Migration Of Breast Cancer Cells Research Articles

NREP, transcriptionally upregulated by HIF-1α, aggravates breast cancer cell growth and metastasis by promoting glycolysis

Breast cancer (BC) poses a great threat to women’s health. Neuronal regeneration related protein (NREP) is a multifunctional protein that is involved in embryonic development, regeneration, and human disease. However, the biological function of NREP in tumors is rarely reported and its role in BC remains unknown. Bioinformatics analysis showed that NREP is highly expressed and closely correlated with poor survival in BC patients. Under hypoxic conditions, NREP was upregulated in BC cells, and this promotion was reversed by hypoxia-inducible factor HIF-1α suppression. Luciferase reporter system and chromatin immunoprecipitation assays confirmed that HIF-1α directly binds to the promoter of NREP to increase the transcriptional activity of NREP. NREP suppression inhibited cell proliferation, arrested the cell cycle at the G1/S phase, and promoted apoptosis and caspase-3 activity in BC cells. Suppression of NREP decreased the tube formation ability of HUVECs. In addition, NREP downregulation showed an inhibition effect on cell migration, invasion, and EMT of BC cells. In NREP overexpressed cells, all these changes were reversed. In vivo, animal experiments also confirmed that NREP promotes BC tumor growth and metastasis. In addition, NREP promoted cellular glycolysis and enhanced the levels of glucose consumption, ATP, lactate production, and glucose transporters expression in NREP-overexpressed BC cells. In summary, our results demonstrated that NREP could be transcriptional activated by HIF-1α, which may aggravate BC tumor growth and metastasis by promoting cellular glycolysis. This result suggested that NREP may play an essential part in BC progression.

Abstract PO1-13-12: Mechanistic Analysis and Potential Therapeutic Implications in Breast Cancer with Fibrotic Focus

Abstract A fibrotic focus (FF) is a scar-like region that forms in the center of carcinoma due to excessive tumor stroma formation. In our earlier studies, we found FF as an independent poor prognostic factor for breast cancers. However, the underlying mechanisms of how the presence of FF contributed to a poor prognosis are still unknown. To improve our understanding of FF in breast cancer, we have investigated genes associated with FF and their impacts on breast cancer prognosis. Analysis of data from The Cancer Genome Atlas Program (TCGA) indicated that Bone Morphogenetic Protein 8A (BMP8A) was significantly upregulated in breast cancers with FF. To further validate this finding, immunohistochemistry (IHC) on BMP8A was performed on a local cohort of breast cancers (N= 900). Of these samples, 147 (16.3%) were found to be BMP8A positive, and there was a significant association between the presence of FF and high expression of BMP8A (p-value=0.026). We also found that high expression of BMP8A was positively correlated with apocrine phenotype, necrosis, increased Ki67 expression, and triple-negative breast cancer subtype; and most of these are poor prognostic factors for breast cancer. Kaplan-Meier survival estimate analysis revealed that high expression of BMP8A was significantly associated with poor overall survival (p-value=0.035). Gene ontology (GO) analysis showed that "Extracellular matrix organization" was the prominent biological process associated with BMP8A. KEGG pathway analysis suggested that BMP8A was significantly related to "Protein digestion and absorption", "ECM-receptor interaction", and "Focal adhesion" pathways, further validating its correlation with stromal FF. In cellular studies using MCF7 and MDA-MB-231 cell lines, overexpression of BMP8A was found to enhance breast cancer cell proliferation, invasion, and migration. Similar tumor-promoting phenotypes were exhibited when stimulating the cell lines with recombinant human BMP8A. In conclusion, our findings suggested that BMP8A was associated with FF in breast cancer, contributing at least partly to the aggressive features of these cancers. Our findings also provided new insights into the precision treatment and diagnosis of breast cancer. Further exploration of BMP8A as a therapeutic target and prognostic factor may contribute to improved management of breast cancer patients. Citation Format: Canbin Fang, Julia Y. S. Tsang, Gary M.K. Tse. Mechanistic Analysis and Potential Therapeutic Implications in Breast Cancer with Fibrotic Focus [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-13-12.

