664 research outputs found
Physical interaction between MYCN oncogene and polycomb repressive complex 2 (PRC2) in neuroblastoma: Functional and therapeutic implications
This article is made available through the Brunel Open Access Publishing Fund. © 2013 by The American Society for Biochemistry and Molecular Biology, Inc.CLU (clusterin) is a tumor suppressor gene that we have previously shown to be negatively modulated by the MYCN proto-oncogene, but the mechanism of repression was unclear. Here, we show that MYCN inhibits the expression of CLU by direct interaction with the non-canonical E box sequence CACGCG in the 5′-flanking region. Binding of MYCN to the CLU gene induces bivalent epigenetic marks and recruitment of repressive proteins such as histone deacetylases and Polycomb members. MYCN physically binds in vitro and in vivo to EZH2, a component of the Polycomb repressive complex 2, required to repress CLU. Notably, EZH2 interacts with the Myc box domain 3, a segment of MYC known to be essential for its transforming effects. The expression of CLU can be restored in MYCN-amplified cells by epigenetic drugs with therapeutic results. Importantly, the anticancer effects of the drugs are ablated if CLU expression is blunted by RNA interference. Our study implies that MYC tumorigenesis can be effectively antagonized by epigenetic drugs that interfere with the recruitment of chromatin modifiers at repressive E boxes of tumor suppressor genes such as CLU.SPARKS, The Neuroblastoma Society,
a Wellcome Trust grant (to A. S.), and the Italian Association for Cancer
Research
Heterologous RNA silencing suppressors from both plant- and animal-infecting viruses support Plum pox virus infection
[EN] HCPro, the RNA silencing suppressor (RSS) of viruses belonging to the Potyvirus genus in the Potyviridae family, is a multifunctional protein presumably involved in all essential steps of the viral infection cycle. Recent studies have shown that Plum pox potyvirus (PPV) HCPro can be successfully replaced by Cucumber vein yellowing ipomovirus P1b, a sequence unrelated RSS from a virus of the same family. In order to gain insight into the requirement of a particular RSS to establish a successful potyviral infection, we tested the ability of different heterologous RSSs from both plant- and animal-infecting viruses to substitute HCPro. Making use of engineered PPV chimeras, we show that PPV HCPro can be functionally replaced by some, but not all, unrelated
RSSs, including the NS1 protein of the mammalian-infecting Influenza A virus. Interestingly, the capacity of a particular RSS to replace HCPro does not strictly correlate with its RNA silencing suppression strength. Altogether, our results suggest that not all suppression strategies are equally suitable for an efficient escape of PPV from the RNA silencing machinery. The approach followed here based on using PPV chimeras in which an under-consideration RSS substitutes for HCPro could further help to study the function of diverse RSSs in a ¿highly-sensitive¿ RNA silencing context, such as that taking place in plant cells during the process of a viral infection.We are especially grateful to those people who sent us plasmids containing the DNA sequence of different viral proteins. We thank Veronique Ziegler-Graff for providing BWYV P0, Ana Giner and Juan Jose Lopez-Moya for providing SPMMV P1, Joel Milner for providing CaMV P6, Maria Rosa Lopez-Huertas and Jose Alcami for providing HIV Tat, Jan Kreuze for providing SPCSV RNase3, and M. Taliansky for providing GRV ORF3. We thank Herman Scholthof and Ariel Rodriguez for providing anti-P19 and anti-NS1 serum, respectively. We are also grateful to David Baulcombe for providing the GFP expression vector and TBSV P19-containing plasmid, and Mark Curtis for providing the pMDC32 destination vector. This work was supported by grants from Spanish MICINN (BIO2010-18541) and the European Union (KBBE-204429). M. C. was the recipient of an 13P fellowship from CSIC-Fondo Social Europeo.Maliogka, VI.; Calvo, M.; Carbonell, A.; Garcia, JA.; Valli, A. (2012). Heterologous RNA silencing suppressors from both plant- and animal-infecting viruses support Plum pox virus infection. Journal of General Virology. 