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Although p53 protein aggregates have been observed in cancer cell lines and tumour tissue, their impact in cancer remains largely unknown. Here, we extensively screened for p53 aggregation phenotypes in tumour biopsies, and identified nuclear inclusion bodies (nIBs) of transcriptionally inactive mutant or wild-type p53 as the most frequent aggregation-like phenotype across six different cancer types. p53-positive nIBs co-stained with nuclear aggregation markers, and shared molecular hallmarks of nIBs commonly found in neurodegenerative disorders. In cell culture, tumour-associated stress was a strong inducer of p53 aggregation and nIB formation. This was most prominent for mutant p53, but could also be observed in wild-type p53 cell lines, for which nIB formation correlated with the loss of p53's transcriptional activity. Importantly, protein aggregation also fuelled the dysregulation of the proteostasis network in the tumour cell by inducing a hyperactivated, oncogenic heat-shock response, to which tumours are commonly addicted, and by overloading the proteasomal degradation system, an observation that was most pronounced for structurally destabilized mutant p53. Patients showing tumours with p53-positive nIBs suffered from a poor clinical outcome, similar to those with loss of p53 expression, and tumour biopsies showed a differential proteostatic expression profile associated with p53-positive nIBs. p53-positive nIBs therefore highlight a malignant state of the tumour that results from the interplay between (1) the functional inactivation of p53 through mutation and/or aggregation, and (2) microenvironmental stress, a combination that catalyses proteostatic dysregulation. This study highlights several unexpected clinical, biological and therapeutically unexplored parallels between cancer and neurodegeneration. Copyright (C) 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

[EN] The present invention provides mutated variants of bacteriophage phi29 DNA polymerase having greater activity than the natural enzyme at high temperatures (greater than 30°C, preferably 40-42°C). Said variants are, therefore, more thermoactive and have a higher amplification speed in comparison with the natural enzyme, significantly improving the efficiency of the amplification reactions in which they are used. Additionally, the variants of the invention enable the amplification of limiting quantities of template DNA, in the order of a picogram. The invention also provides a method for amplifying template DNA, wherein said variants, and a kit comprising said variants, together with the elements necessary for carrying out the method, are used., [ES] La presente invención proporciona variantes mutadas de la ADN polimerasa del bacteriófago phi29 que presentan mayor actividad que la enzima natural a temperaturas elevadas (superiores a 30ºC, preferiblemente a 40-42ºC).Dichas variantes son, por tanto, más termoactivas y presentan una mayor velocidad de amplificación en comparación con la enzima natural, mejorando significativamente el rendimiento de las reacciones de amplificación en las que se emplean. Además, las variantes de la invención permiten amplificar cantidades limitantes de ADN molde, del orden de picogramos. La invención también proporciona un método para la amplificación de un ADN molde donde se emplean dichas variantes y un kit que comprende dichas variantes junto con los elementos necesarios para llevar a cabo dicho método., Consejo Superior de Investigaciones Científicas (España), Fundació Centre de Regulació Genómica, Institució Catalana de Recerca i Estudis Avançats, A1 Solicitud de patente con informe sobre el estado de la técnica

[EN] The present invention provides mutated variants of bacteriophage phi29 DNA polymerase having greater activity than the natural enzyme at high temperatures (greater than 30°C, preferably 40-42°C). Said variants are, therefore, more thermoactive and have a higher amplification speed in comparison with the natural enzyme, significantly improving the efficiency of the amplification reactions in which they are used. Additionally, the variants of the invention enable the amplification of limiting quantities of template DNA, in the order of a picogram. The invention also provides a method for amplifying template DNA, wherein said variants, and a kit comprising said variants, together with the elements necessary for carrying out the method, are used. [ES] La presente invención proporciona variantes mutadas de la ADN polimerasa del bacteriófago phi29 que presentan mayor actividad que la enzima natural a temperaturas elevadas (superiores a 30ºC, preferiblemente a 40-42ºC).Dichas variantes son, por tanto, más termoactivas y presentan una mayor velocidad de amplificación en comparación con la enzima natural, mejorando significativamente el rendimiento de las reacciones de amplificación en las que se emplean. Además, las variantes de la invención permiten amplificar cantidades limitantes de ADN molde, del orden de picogramos. La invención también proporciona un método para la amplificación de un ADN molde donde se emplean dichas variantes y un kit que comprende dichas variantes junto con los elementos necesarios para llevar a cabo dicho método. Peer reviewed Consejo Superior de Investigaciones Científicas (España), Fundació Centre de Regulació Genómica, Institució Catalana de Recerca i Estudis Avançats A1 Solicitud de patente con informe sobre el estado de la técnica