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1.
Mol Cancer Ther ; 2024 May 27.
Article in English | MEDLINE | ID: mdl-38797955

ABSTRACT

AB598 is a CD39 inhibitory antibody being pursued for the treatment of solid tumors in combination with chemotherapy and immunotherapy. CD39 metabolizes extracellular ATP (eATP), an alarmin capable of promoting anti-tumor immune responses, into adenosine, an immuno-inhibitory metabolite. By inhibiting CD39, the consumption of eATP is reduced, resulting in a pro-inflammatory milieu in which eATP can activate myeloid cells to promote anti-tumor immunity. The preclinical characterization of AB598 provides a mechanistic rationale for combining AB598 with chemotherapy in the clinic. Chemotherapy can induce ATP release from tumor cells and, when preserved by AB598, both chemotherapy-induced eATP and exogenously added ATP promote the function of monocyte-derived dendritic cells via P2Y11 signaling. Inhibition of CD39 in the presence of ATP can promote inflammasome activation in in vitro-derived macrophages, an effect mediated by P2X7. In a MOLP8 murine xenograft model, AB598 results in full inhibition of intratumoral enzymatic activity, an increase in intratumoral ATP, a decrease of extracellular CD39 on tumor cells, and ultimately, control of tumor growth. In cynomolgus monkeys, systemically dosed AB598 results in effective enzymatic inhibition in tissues, full peripheral and tissue target engagement, and a reduction in cell surface CD39 both in tissues and in the periphery. Taken together, these data support a promising therapeutic strategy of harnessing the eATP generated by standard-of-care chemotherapies to prime the tumor microenvironment for a productive anti-tumor immune response.

3.
Mol Biol Rep ; 51(1): 407, 2024 Mar 09.
Article in English | MEDLINE | ID: mdl-38460010

ABSTRACT

BACKGROUND: Lack of efficient transformation protocol continues to be a major bottleneck for successful genome editing or transgenic development in wheat. An in planta transformation method was developed in Indian bread wheat in earlier study (Vasil et al. in Nat Biotechnol 10:667-674, 1992) which was labour-intensive and time-consuming. In the present study, in planta transformation method was improved to make it simple, efficient, less labour-intensive and time-saving. METHODS AND RESULTS: PCR-based screening for generated transformants at T0 stage was introduced in this method. Shoot apical meristem of two days old wheat seedling was inoculated with the routine active culture of Agrobacterium tumefaciens harboring plasmid pCAMBIA1300-Ubi-GFP having gene GFP under the control of Zea mays ubiquitin promoter. PCR analysis at T0 stage confirmed 27 plants to be transgene positive. These 27 plants were only taken to the next generation (T1) and the rest were discarded. At T1 generation 6 plants were analyzed to be PCR positive. Out of them, 4 plants were confirmed to have stable integration of transgene (GFP). Fluorescent microscopy at T1 stage confirmed the 4 Southern hybridization positive plants to be expressing reporter gene GFP. CONCLUSIONS: Screening at T0 stage, reduced the load of plants to be taken to T1 generation and their screening thereof at T1 with no overall loss in transformation efficiency. We successfully transformed wheat genotype HD2894 with 3.33% transformation efficiency using a simple, effective method which was less labour-intensive and less time-consuming. This method may be utilized to develop wheat transgenic as well as genome edited lines for desirable traits.


Subject(s)
Agrobacterium tumefaciens , Triticum , Triticum/genetics , Plants, Genetically Modified/genetics , Transformation, Genetic , Agrobacterium tumefaciens/genetics , Transgenes
4.
Prostate Cancer Prostatic Dis ; 27(1): 109-115, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37620427

