Differential protein expression in MCF7 breast cancer cells transfected with ErbB2, neomycin resistance and luciferase plus yellow fluorescent protein

PROTEOMICS ◽  
2004 ◽  
Vol 4 (7) ◽  
pp. 2175-2183 ◽  
Author(s):  
Daojing Wang ◽  
Ronald H. Jensen ◽  
Katherine E. Williams ◽  
Maria G. Pallavicini
2020 ◽  
Author(s):  
Kenneth F. Fuh ◽  
Robert D. Shepherd ◽  
Jessica S. Withell ◽  
Brayden K. Kooistra ◽  
Kristina D Rinker

Abstract Background: Fluid forces are an integral part of the tumor microenvironment through all phases of development and progression. However, it is not well understood how these forces affect key steps in the progression of breast cancer of Epithelial-to-Mesenchymal Transition (EMT) and adhesion to vascular wall endothelial cells. EMT is associated with the progression of most carcinomas through induction of new transcriptional programs within affected epithelial cells, resulting in cells becoming more motile and adhesive to endothelial cells.Methods: MDA-MB-231, SK-BR-3, BT-474, and MCF-7 cells and normal Human Mammary Epithelial Cells (HMECs) were exposed to fluid flow in a parallel-plate bioreactor system. Changes in gene expression were quantified using microarrays and qPCR, gene-gene interactions were elucidated using network analysis, and key modified genes were examined in clinical datasets. Changes in protein expression of key EMT markers between chemically induced EMT and flow-exposed cells were compared in immunocytochemistry assays. Finally, the ability of flow-stimulated and unstimulated cancer cells to adhere to an endothelial monolayer was evaluated in flow and static adhesion experiments.Results: Fluid flow stimulation resulted in upregulation of EMT inducers and downregulation of repressors. Specifically, Vimentin and Snail were upregulated both at the gene and protein expression levels in flow stimulated HMECs, suggesting progression towards an EMT phenotype. Flow-induced overexpression of a panel of cell adhesion genes was also observed. Network analysis revealed genes involved in cell flow responses including FN1, PLAU, and ALCAM. When evaluated in clinical datasets, overexpression of FN1, PLAU, and ALCAM was observed in patients with most subtypes of breast cancer. We also observed increased adhesion of flow-stimulated breast cancer cells compared to unstimulated controls, suggesting an increased potential to form secondary tumors at metastatic sites. Conclusions: This study shows that prolonged fluid force exposure on the order of 1 Pa promotes EMT and adhesion of breast cancer cells to an endothelial monolayer. Further, identified biomarkers were distinctly expressed in patient populations. A better understanding of how biophysical forces such as shear stress affect cellular processes involved in metastatic progression of breast cancer is important for identifying new molecular markers for disease progression, and for predicting metastatic risk.


2019 ◽  
Author(s):  
Xi Qiao ◽  
Ying Liu ◽  
Maria Llamazares Prada ◽  
Abhishekh Gupta ◽  
Alok Jaiswal ◽  
...  

AbstractMYC protein expression has to be tightly controlled to allow for maximal cell proliferation without inducing apoptosis. Here we discover UBR5 as a novel MYC ubiquitin ligase and demonstrate how it functions as a molecular rheostat to prevent excess accumulation of MYC protein. UBR5 effects on MYC protein stability are independent on N-terminal FBW7 degron of MYC. Endogenous UBR5 inhibition induces MYC protein expression and activates MYC target genes. Moreover, UBR5 governs MYC-dependent phenotypes in vivo in Drosophila. In cancer cells, UBR5-mediated MYC protein suppression diminishes cell killing activity of cancer therapeutics. Further, we demonstrate that UBR5 dominates MYC protein expression at the single-cell level in human basal-type breast cancer tissue. Myc and Ubr5 are co-amplified in MYC-driven human cancer types, and UBR5 controls MYC-mediated apoptotic threshold in co-amplified basal type breast cancer cells. In summary, UBR5 is a novel MYC ubiquitin ligase and an endogenous rheostat for MYC protein expression in vivo. Clinically, expression of UBR5 may be important for protection of breast cancer cells from drug-induced, and MYC-dependent, apoptosis.


2020 ◽  
Vol 2020 ◽  
pp. 1-12 ◽  
Author(s):  
Xiao-jun Gou ◽  
Huan-huan Bai ◽  
Li-wei Liu ◽  
Hong-yu Chen ◽  
Qi Shi ◽  
...  

