Metastatic Potential Of Breast Cancer Research Articles

IGFBP6 Modulates Proteostasis by Activating ATF4 Targets and Reducing ER Retrotranslocon Expression.

Reduced expression of the IGFBP6 protein leads to an increase in the metastatic potential of breast cancer (BC) cells. The level of protein synthesis in tumor cells is increased, leading to a compensatory adjustment of proteostasis. One of the tools used to study proteostasis is protein toxins of the RIP-II family, which irreversibly inactivate ribosomes (particularly, viscumin). We investigated the effect of IGFBP6 gene knockdown on the proteostasis in the BC cell line MDA-MB-231. Ribosomes from MDA-MB-231IGFBP6 cells, knockdown for the IGFBP6 gene, are less efficiently modified by the toxin. This is probably due to the reduced transport of the viscumin catalytic subunit from the ER to the cytoplasm. MDA-MB-231IGFBP6 cells showed reduced expression of the retrotranslocon HRD1/Derlin subunit, which is a component of the ER-associated protein degradation system (ERAD). For ATF4 transcription factor, which is a part of the ER unfolded protein response (UPR) pathway, an increased expression of its targets was found.

Monitoring of Nanodrug Accumulation in Murine Breast Cancer Metastases.

Metastatic breast cancer is a devastating disease with very limited therapeutic options, calling for new therapeutic strategies. Oncogenic miRNAs have been shown to be associated with the metastatic potential of breast cancer and are implicated in tumor cell migration, invasion, and viability. However, it can be difficult to deliver an inhibitory RNA molecule to the tissue of interest. To overcome this challenge and deliver active antisense oligonucleotides to tumors, we utilized magnetic iron oxide nanoparticles as a delivery platform. These nanoparticles target tissues with increased vascular permeability, such as sites of inflammation or cancer. Delivery of these nanoparticles can be monitored in vivo by magnetic resonance imaging (MRI) due to their magnetic properties. Translation of this therapeutic approach into the clinic will be more accessible because of its compatibility with this relevant imaging modality. They can also be labeled with other imaging reporters such as a Cy5.5 near-infrared optical dye for correlative optical imaging and fluorescence microscopy. Here, we demonstrate that nanoparticles labeled with Cy5.5 and conjugated to therapeutic oligomers targeting oncogenic miRNA-10b (termed MN-anti-miR10b, or "nanodrug") administered intravenously accumulate in metastatic sites, opening a possibility for therapeutic intervention of metastatic breast cancer.

A tricky singular papular peri‐cicatricial mammarian lesion

AbstractBreast cancer represents the most common malignancy in women worldwide. In most cases, metastasis is the leading cause of mortality. Early diagnosis is still challenging despite standardised, government‐led screening programs, but is crucial in achieving improved survival rates. Additionally, a deeper understanding of the metastatic potential of breast cancer is critical for developing therapeutic interventions to combat widespread disease. Cutaneous metastasis from underlying breast carcinoma is uncommon as the first manifestation of visceral malignancies and is commonly observed in advanced‐stage malignancies, often associated with poor prognosis, and a prompt, precise tissue diagnosis is mandatory. A high index of suspicion in oncologic patients is required to diagnose these lesions, as they can mimic benign skin manifestations and clinical findings may be subtle and going unnoticed. We report on a case of a 76‐year‐old female patient presenting to our non‐invasive diagnostic outpatient clinic with an unusual cutaneous presentation, as an early sign of locally advanced invasive ductal carcinoma breast cancer recurrence. The aim of our article is to underline the importance of the dermatologist in the multi‐disciplinary oncologic diagnostic process, including non‐invasive imaging evaluation of cutaneous lesions, especially insidious breast carcinomas. Dynamic optical coherence tomography (D‐OCT) is not routinely used due to its cost, therefore lesion's aspect has not been completely described, consequently, the correct evaluation of skin architecture appearance can add important information, especially in cutaneous oncology where it can help in early diagnosis or cancer recurrency. OCT may contribute to the detection of subclinical cutaneous manifestations of cancer or recurrence, in particular, when they are difficult to differentiate clinically from benign lesion. In the case we described, OCT of suspected lesion showed the loss of the DEJ with solid nests and irregular vessels.

