Caged noble metals: Encapsulation of a cytotoxic platinum(II)-gold(I) compound within the ferritin nanocage

The encapsulation of Pt and Au-based anticancer agents within a protein cage is a promising way to enhance the selectivity of these potential drugs. Here a cytotoxic organometallic compound containing platinum(II) and gold(I) has been encapsulated within a ferritin nanocage (AFt). Inductively plasma coupled mass spectrometry data, collected to evaluate the amount of Pt and Au within the cage, indicate disruption of the starting heterobimetallic complex upon encapsulation within the nanocage. The drug-loaded protein (Pt(II)/Au(I)-AFt) has been characterized by UV-Vis spectroscopy, circular dichroism and X-ray diffraction analysis. Data indicate that the protein maintains its fold upon encapsulation of the metallodrug and that Au(I) and Pt(II)-containing fragments are encapsulated within the AFt cage, with Au(I) ion that binds the side chain of Cys126 and Pt(II) in the bulk, respectively. The in vitro cytotoxicity of Pt(II)Au(I)-AFt, as well as that of the free heterobimetallic complex, has been comparatively evaluated on human cervix and breast cancer cells and against cardiomyoblasts and keratinocytes non-tumorigenic cells. Our data demonstrate that it is possible to obtain a protein nanocarrier containing both Pt and Au atoms starting from a bimetallic compound, opening the way for the design and development of new potential drugs based on protein nanocarriers.

Correction: Selenium effects on the metabolism of a Se-metabolizing Lactobacillus reuteri: analysis of envelope-enriched and extracellular proteomes

Correction for 'Selenium effects on the metabolism of a Se-metabolizing Lactobacillus reuteri: analysis of envelope-enriched and extracellular proteomes' by E. Mangiapane et al., Mol. BioSyst., 2014, 10, 1272-1280.

Multiple Reaction Monitoring Tandem Mass Spectrometry Approach for the Identification of Biological Fluids at Crime Scene Investigations

Knowledge of the nature of biofluids at a crime scene is just as important as DNA test to link the nature of the biofluid, the criminal act, and the dynamics of the crime. Identification of methods currently used for each biological fluid (blood, semen, saliva, urine) suffer from several limitations including instability of assayed biomolecules, and low selectivity and specificity; as an example of the latter issue, it is not possible to discriminate between alpha-amylase 1 (present in saliva) and alpha-amylase 2 (present in semen and vaginal secretion. In this context, the aim of the work has been to provide a predictive protein signature characteristic of each biofluid by the recognition of specific peptides unique for each protein in a single analysis. A panel of four protein biomarkers for blood, four for saliva, five for semen, and two for urine has been monitored has been monitored by using a single multiple reaction monitoring (MRM)-based method targeting concomitantly 46 different peptides. Then, The optimized method allows four biological matrices to be identified when present on their own or in 50:50 mixture with another biofluid. Finally, a valid strategy combining both DNA analysis and liquid chromatographic-tandem mass spectrometric multiple reaction monitoring (LC-MS-MRM) identification of biofluids on the same sample has been demonstrated to be particularly effective in forensic investigation of real trace evidence collected at a crime scene.

Gold-based drug encapsulation within a ferritin nanocage: X-ray structure and biological evaluation as a potential anticancer agent of the Auoxo3-loaded protein

Auoxo3, a cytotoxic gold(iii) compound, was encapsulated within a ferritin nanocage. Inductively coupled plasma mass spectrometry, circular dichroism, UV-Vis absorption spectroscopy and X-ray crystallography confirm the potential-drug encapsulation. The structure shows that naked Au(i) ions bind to the side chains of Cys48, His49, His114, His114 and Cys126, Cys126, His132, His147. The gold-encapsulated nanocarrier has a cytotoxic effect on different aggressive human cancer cells, whereas it is significantly less cytotoxic for non-tumorigenic cells.

