Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Adv Sci (Weinh) ; 10(33): e2305096, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37845006

RESUMO

Despite advances in precision oncology, cancer remains a global public health issue. In this report, proof-of-principle evidence is presented that a cell-penetrable peptide (ACP52C) dissociates transcription factor CP2c complexes and induces apoptosis in most CP2c oncogene-addicted cancer cells through transcription activity-independent mechanisms. CP2cs dissociated from complexes directly interact with and degrade YY1, leading to apoptosis via the MDM2-p53 pathway. The liberated CP2cs also inhibit TDP2, causing intrinsic genome-wide DNA strand breaks and subsequent catastrophic DNA damage responses. These two mechanisms are independent of cancer driver mutations but are hindered by high MDM2 p60 expression. However, resistance to ACP52C mediated by MDM2 p60 can be sensitized by CASP2 inhibition. Additionally, derivatives of ACP52C conjugated with fatty acid alone or with a CASP2 inhibiting peptide show improved pharmacokinetics and reduced cancer burden, even in ACP52C-resistant cancers. This study enhances the understanding of ACP52C-induced cancer-specific apoptosis induction and supports the use of ACP52C in anticancer drug development.


Assuntos
Proteínas de Ligação a DNA , Neoplasias , Humanos , Proteínas de Ligação a DNA/genética , Neoplasias/genética , Mutações Sintéticas Letais , Medicina de Precisão , Fatores de Transcrição/genética , Peptídeos , Diester Fosfórico Hidrolases/genética
2.
Cancers (Basel) ; 15(13)2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37444605

RESUMO

Yin Yang 1 (YY1) is a transcription factor that regulates epigenetic pathways and protein modifications. CP2c is a transcription factor that functions as an oncogene to regulate cell proliferation. YY1 is known to interact with CP2c to suppress CP2c's transcriptional activity. This study aimed to investigate YY1 and CP2c expression in breast cancer and prognostic implications. In this study, YY1 and CP2c expression was evaluated using immunohistochemical staining, Western blot and RT-PCR assays. Of 491 patients with primary breast cancer, 138 patients showed YY1 overexpression. Luminal subtype and early stage were associated with overexpression (p < 0.001). After a median follow-up of 68 months, YY1 overexpression was found to be associated with a better prognosis (disease-free survival rates of 92.0% vs. 79.2%, p = 0.014). In Cox proportional hazards model, YY1 overexpression functioned as an independent prognostic factor after adjustment of hormone receptor/HER2 status and tumor size (hazard ratio of 0.50, 95% CI 0.26-0.98, p = 0.042). Quantitative analysis of YY1 and CP2c protein expression in tumors revealed a negative correlation between them. In conclusion, YY1 overexpression is a favorable prognostic biomarker in patients with breast cancer, and it has a negative correlation with CP2c at the protein level.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 298: 122769, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37163900

RESUMO

We present the application of the recently implemented nuclear velocity perturbation theory, using the combined Gaussian and plane waves approach in CP2K, to the vibrational circular dichroism (VCD) spectra of a set of natural products. Even though the calculations were carried out for isolated molecules in the gas-phase limit, neglecting inter-molecular interactions and anharmonic effects, the match between simulated and experimental spectra is reasonable. We also study the influence of different density functionals on the conformational search and the resulting VCD spectra via group coupling matrices (GCMs). The GCM analysis reveals that the VCD signal can in some cases arise from moieties which are close to each other and in other cases from moieties far from each other. Differences in spectra obtained using different exchange-correlation density functionals can be attributed to interaction terms between different moieties in the molecules changing their sign.

