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1.
Mol Oncol ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39092562

RESUMO

Metastatic castration-resistant prostate cancer (mCRPC) is characterized by loss of androgen receptor (AR) sensitivity and oncogenic activation of the PI3K/AKT/mTOR (PAM) pathway. Loss of the PI3K regulator PTEN is frequent during prostate cancer (PC) initiation, progression, and therapeutic resistance. Co-targeting the PAM/AR pathways is a promising mCRPC treatment strategy but is hampered by reciprocal negative feedback inhibition or feedback relief. Most PAM inhibitors selectively spare (or weakly inhibit) one or more key nodes of the PAM pathway, potentiating drug resistance depending on the PAM pathway mutation status of patients. We posited that gedatolisib, a uniformly potent inhibitor of all class I PI3K isoforms, as well as mTORC1 and mTORC2, would be more effective than inhibitors targeting single PAM pathway nodes in PC cells. Using a combination of functional and metabolic assays, we evaluated a panel of PC cell lines with different PTEN/PIK3CA status for their sensitivity to multi-node PAM inhibitors (PI3K/mTOR: gedatolisib, samotolisib) and single-node PAM inhibitors (PI3Kα: alpelisib; AKT: capivasertib; mTOR: everolimus). Gedatolisib induced anti-proliferative and cytotoxic effects with greater potency and efficacy relative to the other PAM inhibitors, independent of PTEN/PIK3CA status. The superior effects of gedatolisib were likely associated with more effective inhibition of critical PAM-controlled cell functions, including cell cycle, survival, protein synthesis, oxygen consumption rate, and glycolysis. Our results indicate that potent and simultaneous blockade of all class I PI3K isoforms, mTORC1, and mTORC2 could circumvent PTEN-dependent resistance. Gedatolisib, as a single agent and in combination with other therapies, reported promising preliminary efficacy and safety in various solid tumor types. Gedatolisib is currently being evaluated in a Phase 1/2 clinical trial in combination with darolutamide in patients with mCRPC previously treated with an AR inhibitor, and in a Phase 3 clinical trial in combination with palbociclib and fulvestrant in patients with HR+/HER2- advanced breast cancer.

2.
NPJ Breast Cancer ; 10(1): 40, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839777

RESUMO

The PI3K, AKT, and mTOR (PAM) pathway is frequently dysregulated in breast cancer (BC) to accommodate high catabolic and anabolic activities driving tumor growth. Current therapeutic options for patients with hormone receptor (HR) + / HER2- advanced BC (ABC) include PAM inhibitors that selectively inhibit only one PAM pathway node, which can lead to drug resistance as cells rapidly adapt to maintain viability. We hypothesized that gedatolisib, which potently inhibits all Class I PI3K isoforms, as well as mTORC1 and mTORC2, may be more effective in BC cells than single-node PAM inhibitors by limiting adaptive resistances. By using multiple functional assays, a panel of BC cell lines was evaluated for their sensitivity to four different PAM inhibitors: gedatolisib (pan-PI3K/mTOR inhibitor), alpelisib (PI3Kα inhibitor), capivasertib (AKT inhibitor), and everolimus (mTORC1 inhibitor). Gedatolisib exhibited more potent and efficacious anti-proliferative and cytotoxic effects regardless of the PAM pathway mutational status of the cell lines compared to the single-node PAM inhibitors. The higher efficacy of gedatolisib was confirmed in three-dimensional culture and in BC PDX models. Mechanistically, gedatolisib decreased cell survival, DNA replication, cell migration and invasion, protein synthesis, glucose consumption, lactate production, and oxygen consumption more effectively than the other PAM inhibitors tested. These results indicate that inhibition of multiple PAM pathway nodes by a pan-PI3K/mTOR inhibitor like gedatolisib may be more effective at inducing anti-tumor activity than single-node PAM inhibitors. A global Phase 3 study is currently evaluating gedatolisib plus fulvestrant with and without palbociclib in patients with HR+/HER2- ABC.

