Nucleic Acid-Driven Aggregation-Induced Emission of Au Nanoclusters for Visualizing Telomerase Activity in Living Cells and In Vivo

2021 ◽  
Author(s):  
Xiang Ran ◽  
Zhenzhen Wang ◽  
Fang Pu ◽  
Enguo Ju ◽  
Jinsong Ren ◽  
...  
Keyword(s):  
Nucleic Acid ◽  
Cancer Cells ◽  
Clinical Diagnosis ◽  
Telomerase Activity ◽  
Living Cells ◽  
Detection Methods ◽  
Au Nanoclusters ◽  
Visual Monitoring

Visual monitoring of telomerase activity in living cancer cells and in vivo is essential for clinical diagnosis and treatment. However, most detection methods were performed in vitro due to the...

Mouse prostate tumor inhibition via disruption of murine telomerase: In vivo and in vitro data for a new preclinical cancer model

2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e14631-e14631
Author(s):  
T. Xu ◽  
Y. Xu ◽  
R. Lao ◽  
K. He ◽  
L. Xue ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Dna Damage ◽  
Cancer Cells ◽  
Cancer Cell Line ◽  
Telomerase Activity ◽  
Telomerase Rna ◽  
Prostate Cancer Cells ◽  
Mouse Prostate

e14631 Background: Telomerase-interference (TI), a novel therapeutic strategy, exploits the high telomerase activity in prostate cancer by introducing a mutated telomerase RNA (MT-Ter) that encodes toxic telomeres. Until now, TI has been tested by targeting human telomerase in tumor cells xenografted into immuno-deficient mice, an inadequate model for predicting efficacy and toxicity. We designed and validated 2 new TI gene constructs that specifically target murine telomerase RNA (mTER), enabling the study of TI in preclinical mouse models that are immuno-competent and that develop endogenous prostate tumors. Methods: We designed 2 constructs and cloned them into a lentiviral delivery system: MT-mTER and siRNA against wild type mTer (α-mTer-siRNA). Using a mouse prostate cancer cell line, E4, we tested the 2 constructs for expression (RT-PCR), telomerase activity (TRAP), and biologic activity (53bp1 DNA damage staining, MTS growth assay, TUNEL and caspase apoptosis assays), as well as in vivo efficacy (NOD-SCID allografts). Results: We confirmed MT-mTER expression (∼50-fold) and showed that α-mTer-siRNA specifically depleted WT-mTER (80% reduction) but not MT-mTER when the 2 constructs are co-expressed; thus, the 2 constructs in combination effectively substituted MT-mTer for WT-mTer in the mouse prostate cancer cells. MT-mTER caused mutant telomeric repeats (TTTGGG instead of TTAGGG) to be added to the ends of telomeres, resulting in rapid telomeric uncapping marked by 53bp1 DNA damage foci (an average 7.5 foci/cell vs. 1.4 foci/cell in vector control). This, in turn, led to rapid and significant apoptosis (>90% TUNEL and caspase +) and growth inhibition in vitro (90% reduction by MTS) and in vivo (75% reduction in tumor allograft size). Conclusions: We successfully designed and validated MT-mTer and α-mTer-siRNA, 2 novel gene constructs that specifically target and co-opt murine telomerase activity within mouse prostate cancer cells. These constructs offer a significant advantage, as they can be used to investigate TI in immuno-competent mice that develop prostate cancer, thereby modeling actual human disease and testing TI-based therapies in a much more informative and authentic manner. No significant financial relationships to disclose.

scholarly journals CRISPR/Cas9-Mediated TERT Disruption in Cancer Cells

2020 ◽  
Vol 21 (2) ◽  
pp. 653 ◽  
Author(s):  
Luan Wen ◽  
Changzhi Zhao ◽  
Jun Song ◽  
Linyuan Ma ◽  
Jinxue Ruan ◽  
...  
Keyword(s):  
Cancer Cells ◽  
Tumor Cells ◽  
Gene Editing ◽  
Therapeutic Option ◽  
Telomerase Activity ◽  
Telomere Attrition ◽  
Tert Gene ◽  
Cancer Cell Survival

Mammalian telomere lengths are primarily regulated by telomerase, a ribonucleoprotein consisting of a reverse transcriptase (TERT) and an RNA subunit (TERC). TERC is constitutively expressed in all cells, whereas TERT expression is temporally and spatially regulated, such that in most adult somatic cells, TERT is inactivated and telomerase activity is undetectable. Most tumor cells activate TERT as a mechanism for preventing progressive telomere attrition to achieve proliferative immortality. Therefore, inactivating TERT has been considered to be a promising means of cancer therapy. Here we applied the CRISPR/Cas9 gene editing system to target the TERT gene in cancer cells. We report that disruption of TERT severely compromises cancer cell survival in vitro and in vivo. Haploinsufficiency of TERT in tumor cells is sufficient to result in telomere attrition and growth retardation in vitro. In vivo, TERT haploinsufficient tumor cells failed to form xenograft after transplantation to nude mice. Our work demonstrates that gene editing-mediated TERT knockout is a potential therapeutic option for treating cancer.

