Intranasal administration of insulin-like growth factor-1 protects against lipopolysaccharide-induced injury in the developing rat brain

Our previous studies show that insulin-like growth factor-1 (IGF-1) can either protect against or increase lipopolysaccharide (LPS)-induced damage in the developing brain, depending on the dose, when it is co-administered with LPS through intracerebral injection. To further explore effects of IGF-1 on central inflammation associated brain injury, IGF-1 was administered through intranasal infusion in the current study. Postnatal day 5 (P5) rats were exposed to LPS at a dose of 1 μg/g body weight or sterile saline through intracerebral injection. Recombinant human insulin-like growth factor-1 (rhIGF-1) at a dose of 50 μg/pup or vehicle was administered intranasally 1 or 2 h after the LPS injection. Neonatal LPS exposure resulted in oligodendrocyte (OL) and white matter injury in the P6 or P21 rat brain. The damages include dilatation of lateral ventricles, pyknotic cell death, loss of OL progenitor cells and mature OLs in the cingulum area, and impairment of myelination at the corpus callosum area. Neurological dysfunctions were observed in juvenile rats with neonatal LPS exposure. Intranasal IGF-1 treatment at either 1 or 2 h after LPS exposure significantly attenuated LPS-induced brain injury and improved some behavioral deficits. Intranasal IGF-1 treatment also reduced infiltration of polymorphonuclear (PMN) leukocytes and activation of microglia in the rat brain 24 h after LPS exposure, but it did not prevent the elevation in concentrations of interleukin-1β (IL-1β) and tumor necrosis factor alpha (TNFα) in the LPS-exposed rat brain during the first 24 h. This is an indication that direct anti-inflammation might not be the primary mechanism for the protection of IGF-1, and other mechanisms, such as anti-apoptotic effects, are likely involved in its protective effects.

The expression of histone demethylase JMJD1A in renal cell carcinoma

BACKGROUND

Hypoxia-inducible factor 1α has been shown to play a central role in RCC tumorigenesis by acting as a transcription factor. Histone demethylase JMJD1A is an iron- and 2-oxoglutarate-dependent dioxygenase which catalyze the demethylation of mono- and dimethylated H3K9. JMJD1A can be upregulated by hypoxia via HIF-1 and associated with cancer. The expression of JMJD1A was determined in 10 kidney cancer tissue and adjacent tissue by quantitative polymerase chain reaction, western blotting and immunohistochemistry. Furthermore, the expression of JMJD1A was investigated in cell line 786-0 through adding nickle or cobalt ion to mimic hypoxic environment. The expression of JMJD1A was higher in cancer tissue than adjacent tissue, and in hypoxic environment than normal environment. In cancer tissue, the JMJD1A mainly located around blood vessels which indicated that JMJD1A is involved tumor angiogenesis.

CONCLUSION

the increased expression of JMJD1A might be associated with the progression of kidney cancer.

KEYWORDS

renal cell carcinoma, histone demethylase, JMJD1A, hypoxia-inducible factor, iron.

Near tubule and intertubular bovine dentin mapped at the 250 nm level

In this study, simultaneous diffraction and fluorescence mapping with a (250nm)(2), 10.1keV synchrotron X-ray beam investigated the spatial distribution of carbonated apatite (cAp) mineral and elemental Ca (and other cations including Zn) around dentin tubules. In 1μm thick sections of near-pulp root dentin, where peritubular dentin (PTD) is newly forming, high concentrations of Zn, relative to those in intertubular dentin (ITD), were observed adjacent to and surrounding the tubule lumens. Some but not all tubules exhibited hypercalcified collars (high Ca signal relative to the surrounding ITD), and, when present, the zone of high Ca did not extend around the tubule. Diffraction rings from cAp 00.2 and 11.2+21.1+30.0 reflections were observed, and cAp was the only crystal phase detected. Profiles of Ca, Zn and cAp diffracted intensities showed the same transitions from solid to tubule lumen, indicating the same cAp content and organization in ITD far from the tubules and adjacent to them. Further, the matching Ca and diffraction profiles demonstrated that all of the Ca is in cAp or that any noncrystalline Ca was uniformly distributed throughout the dentin. Variation of 00.2 and 11.2+21.1+30.0 diffracted intensity was consistent with the expected biaxial crystallographic texture. Extension of X-ray mapping from near 1μm resolution to the 250nm level, performed here for dentin and its tubules, will provide new understanding of other mineralized tissues.

