Molecular Investigation on a Triple Negative Breast Cancer Xenograft Model Exposed to Proton Beams

Specific breast cancer (BC) subtypes are associated with bad prognoses due to the absence of successful treatment plans. The triple-negative breast cancer (TNBC) subtype, with estrogen (ER), progesterone (PR) and human epidermal growth factor-2 (HER2) negative receptor status, is a clinical challenge for oncologists, because of its aggressiveness and the absence of effective therapies. In addition, proton therapy (PT) represents an effective treatment against both inaccessible area located or conventional radiotherapy (RT)-resistant cancers, becoming a promising therapeutic choice for TNBC. Our study aimed to analyze the in vivo molecular response to PT and its efficacy in a MDA-MB-231 TNBC xenograft model. TNBC xenograft models were irradiated with 2, 6 and 9 Gy of PT. Gene expression profile (GEP) analyses and immunohistochemical assay (IHC) were performed to highlight specific pathways and key molecules involved in cell response to the radiation. GEP analysis revealed in depth the molecular response to PT, showing a considerable immune response, cell cycle and stem cell process regulation. Only the dose of 9 Gy shifted the balance toward pro-death signaling as a dose escalation which can be easily performed using proton beams, which permit targeting tumors while avoiding damage to the surrounding healthy tissue.

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Edelfosine nanoemulsions inhibit tumor growth of triple negative breast cancer in zebrafish xenograft model

Scientific Reports ◽

10.1038/s41598-021-87968-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sofia M. Saraiva ◽

Carlha Gutiérrez-Lovera ◽

Jeannette Martínez-Val ◽

Sainza Lores ◽

Belén L. Bouzo ◽

...

Keyword(s):

Breast Cancer ◽

Tumor Growth ◽

Triple Negative Breast Cancer ◽

Triple Negative ◽

Xenograft Model ◽

Skin Barrier ◽

Zebrafish Embryos ◽

Biorelevant Media

AbstractTriple negative breast cancer (TNBC) is known for being very aggressive, heterogeneous and highly metastatic. The standard of care treatment is still chemotherapy, with adjacent toxicity and low efficacy, highlighting the need for alternative and more effective therapeutic strategies. Edelfosine, an alkyl-lysophospholipid, has proved to be a promising therapy for several cancer types, upon delivery in lipid nanoparticles. Therefore, the objective of this work was to explore the potential of edelfosine for the treatment of TNBC. Edelfosine nanoemulsions (ET-NEs) composed by edelfosine, Miglyol 812 and phosphatidylcholine as excipients, due to their good safety profile, presented an average size of about 120 nm and a neutral zeta potential, and were stable in biorelevant media. The ability of ET-NEs to interrupt tumor growth in TNBC was demonstrated both in vitro, using a highly aggressive and invasive TNBC cell line, and in vivo, using zebrafish embryos. Importantly, ET-NEs were able to penetrate through the skin barrier of MDA-MB 231 xenografted zebrafish embryos, into the yolk sac, leading to an effective decrease of highly aggressive and invasive tumoral cells’ proliferation. Altogether the results demonstrate the potential of ET-NEs for the development of new therapeutic approaches for TNBC.

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Engineered IL-7 Receptor Enhances the Therapeutic Effect of AXL-CAR-T Cells on Triple-Negative Breast Cancer

BioMed Research International ◽

10.1155/2020/4795171 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13 ◽

Cited By ~ 2

Author(s):

Zhenhui Zhao ◽

Yan Li ◽

Wei Liu ◽

Xun Li

Keyword(s):

Breast Cancer ◽

T Cells ◽

Triple Negative Breast Cancer ◽

Triple Negative ◽

Xenograft Model ◽

Target Cells ◽

Car T Cells ◽

Car T

Triple-negative breast cancer (TNBC) is a very aggressive malignant type of tumor that currently lacks effective targeted therapies. In hematological malignancies, chimeric antigen receptor T (CAR-T) cells have shown very significant antitumor ability; however, in solid tumors, the efficacy is poor. In order to apply CAR-T cells in the treatment of TNBC, in this study, constitutively activated IL-7 receptor (C7R) that has been reported is used to enhance the antitumor function of constructed CAR-T cells by ourselves. Using in vitro coincubation experiments with target cells and in vivo antitumor experiments in mice, we found that the coexpressed C7R can significantly improve the activation, cell proliferation, and cytotoxicity of CAR-T cells. In addition, the in vivo experiments suggested that the enhanced CAR-T cells displayed significant antitumor activity in a TNBC subcutaneous xenograft model, in which in vivo, the survival time of CAR-T cells was prolonged. Together, these results indicated that CAR-T cells that coexpress C7R may be a novel therapeutic strategy for TNBC.

