Advances in immunotherapy for triple-negative breast cancer

The role of ferroptosis in breast cancer: Tumor progression, immune microenvironment interactions and therapeutic interventions

Ferroptosis represents a distinctive and distinct form of regulated cellular death, which is driven by the accumulation of lipid peroxidation. It is distinguished by altered redox lipid metabolism and is linked to a spectrum of cellular activities, including cancer. In breast cancer (BC), with triple negative breast cancer (TNBC) being an iron-and lipid-rich tumor, inducing ferroptosis was thought to be a novel approach to killing breast tumor cells. However, in the recent past, a novel conceptual framework has emerged which posits that in addition to the promotion of tumor cell death, ferritin deposition has a potent immunosuppressive effect on the tumor immune microenvironment (TIME) via the influence on both innate and adaptive immune responses. TIME of BC includes various cell populations from both the innate and adaptive immune systems. In this review, the internal association between iron homeostasis and the progression of ferroptosis, along with the common inducers and protectors of ferroptosis in BC, are discussed in detail. Furthermore, a comprehensive analysis is conducted on the dual role of ferroptosis in immune cells and proto-oncogenic functions, along with an evaluation of the potential applications of immunogenic cell death-targeted immunotherapy in TIME of BC. It is anticipated that our review will inform future research endeavors that seek to integrate ferroptosis and immunotherapy in the management of BC.

A mitochondria-interfering nanocomplex cooperates with photodynamic therapy to boost antitumor immunity

Immunotherapeutics against triple-negative breast cancer (TNBC) hold great promise. In this work, we provide a combination therapy for simultaneous increasing tumor immunogenicity and down-regulating programmed cell death ligand 1 (PD-L1) to boost antitumor immunity in TNBC. We prepare bis (diethyldithiocarbamate)-copper/indocyanine green nanoparticles (CuET/ICG NPs) simply in aqueous with one-pot method. CuET/ICG NPs interfere mitochondria, reduce oxygen consumption, and alleviate tumor hypoxia to potentiate photodynamic therapy (PDT) for amplifying immunogenic cell death (ICD). Meanwhile, mitochondria dysfunction leads to energy stress and activates AMPK pathway. As a result, CuET/ICG NPs downregulates membrane PD-L1 (mPD-L1) on both 4T1 cancer cells and cancer stem cells (CSCs) through AMP-activated protein kinase (AMPK)-mediated pathway in hypoxia. Cooperatively, the combinational therapy activates antitumor immunity and triggers long lasting immune memory response to resist tumor re-challenge. Our study represents an attempt that conquers tumor immunosuppressive microenvironment with simple biomedical materials and multimodality treatments.

The combination of flaxseed lignans and PD-1/ PD-L1 inhibitor inhibits breast cancer growth via modulating gut microbiome and host immunity

BACKGROUND

Patients with breast cancer (BC) who benefit from the PD-1/PD-L1 inhibitor (PDi) is limited, necessitating novel strategies to improve immunotherapy efficacy of BC. Here we aimed to investigate the inhibitory effects of flaxseed lignans (FL) on the biological behaviors of BC and evaluate the roles of FL in enhancing the anticancer effects of PDi.

METHODS

HPLC was used to detect the content of enterolactone (ENL), the bacterial transformation product of FL. Transcript sequencing was performed and identified CD38 as a downstream target gene of ENL. CD38-overexpressing cells were constructed and cell proliferation, colony formation, wound healing and transwell assays were used to assess the function of ENL/CD38 axis on BC cells in vitro. Multiplexed immunohistochemistry (mIHC) and CyTOF were used to detect the changes of the tumor immune microenvironment (TIM). 16S rDNA sequencing was used to explore the changes of gut microbiota in mice. A series of in vivo experiments were conducted to investigate the anticancer effects and mechanisms of FL and PDi.

RESULTS

FL was converted to ENL by gut microbiota and FL administration inhibited the progression of BC. ENL inhibited the malignant behaviors of BC by downregulating CD38, a key gene associated with immunosuppression and PD-1/PD-L1 blockade resistance. The mIHC assay revealed that FL administration enhanced CD3+, CD4+ and CD8+ cells and reduced F4/80+ cells in TIM. CyTOF confirmed the regulatory effects of FL and FL in combination with PDi (FLcPDi) on TIM. In addition, 16S rDNA analysis demonstrated that FLcPDi treatment significantly elevated the abundance of Akkermansia and, importantly, Akkermansia administration enhanced the response to PDi in mice treated with antibiotics.

CONCLUSIONS

The FL/ENL/CD38 axis inhibited BC progression. FL enhanced the anticancer effects of PDi by modulating gut microbiota and host immunity.

Photodynamic Biomimetic Liposomes Targeted to the Endoplasmic Reticulum Enhance Combined Immunotherapy for Triple-Negative Breast Cancer

Cancer immunotherapies, such as immune checkpoint inhibitors, have advanced rapidly and achieved notable success, yet they face significant challenges due to poor response rates and immune-related adverse effects, particularly in cases of triple-negative breast cancer (TNBC). Photodynamic therapy (PDT) can initiate immunogenic cell death (ICD) by inducing endoplasmic reticulum (ER) stress, thereby enhancing the effectiveness of tumor immunotherapy. Herein, we develop potent PDT biomimetic liposomes (PB Lipo) locating the ER to realize a synergistic immuno-photodynamic treatment. The PB Lipo is prepared using the optimal ratios of the phospholipids in the ER membrane. It is then loaded with indocyanine green (ICG), a photosensitizer approved for clinical use. PB Lipo has the unique ability to accumulate in the ER via membrane fusion, leading to severe ER stress when exposed to near-infrared (NIR) laser light, thus intensifying ICD. In combination with the antiprogrammed death-ligand 1 (PD-L1) antibody (αPD-L1), PB Lipo significantly improves efficiency against tumors in xenograft TNBC models. As a result, our combined treatment enhances mature dendritic cells, activates CD4+ T and CD8+ T cells, and promotes the secretion of cytotoxic cytokines. Collectively, our findings reveal that PB Lipo-mediated PDT presents a viable approach for effectively targeting the ER and enhancing ICD, thereby boosting antitumor efficacy in TNBC.

Targeting matrix metalloproteinases activating and Indoleamine 2,3-dioxygenase suppression for triple-negative breast Cancer multimodal therapy

The dense extracellular matrix (ECM) and immunosuppressive tumor microenvironment represent two major challenges in the treatment of triple-negative breast cancer (TNBC). To address these obstacles, this study has developed a polymer micelle (NTP) for ECM remodeling and mitigation the immune microenvironment, based on activating endogenous matrix metalloproteinases (MMP) and suppression indoleamine 2,3-dioxygenase (IDO). Through self-assembly technology, this micelle effectively incorporates chemotherapy drugs (camptothecin (CPT) and cinnamaldehyde (CA)), reactive oxygen species (ROS) stimulants, nitric oxide (NO) donor and IDO inhibitor (NLG919), where CPT and CA have been reported to help generating ROS mainly in the mitochondrion. The guanidine group of poly-L-arginine (PArg), as an NO donor, can react with ROS to generate NO. The micelles aim to achieve significant therapeutic outcomes through robust drug penetration and anti-tumor immunity in multimodal therapy. They exhibit remarkable tumor tissue penetration ability, facilitating precise targeting of mitochondria and ROS production stimulation. Building upon this therapeutic foundation, the micellar system achieves in situ NO release, which effectively degrades the primary ECM through the activation of MMPs, while simultaneously promoting tumor cell apoptosis. Furthermore, the encapsulated NLG919 can be released and effectively mitigating the immunosuppressive milieu and triggering anti-tumor immune responses. Experimental results demonstrate that the micelles exhibit significant anti-tumor effects both in vitro and in vivo, accompanied by favorable biocompatibility. This study provides new insights into the application of subcellular targeting drug delivery systems in TNBC treatment, potentially heralding a new breakthrough in TNBC therapy.

Tumor vascular normalization by B7-H3 blockade augments T lymphocyte-mediated antitumor immunity

Triple-negative breast cancer (TNBC), defined by the absence of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), presents unique clinical challenges and generally predicts a less favorable prognosis. Despite recent advancements in TNBC treatment, a subset of patients remains resistant to immunotherapy. B7-H3, a member of the B7 family of immune checkpoints, is correlated with poor outcomes in various cancers and is distinctively expressed in tumor vasculature, marking it as a potential biomarker for tumor-associated endothelial cells. We found high expression of B7-H3 in the endothelial cells of the postoperative tissue of TNBC patients. Elevated gene expression of CD276 (encoding B7-H3) and PECAM1 (encoding CD31) in TNBC is associated with poor prognosis. Anti-B7-H3 blockade reduces tumor burden and promotes lymphocyte infiltration in a TNBC mouse model. Additionally, anti-B7-H3 blockade promotes tumor vessel normalization and enhances programmed cell death ligand 1 (PD-L1) expression. Synergistic effects were observed when B7-H3 blockade was combined with programmed cell death protein 1 (PD-1) inhibition in the TNBC mouse model. Furthermore, anti-B7-H3 inhibits human umbilical vein endothelial cell (HUVEC) proliferation by suppression of the nuclear factor kappa-B (NF-κB) signaling pathway. Downregulation of B7-H3 expression in HUVECs promotes lymphocyte trans-endothelial migration. These findings suggest that B7-H3 represents a promising therapeutic target for TNBC, and the combination of anti-B7-H3 and anti-PD-1 therapies may have synergetic effects in treating TNBC.

