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1.
Cancer ; 2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38733613

RESUMO

INTRODUCTION: Cancer risk factors are more common among sexual minority populations (e.g., lesbian, bisexual) than their heterosexual peers, yet little is known about cancer incidence across sexual orientation groups. METHODS: The 1989-2017 data from the Nurses' Health Study II, a longitudinal cohort of female nurses across the United States, were analyzed (N = 101,543). Sexual orientation-related cancer disparities were quantified by comparing any cancer incidence among four sexual minority groups based on self-disclosure-(1) heterosexual with past same-sex attractions/partners/identity; (2) mostly heterosexual; (3) bisexual; and (4) lesbian women-to completely heterosexual women using age-adjusted incidence rate ratios (aIRR) calculated by the Mantel-Haenszel method. Additionally, subanalyses at 21 cancer disease sites (e.g., breast, colon/rectum) were conducted. RESULTS: For all-cancer analyses, there were no statistically significant differences in cancer incidence at the 5% type I error cutoff among sexual minority groups when compared to completely heterosexual women; the aIRR was 1.17 (95% CI,0.99-1.38) among lesbian women and 0.80 (0.58-1.10) among bisexual women. For the site-specific analyses, incidences at multiple sites were significantly higher among lesbian women compared to completely heterosexual women: thyroid cancer (aIRR, 1.87 [1.03-3.41]), basal cell carcinoma (aIRR, 1.85 [1.09-3.14]), and non-Hodgkin lymphoma (aIRR, 2.13 [1.10-4.12]). CONCLUSION: Lesbian women may be disproportionately burdened by cancer relative to their heterosexual peers. Sexual minority populations must be explicitly included in cancer prevention efforts. Comprehensive and standardized sexual orientation data must be systematically collected so nuanced sexual orientation-related cancer disparities can be accurately assessed for both common and rare cancers.

