Pathogenesis of Triple-Negative Breast Cancer

Real-world perioperative treatment patterns and economic burden of recurrence in early-stage HER2-negative breast cancer: a SEER-Medicare study

AIM

This study aimed to describe treatment patterns and quantify the economic impact of recurrence in early-stage human epidermal growth factor receptor 2 (HER2)-negative breast cancer (BC).

MATERIALS & METHODS

Medicare beneficiaries with stages I-III HER2-negative BC and lumpectomy or partial/total mastectomy were identified from SEER-Medicare data (2010-2019). Perioperative therapies were reported in the neoadjuvant and adjuvant setting. Locoregional recurrence and distant metastasis were identified using a claims-based algorithm developed with clinical input and consisting of a diagnosis-based and treatment-based indicator. All-cause and BC-related healthcare resource utilization (HRU) per-patient-month and monthly healthcare costs were estimated from the recurrence date for patients with recurrence and from an imputed index date for patients without recurrence using frequency matching. HRU and costs were compared between groups stratified by hormone receptor-positive (HR+) or triple negative BC (TNBC) using multivariable regression models.

RESULTS

Of 28,655 patients, 8.5% experienced recurrence, 90.4% had HR+ disease, and 5.6% received neoadjuvant therapy. Relative to patients without recurrence, patients with recurrence had more advanced disease (stage II/III: 73.7% vs. 34.0%) and higher-grade tumors (Grade 3/4: 40.6% vs. 18.0%) at diagnosis. Recurrence in HR+/HER2-negative BC and TNBC was associated with higher rates of all-cause hospitalizations (incidence rate ratio [IRR]: 2.84 and 3.65), emergency department (ED) visits (IRR: 1.75 and 2.00), and outpatient visits (IRR: 1.46 and 1.55; all p < 0.001). Similarly, recurrence was associated with higher rates of BC-related HRU, particularly for ED visits in HR+/HER2-negative BC (IRR: 4.24; p < 0.001) and hospitalizations in TNBC (IRR: 11.71; p < 0.001). Patients with HR+/HER2-negative BC and TNBC recurrence incurred higher monthly all-cause (cost difference [CD]: $3988 and $4651) and BC-related healthcare costs (CD: $3743 and $5819).

CONCLUSIONS

Our findings highlight the considerable economic burden of recurrence in early-stage HER2-negative BC and underscore the unmet need for optimization of therapies that reduce recurrence in this population.

A carrier-free ultrasound-responsive polyphenol nanonetworks with enhanced sonodynamic-immunotherapy for synergistic therapy of breast cancer

Sonodynamic therapy (SDT) is an efficient non-invasive strategy for treating breast cancer. However, the therapeutic efficacy of SDT is greatly limited by various defense mechanisms in the tumor microenvironment, particularly the overexpression of B-cell lymphoma-2 (Bcl-2). In this study, based on drug self-delivery systems, a carrier-free ultrasound-responsive polyphenol nanonetwork (GTC) was developed to enhance SDT by inhibiting Bcl-2. A one-pot method, involving the interaction of the polyphenolic Bcl-2 inhibitor gossypol (GOS), transferrin, and the sonosensitizer chlorin e6 (Ce6), was used to synthesize the GTC. The GTC was efficiently internalized by MDA-MB-231 and 4T1 cells through specific binding to transferrin receptors, and no external carriers were needed. After cellular internalization, GOS increased the lethality of Ce6-mediated SDT by reducing the expression of the Bcl-2 protein, which caused multiple toxic effects. RNA-seq analysis confirmed the transcriptomic alterations in oxidative stress and apoptotic pathways induced by the GTC nanosystem. In vivo studies revealed that GOS-assisted SDT not only eliminated tumors through sonodynamic effects and triggered immunogenic cell death but also enhanced sono-immunotherapy, thus effectively suppressing distant tumors and metastasis. This study might provide insights into carrier-free nanomedicines for SDT-based synergistic tumor therapy.

Structural optimization and characterization of highly potent and selective STAT3 inhibitors for the treatment of triple negative breast cancer

Effective targeted treatments for triple-negative breast cancer (TNBC), which has the worst prognosis among various types of breast cancer, are lacking owing to its clinical heterogeneity and malignant nature. STAT3, a key transcription factor, regulates multiple physiological functions. Aberrant activation of STAT3 plays a pivotal role in the initiation and progression of TNBC and is closely associated with a poor prognosis. Therefore, targeting STAT3 is a promising potential therapeutic approach for TNBC. In this study, we further optimized the core structure of 6f, which our research group previously identified as a STAT3 inhibitor and treatment for osteosarcoma, to identify additional potential STAT3 inhibitors for TNBC treatment. We identified WR-S-462 as a high-binding affinity inhibitor of STAT3 that effectively suppresses its phosphorylation and biological functions in vitro. Notably, WR-S-462 significantly inhibits TNBC growth and metastasis in a dose-dependent manner, providing robust evidence for its potential as a clinical intervention for TNBC.

