scholarly journals Inhibition of Specificity Protein 1 Is Involved in Phloretin-Induced Suppression of Prostate Cancer

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Dan Kang ◽  
Wenren Zuo ◽  
Qingxin Wu ◽  
Qingyi Zhu ◽  
Ping Liu
Keyword(s):  
Prostate Cancer ◽  
Experimental Data ◽  
Cell Growth Inhibition ◽  
Transcription Activity ◽  
Specificity Protein 1 ◽  
Anticancer Mechanism ◽  
Specificity Protein ◽  
Related Proteins

Phloretin is a flavonoid existed in various plants and has been reported to possess anticarcinogenic activity. However, the anticancer mechanism of phloretin in prostate cancer (PCa) remains unclear. Here, our in vitro and in vivo experimental data demonstrate that phloretin inhibits the phosphorylation and the activation of EGFR and then inhibits its downstream PI3K/AKT and MEK/ERK1/2 pathways in PCa cells. Inhibition of these two pathways further decreases expression of Sp1 by inhibiting Sp1 gene transcription, induces degradation of Sp1 protein by inhibiting GSK3β phosphorylation, suppresses nucleolin-enhanced translation of Sp1 mRNA by inhibiting nucleolin phosphorylation, and directly inactivates transcription activity of Sp1. Inhibition of Sp1 subsequently decreases the expression of Sp3/4, VEGF, and Survivin and then upregulates apoptosis-related proteins and downregulates cell cycle-related proteins in PCa cells. Finally, phloretin treatment in PCa cells induces cell growth inhibition and apoptosis, suggesting that phloretin may be an effective therapy compound in the treatment of prostate cancer.

scholarly journals Abnormal nitration and S-sulfhydration of Sp1-CSE-H2S pathway contribute to the progress of hyperhomocysteinemia: a vicious circle

2019 ◽  
Author(s):  
Chenghua Luo ◽  
Dengyu Ji ◽  
Yan Li ◽  
Yan Cao ◽  
Shangyue Zhang ◽  
...  
Keyword(s):  
Therapeutic Strategy ◽  
Vicious Circle ◽  
Post Translational Modification ◽  
Physiological Conditions ◽  
Specificity Protein 1 ◽  
S Deficiency ◽  
Specificity Protein ◽  
Lower Expression

ABSTRACTSp1 (Specificity protein 1)-CSE (cystathionine-γ-lyase)-H2S (hydrogen sulfide) pathway plays an important role in homocysteine-metabolism, whose disorder can result in hyperhomocysteinemia. The deficiency of plasma H2S in patients and animal models with hyperhomocysteinemia has been reported but it is unclear whether this deficiency plays a role in the progress of hyperhomocysteinemia. Furthermore, it remains unknown whether the post-translational modification of Sp1 or CSE mediated by hyperhomocysteinemia itself can in turn affect the development of hyperhomocysteinemia. By both in vivo and in vitro studies, we conducted immunoprecipitation and maleimide assays to detect the post-translational modification of Sp1-CSE-H2S pathway and revealed four major findings: (1) the accumulation of homocysteine augmented the nitration of CSE, thus blunted its bio-activity and caused H2S deficiency. (2) H2S deficiency lowered the S-sulfhydration of Sp1 and inhibited its transcriptional activity, resulted in lower expression of CSE. CSE deficiency decreased the H2S level further, which in turn lowered the S-sulfhydration level of CSE. (3) CSE was S-sulfhydrated at Cys84, Cys109, Cys172, Cys229, Cys252, Cys307 and Cys310 under physiological conditions, mutation of Cys84, Cys109, Cys229, Cys252 and Cys307 decreased its S-sulfhydration level and bio-activity. (4) H2S deficiency could trap hyperhomocysteinemia into a progressive vicious circle and trigger a rapid increase of homocysteine, while blocking nitration or restoring S-sulfhydration could break this circle. In conclusion, this study reveals a novel mechanism involved in the disorder of homocysteine-metabolism, which may provide a candidate therapeutic strategy for hyperhomocysteinemia.