Abstract A037: Metabolic maneuvering of glycocalyx hypersialylation is a smart and healthy way of curbing metastatic potential in breast cancer

Abstract Metastatic breast cancer is currently the most deadly and incurable stage of breast cancer. A recent metabolic screen has identified sialic acid as a key player in progression of breast cancer metastasis. In the present study, we metabolically target the hypersialylation of metastatic breast cancer cells using appropriately designed nutritionary interventions. Our rationales are the following: (a) The aberrantly sialylated, hyperbranched glycocalyx promotes metastasis by facilitating cellular migration and immune evasion. (b) As hypersialylation relies heavily on enhanced sialic acid biosynthesis from the oncogenic glycolytic surge and preferential dietary uptake of glucose by cancer cells, it stands to reason that dietary changes can impact the extent of sialylation of the glycocalyx. Considering these points, we hypothesized that it was possible to control the degree of glycocalyx sialylation in breast cancer cells using an appropriate nutritionary regimen, which will in turn modulate the progression to invasive phenotype. The goal is to harness the metabolism of cancer cells themselves to curb their metastatic potential. Using a specific ketone-body forming metabolite called 3-hydroxybutyrate (HB) and lowering of glucose concentration, the cell culture medium was modified to mimic ketogenic diet. The response of metastatic breast cancer cells and normal breast epithelial cells was then monitored. The two main measures of cellular response were: cell surface sialylation via fluorescence microscopy and fluorescence lifetime imaging (FLIM) of intracellular NADH as a marker of metabolic index. We are currently investigating the consequences of nutritionary interventions on metastatic potential of breast cancer cells by measuring their impact on cellular proliferation, clonogenicity and migratory abilities. We have observed that the main metabolite of ketogenic diet, HB, tends to protect metastatic breast cancer cells from DOX treatment when supplemented in a low-glucose (LG) medium. However, the extent of increase in cell surface sialylation is very modest in comparison to that in normal breast epithelial cells. This differential increase in sialylation implies that a ketogenic diet might significantly promote the proliferation of healthy cells over the proliferation of metastatic breast cancer cells. FLIM measurements indicate that the chemotherapeutic, Doxorubicin tends to induce an initial preference for glycolysis in invasive breast cancer cells. While an HB rich LG media by itself promotes glycolysis in these cells, it suppresses any further Doxorubicin induced onset of glycolysis pointing to a protective mechanism against the chemotherapeutic. Through this ongoing study, we aim to decipher the right set of nutrients that would “deshield” the breast cancer cells and lower their metastatic disposition. The ultimate goal of our research is to determine a paradigm of drugs and diet that metastatic breast cancer cells are most responsive to, and that would translate into a viable remedy for metastatic breast cancer with minimal side-effects. Citation Format: Mohini Kamra, Yuan-I Chen, Paula C Delgado, Tim Yeh, Amy Brock, Sapun H Parekh. Metabolic maneuvering of glycocalyx hypersialylation is a smart and healthy way of curbing metastatic potential in breast cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr A037.

Effect of Paxillin Expression and Phosphorylation on Colorectal Cancer Prognosis and Metastasis.

Colorectal cancer (CRC) is the third most common cancer worldwide, and metastasis is strongly associated with poor prognosis in patients with CRC. We have previously found that the expression and phosphorylation of paxillin (PXN) play an important role in the metastatic potential of breast cancer. This study examined the potential role of PXN in CRC metastasis. Resected tumor specimens from 92 patients with CRC were subjected to immunohistochemical analysis of PXN levels. Three human CRC cell lines, HCT116, LoVo, and SW480 were used for scratch and transwell invasion assays to examine the effects of PXN over-expression. RNA sequencing was performed to obtain the expression profiles under PXN over-expression. High levels of PXN were significantly correlated with advanced stage, higher carcinoembryonic antigen and carbohydrate antigen 19-9 levels, and poorer overall survival. The migration ability of CRC cells was enhanced by exogenous PXN over-expression, but this enhancement was not observed in cells harboring exogenously mutated PXN at Tyr31 or Tyr88 phosphorylation sites. In PXN-over-expressing cells, TNF-α signaling via NF-[Formula: see text]B was positively enriched. PXN expression and phosphorylation at Tyr31 or Tyr88 may influence the migration and invasion of CRC cells. PXN expression and phosphorylation at Tyr31 or Tyr88 are promising targets for evaluating prognosis and treating CRC.

Transcriptome-based identification of key actin-binding proteins associated with high metastatic potential in breast cancer.

