scholarly journals Cell Cytoskeleton and Stiffness Are Mechanical Indicators of Organotropism in Breast Cancer

Biology ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 259
Author(s):  
Kai Tang ◽  
Ying Xin ◽  
Keming Li ◽  
Xi Chen ◽  
Youhua Tan
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Tumor Cells ◽  
Breast Cancer Cells ◽  
Gene Expression Pattern ◽  
Cell Stiffness ◽  
Subsequent Formation ◽  
Cell Cytoskeleton ◽  
The Difference

Tumor metastasis involves the dissemination of tumor cells from the primary lesion to other organs and the subsequent formation of secondary tumors, which leads to the majority of cancer-related deaths. Clinical findings show that cancer cell dissemination is not random but exhibits organ preference or organotropism. While intrinsic biochemical factors of cancer cells have been extensively studied in organotropism, much less is known about the role of cell cytoskeleton and mechanics. Herein, we demonstrate that cell cytoskeleton and mechanics are correlated with organotropism. The result of cell stiffness measurements shows that breast cancer cells with bone tropism are much stiffer with enhanced F-actin, while tumor cells with brain tropism are softer with lower F-actin than their parental cells. The difference in cellular stiffness matches the difference in the rigidity of their metastasized organs. Further, disrupting the cytoskeleton of breast cancer cells with bone tropism not only elevates the expressions of brain metastasis-related genes but also increases cell spreading and proliferation on soft substrates mimicking the stiffness of brain tissue. Stabilizing the cytoskeleton of cancer cells with brain tropism upregulates bone metastasis-related genes while reduces the mechanoadaptation ability on soft substrates. Taken together, these findings demonstrate that cell cytoskeleton and biophysical properties of breast cancer subpopulations correlate with their metastatic preference in terms of gene expression pattern and mechanoadaptation ability, implying the potential role of cell cytoskeleton in organotropism.

scholarly journals S100A10 has a Critical Regulatory Function in Mammary Tumor Growth and Metastasis: Insights using MMTV-PyMT Oncomice and Clinical Patient Sample Analysis.

2020 ◽  
Author(s):  
Alamelu G Bharadwaj ◽  
Margaret L Dahn ◽  
Ron-Zong Liu ◽  
Patricia Colp ◽  
Lynn N Thomas ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Tumor Cells ◽  
Human Breast Cancer ◽  
Breast Cancer Cells ◽  
Triple Negative ◽  
Invasive Carcinoma ◽  
Human Breast ◽  
Tumor Growth And Metastasis

