In vivo inhibition of cyclin B degradation and induction of cell-cycle arrest in mammalian cells by the neutral cysteine protease inhibitor N-acetylleucylleucylnorleucinal.

ABSTRACT Experiments from several different organisms have demonstrated that polo-like kinases are involved in many aspects of mitosis and cytokinesis. Here, we provide evidence to show that Plk1 associates with chaperonin-containing TCP1 complex (CCT) both in vitro and in vivo. Silencing of CCT by use of RNA interference (RNAi) in mammalian cells inhibits cell proliferation, decreases cell viability, causes cell cycle arrest with 4N DNA content, and leads to apoptosis. Depletion of CCT in well-synchronized HeLa cells causes cell cycle arrest at G2, as demonstrated by a low mitotic index and Cdc2 activity. Complete depletion of Plk1 in well-synchronized cells also leads to G2 block, suggesting that misfolded Plk1 might be responsible for the failure of CCT-depleted cells to enter mitosis. Moreover, partial depletion of CCT or Plk1 leads to mitotic arrest. Finally, the CCT-depleted cells reenter the cell cycle upon reintroduction of the purified constitutively active form of Plk1, indicating that Plk1 might be a CCT substrate.

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Trichosanthes dioica seed lectin inhibits Ehrlich ascites carcinoma cells growth in vivo in mice by inducing G 0 /G 1 cell cycle arrest

Journal of Food Biochemistry ◽

10.1111/jfbc.13714 ◽

2021 ◽

Author(s):

Shaikh Shohidul Islam ◽

Md. Rezaul Karim ◽

A. K. M. Asaduzzaman ◽

A. H. M. Khurshid Alam ◽

Zahid Hayat Mahmud ◽

...

Keyword(s):

Cell Cycle ◽

Cell Cycle Arrest ◽

Ehrlich Ascites Carcinoma ◽

Carcinoma Cells ◽

Cycle Arrest ◽

Ehrlich Ascites ◽

Trichosanthes Dioica

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Selective Inhibition of Aurora Kinase A by AK-01/LY3295668 Attenuates MCC Tumor Growth by Inducing MCC Cell Cycle Arrest and Apoptosis

Cancers ◽

10.3390/cancers13153708 ◽

2021 ◽

Vol 13 (15) ◽

pp. 3708

Author(s):

Bhaba K. Das ◽

Aarthi Kannan ◽

Quy Nguyen ◽

Jyoti Gogoi ◽

Haibo Zhao ◽

...

Keyword(s):

Cell Cycle ◽

Cell Cycle Arrest ◽

Checkpoint Inhibitors ◽

Treatment Options ◽

Standard Of Care ◽

Aurora Kinase ◽

Selective Inhibition ◽

Potential Candidate ◽

Cycle Arrest

Merkel cell carcinoma (MCC) is an often-lethal skin cancer with increasing incidence and limited treatment options. Although immune checkpoint inhibitors (ICI) have become the standard of care in advanced MCC, 50% of all MCC patients are ineligible for ICIs, and amongst those treated, many patients develop resistance. There is no therapeutic alternative for these patients, highlighting the urgent clinical need for alternative therapeutic strategies. Using patient-derived genetic insights and data generated in our lab, we identified aurora kinase as a promising therapeutic target for MCC. In this study, we examined the efficacy of the recently developed and highly selective AURKA inhibitor, AK-01 (LY3295668), in six patient-derived MCC cell lines and two MCC cell-line-derived xenograft mouse models. We found that AK-01 potently suppresses MCC survival through apoptosis and cell cycle arrest, particularly in MCPyV-negative MCC cells without RB expression. Despite the challenge posed by its short in vivo durability upon discontinuation, the swift and substantial tumor suppression with low toxicity makes AK-01 a strong potential candidate for MCC management, particularly in combination with existing regimens.

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W436, a novel SMART derivative, exhibits anti‐hepatocarcinoma activity by inducing apoptosis and G2/M cell cycle arrest in vitro and in vivo and induces protective autophagy

Journal of Biochemical and Molecular Toxicology ◽

10.1002/jbt.22831 ◽

2021 ◽

Author(s):

Shuai Man ◽

Zhuzhu Wu ◽

Rui Sun ◽

Qi Guan ◽

Zengqiang Li ◽

...

