scholarly journals The Transcriptional Regulation and Ubiquitination Dependent Regulation of Hnrnpk Oncogenic Function in Prostate Tumorigenesis

2021 ◽  
Author(s):  
Huan-Lei Wu ◽  
Sen-Mao Li ◽  
Yao-chen Huang ◽  
Qi-Dong Xia ◽  
Peng Zhou ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Transcriptional Regulation ◽  
Clinical Investigation ◽  
Biological Effects ◽  
Nucleic Acid Binding ◽  
Prostate Tumorigenesis ◽  
Hnrnp K ◽  
Important Player

Abstract Background Heterogeneous nuclear ribonucleoprotein K (hnRNPK) is a nucleic acid-binding protein that regulates diverse biological events. Pathologically, hnRNPK proteins are frequently overexpressed and clinically correlated with poor prognosis to various types of human cancers, therefore pursued as attractive therapeutic targets for selective patients. However, both the transcriptional regulation and degradation of hnRNPK in prostate cancer are remain poorly understood. Methods qRT-PCR was used to detect the expression of hnRNPK and miRNA; Immunoblots and immunohistochemical assays were used to determine the levels of hnRNPK and other proteins. Flow cytometry was used to investigate cell cycle stage. MTS and clonogenic assays were used to investigate cell proliferation. Immunoprecipitation was used to analyze the interaction between SPOP and hnRNPK. A prostate carcinoma xenograft mouse model was used to detect the in vivo effects of hnRNPK and miRNA. Results In the present study, we observed that hnRNPK emerged as an important player in carcinogenesis process of PrCa. miR-206 and miR-613 suppressed hnRNPK expression by targeting the 3’-UTR of hnRNPK in PrCa cell lines, where hnRNP K is overexpressed. In biological effects studies, proliferation and colony formation of PrCa cells in vitro, and tumor growth in vivo, were also dramatically suppressed upon reintroduction of miR-206/ miR-613. We have further provided clear evidence that Cullin 3 SPOP as a novel upstream E3 ubiquitin ligase complex that governs hnRNPK proteins stability and oncogenic functions through promoting the degradation of HnRNP K in a poly-ubiquitinaion dependent proteolysis in the prostate cancer setting. Moreover, prostate cancer-associated SPOP mutants fail to interact with and promote the destruction of hnRNPK proteins. Conclusion Our finding reveal new post-transcriptional and post-translational modifications mechanism of hnRNPK regulation via miR-206/ miR-613 and SPOP, respectively. More important, given the critical oncogenic role of hnRNPK and high frequency of SPOP mutation in prostate cancer, our results provide a molecular rationale for the clinical investigation of novel strategies to combat prostate cancer based on SPOP genetic status.

scholarly journals Transcriptional regulation and ubiquitination-dependent regulation of HnRNPK oncogenic function in prostate tumorigenesis

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Huan-Lei Wu ◽  
Sen-Mao Li ◽  
Yao-chen Huang ◽  
Qi-Dong Xia ◽  
Peng Zhou ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Transcriptional Regulation ◽  
Clinical Investigation ◽  
Nucleic Acid Binding ◽  
Prostate Tumorigenesis ◽  
Ubiquitin Ligase Complex ◽  
Important Player ◽  
Cullin 3

Abstract Background Heterogeneous nuclear ribonucleoprotein K (HnRNPK) is a nucleic acid-binding protein that regulates diverse biological events. Pathologically, HnRNPK proteins are frequently overexpressed and clinically correlated with poor prognosis in various types of human cancers and are therefore pursued as attractive therapeutic targets for select patients. However, both the transcriptional regulation and degradation of HnRNPK in prostate cancer remain poorly understood. Methods qRT-PCR was used to detect the expression of HnRNPK mRNA and miRNA; Immunoblots and immunohistochemical assays were used to determine the levels of HnRNPK and other proteins. Flow cytometry was used to investigate cell cycle stage. MTS and clonogenic assays were used to investigate cell proliferation. Immunoprecipitation was used to analyse the interaction between SPOP and HnRNPK. A prostate carcinoma xenograft mouse model was used to detect the in vivo effects of HnRNPK and miRNA. Results In the present study, we noted that HnRNPK emerged as an important player in the carcinogenesis process of prostate cancer. miR-206 and miR-613 suppressed HnRNPK expression by targeting its 3’-UTR in PrCa cell lines in which HnRNPK is overexpressed. To explore the potential biological function, proliferation and colony formation of PrCa cells in vitro and tumor growth in vivo were also dramatically suppressed upon reintroduction of miR-206/miR-613. We have further provided evidence that Cullin 3 SPOP is a novel upstream E3 ubiquitin ligase complex that governs HnRNPK protein stability and oncogenic functions by promoting the degradation of HnRNPK in polyubiquitination-dependent proteolysis in the prostate cancer setting. Moreover, prostate cancer-associated SPOP mutants fail to interact with and promote the destruction of HnRNPK proteins. Conclusion Our findings reveal new posttranscriptional and posttranslational modification mechanisms of HnRNPK regulation via miR-206/miR-613 and SPOP, respectively. More importantly, given the critical oncogenic role of HnRNPK and the high frequency of SPOP mutations in prostate cancer, our results provide a molecular rationale for the clinical investigation of novel strategies to combat prostate cancer based on SPOP genetic status.

