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

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.

2021 ◽  
pp. 1-10
Author(s):  
Yu Wang ◽  
Han Zhao ◽  
Ping Zhao ◽  
Xingang Wang

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.


Oncogene ◽  
2021 ◽  
Author(s):  
Francesco Pantano ◽  
Martine Croset ◽  
Keltouma Driouch ◽  
Natalia Bednarz-Knoll ◽  
Michele Iuliani ◽  
...  

AbstractBone metastasis remains a major cause of mortality and morbidity in breast cancer. Therefore, there is an urgent need to better select high-risk patients in order to adapt patient’s treatment and prevent bone recurrence. Here, we found that integrin alpha5 (ITGA5) was highly expressed in bone metastases, compared to lung, liver, or brain metastases. High ITGA5 expression in primary tumors correlated with the presence of disseminated tumor cells in bone marrow aspirates from early stage breast cancer patients (n = 268; p = 0.039). ITGA5 was also predictive of poor bone metastasis-free survival in two separate clinical data sets (n = 855, HR = 1.36, p = 0.018 and n = 427, HR = 1.62, p = 0.024). This prognostic value remained significant in multivariate analysis (p = 0.028). Experimentally, ITGA5 silencing impaired tumor cell adhesion to fibronectin, migration, and survival. ITGA5 silencing also reduced tumor cell colonization of the bone marrow and formation of osteolytic lesions in vivo. Conversely, ITGA5 overexpression promoted bone metastasis. Pharmacological inhibition of ITGA5 with humanized monoclonal antibody M200 (volociximab) recapitulated inhibitory effects of ITGA5 silencing on tumor cell functions in vitro and tumor cell colonization of the bone marrow in vivo. M200 also markedly reduced tumor outgrowth in experimental models of bone metastasis or tumorigenesis, and blunted cancer-associated bone destruction. ITGA5 was not only expressed by tumor cells but also osteoclasts. In this respect, M200 decreased human osteoclast-mediated bone resorption in vitro. Overall, this study identifies ITGA5 as a mediator of breast-to-bone metastasis and raises the possibility that volociximab/M200 could be repurposed for the treatment of ITGA5-positive breast cancer patients with bone metastases.


2020 ◽  
Author(s):  
Bo Fu ◽  
Wei Liu ◽  
Peng Li ◽  
Li Pan ◽  
Ke Li ◽  
...  

Abstract Background: Accumulating evidence indicates that circular RNAs (circRNAs) play critical roles in tumorigenesis and progression of various cancers. We previously identified a novel upregulated circRNA, circBCBM1 (hsa_circ_0001944), in the context of breast cancer brain metastasis. However, the potential biological function and molecular mechanism of circBCBM1 in breast cancer brain metastasis remain largely unknown.Methods: In this reserch, we validated the expression and characterization of circBCBM1 through RT-qPCR, Sanger sequencing, RNase R assay and fluorescence in situ hybridization (FISH). Functional experiments were performed to determine the effect of circBCBM1 on growth and metastasis of 231-BR cells both in vitro and in vivo. The regulatory mechanisms among circBCBM1, miR-125a (has-miR-125a-5p), and BRD4 (bromodomain containing 4) were investigated by RNA immunoprecipitation (RIP), RNA pull-down, luciferase reporter assay and western blot. Results: Our findings demonstrated that circBCBM1 is a stable and cytoplasmic circRNA. Functionally, silencing of circBCBM1 led to decreased proliferation and migration of 231-BR cells whereas elevated circBCBM1 expression showed reverse effects in vitro. These findings were confirmed in vivo in mouse models, as knockdown of circBCBM1 significantly decreased growth and brain metastases of 231-BR cells. Mechanistically, circBCBM1 functions as an endogenous miR-125a sponge to inhibit miR-125a activity, resulting in the upregulation of BRD4 expression and subsequent upregulation of MMP9 (matrix metallopeptidase 9) through Sonic hedgehog (SHH) signaling pathway. Importantly, circBCBM1 was markedly upregulated in the breast cancer brain metastasis cells and clinical tissue and plasma samples; besides, the overexpression of circBCBM1 in primary cancerous tissues was associated with shorter brain metastasis-free survival (BMFS) of breast cancer patients.Conclusions: These findings indicate that circBCBM1 is involved in breast cancer brain metastasis via circBCBM1/miR-125a/BRD4 axis, which sheds light on the pathogenic mechanism of circBCBM1 and provides translational evidence that circBCBM1 may serve as a novel diagnostic or prognostic biomarker and potential therapeutic target for breast cancer brain metastasis.


