scholarly journals Protein kinase D inhibitor CRT0066101 suppresses bladder cancer growth in vitro and xenografts via blockade of the cell cycle at G2/M

2017 ◽  
Vol 75 (5) ◽  
pp. 939-963 ◽  
Author(s):  
Qingdi Quentin Li ◽  
Iawen Hsu ◽  
Thomas Sanford ◽  
Reema Railkar ◽  
Navin Balaji ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Bladder Cancer ◽  
Protein Kinase ◽  
Cancer Growth ◽  
Protein Kinase D

Protein kinase D inhibitor CRT0066101 suppresses bladder cancer growth in vitro and in vivo through induction of cell cycle arrest at the G2-M phase.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e16024-e16024
Author(s):  
Qingdi Quentin Li ◽  
Iawen Hsu ◽  
Thomas Sanford ◽  
Reema S. Railkar ◽  
Piyush K. Agarwal
Keyword(s):  
Cell Cycle ◽  
Flow Cytometry ◽  
Bladder Cancer ◽  
Cyclin B1 ◽  
Cancer Growth ◽  
Protein Kinase D ◽  
Bladder Cancer Cells ◽  
M Phase

e16024 Background: Protein Kinase D (PKD) is implicated in tumor growth, death, invasion, and progression. CRT0066101 is an inhibitor of PKD and has antitumor activity in several types of carcinomas. However, the effect and mechanism of CRT0066101 in bladder cancer remain unknown. Methods: The MTS assay was used to evaluate the ability of CRT0066101 to inhibit cellular proliferation in bladder cancer cells. Cell cycle was analyzed by flow cytometry. Protein expression and phosphorylation were assessed by western blotting. Results: We showed that CRT0066101 suppressed the proliferation and migration of 4 bladder cancer cell lines in vitro. We also demonstrated that CRT0066101 inhibited tumor growth in an in vivo mouse model of bladder cancer. To verify the role of PKD in bladder tumor, we found that PKD2 was highly expressed in 8 bladder cancer lines and that RNA interference-mediated silencing of the PKD2 gene dramatically reduced bladder cancer growth in vitro and in vivo, suggesting that the effect of the compound in bladder cancer is mediated through inhibition of PKD2. This notion was confirmed by demonstrating that the levels of PKD2 and phospho-PKD2 (Ser-876) were markedly decreased in CRT0066101-treated bladder cancer. In addition, our cell cycle analysis by flow cytometry revealed that CRT0066101 arrested bladder cancer cells at the G2-M phase. We further validated these data by immunoblotting showing that treatment of bladder carcinoma cells with CRT0066101 downregulated the expression of cyclin B1, cdc2 and cdc25C, but elevated the levels of p27kip1, gadd45a, chk1/2, and wee1. Finally, CRT0066101 was found to increase the phosphorylation of cdc2 and cdc25C, which lead to reduction in cdc2-cyclin B1 activity. Conclusions: These novel findings suggest that CRT0066101 inhibits bladder cancer growth through modulating the cell cycle G2 checkpoint and inducing cell cycle G2-M arrest, which lead to blockade of cell cycle progression. QQL and IH contributed equally to this work.

scholarly journals A Novel Small-Molecule Inhibitor of Protein Kinase D Blocks Pancreatic Cancer Growth In vitro and In vivo

2010 ◽  
Vol 9 (5) ◽  
pp. 1136-1146 ◽  
Author(s):  
Kuzhuvelil B. Harikumar ◽  
Ajaikumar B. Kunnumakkara ◽  
Nobuo Ochi ◽  
Zhimin Tong ◽  
Amit Deorukhkar ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Protein Kinase ◽  
Small Molecule ◽  
Small Molecule Inhibitor ◽  
Cancer Growth ◽  
Protein Kinase D ◽  
Molecule Inhibitor

414 A Novel Small Molecule Inhibitor of Protein Kinase D Blocks Pancreatic Cancer Growth Both In Vitro and In Vivo

2010 ◽  
Vol 138 (5) ◽  
pp. S-62 ◽  
Author(s):  
Christopher R. Ireson ◽  
Kuzhuvelil B. Harikumar ◽  
Ajaykumar B. Kunnumakkara ◽  
Amit Deorukhkar ◽  
Zhimin Tong ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Protein Kinase ◽  
Small Molecule ◽  
Small Molecule Inhibitor ◽  
Cancer Growth ◽  
Protein Kinase D ◽  
Molecule Inhibitor

scholarly journals Protein kinase D promotes plasticity-induced F-actin stabilization in dendritic spines and regulates memory formation

