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Migration and invasion enhancer 1 (MIEN1) overexpression characterizes several cancers and facilitates cancer cell migration and invasion. Leveraging conserved immunoreceptor tyrosine-based activation motif and prenylation motifs within MIEN1, we identified potent anticancer peptides. Among them, bioactive peptides LA3IK and RP-7 induced pronounced transcriptomic and protein expression changes at sub-IC50 concentrations. The peptides effectively inhibited genes and proteins driving cancer cell migration, invasion, and epithelial-mesenchymal transition pathways, concurrently suppressing epidermal growth factor-induced nuclear factor kappa B nuclear translocation in metastatic breast cancer cells. Specifically, peptides targeted the same signal transduction pathway initiated by MIEN1. Molecular docking and CD spectra indicated the formation of MIEN1-peptide complexes. The third-positioned isoleucine in LA3IK and CVIL motif in RP-7 were crucial for inhibiting breast cancer cell migration. This is evident from the limited migration inhibition observed when MDA-MB-231 cells were treated with scrambled peptides LA3IK SCR and RP-7 SCR. Additionally, LA3IK and RP-7 effectively suppressed tumor growth in an orthotopic breast cancer model. Notably, mice tolerated high intraperitoneal (ip) peptide doses of 90 mg/Kg well, surpassing significantly lower doses of 5 mg/Kg intravenously (iv) and 30 mg/Kg intraperitoneally (ip) used in both in vivo pharmacokinetic studies and orthotopic mouse model assays. D-isomers of LA3IK and RP-7 showed enhanced anticancer activity compared to their L-isomers. D-LA3IK remained stable in mouse plasma for 24 h with 75% remaining, exhibiting superior pharmacokinetic properties over D/L-RP-7. In summary, our findings mark the first report of short peptides based on MIEN1 protein sequence capable of inhibiting cancer signaling pathways, effectively impeding cancer progression both in vitro and in vivo.
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Peptídeos e Proteínas de Sinalização Intracelular , Proteínas de Neoplasias , Animais , Camundongos , Movimento Celular/genética , Proliferação de Células , Transição Epitelial-Mesenquimal , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Simulação de Acoplamento Molecular , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Transdução de Sinais , Humanos , Linhagem Celular , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologiaRESUMO
BACKGROUND: With an overarching goal of increasing diversity and inclusion in biomedical sciences, the National Research Mentoring Network (NRMN) developed a web-based national mentoring platform (MyNRMN) that seeks to connect mentors and mentees to support the persistence of underrepresented minorities in the biomedical sciences. As of May 15, 2024, the MyNRMN platform, which provides mentoring, networking, and professional development tools, has facilitated more than 12,100 unique mentoring connections between faculty, students, and researchers in the biomedical domain. OBJECTIVE: This study aimed to examine the large-scale mentoring connections facilitated by our web-based platform between students (mentees) and faculty (mentors) across institutional and geographic boundaries. Using an innovative graph database, we analyzed diverse mentoring connections between mentors and mentees across demographic characteristics in the biomedical sciences. METHODS: Through the MyNRMN platform, we observed profile data and analyzed mentoring connections made between students and faculty across institutional boundaries by race, ethnicity, gender, institution type, and educational attainment between July 1, 2016, and May 31, 2021. RESULTS: In total, there were 15,024 connections with 2222 mentees and 1652 mentors across 1625 institutions contributing data. Female mentees participated in the highest number of connections (3996/6108, 65%), whereas female mentors participated in 58% (5206/8916) of the connections. Black mentees made up 38% (2297/6108) of the connections, whereas White mentors participated in 56% (5036/8916) of the connections. Mentees were predominately from institutions classified as Research 1 (R1; doctoral universities-very high research activity) and historically Black colleges and universities (556/2222, 25% and 307/2222, 14%, respectively), whereas 31% (504/1652) of mentors were from R1 institutions. CONCLUSIONS: To date, the utility of mentoring connections across institutions throughout the United States and how mentors and mentees are connected is unknown. This study examined these connections and the diversity of these connections using an extensive web-based mentoring network.