In Vitro Testing of Cyto- and Genotoxicity of New Porphyrin Water-Soluble Metal Derivatives

2007 ◽  
Vol 26 (6) ◽  
pp. 497-502 ◽  
Author(s):  
Gennadi Gasparyan ◽  
Galina Hovhannisyan ◽  
Robert Ghazaryan ◽  
Lida Sahakyan ◽  
Artak Tovmasyan ◽  
...  
Keyword(s):  
Clinical Investigation ◽  
Biological Effects ◽  
Simian Virus 40 ◽  
Simian Virus ◽  
Water Soluble ◽  
Trypan Blue Exclusion ◽  
African Green Monkey Kidney ◽  
Metal Derivatives

Porphyrins and porphyrin derivatives have an outstanding potential for discovery of novel pharmacological agents due to their ability for numerous chemical modifications and a variety of mechanisms of biological effects. New water-soluble Ag and Zn derivatives of tetrachloride meso-tetra (4- N-oxiethylpyridyl) porphyne were synthesized. Cyto- and genotoxicity of these substances were tested in vitro by the vital dye (trypan blue) exclusion and the micronucleus tests, respectively. Both metalloporphyrins were shown to be cytotoxic for Cos-7 (fibroblast-like African green monkey kidney cells transformed by simian virus 40 [SV40]), DU 145 (epithelial-like cells of human prostate carcinoma), and K-562 (human chronic myeloid leukemia cells) cell lines. At the same time they did not cause chromosome fragmentation in K-562 cell line at as high concentrations as IC50 (20 μmol/L for Ag and 70 μmol/L for Zn derivative). Thus, the metalloporphyrins tested meet at least two important demands to potential anticancer drugs as they combine the cytotoxicity with low genotoxicity. The three in vitro tumor models used are relevant to further in vitro and in vivo pre-clinical investigation of the studied metalloporphyrins as potential chemotherapeutics.

scholarly journals SPOP-mediated ubiquitination and degradation of PDK1 suppresses AKT kinase activity and oncogenic functions

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Qiwei Jiang ◽  
Nana Zheng ◽  
Lang Bu ◽  
Xiaomei Zhang ◽  
Xiaoling Zhang ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Protein Kinase ◽  
Glycogen Synthase ◽  
Biological Effects ◽  
E3 Ligase ◽  
Dependent Manner ◽  
Akt Kinase ◽  
Casein Kinase 1

Abstract Background 3-phosphoinositide-dependent protein kinase-1 (PDK1) acts as a master kinase of protein kinase A, G, and C family (AGC) kinase to predominantly govern cell survival, proliferation, and metabolic homeostasis. Although the regulations to PDK1 downstream substrates such as protein kinase B (AKT) and ribosomal protein S6 kinase beta (S6K) have been well established, the upstream regulators of PDK1, especially its degrader, has not been defined yet. Method A clustered regularly interspaced short palindromic repeats (CRISPR)-based E3 ligase screening approach was employed to identify the E3 ubiquitin ligase for degrading PDK1. Western blotting, immunoprecipitation assays and immunofluorescence (IF) staining were performed to detect the interaction or location of PDK1 with speckle-type POZ protein (SPOP). Immunohistochemistry (IHC) staining was used to study the expression of PDK1 and SPOP in prostate cancer tissues. In vivo and in vitro ubiquitination assays were performed to measure the ubiquitination conjugation of PDK1 by SPOP. In vitro kinase assays and mass spectrometry approach were carried out to identify casein kinase 1 (CK1) and glycogen synthase kinase 3 (GSK3)-mediated PDK1 phosphorylation. The biological effects of PDK1 mutations and correlation with SPOP mutations were performed with colony formation, soft agar assays and in vivo xenograft mouse models. Results We identified that PDK1 underwent SPOP-mediated ubiquitination and subsequent proteasome-dependent degradation. Specifically, SPOP directly bound PDK1 by the consensus degron in a CK1/GSK3β-mediated phosphorylation dependent manner. Pathologically, prostate cancer patients associated mutations of SPOP impaired PDK1 degradation and thus activated the AKT kinase, resulting in tumor malignancies. Meanwhile, mutations that occurred around or within the PDK1 degron, by either blocking SPOP to bind the degron or inhibiting CK1 or GSK3β-mediated PDK1 phosphorylation, could markedly evade SPOP-mediated PDK1 degradation, and played potently oncogenic roles via activating the AKT kinase. Conclusions Our results not only reveal a physiological regulation of PDK1 by E3 ligase SPOP, but also highlight the oncogenic roles of loss-of-function mutations of SPOP or gain-of-function mutations of PDK1 in tumorigenesis through activating the AKT kinase.

