Expression In Breast Cancer Tissues Research Articles

Loss of miR-634 contributes to the formation FOXA1-positive triple negative breast cancer subtype

BackgroundTriple-negative breast cancer (TNBC), the most aggressive subtype of breast cancer, lacks targeted therapies, posing a substantial challenge for treatment. Therefore, investigating its pathogenesis is a crucial research focus. FOXA1 and miR-634 are involved in tumorigenesis. However, the molecular mechanisms underlying the aberrant upregulation of FOXA1 expression in TNBC remain unclear. Therefore, we explore the role of miR-634 in the FOXA1-positive TNBC subtype.MethodsQuantitative reverse transcription polymerase chain reaction was used to detect miR-634 expression in breast cancer tissues and cell lines. Aberrantly activated signaling pathways and related genes in TNBC were analyzed using The Cancer Genome Atlas. The potential target of miR-634 was predicted by TargetScan, the TNBC cell proliferation rate was detected using an MTT assay, the in vitro metastatic capacity was determined by transwell assay and the cell cycle distribution was tested using flow cytometry. Western blotting was performed to measure the expression of proteins involved in the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway.ResultsThe expression of miR-634 was significantly down-regulated in both TNBC tissues and cells, compared with adjacent non-cancerous tissues and MCF10A, respectively. Ectopic expression of miR-634 inhibits breast cancer cell proliferation and in vitro metastasis. The TCGA-based expression profile analysis of TNBC revealed that aberrantly activated PI3K/AKT signaling may contribute to its malignant phenotype. FOXA1, the top hit of aberrantly upregulated genes in TNBC, was a direct target of miR-643. Moreover, forced expression of miR-643 drastically suppressed FOXA1 expression by the inactivation PI3K/AKT signaling.ConclusionMiR-634 suppresses FOXA1 to inhibit the proliferation and metastasis of TNBC cells by inactivating the PI3K/AKT signaling pathway.

α-Parvin Expression in Breast Cancer Tissues: Correlation with Clinical Parameters and Prognostic Significance.

Stromal cells play a critical role in the tumor microenvironment of breast cancer (BC), as they are recruited by tumor cells and regulate the metastatic spread. Though high expression of α-parvin, a member of the parvin family of actin-binding proteins, is reported to be associated with a poor prognosis and metastasis in several cancers, its role in carcinogenesis has not been thoroughly explored. Therefore, we aimed to examine the expression of α-parvin in BC patients by compartmentalizing and quantifying tissues to determine whether α-parvin can be a potential therapeutic target. We performed immunohistochemical (IHC) staining of α-parvin in BC tissues, and the IHC scores were calculated in the overall tissue, stroma, and epithelium using image analysis software. The expression of α-parvin was significantly higher in BC tissues (p = 0.0002) and BC stroma (p < 0.0001) than in normal tissues. Furthermore, all α-parvin scores were significantly positively correlated with the proliferation marker Ki67. The overall and stroma scores are associated with the tumor, (lymph) node, and metastasis (TNM) classification, stage, and grade. These results suggest that high expression of α-parvin in stroma is associated with BCs and might be a new predictive marker for diagnosing BC.

Unraveling the Role of PCDH9 in Breast Cancer and Identifying Therapeutic Strategies for PCDH9-Deficient Tumors.

Protocadherin 9 (PCDH9), a member of the cadherin superfamily of transmembrane proteins, plays a role in cell adhesion and neural development. Recent studies suggest that PCDH9 may function as a tumor suppressor in certain cancers, though its specific role in breast cancer remains unclear. UALCAN database to retrieve information on PCDH9 expression in breast cancer tissues compared with that in normal tissues. The biological effects of PCDH9 in breast cancer cells were analyzed using the DepMap database. Stable knockdown or overexpression of PCDH9 in breast cancer cell lines and subsequently assessed tumor cell proliferation and migration. Synthetic lethal screening was conducted for breast cancer cells with low PCDH9 expression or deficiency. In this study, we observed significant downregulation of PCDH9 in breast cancer tissues, with its expression negatively correlated with progression-free survival. Further investigations revealed that decreased PCDH9 expression promotes breast cancer cell proliferation and migration, while overexpression of PCDH9 has the opposite effect. Subsequently, we identified the TAS-102, an approved drug for metastatic colorectal cancer, exhibited selective cytotoxicity against breast cancer cells with low PCDH9 expression. In summary, our study identified PCDH9 as a tumor suppressor in breast cancer and highlighted TAS-102 as a potential therapeutic option for tumors with low PCDH9 expression or deficiency. The specific interaction between TAS-102 and PCDH9 warrants further exploration, providing deeper insights into its mode of action in treating PCDH9-deficient breast cancer.