Abstract Background: Breast cancer is one of the leading causes of cancer deaths in women worldwide. Significant advances have been made in the diagnosis and treatment of breast cancer, treatment of triple-negative and metastatic breast cancer poses significant challenge. Metastasis is a multi-step cascade that involves activation of proteases such as plasmin to facilitate the invasive escape of tumor cells to distant organs. The rate-limiting step in plasmin generation requires the interaction of plasminogen with cell surface plasminogen binding sites. Our laboratory first demonstrated that the plasminogen receptor, S100A10 (p11) was upregulated in many cancer cells and was responsible for much of their plasmin generation. Recently, it was reported that p11 is one of a few genes that are activated when human breast cancer cells metastasize from the primary tumor into the blood and is upregulated during the conversion of breast cancer cells to invasive phenotype. In the current study we have investigated the role of p11 in breast cancer tumor progression.Methods: We have used MMTV-PyMT a mouse transgenic mammary tumor model to investigate the effects of loss of p11 on spontaneous tumor initiation, growth and progression to invasive carcinoma and metastasis. We used experimental metastasis assays to ascertain the role of stromal p11 in tumor cell extravasation and lung colonization. Genes and cytokines regulated by p11 in the PyMT tumors were assessed by microarray analysis and RT-qPCR. Finally, we employed gene profiling analysis and immunohistochemical staining of breast cancer patient tumors to correlate p11 expression to human breast cancer progression. Results: Genetic deletion of p11 resulted in significantly decreased tumor onset, growth rate, and spontaneous pulmonary metastatic burden in the PyMT/p11-KO mice. This phenotype was accompanied by substantial reduction in Ki67 positivity, macrophage infiltration, decreased vascular density in the primary tumors and decrease in invasive carcinoma and pulmonary metastasis. Surprisingly, immunohistochemical analysis of wild-type MMTV-PyMT mice failed to detect p11 expression in the tumors or metastatic tumor cells and loss of p11 did not decrease plasmin generation in the PyMT tumors and cells. Furthermore, tumor cells expressing p11 displayed dramatically reduced lung metastasis when injected into p11-depleted mice, further strengthening the stromal role of p11 in tumor growth and metastasis. Transcriptome analysis of the PyMT tumors from p11-KO mice showed marked reduction in genes involved in breast cancer development, progression, and inflammation such as AREG, MUC1 and S100A8. The PyMT/p11- KO tumors displayed a remarkable increase in inflammatory cytokines such as IL-6, IL-10 and IFN-γ. Gene expression profiling from 176 primary breast cancer samples obtained through the CBCF tumor bank showed that p11 mRNA levels were significantly higher in tumors compared to normal tissues. P11 mRNA expression was significantly associated with poor patient prognosis (hazard ratio – 3.34) and significantly elevated in high grade, triple negative (TN) tumors, and tumors with high proliferative index. Evaluation of p11 protein expression in a NSHA cohort of patients revealed substantial upregulation of p11 in cancer tissues compared to normal controls. Conclusions: This is the first study demonstrating the crucial role of p11 in breast tumor development and metastasis. The results emphasize the potential of p11 as a diagnostic and prognostic biomarker in breast cancer.

scholarly journals The role of mTOR in SAF-1-mediated VEGF expression and breast cancer progression

2015 ◽  
Author(s):  
◽  
Mohamed Alalem
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Tumor Cells ◽  
Breast Cancer Cells ◽  
Vegf Expression ◽  
Mtor Inhibition ◽  
Mtor Protein ◽  
And Migration ◽  
Proliferation And Migration