93(7):1601-1611. https://doi.org/10.1099/vir.0.042168-0S16011611937Ala-Poikela, M., Goytia, E., Haikonen, T., Rajamäki, M.-L., & Valkonen, J. P. T. (2011). Helper Component Proteinase of the Genus Potyvirus Is an Interaction Partner of Translation Initiation Factors eIF(iso)4E and eIF4E and Contains a 4E Binding Motif. Journal of Virology, 85(13), 6784-6794. doi:10.1128/jvi.00485-11Ambros, V., & Chen, X. (2007). The regulation of genes and genomes by small RNAs. Development, 134(9), 1635-1641. doi:10.1242/dev.002006Anandalakshmi, R., Pruss, G. J., Ge, X., Marathe, R., Mallory, A. C., Smith, T. H., & Vance, V. B. (1998). A viral suppressor of gene silencing in plants. Proceedings of the National Academy of Sciences, 95(22), 13079-13084. doi:10.1073/pnas.95.22.13079Anandalakshmi, R., Marathe, R., Ge, X., Herr, J. M., Mau, C., Mallory, A., … Vance, V. B. (2000). A Calmodulin-Related Protein That Suppresses Posttranscriptional Gene Silencing in Plants. Science, 290(5489), 142-144. doi:10.1126/science.290.5489.142Ballut, L., Drucker, M., Pugnière, M., Cambon, F., Blanc, S., Roquet, F., … Badaoui, S. (2005). HcPro, a multifunctional protein encoded by a plant RNA virus, targets the 20S proteasome and affects its enzymic activities. Journal of General Virology, 86(9), 2595-2603. doi:10.1099/vir.0.81107-0Baulcombe, D. (2005). RNA silencing. Trends in Biochemical Sciences, 30(6), 290-293. doi:10.1016/j.tibs.2005.04.012Bennasser, Y., Le, S.-Y., Benkirane, M., & Jeang, K.-T. (2005). Evidence that HIV-1 Encodes an siRNA and a Suppressor of RNA Silencing. Immunity, 22(5), 607-619. doi:10.1016/j.immuni.2005.03.010Blanc, S., López-Moya, J.-J., Wang, R., García-Lampasona, S., Thornbury, D. W., & Pirone, T. P. (1997). A Specific Interaction between Coat Protein and Helper Component Correlates with Aphid Transmission of a Potyvirus. Virology, 231(1), 141-147. doi:10.1006/viro.1997.8521Brigneti, G. (1998). Viral pathogenicity determinants are suppressors of transgene silencing in Nicotiana benthamiana. The EMBO Journal, 17(22), 6739-6746. doi:10.1093/emboj/17.22.6739Bucher, E., Hemmes, H., de Haan, P., Goldbach, R., & Prins, M. (2004). The influenza A virus NS1 protein binds small interfering RNAs and suppresses RNA silencing in plants. Journal of General Virology, 85(4), 983-991. doi:10.1099/vir.0.19734-0Burgyán, J., & Havelda, Z. (2011). Viral suppressors of RNA silencing. Trends in Plant Science, 16(5), 265-272. doi:10.1016/j.tplants.2011.02.010Carbonell, A., Dujovny, G., García, J. A., & Valli, A. (2012). The Cucumber vein yellowing virus Silencing Suppressor P1b Can Functionally Replace HCPro in Plum pox virus Infection in a Host-Specific Manner. Molecular Plant-Microbe Interactions®, 25(2), 151-164. doi:10.1094/mpmi-08-11-0216Carrington, J. C., Cary, S. M., Parks, T. D., & Dougherty, W. G. (1989). A second proteinase encoded by a plant potyvirus genome. The EMBO Journal, 8(2), 365-370. doi:10.1002/j.1460-2075.1989.tb03386.xCheng, Y.-Q., Liu, Z.-M., Xu, J., Zhou, T., Wang, M., Chen, Y.-T., … Fan, Z.-F. (2008). HC-Pro protein of sugar cane mosaic virus interacts specifically with maize ferredoxin-5 in vitro and in planta. Journal of General Virology, 89(8), 2046-2054. doi:10.1099/vir.0.2008/001271-0Choi, I.-R., Stenger, D. C., & French, R. (2000). Multiple Interactions among Proteins Encoded by the Mite-Transmitted Wheat Streak Mosaic Tritimovirus. Virology, 267(2), 185-198. doi:10.1006/viro.1999.0117Cuellar, W. J., Kreuze, J. F., Rajamaki, M.