The role of HER2 and HER3 in HER2-amplified cancers beyond breast cancers

AbstractHER2 and HER3 play key driving functions in the pathophysiology of HER2-amplified breast cancers, but this function is less well characterized in other cancers driven by HER2 amplification. This study aimed to explore the role of HER2 and HER3 signaling in other types of HER2-amplified cancer. The expression and signaling activity of HER2, HER3, and downstream pathway proteins were studied in cell panels representing HER2-amplified cancers of the breast, bladder, colon and rectal, stomach, esophagus, lung, tongue, and endometrium along with controls lacking HER2 amplification. We report that HER2-amplified cancers are addicted to HER2 across different cancer types and the depth of addiction is best linked with the expression level of HER2, but not with HER3 expression. We report that the expression and constitutive phosphorylation of HER3 are ubiquitous in HER2-amplified breast cancer cell lines, but much more variable in HER2-amplified cancer cells from other tissues. We observed the lapatinib-induced compensatory upregulation of HER3 signaling in many types of HER2-amplified cancers, although with much variability. We find that HER3 expression is essential for in vivo tumorigenic growth in some HER2-amplified tumors but not others. Importantly HER3 expression level does not correlate well with its functional importance. More biomarkers will be needed to guide the optimal use of HER3 inhibitors in HER2-amplified cancers from non-breast origin. Unlike oncogenes activated through mutational events, the activation of HER2 through overexpression represents a gradient of activities and depth of addiction and the response to inhibitors follows a similar gradient.

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LPTO-06. A NOVEL BRAIN-PERMEANT CHEMOTHERAPEUTIC AGENT FOR THE TREATMENT OF BREAST CANCER LEPTOMENINGEAL METASTASIS

Neuro-Oncology Advances ◽

10.1093/noajnl/vdz014.029 ◽

2019 ◽

Vol 1 (Supplement_1) ◽

pp. i7-i7

Author(s):

Jiaojiao Deng ◽

Sophia Chernikova ◽

Wolf-Nicolas Fischer ◽

Kerry Koller ◽

Bernd Jandeleit ◽

...

Keyword(s):

Breast Cancer ◽

Brain Tumors ◽

Cell Lines ◽

Chemotherapeutic Agent ◽

Leptomeningeal Metastasis ◽

Breast Cancer Cell Lines ◽

Normal Brain ◽

Breast Cancers

Abstract Leptomeningeal metastasis (LM), a spread of cancer to the cerebrospinal fluid and meninges, is universally and rapidly fatal due to poor detection and no effective treatment. Breast cancers account for a majority of LMs from solid tumors, with triple-negative breast cancers (TNBCs) having the highest propensity to metastasize to LM. The treatment of LM is challenged by poor drug penetration into CNS and high neurotoxicity. Therefore, there is an urgent need for new modalities and targeted therapies able to overcome the limitations of current treatment options. Quadriga has discovered a novel, brain-permeant chemotherapeutic agent that is currently in development as a potential treatment for glioblastoma (GBM). The compound is active in suppressing the growth of GBM tumor cell lines implanted into the brain. Radiolabel distribution studies have shown significant tumor accumulation in intracranial brain tumors while sparing the adjacent normal brain tissue. Recently, we have demonstrated dose-dependent in vitro and in vivo anti-tumor activity with various breast cancer cell lines including the human TNBC cell line MDA-MB-231. To evaluate the in vivo antitumor activity of the compound on LM, we used the mouse model of LM based on the internal carotid injection of luciferase-expressing MDA-MB-231-BR3 cells. Once the bioluminescence signal intensity from the metastatic spread reached (0.2 - 0.5) x 106 photons/sec, mice were dosed i.p. twice a week with either 4 or 8 mg/kg for nine weeks. Tumor growth was monitored by bioluminescence. The compound was well tolerated and caused a significant delay in metastatic growth resulting in significant extension of survival. Tumors regressed completely in ~ 28 % of treated animals. Given that current treatments for LM are palliative with only few studies reporting a survival benefit, Quadriga’s new agent could be effective as a therapeutic for both primary and metastatic brain tumors such as LM. REF: https://onlinelibrary.wiley.com/doi/full/10.1002/pro6.43

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MRCKα Is Dispensable for Breast Cancer Development in the MMTV-PyMT Model

Cells ◽

10.3390/cells10040942 ◽

2021 ◽

Vol 10 (4) ◽

pp. 942

Author(s):

Mei Qi Kwa ◽

Rafael Brandao ◽

Trong H. Phung ◽

Jianfeng Ge ◽

Giuseppe Scieri ◽

...

