1,155 research outputs found

    The Myosin II cytoskeleton as a new vulnerability in therapy-resistant melanoma

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    Trabajo presentado en la EACR-AstraZeneca Virtual Conference ‘Drug Tolerant Persister Cells’, celebrada del 07 al 08 de diciembre de 2021.MAPK-targeted therapies (MAPKi) and immune checkpoint blockers (ICB) improve survival of subsets of melanoma patients. However, therapy resistance is a persistent problem. Cross-resistance to MAPKi and ICB may be driven by common transcriptomic alterations in pathways controlling invasion and metastasis. We find that adaptation to treatment and acquisition of resistance to MAPKi involve cytoskeletal remodelling and changes in expression levels in the ROCK-non-muscle Myosin II (NMII) pathway, which is essential for cancer invasion and metastasis. NMII activity is decreased shortly after MAPK is blocked. However, persister cells promptly restore NMII activity to increase survival, and this becomes a vulnerability, since survival of MAPKi- and ICB-resistant cells is highly dependent on ROCK-NMII. Efficacy of MAPKi and ICB can be improved by combination with ROCK inhibitors, which have a dual action by impairing melanoma cell survival (through induction of lethal reactive oxygen species and unresolved DNA damage) and reducing myeloid- and lymphoid-driven immunosuppression, ultimately overcoming cross-resistance. In human tumours, high ROCK-NMII levels identify MAPKi-, ICB-resistant melanomas, and treatment-naïve melanomas with worse prognosis. Therefore, a subset of MAPKi- and ICB-resistant melanomas is more susceptible to ROCK-NMII blockade, suggesting clinical opportunities for combination therapies

    The Myosin II cytoskeleton as a new vulnerability in therapy-resistant melanoma

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    Trabajo presentado en el XIX Congreso de la Sociedad Española de Biología Celular, celebrado en Boadilla del Monte (España) del 26 al 29 de octubre de 2021.MAPK-targeted therapies (MAPKi) and immune checkpoint blockers (ICB) improve survival of subsets of melanoma patients. However, therapy resistance is a persistent problem. Cross-resistance to MAPKi and ICB has been suggested to be driven, in part, by common transcriptomic alterations in pathways controlling invasion and metastasis. We find that adaptation to treatment and acquisition of resistance to MAPKi involve cytoskeletal remodelling and changes in expression levels in the ROCK-Myosin II pathway, which plays a key role in cancer invasion and metastasis. Myosin II activity is decreased shortly after MAPK is blocked. However, resistant cells promptly restore Myosin II activity to increase survival, and this becomes a vulnerability, since survival of MAPKi- and ICB-resistant cells is highly dependent on ROCK-Myosin II. Efficacy of MAPKi and ICB can be improved by combination with ROCK inhibitors, which have a dual action by impairing melanoma cell survival (through induction of lethal reactive oxygen species, unresolved DNA damage and cell cycle arrest) and myeloid- and lymphoid-driven immunosuppression, ultimately overcoming cross-resistance. In human tumours, high ROCK-Myosin II activity and their associated transcriptome identify MAPKi-, ICB-resistant melanomas, and treatment-naïve melanomas with worse prognosis. Therefore, a subset of MAPKi- and ICB-resistant melanomas is intrinsically more susceptible to ROCK-Myosin II inhibition, suggesting clinical opportunities for combination therapies

    A preclinical pipeline to evaluate migrastatics as therapeutic agents in metastatic melanoma

