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1.
Stem Cells ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563224

RESUMO

To resist lineage-dependent therapies such as androgen receptor inhibition, prostate luminal epithelial adenocarcinoma cells often adopt a stem-like state resulting in lineage-plasticity and phenotypic heterogeneity. Castrate resistant prostate adenocarcinoma can transition to neuroendocrine and occasionally to amphicrine, co-expressed luminal and neuroendocrine, phenotypes. We developed CRPC patient-derived organoid models that preserve heterogeneity of the originating tumor, including an amphicrine model displaying a range of luminal and neuroendocrine phenotypes. To gain biological insight and to identify potential treatment targets within heterogeneous tumor cell populations, we assessed the lineage hierarchy and molecular characteristics of various CRPC tumor subpopulations. Transcriptionally similar stem/progenitor cells were identified for all lineage populations. Lineage tracing in amphicrine CRPC showed that heterogeneity originated from distinct subclones of infrequent stem/progenitor cells that produced mainly quiescent differentiated amphicrine progeny. By contrast, adenocarcinoma CRPC progeny originated from stem/progenitor cells and self-renewing differentiated luminal cells. NEPC was composed almost exclusively of self-renewing stem/progenitor cells. Amphicrine subpopulations were enriched for secretory luminal, mesenchymal, and enzalutamide treatment persistent signatures that characterize clinical progression. Finally, the amphicrine stem/progenitor subpopulation was specifically depleted with an AURKA inhibitor, which blocked tumor growth. These data illuminate distinct stem cell characteristics for subtype-specific CRPC in addition to demonstrating a context for targeting differentiation-competent prostate stem cells.

2.
J Clin Invest ; 133(10)2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37183816

RESUMO

Organoid technology has provided new translational research opportunities in oncology, in part by enabling the development of patient-representative living biobanks. Prostate cancer research historically has been constrained to a small number of in vitro models, limiting the ability to translate experimental conclusions for contemporary, heterogeneous patient populations. The facility of organoid culture methods to maintain luminal prostate epithelia, the common lineage of prostate cancers, has greatly expanded the phenotypic and genotypic diversity of available tractable models, including luminal stem/progenitor cells and progressive patient-derived cancers. Biobanks of patient prostate cancer organoids enable increased accuracy in predicting therapeutic efficacy and informative clinical trial designs. Here, we discuss how prostate organoid technology is currently being used, the promising areas of future therapeutic applications, and the current obstacles to be overcome.


Assuntos
Próstata , Neoplasias da Próstata , Masculino , Humanos , Pesquisa Translacional Biomédica , Neoplasias da Próstata/genética , Organoides , Genótipo
4.
Biochim Biophys Acta Mol Basis Dis ; 1864(5 Pt A): 1717-1727, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29477409

RESUMO

The chemokine CC motif ligand 2 (CCL2) is important in recruiting tumor-associated macrophages and is involved in the development of castration-resistance prostate cancer (CRPC) after androgen-deprivation therapy (ADT); however, the underlying mechanism remains unclear. We found that inactivation of the androgen receptor (AR) reduces a transcriptional repressor (SAM pointed domain-containing ETS transcription factor, SPDEF) of CCL2, which mediates epithelial-to-mesenchymal transition (EMT) of prostate tumor cells. Cell lines derived from a prostate-specific Pten/Trp53-null mouse and capable of a spontaneous EMT were utilized for identification of CCL2, and showed that reduced SPDEF expression was associated with an elevated CCL2-activated EMT. AR signaling inhibits CCL2 through a SPDEF-mediated mechanism in that the SPDEF recognizes the CCL2 promoter and transcriptionally represses its activity. Ectopically expressed SPDEF reduced the EMT and rescued expression of CCL2 in SPDEF-expressing cells, which induced the EMT and promotes malignant functions of prostate cancer cells. In tissues from prostate cancer patients with ADT, low SPDEF levels were correlated with high CCL2 expression compared to patients without ADT. We present a novel mechanism that contributes to the EMT and metastatic phenotype observed in a subset of ADT-resistant prostate cancer, where the CCL2 is stimulated through the inactivated of AR-mediated SPDEF.


