Mapping of multiple neurotransmitter receptor subtypes and distinct protein complexes to the connectome

Neurons express various combinations of neurotransmitter receptor (NR) subunits and receive inputs from multiple neuron types expressing different neurotransmitters. Localizing NR subunits to specific synaptic inputs has been challenging. Here, we use epitope-tagged endogenous NR subunits, expansion light-sheet microscopy, and electron microscopy (EM) connectomics to molecularly characterize synapses in Drosophila. We show that in directionally selective motion-sensitive neurons, different multiple NRs elaborated a highly stereotyped molecular topography with NR localized to specific domains receiving cell-type-specific inputs. Developmental studies suggested that NRs or complexes of them with other membrane proteins determine patterns of synaptic inputs. In support of this model, we identify a transmembrane protein selectively associated with a subset of spatially restricted synapses and demonstrate its requirement for synapse formation through genetic analysis. We propose that mechanisms that regulate the precise spatial distribution of NRs provide a molecular cartography specifying the patterns of synaptic connections onto dendrites.

CLSY docking to Pol IV requires a conserved domain critical for small RNA biogenesis and transposon silencing

Eukaryotes must balance the need for gene transcription by RNA polymerase II (Pol II) against the danger of mutations caused by transposable element (TE) proliferation. In plants, these gene expression and TE silencing activities are divided between different RNA polymerases. Specifically, RNA polymerase IV (Pol IV), which evolved from Pol II, transcribes TEs to generate small interfering RNAs (siRNAs) that guide DNA methylation and block TE transcription by Pol II. While the Pol IV complex is recruited to TEs via SNF2-like CLASSY (CLSY) proteins, how Pol IV partners with the CLSYs remains unknown. Here we identified a conserved CYC-YPMF motif that is specific to Pol IV and is positioned on the complex exterior. Furthermore, we found that this motif is essential for the co-purification of all four CLSYs with Pol IV, but that only one CLSY is present in any given Pol IV complex. These findings support a "one CLSY per Pol IV" model where the CYC-YPMF motif acts as a CLSY-docking site. Indeed, mutations in and around this motif phenocopy pol iv null mutants. Together, these findings provide structural and functional insights into a critical protein feature that distinguishes Pol IV from other RNA polymerases, allowing it to promote genome stability by targeting TEs for silencing.

FBXL12 degrades FANCD2 to regulate replication recovery and promote cancer cell survival under conditions of replication stress

Fanconi anemia (FA) signaling, a key genomic maintenance pathway, is activated in response to replication stress. Here, we report that phosphorylation of the pivotal pathway protein FANCD2 by CHK1 triggers its FBXL12-dependent proteasomal degradation, facilitating FANCD2 clearance at stalled replication forks. This promotes efficient DNA replication under conditions of CYCLIN E- and drug-induced replication stress. Reconstituting FANCD2-deficient fibroblasts with phosphodegron mutants failed to re-establish fork progression. In the absence of FBXL12, FANCD2 becomes trapped on chromatin, leading to replication stress and excessive DNA damage. In human cancers, FBXL12, CYCLIN E, and FA signaling are positively correlated, and FBXL12 upregulation is linked to reduced survival in patients with high CYCLIN E-expressing breast tumors. Finally, depletion of FBXL12 exacerbated oncogene-induced replication stress and sensitized cancer cells to drug-induced replication stress by WEE1 inhibition. Collectively, our results indicate that FBXL12 constitutes a vulnerability and a potential therapeutic target in CYCLIN E-overexpressing cancers.

Mapping of multiple neurotransmitter receptor subtypes and distinct protein complexes to the connectome

Neurons express different combinations of neurotransmitter receptor (NR) subunits and receive inputs from multiple neuron types expressing different neurotransmitters. Localizing NR subunits to specific synaptic inputs has been challenging. Here we use epitope tagged endogenous NR subunits, expansion light-sheet microscopy, and EM connectomics to molecularly characterize synapses in Drosophila. We show that in directionally selective motion sensitive neurons, different multiple NRs elaborated a highly stereotyped molecular topography with NR localized to specific domains receiving cell-type specific inputs. Developmental studies suggested that NRs or complexes of them with other membrane proteins determines patterns of synaptic inputs. In support of this model, we identify a transmembrane protein associated selectively with a subset of spatially restricted synapses and demonstrate through genetic analysis its requirement for synapse formation. We propose that mechanisms which regulate the precise spatial distribution of NRs provide a molecular cartography specifying the patterns of synaptic connections onto dendrites.

Analyzing Iron and Oxygen-Regulated Protein Complex Formation Using Proteomic Mass Spectrometry

Multicellular organisms have evolved elaborate strategies to sense and adapt to changes in intracellular oxygen. The canonical cellular pathway responsible for oxygen sensing consists of the von Hippel-Lindau (pVHL) tumor suppressor protein, prolyl hydroxylases (PHD), and hypoxia-inducible factors (HIFs), which together regulate expression of downstream genes involved in oxygen homeostasis. In recent years, it has become increasingly clear that oxygen regulatory mechanisms are intertwined with cellular iron-sensing pathways. Key members of these networks such as prolyl-hydroxylases, E3 ubiquitin ligase adaptor protein FBXL5, iron regulatory proteins (IRPs), and Fe-S cluster proteins require both iron and oxygen for their optimal function and/or are tightly regulated by intracellular concentrations of these molecules. Monitoring how protein interactomes are remodeled as a function of intracellular oxygen and iron levels gives insights into the nature and dynamics of these pathways. We have recently described an oxygen-sensitive interaction between FBXL5 and the cytoplasmic Fe-S cluster targeting complex (CIA targeting complex) with implications in the FBXL5-dependent regulation of IRPs. Based on this work, we present a protocol describing the induction and maintenance of hypoxia in mammalian cell cultures and a mass-spectrometry-based proteomics approach aimed at interrogating changes in interactome of key proteins as a function of intracellular oxygen and iron levels. These methods are widely applicable to understanding the dynamics of iron and oxygen signaling.