Photodegradation and ecotoxicology of acyclovir in water under UV254 and UV254/H2O2 processes

The photochemical and ecotoxicological fate of acyclovir (ACY) through UV₂₅₄ direct photolysis and in the presence of hydroxyl radicals (UV₂₅₄/H₂O₂ process) were investigated in a microcapillary film (MCF) array photoreactor, which provided ultrarapid and accurate photochemical reaction kinetics. The UVC phototransformation of ACY was found to be unaffected by pH in the range from 4.5 to 8.0 and resembled an apparent autocatalytic reaction. The proposed mechanism included the formation of a photochemical intermediate (ϕ_ACY = (1.62 ± 0.07)·10^-3 mol ein^-1) that further reacted with ACY to form by-products (k' = (5.64 ± 0.03)·10^-3 M^-1 s^-1). The photolysis of ACY in the presence of hydrogen peroxide accelerated the removal of ACY as a result of formation of hydroxyl radicals. The kinetic constant for the reaction of OH radicals with ACY (k_OH/ACY) determined with the kinetic modeling method was (1.23 ± 0.07)·10⁹ M^-1 s^-1 and with the competition kinetics method was (2.30 ± 0.11)·10⁹ M^-1 s^-1 with competition kinetics. The acute and chronic effects of the treated aqueous mixtures on different living organisms (Vibrio fischeri, Raphidocelis subcapitata, D. magna) revealed significantly lower toxicity for the samples treated with UV₂₅₄/H₂O₂ in comparison to those collected during UV₂₅₄ treatment. This result suggests that the addition of moderate quantity of hydrogen peroxide (30-150 mg L^-1) might be a useful strategy to reduce the ecotoxicity of UV₂₅₄ based sanitary engineered systems for water reclamation.

Modified denatured lysozyme effectively solubilizes fullerene c60 nanoparticles in water

Fullerenes, allotropic forms of carbon, have very interesting pharmacological effects and engineering applications. However, a very low solubility both in organic solvents and water hinders their use. Fullerene C60, the most studied among fullerenes, can be dissolved in water only in the form of nanoparticles of variable dimensions and limited stability. Here the effect on the production of C60 nanoparticles by a native and denatured hen egg white lysozyme, a highly basic protein, has been systematically studied. In order to obtain a denatured, yet soluble, lysozyme derivative, the four disulfides of the native protein were reduced and exposed cysteines were alkylated by 3-bromopropylamine, thus introducing eight additional positive charges. The C60 solubilizing properties of the modified denatured lysozyme proved to be superior to those of the native protein, allowing the preparation of biocompatible highly homogeneous and stable C60 nanoparticles using lower amounts of protein, as demonstrated by dynamic light scattering, transmission electron microscopy and atomic force microscopy studies. This lysozyme derivative could represent an effective tool for the solubilization of other carbon allotropes.

Quantitative determination of free D-Asp, L-Asp and N-methyl-D-aspartate in mouse brain tissues by chiral separation and Multiple Reaction Monitoring tandem mass spectrometry

Several studies have suggested that free d-Asp has a crucial role in N-methyl d-Asp receptor-mediated neurotransmission playing very important functions in physiological and pathological processes. This paper describes the development of an analytical procedure for the direct and simultaneous determination of free d-Asp, l-Asp and N-methyl d-Asp in specimens of different mouse brain tissues using chiral LC-MS/MS in Multiple Reaction Monitoring scan mode. After comparing three procedures and different buffers and extraction solvents, a simple preparation procedure was selected the analytes of extraction. The method was validated by analyzing l-Asp, d-Asp and N-methyl d-Asp recovery at different spiked concentrations (50, 100 and 200 pg/μl) yielding satisfactory recoveries (75–110%), and good repeatability. Limits of detection (LOD) resulted to be 0.52 pg/μl for d-Asp, 0.46 pg/μl for l-Asp and 0.54 pg/μl for NMDA, respectively. Limits of quantification (LOQ) were 1.57 pg/μl for d-Asp, 1.41 pg/μl for l-Asp and 1.64 pg/μl for NMDA, respectively. Different concentration levels were used for constructing the calibration curves which showed good linearity. The validated method was then successfully applied to the simultaneous detection of d-Asp, l-Asp and NMDA in mouse brain tissues. The concurrent, sensitive, fast, and reproducible measurement of these metabolites in brain tissues will be useful to correlate the amount of free d-Asp with relevant neurological processes, making the LC-MS/MS MRM method well suited, not only for research work but also for clinical analyses.

X-ray Structure of the Carboplatin-Loaded Apo-Ferritin Nanocage

The second-generation Pt anticancer agent carboplatin (CBDCA) was encapsulated within the apo horse spleen ferritin (AFt) nanocage, and the X-ray structure of the drug-loaded protein was refined at 1.49 Å resolution. Two Pt binding sites, different from the one observed in the cisplatin-encapsulated AFt, were identified in Ft subunits by inspection of anomalous electron density maps at two wavelengths and difference Fourier electron density maps, which provide the necessary sensitivity to discriminate between Pt from CBDCA and Cd ions that are present in the crystallization conditions. Pt centers coordinate to the NE2 atom of His49 and to the NE2 atom of His132, both on the inner surface of the Ft nanocage.