4.
Int J Mol Sci ; 23(12)2022 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-35742810

RESUMO

CP2c, also known as TFCP2, α-CP2, LSF, and LBP-1c, is a prototypic member of the transcription factor (TF) CP2 subfamily involved in diverse ubiquitous and tissue/stage-specific cellular processes and in human malignancies including cancer. Despite its importance, many fundamental regulatory mechanisms of CP2c are still unclear. Here, we uncover unprecedented structural and functional aspects of CP2c using DSP crosslinking and Western blot in addition to conventional methods. We found that a monomeric form of a CP2c homotetramer (tCP2c; [C4]) binds to the known CP2c-binding DNA motif (CNRG-N(5~6)-CNRG), whereas a dimeric form of a CP2c, CP2b, and PIAS1 heterohexamer ([C2B2P2]2) binds to the three consecutive CP2c half-sites or two staggered CP2c binding motifs, where the [C4] exerts a pioneering function for recruiting the [C2B2P2]2 to the target. All CP2c exists as a [C4], or as a [C2B2P2]2 or [C2B2P2]4 in the nucleus. Importantly, one additional cytosolic heterotetrameric CP2c and CP2a complex, ([C2A2]), exerts some homeostatic regulation of the nuclear complexes. These data indicate that these findings are essential for the transcriptional regulation of CP2c in cells within relevant timescales, providing clues not only for the transcriptional regulation mechanism by CP2c but also for future therapeutics targeting CP2c function.


Assuntos
Proteínas de Ligação a DNA , Fatores de Transcrição , Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Humanos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
5.
Acta Pharm Sin B ; 12(2): 483-495, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35256930

RESUMO

Alzheimer's disease (AD), the most prominent form of dementia in the elderly, has no cure. Strategies focused on the reduction of amyloid beta or hyperphosphorylated Tau protein have largely failed in clinical trials. Novel therapeutic targets and strategies are urgently needed. Emerging data suggest that in response to environmental stress, mitochondria initiate an integrated stress response (ISR) shown to be beneficial for healthy aging and neuroprotection. Here, we review data that implicate mitochondrial electron transport complexes involved in oxidative phosphorylation as a hub for small molecule-targeted therapeutics that could induce beneficial mitochondrial ISR. Specifically, partial inhibition of mitochondrial complex I has been exploited as a novel strategy for multiple human conditions, including AD, with several small molecules being tested in clinical trials. We discuss current understanding of the molecular mechanisms involved in this counterintuitive approach. Since this strategy has also been shown to enhance health and life span, the development of safe and efficacious complex I inhibitors could promote healthy aging, delaying the onset of age-related neurodegenerative diseases.

6.
J Exp Clin Cancer Res ; 41(1): 73, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35193647

RESUMO

BACKGROUND: Integrin alpha 2 (ITGA2) has been recently reported to be an oncogene and to play crucial roles in tumor cell proliferation, invasion, metastasis, and angiogenesis. Our previous study showed that ITGA2 was overexpressed in pancreatic cancer and promoted its progression. However, the mechanism of ITGA2 overexpression and other mechanisms for promoting the progression of pancreatic cancer are still unclear. METHODS: The GEPIA database was used to confirm the expression of ITGA2 in pancreatic cancer. To verify the influence of ITGA2 and TGF-ß on the morphological changes of pancreatic cancer and tumor cell progression, we conduct CCK8 test, plate cloning, flow cytometry experiments and animal experiments. Then we conduct Western blot, RT-qPCR to explore the relationship between ITGA2 and TGF-ß, and then find the key molecules which can regulate them by immunoprecipitation, Western blot, RT-qPCR, CHIP, nuclear and cytoplasmic separation test. RESULTS: The results of the present study show that the abnormal activation of KRAS induced the overexpression of ITGA2 in pancreatic cancer. Moreover, ITGA2 expression significantly suppressed the activation of the TGF-ß pathway. ITGA2 silencing enhanced the anti-pancreatic cancer proliferation and tumor growth effects of TGF-ß. Mechanistically, ITGA2 expression suppressed the activation of the TGF-ß pathway by inhibiting the SMAD2 expression transcriptionally. In addition, it interacted with and inhibited the nuclear translocation of TFCP2, which induced the SMAD2 expression as a transcription factor. Furthermore, TFCP2 also induced ITGA2 expression as a transcription factor, and the TFCP2 feedback regulated the ITGA2-TFCP2-SMAD2 pathway. CONCLUSIONS: Taken together, these results indicated that ITGA2 expression could inhibit the activation of the TGF-ß signaling pathway in pancreatic cancer via the TFCP2-SMAD2 axis. Therefore, ITGA2, by effectively enhancing the anti-cancer effects of TGF- ß, might be a potential clinical therapeutic target for pancreatic cancer.


