FGFR4 phosphorylates MST1 to confer breast cancer cells resistance to MST1/2-dependent apoptosis

AbstractCancer cells balance with the equilibrium of cell death and growth to expand and metastasize. The activity of mammalian sterile20-like kinases MST1/2 has been linked to apoptosis and tumor suppression via YAP/Hippo pathway dependent and independent mechanisms. With a kinase substrate screen we identified here MST1 and MST2 among the top substrates for fibroblast growth factor receptor 4 (FGFR4). In COS-1 cells, MST1 was phosphorylated at Y433 residue in an FGFR4 kinase activity-dependent manner, as assessed by mass spectrometry. Blockade of this phosphorylation by Y433F mutation induced MST1 activation, as reflected by increased autophosphorylation at T183 in FGFR4 overexpressing MDA-MB-231 cells. Importantly, the specific short-term inhibition or knockdown of FGFR4 also led to MST1/2 activation in conjunction with induction of MST1/2-dependent apoptosis in an endogenous model of HER2+ breast cancer cells. Moreover, FGFR4 knockdown increased the level of active nuclear MST1 coincidentally with cell polarization and membrane-association of YAP in three-dimensional breast cancer cell spheres. Consistently, FGFR4 overexpression correlated with reduced Hippo pathway-mediated, nuclear translocation-inhibiting YAP phosphorylation, and abysmal HER2+ breast carcinoma patient outcome in TCGA cohort. Our results reveal a novel mechanism for FGFR4 oncogenic activity via suppression of the stress-associated MST1/2-dependent apoptosis machinery in the tumor cells with prominent HER/ERBB signaling driven proliferation.

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SAT-124 Optimization of Experimental Conditions for Mimicking Hypoxia in Cultured Breast Cancer Cells by Using Cobalt(II) Chloride (CoCl2)

Journal of the Endocrine Society ◽

10.1210/jendso/bvaa046.1318 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

Author(s):

Karin Chen ◽

Leo Satlof ◽

Udithi Kothapalli ◽

Noah Ziluck ◽

Maribel Lema ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Cell Apoptosis ◽

Breast Cancer Cells ◽

Nuclear Translocation ◽

Breast Cancer Cell Lines ◽

Mrna Levels ◽

Dependent Manner ◽

Experimental Conditions

Abstract Hypoxia is a common phenomenon in solid tumor development caused by a decrease in either oxygen concentration or oxygen pressure as a result of rapid tumor cell growth. Hypoxia is characterized by stabilization of the alpha subunit of the hypoxia-inducible factor (HIF-1α) and its nuclear translocation and heterodimerization with HIF-1β. Activation of this signaling pathway involves multiple downstream effectors including carbonic anhydrase 9 (CA9, s. CAIX). A reliable method to mimic hypoxia utilizes cobalt(II) chloride (CoCl2), which directly induces the expression of HIF-1α. The aim of this study was to optimize the experimental conditions for CoCl2 treatment of breast cancer cells in vitro using three human breast cancer cell lines (MDA-MB-231, T-47D, and MCF-7 cells). We performed time- and concentration-response experiments, using various concentrations of CoCl2 (50, 100, 200, and 300 μM) for 24 and 48 hours, and measured the expression of HIF-1α and CA9 by qRT-PCR and Western blot analyses. Results demonstrated that CoCl2 downregulated HIF-1α mRNA levels but upregulated CA9 mRNA levels in a concentration- and time-dependent manner. Concomitantly, CoCl2 treatment resulted in a significant induction of HIF-1α protein levels. We further investigated the effect of the CoCl2 concentrations listed above on cell apoptosis using an in situ apoptosis detection kit. The results demonstrated that concentrations of CoCl2 up to 100 μM had no significant effect on cell apoptosis.