-L., Cruzado, K. R., Untiveros, M., & Valkonen, J. P. T. (2009). Elimination of antiviral defense by viral RNase III. Proceedings of the National Academy of Sciences, 106(25), 10354-10358. doi:10.1073/pnas.0806042106Delgadillo, M. O., Sáenz, P., Salvador, B., García, J. A., & Simón-Mateo, C. (2004). Human influenza virus NS1 protein enhances viral pathogenicity and acts as an RNA silencing suppressor in plants. Journal of General Virology, 85(4), 993-999. doi:10.1099/vir.0.19735-0DIELEN, A.-S., SASSAKI, F. T., WALTER, J., MICHON, T., MÉNARD, G., PAGNY, G., … GERMAN-RETANA, S. (2010). The 20S proteasome α5 subunit of Arabidopsis thaliana carries an RNase activity and interacts in planta with the Lettuce mosaic potyvirus HcPro protein. Molecular Plant Pathology, 12(2), 137-150. doi:10.1111/j.1364-3703.2010.00654.xDing, S.-W. (2010). RNA-based antiviral immunity. Nature Reviews Immunology, 10(9), 632-644. doi:10.1038/nri2824Ding, S. W., Li, W. X., & Symons, R. H. (1995). A novel naturally occurring hybrid gene encoded by a plant RNA virus facilitates long distance virus movement. The EMBO Journal, 14(23), 5762-5772. doi:10.1002/j.1460-2075.1995.tb00265.xDunoyer, P., & Voinnet, O. (2005). The complex interplay between plant viruses and host RNA-silencing pathways. Current Opinion in Plant Biology, 8(4), 415-423. doi:10.1016/j.pbi.2005.05.012Endres, M. W., Gregory, B. D., Gao, Z., Foreman, A. W., Mlotshwa, S., Ge, X., … Vance, V. (2010). Two Plant Viral Suppressors of Silencing Require the Ethylene-Inducible Host Transcription Factor RAV2 to Block RNA Silencing. PLoS Pathogens, 6(1), e1000729. doi:10.1371/journal.ppat.1000729Garcia-Ruiz, H., Takeda, A., Chapman, E. J., Sullivan, C. M., Fahlgren, N., Brempelis, K. J., & Carrington, J. C. (2010). Arabidopsis RNA-Dependent RNA Polymerases and Dicer-Like Proteins in Antiviral Defense and Small Interfering RNA Biogenesis during Turnip Mosaic Virus Infection
. The Plant Cell, 22(2), 481-496. doi:10.1105/tpc.109.073056Gazzani, S., Lawrenson, T., Woodward, C., Headon, D., & Sablowski, R. (2004). A Link Between mRNA Turnover and RNA Interference in
Arabidopsis. Science, 306(5698), 1046-1048. doi:10.1126/science.1101092Giner, A., Lakatos, L., García-Chapa, M., López-Moya, J. J., & Burgyán, J. (2010). Viral Protein Inhibits RISC Activity by Argonaute Binding through Conserved WG/GW Motifs. PLoS Pathogens, 6(7), e1000996. doi:10.1371/journal.ppat.1000996Guo, D., Rajamäki, M.-L., Saarma, M., & Valkonen, J. P. T. (2001). Towards a protein interaction map of potyviruses: protein interaction matrixes of two potyviruses based on the yeast two-hybrid system. Journal of General Virology, 82(4), 935-939. doi:10.1099/0022-1317-82-4-935Guo, D., Spetz, C., Saarma, M., & Valkonen, J. P. T. (2003). Two Potato Proteins, Including a Novel RING Finger Protein (HIP1), Interact with the Potyviral Multifunctional Protein HCpro. Molecular Plant-Microbe Interactions®, 16(5), 405-410. doi:10.1094/mpmi.2003.16.5.405Haas, G., Azevedo, J., Moissiard, G., Geldreich, A., Himber, C., Bureau, M., … Voinnet, O. (2008). Nuclear import of CaMV P6 is required for infection and suppression of the RNA silencing factor DRB4. The EMBO Journal, 27(15), 2102-2112. doi:10.1038/emboj.2008.129Haasnoot, J., de Vries, W., Geutjes, E.-J., Prins, M., de Haan, P., & Berkhout, B. (2007). The Ebola Virus VP35 Protein Is a Suppressor of RNA Silencing. PLoS Pathogens, 3(6), e86. doi:10.1371/journal.ppat.0030086Havelda, Z., Hornyik, C., Crescenzi, A., & Burgyán, J. (2003). In Situ Characterization of
Cymbidium Ringspot Tombusvirus
Infection-Induced Posttranscriptional Gene Silencing in