Keyword(s):

Breast Cancer ◽

Gene Expression Signature ◽

Genomic Analysis ◽

Cancer Development ◽

Breast Cancer Cell Lines ◽

Normal Mammary Gland ◽

Breast Cancers ◽

Human Breast ◽

Breast Cancer Development

MRCKα is a ubiquitously expressed serine/threonine kinase involved in cell contraction and F-actin turnover, which is highly amplified in human breast cancer and part of a gene expression signature for bad prognosis. Nothing is known about the in vivo function of MRCKα. To explore MRCKα function in development and in breast cancer, we generated mice lacking a functional MRCKα gene. Mice were born close to the Mendelian ratio and showed no obvious phenotype including a normal mammary gland formation. Assessing breast cancer development using the transgenic MMTV-PyMT mouse model, loss of MRCKα did not affect tumor onset, tumor growth and metastasis formation. Deleting MRCKα and its related family member MRCKβ in two triple-negative breast cancer cell lines resulted in reduced invasion of MDA-MB-231 cells, but did not affect migration of 4T1 cells. Further genomic analysis of human breast cancers revealed that MRCKα is frequently co-amplified with the oncogenes ARID4B and AKT3 which might contribute to the prognostic value of MRCKα expression. Collectively, these data suggest that MRCKα might be a prognostic marker for breast cancer, but probably of limited functional importance.

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Role of the NUDT Enzymes in Breast Cancer

International Journal of Molecular Sciences ◽

10.3390/ijms22052267 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2267

Author(s):

Roni H. G. Wright ◽

Miguel Beato

Keyword(s):

Breast Cancer ◽

Signaling Pathways ◽

Cancer Progression ◽

Breast Cancers ◽

Metastatic Colonization ◽

Hormone Receptor Positive ◽

Aggressive Cancer ◽

Cancer Types ◽

Metastatic Process

Despite global research efforts, breast cancer remains the leading cause of cancer death in women worldwide. The majority of these deaths are due to metastasis occurring years after the initial treatment of the primary tumor and occurs at a higher frequency in hormone receptor-positive (Estrogen and Progesterone; HR+) breast cancers. We have previously described the role of NUDT5 (Nudix-linked to moiety X-5) in HR+ breast cancer progression, specifically with regards to the growth of breast cancer stem cells (BCSCs). BCSCs are known to be the initiators of epithelial-to-mesenchyme transition (EMT), metastatic colonization, and growth. Therefore, a greater understanding of the proteins and signaling pathways involved in the metastatic process may open the door for therapeutic opportunities. In this review, we discuss the role of NUDT5 and other members of the NUDT family of enzymes in breast and other cancer types. We highlight the use of global omics data based on our recent phosphoproteomic analysis of progestin signaling pathways in breast cancer cells and how this experimental approach provides insight into novel crosstalk mechanisms for stratification and drug discovery projects aiming to treat patients with aggressive cancer.

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Loss of an Estrogen Receptor Isoform (ERαΔ3) in Breast Cancer and the Consequences of Its Reexpression: Interference with Estrogen-Stimulated Properties of Malignant Transformation

Molecular Endocrinology ◽

10.1210/mend.11.13.0031 ◽

1997 ◽

Vol 11 (13) ◽

pp. 2004-2015 ◽

Cited By ~ 1

Author(s):

I. Erenburg ◽

B. Schachter ◽

R. Mira y Lopez ◽

L. Ossowski

Keyword(s):

