scholarly journals Fluoride at Mitogenic Doses Induces a Sustained Activation of p44mapk, but Not p42mapk, in Human TE85 Osteosarcoma Cells*

1997 ◽  
Vol 82 (4) ◽  
pp. 1126-1135
Author(s):  
Li-Wha Wu ◽  
Hyun Koo Yoon ◽  
David J. Baylink ◽  
Lee M. Graves ◽  
K.-H. William Lau
Keyword(s):  
Cell Proliferation ◽  
Steady State ◽  
Specific Activity ◽  
Bone Cell ◽  
Time Dependent ◽  
Dependent Manner ◽  
Osteosarcoma Cells ◽  
Fluoride Treatment ◽  
Phosphorylation Level ◽  
Tyrosyl Phosphorylation

Abstract Fluoride, at micromolar concentrations, stimulates bone cell proliferation in vitro. In this study, we sought to test whether fluoride at mitogenic doses increases the tyrosyl phosphorylation level and specific activity of a mitogen-activated protein kinase (MAPK) in human TE85 osteosarcoma cells. Analysis by immunoprecipitation with antiphosphotyrosine antibody followed by Western analysis using an anti-pan extracellular signal-regulated kinase antibody revealed that fluoride at the optimal mitogenic dose (i.e. 100 μmol/L) induced a time-dependent increase in the steady state tyrosyl phosphorylation level of p44mapk, but not p42mapk, with the maximal increase (4- to 13-fold) after 1–3 h fluoride treatment. The effect was sustained in that a 9-fold increase was seen after 12 h of the fluoride treatment. The sustained nature of the effect is consistent with an inhibition of dephosphorylation rather than a direct stimulation of phosphorylation. The fluoride effect on the tyrosyl phosphorylation level of p44mapk was dose dependent, with the optimal dose being 100μ mol/L fluoride. The mitogenic dose of fluoride also increased the specific activity and the in-gel kinase activity of p44mapk, but not that of p42mapk, in a time-dependent manner similar to the effect on the p44mapk tyrosyl phosphorylation level. Fluoride at the same micromolar doses did not increase cell proliferation, tyrosyl phosphorylation, or specific activity of any MAPK in human skin foreskin fibroblasts, which are fluoride-nonresponsive cells. Consistent with the interpretation that the effect of fluoride on the steady state tyrosyl phosphorylation level of p44mapk is a consequence of an inhibition of a phosphotyrosyl phosphatase (PTP), mitogenic doses of orthovanadate, a bone cell mitogen and a PTP inhibitor, also increased the steady state tyrosyl phosphorylation level of p44mapk, but not p42mapk, in a time-dependent sustained manner similar to that observed with fluoride. Together, these findings support the concept that inhibition of a PTP activity in bone cells could lead to an activation of MAPK activity.

scholarly journals Integrated analysis of potential pathways by which aloe-emodin induces the apoptosis of colon cancer cells

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Dongxiao Jiang ◽  
Shufei Ding ◽  
Zhujun Mao ◽  
Liyan You ◽  
Yeping Ruan
Keyword(s):  
Colon Cancer ◽  
Cell Proliferation ◽  
Cancer Cells ◽  
Caspase 3 ◽  
Time Dependent ◽  
Integrated Analysis ◽  
Dependent Manner ◽  
Colon Cancer Cells ◽  
Dapi Staining ◽  
Aloe Emodin

Abstract Background Colon cancer is a malignant gastrointestinal tumour with high incidence, mortality and metastasis rates worldwide. Aloe-emodin is a monomer compound derived from hydroxyanthraquinone. Aloe-emodin produces a wide range of antitumour effects and is produced by rhubarb, aloe and other herbs. However, the mechanism by which aloe-emodin influences colon cancer is still unclear. We hope these findings will lead to the development of a new therapeutic strategy for the treatment of colon cancer in the clinic. Methods We identified the overlapping targets of aloe-emodin and colon cancer and performed protein–protein interaction (PPI), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. In addition, we selected apoptosis pathways for experimental verification with cell viability, cell proliferation, caspase-3 activity, DAPI staining, cell cycle and western blotting analyses to evaluate the apoptotic effect of aloe-emodin on colon cancer cells. Results The MTT assay and cell colony formation assay showed that aloe-emodin inhibited cell proliferation. DAPI staining confirmed that aloe-emodin induced apoptosis. Aloe-emodin upregulated the protein level of Bax and decreased the expression of Bcl-2, which activates caspase-3 and caspase-9. Furthermore, the protein expression level of cytochrome C increased in a time-dependent manner in the cytoplasm but decreased in a time-dependent manner in the mitochondria. Conclusion These results indicate that aloe-emodin may induce the apoptosis of human colon cancer cells through mitochondria-related pathways.