MGAT1-Guided complex N-Glycans on CD73 regulate immune evasion in triple-negative breast cancer

Despite the widespread application of immunotherapy, treating immune-cold tumors remains a significant challenge in cancer therapy. Using multiomic spatial analyses and experimental validation, we identify MGAT1, a glycosyltransferase, as a pivotal factor governing tumor immune response. Overexpression of MGAT1 leads to immune evasion due to aberrant elevation of CD73 membrane translocation, which suppresses CD8+ T cell function, especially in immune-cold triple-negative breast cancer (TNBC). Mechanistically, addition of N-acetylglucosamine to CD73 by MGAT1 enables the CD73 dimerization necessary for CD73 loading onto VAMP3, ensuring membrane fusion. We further show that THBS1 is an upstream etiological factor orchestrating the MGAT1-CD73-VAMP3-adenosine axis in suppressing CD8+ T cell antitumor activity. Spatial transcriptomic profiling reveals spatially resolved features of interacting malignant and immune cells pertaining to expression levels of MGAT1 and CD73. In preclinical models of TNBC, W-GTF01, an inhibitor specifically blocked the MGAT1-catalyzed CD73 glycosylation, sensitizing refractory tumors to anti-PD-L1 therapy via restoring capacity to elicit a CD8+ IFNγ-producing T cell response. Collectively, our findings uncover a strategy for targeting the immunosuppressive molecule CD73 by inhibiting MGAT1.

Evaluation of the impact of miR-3143 on the PI3K/AKT signaling pathway and its subsequent influence on the metastatic phenotype of triple-negative breast cancer cells

MicroRNAs (miRNAs) are recognized to have a pivotal role in the progression and metastatic dissemination encompassing diverse cancer varieties, such as triple-negative breast cancer (TNBC). Recent evidence has suggested that specific miRNA species can directly or indirectly influence the onset, progression, and relapse of TNBC. Previous studies have reported the frequent reduction of miR-3143 in TNBC, which appears to coincide with the activation of proliferative signaling pathways. However, the potential restorative effects of miR-3143 on TNBC cellular behavior remain unexplored. In the present study, we utilized exosome-mediated delivery to introduce miR-3143 into TNBC cells and investigated its impact on the PI3K/AKT pathway and the resulting effects on cellular proliferation, movement, and apoptosis. MDA-MB-231 TNBC cells underwent treatment with miR-3143-electroporated human umbilical cord mesenchymal stem cell (HUCMSC)-derived exosomes. RT-qPCR analysis was utilized to assess the influence of miR-3143 overexpression on the expression of its target genes, PIK3CA and AKT1, which was further validated through dual-luciferase reporter assays. Our results demonstrated that the overexpression of miR-3143 could effectively decline the level of AKT1 and PIK3CA by directly binding to their 3'-UTRs. Furthermore, the introduction of miR-3143 into TNBC cells resulted in a significant enhancement of apoptotic activities. Interestingly, the delivery of miR-3143 via HUCMSC-derived exosomes could inhibit the protumorigenic and prometastatic behaviors of TNBC cells, potentially limiting their malignant progression. Collectively, these findings enhance comprehension of the regulatory mechanisms by which miR-3143 can modulate the metastatic potential of TNBC cells. The insights gained from this study may facilitate the creation of innovative miRNA-targeting approaches to combat the aggressive nature of TNBC andstrengthen treatment effectiveness.

Cost-effectiveness analysis of toripalimab combined with nab-paclitaxel as a first-line treatment for advanced TNBC in the US

INTRODUCTION

Initial immunotherapy outcomes with toripalimab suggest a potential paradigm shift in the treatment of advanced triple-negative breast cancer (TNBC), promising extended survival for patients. However, its cost-effectiveness in the treatment of TNBC within the US health care context remains to be determined.

METHODS

A 5-year Markov model was developed using data from the TORCHLIGHT study to evaluate the cost-effectiveness of toripalimab plus nab-paclitaxel as a first-line therapy for metastatic or recurrent TNBC in the US. The model incorporated efficacy and safety data, literature-derived costs and utilities, and calculated ICERs. Sensitivity analyses were conducted to assess the impact of variable uncertainties on the outcomes.

RESULTS

Toripalimab combined with nab-P chemotherapy for TNBC patients resulted in an additional 2.68 life years (LYs) and 1.72 quality-adjusted life years (QALYs), with an ICER of $593,750 per QALY. Sensitivity analyses indicated that the cost and survival utility of toripalimab significantly influence patient outcomes. At a $100,000/QALY WTP threshold, combination therapy was not cost-effective compared with nab-P alone.

CONCLUSIONS

Our analysis suggests that, from a US health care system perspective, toripalimab in combination with chemotherapy does not demonstrate a significant cost-effective advantage over nab-P chemotherapy as a first-line treatment for patients with TNBC at a WTP threshold of $100,000/QALY and has a limited impact on US health care policy and clinical practice.

Bimetallic chitosan/hyaluronic acid nanoparticles self-amplify ferroptosis/cuproptosis in triple-negative breast cancer

As a notoriously incurable tumor, triple-negative breast cancer (TNBC) exhibits significant sensitivity to ferroptosis and the glutathione (GSH) antioxidant defense system plays a crucial role in its progression. Herein, we report a bimetallic chitosan/hyaluronic acid nanoparticle (5FCN, with a Fe/Cu mass ratio of 5:5) that employs a self-amplified dual mechanism of ferroptosis and cuproptosis for TNBC therapy. Hyaluronic acid in 5FCN specifically binds to the overexpressed CD44 receptor on TNBC cells. This allows 5FCN to enter cells via receptor-mediated endocytosis, then release metal ions in acidic environments. Released Fe3+ and Cu2+ react with GSH in tumor cells, weakening the antioxidant system and producing Fe2+ and Cu+. These ions trigger Fenton/Fenton-like reactions with H2O2, generating toxic hydroxyl radicals (·OH) to boost ferroptosis. Meanwhile, high-valent Cu2+ and Fe3+ are produced, forming a cycle for GSH depletion and ·OH generation. As H2O2 depletes, the rising Cu+ level in cells causes lipoylated protein aggregation, amplifying cuproptosis. In vitro and in vivo studies demonstrated that 5FCN exhibited superior cell-killing efficacy against TNBC with few side effects. Collectively, 5FCN represents a potential drug to self-amplify ferroptosis/cuproptosis in TNBC.

Exosome-Mediated Cellular Communication in the Tumor Microenvironment Imparts Drug Resistance in Breast Cancer

Globally, breast cancer (BC) is the leading cause of cancer-related death for women. BC is characterized by heterogeneity, aggressive behavior, and high metastatic potential. Chemotherapy, administered as monotherapy or adjuvant therapy, remains a cornerstone of treatment; however, acquired drug resistance is a significant clinical challenge. Deciphering mechanisms of drug resistance will be central to developing more efficient treatment options and improving patient outcomes. The current review examines the multifaceted nature of exosomes in conferring drug resistance in BC through complex communication networks within the tumor microenvironment. We further explore recent advances in understanding how exosomes contribute to resistance against established chemotherapeutic agents such as tamoxifen, paclitaxel, doxorubicin, platinum-based drugs, trastuzumab, and newer immunotherapies, such as immune checkpoint inhibitors. Moreover, we discuss existing systematic approaches to investigating the exosome-drug resistance relationship in BC. Finally, we explore promising therapeutic approaches to overcome exosome-dependent drug resistance in BC, highlighting potential avenues for improved treatment efficacy. Investigating the distinct functions and cargo of exosomes offers potential for developing innovative approaches to overcoming treatment resistance.

Molecular Subtypes and Mechanisms of Breast Cancer: Precision Medicine Approaches for Targeted Therapies

Breast cancer remains one of the most prevalent diseases worldwide, primarily affecting women. Its heterogeneous nature poses a significant challenge in the development of effective and targeted treatments. Molecular characterization has enabled breast cancer to be classified into four main subtypes: luminal A, luminal B, HER2-positive, and triple-negative breast cancer, based on hormone receptor expression and HER2 status. A deeper understanding of these molecular markers and their associated signaling pathways, such as MAPK and PI3K/AKT, is essential for improving prognosis and optimizing treatment strategies. Currently, several therapeutic agents are utilized in neoadjuvant and adjuvant therapies, often in combination with surgical interventions. However, emerging evidence highlights the growing challenge of drug resistance, which significantly limits the efficacy of existing treatments. Addressing this issue may require innovative approaches, including combination therapies and precision medicine strategies, tailored to the molecular profile of each patient. Therefore, a comprehensive understanding of the pathophysiologic mechanisms driving breast cancer progression and resistance is crucial for the development of advanced targeted therapies with greater precision and efficacy. This review aims to explore recent advancements in molecular research related to breast cancer subtypes and provide a critical analysis of current therapeutic approaches within the framework of precision medicine.