Keyword(s):

Cell Cycle ◽

Cell Cycle Arrest ◽

M Cell ◽

Cycle Arrest

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Roquin1 Suppresses Breast Cancer Growth by Inducing Cell Cycle Arrest via Selectively Destabilizing Cell Cycle–Promoting Gene mRNAs

10.21203/rs.3.rs-53499/v1 ◽

2020 ◽

Author(s):

Wenbao Lu ◽

Meicen Zhou ◽

Bing Wang ◽

Xueting Liu ◽

Bingwei Li

Keyword(s):

Breast Cancer ◽

Cell Cycle ◽

Cell Proliferation ◽

Cell Cycle Arrest ◽

Breast Cancer Cell ◽

Breast Tumor ◽

Cell Cycle Progression ◽

Cycle Progression ◽

Cycle Arrest

Abstract Background: Dysregulation of cell cycle progression is one of the common features of human cancer cells, however, its mechanism remains unclear. This study aims to clarify the role and the underlying mechanisms of Roquin1 in cell cycle arrest induction in breast cancer.Methods: Public cancer databases were analyzed to identify the expression pattern of Roquin1 in human breast cancers and the significant association with patient survival. Quantitative real-time PCR and western blots were performed to detect the expression of Roquin1 in breast cancer samples and cell lines. Cell counting, MTT assay, flow cytometry, and in vivo study were conducted to investigate the effects of Roquin1 on cell proliferation, cell cycle progression and tumor progression. RNA-sequencing was applied to identify the differential genes and pathways regulated by Roquin1. RNA immunoprecipitation assay, luciferase reporter assay, mRNA half-life detection, RNA affinity binding assay, and RIP-ChIP were used to explore the molecular mechanisms of Roquin1.Results: We showed that Roquin1 expression in breast cancer tissues and cell lines was inhibited, and the reduction in Roquin1 expression was associated with poor overall survival and relapse free survival of patients with breast cancer. Roquin1 overexpression inhibited breast cancer cell proliferation and induced G1/S cell cycle arrest without causing significant apoptosis. In contrast, knockdown of Roquin1 promoted breast cancer cell growth and cycle progression. Moreover, in vivo induction of Roquin1 by adenovirus significantly suppressed breast tumor growth and metastasis. Mechanistically, Roquin1 selectively destabilizing cell cycle–promoting genes, including Cyclin D1, Cyclin E1, cyclin dependent kinase 6 (CDK6) and minichromosome maintenance 2 (MCM2) through targeting the stem–loop structure in the 3’untranslated region (3’UTR) of mRNAs via its ROQ domain, leading to the downregulation of cell cycle–promoting mRNAs.Conclusions: Our findings demonstrated that Roquin1 was a novel breast tumor suppressor and could induce G1/S cell cycle arrest by selectively downregulating the expression of cell cycle–promoting genes, which might as a potential molecular target for breast cancer treatment.

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Dual effect of 2-methoxyestradiol on cell cycle events in human osteosarcoma 143B cells.

Acta Biochimica Polonica ◽

10.18388/abp.2002_3821 ◽

2002 ◽

Vol 49 (1) ◽

pp. 59-65 ◽

Cited By ~ 16

Author(s):

Justyna Gołebiewska ◽

Piotr Rozwadowski ◽

Jan Henryk Spodnik ◽

Narcyz Knap ◽

Takashi Wakabayashi ◽

...

Keyword(s):

Cell Cycle ◽

Cell Cycle Arrest ◽

Growth Inhibitor ◽

Cytotoxic Action ◽

M Cell ◽

Human Osteosarcoma ◽

Cycle Arrest ◽

M Phase ◽

The Stability

We have demonstrated for the first time that the steroid metabolite, 2-methoxyestradiol (2-ME) is a powerful growth inhibitor of human osteosarcoma 143 B cell line by pleiotropic mechanisms involving cell cycle arrest at two different points and apoptosis. The ability of 2-ME to inhibit cell cycle at the respective points has been found concentration dependent. 1 microM 2-ME inhibited cell cycle at G1 phase while 10 microM 2-ME caused G2/M cell cycle arrest. As a natural estrogen metabolite 2-ME is expected to perturb the stability of microtubules (MT) in vivo analogously to Taxol--the MT binding anticancer agent. Contrary to 2-ME, Taxol induced accumulation of osteosarcoma cells in G2/M phase of cell cycle only. The presented data strongly suggest two different mechanisms of cytotoxic action of 2-ME at the level of a single cell.

