specificity is then established by additional contacts that stabilize the PD-1 cavity into distinct bound-like modes. Collectively, our studies provide insight into the structural basis and evolution of multiple binding partners, and also suggest a biophysical approach to exploit innate binding pathways to drug seemingly undruggable targets.

PMID: 28432789 [PubMed - as supplied by publisher]

Genome characteristics of the proteorhodopsin-containing marine flavobacterium Polaribacter dokdonensis DSW-5.

J Microbiol. 2017 Apr 22;:

Authors: Yoon K, Song JY, Kwak MJ, Kwon SK, Kim JF

Abstract
Bacteria in the genus Polaribacter, belonging to the family Flavobacteriaceae, are typically isolated from marine environments. Polaribacter dokdonensis DSW-5, the type strain of the species, is a Gram-negative bacterium isolated from the East Sea of Korea. Whole genome shotgun sequencing was performed with the HiSeq 2000 platform and paired-end reads were generated at 188-fold coverage. The sequencing reads were assembled into two contigs with a total length of 3.08 Mb. The genome sequences of DSW-5 contain 2,776 proteincoding sequences and 41 RNA genes. Comparison of average nucleotide identities among six available Polaribacteria genomes including DSW-5 suggested that the DSW-5 genome is most similar to that of Polaribacter sp. MED152, which is a proteorhodopsin-containing marine bacterium. A phylogenomic analysis of the six Polaribacter strains and 245 Flavobacteriaceae bacteria confirmed a close relationship of the genus Polaribacter with Tenacibaculum and Kordia. DSW-5's genome has a gene encoding proteorhodopsin and genes encoding 85 enzymes belonging to carbohydrate-active enzyme families and involved in polysaccharide degradation, which may play important roles in energy metabolism of the bacterium in the marine ecosystem. With genes for 238 CAZymes and 203 peptidases, DSW-5 has a relatively high number of degrading enzymes for its genome size suggesting its characteristics as a free-living marine heterotroph.

PMID: 28432541 [PubMed - as supplied by publisher]

Systematic Synergy of Glucose and GLP-1 to Stimulate Insulin Secretion Revealed by Quantitative Phosphoproteomics.

Sci Rep. 2017 Apr 21;7(1):1018

Authors: Tang JS, Li QR, Li JM, Wu JR, Zeng R

Abstract
GLP-1 synergizes with glucose in regulating pancreatic β-cell function, including facilitating β-cell survival and insulin secretion. Though it has been widely accepted that phosphorylation is extremely important in regulating β-cell functions, our knowledge to the global mechanism is still limited. Here we performed a quantitative phosphoproteomics study to systematically present the synergistic regulation of INS-1E cell phosphoproteome mediated by glucose and GLP-1. We generated the largest pancreatic β-cell phosphoproteome by identifying 25,327 accurately localized phosphorylation sites on 5,389 proteins. Our results discovered several novel kinases regulated by glucose, GLP-1 or their synergism, and some of these kinases might act as downstream molecules of GLP-1 mediated PKA signaling cascade. A few phosphosites were regulated by both GLP-1 and glucose alone, and these target proteins were highly related to their biological function on pancreatic β-cells. Finally, we found glucose and GLP-1 executed their synergistic effect at multiple levels, especially at pathway level. Both GLP-1 and glucose participated in regulating every single step of the secretion pathway, and systematically synergized their effects in inducing insulin secretion.

PMID: 28432305 [PubMed - in process]

Quantitative Imaging of Cerebral Thromboemboli In Vivo: The Effects of Tissue-Type Plasminogen Activator.

Stroke. 2017 Apr 21;:

Authors: Kim DE, Kim JY, Schellingerhout D, Ryu JH, Lee SK, Jeon S, Lee JS, Kim J, Jang HJ, Park JE, Kim EJ, Kwon IC, Ahn CH, Nahrendorf M, Kim K