Abstract PO5-06-12: Genetic screen identifies epigenetic drivers of breast cancer brain metastasis

Abstract Metastatic breast cancer remains a major cause of cancer-related deaths in women, and there are few effective therapies against this advanced disease. Brain metastases, found in 15~35% of patients with breast cancer, are often incurable. Accumulating evidence suggests that key steps of tumor progression and metastasis are controlled by reversible epigenetic mechanisms. To systematically identify the druggable epigenetic regulators essential for breast cancer brain metastasis, we conducted an in vivo shRNA screen and identified multiple epigenetic regulators, including RNA acetyltransferase NAT10 as drivers of breast cancer brain metastasis. Knockdown of NAT10 significantly restrains breast cancer cell proliferation and migration in vitro and brain metastases in vivo. NAT10 promotes breast cancer cell growth through its RNA helicase activity but not its acetyltransferase activity. Integrative analyses of transcriptomics, proteomics, and NAT10 eCLIP-Seq data identify NAT10 downstream targets critical for breast cancer progression and metastasis. Thus, these results reveal novel therapeutic strategies to treat metastatic breast cancer. Citation Format: Jocelyn Chen, Wesley Cai, Peng Xu, Don Nguyen, Qin Yan. Genetic screen identifies epigenetic drivers of breast cancer brain metastasis [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO5-06-12.

Oleic acid inhibits the migration and invasion of breast cancer cells with stemness characteristics through oxidative stress-mediated attenuation of the FAK/AKT/NF-κB pathway

Oleic acid, found in a variety of food sources, is beneficial to health. However, studies on its anticancer effects on cancer stem cells resistant to conventional treatments and on the mechanisms underlying such effects are scarce. Here, we evaluated the anticancer effects of oleic acid against breast cancer cells with stemness characteristics. Oleic acid inhibited the proliferation of breast cancer stem-like cells more significantly than that of their respective parental cells, and reduced the expression of stem cell markers and migration and invasion propensity. It also repressed the phosphorylation of FAK, AKT, and NF-κB, proteins involved in cell migration and invasion. Oleic acid-induced increase in reactive oxygen species levels mediated the inhibition of the FAK/AKT/NF-κB signaling axis. Our study demonstrates that oleic acid-induced oxidative stress plays an important role in inhibiting the metastatic behavior of breast cancer cells with stemness characteristics and is relevant for management of treatment-resistant breast cancer.

Acquisition of Doxorubicin Resistance Induces Breast Cancer Cell Migration and Epithelial-Mesenchymal Transition that are Reversed by Shikonin-Metformin Synergy

Background: Drug resistance is a major challenge in cancer chemotherapy. Methods: By adopting an appropriately timed strategy, we generated MCF-7 cell sublines resistant to serial doses of doxorubicin (DOX). Our higher-dose sublines showed more stability in resistance and were, therefore, subjected to further analyses. We tested the consistency of drug resistance by comparing sublines with control groups for growth and migration capacities. Molecular analyses monitored expression changes, CD44/CD24 ratios, and DOX binding to key molecules. The reverting impact of shikonin (SHKN) and metformin (MTFN) on DOX resistance was examined. Results. The resistant sublines grew parallel to or even faster than WT MCF-7 cells and showed a larger and more rounded morphology. The consistency of their drug resistance and invasive potential was demonstrated over time using serial doses of DOX. Real-time PCR revealed upregulation of genes involved in cell growth and survival, drug resistance, migration/invasion, and epithelial-mesenchymal transition and, conversely, downregulation of pro-apoptotic, anti-chemoresistance, and tumor suppressor genes. SHKN-MTFN co-treated resistant cells showed significantly lower CD44/CD24 ratios, less aggressiveness, and reduced survival and migration rates but enhanced apoptosis. SHKN’s affinity to CYP1A and TOP2A demonstrated the importance of these interactions and the compounds’ capacity to compete with DOX. Conclusion: Acquisition of DOX resistance increases tumorigenic properties of cancer cells, whereas synergy between selective anti-tumorigenic compounds re-sensitizes resistant cells by reverting cellular pathways that favor or follow resistance. Our findings suggest that this reversal is supported by competing reactions that deprive DOX of binding to its target molecules.