Actin-binding proteins (ABPs) are essential for the regulation of morphological plasticity required for tumor cells to metastasize. The aim of this study was to perform an unbiased bioinformatic approach to identify the key ABPs significantly associated with the metastatic potential of breast cancer cells. Microarray data from 181 primary breast cancer samples from our hospital were used, and all genes belonging to the Gene Ontology term actin cytoskeleton organization were obtained from QuickGO. Association with metastasis-free survival probability was tested using Cox proportional hazards regression, and pairwise co-expression was tested by Pearson correlations. Differential expression between different subgroups was analyzed using Wilcoxon tests for dichotomous traits and Kruskal-Wallis tests for categorical traits. Validation was performed using four publicly available breast cancer datasets. ARHGAP25 was significantly associated with a low metastatic potential, and CFL1, TMSB15A, and ACTL8 were significantly associated with a high metastatic potential. A significantly higher expression of CFL1, TMSB15A, and ACTL8 mRNA was found in the more aggressive Her2-positive and triple-negative subtypes as well as in ER-negative samples. Also, these genes were co-expressed in the same tumors. However, only mRNA levels of CFL1 were increased in pN1 compared to pN0 patients. External validation revealed that CFL1 and TMSB15A had significant associations with consistent hazard ratios in two breast cancer cohorts, and among these, CFL1 exhibited the highest hazard ratios. CFL1 showed the strongest correlation with the metastatic potential of breast tumors. Thus, targeted inhibition of CFL1 might be a promising approach to treat malignant breast cancer cells.

A Novel Algorithm for Evaluating Bone Metastatic Potential of Breast Cancer through Morphometry and Computational Mathematics

Bone metastases represent about 70% of breast cancer metastases and are associated with worse prognosis as the tumor cells acquire more aggressive features. The selection and investigation of patients with a high risk of developing bone metastasis would have a significant impact on patients’ management and survival. The patients were selected from the database of Carol Davila Clinical Nephrology Hospital of Bucharest. Their tumor specimens were pathologically processed, and a representative area was selected. This area was scanned using an Olympus VS200 slide scanner and further analyzed using QuPath software v0.4.4. A representative group of approximately 60–100 tumor cells was selected from each section, for which the following parameters were analyzed: nuclear area, nuclear perimeter, long axis and cell surface. Starting from these measurements, the following were calculated: the mean nuclear area and mean nuclear volume, the nucleus to cytoplasm ratio, the length of the two axes, the long axis to short axis ratio, the acyclicity and anellipticity grade and the mean internuclear distance. The tumor cells belonging to patients known to have bone metastasis seemed to have a lower nuclear area (<55 µm2, p = 0.0035), smaller long axis (<9 µm, p = 0.0015), smaller values for the small axis (<7 µm, p = 0.0008), smaller mean nuclear volume (<200 µm3, p = 0.0146) and lower mean internuclear distance (<10.5 µm, p = 0.0007) but a higher nucleus to cytoplasm ratio (>1.1, p = 0.0418), higher axis ratio (>1.2, p = 0.088), higher acyclicity grade (>1.145, p = 0.0857) and higher anellipticity grade (>1.14, p = 0.1362). These parameters can be used for the evaluation of risk category of developing bone metastases. These results can be useful for the evaluation of bone metastatic potential of breast cancer and for the selection of high-risk patients whose molecular profiles would require further investigations and evaluation.

Relationship Between Metabolic Activity, Cellularity, Histopathological Features of Primary Tumors and Distant Metastatic Potential in Breast Cancer.

