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Enhanced expression of methyltransferase-like 3 (METTL3) promotes the m6A modification of specific mRNAs, contributing to breast tumorigenesis. While the mRNA substrates targeted by METTL3 are well characterized, the factors dictating the selection of these specific mRNA remain elusive. This study aimed to examine the regulatory role of the transcription factor STAT5B in METTL3-induced m6A modification. METTL3 specifically interacts with STAT5B in response to mitogenic stimulation by epidermal growth factor (EGF). Chromatin immunoprecipitation and CRISPR/Cas9 mutagenesis showed that STAT5B recruits METTL3 to gene promoters like CCND1, where METTL3 interacts with RPB1, dependent on CDK9-mediated RPB1 (Ser2) phosphorylation during transcription elongation. Inhibition and depletion of either STAT5B or CDK9 prevented the EGF-induced m6A modification of CCND1. The translation efficiency of CCND1 was increased following m6A modification, thereby increasing cell proliferation. STAT5B facilitated METTL3-induced tumor formation by increasing CCND1 expression in an orthotopic mouse model. In clinical context, a positive correlation was observed between p-STAT5B and METTL3 expression in high-grade breast tumors. This study elucidates a novel mechanism that underlies the specificity of m6A modification in breast cancer cells, thereby underscoring its potential therapeutic value.
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Neoplasias de la Mama , Ciclina D1 , Metiltransferasas , ARN Mensajero , Factor de Transcripción STAT5 , Humanos , Factor de Transcripción STAT5/metabolismo , Factor de Transcripción STAT5/genética , Femenino , Metiltransferasas/genética , Metiltransferasas/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/metabolismo , Animales , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Ratones , Regulación Neoplásica de la Expresión Génica , Proliferación Celular , Quinasa 9 Dependiente de la Ciclina/metabolismo , Quinasa 9 Dependiente de la Ciclina/genética , Carcinogénesis/genética , Línea Celular Tumoral , Adenosina/análogos & derivados , Adenosina/metabolismo , Fosforilación , Regiones Promotoras Genéticas , Factor de Crecimiento Epidérmico/metabolismo , Factor de Crecimiento Epidérmico/genéticaRESUMEN
Background: T-cell leukemia originating from large granular lymphocytes (T-LGL leukemia) is a rare lymphoid neoplasia characterized by clonal proliferation of large granular T lymphocytes expressing αß or γδ T-cell receptor (TCR) on the cell membrane. γδT-LGL leukemia, accounting for approximately 17% of all T-LGL leukemia cases, is associated with autoimmune diseases. However, the features of γδT-LGL leukemia in patients with rheumatologic diseases are still insufficiently characterized. Methods: In this retrospective study, 15 patients with rheumatologic disease-associated γδT-LGL leukemia were included. The patients were obtained from a single center from 2008 to 2023. Data related to clinical characteristics and rheumatologic diagnoses were collected. Immunophenotype evaluations as well as T-lymphocyte clonality (based on TCR-γ, TCR-ß, and TCR-δ gene rearrangements), and signal transducer and activator of transcription (STAT) three and STAT5B mutation analyses (by next-generation sequencing) were performed on blood, bone marrow, and spleen samples. Results: All but one patient had rheumatoid arthritis (RA). In 36% of patients, manifestations of γδT-LGL leukemia were present before or concurrently with clinical manifestations of RA. Splenomegaly was observed in 60% of patients and neutropenia (<1.5 × 109/L) was detected in 93% of cases. CD4-/CD8- and CD4-/CD8+ subtypes were detected in seven cases each. Mutations in STAT3 were detected in 80% of patients; however, STAT5B mutations were not detected. Evaluations of T-cell clonality and variant allele frequencies at STAT3 in the blood, bone marrow, and spleen tissue revealed an unusual variant of CD4-/CD8- γδT-LGL leukemia with predominant involvement of the spleen, involvement of the bone marrow to a less extent, and no tumor cells in peripheral blood. Conclusion: The mechanism by which γδT-LGL leukemia may induce the development of RA in some patients requires further investigation. Cases of RA-associated γδT-LGL leukemia with neutropenia and splenomegaly but no detectable tumor-associated lymphocytes in peripheral blood (the so-called splenic variant of T-LGL leukemia) are difficult to diagnose and may be misdiagnosed as Felty syndrome or hepatosplenic T-cell lymphoma.