ABSTRACT

BACKGROUND: Management of urinary symptoms in elderly patients with benign prostatic hyperplasia (BPH) is complex given challenges with medications and invasive surgeries. Rezum, a minimally invasive water vapor therapy, is an emerging alternative. We compare real-world Rezum outcomes between young and elderly patients over 4 years. METHODS: We retrospectively analyzed a multiethnic population treated with Rezum at a single center between 2017-2019. Patients were stratified into young (<65 years) or elderly (≥65 years) cohorts. International Prostate Symptom Score (IPSS), Quality of Life (QoL), maximum urinary flow rate (Qmax), decisional regret scores, and adverse events (AEs) were assessed at baseline, 1-, 3-, 6-, 12-, and/or 48-months. Descriptive statistics were compared using t-tests, Chi-squared, or Mann-Whitney U tests. Changes in outcomes were assessed using Wilcoxon signed-rank tests, stratified by age. RESULTS: 256 patients - 146 (57%) young and 110 (43%) elderly - were included. The majority were Asian (33.2%) or non-Hispanic Black (28.9%). Significant improvements were observed in the combined cohort at 4-years in IPSS, QoL, and Qmax when compared to baseline (all p < 0.05). Between the age cohorts, there were no significant differences in IPSS, QoL, or Qmax at any follow-up. Within both cohorts, significant improvements in IPSS and QoL were found from baseline to all follow-ups. In the young cohort, Qmax was significantly improved from baseline to all follow-ups while in the elderly cohort, this was observed only at the 3-month follow-up. No significant differences in AEs or regret was found between cohorts. There was no significant difference in 4-year surgical retreatment rates between cohorts (elderly 4.0% vs young 4.4%, p = 0.86). CONCLUSIONS: There were no significant differences in IPSS, QoL, or AEs between elderly and younger men over 4 years following Rezum, suggesting comparable benefits and risks. Future research is warranted to clarify the impact of Rezum on Qmax in elderly men.


Subject(s)
Lower Urinary Tract Symptoms , Prostatic Hyperplasia , Prostatic Neoplasms , Male , Humans , Aged , Quality of Life , Lower Urinary Tract Symptoms/epidemiology , Retrospective Studies , Treatment Outcome , Prostatic Hyperplasia/surgery
5.
Food Bioproc Tech ; : 1-12, 2023 May 13.
Article in English | MEDLINE | ID: mdl-37363378

ABSTRACT

The metabolic actions of storage fungi and other microorganisms can cause spoilage and post-harvest losses in agricultural commodities, including flaxseed. These microbial contaminants are oxidized with hydroxyl radicals that are efficiently generated when ozone, hydrogen peroxide (H2O2) and ultraviolet (UV) light react in an advanced oxidative process (AOP). The present work explores what we believe is the first application of an AOP technology to reduce mould on whole brown and yellow flaxseed. The impact of AOP on storage and quality parameters was assessed by measuring the fatty acid value (FAV), germination rate, moisture content (MC) and visible mould growth after 12 weeks of storage at 30°C and 75% relative humidity (RH). Under these conditions, the yellow decontaminated flaxseed showed a 31% decrease in the number of seeds with visible mould without any adverse effect on germination rate, FAV and MC. In contrast, the same AOP treatment created an insignificant decrease in mould in stored brown flaxseed, at the cost of decreasing the germination rate and increasing FAV. The adverse effects of AOP on brown flaxseed were not readily apparent but became measurable after storage. Moreover, Fourier transform infrared (FTIR) spectroscopy was utilized to explore the rationale behind the different reactions of flaxseed varieties to AOP. The corresponding results indicated that the tolerance of yellow flaxseed to AOP might be related to its richness in olefins. The authors believe that technologies that harness advanced oxidative processes open new horizons in decontamination beyond ozone alone and towards increasing the shelf life of various agri-food products.

6.
Neurosci Lett ; 808: 137268, 2023 06 21.
Article in English | MEDLINE | ID: mdl-37100222

ABSTRACT

The objective of this study is to investigate nonlinear neural dynamics of chronic patients with schizophrenia following 3 months of cognitive remediation and to find correlations with neuropsychological measures of cognition. Twenty nine patients were randomized to Cognitive Training (CT) and Treatment as Usual (TAU) group. The system complexity is estimated by Correlation Dimension (D2) and Largest Lyapunov Exponent (LLE) from the reconstructed attractor of the underlying system. Significant increase in dimensional complexity (D2) over time is observed in prefrontal and medial frontal-central regions in eyes open and arithmetic condition; and posterior parietal-occipital region under eyes closed after 3 months. Dynamical complexity (LLE) significantly decreased over time in medial left central region under eyes closed and eyes open condition; prefrontal region in eyes open and lateral right temporal region in arithmetic condition. Interaction is significant for medial left central region with TAU group exhibiting greater decrease in LLE compared to CT group. The CT group showed significant correlation of increased D2 with focused attention. In this study it is found that patients with schizophrenia exhibit higher dimensional and lower dynamical complexity over time indicating improvement in neurodynamics of underlying physiological system.