Anticancer Effects of Mitoquinone via Cell Cycle Arrest and Apoptosis in Canine Mammary Gland Tumor Cells.

Treating female canine mammary gland tumors is crucial owing to their propensity for rapid progression and metastasis, significantly impacting the overall health and well-being of dogs. Mitoquinone (MitoQ), an antioxidant, has shown promise in inhibiting the migration, invasion, and clonogenicity of human breast cancer cells. Thus, we investigated MitoQ's potential anticancer properties against canine mammary gland tumor cells, CMT-U27 and CF41.Mg. MitoQ markedly suppressed the proliferation and migration of both CMT-U27 and CF41.Mg cells and induced apoptotic cell death in a dose-dependent manner. Furthermore, treatment with MitoQ led to increased levels of pro-apoptotic proteins, including cleaved-caspase3, BAX, and phospho-p53. Cell cycle analysis revealed that MitoQ hindered cell progression in the G1 and S phases in CMT-U27 and CF41.Mg cells. These findings were supported using western blot analysis, demonstrating elevated levels of cleaved caspase-3, a hallmark of apoptosis, and decreased expression of cyclin-dependent kinase (CDK) 2 and cyclin D4, pivotal regulators of the cell cycle. In conclusion, MitoQ exhibits in vitro antitumor effects by inducing apoptosis and arresting the cell cycle in canine mammary gland tumors, suggesting its potential as a preventive or therapeutic agent against canine mammary cancer.

LncRNA DDX11-AS1 promotes cell growth, migration and invasion through regulating epithelial-mesenchymal transition in breast cancer.

This study aimed to investigate the expression of long non-coding ribonucleic acid (lncRNA) DDX11 antisense RNA 1 (DDX11-AS1) in breast cancer (BC) tissues and cells and investigate its biological function and potential molecular mechanism through in vitro experiments. Tissue specimens were obtained from 44 BC patients. TRIzol method was used to extract RNAs from the tissues. The relative expression of DDX11-AS1 in BC tissues and the expression of DDX11-AS1 in BC cells were detected via quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The effect of DDX11-AS1 on the proliferation ability of BC cells was detected via cell counting kit-8 (CCK-8) assay. Flow cytometry was adopted to study the effect of DDX11-AS1 on the distribution of BC cell cycle. Transwell assays were performed to analyze the effects of DDX11-AS1 on the migration and invasion abilities of BC cells. Finally, after interfering with the expression of DDX11-AS1 in BC cells, changes in the expressions of molecular markers for epithelial-mesenchymal transition (EMT) were detected via Western blotting. According to the results of qRT-PCR, the expression of DDX11-AS1 was up-regulated in 38 out of 44 cases of BC tissues compared with that in the para-carcinoma tissues, and the expression of DDX11-AS1 in BC cells was up-regulated as well. After interference with the expression of DDX11-AS1 in BC cells, it was found via CCK-8 assay that the proliferation ability of BC cells was restrained, flow cytometry results showed that the BC cell cycle was arrested at G1/G0 phase, and the results of transwell assays revealed that the cell invasion and migration abilities were suppressed in experimental group compared with those in control group. According to the results of Western blotting, after interfering with the expression of DDX11-AS1 in BC cells, there were changes in the expressions of molecular markers for EMT. In BC, the expression of lncRNA DDX11-AS1 is up-regulated, which promotes the proliferation, migration and invasion of BC cells by regulating EMT.