2020 ◽  
Vol 21 (8) ◽  
pp. 2974 ◽  
Author(s):  
Yasmin M. Attia ◽  
Samia A. Shouman ◽  
Salama A. Salama ◽  
Cristina Ivan ◽  
Abdelrahman M. Elsayed ◽  
...  

Cyclin-dependent kinase (CDK)-7 inhibitors are emerging as promising drugs for the treatment of different types of cancer that show chemotherapy resistance. Evaluation of the effects of CDK7 inhibitor, THZ1, alone and combined with tamoxifen is of paramount importance. Thus, in the current work, we assessed the effects of THZ1 and/or tamoxifen in two estrogen receptor-positive (ER+) breast cancer cell lines (MCF7) and its tamoxifen resistant counterpart (LCC2) in vitro and in xenograft mouse models of breast cancer. Furthermore, we evaluated the expression of CDK7 in clinical samples from breast cancer patients. Cell viability, apoptosis, and genes involved in cell cycle regulation and tamoxifen resistance were determined. Tumor volume and weight, proliferation marker (Ki67), angiogenic marker (CD31), and apoptotic markers were assayed. Bioinformatic data indicated CDK7 expression was associated with negative prognosis, enhanced pro-oncogenic pathways, and decreased response to tamoxifen. Treatment with THZ1 enhanced tamoxifen-induced cytotoxicity, while it inhibited genes involved in tumor progression in MCF-7 and LCC2 cells. In vivo, THZ1 boosted the effect of tamoxifen on tumor weight and tumor volume, reduced Ki67 and CD31 expression, and increased apoptotic cell death. Our findings identify CDK7 as a possible therapeutic target for breast cancer whether it is sensitive or resistant to tamoxifen therapy.


2021 ◽  
Author(s):  
Xiao Tong ◽  
Jiani Xing ◽  
Haizhou Liu ◽  
Shunheng Zhou ◽  
Yue Huang ◽  
...  

Abstract Background Long non-coding RNAs (lncRNAs) is widely described as a class of RNA longer than 200 nucleotides without encoding capability. But recent years, more and more open reading frames (ORFs) have been found in lncRNAs which indicate they have coding capacity. But the mechanisms of the encoding products in cancer are mostly unknown. We have previously shown lncRNA HCP5 is an oncogene in triple negative breast cancer (TNBC), and the aim of the current study was to investigate if lncRNA HCP5 encoding protein promotes TNBC by regulating ferroptosis. Methods We use bioinformatics to predict coding capacity. Molecular biology experiments and the xenograft assay in nude mice to study the mechanism of lncRNA HCP5 encoding protein. And the protein expression was evaluated in a tissue microarray of 140 invasive breast tumors and 45 pared precancerous breast tissues. Association between the protein expression and clinicopathologic features of breast cancer patients was analyzed. Results In this study, we identify that ORF in lncRNA HCP5 can encode a conserved protein with 132-amino acid. The protein, which is named HCP5-132aa, promotes TNBC growth. Mechanistically, the HCP5-132aa regulates GPX4 expression and lipid ROS level through ferroptosis pathway to promote TNBC progression. HCP5-132aa ORF knockdown synergizes with ferroptosis activators in vitro and in vivo. Breast cancer patients with high levels of HCP5-132aa have poorer prognosis. Conclusions Our study indicates that overexpression of lncRNA HCP5 encoding protein is a critical oncogenic event in TNBC. Our findings uncover a regulatory mechanism of ferroptosis in TNBC orchestrated by a protein encoded by an lncRNA.


2016 ◽  
Vol 130 (24) ◽  
pp. 2267-2276 ◽  
Author(s):  
Dong-xu He ◽  
Feng Gu ◽  
Jian Wu ◽  
Xiao-Ting Gu ◽  
Chun-Xiao Lu ◽  
...  

Chemotherapeutic response is critical for the successful treatment and good prognosis in cancer patients. In this study, we analysed the gene expression profiles of preoperative samples from oestrogen receptor (ER)-negative breast cancer patients with different responses to taxane-anthracycline-based (TA-based) chemotherapy, and identified a group of genes that was predictive. Pregnancy specific beta-1-glycoprotein 1 (PSG1) played a central role within signalling pathways of these genes. Inhibiting PSG1 can effectively reduce chemoresistance via a transforming growth factor-β (TGF-β)-related pathway in ER-negative breast cancer cells. Drug screening then identified dicumarol (DCM) to target the PSG1 and inhibit chemoresistance to TA-based chemotherapy in vitro, in vivo, and in clinical samples. Taken together, this study highlights PSG1 as an important mediator of chemoresistance, whose effect could be diminished by DCM.


Cancers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3821
Author(s):  
Hanna A. Zielinska ◽  
Carl S. Daly ◽  
Ahmad Alghamdi ◽  
Amit Bahl ◽  
Muhammed Sohail ◽  
...  