GFPT1 accelerates immune escape in breast cancer by modifying PD-L1 via O-glycosylation

BackgroundImmune escape is one of the causes of poor prognosis in breast cancer (BC). Glutamine-fructose-6-phosphate transaminase 1 (GFPT1) is the first speed-limiting enzyme of the hexosamine biosynthesis pathway (HBP) and is essential for the progression of BC. Nevertheless, the mechanism of the influence of GFPT1 in BC immune escape is not clear.MethodsFirst, the level of GFPT1 in BC was analyzed by starbase, and GFPT1 expression in BC tissues was measured by qRT-PCR, western blot and IHC. Then, the O-GlcNAc levels were detected by western blot. Thereafter, Co-IP was applied to examine the relationship between GFPT1 and PD-L1. At last, a mouse model was constructed for validation in vivo.ResultsFirstly, we discovered that GFPT1 was obviously strengthened in BC. Knockdown or introduction of GFPT1 correspondingly degraded and elevated O-GlcNAc levels in cells. Further researches revealed that there was a reciprocal relationship between GFPT1 and PD-L1. Mechanistically, we disclosed that GFPT1 enhanced PD-L1 protein stability through O-glycosylation. More interestingly, GFPT1 accelerated BC cell immune escape via upregulation of O-glycosylation-modified PD-L1. In vivo, silencing of GFPT1 attenuated immune escape of BC cells by reducing PD-L1 levels.ConclusionGFPT1 promoted BC progression and immune escape via O-glycosylation-modified PD-L1. GFPT1 may be a potential target for BC therapy.

Trim21-mediated CCT2 ubiquitination suppresses malignant progression and promotes CD4+T cell activation in breast cancer

Breast cancer remains a significant global health challenge, and its mechanisms of progression and metastasis are still not fully understood. In this study, analysis of TCGA and GEO datasets revealed a significant increase in CCT2 expression in breast cancer tissues, which was associated with poor prognosis in breast cancer patients. Functional analysis revealed that CCT2 promoted breast cancer growth and metastasis through activation of the JAK2/STAT3 signaling pathway. Additionally, the E3 ubiquitin ligase Trim21 facilitated CCT2 ubiquitination and degradation, significantly reversing the protumor effects of CCT2. Most interestingly, we discovered that exosomal CCT2 derived from breast cancer cells suppressed the activation and proinflammatory cytokine secretion of CD4+ T cell. Mechanistically, exosomal CCT2 constrained Ca2+-NFAT1 signaling, thereby reducing CD40L expression on CD4+ T cell. These findings highlight CCT2 upregulation as a potential driver of breast cancer progression and immune evasion. Our study provides new insights into the molecular mechanisms underlying breast cancer progression, suggesting that CCT2 is a promising therapeutic target and prognostic predictor for breast cancer.

Development and validation of a neoadjuvant chemotherapy pathological complete remission model based on Reg IV expression in breast cancer tissues: a clinical retrospective study