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    © The Author(s) 2021.[Background]: Metastasis is a hallmark of cancer and responsible for most cancer deaths. Migrastatics were defined as drugs interfering with all modes of cancer cell invasion and thus cancers’ ability to metastasise. First anti-metastatic treatments have recently been approved. [Methods]: We used bioinformatic analyses of publicly available melanoma databases. Experimentally, we performed in vitro target validation (including 2.5D cell morphology analysis and mass spectrometric analysis of RhoA binding partners), developed a new traceable spontaneously metastasising murine melanoma model for in vivo validation, and employed histology (haematoxylin/eosin and phospho-myosin II staining) to confirm drug action in harvested tumour tissues. [Results]: Unbiased and targeted bioinformatic analyses identified the Rho kinase (ROCK)-myosin II pathway and its various components as potentially relevant targets in melanoma. In vitro validation demonstrated redundancy of several RhoGEFs upstream of RhoA and confirmed ROCK as a druggable target downstream of RhoA. The anti-metastatic effects of two ROCK inhibitors were demonstrated through in vivo melanoma metastasis tracking and inhibitor effects also confirmed ex vivo by digital pathology. [Conclusions]: We proposed a migrastatic drug development pipeline. As part of the pipeline, we provide a new traceable spontaneous melanoma metastasis model for in vivo quantification of metastasis and anti-metastatic effects by non-invasive imaging.GOF’s lab was supported by Cancer Research UK [C48390/A21153], Worldwide Cancer Research [16-1153], and King’s Health Partners [King’s Medical Research Trust Joint Research Committee studentship to A.V.]. B.F. was supported by a King’s Health Partners studentship to V.S.M. and G.O.F. V.S.M.’s lab was supported by Cancer Research UK [C33043/A12065] and [C33043/A24478] (V.S.M., E.C.M., J.L.O., L.B. and GC), the Royal Society [RG110591] (V.S.M.), The Harry J. Lloyd Charitable Trust (J.L.O. and V.S.M.), the Barts Charity (V.S.M., J.L.O., O.M., I.R.H. and E.C.M.), the Fundacion Alfonso Martin Escudero and Marie Sklodowska-Curie Action [H2020-MSCA-IF-2014-EF-ST] (I.R.H.), and Fundacion Ramon Areces (E.C.M.). F.M. was supported by an MRC Career Development Award (MR/P009417/1). This work was further supported by the Department of Health (DoH) via the National Institute for Health Research (NIHR) Comprehensive Biomedical Research Centre award to King’s Health Partners, and the Wellcome/EPSRC Centre for Medical Engineering [WT203148/Z/16/Z]. Views expressed are those of the authors and not necessarily those of the NHS, NIHR or DoH

    Non-muscle Myosin II reactivation and cytoskeletal remodelling as a new vulnerability in therapy-resistant melanoma

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    Trabajo presentado en el 3rd ASEICA Educational Symposium, celebrado en modalidad virtual del 23 al 25 de noviembre de 2021.MAPK-targeted therapies (MAPKi) and immune checkpoint blockers (ICB) improve survival of subsets of melanoma patients. However, therapy resistance is a persistent problem. Cross-resistance to MAPKi and ICB may be driven by common transcriptomic alterations in pathways controlling invasion and metastasis. Using phosphoproteomic and transcriptomic analyses, we find that adaptation to treatment and acquisition of resistance to MAPKi involve cytoskeletal remodelling and changes in levels in the ROCK-non-muscle Myosin II (NMII) pathway, which is essential for cancer invasion and metastasis. NMII activity is decreased shortly after MAPK is blocked. However, persister cells promptly restore NMII activity to increase survival, and this becomes a vulnerability, since survival of MAPKi- and ICB-resistant cells is highly dependent on ROCK-NMII. Efficacy of MAPKi and ICB can be improved by combination with ROCK inhibitors, which have a dual action by impairing melanoma cell survival (through induction of lethal reactive oxygen species and unresolved DNA damage) and reducing myeloid- and lymphoid-driven immunosuppression, ultimately overcoming cross-resistance in vivo. In human tumours, high ROCK-NMII levels identify MAPKi-, ICB-resistant melanomas, and treatment-naïve melanomas with worse prognosis. Therefore, a subset of MAPKi- and ICB-resistant melanomas is more susceptible to ROCK-NMII blockade, suggesting clinical opportunities for combination therapies

    The Myosin II cytoskeleton as a new vulnerability in therapy-resistant melanoma

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    Trabajo presentado en VIB Conference: Tumor Heterogeneity, Plasticity and Therapy, celebrado en modalidad virtual del 05 al 06 de mayo de 2021.MAPK-targeted therapies (MAPKi) and immune checkpoint blockers (ICB) improve survival of subsets of melanoma patients. However, therapy resistance is a persistent problem. Cross-resistance to MAPKi and ICB has been suggested to be driven, in part, by common transcriptomic alterations in pathways controlling invasion and metastasis. We find that adaptation to treatment and acquisition of resistance to MAPKi involve cytoskeletal remodelling and changes in expression levels in the ROCK-Myosin II pathway, which plays a key role in cancer invasion and metastasis. Myosin II activity is decreased shortly after MAPK is blocked. However, resistant cells promptly restore Myosin II activity to increase survival, and this becomes a vulnerability, since survival of MAPKi- and ICB-resistant cells is highly dependent on ROCK-Myosin II. Efficacy of MAPKi and ICB can be improved by combination with ROCK inhibitors, which have a dual action by impairing melanoma cell survival (through induction of lethal reactive oxygen species and unresolved DNA damage) and myeloid- and lymphoiddriven immunosuppression, overcoming cross-resistance. In human tumours, high ROCK-Myosin II activity and their associated transcriptome identify MAPKi-, ICBresistant melanomas, and treatment-naïve melanomas with worse prognosis. Therefore, a subset of MAPKi- and ICB-resistant melanomas is intrinsically more susceptible to ROCK-Myosin II inhibition, suggesting clinical opportunities for combination therapies