Biological functions of PCAT-1/ SOX4 in cell proliferation and invasion of breast cancer.

Breast cancer (BC) is one of the most common fatal cancers. Recent studies have identified the vital role of long noncoding RNA (lncRNAs) in the development and progression of BC. In this research, lncRNA PCAT-1 was studied to identify how it functioned in the metastasis of BC. PCAT-1 expression of tissues was detected by real-time quantitative polymerase chain reaction (RT-qPCR) in 50 BC patients. Cell proliferation, wound healing assay and transwell assay were used to observe the biological behavior changes of BC cells through knockdown or overexpression of PCAT-1. In addition, RT-qPCR and Western blot assay were performed to discover the potential target protein of PCAT-1 in BC. PCAT-1 expression level in BC samples was higher than that of adjacent ones. Besides, cell proliferation, migrated ability and cell invaded ability of BC cells were inhibited after PCAT-1 was silenced. Cell proliferation, migration and invasion of BC cells were promoted after PCAT-1 was overexpressed. In addition, SOX4 was downregulated after silence of PCAT-1 in BC cells, while SOX4 was upregulated after overexpression of PCAT-1 in BC cells. Furthermore, SOX4 was upregulated in BC tissues and was positively associated with PCAT-1. Our study uncovers a new oncogene in BC and suggests that PCAT-1 could enhance BC cell proliferation, migration and invasion via targeting SOX4, which provided a novel therapeutic target for BC patients.

Effect of Nigella sativa L. extract and thymoquinone on the genes responsible for cell proliferation, migration and NK cell cytotoxicity in breast cancer

Effect of Nigella sativa L. extract and thymoquinone on the genes responsible for cell proliferation, migration and NK cell cytotoxicity in breast cancer

Triclocarban and triclosan promote breast cancer progression in vitro and in vivo via activating G protein-coupled estrogen receptor signaling pathways

Triclocarban (TCC) and triclosan (TCS) have been detected ubiquitously in human body and evoked increasing concerns. This study aimed to reveal the induction risks of TCC and TCS on triple negative breast cancer through non-genomic GPER-mediated signaling pathways. Molecular simulation indicated that TCC exhibited higher GPER binding affinity than TCS theoretically. Calcium mobilization assay displayed that TCC/TCS activated GPER signaling pathway with the lowest observed effective concentrations (LOEC) of 10 nM/100 nM. TCC and TCS also upregulated MMP-2/9, EGFR, MAPK3 but downregulated MAPK8 via GPER-mediated signaling pathway. Proliferation assay showed that TCC/TCS induced 4 T1 breast cancer cells proliferation with the LOEC of 100 nM/1000 nM. Wound-healing and transwell assays showed that TCC/TCS promoted 4 T1 cells migration in a concentration-dependent manner with the LOEC of 10 nM. The effects of TCC on breast cancer cells proliferation and migration were stronger than TCS and both were regulated by GPER. TCC/TCS induced migratory effects were more significantly than proliferative effect. Mechanism study showed that TCC/TCS downregulated the expression of epithelial marker (E-cadherin) but upregulated mesenchymal markers (snail and N-cadherin), which was reversed by GPER inhibitor G15. These biomarkers results indicated that TCC/TCS-induced 4 T1 cells migration was a classic epithelial to mesenchymal transition mechanism regulated by GPER signaling pathway. Orthotopic tumor model verified that TCC promoted breast cancer in-situ tumor growth and distal tissue metastasis via GPER-mediated signaling pathway at human-exposure level of 10 mg/kg/d. TCC-induced tissue metastasis of breast cancer was more significantly than in-situ tumor growth. Overall, we demonstrated for the first time that TCC/TCS could activate the GPER signaling pathways to induce breast cancer progression.

Upregulation of FGF9 and NOVA1 in cancer-associated fibroblasts promotes cell proliferation, invasion and migration of triple negative breast cancer.