Formyl peptide receptor 1 suppresses gastric cancer angiogenesis and growth by exploiting inflammation resolution pathways

Chronic inflammation can result from inadequate engagement of resolution mechanisms, mainly accomplished by specialized pro-resolving mediators (SPMs) arising from the metabolic activity of lipoxygenases (ALOX5/15) on ω-6 or ω-3 essential polyunsaturated fatty acids (PUFA). We previously demonstrated that formyl peptide receptor 1 (FPR1) suppresses gastric cancer (GC) by inhibiting its inflammatory/angiogenic potential. In this study, we asked whether FPR1 exploits inflammation resolution pathways to suppress GC angiogenesis and growth. Here, we demonstrate that genetic or pharmacologic modulation of FPR1 in GC cells regulated ALOX5/15 expression and production of the SPMs Resolvin D1 (RvD1) and Lipoxin B4 (LXB4). SPM treatment of GC cells abated their angiogenic potential. Genetic deletion of ALOX15 or of the RvD1 receptor GPR32 increased the angiogenic and tumorigenic activity of GC cells thereby mimicking FPR1 loss. Deletion/inhibition of ALOX5/15 or GPR32 blocked FPR1-mediated anti-angiogenic activities, indicating that ALOX5/15 and GPR32 are required for FPR1's pro-resolving action. An ω-3- or ω-6-enriched diet enforced SPM endogenous production in mice and inhibited growth of shFPR1 GC xenografts by suppressing their angiogenic activity. These data implicate that FPR1 and/or pro-resolving pathway components might be used as risk/prognostic markers for GC; ω-6/3-enriched diets, and targeting FPR1 or SPM machinery may be exploited for GC management.

Novel human bioactive peptides identified in Apolipoprotein B: Evaluation of their therapeutic potential

Host defence peptides (HDPs) are short, cationic amphipathic peptides that play a key role in the response to infection and inflammation in all complex life forms. It is increasingly emerging that HDPs generally have a modest direct activity against a broad range of microorganisms, and that their anti-infective properties are mainly due to their ability to modulate the immune response. Here, we report the recombinant production and characterization of two novel HDPs identified in human Apolipoprotein B (residues 887-922) by using a bioinformatics method recently developed by our group. We focused our attention on two variants of the identified HDP, here named r(P)ApoB_L and r(P)ApoB_S, 38- and 26-residue long, respectively. Both HDPs were found to be endowed with a broad-spectrum antimicrobial activity while they show neither toxic nor haemolytic effects towards eukaryotic cells. Interestingly, both HDPs were found to display a significant anti-biofilm activity, and to act in synergy with either commonly used antibiotics or EDTA. The latter was selected for its ability to affect bacterial outer membrane permeability, and to sensitize bacteria to several antibiotics. Circular dichroism analyses showed that SDS, TFE, and LPS significantly alter r(P)ApoB_L conformation, whereas slighter or no significant effects were detected in the case of r(P)ApoB_S peptide. Interestingly, both ApoB derived peptides were found to elicit anti-inflammatory effects, being able to mitigate the production of pro-inflammatory interleukin-6 and nitric oxide in LPS induced murine macrophages. It should also be emphasized that r(P)ApoB_L peptide was found to play a role in human keratinocytes wound closure in vitro. Altogether, these findings open interesting perspectives on the therapeutic use of the herein identified HDPs.

Cisplatin encapsulation within a ferritin nanocage: a high-resolution crystallographic study

Cisplatin (CDDP) can be encapsulated within the central cavity of reconstituted (apo)ferritin, (A)Ft, to form a drug-loaded protein of potential great interest for targeted cancer treatments. In this study, the interactions occurring between cisplatin and native horse spleen Ft in CDDP-encapsulated AFt are investigated by high-resolution X-ray crystallography. A protein bound Pt center is unambiguously identified in AFt subunits by comparative analysis of difference Fourier electron density maps and of anomalous dispersion data. Indeed, a [Pt(NH3)2H2O](2+) fragment is found coordinated to the His132 residue located on the inner surface of the large AFt spherical cage. Remarkably, Pt binding does not alter the overall physicochemical features (shape, volume, polarity/hydrophobicity and electrostatic potential) of the outer surface of the AFt nanocage. CDDP-encapsulated AFt appears to be an ideal nanocarrier for CDDP delivery to target sites, as it possesses high biocompatibility and can be internalized by receptor mediated endocytosis, thus carrying the drug to tumor tissue with higher selectivity than free CDDP.