Assuntos
Adenocarcinoma/genética , Carcinoma Ductal Pancreático/genética , Integrina alfa2/metabolismo , Oncogenes/genética , Proteína Smad2/metabolismo , Fatores de Transcrição/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Adenocarcinoma/patologia , Animais , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Transdução de Sinais
7.
Endocr J ; 68(8): 1011-1025, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34092745

RESUMO

Circular RNAs (circRNAs) are correlated with the occurrence and progression of differentiated thyroid cancer (THCA). However, the regulatory mechanism of circRNAs in differentiated THCA is unclear. In the present study, we analyzed the circRNA microarray dataset (GSE93522) of thyroid tumors and discovered that circRNA HACE1 (circHACE1) was downregulated in differentiated THCA. We detected circHACE1 expression by quantitative real-time polymerase chain reaction (qRT-PCR). Gain-of-function experiments were performed to analyze the biological function of circHACE1 in differentiated THCA cells in vitro. The regulatory mechanism of circHACE1 in differentiated THCA was explored through bioinformatics analysis, dual-luciferase reporter, RIP (RNA immunoprecipitation), and/or RNA pull-down assays. The biological function of circHACE1 in THCA was confirmed by xenograft assay. We verified that circHACE1 was downregulated in differentiated THCA. Also, differentiated THCA patients with low circHACE1 expression were associated with TNM grade, lymphoid node metastasis, tumor size, and poor prognosis. CircHACE1 overexpression decreased xenograft tumor growth in vivo and induced cell cycle arrest, apoptosis, impeded proliferation, migration, and invasion in differentiated THCA cells in vitro. CircHACE1 could function as a microRNA (miR)-346 sponge and regulated Tfcp2L1 (transcription factor CP2 like 1) expression. MiR-346 overexpression offset circHACE1 elevation-mediated effects on malignant behaviors of differentiated THCA cells. Furthermore, Tfcp2L1 silencing counteracted the suppressive impact of miR-346 inhibitor on the malignancy of differentiated THCA cells. In conclusion, circHACE1 adsorbed miR-346 and elevated Tfcp2L1 expression, thus curbing cell malignancy in differentiated THCA, manifesting that circHACE1 might be a target for differentiated THCA treatment.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , RNA Circular/genética , Proteínas Repressoras/genética , Neoplasias da Glândula Tireoide/genética , Adulto , Apoptose/genética , Pontos de Checagem do Ciclo Celular/genética , Proliferação de Células/genética , Progressão da Doença , Feminino , Humanos , Masculino , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Prognóstico , RNA Circular/metabolismo , Proteínas Repressoras/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Regulação para Cima
8.
Chem Asian J ; 16(7): 753-756, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33638240

RESUMO

The total synthesis of panaginsene has been accomplished in 11 linear steps starting from methyl 3,3-dimethyl-5-oxocyclopent-1-ene-1-carboxylate. The key steps are a Sharpless asymmetric epoxidation and Ti(III)-mediated reductive epoxide opening-radical cyclization to construct the chiral quaternary carbon stereocenter followed by a very challenging HWE olefination reaction on an 1,3-keto aldehyde and a late stage McMurry olefination using low valent titanium to construct the highly constrained angular tetrasubstituted olefin in a five-membered ring.