3.
Materials (Basel) ; 15(9)2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35591670

RESUMO

Anodic oxidation of CP-Ti, for production of TiO2 nanotubes, has been extensively described in terms of the electrochemical mechanism of tubular growth or the effect of the parameters on the final tube morphology. Recently, a kinetic growth model was proposed to describe the distinct morphologies of the anodic oxide layer as phases of the nanotubular development process, offering a new perspective for the tuning of nanotube production. In this work, the anodizing behavior of a CP-Ti alloy in an ethylene glycol electrolyte was investigated in light of this new model. The final morphology of the nanotubes was characterized by SEM, considering the effects of electrolyte aging, the microstructure, the applied potential difference and time on the morphological development of nanotubes. Electrolyte aging was shown to lead to a decreased dissolution effect on the oxide. The applied potential difference was shown to lead to an increased dissolution effect and more rapid nanotube growth kinetics, while time resulted in extended dissolution. Moreover, the obtained results were analyzed considering a previous study focused on the anodizing behavior of the α- and ß-phases of Ti6Al4V alloy. Overall, the tube morphology resembled that obtained for the Al-containing α-phase of the Ti6Al4V alloy, but the growth kinetics were considerably slower on CP-Ti.

4.
Cancers (Basel) ; 12(8)2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32823855

RESUMO

All-trans retinoic acid (RA), which is the dietary bioactive derivative obtained from animal (retinol) and plant sources (beta-carotene), is a physiological lipid signal of both embryonic and postembryonic development. During pregnancy, either RA deficiency or an excessive RA intake is teratogenic. Too low or too high RA affects not only prenatal, but also postnatal, developmental processes such as myelopoiesis and mammary gland morphogenesis. In this review, we mostly focus on emerging RA-regulated epigenetic mechanisms involving RA receptor alpha (RARA) and Annexin A8 (ANXA8), which is a member of the Annexin family, as well as ANXA8 regulatory microRNAs (miRNAs). The first cancer showing ANXA8 upregulation was reported in acute promyelocytic leukemia (APL), which induces the differentiation arrest of promyelocytes due to defective RA signaling caused by RARA fusion genes as the PML-RARA gene. Over the years, ANXA8 has also been found to be upregulated in other cancers, even in the absence of RARA fusion genes. Mechanistic studies on human mammary cells and mammary glands of mice showed that ANXA8 upregulation is caused by genetic mutations affecting RARA functions. Although not all of the underlying mechanisms of ANXA8 upregulation have been elucidated, the interdependence of RA-RARA and ANXA8 seems to play a relevant role in some normal and tumorigenic settings.

5.
PLoS One ; 15(8): e0237697, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797070

RESUMO

The aim of the project was to investigate the effects of two strategies of teaching new sport actions on performance of eight-year-old children: observational-imitative method (OIM) and descriptive-directive method (DDM). The OIM group was provided with a pre-practice instruction in the form of expert modeling observation by an expert athlete. The DDM group received only verbal explanations of few selected static images. Thirty-six children (18 males and 18 females, mean age = 8,8) participated in the experiment. Subjects were randomly assigned to the OIM or DDM groups. Participants were instructed to perform four sport motor sequences never performed before (shoulder stand, soccer action, vortex howler throw, step action). Actions were videotaped and 2D kinematic analysis performed. A 10-point Likert questionnaire was administered to blind sport experts to assess the correctness and accuracy of each action. Results suggest that the OIM is the most effective instruction method when participants have no experience with the sport action to be performed. On the contrary, if the athlete needs to learn specific aspects of an exercise (such as grasping a tool) the best method is the DDM. In fact, detailed information on how to grab the vortex helped children in throwing it. We also found gender differences which might reflect cultural influences in specific sports (e.g. soccer). Finally, repetition of the exercise also improved the DDM group's performance. This has potential applications in sport teaching, suggesting that in the absence of a model performing the action to be imitated, the DDM can be as effective as the OIM if the observer repeats the sport action many times.