Assuntos
Androgênios , Quimiocina CCL2/metabolismo , Regulação para Baixo , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica , Neoplasias de Próstata Resistentes à Castração/metabolismo , Proteínas Proto-Oncogênicas c-ets/biossíntese , Animais , Quimiocina CCL2/genética , Masculino , Camundongos , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/terapia , Proteínas Proto-Oncogênicas c-ets/genética
5.
Mol Cancer ; 17(1): 42, 2018 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-29455655

RESUMO

BACKGROUND: ETS variant gene 6 (ETV6) is a putative tumor suppressor and repressed by epidermal growth factor receptor (EGFR) signaling in prostate cancer. Since EGFR antagonists seem ineffective in castration-resistant prostate cancer (CRPC), we aim to study the role of ETV6 in the development of drug resistance. METHODS: Etv6 target gene was validated by ChIP and promoter reporter assays. Correlation of ETV6 and TWIST1 was analyzed in human clinical datasets and tissue samples. Migration, invasion, and metastasis assays were used to measure the cellular responses after perturbation of ETV6 -TWIST1 axis. Proliferation and tumor growth in xenograft model were performed to evaluate the drug sensitivities of EGFR-tyrosine kinase inhibitors (TKIs). RESULTS: ETV6 inhibits TWIST1 expression and disruption of ETV6 promotes TWIST1-dependent malignant phenotypes. Importantly, ETV6 is required to the anti-proliferation effects of EGFR-TKIs, partly due to the inhibitory function of ETV6 on TWIST1. We also found that EGFR-RAS signaling is tightly controlled by ETV6, supporting its role in TKI sensitivity. CONCLUSIONS: Our study demonstrates that disruption of ETV6 contributes to EGFR-TKI resistance, which is likely due to derepression of TWIST1 and activation of EGFR-RAS signaling. Our results implicate ETV6 as a potential marker for predicting efficacy of an EGFR-targeted anticancer approach. Combination treatment of TWIST1 inhibitors could sensitize the anti-proliferation effects of EGFR-TKIs.


Assuntos
Receptores ErbB/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Proto-Oncogênicas c-ets/metabolismo , Proteínas Repressoras/metabolismo , Proteína 1 Relacionada a Twist/metabolismo , Animais , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Humanos , Masculino , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas c-ets/genética , Proteínas Repressoras/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Proteína 1 Relacionada a Twist/genética
6.
Cancer Lett ; 384: 1-8, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27746161

RESUMO

It has been suggested that ETV6 serves as a tumor suppressor; however, its molecular regulation and cellular functions remain unclear. We used prostate cancer as a model system and demonstrated a molecular mechanism in which ETV6 can be regulated by epidermal growth factor receptor (EGFR) signaling through microRNA-96 (miR-96)-mediated downregulation. In addition, EGFR acts as a transcriptional coactivator that binds to the promoter of primary miR-96 and transcriptionally regulates miR-96 levels. We analyzed two sets of clinical prostate cancer samples, confirmed association patterns that were consistent with the EGFR-miR-96-ETV6 signaling model and demonstrated that the reduced ETV6 levels were associated with malignant prostate cancer. Based on results derived from multiple approaches, we identified the biological functions of ETV6 as a tumor suppressor that inhibits proliferation and metastasis in prostate cancer. We present a molecular mechanism in which EGFR activation leads to the induction of miR-96 expression and suppression of ETV6, which contributes to prostate cancer progression.


Assuntos
Neoplasias Ósseas/enzimologia , Movimento Celular , Receptores ErbB/metabolismo , MicroRNAs/metabolismo , Neoplasias da Próstata/enzimologia , Proteínas Proto-Oncogênicas c-ets/metabolismo , Proteínas Repressoras/metabolismo , Transdução de Sinais , Animais , Sítios de Ligação , Neoplasias Ósseas/genética , Neoplasias Ósseas/secundário , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Regulação para Baixo , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Nus , MicroRNAs/genética , Regiões Promotoras Genéticas , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteínas Proto-Oncogênicas c-ets/genética , Interferência de RNA , Estabilidade de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Repressoras/genética , Fatores de Tempo , Transcrição Gênica , Transfecção
7.
Oncotarget ; 7(18): 25726-41, 2016 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-27028864

RESUMO

The SRC kinase has pivotal roles in multiple developmental processes and in tumor progression. An inverse relationship has been observed between androgen receptor (AR) activity and SRC signaling in advanced prostate cancer (PCa); however, the modulation of AR/SRC crosstalk that leads to metastatic PCa is unclear. Here, we showed that patients with high SRC levels displayed correspondingly low canonical AR gene signatures. Our results demonstrated that activated AR induced miR-203 and reduced SRC levels in PCa model systems. miR-203 directly binds to the 3' UTR of SRC and regulates the stability of SRC mRNA upon AR activation. Moreover, we found that progressive PCa cell migration and growth were associated with a decrease in AR-regulated miR-203 and an increase in SRC. Relationships among AR, miR-203, and SRC were also confirmed in clinical datasets and specimens. We suggest that the induction of SRC results in increased PCa metastasis that is linked to the dysregulation of the AR signaling pathway through the inactivation of miR-203.