9.
J Cancer Res Clin Oncol ; 147(3): 755-765, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33315124

RESUMO

PURPOSE: The transcription factors YY1 and CP2 have been associated with tumor promotion and suppression in various cancers. Recently, simultaneous expression of both markers was correlated with negative prognosis in cancer. The aim of this study was to explore the expression of YY1 and CP2 in head and neck squamous cell carcinoma (HNSCC) patients and their association with survival. METHODS: First, we analyzed mRNA expression and copy number variations (CNVs) of YY1 and CP2 using "The Cancer Genome Atlas" (TCGA) with 510 HNSCC patients. Secondly, protein expression was investigated via immunohistochemistry in 102 patients, who were treated in the Vienna General Hospital, utilizing a tissue microarray. RESULTS: The median follow-up was 2.9 years (1.8-4.6) for the TCGA cohort and 10.3 years (6.5-12.8) for the inhouse tissue micro-array (TMA) cohort. The median overall survival of the TCGA cohort was decreased for patients with a high YY1 mRNA expression (4.0 vs. 5.7 years, p = 0.030, corr. p = 0.180) and high YY1-CNV (3.53 vs. 5.4 years, p = 0.0355, corr. p = 0.213). Furthermore, patients with a combined high expression of YY1 and CP2 mRNA showed a worse survival (3.5 vs. 5.4 years, p = 0.003, corr. p = 0.018). The mortality rate of patients with co-expression of YY1 and CP2 mRNA was twice as high compared to patients with low expression of one or both (HR 1.99, 95% CI 1.11-3.58, p = 0.021). Protein expression of nuclear YY1 and CP2 showed no association with disease outcome in our inhouse cohort. CONCLUSION: Our data indicate that simultaneous expression of YY1 and CP2 mRNA is associated with shorter overall survival. Thus, combined high mRNA expression might be a suitable prognostic marker for risk stratification in HNSCC patients. However, since we could not validate this finding at genomic or protein level, we hypothesize that unknown underlying mechanisms which regulate mRNA transcription of YY1 and CP2 are the actual culprits leading to a worse survival.


Assuntos
Proteínas de Ligação a DNA/genética , Neoplasias de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Fatores de Transcrição/genética , Fator de Transcrição YY1/genética , Biomarcadores Tumorais , Proteínas de Ligação a DNA/biossíntese , Bases de Dados Genéticas , Feminino , Dosagem de Genes , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Análise Serial de Tecidos , Fatores de Transcrição/biossíntese , Fator de Transcrição YY1/biossíntese
10.
J Biol Chem ; 295(14): 4748-4759, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32111740

RESUMO

Microtubules are cytoskeletal structures critical for mitosis, cell motility, and protein and organelle transport and are a validated target for anticancer drugs. However, how tubulins are regulated and recruited to support these distinct cellular processes is incompletely understood. Posttranslational modifications of tubulins are proposed to regulate microtubule function and dynamics. Although many of these modifications have been investigated, only one prior study reports tubulin methylation and an enzyme responsible for this methylation. Here we used in vitro radiolabeling, MS, and immunoblotting approaches to monitor protein methylation and immunoprecipitation, immunofluorescence, and pulldown approaches to measure protein-protein interactions. We demonstrate that N-lysine methyltransferase 5A (KMT5A or SET8/PR-Set7), which methylates lysine 20 in histone H4, bound α-tubulin and methylated it at a specific lysine residue, Lys311 Furthermore, late SV40 factor (LSF)/CP2, a known transcription factor, bound both α-tubulin and SET8 and enhanced SET8-mediated α-tubulin methylation in vitro In addition, we found that the ability of LSF to facilitate this methylation is countered by factor quinolinone inhibitor 1 (FQI1), a specific small-molecule inhibitor of LSF. These findings suggest the general model that microtubule-associated proteins, including transcription factors, recruit or stimulate protein-modifying enzymes to target tubulins. Moreover, our results point to dual functions for SET8 and LSF not only in chromatin regulation but also in cytoskeletal modification.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Fatores de Transcrição/metabolismo , Tubulina (Proteína)/metabolismo , Animais , Células COS , Chlorocebus aethiops , Proteínas de Ligação a DNA/genética , Células HEK293 , Histona-Lisina N-Metiltransferase/genética , Histonas/metabolismo , Humanos , Metilação , Ligação Proteica , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Fatores de Transcrição/genética
11.
Dev Reprod ; 24(4): 249-262, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33537512