Assuntos
Esportes/educação , Fenômenos Biomecânicos , Criança , Exercício Físico , Feminino , Humanos , Comportamento Imitativo , Aprendizagem , Masculino , Projetos Piloto , Ensino
6.
Cancers (Basel) ; 11(2)2019 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-30678048

RESUMO

Breast ductal carcinoma in situ (DCIS) has been typically recognized by pathologists on the basis of aberrant mammary duct morphology. Thus, there are increasing efforts to detect DCIS biomarkers and druggable targets. In this study we focused on the molecular mechanism involving Annexin A8 (ANXA8), a Ca2+ and phospholipid binding protein, which is regulated by all-trans Retinoic Acid (RA), and it is highly expressed in breast DCIS tissue samples relative to atypical ductal hyperplasia, and normal breast tissue. Using a panel of human mammary epithelial HME1 cell lines that share a common protein signature, and develop in vitro three dimensional (3D) "DCIS-like" amorphous structures, we identified by bioinformatics analysis protein-miRNA pairs, potentially involved in mammary morphogenetic mechanisms, including the ANXA8 mechanism. HME1 cells with genetic mutations hampering the physiological RA regulation of the RA receptor alpha (RARA) transcriptional function, but retain the RARA function controlling the PI3KCA-AKT signaling, develop 3D "DCIS-like" amorphous structures with upregulated ANXA8. Consistently, ectopic ANXA8 expression, by affecting the RARA transcriptional function, induced HME1 DCIS-like amorphous acini expressing phosphorylated AKT (P-AKT). Apparently, a RA-RARA-ANXA8 feedback loop fosters a vicious circle of aberrant morphogenesis. Interestingly, a few miRNAs regulated by RA are predicted to target ANXA8 mRNA. These miRNAs are candidate components of the RA-RARA-ANXA8 mechanism, and their deregulation might induce DCIS initiation.

7.
Oncotarget ; 9(4): 5016-5031, 2018 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-29435159

RESUMO

The MYC transcription factor coordinates, via different RNA polymerases, the transcription of both ribosomal RNA (rRNA) and protein genes necessary for nucleolar as well as mitochondrial ribogenesis. In this study we tested if MYC-coordination of rRNA transcription in the nucleolus and in the mitochondrion drives (cancer) cell proliferation. Here we show that the anti-proliferative effect of CX-5461, a Pol I inhibitor of rRNA transcription, in ovarian (cancer) cell contexts characterized by MYC overexpression is enhanced either by 2'-C-Methyl Adenosine (2'-C-MeA), a ribonucleoside that inhibits POLRMT mitochondrial rRNA (mt-rRNA) transcription and doxycycline, a tetracycline known to affect mitochondrial translation. Thus, hindering not only mt-rRNA transcription, but also mitoribosome function in MYC-overexpressing ovarian (cancer) cells, potentiates the antiproliferative effect of CX-5461. Targeting MYC-regulated rRNA transcription and ribogenesis in both the nucleolus and mitochondrion seems to be a novel approach worth of consideration for treating MYC-driven cancer.

8.
Oncotarget ; 8(49): 85783-85793, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-29156756

RESUMO

RUNX1, a master transcription factor of hematopoiesis, was shown to orchestrate both cell proliferation and differentiation during granulopoiesis by regulating microRNAs (miRs). In this study, taking advantage of the miR-ON reporter system, we monitored first, how the granulocyte colony stimulation factor (GCSF) temporally modulates the concomitant level variation of miR-221 and one of its prototypic targets, the stem cell factor receptor KIT, in single 32DmiR-ON-221 myeloblasts expressing wild type RUNX1. Second, with the same reporter system we assessed how these temporal dynamics are affected by the t(8;21)(q22;q22) acute myelogenous leukemia mutant RUNX1-MTG8 (RM8) in single 32D-RM8miR-ON-221 myeloblasts. Depending on either wild type, or mutant, RUNX1 transcriptional regulation, the cell-context specific miR-221-regulated KIT level translates into differential single cell fate decisions. Collectively, single cell fate choices translate into either initial expansion of undifferentiated myeloblasts followed by terminal granulocyte differentiation, as it happens in normal granulopoiesis, or aggressive growth of undifferentiated myeloblasts, as it happens in RUNX1-MTG8-positive acute myelogenous leukemia. Increasing knowledge of biological changes, due to altered miRNA dynamics, is expected to have relevant translational implications for leukemia detection and treatment.

