scholarly journals Long non-coding RNA MIR200CHG promotes breast cancer proliferation, invasion, and drug resistance by interacting with and stabilizing YB-1

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Li Tang ◽  
Da Wei ◽  
Xinyu Xu ◽  
Xuelian Mao ◽  
Dongping Mo ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Drug Resistance ◽  
Molecular Mechanisms ◽  
Cancer Proliferation ◽  
In Vivo Experiments ◽  
Expression Of Genes ◽  
Non Coding Rna ◽  
Cancer Tissues

AbstractLong non-coding RNAs (lncRNA) have been identified as key regulators of tumorigenesis and development. We aim to explore the biological functions and molecular mechanisms of lncRNA MIR200CHG in breast cancer. We found that MIR200CHG is highly expressed in breast cancer tissues and is related to the tumor size and histopathological grade. In vitro and in vivo experiments confirmed that MIR200CHG can promote breast cancer proliferation, invasion, and drug resistance. MIR200CHG directly binds to the transcription factor Y-box binding protein-1 (YB-1), and inhibits its ubiquitination and degradation. MIR200CHG regulates YB-1 phosphorylation at serine 102, thereby affecting the expression of genes related to tumor cell proliferation, apoptosis, invasion, and drug resistance. Additionally, MIR200CHG partially affects the expression of miR-200c/141-3p encoded by its intron region. Therefore, MIR200CHG can promote the proliferation, invasion, and drug resistance of breast cancer by interacting with and stabilizing YB-1, and has the potential to become a target for breast cancer treatment.

scholarly journals CLDN6 Suppresses c–MYC–Mediated Aerobic Glycolysis to Inhibit Proliferation by TAZ in Breast Cancer

2021 ◽  
Vol 23 (1) ◽  
pp. 129
Author(s):  
Huinan Qu ◽  
Da Qi ◽  
Xinqi Wang ◽  
Yuan Dong ◽  
Qiu Jin ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Molecular Mechanisms ◽  
Aerobic Glycolysis ◽  
Lactate Production ◽  
Suppressor Gene ◽  
Binding Motif ◽  
Cancer Proliferation ◽  
In Vivo Experiments

Claudin 6 (CLDN6) was found to be a breast cancer suppressor gene, which is lowly expressed in breast cancer and inhibits breast cancer cell proliferation upon overexpression. However, the mechanism by which CLDN6 inhibits breast cancer proliferation is unclear. Here, we investigated this issue and elucidated the molecular mechanisms by which CLDN6 inhibits breast cancer proliferation. First, we verified that CLDN6 was lowly expressed in breast cancer tissues and that patients with lower CLDN6 expression had a worse prognosis. Next, we confirmed that CLDN6 inhibited breast cancer proliferation through in vitro and in vivo experiments. As for the mechanism, we found that CLDN6 inhibited c–MYC–mediated aerobic glycolysis based on a metabolomic analysis of CLDN6 affecting cellular lactate levels. CLDN6 interacted with a transcriptional co–activator with PDZ-binding motif (TAZ) and reduced the level of TAZ, thereby suppressing c–MYC transcription, which led to a reduction in glucose uptake and lactate production. Considered together, our results suggested that CLDN6 suppressed c–MYC–mediated aerobic glycolysis to inhibit the proliferation of breast cancer by TAZ, which indicated that CLDN6 acted as a novel regulator of aerobic glycolysis and provided a theoretical basis for CLDN6 as a biomarker of progression in breast cancer.

PEAK1 promotes invasion and metastasis and confers drug resistance in breast cancer

2021 ◽  
Author(s):  
xingang wang ◽  
YAN ZHENG ◽  
YU WANG
Keyword(s):  
Breast Cancer ◽  
Drug Resistance ◽  
Cell Growth ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Multi Drug Resistance ◽  
Cancer Tissues

