PS02.239: SPECIFIC INHIBITION OF BONE MORPHOGENIC PROTEIN (BMP4) AS A POTENTIAL THERAPEUTIC STRATEGY FOR ESOPHAGEAL ADENOCARCINOMA

2018 ◽  
Vol 31 (Supplement_1) ◽  
pp. 190-190
Author(s):  
Kausilia Krishnadath ◽  
Sanne Hoefnagel ◽  
Silvia Calpe ◽  
Matthew Read ◽  
Danielle Straub ◽  
...  
Keyword(s):  
Esophageal Adenocarcinoma ◽  
Conflicts Of Interest ◽  
Bmp Signaling ◽  
In Vivo Studies ◽  
Tumor Xenograft ◽  
In Vivo Models ◽  
Treatment Naïve ◽  
Bmp4 Expression

Abstract Background In Western countries, the highly malignant Esophageal adenocarcinoma (EAC) have the most dramatically rising incidence of all malignancies. BMP4 is a growth factor important for carcinogenesis. We found that BMP4 is aberrantly expressed in Barret's esophagus, the pecursor lesion of EAC, and that together with CDX2 drives the intestinalization of epithelial metaplasia. However, its role in esophageal adenocarcinoma (EAC) remains uncertain. Methods Method: To elucidate whether BMP4 is involved in malignancy in EAC we used an RNA sequencing database of 56 EAC treatment naive endoscopic biopsies to investigate if there is a subgroup of cancers with high BMP signaling. We validated results by qPCR and immunohistochemistry in matching tumor samples. Next we used our recently developed effective and highly specific anti-BMP4 antibodies(1,2) to study the effect of inhibition of BMP4 on both in vitro as well as in vivo models of EAC. Results Using a gene set that was recently published for BMP signaling, we were able to distinguish a subgroup of EAC patients with increased BMP signaling. By IHC we confirmed that 70% of EAC tumors express BMP4 at the protein level. We found that patients with high levels of BMP4 expression tend to have a poorer recurrence-free survival compared to patients with low BMP4 expression, which suggests a more aggressive tumor behavior in BMP4 expressing EAC tumors. Most importantly, inhibition of BMP4 function in EAC cells by our recently developed anti-BMP4 antibodies lead to an increase in chemo-sensitivity and a decreased in invasive and migratory capabilities in vitro. Preclinical in vivo studies with a patient-derived tumor xenograft mouse model of an EAC tumor confirmed that anti-BMP4 antibodies can effectively reduce tumor growth and synergistically act with chemotherapy agents. Conclusion We identified a subgroup of EAC with increased BMP signaling. Our studies support a role of BMP4 in chemo-resistance and invasiveness in EAC, and indicate that inhibition of BMP4 with highly our specific llama-derived antibodies is an attractive therapy for improving outcomes of EAC. Disclosure All authors have declared no conflicts of interest.

scholarly journals Design of PSMA ligands with modifications at the inhibitor part: an approach to reduce the salivary gland uptake of radiolabeled PSMA inhibitors?

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Veronika Barbara Felber ◽  
Manuel Amando Valentin ◽  
Hans-Jürgen Wester
Keyword(s):  
Salivary Gland ◽  
Solid Phase ◽  
Solid Phase Peptide Synthesis ◽  
In Vivo Studies ◽  
Tumor Xenograft ◽  
Tumor Uptake ◽  
Lncap Cells ◽  
High Affinity

