FLT3-targeted therapy restores GATA1 pathway function in NPM1/FLT3-ITD mutated acute myeloid leukaemia.

One-third of newly diagnosed adult acute myeloid leukaemia (AML) carry FLT3 mutations, which frequently occur together with nucleophosmin (NPM1) mutations and are associated with worse prognosis. FLT3 inhibitors are widely used in clinics with limitations due to drug resistance. AML cells carrying FLT3 mutations in both mouse models and patients present low expression of GATA1, a gene involved in haematopoietic changes preceding AML. Here, we show that FLT3 inhibition induces cellular responses and restores the GATA1 pathway and functions in NPM1/FLT3-ITD mutated AML, thus providing a new mechanism of action for this drug.

Validation of an LC-MS/MS method for the quantification IOA-289 in human plasma and its application in a first-in-human clinical trial.

IOA-289 is a novel small molecule inhibitor of autotaxin developed as a first-in-class therapy of fibrotic pathologies including cancer. A method for quantitation of IOA-289 in human plasma was developed using a stable isotope labeled compound ([13C4]IOA-289) as internal standard. The analytes were extracted from human plasma by protein precipitation and the analysis was performed by liquid chromatography coupled with tandem mass spectrometric detection (LCMS/MS). The chromatographic separation was performed with a gradient elution from a BEH C18 column and under these conditions the retention time and the run time were 1 and 2 min, respectively. The assay was fully validated over the range 3-3000 ng/mL, proved to be accurate, precise and selective and was successfully applied to quantitate IOA-289 in plasma samples from subjects in a first-in-humanclinical trial.

Liquid chromatography-tandem mass spectrometry for the simultaneous quantitation of enmetazobactam and cefepime in human plasma.

A simple ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated for the simultaneous analysis enmetazobactam (also known as AAI101) and cefepime in human plasma. Sample preparation was based on protein precipitation with acetonitrile. Separation was performed on Acquity BEH HILIC column (50 mm × 2.1 mm, 1.7 µm) with a mobile phase containing ammonium formate in water and acetonitrile. The analytes were analyzed with the corresponding isotopically labeled internal standards and were detected in multiple reactions monitoring (MRM) using API 5000 triple-quadrupole mass spectrometer with electrospray (ESI) source operating in positive ion mode. The calibration curves were linear over the selected ranges (r > 0.9970 for both analytes). The intra and inter-assay precision of the Quality Control samples showed CV ≤ 15% and the accuracy was within 85 and 115% in all cases for both compounds. The lower limit of quantification was 0.05 µg/mL for enmetazobactam and 0.5 µg/mL for cefepime.

Correction: SSRIs target prefrontal to raphe circuits during development modulating synaptic connectivity and emotional behavior.

This article was originally published under standard licence, but has now been made available under a [CC BY 4.0] license. The PDF and HTML versions of the paper have been modified accordingly.

SSRIs target prefrontal to raphe circuits during development modulating synaptic connectivity and emotional behavior.

Antidepressants that block the serotonin transporter, (Slc6a4/SERT), selective serotonin reuptake inhibitors (SSRIs) improve mood in adults but have paradoxical long-term effects when administered during perinatal periods, increasing the risk to develop anxiety and depression. The basis for this developmental effect is not known. Here, we show that during an early postnatal period in mice (P0-P10), Slc6a4/SERT is transiently expressed in a subset of layer 5-6 pyramidal neurons of the prefrontal cortex (PFC). PFC-SERT+ neurons establish glutamatergic synapses with subcortical targets, including the serotonin (5-HT) and GABA neurons of the dorsal raphe nucleus (DRN). PFC-to-DRN circuits develop postnatally, coinciding with the period of PFC Slc6a4/SERT expression. Complete or cortex-specific ablation of SERT increases the number of functional PFC glutamate synapses on both 5-HT and GABA neurons in the DRN. This PFC-to-DRN hyperinnervation is replicated by early-life exposure to the SSRI, fluoxetine (from P2 to P14), that also causes anxiety/depressive-like symptoms. We show that pharmacogenetic manipulation of PFC-SERT+ neuron activity bidirectionally modulates these symptoms, suggesting that PFC hypofunctionality has a causal role in these altered responses to stress. Overall, our data identify specific PFC descending circuits that are targets of antidepressant drugs during development. We demonstrate that developmental expression of SERT in this subset of PFC neurons controls synaptic maturation of PFC-to-DRN circuits, and that remodeling of these circuits in early life modulates behavioral responses to stress in adulthood.