Abstract Background and AimsPseudopodium-enriched atypical kinase 1 (PEAK1) has reported to be upregulated in human malignancies and related with poor prognosis. Enhanced PEAK1 expression facilitates tumor cell survival, invasion, metastasis and chemoresistance. However, the role of PEAK1 in breast cancer is not clear. Here, we investigated the PEAK1 expression in breast cancer and analyzed its relation with clinicopathological status and chemotherapy resistance to the neoadjuvant chemotherapy (NAC). We also investigated the role of PEAK1 on breast cancer cells in vitro and in vivo. MethodsImmunohistochemistry (IHC) was performed in 112 surgical resected breast cancer tissues. The associations between clinicopathological status, multi-drug resistance and PEAK1 expression were determined. Effect of PEAK1 overexpression or down-expression on proliferation, colony formation, invasion, migration, metastasis and Doxorubicin sensitivity in the MCF-7 cells in vitro and in vivo was detected. ResultsPEAK1 was overexpressed in breast cancer tissues and NAC -resistant breast cancer tissues. High PEAK1 expression was related with tumor size, high tumor grade, T stage, LN metastasis, recurrence, Ki-67 expression, Her-2 expression and multi-drug resistance. Targeting PEAK1 inhibited cell growth, invasion, metastasis and reversed chemoresistance to Doxorubicin in breast cancer cells in vitro and in vivo. ConclusionHigh PEAK1 expression was associated with invasion, metastasis and chemoresistance of breast cancers. Furthermore, targeting PEAK1 could inhibit cell growth and metastasis, and reverse chemoresistance in breast cancer cells, which provides an effective treatment strategies for breast cancer.

scholarly journals NcRNAs-mediated High Expression of TIMM8A Correlates with Poor Prognosis and Act as an Oncogene in Breast Cancer

2021 ◽  
Author(s):  
Zhonglin Wang ◽  
Shuqin Li ◽  
Feng Xu ◽  
Jingyue Fu ◽  
Jie Sun ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Poor Prognosis ◽  
Molecular Mechanisms ◽  
Human Cancer ◽  
Luciferase Reporter ◽  
Inner Mitochondrial Membrane ◽  
Cancer Proliferation ◽  
Bioinformatics Analyses

Abstract Background: Breast cancer is notorious for its increasing incidence for decades. Ascending evidence has demonstrated that translocase of inner mitochondrial membrane (TIMM) proteins play vital roles in progression of several types of human cancer. However, the biological behaviors and molecular mechanisms of TIMM8A in breast cancer remain not fully illustrated.Methods: Pan-cancer analysis was firstly performed for TIMM8A’s expression and prognosis by Oncomine database. Subsequently, TIMM8A-related noncoding RNAs (ncRNAs) were identified by a series of bioinformatics analyses and dual-luciferase reporter assay, including expression analysis, correlation analysis, and survival analysis. Moreover, the effect of TIMM8A on breast cancer proliferation and apoptosis was evaluated in vitro by CCK-8 assays, colony formation assays and Western blot assays and the in vivo effect was revealed through a patient-derived xenograft mouse model.Results: We found that TIMM8A showed higher expression level in breast cancer and the higher TIMM8A mRNA expression group had a poorer prognosis than the lower TIMM8A group. hsa-circ-0107314/hsa-circ-0021867/hsa-circ-0122013 might be the three most potential upstream circRNAs of hsa-miR-34c-5p/hsa-miR-449a-TIMM8A axis in breast cancer. TIMM8A promotes proliferation of breast cancer cells in vitro and tumor growth in vivo.Conclusion: Our results confirmed that ncRNAs-mediated upregulation of TIMM8A correlated with poor prognosis and act as an oncogene in breast cancer.

scholarly journals Exosomes from tamoxifen-resistant breast cancer cells transmit drug resistance partly by delivering miR-9-5p

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jianhui Liu ◽  
Shaoliang Zhu ◽  
Wei Tang ◽  
Qinghua Huang ◽  
Yan Mei ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Drug Resistance ◽  
Cell Line ◽  
Bioinformatic Analysis ◽  
In Vivo Experiments ◽  
Luciferase Activity Assay ◽  
Tamoxifen Resistant ◽  
Mcf 7

Abstract Background Resistance to drug therapy is a major impediment for successful treatment of patients suffering from breast cancer (BC). Tamoxifen (TAM) is an extensively used therapeutic agent, which substantially reduces the risk of recurrence and associated mortality in BC. This study demonstrated that exosomal transfer of microRNA-9-5p (miR-9-5p) enhanced the resistance of MCF-7 cells to TAM. Methods Initially, BC-related differentially expressed genes (DEGs) and their upstream regulatory miRNAs were identified. The TAM-resistant MCF-7 (MCF-7/TAM) cell line and the non-medicated sensitive MCF-7 cell line were formulated, followed by isolation of the exosomes. Next, the apoptosis rate of exosome-treated MCF-7 cells was determined after co-culture with TAM. The interaction between miR-9-5p and ADIPOQ was identified by a combination of bioinformatic analysis and luciferase activity assay. In order to validate the effect of miR-9-5p and ADIPOQ on TAM resistance in the MCF-7 cells in vitro and in vivo, miR-9-5p was delivered into the exosomes. ADIPOQ and miR-9-5p were identified as the BC-related DEG and upstream regulatory miRNA. Results Exosomes derived from the MCF-7/TAM cells could increase the resistance of MCF-7 cells to TAM. Notably, miR-9-5p altered the sensitivity of BC cells to TAM. In addition, ADIPOQ was negatively regulated by miR-9-5p. Furthermore, MCF-7/TAM cell-derived miR-9-5p inhibited the apoptosis of MCF-7 cells, and promoted the cell resistance to TAM. In vivo experiments in nude mice ascertained that the tumor injected with exosomal miR-9-5p showed improved resistance to TAM. Conclusions Exosomal transfer of miR-9-5p augmented the drug resistance of BC cells to TAM by down-regulating ADIPOQ, suggesting its functionality as a candidate molecular target for the management of BC.