Subject(s)
Cognitive Remediation , Schizophrenia , Humans , Schizophrenia/therapy , Electroencephalography , Brain , Cognition/physiology
7.
Cell Rep ; 41(10): 111788, 2022 12 06.
Article in English | MEDLINE | ID: mdl-36476875

ABSTRACT

A collective cell motility event that occurs during Drosophila eye development, ommatidial rotation (OR), serves as a paradigm for signaling-pathway-regulated directed movement of cell clusters. OR is instructed by the EGFR and Notch pathways and Frizzled/planar cell polarity (Fz/PCP) signaling, all of which are associated with photoreceptor R3 and R4 specification. Here, we show that Abl kinase negatively regulates OR through its activity in the R3/R4 pair. Abl is localized to apical junctional regions in R4, but not in R3, during OR, and this apical localization requires Notch signaling. We demonstrate that Abl and Notch interact genetically during OR, and Abl co-immunoprecipitates in complexes with Notch in eye discs. Perturbations of Abl interfere with adherens junctional organization of ommatidial preclusters, which mediate the OR process. Together, our data suggest that Abl kinase acts directly downstream of Notch in R4 to fine-tune OR via its effect on adherens junctions.


Subject(s)
Drosophila , Animals , Cell Movement
8.
J Vector Borne Dis ; 59(1): 29-36, 2022.
Article in English | MEDLINE | ID: mdl-35708401

ABSTRACT

Diagnosis of malaria is a prominent challenge due to the endemic nature of infection. Malaria poses a great threat to global public health. The disease can be diagnosed by several techniques out of which microscopy is a known gold standard. High sensitivity of molecular techniques is making them more reliable and popular as tools for diagnosis of malaria. However, new methods are required which can fulfill the criteria of being Point of Care Test (POCT) as defined by WHO. Loop-mediated isothermal amplification (LAMP) technique amplifies DNA in an isothermal condition, and surpasses the disadvantages of conventional molecular techniques such as polymerase chain reaction. Multiplex LAMP, a modification of LAMP may emerge as a new POC for malaria diagnosis. This review deals with the use of LAMP and multiplex LAMP in diagnosis of malaria and its prospective use as point of care techniques.


Subject(s)
Malaria , Point-of-Care Systems , Humans , Malaria/diagnosis , Molecular Diagnostic Techniques/methods , Nucleic Acid Amplification Techniques/methods , Prospective Studies , Sensitivity and Specificity
9.
Nucl Med Mol Imaging ; 56(3): 147-157, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35607632

ABSTRACT

Purpose: We present the findings of our final prospective study submitted to the U.S. Food and Drug Administration (FDA) for New Drug Application (NDA) approval for the use of 3,4-dihydroxy-6-[18F]fluoro-l-phenylalanine (F-18 FDOPA) positron emission tomography (PET) imaging for Parkinson's disease (PD). The primary aim was to determine the sensitivity, specificity, and predictive values of F-18 FDOPA PET in parkinsonian patients with respect to clinical standard-of-truth (SOT). Secondary outcomes included the inter-rater reliability, and correlation of quantitative measures for PET with dopaminergic status. Methods: In 68 parkinsonian subjects, F-18 FDOPA PET scan from 80 to 100 min was acquired following a CT scan. Scan images were presented to one expert in F-18 FDOPA image interpretation and two physicians with prior experience in I-123 FPCIT single-photon emission computed tomography image interpretation. Fifty-six subjects completed the study with a follow-up for SOT determination. Image readers were blind to the clinical/quantitative data; SOT clinician was blind to the image data. Results: For 47 of the 56 patients, SOT was in agreement with the PET scan results. For nine patients, SOT suggested dopaminergic deficit, whereas the imaging showed normal uptake. The specificity and positive predictive values are 91% and 92%, respectively, suggesting high probability that those who test positive by the PET scan truly have dopaminergic degeneration. The sensitivity was 73%. Inter-rater agreement was 0.6-0.8 between the different readers. Conclusion: Our prospective study demonstrates high specificity and moderate sensitivity of F-18 FDOPA PET for PD. We received NDA approval in October 2019. Supplementary Information: The online version contains supplementary material available at 10.1007/s13139-022-00748-4.