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Arctigenin Enhances the Cytotoxic Effect of Doxorubicin in MDA-MB-231 Breast Cancer Cells

International Journal of Molecular Sciences ◽

10.3390/ijms21082997 ◽

2020 ◽

Vol 21 (8) ◽

pp. 2997 ◽

Cited By ~ 2

Author(s):

Kyu-Shik Lee ◽

Min-Gu Lee ◽

Yun-Suk Kwon ◽

Kyung-Soo Nam

Keyword(s):

Breast Cancer ◽

Cell Death ◽

Cancer Cells ◽

Human Breast Cancer ◽

Breast Cancer Cells ◽

Nuclear Translocation ◽

Dependent Manner ◽

Human Breast Cancer Cells ◽

Human Breast ◽

Concentration Dependent Manner

Several reports have described the anti-cancer activity of arctigenin, a lignan extracted from Arctium lappa L. Here, we investigated the effect of arctigenin (ATG) on doxorubicin (DOX)-induced cell death using MDA-MB-231 human breast cancer cells. The results showed that DOX-induced cell death was enhanced by ATG/DOX co-treatment in a concentration-dependent manner and that this was associated with increased DOX uptake and the suppression of multidrug resistance-associated protein 1 (MRP1) gene expression in MDA-MB-231 cells. ATG enhanced DOX-induced DNA damage and decreased the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and the expressions of RAD51 and survivin. Cell death caused by ATG/DOX co-treatment was mediated by the nuclear translocation of apoptosis inducing factor (AIF), reductions in cellular and mitochondrial Bcl-2 and Bcl-xL, and increases in mitochondrial BAX levels. However, caspase-3 and -7 did not participate in DOX/ATG-induced cell death. We also found that DOX/ATG-induced cell death was linked with activation of the p38 signaling pathway and suppressions of the phosphorylations and expressions of Akt and c-Jun N-terminal kinase. Taken together, these results show that ATG enhances the cytotoxic activity of DOX in MDA-MB-231 human breast cancer cells by inducing prolonged p21 expression and p38-mediated AIF-dependent cell death. In conclusion, our findings suggest that ATG might alleviate the side effects and improve the therapeutic efficacy of DOX.

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Primaquine Inhibits the Endosomal Trafficking and Nuclear Localization of EGFR and Induces the Apoptosis of Breast Cancer Cells by Nuclear EGFR/Stat3-Mediated c-Myc Downregulation

International Journal of Molecular Sciences ◽

10.3390/ijms222312961 ◽

2021 ◽

Vol 22 (23) ◽

pp. 12961

Author(s):

Ji-Hyang Kim ◽

Hack-Sun Choi ◽

Dong-Sun Lee

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Nuclear Translocation ◽

Growth Factor Receptor ◽

Endosomal Trafficking ◽

Protein Levels ◽

Early Endosomes

Triple-negative breast cancer (TNBC) cells overexpress the epidermal growth factor receptor (EGFR). Nuclear EGFR (nEGFR) drives resistance to anti-EGFR therapy and is correlated with poor survival in breast cancer. Inhibition of EGFR nuclear translocation may be a reasonable approach for the treatment of TNBC. The anti-malarial drugs chloroquine and primaquine have been shown to promote an anticancer effect. The aim of the present study was to investigate the effect and mechanism of chloroquine- and primaquine-induced apoptosis of breast cancer cells. We showed that primaquine, a malaria drug, inhibits the growth, migration, and colony formation of breast cancer cells in vitro, and inhibits tumor growth in vivo. Primaquine induces damage to early endosomes and inhibits the nuclear translocation of EGFR. Primaquine inhibits the interaction of Stat3 and nEGFR and reduces the transcript and protein levels of c-Myc. Moreover, primaquine and chloroquine induce the apoptosis of breast cancer cells through c-Myc/Bcl-2 downregulation, induce early endosome damage and reduce nEGFR levels, and induce apoptosis in breast cancer through nEGFR/Stat3-dependent c-Myc downregulation. Our study of primaquine and chloroquine provides a rationale for targeting EGFR signaling components in the treatment of breast cancer.