The aim of this study was to evaluate the relationship between the types of distant metastatic spread, histopathological features, and imaging features of primary tumor on positron emission tomography/magnetic resonance imaging (PET/MRI) for primary staging in newly diagnosed breast invasive ductal carcinoma (IDC) patients. Data from 289 female patients were retrospectively evaluated. Maximum standardized uptake value, metabolic tumor volume (MTV), total lesion glycolysis (TLG), and minimum apparent diffusion coefficient (ADCmin) values of primary tumors were obtained from PET/MRI. The patients were grouped as non-metastatic, oligometastatic (1-5 metastatic lesions) and multimetastatic (>5 metastatic lesions) disease according to the number of distant metastases, and divided into two groups as isolated bone metastasis (IBM) and mixed/soft tissue metastasis (M-SM) groups according to the sites of metastatic spread. Metabolic parameters had higher values and ADCmin had lower values in the multimetastatic and oligometastatic groups than in the non-metastatic group. MTV was the only parameter that showed significant difference between the multimetastatic and oligometastatic groups. MTV and TLG were significantly higher in the M-SM group than in the IBM group. 18F-fluorodeoxyglucose PET parameters had significantly higher values in grade 3, hormone receptor negative, human epidermal growth factor receptor 2 positive, triple negative, and highly proliferative (Ki-67 ≥14%) tumors. The prediction models that included imaging parameters to predict the presence of distant metastasis had higher discriminatory powers than the prediction models that included only histopathological parameters. Primary tumors with higher metabolic-glycolytic activity and higher cellularity were more aggressive and had higher metastatic potential in breast IDC. Compared with histopathological parameters alone, the combination of imaging parameters and histopathological features of primary tumors may help to better understand tumor biology and behavior.

An engineered niche delineates metastatic potential of breast cancer.

Metastatic breast cancer is often not diagnosed until secondary tumors have become macroscopically visible and millions of tumor cells have invaded distant tissues. Yet, metastasis is initiated by a cascade of events leading to formation of the pre-metastatic niche, which can precede tumor formation by a matter of years. We aimed to distinguish the potential for metastatic disease from nonmetastatic disease at early times in triple-negative breast cancer using sister cell lines 4T1 (metastatic), 4T07 (invasive, nonmetastatic), and 67NR (nonmetastatic). We used a porous, polycaprolactone scaffold, that serves as an engineered metastatic niche, to identify metastatic disease through the characteristics of the microenvironment. Analysis of the immune cell composition at the scaffold was able to distinguish noninvasive 67NR tumor-bearing mice from 4T07 and 4T1 tumor-bearing mice but could not delineate metastatic potential between the two invasive cell lines. Gene expression in the scaffolds correlated with the up-regulation of cancer hallmarks (e.g., angiogenesis, hypoxia) in the 4T1 mice relative to 4T07 mice. We developed a 9-gene signature (Dhx9, Dusp12, Fth1, Ifitm1, Ndufs1, Pja2, Slc1a3, Soga1, Spon2) that successfully distinguished 4T1 disease from 67NR or 4T07 disease throughout metastatic progression. Furthermore, this signature proved highly effective at distinguishing diseased lungs in publicly available datasets of mouse models of metastatic breast cancer and in human models of lung cancer. The early and accurate detection of metastatic disease that could lead to early treatment has the potential to improve patient outcomes and quality of life.

Abstract B023: Oncostatin M induces HIF1A-dependent collective cell migration in mammary epithelial cells

Abstract Over 40,000 deaths due to breast cancer occur annually in the United States, and metastatic status is the most important determinant in prognosis. The metastatic potential of cancer cells is strongly influenced by interactions with the tumor microenvironment, which are mediated in large part by growth factors and cytokines that can modulate cellular phenotype. One such ligand is Oncostatin M (OSM), a cytokine produced by macrophages in breast cancer tumors. An emerging body of literature suggests that OSM is capable of shifting cancer cells into a metastatic cell state, however the mechanistic relationship between OSM signaling and cancer progression remains unclear. Gaining a better understanding of the molecular and microenvironmental factors that promote metastasis is critical for design of therapeutic strategies that can mitigate metastasis for patients with breast cancer. In previous studies, we found that MCF10A mammary epithelial cells exposed to OSM form multicellular clusters that migrate collectively, a process termed collective cell migration (CCM). This migratory phenotype has been linked to an increase in metastatic potential in breast cancer and provides an explanation for the association between OSM and cancer progression. Understanding the mechanism that underlies OSM-induced CCM may reveal how this phenotype contributes to metastasis. Toward this goal, we performed RNAseq and proteomic profiling of OSM-treated MCF10A cells, which revealed broad changes in molecular activity. Notably, OSM induced upregulation of transcription factors associated with migration (e.g., CEBPB, HIF1A) as well as a set of transcripts that contribute to cell junction formation (e.g., CDH3, GJA1). Network analysis revealed key nodes that may be associated with the phenotypic response, and functional screening with siRNA knock-down identified HIF1A as an essential mediator of OSM-induced CCM. Cellular activation of HIF1A is typically observed in response to hypoxia, a microenvironmental condition commonly found in human breast tumors, and patients with increased HIF1A expression have been found to be at a greater risk of metastasis. Our findings suggest that OSM released from tumor infiltrating myeloid cells may offer an alternative hypoxia-independent pathway to induce tumor cell upregulation of HIF1A and activation of metastatic cascades. Single-cell RNA-seq will be utilized to identify the transcriptional programs regulated by HIF1A in OSM-treated MCF10A cells. To further explore this hypothesis, we have performed additional experiments investigating the HIF1A signaling axis using organoids derived from MMTV-PyMT mice, cultured ex vivo in collagen gels. Initial results indicate that exposure to OSM increase cancer cell invasion in this mouse model of breast cancer. Future experiments will explore the relationship between HIF1A activation and MMTV-PyMT invasion and dissemination. Collectively, these results demonstrate an important connection between OSM, HIF1A, and CCM and help clarify the signaling consequences of OSM on cancer cell invasion. Citation Format: Ian C. McLean. Oncostatin M induces HIF1A-dependent collective cell migration in mammary epithelial cells [abstract]. In: Proceedings of the AACR Special Conference: Cancer Metastasis; 2022 Nov 14-17; Portland, OR. Philadelphia (PA): AACR; Cancer Res 2022;83(2 Suppl_2):Abstract nr B023.