Piezosurgery Versus Conventional Method Alveoloplasty: A Comparative Study

Purpose

The conventional alveoloplasty approach which uses manual equipment results in more resorption of the underlying alveolar ridge that makes denture prosthesis unstable. The goal of this study was to compare results of piezosurgery alveoloplasty to those of conventional alveoloplasty.

Materials and Methods

This was an in-vivo comparative study consisting of ten edentulous individuals who needed alveoloplasty due to bilateral bony projection. On one side, a conventional alveoloplasty was performed with a bone rongeur and bone file, whereas the contralateral side was treated with a piezosurgery unit. The clinical parameters were analyzed using SPSS version 21 software including operating time, postoperative pain evaluation on day 3 and a healing on day 7.

Results

There was a statistically significant difference between the two groups in terms of outcome variables such as operating time, pain and healing. The Conventional group has a lower mean of operating time, a higher mean rank of VAS and a lower mean rank of healing index compared to the piezosurgery group.

Conclusion

Piezosurgery alveoloplasty not only lowers postoperative patient discomfort but also preserves alveolar bone integrity by not disrupting soft and hard tissue architecture thus allowing faster tissue healing and easier prosthesis replacement in the future.

First Leptophobic Dark Matter Search from the Coherent-CAPTAIN-Mills Liquid Argon Detector

We report the first results of a search for leptophobic dark matter (DM) from the Coherent-CAPTAIN-Mills (CCM) liquid argon (LAr) detector. An engineering run with 120 photomultiplier tubes (PMTs) and 17.9×10^{20} protons on target (POT) was performed in fall 2019 to study the characteristics of the CCM detector. The operation of this 10-ton detector was strictly light based with a threshold of 50 keV and used coherent elastic scattering off argon nuclei to detect DM. Despite only 1.5 months of accumulated luminosity, contaminated LAr, and nonoptimized shielding, CCM's first engineering run has already achieved sensitivity to previously unexplored parameter space of light dark matter models with a baryonic vector portal. With an expected background of 115 005 events, we observe 115 005+16.5 events which is compatible with background expectations. For a benchmark mediator-to-DM mass ratio of m_{V_{B}}/m_{χ}=2.1, DM masses within the range 9  MeV≲m_{χ}≲50  MeV are excluded at 90% C. L. in the leptophobic model after applying the Feldman-Cousins test statistic. CCM's upgraded run with 200 PMTs, filtered LAr, improved shielding, and 10 times more POT will be able to exclude the remaining thermal relic density parameter space of this model, as well as probe new parameter space of other leptophobic DM models.

Iron-regulated assembly of the cytosolic iron-sulfur cluster biogenesis machinery

The cytosolic iron–sulfur (Fe-S) cluster assembly (CIA) pathway delivers Fe-S clusters to nuclear and cytosolic Fe-S proteins involved in essential cellular functions. Although the delivery process is regulated by the availability of iron and oxygen, it remains unclear how CIA components orchestrate the cluster transfer under varying cellular environments. Here, we utilized a targeted proteomics assay for monitoring CIA factors and substrates to characterize the CIA machinery. We find that nucleotide-binding protein 1 (NUBP1/NBP35), cytosolic iron–sulfur assembly component 3 (CIAO3/NARFL), and CIA substrates associate with nucleotide-binding protein 2 (NUBP2/CFD1), a component of the CIA scaffold complex. NUBP2 also weakly associates with the CIA targeting complex (MMS19, CIAO1, and CIAO2B) indicating the possible existence of a higher order complex. Interactions between CIAO3 and the CIA scaffold complex are strengthened upon iron supplementation or low oxygen tension, while iron chelation and reactive oxygen species weaken CIAO3 interactions with CIA components. We further demonstrate that CIAO3 mutants defective in Fe-S cluster binding fail to integrate into the higher order complexes. However, these mutants exhibit stronger associations with CIA substrates under conditions in which the association with the CIA targeting complex is reduced suggesting that CIAO3 and CIA substrates may associate in complexes independently of the CIA targeting complex. Together, our data suggest that CIA components potentially form a metabolon whose assembly is regulated by environmental cues and requires Fe-S cluster incorporation in CIAO3. These findings provide additional evidence that the CIA pathway adapts to changes in cellular environment through complex reorganization.

Measurement of the Nucleon F_{2}^{n}/F_{2}^{p} Structure Function Ratio by the Jefferson Lab MARATHON Tritium/Helium-3 Deep Inelastic Scattering Experiment

The ratio of the nucleon F_{2} structure functions, F_{2}^{n}/F_{2}^{p}, is determined by the MARATHON experiment from measurements of deep inelastic scattering of electrons from ^{3}H and ^{3}He nuclei. The experiment was performed in the Hall A Facility of Jefferson Lab using two high-resolution spectrometers for electron detection, and a cryogenic target system which included a low-activity tritium cell. The data analysis used a novel technique exploiting the mirror symmetry of the two nuclei, which essentially eliminates many theoretical uncertainties in the extraction of the ratio. The results, which cover the Bjorken scaling variable range 0.19<x<0.83, represent a significant improvement compared to previous SLAC and Jefferson Lab measurements for the ratio. They are compared to recent theoretical calculations and empirical determinations of the F_{2}^{n}/F_{2}^{p} ratio.