    WNT11-FZD7-DAAM1 signalling supports tumour initiating abilities and melanoma amoeboid invasion

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    Melanoma is a highly aggressive tumour that can metastasize very early in disease progression. Notably, melanoma can disseminate using amoeboid invasive strategies. We show here that high Myosin II activity, high levels of ki-67 and high tumour-initiating abilities are characteristic of invasive amoeboid melanoma cells. Mechanistically, we find that WNT11-FZD7-DAAM1 activates Rho-ROCK1/2-Myosin II and plays a crucial role in regulating tumour-initiating potential, local invasion and distant metastasis formation. Importantly, amoeboid melanoma cells express both proliferative and invasive gene signatures. As such, invasive fronts of human and mouse melanomas are enriched in amoeboid cells that are also ki-67 positive. This pattern is further enhanced in metastatic lesions. We propose eradication of amoeboid melanoma cells after surgical removal as a therapeutic strategy. Amoeboid cells are associated with melanoma invasive capacity. Here, the authors show that the WNT11-FZD7-DAAM1 pathway regulates tumour-initiating potential, invasion and metastasis lead by amoeboid cells in the invasive front of melanoma tumours

    SOMACLONAL VARIATION OF Phanaenopsis sp. var. Dudu PLANTS REGENERATED BY DIRECT SOMATIC EMBRIOGENESIS

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    Actualmente existe una creciente demanda de híbridos de Phalaenopsis sp., por lo cual es necesario desarrollar protocolos de propagación masiva que aseguren altos porcentajes de regeneración clonal tal como la técnica de embriogénesis somática. Así mismo, estudiar la variación genética dentro de las plantas regeneradas ofrece un mayor conocimiento de los alcances del protocolo de micropropagación en relación a la estabilidad genética de los materiales empleados. Objetivo: En el presente trabajo de investigación se evaluó la combinación de tres concentraciones y dos tipos de reguladores de crecimiento vegetal (RCV), la citocinina bencilaminopurina (BA) (1.0, 2.0 y 3.0 mgL-1) en combinación con tres concentraciones de ácido 2,4-diclorofenoxiacético (2,4-D) (3.0, 4.0 y 5.0 mgL-1), para la inducción de embriones somáticos, además, se analizó la estabilidad genética de las plántulas regeneradas mediante marcadores moleculares tipo RAPD (Random Amplified Polymorphic DNA, por sus siglas en inglés). Metodología: La embriogénesis somática se indujo a partir de explantes de hoja con distintos grados de desarrollo: primera hoja se consideró como explante maduro (PH) y la tercera hoja como explante joven (TH), obtenidas de una plántula de Phalaenopsis sp. var. Dudú cultivadas in vitro, de 15-20 cm de altura. Resultados: El mayor número de plantas regeneradas fue de 29.8 a los 135 días después de iniciado el cultivo (ddic) con 2.0 y 5.0 mgL-1 de BA y 2,4-D, respectivamente, utilizando como explante la TH en la respuesta morfogenética de los explantes regenerados, se observó una correlación entre la edad del explante y la concentración de RCV. El análisis de la variación genética mostró cambios en los patrones de bandeo, observando bandas polimórficas con los cuatro iniciadores utilizados, aludiendo variación somaclonal en las plantas regeneradas. Implicaciones: Los resultados obtenidos aportan una alternativa de regeneración, además de ofrecer una metodología para iniciar programas de mejoramiento genético en Phalaenopsis sp. var. Dudú. Conclusiones: Se logró la regeneración in vitro de Phalaenopsis sp. var. Dudú mediante embriogénesis somática, así como la detección de cambios genéticos en el material regenerado.Nowadays, a growing demand for hybrids of Phalaenopsis sp. exists to satisfy this demand it is necessary to develop protocols for massive propagation that ensure high percentages of clonal regeneration, such as somatic embryogenesis. Besides, studying genetic variation within regenerated plants offers a greater understanding of the suitability of the micropropagation protocol in relation with genetic stability of the materials used. Objective: The present research work aimed to evaluate three concentrations of two types of plant growth regulators (RCV). 6- benzylaminopurine cytokinin (BA) (1.0, 2.0 y 3.0 mgL-1) in combination with three concentrations of 2,4- diclorofenoxiacetic acid (2,4-D) (3.0, 4.0, 5.0 mgL-1), for the induction of somatic embryos. In addition, the genetic stability of the regenerated plants was analyzed using molecular markers type RAPD (Random Amplified Polymorphic DNA). Methodology: The induction of somatic embryogenesis was induced from two leaf explants with different stages of develop from 15-20 cm in height Phalaenopsis sp. var. Dudú seedlings, cultivated in vitro; first leaf as mature explant (PH) and third leaf as young explant (TH). Results: The highest number of regenerated plants was 29.8 at 135 days after the start of the culture (ddic) with 2.0 and 5.0 mgL-1 of BA and 2,4-D, respectively, using TH as explant. In the morphogenetic response of the regenerated explants, a correlation was observed between the age of the explant and the RCV concentration. Polymorphic bands were observed with the four primers used, indicating somaclonal variation in regenerated plants. Implications: The results obtained provide an alternative for regeneration, as well as offering a methodology to initiate genetic improvement programs in Phalaenopsis sp. var. Dudú. Conclusions: In vitro regeneration of Phalaenopsis sp. var. Dudú by somatic embryogenesis was achieved, as well as the analysis of the genetic integrity of the regenerated material.UNIVERSIDAD AUTONOMA DEL ESTADO DE MEXIC