scholarly journals Let-7d Inhibits Growth and Metastasis in Breast Cancer by Targeting Jab1/Cops5

2018 ◽  
Vol 47 (5) ◽  
pp. 2126-2135 ◽  
Author(s):  
Yongchang Wei ◽  
Guohong Liu ◽  
Balu Wu ◽  
Yufen Yuan ◽  
Yunbao Pan
Keyword(s):  
Breast Cancer ◽  
Cancer Patients ◽  
Tumor Development ◽  
Luciferase Reporter ◽  
Breast Cancer Cell Lines ◽  
Breast Cancer Patients ◽  
In Vivo Experiments ◽  
Cancer Tissues

Background/Aims: MicroRNAs (miRNAs) regulate the expressions of cancer-related genes, and are involved in the development and progression of various human cancers. Here, we performed further analyses to determine whether let-7d is functionally linked to Jab1 in breast cancer. Methods: In situ hybridization and immunohistochemical analyses were used to determine the level of let-7d and Jab1 in breast cancer clinical specimens and its correlation with clinicopathological data. Let-7d overexpressing breast cancer cell lines combined with mouse models bearing cell-derived xenografts were used to assess the functional role of let-7d both in vitro and in vivo. Results: In this study, we found that let-7d was downregulated in breast cancer tissues, coupled with the elevations of Jab1 protein expressions, compared with paired adjacent noncancerous breast tissues. Let-7d overexpression significantly suppressed the proliferation and invasion in MCF-7 and MDA-MB-231 cells. Dual luciferase reporter assay indicated that Jab1 was the direct target of let-7d. Stepwise studies from in vitro and in vivo experiments indicated that let-7d overexpression inhibited cell growth and decreased Jab1 expressions in breast cancer cells and nude mice tumor tissues. Statistical analyses demonstrated that breast cancer patients with low levels of let-7d or high levels of Jab1 had a significant correlation with worse prognosis. Conclusion: These findings provide novel insights into molecular mechanism of let-7d and Jab1 in tumor development and progression of breast cancer, and thus let-7d/Jab1 are novel potential therapeutic targets for breast cancer patients.

scholarly journals The circACTN4 interacts with FUBP1 to promote tumorigenesis and progression of breast cancer by regulating the expression of proto-oncogene MYC

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Xiaosong Wang ◽  
Lei Xing ◽  
Rui Yang ◽  
Hang Chen ◽  
Min Wang ◽  
...  
Keyword(s):  
Breast Cancer ◽  
In Situ Hybridization ◽  
Molecular Mechanisms ◽  
Prognostic Significance ◽  
Luciferase Reporter ◽  
Invasion And Metastasis ◽  
Cancer Tissues

Abstract Background Recent studies have revealed that circular RNAs (circRNAs) play significant roles in the occurrence and development of many kinds of cancers including breast cancer (BC). However, the potential functions of most circRNAs and the molecular mechanisms underlying progression of BC remain elusive. Method Here, Circular RNA microarray was executed in 4 pairs of breast cancer tissues and para-cancer tissues. The expression and prognostic significance of circACTN4 in BC cells and tissues were determined by qRT-PCR and in situ hybridization. Gain-and loss-of-function experiments were implemented to observe the impacts of circACTN4 on the growth, invasion, and metastasis of BC cells in vitro and in vivo. Mechanistically, chromatin immunoprecipitation, luciferase reporter, RNA pulldown, mass spectrum, RNA immunoprecipitation, fluorescence in situ hybridization and co-immunoprecipitation assays were executed. Results CircACTN4 was significantly upregulated in breast cancer tissues and cells, its expression was correlated with clinical stage and poor prognosis of patients with BC. Ectopic expression of circACTN4 strikingly facilitated the growth, invasion, and metastasis of breast cancer cells in vitro and in vivo. Whereas knockdown of circACTN4 revealed opposite roles. CircACTN4 was mainly distributed in the nucleus. Further mechanistic research proved that circACTN4 could competitively bind to far upstream element binding protein 1 (FUBP1) to prevent the combination between FUBP1 and FIR, thereby activating MYC transcription and facilitating tumor progression of breast cancer. Furthermore, we found that upstream transcription factor 2 (USF2) might promote the biogenesis of circACTN4. Conclusion Our findings uncover a pivotal mechanism that circACTN4 mediated by USF2 might interact with FUBP1 to promote the occurrence and development of breast cancer via enhancing the expression of MYC. CircACTN4 could be a novel potential target for diagnosis and treatment of breast cancer.