Cosmic Ray Background Removal With Deep Neural Networks in SBND

In liquid argon time projection chambers exposed to neutrino beams and running on or near surface levels, cosmic muons, and other cosmic particles are incident on the detectors while a single neutrino-induced event is being recorded. In practice, this means that data from surface liquid argon time projection chambers will be dominated by cosmic particles, both as a source of event triggers and as the majority of the particle count in true neutrino-triggered events. In this work, we demonstrate a novel application of deep learning techniques to remove these background particles by applying deep learning on full detector images from the SBND detector, the near detector in the Fermilab Short-Baseline Neutrino Program. We use this technique to identify, on a pixel-by-pixel level, whether recorded activity originated from cosmic particles or neutrino interactions.

A Robust Method for Packing High Resolution C18 RP-nano-HPLC Columns

The high complexity prevalent in biological samples requires chromatographic separations with high sensitivity and resolution to be effectively analyzed. Here we introduce a robust, reproducible and inexpensive protocol for preparation of a nano-flow reversed phase high performance liquid chromatography (RP-HPLC) columns for on-line separation of analytical peptides before introduction into and detection by a mass-spectrometer in traditional bottom-up proteomics workflows. Depending on the goal of the experiment and the chemical properties of the analytes being separated, optimal column parameters may differ in their internal or outer diameters, length, particle size, pore size, chemistry of stationary phase particles, and the presence or absence of an integrated electrospray emitter at the tip. An in-house column packing system not only enables the rapid fabrication of columns with the desired properties but also dramatically reduces the cost of the process. The optimized protocol for packing a C18 AQ (aqueous) fused silica column discussed here is compatible with a wide range of liquid chromatographic instruments for achieving effective separation of analytes.

Enhanced Dispersion and Mechanical Behavior of Polypropylene Composites Compounded Using Extension-Dominated Extrusion

The process of dispersing filler in polymer matrix is vital to the behavior of polymer composites. The current study involves understanding the extent of dispersion of filler by only varying the nature of mixing during the process. Identical polymer composite materials are processed via two different kinds of mixing sections on the screw in a twin-screw extruder, differing in the type and amount of stress they impose on the filler agglomerate. An aggressive (900) Kneading Block (KB) mixing section is compared with recently developed Extensional Mixing Elements (EMEs), which impart extension dominated mixing while KB imparts shear dominated mixing. Various EME geometries of different levels of aggressiveness were computationally studied and validated. Composites obtained from KB are compared with composites processed using five different EME geometries. Three composites of Polypropylene (PP) filled with carbon black, graphene nano platelets and carbon nanotubes were studied independently. Composites processed through EMEs display about an order of magnitude better dispersion of filler agglomerate over the composites processed through KB. In addition, enhanced modulus and yield stress is observed for composites processed through EMEs. An improvement of 63% to 266% in the strain achieved for EME processed composites is seen under biaxial film stretching.

AB0713 PERIODONTAL DISEASES AND ITS ASSOCIATION WITH ANKYLOSING SPONDYLITIS/SPA: A SYSTEMATIC REVIEW

Background:

A close association between periodontal disease and Ankylosing spondylitis (AS) has long been specualted. Both diseases are characterized by dysregulation of the host inflammatory response, leading to further destruction of soft and hard connective tissue with there being evidence of increased levels of TNF-α and various interleukins in both patients of AS and periodontitis.

Objectives:

The aim of this systematic review was to appraise the available literature exploring the relationship between AS and periodontal disease.

Methods:

We searched Medline & Embase databases (from their inception till October 2019) using appropriate combinations of following search items with limits ‘(English, Human)’; Ankylosing spondylitis, spondyloarthritis, spondyloarthropathies, spondyloarthritides, spinal disease, musculoskeletal disease, Rheumatic disease AND periodontitis, periodontal disease, periodontoses, parodontoses, chronic periodontitis, gum disease, gingivitis, oral health, dental health, plaque index, bleeding on probing, probing pocket depth, clinical attachment loss. This search was supplemented by the manual search of bibliographies of articles selected and conferences proceedings of EULAR. Only be reviews, observational study of cross-sectional, cohort or case control type on adult patients with AS were selected. Data was extracted from a predesigned proforma. A close association between periodontal disease and Ankylosing spondylitis (AS) has long been specualted. Both diseases are characterized by dysregulation of the host inflammatory response, leading to further destruction of soft and hard connective tissue with there being evidence of increased levels of TNF-α and various interleukins in both patients of AS and periodontitis.

Results:

A total number of 984 articles were identified and 12 were selcted for detailed appraisal (Figure 1, PRISMA flow chart). They were all case control studies. The prevalence of periodontitis ranged from 38% to 88% in patients with AS whereas in the control group from 26% to 71 % in controls. Out of 12 studies, two showed significant changes in Plaque Index (PI), two studies showed altered Pocket Probing Depth (PPD), three showed significant increased in Clinical Attachment Loss (CAL) and increased Bleeding On Probing (BOP) was seen in 2 studies. In 7 studies, periodontitis was seen in a significant number of patients with AS (P<0.05). All studies reported that the prevalence of periodontal disease in AS patients was higher as compared to non-AS patients.

Conclusion:

Our systematic review found an association between AS and periodontal disease. Patients with AS show higher prevalence of periodontitis and a poor oral hygiene as compared to healthy controls. At practice level, this systematic review underscores the need for a collaboration between dentists and rheumatologist.

