Cellular Senescence limits Translational Readthrough

The origin and evolution of cancer cells is considered to be mainly fueled by DNA mutations. Although translation errors could also expand the cellular proteome, their role in cancer biology remains poorly understood. Tumor suppressors called caretakers block cancer initiation and progression by preventing DNA mutations and/or stimulating DNA repair. If translational errors contribute to tumorigenesis, then caretakers genes should prevent such errors in normal cells in response to oncogenic stimuli. Here, we show that the process of cellular senescence induced by oncogenes, tumor suppressors or chemotherapeutic drugs is associated to a reduction in translational readthrough (TR) measured using reporters containing termination codons withing the context of both normal translation termination or programmed TR. Senescence reduced both basal TR and TR stimulated by aminoglycosides. Mechanistically, the reduction of TR during senescence is controlled by the RB tumor suppressor pathway. Cells that escape from cellular senescence either induced by oncogenes or chemotherapy have an increased TR. Also, breast cancer cells that escape from therapy-induced senescence express high levels of AGO1x, a TR isoform of AGO1 linked to breast cancer progression. We propose that senescence and the RB pathway reduce TR limiting proteome diversity and the expression of TR proteins required for cancer cell proliferation.

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TOPOGRAPHY MEDIATED REGULATION OF HER-2 EXPRESSION IN BREAST CANCER CELLS

Nano LIFE ◽

10.1142/s1793984412410097 ◽

2012 ◽

Vol 02 (03) ◽

pp. 1241009 ◽

Cited By ~ 5

Author(s):

AMITA DAVEREY ◽

AUSTIN C. MYTTY ◽

SRIVATSAN KIDAMBI

Keyword(s):

Breast Cancer ◽

Cell Adhesion ◽

Cancer Cells ◽

Cancer Progression ◽

Breast Tumor ◽

Cancer Biology ◽

Breast Cancer Cells ◽

Molecular Mechanisms ◽

Her 2 ◽

Micro Topography

This article demonstrates that the surface micro-topography regulates the biology of breast cancer cells, including the expression of HER-2 gene and protein. The breast tumor microenvironment is made up of heterogenous mixture of pores, ridges and collagen fibers with well defined topographical features. Although, significant progress has been achieved towards elucidating the biochemical and molecular mechanisms that underlie breast cancer progression, quantitative characterization of the associated mechanical/topographical properties and their role in breast tumor progression remains largely unexplored. Therefore, the aim of this study is to investigate the effect of topography on the adhesion and biology of breast cancer cells in in vitro cultures. Polydimethylsiloxane (PDMS) surfaces containing different topographies were coated with polyelectrolyte multilayers (PEMs) to improve cell adhesion and maintain cell culture. HER-2 expressing breast cancer cells, BT-474 and SKBr3, were cultured on these PDMS surfaces. We demonstrate that micro-topography affects the cell adhesion and distribution depending on the topography on the PDMS surfaces. We also report for the first time that surface topography down-regulates the HER-2 gene transcription and protein expression in breast cancer cells when cultured on PDMS surfaces with micro-topographies compared to the tissue culture polystyrene surface (TCPS) control. Results from this study indicate that micro-topography modulates morphology of cells, their distribution and expression of HER-2 gene and protein in breast cancer cells. This study provides a novel platform for studying the role of native topography in the progression of breast cancer and has immense potential for understanding the breast cancer biology.

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Breast Cancer Cells in Microgravity: New Aspects for Cancer Research

International Journal of Molecular Sciences ◽

10.3390/ijms21197345 ◽

2020 ◽

Vol 21 (19) ◽

pp. 7345 ◽

Cited By ~ 1

Author(s):

Mohamed Zakaria Nassef ◽

Daniela Melnik ◽

Sascha Kopp ◽

Jayashree Sahana ◽

Manfred Infanger ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Cancer Progression ◽

Cancer Biology ◽

Breast Cancer Cells ◽

De Novo ◽

Tumor Model ◽

Cancer Drug ◽

Cancer Therapies

Breast cancer is the leading cause of cancer death in females. The incidence has risen dramatically during recent decades. Dismissed as an “unsolved problem of the last century”, breast cancer still represents a health burden with no effective solution identified so far. Microgravity (µg) research might be an unusual method to combat the disease, but cancer biologists decided to harness the power of µg as an exceptional method to increase efficacy and precision of future breast cancer therapies. Numerous studies have indicated that µg has a great impact on cancer cells; by influencing proliferation, survival, and migration, it shifts breast cancer cells toward a less aggressive phenotype. In addition, through the de novo generation of tumor spheroids, µg research provides a reliable in vitro 3D tumor model for preclinical cancer drug development and to study various processes of cancer progression. In summary, µg has become an important tool in understanding and influencing breast cancer biology.