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Anti-tumor activity of BET inhibitors in androgen-receptor-expressing triple-negative breast cancer

Scientific Reports ◽

10.1038/s41598-019-49366-9 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 1

Author(s):

In Hae Park ◽

Han Na Yang ◽

Su Yeon Jeon ◽

Jung-Ah Hwang ◽

Min Kyeong Kim ◽

...

Keyword(s):

Breast Cancer ◽

Cell Cycle ◽

Androgen Receptor ◽

Triple Negative Breast Cancer ◽

Triple Negative ◽

Xenograft Model ◽

Bet Inhibitor ◽

Bet Inhibitors ◽

Anti Tumor Activity

Abstract Triple-negative breast cancer (TNBC) is a heterogeneous disease comprising several subtypes. Androgen-receptor (AR) signaling has been targeted by several investigational agents in luminal AR subtype TNBCs. Bromodomain (BRD) and extra-terminal motif (BET) protein inhibitors have been shown to attenuate AR signaling in metastatic castration-resistant prostate cancer and to overcome enzalutamide resistance. We demonstrated potent anti-tumor effects of the BET inhibitor JQ1 against AR-positive TNBC cell lines using cell viability and cell cycle analysis. To reveal the mechanisms of JQ1 effects, multiplex gene expression analysis and immunoblotting assays were used. We examined in vivo effects of JQ1 in a xenograft model of AR expressing TNBC. JQ1 exhibited its anti-proliferative activity by inducing apoptosis and cell cycle arrest. JQ1 activity was not mediated by MYC downregulation. Instead, JQ1 blocked the interactions among the ATPase-family AAA-domain-containing 2 protein (ATAD2), BRD2, BRD4, and AR; effectively suppressing the expression of AR associated targets. In addition, JQ1 showed significant anti-tumor activity in vivo in TNBC xenograft mouse models as a monotherapy and in combination with anti-AR therapy. Taken together, our results showed that the BET inhibitor JQ1 is a promising therapeutic agent for the treatment of AR-positive TNBC.

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BRD4 modulates vulnerability of triple-negative breast cancer to targeting of integrin-dependent signaling pathways

Cellular Oncology ◽

10.1007/s13402-020-00537-1 ◽

2020 ◽

Vol 43 (6) ◽

pp. 1049-1066

Author(s):

Yang Zhang ◽

Bingwei Xu ◽

Junfeng Shi ◽

Jieming Li ◽

Xinlan Lu ◽

...

Keyword(s):

Breast Cancer ◽

Clinical Outcomes ◽

Cell Lines ◽

Cancer Cell ◽

Triple Negative Breast Cancer ◽

Triple Negative ◽

Therapeutic Potential ◽

Apoptotic Cell ◽

Xenograft Model

Abstract Purpose Stemming from a myriad of genetic and epigenetic alterations, triple-negative breast cancer (TNBC) is tied to poor clinical outcomes and aspires for individualized therapies. Here we investigated the therapeutic potential of co-inhibiting integrin-dependent signaling pathway and BRD4, a transcriptional and epigenetic mediator, for TNBC. Methods Two independent patient cohorts were subjected to bioinformatic and IHC examination for clinical association of candidate cancer drivers. The efficacy and biological bases for co-targeting these drivers were interrogated using cancer cell lines, a protein kinase array, chemical inhibitors, RNAi/CRISPR/Cas9 approaches, and a 4 T1-Balb/c xenograft model. Results We found that amplification of the chromosome 8q24 region occurred in nearly 20% of TNBC tumors, and that it coincided with co-upregulation or amplification of c-Myc and FAK, a key effector of integrin-dependent signaling. This co-upregulation at the mRNA or protein level correlated with a poor patient survival (p < 0.0109 or p < 0.0402, respectively). Furthermore, we found that 14 TNBC cell lines exhibited high vulnerabilities to the combination of JQ1 and VS-6063, potent pharmacological antagonists of the BRD4/c-Myc and integrin/FAK-dependent pathways, respectively. We also observed a cooperative inhibitory effect of JQ1 and VS-6063 on tumor growth and infiltration of Ly6G+ myeloid-derived suppressor cells in vivo. Finally, we found that JQ1 and VS-6063 cooperatively induced apoptotic cell death by altering XIAP, Bcl2/Bcl-xl and Bim levels, impairing c-Src/p130Cas-, PI3K/Akt- and RelA-associated signaling, and were linked to EMT-inducing transcription factor Snail- and Slug-dependent regulation. Conclusion Based on our results, we conclude that the BRD4/c-Myc- and integrin/FAK-dependent pathways act in concert to promote breast cancer cell survival and poor clinical outcomes. As such, they represent promising targets for a synthetic lethal-type of therapy against TNBC.