METTL3/IGF2BP1 promotes the development of triple-negative breast cancer by mediating m6A methylation modification of PRMT7

BACKGROUND

PRMT7 is upregulated in breast cancer and promotes tumor metastasis. Here we aimed to explore the function and mechanism of PRMT7 in triple-negative breast cancer (TNBC).

METHODS

The expression of PRMT7, METTL3 and IGF2BP1 was detected by immunohistochemistry (IHC), qRT-PCR and western blot. Cell viability and proliferation were measured using MTT and EdU assay. Flow cytometry and TUNEL assays were used to evaluate apoptosis. Invasion and migration were assessed by transwell and wound healing assays, respectively. Glucose consumption and lactate production were measured to assess glycolysis. In addition, the interaction between METTL3 and PRMT was verified by methylated RNA immunoprecipitation. The roles of METTL3 and PRMT in vivo were investigated through a xenograft model.

RESULTS

PRMT7 was upregulated in TNBC tissues and cells, and the knockdown of PRMT7 inhibited cell proliferation, invasion, migration and glycolysis, but induced apoptosis in TNBC cells. METTL3/IGF2BP1 enhanced PRMT7 expression by mediating the m6A methylation modification of PRMT7. Besides, METTL3 knockdown suppressed the progression of TNBC cells and regulated the WNT/β-catenin pathway via PRMT7. Moreover, silencing METTL3 restrained TNBC tumor growth in vivo through regulating PRMT7.

CONCLUSION

METTL3/IGF2BP1 facilitates the progression of TNBC by mediating m6A methylation modification of PRMT7.

Targeted nanoparticle delivery system for tumor-associated macrophage reprogramming to enhance TNBC therapy

Triple-negative breast cancer (TNBC) poses as a daunting and intricate manifestation of breast cancer, highlighted by few treatment options and a poor outlook. The crucial element in fostering tumor growth and immune resistance is the polarization of tumor-associated macrophages (TAMs) into the M2 state within the tumor microenvironment (TME). To address this, we developed M2 targeting peptide-chitosan-curcumin nanoparticles (M2pep-Cs-Cur NPs), a targeted delivery system utilizing chitosan (Cs) as a carrier, curcumin (Cur) as a therapeutic agent, and targeting peptides for specificity. These NPs effectively inhibited TNBC cell proliferation (~ 70%) and invasion (~ 70%), while increasing the responsiveness of tumors to anti-PD-L1 treatment (~ 50% survival enhancement) in vitro and in vivo. Bioinformatics analysis suggested that Cur modulates TAM polarization by influencing key genes such as COX-2, offering insights into its underlying mechanisms. This study highlights the potential of M2pep-Cs-Cur NPs to reverse M2 polarization in TAMs, providing a promising targeted therapeutic strategy to overcome immunotherapy resistance and improve TNBC outcomes.

A dual thermo/pH-sensitive hydrogel as 5-Fluorouracil carrier for breast cancer treatment

Intelligent hydrogels are promising in constructing scaffolds for the controlled delivery of drugs. Here, a dual thermo- and pH-responsive hydrogel called PCG [poly ( N -isopropyl acrylamide-co-itaconic acid)/chitosan/glycerophosphate (PNI/CS/GP)] was established as the carrier of 5-fluorouracil (5-FU) for triple-negative breast cancer (TNBC) treatment. The PCG hydrogel was fabricated by blending synthesized [poly ( N -isopropyl acrylamide-co-itaconic acid), pNIAAm-co-IA, PNI] with CS in the presence of GP as a crosslinking agent. The interaction between PCG hydrogel compositions was characterized by Fourier transforms infrared, NMR spectroscopy, and scanning electron microscopy. The PCG hydrogel presented an interconnected and porous structure with similar pore size, rapid swelling/deswelling rate in response to both temperature and pH change, and biocompatibility, upon which it was proposed as a great drug carrier. 5-FU had a dual thermo- and pH-responsive controlled release behavior from the PCG hydrogel and displayed an accelerated release rate in an acidic pH environment than in a neutral pH condition. The application of 5-FU-loaded PCG hydrogel exhibited a more promoted anticancer activity than 5-FU against the growth of TNBC cells both in vitro and in vivo . The outcomes suggested that the PCG hydrogel could be an excellent platform for local drug-delivery systems in the clinical therapy of TNBC.

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.