Genetically engineered macrophages reverse the immunosuppressive tumor microenvironment and improve immunotherapeutic efficacy in TNBC

The main challenges in current immunotherapy for triple-negative breast cancer (TNBC) lie in the immunosuppressive tumor microenvironment (TME). Considering tumor-associated macrophages (TAMs) are the most abundant immune cells in the TME, resetting TAMs is a promising strategy for ameliorating the immunosuppressive TME. Here, we developed genetically engineered macrophages (GEMs) with gene-carrying adenoviruses, to maintain the M1-like phenotype and directly deliver the immune regulators interleukin-12 and CXCL9 into local tumors, thereby reversing the immunosuppressive TME. In tumor-bearing mice, GEMs demonstrated targeted enrichment in tumors and successfully reprogramed TAMs to M1-like macrophages. Moreover, GEMs significantly enhanced the accumulation, proliferation, and activation of CD8+ T cells, mature dendritic cells, and natural killer cells within tumors, while diminishing M2-like macrophages, immunosuppressive myeloid-derived suppressor cells, and regulatory T cells. This treatment efficiently suppressed tumor growth. In addition, combination therapy with GEMs and anti-programmed cell death protein 1 further improved interferon-γ+CD8+ T cell percentages and tumor inhibition efficacy in an orthotopic murine TNBC model. Therefore, this study provides a novel strategy for reversing the immunosuppressive TME and improving immunotherapeutic efficacy through live macrophage-mediated gene delivery.

Advances in research and current challenges in the treatment of advanced HER2-low breast cancer

Human epidermal growth factor receptor 2 (HER2)-low breast cancer is defined as breast cancer with an immunohistochemistry (IHC) score of 1+ or 2+ and in situ hybridisation (ISH)-negative. The traditional HER2 classification (negative or positive) has limitations, with only 15%-20% of the breast cancer population being positive and suitable for HER2-targeted therapy. The new clinical study, DESTINY-Breast04, shows that trastuzumab deruxtecan (T-DXd) has a significant effect on advanced HER2-low breast cancers, a classification that accounts for approximately half of the advanced breast cancer population. However, the detection methods and evaluation criteria for HER2-low breast cancer have not yet been standardised, and the toxicity and resistance mechanisms associated with T-DXd therapy are still unclear. This article focuses on these issues and describes the progress and challenges of T-DXd-related therapy in the treatment of advanced breast cancer patients with low HER2 expression.

Programmed cell death-related prognostic genes mediate dysregulation of the immune microenvironment in triple-negative breast cancer

Background

Programmed Cell death (PCD) encompasses a spectrum of genetically regulated cell death processes and plays a double-edged sword role in neoplastic progression and therapeutic resistance of Triple-Negative Breast Cancer(TNBC)through the tumor microenvironment (TME). However, the specific mechanisms by which PCD mediates microenvironmental dysregulation remain elusive.

Methods

Analyzing nine samples of TNBC through single-cell RNA sequencing (scRNA-seq), this study employed nonnegative matrix factorization (NMF) to assess genes associated with 13 PCD modes. Single-cell regulatory network inference and clustering (SCENIC), Monocle, CellChat, and scMetabolism were used for pseudotime analysis, intercellular communication mapping, determination of transcription factor activities (TFs), and immune infiltration of PCD-related cell clusters in TME. A robust prognostic model and drug resistance analysis were constructed using gene set enrichment analysis (GSEA), Kaplan-Meier survival analysis, and multivariable Cox regression. Finally, hub genes and critical PCD-related cell clusters were validated in the clinical breast cancer samples and the TNBC model mice.

Results

This investigation demonstrated that PCD significantly modulated the functional and phenotypic diversity of fibroblasts, macrophages, T cells, and B cells in the TME of TNBC. Furthermore, this study revealed that PCD-regulated CEBPB-positive cancer-associated fibroblast (CAF) populations are a key determinant of the TNBC immune Microenvironment heterogeneity and poor prognosis. Notably, CellChat analysis unveiled diverse and extensive interactions between PCD-related cell clusters and tumor immune cells, highlighting the CEBPB+ CAF subtype as a signaling ligand communicated with other immune cell clusters through the Midkine (MDK)-Nucleolin (NCL) signaling axis. Moreover, the TIDE analysis verified that CEBPB+ CAF is a predictor of poor prognosis in Immunotherapy. The ex vivo analyses of tumor specimens from both TNBC patients and syngeneic murine models were performed by quantitative reverse-transcription PCR (qRT-PCR), immunoblotting, immunohistochemical staining, and multiplexed immunofluorescence co-localization assays. They confirmed differential expression of the PCD-related prognostic genes and the presence of CEBPB+ CAFs.

Conclusion

In summary, our study provides a comprehensive molecular framework to understand the role of PCD-mediated TME dysregulation in TNBC pathogenesis. This study also offers new insights into the underlying mechanisms of immune therapy resistance in TNBC and identifies promising therapeutic targets for enhancing treatment efficacy and patient outcomes.

Lipid metabolic reprograming: the unsung hero in breast cancer progression and tumor microenvironment

Aberrant lipid metabolism is a well-recognized hallmark of cancer. Notably, breast cancer (BC) arises from a lipid-rich microenvironment and depends significantly on lipid metabolic reprogramming to fulfill its developmental requirements. In this review, we revisit the pivotal role of lipid metabolism in BC, underscoring its impact on the progression and tumor microenvironment. Firstly, we delineate the overall landscape of lipid metabolism in BC, highlighting its roles in tumor progression and patient prognosis. Given that lipids can also act as signaling molecules, we next describe the lipid signaling exchanges between BC cells and other cellular components in the tumor microenvironment. Additionally, we summarize the therapeutic potential of targeting lipid metabolism from the aspects of lipid metabolism processes, lipid-related transcription factors and immunotherapy in BC. Finally, we discuss the possibilities and problems associated with clinical applications of lipid‑targeted therapy in BC, and propose new research directions with advances in spatiotemporal multi-omics.

A Self-Amplifying Photodynamic Biomedicine for Cascade Immune Activation Against Triple-Negative Breast Cancer

The efficacy of immunotherapy in triple-negative breast cancer (TNBC) is significantly hindered by its low immunogenicity and immunosuppressive tumor microenvironment. Non-invasive photodynamic therapy (PDT) is increasingly recognized as a potential immunotherapeutic stimulant in the treatment of TNBC. However, photodynamic immunotherapy is constrained by tumor hypoxia and excessive inflammation suppression during the course of treatment. Herein, a simple and efficacious biomedicine is formulated to overcome adverse influences by amplifying photodynamic immunotherapy, thereby stimulating the systemic immune response. Specifically, the approach targeted tumor delivery by employing specific agents such as the photosensitizer (verteporfin), the hypoxic ameliorator (atovaquone), and the cyclooxygenase-2/prostaglandin E2 (COX-2/PGE2) signaling blocker (celecoxib). More importantly, the biomedicine effectively ameliorated hypoxia and inhibited COX-2/PGE2 signaling, thereby amplifying PDT-induced immunogenic cell death. This, in turn, enhanced the efficacy of photodynamic immunotherapy and triggered a robust immune response cascade. Notably, the self-amplifying photodynamic biomedicine significantly inhibited primary tumors, distal tumors, lung metastases, and post-operative recurrence while maintaining high biocompatibility. To sum up, the work provides a viable cascade stimulation approach and an efficient biomedical nanoplatform, offering a novel strategy for photodynamic immunotherapy of TNBC in the clinic.

Unveiling the role of MDH1 in breast cancer drug resistance through single-cell sequencing and schottenol intervention

This study utilizes single-cell RNA sequencing data to reveal the transcriptomic characteristics of breast cancer and normal epithelial cells. Nine significant cell populations were identified through stringent quality control and batch effect correction. Further classification of breast cancer epithelial cells based on the PAM50 method and clinical subtypes highlighted significant heterogeneity between triple-negative breast cancer (TNBC) and non-triple-negative breast cancer (NTNBC). The study also analyzed myeloid cells and tumor-infiltrating lymphocytes (TILs) within the breast cancer immune microenvironment, identifying 14 TIL subpopulations and assessing their proportion variations across different patients. The CellChat tool revealed a complex cellular communication network within the tumor microenvironment, showing notable differences in communication intensity and patterns between TNBC and NTNBC patients. Additionally, the key regulatory role of the senescence-associated gene MDH1 in breast cancer was confirmed, and its impact on drug sensitivity was explored. Finally, it was discovered that the phytosterol Schottenol inhibits breast cancer cell proliferation by downregulating MDH1 expression and enhances sensitivity to paclitaxel. These findings provide new insights into MDH1 as a therapeutic target and suggest Schottenol as a potential strategy to overcome breast cancer drug resistance.