Profiling Carbonylated Proteins in Heart and Skeletal Muscle Mitochondria from Trained and Untrained Mice

Understanding the relationship between physical exercise, reactive oxygen species, and skeletal muscle modification is important in order to better identify the benefits or the damages that appropriate or inappropriate exercise can induce. Heart and skeletal muscles have a high density of mitochondria with robust energetic demands, and mitochondria plasticity has an important role in both the cardiovascular system and skeletal muscle responses. The aim of this study was to investigate the influence of regular physical activity on the oxidation profiles of mitochondrial proteins from heart and tibialis anterior muscles. To this end, we used the mouse as animal model. Mice were divided into two groups: untrained and regularly trained. The carbonylated protein pattern was studied by two-dimensional gel electrophoresis followed by Western blot with anti-dinitrophenyl hydrazone antibodies. Mass spectrometry analysis allowed the identification of several different protein oxidation sites, including methionine, cysteine, proline, and leucine residues. A large number of oxidized proteins were found in both untrained and trained animals. Moreover, mitochondria from skeletal muscles and heart showed almost the same carbonylation pattern. Interestingly, exercise training seems to increase the carbonylation level mainly of mitochondrial proteins from skeletal muscle.

An interdomain network: the endobacterium of a mycorrhizal fungus promotes antioxidative responses in both fungal and plant hosts

Arbuscular mycorrhizal fungi (AMF) are obligate plant biotrophs that may contain endobacteria in their cytoplasm. Genome sequencing of Candidatus Glomeribacter gigasporarum revealed a reduced genome and dependence on the fungal host. RNA-seq analysis of the AMF Gigaspora margarita in the presence and absence of the endobacterium indicated that endobacteria have an important role in the fungal pre-symbiotic phase by enhancing fungal bioenergetic capacity. To improve the understanding of fungal-endobacterial interactions, iTRAQ (isobaric tags for relative and absolute quantification) quantitative proteomics was used to identify differentially expressed proteins in G. margarita germinating spores with endobacteria (B+), without endobacteria in the cured line (B-) and after application of the synthetic strigolactone GR24. Proteomic, transcriptomic and biochemical data identified several fungal and bacterial proteins involved in interspecies interactions. Endobacteria influenced fungal growth, calcium signalling and metabolism. The greatest effects were on fungal primary metabolism and respiration, which was 50% higher in B+ than in B-. A shift towards pentose phosphate metabolism was detected in B-. Quantification of carbonylated proteins indicated that the B- line had higher oxidative stress levels, which were also observed in two host plants. This study shows that endobacteria generate a complex interdomain network that affects AMF and fungal-plant interactions.

Identification of p38 MAPK and JNK as new targets for correction of Wilson disease-causing ATP7B mutants

Wilson disease (WD) is an autosomal recessive disorder that is caused by the toxic accumulation of copper (Cu) in the liver. The ATP7B gene, which is mutated in WD, encodes a multitransmembrane domain adenosine triphosphatase that traffics from the trans-Golgi network to the canalicular area of hepatocytes, where it facilitates excretion of excess Cu into the bile. Several ATP7B mutations, including H1069Q and R778L that are two of the most frequent variants, result in protein products, which, although still functional, remain in the endoplasmic reticulum. Thus, they fail to reach Cu excretion sites, resulting in the toxic buildup of Cu in the liver of WD patients. Therefore, correcting the location of these mutants by leading them to the appropriate functional sites in the cell should restore Cu excretion and would be beneficial to help large cohorts of WD patients. However, molecular targets for correction of endoplasmic reticulum-retained ATP7B mutants remain elusive. Here, we show that expression of the most frequent ATP7B mutant, H1069Q, activates p38 and c-Jun N-terminal kinase signaling pathways, which favor the rapid degradation of the mutant. Suppression of these pathways with RNA interference or specific chemical inhibitors results in the substantial rescue of ATP7B(H1069Q) (as well as that of several other WD-causing mutants) from the endoplasmic reticulum to the trans-Golgi network compartment, in recovery of its Cu-dependent trafficking, and in reduction of intracellular Cu levels.

CONCLUSION

Our findings indicate p38 and c-Jun N-terminal kinase as intriguing targets for correction of WD-causing mutants and, hence, as potential candidates, which could be evaluated for the development of novel therapeutic strategies to combat WD. (Hepatology 2016;63:1842-1859).