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Monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL), also known as type II enteropathy-associated T-cell lymphoma, is a rare malignant lymphoma of the extranodal lymphoid tissue derived from interepithelial T lymphocytes. MEITL is a primary intestinal T-cell lymphoma with a challenging diagnosis and aggressive progression, and it can invade other extraintestinal sites. In this study, we report four patients diagnosed with MEITL. All patients presented with abdominal pain, and one patient was admitted because of acute intestinal perforation. Two patients presented with unformed defecation and diarrhea. All patients carried the immunophenotypes CD3, CD7, CD8, CD20, and CD56, and the Ki-67 index ranged 60% to 90%. Three cases were analyzed using next-generation sequencing. One case displayed possibly relevant alterations of CREBBP, NOTCH2, SETD2, and STAT5B, and another case exhibited definite alteration of NOTCH1, possibly relevant alterations of CCND1 and DNMT3A, and potentially relevant alterations of HISTH3B, IGLL5, KMT2C, and KRAS. Different chemotherapy regimens were used, but the prognosis was poor. Hence, we illustrated that because of its low incidence, challenging diagnosis, and difficult treatment, further therapeutic improvements are urgently warranted.
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Linfoma de Células T Asociado a Enteropatía , Humanos , Linfoma de Células T Asociado a Enteropatía/diagnóstico , Linfoma de Células T Asociado a Enteropatía/tratamiento farmacológico , Linfoma de Células T Asociado a Enteropatía/genética , Linfoma de Células T Asociado a Enteropatía/inmunología , Inmunofenotipificación , Neoplasias Intestinales/diagnóstico , Neoplasias Intestinales/tratamiento farmacológico , Neoplasias Intestinales/genética , Neoplasias Intestinales/inmunología , PronósticoRESUMEN
Canine gastrointestinal lymphoma is known to be of T-cell origin in most cases, but the molecular biological aberrations have not been clarified. In human intestinal T-cell lymphoma, the mutations in the genes associated with Janus kinase/signal transducer and activator of transcription (JAK-STAT) pathway have been frequently observed. In this study, the gene mutations were investigated in 31 dogs with large cell gastrointestinal lymphoma (LCGIL) by focusing on the genes involved in JAK-STAT pathway. Next-generation sequencing analysis to examine the mutations in STAT3, STAT5B, and JAK1 genes throughout the exon regions revealed the mutations in STAT3 gene in two dogs and JAK1 gene in one dog. In conclusion, this study could not indicate the associations of gene mutations in JAK-STAT pathway with LCGIL in most canine cases.
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Janus kinase (JAK) and signal transducer and activator of transcription (STAT) signaling affect social aggregation, mood and psychiatric disorders, nociceptive and depressive behaviors. Olfactory dysfunction is one of the distinct symptoms of these behaviors, but function and mechanism of JAK and STAT in modulating olfaction remain largely unknown. Migratory locusts show olfactory preference for their own volatiles. We thus use this animal model to explore functions and mechanisms of JAK and STAT5B in mediating olfaction response to their own volatiles. Tissue distribution study shows that JAK and STAT5B express in antennae and brains, especially in antennal lobes and mushroom bodies in locust brains, and knockdown of these two genes by RNA interference (RNAi) in antennae and brains results in the loss of olfactory preference for locust volatiles, including chemical odorants indole and ß-ionone. RNA-seq analysis reveals that JAK and STAT5B RNAi knockdown downregulates a functional class of transcripts in nucleoprotein complex, including heterogeneous nuclear ribonucleoprotein C (hnRNPC) and small nuclear ribonucleoprotein polypeptide F (SNRPF). HnRNPC and SNRPF mRNAs and proteins are also expressed in antennae and brains, and RNAi knockdown of these two genes reduces the percentage of locusts preferring volatiles, including chemical odorants indole and ß-ionone. Furthermore, RNAi knockdown of dopamine receptor 1 (DopR1) results in the decrease of JAK mRNA level in antennae, and JAK/STAT5B, hnRNPC and SNRPF are required for dopamine receptor 1 (DopR1) to modulate olfactory preference for their own volatiles. This study confirms that JAK/STAT5B signaling modulates olfaction by affecting expression levels of hnRNPC and SNRPF, and this pathway is also required for DopR1 to modulate olfactory preference for their own volatiles. These findings highlight novel roles of JAK and STAT5B in modulating olfactory preference. This study provides novel insights into functional links among JAK/STAT5B signaling, RNA binding proteins and DopR1 underlying the modulation of olfactory behaviors.