Association of tumor-infiltrating lymphocytes with clinical outcomes in patients with triple-negative breast cancer receiving neoadjuvant chemotherapy: a systematic review and meta-analysis

OBJECTIVE

Triple-negative breast cancer (TNBC) presents a clinical challenge as an aggressive tumor, correlated with unfavorable prognosis. Tumor-infiltrating lymphocytes (TILs) have garnered interest as a potential prognostic biomarker. However, the disparity in outcomes between varying TILs rates remains inadequately explored.

METHODS

PubMed, Scopus, Web of Science, and Cochrane databases were searched for studies about the prognostic value of TILs in patients with TNBC receiving neoadjuvant chemotherapy. The hazard ratios (HRs) or odds ratios (ORs) were computed for binary endpoints, with 95% confidence intervals (CIs).

RESULTS

Twenty-nine studies were included, involving a population of six thousand one hundred sixty-one (80.41%) with TNBC. The cut-off TILs value ranged from 10 to 60%, with 50% being the most related value. Compared with the low-TIL expression group, the disease-free survival (DFS) (HR 0.71; 95% CI 0.61-0.82; p < 0.00001) and overall survival (OS) (HR 0.76; 95% CI 0.63-0.90; p = 0.002) rates showed significant improvement with higher TIL infiltrations. In the subgroup analyses of the lymphocyte subtypes CD4 + and CD8 + , there was statistical significance favoring higher TILs rates in both subtypes, each associated with improved DFS (HR 0.48; 95% CI 0.33-0.71; p = 0.0002) and OS (HR 0.53; 95% CI 0.36-0.78; p = 0.001), regardless of which cell subtype was predominantly infiltrated. The complete pathological response analysis showed better rates for the higher TIL group than the control for both the TIL (OR 1.29; 95% CI 1.13-1.48; p = 0.0003) and Ki-67 (OR 2.74; 95% CI 2.01-3.73; p < 0.00001) analyses.

CONCLUSION

Higher expressions of TILs in patients with TNBC were associated with improved significantly DFS, OS, and pCR outcomes.

Discovery of a Novel Selective and Cell-Active N6-Methyladenosine RNA Demethylase ALKBH5 Inhibitor

N6-methyladenosine (m6A), the most abundant methylation on mRNA, plays pivotal roles in regulating mRNA biological functions, which affect cell functions. ALKBH5, an m6A demethylase, was found to be an oncogene in several cancer types, including triple-negative breast cancer (TNBC). Here, we report a novel and selective ALKBH5 covalent inhibitor, W23-1006, through virtual screening and structure optimization. It covalently bonds to the ALKBH5 C200 residue with an IC50 value of 3.848 μM, representing roughly 30- and 8-fold stronger inhibitory activity than that against FTO and ALKBH3, respectively. Cellular experiments demonstrated that W23-1006 could efficiently enhance the m6A level on fibronectin 1 (FN1) mRNA, leading to strong suppression of TNBC cell proliferation and migration in vitro as well as tumor growth and metastasis in vivo. Collectively, our study developed a novel, selective, and cell-active ALKBH5 covalent inhibitor, W23-1006, which could be a potential therapeutic option for cancer, such as TNBC treatment.

Tumor cell-derived EMP1 is essential for cancer-associated fibroblast infiltration in tumor microenvironment of triple-negative breast cancer

The role of epithelial membrane protein 1 (EMP1) in tumor microenvironment (TME) remodeling has not yet been elucidated. In addition, the biological function of EMP1 in triple-negative breast cancer (TNBC) is largely unclear. In this study, we examined the infiltration landscape of cell types in the TME of breast cancer, and found that EMP1 expression was positively correlated with stromal and microenvironmental scores. Infiltration analysis and immunohistochemical (IHC) staining of serial sections confirmed the critical role of EMP1 in cancer-associated fibroblast (CAF) infiltration. Cell co-culture assays, xenograft tumor experiments, loss-of-function, gain-of-function, RNA sequencing studies, and rescue assays were performed to confirm the role of EMP1 in CAF infiltration in vitro and in vivo. These findings revealed that EMP1 depletion in TNBC cells resulted in considerable inhibition of CAF infiltration in vivo and in vitro. Mechanistically, EMP1 knockdown induced a substantial decrease in IL6 secretion from TNBC through the NF-κB signaling pathway, hindering CAF proliferation and subsequently inhibiting TNBC progression and metastasis. These cumulative results indicate that EMP1 functions as an oncogene in TNBC by mediating the cell communication of TNBC and CAFs. Targeted inhibition of EMP1 by suppressing CAF infiltration is a promising strategy for TNBC treatment.

The neuroscience in breast cancer: Current insights and clinical opportunities

The involvement of nerves in the development of breast cancer has emerged as a significant factor. Interaction between the nervous system and breast cancer can influence tumor initiation, growth, invasion, metastasis, reverse resistance to drugs, promote inflammation in tumors, and impair the immune system's ability to combat cancer. This review examined the intricate relationship linking the nervous system with breast cancer, emphasizing both central and peripheral aspects of the nervous system. Moreover, we reviewed neural cell factors and their impact on breast cancer progression, alongside the interactions between nerves and immunology, microbiota in breast cancer. Furthermore, the study discussed the potential of nerves as biomarkers for diagnosing and prognosticating breast cancer, and evaluated prospects for improving chemotherapy and immunotherapy therapeutic outcomes in breast cancer treatment. We hope to provide a deeper understanding of the neurobiological underpinnings of breast cancer and pave the way for the discovery of innovative therapeutic targets and prognostic markers.

Combination of adenosine blockade and ferroptosis for photo-immunotherapy of triple negative breast cancer with aptamer-modified copper sulfide

Combination of immunotherapy and photothermal therapy (PTT) provides a promising therapeutic performance for tumors. However, it still faces negative feedback from suppressive factors such as adenosine. Herein, we developed a new nanodrug that can combine adenosine blockade and ferroptosis to promote the photoimmunotherapy of triple negative breast cancer (TNBC). The nanodrug, named CuS-PEG@Apt, was constructed via the modification of copper sulfide (CuS) nanoparticles with adenosine aptamer and PEG. CuS-PEG@Apt could be effectively enriched in the tumor site and locally generate a strong photothermal effect, directly ablating tumors and inducing immunogenic death (ICD). On the other hand, the aptamers could block the adenosine pathway to inhibit the immune suppression by adenosine, which further promoted the anti-tumor immunity. Moreover, the CuS nanoparticles could consume GSH and inhibit GPX4 to cause the ferroptosis of tumor cells. Collectively, CuS-PEG@Apt achieved potent efficacy of tumor suppression via the combination of PTT, immune activation and ferroptosis, representing an appealing platform for TNBC treatment.

Platycodon grandiflorum-derived extracellular vesicles suppress triple-negative breast cancer growth by reversing the immunosuppressive tumor microenvironment and modulating the gut microbiota

Despite the approval of several artificial nanotherapeutics for the treatment of triple-negative breast cancer (TNBC), significant challenges, including unsatisfactory therapeutic outcomes, severe side effects, and the high cost of large-scale production, still restrict their long-term application. In contrast, plant-derived extracellular vesicles (PEVs) exhibit promising potential in cancer therapy due to their negligible systemic toxicity, high bioavailability and cost- effectiveness. In this study, we developed an alternative strategy to inhibit TNBC via Platycodon grandiflorum (PG)-derived extracellular vesicles (PGEVs). The PGEVs were isolated by ultracentrifugation and sucrose gradient centrifugation method and contained adequate functional components such as proteins, lipids, RNAs and active molecules. PGEVs exhibited remarkable stability, tolerating acidic digestion and undergoing minimal changes in simulated gastrointestinal fluid. They were efficiently taken up by tumor cells and induced increased production of reactive oxygen species (ROS), leading to tumor cell proliferation inhibition and apoptosis, particularly in the TNBC cell line 4T1. Additionally, PGEVs facilitated the polarization of tumor-associated macrophages (TAMs) toward M1 phenotype and increased the secretion of pro-inflammatory cytokines. Further in vivo investigations revealed that PGEVs efficiently accumulated in 4T1 tumors and exerted significant therapeutic effects through boosting systemic anti-tumor immune responses and modulating the gut microbiota whether administered orally or intravenously (i.v.). In conclusion, these findings highlight PGEVs as a promising natural, biocompatible and efficient nanotherapeutic candidate for treating TNBC.

