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1.
Pharmacol Res ; 175: 105959, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34756924

RESUMEN

Glioblastomas (GBMs), the most frequent brain tumours, are highly invasive and their prognosis is still poor despite the use of combination treatment. MG624 is a 4-oxystilbene derivative that is active on α7- and α9-containing neuronal nicotinic acetylcholine receptor (nAChR) subtypes. Hybridisation of MG624 with a non-nicotinic resveratrol-derived pro-oxidant mitocan has led to two novel compounds (StN-4 and StN-8) that are more potent than MG624 in reducing the viability of GBM cells, but less potent in reducing the viability of mouse astrocytes. Functional analysis of their activity on α7 receptors showed that StN-4 is a silent agonist, whereas StN-8 is a full antagonist, and neither alters intracellular [Ca2+] levels when acutely applied to U87MG cells. After 72 h of exposure, both compounds decreased U87MG cell proliferation, and pAKT and oxphos ATP levels, but only StN-4 led to a significant accumulation of cells in phase G1/G0 and increased apoptosis. One hour of exposure to either compound also decreased the mitochondrial and cytoplasmic ATP production of U87MG cells, and this was not paralleled by any increase in the production of reactive oxygen species. Knocking down the α9 subunit (which is expressed at relatively high levels in U87MG cells) decreased the potency of the effects of both compounds on cell viability, but cell proliferation, ATP production, pAKT levels were unaffected by the presence of the noncell-permeable α7/α9-selective antagonist αBungarotoxin. These last findings suggest that the anti-tumoral effects of StN-4 and StN-8 on GBM cells are not only due to their action on nAChRs, but also to other non-nicotinic mechanisms.


Asunto(s)
Compuestos de Amonio/farmacología , Antineoplásicos/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Glioblastoma/tratamiento farmacológico , Estilbenos/farmacología , Adenosina Trifosfato/metabolismo , Animales , Astrocitos/efectos de los fármacos , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Fenómenos Fisiológicos Celulares/efectos de los fármacos , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Ligandos , Ratones , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptores Nicotínicos/genética , Receptor Nicotínico de Acetilcolina alfa 7/genética
2.
Int J Mol Sci ; 23(7)2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35408823

RESUMEN

CHRFAM7A is a relatively recent and exclusively human gene arising from the partial duplication of exons 5 to 10 of the α7 neuronal nicotinic acetylcholine receptor subunit (α7 nAChR) encoding gene, CHRNA7. CHRNA7 is related to several disorders that involve cognitive deficits, including neuropsychiatric, neurodegenerative, and inflammatory disorders. In extra-neuronal tissues, α7nAChR plays an important role in proliferation, differentiation, migration, adhesion, cell contact, apoptosis, angiogenesis, and tumor progression, as well as in the modulation of the inflammatory response through the "cholinergic anti-inflammatory pathway". CHRFAM7A translates the dupα7 protein in a multitude of cell lines and heterologous systems, while maintaining processing and trafficking that are very similar to the full-length form. It does not form functional ion channel receptors alone. In the presence of CHRNA7 gene products, dupα7 can assemble and form heteromeric receptors that, in order to be functional, should include at least two α7 subunits to form the agonist binding site. When incorporated into the receptor, in vitro and in vivo data showed that dupα7 negatively modulated α7 activity, probably due to a reduction in the number of ACh binding sites. Very recent data in the literature report that the presence of the duplicated gene may be responsible for the translational gap in several human diseases. Here, we will review the studies that have been conducted on CHRFAM7A in different pathologies, with the intent of providing evidence regarding when and how the expression of this duplicated gene may be beneficial or detrimental in the pathogenesis, and eventually in the therapeutic response, to CHRNA7-related neurological and non-neurological diseases.


Asunto(s)
Genes Duplicados , Inflamación , Enfermedades Neurodegenerativas , Receptor Nicotínico de Acetilcolina alfa 7 , Sitios de Unión , Humanos , Inflamación/genética , Inflamación/metabolismo , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/metabolismo , Neuronas/metabolismo , Isoformas de Proteínas/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7/genética , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo
3.
Int J Mol Sci ; 23(9)2022 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-35563209