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Proteínas de Insectos , Quinasas Janus , Animales , Quinasas Janus/metabolismo , Quinasas Janus/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Factor de Transcripción STAT5/metabolismo , Factor de Transcripción STAT5/genética , Olfato , Antenas de Artrópodos/metabolismo , Locusta migratoria/metabolismo , Locusta migratoria/genética , Encéfalo/metabolismo , Transducción de Señal , Interferencia de ARNRESUMEN
Objective: The purpose of this study was to analyze the mechanism by which STAT5B inhibits ferroptosis in mantle cell lymphoma (MCL) by promoting DCAF13 transcriptional regulation of p53/xCT pathway. Methods: The correlations between STAT5B, DCAF13 and ferroptosis in MCL were analyzed using Gene Expression Profiling Interactive Analysis (GEPIA, http://gepia.cancer-pku.cn/index.html). The expression levels and pairwise correlations of STAT5B, DCAF13, p53 and xCT in MCL patients were detected, respectively. STAT5B was silenced to confirm their criticality in MCL ferroptosis. the effects of blocking necrosis, apoptosis and ferroptosis on the anti-MCL effects of STAT5B were examined. Cells with STAT5B overexpression and/or DCAF13 silencing were constructed to confirm the involvement of DCAF13 in the STAT5B-regulated p53/xCT pathway. The regulation of p53 ubiquitination was confirmed by DCAF13 overexpression and MG132. The effects of silencing DCAF13 and MG132 on STAT5B overexpression on MCL was clarified by a tumor-bearing nude mouse model. Results: DCAF13 was overexpressed in MCL and positively correlated with STAT5B, negatively correlated with p53, and positively correlated with xCT. Inhibition of ferroptosis alleviated the inhibitory effects of siSTAT5B on MCL, while inhibition of necrosis and apoptosis had few effects. Silencing of DCAF13 led to the blocking of STAT5B regulation of p53/xCT and ferroptosis. The changes in DCAF13 and the addition of MG132 did not have statistically significant effects on p53 mRNA. Elevation of DCAF13 resulted in downregulation of p53 protein levels, and this inhibition was reversed by MG132. In animal models, the promotion of MCL and the inhibition of ferroptosis by STAT5B. Silencing of DCAF13 blocked STAT5B inhibition of p53 and induction of xCT, GPX4, and GSH. Conclusion: STAT5B suppresses ferroptosis by promoting DCAF13 transcription to regulate p53/xCT pathway to promote MCL progression.
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γ-Synuclein (SNCG) has various biological functions associated with tumorigenesis. However, the role of SNCG in oral squamous cell carcinoma (OSCC) remains unknown. In this study, we found that SNCG expression is associated with the malignancy of OSCC. We showed that SNCG promotes cell proliferation and inhibits apoptosis in OSCC. Mechanistically, we demonstrated for the first time, that SNCG interacts with ERK1/2 and promotes its phosphorylation leading to activation of the JAK2/STAT5b signaling pathway. Subsequent experiments with STAT5b interference and ERK1/2 inhibitor treatment reversed the effects of SNCG on OSCC cell proliferation, apoptosis and cell cycle progression. Our findings suggest that SNCG functions as an oncogene in OSCC by targeting the JAK2/STAT5b axis and thus may be a potential new prognostic marker and therapeutic target in OSCC.
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BACKGROUND: Small intestinal monomorphic-epitheliotropic intestinal T-cell lymphoma (MEITL) is a rare aggressive T-cell lymphoma originating in the gastrointestinal tract. This study aimed to investigate the clinicopathological features, immunophenotypes, and molecular genetic changes of MEITL. METHODS: The clinicopathological data for three patients with surgically resected MEITL of the small intestine were collected. Next, immunohistochemical labeling, Epstein-Barr virus (EBV) in situ hybridization, assessment of clonal rearrangement of T-cell receptor (TCR) genes, and next-generation sequencing (NGS) were performed. RESULTS: Of the three patients, two were male and one was female, with ages of 61, 67, and 73 years, respectively. Clinical manifestations were predominantly abdominal pain and distension. Histopathology revealed infiltrative growth of small-to-medium-sized lymphocytes with a consistent morphology between the intestinal walls, accompanied by an obvious pro-epithelial phenomenon. The expression of CD3, CD8, CD43, CD56, TIA-1, CD103, H3K36me3, and Bcl-2 was detected, and the Ki-67 proliferation index ranged from 50% to 80%. All three patients tested negative for EBER. However, monoclonal rearrangement of the TCR gene was detected in them. NGS testing showed a JAK3 mutation in all three cases. Further, STAT5B, SETD2, and TP53 mutations were each observed in two cases, and a BCOR mutation was found in one case. All patients were treated with chemotherapy after surgery. Two patients died 7 and 15 month post-operation, and one patient survived for 5 months of follow-up. CONCLUSIONS: Our findings demonstrate that mutations in JAK3 and STAT5B of the JAK/STAT pathway and inactivation of the oncogene SETD2 markedly contribute to the lymphomagenesis of MEITL.