The Effect of Smoking on Endocrine Therapy for Stage IV Hormone Receptor Positive Breast Cancer.

Smoking worsens breast cancer prognosis. It has been reported that tobacco components directly reach the mammary gland tissue, causing smoking-related DNA damage and biological effects. We hypothesized that smoking may have characteristics that affect the therapeutic effect and clinical course in patients with stage IV hormone receptor-positive breast cancer (HRBC) who received endocrine therapy as the first-line treatment. Fifty-six patients diagnosed with stage IV HRBC were treated with endocrine therapy as the first-line treatment. Before treatment, the period and amount of smoking were confirmed through patient interviews, and each pack-year was recorded. Disease progression with new metastases was more frequent in smokers than non-smokers during endocrine therapy as first-line treatment (p=0.034). Furthermore, as the pack-year increased, new metastases tended to appear [pack-year ≤15; hazard ratio (HR)=1.929, p=0.507; pack-year 15-30, HR=3.857, p=0.223; pack-year >30, HR=7.714, p=0.028]. In stage IV HRBC, smoking increases the metastatic potential of breast cancer, suggesting that changes in its biology may lead to poor prognosis.

Abstract 964: Tumor cell plasticity promotes metastasis across heterogeneous tumors

Abstract Metastasis, the growth of secondary tumors in distant organs, is the major cause of cancer-related deaths due to insufficient therapeutic effects of conventional treatment. Individual tumor cells exhibit heterogeneous features and growth potentials within the same tumor that may influence metastasis formation. During the metastatic cascade, tumor cells adapt their phenotype to various microenvironments that are distinct from their original site resulting in heterogeneous metastatic cells that often are resistant to conventional treatment. The underlying mechanisms of why some tumor cells can give rise to metastases, whereas others cannot are remarkably poorly understood. We established patient-derived xenograft (PDX) models of breast cancer with different metastatic potential and preserved tumor heterogeneity. We analyzed the intrinsic cellular programs of individual tumor cells that influence the metastatic potential of breast cancers using different single-cell RNA-sequencing protocols (MULTI-Seq and Smart-Seq2). Using gene expression profiling of matched primary tumor and metastatic cells of 13 human breast cancers, we demonstrated that while human tumors showed profound inter-patient heterogeneity, they also shared signatures of differentially expressed genes between primary tumor and metastatic cells. Tumors with similar metastatic capabilities shared similar signatures, suggesting potential targets to directly treat metastasis. Additionally, we found that the plasticity of tumor cells is a common feature across tumors that is beneficial for the formation of metastasis. Tumors with higher levels of plastic tumor cells have a greater ability to form metastases. Moreover, we identified a subset of tumor cells expressing both markers of epithelial and mesenchymal characteristics, demonstrating in-vivo evidence for tumor epithelial-mesenchymal plasticity (EMP) in the metastatic cascade. The EMP is a continuum of states with epithelial and mesenchymal cell states as the two extremes of this continuum. The identified transition cells express distinct markers suggesting that these cells may represent a novel and overlooked cell type within the EMP continuum. Given the importance of tumor plasticity in the metastatic cascade, inhibiting the subset of tumor cells that are currently undergoing EMP may represent a novel treatment strategy for metastasis. Citation Format: Juliane Winkler, Weilun Tan, Angela O. Pisco, Andrei Goga, Spyros Darmanis, Zena Werb. Tumor cell plasticity promotes metastasis across heterogeneous tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 964.