RESUMEN

Heterozygous mutations of the transcription factor PHOX2B are responsible for Congenital Central Hypoventilation Syndrome, a neurological disorder characterized by inadequate respiratory response to hypercapnia and life-threatening hypoventilation during sleep. Although no cure is currently available, it was suggested that a potent progestin drug provides partial recovery of chemoreflex response. Previous in vitro data show a direct molecular link between progestins and PHOX2B expression. However, the mechanism through which these drugs ameliorate breathing in vivo remains unknown. Here, we investigated the effects of chronic administration of the potent progestin drug Etonogestrel (ETO) on respiratory function and transcriptional activity in adult female rats. We assessed respiratory function with whole-body plethysmography and measured genomic changes in brain regions important for respiratory control. Our results show that ETO reduced metabolic activity, leading to an enhanced chemoreflex response and concurrent increased breathing cycle variability at rest. Furthermore, ETO-treated brains showed reduced mRNA and protein expression of PHOX2B and its target genes selectively in the dorsal vagal complex, while other areas were unaffected. Histological analysis suggests that changes occurred in the solitary tract nucleus (NTS). Thus, we propose that the NTS, rich in both progesterone receptors and PHOX2B, is a good candidate for ETO-induced respiratory modulation.


Asunto(s)
Apnea Central del Sueño , Núcleo Solitario , Animales , Desogestrel , Femenino , Proteínas de Homeodominio/metabolismo , Hipoventilación/congénito , Hipoventilación/genética , Mutación , Progestinas/farmacología , Ratas , Apnea Central del Sueño/genética , Núcleo Solitario/metabolismo
4.
Ann Surg Oncol ; 28(11): 6071-6082, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33881656

RESUMEN

BACKGROUND: The impact of patient demographics and local therapy choice on arm morbidity in young breast cancer patients is understudied despite its importance given the long survivorship period. This study assessed patient-reported arm morbidity in the Young Women's Breast Cancer Study (YWS), a prospective cohort study. METHODS: From 2006 to 2016, 1302 women with breast cancer diagnosed at the age of 40 years or younger enrolled in the YWS. The participants regularly complete surveys. The response rates are higher than 86%. Using the Breast Cancer Prevention Trial Checklist, this study examined the prevalence of patient-reported postoperative arm swelling and decreased range of motion (ROM) 1 year after diagnosis, stratified by local therapy strategy, in patients who had surgery for stages 1 to 3 disease. Logistic regression analysis was used to identify risk factors for arm morbidity. RESULTS: Among 888 eligible participants (median age, 37 years), 14% reported arm swelling and 34% reported decreased ROM at 1 year. Arm swelling was reported by 23.6% of the patients who had axillary lymph node dissection (ALND) and 24.6% of the patients who received ALND and post-mastectomy radiation therapy (PMRT). In the multivariable analysis, the patients who reported being financially uncomfortable or who had ALND were at higher risk of arm swelling at 1 year. Being overweight, receiving ALND after sentinel lymph node biopsy, and receiving PMRT were associated with decreased ROM at 1 year. CONCLUSION: High rates of self-reported arm morbidity in young breast cancer survivors were reported, particularly in patients receiving ALND and PMRT. Attention to the risks and benefits of differing local therapy strategies for ALND and PMRT patients is warranted.


Asunto(s)
Neoplasias de la Mama , Adulto , Brazo , Axila , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/cirugía , Femenino , Humanos , Escisión del Ganglio Linfático/efectos adversos , Metástasis Linfática , Mastectomía , Morbilidad , Estudios Prospectivos , Biopsia del Ganglio Linfático Centinela
5.
Pharmacol Res ; 173: 105874, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34500063

RESUMEN

Acetyl-L-carnitine (ALC) is an endogenous molecule that not only plays a role in energy metabolism, but also has antioxidant properties, protects from oxidative stress, modulates brain neurotransmitters such as acetylcholine, serotonin and dopamine, and acts on neurotrophic factors such as nerve growth factor (NGF) and metabotropic glutamate (mGlu) receptors by means of epigenetic mechanisms. Importantly, it induces mGlu2 expression at nerve terminals, thus giving rise to analgesia and preventing spinal sensitisation. It has also been found to have even long-term neurotrophic and analgesic activity in experimental models of chronic inflammatory and neuropathic pain. The aim of this narrative review is to summarise the current evidence regarding the use of ALC in patients with chronic pain, and cognitive and mood disorders, and investigate the rationale underlying its use in patients with fibromyalgia syndrome, which is characterised by nociplastic changes that increase the sensitivity of the nervous system to pain.