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Tutoria , Mentores , Humanos , Tutoria/métodos , Mentores/estatística & dados numéricos , Feminino , Masculino , Pesquisa Biomédica/estatística & dados numéricos , Estados Unidos , Grupos Minoritários/estatística & dados numéricos , Bases de Dados Factuais , Docentes/estatística & dados numéricosRESUMO
Research innovation that leads to discovery in the battle against neurological disease and disorders requires diverse ideas. The National Institute of Neurological Disorders and Stroke, one of the National Institutes of Health's 27 institutes and centers, strives to reduce the burden of neurological disease and disorders. The National Institutes of Neurologic Disorders and Stroke is very interested in increasing the diversity of researchers by addressing the existing barriers responsible for the low numbers of underrepresented populations from traditionally minority-serving institutions (MSIs) and non-minority serving institutions (non-MSIs). This commentary provides insight on the persistent underrepresentation of racial/ethnic minorities entering neuroscience research careers paths, focusing on multiples levels within the scientific academy and the supportive role that both MSIs and non-MSIs play in increasing diversity in the biomedical research workforce.
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National Institute of Neurological Disorders and Stroke (USA) , Doenças do Sistema Nervoso , Humanos , Grupos Minoritários , Pesquisadores , Estados Unidos , Recursos HumanosRESUMO
PURPOSE: Increased awareness and mitigation of one's unconscious bias is a critical strategy in diversifying the Science, Technology, Engineering, Mathematics, and Medicine (STEMM) disciplines and workforce. Greater management of unconscious bias can enhance diverse recruitment, persistence, retention, and engagement of trainees. The purpose of this study was to describe the implementation of an asynchronous course on unconscious bias for people in STEMM. Specifically, we explored who engaged with the course and reflections from participation. METHOD: A five-part, asynchronous Unconscious Bias Course was developed and was hosted on a national mentoring platform starting in July 2020. To examine course engagement, we assessed the demographics of course participants and completion. Participant responses to reflection questions after each module were also synthesized using qualitative methods. RESULTS: Overall, 977 people registered for the course and 42% completed all modules. In the reflection responses, participants reflected on their unconscious biases in their lived experiences and how it relates to actions, judgements, external factors, stereotypes, and un-intentionality. Participants also reflected on microaggressions, their impact on the recipients and others, and the relationship between microaggressions and unconscious bias. Participants reported four key strategies used by allies against unconscious bias: immediately acting (83%), reflection (46%), improving the organizational culture (30%), and individual-level ally-ship (44%). Strategies for self-awareness included: reflection, pausing/breathing, and self-observation. CONCLUSION: The assessment of the Unconscious Bias Course implementation revealed the course reached a wide cross-section of people in STEMM and demonstrated that participants were able to reflect on the underpinnings of the course. This course, and its suite of offerings, support a nationwide effort to mitigate bias and prepare individuals to be culturally competent in a diverse society in order to foster a STEMM environment that caters to individuals' success and diversification of these fields.
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Medicina , Tutoria , Viés , Viés Implícito , Humanos , Mentores , Recursos HumanosRESUMO
Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) has infected >235 million people and killed over 4.8 million individuals worldwide. Although vaccines have been developed for prophylactic management, there are no clinically proven antivirals to treat the viral infection. Continuous efforts are being made all over the world to develop effective drugs but these are being delayed by periodic outbreak of mutated SARS-CoV-2 and a lack of knowledge of molecular mechanisms underlying viral pathogenesis and post-infection complications. In this regard, the involvement of Annexin A2 (AnxA2), a lipid-raft related phospholipid-binding protein, in SARS-CoV-2 attachment, internalization, and replication has been discussed. In addition to the evidence from published literature, we have performed in silico docking of viral spike glycoprotein and RNA-dependent RNA polymerase with human AnxA2 to find the molecular interactions. Overall, this review provides the molecular insights into a potential role of AnxA2 in the SARS-CoV-2 pathogenesis and post-infection complications, especially thrombosis, cytokine storm, and insulin resistance.