Assuntos
Regulação Neoplásica da Expressão Gênica/fisiologia , MicroRNAs/metabolismo , Neoplasias da Próstata/patologia , Receptores Androgênicos/metabolismo , Quinases da Família src/metabolismo , Humanos , Masculino , Neoplasias da Próstata/metabolismo
8.
Cell Rep ; 13(10): 2147-58, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26628377

RESUMO

Primary prostate cancer almost always has a luminal phenotype. However, little is known about the stem/progenitor properties of transformed cells within tumors. Using the aggressive Pten/Tp53-null mouse model of prostate cancer, we show that two classes of luminal progenitors exist within a tumor. Not only did tumors contain previously described multipotent progenitors, but also a major population of committed luminal progenitors. Luminal cells, sorted directly from tumors or grown as organoids, initiated tumors of adenocarcinoma or multilineage histological phenotypes, which is consistent with luminal and multipotent differentiation potentials, respectively. Moreover, using organoids we show that the ability of luminal-committed progenitors to self-renew is a tumor-specific property, absent in benign luminal cells. Finally, a significant fraction of luminal progenitors survived in vivo castration. In all, these data reveal two luminal tumor populations with different stem/progenitor cell capacities, providing insight into prostate cancer cells that initiate tumors and can influence treatment response.


Assuntos
Adenocarcinoma/patologia , Células-Tronco Neoplásicas/patologia , Neoplasias da Próstata/patologia , Animais , Linhagem da Célula , Separação Celular , Modelos Animais de Doenças , Células Epiteliais/patologia , Citometria de Fluxo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Organoides , Fenótipo
9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(8): 2231-5, 2015 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-26672300

RESUMO

Three-port tunable optical filter is a key device in the all-optic intelligent switching network and dense wavelength division multiplexing system. The characteristics of the reflecting spectrum, especially the reflectivity and the isolation degree are very important to the three-port filter. Angle-tuned thin film filter is widely used as a three-port tunable filter for its high rectangular degree and good temperature stability. The characteristics of the reflecting spectrum are greatly influenced not only by the incident angle, but also by the wedge angle parameter of the non-paralleled wedge thin film filter. In the present paper, the influences of the wedge angle parameter to the reflectivity and the half bandwidth are analyzed, and the reflecting spectrum characterstics are simulationed in different wedge angle parameter and polarity. The wedge angle-tuned thin film filter with 0.8° wedge angle parameter is fabricated. The experimental results show that keeping the wedge angle the same orientation to the incident angle will worsen the reflectivity and the rectangular degree of the reflecting spectrum. However, keeping the wedge angle orientation reverse to the incident angle will enhance the reflectivity and decrease the bandwidth, which will give higher reflectivity and isolation degree to the three-port filter than that of high parallel degree angle-tuned thin film filter.

10.
Int J Nanomedicine ; 10: 4717-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26251594

RESUMO

Breast cancer is a leading killer of women worldwide. Cyclodextrin-based estrogen receptor-targeting drug-delivery systems represent a promising direction in cancer therapy but have rarely been investigated. To seek new targeting therapies for membrane estrogen receptor-positive breast cancer, an estrogen-anchored cyclodextrin encapsulating a doxorubicin derivative Ada-DOX (CDE1-Ada-DOX) has been synthesized and evaluated in human breast cancer MCF-7 cells. First, we synthesized estrone-conjugated cyclodextrin (CDE1), which formed the complex CDE1-Ada-DOX via molecular recognition with the derivative adamantane-doxorubicin (Ada-DOX) (Kd =1,617 M(-1)). The structure of the targeting vector CDE1 was fully characterized using (1)H- and (13)C-nuclear magnetic resonance, mass spectrometry, and electron microscopy. CDE1-Ada-DOX showed two-phase drug-release kinetics with much slower release than Ada-DOX. The fluorescence polarization analysis reveals that CDE1-Ada-DOX binds to recombinant human estrogen receptor α fragments with a Kd of 0.027 µM. Competition assay of the drug complex with estrogen ligands demonstrated that estrone and tamoxifen competed with CDE1-Ada-DOX for membrane estrogen receptor binding in MCF-7 cells. Intermolecular self-assembly of CDE1 molecules were observed, showing tail-in-bucket and wire-like structures confirmed by transmission electronic microscopy. CDE1-Ada-DOX had an unexpected lower drug uptake (when the host-guest ratio was >1) than non-targeting drugs in MCF-7 cells due to ensconced ligands in cyclodextrins cavities resulting from the intermolecular self-assembly. The uptake of CDE1-Ada-DOX was significantly increased when the host-guest ratio was adjusted to be less than half at the concentration of CDE1 over 5 µM due to the release of the estrone residues. CDE1 elicited rapid activation of mitogen-activated protein kinases (p44/42 MAPK, Erk1/2) in minutes through phosphorylation of Thr202/Tyr204 in MCF-7 cells. These results demonstrate a targeted therapeutics delivery of CDE1-Ada-DOX to breast cancer cells in a controlled manner and that the drug vector CDE1 can potentially be employed as a molecular tool to differentiate nongenomic from genomic mechanism.


