Treatment Of Triple-negative Breast Cancer Research Articles

Abstract 7151: Targeting metabolic pathway in triple negative breast cancer with a small molecule inhibitor

Abstract Background: Triple Negative Breast Cancer (TNBC) is the most aggressive type of breast cancer, making up 15-20% of diagnosed cases, and has high rates of metastasis and recurrence. Most women with this disease experience a recurrence after curative-intent therapy for early breast cancer, while a smaller proportions are diagnosed with distant metastases initially. Cancer cells are characterized by their reprogramming of glucose metabolism. Cancer cells show increased proliferation along with higher energy and substrate demands. Through our efforts to find effective therapies for TNBC, we have identified CET019, a new small molecule that effectively suppresses the growth of breast cancer cells. Methods: Cell viability and clonogenic assays were performed on a range of TNBC cells, including MDA-MB-231, MDA-MB-468, SUM159, HCC1395, HCC1806, EMT6, and 4T1. Cell cycle distribution was assessed through flow cytometry. LC-MS/MS analysis was performed on TMT-labeled samples for global proteome profiling. The efficacy of CET019 (30 mg/kg) was tested using tumor and patient derived xenograft studies. Results: Our studies show that CET019 suppresses the clonogenic potential and growth of various triple-negative breast cancer cells. The CET019 treatment causes cell cycle arrest in TNBC cells at the G2/M phase. Proteomics analysis suggests that CET019 specifically affects metabolic and proteosomal pathways. In vivo studies with CET019 found an inhibition of tumor growth kinetics in the mouse xenograft study with different TNBC models, as compared to the control group. We also observed that CET019 inhibited metastatic lung nodules. The results were further substantiated in three Patient Derived Xenograft (PDX) models. Conclusion: In summary, our study has identified a novel small molecule candidate CET019 as a promising lead candidate for TNBC treatment, paving the way for further development.“The complete chemical structures of the compounds used will be disclosed at the time of presentation at the meeting.” Citation Format: Arpit Dheeraj, Fernando Jose Marques, Dhanir Tailor, Abel Bermudez, Benedikt Grau, Sharon Pitteri, Sanjay V. Malhotra. Targeting metabolic pathway in triple negative breast cancer with a small molecule inhibitor [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 7151.

Abstract 2789: NCAPG promotes triple-negative breast cancer stemness by a positive feedback loop with HIF-1α

Abstract Objective: Triple-negative breast cancer (TNBC) is life-threatening because of limited therapies and lack of effective therapeutic targets. NCAPG, an oncogenic marker, might be served as a new target for TNBC treatment. Here, we aimed to elucidate the role of NCAPG played in TNBC and the underlying mechanism. Design: GEO data was used to investigate the potential targets for TNBC. Patient samples and TCGA data were used to demonstrate the clinical significance. Cell migration, self-renewal ability, chemoresistance and expression of pluripotency factors were tested to detect the stemness of TNBC cells. Immunoprecipitation, ubiquitination assay and chromatin immunoprecipitation assay were utilized to investigate the mutual regulation mechanism of NCAPG and HIF-1α. Results: NCAPG was significantly overexpressed in TNBC compared with other subtypes of breast cancer and was positively correlated with poor overall survival. Elevated NCAPG expression could enhance cancer stem-like cell properties of TNBC cells. Mechanically, NCAPG positively regulated HIF-1α protein stability by interacting with HIF-1α and competitively abrogating the E3 ligase FBXW7-mediated ubiquitination and degradation towards HIF-1α. NCAPG, as a direct target gene of HIF-1α, could be in turn transcriptionally upregulated by HIF-1α. Conclusion: NCAPG promotes TNBC stemness by a HIF-1α/NCAPG positive feedback loop. NCAPG is a promising target for TNBC treatment. Citation Format: Huimin Zhang, Peiling Xie, Rui An. NCAPG promotes triple-negative breast cancer stemness by a positive feedback loop with HIF-1α [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 2789.