Nicotiana benthamiana. Journal of Virology, 77(10), 6082-6086. doi:10.1128/jvi.77.10.6082-6086.2003Janssen, D., Martín, G., Velasco, L., Gómez, P., Segundo, E., Ruiz, L., & Cuadrado, I. M. (2005). Absence of a coding region for the helper component-proteinase in the genome of cucumber vein yellowing virus, a whitefly-transmitted member of the Potyviridae. Archives of Virology, 150(7), 1439-1447. doi:10.1007/s00705-005-0515-zJin, Y., Ma, D., Dong, J., Jin, J., Li, D., Deng, C., & Wang, T. (2007). HC-Pro Protein of
Potato Virus Y
Can Interact with Three
Arabidopsis
20S Proteasome Subunits In Planta. Journal of Virology, 81(23), 12881-12888. doi:10.1128/jvi.00913-07Jin, Y., Ma, D., Dong, J., Li, D., Deng, C., Jin, J., & Wang, T. (2007). The HC-Pro Protein of Potato Virus Y Interacts with NtMinD of Tobacco. Molecular Plant-Microbe Interactions®, 20(12), 1505-1511. doi:10.1094/mpmi-20-12-1505Kasschau, K. D., & Carrington, J. C. (1995). Requirement for HC-Pro Processing during Genome Amplification of Tobacco Etch Potyvirus. Virology, 209(1), 268-273. doi:10.1006/viro.1995.1254Kasschau, K. D., & Carrington, J. C. (1998). A Counterdefensive Strategy of Plant Viruses. Cell, 95(4), 461-470. doi:10.1016/s0092-8674(00)81614-1Kasschau, K. D., & Carrington, J. C. (2001). Long-Distance Movement and Replication Maintenance Functions Correlate with Silencing Suppression Activity of Potyviral HC-Pro. Virology, 285(1), 71-81. doi:10.1006/viro.2001.0901Kasschau, K. D., Xie, Z., Allen, E., Llave, C., Chapman, E. J., Krizan, K. A., & Carrington, J. C. (2003). P1/HC-Pro, a Viral Suppressor of RNA Silencing, Interferes with Arabidopsis Development and miRNA Function. Developmental Cell, 4(2), 205-217. doi:10.1016/s1534-5807(03)00025-xLakatos, L., Csorba, T., Pantaleo, V., Chapman, E. J., Carrington, J. C., Liu, Y.-P., … Burgyán, J. (2006). Small RNA binding is a common strategy to suppress RNA silencing by several viral suppressors. The EMBO Journal, 25(12), 2768-2780. doi:10.1038/sj.emboj.7601164Lecellier, C.-H., Dunoyer, P., Arar, K., Lehmann-Che, J., Eyquem, S., Himber, C., … Voinnet, O. (2005). A Cellular MicroRNA Mediates Antiviral Defense in Human Cells. Science, 308(5721), 557-560. doi:10.1126/science.1108784Li, W.-X., Li, H., Lu, R., Li, F., Dus, M., Atkinson, P., … Ding, S.-W. (2004). Interferon antagonist proteins of influenza and vaccinia viruses are suppressors of RNA silencing. Proceedings of the National Academy of Sciences, 101(5), 1350-1355. doi:10.1073/pnas.0308308100Love, A. J., Laird, J., Holt, J., Hamilton, A. J., Sadanandom, A., & Milner, J. J. (2007). Cauliflower mosaic virus protein P6 is a suppressor of RNA silencing. Journal of General Virology, 88(12), 3439-3444. doi:10.1099/vir.0.83090-0Maia, I. G., Haenni, A.-L., & Bernardi, F. (1996). Potyviral HC-Pro: a multifunctional protein. Journal of General Virology, 77(7), 1335-1341. doi:10.1099/0022-1317-77-7-1335Merits, A., Guo, D., Järvekülg, L., & Saarma, M. (1999). Biochemical and Genetic Evidence for Interactions between Potato A Potyvirus-Encoded Proteins P1 and P3 and Proteins of the Putative Replication Complex. Virology, 263(1), 15-22. doi:10.1006/viro.1999.9926Qian, S., Zhong, X., Yu, L., Ding, B., de Haan, P., & Boris-Lawrie, K. (2009). HIV-1 Tat RNA silencing suppressor activity is conserved across kingdoms and counteracts translational repression of HIV-1. Proceedings of the National Academy of Sciences, 106(2), 605-610. doi:10.1073/pnas.0806822106Qiu, W., Park, J.