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Anexina A2/metabolismo , COVID-19/patologia , Anexina A2/química , COVID-19/virologia , Síndrome da Liberação de Citocina/metabolismo , Síndrome da Liberação de Citocina/patologia , Humanos , Simulação de Acoplamento Molecular , RNA Polimerase Dependente de RNA/química , RNA Polimerase Dependente de RNA/metabolismo , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/metabolismo , Trombose/metabolismo , Trombose/patologia , Internalização do VírusRESUMO
BACKGROUND: Limited information is available on biomarker(s) for triple-negative breast cancer (TNBC) that can address the higher incidence and aggressiveness of TNBC in African-American (AA) women. Our previous studies have demonstrated annexin A2 (AnxA2) association with exosomes which promotes angiogenesis and metastasis. Therefore, our goal was to examine the expression and function of exosomal-annexin A2 (exo-AnxA2) derived from the serum samples of breast cancer patients. METHODS: The expression of serum exo-AnxA2 and its association with clinicopathological features of the breast cancer patients were determined. The role of serum exo-AnxA2 to promote angiogenesis was determined by an in vivo Matrigel plug assay. RESULTS: Our results show that the expression of serum exo-AnxA2 in breast cancer patients (n = 169; 83.33 ± 2.040 ng/mL, P < 0.0001) is high compared to non-cancer females (n = 68; 34.21 ± 2.238 ng/mL). High expression of exo-AnxA2 levels in breast cancer was significantly associated with tumor grade (P < 0.0001), poor overall survival (hazard ratio (HR) 2.802; 95% confidence intervals (CI) = 1.030-7.620; P = 0.0353), and poor disease-free survival (HR 7.934; 95% CI = 1.778-35.398; P = 0.0301). The expression of serum exo-AnxA2 levels was significantly elevated in TNBC (n = 68; 109.1 ± 2.905 ng/mL; P < 0.0001) in comparison to ER+ (n = 50; 57.35 ± 1.545 ng/mL), HER2+ (n = 59; 78.25 ± 1.146 ng/mL), and non-cancer females (n = 68; 34.21 ± 2.238 ng/mL). Exo-AnxA2 showed diagnostic values with a maximum AUC as 1.000 for TNBC, 0.8304 for ER+, and 0.9958 for HER2+ compared to non-cancer females. The expression of serum exo-AnxA2 was significantly elevated in AA women with TNBC (n = 29; 118.9 ± 4.086 ng/mL, P < 0.0001) in comparison to Caucasian-American TNBC (n = 27; 97.60 ± 3.298 ng/mL) patients. Our in vivo results suggest a role of serum exo-AnxA2 in angiogenesis and its association with aggressiveness of TNBC in AA women. CONCLUSIONS: Our results demonstrated that the expression of serum exo-AnxA2 is high in AA women with TNBC and promotes angiogenesis. These findings suggest that exo-AnxA2 holds promise as a potential prognosticator of TNBC and may lead to an effective therapeutic option.
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Anexina A2/sangue , Biomarcadores Tumorais/sangue , Negro ou Afro-Americano/estatística & dados numéricos , Exossomos/metabolismo , Neovascularização Patológica/patologia , Neoplasias de Mama Triplo Negativas/irrigação sanguínea , Animais , Feminino , Humanos , Camundongos , Camundongos Nus , Gradação de Tumores , Neovascularização Patológica/metabolismo , Curva ROC , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
After publication of the original article [1], we were notified that the wrong version of Fig. 2b has been published.