Nicotinic receptors mediate stress-nicotine detrimental interplay via dopamine cells' activity.

Epidemiological studies report strong association between mood disorders and tobacco addiction. This high comorbidity requires adequate treatment but the underlying mechanisms are unknown. We demonstrate that nicotine exposure, independent of drug withdrawal effects, increases stress sensitivity, a major risk factor in mood disorders. Nicotine and stress concur to induce long-lasting cellular adaptations within the dopamine (DA) system. This interplay is underpinned by marked remodeling of nicotinic systems, causing increased ventral tegmental area (VTA) DA neurons' activity and stress-related behaviors, such as social aversion. Blocking ß2 or α7 nicotinic acetylcholine receptors (nAChRs) prevents, respectively, the development and the expression of social stress-induced neuroadaptations; conversely, facilitating α7 nAChRs activation specifically in the VTA promotes stress-induced cellular and behavioral maladaptations. Our work unravels a complex nicotine-stress bidirectional interplay and identifies α7 nAChRs as a promising therapeutic target for stress-related psychiatric disorders.

GABAB receptor cell-surface export is controlled by an endoplasmic reticulum gatekeeper.

Endoplasmic reticulum (ER) release and cell-surface export of many G protein-coupled receptors (GPCRs) are tightly regulated. For gamma-aminobutyric acid (GABA)B receptors of GABA, the major mammalian inhibitory neurotransmitter, the ligand-binding GB1 subunit is maintained in the ER by unknown mechanisms in the absence of hetero-dimerization with the GB2 subunit. We report that GB1 retention is regulated by a specific gatekeeper, PRAF2. This ER resident transmembrane protein binds to GB1, preventing its progression in the biosynthetic pathway. GB1 release occurs upon competitive displacement from PRAF2 by GB2. PRAF2 concentration, relative to that of GB1 and GB2, tightly controls cell-surface receptor density and controls GABAB function in neurons. Experimental perturbation of PRAF2 levels in vivo caused marked hyperactivity disorders in mice. These data reveal an unanticipated major impact of specific ER gatekeepers on GPCR function and identify PRAF2 as a new molecular target with therapeutic potential for psychiatric and neurological diseases involving GABAB function.

The absence of VGLUT3 predisposes to cocaine abuse by increasing dopamine and glutamate signaling in the nucleus accumbens.

Tonically active cholinergic interneurons (TANs) from the nucleus accumbens (NAc) are centrally involved in reward behavior. TANs express a vesicular glutamate transporter referred to as VGLUT3 and thus use both acetylcholine and glutamate as neurotransmitters. The respective roles of each transmitter in the regulation of reward and addiction are still unknown. In this study, we showed that disruption of the gene that encodes VGLUT3 (Slc17a8) markedly increased cocaine self-administration in mice. Concomitantly, the amount of dopamine (DA) release was strongly augmented in the NAc of VGLUT3(-/-) mice because of a lack of signaling by metabotropic glutamate receptors. Furthermore, dendritic spines and glutamatergic synaptic transmission on medium spiny neurons were increased in the NAc of VGLUT3(-/-) mice. Increased DA and glutamate signaling in the NAc are hallmarks of addiction. Our study shows that TANs use glutamate to reduce DA release and decrease reinforcing properties of cocaine in mice. Interestingly, we also observed an increased frequency of rare variations in SLC17A8 in a cohort of severe drug abusers compared with controls. Our findings identify VGLUT3 as an unexpected regulator of drug abuse.

EGFR, pMAPK, pAkt and PTEN status by immunohistochemistry: correlation with clinical outcome in HER2-positive metastatic breast cancer patients treated with trastuzumab.

