Transcriptome analysis of heterogeneity in mouse model of metastatic breast cancer

Abstract Background Cancer metastasis is a complex process involving the spread of malignant cells from a primary tumor to distal organs. Understanding this cascade at a mechanistic level could provide critical new insights into the disease and potentially reveal new avenues for treatment. Transcriptome profiling of spontaneous cancer models is an attractive method to examine the dynamic changes accompanying tumor cell spread. However, such studies are complicated by the underlying heterogeneity of the cell types involved. The purpose of this study was to examine the transcriptomes of metastatic breast cancer cells using the well-established MMTV-PyMT mouse model. Methods Organ-derived metastatic cell lines were harvested from 10 female MMTV-PyMT mice. Cancer cells were isolated and sorted based on the expression of CD44low/EpCAMhigh or CD44high/EpCAMhigh surface markers. RNA from each cell line was extracted and sequenced using the NextSeq 500 Illumina platform. Tissue-specific genes were compared across the different metastatic and primary tumor samples. Reads were mapped to the mouse genome using STAR, and gene expression was quantified using RSEM. Single-cell RNA-seq (scRNA-seq) was performed on select samples using the ddSeq platform by BioRad and analyzed using Seurat v3.2.3. Monocle2 was used to infer pseudo-time progression. Results Comparison of RNA sequencing data across all cell populations produced distinct gene clusters. Differential gene expression patterns related to CD44 expression, organ tropism, and immunomodulatory signatures were observed. scRNA-seq identified expression profiles based on tissue-dependent niches and clonal heterogeneity. These cohorts of data were narrowed down to identify subsets of genes with high expression and known metastatic propensity. Dot plot analyses further revealed clusters expressing cancer stem cell and cancer dormancy markers. Changes in relevant genes were investigated across pseudo-time and tissue origin using Monocle2. These data revealed transcriptomes that may contribute to sub-clonal evolution and treatment evasion during cancer progression. Conclusions We performed a comprehensive transcriptome analysis of tumor heterogeneity and organ tropism during breast cancer metastasis. These data add to our understanding of metastatic progression and highlight targets for breast cancer treatment. These markers could also be used to image the impact of tumor heterogeneity on metastases.

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Nucleotide de novo synthesis increases breast cancer stemness and metastasis via cGMP-PKG-MAPK signaling pathway

PLoS Biology ◽

10.1371/journal.pbio.3000872 ◽

2020 ◽

Vol 18 (11) ◽

pp. e3000872

Author(s):

Yajing Lv ◽

Xiaoshuang Wang ◽

Xiaoyu Li ◽

Guangwei Xu ◽

Yuting Bai ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Cancer Cells ◽

Signaling Pathway ◽

Breast Cancer Cells ◽

Cancer Metastasis ◽

De Novo ◽

Metastatic Breast ◽

Metabolic Reprogramming ◽

De Novo Synthesis

Metabolic reprogramming to fulfill the biosynthetic and bioenergetic demands of cancer cells has aroused great interest in recent years. However, metabolic reprogramming for cancer metastasis has not been well elucidated. Here, we screened a subpopulation of breast cancer cells with highly metastatic capacity to the lung in mice and investigated the metabolic alternations by analyzing the metabolome and the transcriptome, which were confirmed in breast cancer cells, mouse models, and patients’ tissues. The effects and the mechanisms of nucleotide de novo synthesis in cancer metastasis were further evaluated in vitro and in vivo. In our study, we report an increased nucleotide de novo synthesis as a key metabolic hallmark in metastatic breast cancer cells and revealed that enforced nucleotide de novo synthesis was enough to drive the metastasis of breast cancer cells. An increased key metabolite of de novo synthesis, guanosine-5'-triphosphate (GTP), is able to generate more cyclic guanosine monophosphate (cGMP) to activate cGMP-dependent protein kinases PKG and downstream MAPK pathway, resulting in the increased tumor cell stemness and metastasis. Blocking de novo synthesis by silencing phosphoribosylpyrophosphate synthetase 2 (PRPS2) can effectively decrease the stemness of breast cancer cells and reduce the lung metastasis. More interestingly, in breast cancer patients, the level of plasma uric acid (UA), a downstream metabolite of purine, is tightly correlated with patient’s survival. Our study uncovered that increased de novo synthesis is a metabolic hallmark of metastatic breast cancer cells and its metabolites can regulate the signaling pathway to promote the stemness and metastasis of breast cancer.