Cancer-associated fibroblasts (CAFs) play a pivotal role in cancer progression. This study aimed to explore the roles of CAFs-derived Fibroblast growth factor 9 (FGF9) and Neuro-oncological ventral antigen 1 (NOVA1) in triple negative breast cancer (TNBC) progression. MDA-MB-231 and BT-549 cells were cocultured with CAF conditioned-medium (CAF-CM) or normal fibroblasts conditioned-medium (NF-CM). MTT, EdU, colony formation, wound healing, transwell migration, and invasion assays were employed to determine cell proliferation, migration and invasion, respectively. Western blot and RT-qPCR were carried out to examine the protein and mRNA expression of FGF9 and NOVA1. Xenograft tumor experiments were conducted to evaluate the effects of CAFs, FGF9, and NOVA1 on tumor growth in vivo. Our results showed that CAFs significantly promoted the proliferation, invasion, and migration of TNBC cells. FGF9 and NOVA1 were significantly upregulated in TNBC CAFs, tissues and cells. CAF-CM also could increase the expression of FGF9 and NOVA1 in TNBC cells. Knockdown of FGF9 or NOVA1 could hamper cell proliferation, invasion, migration, and EMT of TNBC cells. Moreover, CAFs with FGF9/NOVA1 knockdown also could inhibit TNBC progression. Besides, CAFs significantly accelerated tumor growth in vivo, which was blocked by FGF9/NOVA1 knockdown in nude mice. In conclusion, our results indicated the tumor-promoting role of CAFs in TNBC progression. FGF9 and NOVA1 upregulation in CAFs induced cell proliferation, migration and invasion in vitro, and facilitated tumor growth in vivo in TNBCdevelopment.

Self-Augmented Reactive Oxygen Species-Responsive Nanoformulation with Efficient Curcumin Delivery for Inhibiting Triple-Negative Breast Cancer Cell Growth and Migration

Self-Augmented Reactive Oxygen Species-Responsive Nanoformulation with Efficient Curcumin Delivery for Inhibiting Triple-Negative Breast Cancer Cell Growth and Migration

Toxoplasma gondii suppresses proliferation and migration of breast cancer cells by regulating their transcriptome

BackgroundBreast cancer is the most common cancer in women worldwide. Toxoplasma gondii (T. gondii) has shown anticancer activity in breast cancer mouse models, and exerted beneficial effect on the survival of breast cancer patients, but the mechanism was unclear.MethodsThe effect of tachyzoites of T. gondii (RH and ME49 strains) on human breast cancer cells (MCF-7 and MDA-MB-231 cells) proliferation and migration was assessed using cell growth curve and wound healing assays. Dual RNA-seq was performed for T. gondii-infected and non-infected cells to determine the differentially expressed genes (DEGs). Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Protein–Protein Interaction Networks analysis (PPI) were performed to explore the related signaling pathway and hub genes. Hub genes were validated using the Kaplan–Meier plotter database, and Pathogen Host Interaction (PHI-base) database. The results were verified by qRT-PCR.ResultsThe tachyzoites of T. gondii decreased the expression of Ki67 and increased the expression of E-cadherin, resulting in suppressing the proliferation and migration of infected human breast cancer cells. The inhibitory effect of T. gondii on breast cancer cells showed a significant dose–response relationship. Compared with the control group, 2321 genes were transcriptionally regulated in MCF-7 cells infected with T. gondii, while 169 genes were transcriptionally regulated in infected MDA-MB-231 cells. Among these genes, 698 genes in infected MCF-7 cells and 67 genes in infected MDA-MB-231 cells were validated by the publicly available database. GO and KEGG analyses suggested that several pathways were involved in anticancer function of T. gondii, such as ribosome, interleukin-17 signaling, coronavirus disease pathway, and breast cancer pathway. BRCA1, MYC and IL-6 were identified as the top three hub genes in infected-breast cancer cells based on the connectivity of PPI analysis. In addition, after interacting with breast cancer cells, the expression of ROP16 and ROP18 in T. gondii increased, while the expression of crt, TgIST, GRA15, GRA24 and MIC13 decreased.ConclusionsT. gondii transcriptionally regulates several signaling pathways by altering the hub genes such as BRCA1, MYC and IL-6, which can inhibit the breast tumor growth and migration, hinting at a potential therapeutic strategy.