2.
Hum Reprod ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689464

RESUMO

STUDY QUESTION: Does medically assisted reproduction (MAR) use among cisgender women differ among those with same-sex partners or lesbian/bisexual identities compared to peers with different-sex partners or heterosexual identities? SUMMARY ANSWER: Women with same-sex partners or lesbian/bisexual identities are more likely to utilize any MAR but are no more likely to use ART (i.e. IVF, reciprocal IVF, embryo transfer, unspecified ART, ICSI, and gamete or zygote intrafallopian transfer) compared to non-ART MAR (i.e. IUI, ovulation induction, and intravaginal or intracervical insemination) than their different-sex partnered and completely heterosexual peers. WHAT IS KNOWN ALREADY: Sexual minority women (SMW) form families in myriad ways, including through fostering, adoption, genetic, and/or biological routes. Emerging evidence suggests this population increasingly wants to form genetic and/or biological families, yet little is known about their family formation processes and conception needs. STUDY DESIGN, SIZE, DURATION: The Growing Up Today Study is a US-based prospective cohort (n = 27 805). Participants were 9-17 years of age at enrollment (1996 and 2004). Biennial follow-up is ongoing, with data collected through 2021. PARTICIPANTS/MATERIALS, SETTING, METHODS: Cisgender women who met the following criteria were included in this sample: endorsed ever being pregnant; attempted a pregnancy in 2019 or 2021; and endorsed either a male- or female-sex partner OR responded to questions regarding their sexual identity during their conception window. The main outcome was any MAR use including ART (i.e. procedures involving micromanipulation of gametes) and non-ART MAR (i.e. nonmanipulation of gametes). Secondary outcomes included specific MAR procedures, time to conception, and trends across time. We assessed differences in any MAR use using weighted modified Poisson generalized estimating equations. MAIN RESULTS AND THE ROLE OF CHANCE: Among 3519 participants, there were 6935 pregnancies/pregnancy attempts and 19.4% involved MAR. A total of 47 pregnancies or pregnancy attempts were among the same-sex partnered participants, while 91 were among bisexual participants and 37 among lesbian participants. Participants with same-sex, compared to different-sex partners were almost five times as likely to use MAR (risk ratio [95% CI]: 4.78 [4.06, 5.61]). Compared to completely heterosexual participants, there was greater MAR use among lesbian (4.00 [3.10, 5.16]) and bisexual (2.22 [1.60, 3.07]) participants compared to no MAR use; mostly heterosexual participants were also more likely to use ART (1.42 [1.11, 1.82]) compared to non-ART MAR. Among first pregnancies conceived using MAR, conception pathways differed by partnership and sexual identity groups; differences were largest for IUI, intravaginal insemination, and timed intercourse with ovulation induction. From 2002 to 2021, MAR use increased proportionally to total pregnancies/pregnancy attempts; ART use was increasingly common in later years among same-sex partnered and lesbian participants. LIMITATIONS, REASONS FOR CAUTION: Our results are limited by the small number of SMW, the homogenous sample of mostly White, educated participants, the potential misclassification of MAR use when creating conception pathways unique to SMW, and the questionnaire's skip logic, which excluded certain participants from receiving MAR questions. WIDER IMPLICATIONS OF THE FINDINGS: Previous studies on SMW family formation have primarily focused on clinical outcomes from ART procedures and perinatal outcomes by conception method, and have been almost exclusively limited to European, clinical samples that relied on partnership data only. Despite the small sample of SMW within a nonrepresentative study, this is the first study to our knowledge to use a nonclinical sample of cisgender women from across the USA to elucidate family formation pathways by partnership as well as sexual identity, including pathways that may be unique to SMW. This was made possible by our innovative approach to MAR categorization within a large, prospective dataset that collected detailed sexual orientation data. Specifically, lesbian, bisexual, and same-sex partnered participants used both ART and non-ART MAR at similar frequencies compared to heterosexual and different-sex partnered participants. This may signal differential access to conception pathways owing to structural barriers, emerging conception trends as family formation among SMW has increased, and a need for conception support beyond specialized providers and fertility clinics. STUDY FUNDING/COMPETING INTEREST(S): The research reported in this publication was supported by the National Institute on Minority Health and Health Disparities of the National Institutes of Health (NIH), under award number R01MD015256. Additionally, KRSS is supported by NCI grant T32CA009001, AKH by the NCI T32CA057711, PC by the NHLBI T32HL098048, BM by the Stanford Maternal Child Health Research Institute Clinical Trainee Support Grant and the Diversity Fellowship from the American Society for Reproductive Medicine Research Institute, BGE by NICHD R01HD091405, and SM by the Thomas O. Pyle Fellowship through the Harvard Pilgrim Health Care Foundation and Harvard University, NHLBI T32HL098048, NIMH R01MH112384, and the William T. Grant Foundation grant number 187958. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. The first author recently had a leadership role in the not-for-profit program, The Lesbian Health Fund, a research fund focused on improving the health and wellbeing of LGBTQ+ women and girls. The fund did not have any role in this study and the author's relationship with the fund did not bias the findings of this manuscript. TRIAL REGISTRATION NUMBER: N/A.

3.
Int J Mol Sci ; 25(7)2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38612704

RESUMO

This study investigates the toxic effect of harmful materials, unfiltered by the placenta, on neonatal umbilical cord (UC) vessels, focusing on stress-induced adaptations in transcriptional and translational processes. It aims to analyze changes in pathways related to mRNA condensate formation, transcriptional regulation, and DNA damage response under maternal smoking-induced stress. UC vessels from neonates born to smoking (Sm) and nonsmoking mothers (Ctr) were examined. Immunofluorescence staining and confocal microscopy assessed the localization of key markers, including Transcription Complex Subunit 1 (CNOT1) and the largest subunit of RNA polymerase II enzyme (RPB1). Additionally, markers of DNA damage response, such as Poly(ADP-ribose) polymerase-1, were evaluated. In Sm samples, dissolution of CNOT1 granules in UC vessels was observed, potentially aiding stalled translation and enhancing transcription via RPB1 assembly and translocation. Control vessels showed predominant cytoplasmic RPB1 localization. Despite adaptive responses, Sm endothelial cells exhibited significant damage, indicated by markers like Poly(ADP-ribose) polymerase-1. Ex vivo metal treatment on control vessels mirrored Sm sample alterations, emphasizing marker roles in cell survival under toxic exposure. Maternal smoking induces specific molecular adaptations in UC vessels, affecting mRNA condensate formation, transcriptional regulation, and DNA damage response pathways. Understanding these intricate molecular mechanisms could inform interventions to improve neonatal health outcomes and mitigate adverse effects of toxic exposure during pregnancy.