10.
Diagnostics (Basel) ; 12(1)2021 Dec 24.
Article in English | MEDLINE | ID: mdl-35054201

ABSTRACT

Isothermal techniques with lateral flow detection have emerged as a point of care (POC) technique for malaria, a major parasitic disease in tropical countries such as India. Plasmodium falciparum and Plasmodium vivax are the two most prevalent malaria species found in the country. An advanced multiplex loop-mediated isothermal amplification (mLAMP) combined with a lateral flow dipstick (LFD) technique was developed for the swift and accurate detection of P. falciparum and P. vivax, overcoming the challenges of the existing RDTs (rapid diagnostic tests). A single set of LAMP primers with a biotinylated backward inner primer (BIP primer) was used for DNA amplification of both malaria species in a single tube. The amplified DNA was hybridized with fluorescein isothiocyanate (FITC) and digoxigenin-labelled DNA probes, having a complemented sequence for the P. falciparum and P. vivax genomes, respectively. A colour band appeared on two separate LFDs for P. falciparum and P. vivax upon running the hybridized solution over them. In total, 39 clinical samples were collected from ICMR-NIMR, New Delhi. Melting curve analysis, with cross primers for both species, was used to ascertain specificity, and the sensitivity was equated with a polymerase chain reaction (PCR). The results were visualized on the LFD for both species within 60 min. We found 100% sensitivity and specificity, when compared with a traditional PCR. Melting curve analysis of mLAMP revealed the lowest detection limit of 0.15 pg/µL from sample genomic DNA. The mLAMP-LFD assays could be a potential point of care (POC) tool for early diagnosis in non-laboratory conditions, with the convenience of a reduced assay time and the simple interpretation of results.

11.
Open Biol ; 9(8): 190148, 2019 08 30.
Article in English | MEDLINE | ID: mdl-31409231

ABSTRACT

Integrins mediate the anchorage between cells and their environment, the extracellular matrix (ECM), and form transmembrane links between the ECM and the cytoskeleton, a conserved feature throughout development and morphogenesis of epithelial organs. Here, we demonstrate that integrins and components of the ECM are required during the planar cell polarity (PCP) signalling-regulated cell movement of ommatidial rotation in the Drosophila eye. The loss-of-function mutations of integrins or ECM components cause defects in rotation, with mutant clusters rotating asynchronously compared to wild-type clusters. Initially, mutant clusters tend to rotate faster, and at later stages they fail to be synchronous with their neighbours, leading to aberrant rotation angles and resulting in a disorganized ommatidial arrangement in adult eyes. We further demonstrate that integrin localization changes dynamically during the rotation process. Our data suggest that core Frizzled/PCP factors, acting through RhoA and Rho kinase, regulate the function/activity of integrins and that integrins thus contribute to the complex interaction network of PCP signalling, cell adhesion and cytoskeletal elements required for a precise and synchronous 90° rotation movement.


Subject(s)
Drosophila/embryology , Drosophila/physiology , Extracellular Matrix/metabolism , Eye/embryology , Eye/metabolism , Integrins/genetics , Signal Transduction , Animals , Body Patterning , Cell Polarity , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Eye/cytology , Gene Deletion , Gene Expression Regulation, Developmental , Immunohistochemistry , Integrins/metabolism , Models, Biological , Mutation , Protein Transport
12.
J Biol Chem ; 290(49): 29663-75, 2015 Dec 04.
Article in English | MEDLINE | ID: mdl-26451044

