Polymorphisms in innate immunity genes and patients response to dendritic cell-based HIV immuno-treatment

Dendritic cells (DCs)-based vaccine was demonstrated to increase HIV specific cellular immune response; however, in some HIV-infected patients, the response to the vaccine resulted to be not effective. In order to understand if the outcome of the vaccination may be influenced by the host`s genome and natural immunity, we studied the innate immune genome of HIV-infected patients previously vaccinated with DCs. We identified 15 SNPs potentially associated with the response to the immuno-treatment and two SNPs significantly associated with the modulation of the response to the DC vaccine: MBL2 rs10824792 and NOS1 rs693534. These two SNPs were also studied in different ethnic groups (Brazilians, African and Caucasian) of HIV-infected, exposed uninfected and unexposed uninfected subjects. The HIV positive Caucasian patients were also characterized by different disease progressions. Our findings suggest that, independently and/or in addition to other variables. the host`s genome could significantly contribute to the modulation of the response to the DC vaccine. (C) 2009 Elsevier Ltd. All rights reserved.

Erection induced by Tx2-6 toxin of Phoneutria nigriventer spider: Expression profile of genes in the nitric oxide pathway of penile tissue of mice

The peptides Tx2-5 and Tx2-6, isolated from the whole venom of ""armed-spider"" Phoneutria nigniventer venom, are directly linked with the induction of persistent and painful erection in the penis of mammals. The erection induced by Tx2-6 has been associated with the activation of nitric oxide synthases. There is a scarcity of studies focusing on the outcome of Tx2-6 at the molecular level, by this reason we evaluated the gene profile activity of this toxin at the nitric oxide (NO) pathway. After microarray analyses on cavernous tissue of mice inoculated with Tx2-6 we found that only 10.4% (10/96) of these genes were differentially expressed, showing a limited effect of the toxin on the NO pathway. We found the genes sparc, ednrb, junb, cdkn1a, bcl2, ccl5, abcc1 over-expressed and the genes sod1, s100a10 and fth1 under-expressed after inoculation of Tx2-6. The differential expressions of sparc and ednrb genes were further confirmed using real-time PCR. Interestingly, ednrb activates the L-arginine/NO/cGMP pathway that is involved in the relaxation of the cavernous body. Therefore the priapism induced by Tx2-6 is a consequence of a highly specific interference of this neurotoxin with the NO pathway. (C) 2009 Elsevier Ltd. All rights reserved.

De novo copy number variants identify new genes and loci in isolated sporadic tetralogy of Fallot

Tetralogy of Fallot (TOF), the most common severe congenital heart malformation, occurs sporadically, without other anomaly, and from unknown cause in 70% of cases. Through a genome-wide survey of 114 subjects with TOF and their unaffected parents, we identified 11 de novo copy number variants (CNVs) that were absent or extremely rare (<0.1%) in 2,265 controls. We then examined a second, independent TOF cohort (n = 398) for additional CNVs at these loci. We identified CNVs at chromosome 1q21.1 in 1% (5/512, P = 0.0002, OR = 22.3) of nonsyndromic sporadic TOF cases. We also identified recurrent CNVs at 3p25.1, 7p21.3 and 22q11.2. CNVs in a single subject with TOF occurred at six loci, two that encode known (NOTCH1, JAG1) disease-associated genes. Our findings predict that at least 10% (4.5-15.5%, 95% confidence interval) of sporadic nonsyndromic TOF cases result from de novo CNVs and suggest that mutations within these loci might be etiologic in other cases of TOF.

Genes Differentially Expressed in Prolactinomas Responsive and Resistant to Dopamine Agonists

Background/Aims: Prolactin (PRL) secretion and its gene expression are inhibited by dopamine. Prolactinomas are the most common secreting pituitary adenomas, and dopamine agonists (DA) are the first choice for their treatment. However, a subset of patients is resistant to DA. As the mechanisms involved in DA resistance are not fully understood, the aim of this study was to obtain new insights regarding the molecular differences between the prolactinomas that are responsive to DA and those that are resistant. Methods: Tumor tissue samples were collected from 17 patients who harbored prolactinomas, which were classified as responsive or resistant according to their clinical and laboratorial reaction to DA. The expression of 6 genes was evaluated by real-time polymerase chain reaction: dopamine receptor type 2 (DRD 2), nerve growth factor-beta (NGFB) and its receptor (NGFR), estrogen receptor-alpha (ERA), estrogen receptor-beta (ERB) and the pituitary tumor transforming gene (PTTG). Results: Median DRD 2 and NGFR expression in responsive patients was significantly higher than in resistant ones (p = 0.029 and p = 0.020, respectively). Moreover, the expressions of DRD 2 and NGFR were positively correlated with PRL decrease during treatment (r = 0.66, p = 0.005 and r = 0.57, p = 0.044, respectively). Furthermore, ERB expression was positively correlated to PTTG expression (r = 0.68, p = 0.032) and negatively correlated to NGFB expression (r = -0.75, p = 0.02). Conclusions: DRD2 and NGFR expressions are related to the responsiveness of prolactinoma to DA. However, PTTG, ERB and ERA expressions are not. Also ERB, ERA and PTTG expressions did not present a clear correlation to tumor aggressiveness. Furthermore, the response of prolactinomas to DA should be viewed as a spectrum ranging from the most responsive to the most resistant ones. Copyright (c) 2008 S. Karger AG, Basel