Assuntos
Distrofias de Cones e Bastonetes , Células Endoteliais , Recém-Nascido , Humanos , Feminino , Gravidez , Regulação da Expressão Gênica , Transcrição Gênica , Poli(ADP-Ribose) Polimerases , RNA Mensageiro/genética , Fatores de Transcrição
4.
Perspect Sex Reprod Health ; 55(3): 178-191, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37571959

RESUMO

INTRODUCTION: During early stages of COVID-19 in the United States, government representatives in Kentucky, Ohio, and West Virginia restricted or threatened to restrict abortion care under elective surgery bans. We examined how abortion utilization changed in these states. METHODOLOGY: We examined COVID-19 abortion-related state policies implemented in March and April 2020 using publicly available sources. We analyzed data on abortions by method and gestation and experiences of facility staff, using a survey of 14 facilities. We assessed abortions that took place in February-June 2020 and February-June 2021. RESULTS: In February-June 2020 the monthly average abortion count was 1916; 863 (45%) were medication abortions and 229 (12%) were ≥14 weeks gestation. Of 1959 abortions performed across all three states in April 2020, 1319 (67%) were medication abortions and 231 (12%) were ≥14 weeks gestation. The shift toward medication abortion that took place in April 2020 was not observed in April 2021. Although the total abortion count in the three-state region remained steady, West Virginia had the greatest decline in total abortions, Ohio experienced a shift from instrumentation to medication abortions, and Kentucky saw little change. Staff reported increased stress from concerns over health and safety and increased scrutiny by the state and anti-abortion protesters. DISCUSSION: Although abortion provision continued in this region, policy changes restricting abortion in Ohio and West Virginia resulted in a decrease in first trimester instrumentation abortions, an overall shift toward medication abortion care, and an increase in stress among facility staff during the early phase of COVID-19.


Assuntos
Aborto Induzido , COVID-19 , Gravidez , Feminino , Estados Unidos , Humanos , Ohio/epidemiologia , West Virginia/epidemiologia , Kentucky/epidemiologia , Rios , COVID-19/epidemiologia , Aborto Legal
5.
Int J Mol Sci ; 23(23)2022 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-36499001

RESUMO

The relationship between smoking and human health has been investigated mostly in adults, despite the fact that the chemicals originating from sustained maternal smoking disrupt the carefully orchestrated regulatory cascades in the developing fetus. In this study, we followed molecular alterations in the umbilical cord (UC) vessels and fetal red blood cells (RBCs), which faithfully reflect the in vivo status of the fetus. We showed evidence for the decreased level of DNA-PKcs-positive nuclei in samples with smoking origin, which is associated with the impaired DNA repair system. Furthermore, we pointed out the altered ratio of MMP-9 metalloproteinase and its endogenous inhibitor TIMP-1, which might be a possible explanation for the morphological abnormalities in the UC vessels. The presented in vivo dataset emphasizes the higher vulnerability of the veins, as the primary target for the toxic materials unfiltered by the placenta. All these events become amplified by the functionally impaired fetal RBC population via a crosstalk mechanism between the vessel endothelium and the circulating RBCs. In our ex vivo approach, we looked for the molecular explanation of metal-exposure-induced alterations, where expressions of the selected genes were upregulated in the control group, while samples with smoking origin showed a lack of response, indicative of prior long-term in utero exposure.