ObjectiveTo develop and authenticate a neoadjuvant chemotherapy (NACT) pathological complete remission (pCR) model based on the expression of Reg IV within breast cancer tissues with the objective to provide clinical guidance for precise interventions.MethodData relating to 104 patients undergoing NACT were collected. Variables derived from clinical information and pathological characteristics of patients were screened through logistic regression, random forest, and Xgboost methods to formulate predictive models. The validation and comparative assessment of these models were conducted to identify the optimal model, which was then visualized and tested.ResultFollowing the screening of variables and the establishment of multiple models based on these variables, comparative analyses were conducted using receiver operating characteristic (ROC) curves, calibration curves, as well as net reclassification improvement (NRI) and integrated discrimination improvement (IDI). Model 2 emerged as the most optimal, incorporating variables such as HER-2, ER, T-stage, Reg IV, and Treatment, among others. The area under the ROC curve (AUC) for Model 2 in the training dataset and test dataset was 0.837 (0.734–0.941) and 0.897 (0.775–1.00), respectively. Decision curve analysis (DCA) and clinical impact curve (CIC) further underscored the potential applications of the model in guiding clinical interventions for patients.ConclusionThe prediction of NACT pCR efficacy based on the expression of Reg IV in breast cancer tissue appears feasible; however, it requires further validation.

SCARB2 associates with tumor-infiltrating neutrophils and predicts poor prognosis in breast cancer.

The tumor microenvironment (TME) plays a crucial role in various aspects of breast cancer development and metastasis. Nevertheless, the expression, prognostic significance, and correlation with clinical features of SCARB2 in breast cancer, as well as the infiltrative characteristics of TME, remain largely unknown. We analyzed the differential presentation of SCARB2 mRNA in breast cancer tissues and nontumorous breast tissues and prognosis by The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression (GTEx) databases. Additionally, the Tumor Immunity Estimation Resource (TIMER) was taken to evaluate the correlation between SCARB2 mRNA presence and tumor-infiltrating immune cells and immune checkpoints in the TME in breast cancer. We performed multiple immunohistochemical staining to verify the SCARB2 protein expression in breast cancer tissues and its relationship to immune cells and checkpoints and clinicopathological features. We identified elevated SCARB2 expression in breast cancer tissues, and high SCARB2 protein presentation was associated with advanced clinical stage and unfavorable prognosis. In addition, enhanced SCARB2 protein presence was closely correlated with up-regulation CD66b+ neutrophils infiltration in tumor tissues (r = 0.210, P < 0.05) and CD68 + CD163+ M2 macrophages in the interstitium (r = 0.233, P < 0.05), as well as the immune checkpoints, including PD-1 (r = 0.314, P < 0.01) protein expression. SCARB2 holds promise for predicting the clinical outcome of breast cancer patients and could serve as a potential therapeutic target.

SMAD4 depletion contributes to endocrine resistance by integrating ER and ERBB signaling in HR + HER2− breast cancer

Endocrine resistance poses a significant clinical challenge for patients with hormone receptor-positive and human epithelial growth factor receptor 2-negative (HR + HER2−) breast cancer. Dysregulation of estrogen receptor (ER) and ERBB signaling pathways is implicated in resistance development; however, the integration of these pathways remains unclear. While SMAD4 is known to play diverse roles in tumorigenesis, its involvement in endocrine resistance is poorly understood. Here, we investigate the role of SMAD4 in acquired endocrine resistance in HR + HER2− breast cancer. Genome-wide CRISPR screening identifies SMAD4 as a regulator of 4-hydroxytamoxifen (OHT) sensitivity in T47D cells. Clinical data analysis reveals downregulated SMAD4 expression in breast cancer tissues, correlating with poor prognosis. Following endocrine therapy, SMAD4 expression is further suppressed. Functional studies demonstrate that SMAD4 depletion induces endocrine resistance in vitro and in vivo by enhancing ER and ERBB signaling. Concomitant inhibition of ER and ERBB signaling leads to aberrant autophagy activation. Simultaneous inhibition of ER, ERBB, and autophagy pathways synergistically impacts SMAD4-depleted cells. Our findings unveil a mechanism whereby endocrine therapy-induced SMAD4 downregulation drives acquired resistance by integrating ER and ERBB signaling and suggest a rational treatment strategy for endocrine-resistant HR + HER2− breast cancer patients.

The crosstalk between metabolic reprogramming and epithelial-mesenchymal transition and their synergistic roles in distant metastasis in breast cancer.