scholarly journals Determinants of mRNA stability in Dictyostelium discoideum amoebae: differences in poly(A) tail length, ribosome loading, and mRNA size cannot account for the heterogeneity of mRNA decay rates.

1988 ◽  
Vol 8 (5) ◽  
pp. 1957-1969 ◽  
Author(s):  
R A Shapiro ◽  
D Herrick ◽  
R E Manrow ◽  
D Blinder ◽  
A Jacobson
Keyword(s):  
Steady State ◽  
Dictyostelium Discoideum ◽  
Mrna Decay ◽  
Decay Rates ◽  
Time Dependent ◽  
Translational Efficiency ◽  
Cdna Clones ◽  
Dependent Manner ◽  
Significant Difference ◽  
Kinetics Of

As an approach to understanding the structures and mechanisms which determine mRNA decay rates, we have cloned and begun to characterize cDNAs which encode mRNAs representative of the stability extremes in the poly(A)+ RNA population of Dictyostelium discoideum amoebae. The cDNA clones were identified in a screening procedure which was based on the occurrence of poly(A) shortening during mRNA aging. mRNA half-lives were determined by hybridization of poly(A)+ RNA, isolated from cells labeled in a 32PO4 pulse-chase, to dots of excess cloned DNA. Individual mRNAs decayed with unique first-order decay rates ranging from 0.9 to 9.6 h, indicating that the complex decay kinetics of total poly(A)+ RNA in D. discoideum amoebae reflect the sum of the decay rates of individual mRNAs. Using specific probes derived from these cDNA clones, we have compared the sizes, extents of ribosome loading, and poly(A) tail lengths of stable, moderately stable, and unstable mRNAs. We found (i) no correlation between mRNA size and decay rate; (ii) no significant difference in the number of ribosomes per unit length of stable versus unstable mRNAs, and (iii) a general inverse relationship between mRNA decay rates and poly(A) tail lengths. Collectively, these observations indicate that mRNA decay in D. discoideum amoebae cannot be explained in terms of random nucleolytic events. The possibility that specific 3'-structural determinants can confer mRNA instability is suggested by a comparison of the labeling and turnover kinetics of different actin mRNAs. A correlation was observed between the steady-state percentage of a given mRNA found in polysomes and its degree of instability; i.e., unstable mRNAs were more efficiently recruited into polysomes than stable mRNAs. Since stable mRNAs are, on average, "older" than unstable mRNAs, this correlation may reflect a translational role for mRNA modifications that change in a time-dependent manner. Our previous studies have demonstrated both a time-dependent shortening and a possible translational role for the 3' poly(A) tracts of mRNA. We suggest, therefore, that the observed differences in the translational efficiency of stable and unstable mRNAs may, in part, be attributable to differences in steady-state poly(A) tail lengths.

DHT and testosterone, but not DHEA or E2, differentially modulate IGF-I, IGFBP-2, and IGFBP-3 in human prostatic stromal cells

2006 ◽  
Vol 290 (5) ◽  
pp. E952-E960 ◽  
Author(s):  
Hanh Le ◽  
Julia T. Arnold ◽  
Kimberly K. McFann ◽  
Marc R. Blackman
Keyword(s):  
Prostate Cancer ◽  
Cell Proliferation ◽  
Mrna Expression ◽  
Protein Secretion ◽  
Stromal Cells ◽  
Stromal Cell ◽  
Time Dependent ◽  
Dependent Manner ◽  
Igf I ◽  
Igfbp 3