Disclosure of Interests:

None declared

Probing Few-Body Nuclear Dynamics via ^{3}H and ^{3}He (e,e^{'}p)pn Cross-Section Measurements

We report the first measurement of the (e,e^{'}p) three-body breakup reaction cross sections in helium-3 (^{3}He) and tritium (^{3}H) at large momentum transfer [⟨Q^{2}⟩≈1.9  (GeV/c)^{2}] and x_{B}>1 kinematics, where the cross section should be sensitive to quasielastic (QE) scattering from single nucleons. The data cover missing momenta 40≤p_{miss}≤500  MeV/c that, in the QE limit with no rescattering, equals the initial momentum of the probed nucleon. The measured cross sections are compared with state-of-the-art ab initio calculations. Overall good agreement, within ±20%, is observed between data and calculations for the full p_{miss} range for ^{3}H and for 100≤p_{miss}≤350  MeV/c for ^{3}He. Including the effects of rescattering of the outgoing nucleon improves agreement with the data at p_{miss}>250  MeV/c and suggests contributions from charge-exchange (SCX) rescattering. The isoscalar sum of ^{3}He plus ^{3}H, which is largely insensitive to SCX, is described by calculations to within the accuracy of the data over the entire p_{miss} range. This validates current models of the ground state of the three-nucleon system up to very high initial nucleon momenta of 500  MeV/c.

Development of a biomarker of efficacy in second-line treatment for lymphangioma of the tongue: a pilot study

Lymphangioma of the tongue is a rare lymphatic malformation, and various authors have reported the successful use of sirolimus for its treatment. However, the safety of sirolimus in children needs further evaluation so that those who do not respond are not necessarily exposed to its potential adverse effects. We hypothesised that assessment of lymphangiogenesis can be used to predict whether the patient will respond to sirolimus, so we organised a prospective study after ethics committee approval had been given. After clinical and histological diagnoses of lymphangioma of the tongue had been confirmed, 16 patients were given sirolimus 0.8mg/day in three divided doses. Clinical response was assessed and compared with lymphatic microvessel density (LMVD), which was calculated immunohistochemically using the monoclonal antibody D2-40 as the lymphatic endothelial marker. Nine patients responded well, five partially, and two failed to respond. Mean (SD) LVD among the good responders was 21.00 (3.74), whereas among non-responders it was 8.00 (4.24). There was a significant difference in mean LVD between good responders, partial responders, and non-responders (p=0.04). Sirolimus is effective in treating children with lymphangioma of the tongue, and lymphangiogenesis is a useful therapeutic predictive marker.

First Measurement of Inclusive Muon Neutrino Charged Current Differential Cross Sections on Argon at E_{ν}∼0.8 GeV with the MicroBooNE Detector

We report the first measurement of the double-differential and total muon neutrino charged current inclusive cross sections on argon at a mean neutrino energy of 0.8 GeV. Data were collected using the MicroBooNE liquid argon time projection chamber located in the Fermilab Booster neutrino beam and correspond to 1.6×10^{20} protons on target of exposure. The measured differential cross sections are presented as a function of muon momentum, using multiple Coulomb scattering as a momentum measurement technique, and the muon angle with respect to the beam direction. We compare the measured cross sections to multiple neutrino event generators and find better agreement with those containing more complete treatment of quasielastic scattering processes at low Q^{2}. The total flux integrated cross section is measured to be 0.693±0.010(stat)±0.165(syst)×10^{-38}  cm^{2}.

Electron versus Muon Neutrino Induced Cross Sections in Charged Current Quasielastic Processes

Differences between ν_{e} and ν_{μ} quasielastic cross sections are essential in neutrino oscillation analyses and CP violation searches for experiments such as DUNE and T2HK. The ratio of these is however poorly known experimentally and for certain kinematic regions theoretical models give contradictory answers. We use two independent mean-field based models to investigate this ratio using ^{40}Ar and ^{12}C targets. We demonstrate that a proper treatment of the final nucleon's wave function confirms the dominance of ν_{μ} over ν_{e} induced cross sections at forward lepton scattering.

An Oxygen-Dependent Interaction between FBXL5 and the CIA-Targeting Complex Regulates Iron Homeostasis

The iron-sensing protein FBXL5 is the substrate adaptor for a SKP1-CUL1-RBX1 E3 ubiquitin ligase complex that regulates the degradation of iron regulatory proteins (IRPs). Here, we describe a mechanism of FBXL5 regulation involving its interaction with the cytosolic Fe-S cluster assembly (CIA) targeting complex composed of MMS19, FAM96B, and CIAO1. We demonstrate that the CIA-targeting complex promotes the ability of FBXL5 to degrade IRPs. In addition, the FBXL5-CIA-targeting complex interaction is regulated by oxygen (O₂) tension displaying a robust association in 21% O₂ that is severely diminished in 1% O₂ and contributes to O₂-dependent regulation of IRP degradation. Together, these data identify a novel oxygen-dependent signaling axis that links IRP-dependent iron homeostasis with the Fe-S cluster assembly machinery.

Comparative evaluation of dexmedetomidine and labetalol for attenuating hemodynamic stress responses during laparoscopic cholecystectomy in borderline hypertensive patients

OBJECTIVE

Various pharmacological agents have been tried to attenuate the pressor response in laparoscopic cholecystectomy patients. We have compared single pre-induction intravenous injection of dexmedetomidine with labetalol for attenuation of haemodynamic stress response.