Assuntos
Antineoplásicos , Neoplasias da Mama/metabolismo , Ciclodextrinas , Sistemas de Liberação de Medicamentos , Estrogênios , Antineoplásicos/química , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Ciclodextrinas/química , Ciclodextrinas/farmacocinética , Estrogênios/química , Estrogênios/farmacocinética , Feminino , Humanos
11.
Drug Des Devel Ther ; 9: 4441-70, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26300629

RESUMO

Tuberculosis (TB) is still a major public health issue in developing countries, and its chemotherapy is compromised by poor drug compliance and severe side effects. This study aimed to synthesize and characterize new multimodal PEGylated liposomes encapsulated with clinically commonly used anti-TB drugs with linkage to small interfering RNA (siRNA) against transforming growth factor-ß1 (TGF-ß1). The novel NP-siRNA liposomes could target THP-1-derived human macrophages that were the host cells of mycobacterium infection. The biological effects of the NP-siRNA liposomes were evaluated on cell cycle distribution, apoptosis, autophagy, and the gene silencing efficiency of TGF-ß1 siRNA in human macrophages. We also explored the proteomic responses to the newly synthesized NP-siRNA liposomes using the stable isotope labeling with amino acids in cell culture approach. The results showed that the multifunctional PEGylated liposomes were successfully synthesized and chemically characterized with a mean size of 265.1 nm. The novel NP-siRNA liposomes functionalized with the anti-TB drugs and TGF-ß1 siRNA were endocytosed efficiently by human macrophages as visualized by transmission electron microscopy and scanning electron microscopy. Furthermore, the liposomes showed a low cytotoxicity toward human macrophages. There was no significant effect on cell cycle distribution and apoptosis in THP-1-derived macrophages after drug exposure at concentrations ranging from 2.5 to 62.5 µg/mL. Notably, there was a 6.4-fold increase in the autophagy of human macrophages when treated with the NP-siRNA liposomes at 62.5 µg/mL. In addition, the TGF-ß1 and nuclear factor-κB expression levels were downregulated by the NP-siRNA liposomes in THP-1-derived macrophages. The Ingenuity Pathway Analysis data showed that there were over 40 signaling pathways involved in the proteomic responses to NP-siRNA liposome exposure in human macrophages, with 160 proteins mapped. The top five canonical signaling pathways were eukaryotic initiation factor 2 signaling, actin cytoskeleton signaling, remodeling of epithelial adherens junctions, epithelial adherens junction signaling, and Rho GDP-dissociation inhibitor signaling pathways. Collectively, the novel synthetic targeting liposomes represent a promising delivery system for anti-TB drugs to human macrophages with good selectivity and minimal cytotoxicity.


Assuntos
Antituberculosos/administração & dosagem , Sistemas de Liberação de Medicamentos , RNA Interferente Pequeno/administração & dosagem , Fator de Crescimento Transformador beta1/genética , Antituberculosos/farmacologia , Antituberculosos/toxicidade , Apoptose/efeitos dos fármacos , Apoptose/genética , Autofagia/efeitos dos fármacos , Autofagia/genética , Células Cultivadas , Inativação Gênica , Humanos , Lipossomos , Macrófagos/metabolismo , Polietilenoglicóis/química , Proteômica/métodos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Tuberculose/tratamento farmacológico
12.
Cancer Res ; 75(15): 3077-86, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26071255

RESUMO

Dysregulation of the EGFR signaling axis enhances bone metastases in many solid cancers. However, the relevant downstream effector signals in this axis are unclear. miR-1 was recently shown to function as a tumor suppressor in prostate cancer cells, where its expression correlated with reduced metastatic potential. In this study, we demonstrated a role for EGFR translocation in regulating transcription of miR-1-1, which directly targets expression of TWIST1. Consistent with these findings, we observed decreased miR-1 levels that correlated with enhanced expression of activated EGFR and TWIST1 in a cohort of human prostate cancer specimens and additional datasets. Our findings support a model in which nuclear EGFR acts as a transcriptional repressor to constrain the tumor-suppressive role of miR-1 and sustain oncogenic activation of TWIST1, thereby leading to accelerated bone metastasis.