Breast cancer is a heterogeneous disease with a huge impact on the community evident from its high indices of morbidity and mortality worldwide. In recent years, research has been extensively directed toward unravelling the molecular basis of the pathogenesis in different molecular subtypes of breast cancer. Better understanding of the different breast cancer cells and the subsequent improvement of diagnostic and therapeutic modalities of the disease resulted in a promising decline in its morbidity and mortality. In addition to surgery, radiotherapy, and conventional chemotherapy, treatment of breast cancer, nowadays, involves more targeted therapeutic options. Treatment options of breast cancer are determined mainly by the tumor stage and molecular subtypes of the tumor cells. Invasive potentials of a tumor involve also its ability to recruit blood supply through a process known as angiogenesis. Angiogenesis is an intricate process mediated by the interaction of many players including the tumor cells and stroma as well as the endothelial cells in adjacent blood vessels. Vascular endothelial growth factor (VEGF) is one of the main proangiogenic molecules secreted by breast cancer cells to promote angiogenesis through binding to the vascular endothelial growth factor receptors (VEGFR) on target cells. Although angiogenesis is a hallmark of invasive solid tumors, it is also required in some normal physiological conditions. Targeting angiogenesis indiscriminately imposes a huge risk of enormous adverse effects. Therefore, the goal of research today is to explore potential mechanisms to counteract angiogenesis selectively in the tumor cells. Secretion of VEGF by breast cancer cells is activated by several stimuli including hypoxia, metabolic stress and inflammatory conditions. Hypoxia is one of the main drivers for both physiological and pathological angiogenesis. Hypoxia induces VEGF expression in hypoxic cells through the action of hypoxia inducible factor-1 (HIF-1). However, evidence indicates that breast cancer cells are capable of secreting VEGF at early stages before hypoxia ensues in the tumor mass. Evidence shows also that breast cancer cells secrete VEGF even under normoxic conditions, which suggests that VEGF expression in breast cancer, particularly at early stages, is mediated by a mechanism(s) other than hypoxia. The goal of our research is to investigate some of these potential mechanism(s). Unravelling these mechanism(s) could pave the road for potentially novel therapeutic modalities in the treatment of breast cancer. Previous work in our lab has identified a role of serum amyloid activating factor-1 (SAF-1), a transcription factor, in overexpression of VEGF in some breast cancer cells. Here, we report that the SAF-1-mediated VEGF expression in breast cancer cells is repressed by Kruppel like factor-4 (KLF-4) transcription factor. Our findings suggest also that KLF-4 is potentially involved in the repression of the VEGF expression in a SAF-1-independent manner. We found that the level of KLF-4 is lower in breast cancer cells compared to normal breast cells. Therefore, we further investigated possible mechanism(s) for upregulation of KLF-4 or downregulation of SAF-1 in breast cancer cells to curtail VEGF expression and counteract angiogenesis and thence progression of breast cancer. There is evidence in literature that inhibition of a serine-threonine kinase called mammalian target of rapamycin (mTOR) exerts antiproliferative effect in vascular smooth muscle cells (VSMC). Evidence showed that the effect of mTOR inhibition on VSMC is mediated by upregulation of KLF-4 through a yet unknown mechanism. Thus, we have explored a potential role of mTOR inhibition in upregulation of KLF-4 in breast cancer cells and inhibition of VEGF expression. VEGF secreted by breast cancer cells not only stimulates proliferation and migration of the endothelial cells, but also promotes proliferation and migration of the secreting breast cancer cells themselves. Mounting evidence substantiates the beneficial role of mTOR inhibition in breast cancer. Our results show a novel mechanism of upregulating KLF-4 and inhibition of VEGF expression in breast cancer cells through inhibition of mTOR. Nonetheless, we noted that the effects of mTOR inhibition on breast cancer cells, including upregulation of KLF-4 and inhibition of proliferation and migration, are variable among different breast cell lines as well as among different mTOR inhibitors. One of the possible explanation of the variable response to mTOR inhibitors is the rebound upregulation of proteins in the mTOR pathway which imposes a risk of emergence of resistance or refractoriness to treatment with mTOR inhibition. The role of active mTOR in the invasiveness of breast cancer is well known, yet relatively little is known about the role and impact of total mTOR protein. We found that total mTOR protein level is higher in breast cancer cells compared to their noncancerous counterparts. mTOR protein is particularly high in the ER+ breast cancer cells which constitute the majority of breast cancer cells subtypes. High mTOR protein level in breast cancer cells could be attributed to decreased mTOR protein degradation, increased mTOR gene expression, or both. Our results indicate a defective degradation of mTOR in breast cancer cells compared to normal cells, which could, at least in part, explain why mTOR protein is high in breast cancer cells. Our results show also that transcription of mTOR gene is elevated in the ER+ breast cancer cells. Our study revealed that promoter region of mTOR in the ER+ breast cancer cells has a truncated dinucleotide tandem repeat region. Tandem repeats are a potential site for regulation of transcription of genes. Shortening of this region could be a possible mechanism of increased transcription of mTOR gene in the ER+ breast cancer cells. Moreover, we have revealed a novel mechanism of increasing mTOR degradation as well as inhibition of MTOR transcription in the ER+ breast cancer cells by treatment with metformin the antidiabetic mTOR inhibitor. In correlation, metformin treatment induced a profound effect on upregulation of KLF-4 and inhibition of proliferation and migration of the breast cancer cells, particularly, the ER+ subtype. These findings could be utilized in the optimization of chemotherapeutic regimens of breast cancer.