ABSTRACT

The Hedgehog (Hh) signaling pathway plays an essential role in vertebrate embryonic tissue patterning of many developing organs. Signaling occurs predominantly in primary cilia and is initiated by the entry of the G protein-coupled receptor (GPCR)-like protein Smoothened into cilia and culminates in gene transcription via the Gli family of transcription factors upon their nuclear entry. Here we identify an orphan GPCR, Gpr175 (also known as Tpra1 or Tpra40: transmembrane protein, adipocyte associated 1 or of 40 kDa), which also localizes to primary cilia upon Hh stimulation and positively regulates Hh signaling. Interaction experiments place Gpr175 at the level of PKA and upstream of the Gαi component of heterotrimeric G proteins, which itself localizes to cilia and can modulate Hh signaling. Gpr175 or Gαi1 depletion leads to increases in cellular cAMP levels and in Gli3 processing into its repressor form. Thus we propose that Gpr175 coupled to Gαi1 normally functions to inhibit the production of cAMP by adenylyl cyclase upon Hh stimulation, thus maximizing signaling by turning off PKA activity and hence Gli3 repressor formation. Taken together our data suggest that Gpr175 is a novel positive regulator of the Hh signaling pathway.


Subject(s)
Cyclic AMP/metabolism , Hedgehog Proteins/metabolism , Kruppel-Like Transcription Factors/metabolism , Nerve Tissue Proteins/metabolism , Receptors, G-Protein-Coupled/metabolism , 3T3 Cells , Amino Acid Sequence , Animals , COS Cells , Cell Line , Chlorocebus aethiops , Cilia/metabolism , DNA, Complementary/metabolism , Humans , Mice , Mice, Inbred C3H , Microscopy, Fluorescence , Molecular Sequence Data , RNA, Small Interfering/metabolism , Sequence Homology, Amino Acid , Signal Transduction , Smoothened Receptor , Zebrafish , Zinc Finger Protein Gli3
13.
Wiley Interdiscip Rev Dev Biol ; 1(4): 479-99, 2012.
Article in English | MEDLINE | ID: mdl-23066429

ABSTRACT

Establishment of Planar Cell Polarity (PCP) in epithelia, in the plane of an epithelium, is an important feature of the development and homeostasis of most organs. Studies in different model organisms have contributed a wealth of information regarding the mechanisms that govern PCP regulation. Genetic studies in Drosophila have identified two signaling systems, the Fz/PCP and Fat/Dachsous system, which are both required for PCP establishment in many different tissues in a largely non-redundant manner. Recent advances in vertebrate PCP studies have added novel factors of PCP regulation and also new cellular features requiring PCP-signaling input, including the positioning and orientation of the primary cilium of many epithelial cells. This review focuses mostly on several recent advances made in the Drosophila and vertebrate PCP field and integrates these within the existing PCP-signaling framework.


Subject(s)
Cell Polarity , Epithelial Cells/metabolism , Signal Transduction , Animals , Cadherins/genetics , Cadherins/metabolism , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolism , Drosophila/genetics , Drosophila/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Epithelial Cells/cytology , Frizzled Receptors/genetics , Frizzled Receptors/metabolism , Humans
14.
Dev Cell ; 23(1): 82-96, 2012 Jul 17.
Article in English | MEDLINE | ID: mdl-22814602

ABSTRACT

Drosophila Hibris (Hbs), a member of the Nephrin Immunoglobulin Super Family, has been implicated in myogenesis and eye patterning. Here, we uncover a role of Hbs in Notch (N) signaling and γ-secretase processing. Loss of hbs results in classical N-signaling-associated phenotypes in Drosophila, including eye patterning, wing margin, and sensory organ specification defects. In particular, hbs mutant larvae display altered γ-secretase-dependent Notch proteolytic processing. Hbs also interacts molecularly and genetically with Presenilin (Psn) and other components of the γ-secretase complex. This Hbs function appears conserved, as mammalian Nephrin also promotes N signaling in mammalian cells. Our data suggest that Hbs is required for Psn maturation. Consistent with its role in Psn processing, Hbs genetically interacts with the Drosophila ß-amyloid protein precursor-like (Appl) protein, the homolog of mammalian APP, the cleavage of which is associated with Alzheimer's disease. Thus, Hbs/Nephrin appear to share a general requirement in Psn/γ-secretase regulation and associated processes.