Metabolic reprogramming (MR) and epithelial-mesenchymal transition (EMT) are crucial phenomena involved in the distant metastasis of breast cancer (BRCA). This study aims to assess the risk of distant metastasis in BRCA patients based on MR and EMT processes and investigate their underlying mechanisms. Gene sets related to EMT and MR were downloaded. MR-related genes (MRG) and EMT-related genes (ERG) were obtained. Principal Component Analysis method was used to define the EMT Potential Index (EPI) and MR Potential Index (MPI) to quantify the EMT and MR levels in each tumor tissue. A linear scoring model, the Metastasis Score, was derived using the union of MRGs and ERGs to evaluate the risk of distant metastasis/recurrence in BRCA. The Metastasis Score was then validated in multiple datasets. Additionally, our study explored the underlying mechanism of the Metastasis Score and its association with tumor immunity, focusing on HPRT1 gene expression in breast cancer tissues of transfer and untransferred groups using experimental methods. A total of 59 MRGs and 30 ERGs were identified in the present study. Stratifying the dataset based on EPI and MPI revealed significantly lower survival rates (P < .05) in the MPI_high and EPI_high groups. Kaplan-Meier analysis indicated the lowest survival rate in the EPI-high + MPI-high group. The Metastasis Score demonstrated its ability to distinguish prognoses in GSE2034, GSE17705, and TCGA-BRCA datasets. Additionally, differences in mutated genes were found between the high- and the low-Metastasis Score groups, displaying significant associations with immune cell infiltration and anti-tumor immune status. Notably, the 13 genes included in the Metastasis Score showed a strong association with prognosis and tumor immunity. Immunohistochemistry and western blot results revealed high expression of the HPRT1 gene in the transfer group. This study established the Metastasis Score as a reliable tool for evaluating the risk of distant metastasis/recurrence in BRCA patients. Additionally, we identified key genes involved in MR and EMT crosstalk, offering valuable insights into their roles in tumor immunity and other relevant aspects.

IFI30 as a key regulator of PDL1 immunotherapy prognosis in breast cancer

BackgroundIFI30 is a lysosomal thiol reductase involved in antigen presentation and immune regulation in various cancers, including breast cancer. Despite its known involvement, the precise mechanism, function, and relationship with the PD-L1 axis and immune response remain unclear. MethodsWe conducted an extensive investigation into IFI30 mRNA expression in breast cancer utilizing data from The Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases. Furthermore, we characterized IFI30 mRNA expression across various cell types using publicly available single-cell RNA sequencing datasets, and assessed protein expression through immunohistochemistry using an in-house breast cancer tissue microarray. Functional experiments were performed to elucidate the effects of IFI30 overexpression on PD-L1 expression and inhibitory efficacy in both macrophages and breast tumor cells. ResultsOur study unveiled a marked upregulation of IFI30 expression in breast cancer tissues compared to their normal counterparts, with notable associations identified with tumor stage and prognosis. Additionally, IFI30 expression demonstrated significant correlations with various immune-related signaling pathways, encompassing peptide antigen binding, cytokine binding, and MHC class II presentation. Notably, breast cancer samples exhibiting high IFI30 expression in tumor cells displayed high PD-L1 expression on corresponding cells, alongside a diminished ratio of CD8 + T cell infiltration within the tumor microenvironment. Furthermore, ectopic knockdown of IFI30 in both tumor cells and macrophages resulted in a reduction of PD-L1 expression, while conversely, overexpression of IFI30 led to an increase in PD-L1 expression. ConclusionsThis study offers new insights into the involvement of IFI30 in breast cancer, elucidating its interplay with the PD-L1 axis and immune response dynamics. Our findings suggest that modulation of the IFI30-PD-L1 axis could serve as a promising strategy for regulating T cells infiltration in breast cancer thus treating breast cancer.

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.