Assuntos
Placenta , Cordão Umbilical , Gravidez , Adulto , Feminino , Humanos , Feto , Fumar/efeitos adversos , Eritrócitos/química , Sangue Fetal/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-31926297

RESUMO

Maternal smoking-induced congenital heart and microvascular defects are closely associated with the impaired functioning of the in-utero feto-placental circulation system. Current groundbreaking facts revealed intimate crosstalk between circulating red blood cells (RBCs) and the vascular endothelium. Thus, RBCs have become the protagonists under varied pathological and adverse pro-oxidative cellular stress conditions. We isolated and screened fetal RBCs from the arterial cord blood of neonates, born to non-smoking (RBC-NS) and smoking mothers (RBC-S), assuming that parameters of fetal RBCs are blueprints of conditions experienced in-utero. Using atomic force microscopy and mass spectrometry-based shotgun lipidomics in the RBC-S population we revealed induced membrane stiffness, loss in intrinsic plastic activities and several abnormalities in their membrane-lipid composition, that could consequently result in perturbed hemodynamic flow movements. Altogether, these features are indicative of the outcome of neonatal microvascular complications and suggest unavailability for the potential rescue mechanism in cases of vascular endothelium impairment due to altered membrane integrity and rheological properties.


Assuntos
Eritrócitos/patologia , Sangue Fetal/citologia , Efeitos Tardios da Exposição Pré-Natal/etiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Adulto , Fenômenos Biomecânicos , Membrana Eritrocítica/química , Membrana Eritrocítica/patologia , Eritrócitos/química , Feminino , Hemodinâmica , Humanos , Recém-Nascido , Peroxidação de Lipídeos , Fluidez de Membrana , Lipídeos de Membrana/análise , Gravidez , Efeitos Tardios da Exposição Pré-Natal/patologia , Adulto Jovem
8.
Oxid Med Cell Longev ; 2019: 1509798, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31871538

RESUMO

An understanding of the basic pathophysiological mechanisms of neonatal diseases necessitates detailed knowledge about the wide range of complications in the circulating fetal RBCs. Recent publications on adult red blood cells (RBCs) provide evidence that RBCs carry an active nitric oxide synthase (NOS3) enzyme and contribute to vascular functioning and integrity via their active nitric oxide synthesis. The aim of this study was to determine the effect of maternal smoking on the phenotypical appearance and functionality of fetal RBCs, based on morphological and molecular studies. We looked for possible links between vascular dysfunction and NOS3 expression and activation and its regulation by arginase (ARG1). Significant morphological and functional differences were found between fetal RBCs isolated from the arterial cord blood of neonates born to nonsmoking (RBC-NS, n = 62) and heavy-smoking (RBC-S, n = 51) mothers. Morphological variations were quantified by Advanced Cell Classifier, microscopy-based intelligent analysis software. To investigate the relevance of the newly suggested "erythrocrine" function in fetal RBCs, we measured the levels of NOS3 and its phosphorylation in parallel with the level of ARG1, as one of the major influencers of NOS3 dimerization, by fluorescence-activated cell sorting. Fetal RBCs, even the "healthy-looking" biconcave-shaped type, exhibited impaired NOS3 activation in the RBC-S population, which was paralleled with elevated ARG1 level, thus suggesting an increased redox burden. Our molecular data indicate that maternal smoking can exert marked effects on the circulating fetal RBCs, which could have a consequence on the outcome of in utero development. We hypothesize that any endothelial dysfunction altering NO production/bioavailability can be sensed by circulating fetal RBCs. Hence, we are putting forward the idea that neonatal RBC could serve as a real-time sensor for not only monitoring RBC-linked anomalies but also predicting the overall status of the vascular microenvironment.


Assuntos
Acetatos/toxicidade , Cádmio/toxicidade , Eritrócitos/metabolismo , Exposição Materna/efeitos adversos , Fumar/efeitos adversos , Arginase/metabolismo , Candida/patogenicidade , Células Cultivadas , Eritrócitos/efeitos dos fármacos , Feminino , Sangue Fetal/metabolismo , Humanos , Óxido Nítrico Sintase Tipo III/metabolismo , Ácido Peroxinitroso/metabolismo , Fosforilação , Gravidez
9.
Chem Biol Interact ; 313: 108821, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525342

