Variably protease-sensitive prionopathy presenting within ALS/FTD spectrum

We report clinico‐pathological features of a 65‐year‐old woman and a 56‐year‐old man with a 5‐year clinical history who had clinical and neuropathological characteristics of upper and lower motor neuron disease consistent with amyotrophic lateral sclerosis, and a frontotemporal atrophy pattern in case 2 without TDP‐43 pathology. Instead, spongiform change and pathological prion protein deposits were observed in several brain regions. No prion protein gene mutations were found. Western blot analysis showed a five‐band profile compatible with variably protease‐sensitive prionopathy. We conclude that this disease can display prolonged disease duration and clinico‐pathological features within the ALS/FTLD spectrum.This work was funded by Department of Public Health Generalitat de Catalunya grant ; Spanish “Ministerio de Economía y Competitividad, Subprograma Técnicos de Apoyo 2014” grant ; Spanish Fondo de Investigaciones Sanitarias grant FIS PI16‐01673‐FEDER; Spanish Ministry of Health ‐ Instituto Carlos III grant Miguel Servet ‐ CP16/00041; Fundació La Marató de TV3 grant 20141610

Variably protease-sensitive prionopathy presenting within ALS/FTD spectrum

We report clinico-pathological features of a 65-year-old woman and a 56-yearold man with a 5-year clinical history who had clinical and neuropathological characteristics of upper and lower motor neuron disease consistent with amyotrophic lateral sclerosis, and a frontotemporal atrophy pattern in case 2 without TDP-43 pathology. Instead, spongiform change and pathological prion protein deposits were observed in several brain regions. No prion protein gene mutations were found. Western blot analysis showed a five-band profile compatible with variably protease-sensitive prionopathy. We conclude that this disease can display prolonged disease duration and clinico-pathological features within the ALS/FTLD spectrum

Titina y utrofina: análisis ultraestructural de distorsión arquitectural sarcomérica y sobreexpresión proteica en biopsias musculares, y correlación diagnóstica

En conclusión, evidenciamos la importante contribución que aportan la EM en el conjunto del estudio de las titinopatías y el estudio de la expresión de utrofina mediante IHC en el estudio de las NMD. La EM pone de manifiesto patrones de lesión y alteraciones sarcoméricas particulares que permitirían ayudar a considerar una probable patogenicidad de las mutaciones en TTN, tras la orientación inicial de la biopsia con técnicas convencionales y la integración con los datos clínicos. La identificación de un patrón DUE permite orientar el diagnóstico, así como valorar la capacidad regenerativa persistente en el tejido. Además, nuestros resultados abren la puerta a nuevos planteamientos: 1) mejorar el entendimiento del mecanismo subyacente a la distorsión sarcomérica en miopatías relacionadas con TTN, 2) identificar nuevos roles de la utrofina, estudiar su mecanismo de expresión y valorar su potencial aplicación en terapia como elemento protector para retrasar el daño de la fibra muscular en ciertas NMD.In conclusion, we show the important contribution of EM in the study of titinopathies and the examination of utrophin expression by IHC in the study of NMDs. EM reveals patterns of injury and particular sarcomeric alterations that may help to consider a probable pathogenicity of mutations in TTN, once the biopsy is oriented with conventional techniques and clinical data are integrated. The expression of utrophin and the identification of a DUE pattern allow to guide the diagnosis, as well as to assess the persistent regenerative capacity in the tissue. In addition, our results open the door to new approaches: 1) to improve the understanding of the mechanism underlying sarcomeric distortion in TTN-related myopathies, 2) to identify new roles for utrophin, study the mechanism of expression and assess its potential application in therapy as a protective element to delay the muscle fibre damage in certain NMDs.Tesis Univ. Granada

NOVEL intronic CAPN3 Roma mutation alters splicing causing RNA mediated decay

CAPN3 mutations cause a limb girdle muscular dystrophy. Functional characterization of novel mutations facilitates diagnosis of future cases. We have identified a novel (c.1992 + 2T>G) CAPN3 mutation that disrupts the donor splice site of intron 17 splicing out exon 17, with mRNA levels severely reduced or undetectable. The mutation induces a strong change in the 3D structure of the mRNA which supports no-go mRNA decay as the probable mechanism for RNA degradation. The mutation was identified in two unrelated Roma individuals showing a common ancestral origin and founder effect. This is the first Roma CAPN3 mutation to be reported.This project has been founded by ISCIII and FEDER “a way to achieve Europe”; Grant number PI16/00612(MC‐S) and PI16/01843 (CP). MC‐S was supported by ISCIII (JR15/00042) and Junta de Andalucia‐Consejeria de Salud (B‐0005‐2017)