The evaluation of human endogenous retroviral env expression in normal and cancerous tissues of the breast

Abstract Background: Both internal and external risk factors can accelerate the progression of breast cancer which is the reason why clinicians have tried to find new biomarkers for this health problem. Human endogenous retrovirus-W (HERV-W) can be one of these biomarkers, as it has been mentioned that some genes of this virus are able to have either higher or lower expression in numerous cancerous cells. In this study, we aimed to compare HERV-W envelope expression in breast cancer tissues and normal ones since its effects on this malignancy have not been clear. Materials and Methods: We collected 46 breast cancer tissues and their normal adjacent ones. After extracting the RNA of breast samples, we evaluated the expression of HERV-W envelope syncytin-1 and 2 using quantitative real-time polymerase chain reaction (PCR) in different kinds of breast cancer stages. Results: Data showed that more than 13% of patients had a family history of breast cancer; moreover, approximately half of the tissues were estrogen receptor or progesterone receptor positive. Lymph node metastasis was seen in 52% of the patients, and about 40% of tumors were larger than 2 cm. Real-time PCR showed that syncytin-1 and 2 had upward regulation with (*P &lt; 0.05) and (**P &lt; 0.01), respectively. Conclusion: As the expression of HERV-W Env (syncytin-1, syncytin-2) was higher in breast cancerous tissues in comparison with normal ones, we believe that these genes may have a role to play in monitoring patients suffering from this type of cancer. However, further studies are needed to confirm this hypothesis.

A novel long non-coding RNA LINC00524 facilitates invasion and metastasis through interaction with TDP43 in breast cancer.

Breast cancer (BC) remains a significant health concern worldwide, with metastasis being a primary contributor to patient mortality. While advances in understanding the disease's progression continue, the underlying mechanisms, particularly the roles of long non-coding RNAs (lncRNAs), are not fully deciphered. In this study, we examined the influence of the lncRNA LINC00524 on BC invasion and metastasis. Through meticulous analyses of TCGA and GEO data sets, we observed a conspicuous elevation of LINC00524 expression in BC tissues. This increased expression correlated strongly with a poorer prognosis for BC patients. A detailed Gene Ontology analysis suggested that LINC00524 likely exerts its effects through RNA-binding proteins (RBPs) mechanisms. Experimentally, LINC00524 was demonstrated to amplify BC cell migration, invasion and proliferation invitro. Additionally, invivo tests showed its potent role in promoting BC cell growth and metastasis. A pivotal discovery was LINC00524's interaction with TDP43, which leads to the stabilization of TDP43 protein expression, an element associated with unfavourable BC outcomes. In essence, our comprehensive study illuminates how LINC00524 accelerates BC invasion and metastasis by binding to TDP43, presenting potential avenues for therapeutic interventions.

Osteopontin promotes tumor growth and metastasis and GPX4-mediated anti-lipid peroxidation in triple-negative breast cancer by activating the PI3k/Akt/mTOR pathway

PurposeTriple-negative breast cancer (TNBC) features high aggressiveness, metastasis rate, drug resistance as well as poor prognosis. Osteopontin (OPN) is a key protein in the process of osteogenesis and has emerged as a new tumor marker in recent years.MethodsCell viability was tested with the CCK-8 kit. Transwell and wound healing were adopted to test cell invasive and migratory abilities. Tumor sphere formation was detected by tumor sphere formation assay. Human umbilical vein endothelial cell (HUVEC) tube formation assay was used to measure the angiogenesis of tumor cells. Western blot was applied for the estimation of the expression of cancer stem cell markers, angiogenesis-, signaling pathway-related proteins as well as OPN. Bioinformatics tools predicted OPN expression in breast cancer tissues. The levels of oxidative stress-related markers were assessed with ELISA. Following the overexpression of OPN in MD-MB-436 cells and the addition of the PI3K/AKT/mTOR pathway inhibitor LY294002, the aforementioned functional experiments were implemented again to investigate the mechanism. Finally, in vivo experiments of tumor-bearing mice were performed for further verification. ResultsThe proliferative, invasive, migratory and tumor sphere formation capabilities as well as angiogenesis of TNBC cells were conspicuously increased in contrast to non-TNBC cell lines. OPN expression in TNBC tissues and cells was dramatically enhanced. OPN upregulation significantly elevated cell proliferative, invasive and migratory capabilities as well as tumor sphere formation and angiogenesis. The mechanism might be achieved by activating PI3K/AKT/mTOR signaling to regulate glutathione peroxidase 4 (GPX4)-mediated anti-lipid peroxidation.ConclusionOPN promoted tumor sphere formation and angiogenesis in TNBC by activating the PI3K/AKT/mTOR pathway to regulate GPX4-mediated anti-lipid peroxidation levels.