Asunto(s)
Acetilcarnitina/uso terapéutico , Analgésicos/uso terapéutico , Dolor Crónico/tratamiento farmacológico , Animales , Antidepresivos/uso terapéutico , Humanos , Fármacos Neuroprotectores/uso terapéutico
6.
Pharmacol Res ; 163: 105336, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33276105

RESUMEN

Glioblastomas (GBMs), the most frequent and aggressive human primary brain tumours, have altered cell metabolism, and one of the strongest indicators of malignancy is an increase in choline compounds. Choline is also a selective agonist of some neuronal nicotinic acetylcholine receptor (nAChR) subtypes. As little is known concerning the expression of nAChR in glioblastoma cells, we analysed in U87MG human grade-IV astrocytoma cell line and GBM5 temozolomide-resistant glioblastoma cells selected from a cancer stem cell-enriched culture, molecularly, pharmacologically and functionally which nAChR subtypes are expressed and,whether choline and nicotine can affect GBM cell proliferation. We found that U87MG and GBM5 cells express similar nAChR subtypes, and choline and nicotine increase their proliferation rate and activate the anti-apoptotic AKT and pro-proliferative ERK pathways. These effects are blocked by the presence of non-cell-permeable peptide antagonists selective for α7- and α9-containing nicotinic receptors. siRNA-mediated silencing of α7 or α9 subunit expression also selectively prevents the effects of nicotine and choline on GBM cell proliferation. Our findings indicate that nicotine and choline activate the signalling pathways involved in the proliferation of GBM cells, and that these effects are mediated by α7 and α9-containing nAChRs. This suggests that these nicotinic receptors may contribute to the aggressive behaviour of this tumor and may indicate new therapeutic strategies against high-grade human brain tumours.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Colina/farmacología , Glioblastoma/metabolismo , Nicotina/farmacología , Receptores Nicotínicos/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Interferente Pequeño/genética , Receptores Nicotínicos/genética , Receptor Nicotínico de Acetilcolina alfa 7/genética
7.
Aging Clin Exp Res ; 33(4): 823-834, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31583530

RESUMEN

Neuroinflammation and cholinergic dysfunction, leading to cognitive impairment, are hallmarks of aging and neurodegenerative disorders, including Alzheimer's disease (AD). Acetylcholinesterase inhibitors (AChEI), the symptomatic therapy in AD, attenuate and delay the cognitive deficit by enhancing cholinergic synapses. The α7 nicotinic acetylcholine (ACh) receptor has shown a double-edged sword feature, as it binds with high affinity Aß1-42, promoting intracellular accumulation and Aß-induced tau phosphorylation, but also exerts neuroprotection by stimulating anti-apoptotic pathways. Moreover, it mediates peripheral and central anti-inflammatory response, being the effector player of the activation of the cholinergic anti-inflammatory pathway (CAIP), that, by decreasing the release of TNF-α, IL-1ß, and IL-6, it may have a role in improving cognition. The finding in preclinical models that, in addition to their major function (choline esterase inhibition) AChEIs have neuroprotective properties mediated via α7nAChR and modulate innate immunity, possibly as a result of the increased availability of acetylcholine activating the CAIP, pave the way for new pharmacological intervention in AD and other neurological disorders that are characterized by neuroinflammation. CHRFAM7A is a human-specific gene acting as a dominant negative inhibitor of α7nAChR function, also suggesting a role in affecting human cognition and memory by altering α7nAChR activities in the central nervous system (CNS). This review will summarize the current knowledge on the cholinergic anti-inflammatory pathway in aging-related disorders, and will argue that the presence of the human-restricted CHRFAM7A gene might play a fundamental role in the regulation of CAIP and in the response to AChEI.


Asunto(s)
Enfermedad de Alzheimer , Inhibidores de la Colinesterasa , Envejecimiento , Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores de la Colinesterasa/farmacología , Inhibidores de la Colinesterasa/uso terapéutico , Humanos , Neuroinmunomodulación , Receptor Nicotínico de Acetilcolina alfa 7
8.
Exp Cell Res ; 370(2): 671-679, 2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-30036539

RESUMEN

The paired-like homeobox 2B gene (PHOX2B) encodes a key transcription factor that plays a role in the development of the autonomic nervous system and the neural structures involved in controlling breathing. In humans, PHOX2B over-expression plays a role in the pathogenesis of tumours arising from the sympathetic nervous system such as neuroblastomas, and heterozygous PHOX2B mutations cause Congenital Central Hypoventilation Syndrome (CCHS), a life-threatening neurocristopathy characterised by the defective autonomic control of breathing and involving altered CO2/H+ chemosensitivity. The recovery of CO2/H+ chemosensitivity and increased ventilation have been observed in two CCHS patients using the potent contraceptive progestin desogestrel. Given the central role of PHOX2B in the pathogenesis of CCHS, and the progesterone-mediated effects observed in the disease, we generated progesterone-responsive neuroblastoma cells, and evaluated the effects of 3-Ketodesogestrel (3-KDG), the biologically active metabolite of desogestrel, on the expression of PHOX2B and its target genes. Our findings demonstrate that, through progesterone nuclear receptor PR-B, 3-KDG down-regulates PHOX2B gene expression, by a post-transcriptional mechanism, and its target genes and open up the possibility that this mechanism may contribute to the positive effects observed in some CCHS patients.