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Effect of phenyl vinyl sulphone cysteine protease inhibitor on Schistosoma mansoni: in vitro and in vivo experimental studies

Journal of Parasitic Diseases ◽

10.1007/s12639-017-0933-3 ◽

2017 ◽

Vol 41 (4) ◽

pp. 1049-1058

Author(s):

Manal Salah El-Din Mahmoud ◽

Ayman Nabil Ibrahim ◽

Abeer Fathy Badawy ◽

Nourhan Mohamed Abdelmoniem

Keyword(s):

Protease Inhibitor ◽

Schistosoma Mansoni ◽

Cysteine Protease ◽

Experimental Studies ◽

Cysteine Protease Inhibitor ◽

Phenyl Vinyl

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Identification, characterization and localization of chagasin, a tight-binding cysteine protease inhibitor inTrypanosoma cruzi

Journal of Cell Science ◽

10.1242/jcs.114.21.3933 ◽

2001 ◽

Vol 114 (21) ◽

pp. 3933-3942 ◽

Cited By ~ 4

Author(s):

Ana C. S. Monteiro ◽

Magnus Abrahamson ◽

Ana P. C. A. Lima ◽

Marcos A. Vannier-Santos ◽

Julio Scharfstein

Keyword(s):

Cell Surface ◽

Protease Inhibitor ◽

Cysteine Protease ◽

Mammalian Cells ◽

Tight Binding ◽

Cysteine Proteases ◽

Host Cells ◽

Cysteine Protease Inhibitor ◽

Reversible Inhibitor ◽

Mammalian Host

Lysosomal cysteine proteases from mammalian cells and plants are regulated by endogenous tight-binding inhibitors from the cystatin superfamily. The presence of cystatin-like inhibitors in lower eukaryotes such as protozoan parasites has not yet been demonstrated, although these cells express large quantities of cysteine proteases and may also count on endogenous inhibitors to regulate cellular proteolysis. Trypanosoma cruzi, the causative agent of Chagas’ heart disease, is a relevant model to explore this possibility because these intracellular parasites rely on their major lysosomal cysteine protease (cruzipain) to invade and multiply in mammalian host cells. Here we report the isolation, biochemical characterization, developmental stage distribution and subcellular localization of chagasin, an endogenous cysteine protease inhibitor in T. cruzi. We used high temperature induced denaturation to isolate a heat-stable cruzipain-binding protein (apparent molecular mass, 12 kDa) from epimastigote lysates. This protein was subsequently characterized as a tight-binding and reversible inhibitor of papain-like cysteine proteases. Immunoblotting indicated that the expression of chagasin is developmentally regulated and inversely correlated with that of cruzipain. Gold-labeled antibodies localized chagasin to the flagellar pocket and cytoplasmic vesicles of trypomastigotes and to the cell surface of amastigotes. Binding assays performed by probing living parasites with fluorescein (FITC)-cruzipain or FITC-chagasin revealed the presence of both inhibitor and protease at the cell surface of amastigotes. The intersection of chagasin and cruzipain trafficking pathways may represent a checkpoint for downstream regulation of proteolysis in trypanosomatid protozoa.

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Menadione reduces CDC25B expression and promotes tumor shrinkage in gastric cancer

Therapeutic Advances in Gastroenterology ◽

10.1177/1756284819895435 ◽

2020 ◽

Vol 13 ◽

pp. 175628481989543

Author(s):

Amanda Braga Bona ◽

Danielle Queiroz Calcagno ◽

Helem Ferreira Ribeiro ◽

José Augusto Pereira Carneiro Muniz ◽

Giovanny Rebouças Pinto ◽

...

Keyword(s):

Gastric Cancer ◽

Cell Cycle ◽

Cell Cycle Arrest ◽

Cell Lines ◽

Specific Inhibitor ◽

Gastric Carcinogenesis ◽

In Vivo Experiments ◽

Cycle Arrest

Background: Gastric cancer is one of the most incident types of cancer worldwide and presents high mortality rates and poor prognosis. MYC oncogene overexpression is a key event in gastric carcinogenesis and it is known that its protein positively regulates CDC25B expression which, in turn, plays an essential role in the cell division cycle progression. Menadione is a synthetic form of vitamin K that acts as a specific inhibitor of the CDC25 family of phosphatases. Methods: To better understand the menadione mechanism of action in gastric cancer, we evaluated its molecular and cellular effects in cell lines and in Sapajus apella, nonhuman primates from the new world which had gastric carcinogenesis induced by N-Methyl-N-nitrosourea. We tested CDC25B expression by western blot and RT-qPCR. In-vitro assays include proliferation, migration, invasion and flow cytometry to analyze cell cycle arrest. In in-vivo experiments, in addition to the expression analyses, we followed the preneoplastic lesions and the tumor progression by ultrasonography, endoscopy, biopsies, histopathology and immunohistochemistry. Results: Our tests demonstrated menadione reducing CDC25B expression in vivo and in vitro. It was able to reduce migration, invasion and proliferation rates, and induce cell cycle arrest in gastric cancer cell lines. Moreover, our in-vivo experiments demonstrated menadione inhibiting tumor development and progression. Conclusions: We suggest this compound may be an important ally of chemotherapeutics in the treatment of gastric cancer. In addition, CDC25B has proven to be an effective target for investigation and development of new therapeutic strategies for this malignancy.

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