Abstract 7220: Emerging combination strategy: FANCI suppression induces PARP1 redistribution to enhance efficacy of PARP inhibitors in breast cancer

Abstract While polyADP-ribose polymerase (PARP) inhibitors have made advancements in the treatment of breast cancer, challenges such as chemotherapy resistance and limited application persist. Fanconi AnemiaComplementation Group I (FANCI), a DNA repair protein associated with breast cancer development, represents a potential target for novel combination therapeutic strategies. However, the role of FANCI in breast cancer and its impact on the efficacy of PARP inhibitors require further investigation. In our study, we analyzed FANCI expression in breast cancer tissues and cell lines, and its correlation with clinical parameters and patient prognosis. Lentiviral vectors were utilized and functional assays were performed to evaluate the effects of FANCI modulation on breast cancer cell growth and migration. Co-immunoprecipitation assays and protein interaction analysis were conducted to identify the interaction between FANCI and PARP1 and determine the specific binding region. The functionality and nuclear distribution of PARP1 were assessed upon FANCI modulation. Finally, the sensitivity of breast cancer cells to the PARP inhibitor talazoparib upon FANCI knockdown was evaluated in vitro and in vivo. Our findings demonstrated that FANCI was overexpressed in breast cancer and associated with poor prognosis. FANCI significantly promoted breast cancer cell proliferation both in vitro and in vivo. We identified the interaction between FANCI and PARP1, specifically at the FANCI helical domain 2 binding site. FANCI knockdown led to reduced nuclear localization of PARP1 and decreased PARP1 activity. Importantly, combination treatment with FANCI knockdown and talazoparib significantly inhibited cancer growth in vitro and in vivo. Additionally, we found that the cyclin-dependent kinase (CDK) 4/6 inhibitor palbociclib, which effectively suppresses FANCI protein expression, exhibited a robust synergistic effect with talazoparib both in vitro and in vivo. In conclusion, FANCI is a novel therapeutic target for breast cancer. Suppression of FANCI regulates PARP1 redistribution and activity, making breast cancer cells more responsive to PARP inhibitors. This combination therapeutic strategy shows potential in enhancing the effectiveness of PARP inhibitors for breast cancer treatment, regardless of BRCA mutations. Citation Format: Yu-zhou Huang, Ming-Yi Sang, Pei-Wen Xi, Ruo-Xi Xu, Meng-Yuan Cai, Zi-Wen Wang, Jian-Yi Zhao, Yi-Han Li, Ji-Fu Wei, Qiang Ding. Emerging combination strategy: FANCI suppression induces PARP1 redistribution to enhance efficacy of PARP inhibitors in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7220.

Exploring CCL11 in breast cancer: unraveling its anticancer potential and immune modulatory effects involving the Akt-S6 signaling

BackgroundCCL11, a chemokine known for recruiting immune cells to the tumor microenvironment (TME), has an unclear role in the context of its expression, patient prognosis, and the presence of tumor-infiltrating immune cells (TILs) in breast cancer.MethodsThe expression of CCL11 in invasive breast cancer (BRCA) was analyzed using TCGA database. Survival curve and Cox regression analysis determined the potential of CCL11 as an independent prognostic indicator. GSEA performed functional analysis on genes related to CCL11. CIBERSORT algorithm quantified the infiltration level of immune cells with varying CCL11 expression. Lastly, the correlation between CCL11 expression and anticancer drug sensitivity was examined. Immunohistochemistry (IHC) and qRT-PCR confirmed CCL11 expression in clinical tissue samples. The anti-tumor efficacy of CCL11 was investigated using CCK-8, plate formation, transwell assay, and Western blot.ResultsCCL11 expression was elevated in BRCA tumor tissues compared to adjacent normal tissues. Recurrence-free survival (RFS) was longer in patients with high expression of CCL11. Enrichment and co-expression analyses revealed CCL11's association with numerous immune-related signaling pathways and genes. Validation studies confirmed high CCL11 expression in breast cancer tissues. In vitro experiments substantiated CCL11's anticancer effects in BRCA.ConclusionCCL11 expression correlates with immune cell infiltration in breast cancer, indicating its potential as a prognostic biomarker for BRCA.