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PURPOSE: Our aim was to determine the role of Annexin A2 (AnxA2), which we have previously found to contribute to the aggressiveness of TNBC, with AA TNBC patients and clinical outcome. METHODS: We analyzed TCGA breast cancer database (n = 1098) to observe AnxA2 expression within breast cancer subtypes and is correlation with overall survival. Further, we examined breast tissue specimens (n = 119) through chromogenic in situ hybridization (CISH) and specimen were scored independently by two pathologists in a blinded study. RESULTS: In our TCGA analysis, high expression of AnxA2 was correlated with poor survival in patients with TNBC. AnxA2 gene expression was not correlated with poor survival in other breast cancer subtypes. AnxA2 average CISH intensity score (CISH score = 0, null expression to 3, high expression) for TNBC was significantly higher in comparison to estrogen receptor and/or progesterone receptor positive, human epidermal growth factor positive, and non-malignant tissues. Furthermore, AnxA2 average score was significantly higher in AA TNBC patients (CISH average score = 2.45 ± 0.3266) in comparison to Caucasian TNBC patients (CISH average score = 1.1 ± 0.4069). CONCLUSION: AnxA2 is overexpressed in TNBC, implicating AnxA2 as a contributor to the aggressive biology of TNBC in AA women.
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Anexina A2/biossíntese , Neoplasias de Mama Triplo Negativas/patologia , Adulto , Negro ou Afro-Americano , Idoso , Biomarcadores Tumorais/análise , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Prognóstico , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/mortalidadeRESUMO
Brain metastatic breast cancer is challenging to treat due to the presence of the blood-brain barrier (BBB) and a lack of ability to target precisely. Most drugs fail to cross the BBB limiting their effectiveness. To combat this problem, a brain metastatic breast cancer cell (MDA-MB-831) membrane-coated polymeric nanoparticle (CCNP) was synthesized. The small size (â¼70 nm) and anionic surface charge (-20 mV) achieved during formulation allowed for high penetration and retention in the brain when compared to the PEGylated polymeric nanoparticle alone (mPEG-PLGA or NP). Doxorubicin-loaded CCNP showed high preferential cytotoxicity in vitro. Live (4-120 h) and ex vivo near-infrared imaging in nude mice showed extended circulation and retention of CCNP compared to uncoated nanoparticles. These data indicate that drug/dye-loaded CCNPs demonstrate excellent potential for cancer theranostics of brain metastatic breast tumors.
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Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/secundário , Neoplasias da Mama/tratamento farmacológico , Doxorrubicina/administração & dosagem , Polímeros/química , Animais , Barreira Hematoencefálica , Linhagem Celular Tumoral , Doxorrubicina/química , Doxorrubicina/farmacocinética , Feminino , Humanos , Camundongos , Camundongos Nus , Nanoconjugados/química , Tamanho da Partícula , Espectroscopia de Luz Próxima ao Infravermelho , Nanomedicina Teranóstica , Distribuição Tecidual , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Annexin A2 has been implicated in several immune modulated diseases including Rheumatoid arthritis (RA) pannus formation. The most relied treatment option for RA pathogenesis is glucocorticoids. Glucocorticoids regulate the synthesis, phosphorylation and cellular deposition of Annexin A1. This annexin mediates the anti-inflammatory actions of glucocorticoids. These two first characterized members of annexin superfamily proteins acts reciprocally, one as an anti-inflammatory and the other proinflammatory in nature. The possibility of these molecules as soluble biomarkers and as an upstream regulator of major cytokine devastation at RA microenvironment has not been previously explored. Current study elucidates the reciprocal regulation of these two annexins in RA pathogenesis. These Annexin A2/A1 and downstream cytokines in RA serum were analysed by ELISA. Western blot, Immunocytochemistry, immunoprecipitation and Immunohistochemistry were adapted to analyse these molecules in tissue and synovial fibroblasts and also in different experimental conditions. Significant increase in the level of Annexin A2 was noticed in naïve RA patients compared to controls (14.582 ± 1.766 ng/ml vs. 7.37 ± 1.450 ng/ml; p ≤ 0.001). In remission cases significant low levels was detected. On the contrary, significant decrease in the level of Annexin A1 was noticed in naïve RA patients compared to healthy controls (12.322 ± 2.91 vs. 16.998 ± 4.298 ng/ml; p ≤ 0.001), wherein remission cases serum Annexin A1 was significantly high. The knockdown of proinflammatory Annexin A2 by siRNA/antibody treatment could mimic the glucocorticoid treatment as which induced cellular Annexin A1 and membrane translocation resulting in the terminal action. Current data elucidating the regulatory interplay between Annexin A2 and Annexin A1 in RA pathogenesis.