Abstract 983: RNA-seq analysis of murine liver to identify breast cancer metastatic potential during liver involution

Abstract Background: Postpartum breast cancer (PPBC), variably defined as breast cancer diagnosed within 5-10 years after a patient’s last pregnancy, has overall increased risk of metastasis even after controlling for patient age, year of diagnosis, and tumor subtype and stage. Metastasis to the liver is specifically increased in PPBC compared to non-PPBC cases and likely contributes to the overall poor prognosis of PPBC. Our lab has previously shown that the rodent liver undergoes physiological remodeling after pregnancy, in a process reminiscent of weaning-induced mammary gland involution. Further, rodent models confirm that breast cancer cells delivered to the involuting liver grow more robustly than tumor cells delivered to nulliparous liver. Our rodent data suggest that weaning induced liver involution may be responsible for increased tumor cell seeding and ultimately higher rates of liver metastasis observed in women diagnosed with PPBC. Since weaning-induced liver involution is a recently recognized physiology, little is known of its molecular underpinnings. Here we employ RNA-seq of murine livers to better understand how reproductive status influences liver physiology with a focus on exploring the pro-metastatic niche formed after weaning. Study design: Livers were isolated from age-matched mice at the following reproductive time points: nulliparous (never pregnant), lactation, involution days 2, 4, 6, and 8, and fully regressed (4 weeks post-wean) and flash frozen for RNA isolation (n=3-6 mice per group). RNA-seq was utilized to identify gene expression differences between reproductive groups. We employed single-sample gene set enrichment analysis (ssGESA) to identify key pathways modulated by reproductive state. Results: We identify clear reproductive control of liver physiology. We find increases in proliferation, MTORC1, and anabolic metabolism pathways during lactation when compared to any other reproductive state. In the transition from lactation to involution, we find increases in apoptotic pathways, and a switch to catabolic metabolism. Correspondingly, during involution we see enrichment in pro-cancer pathways including increased TGFβ signaling, Epithelial to Mesenchymal Transition, and Inflammatory Responses Hallmark Pathways. Within the immune signatures changes of involution, we observe myeloid-derived cell signatures including enrichment in M2 associated genes, and increases in cytotoxic and helper T cell signatures that parallels a signature for disease-specific T cell exhaustion. Conclusion: This work highlights novel regulation of liver physiology by reproductive state, and finds pathways regulated during the natural physiological process of involution that have been previously identified as contributing to metastatic niches. This study has the potential to identify new targets for the prevention and treatment of breast cancer liver metastasis. Citation Format: Michelle K. Ozaki, Alexandra Q. Bartlett, Zheng Xia, Pepper Schedin. RNA-seq analysis of murine liver to identify breast cancer metastatic potential during liver involution [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 983.

Silver Nanoparticles Inhibit Metastasis of 4T1 Tumor in Mice after Intragastric but Not Intravenous Administration.

The potential anticancer activity of different silver nanoformulations is increasingly recognized. In the present work, we use the model of 4T1 tumor in BALB/ccmdb immunocompetent mice to analyze the impact of citrate- and PEG-coated silver nanoparticles (AgNPs) on the development and metastatic potential of breast cancer. One group of mice was intragastrically administered with 1 mg/kg body weight (b.w.) of AgNPs daily from day 1 to day 14 after cancer cells implantation (total dose 14 mg/kg b.w.). The second group was intravenously administered twice with 1 or 5 mg/kg b.w. of AgNPs. A tendency for lowering tumor volume on day 21 (mean volumes 491.31, 428.88, and 386.83 mm3 for control, AgNPs-PEG, and AgNPs-citrate, respectively) and day 26 (mean volumes 903.20, 764.27, and 672.62 mm3 for control, AgNPs-PEG, and AgNPs-citrate, respectively) has been observed in mice treated intragastrically, but the effect did not reach the level of statistical significance. Interestingly, in mice treated intragastrically with citrate-coated AgNPs, the number of lung metastases was significantly lower, as compared to control mice (the mean number of metastases 18.89, 14.90, and 8.03 for control, AgNPs-PEG, and AgNPs-citrate, respectively). No effect of AgNPs treatment on the number of lung metastases was observed after intravenous administration (the mean number of metastases 12.44, 9.86, 12.88, 11.05, and 10.5 for control, AgNPs-PEG 1 mg/kg, AgNPs-PEG 5 mg/kg, AgNPs-citrate 1 mg/kg, and AgNPs-citrate 5 mg/kg, respectively). Surprisingly, inhibition of metastasis was not accompanied by changes in the expression of genes associated with epithelial–mesenchymal transition. Instead, changes in the expression of inflammation-related genes were observed. The presented results support the antitumor activity of AgNPs in vivo, but the effect was limited to the inhibition of metastasis. Moreover, our results clearly point to the importance of AgNPs coating and route of administration for its anticancer activity. Finally, our study supports the previous findings that antitumor AgNPs activity may depend on the activation of the immune system and not on the direct action of AgNPs on cancer cells.