Increased SLC7A3 Expression inhibits Tumor Cell Proliferation and Predicts a Favorable Prognosis in Breast Cancer.

Arginine plays significant and contrasting roles in breast cancer growth and survival. However, the factors governing arginine balance remain poorly characterized. We aimed to identify the molecule that governs arginine metabolism in breast cancer and to elucidate its significance. We analyzed the correlation between the expression of solute carrier family 7 member 3 (SLC7A3), the major arginine transporter, and breast cancer survival in various databases, including GEPIA, UALCAN, Metascape, String, Oncomine, KM-plotter, CBioPortal and Prognosis. Additionally, we validated our findings through bioinformatic analyses and experimental investigations, including colony formation, wound healing, transwell, and mammosphere formation assays. Our analysis revealed a significant reduction in SLC7A3 expression in all breast cancer subtypes compared to adjacent breast tissues. Kaplan-Meier survival analyses demonstrated that high SLC7A3 expression was positively associated with decreased nodal metastasis (HR=0.70, 95% CI [0.55, 0.89]), ER positivity (HR=0.79, 95% CI [0.65, 0.95]), and HER2 negativity (HR=0.69, 95% CI [0.58, 0.82]), and increased recurrence-free survival. Moreover, low SLC7A3 expression predicted poor prognosis in breast cancer patients for overall survival. Additionally, the knockdown of SLC7A3 in MCF-7 and MDA-MB-231 cells resulted in increased cell proliferation and invasion in vitro. Our findings indicate a downregulation of SLC7A3 expression in breast cancer tissues compared to adjacent breast tissues. High SLC7A3 expression could serve as a prognostic indicator for favorable outcomes in breast cancer patients due to its inhibitory effects on breast cancer cell proliferation and invasion.

Upregulated SAE1 Drives Tumorigenesis and Is Associated with Poor Clinical Outcomes in Breast Cancer

Background. The purpose of this study was to analyze SUMO activating enzyme subunit 1 (SAE1) expression in breast cancer (BC). Through bioinformatics analysis and in vitro experiments, the biological function and possibly associated signal pathways of SAE1 in BC were further analyzed. Methods. Bioinformatics analysis was applied to analyze SAE1 expression in BC and normal breast tissues, its relationship with clinicopathologic characteristics and prognosis in BC patients, and data from the Cancer Genome Atlas database and Gene Expression Omnibus dataset. We performed immunohistochemistry to analyze SAE1 expression in BC tissues and para‐cancer tissues in 79 breast cancer patients. BC cell proliferation was detected with the Cell Counting Kit‐8 and by the colony formation assay. Cell cycle progression was analyzed by flow cytometry, and the expression of cell cycle‐related proteins (E2F1, cyclin D3, and cyclin‐dependent kinase 2) was determined by western blots in SAE1 small interfering RNA (siRNA) transfected cells. The GSE1456 dataset was used to analyze possible signal pathways associated with SAE1 by gene set enrichment analysis (GSEA), and the expression of PI3K/AKT/mTOR pathway‐related proteins (such as p‐PI3K, p‐AKT, and mTOR) in SAE1‐siRNA cells was detected by western blots. Results. The bioinformatics and immunohistochemical results showed that SAE1 mRNA and protein expression in BC tissues were significantly higher than those in normal tissues. The SAE1 overexpression was significantly associated with the tumor size, tumor‐node‐metastasis stage, estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2, and whether or not it was a triple‐negative BC. Patients with SAE1 overexpression had a worse overall survival (OS), recurrence‐free survival (RFS), and distant metastasis‐free survival compared with lower expression patients. Multivariate Cox regression analysis showed that SAE1 may be an independent prognostic factor for OS of BC patients. The proliferation and cell cycle process of BC cells were inhibited by SAE1‐siRNA in vitro. The result of GSEA showed that SAE1 was significantly associated with 12 gene sets, including unfolded protein reaction, DNA repair, oxidative phosphorylation, and cell cycle, among others. Additionally, two signal pathways, mTORC1 and PI3K/Akt/mTOR, were significantly correlated with SAE1 overexpression. Western blots confirmed that the expression of PI3K/Akt/mTOR pathway‐related proteins (p‐PI3K, p‐AKT, and mTOR) in BC cells was decreased after knocking down SAE1. Conclusion. SAE1 was highly expressed in BC. Its overexpression was associated with poor BC prognosis. Additionally, it was an independent prognostic factor for BC patients. We demonstrated that in vitro SAE1 knockdown effectively inhibited BC proliferation and its cell cycle process. Furthermore, the biological function of SAE1 may be associated with the PI3K/Akt/mTOR pathway. SAE1 will be a potential target for BC treatment.