Abstract 3716: Enhancing anti-tumor responses in triple-negative breast cancer by combining SIRPα inhibition with immunogenic chemotherapy or antibody-drug conjugates

Abstract Background: Triple-negative breast cancer (TNBC) is a subtype of breast cancer defined by the absence of hormone receptors and HER2 receptor on tumor cells. Because of a lack of targetable receptors and poor response to PD1/PDL1 immunotherapy, TNBC has limited systemic treatment options. In previous work using a genomic screen (Shuptrine et al., 2017), we identified CD47 as one of the leading factors that contributes to TNBC immune evasion. The CD47-SIRPα axis is an innate immune checkpoint that primarily regulates myeloid cells. In the context of cancer, tumor cells upregulate CD47 to engage SIRPα inhibitory signaling to block phagocytosis. While CD47 or SIRPα blockade alone show limited antitumor effect, therapies that combine blockade of this axis with other treatment agents, such as tumor-antigen specific antibodies, show superior tumor inhibition. Thus, we hypothesize that the addition of SIRPα inhibition to existing TNBC treatments (chemotherapy and Trop2-antibody drug conjugates (ADC)) will improve their treatment efficacy. Methods: To ascertain the impact of SIRPα inhibition combined with chemotherapy and Trop2-ADC, we utilized and validated a novel SIRPα KO mouse, along with SIRPα mAbs, in our previously utilized models of Triple-Negative Breast Cancer (TNBC) (Crosby et al., 2018). Using both in vitro and in vivo tumor models, we tested the therapeutic impact of SIRPα inhibition/blockade combined with different immunogenic chemotherapies (doxorubicin/cyclophosphamide) and Sacituzumab govitecan (SG) in TNBC. Results: After validating the loss of SIRPα in KO mice, we found that E0771 TNBC cells had comparable growth rates in WT and SIRPα KO mice. Similarly, we did not observe different anti-tumor responses to Doxorubicin between WT and SIRPα-KO mice. However, we observed more profound suppression of E0771 tumors after cyclophosphamide treatment in SIRPα KO mice than in WT mice. To evaluate the efficacy of SG in inducing antibody-dependent cellular phagocytosis (ADCP), we co-cultured SIRPα KO and WT mouse macrophages with a syngeneic mouse TNBC model (MM3MG-Trop2-WT). We found that SG promotes ADCP in WT macrophages, and SIRPα loss further increased this ADCP, suggesting the potential importance of antibody-mediated phagocytosis as a mechanism of action for SG. In vivo, we implanted human TNBC cells (MDA-MB-468) in mice and treated them with SG with and without SIRPα antibody blockade. These studies demonstrated an anti-tumor effect from SG that was potentially enhanced by SIRPα blockade, suggesting the clinical potential of this combination in TNBC. Conclusion: Our study demonstrates that the addition of SIRPα inhibition to chemotherapy or SG may promote tumor phagocytosis and stimulate stronger antitumor immunity in TNBC. These results support further investigation of SIRPα-targeting combination therapies for TNBC. Citation Format: Xingru Ma, Li-Chung Tsao, Tao Wang, Cong-Xiao Liu, Melissa Gajda, Xiao Yang, Gangjun Lei, Junping Wei, Zachary Hartman. Enhancing anti-tumor responses in triple-negative breast cancer by combining SIRPα inhibition with immunogenic chemotherapy or antibody-drug conjugates [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 3716.

Abstract 1176: Identification of circulating and spatial dynamics of immune cells response to to immune checkpoint inhibitors in triple-negative breast cancer at single-cell resolution