Hsp70 is required for optimal cell proliferation in mouse A6 mesoangioblast stem cells

2009 ◽  
Vol 421 (2) ◽  
pp. 193-200 ◽  
Author(s):  
Giuseppina Turturici ◽  
Fabiana Geraci ◽  
Maria E. Candela ◽  
Giulio Cossu ◽  
Giovanni Giudice ◽  
...  
Keyword(s):  
Stem Cells ◽  
Heat Shock ◽  
Consensus Sequence ◽  
Hsp70 Expression ◽  
Heat Shock Element ◽  
Specificity Protein 1 ◽  
Cell Clones ◽  
Specificity Protein

Mouse Hsp70 (70 kDa heat shock protein) is preferentially induced by heat or stress stimuli. We previously found that Hsp70 is constitutively expressed in A6 mouse mesoangioblast stem cells, but its possible role in these cells and the control of its basal transcription remained unexplored. Here we report that in the absence of stress, Ku factor is able to bind the HSE (heat shock element) consensus sequence in vitro, and in vivo it is bound to the proximal hsp70 promoter. In addition, we show that constitutive hsp70 transcription depends on the co-operative interaction of different factors such as Sp1 (specificity protein 1) and GAGA-binding protein with Ku factor, which binds the HSE consensus sequence. We used mRNA interference assays to select knockdown cell clones. These cells were able to respond to heat stress by producing a large amount of Hsp70, and produced the same amount of Hsp70 as that synthesized by stressed A6 cells. However, severe Hsp70 knockdown cells had a longer duplication time, suggesting that constitutive Hsp70 expression has an effect on the rate of proliferation.

scholarly journals Transcriptional factor specificity protein 1 (SP1) promotes the proliferation of glioma cells by up-regulating midkine (MDK)

2015 ◽  
Vol 26 (3) ◽  
pp. 430-439 ◽  
Author(s):  
Jingyan Luo ◽  
Xiaoxiao Wang ◽  
Zhibo Xia ◽  
Lixuan Yang ◽  
Zhiming Ding ◽  
...  
Keyword(s):  
Chromatin Immunoprecipitation ◽  
Glioma Cells ◽  
Clinical Samples ◽  
Specificity Protein 1 ◽  
Factor Specificity ◽  
Specificity Protein ◽  
Molecular Brain ◽  
Brain Neoplasia

Midkine (MDK) expression is associated with the proliferation of many cancers, including glioma. However, the upstream signaling that leads to MDK accumulation remains elusive. This study investigates the molecular mechanism that induces MDK overexpression in human glioma. The Repository for Molecular Brain Neoplasia Data was analyzed to identify potential MDK regulators. Expression of MDK and specificity protein 1 (SP1) was compared in glioma specimens. Chromatin immunoprecipitation assay was used to confirm the transcriptional regulation. MDK-force–expressed, SP1-silenced glioma cells were used to test rescue effects in vitro and in vivo. MDK and SP1 expression in gliomas was significantly higher than in adjacent tissues and was positively correlated in glioma clinical samples and cell lines. The promoter of the human MDK gene has a putative SP1 binding site. SP1 binds to the promoter of the MDK gene and directly regulates MDK expression. MDK or SP1 gene silencing inhibited the proliferation of glioma cells and reduced the tumor volume in nude mice. Overexpression of MDK in SP1-silenced cells could partially rescue the SP1 inhibition effects in vivo and in vitro. SP1 directly up-regulated the expression of MDK, and the SP1-MDK axis cooperated in glioma tumorigenesis.

794: Valproic Acid Inhibits Prostate Cancer Cell Growth in Vitro and in Vivo

2006 ◽  
Vol 175 (4S) ◽  
pp. 257-257
Author(s):  
Jennifer Sung ◽  
Qinghua Xia ◽  
Wasim Chowdhury ◽  
Shabana Shabbeer ◽  
Michael Carducci ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Valproic Acid ◽  
Cell Growth ◽  
Cancer Cell ◽  
Prostate Cancer Cell ◽  
Cancer Cell Growth

Pleiotropic Effect of Mahanine and Girinimbine Analogs: Anticancer Mechanism and its Therapeutic Versatility

2019 ◽  
Vol 18 (14) ◽  
pp. 1983-1990 ◽  
Author(s):  
V. Lenin Maruthanila ◽  
Ramakrishnan Elancheran ◽  
Ajaikumar B. Kunnumakkar ◽  
Senthamaraikannan Kabilan ◽  
Jibon Kotoky
Keyword(s):  
Biological Effects ◽  
Pleiotropic Effect ◽  
In Vivo Evaluation ◽  
Chemopreventive Agents ◽  
Cycle Arrest ◽  
Wide Range ◽  
Anticancer Mechanism ◽  
Metastasis Development