9.
Oncotarget ; 7(52): 87064-87080, 2016 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-27894085

RESUMO

A hallmark of cancer cells is the ability to evade the growth inhibitory/pro-apoptotic action of physiological all-trans retinoic acid (RA) signal, the bioactive derivative of Vitamin A. However, as we and others reported, RA can also promote cancer cell growth and invasion. Here we show that anticancer and cancer-promoting RA actions in breast cancer have roots in a mechanism of mammary epithelial cell morphogenesis that involves both transcriptional (epigenetic) and non-transcriptional RARα (RARA) functions. We found that the mammary epithelial cell-context specific degree of functionality of the RARA transcriptional (epigenetic) component of this mechanism, by tuning the effects of the non-transcriptional RARA component, determines different cell fate decisions during mammary morphogenesis. Indeed, factors that hamper the RARA epigenetic function make physiological RA drive aberrant morphogenesis via non-transcriptional RARA, thus leading to cell transformation. Remarkably, also the cell context-specific degree of functionality of the RARA epigenetic component retained by breast cancer cells is critical to determine cell fate decisions in response to physiological as well as supraphysiological RA variation. Overall this study supports the proof of principle that the epigenetic functional plasticity of the mammary epithelial cell RARA mechanism, which is essential for normal morphogenetic processes, is necessary to deter breast cancer onset/progression consequent to the insidious action of physiological RA.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Mama/patologia , Epigênese Genética , Receptor alfa de Ácido Retinoico/genética , Tretinoína/farmacologia , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/fisiologia , Feminino , Humanos , Morfogênese , Invasividade Neoplásica , Fosfatidilinositol 3-Quinases/fisiologia
10.
Cell Cycle ; 15(18): 2515-26, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27485818

RESUMO

Upregulation of RNA Polymerase (Pol I)-mediated transcription of rRNA and increased ribogenesis are hallmarks of breast cancer. According to several datasets, including The Cancer Genome Atlas (TCGA), amplification/upregulation of genes encoding for basal components of the Pol I transcriptional machinery is frequent at different breast cancer stages. Here we show that knock down of the RNA polymerase I-specific transcription initiation factor RRN3 (TIF-IA) in breast cancer cells is sufficient to reduce rRNA synthesis and inhibit cell proliferation, and second that stable ectopic expression of RRN3 in human mammary epithelial (HME1) cells, by increasing rRNA transcription, confers increased sensitivity to the anti-proliferative effects of a selective Pol I inhibitor. Further, RRN3-overexpressing HME1 cells, when grown in in vitro 3-dimensional (3D) culture, develop into morphologically aberrant acinar structures lacking a lumen and filled with proliferative cells, thus acquiring a morphology resembling in situ ductal breast cancer lesions (DCIS). Consequently, interference with RRN3 control of Pol I transcription seems capable of both compromising mammary epithelial morphogenetic processes at early breast cancer stages, and driving breast cancer progression by fostering proliferation.


Assuntos
Neoplasias da Mama/enzimologia , Neoplasias da Mama/genética , Células Epiteliais/patologia , Glândulas Mamárias Humanas/patologia , Morfogênese/genética , RNA Polimerase I/genética , Transcrição Gênica , Benzotiazóis/farmacologia , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Genoma Humano , Humanos , Células MCF-7 , Morfogênese/efeitos dos fármacos , Naftiridinas/farmacologia , Invasividade Neoplásica , Proteínas Pol1 do Complexo de Iniciação de Transcrição/genética , Proteínas Pol1 do Complexo de Iniciação de Transcrição/metabolismo , Estabilidade Proteica/efeitos dos fármacos , RNA Ribossômico/genética , Transcrição Gênica/efeitos dos fármacos , Regulação para Cima/genética
11.
Cancer Lett ; 380(2): 375-383, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-27422542