Asunto(s)
Desogestrel/farmacología , Proteínas de Homeodominio/efectos de los fármacos , Células-Madre Neurales/efectos de los fármacos , Progesterona/genética , Factores de Transcripción/efectos de los fármacos , Núcleo Celular/metabolismo , Regulación hacia Abajo/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Hipoventilación/congénito , Hipoventilación/genética , Células-Madre Neurales/metabolismo , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/genética , Apnea Central del Sueño/genética , Factores de Transcripción/metabolismo
9.
Hum Mutat ; 39(2): 219-236, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29098737

RESUMEN

Heterozygous mutations in the PHOX2B gene are causative of congenital central hypoventilation syndrome (CCHS), a neurocristopathy characterized by defective autonomic control of breathing due to the impaired differentiation of neural crest cells. Among PHOX2B mutations, polyalanine (polyAla) expansions are almost exclusively associated with isolated CCHS, whereas frameshift variants, although less frequent, are often more severe than polyAla expansions and identified in syndromic CCHS. This article provides a complete review of all the frameshift mutations identified in cases of isolated and syndromic CCHS reported in the literature as well as those identified by us and not yet published. These were considered in terms of both their structure, whether the underlying indels induced frameshifts of either 1 or 2 steps ("frame 2" and "frame 3" mutations respectively), and clinical associations. Furthermore, we evaluated the structural and functional effects of one "frame 3" mutation identified in a patient with isolated CCHS, and one "frame 2" mutation identified in a patient with syndromic CCHS, also affected with Hirschsprung's disease and neuroblastoma. The data thus obtained confirm that the type of translational frame affects the severity of the transcriptional dysfunction and the predisposition to isolated or syndromic CCHS.


Asunto(s)
Mutación del Sistema de Lectura/genética , Proteínas de Homeodominio/química , Proteínas de Homeodominio/genética , Hipoventilación/congénito , Apnea Central del Sueño/genética , Factores de Transcripción/química , Factores de Transcripción/genética , Ensayo de Cambio de Movilidad Electroforética , Células HeLa , Humanos , Hipoventilación/genética , Hipoventilación/metabolismo , Microscopía Fluorescente , Mutación , Apnea Central del Sueño/metabolismo
10.
J Biol Chem ; 291(25): 13375-93, 2016 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-27129232

RESUMEN

Heterozygous mutations of the human PHOX2B gene, a key regulator of autonomic nervous system development, lead to congenital central hypoventilation syndrome (CCHS), a neurodevelopmental disorder characterized by a failure in the autonomic control of breathing. Polyalanine expansions in the 20-residues region of the C terminus of PHOX2B are the major mutations responsible for CCHS. Elongation of the alanine stretch in PHOX2B leads to a protein with altered DNA binding, transcriptional activity, and nuclear localization and the possible formation of cytoplasmic aggregates; furthermore, the findings of various studies support the idea that CCHS is not due to a pure loss of function mechanism but also involves a dominant negative effect and/or toxic gain of function for PHOX2B mutations. Because PHOX2B forms homodimers and heterodimers with its paralogue PHOX2A in vitro, we tested the hypothesis that the dominant negative effects of the mutated proteins are due to non-functional interactions with the wild-type protein or PHOX2A using a co-immunoprecipitation assay and the mammalian two-hybrid system. Our findings show that PHOX2B forms homodimers and heterodimerizes weakly with mutated proteins, exclude the direct involvement of the polyalanine tract in dimer formation, and indicate that mutated proteins retain partial ability to form heterodimers with PHOX2A. Moreover, in this study, we investigated the effects of the longest polyalanine expansions on the homeodomain-mediated nuclear import, and our data clearly show that the expanded C terminus interferes with this process. These results provide novel insights into the effects of the alanine tract expansion on PHOX2B folding and activity.


Asunto(s)
Núcleo Celular/enzimología , Proteínas de Homeodominio/metabolismo , Hipoventilación/congénito , Apnea Central del Sueño/enzimología , Factores de Transcripción/metabolismo , Transporte Activo de Núcleo Celular , Secuencia de Bases , Células HeLa , Proteínas de Homeodominio/genética , Humanos , Hipoventilación/enzimología , Hipoventilación/genética , Péptidos/genética , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Multimerización de Proteína , Apnea Central del Sueño/genética , Factores de Transcripción/genética , Expansión de Repetición de Trinucleótido
11.
Exp Cell Res ; 342(1): 62-71, 2016 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-26902400