METHODS

A total of 160 patients were considered for this prospective, randomized, double blind clinical study done in a single tertiary care institution. Patients were either included in group D, to receive 1.0μg·kg^-1 i.v. dexmedetomidine or group L, to receive 0.3 mg·kg^-1 i.v. labetalol in 100ml of normal saline before induction of anaesthesia. Patient's hemodynamic parameters were noted pre-operatively before starting infusion and at fixed intervals afterwards till extrubation.

RESULTS

After intubation, mean systolic blood pressure (SBP) was higher in patients of group L (128.0 ± 13.866) as compared to group D (123.2 ± 10.672). Afterwards the SBP was comparable until extrubation. Similarly, after intubation patients in group D tended to have lower diastolic pressure (73.1 ± 9.683 vs. 79.2± 14.153, P value .0017) compared to patients in group L. Also, the relative incidence of bradycardia and hypotension was higher in patients who had received inj. labetalol.

CONCLUSION

In patients predisposed to significant fluctuations in blood pressure or heart rate dexmedetomidine may be more suitable than labetalol due to better preservation of normal haemodynamics especially during periods of stress showing a relatively lower incidence of side effects.

Characterizing the hypertolerance potential of two indigenous bacterial strains (Bacillus flexus and Acinetobacter junii) and their efficacy in arsenic bioremediation

AIMS

The aims of the study were to (i) isolate and characterize arsenic-tolerant bacterial strains, (ii) study the plant growth-promoting traits and (iii) explore their bioremediation potential.

METHODS AND RESULTS

Indigenous arsenic hypertolerant bacterial isolates NM02 and NM03 were screened as they were capable of growing at 150 mmol l^-1 As (V) and 70 mmol l^-1 As (III). They were identified on the basis of morphological, physiological and biochemical parameter and 16sDNA sequence as Bacillus flexus and Acinetobacter junii respectively. Genomic DNA analysis for the investigation of ars operon revealed the presence of metalloregulatory arsC gene, suggesting their ability to detoxify arsenic. The analysis for siderophore, phosphate solubilization, indole acetic acid (IAA) and ACC deaminase highlighted the intrinsic plant growth-promoting rhizobacteria traits of both the bacterial strains. The energy dispersive spectroscopy analysis proved the potential of cellular arsenic sequestration within the strains. Moreover, Fourier-transform infrared spectra revealed the repositioning of the spectral bands in As presence, indicating the presence of those functional groups on the bacterial surface that is involved in As adsorption.

CONCLUSIONS

Our results indicate that bacterial strains NM02 and NM03 were identified as potent applicants for arsenic bioremediation and possess the ability to facilitate plant growth.

SIGNIFICANCE AND IMPACT OF THE STUDY

The bacterial strains are proficient in As detoxification and can be employed for arsenic bioremediation; a cost-effective and in situ remediation technique for the polluted soil.

Abstract P2-06-12: Oncogenic potential of Trefoil factor 3 in initiation of mammary carcinoma through suppression of p53 pathway

Background

Oncogenic transformation is a complex multistep process where normal cells acquire the hallmarks of cancer, leading to unrestrained outgrowth of malignant clones. Trefoil Factor 3 (TFF3) is a clinically validated and functionally potent oncogene in mammary carcinoma. Elevated TFF3 expression has been consistently observed in mammary carcinoma, being involved in cancer progression. The present study investigates the potential functional role and the underlying mechanisms of TFF3 in promoting oncogenic transformation early in the onset of mammary carcinoma.

Material and method

Immortalized human mammary epithelial cells (HMECs): HMEC-hTERT, MCF10A and MCF12A, with forced expression of TFF3, were used as in vitro models and in an orthotopic xenograft model to study the oncogenic roles of TFF3. Furthermore, microarray analysis, immunofluorescence, and ubiquitination and CHX chase assays were used to examine the involvement of p53 pathway in TFF3 mediated-oncogenic transformation.

Results

Immortalized HMECs with forced expression of TFF3 exhibited the capacity of anchorage independent growth in the soft agar colony formation assay, which is a hallmark of oncogenic transformation. The forced expression of TFF3 also enhanced 3D growth of the immortalized HMECs in matrigel. Furthermore, immortalized HMECs with forced expression of TFF3 gaverise to orthotopic xenograft tumors in nude mice, which are not observed in mice injected with immortalized HMECs. These observations suggest that TFF3 stimulates the oncogenic transformation of non-malignant immortalized HMECs. In addition, the forced expression of TFF3 promoted aberrant cell proliferation, resistance to apoptosis, and increased cell migration and invasion of the HMECs, all these being important hallmarks of cancer. Here, we showed that TFF3-mediated oncogenic transformation of the immortalized HMEC-hTERT cells is dependent on p53 signaling pathway suppression. Mechanistically, TFF3 downregulated NF-κB (p65)-mediated transcription of p53 through decreasing NF-κB (p65) expression and nuclear accumulation. TFF3 also decreased p53 protein levels through post-transcriptional regulation. The forced expression of TFF3 increased MDM2 expression, resulting in an increased ubiquitin-mediated proteasomal degradation of p53. Moreover, forced expression of TFF3 decreased the cleaved form of MDM2, which is responsible for stabilizing p53 protein. Concordantly, HMECs with forced expression of TFF3 exhibited shorter p53 protein half-life as compared to vector control HMECs .

Conclusion

In summary, our study highlights the oncogenic potential of TFF3 in the initiation of mammary carcinoma through the suppression of the p53 pathway.