Abstract Background: Triple-negative breast cancer (TNBC) have had significantly worse survival outcome compared to other BC subtypes even though treatment strategies of TNBC have been advanced. The advent of immune checkpoint inhibitors (ICIs), especially pembrolizumab, a PD-1 inhibitor, has started to revolutionize TNBC treatment, showing encouraging effects in improving survival outcomes regardless of treatment settings. In neoadjuvant setting, pembrolizumab with cytotoxic chemotherapy achieved 13.6 % of pathologic complete response rate improvement and 36% of three-year event reduction. Therefore, pembrolizumab has highlighted new dimensions of TNBC's immunogenic characteristics. However, no immunogenic characteristics to predict the response of pembrolizumab have not been revealed. Methods: This study was designed as prospective, translational research for stage II or III TNBC patients scheduled for neoadjuvant chemotherapy with or without pembrolizumab followed by curative surgery. Tissue and blood samples were collected at baseline, 1 or 3 weeks after the first treatment initiation and curative surgery. We employed various single-cell and bulk RNA techniques for our multiomic analysis, including peripheral blood mononuclear cell (PBMC) single-cell RNA sequencing, T cell receptor sequencing (scTCR), high-resolution single-cell spatial transcriptomics (Xenium) targeting 380 genes, and bulk PBMC and tissue TCR analysis Results: From March 2023 to October 2023, 37 patients were enrolled in this study. Of 37 patients, we collected 36 blood and BC tissue samples at baseline, as well as 35 blood and 14 BC tissues at follow-up. These samples were analyzed and also compared with sex and age-matched healthy controls (n = 65). Of 37 patients, two patients were treated with only cytotoxic chemotherapy without pembrolizumab. We observed substantial increases in both systemic and localized immune responses, primarily marked by an upsurge in activated T cells and a decrease in regulatory T cells. A notable rise in TCR diversity post one week of treatment was followed by clonal expansion of activated T cells after three weeks in both blood and tissue. In addition, we observed a significant enrichment of pathways related to inflammatory response in classical monocytes following treatment. Conclusion: The findings from this study significantly enhance our understanding of the dynamics of circulating and local immune cells in TNBC, analyzed at a single-cell level with spatial information. These insights reveal how pembrolizumab alters the immune landscape and correlates these changes with treatment responses. Importantly, the data provide valuable indicators for predicting which TNBC patients are more likely to respond to neoadjuvant pembrolizumab therapy. Citation Format: Eun Seop Seo, Hae Hyun Jung, Kibyung Kim, Kyunghee Park, Eun Young Ko, Byung Joo Chae, Jeong Eon Lee, Eun Yoon Cho, Ji-Yeon Kim, Woong-Yang Park. Identification of circulating and spatial dynamics of immune cells response to to immune checkpoint inhibitors in triple-negative breast cancer at single-cell resolution [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 1176.

YAP1-induced RBM24 promotes the tumorigenesis of triple-negative breast cancer through the β-catenin pathway.

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype and refractory to current treatments. RBM24 is an RNA-binding protein and shows the ability to regulate tumor progression in multiple cancer types. However, its role in TNBC is still unclear. In this study, we analyzed publicly available profiling data from TNBC tissues and cells. Loss- and gain-of-function experiments were performed to determine the function of RBM24 in TNBC cells. The mechanism for RBM24 action in TNBC was investigated. RBM24 was deregulated in TNBC tissues and TNBC cells with depletion of SIPA1, YAP1, or ARID1A, three key regulators of TNBC. Compared to MCF10A breast epithelial cells, TNBC cells had higher levels of RBM24. Knockdown of RBM24 inhibited TNBC cell proliferation, colony formation, and tumorigenesis, while overexpression of RBM24 promoted aggressive phenotype in TNBC cells. YAP1 overexpression induced the expression of RBM24 and the RBM24 promoter-driven luciferase reporter. YAP1 was enriched at the promoter region of RBM24. Overexpression of RBM24 increased β-catenin-dependent transcriptional activity. Most importantly, knockdown of CTNNB1 rescued RBM24 aggressive phenotype in TNBC cells. Collectively, the YAP1/RBM24/β-catenin axis plays a critical role in driving TNBC progression. RBM24 may represent a novel therapeutic target for TNBC treatment.

Comparative study of weekly and three-weekly neoadjuvant carboplatin in triple-negative breast cancer: retrospective analysis in real-world settings.

Tri-weekly carboplatin is an established neoadjuvant treatment for triple-negative breast cancer, enhancing pathological complete response (pCR) and overall survival. This study explores if weekly carboplatin provides lower toxicity and comparable pCR rates. A retrospective multicenter study (January 2021 to March 2023) compares outcomes of weekly and tri-weekly carboplatin. Among 104 participants, 60% received weekly and 40% tri-weekly treatments. Weekly administration had fewer discontinuations (56.5 vs. 70.7%, p=0.154). Both schedules exhibited similar overall toxicity (p=0.087), with slightly higher grade 3-4 toxicity in the tri-weekly group (56.1 vs. 48.4%, p=0.126). Hematological toxicity was comparable, but the weekly group experienced more diarrhea (p=0.432) and asthenia (p=0.012). Weekly treatment correlated with more frequent breast-conserving surgeries (p=0.004). pCR rates were 50% with weekly and 61% with tri-weekly regimens (p=0.186). Weekly carboplatin exhibited comparable toxicity, a trend toward fewer interruptions, and similar pCR rates. Prospective studies are essential for validating these findings.