Targeting PKM2 promotes chemosensitivity of breast cancer cells in vitro and in vivo

2021 ◽  
pp. 1-10
Author(s):  
Yu Wang ◽  
Han Zhao ◽  
Ping Zhao ◽  
Xingang Wang
Keyword(s):  
Breast Cancer ◽  
Neoadjuvant Chemotherapy ◽  
Cancer Cells ◽  
Cancer Patients ◽  
Poor Prognosis ◽  
Breast Cancer Cells ◽  
Breast Cancer Patients ◽  
Cancer Tissues

BACKGROUND: Pyruvate kinase M2 (PKM2) was overexpressed in many cancers, and high PKM2 expression was related with poor prognosis and chemoresistance. OBJECTIVE: We investigated the expression of PKM2 in breast cancer and analyzed the relation of PKM2 expression with chemotherapy resistance to the neoadjuvant chemotherapy (NAC). We also investigated whether PKM2 could reverse chemoresistance in breast cancer cells in vitro and in vivo. METHODS: Immunohistochemistry (IHC) was performed in 130 surgical resected breast cancer tissues. 78 core needle biopsies were collected from breast cancer patients before neoadjuvant chemotherapy. The relation of PKM2 expression and multi-drug resistance to NAC was compared. The effect of PKM2 silencing or overexpression on Doxorubicin (DOX) sensitivity in the MCF-7 cells in vitro and in vivo was compared. RESULTS: PKM2 was intensively expressed in breast cancer tissues compared to adjacent normal tissues. In addition, high expression of PKM2 was associated with poor prognosis in breast cancer patients. The NAC patients with high PKM2 expression had short survival. PKM2 was an independent prognostic predictor for surgical resected breast cancer and NAC patients. High PKM2 expression was correlated with neoadjuvant treatment resistance. High PKM2 expression significantly distinguished chemoresistant patients from chemosensitive patients. In vitro and in vivo knockdown of PKM2 expression decreases the resistance to DOX in breast cancer cells in vitro and tumors in vivo. CONCLUSION: PKM2 expression was associated with chemoresistance of breast cancers, and could be used to predict the chemosensitivity. Furthermore, targeting PKM2 could reverse chemoresistance, which provides an effective treatment methods for patients with breast cancer.

Radiation activates the NORAD expression to promote ESCC radioimmunotherapy resistance via EEPD1/ATR/Chk1 signaling by inhibiting the pri-miR-199 processing and exosomal transfer of miR-199a-5p

2021 ◽  
Author(s):  
Yuchen Sun ◽  
Jizhao Wang ◽  
Xuanzi Sun ◽  
Jing Li ◽  
Xu Zhao ◽  
...  
Keyword(s):  
Its Region ◽  
Luciferase Reporter ◽  
In Vivo Experiments ◽  
Cycle Arrest ◽  
Non Coding Rna ◽  
Irradiation Treatment ◽  
Recombination Repair ◽  
Reporter Assays

Abstract Background Radioresistance, a poorly understood phenomenon, results in the failure of radiotherapy and consequent local recurrence, threatening a large proportion of ESCC patients. To date, lncRNAs have been found to be involved in diverse biological processes, including radioresistance.Methods ELISA was used to evaluated the H3 modifications in radio-resistant ESCC cells. FISH and qRT-PCR were adopted to examine the expression and localization of lncRNA-NORAD, pri-miR-199a and miR-199a. Electron microscopy and Nanoparticle tracking analysis (NTA) was conducted to observe and identify exosomes. High-throughput RNA sequencing and TMT mass spectrometry were performed to identify the functional lncRNAs and proteins involved in ESCC radioresistance. A series of in vitro and in vivo experiments were performed to investigate the biological effect of NORAD. CHIP, qPCR-RIP, co-IP and dual-luciferase reporter assays were used to explore the interaction of related RNAs and proteins. Results We show here that a DNA damage activated non-coding RNA-NORAD, which is critical for ESCC radio-resistance. NORAD was highly expressed in radio-resistant ESCC cells and tissues. Irradiation treatment promotes NORAD expression via enhancing H3K4me2 enrichment on its region. NORAD knockdown cells exhibit significantly hypersensitivity to irradiation in vivo and in vitro. NORAD is required for initiating repair and restart of stalled forks, G2 cycle arrest and homologous recombination repair upon irradiation treatment. Mechanistically, NORAD inhibits miR-199a expression by competitively binding PUM1 from pri-miR-199a, inhibiting the process of pri-miR-199a. Mature miR-199a in NORAD-knockdown cells can be packaged into exosomes; miR-199a restores the radiosensitivity of radioresistant cells by targeting EEPD1, then inhibiting ATR/Chk1 signaling pathway. Simultaneously, NORAD knockdown blocks the ubiquitination of PD-L1, leads to the better response for radiation and anti-PD-1 treatment in mouse model.Conclusion This study raises the possibility that LncRNA-NORAD could be a potential treatment target for improving the efficiency of immunotherapy in combination with radiation in ESCC.