RESUMO

Spermatogonial stem cells (SSCs) have stemness characteristics, including germ cell-specific imprints that allow them to form gametes. Spermatogenesis involves changes in gene expression such as a transition from expression of somatic to germ cell-specific genes, global repression of gene expression, meiotic sex chromosome inactivation, highly condensed packing of the nucleus with protamines, and morphogenesis. These step-by-step processes finally generate spermatozoa that are fertilization competent. Dynamic epigenetic modifications also confer totipotency to germ cells after fertilization. Primordial germ cells (PGCs) in embryos do not enter meiosis, remain in the proliferative stage, and are referred to as gonocytes, before entering quiescence. Gonocytes develop into SSCs at about 6 days after birth in rodents. Although chromatin structural modification by Polycomb is essential for gene silencing in mammals, and epigenetic changes are critical in spermatogenesis, a comprehensive understanding of transcriptional regulation is lacking. Recently, we evaluated the expression profiles of Yin Yang 1 (YY1) and CP2c in the gonads of E14.5 and 12-week-old mice. YY1 localizes at the nucleus and/or cytoplasm at specific stages of spermatogenesis, possibly by interaction with CP2c and YY1-interacting transcription factor. In the present article, we discuss the possible roles of YY1 and CP2c in spermatogenesis and stemness based on our results and a review of the relevant literature.

12.
J Comput Chem ; 41(1): 6-13, 2020 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-31568571

RESUMO

The elementometalation process is a fundamental chemical step in several catalytic cycles. In this work, density functional theory computations have elucidated the detailed elementometalation mechanism of activated alkyne RCCR(RCO2 Me) by Cp2 TaH3 and rationalized the selectivity in experimental findings. The calculated results show that in the formation process of (E)-olefin monohydride((E)-Pro), the Gibbs free energy barrier is low and the entire reaction is spontaneous and exothermic; thus, (E)-Pro can be formed easily. The formation of (Z)-η2 -olefin monohydride complex ((Z)-Pro) is difficult due to its high Gibbs free energy barrier. The formation process (E)-Pro consists of the following five steps: hydride H1-shift, conformational isomerism 1, hydride H2-shift, conformational isomerism 2, and olefin coordination process. Topological analysis shows that there is a five-membered ring plane structure in the reaction pathway and that the final product (E)-Pro belongs to a typical η2 -olefin monohydride complex. Our calculated results provide an explanation for experimental observations and useful insights for further development of olefin functionalization. © 2019 Wiley Periodicals, Inc.


Assuntos
Teoria da Densidade Funcional , Compostos Organometálicos/química , Termodinâmica , Alcinos/química , Dióxido de Carbono/química , Conformação Molecular , Nióbio/química , Eletricidade Estática , Estereoisomerismo , Tantálio/química
13.
RNA ; 25(7): 757-767, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31010886

RESUMO

Poly(rC)-binding protein 2 (PCBP2, hnRNP E2) is one of the most abundant RNA-binding proteins in mammalian cells. In humans, it exists in seven isoforms, which are assumed to play similar roles in cells. The protein is shown to bind 3'-untranslated regions (3'-UTRs) of many mRNAs and regulate their translation and/or stability, but nothing is known about the functional consequences of PCBP2 binding to 5'-UTRs. Here we show that the PCBP2 isoform f interacts with the 5'-UTRs of mRNAs encoding eIF4G2 (a translation initiation factor with a yet unknown mechanism of action, also known as DAP5) and Cyclin I, and inhibits their translation in vitro and in cultured cells, while the PCBP2 isoform e only affects Cyclin I translation. Furthermore, eIF4G2 participates in a cap-dependent translation of the PCBP2 mRNA. Thus, PCBP2 and eIF4G2 seem to regulate one another's expression via a novel type of feedback loop formed by the translation initiation factor and the RNA-binding protein.


