Fatty acid binding protein 4 (FABP4) plays an important role in maintaining glucose and lipid homeostasis. FABP4 has been primarily regarded as an adipocyte- and macrophage-specific protein, but recent studies suggest that it may be more widely expressed. We found strong FABP4 expression in the endothelial cells (ECs) of capillaries and small veins in several mouse and human tissues, including the heart and kidney. FABP4 was also detected in the ECs of mature human placental vessels and infantile hemangiomas, the most common tumor of infancy and ECs. In most of these cases, FABP4 was detected in both the nucleus and cytoplasm. FABP4 mRNA and protein levels were significantly induced in cultured ECs by VEGF-A and bFGF treatment. The effect of VEGF-A on FABP4 expression was inhibited by chemical inhibition or short-hairpin (sh) RNA-mediated knockdown of VEGF-receptor-2 (R2), whereas the VEGFR1 agonists, placental growth factors 1 and 2, had no effect on FABP4 expression. Knockdown of FABP4 in ECs significantly reduced proliferation both under baseline conditions and in response to VEGF and bFGF. Thus, FABP4 emerged as a novel target of the VEGF/VEGFR2 pathway and a positive regulator of cell proliferation in ECs.
Despite advances in the understanding of its molecular pathophysiology, pancreatic cancer remains largely incurable, highlighting the need for novel therapies. We developed a chimeric antigen receptor (CAR) specific for prostate stem cell antigen (PSCA), a glycoprotein that is overexpressed in pancreatic cancer starting at early stages of malignant transformation. To optimize the CAR design, we used antigen-recognition domains derived from mouse or human antibodies, and intracellular signaling domains containing one or two T cell costimulatory elements, in addition to CD3zeta. Comparing multiple constructs established that the CAR based on human monoclonal antibody Ha1-4.117 had the greatest reactivity in vitro. To further analyze this CAR, we developed a human pancreatic cancer xenograft model and adoptively transferred CAR-engineered T cells into animals with established tumors. CAR-engineered human lymphocytes induced significant antitumor activity, and unlike what has been described for other CARs, a second-generation CAR (containing CD28 cosignaling domain) induced a more potent antitumor effect than a third-generation CAR (containing CD28 and 41BB cosignaling domains). While our results provide evidence to support PSCA as a target antigen for CAR-based immunotherapy of pancreatic cancer, the expression of PSCA on selected normal tissues could be a source of limiting toxicity.
The single dose pharmacokinetics of olanzapine in rats, following an oral dose and its distribution in the brain and other tissues after repeated oral and intra-peritoneal (i.p.) administration, were studied. Olanzapine in plasma, brain, liver, lung, kidney, spleen and fat was assayed at predose, 0.25, 0.5, 1, 2, 5, 12, 24, 36, 48 h postoral dose of 6 mg/kg and after daily oral and i.p. doses of 0.25, 1, 3, and 6 mg/kg/day of olanzapine for 15 consecutive days by a sensitive and specific HPLC method with electrochemical detection. Olanzapine was readily absorbed and distributed in plasma and tissues as the peak concentrations were reached within approximately 45 min after the oral dose. The terminal half-life of olanzapine in plasma was 2.5 h and in tissues it ranged from 3 to 5.2 h. The area under the concentration-time curve (AUC(last)) was lowest in plasma and largest in liver and lung. The AUC(last) of olanzapine was eight times larger in brain and three to 32 times larger in other tissues than that in plasma. After repeated oral doses, the plasma and tissue concentrations of olanzapine were generally higher than those after repeated i.p. doses. The liver and spleen had the highest concentrations after oral and i.p doses, respectively. In both cases, the tissue concentrations were four- to 46-fold higher than that in plasma and correlated with administered doses. Likewise, plasma concentrations strongly correlated with the simultaneous brain and tissue concentrations (r(2)>0.908, p<0.0001). On average, the brain levels were 6.3-13.1 and 5.4-17.6 times higher than the corresponding plasma level after oral and i.p. doses, respectively. The tissue to plasma level ratio of olanzapine was higher in other tissues. The data indicated that olanzapine is rapidly absorbed and widely distributed in the tissues of rats after oral and i.p. administration. The plasma concentration appears to predict the simultaneous concentration in brain and other tissues. There was no marked localized accumulation of olanzapine in any of the regions of the rat brain.
