scholarly journals GLUTATHIONE AND GLUTAREDOXIN IN ROSCOVITINE-MEDIATED INHIBITION OF BREAST CANCER CELL PROLIFERATION

2017 ◽  
Vol 72 (4) ◽  
pp. 261-267 ◽  
Author(s):  
E. V. Shakhristova ◽  
E. A. Stepovaya ◽  
O. L. Nosareva ◽  
E. V. Rudikov ◽  
V. V. Novitsky

Background: Breast tumors are number one cause of cancer morbidity and mortality among women around the world, and Russia is not an exception. Many proteins that control proliferation of immortalized cells are redox-regulated, which is essential for modulating cellular proliferative activity, especially during tumor growth. Studying the role of glutaredoxin and glutathione in cell cycle phase distribution will allow not only to identify the molecular targets regulating cell proliferation, but also to develop methods of diagnosis and targeted therapy of socially sensitive diseases, including breast cancer, in the future.Aims: To evaluate the role of glutathione and glutaredoxin in the molecular mechanisms regulating MCF-7 breast cancer cell proliferation under the effects of roscovitine, a cyclin-dependent protein kinase inhibitor.Materials and methods: The MCF-7 cell line (human breast adenocarcinoma) was used in the study. The cell culture was incubated in the presence and absence of roscovitine in the final concentration of 20 µmol for 18 h. The production of reactive oxygen species, the distribution of cells between cell cycle phases and the amount of Annexin V positive cells were determined using flow cytometry. The concentrations of total, reduced and oxidized glutathione, protein SH groups and protein-bound glutathione were measured by spectrophotometry. The levels of glutaredoxin, cyclin E and cyclin-dependent protein kinases were estimated by Western blotting with monoclonal antibodies.Results: The effects of roscovitine in the MCF-7 cells resulted in cell cycle arrest in G2/М phases with the decreased levels of cyclin E and cyclin-dependent protein kinase 2. It was accompanied by activation of programmed cell death. In tumor cells incubated in the presence of roscovitine, oxidative stress was triggered, which was accompanied by the elevated generation of reactive oxygen species, the decrease in the concentration of reduced glutathione, and the rise in the level of glutaredoxin. It contributed to the increase in protein glutathionylation against the backdrop of the decreased SH group concentration.Conclusions: Breast cancer cell proliferation under the effects of roscovitine is reduced following not only the decrease in the cyclin level and cyclin-dependent protein kinase activity, but also the shift in the intracellular oxidant/antioxidant ratio. Roscovitine-induced oxidative stress in the MCF-7 cells contributed to protein glutathionylation with the changes in the protein structure and functions. It results in impaired cell cycle progression, indicating a possibility to regulate cellular proliferation through modulating functional properties of redox-dependent proteins using the glutathione/glutaredoxin system.

2006 ◽  
Vol 114 (1) ◽  
pp. 100-105 ◽  
Author(s):  
Marleen Maras ◽  
Caroline Vanparys ◽  
Frederik Muylle ◽  
Johan Robbens ◽  
Urs Berger ◽  
...  

Endocrinology ◽  
2017 ◽  
Vol 158 (12) ◽  
pp. 4218-4232 ◽  
Author(s):  
Chikayo Iwaya ◽  
Takashi Nomiyama ◽  
Shiho Komatsu ◽  
Takako Kawanami ◽  
Yoko Tsutsumi ◽  
...  

Abstract Incretin therapies have received much attention because of their tissue-protective effects, which extend beyond those associated with glycemic control. Cancer is a primary cause of death in patients who have diabetes mellitus. We previously reported antiprostate cancer effects of the glucagonlike peptide-1 (GLP-1) receptor (GLP-1R) agonist exendin-4 (Ex-4). Breast cancer is one of the most common cancers in female patients who have type 2 diabetes mellitus and obesity. Thus, we examined whether GLP-1 action could attenuate breast cancer. GLP-1R was expressed in human breast cancer tissue and MCF-7, MDA-MB-231, and KPL-1 cell lines. We found that 0.1 to 10 nM Ex-4 significantly decreased the number of breast cancer cells in a dose-dependent manner. Although Ex-4 did not induce apoptosis, it attenuated breast cancer cell proliferation significantly and dose-dependently. However, the dipeptidyl peptidase-4 inhibitor linagliptin did not affect breast cancer cell proliferation. When MCF-7 cells were transplanted into athymic mice, Ex-4 decreased MCF-7 tumor size in vivo. Ki67 immunohistochemistry revealed that breast cancer cell proliferation was significantly reduced in tumors extracted from Ex-4-treated mice. In MCF-7 cells, Ex-4 significantly inhibited nuclear factor κB (NF-κB ) nuclear translocation and target gene expression. Furthermore, Ex-4 decreased both Akt and IκB phosphorylation. These results suggest that GLP-1 could attenuate breast cancer cell proliferation via activation of GLP-1R and subsequent inhibition of NF-κB activation.