RESUMO

Regardless of the etiological factor, an aberrant morphology is the common hallmark of ductal carcinoma in situ (DCIS), which is a highly heterogeneous disease. To test if critical core morphogenetic mechanisms are compromised by different mutations, we performed proteomics analysis of five mammary epithelial HME1 mutant lines that develop a DCIS-like morphology in three dimensional (3D) culture. Here we show first, that all HME1 mutant lines share a common protein signature highlighting an inverse deregulation of two annexins, ANXA2 and ANXA8. Either ANXA2 downregulation or ANXA8 upregulation in the HME1 cell context are per se sufficient to confer a 3D DCIS-like morphology. Seemingly, different mutations impinged on a common mechanism that differentially regulates the two annexins. Second, we show that ANXA8 expression is significantly higher in DCIS tissue samples versus normal breast tissue and atypical ductal hyperplasia (ADH). Apparently, ANXA8 expression is significantly more upregulated in ER-negative versus ER-positive cases, and significantly correlates with tumor stage, grade and positive lymph node. Based on our study, 3D mammary morphogenesis models can be an alternate/complementary strategy for unraveling new DCIS mechanisms and biomarkers.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Carcinoma Intraductal não Infiltrante/metabolismo , Transformação Celular Neoplásica/metabolismo , Células Epiteliais/metabolismo , Glândulas Mamárias Humanas/metabolismo , Morfogênese , Anexina A2/genética , Anexina A2/metabolismo , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Técnicas de Cultura de Células , Linhagem Celular , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Células Epiteliais/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Genótipo , Humanos , Metástase Linfática , Glândulas Mamárias Humanas/patologia , Mutação , Gradação de Tumores , Estadiamento de Neoplasias , Fenótipo , Proteômica/métodos , Receptores de Estrogênio/metabolismo , Transdução de Sinais , Transfecção
12.
Mol Cancer ; 14: 7, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25612891

RESUMO

BACKGROUND: Core Binding Factor acute myeloid leukemia (CBF-AML) with t(8;21) RUNX1-MTG8 or inv(16) CBFB-MYH11 fusion proteins often show upregulation of wild type or mutated KIT receptor. However, also non-CBF-AML frequently displays upregulated KIT expression. In the first part of this study we show that KIT expression can be also upregulated by miR-17, a regulator of RUNX1, the gene encoding a CBF subunit. Interestingly, both CBF leukemia fusion proteins and miR-17, which targets RUNX1-3'UTR, negatively affect a common core RUNX1-miRNA mechanism that forces myeloid cells into an undifferentiated, KIT-induced, proliferating state. In the second part of this study we took advantage of the conservation of the core RUNX1-miRNA mechanism in mouse and human, to mechanistically demonstrate in a mouse myeloid cell model that increased KIT-induced proliferation is per se a mechanism sufficient to delay myeloid differentiation. METHODS: Human (U937) or mouse (32D) myeloid clonal lines were used, respectively, to test: 1) the effect of RUNX1-MTG8 and CBFB-MYH11 fusion proteins, or upregulation of miR-17, on KIT-induced proliferation and myeloid differentiation, and 2) the effect of upregulation of KIT-induced proliferation per se on myeloid cell differentiation. RESULTS: In the first part of this study we found that stable miR-17 upregulation affects, like the CBF-AML fusion proteins (RUNX1-MTG8 or CBFB-MYH11), a core RUNX1-miRNA mechanism leading to KIT-induced proliferation of differentiation-arrested U937 myeloid cells. In the second part of the study we harnessed the conservation of this core mechanism in human and mouse to demonstrate that the extent of KIT upregulation in 32D mouse myeloid cells with wild type RUNX1 can per se delay G-CSF-induced differentiation. The integrated information gathered from the two myeloid cell models shows that RUNX1 regulates myeloid differentiation not only by direct transcriptional regulation of coding and non-coding myeloid differentiation functions (e.g. miR-223), but also by modulating KIT-induced proliferation via non-coding miRNAs (e.g. miR-221). CONCLUSIONS: The novelty of this study is dual. On the one hand, miRNAs (e.g. miR-17) can mimic the effects of CBF-AML fusion proteins by affecting a core RUNX1-miRNA mechanism of KIT-induced proliferation of undifferentiated myeloid cells. On the other hand, the extent of KIT-induced proliferation itself can modulate myeloid differentiation of cells with wild type RUNX1 function.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/genética , MicroRNAs/genética , Proteínas de Fusão Oncogênica/genética , Interferência de RNA , Regiões 3' não Traduzidas , Animais , Fator de Ligação a CCAAT/genética , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Inversão Cromossômica , Cromossomos Humanos Par 16 , Cromossomos Humanos Par 21 , Cromossomos Humanos Par 8 , Humanos , Leucemia Mieloide Aguda/patologia , Camundongos , Modelos Biológicos , Células Mieloides/metabolismo , Células Mieloides/patologia , Proteínas Proto-Oncogênicas c-kit/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Translocação Genética
13.
Int J Mol Sci ; 14(1): 1566-88, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23344057