Breast Cancer ◽

Estrogen Receptor ◽

Vector Control ◽

Cancer Cells ◽

Dominant Negative ◽

Breast Cancer Cell Lines ◽

Breast Cancers ◽

Normal Breast Epithelium ◽

Anchorage Independent Growth

Abstract Comparison of mRNA ratios of a non-DNA-binding estrogen receptor (ERα) isoform, missing exon 3 (ERαΔ3), to the full-length ERα, in normal breast epithelium to that in primary breast cancers and breast cancer cell lines revealed a 30-fold reduction of this ratio in cancer cells (P < 0.0001). To test what functions may have been affected by the loss of ERαΔ3, stable clones of MCF-7 cells expressing ectopic ERαΔ3 protein, at the range of physiological ERα, were generated. In vector-transfected controls the ERαΔ3-mRNA and protein were less than 10% while in the ERαΔ3-expressing clones, ERαΔ3-mRNA and protein ranged from 36–76% of the total ERα. Estrogen (E2) stimulated the expression of pS2-mRNA in pMV7 vector control cells, but the stimulation was reduced by up to 93% in ERαΔ3-expressing clones. In addition, several properties associated with the transformed phenotype were also strongly affected when ERαΔ3 protein was reexpressed. Compared with vector-transfected control cells, the saturation density of the ERαΔ3-expressing clones was reduced by 50–68%, while their exponential growth rate was only slightly (14.5 ± 5%) lower. The in vivo invasiveness of the ERαΔ3-expressing cells was significantly reduced (P = 0.007) by up to 79%. E2 stimulated anchorage-independent growth of the pMV7 vector control cells, but reduced it to below baseline levels in ERαΔ3 clones. The reduction of the pS2 response to E2 in the ERαΔ3-expressing clones and the E2 block of anchorage-independent growth to below baseline were more pronounced than expected from the dominant negative function of ERαΔ3. These observations suggest that E2 may activate an additional ERαΔ3-dependent inhibitory pathway. The drastic reduction of ERαΔ3 to ERα ratio in breast cancer, and the fact that when present in breast cancer cells this isoform leads to a suppression, rather than enhancement, of the transformed phenotype by E2 suggests that the regulation of ERα-mRNA splicing may need to be altered for the breast carcinogenesis to proceed.

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Expression of MALAT1 Promotes Trastuzumab Resistance in HER2 Overexpressing Breast Cancers

Cancers ◽

10.3390/cancers12071918 ◽

2020 ◽

Vol 12 (7) ◽

pp. 1918

Author(s):

Yanyuan Wu ◽

Marianna Sarkissyan ◽

Ochanya Ogah ◽

Juri Kim ◽

Jaydutt V. Vadgama

Keyword(s):

Breast Cancer ◽

Cancer Progression ◽

Akt Pathway ◽

Breast Cancers ◽

Trastuzumab Resistance ◽

Mesenchymal Transition ◽

Cancer Tissues

Background: Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is associated with cancer progression. Our study examined the role of MALAT1 in breast cancer and the mechanisms involved in the regulation of MALAT1. Methods: In vitro cell and in vivo animal models were used to examine the role of MALAT1 in breast cancer. The interaction of FOXO1 (Forkhead Box O1) at the promoter region of MALAT1 was investigated by chromatin immunoprecipitation (ChIP) assay. Results: The data shows an elevated expression of MALAT1 in breast cancer tissues and cells compared to non-cancer tissues and cells. The highest level of MALAT1 was observed in metastatic triple-negative breast cancer and trastuzumab-resistant HER2 (human epidermal growth factor receptor 2) overexpressing (HER2+) cells. Knockdown of MALAT1 in trastuzumab-resistant HER2+ cells reversed epithelial to mesenchymal transition-like phenotype and cell invasiveness. It improved the sensitivity of the cell’s response to trastuzumab. Furthermore, activation of Akt by phosphorylation was associated with the upregulation of MALAT1. The transcription factor FOXO1 regulates the expression of MALAT1 via the PI3/Akt pathway. Conclusions: We show that MALAT1 contributes to HER2+ cell resistance to trastuzumab. Targeting the PI3/Akt pathway and stabilizing FOXO1 translocation could inhibit the upregulation of MALAT1.

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New generation breast cancer cell lines developed from patient-derived xenografts

Breast Cancer Research ◽

10.1186/s13058-020-01300-y ◽

2020 ◽

Vol 22 (1) ◽

Author(s):

Jessica Finlay-Schultz ◽

Britta M. Jacobsen ◽

Duncan Riley ◽

Kiran V. Paul ◽

Scott Turner ◽

...

Keyword(s):

Breast Cancer ◽

Cell Lines ◽

Cancer Cell ◽

Breast Cancer Cell ◽

Cancer Cell Lines ◽

Breast Cancer Cell Lines ◽

Breast Cancers ◽

Luminal A ◽

New Generation

Abstract Background Breast cancer is a highly heterogeneous disease characterized by multiple histologic and molecular subtypes. While a myriad of breast cancer cell lines have been developed over the past 60 years, estrogen receptor alpha (ER)+ disease and some mutations associated with this subtype remain underrepresented. Here we describe six breast cancer cell lines derived from patient-derived xenografts (PDX) and their general characteristics. Methods Established breast cancer PDX were processed into cell suspensions and placed into standard 2D cell culture; six emerged into long-term passageable cell lines. Cell lines were assessed for protein expression of common luminal, basal, and mesenchymal markers, growth assessed in response to estrogens and endocrine therapies, and RNA-seq and oncogenomics testing performed to compare relative transcript levels and identify putative oncogenic drivers. Results Three cell lines express ER and two are also progesterone receptor (PR) positive; PAM50 subtyping identified one line as luminal A. One of the ER+PR+ lines harbors a D538G mutation in the gene for ER (ESR1), providing a natural model that contains this endocrine-resistant genotype. The third ER+PR−/low cell line has mucinous features, a rare histologic type of breast cancer. The three other lines are ER− and represent two basal-like and a mixed ductal/lobular breast cancer. The cell lines show varied responses to tamoxifen and fulvestrant, and three were demonstrated to regrow tumors in vivo. RNA sequencing confirms all cell lines are human and epithelial. Targeted oncogenomics testing confirmed the noted ESR1 mutation in addition to other mutations (i.e., PIK3CA, BRCA2, CCND1, NF1, TP53, MYC) and amplifications (i.e., FGFR1, FGFR3) frequently found in breast cancers. Conclusions These new generation breast cancer cell lines add to the existing repository of breast cancer models, increase the number of ER+ lines, and provide a resource that can be genetically modified for studying several important clinical breast cancer features.