RESUMO

Decrease in the bioavailability of vasoactive nitric oxide (NO), derived from the endothelial nitric oxide synthase (NOS3), underlines vascular endothelial damage. Our expanding knowledge on mature red blood cells (RBCs) makes it supposable that RBCs might contribute to vascular function and integrity via their active NO synthetizing system (RBC-NOS3). This "rescue" mechanism of RBCs could be especially important during pregnancy with smoking habit, when smoking acts as an additional stressor and causes active change in the redox status. In this study RBC populations of 82 non-smoking (RBC-NS) and 75 smoking (RBC-S) pregnant women were examined. Morphological variants were followed by confocal microscopy and quantified by a microscopy based intelligent analysis software. Fluorescence activated cell sorting was used to examine the translational and posttranslational regulation of RBC-NOS, Arginase-1 and the formation of the major product of lipid peroxidation, 4-hydroxy-2-nonenal. To survey the rheological parameters of RBCs like elasticity and plasticity atomic force microscopy-based measurement was applied. Significant morphological and functional differences of RBCs were found between the non-smoking and smoking groups. The phenotypic variations in RBC-S population, even the characteristic biconcave disc-shaped cells, could be connected to impaired NOS3 activation and are compromised in their physiological properties. Membrane lipid studies reveal an elevated lipid oxidation state well paralleled with the changed elastic and plastic activities. These features can form a basic tool in the prenatal health screening conditions; hence the compensatory mechanism of RBC-S population completely fails to sense and rescue the acute oxidative stress conditions.


Assuntos
Arginase/metabolismo , Eritrócitos/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Óxido Nítrico/metabolismo , Fumar/efeitos adversos , Adulto , Aldeídos/metabolismo , Estudos de Casos e Controles , Morte Celular/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Feminino , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Microscopia de Força Atômica , Gravidez
10.
Front Immunol ; 10: 264, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30984160

RESUMO

Effective prophylactic strategy against the current epidemic of sexually transmitted HIV-1 infection requires understanding of the innate gatekeeping mechanisms at the genital mucosa. Surfactant protein D (SP-D), a member of the collectin family of proteins naturally present in the vaginal tract, is a potential HIV-1 entry inhibitor at the cellular level. Human EpiVaginal tissues compartmentalized in culture inserts were apically exposed to HIV-1 and/or a recombinant fragment of human SP-D (rfhSP-D) and viral passage was assessed in the basal chamber containing mononuclear leukocytes. To map the gene signature facilitating or resisting the transepithelial viral transfer, microarray analysis of the HIV-1 challenged EpiVaginal tissues was performed in the absence or presence of rfhSP-D. Mucosal biocompatibility of rfhSP-D was assessed ex vivo and in the standard rabbit vaginal irritation model. The passage of virus through the EpiVaginal tissues toward the underlying target cells was associated with a global epithelial gene signature including differential regulation of genes primarily involved in inflammation, tight junctions and cytoskeletal framework. RfhSP-D significantly inhibited HIV-1 transfer across the vaginal tissues and was associated with a significant reversal of virus induced epithelial gene signature. Pro-inflammatory NF-κB and mTOR transcripts were significantly downregulated, while expression of the tight junctions and cytoskeletal genes was upheld. In the absence of virus, rfhSP-D directly interacted with the EpiVaginal tissues and upregulated expression of genes related to structural stability of the cell and epithelial integrity. There was no increment in the viral acquisition by the PBMCs present in basal chambers wherein, the EpiVaginal tissues in apical chambers were treated with rfhSP-D. The effective concentrations of rfhSP-D had no effect on lactobacilli, epithelial barrier integrity and were safe on repeated applications onto the rabbit vaginal mucosa. This pre-clinical safety data, coupled with its efficacy of restricting viral passage via reversal of virus-induced gene expression of the vaginal barrier, make a strong argument for clinical trials of rfhSP-D as a topical anti-HIV microbicide.