scholarly journals 931 LncRNA Malat1 regulated Serpinb6b signaling suppresses pyroptosis and governs breast cancer dormancy reactivation and through immune evasion

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A977-A977
Author(s):  
Dhiraj Kumar ◽  
Filippo Giancotti
Keyword(s):  
Breast Cancer ◽  
T Cells ◽  
Single Cell ◽  
Cancer Cells ◽  
Tumor Cells ◽  
Immune Evasion ◽  
Breast Cancer Cells ◽  
Rna Seq

BackgroundMetastatic relapse is the major causes of mortality in patients with cancer and occur due to metastatic reactivation of dormant tumor cells. Early dissemination of tumor cells undergoing a protected period of dormancy in the target organs potentially explains this prevalent clinical behavior.1–4 Long non-coding RNAs (lncRNAs) are involved in various biological processes and diseases. Malat1 is one of the most abundant and highly conserved nuclear lncRNAs and have shown the associated with metastasis and serving as a predictive marker for various tumor progression.5 However, the correlation of tumor intrinsic lncRNAs in regulation of tumor dormancy and immune evasion is largely unknown.MethodsUsing an in vivo screening platform for the isolation of genetic entities involved in either dormancy or reactivation of breast cancer tumor cells, we have identified Malat1 as a positive mediator of metastatic reactivation.4 To dissect the functional role of Malat1 in metastatic reactivation, we developed a clean Malat1 knockout (KO) model using paired gRNA CRISPR-Cas9 in metastatic murine syngeneic breast cancer. As proof of concept we also used inducible knockdown system under in vivo models. To delineate the immune microenvironment, we used single cell RNA-seq, ChIRP-seq, multicolor flowcytometry, RNA-FISH, and coculture experiments.ResultsOur data revealed that deletion of Malat1 induces dormancy and attenuated the metastatic colonization resulting in long-term survival of syngeneic mice model. In contrast, overexpression of Malat1 leads to metastatic reactivation of dormant breast cancer cells. Interestingly, 4T1-Malat1 KO dormant breast cancer cells exhibit metastatic outgrowth in T cells defective mice. Our single-cell RNA-seq and multicolor flowcytometry evaluation reveal enhanced T cells and reduced neutrophils proportions in mice with Malat1 KO cells. This indicates a critical role of immune microenvironment via Malat1-dependent immune evasion. Additionally, Malat1 KO inhibits cancer stemness properties. Similarly, RNA-seq and ChIRP-seq data suggest that KO of Malat1 hampers immune evasion and downregulates metastasis associated genes including Serpins and Wnts. Additionally, our data strongly suggests that Malat1 KO cells persists as non-proliferative dormant cells in lung due to CD8+ T cell-umpired immune activity. Interestingly, rescue experiments suggest that Malat1 or Serpinb6b protects T cell-induced cell death and induces dormancy re-awakening thereby rescue the metastatic potential of 4T1 Malat1 KO cells. Combination of Malat1 ASO with double immune checkpoint inhibitors greatly affects the metastatic outgrowth in breast cancer.ConclusionsTaken together, our studies demonstrate that tumor intrinsic Malat1 regulates Serpinb6b that eventually controls immune evasion and promote dormancy metastatic reactivation.AcknowledgementsNGS data generated was supported by Core grant CA016672(ATGC) and NIH 1S10OD024977-01 award to the ATGC. Single cell RNA sequencing data was supported by the CPRIT Single Core grant RP180684. The Advanced Cytometry & Sorting Core Facility is supported by NCI P30CA016672.ReferencesArun G, Diermeier S, Akerman M, et al. Differentiation of mammary tumors and reduction in metastasis upon Malat1 lncRNA loss. Genes Dev 2016 January 1;30(1):34–51.Filippo G Giancotti. Mechanisms governing metastatic dormancy and reactivation. Cell 2013 November 7;155(4):750–764.Gao H, Chakraborty G, Lee-Lim AP, et al. The BMP inhibitor Coco reactivates breast cancer cells at lung metastatic sites. Cell 2012b;150:764–779.Gao H, Chakraborty G, Lee-Lim AP, et al. Forward genetic screens in mice uncover mediators and suppressors of metastatic reactivation. Proc Natl Acad Sci U S A 2014 November 18;111(46):16532–16537.Huang D, Chen J, Yang L, et al. NKILA lncRNA promotes tumor immune evasion by sensitizing T cells to activation-induced cell death. Nat Immunol 2018;19:1112–1125.