IDH1 and IDH2 mutations in pediatric acute leukemia

To investigate the frequency of isocitrate dehydrogenase 1 (IDH1) and 2 (IDH2) mutations in pediatric acute myeloid leukemia (AML) and acute lymphoid leukemia (ALL), we sequenced these genes in diagnostic samples from 515 patients (227 AMLs and 288 ALLs). Somatic IDH1/IDH2 mutations were rare in ALL (N=1), but were more common in AML, occurring in 3.5% (IDH1 N=3 and IDH2 N=5), with the frequency higher in AMLs with a normal karyotype (9.8%). The identified IDH1 mutations occurred in codon 132 resulting in replacement of arginine with either cysteine (N=3) or histidine (N=1). By contrast, mutations in IDH2 did not affect the homologous residue but instead altered codon 140, resulting in replacement of arginine with either glutamine (N=4) or tryptophan (N=1). Structural modeling of IDH2 suggested that codon 140 mutations disrupt the enzyme's ability to bind its substrate isocitrate. Accordingly, recombinant IDH2 R140Q/W were unable to carry out the decarboxylation of isocitrate to α-ketoglutarate (α-KG), but instead gained the neomorphic activity to reduce α-KG to R(-)-2-hydroxyglutarete (2-HG). Analysis of primary leukemic blasts confirmed high levels of 2-HG in AMLs with IDH1/IDH2 mutations. Interestingly, 3/5 AMLs with IDH2 mutations had FLT3-activating mutations, raising the possibility that these mutations cooperate in leukemogenesis.

Developmental expression of ACRV1 in humans and mice

To identify the developmental expression of the ACRV1 gene in humans and mice, testes cDNA samples were collected at different post-natal days (days 4, 9, 18, 35, 54, and 6 months) from Balb/c mice and were hybridised to the mouse whole genome 430 2.0 Array (Affymetrix Inc.) chip. The characteristics of ACRV1 were analysed using various cellular and molecular biotechnologies. The results showed that the expression of mouse ACRV1 was not detected in mouse testes on days 4, 9, and 18 but was present on days 35, 54, and 6 months. Using RT-PCR analysis of mouse ACRV1, we determined that mouse ACRV1 was expressed specifically in the mouse testis, and its expression began at days 35. Western blot analysis demonstrated that human ACRV1 was primarily expressed in human testes, and immunofluorescent and immunohistochemistry staining showed that human ACRV1 protein was predominantly located in round and elongated spermatids in human testes, indicating that ACRV1 may play an important role in mammalian spermatogenesis and may be a target of a contraceptive vaccine.

Abstract P1-03-06: Population Based In Vivo Biomarker Discovery Using Engineered Human Tumors

Background:

Tumors from patients exhibit significant inter-tumor variation, where each tumor harbors a unique set of genetic alterations that impact prognosis and response to treatment. Unfortunately, this variation contributes to low response rates in the clinic and creates significant challenges for treating patients with appropriate drugs. Cancer cell line based xenografts have traditionally been the preclinical model of choice to assess the efficacy of clinical compounds; however, such in vitro models exhibit inherent artifacts, and are unable to adequately capture natural variation seen in human tumor populations. It has therefore become a priority in oncology and personalized medicine to match patients to drugs that will result in a favorable treatment outcome. In this report, we describe a population based approach for response prediction featuring naturally occurring variation in tumors derived from genetically defined human-in-mouse models of cancer. Materials and Methods:

A population of De novo human breast tumors were generated by genetically engineering normal primary human breast epithelial cells with HER2 and SV40 early region (HER2/SV40er) or KRAS and SV40 early region (KRAS/SV40er) in an in vivo Human-In-Mouse (HIM) tissue transgenic model (Wu et al, Proc Natl Acad Sci U S A 2009, 106: 7022-2027). Each tumor of the population has been comprehensively characterized histopathologically, and at the RNA and DNA level. Furthermore, the population has been adapted to conduct quantitative efficacy studies of anti-cancer agents and combinations. Results:

The HER2/SV40er and the KRAS/SV40er HIM tumors develop as invasive human breast adenocarcinoma that are histologically similar to those observed in patients. Microarray and CGH profiling demonstrated significant inter-tumor variation among the established tumors, as has been reported for patient tumors. Moreover, the KRAS/SV40er tumors clustered with basal type breast cancers from patients, a poor prognosis human breast cancer subtype. Both HER2/SV40er and KRAS/SV40er tumors exhibited variable responses to treatments with the potent selective triple VEGFR inhibitor, tivozanib. Further characterization of those tumors, both pre-and post-treatment, identified potential biomarkers for tumor response to tivozanib. Discussion:

The genetically defined human-in-mouse tumors exhibited natural variations similar to that occurs in human cancer. This population-based HIM system enables us to identify and validate biomarkers of therapeutic response in an in vivo human tumor model. Figure available in online version.

Excitation mapping of whispering gallery modes in silica microcavities

We report the direct observation of the electromagnetic-field distribution of whispering gallery modes in silica microcavities (spheres and toroids). It is revealed by their excitation efficiency with a tapered fiber coupler swept along the meridian. The originality of this method lies in the use of the coupler itself for the near-field mapping, eliminating the need of additional tools used in previous work. This method is successfully applied to microspheres and microtoroids.