RESUMEN

PHOX2B and its paralogue gene PHOX2A are two homeodomain proteins in the network regulating the development of autonomic ganglia that have been associated with the pathogenesis of neuroblastoma (NB), because of their over-expression in different NB cell lines and tumour samples. We used the SK-N-BE(2)C cell line to show that all-trans retinoic acid (ATRA), a drug that is widely used to inhibit growth and induce differentiation in NBs, regulates both PHOX2A and PHOX2B expression, albeit by means of different mechanisms: it up-regulates PHOX2A and down-regulates PHOX2B. Both mechanisms act at transcriptional level, but prolonged ATRA treatment selectively degrades the PHOX2A protein, whereas the corresponding mRNA remains up-regulated. Further, we show that PHOX2A is capable of modulating PHOX2B expression, but this mechanism is not involved in the PHOX2B down-regulation induced by retinoic acid. Our findings demonstrate that PHOX2A expression is finely controlled during retinoic acid differentiation and this, together with PHOX2B down-regulation, reinforces the idea that they may be useful biomarkers for NB staging, prognosis and treatment decision making.


Asunto(s)
Proteínas de Homeodominio/metabolismo , Factores de Transcripción/metabolismo , Transcripción Genética/efectos de los fármacos , Tretinoina/farmacología , Secuencia de Bases , Diferenciación Celular , Línea Celular Tumoral , Inducción Enzimática/efectos de los fármacos , Represión Enzimática/efectos de los fármacos , Proteínas de Homeodominio/genética , Humanos , Neuroblastoma , Complejo de la Endopetidasa Proteasomal/metabolismo , Proteolisis , Elementos de Respuesta , Factores de Transcripción/genética
12.
Expert Opin Pharmacother ; 25(8): 999-1017, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38853631

RESUMEN

INTRODUCTION: This review delves into Fibromyalgia Syndrome (FMS), a chronic pain condition demanding thorough understanding for precise diagnosis and treatment. Yet, a definitive pharmacological solution for FMS remains elusive. AREAS COVERED: In this article, we systematically analyze various pharmacotherapeutic prospects for FMS treatment, organized into sections based on the stage of drug development and approval. We begin with an overview of FDA-approved drugs, discussing their efficacy in FMS treatment. Next, we delve into other medications currently used for FMS but still undergoing further study, including opioids and muscle relaxants. Further, we evaluate the evidence behind medications that are currently under study, such as cannabinoids and naltrexone. Lastly, we explore new drugs that are in phase II trials. Our research involved a thorough search on PUBMED, Google Scholar, and clinicaltrials.gov. We also discuss the action mechanisms of these drugs and their potential use in specific patient groups. EXPERT OPINION: A focus on symptom-driven, combination therapy is crucial in managing FMS. There is also a need for ongoing research into drugs that target neuroinflammation, immunomodulation, and the endocannabinoid system. Bridging the gap between benchside research and clinical application is challenging, but it holds potential for more targeted and effective treatment strategies.


Asunto(s)
Desarrollo de Medicamentos , Fibromialgia , Fibromialgia/tratamiento farmacológico , Humanos , Animales , Dolor Crónico/tratamiento farmacológico , Aprobación de Drogas , Analgésicos Opioides/uso terapéutico
13.
Best Pract Res Clin Rheumatol ; : 101970, 2024 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-39004557

RESUMEN

Pain is a significant issue in rheumatoid arthritis (RA) and psoriatic arthritis (PSA) and can have a negative impact on patients' quality of life. Despite optimal control of inflammatory disease, residual chronic pain remains a major unmet medical need in RA. Pain in RA can be secondary to inflammation but can also generate neuroendocrine responses that initiate neurogenic inflammation and enhance cytokine release, leading to persistent hyperalgesia. In addition to well-known cytokines such as TNFα and IL-6, other cytokines and the JAK-STAT pathway play a role in pain modulation and inflammation. The development of chronic pain in RA involves processes beyond inflammation or structural damage. Residual pain is often observed in patients even after achieving remission or low disease activity, suggesting the involvement of non-inflammatory and central sensitization mechanisms. Moreover, fibromyalgia syndrome (FMS) is prevalent in RA patients and may contribute to persistent pain. Factors such as depression, sleep disturbance, and pro-inflammatory cytokines may contribute to the development of fibromyalgia in RA. It is essential to identify and diagnose concomitant FMS in RA patients to better manage their symptoms. Further research is needed to unravel the complexities of pain in RA. Finally, recent studies have shown that JAK inhibitors effectively reduce residual pain in RA patients, suggesting pain-reducing effects independent of their anti-inflammatory properties.