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The testis protein ZNF165 is a SMAD3 cofactor that coordinates oncogenic TGFβ signaling in triple-negative breast cancer

eLife ◽

10.7554/elife.57679 ◽

2020 ◽

Vol 9 ◽

Author(s):

Zane A Gibbs ◽

Luis C Reza ◽

Chun-Chun Cheng ◽

Jill M Westcott ◽

Kathleen McGlynn ◽

...

Keyword(s):

Breast Cancer ◽

Triple Negative Breast Cancer ◽

Triple Negative ◽

Transforming Growth Factor ◽

Zinc Finger Protein ◽

Xenograft Model ◽

Transforming Growth Factor Β ◽

Aberrant Expression ◽

Orthotopic Xenograft Model

Cancer/testis (CT) antigens are proteins whose expression is normally restricted to germ cells yet aberrantly activated in tumors, where their functions remain relatively cryptic. Here we report that ZNF165, a CT antigen frequently expressed in triple-negative breast cancer (TNBC), associates with SMAD3 to modulate transcription of transforming growth factor β (TGFβ)-dependent genes and thereby promote growth and survival of human TNBC cells. In addition, we identify the KRAB zinc finger protein, ZNF446, and its associated tripartite motif protein, TRIM27, as obligate components of the ZNF165-SMAD3 complex that also support tumor cell viability. Importantly, we find that TRIM27 alone is necessary for ZNF165 transcriptional activity and is required for TNBC tumor growth in vivo using an orthotopic xenograft model in immunocompromised mice. Our findings indicate that aberrant expression of a testis-specific transcription factor is sufficient to co-opt somatic transcriptional machinery to drive a pro-tumorigenic gene expression program in TNBC.

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GCH1 induces immunosuppression through metabolic reprogramming and IDO1 upregulation in triple-negative breast cancer

Journal for ImmunoTherapy of Cancer ◽

10.1136/jitc-2021-002383 ◽

2021 ◽

Vol 9 (7) ◽

pp. e002383

Author(s):

Jin-Li Wei ◽

Si-Yu Wu ◽

Yun-Song Yang ◽

Yi Xiao ◽

Xi Jin ◽

...

Keyword(s):

Breast Cancer ◽

Triple Negative Breast Cancer ◽

Triple Negative ◽

Molecular Taxonomy ◽

Underlying Mechanism ◽

Metabolic Reprogramming ◽

Sequencing Data ◽

Aryl Hydrocarbon

PurposeRegulatory T cells (Tregs) heavily infiltrate triple-negative breast cancer (TNBC), and their accumulation is affected by the metabolic reprogramming in cancer cells. In the present study, we sought to identify cancer cell-intrinsic metabolic modulators correlating with Tregs infiltration in TNBC.Experimental designUsing the RNA-sequencing data from our institute (n=360) and the Molecular Taxonomy of Breast Cancer International Consortium TNBC cohort (n=320), we calculated the abundance of Tregs in each sample and evaluated the correlation between gene expression levels and Tregs infiltration. Then, in vivo and in vitro experiments were performed to verify the correlation and explore the underlying mechanism.ResultsWe revealed that GTP cyclohydrolase 1 (GCH1) expression was positively correlated with Tregs infiltration and high GCH1 expression was associated with reduced overall survival in TNBC. In vivo and in vitro experiments showed that GCH1 increased Tregs infiltration, decreased apoptosis, and elevated the programmed cell death-1 (PD-1)-positive fraction. Metabolomics analysis indicated that GCH1 overexpression reprogrammed tryptophan metabolism, resulting in L-5-hydroxytryptophan (5-HTP) accumulation in the cytoplasm accompanied by kynurenine accumulation and tryptophan reduction in the supernatant. Subsequently, aryl hydrocarbon receptor, activated by 5-HTP, bound to the promoter of indoleamine 2,3-dioxygenase 1 (IDO1) and thus enhanced the transcription of IDO1. Furthermore, the inhibition of GCH1 by 2,4-diamino-6-hydroxypyrimidine (DAHP) decreased IDO1 expression, attenuated tumor growth, and enhanced the tumor response to PD-1 blockade immunotherapy.ConclusionsTumor-cell-intrinsic GCH1 induced immunosuppression through metabolic reprogramming and IDO1 upregulation in TNBC. Inhibition of GCH1 by DAHP serves as a potential immunometabolic strategy in TNBC.