BMP4 signaling induces senescence and modulates the oncogenic phenotype of A549 lung adenocarcinoma cells

2004 ◽  
Vol 286 (1) ◽  
pp. L81-L86 ◽  
Author(s):  
S. Buckley ◽  
W. Shi ◽  
B. Driscoll ◽  
A. Ferrario ◽  
K. Anderson ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cancer Cells ◽  
Transforming Growth Factor ◽  
A549 Cells ◽  
Telomerase Activity ◽  
Lung Cancer Cells ◽  
Senescent Phenotype ◽  
A549 Lung

Lung cancer is the most common visceral malignancy in males, with rapidly increasing incidence in females, and a devastatingly poor prognosis. Transforming growth factor (TGF)-β has been shown to induce senescence in A549 lung cancer cells, and both TGF-β and bone morphogenetic protein (BMP) 2 can suppress the transformed phenotype of A549 cells in vitro. We examined the effects of BMP4, another member of the TGF-β superfamily, on specific oncogenic properties of A549 cancer cells. When A549 cancer cells were treated continuously with 100 ng/ml of BMP4, a senescent phenotype was observed after 2 wk of treatment. The BMP-treated cells appeared larger than untreated cells, grew more slowly, had more senescence-associated β-galactosidase activity, and had less telomerase activity, as measured by the telomeric repeat amplification protocol assay. Invasion through Engelbreth Holm-Swarm matrix was inhibited in the senescent cell population. Senescent BMP4-treated cells had lower ERK activation, VEGF expression, and Bcl2 expression than wild-type cells, consistent with a less proliferative, less angiogenic phenotype with increased susceptibility to death by apoptosis. BMP4 treatment also resulted in sustained elevation of Smad1. In vivo xenograft studies in the flanks of nude mice confirmed that the BMP-treated cells were significantly less tumorigenic than untreated cells. Direct overexpression of Smad1 using adenoviral constructs resulted in cell death within 5 days. These studies suggest that BMP4 pathway signaling can induce senescence and thus negatively regulate the growth of A549 lung cancer cells.

Telomerase antisense inhibition for the proliferation of endometrial cancer in vitro and in vivo

2006 ◽  
Vol 16 (6) ◽  
pp. 1987-1993 ◽  
Author(s):  
X. J. Chen ◽  
W. Zheng ◽  
L. L. Chen ◽  
Z. B. Chen ◽  
S. Q. Wang
Keyword(s):  
Endometrial Cancer ◽  
Cancer Cells ◽  
Cancer Cell Line ◽  
Telomerase Activity ◽  
High Dose ◽  
Dependent Manner ◽  
Antitumor Effects ◽  
Telomerase Inhibitors

The objective of this study was to investigate the antitumor effect of antisense telomerase oligodeoxynucleotides to endometrial cancer cells in vitro and in vivo. Antisense oligodeoxynucleotides (ODNs) against the human telomerase transcripatse (hTERT) synthesized to serve as telomerase inhibitors. Reverse transcription–polymerase chain reaction and 3-[4,5-dimethylthiazol-2yl]-2,5-diphenyltetrazolium bromide (MTT) assay were used to test the expression of hTERT messengerRNA (mRNA) and inhibition of cell proliferation in vitro. In vivo, antitumor effects of ODNs or combined with cisplatin were evaluated in endometrial cancer xenograft. Telomerase activity was tested by telomeric repeat amplification protocol. Antisense ODNs could inhibit proliferation of human endometrial cancer cells (HEC-1-A) in vitro, and downregulate the expression hTRET mRNA in a dose- and period-dependent manner. The tumor growth inhibitory rate of low- and high-dose ODNs were 34.20% and 89.21%, and combined group was 75.30%. Telomerase activity was downregulated to 87.32% compared to the control in the ODNs-treated xenograft tumors. Antisense oligonucleotides of hTERT effectively inhibit the growth of endometrial cancer cell line. Telomerase inhibitor might be a new strategy for chemotherapy or chemoprevention in endometrial cancer.