14.
Chem Sci ; 15(23): 8858-8872, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38873078

RESUMEN

An expansion of poly-alanine up to +13 residues in the C-terminus of the transcription factor PHOX2B underlies the onset of congenital central hypoventilation syndrome (CCHS). Recent studies demonstrated that the alanine tract expansion influences PHOX2B folding and activity. Therefore, structural information on PHOX2B is an important target for obtaining clues to elucidate the insurgence of the alanine expansion-related syndrome and also for defining a viable therapy. Here we report by NMR spectroscopy the structural characterization of the homeodomain (HD) of PHOX2B and HD + C-terminus PHOX2B protein, free and in the presence of the target DNA. The obtained structural data are then exploited to obtain a structural model of the PHOX2B-DNA interaction. In addition, the variant +7Ala, responsible for one of the most frequent forms of the syndrome, was analysed, showing different conformational proprieties in solution and a strong propensity to aggregation. Our data suggest that the elongated poly-alanine tract would be related to disease onset through a loss-of-function mechanism. Overall, this study paves the way for the future rational design of therapeutic drugs, suggesting as a possible therapeutic route the use of specific anti-aggregating molecules capable of preventing variant aggregation and possibly restoring the DNA-binding activity of PHOX2B.

15.
JAMA Oncol ; 10(6): 793-798, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38662396

RESUMEN

Importance: Data on oncological outcomes after omission of axillary lymph node dissection (ALND) in patients with breast cancer that downstages from node positive to negative with neoadjuvant chemotherapy are sparse. Additionally, the best axillary surgical staging technique in this scenario is unknown. Objective: To investigate oncological outcomes after sentinel lymph node biopsy (SLNB) with dual-tracer mapping or targeted axillary dissection (TAD), which combines SLNB with localization and retrieval of the clipped lymph node. Design, Setting, and Participants: In this multicenter retrospective cohort study that was conducted at 25 centers in 11 countries, 1144 patients with consecutive stage II to III biopsy-proven node-positive breast cancer were included between April 2013 and December 2020. The cumulative incidence rates of axillary, locoregional, and any invasive (locoregional or distant) recurrence were determined by competing risk analysis. Exposure: Omission of ALND after SLNB or TAD. Main Outcomes and Measures: The primary end points were the 3-year and 5-year rates of any axillary recurrence. Secondary end points included locoregional recurrence, any invasive (locoregional and distant) recurrence, and the number of lymph nodes removed. Results: A total of 1144 patients (median [IQR] age, 50 [41-59] years; 78 [6.8%] Asian, 105 [9.2%] Black, 102 [8.9%] Hispanic, and 816 [71.0%] White individuals; 666 SLNB [58.2%] and 478 TAD [41.8%]) were included. A total of 1060 patients (93%) had N1 disease, 619 (54%) had ERBB2 (formerly HER2)-positive illness, and 758 (66%) had a breast pathologic complete response. TAD patients were more likely to receive nodal radiation therapy (85% vs 78%; P = .01). The clipped node was successfully retrieved in 97% of TAD cases and 86% of SLNB cases (without localization). The mean (SD) number of sentinel lymph nodes retrieved was 3 (2) vs 4 (2) (P < .001), and the mean (SD) number of total lymph nodes removed was 3.95 (1.97) vs 4.44 (2.04) (P < .001) in the TAD and SLNB groups, respectively. The 5-year rates of any axillary, locoregional, and any invasive recurrence in the entire cohort were 1.0% (95% CI, 0.49%-2.0%), 2.7% (95% CI, 1.6%-4.1%), and 10% (95% CI, 8.3%-13%), respectively. The 3-year cumulative incidence of axillary recurrence did not differ between TAD and SLNB (0.5% vs 0.8%; P = .55). Conclusions and Relevance: The results of this cohort study showed that axillary recurrence was rare in this setting and was not significantly lower after TAD vs SLNB. These results support omission of ALND in this population.


Asunto(s)
Axila , Neoplasias de la Mama , Escisión del Ganglio Linfático , Terapia Neoadyuvante , Estadificación de Neoplasias , Humanos , Femenino , Persona de Mediana Edad , Neoplasias de la Mama/patología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/terapia , Neoplasias de la Mama/cirugía , Estudios Retrospectivos , Adulto , Biopsia del Ganglio Linfático Centinela , Metástasis Linfática , Recurrencia Local de Neoplasia , Anciano , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía
16.
Neurobiol Dis ; 50: 187-200, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23103552