Syntaxin4-Munc18c Interaction Promotes Breast Tumor Invasion and Metastasis by Regulating MT1-MMP Trafficking.

Disrupting the interaction of Syntaxin4 and Munc18c may be a useful approach to perturb trafficking of MT1-MMP and reduce metastatic potential of breast cancers.

ErbB2 promotes breast cancer metastatic potential via HSF1/LDHA axis-mediated glycolysis.

ErbB2 is overexpressed in approximately 25% of breast cancer cases and promotes metastatic potential. We previously reported that ErbB2 promoted glycolysis via heat shock factor 1 (HSF1)/lactate dehydrogenase A (LDHA) axis and ErbB2-mediated glycolysis was required for the growth of breast cancer cells. However, the importance of HSF1/LDHA axis-mediated glycolysis in ErbB2-enhanced metastatic potential remains to be elucidated. In this study, we investigated the effect of HSF1/LDHA axis-mediated glycolysis on migration and invasion in breast cancer cells. Firstly, we demonstrated that ErbB2-mediated migration and invasion were dependent on glycolysis in breast cancer cells. Secondly, we found that HSF1/LDHA axis played an important role in glycolysis, which contributed to ErbB2-enhanced migration and invasion. Finally, we showed that ErbB2 was positively correlated with HSF1/LDHA axis in invasive breast cancer patients via GEO analysis. Taken together, ErbB2 promoted metastatic potential of breast cancer cells via HSF1/LDHA axis-mediated glycolysis. And our findings indicated that targeting HSF1/LDHA axis may be a promising strategy to treat ErbB2-overexpressing breast cancer patients.

The Predictive Role of Serum Levels of Soluble Cell Adhesion Molecules (sCAMs) in the Therapy of Advanced Breast Cancer-A Single-Centre Study.

Background and Objectives: Soluble cell adhesion molecules (sCAMs) play a significant role in the metastatic potential of breast cancer (BC). They might block lymphocytes and promote angiogenesis and migration of cancer cells. We assessed the usefulness of sCAMs in the prognosis and monitoring of the progression of advanced BC. Materials and Methods: We assessed soluble E-selectin, P-selectin, VCAM-1, ICAM-1, EpCAM, IL-6Ra, TNF-R1, and TNF-R2 in 39 women with aBC. Blood samples were obtained at the beginning of the treatment and after 2 months. Results: The median progression-free survival (PFS) was 9 months, and overall survival (OS) was 27 months. The higher levels of sICAM-1 (HR = 2.60, p = 0.06) and lower levels of sEpCAM (HR = 2.72, p < 0.05) were associated with faster progression of aBC. High levels of sEpCAM through the follow-up period were significantly associated with a lower risk of progression (HR = 0.40, p < 0.01). We found the independent predictive value of higher than median sICAM-1 levels for PFS (HR = 2.07, p = 0.08) and of sVCAM-1 levels for OS (HR = 2.59, p < 0.05). Conclusions: Our data support the predictive value of sICAM-1 and sVCAM-1 and suggest that they could become markers for tailoring new therapies in aBC. sEpCAM level could be used as an early indicator of response to the therapy.

MiR-125a-5p impairs the metastatic potential in breast cancer via IP6K1 targeting.