Mammary tissue-derived extracellular matrix hydrogels reveal the role of irradiation in driving a pro-tumor and immunosuppressive microenvironment

Radiation therapy (RT) is essential for triple negative breast cancer (TNBC) treatment. However, patients with TNBC continue to experience recurrence after RT. The role of the extracellular matrix (ECM) of irradiated breast tissue in tumor recurrence is still unknown. In this study, we evaluated the structure, molecular composition, and mechanical properties of irradiated murine mammary fat pads (MFPs) and developed ECM hydrogels from decellularized tissues (dECM) to assess the effects of RT-induced ECM changes on breast cancer cell behavior. Irradiated MFPs were characterized by increased ECM deposition and fiber density compared to unirradiated controls, which may provide a platform for cell invasion and proliferation. ECM component changes in collagens I, IV, and VI, and fibronectin were observed following irradiation in both MFPs and dECM hydrogels. Encapsulated TNBC cell proliferation and invasive capacity was enhanced in irradiated dECM hydrogels. In addition, TNBC cells co-cultured with macrophages in irradiated dECM hydrogels induced M2 macrophage polarization and exhibited further increases in proliferation. Our study establishes that the ECM in radiation-damaged sites promotes TNBC invasion and proliferation as well as an immunosuppressive microenvironment. This work represents an important step toward elucidating how changes in the ECM after RT contribute to breast cancer recurrence.

ROS mediated Cu[Fe(CN)5NO] nanoparticles for triple negative breast cancer: A detailed study in preclinical mouse model

Triple negative breast cancer (TNBC) is an aggressive form of tumor, more prevalent in younger women resulting in poor survival rate (2nd in cancer deaths) because of its asymptomatic existence. The most popular and convenient approach for the treatment of TNBC is chemotherapy which is associated with several limitations. Considering the importance of nanotechnology in health care system, in the present manuscript, we have designed and developed a simple, efficient, cost effective, and ecofriendly method for the synthesis of copper nitroprusside analogue nanoparticles (Cu[Fe(CN)5NO] which is abbreviated as CuNPANP that may be the potential anti-cancer nanomedicine for the treatment of TNBC. Copper (present in CuNPANP) is used because of its affordability, nutritional value and various biomedical applications. The CuNPANP are thoroughly characterized using several analytical techniques. The in vitro cell viability (in normal cells) and the ex vivo hemolysis assay reveal the biocompatible nature of CuNPANP. The anti-cancer activity of the CuNPANP is established in TNBC cells (MDA-MB-231 and 4T1) through several in vitro assays along with plausible mechanisms. The intraperitoneal administration of CuNPANP in orthotopic breast tumor model by transplanting 4T1 cells into the mammary fat pad of BALB/c mouse significantly inhibits the growth of breast carcinoma as well as increases the survival time of tumor-bearing mice. These results altogether potentiate the anti-cancer efficacy of CuNPANP as a smart therapeutic nanomedicine for treating TNBC in near future after bio-safety evaluation in large animals.

STK32C modulates doxorubicin resistance in triple-negative breast cancer cells via glycolysis regulation.

Understanding the mechanisms underlying doxorubicin resistance in triple-negative breast cancer (TNBC) holds paramount clinical significance. In our study, we investigate the potential of STK32C, a little-explored kinase, to impact doxorubicin sensitivity in TNBC cells. Our findings reveal elevated STK32C expression in TNBC specimens, associated with unfavorable prognosis in doxorubicin-treated TNBC patients. Subsequent experiments highlighted that STK32C depletion significantly augmented the sensitivity of doxorubicin-resistant TNBC cells to doxorubicin. Mechanistically, we unveiled that the cytoplasmic subset of STK32C plays a pivotal role in mediating doxorubicin sensitivity, primarily through the regulation of glycolysis. Furthermore, the kinase activity of STK32C proved to be essential for its mediation of doxorubicin sensitivity, emphasizing its role as a kinase. Our study suggests that targeting STK32C may represent a novel therapeutic approach with the potential to improve doxorubicin's efficacy in TNBC treatment.

Antineoplastic effect of compounds C14 and P8 on TNBC and radioresistant TNBC cells by stabilizing the K-Ras4BG13D/PDE6δ complex.