Abstract Aim To investigate whether modifications of prostate-specific membrane antigen (PSMA)-targeted radiolabeled urea-based inhibitors could reduce salivary gland uptake and thus improve tumor-to-salivary gland ratios, several analogs of a high affinity PSMA ligand were synthesized and evaluated in in vitro and in vivo studies. Methods Binding motifs were synthesized ‘on-resin’ or, when not practicable, in solution. Peptide chain elongations were performed according to optimized standard protocols via solid-phase peptide synthesis. In vitro experiments were performed using PSMA+ LNCaP cells. In vivo studies as well as μSPECT/CT scans were conducted with male LNCaP tumor xenograft-bearing CB17-SCID mice. Results PSMA ligands with A) modifications within the central Zn2+-binding unit, B) proinhibitor motifs and C) substituents & bioisosteres of the P1′-γ-carboxylic acid were synthesized and evaluated. Modifications within the central Zn2+-binding unit of PSMA-10 (Glu-urea-Glu) provided three compounds. Thereof, only natLu-carbamate I (natLu-3) exhibited high affinity (IC50 = 7.1 ± 0.7 nM), but low tumor uptake (5.31 ± 0.94% ID/g, 1 h p.i. and 1.20 ± 0.55% ID/g, 24 h p.i.). All proinhibitor motif-based ligands (three in total) exhibited low binding affinities (> 1 μM), no notable internalization and very low tumor uptake (< 0.50% ID/g). In addition, four compounds with P1′-ɣ-carboxylate substituents were developed and evaluated. Thereof, only tetrazole derivative natLu-11 revealed high affinity (IC50 = 16.4 ± 3.8 nM), but also this inhibitor showed low tumor uptake (3.40 ± 0.63% ID/g, 1 h p.i. and 0.68 ± 0.16% ID/g, 24 h p.i.). Salivary gland uptake in mice remained at an equally low level for all compounds (between 0.02 ± 0.00% ID/g and 0.09 ± 0.03% ID/g), wherefore apparent tumor-to-submandibular gland and tumor-to-parotid gland ratios for the modified peptides were distinctly lower (factor 8–45) than for [177Lu]Lu-PSMA-10 at 24 h p.i. Conclusions The investigated compounds could not compete with the in vivo characteristics of the EuE-based PSMA inhibitor [177Lu]Lu-PSMA-10. Although two derivatives (3 and 11) were found to exhibit high affinities towards LNCaP cells, tumor uptake at 24 h p.i. was considerably low, while uptake in salivary glands remained unaffected. Optimization of the established animal model should be envisaged to enable a clear identification of PSMA-targeting radioligands with improved tumor-to-salivary gland ratios in future studies.

scholarly journals Anti-Inflammatory Potential of Daturaolone from Datura innoxia Mill.: In Silico, In Vitro and In Vivo Studies

2021 ◽  
Vol 14 (12) ◽  
pp. 1248
Author(s):  
Muhammad Waleed Baig ◽  
Humaira Fatima ◽  
Nosheen Akhtar ◽  
Hidayat Hussain ◽  
Mohammad K. Okla ◽  
...  
Keyword(s):  
In Silico ◽  
Therapeutic Potential ◽  
In Vivo Studies ◽  
Metabolic Reaction ◽  
Datura Innoxia ◽  
In Vivo Models ◽  
Immobility Time ◽  
Anti Inflammatory

Exploration of leads with therapeutic potential in inflammatory disorders is worth pursuing. In line with this, the isolated natural compound daturaolone from Datura innoxia Mill. was evaluated for its anti-inflammatory potential using in silico, in vitro and in vivo models. Daturaolone follows Lipinski’s drug-likeliness rule with a score of 0.33. Absorption, distribution, metabolism, excretion and toxicity prediction show strong plasma protein binding; gastrointestinal absorption (Caco-2 cells permeability = 34.6 nm/s); no blood–brain barrier penetration; CYP1A2, CYP2C19 and CYP3A4 metabolism; a major metabolic reaction, being aliphatic hydroxylation; no hERG inhibition; and non-carcinogenicity. Predicted molecular targets were mainly inflammatory mediators. Molecular docking depicted H-bonding interaction with nuclear factor kappa beta subunit (NF-κB), cyclooxygenase-2, 5-lipoxygenase, phospholipase A2, serotonin transporter, dopamine receptor D1 and 5-hydroxy tryptamine. Its cytotoxicity (IC50) value in normal lymphocytes was >20 µg/mL as compared to cancer cells (Huh7.5; 17.32 ± 1.43 µg/mL). Daturaolone significantly inhibited NF-κB and nitric oxide production with IC50 values of 1.2 ± 0.8 and 4.51 ± 0.92 µg/mL, respectively. It significantly reduced inflammatory paw edema (81.73 ± 3.16%), heat-induced pain (89.47 ± 9.01% antinociception) and stress-induced depression (68 ± 9.22 s immobility time in tail suspension test). This work suggests a possible anti-inflammatory role of daturaolone; however, detailed mechanistic studies are still necessary to corroborate and extrapolate the findings.