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Glucose-sensitive acetylation of Seryl tRNA synthetase regulates lipid synthesis in breast cancer

Signal Transduction and Targeted Therapy ◽

10.1038/s41392-021-00714-0 ◽

2021 ◽

Vol 6 (1) ◽

Author(s):

Jin Zhao ◽

Hangming Bai ◽

Xiaoyu Li ◽

Jie Yan ◽

Gengyi Zou ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Nuclear Translocation ◽

De Novo ◽

Lipid Synthesis ◽

Trna Synthetase ◽

Lipid Biosynthesis ◽

Normal Mammary Gland ◽

Dependent Manner

AbstractAbnormally enhanced de novo lipid biosynthesis has been increasingly realized to play crucial roles in the initiation and progression of varieties of cancers including breast cancer. However, the mechanisms underlying the dysregulation of lipid biosynthesis in breast cancer remain largely unknown. Here, we reported that seryl tRNA synthetase (SerRS), a key enzyme for protein biosynthesis, could translocate into the nucleus in a glucose-dependent manner to suppress key genes involved in the de novo lipid biosynthesis. In normal mammary gland epithelial cells glucose can promote the nuclear translocation of SerRS by increasing the acetylation of SerRS at lysine 323. In SerRS knock-in mice bearing acetylation-defective lysine to arginine mutation, we observed increased body weight and adipose tissue mass. In breast cancer cells the acetylation and nuclear translocation of SerRS are greatly inhibited. Overexpression of SerRS, in particularly the acetylation-mimetic lysine to glutamine mutant, dramatically inhibits the de novo lipid synthesis and hence greatly suppresses the proliferation of breast cancer cells and the growth of breast cancer xenografts in mice. We further identified that HDAC4 and HDAC5 regulated the acetylation and nuclear translocation of SerRS. Thus, we identified a SerRS-meditated inhibitory pathway in glucose-induced lipid biosynthesis, which is dysregulated in breast cancer.

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Faculty Opinions recommendation of Metastatic breast cancer cells colonize and degrade three-dimensional osteoblastic tissue in vitro.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1159048.619335 ◽

2009 ◽

Author(s):

Dietmar Werner Hutmacher ◽

Maria Woodruff

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Three Dimensional ◽

Metastatic Breast

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Arginine Methyltransferase PRMT1 Regulates p53 Activity in Breast Cancer

Life ◽

10.3390/life11080789 ◽

2021 ◽

Vol 11 (8) ◽

pp. 789

Author(s):

Li-Ming Liu ◽

Qiang Tang ◽

Xin Hu ◽

Jing-Jing Zhao ◽

Yuan Zhang ◽

...

Keyword(s):

Breast Cancer ◽

Cell Growth ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Asymmetric Dimethylarginine ◽

Human Cancer ◽

Specific Inhibitor ◽

Dependent Manner ◽

Breast Tumorigenesis ◽

Stress Signals

The protein p53 is one of the most important tumor suppressors, responding to a variety of stress signals. Mutations in p53 occur in about half of human cancer cases, and dysregulation of the p53 function by epigenetic modifiers and modifications is prevalent in a large proportion of the remainder. PRMT1 is the main enzyme responsible for the generation of asymmetric-dimethylarginine, whose upregulation or aberrant splicing has been observed in many types of malignancies. Here, we demonstrate that p53 function is regulated by PRMT1 in breast cancer cells. PRMT1 knockdown activated the p53 signal pathway and induced cell growth-arrest and senescence. PRMT1 could directly bind to p53 and inhibit the transcriptional activity of p53 in an enzymatically dependent manner, resulting in a decrease in the expression levels of several key downstream targets of the p53 pathway. We were able to detect p53 asymmetric-dimethylarginine signals in breast cancer cells and breast cancer tissues from patients, and the signals could be significantly weakened by silencing of PRMT1 with shRNA, or inhibiting PRMT1 activity with a specific inhibitor. Furthermore, PRMT1 inhibitors significantly impeded cell growth and promoted cellular senescence in breast cancer cells and primary tumor cells. These results indicate an important role of PRMT1 in the regulation of p53 function in breast tumorigenesis.

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