Citation Format: Chen RM, Pandey V, Chong QY, Poh HM, Zhang MY, Kumar AP, Lobie PE. Oncogenic potential of Trefoil factor 3 in initiation of mammary carcinoma through suppression of p53 pathway [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-06-12.

Abstract P6-20-09: Pharmacological inhibition of TFF3 enhances chemo-sensitivity and overcomes acquired resistance in breast cancer

Background

Dose-dependent toxicity and acquired chemo-resistance are two major challenges in the use of doxorubicin in breast cancer treatment. Trefoil factor 3 (TFF3) is a secreted ligand that promotes breast cancer progression and predicts poor survival outcome of breast cancer patients. It has also been shown to confer resistance to anti-estrogens and trastuzumab in breast cancer. Here, the role of TFF3 in regulating the sensitivity and acquired resistance to doxorubicin in breast cancer was investigated.

Methods

MCF7, ZR-75-1 and BT474 breast cancer cell lines with siRNA-mediated depletion of TFF3, and doxorubicin-resistant MCF7 cells generated from the pulsatile exposure to doxorubicin, were used as in vitromodels. We have developed a novel non-toxic small molecule inhibitor of TFF3 (AMPC) that binds specifically to cysteine 57 residue of dimeric TFF3 and promotes its dissociation to monomers thereby, inhibiting its dimeric functions such as proliferation and apoptosis. Here, the effects of AMPC in enhancing doxorubicin sensitivity and overcoming acquired doxorubicin resistance in breast cancer cells were also explored.

Results

Consistent with siRNA-mediated depletion of TFF3, pharmacological inhibition of TFF3 by AMPC enhanced doxorubicin-mediated decrease in cell viability, foci formation and 3D growth of the breast cancer cells, suggesting that TFF3 inhibition increased the sensitivity of these cells to doxorubicin treatment. Notably, AMPC combined with doxorubicin in a synergistic manner, enabling doxorubicin dose reduction for the same inhibitory effect. Doxorubicin-induced AKT activation has been reported to antagonize the effects of doxorubicin and promote its resistance in breast cancer. Here, the inhibition of TFF3 by AMPC was shown to reduce AKT activation. Mechanistically, AMPC co-treatment suppressed doxorubicin-induced AKT activation thereby enhancing doxorubicin-induced apoptosis, with an overall up-regulation of pro-apoptotic and down-regulation of anti-apoptotic proteins, as compared to doxorubicin monotherapy. TFF3 also mediated the acquired doxorubicin resistance in MCF7 cells. Elevated expression of TFF3 was observed in the doxorubicin-resistant MCF7 cells as compared to the parental MCF7 cells, while the inhibition of TFF3 by AMPC completely abrogated the resistant phenotype of these cells as shown in the cell viability, foci formation and 3D growth assays. In concordance with the elevated levels of TFF3, doxorubicin-resistant MCF7 cells also exhibited increased activation of AKT with reduced susceptibility to doxorubicin-induced apoptosis as compared to the parental MCF7 cells. Consistently, this was reversed with AMPC co-treatment, which suppressed the elevated levels of activated AKT in the doxorubicin-resistant MCF7 cells, resulting in the re-sensitization of these resistant cells to doxorubicin-induced apoptosis. Similar to that in the parental cells, AMPC also exhibited a synergistic inhibitory effect with doxorubicin in the doxorubicin-resistant MCF7 cells.

Conclusion

The pharmacological inhibition of TFF3 with AMPC is a potential therapeutic approach to reduce the dose-dependent toxicity and to overcome the acquired resistance of doxorubicin in breast cancer.

Citation Format: Poh HM, Chong QY, Chen RM, Pandey V, Salundi B, Kumar AP, Lee SC, Lobie PE. Pharmacological inhibition of TFF3 enhances chemo-sensitivity and overcomes acquired resistance in breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-20-09.

Role of intralesional bleomycin and intralesional triamcinolone therapy in residual haemangioma following propranolol

With the emergence of propranolol as the first choice of treatment for problematic infantile haemangioma at many centres, the number of patients with a partial or non-response to propranolol has also been growing. This study investigated the role of intralesional bleomycin and triamcinolone in patients with residual disease following propranolol therapy for infantile haemangioma. Sixty-seven patients with residual haemangioma were assigned randomly to receive either intralesional bleomycin (group A, n=36) or intralesional triamcinolone (group B, n=31). The response to treatment and adverse effects were assessed in both groups. All patients received at least four doses and a maximum of six doses of the assigned drug. In group A (mean follow-up 9.38months), 47.2% had an excellent response and 44.4% a good response. In group B (mean follow-up 7.42months), 25.8% had an excellent response and 48.4% a good response. There was no difference in overall response between the groups (P=0.074). Among patients who were initially non-responders to propranolol, bleomycin showed a better response than triamcinolone (P=0.037). This may be due to an overlap in the mechanism of action of propranolol and triamcinolone. Thus, intralesional bleomycin should be preferred in patients with no initial response to propranolol therapy, while bleomycin or triamcinolone can be used in patients with a partial response to propranolol therapy, as they have equal efficacy.