Breast cancer (BC) is the leading cause of cancer-related deaths among women, with triple-negative breast cancer (TNBC) representing one of the most aggressive and treatment-resistant subtypes. In this study, we aimed to evaluate the antitumor potential of C14 and P8 molecules in both TNBC and radioresistant TNBC cells. These compounds were chosen for their ability to stabilize the complex formed by the overactivated form of K-Ras4BG13D and its membrane transporter (PDE6δ). The antitumor potential of C14 and P8 was assessed using TNBC cell lines, MDA-MB-231, and the radioresistant derivative MDA-MB-231RR, both carrying the K-Ras4B> G13D mutation. We investigated the compounds' effects on K-Ras signaling pathways, cell viability, and tumor growth in vivo. Western blotting analysis determined the negative impact of C14 and P8 on the activation of mutant K-Ras signaling pathways in MDA-MB-231 and MDA-MB-231RR cells. Proliferation assays demonstrated their efficacy as cytotoxic agents against K-RasG13D mutant cancer cells and in inducing apoptosis. Clonogenic assays proven their ability to inhibit TNBC and radioresistant TNBC cell clonogenicity. In In vivo studies, C14 and P8 inhibited tumor growth and reduced proliferation, angiogenesis, and cell cycle progression markers. These findings suggest that C14 and P8 could serve as promising adjuvant treatments for TNBC, particularly for non-responders to standard therapies. By targeting overactivated K-Ras and its membrane transporter, these compounds offer potential therapeutic benefits against TNBC, including its radioresistant form. Further research and clinical trials are warranted to validate their efficacy and safety as novel TNBC treatments.

Local Production of Acute Phase Proteins: A Defense Reaction of Cancer Cells to Injury with Focus on Fibrinogen.

This review is intended to demonstrate that the local production of acute phase proteins (termed local acute phase response (lAPR)) and especially fibrin/fibrinogen (FN) is a defense mechanism of cancer cells to therapy, and inhibition of the lAPR can augment the effectiveness of cancer therapy. Previously we detected a lAPR accompanying tumor cell death during the treatment of triple-negative breast cancer (TNBC) with modulated electro-hyperthermia (mEHT) in mice. We observed a similar lAPR in in hypoxic mouse kidneys. In both models, production of FN chains was predominant among the locally produced acute phase proteins. The production and extracellular release of FN into the tumor microenvironment is a known method of self-defense in tumor cells. We propose that the lAPR is a new, novel cellular defense mechanism like the heat shock response (HSR). In this review, we demonstrate a potential synergism between FN inhibition and mEHT in cancer treatment, suggesting that the effectiveness of mEHT and chemotherapy can be enhanced by inhibiting the HSR and/or the lAPR. Non-anticoagulant inhibition of FN offers potential new therapeutic options for cancer treatment.

Multifunctional iron-apigenin nanocomplex conducting photothermal therapy and triggering augmented immune response for triple negative breast cancer

Triple negative breast cancer (TNBC) presents a formidable challenge due to its low sensitivity to many chemotherapeutic drugs and a relatively low overall survival rate in clinical practice. Photothermal therapy has recently garnered substantial interest in cancer treatment, owing to its swift therapeutic effectiveness and minimal impact on normal cells. Metal-polyphenol nanostructures have recently garnered significant attention as photothermal transduction agents due to their facile preparation and favorable photothermal properties. In this study, we employed a coordinated approach involving Fe3+ and apigenin, a polyphenol compound, to construct the nanostructure (nFeAPG), with the assistance of β-CD and DSPE-PEG facilitating the formation of the complex nanostructure. In vitro research demonstrated that the formed nFeAPG could induce cell death by elevating intracellular oxidative stress, inhibiting antioxidative system, and promoting apoptosis and ferroptosis, and near infrared spectrum irradiation further strengthen the therapeutic outcome. In 4T1 tumor bearing mice, nFeAPG could effectively accumulate into tumor site and exhibit commendable control over tumor growth. Futher analysis demonstrated that nFeAPG ameliorated the suppressed immune microenvironment by augmenting the response of DC cells and T cells. This study underscores that nFeAPG encompasses a multifaceted capacity to combat TNBC, holding promise as a compelling therapeutic strategy for TNBC treatment.

FZD7-Targeted Nanoparticles to Enhance Doxorubicin Treatment of Triple-Negative Breast Cancer.