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Anexina A1/fisiologia , Anexina A2/fisiologia , Artrite Reumatoide/patologia , Adulto , Anexina A1/sangue , Anexina A2/sangue , Anexina A2/metabolismo , Anti-Inflamatórios , Feminino , Fibroblastos/metabolismo , Glucocorticoides/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Membrana Sinovial/metabolismoRESUMO
BACKGROUND/AIMS: Targeting survivin, an anti-apoptotic protein and mitotic regulator, is considered as an effective therapeutic option for pancreatic cancer (PaCa). Tolfenamic acid (TA) showed anti-cancer activity in pre-clinical studies. A recent discovery demonstrated a copper(II) complex of TA (Cu-TA) can result in higher activity. In this study, the ability of Cu-TA to inhibit survivin and its transcription factors, Specificity protein (Sp) 1 and 3 in PaCa cell lines and tumor growth in mouse xenograft model were evaluated. METHODS: Cell growth inhibition was measured in MIA PaCa-2 and Panc1 cells for 2 days using CellTiter-Glo kit. Sp1, Sp3 and survivin expression (by Western blot and qPCR), apoptotic cells and cell cycle phase distribution (by flow cytometry) were evaluated. A pilot study was performed using athymic nude mice [treated with vehicle/Cu-TA (25 or 50 mg/kg) 3 times/week for 4 weeks. RESULTS: The IC50 value for Cu-TA was about half than TA.Both agents repressed the protein expression of Sp1/Sp3/survivin, Cu-TA was more effective than TA. Especially effect on survivin inhibition was 5.2 (MIA PaCa-2) or 6.4 (Panc1) fold higher and mRNA expression of only survivin was decreased. Apoptotic cells increased with Cu-TA treatment in both cell lines, while Panc1 showed both effect on apoptosis and cell cycle (G2/M) arrest. Cu-TA decreased the tumor growth in mouse xenografts (25 mg/kg: 48%; 50 mg/kg: 68%). Additionally, there was no change observed in mice body weights, indicating no overt toxicity was occurring. CONCLUSION: These results show that Cu-TA can serve as an effective survivin inhibitor for inhibiting PaCa cell growth.
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Antineoplásicos/uso terapêutico , Cobre/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp3/genética , Survivina/antagonistas & inibidores , ortoaminobenzoatos/uso terapêutico , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Complexos de Coordenação/química , Complexos de Coordenação/uso terapêutico , Cobre/química , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Masculino , Camundongos , Camundongos Nus , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , ortoaminobenzoatos/químicaRESUMO
The Texas Center for Health Disparities (TCHD) at the University of North Texas Health Science Center is a National Institute on Minority Health and Health Disparities-funded, specialized center of excellence for health disparities. TCHD organized its 12th annual conference focusing on "Evidence-Based Approaches to Reduce Cancer Health Disparities: Discover, Develop, Deliver, and Disseminate." At this conference, experts in health care, biomedical sciences, and public health gathered to discuss the current status and strategies for reducing cancer health disparities. The meeting was conducted in three sessions on breast cancer, prostate cancer, and colorectal cancer disparities, in addition to roundtable discussions and a poster session. Each session highlighted differences in the effects of cancer, based on factors such as race/ethnicity, gender, socioeconomic status, and geographical location. In each session, expert speakers presented their findings, and this was followed by a discussion panel made up of experts in that field and cancer survivors, who responded to questions from the audience. This article summarizes the approaches to fundamental, translational, clinical, and public health issues in cancer health disparities discussed at the conference.