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Kinome rewiring reveals AURKA is a molecular barrier to the efficacy of PI3K/mTOR-pathway inhibitors in breast cancer

10.1101/158295 ◽

2017 ◽

Author(s):

Hayley J Donnella ◽

James T Webber ◽

Rebecca S Levin ◽

Roman Camarda ◽

Olga Momcilovic ◽

...

Keyword(s):

Breast Cancer ◽

Tumor Regression ◽

Target Therapy ◽

Mtor Pathway ◽

Mtor Signaling ◽

Breast Cancer Cell Lines ◽

Full Potential ◽

Breast Cancers ◽

Dynamic Changes

ABSTRACTDysregulation of the PI3K-AKT-mTOR signaling network is a prominent feature of breast cancers. However, clinical responses to drugs targeting this pathway have been modest. We hypothesized that dynamic changes in signaling, including adaptation and feedback, limit drug efficacy. Using a quantitative chemoproteomics approach we mapped dynamic changes in the kinome in response to various agents and identified signaling changes that correlate with drug sensitivity. Measurement of dynamics across a panel of breast cancer cell lines identified that maintenance of CDK4 and AURKA activity was associated with drug resistance. We tested whether incomplete inhibition of CDK4 or AURKA was a source of therapy failure and found that inhibition of either was sufficient to sensitize most breast cancer cells to PI3K, AKT, and mTOR inhibitors. In particular, drug combinations including the AURKA inhibitor MLN8237 were highly synergistic and induced apoptosis through enhanced suppression of mTOR signaling to S6 and 4E-BP1 leading to tumor regressionin vivo.This signaling map identifies survival factors whose presence limits the efficacy of target therapy and indicates that Aurora kinase co-inhibition could unlock the full potential of PI3K-AKT-mTOR pathway inhibitors in breast cancer.

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The Induction of Apoptosis by Resveratrol Through Regulatory Effect of miR-21 on the Gene Expression of Bcl2 and Bax in HCT-116 Cells

Avicenna Journal of Medical Biochemistry ◽

10.34172/ajmb.2019.05 ◽

2019 ◽

Vol 7 (1) ◽

pp. 21-27

Author(s):

Nooshin Shabab ◽

Saeid Afshar ◽

Massoud Saidijam

Keyword(s):

Gene Expression ◽

Vital Role ◽

Expression Level ◽

Apoptosis Pathway ◽

Treatment Agent ◽

Hct 116 ◽

Pcr Method ◽

Hct 116 Cells

Background: Resveratrol (RezV) which is found in several plants including grapes and types of berries has a vital role in inducing apoptosis and suppressing cell proliferation. Although the role of Bcl-2 in the apoptosis has been known in several pathways, the role and mechanism of miR-21 in the regulation of apoptosis in colorectal cancer (CRC) cells are unclear. Objectives: The main aim of this study was to evaluate the effects of RezV on the expression level of miR-21, Bax, and Bcl2 in colorectal tumor cells. Methods: In this study, the effect of RezV on the viability of CRC cells was evaluated by MTT assay. Then, the expression level of miR-21 was evaluated by real-time polymerase chain reaction (PCR) method. For evaluating HCT-116 cells apoptosis, the expression level of Bax and Bcl2 that are involved in the apoptosis pathway was investigated by the same method. Results: RezV inhibits the viability of HCT-116 cells. MiR-21 gene expression was decreased after 24 hours of treatment with RezV. The reduction of miR-21 expression leads to the reduction of the Bcl2 gene expression level. Moreover, increasing the Bax/Bcl2 ratio enhances HCT-116 cells apoptosis. Conclusion: In summary, RezV might be used as a co-treatment agent for CRC. On the other hand, conducting the in vivo study to evaluate the effects of RezV was critical.