scholarly journals Effect of Resveratrol on In Vitro and In Vivo Models of Diabetic Retinophathy: A Systematic Review

2019 ◽  
Vol 20 (14) ◽  
pp. 3503 ◽  
Author(s):  
Mario D. Toro ◽  
Katarzyna Nowomiejska ◽  
Teresio Avitabile ◽  
Robert Rejdak ◽  
Sarah Tripodi ◽  
...  
Keyword(s):  
Diabetic Retinopathy ◽  
Risk Of Bias ◽  
In Vivo Studies ◽  
Exclusion Criteria ◽  
In Vivo Models ◽  
In Vivo Experiments ◽  
Retinal Pathology ◽  
Full Text Review

A large number of preclinical studies suggest the involvement of resveratrol in the prevention and treatment of eye diseases induced by oxidative stress and inflammation. We tested the hypothesis that resveratrol influences many pathways of in vitro and in vivo models of diabetic retinopathy through a systematic literature review of original articles. The review was conducted in accordance with the PRISMA guidelines. A literature search of all original articles published until April 2019 was performed. The terms “resveratrol” in combination with “retina”, “retinal pathology”, “diabetic retinopathy” and “eye” were searched. Possible biases were identified with the adopted SYRCLE’s tool. Eighteen articles met inclusion/exclusion criteria for full-text review. Eleven of them included in vitro experiments, 11 studies reported in vivo data and 3 studies described both in vitro and in vivo experiments. Most of the in vivo studies did not include data that would allow exclusion of bias risks, according to SYRCLE’s risk of bias tool. Both in vitro and in vivo data suggest anti-apoptotic, anti-inflammatory and anti-oxidative actions of resveratrol in models of diabetic retinopathy. However, results on its anti-angiogenic effects are contradictory and need more rigorous studies.

Somatic Mutational Landscape of AML with Inv(16) and t(8;21) Identifies Two Distinct Patterns in Relapse Tumors

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 2362-2362
Author(s):  
Raman B. Sood ◽  
Nancy F Hansen ◽  
Frank X Donovan ◽  
Blake Carrington ◽  
Baishali Maskeri ◽  
...  
Keyword(s):  
Conflicts Of Interest ◽  
Clonal Evolution ◽  
Treatment Strategies ◽  
Gene Mutations ◽  
Driver Gene ◽  
Intrinsic Resistance ◽  
Driver Genes ◽  
In Vivo Models

Abstract Acute myeloid leukemia (AML) is a heterogeneous disease with a wide prognostic spectrum ranging from poor to good depending upon the underlying mutations and/or cytogenetic abnormalities. Although AMLs with inv(16)/t(16:16) or t(8,21), collectively referred to as core binding factor leukemias (CBF-AMLs), are classified as prognostically favorable, such patients often succumb to their disease following relapse after an initial response to cytarabine/anthracyclin-based treatment regimens. Thus, to develop successful treatment strategies, it is critical to understand the mechanisms leading to disease relapse and target them with novel therapeutic approaches. To pursue this goal, we applied genomic approaches (whole exome sequencing and single nucleotide polymorphism arrays) on DNA from samples collected at sequential time points (i.e., diagnosis, complete remission and relapse) in seven patients with inv(16) and six patients with t(8;21). We identified mutations in several previously identified AML driver genes, such as KIT, FLT3, DNMT3A, EZH2, SMC1A, SMC3, WT1 and NRAS. Three relapse samples showed mosaicism for monosomy/disomy of the region of chromosome 3 containing GATA2. Overall, our data revealed two distinct profiles that support different mechanisms of relapse: 1) diagnosis and relapse blasts harbor the same driver gene mutations, indicating the intrinsic resistance of the major clones present at diagnosis to treatment regimen used; 2) diagnosis and relapse tumors have different driver gene mutations, indicating disease clonal evolution possibly through treatment selective pressure. Furthermore, our data has identified previously unreported putative driver genes for AML. Among these, we identified same somatic variant (R222G) in DHX15, an RNA helicase involved in splicing, in two patients at diagnosis. The variant was also detected at relapse in one of these patients. Functional validation of the mechanistic roles of wild type and mutated DHX15 in hematopoiesis and leukemogenesis, respectively, is ongoing in in vitro and in vivo models. Disclosures No relevant conflicts of interest to declare.