RESUMO

Hematopoietic development is orchestrated by gene regulatory networks that progressively induce lineage-specific transcriptional programs. To guarantee the appropriate level of complexity, flexibility, and robustness, these networks rely on transcriptional and post-transcriptional circuits involving both transcription factors (TFs) and microRNAs (miRNAs). The focus of this review is on RUNX1 (AML1), a master hematopoietic transcription factor which is at the center of miRNA circuits necessary for both embryonic and post-natal hematopoiesis. Interference with components of these circuits can perturb RUNX1-controlled coding and non-coding transcriptional programs in leukemia.


Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/genética , Hematopoese/genética , Leucemia/genética , MicroRNAs/genética , Regiões 3' não Traduzidas/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação Leucêmica da Expressão Gênica , Sistema Hematopoético/embriologia , Sistema Hematopoético/crescimento & desenvolvimento , Sistema Hematopoético/metabolismo , Humanos , Modelos Genéticos
14.
Cell Cycle ; 11(19): 3691-700, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-22935699

RESUMO

Altered estrogen receptor α (ERA) signaling and altered circadian rhythms are both features of breast cancer. By using a method to entrain circadian oscillations in human cultured cells, we recently reported that the expression of key clock genes oscillates in a circadian fashion in ERA-positive breast epithelial cells but not in breast cancer cells, regardless of their ERA status. Moreover, we reported that ERA mRNA oscillates in a circadian fashion in ERA-positive breast epithelial cells, but not in ERA-positive breast cancer cells. By using ERA-positive HME1 breast epithelial cells, which can be both entrained in vitro and can form mammary gland-like acinar structures in three-dimensional (3D) culture, first we identified a circuit encompassing ERA and an estrogen-regulated loop consisting of two circadian clock genes, PER2 and BMAL1. Further, we demonstrated that this estrogen-regulated circuit is necessary for breast epithelial acinar morphogenesis. Disruption of this circuit due to ERA-knockdown, negatively affects the estrogen-sustained circadian PER2-BMAL1 mechanism as well as the formation of 3D HME1 acini. Conversely, knockdown of either PER2 or BMAL1, by hampering the PER2-BMAL1 loop of the circadian clock, negatively affects ERA circadian oscillations and 3D breast acinar morphogenesis. To our knowledge, this study provides the first evidence of the implication of an ERA-circadian clock mechanism in the breast acinar morphogenetic process.


Assuntos
Células Acinares/metabolismo , Mama/efeitos dos fármacos , Mama/crescimento & desenvolvimento , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/genética , Estrogênios/farmacologia , Morfogênese/efeitos dos fármacos , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Células Acinares/efeitos dos fármacos , Mama/citologia , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Receptor alfa de Estrogênio/metabolismo , Feminino , Técnicas de Silenciamento de Genes , Humanos , Modelos Biológicos , Morfogênese/genética , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Gênica/efeitos dos fármacos
15.
Eur J Med Chem ; 52: 221-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22483634

RESUMO

Bisphosphonates (BPs) are now the most widely used drugs for diseases associated with increased bone resorption, such as osteoporosis, and tumor bone diseases. A significant drawback of the BPs is their poor oral absorption that is enhanced by the presence of bile acid substituents in the bisphosphonate framework, with no toxic effects. A straightforward synthesis of bile acid-containing hydroxy-bisphosphonates and a full characterization of these pharmaceutically important molecules, including an evaluation of affinity and the mechanism of binding to hydroxyapatite, is presented. The biological activity of bile acid-containing bisphosphonate salts was determined using the neutral-red assay on the L929 cell line and primary cultures of osteoclasts. The bioactivity of the new compounds was found superior than bisphosphonates of established activity.