-W., & Scholthof, H. B. (2002). Tombusvirus P19-Mediated Suppression of Virus-Induced Gene Silencing Is Controlled by Genetic and Dosage Features That Influence Pathogenicity. Molecular Plant-Microbe Interactions®, 15(3), 269-280. doi:10.1094/mpmi.2002.15.3.269Roth, B. (2004). Plant viral suppressors of RNA silencing. Virus Research, 102(1), 97-108. doi:10.1016/j.virusres.2004.01.020Roudet-Tavert, G., German-Retana, S., Delaunay, T., Delécolle, B., Candresse, T., & Le Gall, O. (2002). Interaction between potyvirus helper component-proteinase and capsid protein in infected plants. Journal of General Virology, 83(7), 1765-1770. doi:10.1099/0022-1317-83-7-1765Roudet-Tavert, G., Michon, T., Walter, J., Delaunay, T., Redondo, E., & Le Gall, O. (2007). Central domain of a potyvirus VPg is involved in the interaction with the host translation initiation factor eIF4E and the viral protein HcPro. Journal of General Virology, 88(3), 1029-1033. doi:10.1099/vir.0.82501-0Sáenz, P., Salvador, B., Simón-Mateo, C., Kasschau, K. D., Carrington, J. C., & García, J. A. (2002). Host-Specific Involvement of the HC Protein in the Long-Distance Movement of Potyviruses. Journal of Virology, 76(4), 1922-1931. doi:10.1128/jvi.76.4.1922-1931.2002Shimura, H., & Pantaleo, V. (2011). Viral induction and suppression of RNA silencing in plants. Biochimica et Biophysica Acta (BBA) - Gene Regulatory Mechanisms, 1809(11-12), 601-612. doi:10.1016/j.bbagrm.2011.04.005Silhavy, D. (2002). A viral protein suppresses RNA silencing and binds silencing-generated, 21- to 25-nucleotide double-stranded RNAs. The EMBO Journal, 21(12), 3070-3080. doi:10.1093/emboj/cdf312Stenger, D. C., French, R., & Gildow, F. E. (2005). Complete Deletion of
Wheat Streak Mosaic Virus
HC-Pro: a Null Mutant Is Viable for Systemic Infection. Journal of Virology, 79(18), 12077-12080. doi:10.1128/jvi.79.18.12077-12080.2005Syller, J. (2005). The roles and mechanisms of helper component proteins encoded by potyviruses and caulimoviruses. Physiological and Molecular Plant Pathology, 67(3-5), 119-130. doi:10.1016/j.pmpp.2005.12.005Valli, A., Martín-Hernández, A. M., López-Moya, J. J., & García, J. A. (2006). RNA Silencing Suppression by a Second Copy of the P1 Serine Protease ofCucumber Vein Yellowing Ipomovirus, a Member of the FamilyPotyviridaeThat Lacks the Cysteine Protease HCPro. Journal of Virology, 80(20), 10055-10063. doi:10.1128/jvi.00985-06Valli, A., L��pez-Moya, J. J., & Garc��a, J. A. (2009). RNA Silencing and its Suppressors in the Plant-virus Interplay. Encyclopedia of Life Sciences. doi:10.1002/9780470015902.a0021261Valli, A., Oliveros, J. C., Molnar, A., Baulcombe, D., & Garcia, J. A. (2011). The specific binding to 21-nt double-stranded RNAs is crucial for the anti-silencing activity of Cucumber vein yellowing virus P1b and perturbs endogenous small RNA populations. RNA, 17(6), 1148-1158. doi:10.1261/rna.2510611Vargason, J. M., Szittya, G., Burgyán, J., & Hall, T. M. T. (2003). Size Selective Recognition of siRNA by an RNA Silencing Suppressor. Cell, 115(7), 799-811. doi:10.1016/s0092-8674(03)00984-xVoinnet, O., Pinto, Y. M., & Baulcombe, D. C. (1999). Suppression of gene silencing: A general strategy used by diverse DNA and RNA viruses of plants. Proceedings of the National Academy of Sciences, 96(24), 14147-14152. doi:10.1073/pnas.96.24.14147Yambao, M. L. M., Masuta, C., Nakahara, K., & Uyeda, I. (2003). The central and C-terminal domains of VPg of Clover yellow vein virus are important for VPg–HCPro and VPg–VPg interactions. Journal of General Virology, 84(10), 2861-2869. doi:10.1099/vir.0.19312-0Young, B. A., Stenger, D. C., Qu, F., Morris, T. J., Tatineni, S., & French, R. (2012). Tritimovirus P1 functions as a suppressor of RNA silencing and an enhancer of disease symptoms. Virus Research, 163(2), 672-677. doi:10.1016/j.virusres.2011.12.019Zilian, E., & Maiss, E. (2011). Detection of plum pox potyviral protein–protein interactions in planta using an optimized mRFP-based bimolecular fluorescence complementation system. Journal of General Virology, 92(12), 2711-2723. doi:10.1099/vir.0.033811-
Boson-exchange parquet solver for dual fermions
