scholarly journals CGRRF1, a growth suppressor, regulates EGFR ubiquitination in breast cancer

2019 ◽  
Vol 21 (1) ◽  
Author(s):  
Yu-Ju Lee ◽  
Shiuh-Rong Ho ◽  
Joshua D. Graves ◽  
Yang Xiao ◽  
Shixia Huang ◽  
...  

Abstract Background CGRRF1 is a growth suppressor and consists of a transmembrane domain and a RING-finger domain. It functions as a RING domain E3 ubiquitin ligase involved in endoplasmic reticulum-associated degradation. The expression of CGRRF1 is decreased in cancer tissues; however, the role of CGRRF1 in breast cancer and the mechanism(s) of its growth suppressor function remain to be elucidated. Methods To investigate whether CGRRF1 inhibits the growth of breast cancer, we performed MTT assays and a xenograft experiment. Tumors harvested from mice were further analyzed by reverse phase protein array (RPPA) analysis to identify potential substrate(s) of CGRRF1. Co-immunoprecipitation assay was used to verify the interaction between CGRRF1 and its substrate, followed by in vivo ubiquitination assays. Western blot, subcellular fractionation, and reverse transcription quantitative polymerase chain reaction (qRT-PCR) were performed to understand the mechanism of CGRRF1 action in breast cancer. Publicly available breast cancer datasets were analyzed to examine the association between CGRRF1 and breast cancer. Results We show that CGRRF1 inhibits the growth of breast cancer in vitro and in vivo, and the RING-finger domain is important for its growth-inhibitory activity. To elucidate the mechanism of CGRRF1, we identified EGFR as a new substrate of CGRRF1. CGRRF1 ubiquitinates EGFR through K48-linked ubiquitination, which leads to proteasome degradation. In addition to regulating the stability of EGFR, knockout of CGRRF1 enhances AKT phosphorylation after EGF stimulation. By analyzing the breast cancer database, we found that patients with low CGRRF1 expression have shorter survival. As compared to normal breast tissues, the mRNA levels of CGRRF1 are lower in breast carcinomas, especially in HER2-positive and basal-like breast cancers. We further noticed that CGRRF1 promoter methylation is increased in breast cancer as compared to that in normal breast tissue, suggesting that CGRRF1 is epigenetically modified in breast cancer. Treatment of 5-azactidine and panobinostat restored CGRRF1 expression, supporting that the promoter of CGRRF1 is epigenetically modified in breast cancer. Since 5-azactidine and panobinostat can increase CGRRF1 expression, they might be potential therapies for breast cancer treatment. Conclusion We demonstrated a tumor-suppressive function of CGRRF1 in breast cancer and identified EGFR as its target.

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Farnaz Dabbagh Moghaddam ◽  
Iman Akbarzadeh ◽  
Ehsan Marzbankia ◽  
Mahsa Farid ◽  
Leila khaledi ◽  
...  

Abstract Background Melittin, a peptide component of honey bee venom, is an appealing candidate for cancer therapy. In the current study, melittin, melittin-loaded niosome, and empty niosome had been optimized and the anticancer effect assessed in vitro on 4T1 and SKBR3 breast cell lines and in vivo on BALB/C inbred mice. "Thin-layer hydration method" was used for preparing the niosomes; different niosomal formulations of melittin were prepared and characterized in terms of morphology, size, polydispersity index, encapsulation efficiency, release kinetics, and stability. A niosome was formulated and loaded with melittin as a promising drug carrier system for chemotherapy of the breast cancer cells. Hemolysis, apoptosis, cell cytotoxicity, invasion and migration of selected concentrations of melittin, and melittin-loaded niosome were evaluated on 4T1 and SKBR3 cells using hemolytic activity assay, flow cytometry, MTT assay, soft agar colony assay, and wound healing assay. Real-time PCR was used to determine the gene expression. 40 BALB/c inbred mice were used; then, the histopathology, P53 immunohistochemical assay and estimate of renal and liver enzyme activity for all groups had been done. Results This study showed melittin-loaded niosome is an excellent substitute in breast cancer treatment due to enhanced targeting, encapsulation efficiency, PDI, and release rate and shows a high anticancer effect on cell lines. The melittin-loaded niosome affects the genes expression by studied cells were higher than other samples; down-regulates the expression of Bcl2, MMP2, and MMP9 genes while they up-regulate the expression of Bax, Caspase3 and Caspase9 genes. They have also enhanced the apoptosis rate and inhibited cell migration, invasion in both cell lines compared to the melittin samples. Results of histopathology showed reduce mitosis index, invasion and pleomorphism in melittin-loaded niosome. Renal and hepatic biomarker activity did not significantly differ in melittin-loaded niosome and melittin compared to healthy control. In immunohistochemistry, P53 expression did not show a significant change in all groups. Conclusions Our study successfully declares that melittin-loaded niosome had more anti-cancer effects than free melittin. This project has demonstrated that niosomes are suitable vesicle carriers for melittin, compare to the free form.