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Linfoma de Células T Asociado a Enteropatía , Infecciones por Virus de Epstein-Barr , Linfoma de Células T , Humanos , Masculino , Femenino , Infecciones por Virus de Epstein-Barr/complicaciones , Infecciones por Virus de Epstein-Barr/genética , Quinasas Janus , Transducción de Señal , Herpesvirus Humano 4/genética , Factores de Transcripción STAT , Linfoma de Células T Asociado a Enteropatía/genética , Linfoma de Células T Asociado a Enteropatía/complicaciones , Linfoma de Células T/genética , Linfoma de Células T/complicaciones , Linfoma de Células T/patología , Intestino Delgado/patología , Mutación/genética , Biología MolecularRESUMEN
Monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) is a rare and aggressive T-cell neoplasm associated with poor survival. We report a case of MEITL that presented as an ulcerated mass in the jejunum with perforation. Microscopic examination showed that the neoplasm involved the full thickness of the intestinal wall, extended into the mesentery, and was composed of monomorphic, small to medium-size cells. Immunohistochemical analysis showed that the neoplastic cells were positive for T-cell receptor (TCR) delta, CD3, CD7, CD8 (small subset), BCL-2 and TIA-1, and negative for TCR beta, CD4, CD5, CD10, CD20, CD30, CD34, CD56, CD57, CD99, ALK, cyclin D1, granzyme B, MUM1/IRF4, and TdT. The Ki-67 proliferation index was approximately 50 %. In situ hybridization for Epstein-Barr virus-encoded RNA (EBER ISH) was negative. Next-generation sequencing (NGS) analysis showed mutations involving SETD2 and STAT5B. The patient was treated with aggressive chemotherapy and consolidative autologous stem cell transplant and had clinical remission, but relapsed after about one year. Retreatment led to another one-year interval of clinical remission, but at last follow up the patient has relapsed disease involving the ileum and colon. We also discuss the differential diagnosis of MEITL.
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Inmunofenotipificación , Humanos , Masculino , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/análisis , Diagnóstico Diferencial , Inmunofenotipificación/métodos , Neoplasias Intestinales/diagnóstico , Neoplasias Intestinales/patología , Linfoma de Células T/diagnóstico , Linfoma de Células T/patología , AncianoRESUMEN
Growth hormone (GH) modifies liver gene transcription in a sexually dimorphic manner to meet liver metabolic demands related to sex; thus, GH dysregulation leads to sex-biased hepatic disease. We dissected the steps of the GH regulatory cascade modifying GH-dependent genes involved in metabolism, focusing on the male-predominant genes Lcn13, Asns, and Cyp7b1, and the female-predominant genes Hao2, Pgc1a, Hamp2, Cyp2a4, and Cyp2b9. We explored mRNA expression in 2 settings: (i) intact liver GH receptor (GHR) but altered GH and insulin-like growth factor 1 (IGF1) levels (NeuroDrd2KO, HiGH, aHepIGF1kd, and STAT5bCA mouse lines); and (ii) liver loss of GHR, with or without STAT5b reconstitution (aHepGHRkd, and aHepGHRkd + STAT5bCA). Lcn13 was downregulated in males in most models, while Asns and Cyp7b1 were decreased in males by low GH levels or action, or constant GH levels, but unexpectedly upregulated in both sexes by the loss of liver Igf1 or constitutive Stat5b expression. Hao, Cyp2a4, and Cyp2b9 were generally decreased in female mice with low GH levels or action (NeuroDrd2KO and/or aHepGHRkd mice) and increased in HiGH females, while in contrast, Pgc1a was increased in female NeuroDrd2KO but decreased in STAT5bCA and aHepIGF1kd females. Bioinformatic analysis of RNAseq from aHepGHRkd livers stressed the greater impact of GHR loss on wide gene expression in males and highlighted that GH modifies almost completely different gene signatures in each sex. Concordantly, we show that altering different steps of the GH cascade in the liver modified liver expression of Lcn13, Asns, Cyp7b1, Hao2, Hamp2, Pgc1a, Cyp2a4, and Cyp2b9 in a sex- and gene-specific manner.