scholarly journals CBP/β-Catenin/FOXM1 Is a Novel Therapeutic Target in Triple Negative Breast Cancer

Cancers ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 525 ◽  
Author(s):  
Alexander Ring ◽  
Cu Nguyen ◽  
Goar Smbatyan ◽  
Debu Tripathy ◽  
Min Yu ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Gene Expression ◽  
Drug Resistance ◽  
Triple Negative Breast Cancer ◽  
Therapeutic Target ◽  
Triple Negative ◽  
Creb Binding Protein ◽  
Novel Therapeutic

Background: Triple negative breast cancers (TNBCs) are an aggressive BC subtype, characterized by high rates of drug resistance and a high proportion of cancer stem cells (CSC). CSCs are thought to be responsible for tumor initiation and drug resistance. cAMP-response element-binding (CREB) binding protein (CREBBP or CBP) has been implicated in CSC biology and may provide a novel therapeutic target in TNBC. Methods: RNA Seq pre- and post treatment with the CBP-binding small molecule ICG-001 was used to characterize CBP-driven gene expression in TNBC cells. In vitro and in vivo TNBC models were used to determine the therapeutic effect of CBP inhibition via ICG-001. Tissue microarrays (TMAs) were used to investigate the potential of CBP and associated proteins as biomarkers in TNBC. Results: The CBP/ß-catenin/FOXM1 transcriptional complex drives gene expression in TNBC and is associated with increased CSC numbers, drug resistance and poor survival outcome. Targeting of CBP/β-catenin/FOXM1 with ICG-001 eliminated CSCs and sensitized TNBC tumors to chemotherapy. Immunohistochemistry of TMAs demonstrated a significant correlation between FOXM1 expression and TNBC subtype. Conclusion: CBP/β-catenin/FOXM1 transcriptional activity plays an important role in TNBC drug resistance and CSC phenotype. CBP/β-catenin/FOXM1 provides a molecular target for precision therapy in triple negative breast cancer and could form a rationale for potential clinical trials.

scholarly journals Nanostructured Dihydroartemisinin Plus Epirubicin Liposomes Enhance Treatment Efficacy of Breast Cancer by Inducing Autophagy and Apoptosis

Nanomaterials ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 804 ◽  
Author(s):  
Ying-Jie Hu ◽  
Jing-Ying Zhang ◽  
Qian Luo ◽  
Jia-Rui Xu ◽  
Yan Yan ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Therapeutic Strategy ◽  
Beclin 1 ◽  
Type I ◽  
Programmed Death ◽  
Cancer Tissues

The heterogeneity of breast cancer and the development of drug resistance are the relapse reasons of disease after chemotherapy. To address this issue, a combined therapeutic strategy was developed by building the nanostructured dihydroartemisinin plus epirubicin liposomes. Investigations were performed on human breast cancer cells in vitro and xenografts in nude mice. The results indicated that dihydroartemisinin could significantly enhance the efficacy of epirubicin in killing different breast cancer cells in vitro and in vivo. We found that the combined use of dihydroartemisinin with epirubicin could efficiently inhibit the activity of Bcl-2, facilitate release of Beclin 1, and further activate Bax. Besides, Bax activated apoptosis which led to the type I programmed death of breast cancer cells while Beclin 1 initiated the excessive autophagy that resulted in the type II programmed death of breast cancer cells. In addition, the nanostructured dihydroartemisinin plus epirubicin liposomes prolonged circulation of drugs, and were beneficial for simultaneously delivering drugs into breast cancer tissues. Hence, the nanostructured dihydroartemisinin plus epirubicin liposomes could provide a new therapeutic strategy for treatment of breast cancer.

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