We generated a mouse line harboring an autosomal-dominant nocturnal frontal lobe epilepsy (ADNFLE) mutation: the ␣4 nicotinic receptor S248F knock-in strain. In this mouse, modest nicotine doses (1-2 mg/kg) elicit a novel behavior termed the dystonic arousal complex (DAC). The DAC includes stereotypical head movements, body jerking, and forelimb dystonia; these behaviors resemble some core features of ADNFLE. A marked Straub tail is an additional component of the DAC. Similar to attacks in ADNFLE, the DAC can be partially suppressed by the sodium channel blocker carbamazepine or by pre-exposure to a very low dose of nicotine (0.1 mg/kg). The DAC is centrally mediated, genetically highly penetrant, and, surprisingly, not associated with overt ictal electrical activity as assessed by (1) epidural or frontal lobe depth-electrode electroencephalography or (2) hippocampal c-fos-regulated gene expression. Heterozygous knock-in mice are partially protected from nicotine-induced seizures. The noncompetitive antagonist mecamylamine does not suppress the DAC, although it suppresses high-dose nicotine-induced wild-type-like seizures. Experiments on agonist-induced 86 Rb ϩ and neurotransmitter efflux from synaptosomes and on ␣4S248F2 receptors expressed in oocytes confirm that the S248F mutation confers resistance to mecamylamine blockade. Genetic background, gender, and mutant gene expression levels modulate expression of the DAC phenotype in mice. The S248F mouse thus appears to provide a model for the paroxysmal dystonic element of ADNFLE semiology. Our model complements what is seen in other ADNFLE animal models. Together, these mice cover the spectrum of behavioral and electrographic events seen in the human condition.Key words: nicotine; epilepsy; ADNFLE; dystonia; mecamylamine; synaptosome IntroductionNocturnal frontal lobe epilepsy (NFLE) is characterized by clusters of stereotypic episodes of arousal from sleep associated with dystonic neck, limb, and trunk movements that occur during stages 2-4 of non-rapid eye movement (REM) sleep (Montagna, 1992;Plazzi et al., 1995;Provini et al., 1999;Provini et al., 2000).Less commonly, there are prolonged ballistic limb and trunk movements, resulting in injury Combi et al., 2004). Autosomal-dominant NFLE (ADNFLE) , a familial subtype of NFLE, was initially associated with a missense (S248F) mutation in the ␣4 nicotinic acetylcholine receptor subunit (␣4-nAChR) gene (Steinlein et al., 1995) at position 6Ј in the M2 transmembrane region. Subsequently, in other ADNFLE pedigrees, additional mutations were discovered at the ␣4 M2-10Ј (Steinlein et al., 1997;Hirose et al., 1999), M2-17Ј (Steinlein et al., 1997;Hirose et al., 1999), and 2 subunit M2-22Ј positions and one at the 2 M3 position that contacts M2 in most structural models (De Fusco et al., 2000;Phillips et al., 2001;Bertrand et al., 2005). A mutation in ␣2 (Aridon et al., 2006) was identified in a pedigree with atypical nocturnal epilepsy.Electrophysiological analyses of heterologously expressed ADNFLE alleles sugge...
Metastasis remains a leading cause of cancer mortality due to the lack of specific inhibitors against this complex process. To identify compounds selectively targeting the metastatic state, we used the perinuclear compartment (PNC), a complex nuclear structure associated with metastatic behaviors of cancer cells, as a phenotypic marker for a high-content screen of over 140,000 structurally diverse compounds. Metarrestin, obtained through optimization of a screening hit, disassembles PNCs in multiple cancer cell lines, inhibits invasion in vitro, blocks metastatic development in three mouse models of human cancer, and extends survival of mice in a metastatic pancreatic cancer xenograft model with no organ toxicity or discernable adverse effects. Metarrestin disrupts the nucleolar structure and inhibits RNA polymerase (Pol) I transcription, at least in part by interacting with the translation elongation factor eEF1A2. Altogether, metarrestin represents a potential therapeutic approach for the treatment of metastatic cancer.