GATA4 regulates the transcription of MMP9 to suppress the invasion and migration of breast cancer cells via HDAC1-mediated p65 deacetylation

GATA-binding protein 4 (GATA4) is recognized for its significant roles in embryogenesis and various cancers. Through bioinformatics and clinical data, it appears that GATA4 plays a role in breast cancer development. Yet, the specific roles and mechanisms of GATA4 in breast cancer progression remain elusive. In this study, we identify GATA4 as a tumor suppressor in the invasion and migration of breast cancer. Functionally, GATA4 significantly reduces the transcription of MMP9. On a mechanistic level, GATA4 diminishes MMP9 transcription by interacting with p65 at the NF-κB binding site on the MMP9 promoter. Additionally, GATA4 promotes the recruitment of HDAC1, amplifying the bond between p65 and HDAC1. This leads to decreased acetylation of p65, thus inhibiting p65’s transcriptional activity on the MMP9 promoter. Moreover, GATA4 hampers the metastasis of breast cancer in vivo mouse model. In summary, our research unveils a novel mechanism wherein GATA4 curtails breast cancer cell metastasis by downregulating MMP9 expression, suggesting a potential therapeutic avenue for breast cancer metastasis.

Prognostic biomarker NRG2 correlates with autophagy and epithelial‑mesenchymal transition in breast cancer.

Breast cancer (BRCA) is a leading cause of death in women worldwide, accounting for 31% of female cancer. Autophagy plays a crucial role in cancer progression, however, the function of autophagy-related gene neuroregulatory protein 2 (NRG2) in BRCA and its underlying molecular mechanisms remain unclear. In the present study, the expression of the NRG2 gene in BRCA was significantly down-regulated compared with the normal controls. The low expression level of NRG2 was related to poor survival rate of BRCA. The receiver operating characteristic curve of NRG2 showed a good diagnostic value for distinguishing BRCA from normal tissues (AUC=0.932). GO-KEGG analysis and GSEA enrichment analysis showed that NRG2 and its regulated genes were enriched in autophagy-related and immune-related pathways, and NRG2 was positively correlated with a number of immune cells and immune checkpoint genes. In addition, knockdown of NRG2 significantly promoted the proliferation, invasion and migration of BRCA cells. The autophagy marker, LC3-II and epithelial-mesenchymal transition (EMT) marker, vimentin were increased, while P62 and E-cadherin were decreased in response to NRG2 depletion. The findings of the present study demonstrated that NRG2 acts as a tumor suppressor factor that contributes to the immune escape and anti-tumor immunity inhibition by regulating the pathological process of autophagy and EMT, suggesting that NRG2 could be used as a prognostic biomarker and clinical target for BRCA therapy.

Exosomal miRNA-92a derived from cancer-associated fibroblasts promote invasion and metastasis in breast cancer by regulating G3BP2

Cancer-associated Fibroblasts (CAFs) exert a tumor-promoting effect in various cancers, including breast cancer. CAFs secrete exosomes containing miRNA and proteins, influencing the tumor microenvironment. In this study, we identified CAF-derived exosomes that transport functional miR-92a from CAFs to tumor cells, thereby intensifying the aggressiveness of breast cancer. CAFs downregulate the expression of G3BP2 in breast cancer cells, and a significant elevation in miR-92a levels in CAF-derived exosomes was observed. Both in vitro and in vivo experiments demonstrate that miR-92a enhances breast cancer cell migration and invasion by directly targeting G3BP2, functioning as a tumor-promoting miRNA. We validated that the RNA-binding proteins SNRPA facilitate the transfer of CAF-derived exosomal miR-92a to breast cancer cells. The reduction of G3BP2 protein by CAF-derived exosomes releases TWIST1 into the nucleus, promoting epithelial-mesenchymal transition (EMT) and further exacerbating breast cancer progression. Moreover, CAF-derived exosomal miR-92a induces tumor invasion and metastasis in mice. Overall, our study reveals that CAF-derived exosomal miR-92a serves as a promoter in the migration and invasion of breast cancer cells by reducing G3BP2 and may represent a potential novel tumor marker for breast cancer.