We present and implement a parquet approximation within the dual-fermion formalism based on a partial bosonization of the dual vertex function which substantially reduces the computational cost of the calculation. The method relies on splitting the vertex exactly into single-boson exchange contributions and a residual four-fermion vertex, which physically embody, respectively, long- and short-range spatial correlations. After recasting the parquet equations in terms of the residual vertex, these are solved using the truncated-unity method of Eckhardt et al. [Phys. Rev. B 101, 155104 (2020)2469-995010.1103/PhysRevB.101.155104], which allows for a rapid convergence with the number of form factors in different regimes. While our numerical treatment of the parquet equations can be restricted to only a few Matsubara frequencies, reminiscent of Astretsov et al. [Phys. Rev. B 101, 075109 (2020)2469-995010.1103/PhysRevB.101.075109], the one- and two-particle spectral information is fully retained. In applications to the two-dimensional Hubbard model the method agrees quantitatively with a stochastic summation of diagrams over a wide range of parameters
Canopy uptake dominates nighttime carbonyl sulfide fluxes in a boreal forest
Nighttime vegetative uptake of carbonyl sulfide (COS) can exist due to the incomplete closure of stomata and the light independence of the enzyme carbonic anhydrase, which complicates the use of COS as a tracer for gross primary productivity (GPP). In this study we derived nighttime COS fluxes in a boreal forest (the SMEAR II station in Hyytiälä, Finland; 61°51′ N, 24°17′ E; 181 m a.s.l.) from June to November 2015 using two different methods: eddy-covariance (EC) measurements (FCOS-EC) and the radon-tracer method (FCOS-Rn). The total nighttime COS fluxes averaged over the whole measurement period were −6.8 ± 2.2 and −7.9 ± 3.8 pmol m−2 s−1 for FCOS-Rn and FCOS-EC, respectively, which is 33–38 % of the average daytime fluxes and 21 % of the total daily COS uptake. The correlation of 222Rn (of which the source is the soil) with COS (average R2 = 0.58) was lower than with CO2 (0.70), suggesting that the main sink of COS is not located at the ground. These observations are supported by soil chamber measurements that show that soil contributes to only 34–40 % of the total nighttime COS uptake. We found a decrease in COS uptake with decreasing nighttime stomatal conductance and increasing vapor-pressure deficit and air temperature, driven by stomatal closure in response to a warm and dry period in August. We also discuss the effect that canopy layer mixing can have on the radon-tracer method and the sensitivity of (FCOS-EC) to atmospheric turbulence. Our results suggest that the nighttime uptake of COS is mainly driven by the tree foliage and is significant in a boreal forest, such that it needs to be taken into account when using COS as a tracer for GPP
Counteracting the Common Shwachman–Diamond Syndrome-Causing SBDS c.258+2T>C Mutation by RNA Therapeutics and Base/Prime Editing
Shwachman-Diamond syndrome (SDS) represents one of the most common inherited bone marrow failure syndromes and is mainly caused by SBDS gene mutations. Only supportive treatments are available, with hematopoietic cell transplantation required when marrow failure occurs. Among all causative mutations, the SBDS c.258+2T>C variant at the 5 ' splice site (ss) of exon 2 is one of the most frequent. Here, we investigated the molecular mechanisms underlying aberrant SBDS splicing and showed that SBDS exon 2 is dense in splicing regulatory elements and cryptic splice sites, complicating proper 5 ' ss selection. Studies ex vivo and in vitro demonstrated that the mutation alters splicing, but it is also compatible with tiny amounts of correct transcripts, which would explain the survival of SDS patients. Moreover, for the first time for SDS, we explored a panel of correction approaches at the RNA and DNA levels and provided experimental evidence that the mutation effect can be partially counteracted by engineered U1snRNA, trans-splicing, and base/prime editors, ultimately leading to correctly spliced transcripts (from barely detectable to 2.5-5.5%). Among them, we propose DNA editors that, by stably reverting the mutation and potentially conferring positive selection to bone-marrow cells, could lead to the development of an innovative SDS therapy