scholarly journals Assessment of biosafety and toxicity of hydrophilic gel for implantation in experimental in vitro and in vivo models 

2021 ◽  
Author(s):  
Natalia Bezdieniezhnykh ◽  
Alexandra Lykhova ◽  
Tamara Kozak ◽  
Taras Zadvornyi ◽  
Olena Voronina ◽  
...  
Keyword(s):  
Human Peripheral Blood ◽  
Clinical Manifestations ◽  
Peripheral Blood Lymphocytes ◽  
Model Systems ◽  
In Vivo Studies ◽  
In Vivo Models ◽  
Pharmacologically Active ◽  
Hydrophilic Gel

Abstract Background: The assessment of biosafety of pharmacologically active substances is crucial for determining the feasibility of their medical use. There are controversial issues regarding the use of substances of different origins as implants. Methods: We have conducted the comprehensive studies to determine the in vivo toxicity and in vitro genotoxicity of new generation of hydrophilic gel for implantation (production name of the substance "Activegel") to detail its characteristics and assess its biosafety. Results: In vivo studies have shown the absence of clinical manifestations of intoxication in animals and no abnormalities in their physiological condition, general and biochemical blood tests. Evaluation of the site of the gel application showed no inflammatory reaction and evidenced on normal state of tissues of animal skin. The results of the genotoxicity test indicated that the gel did not affect the parameters of DNA comets and, accordingly, had no genotoxic effect on human peripheral blood lymphocytes. When studying the effect of the gel on malignantly transformed cells in vitro, it was found that the gel for implantation did not change the proliferative activity and viability of human breast cancer cells. Conclusions: Comprehensive in vitro and in vivo study using various experimental model systems showed that the hydrophilic gel for implantation "Activegel" is non-toxic.

Cytotoxic Activity of Anti-CD20-hIFN-α on Rituximab-Resistant B-NHL Clones and Synergy with Chemotherapy,

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3499-3499 ◽  
Author(s):  
Gabriel G Vega ◽  
Mario I Vega ◽  
Sara Huerta-Yepez ◽  
Ali Jazirehi ◽  
Hector Mayani ◽  
...  
Keyword(s):  
Cell Lines ◽  
Conflicts Of Interest ◽  
Tumor Xenograft ◽  
Antibody Concentration ◽  
Wild Type ◽  
Anti Cd20 ◽  
Hodgkin's Lymphomas ◽  
Apoptotic Effects