BACKGROUND: In an attempt to identify markers of resistance to trastuzumab, we evaluated both the profiling of human epidermal growth factor receptor 2 (HER2)-positive tumor cells measuring the relative levels of EGFR, pMAPK, pAkt and PTEN and their correlations with clinical outcome in HER2-positive metastatic breast cancer patients treated with trastuzumab. PATIENTS AND METHODS: Tumor tissues for this retrospective analysis were available from 45 out of 76 patients with metastatic breast cancer treated from April 1999 to March 2006 with trastuzumab-based therapy at our Institution. Evaluations of EGFR, pMAPK, pAkt and PTEN status by immunohistochemistry (IHC) were carried out on all 45 tissue samples and their correlations with response to trastuzumab, incidence of central nervous system (CNS) metastases, time to progression (TTP), overall survival from diagnosis of breast cancer (OS1), from diagnosis of metastatic disease (OS2) and from the start of trastuzumab (OS3) were analyzed. RESULTS: We observed that TTP (P = 0.001) and median OS2 and OS3 were significantly longer in patients responsive to trastuzumab-based regimen compared with nonresponsive patients. EGFR, pMAPK, pAkt and PTEN status by IHC were not significantly associated with response to trastuzumab, TTP, overall survival (OS1, OS2, OS3) and CNS metastases incidence. A trend for shorter OS3 was observed for pMAPK-positive patients compared with pMAPK-negative patients (22.8 versus 31.2 months; P = 0.076). Median OS1 resulted shorter in 22 pAkt-positive patients (69.8 months) compared with 23 pAkt-negative patients (108.2 months); P = 0.091. It is likely that high expression of pMAPK (pMAPK-positive status) or pAkt (pAkt-positive status) could identify a subgroup of HER2-positive tumors with high activity of proliferation and survival pathways and with resistance to trastuzumab. CONCLUSIONS: In HER2-positive metastatic breast cancers, EGFR, pMAPK, pAkt and PTEN status evaluated by IHC was not significantly associated with response to trastuzumab, TTP, OS and CNS metastases incidence. However, HER2 status determined by IHC and/or FISH assays may not be sufficient to predict response to trastuzumab-based therapy.

High coexpression of both insulin-like growth factor receptor-1 (IGFR-1) and epidermal growth factor receptor (EGFR) is associated with shorter disease-free survival in resected non-small-cell lung cancer patients.

BACKGROUND: Insulin-like growth factor receptor-1 (IGFR-1) represents a novel molecular target in non-small-cell lung cancer (NSCLC). IGFR-1 and epidermal growth factor receptor (EGFR) activation is essential to mediate tumor cell survival, proliferation and invasion. We explored the correlation between IGFR-1 and EGFR, their relationship with clinicopathological parameters and their impact on outcome in resected stage I-III NSCLC patients. PATIENTS AND METHODS: Tumors from 125 surgical NSCLC patients were evaluated for IGFR-1 and EGFR expression by immunohistochemistry. Kaplan-Meier estimates of survival and time to recurrence were calculated for clinical variables and biologic markers using the Cox model for multivariate analysis. RESULTS: IGFR-1 protein overexpression was detected in 36.0% of NSCLC patients and was associated with larger tumor size (P = 0.04) but not with other clinical or biological characteristics. EGFR protein overexpression was observed in 55.2% of NSCLC, more frequently in squamous cell carcinoma (SCC) than non-SCC (63.7% versus 36.3%, chi(2) = 9.8, P = 0.001). IGFR-1 protein expression was associated with EGFR protein expression (P = 0.03). At the multivariate analysis, high coexpression of both IGFR-1 and EGFR was a significant prognostic factor of worse disease-free survival (DFS) (hazard ratio 2.51, P = 0.01). CONCLUSION: A statistically significant association was observed between high coexpression of both IGFR-1 and EGFR and worse DFS in early NSCLC patients.

Mechanisms of synaptic depression triggered by metabotropic glutamate receptors.

Glutamate, by activation of metabotropic receptors (mGluRs), can lead to a reduction of synaptic efficacy at many synapses. These forms of synaptic plasticity are referred to as long-term depression (mGluR-LTD). We will distinguish between mGluR-LTD induced by pre- or postsynaptic receptors and mGluR-LTD induced by the locus of the expression mechanism of the synaptic depression. We will also review recent evidence that mGluR-mediated responses themselves are subject to depression, which may constitute a form of metaplasticity.

Reproductive cloning, genetic engineering and the autonomy of the child: the moral agent and the open future.

Some authors have argued that the human use of reproductive cloning and genetic engineering should be prohibited because these biotechnologies would undermine the autonomy of the resulting child. In this paper, two versions of this view are discussed. According to the first version, the autonomy of cloned and genetically engineered people would be undermined because knowledge of the method by which these people have been conceived would make them unable to assume full responsibility for their actions. According to the second version, these biotechnologies would undermine autonomy by violating these people's right to an open future. There is no evidence to show that people conceived through cloning and genetic engineering would inevitably or even in general be unable to assume responsibility for their actions; there is also no evidence for the claim that cloning and genetic engineering would inevitably or even in general rob the child of the possibility to choose from a sufficiently large array of life plans.