Incidence and clinicopathologic features of gastrointestinal stromal tumors. A population-based study.
BACKGROUND: Although the diagnostic criteria and pathogenesis of gastrointestinal stromal tumors (GIST) have recently been elucidated, knowledge of the epidemiology of this malignancy is still limited. This study examined the incidence of GIST in the province of Modena, including pathologic features and clinical outcome. METHODS: Gastrointestinal mesenchymal tumors identified by the Modena Cancer Registry between 1991 and 2004 were analyzed with an immunohistochemical panel that included staining for CD-117 and PDGFRalpha. Size, mitotic rate, and other pathologic parameters were recorded. Each tumor was categorized into National Institutes of Health risk categories (very low, low, intermediate, and high risk). RESULTS: One hundred twenty-four cases were classified as GIST. The age-adjusted incidence rate was 6.6 per million. Seventy-five percent of patients were symptomatic; 34% had a previous or concomitant history of cancer. High-risk features were present in 47% of cases. Seventy-eight percent were submitted to radical surgery. After complete resection, the 5-year disease-free survival rates were 94%, 92%, 100%, and 40% for patients at very low, low, intermediate, and high risk, respectively. In multivariate analysis, high risk was the main predictor of recurrence. CONCLUSION: This population-based study shows that the incidence of GIST in Northern Italy is comparable to that reported in other European countries. Survival was favorable in lower risk categories and in most of the resected cases. In our study, resected patients at very low, low, and intermediate risk had a similar outcome. Our data support the need to consider high-risk patients after complete surgical resection for treatment with the best available approach
Elemental characterization of PM10, PM2.5 and PM1 in the town of Genoa (Italy)
The particulate matter (PM) concentration and composition, the PM10, PM2.5, PM1 fractions, were studied in the
urban area of Genoa, a coastal town in the northwest of Italy. Two instruments, the continuous monitor TEOM and
the sequential sampler PARTISOL, were operated almost continuously on the same site from July 2001 to September
2004. Samples collected by PARTISOL were weighted to obtain PM concentration and then analysed by PIXE (particle
induced X-ray emission) and by ED-XRF (energy dispersion X-ray fluorescence), obtaining concentrations for elements
from Na to Pb. Some of the filters used in the TEOM microbalance were analysed by ED-XRF to calculate Pb concentration values averaged over 7\u201330 d periods
Sacubitril/Valsartan in heart failure with reduced ejection fraction: clinical and echocardiographic insights from a real world population
Abstract
Background
Following the PARADIGM trial, some studies have identified cardiac remodeling as major background for hard end point benefits of Sacubitril/Valsartan (S/V), but few adopted a well described definition in the literature.
Purpose
We aimed at a comprehensive evaluation of the effects of S/V on echo-derived measures of cardiac remodeling along with clinical and laboratory data over a medium-term follow-up pointing to a real-world HFrEF population.