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Chemotherapy-exacerbated Breast Cancer Metastasis: A Paradox Explainable by Stress Response

10.20944/preprints201808.0489.v1 ◽

2018 ◽

Cited By ~ 1

Author(s):

Justin D. Middleton ◽

Daniel G. Stover ◽

Tsonwin Hai

Keyword(s):

Breast Cancer ◽

Stress Response ◽

Cancer Cells ◽

Cancer Progression ◽

Cancer Biology ◽

Cancer Metastasis ◽

Blood Stream ◽

Breast Cancer Metastasis ◽

Host Cells ◽

Primary Tumors

An emerging picture in cancer biology is that, paradoxically, chemotherapy can actively induce changes that favor cancer progression. These pro-cancer changes can be either inside (intrinsic) or outside (extrinsic) the cancer cells. In this review, we will discuss the extrinsic pro-cancer effect of chemotherapy; that is, the effect of chemotherapy on the non-cancer host cells to promote cancer progression. We will focus on metastasis, and will first discuss recent data from mouse models of breast cancer. Intriguingly, despite reducing the size of primary tumors, chemotherapy changes the tumor microenvironment, resulting in an increased escape of cancer cells into the blood stream. Furthermore, chemotherapry changes the tissue microenvironment at the distant sites, making it more hospitable to cancer cells upon their arrival. We will then discuss the idea and evidence that these devastating pro-metastatic effects of chemotherapy can be explained in the context of stress response. At the end, we will discuss the potential relevance of these mouse data to human breast cancer and their implication on chemotherapy in the clinic.

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Chemotherapy-Exacerbated Breast Cancer Metastasis: A Paradox Explainable by Dysregulated Adaptive-Response

International Journal of Molecular Sciences ◽

10.3390/ijms19113333 ◽

2018 ◽

Vol 19 (11) ◽

pp. 3333 ◽

Cited By ~ 13

Author(s):

Justin Middleton ◽

Daniel Stover ◽

Tsonwin Hai

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Cancer Progression ◽

Adaptive Response ◽

Cancer Biology ◽

Cancer Metastasis ◽

Blood Stream ◽

Breast Cancer Metastasis ◽

Host Cells ◽

Primary Tumors

An emerging picture in cancer biology is that, paradoxically, chemotherapy can actively induce changes that favor cancer progression. These pro-cancer changes can be either inside (intrinsic) or outside (extrinsic) the cancer cells. In this review, we will discuss the extrinsic pro-cancer effect of chemotherapy; that is, the effect of chemotherapy on the non-cancer host cells to promote cancer progression. We will focus on metastasis, and will first discuss recent data from mouse models of breast cancer. Despite reducing the size of primary tumors, chemotherapy changes the tumor microenvironment, resulting in an increased escape of cancer cells into the blood stream. Furthermore, chemotherapry changes the tissue microenvironment at the distant sites, making it more hospitable to cancer cells upon their arrival. We will then discuss the idea and evidence that these devastating pro-metastatic effects of chemotherapy can be explained in the context of adaptive-response. At the end, we will discuss the potential relevance of these mouse data to human breast cancer and their implication on chemotherapy in the clinic.

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Matrix Stiffness Modulates Metabolic Interaction between Human Stromal and Breast Cancer Cells to Stimulate Epithelial Motility

Metabolites ◽

10.3390/metabo11070432 ◽

2021 ◽

Vol 11 (7) ◽

pp. 432

Author(s):

Iván Ponce ◽

Nelson Garrido ◽

Nicolás Tobar ◽

Francisco Melo ◽

Patricio C. Smith ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Cancer Progression ◽

Stromal Cells ◽

Glucose Transporter ◽

Lactate Production ◽

Resonance Energy ◽

Metabolic Reprogramming ◽

Dependent Manner ◽

Functional Link

Breast tumors belong to the type of desmoplastic lesion in which a stiffer tissue structure is a determinant of breast cancer progression and constitutes a risk factor for breast cancer development. It has been proposed that cancer-associated stromal cells (responsible for this fibrotic phenomenon) are able to metabolize glucose via lactate production, which supports the catabolic metabolism of cancer cells. The aim of this work was to investigate the possible functional link between these two processes. To measure the effect of matrix rigidity on metabolic determinations, we used compliant elastic polyacrylamide gels as a substrate material, to which matrix molecules were covalently linked. We evaluated metabolite transport in stromal cells using two different FRET (Fluorescence Resonance Energy Transfer) nanosensors specific for glucose and lactate. Cell migration/invasion was evaluated using Transwell devices. We show that increased stiffness stimulates lactate production and glucose uptake by mammary fibroblasts. This response was correlated with the expression of stromal glucose transporter Glut1 and monocarboxylate transporters MCT4. Moreover, mammary stromal cells cultured on stiff matrices generated soluble factors that stimulated epithelial breast migration in a stiffness-dependent manner. Using a normal breast stromal cell line, we found that a stiffer extracellular matrix favors the acquisition mechanistical properties that promote metabolic reprograming and also constitute a stimulus for epithelial motility. This new knowledge will help us to better understand the complex relationship between fibrosis, metabolic reprogramming, and cancer malignancy.