Telomerase is regulated by protein kinase C-ζ in human nasopharyngeal cancer cells

2001 ◽  
Vol 355 (2) ◽  
pp. 459-464 ◽  
Author(s):  
Cheng-Chou YU ◽  
Shi-Ching LO ◽  
Tzu-Chien V. WANG
Keyword(s):  
Protein Kinase C ◽  
Protein Kinase ◽  
Cancer Cells ◽  
Nasopharyngeal Cancer ◽  
Telomerase Activity ◽  
Detectable Effect ◽  
Kinase C ◽  
Pkc Ζ

Telomerase, a specialized ribonucleoprotein reverse transcriptase that directs the synthesis of telomeric DNA, is repressed in normal human somatic cells, but is activated in most cancers. Little is known concerning how telomerase activity is activated and maintained in cancer cells. We have shown previously that inhibition of protein kinase C (PKC) decreases the telomerase activity of human nasopharyngeal carcinoma (NPC) cells. Here, we provide evidence that the decrease of telomerase activity by PKC inhibition is not mediated by transcriptional down-regulation of hTERT, the catalytic protein of human telomerase. In vitro phosphorylation studies revealed that exogenous addition of PKC-α, -βI, -δ or -ζ led to restoration of telomerase activity in the crude extracts of PKC-inhibited NPC cells. However, depletion of PKC-α and -βI in vivo had no detectable effect on the telomerase activity of NPC cells. Using antisense oligonucleotides against individual PKC isotypes, we observed that telomerase activity was inhibited only by the antisense oligonucleotide against PKC-ζ but not by those against PKC-α, -βI or -δ. Taken together, these data demonstrate that PKC participates in the regulation of telomerase activity by direct or indirect phosphorylation of telomerase proteins, and that PKC-ζ is the PKC isotype that functions in vivo in the NPC cells.

scholarly journals Locked nucleic acid-inhibitor of miR-205 decreases endometrial cancer cells proliferation in vitro and in vivo

Oncotarget ◽  
2016 ◽  
Vol 7 (45) ◽  
pp. 73651-73663 ◽  
Author(s):  
Anna Torres ◽  
Joanna Kozak ◽  
Agnieszka Korolczuk ◽  
Dominika Rycak ◽  
Paulina Wdowiak ◽  
...  
Keyword(s):  
Endometrial Cancer ◽  
Nucleic Acid ◽  
Cancer Cells ◽  
Locked Nucleic Acid ◽  
Acid Inhibitor ◽  
Proliferation In Vitro

In Vitro and In Vivo Antitumor Efficacy of Docetaxel and Sorafenib Combination in Human Pancreatic Cancer Cells

2010 ◽  
Vol 999 (999) ◽  
pp. 1-11
Author(s):  
P. Ulivi ◽  
C. Arienti ◽  
W. Zoli ◽  
M. Scarsella ◽  
S. Carloni ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Cancer Cells ◽  
Antitumor Efficacy ◽  
Human Pancreatic Cancer ◽  
Pancreatic Cancer Cells

A Novel Triazole Derivative Drug Presenting In Vitro and In Vivo Anticancer Properties

2018 ◽  
Vol 18 (17) ◽  
pp. 1483-1493
Author(s):  
Ricardo Imbroisi Filho ◽  
Daniel T.G. Gonzaga ◽  
Thainá M. Demaria ◽  
João G.B. Leandro ◽  
Dora C.S. Costa ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Cell Line ◽  
Cancer Cell ◽  
Cancer Cell Line ◽  
Hepatic Function ◽  
Anticancer Properties ◽  
Mcf 7

Background: Cancer is a major cause of death worldwide, despite many different drugs available to treat the disease. This high mortality rate is largely due to the complexity of the disease, which results from several genetic and epigenetic changes. Therefore, researchers are constantly searching for novel drugs that can target different and multiple aspects of cancer. Experimental: After a screening, we selected one novel molecule, out of ninety-four triazole derivatives, that strongly affects the viability and proliferation of the human breast cancer cell line MCF-7, with minimal effects on non-cancer cells. The drug, named DAN94, induced a dose-dependent decrease in MCF-7 cells viability, with an IC50 of 3.2 ± 0.2 µM. Additionally, DAN94 interfered with mitochondria metabolism promoting reactive oxygen species production, triggering apoptosis and arresting the cancer cells on G1/G0 phase of cell cycle, inhibiting cell proliferation. These effects are not observed when the drug was tested in the non-cancer cell line MCF10A. Using a mouse model with xenograft tumor implants, the drug preventing tumor growth presented no toxicity for the animal and without altering biochemical markers of hepatic function. Results and Conclusion: The novel drug DAN94 is selective for cancer cells, targeting the mitochondrial metabolism, which culminates in the cancer cell death. In the end, DAN94 has been shown to be a promising drug for controlling breast cancer with minimal undesirable effects.

Carbon dots derived from Fusobacterium nucleatum for intracellular determination of Fe3+ and bioimaging both in vitro and in vivo

2021 ◽  
Author(s):  
Lijuan Liu ◽  
Shengting Zhang ◽  
Xiaodan Zheng ◽  
Hongmei Li ◽  
Qi Chen ◽  
...  
Keyword(s):  
Carbon Dots ◽  
Fusobacterium Nucleatum ◽  
Living Cells ◽  
First Time ◽  
Fluorescent Carbon Dots ◽  
Fluorescent Carbon

Fusobacterium nucleatum has been employed for the first time to synthesize fluorescent carbon dots which could be applied for the determination of Fe3+ ions in living cells and bioimaging in vitro and in vivo with excellent biocompatibility.

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