Insulin-like growth factor binding protein 3 (IGFBP-3) plays a key role in breast cancer progression and was recently shown to bind to the chaperone protein glucose-regulated protein 78 (GRP78); however, the clinical significance of this association remains poorly investigated. Here we report a direct correlation between the expression of GRP78 and IGFBP-3 in breast cancer cell lines and tumour sections. Kaplan–Meier survival plots revealed that patients with low GRP78 expression that are positive for IGFBP-3 had poorer survival rates than those with low IGFBP-3 levels, and we observed a similar trend in the publicly available METABRIC gene expression database. With breast cancer cells, in vitro IGFBP-3 enhanced induced apoptosis, however when GRP78 expression was silenced the actions of IGFBP-3 were switched from increasing to inhibiting ceramide (C2)-induced cell death and promoted cell invasion. Using immunofluorescence and cell surface biotinylation, we showed that knock-down of GRP78 negated the entry of IGFBP-3 into the cells. Together, our clinical and experimental results suggest that loss of GRP78 reduces IGFBP-3 entry into cells switching its actions to promote tumorigenesis and predicts a poor prognosis in breast cancer patients.


2021 ◽  
Author(s):  
Shiping Li ◽  
Xiaoyi Mi ◽  
Mingfang Sun ◽  
Jie Zhang ◽  
Miaomiao Hao ◽  
...  

Abstract Background: Recently, an increasing number of studies have focused on investigating long non-coding RNAs (lncRNAs) and their role in regulating the progression of various cancer types. However, the biological effects and underlying mechanisms of EGFR-AS1, a typical lncRNA, remain largely unclear in breast cancer.Methods: Differential expression of EGFR-AS1 in breast cancer tissue was analyzed using an integrative database and verified in breast cancer tissue samples and cells via real-time PCR analysis and western blotting analysis. The tumor promoter role of EGFR-AS1 in breast cancer cells was determined through MTT, EDU analysis, colony formation and transwell assays,and the effect of EGFR-AS1 on docetaxel drug sensitivity was examined. We then performed bioinformatic analysis and the dual-luciferase reporter assay to identify the binding sites of EGFR-AS1/miR-149-5p and miR-149-5p/ELP5. Results from western blotting and biological function studies provided insights into whether the EGFR-AS1/miR-149-5p/ELP5 axis regulates breast cancer development in vitro and in vivo. Results: EGFR-AS1 is upregulated in breast cancer tissues and cells and promotes the progression of breast cancer cells both in vitro and in vivo. Moreover, miR-149-5p is downregulated in breast cancer tissues and cell lines. Mechanistically, EGFR-AS1 regulates ELP5 levels by sponging miR-149-5p, thereby affecting cell progression and promoting epithelial-to-mesenchymal transition. Hence, the EGFR-AS1/miR-149-5p/ELP5 axis is involved in breast cancer proliferation, migration, invasion, and resistance to the chemotherapeutic drug, docetaxel, in breast cancer cells. Conclusions: EGFR-AS1 sponges miR-149-5p to affect the expression level of ELP5 ultimately acting as a new tumor promotor in breast cancer. This study provides novel insights into diagnostic and docetaxel-related chemotherapy targets for breast cancer.


2021 ◽  
Vol 2021 ◽  
pp. 1-18
Author(s):  
Jiahui Mao ◽  
Lingxia Wang ◽  
Junying Wu ◽  
Yichun Wang ◽  
Huiyan Wen ◽  
...  

miRNAs play a crucial part in multiple biological processes of cell proliferation, migration, apoptosis, and chemoresistance. In cancer, miRNAs can be divided into oncogenes or tumor suppressors on the basis of their functions in the carcinogenic process. The purpose of this study was to explore the roles and clinical diagnostic value of miR-370-3p in breast cancer. Our results demonstrated that miR-370-3p significantly promoted proliferation, metastasis, and stemness of breast cancer in vitro and in vivo. In particular, clinical data revealed that high expression of serum miR-370-3p and exosomal miR-370-3p from breast cancer patients was remarkably correlated with lymphatic metastasis and tumor node metastasis (TNM) stages. Mechanistically, miR-370-3p inhibited FBLN5 expression and activated the NF-κB signaling pathway to promote breast cancer cell proliferation, migration, and stemness. FBLN5 expression was significantly decreased in breast cancer cells and tumor tissues of breast cancer patients. Our research identified that miR-370-3p promoted breast cancer progression by inhibiting FBLN5 expression and activating the NF-κB signaling pathway. Serum exosomal miR-370-3p would provide a potential biomarker for the diagnosis of breast cancer.


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