The deregulation of PI3K/Akt signaling is among the most causes in inducing the acquisition of a metastatic phenotype in breast cancer cells, leading to Epithelial-Mesenchymal Transition (EMT). Inhibition of the PI3K/Akt pathway is known to be beneficial in the clinical setting. However, the activation of secondary pathways and toxicity profiles of available inhibitors, hindering optimal therapeutic results. Preliminary studies showed that myo-Inositol inhibits the PI3K/Akt pathway by exerting a pleiotropic anti-tumor action. Herein, we demonstrate that myo-Inositol triggers a prompt and profound remodeling of delineated expression pattern in triple-negative breast cancer cells (MDA-MB-231). Consequently, it inhibits metastasis and tumor progression through miR-125a-5p transcription and the subsequent inhibition of IP6K1. In contrast, hormone-responsive breast cancer cells (MCF-7) are insensitive to myo-Inositol. This is due to the persistence of MDM2 synthesis promoted by estrogen-dependent pathways. Conversely, the counteraction of estrogen effects recovered the sensitivity to myo-Inositol in the hormone-responsive model. Overall, these results identify a novel axis primed by miR-125a-5p to downregulate IP6K1 gene that inhibits metastasis. Thus, administration of myo-Inositol can activate this axis as a molecular target therapy in breast cancer.

Targeting CD82/KAI1 for Precision Therapeutics in Surmounting Metastatic Potential in Breast Cancer.

Simple SummaryBreast cancer-related deaths are mainly due to the spread of cancer cells to distant organs (a process termed metastasis). CD82, also known as KAI1, is an established metastasis suppressor that has been documented to be lowly expressed in metastatic breast cancer. Hence, CD82 could possibly be a feasible molecular target for impeding metastases in breast cancer patients. Here, we propose a precision oncology-based model of preventing metastases by an appropriate selection of non-metastatic breast cancer patients with low CD82 expression. Potential therapeutic options for restoring CD82 levels that could be administered include the repurposing of existing chemotherapeutic drugs such as tyrosine kinase inhibitors and etoposide, as well as the use of CD82 peptide mimics and non-coding RNA-based therapeutics.Metastasis is the main cause of mortality in breast cancer patients. There is an unmet need to develop therapies that can impede metastatic spread. Precision oncology has shown great promise for the treatment of cancers, as the therapeutic approach is tailored to a specific group of patients who are likely to benefit from the treatment, rather than the traditional approach of “one size fits all”. CD82, also known as KAI1, a glycoprotein belonging to the tetraspanin family and an established metastasis suppressor, could potentially be exploited to hinder metastases in breast cancer. This review explores the prospect of targeting CD82 as an innovative therapeutic approach in precision medicine for breast cancer patients, with the goal of preventing cancer progression and metastasis. Such an approach would entail the selection of a subset of breast cancer patients with low levels of CD82, and instituting an appropriate treatment scheme tailored towards restoring the levels of CD82 in this group of patients. Proposed precision treatment regimens include current modalities of treating breast cancer, in combination with either clinically approved drugs that could restore the levels of CD82, CD82 peptide mimics or non-coding RNA-based therapeutics.

E2F3 drives the epithelial-to-mesenchymal transition, cell invasion, and metastasis in breast cancer.

E2F3 is a transcription factor that may initiate tumorigenesis if overexpressed. Previously, we demonstrated that E2F3 mRNA is overexpressed in breast cancer and that E2F3 overexpression results in centrosome amplification and unregulated mitosis, which can promote aneuploidy and chromosome instability to initiate and sustain tumors. Further, we demonstrated that E2F3 leads to overexpression of the mitotic regulator Shugoshin-1, which until recently had unknown roles in cancer. This study aims to evaluate the roles of E2F3 and Shugoshin-1 in breast cancer metastatic potential. Here we demonstrated that E2F3 and Shugoshin-1 silencing leads to reduced cell invasion and migration in two mesenchymal triple-negative breast cancer (TNBC) cell lines (MDA-MB-231 and Hs578t). Moreover, E2F3 and Shugoshin-1 modulate the expression of epithelial-to-mesenchymal transition-associated genes such as Snail, E-Cadherin, and multiple matrix metalloproteinases. Furthermore, E2F3 depletion leads to reductions in tumor growth and metastasis in NOD-scid Gamma mice. Results from this study suggest a key role for E2F3 and a novel role for Shugoshin-1 in metastatic progression. These results can further help in the improvement of TNBC targeted therapies by interfering with pathways that intersect with the E2F3 and Shugoshin-1 signaling pathways.