2015 ◽  
Vol 210 (5) ◽  
pp. 771-783 ◽  
Author(s):  
Norbert Bencsik ◽  
Zsófia Szíber ◽  
Hanna Liliom ◽  
Krisztián Tárnok ◽  
Sándor Borbély ◽  
...  
Keyword(s):  
Synaptic Plasticity ◽  
Protein Kinase ◽  
Dendritic Spines ◽  
Morphological Changes ◽  
Long Term Potentiation ◽  
Memory Formation ◽  
Protein Kinase D

Actin turnover in dendritic spines influences spine development, morphology, and plasticity, with functional consequences on learning and memory formation. In nonneuronal cells, protein kinase D (PKD) has an important role in stabilizing F-actin via multiple molecular pathways. Using in vitro models of neuronal plasticity, such as glycine-induced chemical long-term potentiation (LTP), known to evoke synaptic plasticity, or long-term depolarization block by KCl, leading to homeostatic morphological changes, we show that actin stabilization needed for the enlargement of dendritic spines is dependent on PKD activity. Consequently, impaired PKD functions attenuate activity-dependent changes in hippocampal dendritic spines, including LTP formation, cause morphological alterations in vivo, and have deleterious consequences on spatial memory formation. We thus provide compelling evidence that PKD controls synaptic plasticity and learning by regulating actin stability in dendritic spines.

The Xenopus protein kinase pEg2 associates with the centrosome in a cell cycle-dependent manner, binds to the spindle microtubules and is involved in bipolar mitotic spindle assembly

1998 ◽  
Vol 111 (5) ◽  
pp. 557-572 ◽  
Author(s):  
C. Roghi ◽  
R. Giet ◽  
R. Uzbekov ◽  
N. Morin ◽  
I. Chartrain ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Protein Kinase ◽  
Mitotic Spindle ◽  
Cultured Cells ◽  
Dependent Manner ◽  
Egg Extracts ◽  
Pericentriolar Material ◽  
Spindle Microtubules ◽  
Cycle Dependent

By differential screening of a Xenopus laevis egg cDNA library, we have isolated a 2,111 bp cDNA which corresponds to a maternal mRNA specifically deadenylated after fertilisation. This cDNA, called Eg2, encodes a 407 amino acid protein kinase. The pEg2 sequence shows significant identity with members of a new protein kinase sub-family which includes Aurora from Drosophila and Ipl1 (increase in ploidy-1) from budding yeast, enzymes involved in centrosome migration and chromosome segregation, respectively. A single 46 kDa polypeptide, which corresponds to the deduced molecular mass of pEg2, is immunodetected in Xenopus oocyte and egg extracts, as well as in lysates of Xenopus XL2 cultured cells. In XL2 cells, pEg2 is immunodetected only in S, G2 and M phases of the cell cycle, where it always localises to the centrosomal region of the cell. In addition, pEg2 ‘invades’ the microtubules at the poles of the mitotic spindle in metaphase and anaphase. Immunoelectron microscopy experiments show that pEg2 is located precisely around the pericentriolar material in prophase and on the spindle microtubules in anaphase. We also demonstrate that pEg2 binds directly to taxol stabilised microtubules in vitro. In addition, we show that the presence of microtubules during mitosis is not necessary for an association between pEg2 and the centrosome. Finally we show that a catalytically inactive pEg2 kinase stops the assembly of bipolar mitotic spindles in Xenopus egg extracts.

scholarly journals BK polyomavirus (BKPyV) is a risk factor for bladder cancer through induction of APOBEC3-mediated genomic damage

2021 ◽  
Author(s):  
Simon Charles Baker ◽  
Andrew S Mason ◽  
Raphael G Slip ◽  
Katie T Skinner ◽  
Andrew Macdonald ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Bladder Cancer ◽  
Risk Factor ◽  
The Elderly ◽  
T Antigen ◽  
Transplant Patients ◽  
Adult Kidney ◽  
Bk Polyomavirus ◽  
Vitro Model