Prostate cancer is one of the four most common cancers in the United States, affecting one of six men. Increased serum levels of androgens and IGF-I are associated with an augmented risk of prostate cancer. Dihydrotestosterone (DHT) and testosterone (T) stimulate prostate cancer cell growth, development, and function, whereas the effects of DHT and T in prostate stromal cells, and of dehydroepiandrosterone (DHEA) in prostate cancer or stromal cells, are uncertain. We investigated the actions of DHT, T, DHEA, and estradiol (E2) on insulin-like growth factor (IGF)-I, IGF-II, IGF-I receptor (R), IGF-binding protein (IGFBP)-2, IGFBP-3, and IGFBP-5 in primary cultures of human prostatic stromal cells by assessing cell proliferation, mRNA expression, and protein secretion by MTT growth assay, quantitative real-time PCR, and ELISA, respectively. DHT and T each increased IGF-I (7-fold) and decreased IGFBP-3 (2-fold) mRNA expression and protein secretion in a dose- and time-dependent manner and increased IGFBP-2 (2-fold) mRNA in a dose- and time-dependent manner. DHEA and E2did not significantly alter these measures. Flutamide abolished the DHT-modulated increases in IGF-I and IGFBP-2, suggesting that the influences of DHT and T on these measures were androgen receptor mediated. None of the four steroids significantly affected IGF-IR, IGF-II, or IGFBP-5 mRNA levels or stromal cell proliferation. The effects of DHT on IGF-I, IGFBP-2, and IGFBP-3 were more pronounced in stromal cultures that did not express desmin. These data suggest that DHT and T promote prostate growth partly via modulation of the stromal cell IGF axis, with potential paracrine effects on prostate epithelial cells.

scholarly journals The Mechanism of Aloe-emodin in the Treatment of Colon Cancer based on Network Pharmacological Analysis

2020 ◽  
Author(s):  
Dongxiao Jiang ◽  
Shufei Ding ◽  
Zhujun Mao ◽  
Liyan You ◽  
yeping ruan
Keyword(s):  
Colon Cancer ◽  
Cell Proliferation ◽  
Cancer Cells ◽  
Caspase 3 ◽  
Time Dependent ◽  
Dependent Manner ◽  
Colon Cancer Cells ◽  
Dapi Staining ◽  
Wide Range ◽  
Aloe Emodin

Abstract Background: Colon cancer is a malignant gastrointestinal tumor with a high incidence, high mortality and high metastasis in the world. Aloe-emodin is a monomer compound derived from hydroxyanthraquinone. It makes a wide range of anti-tumor effects and exists in Rhubarb, Aloe, and other plants. However, the mechanism of aloe-emodin against colon cancer still not clear. Here, we predict the potential targets and mechanisms of aloe-emodin based on network pharmacology analysis. Methods: First, determine the intersection target of aloe-emodin and colon cancer, analyze and construct PPI, Gene Ontology, and KEGG pathway analysis. In addition, we selected apoptosis pathways for experimental verification including cell viability determination, cell proliferation, caspase-3 activity determination, DAPI staining, cell cycle determination and western blot to evaluate the apoptosis effect of aloe-emodin on colon cancer cells.Results: The MTT assay and cell colony experiment showed that AE inhibited cell proliferation (P<0.01). DAPI staining confirmed that AE induced apoptosis. AE activates caspase-3, caspase-9 and Bax and down-regulates the expression of Bcl-2. Furthermore, the expression level of cytochrome C protein increased in a time-dependent manner in the cytoplasm but fell in a time-dependent manner in the mitochondria.Conclusion: These results indicate that aloe-emodin may induce apoptosis of human colon cancer cells through mitochondrial related pathways.