Abstract Abstract 3499 Rituximab (chimeric anti-CD20 mAb) (Rtx) has been successfully used in the treatment of patients with B-cell non-Hodgkin's lymphomas (B-NHLs). The combination treatment with chemotherapy results in achieving high response rates and prolongation of survival. However, a subset of patients does not initially respond to treatment and many responding patients relapse and no longer respond to further treatments. Currently, there are no alternative therapies for resistant patients. The mechanism of resistance in vivo is not clear. However, we have explored a potential mechanism by developing in vitro several clones of Rtx-resistant (RR) variants for several B-NHL cell lines and characterized their properties. Briefly, unlike the parental wild-type, the RR clones express CD20 but no longer respond to treatment with Rtx or combination with cytotoxic drugs. Further, these clones overexpress the activity of several survival/anti-apoptotic pathways [1]. It is not known whether chemical modification of Rtx might be necessary to exert its activity and signaling on the RR clones. Hence, a recent report demonstrated that a fusion protein consisting of Rtx and human IFN-α (anti-CD20-hIFN-α) exhibited superior activity over Rtx, IFN-α, or combination of Rtx and IFN-α, and exhibited significant anti-proliferative and apoptotic effects in vitro with several B-NHL cell lines and in vivo an anti-tumor xenograft response [2]. These findings prompted us to investigate the effect of anti-CD20-hIFN-α on the RR clones. We hypothesized that anti-CD20-hIFN-α may exert an anti-proliferative and apoptotic effects on the RR clones and may also synergize when used in combination with chemotherapy. In this study, we used the B-NHL line Ramos (Burkitt) and 2F7 (AIDS-related) and their respective Ramos RR1 and 2F7 RR1 clones as models. We examined the effects of anti-CD20-hIFN-α and Rtx on the wild-type and RR clones following treatment with IgG isotype control, Rtx, anti-CD20-hIFN-α, CDDP (10 mg/ml) and Treanda® (Bendamustine) (5 mg/ml), as well as combinations. Treatment of 2F7 with single agents alone had no cytotoxic effect; however, treatment with the combination of Rtx and CDDP or Treanda® or anti-CD20-hIFN-α plus CDDP or Treanda® resulted in significant cytotoxicity. Treatment of Ramos resulted in similar findings observed with 2F7, however, the anti-CD20-hIFN-α alone was significantly cytotoxic to Ramos cells. Importantly, whereas treatment of 2F7 RR1 or Ramos RR1 with Rtx or Rtx plus CDDP or Treanda® had no cytotoxic effects (as expected), the treatment with the anti-CD20-hIFN-α alone had significant cytotoxicity and synergy was observed when used in combination with CDDP or Treanda®. In all of the above experiments, the level of cytotoxicity was a function of the antibody concentration used (range 10–30 μg/ml). The mechanism by which anti-CD20-hIFN-α signals the RR clones for cytotoxicity and sensitization was examined. Preliminary findings show that treatment of the RR clones with anti-CD20-hIFN-α inhibits the activity of p38MAPK survival pathway and also inhibits the anti-apoptotic gene products, Bcl-2/BclXL and upregulates the pro-apoptotic expression of Bax. These findings established, for the first time, that modification of Rtx by fusion with IFN-α was cytotoxic on the RR clones and synergized with chemotherapy. The findings also show, unlike Rtx that, anti-CD20-hIFN-α signals the RR cells and inhibits survival/antiapoptotic pathways leading to direct cytotoxicity and chemo-sensitization. The molecular signaling mediated by anti-CD20-hIFN-α on the cell membrane of RR cells leading to inhibition of survival pathways will be presented. Disclosures: No relevant conflicts of interest to declare.

Assessing CD97 and CD99 As Markers of Leukaemia Initiating Cells in Paediatric ALL

Blood ◽  
2012 ◽  
Vol 120 (21) ◽  
pp. 1882-1882 ◽  
Author(s):  
Charlotte Victoria Cox ◽  
Paraskevi Diamanti ◽  
Allison Blair
Keyword(s):  
Functional Capacity ◽  
Conflicts Of Interest ◽  
Residual Disease ◽  
Survival Rates ◽  
In Vivo Studies ◽  
Nsg Mice ◽  
Early Treatment Response ◽  
Current Therapies