Assuntos
Células Epiteliais/imunologia , Expressão Gênica/imunologia , HIV-1/imunologia , Lactobacillus/imunologia , Proteína D Associada a Surfactante Pulmonar/imunologia , Vagina/imunologia , Vagina/virologia , Animais , Linhagem Celular , Células Epiteliais/virologia , Feminino , Soropositividade para HIV/genética , Soropositividade para HIV/imunologia , HIV-1/genética , Humanos , Imunidade nas Mucosas/imunologia , Inflamação/imunologia , Inflamação/virologia , NF-kappa B/imunologia , Coelhos , Serina-Treonina Quinases TOR/imunologia , Regulação para Cima/imunologia
11.
Biochim Biophys Acta Gen Subj ; 1861(8): 2048-2059, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28411076

RESUMO

BACKGROUND: NSAIDs are the most common class of painkillers and anti-inflammatory agents. They also show other functions like chemoprevention and chemosuppression for which they act at the protein but not at the genome level since they are mostly anions at physiological pH, which prohibit their approach to the poly-anionic DNA. Complexing the drugs with bioactive metal obliterate their negative charge and allow them to bind to the DNA, thereby, opening the possibility of genome level interaction. To test this hypothesis, we present the interaction of a traditional NSAID, Piroxicam and its copper complex with core histone and chromatin. METHODS: Spectroscopy, DLS, and SEM studies were applied to see the effect of the interaction on the structure of histone/chromatin. This was coupled with MTT assay, immunoblot analysis, confocal microscopy, micro array analysis and qRT-PCR. RESULTS: The interaction of Piroxicam and its copper complex with histone/chromatin results in structural alterations. Such structural alterations can have different biological manifestations, but to test our hypothesis, we have focused only on the accompanied modulations at the epigenomic/genomic level. The complex, showed alteration of key epigenetic signatures implicated in transcription in the global context, although Piroxicam caused no significant changes. We have correlated such alterations caused by the complex with the changes in global gene expression and validated the candidate gene expression alterations. CONCLUSION AND GENERAL SIGNIFICANCE: Our results provide the proof of concept that DNA binding ability of the copper complexes of a traditional NSAID, opens up the possibility of modulations at the epigenomic/genomic level.


Assuntos
Anti-Inflamatórios não Esteroides/química , Cromatina/química , Cobre/química , Epigenômica , Piroxicam/química , Cobre/metabolismo , DNA/metabolismo , Células HeLa , Histonas/química , Humanos , Piroxicam/metabolismo , Espectrometria de Fluorescência , Transcriptoma
12.
Syst Biol Reprod Med ; 63(1): 37-48, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28045561

RESUMO

Women are born with millions of primordial follicles which gradually decrease with increasing age and this irreversible supply of follicles completely exhausts at menopause. The fertility capacity of women diminishes in parallel with aging. The mechanisms for reproductive aging are not fully understood. We have observed a decline in Brca1 mediated DNA repair in aging rat primordial follicles. To further understand the age-related molecular changes, we performed microarray gene expression analysis using total RNA extracted from immature (18 to 20 day old) and aged (400 to 450 day old) rat primordial follicles. The results of current microarray study revealed that there were 1,011 (>1.5 fold, p<0.05) genes differentially expressed between two groups in which 422 genes were up-regulated and 589 genes were down-regulated in aged rat primordial follicles compared to immature primordial follicles. The gene ontology and pathway analysis of differentially expressed genes revealed a critical biological function such as cell cycle, oocyte meiosis, chromosomal stability, transcriptional activity, DNA replication, and DNA repair were affected by age. This considerable difference in gene expression profiles may have an adverse influence on oocyte quality. Our data provide information on the processes that may contribute to aging and age-related decline in fertility.


Assuntos
Envelhecimento/genética , Fertilidade/genética , Regulação da Expressão Gênica no Desenvolvimento , Folículo Ovariano/metabolismo , Fatores Etários , Animais , Feminino , Perfilação da Expressão Gênica/métodos , Redes Reguladoras de Genes , Análise de Sequência com Séries de Oligonucleotídeos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcriptoma
13.
J Biomol Struct Dyn ; 35(7): 1491-1499, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27494525

RESUMO

Chelerythrine (CHL), a plant alkaloid, possesses antimicrobial, anti-inflammatory, and antitumor properties. Although CHL influences several key signal transduction pathways, its ability to interact directly with nucleoprotein complex chromatin, in eukaryotic cells has so far not been looked into. Here we have demonstrated its association with hierarchically assembled chromatin components, viz. long chromatin, chromatosome, nucleosome, chromosomal DNA, and histone H3 and the consequent effect on chromatin structure. CHL was found to repress acetylation at H3K9. It is more target-specific in terms of gene expression alteration and less cytotoxic compared to its structural analog sanguinarine.