High numbers of human skin cancers express MMP2 and several integrin genes

Background: Basal cell carcinomas (BCC), squamous cell carcinomas (SCC) and cutaneous malignant melanoma (MM) are solid skin cancers derived from different cell types, with different ability to metastasize. Several subtypes of integrins and matrix metalloproteinases (MMP) have been related to malignization and metastasis processes. This work aimed at a quantitative evaluation of skin cancers expressing eight integrins and MMP2 genes. Methods: Expression of integrins and MMP2 genes was evaluated on fresh tumor biopsies from BCC, SCC and MM, and respective controls, by the reverse transcriptase polychain reaction (RT-PCR) technique. Results: More than 90% tumors expressed alpha 6a, beta 1, beta 3 and beta 6 (non-melanoma), and alpha 5a, alpha 6a and MMP2 (MM). Up to 100% controls also expressed beta 1 and beta 3. The results were significant for alpha 6a in BCC (p = 0.026), alpha 6b in SCC (p = 0.035), alpha 2a in BCC (p = 0.003), beta 5 and beta 6 in BCC (p = 0.005). MMP2 was expressed in 100% MM (p = 0.0004). Conclusion: Integrin subunits alpha 2a and alpha 6a would be interesting targets for BCC anti-tumor therapy, as well as alpha 6b in case of SCC. The elevated number of BCC expressing alpha 2 and alpha 6, and of MM expressing alpha v and MMP2, corroborate literature data.

Candidate-Gene Approach in Posttraumatic Stress Disorder After Urban Violence: Association Analysis of the Genes Encoding Serotonin Transporter, Dopamine Transporter, and BDNF

Posttraumatic stress disorder (PTSD) is a prevalent, disabling anxiety disorder marked by behavioral and physiologic alterations which commonly follows a chronic course. Exposure to a traumatic event constitutes a necessary, but not sufficient, factor. There is evidence from twin studies supporting a significant genetic predisposition to PTSD. However, the precise genetic loci still remain unclear. The objective of the present study was to identify, in a case-control study, whether the brain-derived neurotrophic factor (BDNF) val66met polymorphism (rs6265), the dopamine transporter (DAT1) three prime untranslated region (3`UTR) variable number of tandem repeats (VNTR), and the serotonin transporter (5-HTTPRL) short/long variants are associated with the development of PTSD in a group of victims of urban violence. All polymorphisms were genotyped in 65 PTSD patients as well as in 34 victims of violence without PTSD and in a community control group (n = 335). We did not find a statistical significant difference between the BDNF val66met and 5-HTTPRL polymorphism and the traumatic phenotype. However, a statistical association was found between DAT1 3`UTR VNTR nine repeats and PTSD (OR = 1.82; 95% CI, 1.20-2.76). This preliminary result confirms previous reports supporting a susceptibility role for allele 9 and PTSD.

Representational Difference Analysis (RDA) reveals differential expression of conserved as well as novel genes during caste-specific development of the honey bee (Apis mellifera L.) ovary

In highly eusocial insects, such as the honey bee, Apis mellifera, the reproductive bias has become embedded in morphological caste differences. These are most expressively denoted in ovary size, with adult queens having large ovaries consisting of 150-200 ovarioles each, while workers typically have only 1-20 ovarioles per ovary. This morphological differentiation is a result of hormonal signals triggered by the diet change in the third larval instar, which eventually generate caste-specific gene expression patterns. To reveal these we produced differential gene expression libraries by Representational Difference Analysis (RDA) for queen and worker ovaries in a developmental stage when cell death is a prominent feature in the ovarioles of workers, whereas all ovarioles are maintained and extend in length in queens. In the queen library, 48% of the gene set represented homologs of known Drosophila genes, whereas in the worker ovary, the largest set (59%) were ESTs evidencing novel genes, not even computationally predicted in the honey bee genome. Differential expression was confirmed by quantitative RT-PCR for a selected gene set, denoting major differences for two queen and two worker library genes. These included two unpredicted genes located in chromosome 11 (Group11.35 and Group11.31, respectively) possibly representing long non-coding RNAs. Being candidates as modulators of ovary development, their expression and functional analysis should be a focal point for future studies. (C) 2011 Elsevier Ltd. All rights reserved.