Emerging evidence present credible support in favour of the potential role of mahanine and girinimbine. Non-toxic herbal carbazole alkaloids occur in the edible part of Murraya koenigii, Micromelum minutum, M. zeylanicum, and M. euchrestiolia. Mahanine and girinimbine are the major potent compounds from these species. In fact, they interfered with tumour expansion and metastasis development through down-regulation of apoptotic and antiapoptotic protein, also involved in the stimulation of cell cycle arrest. Consequently, these compounds were well proven for the in-vitro and in vivo evaluation that could be developed as novel agents either alone or as an adjuvant to conventional therapeutics. Therefore, mahanine and girinimbine analogs have the potential to be the promising chemopreventive agents for the tumour recurrence and the treatment of human malignancies. In this review, an updated wide-range of pleiotropic anticancer and biological effects induction by mahanine and girinimbine against cancer cells were deeply summarized.

scholarly journals Functional Characterization of the mazEF Toxin-Antitoxin System in the Pathogenic Bacterium Agrobacterium tumefaciens

2021 ◽  
Vol 9 (5) ◽  
pp. 1107
Author(s):  
Wonho Choi ◽  
Yoshihiro Yamaguchi ◽  
Ji-Young Park ◽  
Sang-Hyun Park ◽  
Hyeok-Won Lee ◽  
...  
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Physiological Function ◽  
Functional Characterization ◽  
Site Directed Mutagenesis ◽  
In Vitro Assays ◽  
Cell Growth Inhibition ◽  
The Right

Agrobacterium tumefaciens is a pathogen of various plants which transfers its own DNA (T-DNA) to the host plants. It is used for producing genetically modified plants with this ability. To control T-DNA transfer to the right place, toxin-antitoxin (TA) systems of A. tumefaciens were used to control the target site of transfer without any unintentional targeting. Here, we describe a toxin-antitoxin system, Atu0939 (mazE-at) and Atu0940 (mazF-at), in the chromosome of Agrobacterium tumefaciens. The toxin in the TA system has 33.3% identity and 45.5% similarity with MazF in Escherichia coli. The expression of MazF-at caused cell growth inhibition, while cells with MazF-at co-expressed with MazE-at grew normally. In vivo and in vitro assays revealed that MazF-at inhibited protein synthesis by decreasing the cellular mRNA stability. Moreover, the catalytic residue of MazF-at was determined to be the 24th glutamic acid using site-directed mutagenesis. From the results, we concluded that MazF-at is a type II toxin-antitoxin system and a ribosome-independent endoribonuclease. Here, we characterized a TA system in A. tumefaciens whose understanding might help to find its physiological function and to develop further applications.

scholarly journals Conifers Phytochemicals: A Valuable Forest with Therapeutic Potential

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 3005
Author(s):  
Kanchan Bhardwaj ◽  
Ana Sanches Silva ◽  
Maria Atanassova ◽  
Rohit Sharma ◽  
Eugenie Nepovimova ◽  
...  
Keyword(s):  
Experimental Data ◽  
Potential Role ◽  
Therapeutic Potential ◽  
Fungal Infections ◽  
Cell Damage ◽  
Cancer Growth ◽  
Naturally Occurring ◽  
Antioxidant Effects

Conifers have long been recognized for their therapeutic potential in different disorders. Alkaloids, terpenes and polyphenols are the most abundant naturally occurring phytochemicals in these plants. Here, we provide an overview of the phytochemistry and related commercial products obtained from conifers. The pharmacological actions of different phytochemicals present in conifers against bacterial and fungal infections, cancer, diabetes and cardiovascular diseases are also reviewed. Data obtained from experimental and clinical studies performed to date clearly underline that such compounds exert promising antioxidant effects, being able to inhibit cell damage, cancer growth, inflammation and the onset of neurodegenerative diseases. Therefore, an attempt has been made with the intent to highlight the importance of conifer-derived extracts for pharmacological purposes, with the support of relevant in vitro and in vivo experimental data. In short, this review comprehends the information published to date related to conifers’ phytochemicals and illustrates their potential role as drugs.