Doxorubicin (DOX) is a chemotherapy agent commonly used to treat triple-negative breast cancer (TNBC), but it has insufficient efficacy against the disease and considerable toxicity due to its off-target delivery. To improve the specificity of DOX for TNBC, we encapsulated it in poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) coated with antibodies against Frizzled7 (FZD7), a receptor that is overexpressed on TNBC cells and which is a key activator of the Wnt signaling pathway. In vitro studies show that DOX encapsulation does not hinder its ability to localize to the nucleus in human TNBC cell cultures and that DOX delivered via NPs induces apoptosis and DNA damage via H2A.X phosphorylation to the same degree as freely delivered DOX. FZD7-targeted NPs delivering DOX caused significantly greater inhibition of metabolic activity and led to a smaller cell population following treatment when compared to freely delivered DOX or DOX-loaded NPs coated only with poly(ethylene glycol) (PEG). The FZD7 antibodies additionally provided significant levels of Wnt pathway inhibition, as demonstrated by an increase in β-catenin phosphorylation, indicative of β-catenin destruction and downregulation. These results show that FZD7-targeted platforms have great promise for improving the therapeutic window of otherwise toxic chemotherapies like DOX in TNBC and other cancers that display the overexpression of FZD7 receptors.

Acidic/hypoxia dual-alleviated nanoregulators for enhanced treatment of tumor chemo-immunotherapy

Chemotherapy plays a crucial role in triple-negative breast cancer (TNBC) treatment as it not only directly kills cancer cells but also induces immunogenic cell death. However, the chemotherapeutic efficacy was strongly restricted by the acidic and hypoxic tumor environment. Herein, we have successfully formulated PLGA-based nanoparticles concurrently loaded with doxorubicin (DOX), hemoglobin (Hb) and CaCO3 by a CaCO3-assisted emulsion method, aiming at the effective treatment of TNBC. We found that the obtained nanomedicine (DHCaNPs) exhibited effective drug encapsulation and pH-responsive drug release behavior. Moreover, DHCaNPs demonstrated robust capabilities in neutralizing protons and oxygen transport. Consequently, DHCaNPs could not only serve as oxygen nanoshuttles to attenuate tumor hypoxia but also neutralize the acidic tumor microenvironment (TME) by depleting lactic acid, thereby effectively overcoming the resistance to chemotherapy. Furthermore, DHCaNPs demonstrated a notable ability to enhance antitumor immune responses by increasing the frequency of tumor-infiltrating effector lymphocytes and reducing the frequency of various immune-suppressive cells, therefore exhibiting a superior efficacy in suppressing tumor growth and metastasis when combined with anti-PD-L1 (αPD-L1) immunotherapy. In summary, this study highlights that DHCaNPs could effectively attenuate the acidic and hypoxic TME, offering a promising strategy to figure out an enhanced chemo-immunotherapy to benefit TNBC patients.

Cyclin-dependent kinase inhibitors enhance programmed cell death protein 1 immune checkpoint blockade efficacy in triple-negative breast cancer by affecting the immune microenvironment.

Clinical studies on programmed death-ligand 1 (PD-L1) immune checkpoint inhibitors for treating triple-negative breast cancer (TNBC) have shown unsatisfactory efficacy due to low tumor-infiltrating lymphocyte (TIL) levels. Inhibitors targeting cyclin-dependent kinase (CDK) proteins can affect the immune microenvironment, increase TIL levels, and promote antitumor immunity, thus providing a new direction for TNBC treatment strategies. The authors tested three CDK inhibitors on the TNBC cell lines MDA-MB-231 and 4T1 and validated their antitumor effects and impact on the immune microenvironment using multiple detection methods. They verified the efficacy and immune-related mechanisms of different combination therapy experiments in a 4T1 cell-transplanted BALB/c mouse model. Treatment with CDK inhibitors for 72 hours inhibited cell proliferation, clone formation, migration, and cell-cycle arrest and induced apoptosis in human breast cancer MDA-MB-231 cells and mouse breast cancer 4T1 cells. CDK inhibitors suppressed DNA methylation by downregulating DNMT1, DNMT3a, and DNMT3b expression. These three inhibitors promoted the secretion of various chemokines, enhanced tumor cell antigen presentation, and increased PD-L1 expression. CDK inhibitors improved the efficacy of immunotherapy in animal models and increased TIL levels. Combination therapy with CDK and PD-L1 immune checkpoint inhibitors affects the immune microenvironment, promotes antitumor immunity, and improves the efficacy of immunotherapy for TNBC.