Assuntos
Regiões 5' não Traduzidas/genética , Fator de Iniciação Eucariótico 4G/genética , Biossíntese de Proteínas , RNA Mensageiro/genética , Proteínas de Ligação a RNA/metabolismo , Células Cultivadas , Fator de Iniciação Eucariótico 4G/metabolismo , Humanos , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética
14.
J Mol Model ; 25(5): 115, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30969377

RESUMO

Creating input files to atomistic simulations and quantum chemical calculations in the CP2K software package can be a challenge. Here, we present a new graphical user interface to reduce the complexity of the work needed to run a CP2K calculation as well as the risk for making mistakes. The program is called CP2K Editor, and it provides a user-friendly interface for both new and experienced users. CP2K Editor keeps the construction of the input file simple and manageable. The input files are similarly structured, so they are easy to recognize and adjust if more advanced configurations are needed. Furthermore, we have implemented several methods for analyzing the output data, and a routine to test the best cut-off values. In our group, CP2K Editor has clearly been of great help when creating input files to the CP2K software package.

15.
Oncotarget ; 8(15): 24389-24400, 2017 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-28412749

RESUMO

Recent studies have demonstrated an oncogenic role of the transcription factor (TF) CP2c in hepatocellular carcinoma (HCC) based on a strong correlation between CP2c expression, tumor grade, and aggressiveness. We recently found that CP2c directly interacts with another TF, YY1, which is also overexpressed in multiple cancers, including HCC. To evaluate if these proteins are co-regulated in carcinogenesis, we analyzed the expression of CP2c and YY1 in HCC (n = 136) tissues and examined the correlation between their expression and clinicopathological characteristics of HCC. Receiver operating characteristic analysis exhibited the validity of CP2c and nuclear YY1 expression as a diagnostic factor in HCC tissues. High expression of CP2c was significantly correlated with patient age, and higher histological grade, American Joint Committee on Cancer (AJCC) stage, and small and large vessel invasion in HCC tissues, whereas high expression of nuclear YY1 was significantly associated with higher AJCC stage and small vessel invasion. In univariate and multivariate analyses, high expression of CP2c was significantly correlated with disease free survival (DFS), indicating that CP2c expression is an independent prognostic factor for DFS in HCC patients. Patients with high expression of both CP2c and nuclear YY1 usually had a shorter median survival time and worse DFS prognosis than other patients, suggesting that combined detection of CP2c and nuclear YY1 is a useful prognostic marker in HCC patients.


Assuntos
Carcinoma Hepatocelular/metabolismo , Proteínas de Ligação a DNA/biossíntese , Neoplasias Hepáticas/metabolismo , Fatores de Transcrição/biossíntese , Fator de Transcrição YY1/biossíntese , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proteínas de Ligação a DNA/genética , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Transcrição/genética , Fator de Transcrição YY1/genética
16.
Acta Histochem ; 118(7): 685-692, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27612612