Huntington's disease is characterized by death of striatal projection neurons. We used a Cre/Lox transgenic approach to generate an animal model in which D1 dopamine receptor (Drd1a)؉ cells are progressively ablated in the postnatal brain. Striatal Drd1a, substance P, and dynorphin expression is progressively lost, whereas D2 dopamine receptor (Drd2) and enkephalin expression is up-regulated. Magnetic resonance spectroscopic analysis demonstrated early elevation of the striatal choline/creatine ratio, a finding associated with extensive reactive striatal astrogliosis. Sequential MRI demonstrated a progressive reduction in striatal volume and secondary ventricular enlargement confirmed to be due to loss of striatal cells. Mutant mice had normal gait and rotarod performance but displayed hindlimb dystonia, locomotor hyperactivity, and handling-induced electrographically verified spontaneous seizures. Ethological assessment identified an increase in rearing and impairments in the oral behaviors of sifting and chewing. In line with the limbic seizure profile, cell loss, astrogliosis, microgliosis, and down-regulated dynorphin expression were seen in the hippocampal dentate gyrus. This study specifically implicates Drd1a؉ cell loss with tail suspension hindlimb dystonia, hyperactivity, and abnormal oral function. The latter may relate to the speech and swallowing disturbances and the classic sign of tongueprotrusion motor impersistence observed in Huntington's disease. In addition, the findings of this study support the notion that Drd1a and Drd2 are segregated on striatal projection neurons. striatum ͉ Cre ͉ Huntington's disease T he nigrostriatal pathway projects from the midbrain substantia nigra pars compacta to innervate the dorsal striatum. Dopamine is released from dopaminergic terminals in the striatum to regulate motor activity and eating behavior (1). Early studies suggested that dopamine D1 (Drd1a) and D2 receptors (Drd2) are segregated on striatal projection neurons; the Drd1a is expressed on substance P and dynorphin-positive striatal neurons, which project directly to the substantia nigra pars reticulata/entopeduncular complex (known as the direct pathway), whereas Drd2 is preferentially expressed on enkephalin-positive striatopallidal projecting neurons (2). Neurons within the globus pallidus then project to the subthalamic nucleus, which in turn relays to the substantia nigra pars reticulata/entopeduncular complex (known as the indirect pathway). Dopamine also modulates the activity of glutamatergic corticostriatal input on striatal projection neurons.Idiopathic Parkinson's disease is characterized by the death of dopaminergic neurons; however, rare Parkinsonian syndromes have been identified in which the defect is associated with cell death in the dopamine-responsive neurons in the striatum (3-6). Huntington's disease (HD) (7-10), a neurodegenerative condition with motor, cognitive, and psychiatric disturbances, also involves death of dopamine receptor-expressing striatal projection neurons. Several ...
Pancreatic cancer remains an incurable condition. Its progression is driven, in part, by subsets of cancer cells that evade the cytotoxic effects of conventional chemotherapies. These cells are often low-cycling, multidrug resistant, and adopt a stem cell-like phenotype consistent with the concept of cancer stem cells (CSC). To identify drugs impacting on tumor-promoting CSCs, we performed a differential high-throughput drug screen in pancreatic cancer cells cultured in traditional (2D) monolayers versus threedimensional (3D) spheroids which replicate key elements of the CSC model. Among the agents capable of killing cells cultured in both formats was a 1H-benzo[d]imidazol-2amine-based inhibitor of IL2-inducible T-cell kinase (ITK; NCGC00188382, inhibitor #1) that effectively mediated growth inhibition and induction of apoptosis in vitro, and suppressed cancer progression and metastasis formation in vivo. An examination of this agent's polypharmacology via in vitro and in situ phosphoproteomic profiling demonstrated an activity profile enriched for mediators involved in DNA damage repair. Included was a strong inhibitory potential versus the thousand-and-one amino acid kinase 3 (TAOK3), CDK7, and aurora B kinases. We found that cells grown under CSC-enriching spheroid conditions are selectively dependent on TAOK3 signaling. Loss of TAOK3 decreases colony formation, expression of stem cell markers, and sensitizes spheroids to the genotoxic effect of gemcitabine, whereas overexpression of TAOK3 increases stem cell traits including tumor initiation and metastasis formation. By inactivating multiple components of the cell-cycle machinery in concert with the downregulation of key CSC signatures, inhibitor #1 defines a distinctive strategy for targeting pancreatic cancer cell populations.
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