Subject(s)
Amyloid beta-Protein Precursor/metabolism , Drosophila Proteins/metabolism , Drosophila Proteins/physiology , Drosophila melanogaster/metabolism , Membrane Proteins/physiology , Presenilins/physiology , Receptors, Notch/metabolism , Amyloid beta-Protein Precursor/genetics , Animals , Drosophila Proteins/genetics , Drosophila melanogaster/embryology , Drosophila melanogaster/genetics , Genetic Association Studies , Membrane Proteins/genetics , Membrane Proteins/metabolism , Multigene Family/physiology , Multiprotein Complexes/genetics , Multiprotein Complexes/metabolism , Mutagenesis/physiology , Pedigree , Presenilins/genetics , Receptors, Notch/genetics
15.
Dev Biol ; 360(1): 132-42, 2011 Dec 01.
Article in English | MEDLINE | ID: mdl-21963539

ABSTRACT

Disheveled/Dsh proteins (Dvl in mammals) are core components of both Wnt/Wg-signaling pathways: canonical ß-catenin signaling and Frizzled (Fz)-planar cell polarity (PCP) signaling. Although Dsh is a key cytoplasmic component of both Wnt/Fz-pathways, regulation of its signaling specificity is not well understood. Dsh is phosphorylated, but the functional significance of its phosphorylation remains unclear. We have systematically investigated the phosphorylation of Dsh by combining mass-spectrometry analyses, biochemical studies, and in vivo genetic methods in Drosophila. Our approaches identified multiple phospho-residues of Dsh in vivo. Our data define three novel and unexpected conclusions: (1) strikingly and in contrast to common assumptions, all conserved serines/threonines are non-essential for Dsh function in either pathway; (2) phosphorylation of conserved Tyrosine473 in the DEP domain is critical for PCP-signaling - Dsh(Y473F) behaves like a PCP-specific allele; and (3) defects associated with the PCP specific dsh(1) allele, Dsh(K417M), located within a putative Protein Kinase C consensus site, are likely due to a post-translational modification requirement of Lys417, rather than phosphorylation nearby. In summary, our combined data indicate that while many Ser/Thr and Tyr residues are indeed phosphorylated in vivo, strikingly most of these phosphorylation events are not critical for Dsh function with the exception of DshY473.


Subject(s)
Adaptor Proteins, Signal Transducing/chemistry , Adaptor Proteins, Signal Transducing/metabolism , Drosophila Proteins/chemistry , Drosophila Proteins/metabolism , Drosophila/metabolism , Phosphoproteins/chemistry , Phosphoproteins/metabolism , Adaptor Proteins, Signal Transducing/genetics , Alleles , Amino Acid Sequence , Amino Acid Substitution , Animals , Animals, Genetically Modified , Armadillo Domain Proteins/genetics , Armadillo Domain Proteins/metabolism , Binding Sites/genetics , Cell Polarity , Dishevelled Proteins , Drosophila/genetics , Drosophila/growth & development , Drosophila Proteins/genetics , Frizzled Receptors/genetics , Frizzled Receptors/metabolism , Molecular Sequence Data , Mutagenesis, Site-Directed , Phosphoproteins/genetics , Phosphorylation , Signal Transduction , Tandem Mass Spectrometry , Transcription Factors/genetics , Transcription Factors/metabolism , Wings, Animal/growth & development , Wings, Animal/metabolism , Wnt Signaling Pathway
16.
Development ; 137(21): 3719-27, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20940230

ABSTRACT

Abl is an essential regulator of cell migration and morphogenesis in both vertebrates and invertebrates. It has long been speculated that the adaptor protein Disabled (Dab), which is a key regulator of neuronal migration in the vertebrate brain, might be a component of this signaling pathway, but this idea has been controversial. We now demonstrate that null mutations of Drosophila Dab result in phenotypes that mimic Abl mutant phenotypes, both in axon guidance and epithelial morphogenesis. The Dab mutant interacts genetically with mutations in Abl, and with mutations in the Abl accessory factors trio and enabled (ena). Genetic epistasis tests show that Dab functions upstream of Abl and ena, and, consistent with this, we show that Dab is required for the subcellular localization of these two proteins. We therefore infer that Dab is a bona fide component of the core Abl signaling pathway in Drosophila.