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A novel humanized Frizzled-7-targeting antibody enhances antitumor effects of Bevacizumab against triple-negative breast cancer via blocking Wnt/β-catenin signaling pathway

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-020-01800-x ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Wei Xie ◽

Huijie Zhao ◽

Fengxian Wang ◽

Yiyun Wang ◽

Yuan He ◽

...

Keyword(s):

Breast Cancer ◽

Triple Negative Breast Cancer ◽

Molecular Mechanisms ◽

Near Infrared ◽

Triple Negative ◽

Vasculogenic Mimicry ◽

Xenograft Model ◽

Luciferase Reporter ◽

Antitumor Effects ◽

Mouse Xenograft Model

Abstract Background Anti-angiogenic therapy has been widely applied to the clinical treatment of malignant tumors. However, the efficacy of such treatments has been called into question, especially in triple-negative breast cancer (TNBC). Bevacizumab, the first anti-angiogenic agent approved by FDA, actually increases invasive and metastatic properties of TNBC cells, resulting from the activation of Wnt/β-catenin signaling in response to hypoxia. As a critical receptor of Wnt/β-catenin signaling, Frizzled-7 (Fzd7) is aberrantly expressed in TNBC, indicating Fzd7 a potential target for developing drugs to be combined with anti-angiogenic agents. Methods Hybridoma technique and antibody humanization technique were utilized to generate a Fzd7-targeting antibody (SHH002-hu1). Biolayer interferometry (BLI) assay and near infrared (NIR) imaging were conducted to detect the affinity and targeting ability of SHH002-hu1. Next, whether SHH002-hu1 could suppress the invasion and migration of TNBC cells induced by Bevacizumab were validated, and the underlying molecular mechanisms were elucidated by luciferase reporter and western blot assays. The nude-mice transplanted TNBC models were established to assess the anti-TNBC activities of SHH002-hu1 when combined with Bevacizumab. Then, the effects on putative TNBC stem-like cells and Wnt/β-catenin signaling were evaluated by immunofluorescence (IF). Further, the tumor-initiating and self-renew capacity of TNBC cells were studied by secondary nude mouse xenograft model and sphere formation assay. In addition, the effects of SHH002-hu1 on the adaptation of TNBC cells to hypoxia were evaluated by the detection of vasculogenic mimicry (VM) and hypoxia-inducible factor-1α (HIF-1α) transcriptional activity. Results The novel humanized antibody targeting Fzd7 (SHH002-hu1) exhibited extremely high affinity with Fzd7, and specifically targeted to Fzd7+ cells and tumor tissues. SHH002-hu1 repressed invasion, migration and epithelial-mesenchymal cell transformation (EMT) of TNBC cells induced by Bevacizumab through abating Wnt/β-catenin signaling. SHH002-hu1 significantly enhanced the capacity of Bevacizumab to inhibit the growth of TNBC via reducing the subpopulation of putative TNBC stem-like cells, further attenuating Bevacizumab-enhanced tumor-initiating and self-renew capacity of TNBC cells. Moreover, SHH002-hu1 effectively restrained the adaptation of TNBC cells to hypoxia via disrupting Wnt/β-catenin signaling. Conclusion SHH002-hu1 significantly enhances the anti-TNBC capacity of Bevacizumab, and shows the potential of preventing TNBC recurrence, suggesting SHH002-hu1 a good candidate for the synergistic therapy together with Bevacizumab.

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MiR-211 determines brain metastasis specificity through SOX11/NGN2 axis in triple-negative breast cancer

Oncogene ◽

10.1038/s41388-021-01654-3 ◽

2021 ◽

Author(s):

Jhih-Kai Pan ◽

Cheng-Han Lin ◽

Yao-Lung Kuo ◽

Luo-Ping Ger ◽

Hui-Chuan Cheng ◽

...

Keyword(s):

Breast Cancer ◽

Brain Metastasis ◽

Triple Negative Breast Cancer ◽

Triple Negative ◽

Survival Outcomes ◽

Poor Survival ◽

Breast Cancer Brain Metastasis ◽

High Level

AbstractBrian metastasis, which is diagnosed in 30% of triple-negative breast cancer (TNBC) patients with metastasis, causes poor survival outcomes. Growing evidence has characterized miRNAs involving in breast cancer brain metastasis; however, currently, there is a lack of prognostic plasma-based indicator for brain metastasis. In this study, high level of miR-211 can act as brain metastatic prognostic marker in vivo. High miR-211 drives early and specific brain colonization through enhancing trans-blood–brain barrier (BBB) migration, BBB adherence, and stemness properties of tumor cells and causes poor survival in vivo. SOX11 and NGN2 are the downstream targets of miR-211 and negatively regulate miR-211-mediated TNBC brain metastasis in vitro and in vivo. Most importantly, high miR-211 is correlated with poor survival and brain metastasis in TNBC patients. Our findings suggest that miR-211 may be used as an indicator for TNBC brain metastasis.