Upregulation of ZMAT3 is Associated with the Poor Prognosis of Breast Cancer.

Breast cancer is the leading cause of cancer-related deaths among women worldwide. Identifying robust biomarkers for predicting outcomes is essential for improving patient care and reducing fatalities. ZMAT3, a zinc finger protein with potential carcinogenic properties, has been associated with various cancers. However, its role in breast cancer prognosis remains unclear. We investigated the expression level of ZMAT3 in breast cancer tissues and its association with clinical outcomes through bioinformatics analysis and experimental validation. We examined the correlation between ZMAT3 expression and immune characteristics. ZMAT3 mRNA expression data from The Cancer Genome Atlas (TCGA) were analysed in relation to overall survival (OS), disease-specific survival (DSS) and progression-free interval (PFI) in patients with breast cancer. Immunohistochemistry (IHC) was performed on breast cancer tissues to assess ZMAT3 protein levels, with findings validated using qPCR and cell experiments. ZMAT3 mRNA levels were significantly upregulated in breast cancer samples compared to normal tissues. High ZMAT3 expression was significantly correlated with the poor OS, DSS and PFI. A significant positive correlation was observed between high ZMAT3 mRNA levels and the abundance of tumour-infiltrating lymphocytes (TILs), especially CD8+T cells and regulatory T cells (Tregs). Multivariate Cox regression analysis identified ZMAT3 as an independent prognostic factor for breast cancer. IHC staining confirmed increased ZMAT3 protein expression in breast cancer tissues, which was further validated by qPCR and cell function tests. Our findings suggest that ZMAT3 is a prognostic biomarker linked to immune invasion in breast cancer. Elevated ZMAT3 expression correlates with adverse clinical outcomes, indicating its potential role in disease progression.

A new clinical prognosis model for breast cancer with ADSS as the hub gene.

Background: Breast cancer (BRCA) is the most common malignant tumor and the leading cause of cancer death worldwide. Adenylosuccinate synthetase (ADSS) is highly expressed in BRCA and its subtypes malignant tumors and is associated with poor prognosis. Methods: By applying ROC curve, survival analysis, WGCNA, enrichment analysis, Cox regression model and other methods, this study explores the role of ADSS in BRCA and constructs a scoring model. Results: In this study, the ADSS demonstrated good diagnostic efficacy and high expression in breast cancer tissues. Further exploration of the role of ADSS in BRCA revealed that its significantly related coexpressed genes are clearly involved in biological functions and signaling pathways associated with cell proliferation and differentiation. Additionally, the ADSS-related scoring model showed a significant prognostic impact on clinical characteristics, such as metastasis to lymph nodes, and it was discovered that the ADSS score and related scoring genes may affect the immune microenvironment of BRCA patients, potentially participating in the occurrence of this disease. Conclusion: In summary, our gene expression analysis of ADSS in BRCA generated a clinical scoring model based on the ADSS that may be used to assess prognostic risk and provide potential clinical applications and rational therapeutic targets.