scholarly journals Cyclocreatine suppresses prostate tumorigenesis through dual effects on SAM and creatine metabolism

2021 ◽  
Author(s):  
Rachana Patel ◽  
Lisa Rodgers ◽  
Catriona A. Ford ◽  
Linda K Rushworth ◽  
Janis Fleming ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Cancer Progression ◽  
De Novo ◽  
Basal Respiration ◽  
Genetically Engineered ◽  
Prostate Tumorigenesis ◽  
Genetically Engineered Mouse Model ◽  
Creatine Metabolism

ABSTRACTProstate cancer is highly prevalent, being the second most common cause of cancer mortality in men worldwide. Applying a novel genetically engineered mouse model (GEMM) of aggressive prostate cancer driven by deficiency of PTEN and SPRY2 (Sprouty 2) tumour suppressors, we identified enhanced creatine metabolism within the phosphagen system in progressive disease. Altered creatine metabolism was validated in in vitro and in vivo prostate cancer models and in clinical cases. Upregulated creatine levels were due to increased uptake through the SLC6A8 creatine transporter and de novo synthesis, resulting in enhanced cellular basal respiration. Treatment with cyclocreatine (a creatine analogue that potently and specifically blocks the phosphagen system) dramatically reduces creatine and phosphocreatine levels. Blockade of creatine biosynthesis by cyclocreatine leads to cellular accumulation of S-adenosyl methionine (SAM), an intermediary of creatine biosynthesis, and suppresses prostate cancer growth in vitro. Furthermore, cyclocreatine treatment impairs cancer progression in our GEMM and in a xenograft liver metastasis model. Hence, by targeting the phosphagen system, cyclocreatine results in anti-tumourigenic effects from both SAM accumulation and suppressed phosphagen system.

scholarly journals Identification and Characterization of Antimicrobial Peptides From Butterflies: An Integrated Bioinformatics and Experimental Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Min Wang ◽  
Ziyue Zhou ◽  
Simin Li ◽  
Wei Zhu ◽  
Xianda Hu
Keyword(s):  
Antimicrobial Peptides ◽  
Therapeutic Potential ◽  
Biological Effects ◽  
Future Research ◽  
Nucleic Acid Binding ◽  
Antibacterial And Antifungal Activities ◽  
Antibacterial And Antifungal ◽  
Biophysical Changes

Butterflies represent one of the largest animal groups on Earth, yet antimicrobial peptides (AMPs) of this group are less studied in comparison with their moth counterparts. This study employed an integrated bioinformatics approach to survey natural AMPs from publicly available genomic datasets. Numerous AMPs, including cecropins, defensins, and moricins, were identified and subsequently used as templates for the design of a series of synthetic AMPs that mimicked the naturally occurring sequences. Despite differing biological effects among the various sequences, the synthetic AMPs exhibited potent antibacterial and antifungal activities in vitro and in vivo, without inducing hemolysis, which implied their therapeutic potential in infectious diseases. Electron and confocal fluorescence microscopies revealed that the AMPs induced distinct morphological and biophysical changes on microbial cell membranes and nuclei, suggesting that the antimicrobial effects were related to a mechanism of membrane penetration and nucleic acid binding by the peptides. In conclusion, this study not only offers insights into butterfly AMPs but also provides a practical strategy for high-throughput natural AMP discoveries that will have implications for future research in this area.