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DDIS-31. A NOVEL BRAIN-PERMEANT CHEMOTHERAPEUTIC AGENT FOR THE TREATMENT OF BREAST CANCER LEPTOMENINGEAL METASTASIS

Neuro-Oncology ◽

10.1093/neuonc/noz175.282 ◽

2019 ◽

Vol 21 (Supplement_6) ◽

pp. vi70-vi70

Author(s):

Jiaojiao Deng ◽

Sophia Chernikova ◽

Wolf-Nicolas Fischer ◽

Kerry Koller ◽

Bernd Jandeleit ◽

...

Keyword(s):

Breast Cancer ◽

Chemotherapeutic Agent ◽

Treatment Options ◽

Leptomeningeal Metastasis ◽

Current Treatment ◽

Breast Cancer Cell Lines ◽

Breast Cancers ◽

Tnbc Cell Line

Abstract Leptomeningeal metastasis (LM), a spread of cancer to the cerebrospinal fluid and meninges, is universally and rapidly fatal due to poor detection and no effective treatment. Breast cancers account for a majority of LMs from solid tumors, with triple-negative breast cancers (TNBCs) having the highest propensity to metastasize to LM. The treatment of LM is challenged by poor drug penetration into CNS and high neurotoxicity. Therefore, there is an urgent need for new modalities and targeted therapies able to overcome the limitations of current treatment options. Quadriga has discovered a novel, brain-permeant chemotherapeutic agent that is currently in development as a potential treatment for glioblastoma (GBM). Recently, we have demonstrated dose-dependent in vitro and in vivo anti-tumor activity with various breast cancer cell lines including the human TNBC cell line MDA-MB-231. To evaluate the in vivo antitumor activity of the compound on LM, we used the mouse model of LM based on the internal carotid injection of luciferase-expressing MDA-MB-231-BR3 cells. Once the bioluminescence signal intensity from the metastatic spread reached (0.2 - 0.5) x 106photons/sec, mice were dosed i.v. (8 mg/kg once a week for nine weeks) or i.p. (4 or 8 mg/kg twice a week for nine weeks). Tumor growth was monitored by bioluminescence. The compound was well tolerated and caused a significant delay in metastatic growth resulting in significant extension of survival. Tumors regressed completely in ~ 28 % of treated animals in the i.p. group. Given that current treatments for LM are palliative with only few studies reporting a survival benefit, Quadriga’s new agent could be effective as a therapeutic for both primary and metastatic brain tumors such as LM. REF: https://onlinelibrary.wiley.com/doi/full/10.1002/pro6.43

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Integrated Metabolic Profiling and Gene Expression Analysis Reveals Therapeutic Modalities in Breast Cancer

10.21203/rs.3.rs-117384/v1 ◽

2020 ◽

Author(s):

Chengheng Liao ◽

Cherise Ryan Glodowski ◽

Cheng Fan ◽

Juan Liu ◽

Kevin Raynard Mott ◽

...

Keyword(s):

Breast Cancer ◽

Gene Expression ◽

Cell Lines ◽

Metabolic Profiling ◽

Breast Cancer Cell Lines ◽

Breast Cancers ◽

Arginine Biosynthesis ◽

Metabolic Dysregulation

Abstract Metabolic dysregulation is one of the distinctive features in breast cancer. However, examining the metabolic features in various subtypes of breast cancer in their relationship to gene expression features in a physiologically relevant setting remains understudied. By performing metabolic profiling on triple-negative breast cancer (TNBC) and ER+ breast cancers from patients, TNBC patient-derived xenografts (PDXs), and representative breast cancer cell lines grown as tumors in vivo, we identify two distinctive groups defined by metabolites; a “Nucleotide-Enriched” group that shows high levels of pyrimidine pathway metabolites and biosynthetic enzymes, and a “Arginine Biosynthesis-Enriched” group that shows high levels of arginine biosynthesis intermediates. We reveal different metabolic enrichment profiles between cell lines grown in vitro versus in vivo, where cell lines grown in vivo more faithfually recapitulate patient tumors metabolic profiles. In addition, with integrated metabolic and gene expression profiling we identify a subset of genes that strongly correlates with the Nucleotide-Enriched metabolic profile, and which strongly predicts patient prognosis. As a proof-of-principle, when we target Nucleotide-Enriched metabolic dysregulation with a pyrimidine biosynthesis inhibitor (Brequinar), and/or a glutaminase inhibitor (CB-839), we observe therapeutic efficacy and decreased tumor growth in representative TNBC cell lines and an in vivo PDX upon combinatorial drug treatment. Our study reveals new therapeutic opportunities in breast cancer guided by a genomic biomarker, which could prove highly impactful for rapidly proliferating breast cancers specifically.

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