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Sympathetic activity in breast cancer and metastasis: partners in crime

Bone Research ◽

10.1038/s41413-021-00137-1 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Francisco Conceição ◽

Daniela M. Sousa ◽

Joana Paredes ◽

Meriem Lamghari

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Bone Remodeling ◽

Cancer Progression ◽

Breast Cancer Cells ◽

Sympathetic Innervation ◽

Breast Cancer Progression ◽

Vicious Cycle ◽

Native Bone ◽

Cancer Management

AbstractThe vast majority of patients with advanced breast cancer present skeletal complications that severely compromise their quality of life. Breast cancer cells are characterized by a strong tropism to the bone niche. After engraftment and colonization of bone, breast cancer cells interact with native bone cells to hinder the normal bone remodeling process and establish an osteolytic “metastatic vicious cycle”. The sympathetic nervous system has emerged in recent years as an important modulator of breast cancer progression and metastasis, potentiating and accelerating the onset of the vicious cycle and leading to extensive bone degradation. Furthermore, sympathetic neurotransmitters and their cognate receptors have been shown to promote several hallmarks of breast cancer, such as proliferation, angiogenesis, immune escape, and invasion of the extracellular matrix. In this review, we assembled the current knowledge concerning the complex interactions that take place in the tumor microenvironment, with a special emphasis on sympathetic modulation of breast cancer cells and stromal cells. Notably, the differential action of epinephrine and norepinephrine, through either α- or β-adrenergic receptors, on breast cancer progression prompts careful consideration when designing new therapeutic options. In addition, the contribution of sympathetic innervation to the formation of bone metastatic foci is highlighted. In particular, we address the remarkable ability of adrenergic signaling to condition the native bone remodeling process and modulate the bone vasculature, driving breast cancer cell engraftment in the bone niche. Finally, clinical perspectives and developments on the use of β-adrenergic receptor inhibitors for breast cancer management and treatment are discussed.

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LOXL2 Inhibitors and Breast Cancer Progression

Antioxidants ◽

10.3390/antiox10020312 ◽

2021 ◽

Vol 10 (2) ◽

pp. 312

Author(s):

Sandra Ferreira ◽

Nuno Saraiva ◽

Patrícia Rijo ◽

Ana S. Fernandes

Keyword(s):

Breast Cancer ◽

Cancer Progression ◽

Cancer Biology ◽

Breast Cancer Cells ◽

Lysyl Oxidase ◽

Breast Cancer Progression ◽

Special Focus ◽

Amine Oxidases ◽

Cross Link ◽

Promising Strategy

LOX (lysyl oxidase) and lysyl oxidase like-1–4 (LOXL 1–4) are amine oxidases, which catalyze cross-linking reactions of elastin and collagen in the connective tissue. These amine oxidases also allow the cross-link of collagen and elastin in the extracellular matrix of tumors, facilitating the process of cell migration and the formation of metastases. LOXL2 is of particular interest in cancer biology as it is highly expressed in some tumors. This protein also promotes oncogenic transformation and affects the proliferation of breast cancer cells. LOX and LOXL2 inhibition have thus been suggested as a promising strategy to prevent metastasis and invasion of breast cancer. BAPN (β-aminopropionitrile) was the first compound described as a LOX inhibitor and was obtained from a natural source. However, novel synthetic compounds that act as LOX/LOXL2 selective inhibitors or as dual LOX/LOX-L inhibitors have been recently developed. In this review, we describe LOX enzymes and their role in promoting cancer development and metastases, with a special focus on LOXL2 and breast cancer progression. Moreover, the recent advances in the development of LOXL2 inhibitors are also addressed. Overall, this work contextualizes and explores the importance of LOXL2 inhibition as a promising novel complementary and effective therapeutic approach for breast cancer treatment.