Abstract Abstract 1882 Overall survival rates in paediatric acute lymphoblastic leukaemia (ALL) have dramatically improved but around 20% do not respond to current therapies and subsequently relapse. Leukaemia initiating cells (LIC) are the topic of much investigation, as these cells can self-renew and may have the potential to cause relapse. It has been shown that multiple subpopulations of ALL cells have the ability to initiate the disease in immune deficient mouse models. Therefore, treatment should be targeted at all cells with this capacity, if the disease is to be eradicated. Minimal residual disease (MRD) detection is an invaluable tracking tool to assess early treatment response and recent studies have highlighted potential markers that may improve the sensitivity of MRD detection by flow cytometry. CD97 and CD99 are two markers which were over expressed in paediatric ALL. Incorporating these markers into investigations of LIC may allow discrimination of leukaemia cells from normal haemopoietic stem cells (HSC). In this study we evaluated the expression of CD34 in combination with CD97 in B cell precursor (BCP) ALL cases and CD99 in T-ALL cases and subsequently assessed the functional capacity of the sorted subpopulations in vitro and in vivo. Ten ALL samples (6 B-ALL & 4 T-ALL) with a median age 7 years (range 2–15 years) were studied. One B-ALL case and 3 T-ALL cases were considered high risk by molecular assessment of MRD at day 28 of treatment. Flow cytometric analyses of the ALL samples and 8 normal haemopoietic cell samples demonstrated that both CD97 and CD99 were over expressed in ALL patients (78.9±14.8% & 76.4±32.8%, respectively) when compared to normal haemopoietic cells (14.1±25.4%; p=0.001, 47.1±10%; p=0.03, respectively). Cells were sorted for expression/lack of expression of these markers and proliferation of the sorted cells was assessed in suspension culture over a 6 week period. In the B-ALL patients the CD34+/CD97+ subpopulation represented the bulk of leukaemia cells (65.2±32.1%), the CD34−/CD97+ the smallest fraction (3.3±2.4%) with the CD34+/CD97− and CD34−/CD97− subpopulations representing 21.1±31.5% and 10.5±5.8% of cells, respectively. When the functional capacity of these subpopulations was assessed in vitro greatest expansion was observed in cells derived from CD34+/CD97− subpopulation (2–173 fold) from 9.4×103 at initiation up to 1.5×106 cells at week 6. Expansion was also observed, to a lesser extent in the CD34−/CD97− subpopulation (3.4–28 fold) from 8×103 up to 1.4×106 cells. No expansion was observed in cultures of CD34+/CD97+ and CD34−/CD97− subpopulations but cells were maintained throughout the culture period. These sorted subpopulations were also inoculated into NOD/LtSz-SCID IL-2Rγc null (NSG) mice to evaluate repopulating capacity. To date, engraftment has been achieved with 3 subpopulations; CD34+/CD97+ (3–28.8% CD45+), CD34+/CD97− (0.5–25.5% CD45+) and CD34−/CD97+ (23.8% CD45+) cells. When the functional capacity of T-ALL cases was assessed the CD34+/CD99+ subpopulation represented the bulk of cells at sorting (51.87±47.2%), the CD34+/CD99- subpopulation was the smallest (0.9±0.8%) and the CD34−/CD99+ and CD34−/CD99− subpopulations represented 32.1±38.9% and 27.2±33.4% of cells, respectively. Greatest expansion was observed in cultures of CD34+/CD99- cells (4.6–1798 fold) from 7.5×103 up to 2.6×106 cells at week 6. The other 3 subpopulations expanded to a lesser extent (1.3–216 fold) from 5×103 up to 1.8×106 cells. When the functional capacity of these cells was assessed in NSG mice, engraftment was achieved in all subpopulations; CD34+/CD99+ (87–90.5% CD45+), CD34+/CD99− (1.5–84.9% CD45+), CD34−/CD99+ (31.3–98.6% CD45+) and CD34−/CD99− (3–92.9% CD45+). In some cases, cells recovered from BM of NSG inoculated with CD99− cells had high expression of CD99, typical of the patient samples at diagnosis, indicating that the inoculated CD99− cells had differentiated in vivo. Studies are ongoing to assess the self-renewal capacity of these subpopulations by serial transplantation. The findings to date indicate that targeting CD97 and CD99, either alone or in combination with CD34 would not eliminate all cells with the capacity to initiate and maintain B-ALL and T-ALL, respectively. Further developments in therapy may require targeting leukaemogenic pathways, rather than only cell surface markers to improve survival outcome in paediatric ALL. Disclosures: No relevant conflicts of interest to declare.