Assuntos
Antineoplásicos/farmacologia , Benzofenantridinas/farmacologia , Eucromatina/efeitos dos fármacos , Histonas/metabolismo , Nucleossomos/efeitos dos fármacos , Processamento de Proteína Pós-Traducional , Acetilação/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Montagem e Desmontagem da Cromatina , DNA/química , DNA/metabolismo , Epigênese Genética , Eucromatina/química , Eucromatina/metabolismo , Células HeLa , Histonas/genética , Humanos , Isoquinolinas/farmacologia , Nucleossomos/química , Nucleossomos/metabolismo , Regiões Promotoras Genéticas
14.
J Pathol ; 240(3): 269-281, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27453350

RESUMO

Alveolar rhabdomyosarcoma (ARMS) is an aggressive paediatric cancer of skeletal muscle with poor prognosis. A PAX3-FOXO1 fusion protein acts as a driver of malignancy in ARMS by disrupting tightly coupled but mutually exclusive pathways of proliferation and differentiation. While PAX3-FOXO1 is an attractive therapeutic target, no current treatments are designed to block its oncogenic activity. The present work shows that the histone acetyltransferase P/CAF (KAT2B) is overexpressed in primary tumours from ARMS patients. Interestingly, in fusion-positive ARMS cell lines, P/CAF acetylates and stabilizes PAX3-FOXO1 rather than MyoD, a master regulator of muscle differentiation. Silencing P/CAF, or pharmacological inhibition of its acetyltransferase activity, down-regulates PAX3-FOXO1 levels concomitant with reduced proliferation and tumour burden in xenograft mouse models. Our studies identify a P/CAF-PAX3-FOXO1 signalling node that promotes oncogenesis and may contribute to MyoD dysfunction in ARMS. This work exemplifies the therapeutic potential of targeting chromatin-modifying enzymes to inhibit fusion oncoproteins that are a frequent event in sarcomas. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Carcinogênese/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Fusão Oncogênica/metabolismo , Fatores de Transcrição Box Pareados/metabolismo , Processamento de Proteína Pós-Traducional , Rabdomiossarcoma Alveolar/genética , Fatores de Transcrição de p300-CBP/metabolismo , Animais , Carcinogênese/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Epigenômica , Inativação Gênica , Xenoenxertos , Camundongos , Camundongos Nus , Músculos/patologia , Proteína MyoD/genética , Proteína MyoD/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas de Fusão Oncogênica/genética , Fatores de Transcrição Box Pareados/genética , Rabdomiossarcoma Alveolar/patologia , Transdução de Sinais , Fatores de Transcrição de p300-CBP/genética
15.
Biochem Biophys Res Commun ; 462(4): 352-7, 2015 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-25960297

RESUMO

Recognition of core histone components of chromatin along with chromosomal DNA by a class of small molecule modulators is worth examining to evaluate their intracellular mode of action. A plant alkaloid ellipticine (ELP) which is a putative anticancer agent has so far been reported to function via DNA intercalation, association with topoisomerase II and binding to telomere region. However, its effect upon the potential intracellular target, chromatin is hitherto unreported. Here we have characterized the biomolecular recognition between ELP and different hierarchical levels of chromatin. The significant result is that in addition to DNA, it binds to core histone(s) and can be categorized as a 'dual binder'. As a sequel to binding with histone(s) and core octamer, it alters post-translational histone acetylation marks. We have further demonstrated that it has the potential to modulate gene expression thereby regulating several key biological processes such as nuclear organization, transcription, translation and histone modifications.


Assuntos
Cromatina/efeitos dos fármacos , Elipticinas/farmacologia , Acilação , Cromatina/metabolismo , Dicroísmo Circular , Histonas/metabolismo , Ligação Proteica , Espectrometria de Fluorescência
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