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Eliminating disparities in health can benefit from the inclusion of diverse populations pursuing health disparity research careers. A goal of the Texas Center for Health Disparities (TCHD) is to provide opportunities for underrepresented minority faculty to become successful health disparity researchers. The TCHD created the Steps Toward Academic Research (STAR) fellowship program to provide faculty and community partners a yearlong face-to-face and online hybrid curriculum focused on acquiring fundamental concepts in biomedical and behavioral health disparity research, basics in grantsmanship as well as professional development skills. In total, this training approach is envisioned to provide mutually beneficial co-learning experiences that will increase the number of under-represented minorities (URMs) entering translational research focused on the elimination of health disparities.
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Etnicidade/educação , Bolsas de Estudo/organização & administração , Disparidades nos Níveis de Saúde , Grupos Minoritários , Pesquisadores/educação , Pesquisa/educação , Currículo , Docentes , Bolsas de Estudo/estatística & dados numéricos , Feminino , Organização do Financiamento , Humanos , Masculino , Pesquisa/economia , TexasRESUMO
The expression of specificity protein 1 (Sp1) and survivin was evaluated in clinical specimens of epithelial ovarian cancer (EOC) patients. When compared to normal tissue, EOC samples showed high expression of Sp1 and survivin using qPCR (Sp1: â¼2-fold; survivin: â¼5-fold) and Western blot (Sp1: >2.6-fold; survivin: >100-fold). The Sp1 inhibitor, and anti-cancer small molecule, tolfenamic acid (TA), was tested to enhance the response of Cisplatin (Cis) in EOC cell lines. Cell viability (CellTiter-Glo), combination index (CalcuSyn software), apoptosis (Annexin-V staining), cell cycle analyses (flow cytometry), and reactive oxygen species (flow cytometry) were determined. Cell migration and invasion was assessed using matrigel coated transwell chambers. Agilent Technologies proteomics analysis identified potential signaling pathways involved. The combination of TA (50 µM) and Cis (5 µM) synergistically increased the growth inhibition in ES2 (â¼80 %, p < 0.001) and OVCAR-3 (60 %, p < 0.001) cells. TA or TA + Cis treatment in ES2 cells caused cell cycle arrest in G1 Phase (TA) or S-Phase (TA + Cis) and unregulated reactive oxygen species. Invasion and migration was decreased in ES2 cells. Global proteomic profiling showed modulation of proteins associated with oxidative phosphorylation, apoptosis, electron transport chain, DNA damage, and cell cycle proteins. These results demonstrate an association of Sp1 and survivin in EOC and confirm targeting these candidates with TA potentially sensitizes EOC cells to cisplatin.
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Proliferação de Células/efeitos dos fármacos , Cisplatino/farmacologia , Proteínas Inibidoras de Apoptose/metabolismo , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Epiteliais e Glandulares/patologia , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Fator de Transcrição Sp1/antagonistas & inibidores , ortoaminobenzoatos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Western Blotting , Carcinoma Epitelial do Ovário , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Quimioterapia Combinada , Feminino , Humanos , Proteínas Inibidoras de Apoptose/genética , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Ovarianas/metabolismo , Proteômica/métodos , RNA Mensageiro/genética , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo , Survivina , Células Tumorais CultivadasRESUMO
Overexpression and activation of tyrosine kinase receptors like EGFR and Src regulate the progression and metastasis of Her-2 negative breast cancer. Recently we have reported the role of cell membrane interaction of phospholipid-binding protein annexin A2 (AnxA2) and EGFR in regulating cellular signaling in the activation of angiogenesis, matrix degradation, invasion, and cancer metastasis. Beta-galactoside-specific animal lectin galectin-3 is an apoptosis inhibitor, and cell surface-associated extracellular galectin-3 also has a role in cell migration, cancer progression, and metastasis. Similar expression pattern and membrane co-localization of these two proteins made us to hypothesize in the current study that galectin-3 and AnxA2 interaction is critical for Her-2 negative breast cancer progression. By various experimental analyses, we confirm that glycosylated AnxA2 at the membrane surface interacts with galectin-3. N-linked glycosylation inhibitor tunicamycin treatment convincingly blocked AnxA2 membrane translocation and its association with galectin-3. To analyze whether this interaction has any functional relevance, we tried to dissociate this interaction with purified plant lectin from chickpea (Cicer arietinum agglutinin). This highly specific 30 kDa plant lectin could dissociate AnxA2 from endogenous lectin galectin-3 interaction at the cell surface. This dissociation could down-regulate Bcl-2 family proteins, cell proliferation, and migration simultaneously triggering cell apoptosis. Targeting this interaction of membrane surface glycoprotein and its animal lectin in Her-2 negative breast cancer may be of therapeutic value.