RESUMEN

The PHOX2B transcription factor plays a crucial role in autonomic nervous system development. In humans, heterozygous mutations of the PHOX2B gene lead to congenital central hypoventilation syndrome (CCHS), a rare disorder characterized by a broad variety of symptoms of autonomic nervous system dysfunction including inadequate control of breathing. The vast majority of patients with CCHS are heterozygous for a polyalanine repeat expansion mutation involving a polyalanine tract of twenty residues in the C-terminus of PHOX2B. Although several lines of evidence support a dominant-negative mechanism for PHOX2B mutations in CCHS, the molecular effects of PHOX2B mutant proteins on the transcriptional activity of the wild-type protein have not yet been elucidated. As one of the targets of PHOX2B is the PHOX2B gene itself, we tested the transcriptional activity of wild-type and mutant proteins on the PHOX2B gene promoter, and found that the transactivation ability of proteins with polyalanine expansions decreased as a function of the length of the expansion, whereas DNA binding was severely affected only in the case of the mutant with the longest polyalanine tract (+13 alanine). Co-transfection experiments using equimolar amounts of PHOX2B wild-type and mutant proteins in order to simulate a heterozygous state in vitro and four different PHOX2B target gene regulatory regions (PHOX2B, PHOX2A, DBH, TLX2) clearly showed that the polyalanine expanded proteins alter the transcriptional activity of wild-type protein in a promoter-specific manner, without any clear correlation with the length of the expansion. Moreover, although reduced transactivation may be caused by retention of the wild-type protein in the cytoplasm or in nuclear aggregates, this mechanism can only be partially responsible for the pathogenesis of CCHS because of the reduction in cytoplasmic and nuclear accumulation when the +13 alanine mutant is co-expressed with wild-type protein, and the fact that the shortest polyalanine expansions do not form visible cytoplasmic aggregates. Deletion of the C-terminal of PHOX2B leads to a protein that correctly localizes in the nucleus but impairs PHOX2B wild-type transcriptional activity, thus suggesting that protein mislocalization is not the only mechanism leading to CCHS. The results of this study provide novel in vitro experimental evidence of a transcriptional dominant-negative effect of PHOX2B polyalanine mutant proteins on wild-type protein on two different PHOX2B target genes.


Asunto(s)
Expansión de las Repeticiones de ADN/genética , Proteínas de Homeodominio/genética , Hipoventilación/congénito , Apnea Central del Sueño/genética , Factores de Transcripción/genética , Activación Transcripcional/genética , Western Blotting , Ensayo de Cambio de Movilidad Electroforética , Técnica del Anticuerpo Fluorescente , Células HeLa , Humanos , Hipoventilación/genética , Mutación , Péptidos , Regiones Promotoras Genéticas/genética , Transcripción Genética , Transfección
17.
Cancer Cell ; 41(3): 602-619.e11, 2023 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-36868226

RESUMEN

Tumor cells promote the recruitment of immunosuppressive neutrophils, a subset of myeloid cells driving immune suppression, tumor proliferation, and treatment resistance. Physiologically, neutrophils are known to have a short half-life. Here, we report the identification of a subset of neutrophils that have upregulated expression of cellular senescence markers and persist in the tumor microenvironment. Senescent-like neutrophils express the triggering receptor expressed on myeloid cells 2 (TREM2) and are more immunosuppressive and tumor-promoting than canonical immunosuppressive neutrophils. Genetic and pharmacological elimination of senescent-like neutrophils decreases tumor progression in different mouse models of prostate cancer. Mechanistically, we have found that apolipoprotein E (APOE) secreted by prostate tumor cells binds TREM2 on neutrophils, promoting their senescence. APOE and TREM2 expression increases in prostate cancers and correlates with poor prognosis. Collectively, these results reveal an alternative mechanism of tumor immune evasion and support the development of immune senolytics targeting senescent-like neutrophils for cancer therapy.


Asunto(s)
Apolipoproteínas E , Neoplasias de la Próstata , Animales , Humanos , Masculino , Ratones , Apolipoproteínas E/metabolismo , Senescencia Celular/genética , Glicoproteínas de Membrana/genética , Células Mieloides/metabolismo , Neoplasias de la Próstata/metabolismo , Receptores Inmunológicos/metabolismo , Microambiente Tumoral
18.
Neurobiol Dis ; 45(1): 508-18, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21964250