Limited understanding of bladder cancer aetiopathology hampers progress in reducing incidence. BK polyomavirus (BKPyV) is a common childhood infection that can be reactivated in the adult kidney leading to viruria. Here we used a mitotically-quiescent, differentiated, normal human urothelial in vitro model to study BKPyV infection. BKPyV infection led to significantly elevated APOBEC3A and APOBEC3B protein, increased deaminase activity and greater numbers of apurinic/apyrimidinic sites in the host urothelial genome. BKPyV Large T antigen (LT-Ag) stimulated re-entry into the cell cycle via inhibition of Retinoblastoma protein and activation of EZH2, E2F1 and FOXM1, which combined to push urothelial cells from G0 into an arrested G2 cell cycle state. The single-stranded DNA displacement loops formed during BKPyV-infection, provide a substrate for APOBEC3 enzymes where they interacted with LT-Ag. These results support reactivated BKPyV infections in adults as a risk factor for bladder cancer in immune-insufficient populations, including transplant patients and the elderly.

scholarly journals Olive Mill Wastewater Inhibits Growth and Proliferation of Cisplatin- and Gemcitabine-Resistant Bladder Cancer Cells In Vitro by Down-Regulating the Akt/mTOR-Signaling Pathway

Nutrients ◽  
2022 ◽  
Vol 14 (2) ◽  
pp. 369
Author(s):  
Jochen Rutz ◽  
Sebastian Maxeiner ◽  
Eva Juengel ◽  
Felix K.-H. Chun ◽  
Igor Tsaur ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Bladder Cancer ◽  
Cancer Cells ◽  
Olive Mill Wastewater ◽  
Mtor Signaling ◽  
Beneficial Effects ◽  
Cycle Arrest ◽  
Bladder Cancer Cells ◽  
Olive Mill

Bladder cancer patients whose tumors develop resistance to cisplatin-based chemotherapy often turn to natural, plant-derived products. Beneficial effects have been particularly ascribed to polyphenols, although their therapeutic relevance when resistance has developed is not clear. The present study evaluated the anti-tumor potential of polyphenol-rich olive mill wastewater (OMWW) on chemo-sensitive and cisplatin- and gemcitabine-resistant T24, RT112, and TCCSUP bladder cancer cells in vitro. The cells were treated with different dilutions of OMWW, and tumor growth and clone formation were evaluated. Possible mechanisms of action were investigated by evaluating cell cycle phases and cell cycle-regulating proteins. OMWW profoundly inhibited the growth and proliferation of chemo-sensitive as well as gemcitabine- and cisplatin-resistant bladder cancer cells. Depending on the cell line and on gemcitabine- or cisplatin-resistance, OMWW induced cell cycle arrest at different phases. These differing phase arrests were accompanied by differing alterations in the CDK-cyclin axis. Considerable suppression of the Akt-mTOR pathway by OMWW was observed in all three cell lines. Since OMWW blocks the cell cycle through the manipulation of the cyclin-CDK axis and the deactivation of Akt-mTOR signaling, OMWW could become relevant in supporting bladder cancer therapy.

scholarly journals Protein Kinase C Signaling Mediates a Program of Cell Cycle Withdrawal in the Intestinal Epithelium

2000 ◽  
Vol 151 (4) ◽  
pp. 763-778 ◽  
Author(s):  
Mark R. Frey ◽  
Jennifer A. Clark ◽  
Olga Leontieva ◽  
Joshua M. Uronis ◽  
Adrian R. Black ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Protein Kinase C ◽  
Protein Kinase ◽  
Intestinal Epithelium ◽  
Molecular Mechanisms ◽  
Model Systems ◽  
Intestinal Epithelial ◽  
Kinase C

Members of the protein kinase C (PKC) family of signal transduction molecules have been widely implicated in regulation of cell growth and differentiation, although the underlying molecular mechanisms involved remain poorly defined. Using combined in vitro and in vivo intestinal epithelial model systems, we demonstrate that PKC signaling can trigger a coordinated program of molecular events leading to cell cycle withdrawal into G0. PKC activation in the IEC-18 intestinal crypt cell line resulted in rapid downregulation of D-type cyclins and differential induction of p21waf1/cip1 and p27kip1, thus targeting all of the major G1/S cyclin-dependent kinase complexes. These events were associated with coordinated alterations in expression and phosphorylation of the pocket proteins p107, pRb, and p130 that drive cells to exit the cell cycle into G0 as indicated by concomitant downregulation of the DNA licensing factor cdc6. Manipulation of PKC isozyme levels in IEC-18 cells demonstrated that PKCα alone can trigger hallmark events of cell cycle withdrawal in intestinal epithelial cells. Notably, analysis of the developmental control of cell cycle regulatory molecules along the crypt–villus axis revealed that PKCα activation is appropriately positioned within intestinal crypts to trigger this program of cell cycle exit–specific events in situ. Together, these data point to PKCα as a key regulator of cell cycle withdrawal in the intestinal epithelium.

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