Basis of the gabamimetic profile of ethanol.

This article summarizes the proceedings of a symposium held at the 2005 Research Society on Alcoholism meeting. The initial presentation by Dr. Wallner provided evidence that selected GABA(A) receptors containing the delta subunit display sensitivity to low intoxicating ethanol concentrations and this sensitivity is further increased by a mutation in the cerebellar alpha6 subunit, found in alcohol-hypersensitive rats. Dr. Mameli reported that ethanol affects gamma-aminobutyric acid (GABA) function by affecting neural circuits that influence GABA release. Dr. Parsons presented data from electrophysiological and microdialysis investigations that ethanol is capable of releasing GABA from presynaptic terminals. Dr. Morrow demonstrated that systemic ethanol increases neuroactive steroids in brain, the absence of which alters various functional responses to ethanol. Dr. Criswell presented evidence that the ability of ethanol to increase GABA was apparent in some, but not all, brain regions indicative of regional specificity. Further, Dr. Criswell demonstrated that neurosteroids alone and when synthesized locally by ethanol act postsynaptically to enhance the effect of GABA released by ethanol in a region specific manner. Collectively, this series of reports support the GABAmimetic profile of acutely administered ethanol being dependent on several specific mechanisms distinct from a direct effect on the major synaptic isoforms of GABA(A) receptors.

Animal rights, animal minds, and human mindreading.

Do non-human animals have rights? The answer to this question depends on whether animals have morally relevant mental properties. Mindreading is the human activity of ascribing mental states to other organisms. Current knowledge about the evolution and cognitive structure of mindreading indicates that human ascriptions of mental states to non-human animals are very inaccurate. The accuracy of human mindreading can be improved with the help of scientific studies of animal minds. However, the scientific studies do not by themselves solve the problem of how to map psychological similarities (and differences) between humans and animals onto a distinction between morally relevant and morally irrelevant mental properties. The current limitations of human mindreading-whether scientifically aided or not-have practical consequences for the rational justification of claims about which rights (if any) non-human animals should be accorded.

The expression pattern of four odorant-binding proteins in male and female silk moths, Bombyx mori.

Four recombinant odorant-binding proteins of Bombyx mori, pheromone-binding protein (PBP), general odorant-binding protein 1 (GOBP1), general odorant-binding protein 2 (GOBP2) and antennal binding protein X (ABPX), were expressed in E. coli and used to raise polyclonal antisera. Immunoblots of antennal homogenates showed that these antisera were specific. In Western blot analysis and immunocytochemical labelling experiments, the sera against recombinant PBP and GOBP2 of B. mori gave identical results as sera against native PBP and GOBP2 of Antheraea polyphemus, respectively, thus confirming earlier results obtained with the latter. Labelling consecutive cross sections of various sensillum types with all four antisera revealed different labelling patterns in male and female sensilla (s.) trichodea and s. basiconica. Long s. trichodea in males and females represented uniform labelling types, whereas for short s. trichodea, s. intermedia, and s. basiconica a great variety of labelling patterns was observed, some being more common than others. Long s. trichodea, which in males are uniformly tuned to the pheromone components bombykol and bombykal, all strongly expressed PBP; labelling with antisera against the other three odorant-binding proteins hardly was above background, only in some hairs GOBP1 was expressed somewhat more strongly. Long s. trichodea of females, which respond specifically to linalool and benzoic acid, showed a different labelling pattern. Here, we observed strong labelling with antibodies against GOBP2 and medium labelling with anti-GOBP1, sometimes with anti-ABPX. S. basiconica in both sexes most commonly co-expressed GOBP1 and GOBP2, but other patterns were occasionally found, with some of them showing PBP expression, also in females. The great variety of labelling types in short s. trichodea, s. intermedia, and s. basiconica suggests a similar variety of functional subtypes as observed in plant odour-sensitive sensilla of other moth species.

Biphasic effects of NMDA on the motility of the rat portal vein.