RESUMEN

Heterozygous in frame duplications of the PHOX2B gene, leading to polyalanine (polyAla) expansions ranging from +5 to +13 residues of a 20-alanine stretch, have been identified in the vast majority of patients affected with Congenital Central Hypoventilation Syndrome (CCHS), a rare neurocristopathy characterized by absence of adequate autonomic control of respiration with decreased sensitivity to hypoxia and hypercapnia. Ventilatory supports such as tracheostomy, nasal mask or diaphragm pacing represent the only options available for affected. We have already shown that the severity of the CCHS phenotype correlates with the length of polyAla expansions, ultimately leading to formation of toxic intracytoplasmic aggregates and impaired PHOX2B mediated transactivation of target gene promoters, such as DBH. At present, there is no specific treatment to reduce cell aggregates and to ameliorate patients' respiration. In this work, we have undertaken in vitro analyses aimed at assessing the effects of molecules on the cellular response to polyAla PHOX2B aggregates. In particular, we tested 17-AAG, ibuprofen, 4-PBA, curcumin, trehalose, congo red and chrysamine G for their ability to i) recover the nuclear localisation of polyAla expanded PHOX2B, ii) rescue of PHOX2B mediated transactivation of the DBH promoter, and iii) clearance of PHOX2B (+13 Ala) aggregates. Our data have suggested that 17-AAG and curcumin are effective in vitro in both rescuing the nuclear localization and transactivation activity of PHOX2B carrying the largest expansion of polyAla and promoting the clearance of aggregates of these mutant proteins inducing molecular mechanisms such as ubiquitin-proteasome (UPS), autophagy and heat shock protein (HSP) systems.


Asunto(s)
Apoptosis/efectos de los fármacos , Proteínas de Homeodominio/genética , Hipoventilación/congénito , Péptidos/genética , Apnea Central del Sueño/genética , Factores de Transcripción/genética , Animales , Benzoatos/farmacología , Benzoquinonas/farmacología , Compuestos de Bifenilo/farmacología , Células COS , Células Cultivadas , Chlorocebus aethiops , Rojo Congo/farmacología , Curcumina/farmacología , Células HeLa , Proteínas de Homeodominio/metabolismo , Humanos , Hipoventilación/genética , Hipoventilación/metabolismo , Ibuprofeno/farmacología , Lactamas Macrocíclicas/farmacología , Péptidos/metabolismo , Regiones Promotoras Genéticas/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/genética , Apnea Central del Sueño/metabolismo , Factores de Transcripción/metabolismo , Trehalosa/farmacología
19.
Stem Cell Res ; 61: 102781, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35421844

RESUMEN

Congenital Central Hypoventilation Syndrome (CCHS) is a rare disorder of the autonomic nervous system (ANS), characterized by inadequate control of autonomic ventilation and global autonomic dysfunction. Heterozygous polyalanine repeat expansion mutations in exon 3 of the transcription factor Paired-like homeobox 2B (PHOX2B) gene occur in 90% of CCHS cases. In this study, we describe the generation and characterization of two human induced pluripotent stem cell (hiPSC) lines from female CCHS patients carrying a heterozygous + 5 alanine expansion mutation. The generated iPSC lines show a normal karyotype, express pluripotency markers and are able to differentiate into the three germ layers.


Asunto(s)
Células Madre Pluripotentes Inducidas , Femenino , Proteínas de Homeodominio/genética , Humanos , Hipoventilación/congénito , Mutación/genética , Péptidos , Apnea Central del Sueño , Factores de Transcripción/genética
20.
Eur J Surg Oncol ; 47(4): 796-803, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33097334

RESUMEN

INTRODUCTION: Risk of breast cancer increases with age and very few data are available in patients older than 89. METHODS: A retrospective analysis on patients aged 89 and older treated between 2008 and 2019 at our certified breast center. The aim was to analyze clinical characteristics, decision-making, treatment, outcomes and open questions regarding this subpopulation for which there is a lack of guidelines. RESULTS: 58 patients included. Tumor characteristics were analyzed, 85% patients underwent surgery of which 44% had a mastectomy. The median follow-up and overall survival were 20 and 76 months, respectively.The median survival of metastatic and non-metastatic patients were 14 and 50 months, respectively. Most patients did not receive any adjuvant treatment and among these 14% had a relapse. CONCLUSIONS: Elderly patients should not be under or over-treated because of their age; they represent a large heterogeneous group deserving a sub-stratification for a better tailored treatment.


Asunto(s)
Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Carcinoma in Situ/terapia , Carcinoma Ductal de Mama/terapia , Carcinoma Lobular/terapia , Recurrencia Local de Neoplasia/patología , Anciano de 80 o más Años , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama Masculina/diagnóstico , Neoplasias de la Mama Masculina/patología , Neoplasias de la Mama Masculina/cirugía , Carcinoma in Situ/diagnóstico , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patología , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/secundario , Carcinoma Lobular/diagnóstico , Carcinoma Lobular/metabolismo , Carcinoma Lobular/secundario , Quimioterapia Adyuvante , Toma de Decisiones Clínicas , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Mastectomía , Clasificación del Tumor , Invasividad Neoplásica , Metástasis de la Neoplasia , Estadificación de Neoplasias , Radioterapia Adyuvante , Receptor ErbB-2/metabolismo , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo , Estudios Retrospectivos , Tasa de Supervivencia , Neoplasias de la Mama Triple Negativas/diagnóstico , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/terapia
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