Lipopolysaccharide-activated microglia induce death of oligodendrocyte progenitor cells and impede their development

Damage to oligodendrocyte (OL) progenitor cells (OPCs) and hypomyelination are two hallmark features of periventricular leukomalacia (PVL), the most common form of brain damage in premature infants. Clinical and animal studies have linked the incidence of PVL to maternal infection/inflammation, and activated microglia have been proposed to play a central role. However, the precise mechanism of how activated microglia adversely affects the survival and development of OPCs is still not clear. Here we demonstrate that lipopolysaccharide (LPS)-activated microglia are deleterious to OPCs, that is, impeding OL lineage progression, reducing the production of myelin basic protein (MBP), and mediating OPC death. We further demonstrate that LPS-activated microglia mediate OPC death by two distinct mechanisms in a time-dependent manner. The early phase of cell damage occurs within 24 h after LPS treatment, which is mediated by nitric oxide (NO)-dependent oxidative damage and is prevented by N(G)-nitro-l-arginine methyl ester (l-NAME), a general inhibitor of nitric oxide synthase. The delayed cell death is evident at 48 h after LPS treatment, is mediated by cytokines, and is prevented by blocking the activity of tumor necrosis factor-alpha (TNF-alpha) and pro-nerve growth factor (proNGF), but not by l-NAME. Furthermore, microglia-derived insulin-like growth factor-1 (IGF-1) and ciliary neurotrophic factor (CNTF) were significantly suppressed by LPS, and exogenous IGF-1 and CNTF synergistically protected OLs from death induced by LPS-treated microglia conditioned medium, indicating that a deficiency in trophic support may also be involved in OL death. Our finding that LPS-activated microglia not only induce two waves of cell death but also greatly impair OL development may shed some light on the mechanisms underlying selective white matter damage and hypomyelination in PVL.

Cyclin D1 as a universally expressed mantle cell lymphoma-associated tumor antigen for immunotherapy

Mantle cell lymphoma (MCL) accounts for 5-10% of all non-Hodgkin lymphomas and has the worst prognosis among all lymphomas. The hallmark of MCL is a t(11;14) translocation that results in overexpression of cyclin D1 by tumor cells of virtually all patients. In this study, we examined whether cyclin D1 could be an effective tumor-associated antigen for immunotherapy. We identified cyclin D1 peptides for HLA-A(*)0201 and generated peptide-specific CD8(+) T-cell lines from HLA-A(*)0201(+) blood donors and MCL patients. These cell lines proliferated in response to cyclin D1 peptide-pulsed stimulatory cells. Moreover, the T cells efficiently lysed peptide-pulsed but not unpulsed T2 cells and autologous dendritic cells; cyclin D1(+) and HLA-A(*)0201(+) human MCL lines MINO, SP53, Jeko-1 and Granta 519; and more importantly, HLA-A(*)0201(+) primary lymphoma cells from MCL patients. No killing was observed with HLA-A(*)0201(-) primary lymphoma cells or HLA-A(*)0201(+) normal blood cells, including B cells. These results indicate that these T cells are potent cytotoxic T cells and recognize cyclin D1 peptides naturally presented by patient lymphoma cells in the context of HLA-A(*)0201 molecules. Taken together, our work identifies cyclin D1 as a potentially important antigen for immunotherapy of MCL.

Selective Vulnerability of Peripheral Nerves in Avian Riboflavin Deficiency Demyelinating Polyneuropathy

Riboflavin (vitamin B2) deficiency in young chickens produces a demyelinating peripheral neuropathy. In this study, day-old broiler meat chickens were fed a riboflavin-deficient diet (1.8 mg/kg) and killed on posthatch days 6, 11, 16, 21, and 31, while control chickens were given a conventional diet containing 5.0 mg/kg riboflavin. Pathologic changes were found in sciatic, cervical, and lumbar spinal nerves of riboflavin-deficient chickens from day 11 onwards, characterized by endoneurial oedema, hypertrophic Schwann cells, tomacula (redundant myelin swellings), demyelination/remyelination, lipid deposition, and fibroblastic onion bulb formation. Similar changes were also found in large and medium intramuscular nerves, although they were less severe in the latter. However, by contrast, ventral and dorsal spinal nerve roots, distal intramuscular nerves, and subcutaneous nerves were normal at all time points examined. These findings demonstrate, for the first time, that riboflavin deficiency in young, rapidly growing chickens produces selective injury to peripheral nerve trunks, with relative sparing of spinal nerve roots and distal nerve branches to muscle and skin. These novel findings suggest that the response of Schwann cells in peripheral nerves with riboflavin deficiency differs because either there are subsets of these cells in, or there is variability in access of nutrients to, different sites within the nerves.