RESUMO

Maintaining stemness and permitting differentiation mediated by combinations of transcription factors (TFs) are key aspects of mammalian spermatogenesis. It has been established that yin yang 1 (YY1), a target factor of mammalian polycomb repressive complex 2 (PRC2) and a regulator of stemness, is involved in the stable maintenance of prophase stage spermatocytes. Recently, we have demonstrated that the TF CP2c partners with YY1 in some cells to antagonistically regulate the other protein's function. To date, the functional roles of YY1 and CP2c in spermatogonial stem cells and their derived germ cells remain unclear. Here, we investigated the expression of YY1 and CP2c in mouse gonocytes and germ cells using tissue immunohistochemical and immunofluorescence analyses. At E14.5, both YY1 and CP2c were stained in gonocytes and Sertoli cells in testicular cords, showing different proportion and density of immunoreactivity. However, in adult testes, YY1 was localized in the nuclei of spermatogonial stem cells and spermatocytes, but not in spermatozoa. It was also detected in spermatogonia and spermatids in a stage-specific manner during spermatogenic cycle. CP2c could be detected mostly in the cytoplasm of spermatocytes but not at all in spermatogonial stem cells, indicating mutually exclusive expression of CP2c and YY1. Interestingly, however, CP2c was stained in the cytoplasm and nucleus of spermatogonia at elongation and release stages, and co-localized with YY1 in the nucleus at grouping, maturation, and releasing stages. Neither YY1 nor CP2c was expressed in spermatozoa. Our data indicate that YY1 strongly localizes in the spermatogonial stem cells and co-localizes heterogeneously with CP2c to permit spermatogenesis, and also suggest that YY1 is essential for stemness of spermatogonial stem cells (SCs) whereas CP2c is critical for the commitment of spermatogonia and during the progression of spermatogonia to spermatids. This evaluation expands our understanding of the molecular mechanism of spermatogonia formation as well as spermatogenesis in general.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Espermatócitos/metabolismo , Espermatogênese/fisiologia , Células-Tronco/citologia , Fatores de Transcrição/metabolismo , Fator de Transcrição YY1/metabolismo , Animais , Diferenciação Celular/fisiologia , Masculino , Camundongos , Espermátides/metabolismo , Espermatogônias/metabolismo , Testículo/metabolismo
17.
Appl Biochem Biotechnol ; 179(4): 650-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26906118

RESUMO

TFCP2L1 is a transcription factor that facilitates establishment and maintenance of pluripotency in embryonic stem cells by forming a complex transcriptional network with other transcription factors (OCT4, SOX2, and NANOG). TFCP2L1 contains two distinct domains, the CP2-like domain at the N-terminus and the SAM-like domain at the C-terminus. In this study, we found that TFCP2L1 is hexamerized in solution via the C-terminal SAM-like domain. We also found that homo-oligomerization of SAM-like domain is dependent on the concentration of the proteins. Finally, we found that TFCP2L1 binds directly to DNA via the N-terminal CP2-like domain.


Assuntos
Diferenciação Celular/genética , Proteínas de Ligação a DNA/química , Células-Tronco Embrionárias/metabolismo , Proteínas Repressoras/química , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Embrionárias/química , Camundongos , Proteína Homeobox Nanog/genética , Proteína Homeobox Nanog/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Fator 3 de Transcrição de Octâmero/metabolismo , Domínios Proteicos/genética , Multimerização Proteica , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo
18.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-853388

RESUMO

Objective: To research the chemical composition from the roots of Lonicera japonica and their anti-inflammatory activities. Methods: The compounds were isolated and purified by chromatography on silica gel column, Sephadex LH-20 column, preparative thin-layer, and semi-preparative HPLC, etc. Their structures were identified on the basis of spectroscopic data, and parts of the isolated compounds were tested for their anti-inflammatory activities against zebrafish. Results: Fourteen compounds were isolated and elucidated as 3,13-dihydroxystemodan-2-one (1), chrysophanol (2), palmarumycin CP2 (3), β-sitosterol (4), stigmasterol (5), stigmast-4,6,8(14), 22-tetraen-3-one (6), erythrinassinate D (7), lanosterin (8), 3-O-acetyloleanolic acid (9), protocatechuin aldehyde (10), daucosterol (11), (E)-3-(3,4-dihydroxybenzylidene)-5-(3,4-dihydroxyphenyl)-2(3H)-furanone (12), lomacarinoside B (13), and (2E,6S)-8-(α-L-arabinopyranosyl-(1″→6')-β-D-glucopyranosyloxy)-2,6-dimethyloct-2-eno-1,2″-lactone (14). Conclusion: Compound 1 is a new compound, and compounds 2, 3, 6, 7-9, and 13 are isolated from L. japonica for the first time. Compounds 9 and 10 show the significant anti-inflammatory activities at 100 μg/mL.