New oxylipins produced at the end of a diatom bloom and their effects on copepod reproductive success and gene expression levels

Diatoms are dominant photosynthetic organisms in the world's oceans and are considered essential in the transfer of energy to higher trophic levels. However, these unicellular organisms produce secondary metabolites deriving from the oxidation of fatty acids, collectively termed oxylipins, with negative effects on predators, such as copepods, that feed on them (e.g. reduction in survival, egg production and hatching success) and, indirectly, on higher trophic levels. Here, a multidisciplinary study (oxylipin measurements, copepod fitness, gene expression analyses, chlorophyll distribution, phytoplankton composition, physico-chemical characteristics) was carried out at the end of the spring diatom bloom in April 2011 in the Northern Adriatic Sea (Mediterranean Sea) in order to deeply investigate copepod-diatom interactions, chemical communication and response pathways. The results show that the transect with the lowest phytoplankton abundance had the lowest copepod egg production and hatching success, but the highest oxylipin concentrations. In addition, copepods in both the analyzed transects showed increased expression levels of key stress-related genes (e.g. heat-shock proteins, catalase, glutathione S-transferase, aldehyde dehydrogenase) compared to control laboratory conditions where copepods were fed with the dinoflagellate Prorocentrum minimum which does not produce any oxylipins. New oxylipins that have never been reported before for microalgae are described for the first time, giving new insights into the complex nature of plant-animal signaling and communication pathways at sea. This is also the first study providing insights on the copepod response during a diatom bloom at the molecular level.

Divergent behavior of hydrogen sulfide pools and of the sulfur metabolite lanthionine, a novel uremic toxin, in dialysis patients

Dialysis patients display a high cardiovascular mortality, the causes of which are still not completely explained, but are related to uremic toxicity. Among uremic toxins, homocysteine and cysteine are both substrates of cystathionine β-synthase and cystathionine γ-lyase in hydrogen sulfide biosynthesis, leading to the formation of two sulfur metabolites, lanthionine and homolanthionine, considered stable indirect biomarkers of its production. Hydrogen sulfide is involved in the modulation of multiple pathophysiological responses. In uremia, we have demonstrated low plasma total hydrogen sulfide levels, due to reduced cystathionine γ-lyase expression. Plasma hydrogen sulfide levels were measured in hemodialysis patients and healthy controls with three different techniques in comparison, allowing to discern the different pools of this gas. The protein-bound (the one thought to be the most active) and acid-labile forms are significantly decreased, while homolanthionine, but especially lanthionine, accumulate in the blood of uremic patients. The hemodialysis regimen plays a role in determining sulfur compounds levels, and lanthionine is partially removed by a single dialysis session. Lanthionine inhibits hydrogen sulfide production in cell cultures under conditions comparable to in vivo ones. We therefore propose that lanthionine is a novel uremic toxin. The possible role of high lanthionine as a contributor to the genesis of hyperhomocysteinemia in uremia is discussed.

Effect of temperature on the interaction of cisplatin with the model protein hen egg white lysozyme

The products of the reaction between cisplatin (CDDP) and the model protein hen egg white lysozyme (HEWL) at 20, 37 and 55 °C in pure water were studied by UV-Vis absorption spectroscopy, intrinsic fluorescence and circular dichroism, dynamic and electrophoretic light scattering and inductively coupled plasma mass spectrometry. X-ray structures were also solved for the adducts formed at 20 and 55 °C. Data demonstrate that high temperature facilitates the formation of CDDP-HEWL adducts, where Pt atoms bind ND1 atom of His15 or NE2 atom of His15 and NH1 atom of Arg14. Our study suggests that high human body temperature (fever) could increase the rate of drug binding to proteins thus enhancing possible toxic side effects related to CDDP administration.

Analysis of the role of O-glycosylation in GH51 α-L-arabinofuranosidase from Pleurotus ostreatus

In this study, the recombinant α-L-arabinofuranosidase from the fungus Pleurotus ostreatus (rPoAbf) was subjected to site-directed mutagenesis with the aim of elucidating the role of glycosylation on the properties of the enzyme at the level of S160 residue. As a matter of fact, previous mass spectral analyses had led to the localization of a single O-glycosylation at this site. Recombinant expression and characterization of the rPoAbf mutant S160G was therefore performed. It was shown that the catalytic properties are slightly changed by the mutation, with a more evident modification of the Kcat and KM toward the synthetic substrate pN-glucopyranoside. More importantly, the mutation negatively affected the stability of the enzyme at various pHs and temperatures. Circular dichroism (CD) analyses showed a minimum at 210 nm for wild-type (wt) rPoAbf, typical of the beta-sheets structure, whereas this minimum is shifted for rPoAbf S160G, suggesting the presence of an unfolded structure. A similar behavior was revealed when wt rPoAbf was enzymatically deglycosylated. CD structural analyses of both the site-directed mutant and the enzymatically deglycosylated wild-type enzyme indicate a role of the glycosylation at the S160 residue in rPoAbf secondary structure stability.