Insulin-like peptide genes in honey bee fat body respond differently to manipulation of social behavioral physiology

Nutrient sensitive insulin-like peptides (ILPs) have profound effects on invertebrate metabolism, nutrient storage, fertility and aging. Many insects transcribe ILPs in specialized neurosecretory cells at changing levels correlated with life history. However, the major site of insect metabolism and nutrient storage is not the brain, but rather the fat body, where functions of ILP expression are rarely studied and poorly understood. Fat body is analogous to mammalian liver and adipose tissue, with nutrient stores that often correlate with behavior. We used the honey bee (Apis mellifera), an insect with complex behavior, to test whether ILP genes in fat body respond to experimentally induced changes of behavioral physiology. Honey bee fat body influences endocrine state and behavior by secreting the yolk protein precursor vitellogenin (Vg), which suppresses lipophilic juvenile hormone and social foraging behavior. In a two-factorial experiment, we used RNA interference (RNAi)-mediated vg gene knockdown and amino acid nutrient enrichment of hemolymph (blood) to perturb this regulatory module. We document factor-specific changes in fat body ilp1 and ilp2 mRNA, the bee`s ILP-encoding genes, and confirm that our protocol affects social behavior. We show that ilp1 and ilp2 are regulated independently and differently and diverge in their specific expression-localization between fat body oenocyte and trophocyte cells. Insect ilp functions may be better understood by broadening research to account for expression in fat body and not only brain.

Differential expression of hypoxia pathway genes in honey bee (Apis mellifera L.) caste development

Diphenism in social bees is essentially contingent on nutrient-induced cellular and systemic physiological responses resulting in divergent gene expression patterns. Analyses of juvenile hormone (JH) titers and functional genomics assays of the insulin-insulin-like signaling (IIS) pathway and its associated branch, target-of-rapamycin (TOR), revealed systemic responses underlying honey bee (Apis mellifera) caste development. Nevertheless, little attention has been paid to cellular metabolic responses. Following up earlier investigations showing major caste differences in oxidative metabolism and mitochondrial physiology, we herein identified honey bee homologs of hypoxia signaling factors, HIF alpha/Sima, HIF beta/Tango and PHD/Fatiga and we investigated their transcript levels throughout critical stages of larval development. Amsima, Amtango and Amfatiga showed correlated transcriptional activity, with two peaks of occurring in both queens and workers, the first one shortly after the last larval molt and the second during the cocoon-spinning phase. Transcript levels for the three genes were consistently higher in workers. As there is no evidence for major microenvironmental differences in oxygen levels within the brood nest area, this appears to be an inherent caste character. Quantitative PCR analyses on worker brain, ovary, and leg imaginal discs showed that these tissues differ in transcript levels. Being a highly conserved pathway and linked to IIS/TOR, the hypoxia gene expression pattern seen in honey bee larvae denotes that the hypoxia pathway has undergone a transformation, at least during larval development, from a response to environmental oxygen concentrations to an endogenous regulatory factor in the diphenic development of honey bee larvae. (C) 2010 Elsevier Ltd. All rights reserved.

Gene expression profile analysis of primary glioblastomas and non-neoplastic brain tissue: identification of potential target genes by oligonucleotide microarray and real-time quantitative PCR