Recent Advances on Therapeutic Peptides for Breast Cancer Treatment

2020 ◽  
Vol 21 ◽  
Author(s):  
Samad Beheshtirouy ◽  
Farhad Mirzaei ◽  
Shirin Eyvazi ◽  
Vahideh Tarhriz
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Tumor Cells ◽  
Breast Cancer Cells ◽  
Specific Binding ◽  
High Specificity ◽  
The Novel ◽  
Anti Cancer ◽  
Therapeutic Peptides ◽  
Low Toxicity

: Breast cancer is a heterogeneous malignancy which is the second cause of mortality among women in the world. Increasing the resistance to anti-cancer drugs in breast cancer cells persuades researchers to search the novel therapies approaches for the treatment of the malignancy. Among the novel methods, therapeutic peptides which target and disrupt tumor cells have been of great interest. Therapeutic peptides are short amino acids monomer chains with high specificity to bind and modulate a protein interaction of interest. Several advantages of peptides such as specific binding on tumor cells surface, low molecular weight and low toxicity on normal cells make the peptides as an appealing therapeutic agents against solid tumors, particularly breast cancer. Also, National Institutes of Health (NIH) describes therapeutic peptides as suitable candidate for the treatment of drug-resistant breast cancer. In this review, we attempt to review the different therapeutic peptides against breast cancer cells which can be used in treatment and diagnosis of the malignancy. Meanwhile, we presented an overview of peptide vaccines which have been developed for the treatment of breast cancer.

scholarly journals Matrix degradation and cell proliferation are coupled to promote invasion and escape from an engineered human breast microtumor

2021 ◽  
Vol 13 (1) ◽  
pp. 17-29
Author(s):  
Emann M Rabie ◽  
Sherry X Zhang ◽  
Andreas P Kourouklis ◽  
A Nihan Kilinc ◽  
Allison K Simi ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Cycle ◽  
Cell Proliferation ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Type I ◽  
Matrix Degradation ◽  
Human Breast ◽  
Rate Of Invasion

Abstract Metastasis, the leading cause of mortality in cancer patients, depends upon the ability of cancer cells to invade into the extracellular matrix that surrounds the primary tumor and to escape into the vasculature. To investigate the features of the microenvironment that regulate invasion and escape, we generated solid microtumors of MDA-MB-231 human breast carcinoma cells within gels of type I collagen. The microtumors were formed at defined distances adjacent to an empty cavity, which served as an artificial vessel into which the constituent tumor cells could escape. To define the relative contributions of matrix degradation and cell proliferation on invasion and escape, we used pharmacological approaches to block the activity of matrix metalloproteinases (MMPs) or to arrest the cell cycle. We found that blocking MMP activity prevents both invasion and escape of the breast cancer cells. Surprisingly, blocking proliferation increases the rate of invasion but has no effect on that of escape. We found that arresting the cell cycle increases the expression of MMPs, consistent with the increased rate of invasion. To gain additional insight into the role of cell proliferation in the invasion process, we generated microtumors from cells that express the fluorescent ubiquitination-based cell cycle indicator. We found that the cells that initiate invasions are preferentially quiescent, whereas cell proliferation is associated with the extension of invasions. These data suggest that matrix degradation and cell proliferation are coupled during the invasion and escape of human breast cancer cells and highlight the critical role of matrix proteolysis in governing tumor phenotype.

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