BMP activity controlled by BMPER regulates the proinflammatory phenotype of endothelium

Blood ◽  
2011 ◽  
Vol 118 (18) ◽  
pp. 5040-5049 ◽  
Author(s):  
Thomas Helbing ◽  
René Rothweiler ◽  
Elena Ketterer ◽  
Lena Goetz ◽  
Jennifer Heinke ◽  
...  
Keyword(s):  
Vascular Endothelial Cells ◽  
Ex Vivo ◽  
Leukocyte Adhesion ◽  
Vascular Inflammation ◽  
Bmp Signaling ◽  
In Vivo Models ◽  
In Vivo Experiments ◽  
And Migration

Abstract The endothelium plays a pivotal role in vascular inflammation. Here we study bone morphogenetic protein (BMP) signaling in endothelial inflammation and in particular the role of BMPER, an extracellular BMP modulator that is important in vascular development and angiogenesis. Using the BMP antagonist dorsomorphin or BMP2 as an agonist we show that BMP signaling is essential for the inflammatory response of vascular endothelial cells as demonstrated by intravital microscopy. We found that BMPER is decreased in inflammation similar to vascular protective genes like KLF2 and eNOS. Using in vitro and in vivo models we show that BMPER is down-regulated through the TNFα-NFκB-KLF2 signaling pathway. Functionally, lack of BMPER induced by siRNA or in BMPER+/− mice confers a proinflammatory endothelial phenotype with reduced eNOS levels and enhanced expression of adhesion molecules leading to increased leukocyte adhesion and extravasation in ex vivo and in vivo experiments. Vice versa, addition of BMPER exerts endothelium protective functions and antagonizes TNFα induced inflammation. Mechanistically, we demonstrate that these effects of BMPER are dependent on BMP signaling because of enhanced NFκB activity. In conclusion, the BMP modulator BMPER is a new protective regulator of vascular inflammation that modulates leukocyte adhesion and migration in vitro and in vivo.

scholarly journals Assessment of In Vitro Bioaccessibility and In Vivo Oral Bioavailability as Complementary Tools to Better Understand the Effect of Cooking on Methylmercury, Arsenic, and Selenium in Tuna

Toxics ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 27
Author(s):  
Tania Charette ◽  
Danyel Bueno Dalto ◽  
Maikel Rosabal ◽  
J. Jacques Matte ◽  
Marc Amyot
Keyword(s):  
Oral Bioavailability ◽  
Fish Muscle ◽  
In Vitro Models ◽  
In Vivo Studies ◽  
In Vivo Models ◽  
Exposure Pathway ◽  
In Vitro Bioaccessibility ◽  
Kinetics Of

Fish consumption is the main exposure pathway of the neurotoxicant methylmercury (MeHg) in humans. The risk associated with exposure to MeHg may be modified by its interactions with selenium (Se) and arsenic (As). In vitro bioaccessibility studies have demonstrated that cooking the fish muscle decreases MeHg solubility markedly and, as a consequence, its potential absorption by the consumer. However, this phenomenon has yet to be validated by in vivo models. Our study aimed to test whether MeHg bioaccessibility can be used as a surrogate to assess the effect of cooking on MeHg in vivo availability. We fed pigs raw and cooked tuna meals and collected blood samples from catheters in the portal vein and carotid artery at: 0, 30, 60, 90, 120, 180, 240, 300, 360, 420, 480 and 540 min post-meal. In contrast to in vitro models, pig oral bioavailability of MeHg was not affected by cooking, although the MeHg kinetics of absorption was faster for the cooked meal than for the raw meal. We conclude that bioaccessibility should not be readily used as a direct surrogate for in vivo studies and that, in contrast with the in vitro results, the cooking of fish muscle did not decrease the exposure of the consumer to MeHg.

scholarly journals Different Classes of ABL1 Fusions Activate Different Downstream Signalling Nodes