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Anexina A2/metabolismo , Neoplasias da Mama/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Galectina 3/metabolismo , Transdução de Sinais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Genes erbB-2 , Glicosilação , Humanos , Tunicamicina/farmacologiaRESUMO
Breast cancer is known to metastasize in its latter stages of existence. The different angiogenic mechanisms and factors that allow for its progression are reviewed in this article. Understanding these mechanisms and factors will allow researchers to design drugs to inhibit angiogenic behaviors and control the rate of tumor growth.
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Glutamate-induced elevation in intracellular Ca(2+) has been implicated in excitotoxic cell death. Neurons respond to increased glutamate levels by activating an extracellular proteolytic cascade involving the components of the plasmin-plasminogen system. AnxA2 is a Ca(2+)-dependent phospholipid binding protein and serves as an extracellular proteolytic center by recruiting the tissue plasminogen activator and plasminogen and mediating the localized generation of plasmin. Ratiometric Ca(2+) imaging and time-lapse confocal microscopy demonstrated glutamate-induced Ca(2+) influx. We showed that glutamate translocated both endogenous and AnxA2-GFP to the cell surface in a process dependent on the activity of the NMDA receptor. Glutamate-induced translocation of AnxA2 is dependent on the phosphorylation of tyrosine 23 at the N terminus, and mutation of tyrosine 23 to a non-phosphomimetic variant inhibits the translocation process. The cell surface-translocated AnxA2 forms an active plasmin-generating complex, and this activity can be neutralized by a hexapeptide directed against the N terminus. These results suggest an involvement of AnxA2 in potentiating glutamate-induced cell death processes.
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Anexina A2/metabolismo , Ácido Glutâmico/fisiologia , Animais , Anexina A2/química , Anexina A2/genética , Cálcio/metabolismo , Linhagem Celular Transformada , Espaço Extracelular , Fibrinolisina/metabolismo , Proteínas de Fluorescência Verde/genética , Camundongos , Fosforilação , Transporte Proteico , Proteólise , Tirosina/metabolismoRESUMO
BACKGROUND: Migration and invasion enhancer 1 (MIEN1) is a novel gene found to be abundantly expressed in breast tumor tissues and functions as a critical regulator of tumor cell migration and invasion to promote systemic metastases. Previous studies have identified post-translational modifications by isoprenylation at the C-terminal tail of MIEN1 to favor its translocation to the inner leaflet of plasma membrane and its function as a membrane-bound adapter molecule. However, the exact molecular events at the membrane interface activating the MIEN1-driven tumor cell motility are vaguely understood. METHODS: MIEN1 was first studied using in-silico analysis on available RNA sequencing data of human breast tissues and its expression was ascertained in breast cells. We performed several assays including co-immunoprecipitation, wound healing, western blotting and immunofluorescence to decipher the molecular events involved in MIEN1-mediated tumor cell migration. RESULTS: Clinically, MIEN1 is predominantly overexpressed in Her-2 and luminal B subtypes of breast tumors, and its increased expression correlates with poor disease free survival. Molecular studies identified a phosphorylation-dependent activation signal in the immunoreceptor tyrosine based activation motif (ITAM) of MIEN1 and the phosphorylation-deficient MIEN1-mutants (Y39F/50 F) to regulate filopodia generation, migration and invasion. We found that ITAM-phosphorylation of MIEN1 is significantly impaired in isoprenylation-deficient MIEN1 mutants indicating that prenylation of MIEN1 and membrane association is required for cross-phosphorylation of tyrosine residues. Furthermore, we identified MIEN1 as a novel interactor of Annexin A2 (AnxA2), a Ca(2+) -dependent phospholipid binding protein, which serves as an extracellular proteolytic center regulating plasmin generation. Fluorescence resonance energy transfer (FRET) confirmed that MIEN1 physically interacts with AnxA2 and functional studies revealed that they mutually cooperate to accentuate tumor cell motility. Interestingly, our study identified that ectopic overexpression of MIEN1 significantly enhances Tyr23-phosphorylation on AnxA2, thereby stimulating cell surface translocation of AnxA2 and catalyzing the activation of its proteolytic activity. CONCLUSION: Our data show that the presence and interaction of both MIEN1 and AnxA2 in breast tumors are crucial drivers of cell motility. Our study has now deciphered a novel regulatory network governing the vicious process of breast tumor cell invasion-metastasis, and findings suggest MIEN1-AnxA2 as prospective targets to counter the deadly disease.