19.
Anal Biochem ; 441(2): 147-51, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23871997

RESUMO

To begin gene transcription, several transcription factors must bind to specific DNA sequences to form a complex via DNA-protein interactions. We established an in vitro method for specific and sensitive analyses of DNA-protein interactions based on a DNA immunoprecipitation (DIP) method. We verified the accuracy and efficiency of the DIP assay in quantitatively measuring DNA-protein binding using transcription factor CP2c as a model. With our DIP assay, we could detect specific interactions within a DNA-CP2c complex, with reproducible and quantitative binding values. In addition, we were able to effectively measure the changes in DNA-CP2c binding by the addition of a small molecule, FQI1 (factor quinolinone inhibitor 1), previously identified as a specific inhibitor of this binding. To identify a new regulator of DNA-CP2c binding, we analyzed several CP2c binding peptides and found that only one class of peptide severely inhibits DNA-CP2c binding. These data show that our DIP assay is very useful in quantitatively detecting the binding dynamics of DNA-protein complex. Because DNA-protein interaction is very dynamic in different cellular environments, our assay can be applied to the detection of active transcription factors, including promoter occupancy in normal and disease conditions. Moreover, it may be used to develop a targeted regulator of specific DNA-protein interaction.


Assuntos
Proteínas de Ligação a DNA/metabolismo , DNA/metabolismo , Imunoprecipitação/métodos , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , DNA/análise , Proteínas de Ligação a DNA/análise , Humanos , Camundongos , Ligação Proteica , Fatores de Transcrição/análise
20.
Korean Journal of Anatomy ; : 343-351, 2006.
Artigo em Coreano | WPRIM (Pacífico Ocidental) | ID: wpr-643849

RESUMO

This experiment was performed to evaluate the morphological responses of the appendicular mucosa of the mouse, inoculated with Ehrlich carcinoma cells in the inguinal area, following administration of BCG or CP-2 (Coptis chinensis-Croton tiglium extracts). Healthy adult ICR mice weighing 25 gm each were divided into normal and experimental groups (experimental control, BCG or CP-2 treated group). Each experimental group mouse was inoculated with 1 x 10(7) Ehrlich carcinoma cells subcutaneously in the inguinal area. From the next day after inoculations, 0.2 mL of saline, BCG (0.5 mL/25 g B.W.: 0.03 x 10(8) ~ 0.32 x 10(8) CFU) or CP-2 (30 mg/kg) were injected subcutaneously to the animals every other day, respectively. The day following the 7 th injection of BCG or CP-2, each mouse was injected with a single dose of 0.7 microCi/gm of methyl-3H-thymidine (25 Ci/mmol, Amersham Lab., England) through tail vein. Seventy minutes after the tritiated thymidine injection, animals were sacrificed. The number of the labeled epithelial cells of the appendicular mucosae were observed and evaluated. On histological studies of the experimental control, BCG or CP-2 treated mice, general morphologies of the appendicular mucosae were similar. On autoradiographic study, number of the labeled cells of normal control, experimental control, BCG treated or CP-2 treated groups were 362.2+/-56.12, 350.7+/-42.65, 265.8+/-27.08 and 241.3+/-53.29, respectively. Above results show that BCG and CP-2 suppress the DNA synthetic activity of the epithelial cells of the appendix, but did not show any remarkable morphological alterations on the mucosae. These results suggest that BCG and CP-2 are ones of effective anticancer drugs for the cytostatic therapy.


Assuntos
Adulto , Animais , Humanos , Camundongos , Apêndice , DNA , Células Epiteliais , Camundongos Endogâmicos ICR , Mucosa , Mycobacterium bovis , Robenidina , Timidina , Veias
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...