2021 ◽  
Author(s):  
Damian Ignacio Delbart ◽  
German Francisco Giri ◽  
Agostina Cammarata ◽  
Lizeth Ariza Bareño ◽  
Natalia Loreley Amigo ◽  
...  

Abstract Purpose: Breast cancer is the leading cause of cancer death among women worldwide. For this reason, the development of new therapies is still essential. In this work we have analyzed the antitumor potential of levoglucosenone, a chiral building block derived from glucose, and three structurally related analogues obtained from soybean hulls pyrolysis.Methods: Employing human and murine mammary cancer models, we have evaluated the effect of our compounds on cell viability through MTS assay, apoptosis induction by acridine orange / ethidium bromide staining and/or flow cytometry and the loss of mitochondrial potential by tetramethylrhodamine methyl ester staining. Autophagy and senescence induction were also evaluated by Western blot and β-galactosidase activity respectively. Secreted metalloproteases activity was determined by quantitative zymography. Migratory capacity was assessed by wound healing assays while invasive potential was analyzed using Matrigel-coated transwell chambers. In vivo studies were also performed to evaluate subcutaneous tumor growth and experimental lung colonization.Results: Apoptosis was identified as the main mechanism responsible for the reduction of monolayer cell content induced by the compounds without detecting modulations of autophagy or senescence processes. Two of the four compounds were able to modulate in vitro events associated with tumor progression, such as migratory potential, invasiveness, and proteases secretion. Furthermore, tumor volume and metastatic spread were significantly reduced in vivo after treatment with the compounds.Conclusion: We could obtain from soybean hulls, a material with almost no commercial value, a variety of chemical compounds useful for breast cancer treatment.


2012 ◽  
Vol 14 (4) ◽  
pp. 330-336 ◽  
Author(s):  
Camila Salata ◽  
Samara Cristina Ferreira-Machado ◽  
André Luiz Mencalha ◽  
Cherley Borba Vieira de Andrade ◽  
Vera Maria Araújo de Campos ◽  
...  

2019 ◽  
Vol 54 ◽  
pp. 101370 ◽  
Author(s):  
Irma Danielle Rodrigues Pedro ◽  
Osmar Patricio Almeida ◽  
Helen Rodrigues Martins ◽  
Janaína de Alcântara Lemos ◽  
André Luís Branco de Barros ◽  
...  

Oncogene ◽  
2021 ◽  
Author(s):  
Yujing Zhang ◽  
Gang Shi ◽  
Hantao Zhang ◽  
Qi Xiong ◽  
Fuyi Cheng ◽  
...  

AbstractDexamethasone (Dex), as a pretreatment agent, is widely used to attenuate the side effects of chemotherapy in breast cancer treatment. However, whether and how Dex affects breast cancer metastasis remain to be furtherly understood. In this study, we established several mouse breast cancer metastatic models to study the effect of Dex in vitro and in vivo. Transwell, Western Blot and RNA interference were applied to study the molecular mechanism of Dex in promoting breast cancer cell migration. Meanwhile, the effect of Dex on lung metastasis of breast cancer in Dex combined with PTX chemotherapy was discussed. Our results confirmed that Dex could promote breast cancer cell metastasis both in vitro and in vivo. Mechanistic studies revealed that this pro-metastatic effect of Dex was mediated by the GR-PI3K-SGK1-CTGF pathway in tumor cells. Ligation of Dex and glucocorticoid receptor (GR) on tumor cells activated the PI3K signaling pathway and upregulated serum glucocorticoid-inducible kinase 1 (SGK1) expression, and then increased the expression of connective tissue growth factor (CTGF) through Nedd4l-Smad2. Moreover, Dex was the leading factor for lung metastasis in a standard regimen for breast cancer treatment with paclitaxel and Dex. Importantly, targeting SGK1 with the inhibitor GSK650394 remarkably reduced lung metastasis in this regimen. Our present data provide new insights into Dex-induced breast cancer metastasis and indicate that SGK1 could be a candidate target for the treatment of breast cancer metastasis.


2011 ◽  
Vol 99 ◽  
pp. S12-S13 ◽  
Author(s):  
F. Cavagnetto ◽  
S. Agostinelli ◽  
G. Taccini ◽  
A. Soriani ◽  
L. Strigari ◽  
...  

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