Abstract LB-022: Aptamer-mediated inhibition of EGFRvIII mutant in glioblastoma cells

High-grade glioblastoma multiforme (GBM) is the most aggressive and common of gliomas in human populations, accounting for 55% of primary brain tumors. The prognosis of GBM is very poor and most patients die of tumor recurrence.

The epidermal growth factor receptor (EGFR) and the platelet-derived growth factor receptor β (PDGFRβ) are hallmarks in GBM since they influence multiple aspects of tumor biology including cell proliferation, migration, invasiveness and resistance to treatment. In approximately half of the tumors with amplified EGFR, the EGFRvIII truncated extracellular mutant is detected. EGFRvIII does not bind ligand, is highly oncogenic and appears to be relatively resistant to treatment with conventional anti-EGFR agents such as ligand blocking monoclonal antibodies or EGFR tyrosine kinase inhibitors (TKIs). Recently, it has been demonstrated that EGFRvIII-dependent cancers may escape targeted therapy by developing dependence on PDGFRβ signaling, thus providing a strong rationale for combination therapy aimed at blocking both EGFRvIII and PDGFRβ signaling.

We have generated two nuclease resistant 2′F-Py RNA aptamers, CL4 and Gint4.T, as high affinity ligands and inhibitors of human wild-type EGFR (EGFRwt) and PDGFRβ, respectively. Thanks to their unique characteristics (low size, good target affinity, no immunogenicity, high stability) aptamers represent a new class of molecules with a great potential to rival monoclonal antibodies in both therapy and diagnosis.

Herein, by different approaches we demonstrate that CL4 aptamer binds to the EGFRvIII mutant even though it lacks amino acids 6-273 in the extracellular domain. As a consequence of binding, the aptamer inhibits EGFRvIII activation by hampering receptor homodimerization and downstream STAT3 pathway, thus confirming the critical role of EGFRvIII dimerization for signaling. Further, we show that targeting EGFRvIII by CL4, as well as by erlotinib and gefitinib, causes upregulation of PDGFRβ as a compensatory response to support cancer cell survival. Importantly, CL4 and EGFRTKIs cooperate with the anti-PDGFRβ aptamer in inhibiting survival and proliferation of EGFRvIII-overexpressing glioblastoma cells.

Given the paucity of selective inhibitors for receptor tyrosine kinases, this study could have impact in the fields of targeted molecular cancer therapeutics and may result in progress against GBM.

Citation Format: Simona Camorani, Elvira Crescenzi, David Colecchia, Andrea Carpentieri, Angela Amoresano, Mario Chiariello, Laura Cerchia. Aptamer-mediated inhibition of EGFRvIII mutant in glioblastoma cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr LB-022. doi:10.1158/1538-7445.AM2015-LB-022

Cross-species toxicogenomic analyses and phenotypic anchoring in response to groundwater low-level pollution

Background

Comparison of toxicogenomic data facilitates the identification of deregulated gene patterns and maximizes health risk prediction in human.

Results

Here, we performed phenotypic anchoring on the effects of acute exposure to low-grade polluted groundwater using mouse and zebrafish. Also, we evaluated two windows of chronic exposure in mouse, starting in utero and at the end of lactation. Bioinformatic analysis of livers microarray data showed that the number of deregulated biofunctions and pathways is higher after acute exposure, compared to the chronic one. It also revealed specific profiles of altered gene expression in all treatments, pointing to stress response/mitochondrial pathways as major players of environmental toxicity. Of note, dysfunction of steroid hormones was also predicted by bioinformatic analysis and verified in both models by traditional approaches, serum estrogens measurement and vitellogenin mRNA determination in mice and zebrafish, respectively.

Conclusions

In our report, phenotypic anchoring in two vertebrate model organisms highlights the toxicity of low-grade pollution, with varying susceptibility based on exposure window. The overlay of zebrafish and mice deregulated pathways, more than single genes, is useful in risk identification from chemicals implicated in the observed effects.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-1067) contains supplementary material, which is available to authorized users.