Precise nano-system-based drug delivery and synergistic therapy against androgen receptor-positive triple-negative breast cancer

Targeting androgen receptor (AR) has shown great therapeutic potential in triple-negative breast cancer (TNBC), yet its efficacy remains unsatisfactory. Here, we aimed to identify promising targeted agents that synergize with enzalutamide, a second-generation AR inhibitor, in TNBC. By using a strategy for screening drug combinations based on the Sensitivity Index (SI), we found that MK-8776, a selective checkpoint kinase1 (CHK1) inhibitor, showed favorable synergism with enzalutamide in AR-positive TNBC. The combination of enzalutamide and MK-8776 was found to exert more significant anti-tumor effects in TNBC than the single application of enzalutamide or MK-8776, respectively. Furthermore, a nanoparticle-based on hyaluronic acid (HA)-modified hollow-manganese dioxide (HMnO2), named HMnE&M@H, was established to encapsulate and deliver enzalutamide and MK-8776. This HA-modified nanosystem managed targeted activation via pH/glutathione responsiveness. HMnE&M@H repressed tumor growth more obviously than the simple addition of enzalutamide and MK-8776 without a carrier. Collectively, our study elucidated the synergy of enzalutamide and MK-8776 in TNBC and developed a novel tumor-targeted nano drug delivery system HMnE&M@H, providing a potential therapeutic approach for the treatment of TNBC.

Assessment of TUFT1 and Rac1-GTP levels in triple-negative breast cancer patients: clinical and pathological correlations.

The primary goal of this study was to investigate the expressions of TUFT1 (Tuftelin) and Rac1-GTP in the cancerous tissues of individuals with triple-negative breast cancer (TNBC). Additionally, we aimed to explore the correlation between TUFT1 and Rac1-GTP expressions and examine the associations of TUFT1 and Rac1-GTP expressions with the clinical and pathological indicators of the patients. Ninety-six patients diagnosed with TNBC, scheduled for surgery between May 2022 and November 2022, were enrolled in this study. Cancerous tissue specimens were collected from these patients, and immunohistochemistry was employed to evaluate the levels of TUFT1 and Rac1-GTP expressions in the cancerous tissues. Subsequent to data collection, a comprehensive analysis was conducted to examine the correlation between TUFT1 and Rac1-GTP expressions. Furthermore, we sought to assess the associations of TUFT1 and Rac1-GTP expressions with the clinical and pathological indicators of the patients. The TUFT1 protein was expressed in both the membrane and cytoplasm of TNBC cancer cells, with notably higher expression observed in the cytoplasm. Rac1-GTP was primarily expressed in the cytoplasm. There was a positive correlation between the levels of TUFT1 and Rac1-GTP expressions (χ2 = 9.816, P < 0.05). The levels of TUFT1 and Rac1-GTP protein expressions showed no correlation with patient age (χ2 = 2.590, 2.565, P > 0.05); however, they demonstrated a positive correlation with tumor size (χ2 = 5.592,5.118), histological grading (χ2 = 6.730, 5.443), and lymph node metastasis (χ2 = 8.221, 5.180) (all with a significance level of P < 0.05). A significant correlation was identified between the levels of TUFT1 and Rac1-GTP expressions in the cancerous tissues of patients with TNBC, suggesting a close association with the progression of TNBC. The two molecules play significant roles in facilitating an early diagnosis and treatment of TNBC.

Zirconium-containing nanoscale coordination polymers for positron emission tomography and fluorescence-guided cargo delivery to triple-negative breast tumors

Nanoscale coordination polymer (NCP) is a class of hybrid materials formed by self-assembly of metal ions and organic ligands through coordination. The applications of NCP in biomedicine are quite extensive due to the diversity choice of metal ions and organic ligands. Here we designed Zr-P1 NCP based on Zr4+ selected as metal ion nodes and tetrakis(4-carboxyphenyl) ethylene as bridging ligands. Zr-P1 NCP was modified with functionalized pyrene derived polyethylene glycol (Py-PAA-PEG-Mal) on the surface and further conjugated with cRGD for active targeting of integrin αvβ3 overexpressed in triple-negative breast cancer. Doxorubicin was loaded on Zr-P1 NCP with encapsulation efficiency up to 22 % for the treatment of triple negative breast cancer. 89Zr-P1 NCP can be used for in vivo tumor imaging due to the fluorescence properties resulting from the enhanced aggregation-induced Emission (AIE) behavior of P1 ligands and its positron emission tomography (PET) capability. Cellular evaluation indicated that the functionalized Zr-P1@PEG-RGD presented a good function for tumor cell targeting imaging and doxorubicin could be targeted to triple negative breast cancer when it was loaded onto Zr-P1@PEG-RGD, which corroborated with the in vivo results. In summary, 89Zr-P1@PEG-RGD can serve as a biocompatible nanoplatform for fluorescence and PET image-guided cargo delivery. Statement of SignificanceNanoscale coordination polymer (NCP) is a class of hybrid materials formed by self-assembly of metal ions and organic ligands through coordination. The diversity of available metals and ligand structures upon NCP synthesis plays an advantage in establishing multimodal imaging platforms. Here we designed 89Zr-P1@PEG-RGD NCP based on Zr4+ selected as metal ion nodes and tetrakis(4-carboxyphenyl) ethylene as bridging ligands. 89Zr-P1@PEG-RGD nanomaterials have positron emission tomography (PET) capability due to the incorporation of zirconium-89, which can be used for in vivo tumor imaging with high sensitivity. The chemotherapeutic drug DOX was loaded on Zr-P1 NCP for the treatment of triple-negative breast cancer, and dual modality imaging can provide visual guidance for drug delivery.