Subject(s)
Drosophila Proteins/genetics , Drosophila Proteins/physiology , Drosophila/embryology , Drosophila/genetics , Nerve Tissue Proteins/physiology , Protein-Tyrosine Kinases/genetics , Animals , Animals, Genetically Modified , Cell Movement/genetics , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Drosophila/physiology , Drosophila Proteins/metabolism , Embryo, Nonmammalian , Epistasis, Genetic , Female , Gene Regulatory Networks/genetics , Gene Regulatory Networks/physiology , Models, Biological , Motor Neurons/metabolism , Motor Neurons/physiology , Mutation/physiology , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Protein-Tyrosine Kinases/metabolism , Protein-Tyrosine Kinases/physiology , Signal Transduction/genetics , Signal Transduction/physiology
17.
Genes Dev ; 24(19): 2157-68, 2010 Oct 01.
Article in English | MEDLINE | ID: mdl-20837657

ABSTRACT

Abelson (Abl) family tyrosine kinases have been implicated in cell morphogenesis, adhesion, motility, and oncogenesis. Using a candidate approach for genes involved in planar cell polarity (PCP) signaling, we identified Drosophila Abl (dAbl) as a modulator of Frizzled(Fz)/PCP signaling. We demonstrate that dAbl positively regulates the Fz/Dishevelled (Dsh) PCP pathway without affecting canonical Wnt/Wg-Fz signaling. Genetic dissection suggests that Abl functions via Fz/Dsh signaling in photoreceptor R3 specification, a well-established Fz-PCP signaling readout. Molecular analysis shows that dAbl binds and phosphorylates Dsh on Tyr473 within the DEP domain. This phosphorylation event on Dsh is functionally critical, as the equivalent DshY473F mutant is nonfunctional in PCP signaling and stable membrane association, although it rescues canonical Wnt signaling. Strikingly, mouse embryonic fibroblasts (MEFs) deficient for Abl1 and Abl2/Arg genes also show reduced Dvl2 phosphorylation as compared with control MEFs, and this correlates with a change in subcellular localization of endogenous Dvl2. As in Drosophila, such Abl-deficient MEFs show no change in canonical Wnt signaling. Taken together, our results argue for a conserved role of Abl family members in the positive regulation of Dsh activity toward Fz-Dsh/PCP signaling by Dsh phosphorylation.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Cell Polarity , Drosophila Proteins/metabolism , Drosophila melanogaster , Frizzled Receptors/metabolism , Phosphoproteins/metabolism , Photoreceptor Cells, Invertebrate/cytology , Protein-Tyrosine Kinases/metabolism , Receptors, G-Protein-Coupled/metabolism , Signal Transduction , Animals , Dishevelled Proteins , Drosophila melanogaster/cytology , Drosophila melanogaster/enzymology , Phenotype , Phosphorylation , Protein Binding
18.
J Nutr ; 140(4): 786-91, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20164368

ABSTRACT

Active surveillance is an emerging management option for the rising number of men with low-grade, clinically localized prostate cancer. However, 30-40% of men on active surveillance will progress to high-grade disease over 5 y. With the ultimate aim of developing a food-based chemoprevention strategy to retard cancer progression in these otherwise healthy men, we have developed a blend of food extracts commonly consumed in Mediterranean countries and East Asia. The effect of the food extracts known as Blueberry Punch (BBP) on prostate cancer cell growth and key signaling pathways were examined in vitro and in vivo. BBP reduced prostate cancer cell growth in a dose-dependent manner (0.08-2.5%) at 72 h in vitro due to the reduction in cell proliferation and viability. Prostate cancer cell xenograft-bearing mice, administered 10% BBP in drinking water for 2 wk, had a 25% reduction in tumor volume compared with the control (water only). In vitro, BBP reduced protein concentrations in 3 signaling pathways necessary for the proliferation and survival of prostate cancer cells, namely androgen receptor, phospho-protein kinase B/protein kinase B, and phospho-cytosolic phospholipase A(2)alpha. The downstream effectors of these pathways, including prostate-specific antigen and glycogen synthase kinase 3beta, were also reduced. Thus, this palatable food supplement is a potential candidate for testing in clinical trials and may ultimately prove effective in retarding the progression of low-grade, early-stage prostate cancer in men managed by active surveillance.