Advancements in clinical research and emerging therapies for triple-negative breast cancer treatment

Triple-negative breast cancer (TNBC), defined by the lack of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor 2 (HER2) expression, is acknowledged as the most aggressive form of breast cancer (BC), comprising 15%-20% of all primary cases. Despite the prevalence of TNBC, effective and well-tolerated targeted therapies remain limited, with chemotherapy continuing to be the mainstay of treatment. However, the horizon is brightened by recent advancements in immunotherapy and antibody-drug conjugates (ADCs), which have garnered the U.S. Food and Drug Administration (FDA) approval for various stages of TNBC. Poly (ADP-ribose) polymerase inhibitors (PARPi), particularly for TNBC with BRCA mutations, present a promising avenue, albeit with the challenge of resistance that must be addressed. The success of phosphoinositide-3 kinase (PI3K) pathway inhibitors in hormone receptor (HR)-positive BC suggests potential applicability in TNBC, spurring optimism within the research community. This review endeavors to offer a comprehensive synthesis of both established and cutting-edge targeted therapies for TNBC. We delve into the specifics of PARPi, androgen receptor (AR) inhibitors, Cancer stem cells (CSCs), PI3K/Protein Kinase B (AKT)/mammalian target of rapamycin (mTOR), the transforming growth factor-beta (TGF-β), Ntoch, Wnt/β-catenin, hedgehog (Hh) pathway inhibitors, Epigenetic target-mediated drug delivery, ADCs, immune checkpoint inhibitors (ICIs)and novel immunotherapeutic solutions, contextualizing TNBC within current treatment paradigms. By elucidating the mechanisms of these drugs and their prospective clinical applications, we aim to shed light on the challenges and underscore the beacon of hope that translational research and innovative therapies represent for the oncology field.

Targeted Modulation of the Meningeal Lymphatic Reverse Pathway for Immunotherapy of Breast Cancer Brain Metastases

Treatment of tumor brain metastases remains challenging due to the ineffectiveness of drugs in crossing the blood-brain barrier (BBB). Here, we proposed a potential strategy to target and modulate the meningeal lymphatic system for immunotherapy of breast cancer brain metastases (BCBM) through peripheral administration. CT/fluorescence dual-modality imaging demonstrated that the phospholipid nanoprobe (α-PLNPs) through intracisternal magna injection effectively labeled and long-range tracked the meningeal lymphatic pathway from meningeal lymphatic vessels (MLVs) to periphery drainage cervical lymph nodes (CLNs). Interestingly, the reverse pathway from CLNs to MLVs was also successfully labeled with α-PLNPs through cervical subcutaneous injection, facilitating the noninvasive delivery of immunomodulators to the meningeal lymphatics. Given this, we used melittin-carrying α-M-PLNPs to trigger the modulation of the meningeal lymphatic reverse pathway, which effectively prevents BCBM and prolongs the survival of mice through activating the antigen-presenting cells in the CLNs and promoting the migration of CD8+ T cells into the metastatic brain tumors. This study highlights the potential of the meningeal lymphatic reverse pathway for the immunotherapy of BCBM, which holds great promise for central nervous system disease therapy without the need for drug delivery via BBB.

Selenium Nanoparticles Synergize with a KRAS Nanovaccine against Breast Cancer

Selenium (Se) is an element crucial for human health, known for its anticancer properties. Although selenium nanoparticles (SeNPs) have shown lower toxicity and higher biocompatibility than other Se compounds, bare SeNPs are unstable in aqueous solutions. In this study, several materials, including bovine serum albumin (BSA), chitosan, polymethyl vinyl ether-alt-maleic anhydride, and tocopherol polyethylene glycol succinate, are explored to develop stable SeNPs and further evaluate their potential as candidates for cancer treatment. All optimized SeNP are spherical, <100 nm, and with a narrow size distribution. BSA-stabilized SeNPs produced under acidic conditions present the highest stability in medium, plasma, and at physiological pH, maintaining their size ≈50-60 nm for an extended period. SeNPs demonstrate enhanced toxicity in cancer cell lines while sparing primary human dermal fibroblasts, underscoring their potential as effective anticancer agents. Moreover, the combination of BSA-SeNPs with a nanovaccine results in a strong tumor growth reduction in an EO771 breast cancer mouse model, demonstrating a three-fold decrease in tumor size. This synergistic anticancer effect not only highlights the role of SeNPs as effective anticancer agents but also offers valuable insights for developing innovative combinatorial approaches using SeNPs to improve the outcomes of cancer immunotherapy.

Gut microbiota interact with breast cancer therapeutics to modulate efficacy

The gut microbiome, or the community of microorganisms residing in the gastrointestinal tract, has emerged as an important factor in breast cancer etiology and treatment. Specifically, the impact of gut bacterial populations on breast cancer therapeutic outcomes is an emerging area of research. The microbiota's role in modifying the pharmacokinetics of chemotherapy and endocrine-targeting therapies can alter drug efficacy and toxicity profiles. In addition, the gut microbiome's capacity to regulate systemic inflammation and immune responses may influence the effectiveness of both conventional and immunotherapeutic strategies for the treatment of breast cancer. Overall, while the bidirectional interactions between the gut microbiome and breast cancer therapies are still being studied, its impact is increasingly recognized. Future research may provide more definitive insights and help develop personalized therapeutic strategies to harness the microbiome to improve breast cancer treatment outcomes.

Combined use of immunoreactivities of Efp and ZCCHC3 for predicting prognosis of patients with triple-negative breast cancer

We previously reported that strong immunoreactivity (IR) of estrogen-responsive finger protein (Efp), also known as tripartite motif-containing 25 (TRIM25), predicts poor prognosis in patients with estrogen receptor-positive and -negative invasive breast cancers. In the present study, we investigated the clinicopathological role of Efp and ZCCHC3, the latter of which is an Efp interactor, in a triple-negative breast cancer (TNBC) cohort which was composed of 118 Japanese female breast cancer patients underwent surgical treatment. Efp and ZCCHC3 IRs were analyzed using specific antibodies for these proteins. We demonstrated that positive Efp IR was significantly associated with shorter distant disease-free survival (p = 0.0108) and that positive ZCCHC3 IR was also significantly associated with shorter distant disease-free survival (p = 0.0153). Notably, ZCCHC3 IR was positively associated with Efp IR (p = 0.003). When IRs of the two proteins were combined, double positivity was associated with shorter distant disease-free survival (p = 0.0007) and was an independent factor for poor prognosis. These results suggest that IR positivity of Efp and ZCCHC3 has clinical significance as a poor prognostic factor in patients with TNBC. Thus, we propose that the combined use of both IRs can be used as a prognostic marker for TNBC.

(E)-1-(3-(3-Hydroxy-4-Methoxyphenyl)-1-(3,4,5-Trimethoxyphenyl)allyl)-1H-1,2,4-Triazole and Related Compounds: Their Synthesis and Biological Evaluation as Novel Antimitotic Agents Targeting Breast Cancer

Background/Objectives: The synthesis of (E)-1-(1,3-diphenylallyl)-1H-1,2,4-triazoles and related compounds as anti-mitotic agents with activity in breast cancer was investigated. These compounds were designed as hybrids of the microtubule-targeting chalcones, indanones, and the aromatase inhibitor letrozole. Methods: A panel of 29 compounds was synthesized and examined by a preliminary screening in estrogen receptor (ER) and progesterone receptor (PR)-positive MCF-7 breast cancer cells together with cell cycle analysis and tubulin polymerization inhibition. Results: (E)-5-(3-(1H-1,2,4-triazol-1-yl)-3-(3,4,5-trimethoxyphenyl)prop-1-en-1-yl)-2-methoxyphenol 22b was identified as a potent antiproliferative compound with an IC50 value of 0.39 mM in MCF-7 breast cancer cells, 0.77 mM in triple-negative MDA-MB-231 breast cancer cells, and 0.37 mM in leukemia HL-60 cells. In addition, compound 22b demonstrated potent activity in the sub-micromolar range against the NCI 60 cancer cell line panel including prostate, melanoma, colon, leukemia, and non-small cell lung cancers. G2/M phase cell cycle arrest and the induction of apoptosis in MCF-7 cells together with inhibition of tubulin polymerization were demonstrated. Immunofluorescence studies confirmed that compound 22b targeted tubulin in MCF-7 cells, while computational docking studies predicted binding conformations for 22b in the colchicine binding site of tubulin. Compound 22b also selectively inhibited aromatase. Conclusions: Based on the results obtained, these novel compounds are suitable candidates for further investigation as antiproliferative microtubule-targeting agents for breast cancer.

Integrated Network Pharmacology, Machine Learning and Experimental Validation to Identify the Key Targets and Compounds of TiaoShenGongJian for the Treatment of Breast Cancer

Background

TiaoShenGongJian (TSGJ) decoction, a traditional Chinese medicine for breast cancer, has unknown active compounds, targets, and mechanisms. This study identifies TSGJ's key targets and compounds for breast cancer treatment through network pharmacology, machine learning, and experimental validation.

Methods

Bioactive components and targets of TSGJ were identified from the TCMSP database, and breast cancer-related targets from GeneCards, PharmGkb, and RNA-seq datasets. Intersection of these targets revealed therapeutic targets of TSGJ. PPI analysis was performed via STRING, and machine learning methods (SVM, RF, GLM, XGBoost) identified key targets, validated by GSE70905, GSE70947, GSE22820, and TCGA-BRCA datasets. Pathway analyses and molecular docking were performed. TSGJ and core compounds' effectiveness was confirmed by MTT and RT-qPCR assays.