Methods
This is a prospective observational study of HFrEF patients on optimal medical therapy (OMT) initiated with S/V at Heart Failure Clinic of our institute (January 2017-January 2020). In 62 HFrEF, echocardiographic, laboratory and clinical data were collected at baseline and over 10 (Q1-Q3 8–13) months after S/V initiation. Mean age was 68±12 years, 79% men. Left ventricular reverse remodeling (LVRR) was defined as: 1) an absolute increase in LVEF ≥10 points or a LVEF ≥50% at follow-up and 2) a relative decrease in indexed left ventricular end-diastolic diameter of at least 10% or an indexed left ventricular end-diastolic diameter ≤33 mm/m2.
Results
Compared to baseline, S/V promoted a significant improvement of LV ejection fraction (LVEF, from 30% to 37%; p<0,0001) with an absolute median increase in LVEF of 8 points. Parallel significant reductions in left ventricular and atrial volumes, lower mitral regurgitation degree and a better diastolic dysfunction along with clinical improvement (NYHA class and NT-proBNP values) were observed at follow up. sPAP (systolic Pulmonary Arterial Pressure) was significantly decreased at follow-up evaluation (37 mmHg vs 31 mmHg p=0,005) (Table 1). Overall, LVRR as defined above was observed in 30% of patients. Younger age (64 vs 74 years, p=0,007), a shorter duration of the disease (7 vs 23 months, p=0,009), and non ischaemic etiology (79% vs 33% p=0,003), along with a smaller baseline LAESVi (Left Atrial End Systolic Volume, 41 vs 48 ml/m2 p=0,012) were more common in patients with LVRR. sPAP and Right Ventricular (RV) function estimated by tricuspid annular plane systolic excursion (TAPSE) were significantly better in LVRR patients along with TAPSE/sPAP ratio (Table 2).
Conclusions
Our data point to a remarkable medium-term reverse remodeling effect by S/V in HFrEF. Findings reinforce the concept that the main benefits of S/V on hard end-points are mediated by its cardiac-related effects. Both a left and right reverse remodeling occur in HFrEF patients who start S/V in the most adaptable phase of the disease supporting an early administration.
Funding Acknowledgement
Type of funding sources: None
Patterns of practice of regional nodal irradiation in breast cancer: results of the European Organization for Research and Treatment of Cancer (EORTC) NOdal Radiotherapy (NORA) survey†
Predicting breast cancer outcome based on SLN node status without ALND is currently an area of uncertainty in SLN+ patients. These uncertainties influence the decision-making of adjuvant nodal irradiation. The NORA Survey was designed to examine the patterns of RNI practice in Europe to provide a basis for designing future trials in areas of equipoise in clinical decision-making concerning RN
Case Report: Heterozygous Germline Variant in EIF6 Additional to Biallelic SBDS Pathogenic Variants in a Patient With Ribosomopathy Shwachman–Diamond Syndrome
Background: Shwachman-Diamond syndrome (SDS) is a rare autosomal recessive ribosomopathy mainly characterized by exocrine pancreatic insufficiency, skeletal alterations, neutropenia, and a relevant risk of hematological transformation. At least 90% of SDS patients have pathogenic variants in SBDS, the first gene associated with the disease with very low allelic heterogeneity; three variants, derived from events of genetic conversion between SBDS and its pseudogene, SBDSP1, provided the alleles observed in about 62% of SDS patients.Methods: We performed a reanalysis of the available WES files of a group of SDS patients with biallelic SBDS pathogenic variants, studying the results by next bioinformatic and protein structural analysis. Parallelly, careful clinical attention was given to the patient focused in this study.Results: We found and confirmed in one SDS patient a germline heterozygous missense variant (c.100T>C; p.Phe34Leu) in the EIF6 gene. This variant, inherited from his mother, has a very low frequency, and it is predicted as pathogenic, according to several in silico prediction tools. The protein structural analysis also envisages the variant could reduce the binding to the nascent 60S ribosomal.Conclusion: This study focused on the hypothesis that the EIF6 germline variant mimics the effect of somatic deletions of chromosome 20, always including the locus of this gene, and similarly may rescue the ribosomal stress and ribosomal dysfunction due to SBDS mutations. It is likely that this rescue may contribute to the stable and not severe hematological status of the proband, but a definite answer on the role of this EIF6 variant can be obtained only by adding a functional layer of evidence. In the future, these results are likely to be useful for selected cases in personalized medicine and therapy
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