The prognosis of glioblastomas is still extremely poor and the discovery of novel molecular therapeutic targets can be important to optimize treatment strategies. Gene expression analyses comparing normal and neoplastic tissues have been used to identify genes associated with tumorigenesis and potential therapeutic targets. We have used this approach to identify differentially expressed genes between primary glioblastomas and non-neoplastic brain tissues. We selected 20 overexpressed genes related to cell cycle, cellular movement and growth, proliferation and cell-to-cell signaling and analyzed their expression levels by real time quantitative PCR in cDNA obtained from microdissected fresh tumor tissue from 20 patients with primary glioblastomas and from 10 samples of non-neoplastic white matter tissue. The gene expression levels were significantly higher in glioblastomas than in non-neoplastic white matter in 18 out of 20 genes analyzed: P < 0.00001 for CDKN2C, CKS2, EEF1A1, EMP3, PDPN, BNIP2, CA12, CD34, CDC42EP4, PPIE, SNAI2, GDF15 and MMP23b; and NFIA (P: 0.0001), GPS1 (P: 0.0003), LAMA1 (P: 0.002), STIM1 (P: 0.006), and TASP1 (P: 0.01). Five of these genes are located in contiguous loci at 1p31-36 and 2 at 17q24-25 and 8 of them encode surface membrane proteins. PDPN and CD34 protein expression were evaluated by immunohistochemistry and they showed concordance with the PCR results. The present results indicate the presence of 18 overexpressed genes in human primary glioblastomas that may play a significant role in the pathogenesis of these tumors and that deserve further functional investigation as attractive candidates for new therapeutic targets.

Abnormal Methylation of Histone Deacetylase Genes: Implications on Etiology and Epigenetic Therapy of Astrocytomas

Background: A growing body of evidence has revealed, the involvement of epigenetic alterations in the etiology of astrocytomas. In the present study, we aimed to evaluate the association of DNA methylation of histone deacetylase genes (HDAC) with the etiology of astrocytoma, and the implications for epigenetic therapy. Materials and Methods: Methylation of the HDAC4, HDAC5 and HDAC6 genes was assessed in 29 tumor samples (astrocytomas grades I, III, and IV) and in the glioblastoma cell lines U87, U251, U343, SF188, and T98G by methylation-specific quantitative PCR (MSED-qPCR). Results: Significantly increased methylation of the HDAC5 gene was observed in astrocytomas when compared to non-neoplastic brain samples (p=0.0007) and to glioblastomas cell lines (p=0.001). A heterogenic methylation pattern was evidenced when compared to the glioblastoma cell lines. Distinct effects on methylation and gene expression were observed after in vitro treatment of the different cell lines with decitabine. Conclusion: Our results suggest that abnormal methylation of HDAC genes is involved in the etiology of astrocytomas and indicate that loci-specific epigenetic interindividualities might be associated to the differential responses to treatment with decitabine.

Inhibition of Expression of HTLV-1 Structural Genes Mediated by Short Hairpin RNA In Vitro

Background: Human T-lymphotropic virus 1 (HTLV-1) is associated with the T-cell malignancy known as adult T-cell leukemia! lymphoma (ATLL) and with a disorder called HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Currently, the treatment of these diseases is based on symptom relief. RNA interference (RNAi) technology has been described as an efficient mechanism for development of new therapeutic methods. Thus, the aim of this study was to evaluate the inhibition of HTLV-1 structural proteins using short hairpin RNAs (shRNAs) expressed by non-viral vectors. Materials and Methods: Reporter plasmids that express enhanced green fluorescent protein-Gag (EGFP-Gag) and EGFP-Env fusion proteins and vectors that express shRNAs corresponding to the HTLV-1 gag and env genes were constructed. shRNA vectors and reporter plasmids were simultaneously transfected into HEK 293 cells. Results: Fluorescence microscopy, flow cytometry and real-time PCR showed that shRNAs were effective in inhibiting the fusion proteins. Conclusion: These shRNAs are effective against the expression of structural genes and may provide an approach to the development of new therapeutic agents.

Genetic Susceptibility Loci in Rheumatoid Arthritis Establish Transcriptional Regulatory Networks with Other Genes

Linkage studies have identified the human leukocyte antigen (HLA)-DRB1 as a putative rheumatoid arthritis (RA) susceptibility locus (SL). Nevertheless, it was estimated that its contribution was partial, suggesting that other non-HLA genes may play a role in RA susceptibility. To test this hypothesis, we conducted microarray transcription profiling of peripheral blood mononuclear cells in 15 RA patients and analyzed the data, using bioinformatics programs (significance analysis of microarrays method and GeneNetwork), which allowed us to determine the differentially expressed genes and to reconstruct transcriptional networks. The patients were grouped according to disease features or treatment with tumor necrosis factor blocker. Transcriptional networks that were reconstructed allowed us to identify the interactions occurring between RA SL and other genes, for example, HLA-DRB1 interacting with FNDC3A (fibronectin type III domain containing 3A). Given that fibronectin fragments can stimulate mediators of matrix and cartilage destruction in RA, this interaction is of special interest and may contribute to a clearer understanding of the functional role of HLA-DRB1 in RA pathogenesis.