Assuntos
Anexina A2/genética , Anexina A2/metabolismo , Membrana Celular/metabolismo , Movimento Celular/genética , Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Motivos de Aminoácidos , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Proteínas de Transporte , Linhagem Celular Tumoral , Espaço Extracelular/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Camundongos , Proteínas de Neoplasias/química , Fosforilação , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Processamento de Proteína Pós-Traducional , Transporte Proteico , ProteóliseRESUMO
The Texas Center for Health Disparities, a National Institute on Minority Health and Health Disparities Center of Excellence, presents an annual conference to discuss prevention, awareness education, and ongoing research about health disparities both in Texas and among the national population. The 2014 Annual Texas Conference on Health Disparities brought together experts in research, patient care, and community outreach on the "Role of Genomics in Eliminating Health Disparities." Rapid advances in genomics and pharmacogenomics are leading the field of medicine to use genetics and genetic risk to build personalized or individualized medicine strategies. We are at a critical juncture of ensuring such rapid advances benefit diverse populations. Relatively few forums have been organized around the theme of the role of genomics in eliminating health disparities. The conference consisted of three sessions addressing "Gene-Environment Interactions and Health Disparities," "Personalized Medicine and Elimination of Health Disparities," and "Ethics and Public Policy in the Genomic Era." This article summarizes the basic science, clinical correlates, and public health data presented by the speakers.
RESUMO
Cryptosporidiosis, a gastrointestinal disease caused by protozoans of the genus Cryptosporidium, is a common cause of diarrheal diseases and often fatal in immunocompromised individuals. Bifunctional thymidylate synthase-dihydrofolate reductase (TS-DHFR) from Cryptosporidium hominis (C. hominis) has been a molecular target for inhibitor design. C. hominis TS-DHFR inhibitors with nM potency at a biochemical level have been developed however drug delivery to achieve comparable antiparasitic activity in Cryptosporidium infected cell culture has been a major hurdle for designing effective therapies. Previous mechanistic and structural studies have identified compound 906 as a nM C. hominis TS-DHFR inhibitor in vitro, having µM antiparasitic activity in cell culture. In this work, proof of concept studies are presented using a nanotherapy approach to improve drug delivery and the antiparasitic activity of 906 in cell culture. We utilized PLGA nanoparticles that were loaded with 906 (NP-906) and conjugated with antibodies to the Cryptosporidium specific protein, CP2, on the nanoparticle surface in order to specifically target the parasite. Our results indicate that CP2 labeled NP-906 (CP2-NP-906) reduces the level of parasites by 200-fold in cell culture, while NP-906 resulted in 4.4-fold decrease. Moreover, the anticryptosporidial potency of 906 improved 15 to 78-fold confirming the utility of the antibody conjugated nanoparticles as an effective drug delivery strategy.