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

The role of aromatic microbial metabolites

2018 ◽  
pp. 97-108
Author(s):  
Н.В. Белобородова ◽  
В.В. Мороз ◽  
А.Ю. Бедова
Keyword(s):  
Process Integration ◽  
Biological Effects ◽  
Clinical Findings ◽  
Multiple Organ ◽  
Critical Conditions ◽  
Clear Understanding ◽  
Microbial Metabolites ◽  
Blood Concentrations

Интеграция метаболизма макроорганизма и его микробиоты, обеспечивающая в норме симбиоз и саногенез, нарушается при заболеваниях, травме, критическом состоянии, и вектор взаимодействия может изменяться в пользу прокариотов по принципу «метаболиты бактерий - против хозяина». Анализ литературы показал, что, с одной стороны, имеется живой интерес к ароматическим микробным метаболитам, с другой - отсутствует четкое представление об их роли в организме человека. Публикации, касающиеся ряда ароматических микробных метаболитов (фенилкарбоновых кислот, ФКК), как правило, не связаны между собой по тематике и направлены на решение тех или иных прикладных задач в разных областях биологии и медицины. Цель обзора - анализ информации о происхождении, биологических эффектах ФКК в экспериментах in vitro и in vivo , и клинических наблюдениях. Обобщая результаты приведенных в обзоре исследований на клеточном, субклеточном и молекулярном уровнях, логично предположить участие ароматических микробных метаболитов в патогенезе полиорганной недостаточности при сепсисе. Наиболее перспективным для раскрытия роли ароматических микробных метаболитов представляется изучение механизмов вторичной почечной недостаточности и септической энцефалопатии. Важным направлением для будущих исследований является изучение влияния продуктов микробной биодеградации ароматических соединений на развитие диссеминированного внутрисосудистого свертывания крови, артериальной гипотензии и септического шока. Результаты дальнейших исследований будут иметь не только фундаментальное значение, но и обогатят практическую медицину новыми диагностическими и лечебными технологиями. Significant increases in blood concentrations of some aromatic metabolites (phenylcarboxylic acids, PhCAs) in patients with sepsis have been previously shown. Enhanced bacterial biodegradation of aromatic compounds has been demonstrated to considerably contribute to this process. Integration of macroorganism metabolism and its microbiota, which provides normal symbiosis and sanogenesis, is disturbed in diseases, trauma, and critical conditions. Direction of this interaction may change in favor of prokaryotes according to the principle, “bacterial metabolites are against the host”. Analysis of literature showed a particular interest of many investigators to aromatic microbial metabolites. However, there is no clear understanding of their role in the human body. Publications on PhCAs are generally not thematically interrelated and usually focus on solving applied tasks in different fields of biology and medicine. The aim of this work was to consolidate existing information about origin and biological effects of PhCAs in in vitro / in vivo experiments and some clinical findings. The presented summary of reported data from studies performed at cellular, sub-cellular, and molecular levels suggests participation of aromatic microbial metabolites in the pathogenesis of multiple organ failure in sepsis. Studying mechanisms of secondary renal failure and septic encephalopathy is most promising for discovering the function of aromatic microbial metabolites. Effects of microbial biodegradation products of aromatic substances on development of disseminated intravascular coagulation, hypotension, and septic shock are an important challenge for future studies. Results of further investigations will be not only fundamental, but will also enrich medical practice with new diagnostic and therapeutic technologies.

Antioxidant Activity, Phenolic Content and Hematoprotective Effects of Cleome arabica Polyphenolic Leaf Extract

2019 ◽  
Author(s):  
C. Tigrine ◽  
A. Kameli
Keyword(s):  
Antioxidant Activity ◽  
Biological Effects ◽  
Reducing Power ◽  
Hematological Toxicity ◽  
Protective Effects ◽  
Ferrous Ions ◽  
Polyphenolic Extract ◽  
Cleome Arabica

In this study a polyphenolic extract from Cleome arabica leaves (CALE) was investigated for its antioxidant activity in vitro using DPPH•, metal chelating and reducing power methods and for its protective effects against AraC-induced hematological toxicity in vivo using Balb C mice. Results indicated that CALE exhibited a strong and dose-dependent scavenging activity against the DPPH• free radical (IC50 = 4.88 μg/ml) and a high reducing power activity (EC50 = 4.85 μg/ml). Furthermore, it showed a good chelating effects against ferrous ions (IC50 = 377.75 μg/ml). The analysis of blood showed that subcutaneous injection of AraC (50 mg/kg) to mice during three consecutive days caused a significant myelosupression (P < 0.05). The combination of CALE and AraC protected blood cells from a veritable toxicity. Where, the number of the red cells, the amount of hemoglobin and the percentage of the hematocrite were significantly high. On the other hand, AraC cause an elevation of body temperature (39 °C) in mice. However, the temperature of the group treated with CALE and AraC remained normal and did not exceed 37.5 °C. The observed biological effects of CALE, in vitro as well as in vivo, could be due to the high polyphenol and flavonoid contents. In addition, the antioxidant activity of CALE suggested to be responsible for its hematoprotective effect.

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