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INTRODUCTION: Patients with homozygous recessive mutations in STAT5B have severe progressive postnatal growth failure and insulin-like growth factor-I (IGF-I) deficiency associated with immunodeficiency and increased risk of autoimmune and pulmonary conditions. This report describes the efficacy and safety of recombinant human IGF-1 (rhIGF-1) in treating severe growth failure due to STAT5B deficiency. CASE PRESENTATION: Three siblings (P1, 4.4 year-old female; P2, 2.3 year-old male; and P3, 7 month-old female) with severe short stature (height SDS [HtSDS] -6.5, -4.9, -5.3, respectively) were referred to the Center for Growth Disorders at Cincinnati Children's Hospital Medical Center. All three had a homozygous mutation (p.Trp631*) in STAT5B. Baseline IGF-I was 14.7, 14.1, and 10.8 ng/mL, respectively (all < -2.5 SDS for age and sex), and IGFBP-3 was 796, 603, and 475 ng/mL, respectively (all < -3 SDS for age and sex). The siblings were started on rhIGF-1 at 40 µg/kg/dose twice daily subcutaneously (SQ), gradually increased to 110-120 µg/kg/dose SQ twice daily as tolerated. HtSDS and height velocity (HV) were monitored over time. RESULTS: Six years of growth data was utilized to quantify growth response in the two older siblings and 5 years of data in the youngest. Pre-treatment HVs were, respectively, 3.0 (P1), 3.0 (P2), and 5.2 (P3) cm/year. With rhIGF-1 therapy, HVs increased to 5.2-6.0, 4.8-7.1, and 5.5-7.4 cm/year, respectively, in the first 3 years of treatment, before they decreased to 4.7, 3.8, and 4.3 cm/year, respectively, at a COVID-19 pandemic delayed follow-up visit and with decreased treatment adherence. ΔHtSDS for P1 and P2 was +2.21 and +0.93, respectively, over 6 years, but -0.62 for P3 after 5 years and in the setting of severe local lipohypertrophy and suboptimal weight gain. P3 also experienced hypoglycemia that limited our ability to maintain target rhIGF-1 dosing. CONCLUSION: The response to rhIGF-1 therapy is less than observed with rhIGF-1 therapy for patients previously described with severe primary IGF-I deficiency, including patients with documented defects in the growth hormone receptor, but may still provide patients with STAT5B deficiency with an opportunity to prevent worsening growth failure.
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Insuficiencia de Crecimiento , Trastornos del Crecimiento , Factor I del Crecimiento Similar a la Insulina , Péptidos Similares a la Insulina , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Factor I del Crecimiento Similar a la Insulina/deficiencia , Factor I del Crecimiento Similar a la Insulina/uso terapéutico , Proteínas Recombinantes/uso terapéutico , Hermanos , Factor de Transcripción STAT5/genética , SíndromeRESUMEN
Acute promyelocytic leukemia (APL) with typically PML::RARA fusion gene caused by t (15;17) (q22; q12) was distinguished from other types of acute myeloid leukemia. In a subset of patients with APL, t (15;17) (q22;q21) and PML::RARA fusion cannot be detected. In this report, we identified the coexistence of STAT3::RARA and RARA::STAT5b fusions for the first time in a variant APL patient lacking t (15;17)(q22;q21)/PML::RARA fusion. Then, this patient was resistant to all-trans retinoic acid combined arsenic trioxide chemotherapy. Accurate detection of RARA gene partners is crucial for variant APL, and effective therapeutic regime is urgently needed.