Abstract
BACKGROUND AND PURPOSE: Quantitative imaging for the noninvasive assessment of thrombolysis is needed to advance basic and clinical thrombosis-related research and tailor tissue-type plasminogen activator (tPA) treatment for stroke patients. We quantified the evolution of cerebral thromboemboli using fibrin-targeted glycol chitosan-coated gold nanoparticles and microcomputed tomography, with/without tPA therapy.
METHODS: We injected thrombi into the distal internal carotid artery in mice (n=50). Fifty-five minutes later, we injected fibrin-targeted glycol chitosan-coated gold nanoparticles, and 5 minutes after that, we treated animals with tPA or not (25 mg/kg). We acquired serial microcomputed tomography images for 24 hours posttreatment.
RESULTS: Thrombus burden at baseline was 784×10(3)±59×10(3) μm(2) for the tPA group (n=42) and 655×10(3)±103×10(3) μm(2) for the saline group (n=8; P=0.37). Thrombus shrinkage began at 0.5 to 1 hour after tPA therapy, with a maximum initial rate of change at 4603±957 μm(2)/min. The rate of change lowered to ≈61% level of the initial in hours 1 to 2, followed by ≈29% and ≈1% in hours 2 to 3 and 3 to 24, respectively. Thus, 85% of total thrombolysis over 24 hours (≈500 μm(2), equivalent to 64% of the baseline thrombus burden) occurred within the first 3 hours of treatment. Thrombus burden at 24 hours could be predicted at around 1.5 to 2 hours. Saline treatment was not associated with significant changes in the thrombus burden. Infarct size was smaller in the tPA group versus saline group (18.1±2.3 versus 45.8±3.3 mm(2); P<0.01). Infarct size correlated to final thrombus burden (r=0.71; P<0.01). Time to thrombolysis, completeness of thrombolysis, and tPA therapy were independent predictors of infarct size.
CONCLUSIONS: Thromboembolic burden and the efficacy of tPA therapy can be assessed serially, noninvasively, and quantitatively using high-resolution microcomputed tomography and a fibrin-binding nanoparticle imaging agent.

PMID: 28432262 [PubMed - as supplied by publisher]

N-terminal proteomics assisted profiling of the unexplored translation initiation landscape in Arabidopsis thaliana.

Mol Cell Proteomics. 2017 Apr 21;:

Authors: Willems P, Ndah E, Jonckheere V, Stael S, Sticker A, Martens L, Van Breusegem F, Gevaert K, Van Damme P

Abstract
Proteogenomics is an emerging research field yet lacking a uniform method of analysis. Proteogenomic studies in which N-terminal proteomics and ribosome profiling are combined, suggest that a high number of protein start sites are currently missing in genome annotations. We constructed a proteogenomic pipeline specific for the analysis of N-terminal proteomics data, with the aim of discovering novel translational start sites outside annotated protein coding regions. In summary, unidentified MS/MS spectra were matched to a specific N-terminal peptide library encompassing protein N-termini encoded in the Arabidopsis thaliana genome. After a stringent false discovery rate filtering, 157 protein N-termini compliant with N-terminal methionine excision specificity and indicative of translation initiation were found. These include N-terminal protein extensions and translation from transposable elements and pseudogenes. Gene prediction provided supporting protein-coding models for approximately half of the protein N-termini. Besides the prediction of functional domains (partially) contained within the newly predicted ORFs, further supporting evidence of translation was found in the recently released Araport11 genome re-annotation of Arabidopsis and computational translations of sequences stored in public repositories. Most interestingly, complementary evidence by ribosome profiling was found for 23 protein N-termini. Finally, by analyzing protein N-terminal peptides, an in silico analysis demonstrates the applicability of our N-terminal proteogenomics strategy in revealing protein-coding potential in species with well- and poorly-annotated genomes.

PMID: 28432195 [PubMed - as supplied by publisher]

Solithromycin: A novel ketolide antibiotic.

Am J Health Syst Pharm. 2017 Apr 21;:

Authors: Buege MJ, Brown JE, Aitken SL

Abstract
PURPOSE: The pharmacology, pharmacokinetics, pharmacodynamics, antimicrobial activity, clinical safety, and current regulatory status of solithromycin are reviewed.
SUMMARY: Solithromycin is a novel ketolide antibiotic developed for the treatment of community-acquired bacterial pneumonia (CABP). Its pharmacologic, pharmacokinetic, and pharmacodynamic properties provide activity against a broad range of intracellular organisms, including retained activity against pathogens displaying various mechanisms of macrolide resistance. Phase III clinical trials of solithromycin demonstrated noninferiority of both oral and i.v.-to-oral regimens of 5-7 days' duration compared with moxifloxacin for patients with moderately severe CABP. Nearly one third of patients receiving i.v. solithromycin experienced infusion-site reactions. Although no liver-related adverse events were reported in patients receiving oral solithromycin, more patients receiving i.v.-to-oral solithromycin experienced asymptomatic, transient transaminitis, with alanine transaminase levels of >3 to >5 times the upper limit, compared with those treated with moxifloxacin. These results led the Food and Drug Administration to conclude that the solithromycin new drug application was not approvable as filed, adding that the risk of hepatotoxicity had not yet been adequately characterized. The agency further recommended a comparative study of patients with CABP to include approximately 9,000 patients exposed to solithromycin in order to exclude drug-induced liver injury events occurring at a rate of 1 in 3,000 with 95% probability.
CONCLUSION: Solithromycin is a novel ketolide antibiotic with activity against a broad spectrum of intracellular organisms, including those displaying macrolide resistance. While demonstrating noninferiority to a current first-line agent in the treatment of CABP, concerns for drug-induced liver injury and infusion-site reactions have placed its regulatory future in doubt.