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Metastatic Breast Cancer, Organotropism and Therapeutics: A Review

Current Cancer Drug Targets ◽

10.2174/1568009621666210806094410 ◽

2021 ◽

Vol 21 ◽

Author(s):

Ajaz Ahmad Waza ◽

Najeebul Tarfeen ◽

Sabhiya Majid ◽

Yasmeena Hassan ◽

Rashid Mir ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Cancer Metastasis ◽

Metastatic Breast ◽

Breast Cancer Metastasis ◽

Breast Cancer Metastases ◽

Cancer Metastases ◽

Main Culprit

: The final stage of breast cancer involves spreading breast cancer cells to the vital organs like the brain, liver lungs and bones in the process called metastasis. Once the target organ is overtaken by the metastatic breast cancer cells, its usual function is compromised causing organ dysfunction and death. Despite the significant research on breast cancer metastasis, it’s still the main culprit of breast cancer-related deaths. Exploring the complex molecular pathways associated with the initiation and progression of breast cancer metastasis could lead to the discovery of more effective ways of treating the devastating phenomenon. The present review article highlights the recent advances to understand the complexity associated with breast cancer metastases, organotropism and therapeutic advances.

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Transcriptome analysis reveals an osteomimetic phenotype for human bone metastatic breast cancer cells

European Journal of Cancer Supplements ◽

10.1016/s1359-6349(06)80413-1 ◽

2006 ◽

Vol 4 (2) ◽

pp. 163 ◽

Cited By ~ 1

Author(s):

A. Bellahcene ◽

Bachelier ◽

C. Detry ◽

R. Lidereau ◽

P. Clezardin ◽

...

Keyword(s):

Breast Cancer ◽

Metastatic Breast Cancer ◽

Cancer Cells ◽

Transcriptome Analysis ◽

Breast Cancer Cells ◽

Metastatic Breast ◽

Human Bone

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Matrix Rigidity Induces Osteolytic Gene Expression of Metastatic Breast Cancer Cells

PLoS ONE ◽

10.1371/journal.pone.0015451 ◽

2010 ◽

Vol 5 (11) ◽

pp. e15451 ◽

Cited By ~ 59

Author(s):

Nazanin S. Ruppender ◽

Alyssa R. Merkel ◽

T. John Martin ◽

Gregory R. Mundy ◽

Julie A. Sterling ◽

...

Keyword(s):

Breast Cancer ◽

Gene Expression ◽

Metastatic Breast Cancer ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Metastatic Breast ◽

Matrix Rigidity

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BSCI-01. ACTIVATION OF c-Met/β1-INTEGRIN COMPLEX RESULTS IN INCREASE OF MESENCHYMAL GENE EXPRESSION AND STEM CELL POPULATION IN METASTATIC BREAST CANCER TO THE BRAIN AND SPINE

Neuro-Oncology Advances ◽

10.1093/noajnl/vdz014.000 ◽

2019 ◽

Vol 1 (Supplement_1) ◽

pp. i1-i1

Author(s):

Darryl Lau ◽

Harsh Wadhwa ◽

Alan Nguyen ◽

Ankush Chandra ◽

Manish Aghi

Keyword(s):

Breast Cancer ◽

Gene Expression ◽

Metastatic Breast Cancer ◽

Complex Formation ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Metastatic Breast ◽

Stem Cell Population ◽

Β1 Integrin ◽

The Brain

Abstract INTRODUCTION: C-met and β-integrins play a central role in nearly all stages of cancer metastasis. They bind at the cell surface, driving ligand independent co-activation of downstream pathways. Greater complex is seen in metastatic tumors vs. its primary tumor counterparts in patients. The molecular, cellular, and clinical effects of complex formation in metastatic breast cancer are investigated. METHODS: Utilizing variations of the MDA-231 breast cancer cell lines (standard MDA-231, inducible complex formation MDA-231, brain seeking MDA 231, lung seeking MDA 231, and bone seeking MDA-231), in vitro and in vivo studies were performed. Clinical correlates from patient samples were studied. RESULTS: Induction of c-Met/β1 complex promotes breast cancer invasion (p< 0.001), migration (p< 0.05), circulation intravasation (p< 0.01), and adhesion (p< 0.01). These effects may be driven by the increased mesenchymal character (p< 0.05) and larger stem cell population (p< 0.001) caused by inducing c-Met/β1 complex formation. OS2966 (a therapeutic β1 integrin blocking antibody) decreases invasion (p< 0.05), intravasation (p< 0.05), and mesenchymal form factor (p< 0.001) and gene expression (p< 0.001) in MDA-MB-231 cells. Brain- and bone-seeking breast cancer cells have higher c-Met/β1 complex than parental controls and preferentially adhere to tissue-specific matrix (p< 0.01). In intracardiac metastasis models, complex formation resulted in significantly higher metastatic burden and shorter survival times (p< 0.001). qPCR data suggests that complex formation may drive exiting and colonization of cancer cells (micrometastasis) rather than tumor growth. Patient brain and bone metastases demonstrated high β1/c-Met levels. CONCLUSIONS: The c-Met/β1 complex drives intravasation and extravasation of breast cancer cells from the circulation. Preferential affinity for tissue-specific matrix enables the c-Met/β1 complex to drive formation of breast cancer metastases to the brain and bone. Pharmacological and genetic targeting of the complex with agents may provide therapeutic approaches to prevent metastases, particularly to the brain and bone.

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