Objective. To explore the ability of asiatic acid to interfere with the invasion and proliferation of breast cancer cells by inhibiting WAVE3 expression and activation through the PI3K/AKT signaling pathway. Methods. The MDA-MB-231 cells with strong invasiveness were screened by transwell assay, and plasmids with high expression of WAVE3 were constructed for transfection. The transfection effect and protein expression level of plasmids were verified by PCR and WB. The effects of asiatic acid on cell proliferation and invasion were investigated by flow cytometry. The xenografted tumor models in nude mice were established to study the antitumor activity of asiatic acid. Results. Asiatic acid significantly inhibited the activity of MDA-MB-231 cells, and the expression level of WAVE3 increased significantly in the tissue of ductal carcinoma in situ and was lower than that in the metastasis group. After plasmid transfection, the mRNA and protein expression of WAVE3 increased significantly in the cells. Asiatic acid at different concentrations had an impact on cell apoptosis and invasion and could significantly inhibit the expression of WAVE3, P53, p-PI3K, p-AKT, and other proteins. The T/C(%) of asiatic acid (50 mg/kg) for MDA-MB-231(F10) xenografted tumor in nude mice was 46.33%, with a tumor inhibition rate of 59.55%. Asiatic acid could significantly inhibit the growth of MDA-MB-231 (F10) xenografted tumors in nude mice (p<0.05). Conclusions. Asiatic acid interferes with the ability of breast cancer cells to invade and proliferate by inhibiting WAVE3 expression and activation and the mechanism of action may be related to the PI3K/AKT signaling pathway.


Nutrients ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 865 ◽  
Author(s):  
Daniel Gabriel Pons ◽  
Carmen Moran ◽  
Marina Alorda-Clara ◽  
Jordi Oliver ◽  
Pilar Roca ◽  
...  

Selenium is a micronutrient which is found in many foods, with redox status modulation activity. Our aim was to evaluate the effects of two chemical forms of selenoamino acids, Seleno-L-methionine and Seleno-L-cystine (a diselenide derived from selenocysteine), at different concentrations on cell viability, hydrogen peroxide production, antioxidant enzymes, UCP2 protein expression, as well as lipid and protein oxidative damage in MCF-7 breast cancer cells. Results showed that Seleno-L-methionine did not cause an increase in hydrogen peroxide production at relatively low concentrations, accompanied by a rise in the antioxidant enzymes catalase and MnSOD, and UCP2 protein expression levels. Furthermore, a decrease in protein and lipid oxidative damage was observed at 10 µM concentration. Otherwise, Seleno-L-cystine increased hydrogen peroxide production from relatively low concentrations (100 nM) to a large increase at high concentrations. Moreover, at 10 µM, Seleno-L-cystine decreased UCP2 and MnSOD protein expression. In conclusion, the chemical form of selenoamino acid and their incorporation to selenoproteins could affect the regulation of the breast cancer cell redox status. Taken together, the results obtained in this study imply that it is important to control the type of selenium-enriched nutrient consumption, taking into consideration their composition and concentration.


2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Sylvie Rodrigues-Ferreira ◽  
Marina Morel ◽  
Rosana I. Reis ◽  
Françoise Cormier ◽  
Véronique Baud ◽  
...  

Recent studies have highlighted the AT1 receptor as a potential therapeutic target in breast cancer, while the role of the AT2 subtype in this disease has remained largely neglected. The present study describes the generation and characterization of a new cellular model of human invasive breast cancer cells (D3H2LN-AT2) stably expressing high levels of Flag-tagged human AT2 receptor (Flag-hAT2). These cells exhibit high-affinity binding sites for AngII, and total binding can be displaced by the AT2-selective antagonist PD123319 but not by the AT1-selective antagonist losartan. Of interest, high levels of expression of luciferase and green fluorescent protein make these cells suitable for bioluminescence and fluorescence studies in vitro and in vivo. We provide here a novel tool to investigate the AT2 receptor functions in breast cancer cells, independently of AT1 receptor activation.


2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e22035-e22035
Author(s):  
C. F. Singer ◽  
G. Hudelist ◽  
E. Fuchs ◽  
W. Köstler ◽  
A. Fink-Retter ◽  
...  

e22035 Background: HER-2 amplification and consecutive overexpression is a predictor for poor prognosis in breast cancer patients. In addition, incomplete resection of HER2 overexpressing tumors leads to increased proliferation of residual breast cancer cells. While the local release of cytokines is thought to be responsible for the malignant behaviour of remaining tumor tissue, the exact mechanism is still unknown. Methods: We have analyzed EGFR, activated (p)EGFR, and activated (p)HER2 protein expression in HER2 overexpressing and in non-HER2 overexpressing tumors from patients who underwent breast surgery and consecutive reexcision for involved margins, and compared expression levels by IHC. Results: While overall HER2 protein expression in the initial and the reexcised sample were comparable, we observed an increase in pHER2 in DCIS in both, HER2 overexpressing (16/21 vs 24/24; p=0.018, Chi Square test) and non-HER2 overexpressing tumors (3/28 vs 5/12; p=0.025, Chi Square test). pHER2 was not increased in invasive tumors, regardless on whether the samples had been taken from a HER2 overexpressing (9/25 vs 6/17; p=0.261, Chi Square test), or a non-HER2 overexpressing tumor (1/27 vs 0/8; p=0.581, Chi Square test). EGFR expression was only detected in 1/47 HER2 overexpressing primary tumors and 2/48 non-HER2 overexpressing tumors, and was undetectable in reexcised specimen. Conclusions: Taken together, we have demonstrated an increase in HER2 receptor activation in incompletely resected preinvasive breast cancer. We hypothesize that receptor phosphorylation is caused by growth factor stimulation in response to intraoperative tissue damage, and perioperative inhibition of specific cytokines could become a promising therapeutic strategy. No significant financial relationships to disclose.


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