    Neutrophil infiltration regulates clock-gene expression to organize daily hepatic metabolism.

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    Liver metabolism follows diurnal fluctuations through the modulation of molecular clock genes. Disruption of this molecular clock can result in metabolic disease but its potential regulation by immune cells remains unexplored. Here, we demonstrated that in steady state, neutrophils infiltrated the mouse liver following a circadian pattern and regulated hepatocyte clock-genes by neutrophil elastase (NE) secretion. NE signals through c-Jun NH2-terminal kinase (JNK) inhibiting fibroblast growth factor 21 (FGF21) and activating Bmal1 expression in the hepatocyte. Interestingly, mice with neutropenia, defective neutrophil infiltration or lacking elastase were protected against steatosis correlating with lower JNK activation, reduced Bmal1 and increased FGF21 expression, together with decreased lipogenesis in the liver. Lastly, using a cohort of human samples we found a direct correlation between JNK activation, NE levels and Bmal1 expression in the liver. This study demonstrates that neutrophils contribute to the maintenance of daily hepatic homeostasis through the regulation of the NE/JNK/Bmal1 axis.BGT and MC were fellows of the FPI: Severo Ochoa CNIC program (SVP-2013–067639) and (BES-2017–079711) respectively. IN was funded by EFSD/Lilly grants (2017 and 2019), the CNIC IPP FP7 Marie Curie Programme (PCOFUND-2012–600396), EFSD Rising Star award (2019), JDC-2018-Incorporación (MIN/JDC1802). T-L was a Juan de la Cierva fellow (JCI2011–11623). C.F has a Sara Borrell contract (CD19/00078). RJD is an Investigator of the Howard Hughes Medical Institute. This work was funded by the following grants to GS: funding from the European Union’s Seventh Framework Programme (FP7/2007-2013) under grant agreement n˚ ERC 260464, EFSD/Lilly European Diabetes Research Programme Dr Sabio, 2017 Leonardo Grant for Researchers and Cultural Creators, BBVA Foundation (Investigadores-BBVA-2017) IN[17] _BBM_BAS_0066, MINECO-FEDER SAF2016-79126-R and PID2019-104399RB-I00 , EUIN201785875, Comunidad de Madrid IMMUNOTHERCAN-CM S2010/BMD-2326 and B2017/BMD-3733 and Fundación AECC AECC PROYE19047SABI and AECC: INVES20026LEIV to ML. MM was funded by ISCIII and FEDER PI16/01548 and Junta de Castilla y León GRS 1362/A/16 and INT/M/17/17 and JL-T by Junta de Castilla y León GRS 1356/A/16 and GRS 1587/A/17. The study was additionally funded by MEIC grants to ML (MINECO-FEDER-SAF2015-74112-JIN) AT-L (MINECO-FEDERSAF2014-61233-JIN), RJD: Grant DK R01 DK107220 from the National Institutes of Health. AH: (SAF2015-65607-R). The CNIC is supported by the Instituto de Salud Carlos III (ISCIII), the Ministerio de Ciencia, Innovación y Universidades (MCNU) and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015–0505).S