ScRNA-seq characterizing the heterogeneity of fibroblasts in breast cancer reveals a novel subtype SFRP4+ CAF that inhibits migration and predicts prognosis.

Cancer-associated fibroblasts (CAFs) are a diverse group of cells that significantly impact the tumor microenvironment and therapeutic responses in breast cancer (BC). Despite their importance, the comprehensive profile of CAFs in BC remains to be fully elucidated. To address this gap, we utilized single-cell RNA sequencing (scRNA-seq) to delineate the CAF landscape within 14 BC normal-tumor paired samples. We further corroborated our findings by analyzing several public datasets, thereby validating the newly identified CAF subtype. Additionally, we conducted coculture experiments with BC cells to assess the functional implications of this CAF subtype. Our scRNA-seq analysis unveiled eight distinct CAF subtypes across five tumor and six adjacent normal tissue samples. Notably, we discovered a novel subtype, designated as SFRP4+ CAFs, which was predominantly observed in normal tissues. The presence of SFRP4+ CAFs was substantiated by two independent scRNA-seq datasets and a spatial transcriptomics dataset. Functionally, SFRP4+ CAFs were found to impede BC cell migration and the epithelial-mesenchymal transition (EMT) process by secreting SFRP4, thereby modulating the WNT signaling pathway. Furthermore, we established that elevated expression levels of SFRP4+ CAF markers correlate with improved survival outcomes in BC patients, yet paradoxically, they predict a diminished response to neoadjuvant chemotherapy in cases of triple-negative breast cancer. This investigation sheds light on the heterogeneity of CAFs in BC and introduces a novel SFRP4+ CAF subtype that hinders BC cell migration. This discovery holds promise as a potential biomarker for refined prognostic assessment and therapeutic intervention in BC.

Tubulin alpha-1b chain was identified as a prognosis and immune biomarker in pan-cancer combing with experimental validation in breast cancer

The α-tubulin subtype, Tubulin α-1b chain (TUBA1B), has been shown to influence immune cell infiltration, cancer growth, and survival across various malignancies. However, a comprehensive study has not yet been undertaken examining the immunological and predictive effects of TUBA1B in a pan-carcinoma context. Using data from TCGA, GEO, and other databases, we analyzed TUBA1B expression across various carcinoma types using transcriptional profiling, prognostic implications, genetic and epigenetic alterations, methylation patterns, and immunological significance. To validate our findings, we conducted Western blot analysis to assess TUBA1B protein levels in matched breast cancer tissue samples and performed CCK-8 proliferation assay, flow cytometry, transwell invasion, and migration assays to comprehensively examine the functional impact of TUBA1B on breast cancer cells. Our pan-cancer analysis found TUBA1B upregulation across most tumor types, with varying expression patterns in distinct immune and molecular subtypes. High TUBA1B expression was an independent risk factor and associated with poor prognoses in several cancers, including BRCA, KICH, LGG, LUAD, and MESO. TUBA1B also demonstrates moderate to high diagnostic accuracy in most tumor types. Increased m6A methylation levels were observed in the TUBA1B gene, while its promoter region displayed low methylation levels. TUBA1B's expression impacted some cancers by elevating tumor mutation burden, microsatellite instability, neoantigen formation, immune cell infiltration, and the modulation of immune checkpoints. Functional enrichment analysis highlights TUBA1B’s involvement in important cellular processes such as the cell cycle, p53 signaling, cell senescence, programmed cell death, and the regulation of immune-related pathways. Moreover, our study reveals higher TUBA1B protein expression in breast cancer tissues compared to adjacent tissues. In vitro experiments confirm that TUBA1B deletion reduces breast cancer cell proliferation, invasion, and migration while increasing apoptosis. In conclusion, our study suggests that TUBA1B could potentially serve as a diagnostic marker for predicting cancer immunological profiles and survival outcomes and shed light on the expression and role of TUBA1B in breast cancer, providing a solid foundation for considering it as a promising therapeutic target for breast cancer patient treatment.