Efficacy of Cold Atmospheric Plasma vs. Chemotherapy in Triple-Negative Breast Cancer: A Systematic Review.

Breast cancer is a growing disease, with a high worldwide incidence and mortality rate among women. Among the various types, the treatment of triple-negative breast cancer (TNBC) remains a challenge. Considering the recent advances in cold atmospheric plasma (CAP) cancer research, our goal was to evaluate efficacy data from studies based on chemotherapy and CAP in TNBC cell lines and animal models. A search of the literature was carried out in the PubMed, Web of Science, Cochrane Library, and Embase databases. Of the 10,999 studies, there were fifty-four in vitro studies, three in vivo studies, and two in vitro and in vivo studies included. MDA-MB-231 cells were the most used. MTT, MTS, SRB, annexin-V/propidium iodide, trypan blue, and clonogenic assay were performed to assess efficacy in vitro, increasing the reliability and comprehensiveness of the data. There was found to be a decrease in cell proliferation after both chemotherapy and CAP; however, different protocol settings, including an extensive range of drug doses and CAP exposure times, were reported. For both therapies, a considerable reduction in tumor volume was observed in vivo compared with that of the untreated group. The treatment of TNBC cell lines with CAP proved successful, with apoptosis emerging as the predominant type of cellular death. This systematic review presents a comprehensive overview of the treatment landscape in chemotherapy and CAP regarding their efficacy in TNBC cell lines.

Nitric oxide nano-reactor DNMF/PLGA enables tumor vascular microenvironment and chemo-hyperthermia synergetic therapy

BackgroundBreast cancer ranks first among malignant tumors, of which triple-negative breast cancer (TNBC) is characterized by its highly invasive behavior and the worst prognosis. Timely diagnosis and precise treatment of TNBC are substantially challenging. Abnormal tumor vessels play a crucial role in TNBC progression and treatment. Nitric oxide (NO) regulates angiogenesis and maintains vascular homeostasis, while effective NO delivery can normalize the tumor vasculature. Accordingly, we have proposed here a tumor vascular microenvironment remodeling strategy based on NO-induced vessel normalization and extracellular matrix collagen degradation with multimodality imaging-guided nanoparticles against TNBC called DNMF/PLGA.ResultsNanoparticles were synthesized using a chemotherapeutic agent doxorubicin (DOX), a NO donor L-arginine (L-Arg), ultrasmall spinel ferrites (MnFe2O4), and a poly (lactic-co-glycolic acid) (PLGA) shell. Nanoparticle distribution in the tumor was accurately monitored in real-time through highly enhanced magnetic resonance imaging and photoacoustic imaging. Near-infrared irradiation of tumor cells revealed that MnFe2O4 catalyzes the production of a large amount of reactive oxygen species (ROS) from H2O2, resulting in a cascade catalysis of L-Arg to trigger NO production in the presence of ROS. In addition, DOX activates niacinamide adenine dinucleotide phosphate oxidase to generate and supply H2O2. The generated NO improves the vascular endothelial cell integrity and pericellular contractility to promote vessel normalization and induces the activation of endogenous matrix metalloproteinases (mainly MMP-1 and MMP-2) so as to promote extravascular collagen degradation, thereby providing an auxiliary mechanism for efficient nanoparticle delivery and DOX penetration. Moreover, the chemotherapeutic effect of DOX and the photothermal effect of MnFe2O4 served as a chemo-hyperthermia synergistic therapy against TNBC.ConclusionThe two therapeutic mechanisms, along with an auxiliary mechanism, were perfectly combined to enhance the therapeutic effects. Briefly, multimodality image-guided nanoparticles provide a reliable strategy for the potential application in the fight against TNBC.Graphical