PMID: 28432048 [PubMed - as supplied by publisher]

Multicenter observational study of abobotulinumtoxinA neurotoxin in cervical dystonia: The ANCHOR-CD registry.

J Neurol Sci. 2017 May 15;376:84-90

Authors: Trosch RM, Espay AJ, Truong D, Gil R, Singer C, LeWitt PA, Lew MF, Tagliati M, Adler CH, Chen JJ, Marchese D, Comella CL

Abstract
BACKGROUND: The ANCHOR-CD prospective observational registry study evaluated the effectiveness of abobotulinumtoxinA in adult idiopathic cervical dystonia (CD) in clinical practice.
METHODS: Adults with CD were eligible. Treating physicians determined abobotulinumtoxinA dose and treatment interval. The primary endpoint was patient response rate (Toronto Western Spasmodic Torticollis Rating Scale [TWSTRS] score reduction≥25% and Patient Global Impression of Change [PGIC] score of +2 or +3 at Week 4 of Cycle 1).
RESULTS: 350 patients enrolled (75% women; mean age 59±13.6years; 27.4% botulinum neurotoxin-naive) and 347 received at least 1 treatment. The median abobotulinumtoxinA dose for Cycle 1 was 500 Units. At Week 4, the responder rate was 30.6% (n=304) and the TWSTRS total score decreased 27.4% from baseline. PGIC of at least "Much improved" was documented in 43.6% of patients and maintained in Cycles 2 through 4 (43.3%, 48.9%, and 52.8%, respectively). A total of 39 adverse events (31 study drug-related) were reported in 17 patients (5%); the most common were dysphagia (n=6), muscle weakness (n=4), and neck pain (n=3).
CONCLUSION: This study confirmed the beneficial effect of abobotulinumtoxinA on CD in routine clinical practice as measured by improvements in TWSTRS and PGIC. No new safety concerns were identified.

PMID: 28431634 [PubMed - in process]

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Repurposed drugs targeting eIF2α-P-mediated translational repression prevent neurodegeneration in mice.

Brain. 2017 Apr 19;:

Authors: Halliday M, Radford H, Zents KAM, Molloy C, Moreno JA, Verity NC, Smith E, Ortori CA, Barrett DA, Bushell M, Mallucci GR

Abstract
Signalling through the PERK/eIF2α-P branch of the unfolded protein response plays a critical role in controlling protein synthesis rates in cells. This pathway is overactivated in brains of patients with Alzheimer's disease and related disorders and has recently emerged as a promising therapeutic target for these currently untreatable conditions. Thus, in mouse models of neurodegenerative disease, prolonged overactivation of PERK/eIF2α-P signalling causes sustained attenuation of protein synthesis, leading to memory impairment and neuronal loss. Re-establishing translation rates by inhibition of eIF2α-P activity, genetically or pharmacologically, restores memory and prevents neurodegeneration and extends survival. However, the experimental compounds used preclinically are unsuitable for use in humans, due to associated toxicity or poor pharmacokinetic properties. To discover compounds that have anti-eIF2α-P activity suitable for clinical use, we performed phenotypic screens on a NINDS small molecule library of 1040 drugs. We identified two compounds, trazodone hydrochloride and dibenzoylmethane, which reversed eIF2α-P-mediated translational attenuation in vitro and in vivo. Both drugs were markedly neuroprotective in two mouse models of neurodegeneration, using clinically relevant doses over a prolonged period of time, without systemic toxicity. Thus, in prion-diseased mice, both trazodone and dibenzoylmethane treatment restored memory deficits, abrogated development of neurological signs, prevented neurodegeneration and significantly prolonged survival. In tauopathy-frontotemporal dementia mice, both drugs were neuroprotective, rescued memory deficits and reduced hippocampal atrophy. Further, trazodone reduced p-tau burden. These compounds therefore represent potential new disease-modifying treatments for dementia. Trazodone in particular, a licensed drug, should now be tested in clinical trials in patients.