Results

160 common targets of TSGJ were identified, with 30 hub targets from PPI analysis. Five predictive targets (HIF1A, CASP8, FOS, EGFR, PPARG) were screened via SVM. Their diagnostic, biomarker, immune, and clinical values were validated. Quercetin, luteolin, and baicalein were identified as core components. Molecular docking confirmed their strong affinities with predicted targets. These compounds modulated key targets and induced cytotoxicity in breast cancer cell lines in a similar way as TSGJ.

Conclusion

This study reveals the main active components and targets of TSGJ against breast cancer, supporting its potential for breast cancer prevention and treatment.

Glycosylation profiling of triple-negative breast cancer: clinical and immune correlations and identification of LMAN1L as a biomarker and therapeutic target

Introduction

Breast cancer (BC) is the most prevalent malignant tumor in women, with triple-negative breast cancer (TNBC) showing the poorest prognosis among all subtypes. Glycosylation is increasingly recognized as a critical biomarker in the tumor microenvironment, particularly in BC. However, the glycosylation-related genes associated with TNBC have not yet been defined. Additionally, their characteristics and relationship with prognosis have not been deeply investigated.

Methods

Transcriptomic analyses were used to identify a glycosylation-related signature (GRS) associated with TNBC prognosis. A machine learning-based prediction model was constructed and validated across multiple independent datasets. The model's predictive capability was extended to evaluate the prognosis of TNBC individuals, tumor immune microenvironment and immunotherapy response. LMAN1L (Lectin, Mannose Binding 1 Like) was identified as a novel prognostic marker in TNBC, and its biological effects were validated through experimental assays.

Results

The GRS showed significant prognostic relevance for TNBC patients. The risk model effectively predicted molecular features, including immune cell infiltration and potential responses to immunotherapy. Experimental validation confirmed LMAN1L as a novel glycosylation-related prognostic gene, with low expression significantly inhibiting TNBC cell proliferation and migration.

Discussion

Our GRS risk model demonstrates robust predictive capability for TNBC prognosis and immunotherapy response. This model offers a promising strategy for personalized treatment and improved clinical outcomes in TNBC.

Mechanistic exploration of Traditional Chinese Medicine regulation on tumor immune microenvironment in the treatment of triple-negative breast cancer: based on CiteSpace and bioinformatics analysis

Background

Triple-negative breast cancer (TNBC) is a highly aggressive subtype of breast cancer, characterized by frequent recurrence, metastasis, and poor survival outcomes despite chemotherapy-based treatments. This study aims to investigate the mechanisms by which Traditional Chinese Medicine (TCM) modulates the tumor immune microenvironment in TNBC, utilizing CiteSpace and bioinformatics analysis.

Methods

We employed CiteSpace to analyze treatment hotspots and key TCM formulations, followed by bioinformatics analysis to identify the main active components, targets, associated pathways, and their clinical implications in TNBC treatment.

Results

CiteSpace analysis highlighted key TCM formulations, including Sanhuang Decoction. Network pharmacology identified major bioactive components such as Mutatochrome, Physcion diglucoside, Procyanidin B-5,3'-O-gallate, gallic acid-3-O-(6'-O-galloyl)-glucoside, and isomucronulatol-7,2'-di-O-glucosiole, with core targets including Mitogen-Activated Protein Kinase 1 (MAPK1), Janus Kinase 2 (JAK2), and Lymphocyte-specific protein tyrosine kinase (LCK). These targets were found to be involved in immune regulation, particularly the modulation of CD8+ and CD4+ T cells. Additionally, core targets were associated with improved recurrence-free survival (RFS) and overall survival (OS) in TNBC patients.

Conclusion

The therapeutic effects of TCM in TNBC primarily involve immune modulation within the tumor microenvironment, particularly through the regulation of CD8+ and CD4+ T cells.

MORF4L2 induces immunosuppressive microenvironment and immunotherapy resistance through GRHL2/MORF4L2/H4K12Ac/CSF1 axis in triple-negative breast cancer

BACKGROUND

Although immunotherapy has achieved great progress in advanced triple-negative breast cancer (TNBC), there are still numerous patients who do not benefit from immunotherapy. Therefore, identification of the key molecule that induces immune escape and clarification of its specific mechanism in TNBC are urgently needed.

METHODS

In this research, single cell sequencing and bulk sequencing were conducted for biomarker screening. Immunohistochemistry, multiplex immunofluorescence, and orthotopic TNBC tumor model were applied in identifying the key molecule driving immune escape. At the mechanical level, RNA sequencing, in vitro co-culturing system, flow cytometry, Western blotting, ELISA, and real-time qPCR were carried out.

RESULTS

Mortality factor 4 like 2 (MORF4L2) expression is significantly up-regulated among patients who developed anti-PD1 resistance. MORF4L2 enhances anti-PD1 resistance by inducing the chemotaxis of macrophage infiltration and promoting their polarization towards the alternative activation phenotype (M2), thus creating an immunosuppressive microenvironment. Mechanistically, MORF4L2 actes as part of NuA4 histone acetyltransferase (HAT) complex, contributes to to histone 4 lysine 12 acetylation (H4K12Ac) and activates the downstream transcription of macrophage colony-stimulating factor (CSF1). CSF1 is secreted by tumor cells and binds to the macrophage-surface CSF1 receptor (CSF1R), which chemotactically converted and polarized macrophages to the M2 phenotype. Furthermore, we revealed that grainyhead like transcription factor 2 (GRHL2) could promote MORF4L2 transcription by binding to the MORF4L2 enhancer region. Notably, BLZ549, an inhibitor of CSF1R, restored the anti-PD1 sensitivity by blocking the GRHL2/MORF4L2/H4K12Ac/CSF1 axis.

CONCLUSIONS

GRHL2/MORF4L2/H4K12Ac/CSF1 axis plays an important role in anti-PD1 resistance. CSF1R inhibitors can reverse GRHL2/MORF4L2-mediated anti-PD1 resistance.

Discovery of a novel Fam20C inhibitor for treatment of triple-negative breast cancer

Sequence similarity 20 family member C (Fam20C), a Golgi casein kinase, has a gradually elucidated mechanism in triple-negative breast cancer (TNBC) and is considered a possible target for therapeutic intervention. In this study, we combined virtual screening and chemical synthesis methods to obtain a new small-molecule Fam20C inhibitor, compound 5k, which possesses desirable kinase inhibitory activity against Fam20C and significant anti-proliferative activity against MDA-MB-231 and BT-549 cells. Subsequently, cellular thermal shift assay (CETSA), molecular docking, and molecular dynamics (MD) simulations revealed that compound 5k binds to Fam20C. Moreover, compound 5k showed favorable antitumor efficacy in TNBC cells and xenograft models by promoting apoptosis and inhibiting migration. Mechanistically, compound 5k can inhibit the proliferation, promote apoptosis, and inhibit migration of TNBC cells by targeting Fam20C, thereby inhibiting the deterioration of TNBC and preventing its progression. Taken together, these results suggest that compound 5k can be utilized as a novel Fam20C inhibitor, laying a foundation for the discovery of more small-molecule drugs for the treatment of TNBC in the future.

Hybrid Cell Membrane-Coated Nanoparticles for Synergizing Sonodynamic Therapy and Immunotherapy against Triple-Negative Breast Cancer

Tumor immunotherapy represents a highly promising modality for the treatment of triple-negative breast cancer (TNBC). Nevertheless, its therapeutic efficacy has been profoundly impacted by challenges such as low drug uptake, hypoxia, and immunosuppression. To address these problems, the study develops a strategy combining sonodynamic therapy (SDT) and immunotherapy using biomimetic nanoparticles coated with hybrid membranes. The nanoparticles are loaded with semiconducting polymers (PFODBT), Atovaquone (ATO), and TMP195 to enhance biocompatibility, targeting ability, and drug uptake and retention at the tumor site. In in vitro experiments, the biomimetic nanoparticles alleviate hypoxia, induce immunogenic cell death (ICD), and prompt reprogramming of tumor-associated macrophages (TAMs) from M2 type to M1 type. In in vivo experiments, the synergistic effects of enhanced SDT-mediated ICD and TAMs repolarization significantly inhibit the proliferation of primary and distant tumor in the 4T1 subcutaneous tumor model, and effectively attenuated metastasis of lung and liver. Moreover, the in vivo immune responses are further activated by improving the maturation of dendritic cells, filtration of CD8+ T cells, and depletion of regulatory T cells. This study offers a novel strategy for TNBC therapy by converting the tumor microenvironment from the "cold" into "hot" tumor through multiple synergistic therapies.