scholarly journals Dipterocarpus tuberculatus Roxb. Ethanol Extract Has Anti-Inflammatory and Hepatoprotective Effects In Vitro and In Vivo by Targeting the IRAK1/AP-1 Pathway

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2529
Author(s):  
Haeyeop Kim ◽  
Woo Seok Yang ◽  
Khin Myo Htwe ◽  
Mi-Nam Lee ◽  
Young-Dong Kim ◽  
...  
Keyword(s):  
Ethanol Extract ◽  
Serum Levels ◽  
Hepatoprotective Activity ◽  
Tnf Α ◽  
Anti Inflammatory ◽  
Related Proteins ◽  
Pro Inflammatory Cytokines ◽  
Inflammatory Effect

Dipterocarpus tuberculatus Roxb. has been used traditionally as a remedy for many diseases, especially inflammation. Therefore, we analyzed and explored the mechanism of the anti-inflammatory effect of a Dipterocarpus tuberculatus Roxb. ethanol extract (Dt-EE). Dt-EE clearly and dose-dependently inhibited the expression of pro-inflammatory cytokines such as IL-6, TNF-α, and IL-1β in lipopolysaccharide (LPS)-treated RAW264.7 cells. Also, Dt-EE suppressed the activation of the MyD88/TRIF-mediated AP-1 pathway and the AP-1 pathway related proteins JNK2, MKK4/7, and TAK1, which occurred as a result of inhibiting the kinase activity of IRAK1 and IRAK4, the most upstream factors of the AP-1 pathway. Finally, Dt-EE displayed hepatoprotective activity in a mouse model of hepatitis induced with LPS/D-galactosamine (D-GalN) through decreasing the serum levels of alanine aminotransferase and suppressing the activation of JNK and IRAK1. Therefore, our results strongly suggest that Dt-EE could be a candidate anti-inflammatory herbal medicine with IRAK1/AP-1 inhibitory and hepatoprotective properties.

scholarly journals miR-146a-5p Promotes Chondrocyte Apoptosis and Inhibits Autophagy of Osteoarthritis by Targeting NUMB

Cartilage ◽  
2021 ◽  
pp. 194760352110235
Author(s):  
Hongjun Zhang ◽  
Wendi Zheng ◽  
Du Li ◽  
Jia Zheng
Keyword(s):  
Caspase 3 ◽  
Cartilage Tissue ◽  
Luciferase Reporter ◽  
Chondrocyte Apoptosis ◽  
Knee Cartilage ◽  
Before And After ◽  
Related Proteins ◽  
Human And Mouse

Objective miR-146a-5p was found to be significantly upregulated in cartilage tissue of patients with osteoarthritis (OA). NUMB was shown to be involved in the autophagy regulation process of cells. We aimed to learn whether NUMB was involved in the apoptosis or autophagy process of chondrocytes in OA and related with miR-146a-5p. Methods QRT-PCR was used to detect miR-146a-5p level in 22 OA cartilage tissues and 22 controls. The targets of miR-146a-5p were analyzed using software and the luciferase reporter experiment. The apoptosis and autophagy, and related proteins were detected in chondrocytes treated with miR-146a-5p mimic/inhibitor or pcDNA3.1-NUMB/si-NUMB and IL-1β, respectively. In vivo experiment, intra-articular injection of miR-146a-5p antagomir/NC was administered at the knee of OA male mice before and after model construction. Chondrocyte apoptosis and the expression of apoptosis and autophagy-related proteins were also detected. Results miR-146a-5p was highly expressed in knee cartilage tissue of patients with OA, while NUMB was lowly expressed and negatively regulated by miR-146a-5p. Upregulation of miR-146a-5p can promote cell apoptosis and reduce autophagy of human and mouse chondrocytes by modulating the levels of cleaved caspase-3, cleaved PARP, Bax, Beclin 1, ATG5, p62, LC3-I, and LC3-II. Increasing the low level of NUMB reversed the effects of miR-146a-5p on chondrocyte apoptosis and autophagy. Intra-articular injection of miR-146a-5p antagomir can also reverse the effects of miR-146a-5p on the apoptosis and autophagy of knee joint chondrocytes in OA mice. Conclusion Downregulation of miR-146a-5p suppresses the apoptosis and promotes autophagy of chondrocytes by targeting NUMB in vivo and in vitro.

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