The effect of NMDA on the motility of the rat portal vein was studied in an isolated preparation. NMDA induced a concentration-dependent (10(-7) - 10(-4) M) increase of the contraction frequency (maximum increase, 148+/-6% of control at NMDA 10(-4) M). The NMDA-induced excitatory response was prevented by the competitive NMDA receptor antagonists (+/-)-2-Amino-5-phosphonopentanoic acid (AP-5, 5x10(-4) M) or (RS)-3-(2-carboxypiperazine-4-yl) propyl-1-phosphonic acid (CPP, 10(-4) M). Tetrodotoxin (TTX, 10(-6) M) or atropine (10(-4) M) abolished the NMDA-induced increase of the portal vein motility and reversed the excitatory effect to a concentration-dependent inhibition (maximum inhibition, 52+/-8 and 29+/-7% of controls, respectively, at NMDA 10(-3) M). Removal of the endothelium abolished the NMDA-induced inhibitory response. Sodium nitroprusside concentration-dependently (10(-7) - 10(-5) M) inhibited the portal vein motility, while L-N(G)-nitro-arginine methyl ester (L-NAME, 10(-4) M) reversed the inhibitory effect of NMDA (in the presence of TTX), restoring the portal vein spontaneous activity to control values. These results show that NMDA modulates the portal vein motility in a biphasic manner: via indirect activation, through prejunctional NMDA receptors presumably located on intrinsic excitatory neuronal afferences, or via direct inhibition, through endothelial NMDA receptors activating the nitric oxide pathway. Overall these findings support the hypothesis of the existence of a peripheral glutamatergic innervation modulating the contractile activity of the rat portal vein. British Journal of Pharmacology (2000) 129, 156 - 162

An advantageous method to evaluate IgH rearrangement and its role in minimal residual disease detection.

A sensitive, safe and cheap method to detect minimal residual disease (MRD) is here presented. The PCR-GS technique includes: (a) a fluorescent PCR for the IgH region with CDR3/JH consensus primers; (b) the electrophoresis on an automatic sequencer (ABI PRISM 310); (c) the analysis of results by the GeneScan program. A total of 72 samples were analysed: 34/49 B-cell Non-Hodgkin's Lymphoma (NHL) (69%), six out of seven Multiple Myeloma (MM) (86%), 1/2 Hodgkin's Disease (HD) and 4/4 Acute Lymphoblastic Leukaemia (ALL) were found to be positive, showing a monoclonal IgH rearrangement. The major bias of the PCR-GS method are the 21% of false negatives, but 13/15 negative patients carried t(14;18); consequently, the association of the evaluation by PCR assays of the IgH and BCL2/JH rearrangement allowed to detect a molecular marker of B-neoplasia in more than 94% of tested samples.

Effect of resveratrol and some other natural compounds on tyrosine kinase activity and on cytolysis.

Resveratrol is a phytoalexin with several biological and pharmacological activities including the "French paradox". We investigated the effect of resveratrol on cytolytic activity by oxygen reactive species and on soluble and particulate tyrosine kinases from human placenta and human prostatic adenoma. These effects were compared with those of piceatannol, quercetin, catechin and epicatechin. Fifty percent of erythrocyte lysis due to H2O2-lactoperoxidase-KI incubation, in which I3-, OI- and oxygen singlet are produced, was obtained after 22 +/- 7 (SD) min in the absence of the tested compounds. The 50% lysis was obtained after 66 +/- 15, 129 +/- 35, 196 +/- 21, 240 +/- 63 and 420 +/- 80 min with 40 microM piceatannol, quercetin, resveratrol, epicatechin and catechin respectively. Protection was concentration dependent. The assay of tyrosine kinase activity was performed using two different substrates as follows: substrate A corresponded to the sequence 1-17 of gastrin, and substrate B to sequence 6-20 of cell division kinase p34cdc2. In all experiments, initial velocity was measured. When assayed with both substrates, tyrosine kinase activities from particulate and cytosolic fractions of placenta were more inhibited by piceatannol and quercetin. Resveratrol significantly inhibited the particulate fraction and the cytosolic fraction respectively when substrates A and B were employed: Catechin acted as an inhibitor with substrate A and particulate fraction while in the other experimental conditions it acted as an activator. Resveratrol inhibited the tyrosine kinase of particulate and cytosolic fractions of prostatic adenoma assayed with substrate A and B.

Total intravenous anaesthesia in Charcot-Marie-Tooth disease. Case report.

A Total Intravenous Anaesthesia (TIVA) protocol in a case of hereditary motor-sensory neuropathy Charcot-Marie-Tooth disease in three consecutive orthopaedic surgical procedures is described. History, physical examination and sural nerve fascicular biopsy findings are reported. Problems related to the perioperative anaesthesiological management in peripheral neuropathies are discussed. Propofol and fentanyl without muscle relaxants, proved to be a safe technique, fast at reaching the level of surgical anaesthesia required, manageable for maintenance and rapidly reversible.