Assuntos
Neoplasias Ósseas/secundário , Receptores ErbB/metabolismo , MicroRNAs/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias da Próstata/patologia , Proteína 1 Relacionada a Twist/metabolismo , Regiões 3' não Traduzidas , Animais , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Receptores ErbB/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos Nus , MicroRNAs/genética , Proteínas Nucleares/genética , Regiões Promotoras Genéticas , Neoplasias da Próstata/genética , Estabilidade de RNA , Proteína 1 Relacionada a Twist/genética , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Drug Des Devel Ther ; 9: 127-46, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25552902

RESUMO

Drug metabolizing enzymes (DMEs) and drug transporters are regulated via epigenetic, transcriptional, posttranscriptional, and translational and posttranslational modifications. Phase I and II DMEs and drug transporters play an important role in the disposition and detoxification of a large number of endogenous and exogenous compounds. The nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a critical regulator of a variety of important cytoprotective genes that are involved in disposition and detoxification of xenobiotics. Schisandra chinensis (SC) is a commonly used traditional Chinese herbal medicine that has been primarily used to protect the liver because of its potent antioxidative and anti-inflammatory activities. SC can modulate some DMEs and drug transporters, but the underlying mechanisms are unclear. In this study, we aimed to explore the role of Nrf2 in the regulatory effect of SC extract (SCE) on selected DMEs and drug transporters in human hepatocellular liver carcinoma cell line (HepG2) cells. The results showed that SCE, schisandrin A, and schisandrin B significantly increased the expression of NAD(P)H: Nicotinamide Adenine Dinucleotide Phosphate-oxidase or:quinone oxidoreductase 1, heme oxygenase-1, glutamate-cysteine ligase, and glutathione S-transferase A4 at both transcriptional and posttranscriptional levels. Incubation of HepG2 cells with SCE resulted in a significant increase in the intracellular level of glutathione and total glutathione S-transferase content. SCE significantly elevated the messenger ribonucleic acid and protein levels of P-glycoprotein and multidrug resistance-associated protein 2 and 4, whereas the expression of organic anion transporting peptide 1A2 and 1B1 was significantly downregulated by SCE. Knockdown of Nrf2 by small interfering ribonucleic acid attenuated the regulatory effect of SCE on these DMEs and drug transporters. SCE significantly upregulated Nrf2 and promoted the translocation of Nrf2 from cytoplasm to the nuclei. Additionally, SCE significantly suppressed the expression of cytosolic Kelch-like ECH-associated protein 1 (the repressor of Nrf2) and remarkably increased Nrf2 stability in HepG2 cells. Taken together, our findings suggest that the hepatoprotective effects of SCE may be partially ascribed to the modulation of DMEs and drug transporters via Nrf2-mediated signaling pathway. SCE may alter the pharmacokinetics of other coadministered drugs that are substrates of these DMEs and transporters and thus cause unfavorable herb-drug interactions.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Preparações Farmacêuticas/metabolismo , Schisandra/química , Transdução de Sinais/efeitos dos fármacos , Transporte Biológico/efeitos dos fármacos , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/isolamento & purificação , Glutamato-Cisteína Ligase/metabolismo , Glutationa Transferase/metabolismo , Heme Oxigenase-1/metabolismo , Células Hep G2 , Humanos , Medicina Tradicional Chinesa , Estrutura Molecular , NAD(P)H Desidrogenase (Quinona)/metabolismo , NADPH Oxidase 4 , NADPH Oxidases/metabolismo , Relação Estrutura-Atividade , Células Tumorais Cultivadas
14.
Oncotarget ; 6(1): 441-57, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25436980