Analyses of the MYBL1 Gene in Triple Negative Breast Cancer: Evidence of Regulation of the VCPIP1 Gene and Identification of a Specific Exon Overexpressed in Tumor Cell Lines

Previous data show that the knockdown of the MYBL1 gene in the MDA-MB-231 cell line leads to the downregulation of VCPIP1 gene expression. In addition, MYBL1 and VCPIP1 genes are co-expressed and dysregulated in some of the same triple negative breast cancer patient samples. We propose that the co-expression of the two genes is attributed to the MYBL1 transcription factor regulation of the VCPIP1 gene. We identify the MYBL1 transcription factor binding site upstream of the VCPIP1 start site and show that the MYBL1 protein can bind to the sequence identified in the VCPIP1 promoter region. Combined with the results from the knockdown study, these data support the ability of MYBL1 to regulate the VCPIP1 gene. The VCPIP1 gene functions as a deubiquitinating enzyme involved in DNA repair, protein positioning, and the assembly of the Golgi apparatus during mitotic signaling. The transcriptional regulation of VCPIP1 by the MYBL1 gene could implicate MYBL1 in these processes, which might contribute to tumor processes in TNBC. Although both genes are involved in cell cycle regulatory mechanisms, converging signaling mechanisms have not been identified. In a separate study, we performed sequence alignment of the MYBL1 transcript variants and identified an exon unique to the canonical variant. Probes that specifically target the unique MYBL1 exon show that the exon is overexpressed in tumor cell lines compared to non-tumor breast cells. We are classifying this unique MYBL1 exon as a tumor-associated exon.

Tumor microenvironment and immunotherapy for triple-negative breast cancer

Triple-negative breast cancer (TNBC) is a subtype of breast cancer known for its high aggressiveness and poor prognosis. Conventional treatment of TNBC is challenging due to its heterogeneity and lack of clear targets. Recent advancements in immunotherapy have shown promise in treating TNBC, with immune checkpoint therapy playing a significant role in comprehensive treatment plans. The tumor microenvironment (TME), comprising immune cells, stromal cells, and various cytokines, plays a crucial role in TNBC progression and response to immunotherapy. The high presence of tumor-infiltrating lymphocytes and immune checkpoint proteins in TNBC indicates the potential of immunotherapeutic strategies. However, the complexity of the TME, while offering therapeutic targets, requires further exploration of its multiple roles in immunotherapy. In this review, we discuss the interaction mechanism between TME and TNBC immunotherapy based on the characteristics and composition of TME, and elaborate on and analyze the effect of TME on immunotherapy, the potential of TME as an immune target, and the ability of TME as a biomarker. Understanding these dynamics will offer new insights for enhancing therapeutic approaches and investigating stratification and prognostic markers for TNBC patients.

Therapeutic strategies for fungating and ulcerating breast cancers: A systematic review and narrative synthesis

BACKGROUND

To identify optimal therapeutic strategies for managing fungating, large or ulcerating breast tumors and highlight existing gaps in the literature.

METHODS

We conducted a systematic search of Medline, Embase, APA, PsycInfo, CAB abstracts, Scopus, and Web of Science from inception to June 30, 2024, including studies on patients with fungating, large, or ulcerating breast cancers.

RESULTS

The search identified 7917 studies, with 79 meeting the inclusion criteria: 62 case reports, 7 case series, and 10 cohort studies. Owing to high heterogeneity, a narrative synthesis was performed, categorizing treatment by year, molecular subtype, histology, and staging. We found that treatment modalities increased, from an average of two in luminal-B cancers to three in HER2-positive cases, with over half achieving complete response. Triple-negative breast cancers averaged two modalities, with around half showing only partial response. Cohort analysis revealed a significant positive correlation between metastasis rate and radiotherapy use (Spearman's rho = 0.828, p = 0.042) and between chemotherapy and hormonal therapy use (rho = 0.69, p = 0.04). Median survival was positively correlated with surgical treatment (rho = 0.82, p = 0.046).

CONCLUSIONS

Local treatment is crucial for symptomatic palliation in fungating or ulcerating breast tumors, and histology should guide therapeutic choices. While local treatments remain primary, emerging systemic therapies show promise and may soon become first-line options. As the first systematic review on this topic, our study faced considerable source heterogeneity, precluding a meta-analysis. Instead, we analyzed treatment trends by demographics and tumor characteristics, providing a comprehensive overview and encouraging further research in this area.

Clinicopathological characteristics and long-term prognosis of triple-negative breast cancer patients with HER2-Low expression: a retrospective propensity score-matched cohort study

PURPOSE

The objective of the current research was to assess the clinicopathological characteristics and long-term prognosis of triple-negative breast cancer (TNBC) patients with human epidermal growth factor receptor 2 (HER2)-low status following breast surgery.

METHODS

A total of 202 TNBC patients treated at Qingdao Central Hospital from January 2010 to December 2019 were included, comprising 71 HER2-low and 131 HER2-zero patients. Propensity score matching (PSM) was applied to minimize differences between the cohorts.

RESULTS

HER2-low TNBC patients had lower histological grade, lower Ki-67 expression levels, and a higher prevalence of hypertension compared to HER2-zero TNBC patients. Before and after PSM, the HER2-low group consistently exhibited a lower recurrence rate and longer RFS compared to HER2-zero TNBC patients. HER2-low status was validated as an independent low-risk factor for RFS both pre-PSM (HR 0.354, 95% CI 0.178-0.706, p = 0.003) and post-PSM (HR 0.405, 95% CI 0.185-0.886, p = 0.024). No statistically significant differences in mortality rate and OS were observed, both before and after PSM.

CONCLUSIONS

HER2-low and HER2-zero TNBC patients show significant clinicopathological differences. Compared to HER2-zero, HER2-low status is linked to better long-term prognosis and serves as an independent low-risk factor for RFS in TNBC patients.

Remodeling of tumour microenvironment: strategies to overcome therapeutic resistance and innovate immunoengineering in triple-negative breast cancer

Triple-negative breast cancer (TNBC) stands as the most complex and daunting subtype of breast cancer affecting women globally. Regrettably, treatment options for TNBC remain limited due to its clinical complexity. However, immunotherapy has emerged as a promising avenue, showing success in developing effective therapies for advanced cases and improving patient outcomes. Improving TNBC treatments involves reducing side effects, minimizing systemic toxicity, and enhancing efficacy. Unlike traditional cancer immunotherapy, engineered nonmaterial's can precisely target TNBC, facilitating immune cell access, improving antigen presentation, and triggering lasting immune responses. Nanocarriers with enhanced sensitivity and specificity, specific cellular absorption, and low toxicity are gaining attention. Nanotechnology-driven immunoengineering strategies focus on targeted delivery systems using multifunctional molecules for precise tracking, diagnosis, and therapy in TNBC. This study delves into TNBC's tumour microenvironment (TME) remodeling, therapeutic resistance, and immunoengineering strategies using nanotechnology.

Targeting cuproptosis with nano material: new way to enhancing the efficacy of immunotherapy in colorectal cancer

Colorectal cancer has emerged as one of the predominant malignant tumors globally. Immunotherapy, as a novel therapeutic methodology, has opened up new possibilities for colorectal cancer patients. However, its actual clinical efficacy requires further enhancement. Copper, as an exceptionally crucial trace element, can influence various signaling pathways, gene expression, and biological metabolic processes in cells, thus playing a critical role in the pathogenesis of colorectal cancer. Recent studies have revealed that cuproptosis, a novel mode of cell death, holds promise to become a potential target to overcome resistance to colorectal cancer immunotherapy. This shows substantial potential in the combination treatment of colorectal cancer. Conveying copper into tumor cells via a nano-drug delivery system to induce cuproptosis of colorectal cancer cells could offer a potential strategy for eliminating drug-resistant colorectal cancer cells and vastly improving the efficacy of immunotherapy while ultimately destroy colorectal tumors. Moreover, combining the cuproptosis induction strategy with other anti-tumor approaches such as photothermal therapy, photodynamic therapy, and chemodynamic therapy could further enhance its therapeutic effect. This review aims to illuminate the practical significance of cuproptosis and cuproptosis-inducing nano-drugs in colorectal cancer immunotherapy, and scrutinize the current challenges and limitations of this methodology, thereby providing innovative thoughts and references for the advancement of cuproptosis-based colorectal cancer immunotherapy strategies.

Combining ultrasound technology with targeted fucoidan/arginine-gelatin nanoparticles loaded with doxorubicin to enhance therapeutic efficacy and modulate bioeffects in drug-resistant triple-negative breast cancer

Triple-negative breast cancer (TNBC) presents formidable challenges due to its aggressive nature and high recurrence rates, compounded by the involvement of epithelial-mesenchymal transition (EMT) in its progression and metastasis. Standard chemotherapy, which typically employs doxorubicin (DOX), remains a primary treatment approach. However, multidrug resistance (MDR) mechanisms, which include ATP-binding cassette transporters and EMT, contribute to treatment failures. Ultrasound has emerged as a promising modality among the various strategies explored to address MDR in TNBC. It serves as a diagnostic tool and holds therapeutic potential by inducing various biological effects depending on the exposure level. Targeted nanoparticles offer a means to enhance drug delivery efficiency. Our study aims to advance ultrasound technology combined with biocompatible nanoparticles using simplified preparation methods to improve treatment outcomes for drug-resistant TNBC. In particular, employing DOX-loaded fucoidan/arginine-gelatin nanoparticles facilitated the targeted delivery of chemotherapy drugs to tumors by effectively interacting with P-selectin, resulting in tumor growth inhibition. Furthermore, these nanoparticles mitigated MDR and EMT, particularly when combined with ultrasound treatment. This integrated approach of nanoparticle delivery with ultrasonography opens up a promising and innovative avenue for clinical cancer research.