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Involvement of the ERK/HIF-1α/EMT Pathway in XCL1-Induced Migration of MDA-MB-231 and SK-BR-3 Breast Cancer Cells

International Journal of Molecular Sciences ◽

10.3390/ijms22010089 ◽

2020 ◽

Vol 22 (1) ◽

pp. 89

Author(s):

Ha Thi Thu Do ◽

Jungsook Cho

Keyword(s):

Breast Cancer ◽

Cell Migration ◽

Cancer Cells ◽

Cancer Progression ◽

Chemokine Receptor ◽

Intracellular Signaling ◽

Breast Cancer Cells ◽

Epithelial Mesenchymal Transition ◽

Mitogen Activated Protein Kinase ◽

Mesenchymal Transition

Chemokine–receptor interactions play multiple roles in cancer progression. It was reported that the overexpression of X-C motif chemokine receptor 1 (XCR1), a specific receptor for chemokine X-C motif chemokine ligand 1 (XCL1), stimulates the migration of MDA-MB-231 triple-negative breast cancer cells. However, the exact mechanisms of this process remain to be elucidated. Our study found that XCL1 treatment markedly enhanced MDA-MB-231 cell migration. Additionally, XCL1 treatment enhanced epithelial–mesenchymal transition (EMT) of MDA-MB-231 cells via E-cadherin downregulation and upregulation of N-cadherin and vimentin as well as increases in β-catenin nucleus translocation. Furthermore, XCL1 enhanced the expression of hypoxia-inducible factor-1α (HIF-1α) and phosphorylation of extracellular signal-regulated kinase (ERK) 1/2. Notably, the effects of XCL1 on cell migration and intracellular signaling were negated by knockdown of XCR1 using siRNA, confirming XCR1-mediated actions. Treating MDA-MB-231 cells with U0126, a specific mitogen-activated protein kinase kinase (MEK) 1/2 inhibitor, blocked XCL1-induced HIF-1α accumulation and cell migration. The effect of XCL1 on cell migration was also evaluated in ER-/HER2+ SK-BR-3 cells. XCL1 also promoted cell migration, EMT induction, HIF-1α accumulation, and ERK phosphorylation in SK-BR-3 cells. While XCL1 did not exhibit any significant impact on the matrix metalloproteinase (MMP)-2 and -9 expressions in MDA-MB-231 cells, it increased the expression of these enzymes in SK-BR-3 cells. Collectively, our results demonstrate that activation of the ERK/HIF-1α/EMT pathway is involved in the XCL1-induced migration of both MDA-MB-231 and SK-BR-3 breast cancer cells. Based on our findings, the XCL1–XCR1 interaction and its associated signaling molecules may serve as specific targets for the prevention of breast cancer cell migration and metastasis.

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Learning deep features for dead and living breast cancer cell classification without staining

Scientific Reports ◽

10.1038/s41598-021-89895-w ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Gisela Pattarone ◽

Laura Acion ◽

Marina Simian ◽

Emmanuel Iarussi

Keyword(s):

Breast Cancer ◽

Machine Learning ◽

Drug Treatment ◽

Cancer Cells ◽

Cancer Cell ◽

Breast Cancer Cell ◽

Cancer Biology ◽

Breast Cancer Cells ◽

Bright Field ◽

Cell Classification

AbstractAutomated cell classification in cancer biology is a challenging topic in computer vision and machine learning research. Breast cancer is the most common malignancy in women that usually involves phenotypically diverse populations of breast cancer cells and an heterogeneous stroma. In recent years, automated microscopy technologies are allowing the study of live cells over extended periods of time, simplifying the task of compiling large image databases. For instance, there have been several studies oriented towards building machine learning systems capable of automatically classifying images of different cell types (i.e. motor neurons, stem cells). In this work we were interested in classifying breast cancer cells as live or dead, based on a set of automatically retrieved morphological characteristics using image processing techniques. Our hypothesis is that live-dead classification can be performed without any staining and using only bright-field images as input. We tackled this problem using the JIMT-1 breast cancer cell line that grows as an adherent monolayer. First, a vast image set composed by JIMT-1 human breast cancer cells that had been exposed to a chemotherapeutic drug treatment (doxorubicin and paclitaxel) or vehicle control was compiled. Next, several classifiers were trained based on well-known convolutional neural networks (CNN) backbones to perform supervised classification using labels obtained from fluorescence microscopy images associated with each bright-field image. Model performances were evaluated and compared on a large number of bright-field images. The best model reached an AUC = 0.941 for classifying breast cancer cells without treatment. Furthermore, it reached AUC = 0.978 when classifying breast cancer cells under drug treatment. Our results highlight the potential of machine learning and computational image analysis to build new diagnosis tools that benefit the biomedical field by reducing cost, time, and stimulating work reproducibility. More importantly, we analyzed the way our classifiers clusterize bright-field images in the learned high-dimensional embedding and linked these groups to salient visual characteristics in live-dead cell biology observed by trained experts.

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