Assuntos
Ácidos e Sais Biliares/química , Técnicas de Química Sintética , Difosfonatos/síntese química , Difosfonatos/farmacologia , Hidróxidos/química , Absorção , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Difosfonatos/química , Difosfonatos/metabolismo , Durapatita/metabolismo , Trato Gastrointestinal/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos
16.
Cell Cycle ; 11(2): 350-60, 2012 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-22193044

RESUMO

Most physiological and biological processes are regulated by endogenous circadian rhythms under the control of both a master clock, which acts systemically and individual cellular clocks, which act at the single cell level. The cellular clock is based on a network of core clock genes, which drive the circadian expression of non-clock genes involved in many cellular processes. Circadian deregulation of gene expression has emerged to be as important as deregulation of estrogen signaling in breast tumorigenesis. Whether there is a mutual deregulation of circadian and hormone signaling is the question that we address in this study. Here we show that, upon entrainment by serum shock, cultured human mammary epithelial cells maintain an inner circadian oscillator, with key clock genes oscillating in a circadian fashion. In the same cells, the expression of the estrogen receptor α (ER A) gene also oscillates in a circadian fashion. In contrast, ER A-positive and -negative breast cancer epithelial cells show disruption of the inner clock. Further, ER A-positive breast cancer cells do not display circadian oscillation of ER A expression. Our findings suggest that estrogen signaling could be affected not only in ER A-negative breast cancer, but also in ER A-positive breast cancer due to lack of circadian availability of ER A. Entrainment of the inner clock of breast epithelial cells, by taking into consideration the biological time component, provides a novel tool to test mechanistically whether defective circadian mechanisms can affect hormone signaling relevant to breast cancer.


Assuntos
Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/metabolismo , Ritmo Circadiano , Células Epiteliais/fisiologia , Receptor alfa de Estrogênio/metabolismo , Neoplasias da Mama , Linhagem Celular Tumoral , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/genética , Células Epiteliais/metabolismo , Receptor alfa de Estrogênio/genética , Estrogênios/metabolismo , Estrogênios/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Transdução de Sinais , Transcrição Gênica
17.
J Coord Chem ; 63(17): 3016-3027, 2010 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21116471

RESUMO

A new complex salt of composition [Co(phen)(3)](3)(V(4)O(12))(2)Cl·27H(2)O (phen = 1,10-phenanthroline and [V(4)O(12)](4-) = tetrameric dodecaoxotetravanadate ion) was synthesized by reacting appropriate salts in aqueous medium. The complex salt has been characterized by elemental analyses, thermogravimetric analysis (TGA), cyclic voltammetry (CV), FT-IR and UV/Vis spectroscopies, solubility product and conductance measurements. Single crystal X-ray structure determination revealed ionic structure consisting of three complex cations, [Co(phen)(3)](3+), two [V(4)O(12)](4-) anions, one chloride and twenty seven lattice waters. Detailed structural and spectroscopic analyses of [Co(phen)(3)](3)(V(4)O(12))(2)Cl·27H(2)O show that the large anion is stabilized by the large cationic metal complex as there is preferred shape compatibility that leads to a large number of lattice stabilizing non-covalent interactions.