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Leucemia Promielocítica Aguda , Humanos , Leucemia Promielocítica Aguda/tratamiento farmacológico , Leucemia Promielocítica Aguda/genética , Tretinoina , Factor de Transcripción STAT3/genéticaRESUMEN
Sex differences in plasma growth hormone (GH) profiles, pulsatile in males and persistent in females, regulate sex differences in hepatic STAT5 activation linked to sex differences in gene expression and liver disease susceptibility, but little is understood about the fundamental underlying, GH pattern-dependent regulatory mechanisms. Here, DNase-I hypersensitivity site (DHS) analysis of liver chromatin accessibility in a cohort of 18 individual male mice established that the endogenous male rhythm of plasma GH pulse-stimulated liver STAT5 activation induces dynamic, repeated cycles of chromatin opening and closing at several thousand liver DHS and comprises a novel mechanism conferring male bias to liver chromatin accessibility. Strikingly, a single physiological replacement dose of GH given to hypophysectomized male mice restored, within 30 min, liver STAT5 activity and chromatin accessibility at 83% of the dynamic, pituitary hormone-dependent male-biased DHS. Sex-dependent transcription factor binding patterns and chromatin state analysis identified key genomic and epigenetic features distinguishing this dynamic, STAT5-driven mechanism of male-biased chromatin opening from a second GH-dependent mechanism operative at static male-biased DHS, which are constitutively open in male liver. Dynamic but not static male-biased DHS adopt a bivalent-like epigenetic state in female liver, as do static female-biased DHS in male liver, albeit using distinct repressive histone marks in each sex, namely, H3K9me3 at male-biased DHS in female liver and H3K27me3 at female-biased DHS in male liver. Moreover, sex-biased H3K36me3 marks are uniquely enriched at static sex-biased DHS, which may serve to keep these sex-dependent hepatocyte enhancers free of H3K27me3 repressive marks and thus constitutively open. Pulsatile chromatin opening stimulated by endogenous, physiological hormone pulses is thus one of two distinct GH-determined mechanisms for establishing widespread sex differences in hepatic chromatin accessibility and epigenetic regulation, both closely linked to sex-biased gene transcription and the sexual dimorphism of liver function.
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Cromatina , Hormona del Crecimiento , Humanos , Femenino , Ratones , Masculino , Animales , Hormona del Crecimiento/metabolismo , Cromatina/metabolismo , Factor de Transcripción STAT5/genética , Factor de Transcripción STAT5/metabolismo , Histonas/metabolismo , Epigénesis Genética , Hígado/metabolismoRESUMEN
Per- and poly-fluoroalkyl substances (PFAS) are a large class of fluorinated carbon chains that include legacy PFAS, such as perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorohexane sulfonate (PFHxS). These compounds induce adverse health effects, including hepatotoxicity. Potential alternatives to the legacy PFAS (HFPO-DA (GenX), HFPO4, HFPO-TA, F-53B, 6:2 FTSA, and 6:2 FTCA), as well as a byproduct of PFAS manufacturing (Nafion BP2), are increasingly being found in the environment. The potential hazards of these new alternatives are less well known. To better understand the diversity of molecular targets of the PFAS, we performed a comparative toxicogenomics analysis of the gene expression changes in the livers of mice exposed to these PFAS, and compared these to five activators of PPARα, a common target of many PFAS. Using hierarchical clustering, pathway analysis, and predictive biomarkers, we found that most of the alternative PFAS modulate molecular targets that overlap with legacy PFAS. Only three of the 11 PFAS tested did not appreciably activate PPARα (Nafion BP2, 6:2 FTSA, and 6:2 FTCA). Predictive biomarkers showed that most PFAS (PFHxS, PFOA, PFOS, PFNA, HFPO-TA, F-53B, HFPO4, Nafion BP2) activated CAR. PFNA, PFHxS, PFOA, PFOS, HFPO4, HFPO-TA, F-53B, Nafion BP2, and 6:2 FTSA suppressed STAT5b, activated NRF2, and activated SREBP. There was no apparent relationship between the length of the carbon chain, type of head group, or number of ether linkages and the transcriptomic changes. This work highlights the similarities in molecular targets between the legacy and alternative PFAS.
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Introduction: Inhibition of STAT5 was recently reported to reduce murine atherosclerosis. However, the role of STAT5 isoforms, and more in particular STAT5A in macrophages in the context of human atherosclerosis remains unknown. Methods and results: Here, we demonstrate reciprocal expression regulation of STAT5A and STAT5B in human atherosclerotic lesions. The former was highly upregulated in ruptured over stable plaque and correlated with macrophage presence, a finding that was corroborated by the high chromosomal accessibility of STAT5A but not B gene in plaque macrophages. Phosphorylated STAT5 correlated with macrophages confirming its activation status. As macrophage STAT5 is activated by GM-CSF, we studied the effects of its silencing in GM-CSF differentiated human macrophages. STAT5A knockdown blunted the immune response, phagocytosis, cholesterol metabolism, and augmented apoptosis terms on transcriptional levels. These changes could partially be confirmed at functional level, with significant increases in apoptosis and decreases in lipid uptake and IL-6, IL-8, and TNFa cytokine secretion after STAT5A knockdown. Finally, inhibition of general and isoform A specific STAT5 significantly reduced the secretion of TNFa, IL-8 and IL-10 in ex vivo tissue slices of advanced human atherosclerotic plaques. Discussion: In summary, we identify STAT5A as an important determinant of macrophage functions and inflammation in the context of atherosclerosis and show its promise as therapeutic target in human atherosclerotic plaque inflammation.