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 2628-2628
Author(s):  
Lauren M Brown ◽  
Hannah Huckstep ◽  
Jarrod Sandow ◽  
Ray C Bartolo ◽  
Nadia Davidson ◽  
...  
Keyword(s):  
Tyrosine Kinase ◽  
Kinase Inhibitors ◽  
Conflicts Of Interest ◽  
Sh2 Domain ◽  
Signalling Pathways ◽  
Stable Isotope Labelling ◽  
In Vivo Models ◽  
Sh3 Domains

Abstract Background: Philadelphia-like acute lymphoblastic leukaemia (Ph-like ALL) is a high-risk subtype of ALL driven by a range of tyrosine kinase and cytokine receptor rearrangements. ABL1-class rearrangements (ABL1, ABL2, CSF1R and PDGFRB) account for 17% of Ph-like ALL cases in children, and are clinically important to identify as they can be therapeutically targeted with tyrosine kinase inhibitors (TKIs). While the p190 BCR-ABL1 fusion is well described, less is known about the function and downstream signalling by rare ABL1 fusions. We identified a rare ABL1 fusion, SFPQ-ABL1, in a paediatric B-ALL patient using RNA-sequencing. This fusion lacks the ABL1 Src-homology-3 (SH3) and part of the SH2 domain, which are retained in BCR-ABL1. Other ABL1 fusions, RCSD1-ABL1 and SNX2-ABL1, have a similar structure. In this work we have utilised phosphoproteomics and Stable Isotope Labelling by Amino Acids in Cell Culture (SILAC), as well as in vitro and in vivo models, to determine differential signalling pathways between SFPQ-ABL1 and BCR-ABL1. Methods: We cloned SFPQ-ABL1 from patient cDNA, and engineered SFPQ-ABL1 and BCR-ABL1 fusions to include or delete the SH2 and SH3 domains. We performed proliferation and viability assays to assess the ability of these fusions to transform Ba/F3 cells and test sensitivity to TKIs. We performed total phosphopeptide and phosphotyrosine enrichments and utilised mass spectrometry to identify the phosphoproteome activated by canonical SFPQ-ABL1 and BCR-ABL1. Over representation analysis was performed on phosphopeptides significantly differing between BCR-ABL and SFPQ-ABL (Log fold change cut-off > 2.5) using the Gene Ontology (GO) knowledge base under the biological process category. Furthermore, we compared the phosphoproteome of canonical SFPQ-ABL1 to SFPQ-ABL1 with the SH2 and SH3 domains reintroduced (SFPQ-ABL1+SH). We have also developed novel mouse models, using syngeneic transplantation, of SFPQ-ABL1 and SNX2-ABL1 driven leukaemia. Results: SFPQ-ABL1 expressing Ba/F3 cells are sensitive to cell death induced by TKIs that block ABL1. Interestingly, while SFPQ-ABL1 and BCR-ABL1 both effectively blocked apoptosis, SFPQ-ABL1 was less able to drive cytokine-independent proliferation. Phosphoproteomic analysis showed that BCR-ABL1 and SFPQ-ABL1 differentially activate downstream signalling pathways, including SH-binding proteins. Hierarchical clustering of phosphopeptides quantified from cells expressing canonical BCR-ABL1, SFPQ-ABL1, and SFPQ-ABL1+SH, demonstrated that BCR-ABL1 and SFPQ-ABL1+SH were more similar to each other than to SFPQ-ABL1. SFPQ-ABL1 expression resulted in phosphorylation of proteins involved in RNA processing, metabolism and splicing, suggesting that SFPQ region of SFPQ-ABL1 also contributes to signalling. Conclusions: In this study, we have utilised phosphoproteomics for the unbiased identification of signalling nodes that are required for the function of different classes of ABL fusions. We have developed novel in vitro and in vivo models to further understand how these fusions function to drive leukaemia. Our data also suggests that ABL1 fusion partners play a role beyond dimerization and transphosphorylation of the kinase domains in oncogenic signalling, but further study is needed to establish the contribution to leukaemogenesis. Establishing signalling pathways that are critical to the function of rare ABL1 fusions may inform clinical approaches to treating this disease. Disclosures No relevant conflicts of interest to declare.

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