Broadening horizons: the multifaceted role of ferroptosis in breast cancer

Breast cancer poses a serious threat to women's health globally. Current radiotherapy and chemotherapy regimens can induce drug-resistance effects in cancer tissues, such as anti-apoptosis, anti-pyroptosis, and anti-necroptosis, leading to poor clinical outcomes in the treatment of breast cancer. Ferroptosis is a novel programmed cell death modality characterized by iron overload, excessive generation of reactive oxygen species, and membrane lipid peroxidation. The occurrence of ferroptosis results from the imbalance between intracellular peroxidation mechanisms (executive system) and antioxidant mechanisms (defensive system), specifically involving iron metabolism pathways, amino acid metabolism pathways, and lipid metabolism pathways. In recent years, it has been found that ferroptosis is associated with the progression of various diseases, including tumors, hypertension, diabetes, and Alzheimer's disease. Studies have confirmed that triggering ferroptosis in breast cancer cells can significantly inhibit cancer cell proliferation and invasion, and improve cancer cell sensitivity to radiotherapy and chemotherapy, making induction of ferroptosis a potential strategy for the treatment of breast cancer. This paper reviews the development of the concept of ferroptosis, the mechanisms of ferroptosis (including signaling pathways such as GSH-GPX4, FSP1-CoQ1, DHODH-CoQ10, and GCH1-BH4) in breast cancer disease, the latest research progress, and summarizes the research on ferroptosis in breast cancer disease within the framework of metabolism, reactive oxygen biology, and iron biology. The key regulatory factors and mechanisms of ferroptosis in breast cancer disease, as well as important concepts and significant open questions in the field of ferroptosis and related natural compounds, are introduced. It is hoped that future research will make further breakthroughs in the regulatory mechanisms of ferroptosis and the use of ferroptosis in treating breast cancer cells. Meanwhile, natural compounds may also become a new direction for potential drug development targeting ferroptosis in breast cancer treatment. This provides a theoretical basis and opens up a new pathway for research and the development of drugs for the prevention and treatment of breast cancer.

Studying the Role of Novel Carbon Nano Tubes as a Therapeutic Agent to Treat Triple Negative Breast Cancer (TNBC) - an In Vitro and In Vivo Study

Triple Negative Breast Cancer (TNBC) is a malignant cancer with a very high mortality rate around the world. African American(AA) women are 28% more likely to die from triple-negative breast cancer (TNBC) than white women with the same diagnosis. AA patients are also more likely to be diagnosed at a later stage of the disease and have the lowest survival rates for any stage of diagnosis; There are very few existing anti TNBC drugs with therapeutic efficacy hence newer anti TNBC drug design and investigation is needed. Carbon Nano Tubes(CNT) in recent years have shown effective anti-cancer properties in various types of cancers as reported in peer reviewed journals. Henceforth, we did an investigation to study the anticancer properties of a novel CNT in both in vitro and in vivo models of TNBC. We tested the CNT drug in vitro cytotoxicity studies on TNBC model MDA-MB-231 VIM RFP cell lines and Spheroid forming assays on the same cancer cells; we also did an in vivo study on TNBC model mice to study the therapeutic efficacy of this CNT drug in reducing the tumor load. Our initial studies showed increased cell death and reduction in spheroid numbers in the CNT treated cancer cells in comparison to control and a significant reduction in the tumor volume in the TNBC model mice than in untreated animals. Thus our initial studies have shown significant therapeutic efficacy of the novel CNT as an anti TNBC agent. Additional mechanistic studies need to be done to find out the cell death mechanisms, core canonical pathways involved, pharmacokinetic studies before translational research for this novel nanoparticle as a therapeutic agent from bench to bedside.

Effect and mechanisms of shikonin on breast cancer cells in vitro and in vivo

BACKGROUND

Breast cancer seriously affects physical and mental health of women. Despite advances in the clinical use of different treatments, breast cancer remains a major cause of mortality. Therefore, it is imperative to identify promising treatment options. In the present study, we investigated the effects of shikonin on 4T1 breast cancer cells and its potential mechanisms of action.

METHODS

BALB/c-derived mouse breast cancer 4T1 is very close to human breast cancer in growth characteristics and systemic response, so 4T1 cells were selected for further experiments. Cell viability, apoptosis, intracellular reactive oxygen species (ROS), mitochondrial activity, and cellular calreticulin (CRT) exposure were assessed to evaluate the antitumor effects and mechanisms of shikonin in vitro. Orthotopic tumor growth inhibition and splenic immune cell regulation by shikonin were evaluated in 4T1 breast cancer orthotopic mice in vivo.

RESULTS

In vitro, shikonin could inhibit cell proliferation, cause apoptosis, disrupt mitochondrial activity, and induce ROS production and CRT exposure. In vivo, shikonin inhibited tumor growth, increased the proportion of CD8+ T cells, and reduced the proportion of regulatory cells (CD25+ Foxp3+ T cells) in the spleen.

CONCLUSIONS

Shikonin inhibits the growth of 4T1 breast cancer cells by disrupting mitochondrial activity, promoting oxidative stress, and regulating immune function.

Evolving immunotherapeutic solutions for triple-negative breast carcinoma

Triple-negative breast carcinoma (TNBC) remains a formidable clinical hurdle owing to its high aggressiveness and scant therapeutic options. Nonetheless, the evolving landscape of immunotherapeutic strategies opens up promising avenues for tackling this hurdle. This review discusses the advancing immunotherapy for TNBC, accentuating personalized interventions due to tumor microenvironment (TME) diversity. Immune checkpoint inhibitors (ICIs) hold pivotal significance, both as single-agent therapies and when administered alongside cytotoxic agents. Moreover, the concurrent inhibition of multiple immune checkpoints represents a potent approach to augment the efficacy of cancer immunotherapy. Synergistic effects have been observed when ICIs are combined with targeted treatments like PARP inhibitors, anti-angiogenics, and ADCs (antibody-drug conjugates). Emerging tactics include tumor vaccines, cellular immunotherapy, and oncolytic viruses, leveraging the immune system's ability for selective malignant cell destruction. This review offers an in-depth examination of the diverse landscape of immunotherapy development for TNBC, furnishing meticulous insights into various advancements within this field. In addition, immunotherapeutic interventions offer hope for TNBC, needing further research for optimization.

Precision medicine in breast cancer (Review)

Precision medicine in breast cancer is a revolutionary approach that customizes diagnosis and treatment based on individual and tumor characteristics, departing from the traditional one-size-fits-all approach. Breast cancer is diverse, with various subtypes driven by distinct genetic mutations. Understanding this diversity is crucial for tailored treatment strategies that target specific vulnerabilities in each tumor. Genetic testing, particularly for mutations in breast cancer gene (BRCA) DNA repair-associated genes, helps assess hereditary risks and influences treatment decisions. Molecular subtyping guides personalized treatments, such as hormonal therapies for receptor-positive tumors and human epidermal growth factor receptor 2 (HER2)-targeted treatments. Targeted therapies, including those for HER2-positive and hormone receptor-positive breast cancers, offer more effective and precise interventions. Immunotherapy, especially checkpoint inhibitors, shows promise, particularly in certain subtypes such as triple-negative breast cancer, with ongoing research aiming to broaden its effectiveness. Integration of big data and artificial intelligence enhances personalized treatment strategies, while liquid biopsies provide real-time insights into tumor dynamics, aiding in treatment monitoring and modification. Challenges persist, including accessibility and tumor complexity, but emerging technologies and precision prevention offer hope for improved outcomes. Ultimately, precision medicine aims to optimize treatment efficacy, minimize adverse effects and enhance the quality of life for patients with breast cancer.

Advances in the Understanding of the Pathogenesis of Triple-Negative Breast Cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is a heterogeneous disease characterized by high aggressiveness, high malignancy, and poor prognosis compared to other breast cancer subtypes.

OBJECTIVE

This review aims to explore recent advances in understanding TNBC and to provide new insights and potential references for clinical treatment.

METHODS

We examined current literature on TNBC to analyze molecular subtypes, genetic mutations, signaling pathways, mechanisms of drug resistance, and emerging therapies.

RESULTS

Findings highlight key aspects of TNBC's molecular subtypes, relevant mutations, and pathways, alongside emerging treatments that target drug resistance mechanisms.

CONCLUSION

These insights into TNBC pathogenesis may help guide future therapeutic strategies and improve clinical outcomes for patients with TNBC.

The landscape of combining immune checkpoint inhibitors with novel Therapies: Secret alliances against breast cancer

This review focuses on the immune checkpoint inhibitors (ICIs) in the context of breast cancer (BC) management. These innovative treatments, by targeting proteins expressed on both tumor and immune cells, aim to overcome tumor-induced immune suppression and reactivate the immune system. The potential of this approach is the subject of numerous clinical studies. Here, we explore the key studies and emerging therapies related to ICIs providing a detailed analysis of their specific and combined use in BC treatment.