    RET Fusion Testing in Patients With NSCLC: The RETING Study

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    Introduction: RET inhibitors with impressive overall response rates are now available for patients with NSCLC, yet the identi fication of RET fusions remains a dif ficult challenge. Most guidelines encourage the upfront use of next -generation sequencing (NGS), or alternatively, fluorescence in situ hybridization (FISH) or reverse transcriptase-polymerase chain reaction (RT-PCR) when NGS is not possible or available. Taken together, the suboptimal performance of single-analyte assays to detect RET fusions, although consistent with the notion of encouraging universal NGS, is currently widening some of the clinical practice gaps in the implementation of predictive biomarkers in patients with advanced NSCLC. Methods: This situation prompted us to evaluate several RET assays in a large multicenter cohort of RET fusion -positive NSCLC (n 1 / 4 38) to obtain real -world data. In addition to RNA -based NGS (the criterion standard method), all positive specimens underwent break -apart RET FISH with two different assays and were also tested by an RT-PCR assay. Results: The most common RET partners were KIF5B (78.9%), followed by CCDC6 (15.8%). The two RET NGSpositive but FISH -negative samples contained a KIF5B(15)RET(12) fusion. The three RET fusions not identi fied with RT-PCR were AKAP13(35)-RET(12) , KIF5B(24)-RET(9) and KIF5B(24)-RET(11) . All three false -negative RT-PCR cases were FISH -positive, exhibited a typical break -apart pattern, and contained a very high number of positive tumor cells with both FISH assays. Signet ring cells, psammoma bodies, and pleomorphic features were frequently observed (in 34.2%, 39.5%, and 39.5% of tumors, respectively). Conclusions: In-depth knowledge of the advantages and disadvantages of the different RET testing methodologies could help clinical and molecular tumor boards implement and maintain sensible algorithms for the rapid and effective detection of RET fusions in patients with NSCLC. The likelihood of RET false -negative results with both FISH and RT-PCR reinforces the need for upfront NGS in patients with NSCLC. (c) 2024 The Authors. Published by Elsevier Inc. on behalf of the International Association for the Study of Lung Cancer. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/)

    Heterozygous and Homozygous Variants in SORL1 Gene in Alzheimer's Disease Patients: Clinical, Neuroimaging and Neuropathological Findings

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    In the last few years, the SORL1 gene has been strongly implicated in the development of Alzheimer’s disease (AD). We performed whole-exome sequencing on 37 patients with early-onset dementia or family history suggestive of autosomal dominant dementia. Data analysis was based on a custom panel that included 46 genes related to AD and dementia. SORL1 variants were present in a high proportion of patients with candidate variants (15%, 3/20). We expand the clinical manifestations associated with the SORL1 gene by reporting detailed clinical and neuroimaging findings of six unrelated patients with AD and SORL1 mutations. We also present for the first time a patient with the homozygous truncating variant c.364C>T (p.R122*) in SORL1, who also had severe cerebral amyloid angiopathy. Furthermore, we report neuropathological findings and immunochemistry assays from one patient with the splicing variant c.4519+5G>A in the SORL1 gene, in which AD was confirmed by neuropathological examination. Our results highlight the heterogeneity of clinical presentation and familial dementia background of SORL1-associated AD and suggest that SORL1 might be contributing to AD development as a risk factor gene rather than as a major autosomal dominant gene.This work was supported by the Instituto de Salud Carlos III (PI17/01067) and AGAUR from the Autonomous Catalan Government (2017SGR1134). Dr. Víctor Antonio Blanco-Palmero is supported by the Instituto de Salud Carlos III (ISCIII, Spanish Biomedical Research Institute) through a “Río Hortega” contract (CM18/0095). Dr. Sara Llamas-Velasco is supported by the Instituto de Salud Carlos III (ISCIII; Spanish Biomedical Research Institute) through a “Juan Rodés” contract (JR 18/00046).S
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