Stimulation of ribosomal RNA gene promoter by transcription factor Sp1 involves active DNA demethylation by Gadd45-NER pathway

The well-studied Pol II transcription factor Sp1 has not been investigated for its regulatory role in rDNA transcription. Here, we show that Sp1 bound to specific sites on rDNA and localized into the nucleoli during the G1 phase of cell cycle to activate rDNA transcription. It facilitated the recruitment of Pol I pre-initiation complex and impeded the binding of nucleolar remodeling complex (NoRC) to rDNA resulting in the formation of euchromatin active state. More importantly, Sp1 also orchestrated the site-specific binding of Gadd45a-nucleotide excision repair (NER) complex resulting in active demethylation and transcriptional activation of rDNA. Interestingly, knockdown of Sp1 impaired rDNA transcription due to reduced engagement of the Gadd45a-NER complex and hypermethylation of rDNA. Thus, the present study unveils a novel role of Sp1 in rDNA transcription involving promoter demethylation.

Abstract P4-04-12: Enhancing the immunogenicity of breast cancer cells to stimulate innate immunity and augment the effects of cellular immunotherapy

A promising strategy for treating metastatic breast cancer is engaging the immune system to destroy disseminated breast cancer cells. However, breast cancer is a challenge for immunotherapy because of its inherent genetic heterogeneity and decreased immunogenicity. There is an unmet need to develop new, targeted therapies for breast cancer that stimulate the immune system and can be used in combination with checkpoint blockade or adoptive cell transfer to fight metastatic disease. One potential approach is to generate dying breast cancer cells that operate like a vaccine to stimulate a tumor-specific immune response. This is termed immunogenic cell death (ICD) and is characterized by a unique molecular signature, involving the release of molecules that attract and stimulate phagocytes like dendritic cells (DCs) and that could sensitize tumor cells to killing by natural killer (NK) cells. With the discovery of new ICD-inducing agents, interest in this approach is increasing. However, the current doses of drugs used to induce ICD may be too high to translate into clinically relevant regimens. To address these problems, our group developed a novel cytotoxic peptide, CT20p, and a nanotechnology-based platform to deliver and concentrate CT20p in breast tumors. We found that treatment of a murine xenograft model with nanomolar amounts of CT20p, encapsulated in nanoparticles formed with a novel hyperbranched polyester polymer (HBPE-NPs), resulted in regression of breast cancer tumors, and that dying breast cancer cells expressed markers characteristic of ICD, such as the pre-mortem exposure of the "eat me" signal, calreticulin (Crt). The intracellular target of CT20p is a protein called chaperonin-containing T-complex (CCT), which is essential for the folding of actin and tubulin and other critical proteins into their native forms. Disruption of CCT could cause endoplasmic reticulum (ER) stress through the accumulation of misfolded proteins. ER stress in turn initiates intracellular pathways that generate the danger signals associate with ICD. To this end, we observed that cancer cells treated with CT20p displayed alterations in PERK, a key mediator of the unfolded protein response (UPR) and translocation of Crt. As a result, CT20p-treated cancer cells were more readily phagocytosed. More importantly, NK cells more effectively killed cancer cells pre-treated with CT20p. This suggests that CT20p may stimulate NK cell cytotoxicity by inducing activating signals on cancer cells, which would greatly augment the curative effects of adoptive transfer of NK cells. In our experiments normal breast epithelial cells, macrophages or NK cells, themselves, were unaffected by CT20p treatment due reduced CCT. These studies indicate that a single molecule, CT20p, can do both the killing of cancer cells and activation of immune cells and can be combined with cellular immunotherapy (e.g. expanded NK cells) to provide a more complete protection from breast cancer recurrence and metastasis.

Citation Format: Khaled AR, Limaye A, Bassiouni R, Showalter A, Oyer J, Pandey V, Igarashi R, Altomare DA, Copik AJ. Enhancing the immunogenicity of breast cancer cells to stimulate innate immunity and augment the effects of cellular immunotherapy. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-04-12.

Association of oxidative status and semen characteristics with seminal plasma proteins of buffalo semen

To study the influence of season on oxidative status of buffalo semen and their association with semen characteristics and seminal plasma proteins, ejaculates were collected twice a week in winter, summer and rainy seasons from six adult Bhadawari buffalo bulls. The neat semen was analyzed for semen characteristics immediately after collection and oxidative status viz. lipid peroxidation (LPO), catalase (CAT), super oxide dismutase (SOD) activity, and total protein (TP) were estimated in seminal plasma. The protein profiling was carried out by one-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The significant effect of season was observed on TP, SOD activity and % protein fractions of seminal plasma proteins of buffalo bulls. The TP values showed positive correlation with ejaculate volume (EV), sperm concentration (SC), and % live-dead (LD) and negative correlation with progressive motility (PM), and hypo-osmotic swelling test (HOST). The SOD activity showed positive correlation with PM, LD, HOST and % acrosoamal integrity (AI). Besides that, results showed correlation of TP with 6.5, 38 and 66 kDa proteins, LPO with 70, 72, 84 and 86 kDa proteins, CAT with 70 kDa and 86 kDa proteins, and SOD with 6.5, 24.5, 44.5, 70 and 72 kDa proteins. In conclusion, this study indicated that TP and SOD activity of seminal plasma of buffalo bulls were influenced by season and were found to be associated with some of the semen characteristics and expression of seminal plasma proteins.