RESUMO

Aberrant activation of Ras and WNT signaling are key events that have been shown to be up-regulated in prostate cancer that has metastasized to the bone. However, the regulatory mechanism of combinatorial Ras and WNT signaling in advanced prostate cancer is still unclear. TCF7, a WNT signaling-related gene, has been implicated as a critical factor in bone metastasis, and here we show that TCF7 is a direct target of miR-34a. In samples of prostate cancer patients, miR-34a levels are inversely correlated with TCF7 expression and a WNT dependent gene signature. Ectopic miR-34a expression inhibited bone metastasis and reduced cancer cell proliferation in a Ras-dependent xenograft model. We demonstrate that miR-34a can directly interfere with the gene expression of the anti-proliferative BIRC5, by targeting BIRC5 3'UTR. Importantly, BIRC5 overexpression was sufficient to reconstitute anti-apoptotic signaling in cells expressing high levels of miR-34a. In prostate cancer patients, we found that BIRC5 levels were positively correlated with a Ras signaling signature expression. Our data show that the bone metastasis and anti-apoptotic effects found in Ras signaling-activated prostate cancer cells require miR-34a deficiency, which in turn aids in cell survival by activating the WNT and anti-apoptotic signaling pathways thereby inducing TCF7 and BIRC5 expressions.


Assuntos
Neoplasias Ósseas/secundário , Regulação Neoplásica da Expressão Gênica/genética , MicroRNAs/metabolismo , Neoplasias da Próstata/patologia , Transdução de Sinais , Fator 1 de Transcrição de Linfócitos T/metabolismo , Animais , Western Blotting , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Imuno-Histoquímica , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Masculino , Camundongos , Camundongos Nus , MicroRNAs/genética , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Reação em Cadeia da Polimerase , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Transdução de Sinais/fisiologia , Survivina , Fator 1 de Transcrição de Linfócitos T/genética , Transfecção , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteínas ras/genética , Proteínas ras/metabolismo
15.
Oncotarget ; 5(11): 3770-84, 2014 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25004126

RESUMO

Activation of EGFR signaling pathway leads to prostate cancer bone metastasis; however, therapies targeting EGFR have demonstrated limited effectiveness and led to drug resistance. miR-203 levels are down-regulated in clinical samples of primary prostate cancer and further reduced in metastatic prostate cancer. Here we show that ectopic miR-203 expression displayed reduced bone metastasis and induced sensitivity to tyrosine kinase inhibitors (TKIs) treatment in a xenograft model. Our results demonstrate that the induction of bone metastasis and TKI resistance require miR-203 down regulation, activation of the EGFR pathway via altered expression of EGFR ligands (EREG and TGFA) and anti-apoptotic proteins (API5, BIRC2, and TRIAP1). Importantly, a sufficient reconstitution of invasiveness and resistance to TKIs treatment was observed in cells transfected with anti-miR-203. In prostate cancer patients, our data showed that miR-203 levels were inversely correlated with the expression of two EGFR ligands, EREG and TGFA, and an EGFR dependent gene signature. Our results support the existence of a miR-203, EGFR, TKIs resistance regulatory network in prostate cancer progression. We propose that the loss of miR-203 is a molecular link in the progression of prostate cancer metastasis and TKIs resistance characterized by high EGFR ligands output and anti-apoptotic proteins activation.


Assuntos
Neoplasias Ósseas/secundário , Receptores ErbB/metabolismo , MicroRNAs/metabolismo , Neoplasias da Próstata/patologia , Regiões 3' não Traduzidas , Anfirregulina , Animais , Sequência de Bases , Neoplasias Ósseas/enzimologia , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Regulação para Baixo , Família de Proteínas EGF/genética , Família de Proteínas EGF/metabolismo , Epirregulina/genética , Epirregulina/metabolismo , Receptores ErbB/antagonistas & inibidores , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Nus , MicroRNAs/biossíntese , MicroRNAs/genética , Dados de Sequência Molecular , Metástase Neoplásica , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Transdução de Sinais , Fator de Crescimento Transformador alfa/genética , Fator de Crescimento Transformador alfa/metabolismo , Proteínas ras/biossíntese , Proteínas ras/genética , Proteínas ras/metabolismo
16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(8): 2290-3, 2013 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-24159896

RESUMO

Angle-tuned thin film filter is widely used in the DWDM system for its broad tunable wavelength range and high rectangular degree. The transmissivity and the half bandwidth is greatly influenced not only by the incident angle, but also by the wedge angle of the non-paralleled thin film filter. In the present paper, the influences of the wedge angle on the transmissivity and the half bandwidth were detailedly analyzed. The proper wedge angle and the orientation can greatly improve the characteristics of the transmittance spectrum. The angle-tuned thin film filter with 0.8 degrees wedge angle was also fabricated. The experimental results show that keeping the wedge angle with the same orientation to the incident angle will worsen the transmissivity and the rectangular degree of the transmittance spectrum. However, keeping the wedge angle orientation reverse to the incident angle will greatly enhance the transmissivity and the rectangular degree of the filter and its tunable wavelength range will broaden by 10 nm.