Influencia de FBWX7 en la adquisición de resistencia a paclitaxel en cáncer de mama

Póster presentado en el XXXVII Congreso de la Sociedad Española de Bioquímica y Biología Molecular (SEBBM), celbrado en Granada del 9 al 12 de septiembre de 2014.Paclitaxel es un fármaco antimitótico que pertenece al grupo de los taxanos que se emplea en el tratamiento del cáncer metastásico de mama, aunque su utilidad es limitada debido a la aparición de resistencia a esta sustancia. La relación entre la parada de mitosis inducida por paclitaxel y la posterior supervivencia (o muerte) de la célula no se conoce completamente, aunque diversos estudios indican que podría estar implicado el sistema ubicuitina/ proteasoma (UPS) que controla el ciclo celular mediante degradación de diversos reguladores del ciclo. FBXW7 forma parte del complejo de la ubicuitín ligasa SCF FBXW7 y es responsable de la unión a los sustratos. Esta ligasa ubicuitina para su posterior degradación a oncoproteínas como c-Myc, Ciclina E, Notch1, c-Jun y Mcl1, entre otras. Se han encontrado mutaciones o pérdida de función de FBXW7 en numerosos cánceres, por lo que se considera generalmente que FBXW7 es un supresor tumoral. En este trabajo hemos evaluado el posible papel de FBXW7 en la adquisición de resistencia a taxanos en el cáncer de mama. Estudiamos los niveles de expresión de FBXW7 y de los sustratos Aurora A, Ciclina E y Mcl1 mediante análisis inmunohistoquímico en algunas líneas celulares y en 380 cánceres de mama observando que la disminución de expresión de FBXW7 se correlaciona estadísticamente con un aumento en la expresión de los sustratos estudiados, así como con el grado tumoral más agresivo. También estudiamos el efecto del silenciamiento y la sobreexpresión en algunas líneas celulares confirmando la influencia de FBXW7 sobre los sustratos mencionados y su efecto en la muerte por apoptosis tras tratamiento con paclitaxel. Además, la sobreexpresión de FBXW7 en una línea celular resistente a paclitaxel derivada de células MDA-MB-468 provocó un aumento de la muerte celular y una clara disminución de la proteína anti-apoptótica Mcl1 tras el tratamiento con paclitaxel. Por lo tanto, nuestros datos parecen indicar que FBXW7 podría influir en la adquisición de la resistencia a taxanos principalmente a través de su papel en la regulación de Mcl1.N

NOVEL intronic CAPN3 Roma mutation alters splicing causing RNA mediated decay.

CAPN3 mutations cause a limb girdle muscular dystrophy. Functional characterization of novel mutations facilitates diagnosis of future cases. We have identified a novel (c.1992 + 2T>G) CAPN3 mutation that disrupts the donor splice site of intron 17 splicing out exon 17, with mRNA levels severely reduced or undetectable. The mutation induces a strong change in the 3D structure of the mRNA which supports no-go mRNA decay as the probable mechanism for RNA degradation. The mutation was identified in two unrelated Roma individuals showing a common ancestral origin and founder effect. This is the first Roma CAPN3 mutation to be reported

Variably protease-sensitive prionopathy presenting within ALS/FTD spectrum

We report clinico-pathological features of a 65-year-old woman and a 56-yearold man with a 5-year clinical history who had clinical and neuropathological characteristics of upper and lower motor neuron disease consistent with amyotrophic lateral sclerosis, and a frontotemporal atrophy pattern in case 2 without TDP-43 pathology. Instead, spongiform change and pathological prion protein deposits were observed in several brain regions. No prion protein gene mutations were found. Western blot analysis showed a five-band profile compatible with variably protease-sensitive prionopathy. We conclude that this disease can display prolonged disease duration and clinico-pathological features within the ALS/FTLD spectrum

Variably protease-sensitive prionopathy presenting within ALS/FTD spectrum

We report clinico-pathological features of a 65-year-old woman and a 56-yearold man with a 5-year clinical history who had clinical and neuropathological characteristics of upper and lower motor neuron disease consistent with amyotrophic lateral sclerosis, and a frontotemporal atrophy pattern in case 2 without TDP-43 pathology. Instead, spongiform change and pathological prion protein deposits were observed in several brain regions. No prion protein gene mutations were found. Western blot analysis showed a five-band profile compatible with variably protease-sensitive prionopathy. We conclude that this disease can display prolonged disease duration and clinico-pathological features within the ALS/FTLD spectrum