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Multiple screening approaches reveal HDAC6 as a novel regulator of glycolytic metabolism in triple-negative breast cancer

Science Advances ◽

10.1126/sciadv.abc4897 ◽

2021 ◽

Vol 7 (3) ◽

pp. eabc4897

Author(s):

Catríona M. Dowling ◽

Kate E. R. Hollinshead ◽

Alessandra Di Grande ◽

Justin Pritchard ◽

Hua Zhang ◽

...

Keyword(s):

Breast Cancer ◽

Triple Negative Breast Cancer ◽

Histone Deacetylase Inhibitors ◽

Triple Negative ◽

Mitochondrial Apoptosis ◽

Glycolytic Metabolism ◽

Set Up ◽

Screening Approaches

Triple-negative breast cancer (TNBC) is a subtype of breast cancer without a targeted form of therapy. Unfortunately, up to 70% of patients with TNBC develop resistance to treatment. A known contributor to chemoresistance is dysfunctional mitochondrial apoptosis signaling. We set up a phenotypic small-molecule screen to reveal vulnerabilities in TNBC cells that were independent of mitochondrial apoptosis. Using a functional genetic approach, we identified that a “hit” compound, BAS-2, had a potentially similar mechanism of action to histone deacetylase inhibitors (HDAC). An in vitro HDAC inhibitor assay confirmed that the compound selectively inhibited HDAC6. Using state-of-the-art acetylome mass spectrometry, we identified glycolytic substrates of HDAC6 in TNBC cells. We confirmed that inhibition or knockout of HDAC6 reduced glycolytic metabolism both in vitro and in vivo. Through a series of unbiased screening approaches, we have identified a previously unidentified role for HDAC6 in regulating glycolytic metabolism.

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CircWAC induces chemotherapeutic resistance in triple-negative breast cancer by targeting miR-142, upregulating WWP1 and activating the PI3K/AKT pathway

Molecular Cancer ◽

10.1186/s12943-021-01332-8 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Lei Wang ◽

Yehui Zhou ◽

Liang Jiang ◽

Linlin Lu ◽

Tiantian Dai ◽

...

Keyword(s):

Breast Cancer ◽

Triple Negative Breast Cancer ◽

Triple Negative ◽

Luciferase Reporter ◽

Akt Pathway ◽

Circular Rnas ◽

Chemotherapeutic Resistance ◽

Repressive Effect

Abstract Background Chemotherapeutic resistance is the main cause of clinical treatment failure and poor prognosis in triple-negative breast cancer (TNBC). There is no research on chemotherapeutic resistance in TNBC from the perspective of circular RNAs (circRNAs). Methods TNBC-related circRNAs were identified based on the GSE101124 dataset. Quantitative reverse transcription PCR was used to detect the expression level of circWAC in TNBC cells and tissues. Then, in vitro and in vivo functional experiments were performed to evaluate the effects of circWAC in TNBC. Results CircWAC was highly expressed in TNBC and was associated with worse TNBC patient prognosis. Subsequently, it was verified that downregulation of circWAC can increase the sensitivity of TNBC cells to paclitaxel (PTX) in vitro and in vivo. The expression of miR-142 was negatively correlated with circWAC in TNBC. The interaction between circWAC and miR-142 in TNBC cells was confirmed by RNA immunoprecipitation assays, luciferase reporter assays, pulldown assays, and fluorescence in situ hybridization. Mechanistically, circWAC acted as a miR-142 sponge to relieve the repressive effect of miR-142 on its target WWP1. In addition, the overall survival of TNBC patients with high expression of miR-142 was significantly better than that of patients with low expression of miR-142, and these results were verified in public databases. MiR-142 regulated the expression of WWP1 and the activity of the PI3K/AKT pathway. It was confirmed that WWP1 is highly expressed in TNBC and that the prognosis of patients with high WWP1 expression is poor. Conclusions CircWAC/miR-142/WWP1 form a competing endogenous RNA (ceRNA) network to regulate PI3K/AKT signaling activity in TNBC cells and affect the chemosensitivity of cells.

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