Oroxylin A Shows Protective Effects on Biological Activity of Lipopolysaccharide Treated Human Periodontal Ligament Stem Cells

2019 ◽  
Vol 9 (10) ◽  
pp. 1362-1368
Author(s):  
Ting Wang ◽  
Xinqiang Liu ◽  
Chunmiao Jiang ◽  
Dapeng Ren ◽  
Yuli Gao ◽  
...  
Keyword(s):  
Stem Cells ◽  
Cell Proliferation ◽  
Biological Activity ◽  
Periodontal Ligament ◽  
Time Dependent ◽  
Dependent Manner ◽  
Protective Effects ◽  
Oroxylin A ◽  
Periodontal Ligament Stem Cells ◽  
Dose Dependent

The abnormal proliferation and apoptosis of human periodontal ligament stem cells (hPDLSCs) serves a crucial role in the development of periodontitis. Oroxylin A has shown protective effects in a variety of inflammatory diseases. The present study was aimed to investigate the effects of oroxylin A on lipopolysaccharide (LPS) treated hPDLSCs. In the present study, cells were exposed to different concentrations (10, 20, 40 uM) of oroxylin A for 24 h or 48 h, co-treated with LPS. The cell proliferation capacity was assessed using cell counting kit-8 (CCK-8), and the cell apoptosis was evaluated by flow cytometry. The Ki67 expression was measured using immunofluorescence and NO production was detected by enzyme linked immunosorbent assay (ELISA) respectively. Western blot analyses were used to investigate the level of cell proliferation related proteins (PCNA, CDK2 and p21) as well as NF-κB, I-κBα and downstream molecules iNOS, IL-6 and TNF-α. The results demonstrated that oroxylin A increased cell survival of LPS treated hPDLSCs in a dose-dependent and time-dependent manner. In addition, oroxylin A treatment inhibited cell apoptosis in hPDLSCs. Furthermore, the levels of NO, NF-κB, iNOS, IL-6 and TNF-α were significantly reduced. And the expression of Ki67, I-κBα, PCNA and CDK2 were significantly increased. Taken together, these findings indicate that oroxylin A promote proliferation and suppress apoptosis in a dose-dependent and time-dependent manner. Oroxylin A may affects LPS induced biological activity via inhibiting NF-κB activation and proinflammatory cytokines expression in hPDLSCs.

scholarly journals The proliferation and invasion of osteosarcoma are inhibited by miR-101 via targetting ZEB2

2019 ◽  
Vol 39 (2) ◽  
Author(s):  
Haopeng Lin ◽  
Xiaodong Zheng ◽  
Ting Lu ◽  
Yang Gu ◽  
Canhao Zheng ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Cell Lines ◽  
Molecular Mechanisms ◽  
Bone Cell ◽  
Luciferase Reporter ◽  
Osteosarcoma Cell ◽  
Osteosarcoma Cells ◽  
Human Osteosarcoma ◽  
Direct Target ◽  
Proliferation And Invasion

AbstractHaving a better grasp of the molecular mechanisms underlying carcinogenesis and progression in osteosarcoma would be helpful to find novel therapeutic targets. Different types of cancers have presented abnormal expression of miRNA-101 (miR-101). Nevertheless, we still could not figure out what expression of miR-101 in human osteosarcoma is and its biological function. Thus, we conducted the present study to identify its expression, function, and molecular mechanism in osteosarcoma. We detected the expression of miR-101 in osteosarcoma samples and cell lines. The effects of miR-101 on osteosarcoma cells’ proliferation and invasion were evaluated. Luciferase reporter assay was applied to identify the direct target of miR-101. Compared with adjacent normal specimens and normal bone cell line by using qPCR, the expression levels of miR-101 in osteosarcoma specimens and human osteosarcoma cell lines distinctly decreased. According to function assays, we found that overexpression of miR-101 significantly inhibited the cell proliferation and invasion in osteosarcoma cells. Moreover, we confirmed that zinc finger E-box binding homeobox 2 (ZEB2) was a direct target of miR-101. In addition, overexpression of ZEB2 could rescue the inhibition effect of proliferation and invasion induced by miR-101 in osteosarcoma cells. MiR-101 has been proved to be down-regulated in osteosarcoma and has the ability to suppress osteosarcoma cell proliferation and invasion by directly targetting ZEB2.

scholarly journals Induction of Apoptosis by Gluconasturtiin-Isothiocyanate (GNST-ITC) in Human Hepatocarcinoma HepG2 Cells and Human Breast Adenocarcinoma MCF-7 Cells

Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1240
Author(s):  
Asvinidevi Arumugam ◽  
Muhammad Din Ibrahim ◽  
Saie Brindha Kntayya ◽  
Nooraini Mohd Ain ◽  
Renato Iori ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Cell Death ◽  
Cell Lines ◽  
Chromatin Condensation ◽  
Time Dependent ◽  
Breast Adenocarcinoma ◽  
Dependent Manner ◽  
Human Breast ◽  
Human Breast Adenocarcinoma ◽  
Mcf 7

Gluconasturtiin, a glucosinolate present in watercress, is hydrolysed by myrosinase to form gluconasturtiin-isothiocyanate (GNST-ITC), which has potential chemopreventive effects; however, the underlying mechanisms of action have not been explored, mainly in human cell lines. The purpose of the study is to evaluate the cytotoxicity of GNST-ITC and to further assess its potential to induce apoptosis. GNST-ITC inhibited cell proliferation in both human hepatocarcinoma (HepG2) and human breast adenocarcinoma (MCF-7) cells with IC50 values of 7.83 µM and 5.02 µM, respectively. Morphological changes as a result of GNST-ITC-induced apoptosis showed chromatin condensation, nuclear fragmentation, and membrane blebbing. Additionally, Annexin V assay showed proportion of cells in early and late apoptosis upon exposure to GNST-ITC in a time-dependent manner. To delineate the mechanism of apoptosis, cell cycle arrest and expression of caspases were studied. GNST-ITC induced a time-dependent G2/M phase arrest, with reduction of 82% and 93% in HepG2 and MCF-7 cell lines, respectively. The same treatment also led to the subsequent expression of caspase-3/7 and -9 in both cells demonstrating mitochondrial-associated cell death. Collectively, these results reveal that GNST-ITC can inhibit cell proliferation and can induce cell death in HepG2 and MCF-7 cancer cells via apoptosis, highlighting its potential development as an anticancer agent.

scholarly journals PCB118-Induced Cell Proliferation Mediated by Oxidative Stress and MAPK Signaling Pathway in HELF Cells

Dose-Response ◽  
2018 ◽  
Vol 16 (1) ◽  
pp. 155932581775152 ◽  
Author(s):  
Muhammad Zaffar Hashmi ◽  
Ahmad Hasnain ◽  
Jabir Hussain Syed ◽  
Muhammad Tariq ◽  
Xiaomei Su ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cell Proliferation ◽  
Mapk Signaling ◽  
Time Dependent ◽  
Test Model ◽  
Dependent Manner ◽  
Toxicological Evaluation ◽  
Human Lung Fibroblast ◽  
Proliferative Effect ◽  
Extracellular Signal

The present study used human lung fibroblast (HELF) cells as a test model to evaluate the role of oxidative stress (OS) and extracellular signal-regulated kinases 1/2 (ERK1/2) protein in HELF cell proliferation exposed to PCB118. Results from 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide demonstrated that PCB118 at lower concentrations stimulated proliferation of HELF cell and abrogate proliferative effect at higher dose concentrations and in a time-dependent manner. Moreover, reactive oxygen species, malondialdehyde (MDA), and superoxide dismutase showed a significant increase at higher concentrations of PCB118 than the lower concentrations with the passage of time. Antioxidant enzymes such as glutathione peroxidase exhibited decreasing trends in dose- and time-dependent manner. Lipid peroxidation assay resulted in a significant increase in MDA level in PCB118-treated HELF cells compared with controls, suggesting that OS plays a key role in PCB118-induced toxicity. Comet assay indicated a significant increase in genotoxicity at higher concentrations of PCB118 exposure than the lower concentrations. It was found that PCB118 showed expression of ERK1/2 protein after 4 hours, while after 48 hours, the protein expression was less, indicating PCB toxicity to MAPK protein of HELF cell. Oxidative stress, ERK1/2, and HELF cell proliferation exhibited correlation. The results will elaborate toxicological evaluation of PCB118 to HELF cells and will help to develop drug for PCB-induced diseases.

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