Subject(s)
Group IV Phospholipases A2/metabolism , Plant Extracts/pharmacology , Prostatic Neoplasms/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Receptors, Androgen/metabolism , Analysis of Variance , Animals , Blueberry Plants/chemistry , Cell Line , Asia, Eastern , Food , Gene Expression Regulation, Neoplastic/drug effects , Humans , Male , Mediterranean Region , Mice , Mice, Nude , Plant Extracts/chemistry , Random Allocation , Signal Transduction/drug effects
19.
Clin Cancer Res ; 14(24): 8070-9, 2008 Dec 15.
Article in English | MEDLINE | ID: mdl-19088022

ABSTRACT

PURPOSE: Cytosolic phospholipase A2-alpha (cPLA2-alpha) provides intracellular arachidonic acid to supply both cyclooxygenase and lipoxygenase pathways. We aim to determine the expression and activation of cPLA2-alpha in prostate cancer cell lines and tissue and the effect of targeting cPLA2-alpha in vitro and in vivo. EXPERIMENTAL DESIGN: The expression of cPLA2-alpha was determined in prostate cancer cells by reverse transcription-PCR, Western blot, and immunocytochemistry. Growth inhibition, apoptosis, and cPLA2-alpha activity were determined after inhibition with cPLA2-alpha small interfering RNA or inhibitor (Wyeth-1). Cytosolic PLA2-alpha inhibitor or vehicle was also administered to prostate cancer xenograft mouse models. Finally, the expression of phosphorylated cPLA2-alpha was determined by immunohistochemistry in human normal, androgen-sensitive and androgen-insensitive prostate cancer specimens. RESULTS: cPLA2-alpha is present in all prostate cancer cells lines, but increased in androgen-insensitive cells. Inhibition with small interfering RNA or Wyeth-1 results in significant reductions in prostate cancer cell numbers, as a result of reduced proliferation as well as increased apoptosis, and this was also associated with a reduction in cPLA2-alpha activity. Expression of cyclin D1 and phosphorylation of Akt were also observed to decrease. Wyeth-1 inhibited PC3 xenograft growth by approximately 33% and again, also reduced cyclin D1. Immunohistochemistry of human prostate tissue revealed that phosphorylated cPLA2-alpha is increased when hormone refractory is reached. CONCLUSIONS: Expression and activation of cPLA2-alpha are increased in the androgen-insensitive cancer cell line and tissue. Inhibition of cPLA2-alpha results in cells and xenograft tumor growth inhibition and serves as a potentially effective therapy for hormone refractory prostate cancer.


Subject(s)
Cytosol/enzymology , Enzyme Inhibitors/therapeutic use , Group IV Phospholipases A2/antagonists & inhibitors , Prostatic Neoplasms/drug therapy , Apoptosis , Cell Line, Tumor , Cell Proliferation , Cyclin D1/analysis , Humans , Male , Phosphorylation , Prostatic Neoplasms/enzymology , Prostatic Neoplasms/pathology , Proto-Oncogene Proteins c-akt/metabolism
20.
Mol Cell Biochem ; 294(1-2): 163-71, 2007 Jan.
Article in English | MEDLINE | ID: mdl-16838108

ABSTRACT

Peroxisome proliferator-activated receptor gamma (PPARgamma) is a member of the nuclear receptor superfamily known to regulate adipocyte differentiation. However, its role in skeletal muscle differentiation is not known. To investigate possible involvement of PPARgamma in skeletal muscle differentiation, we modulated its expression in C2C12 mouse skeletal muscle cells by stable transfection with sense or antisense plasmid constructs of PPARgamma cDNA. Phenotypic observations and biochemical analysis of different myogenic markers showed that altered expression of PPARgamma inhibited the formation of myotubes, as well as expression of muscle-specific myogenic proteins including myogenin, MyoD and creatine kinase activity. Together, we show that critical expression of PPARgamma is required for skeletal muscle cells differentiation.


Subject(s)
Muscle Development , Muscle, Skeletal/cytology , Muscle, Skeletal/metabolism , PPAR gamma/metabolism , Animals , Cell Differentiation , Cell Line , Creatine Kinase/analysis , Creatine Kinase/metabolism , DNA, Complementary , Mice , MyoD Protein/metabolism , Myogenin/metabolism , PPAR gamma/genetics , Transfection
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