17.
PLoS One ; 8(5): e62289, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23658721

RESUMO

Drug targeting is an active area of research and nano-scaled drug delivery systems hold tremendous potential for the treatment of neoplasms. In this study, a novel cyclodextrin (CD)-based nanoparticle drug delivery system has been assembled and characterized for the therapy of folate receptor-positive [FR(+)] cancer. Water-soluble folic acid (FA)-conjugated CD carriers (FACDs) were successfully synthesized and their structures were confirmed by 1D/2D nuclear magnetic resonance (NMR), matrix-assisted laser desorption ionization time-of-flight mass spectrometer (MALDI-TOF-MS), high performance liquid chromatography (HPLC), Fourier transform infrared spectroscopy (FTIR), and circular dichroism. Drug complexes of adamatane (Ada) and cytotoxic doxorubicin (Dox) with FACD were readily obtained by mixed solvent precipitation. The average size of FACD-Ada-Dox was 1.5-2.5 nm. The host-guest association constant K a was 1,639 M(-1) as determined by induced circular dichroism and the hydrophilicity of the FACDs was greatly enhanced compared to unmodified CD. Cellular uptake and FR binding competitive experiments demonstrated an efficient and preferentially targeted delivery of Dox into FR-positive tumor cells and a sustained drug release profile was seen in vitro. The delivery of Dox into FR(+) cancer cells via endocytosis was observed by confocal microscopy and drug uptake of the targeted nanoparticles was 8-fold greater than that of non-targeted drug complexes. Our docking results suggest that FA, FACD and FACD-Ada-Dox could bind human hedgehog interacting protein that contains a FR domain. Mouse cardiomyocytes as well as fibroblast treated with FACD-Ada-Dox had significantly lower levels of reactive oxygen species, with increased content of glutathione and glutathione peroxidase activity, indicating a reduced potential for Dox-induced cardiotoxicity. These results indicate that the targeted drug complex possesses high drug association and sustained drug release properties with good biocompatibility and physiological stability. The novel FA-conjugated ß-CD based drug complex might be promising as an anti-tumor treatment for FR(+) cancer.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/síntese química , Transportadores de Ácido Fólico/metabolismo , beta-Ciclodextrinas/química , Amidas/química , Animais , Antineoplásicos/efeitos adversos , Transporte Biológico , Linhagem Celular Tumoral , Técnicas de Química Sintética , Doxorrubicina/efeitos adversos , Doxorrubicina/metabolismo , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Ácido Fólico/química , Ácido Fólico/metabolismo , Transportadores de Ácido Fólico/química , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Tamanho da Partícula , Conformação Proteica , Espécies Reativas de Oxigênio/metabolismo
18.
Zhong Yao Cai ; 36(6): 953-8, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-24380284

RESUMO

OBJECTIVE: To investigate the effect of Chinese herbal medicine with Supplement Qi and Activating Blood Circulation (huangqi and danshen) on urinary protein, kidney function and tubular reabsorption of diabetic nephropathy rats. METHODS: SD rats were randomly divided into a nondiabetic control group (normal group) and three groups in which diabetes were induced by a single intraperitoneal injection of freshly prepared streptozotocin( STZ,55 mg/kg body weight). Then the diabetes rats were randomly assigned to three groups: diabetic model group, Supplement Qi and Activating Blood Circulation traditional Chinese medicine group (huangqi and danshen group) and Gliquidone group (as a reference hypoglycemic drug). Each group was treated with corresponding drugs for 6 weeks. At the end of the study, the rats from each group were injected with FITC-labeled BSA through tail vein. The 24 h urinary protein excretion were measured and blood was collected for measuring plasma glucose levels, serum creatinine (Cr), blood urea nitrogen (BUN), triglyceride (TG) and total cholesterol (T-CHO). Renal tissue was used to measure the level of LPO,SOD,GSH-Px and AGEs and Paraffin-embedded sections were stained with HE, PAS and immunohistochemistry. RESULTS: The plasma glucose, the 24 h urinary protein excretion, the levels of serum Cr, BUN, TG and T-CHO in STZ-induced diabetic rats were higher than those of nondiabetic rats. Diabetic rats showed significantly increase in LPO and AGEs (P < 0.01) and decrease in antioxidant enzyme activity (both GSH-Px and SOD) (P < 0.05) as compared with non-diabetic control rats. Treatment with the Supplement Qi and Activating Blood Circulation traditional Chinese medicine for 6 weeks in diabetic rats significantly reduced the 24 h urinary protein excretion compared with model control (P < 0.01), and markedly decreased the levels of serum Cr,BUN,TG and T-CHO as compared with those of diabetic rat (P < 0.05). The levels of LPO and AGEs were decreased and the activity of GSH-Px was increased by Supplement Qi and Activating Blood Circulation treatment. The kidney proximal tubule lesions were improved and the reabsorption of FITC-BSA in tubular was increased in diabetic rats treated by huangqi and danshen, and the expression of megalin in proximal tubular was enhanced as compared with diabetic rats. CONCLUSION: Diabetic nephropathy rats treated with traditional Chinese medicine therapeutic principles "Supplement Qi and Activating Blood Circulation" can reduce the 24 h urinary protein excretion and improve the function of tubular reabsorption. These protect effects may be in correlation with enhancement the renal tissue activity of antioxidant and up-regulation the expression of megalin in renal tubular epithelial cells in diabetic rats.