2012 ◽  
Vol 6 ◽  
pp. BCBCR.S9592 ◽  
Author(s):  
Hui Yu ◽  
Sumathy Mohan ◽  
Mohan Natarajan

Tumors require blood supply to survive, grow, and metastasize. This involves the process of angiogenesis signaling for new blood vessel growth into a growing tumor mass. Understanding the mechanism of the angiogenic signaling pathway and neovascularization for breast cancer cell proliferation and growth would help to develop molecular interventions and achieve disease free survival. Our hypothesis is that the surviving cancer cell(s) after radiotherapy can initiate angiogenic signaling pathway in the neighboring endothelial cells resulting in neovascularization for breast cancer cell growth. The angiogenic signaling pathway is initiated by angiogenic factors, VEGF and FGF-2, through activation of a transcriptional regulator NF-κB, which in turn is triggered by therapeutic doses of radiation exposure Human breast adenocarcinoma cells (MCF-7 cells) were exposed to Cesium-137 (137Cs) γ rays to a total dose of 2 Gy at a dose rate of 1.03 Gy/min. The results of mobility shift assay showed that radiation at clinical doses (2 Gy) could induce NF-κB DNA-binding activity. Then, we examined the communication of angiogenic signals from irradiated MCF-7 cells to vascular endothelial cells. At the protein level, the western blot showed induction of angiogenic factors VEGF and FGF-2 in MCF-7 cells irradiated with 2 Gy. Inhibition of NF-κB activation attenuated VEGF and FGF-2 levels. These factors are secreted into the medium. The levels of VEGF and FGF-2 in the extra cellular medium were both increased, after 2 Gy exposures. We also observed corresponding expression of VEGFR2 and FGFR1 in non-irradiated endothelial cells that were co-cultured with irradiated MCF-7 cells. In support of this, in vitro tube formation assays provided evidence that irradiated MCF-7 cells transmit signals to potentiate cultured non-irradiated endothelial cells to form tube networks, which is the hallmark of neovascularization. Inhibition of NF-κB activation attenuated irradiated MCF-7-induced tube network formation. The data provide evidence that the radiation exposure is responsible for tumor growth and maintenance by inducing an angiogenic signaling pathway through activation of NF-κB.


2020 ◽  
Vol 10 (8) ◽  
pp. 1193-1198
Author(s):  
Siyi Li ◽  
Hongjuan Peng ◽  
Jianwen Li

Epithelial membrane protein 3 (EMP3) regulates cell proliferation, differentiation, and apoptosis. Bioinformatics analysis revealed that miR-765 had complimentary sequence with the 3 -URT of EMP3 mRNA. miR-765 regulates EMP3 and influences breast cancer cell behaviors. However, it is unclear whether this regulation plays a role in affecting drug resistance. Our study assessed miR765's role in EMP3 expression and adriamycin (ADM) resistance of breast cancer. ADM resistant cell line MCF-7/ADM was established and assigned into miR-NC group, miR-765 mimic group, siRNA-NC group, and siRNA-EMP3 group followed by analysis of cell proliferation and apoptosis. miR-765 targets EMP3. The miR-765 level and apoptosis rate in MCF-7/ADM cells were significantly lower, while EMP3 level and cell proliferation were higher than MCF-7 cells. miR-765 mimic or siRNA-EMP3 significantly downregulated EMP3, weakened cell proliferation, increased apoptosis, and decreased ADM resistance. MiR-765 and EMP3 involves in ADM resistance of breast cancer cells. Up-regulation of miR-765 inhibits breast cancer cell proliferation and reduces ADM resistance via regulating EMP3.


Sign in / Sign up

Export Citation Format

Share Document