Hyaluronic acid-based injectable formulation developed to mitigate metastasis and radiation-induced skin fibrosis in breast cancer treatment

The standard treatment for early-stage breast cancer involves breast-conserving surgery followed by adjuvant radiotherapy. However, approximately 20 % of patients experience distant metastasis, and adjuvant radiotherapy often leads to radiation-induced skin fibrosis (RISF). In this study, we develop an on-site injectable formulation composed of selenocystamine (SeCA) and hyaluronic acid (HyA), referred to as SeCA cross-linked HyA (SCH) agent, and investigate its potential to mitigate metastasis and prevent RISF associated with breast cancer therapy. SCH agents are synthesized using the nanoprecipitation method to modulate cell-cell tight junctions and tissue inflammation. The toxicity assessments reveal that SCH agents with a higher Se content (Se payload 17.4 μg/mL) are well tolerated by L929 cells compared to SeCA (Se payload 3.2 μg/mL). In vitro, SCH agents significantly enhance cell–cell tight junctions and effectively mitigate migration and invasion of breast cancer cells (4T1). In vivo, SCH agents mitigate distant lung metastasis. Furthermore, in animal models, SCH agents reduce RISF and promote wound repair. These findings highlight the potential of SCH agents as a novel therapeutic formulation for effectively mitigating metastasis and reducing RISF. This holds great promise for improving clinical outcomes in breast cancer patients undergoing adjuvant radiotherapy.

Long non‑coding RNA DANCR aggravates breast cancer through the miR‑34c/E2F1 feedback loop.

Emerging scientific evidence has suggested that the long non‑coding (lnc)RNA differentiation antagonizing non‑protein coding RNA (DANCR) serves a significant role in human tumorigenesis and cancer progression; however, the precise mechanism of its function in breast cancer remains to be fully understood. Therefore, the objective of the present study was to manipulate DANCR expression in MCF7 and MDA‑MB‑231 cells using lentiviral vectors to knock down or overexpress DANCR. This manipulation, alongside the analysis of bioinformatics data, was performed to investigate the potential mechanism underlying the role of DANCR in cancer. The mRNA and/or protein expression levels of DANCR, miR‑34c‑5p and E2F transcription factor 1 (E2F1) were assessed using reverse transcription‑quantitative PCR and western blotting, respectively. The interactions between these molecules were validated using chromatin immunoprecipitation and dual‑luciferase reporter assays. Additionally, fluorescence in situ hybridization was used to confirm the subcellular localization of DANCR. Cell proliferation, migration and invasion were determined using 5‑ethynyl‑2'‑deoxyuridine, wound healing and Transwell assays, respectively. The results of the present study demonstrated that DANCR had a regulatory role as a competing endogenous RNA and upregulated the expression of E2F1 by sequestering miR‑34c‑5p in breast cancer cells. Furthermore, E2F1 promoted DANCR transcription by binding to its promoter in breast cancer cells. Notably, the DANCR/miR‑34c‑5p/E2F1 feedback loop enhanced cell proliferation, migration and invasion in breast cancer cells. Thus, these findings suggested that targeting DANCR may potentially provide a promising future therapeutic strategy for breast cancer treatment.