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Aterosclerosis , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Humanos , Animales , Ratones , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Transactivadores/genética , Factor de Transcripción STAT5/metabolismo , Interleucina-8/metabolismo , Transducción de Señal , Macrófagos , Aterosclerosis/metabolismo , Inflamación/metabolismo , Proteínas Supresoras de Tumor/metabolismoRESUMEN
Iron homeostasis is considered a key factor in human metabolism, and abrogation in the system could create adverse effects, including cancer. Moreover, 6-gingerol is a widely used bioactive phenolic compound with anticancer activity, and studies on its exact mechanisms on non-small cell lung cancer (NSCLC) cells are still undergoing. This study aimed to find the mechanism of cell death induction by 6-gingerol in NSCLC cells. Western blotting, real-time polymerase chain reaction, and flow cytometry were used for molecular signaling studies, and invasion and tumorsphere formation assay were also used with comet assay for cellular processes. Our results show that 6-gingerol inhibited cancer cell proliferation and induced DNA damage response, cell cycle arrest, and apoptosis in NSCLC cells, and cell death induction was found to be the mitochondrial-dependent intrinsic apoptosis pathway. The role of iron homeostasis in the cell death induction of 6-gingerol was also investigated, and iron metabolism played a vital role in the anticancer ability of 6-gingerol by downregulating EGFR/JAK2/STAT5b signaling or upregulating p53 and downregulating PD-L1 expression. Also, 6-gingerol induced miR-34a and miR-200c expression, which may indicate regulation of PD-L1 expression by 6-gingerol. These results suggest that 6-gingerol could be a candidate drug against NSCLC cells and that 6-gingerol could play a vital role in cancer immunotherapy.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , MicroARNs , Humanos , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/genética , Antígeno B7-H1/metabolismo , Línea Celular Tumoral , MicroARNs/genética , HierroRESUMEN
Sex-differences in plasma growth hormone (GH) profiles, pulsatile in males and persistent in females, regulate sex differences in hepatic STAT5 activation linked to sex differences in gene expression and liver disease susceptibility, but little is understood about the fundamental underlying, GH pattern-dependent regulatory mechanisms. Here, DNase hypersensitivity site (DHS) analysis of liver chromatin accessibility in a cohort of 18 individual male mice established that the endogenous male rhythm of plasma GH pulse-stimulated liver STAT5 activation induces dynamic, repeated cycles of chromatin opening and closing at several thousand liver DHS and comprises a novel mechanism conferring male bias to liver chromatin accessibility. Strikingly, a single physiological replacement dose of GH given to hypophysectomized male mice restored, within 30 min, liver STAT5 activity and chromatin accessibility at 83% of the pituitary hormone-dependent dynamic male-biased DHS. Sex-dependent transcription factor binding patterns and chromatin state analysis identified key genomic and epigenetic features distinguishing this dynamic, STAT5-driven mechanism of male-biased chromatin opening from a second GH-dependent mechanism operative at static male-biased DHS, which are constitutively open in male liver. Dynamic but not static male-biased DHS adopt a bivalent-like epigenetic state in female liver, as do static female-biased DHS in male liver, albeit using distinct repressive histone marks in each sex, namely, H3K27me3 at female-biased DHS in male liver, and H3K9me3 at male-biased DHS in female liver. Moreover, sex-biased H3K36me3 marks are uniquely enriched at static sex-biased DHS, which may serve to keep these sex-dependent hepatocyte enhancers free of H3K27me3 repressive marks and thus constitutively open. Pulsatile chromatin opening stimulated by endogenous, physiological hormone pulses is thus one of two distinct GH-determined mechanisms for establishing widespread sex differences in hepatic chromatin accessibility and epigenetic regulation, both closely linked to sex-biased gene transcription and the sexual dimorphism of liver function.
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Fluorescence polarization (FP) assays can be used to identify small-molecule inhibitors that bind to SH2 domain-containing proteins. We have developed FP assays by which to identify inhibitors of the SH2 domains of the two closely-related transcription factors STAT5a and STAT5b. Point mutation of selected amino acids in the putative binding site of the protein is a valuable tool by which to gain insight into the molecular mechanism of binding. In this chapter, we describe the cloning and application of point mutant proteins in order to transfer the binding preference of selected SH2 domain-binding STAT5b inhibitors to STAT5a, with results that highlight the importance of considering a role for residues outside the SH2 domain in contributing to the binding interactions of SH2 domain inhibitors.