PMID: 28430857 [PubMed - as supplied by publisher]

Growth-suppressive activity of raloxifene on liver cancer cells by targeting IL-6/GP130 signaling.

Oncotarget. 2017 Apr 06;:

Authors: Wang Y, Ma H, Zhao C, Liu T, Yan D, Jou D, Li H, Zhang C, Lü J, Li C, Lin J, Li S, Lin L

Abstract
BACKGROUND: Interleukin-6 (IL-6) is a multifunctional cytokine, which is involved in the regulation of differentiation and growth of certain types of tumor cells. Constitutive activation of Signal Transducer and Activator of Transcription 3 (STAT3) induced by IL-6 is frequently detected in liver cancer and has emerged as a viable molecular target for liver cancer treatment. However, few inhibitors targeting up-streams of STAT3 are available for the therapy of liver cancer. We reported the discovery of EVISTA (Raloxifene HCl) as novel inhibitor of IL-6/GP130 protein-protein interactions (PPIs) using multiple ligand simultaneous docking (MLSD) and drug repositioning. The possible effect of Raloxifene in STAT3 signaling or liver cancer cells is still unclear.
RESULTS: Raloxifene inhibited the P-STAT3 stimulated by IL-6, but not the induction of STAT1 and STAT6 phosphorylation by IFN-γ, IFN-α, and IL-4. Raloxifene inhibited STAT3 phosphorylation and resulted in the induction apoptosis on human liver cancer cell-lines. Raloxifene inhibited the targets of STAT3, such as Bcl-2, Bcl-xl and survivin and cell viability, cell migration, and colony formation in liver cancer cells. Further, daily administration of Raloxifene suppressed the Hep-G2 tumor growth in mice in vivo.
MATERIALS AND METHODS: The inhibitory effect on STAT3 phosphorylation and activity as well as cell viability, migration, and colony forming ability by Raloxifene was examined in human liver cancer cells. Tumor growth was detected via mouse xenograft tumor mode.
CONCLUSIONS: Our results suggest that Raloxifene is a potent IL-6/GP130 inhibitor and may be a chemoprevention agent for liver cancer by targeting persistent STAT3 signaling.

PMID: 28430601 [PubMed - as supplied by publisher]

Benserazide, a dopadecarboxylase inhibitor, suppresses tumor growth by targeting hexokinase 2.

J Exp Clin Cancer Res. 2017 Apr 20;36(1):58

Authors: Li W, Zheng M, Wu S, Gao S, Yang M, Li Z, Min Q, Sun W, Chen L, Xiang G, Li H

Abstract
BACKGROUND: Hexokinase (HK) is the rate-limiting enzyme in the first reaction of glycolysis. And Hexokinase 2 (HK2) is most closely related to malignant tumor which expresses at higher level compared with normal cells. HK2 plays a pivotal role in tumor initiation and maintenance, which provides a new target for cancer therapy.
METHODS: Structure-based virtual ligand screening was used in hit identification from ZINC Drug Database. Microscale thermophoresis assay was performed to evaluate the binding affinity. Enzyme inhibition, cytotoxicity, apoptosis, intracellular ATP level, mitochondrial membrane potential (MMP), glucose uptake and lactate production experiments were undertaken in SW480 cells to identify Benz as a HK2 inhibitor. Western blot was used to test protein expression. SW480 cells xenograft mouse models were used for in vivo study. Nano-particles of Benz were prepared to improve the antitumor efficacy and tumor targeting of Benz. HPLC was used to measure the concentration of free Benz in tumor tissues.
RESULTS: Benserazide (Benz), was identified as a selective HK2 inhibitor, could specifically bind to HK2 and significantly inhibit HK2 enzymatic activity in vitro. In addition, Benz reduced glucose uptake, lactate production and intracellular ATP level, and could cause cell apoptosis and an increased loss of MMP as well. In vivo study indicated that intraperitoneal (ip) injection of Benz at 300 and 600 mg/Kg suppressed cancer growth in tumor-bearing mice and no toxicity shown. To further improve the antitumor efficacy and tumor targeting of Benz, nano-particles of Benz was prepared. Liposomal Benz at 100 and 200 mg/Kg performed potent inhibitory effects on tumor-bearing mice, showing reduced dose and better efficacy.
CONCLUSIONS: Our study provides a new direction for the development of Benz and its analogues as novel antitumor agents for cancer therapy.

PMID: 28427443 [PubMed - in process]