18.
Neoplasia ; 12(11): 866-76, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21076613

RESUMO

Core-binding factor leukemia (CBFL) is a subgroup of acute myeloid leukemia (AML) characterized by genetic mutations involving the subunits of the core-binding factor (CBF). The leukemogenesis model for CBFL posits that one, or more, gene mutations inducing increased cell proliferation and/or inhibition of apoptosis cooperate with CBF mutations for leukemia development. One of the most common mutations associated with CBF mutations involves the KIT receptor. A high expression of KIT is a hallmark of a high proportion of CBFL. Previous studies indicate that microRNA (MIR) 222/221 targets the 3' untranslated region of the KIT messenger RNA and our observation that AML1 can bind the MIR-222/221 promoter, we hypothesized that MIR-222/221 represents the link between CBF and KIT. Here, we show that MIR-222/221 expression is upregulated after myeloid differentiation of normal bone marrow AC133(+) stem progenitor cells. CBFL blasts with either t(8;21) or inv(16) CBF rearrangements with high expression levels of KIT (CD117) display a significantly lower level of MIR-222/221 expression than non-CBFL blasts. Consistently, we found that the t(8;21) AML1-MTG8 fusion protein binds the MIR-222/221 promoter and induces transcriptional repression of a MIR-222/221-LUC reporter. Because of the highly conserved sequence homology, we demonstrated concomitant MIR-222/221 down-regulation and KIT up-regulation in the 32D/WT1 mouse cell model carrying the AML1-MTG16 fusion protein. This study provides the first hint that CBFL-associated fusion proteins may lead to up-regulation of the KIT receptor by down-regulating MIR-222/221, thus explaining the concomitant occurrence of CBF genetic rearrangements and overexpression of wild type or mutant KIT in AML.


Assuntos
Subunidades alfa de Fatores de Ligação ao Core/genética , Leucemia Mieloide/genética , MicroRNAs/genética , Antígeno AC133 , Doença Aguda , Adolescente , Adulto , Idoso , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular Tumoral , Células Cultivadas , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Subunidades alfa de Fatores de Ligação ao Core/metabolismo , Regulação para Baixo , Eritropoetina/farmacologia , Feminino , Citometria de Fluxo , Glicoproteínas/genética , Glicoproteínas/metabolismo , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Humanos , Leucemia Mieloide/metabolismo , Leucemia Mieloide/patologia , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Peptídeos/genética , Peptídeos/metabolismo , Proteínas Proto-Oncogênicas c-kit/genética , Proteínas Proto-Oncogênicas c-kit/metabolismo , Proteína 1 Parceira de Translocação de RUNX1 , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células U937
19.
J Agric Food Chem ; 58(9): 5438-43, 2010 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-20392042

RESUMO

A new approach for removing monoterpenes (MTs) from bergamot oil by selective inclusion in deoxycholic acid (DCA) is proposed. The inclusion process is very efficient, the included fraction being composed mainly of limonene (71.7%) and gamma-terpinene (19.8%). On the other hand, the deterpenated bergamot oil fraction showed for the linalool and linalyl acetate derivatives significant increases from 16.6 and 21.4% to 18.3 and 42.2%, respectively. The major advantages of this methodology are its simplicity, the mild conditions employed, and the quantitative recovery of both host (DCA) and guest (monoterpenes) compounds. Differential scanning calorimetry (DSC), thermal gravimetry (TG), powder X-ray diffractometry (XRPD), infrared spectroscopy (IR), and proton magnetic resonance ((1)H NMR) analysis were used to investigate and characterize the inclusion compounds.


Assuntos
Ácido Desoxicólico/química , Monoterpenos/isolamento & purificação , Óleos de Plantas/química , Varredura Diferencial de Calorimetria , Espectroscopia de Ressonância Magnética , Espectrofotometria Infravermelho , Difração de Raios X
20.
Chem Commun (Camb) ; 46(3): 475-7, 2010 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-20066330

RESUMO

We present the first type of tetraazide-functionalized calix[4]arene TiO(2) nanoparticles and their coupling to propargyl glycosides under Cu(I)-catalysis (click reaction), resulting in the immobilization of calix[4]arene-based glycoclusters on the TiO(2) surface.


Assuntos
Calixarenos/química , Glicosídeos/química , Nanopartículas/química , Fenóis/química , Titânio/química , Alcinos/química , Azidas/química , Catálise , Cobre/química , Nanopartículas/ultraestrutura
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