The "Macro" World of microRNAs in Hepatocellular Carcinoma

Hepatotropic viruses such as hepatitis B virus (HBV) and hepatitis C virus (HCV) are the major etiological agents associated with development of hepatocellular carcinoma (HCC). Progression of HCC is a multistep process that requires sequential or parallel deregulation of oncogenic and tumor suppressive pathways leading to chromosomal instability and neoplastic phenotype. In the recent years, microRNAs (miRNAs) have carved their own niche alongside oncogenes and tumor suppressors, owing to their innate ability to receive and relay multiple signals. Not surprisingly, miRNAs are fast emerging as central player in myriads of malignancies including HCC. miRNAs are reported to participate in initiation and progression of HCC, and have also been clinically correlated with risk assessment, disease grade, aggressiveness, and prognosis. Despite extensive data available on the role of miRNAs in HCC, there is a pressing need to integrate and evaluate these datasets to find its correlation, if any, with causal agents in order to devise novel interventional modalities. Through this review, we attempt to bridge the gap by consolidating the current knowledge and concepts in the field of HCC-related miRNAs with special emphasis on HBV and HCV. Further, we assess the potential of common as well as unique signatures that may be useful in developing novel biomarkers and therapeutics.

Charcot's Elbow Following Syringomyelia: Revisited

Neuropathic arthropathy of the elbow joint is uncommon with a reported incidence of 3-8%only. The natural history, pathogenesis and management approaches are debatable with an absence of clear guidelines. We report two cases of Charcot's elbow following syringomyelia with ulnar nerve manifestations. One patient required debulkingsynovectomy and ulnar nerve decompression while the other was managed conservatively. The article aims to enrich the limited knowledge of managing Charcot's elbow.

Impacts of increasing ozone on Indian plants

Increasing anthropogenic and biogenic emissions of precursor compounds have led to high tropospheric ozone concentrations in India particularly in Indo-Gangetic Plains, which is the most fertile and cultivated area of this rapidly developing country. Current ozone risk models, based on European and North American data, provide inaccurate estimations for crop losses in India. During the past decade, several ozone experiments have been conducted with the most important Indian crop species (e.g. wheat, rice, mustard, mung bean). Experimental work started in natural field conditions around Varanasi area in early 2000's, and the use of open top chambers and EDU (ethylene diurea) applications has now facilitated more advanced studies e.g. for intra-species sensitivity screening and mechanisms of tolerance. In this review, we identify and discuss the most important gaps of knowledge and future needs of action, e.g. more systematic nationwide monitoring for precursor and ozone formation over Indian region.

Trefoil factor 1 suppression of E-CADHERIN enhances prostate carcinoma cell invasiveness and metastasis

Metastasis is the primary mediator of prostate cancer (PCA) lethality and poses a significant clinical obstacle. The identification of factors involved in the metastasis of PCA is imperative. We demonstrate herein that trefoil factor 1 (TFF1) promotes PCA cell migration and invasion in vitro and metastasis in vivo. The capacity of TFF1 to enhance cell migration/invasion is mediated by transcriptional repression of E-CADHERIN. Consideration of targeted inhibition of TFF1 to prevent metastasis of prostate carcinoma is warranted.

Physiological effects of arsenate on transplant thalli of the lichen Pyxine cocoes (Sw.) Nyl

INTRODUCTION

The changes in photosynthetic pigments, chlorophyll fluorescence, protein content, and antioxidant enzymes were investigated in a foliose lichen Pyxine cocoes, which was subjected to increasing concentrations of arsenate.

METHODS

The arsenate concentrations of 10, 25, 50, 75, 100, and 200 μM were sprayed every alternate day on the lichen thallus. The thalli were then harvested on 10, 20, 30, and 45 days.

RESULTS

The quantity of photosynthetic pigments exhibited a decreasing trend till 20 days but increased from 30 days onwards. Concomitantly, chlorophyll fluorescence also showed a decreasing trend with increasing arsenic treatment duration as well as concentration. The higher concentration of arsenate was found to be deleterious to the photosynthesis of lichen as the chlorophyll fluorescence and the amount of pigments decreased significantly. The protein content of lichen increased uninterruptedly as the concentration of arsenate as well as duration of treatment increased. The activities of superoxide dismutase and ascorbate peroxide increased initially at lower concentration of arsenate but declined at higher concentrations and longer duration of treatment.

CONCLUSIONS

The catalase activity was found to be most susceptible to arsenate stress as its activity started declining from very beginning of the experiment. P. cocoes also proved to be an excellent accumulator of arsenate whose concentration increased in the thallus corresponding to its increase in the treatment and duration. Thus, it can be utilized for active biomonitoring of arsenic pollution.

HBx protein of hepatitis B virus promotes reinitiation of DNA replication by regulating expression and intracellular stability of replication licensing factor CDC6

Prevention of re-replication via negative regulation of replication initiator proteins, such as CDC6, is key to maintenance of genomic integrity, whereas their up-regulation is generally associated with perturbation in cell cycle, genomic instability, and potentially, tumorigenesis. The HBx oncoprotein of hepatitis B virus is well known to deregulate cell cycle and has been intricately linked to development of hepatocellular carcinoma. Despite a clear understanding of the proliferative effects of HBx on cell cycle, a mechanistic link between HBx-mediated hepatocarcinogenesis and host cell DNA replication remains poorly perused. Here we show that HBx overexpression in both the cellular as well as the transgenic environment resulted in the accumulation of CDC6 through transcriptional and post-translational up-regulation. The HBx-mediated increase in CDK2 activity altered the E2F1-Rb (retinoblastoma) balance, which favored CDC6 gene expression by E2F1. Besides, HBx impaired the APC(Cdh1)-dependent protein degradation pathway and conferred intracellular stability to CDC6 protein. Increase in CDC6 levels correlated with increase in CDC6 occupancy on the β-globin origin of replication, suggesting increment in origin licensing and re-replication. In conclusion, our findings strongly suggest a novel role for CDC6 in abetting the oncogenic sabotage carried out by HBx and support the paradigm that pre-replicative complex proteins have a role in oncogenic transformation.