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Aminoácidos , Dominios Homologos src , Sitios de Unión , Proteínas Mutantes , Polarización de FluorescenciaRESUMEN
Myxofibrosarcoma is genetically complex without established nonsurgical therapies. In public datasets, PAK1 was recurrently gained with mRNA upregulation. Using myxofibrosarcoma cells, we explored the oncogenic underpinning of PAK1 with genetic manipulation and a pan-PAK inhibitor (PF3758309). Myxofibrosarcoma specimens were analyzed for the levels of PAK1, phospho-PAKT423, CSF2 and microvascular density (MVD) and those of PAK1 gene and mRNA. PAK1-expressing xenografts were assessed for the effects of PF3758309 and CSF2 silencing. Besides pro-proliferative and pro-migrator/pro-invasive attributes, PAK1 strongly enhanced angiogenesis in vitro, which, not phenocopied by PAK2-4, was identified as CSF2-mediated using antibody arrays. PAK1 underwent phosphorylation at tyrosines153,201,285 and threonine423 to facilitate nuclear entry, whereby nuclear PAK1 bound STAT5B to co-transactivate the CSF2 promoter, increasing CSF2 secretion needed for angiogenesis. Angiogenesis driven by PAK1-upregulated CSF2 was negated by CSF2 silencing, anti-CSF2, and PF3758309. Clinically, overexpressed whole-cell phospho-PAKT423, related to PAK1 amplification, was associated with increased grades, stages, and PAK1 mRNA, higher MVD, and CSF2 overexpression. Overexpressed whole-cell phospho-PAKT423 and CSF2 independently portended shorter metastasis-free survival and disease-specific survival, respectively. In vivo, both CSF2 silencing and PF3758309 suppressed PAK1-driven tumor proliferation and angiogenesis. Conclusively, the nuclear entry of overexpressed/activated PAK1 endows myxofibrosarcomas with pro-angiogenic function, highlighting the vulnerable PAK1/STAT5B/CSF2 regulatory axis.
Asunto(s)
Fibrosarcoma , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Factor de Transcripción STAT5 , Quinasas p21 Activadas , Humanos , Línea Celular Tumoral , Quinasas p21 Activadas/genética , Quinasas p21 Activadas/metabolismo , Fosforilación , ARN Mensajero/metabolismo , Factor de Transcripción STAT5/genética , Factor de Transcripción STAT5/metabolismo , Activación Transcripcional , Animales , Fibrosarcoma/genética , Fibrosarcoma/patología , Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismoRESUMEN
BACKGROUND: Plasmacytoma Variant Translocation 1 (LncRNA PVT1) and signal transducer and activator of transcription 5B (STAT5B) play important roles in various cancers, but their interaction in bladder cancer (BC) remains unclear. PURPOSE: We aimed to explore the interaction between lncRNA PVT1 and STAT5B in BC tumorigenesis and find potential drugs for BC. METHODS: The association of the expression of lncRNA PVT1 and STAT5B to the prognosis of BC patients was evaluated via bioinformatic analysis. Loss- and gain-of-function assays were performed to determine the biological functions of lncRNA PVT1 and STAT5B. Quantitative real time polymerase chain reaction, Western blot, immunohistochemistry, and immunofluorescence were used to detect lncRNA PVT1 and STAT5B expression. Fluorescence in situ hybridization, RNA pull-down and RNA immunoprecipitation assays were conducted to determine the regulatory effect of lncRNA PVT1 on STAT5B. The transcriptional effect of STAT5B on lncRNA PVT1 gene was determined using luciferase reporter assay, chromatin immunoprecipitation and DNA-affinity precipitation assays. Connectivity Map analysis was used to screen anticancer drugs. RESULTS: LncRNA PVT1 and STAT5B enhance the expression of each other and promote the malignant phenotypes in BC, including cell viability and invasion. lncRNA PVT1 stabilizes STAT5B by decreasing ubiquitination, enhances STAT5B phosphorylation, and promotes the translocation to the nucleus of STAT5B to trigger further carcinogenesis activities. In the nucleus, STAT5B activates the transcription of lncRNA PVT1 by binding directly to its promoter region, leading to a positive feedback. Tanespimycin effectively abated the oncogenic effect. CONCLUSIONS: We first identified the lncRNA PVT1/STAT5B positive feedback loop for bladder carcinogenesis, and found a potentially effective drug for BC.