Assuntos
Nefropatias Diabéticas/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Túbulos Renais/efeitos dos fármacos , Proteína-2 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Absorção/efeitos dos fármacos , Animais , Astragalus propinquus/química , Biomarcadores/sangue , Biomarcadores/urina , Glicemia/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/fisiopatologia , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/administração & dosagem , Testes de Função Renal , Túbulos Renais/metabolismo , Túbulos Renais/fisiopatologia , Masculino , Fitoterapia/métodos , Ratos , Ratos Sprague-Dawley , Salvia miltiorrhiza/química , Estreptozocina
19.
Drug Deliv Transl Res ; 3(4): 364-74, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25788282

RESUMO

The efficacy and applicability of anticancer drugs are greatly restricted by severe systemic toxicities and drug resistance. Targeting drug delivery strategies have been developed to prevent the shortcomings of chemotherapy. Among various approaches to specifically target drug-loaded carrier systems to the required pathological sites, ligand-attached cyclodextrin-based targeting complexes are a promising drug delivery system, which is achieved mainly through specific molecular interactions between the drugs and cell surface receptors. The principal targeting tactics include conjugation of cyclodextrin with targeting moieties or encapsulation drugs in cyclodextrins. The cyclodextrin-based supramolecules, polymers, or nanoparticles bearing bioactive substances such as folate, estrogens, carbohydrates, peptides, etc. have been reviewed.

20.
Cancer Res ; 72(23): 6247-56, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23002206

RESUMO

TGF-ß derived from bone fuels melanoma bone metastases by inducing tumor secretion of prometastatic factors that act on bone cells to change the skeletal microenvironment. Halofuginone is a plant alkaloid derivative that blocks TGF-ß signaling with antiangiogenic and antiproliferative properties. Here, we show for the first time that halofuginone therapy decreases development and progression of bone metastasis caused by melanoma cells through the inhibition of TGF-ß signaling. Halofuginone treatment of human melanoma cells inhibited cell proliferation, phosphorylation of SMAD proteins in response to TGF-ß, and TGF-ß-induced SMAD-driven transcription. In addition, halofuginone reduced expression of TGF-ß target genes that enhance bone metastases, including PTHrP, CTGF, CXCR4, and IL11. Also, cell apoptosis was increased in response to halofuginone. In nude mice inoculated with 1205 Lu melanoma cells, a preventive protocol with halofuginone inhibited bone metastasis. The beneficial effects of halofuginone treatment were comparable with those observed with other anti-TGF-ß strategies, including systemic administration of SD208, a small-molecule inhibitor of TGF-ß receptor I kinase, or forced overexpression of Smad7, a negative regulator of TGF-ß signaling. Furthermore, mice with established bone metastases treated with halofuginone had significantly less osteolysis than mice receiving placebo assessed by radiography. Thus, halofuginone is also effective in reducing the progression of melanoma bone metastases. Moreover, halofuginone treatment reduced melanoma metastasis to the brain, showing the potential of this novel treatment against cancer metastasis.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Ósseas/prevenção & controle , Neoplasias Ósseas/secundário , Melanoma/tratamento farmacológico , Piperidinas/farmacologia , Quinazolinonas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/metabolismo , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Expressão Gênica , Humanos , Melanoma/metabolismo , Melanoma/patologia , Melanoma/secundário , Camundongos , Camundongos Nus , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
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