The emerging landscape of small nucleolar RNA host gene 10 in cancer mechanistic insights and clinical relevance

Small nucleolar RNA host gene 10 (SNHG10) is a newly recognized long non-coding RNA (lncRNA) with significant implications in cancer biology. Abnormal expression of SNHG10 has been observed in various solid tumors and hematological malignancies. Research conducted in vivo and in vitro has revealed that SNHG10 plays a pivotal role in numerous biological processes, including cell proliferation, apoptosis, invasion and migration, drug resistance, energy metabolism, immune evasion, as well as tumor growth and metastasis. SNHG10 regulates tumor development through several mechanisms, such as competing with microRNA (miRNA) for binding sites, modulating various signaling pathways, influencing transcriptional activity, and affecting epigenetic regulation. The diverse biological functions and intricate mechanisms of SNHG10 highlight its considerable clinical relevance, positioning it as a potential pan-cancer biomarker and therapeutic target. This review aims to summarize the role of SNHG10 in tumorigenesis and cancer progression, clarify the molecular mechanisms at play, and explore its clinical significance in cancer diagnosis and prognosis prediction, along with its therapeutic potential.

Molecular mechanism of ZC3H13 -mediated ferroptosis in doxorubicin resistance of triple negative breast cancer

BACKGROUND

Triple negative breast cancer (TNBC) continues to be the most aggressive subtype of breast cancer that frequently develops resistance to chemotherapy. Doxorubicin (DOX) belongs to the anthracycline chemical class of the drug and is one of the widely used anticancer drugs. This study investigates the mechanism of m6A methyltransferase ZC3H13 in DOX resistance of TNBC.

METHODS

ZC3H13, KCNQ1OT1, and TRABD expressions in TNBC tissues or cells were detected by RT-qPCR or Western blot. The effect of ZC3H13 on DOX resistance of TNBC cells was evaluated by CCK-8, clone formation, and EdU staining. RIP was performed to analyze the enrichment of YTHDF2 or m6A on KCNQ1OT1. RIP and RNA pull-down verified the binding between KCNQ1OT1 and MLL4. The enrichment of MLL or H3K9me1/2/3 on TRABD promoter was analyzed by ChIP. A nude mouse xenograft tumor model was established to verify the mechanism in vivo.

RESULTS

ZC3H13 was poorly expressed in TNBC, and its expression further decreased in drug-resistant cells. Overexpression of ZC3H13 decreased the IC50 of drug-resistant TNBC cells to DOX, repressed proliferation, and induced ferroptosis. Mechanistically, ZC3H13-mediated m6A modification reduced the transcriptional stability of KCNQ1OT1 and inhibited its expression in a YTHDF2-dependent manner. KCNQ1OT1 enhanced the enrichment of H3K4me1/2/3 on TRABD promoter by recruiting MLL4, thus increasing TRABD expression. ZC3H13 induced ferroptosis by inhibiting KCNQ1OT1/TRABD, thereby restraining the growth of DOX-treated tumors in vivo.

CONCLUSION

ZC3H13-mediated m6A modification reduces DOX resistance in TNBC by promoting ferroptosis via KCNQ1OT1/TRABD axis.

Mesenchymal stem cells modulate breast cancer progression through their secretome by downregulating ten-eleven translocation 1

Mesenchymal stem cells (MSCs) have emerged as crucial players within the tumor microenvironment (TME), contributing through their paracrine secretome. Depending on the context, the MSC-derived secretome can either support or inhibit tumor growth. This study investigates the role of MSC-derived secretome in modulating breast cancer (BC) cell behavior, with a focus on ten-eleven translocation 1 (TET1), a DNA demethylase with known oncogenic properties in triple-negative breast cancer (TNBC). We first isolated and characterized human bone marrow-derived MSCs, and then assessed the impact of their secretome on BC cells. Treatment with the MSC-derived secretome significantly inhibited the proliferation and migration of both MDA-MB-231 and MCF-7 BC cell lines, resulting in reduced cell viability and migration rates compared to control cells. Western blot analyses revealed downregulation of Cyclin D1 and c-Myc, along with decreased expression of N-cadherin and increased expression of E-cadherin, indicating potential inhibition of the epithelial-to-mesenchymal transition. Differential gene expression analyses highlighted TET1 as significantly upregulated in TNBC tissues compared to normal samples. Further experiments confirmed that the MSC-derived secretome downregulated TET1 expression in BC cells, as evidenced by RT-qPCR and western blot analyses. To explore TET1's functional role, we silenced TET1 with siRNAs, observing cell cycle arrest and enhanced apoptosis-effects that mirrored those seen with MSC-secretome treatment. Notably, TET1 knockdown also increased MDA-MB-231 cell sensitivity to cisplatin, suggesting a role for TET1 in chemoresistance. These findings provide insight into the ability of MSCs to modulate BC cell progression through their secretome, highlighting the involvement of TET1 downregulation in inhibiting BC cell progression and enhancing cisplatin chemosensitivity. The MSC-derived secretome thus holds promise as an innovative, cell-free therapeutic approach in BC treatment.

Sphingosine kinase 2 in cancer: A review of its expression, function, and inhibitor development

Cancer is a major public health problem facing contemporary society. Notwithstanding considerable progress in medicine in recent decades, a cure for numerous cancer kinds continues to be unattainable. Thus, the pursuit of innovative therapeutic targets and methodologies remains paramount in medical research. The advancement of lipidomics has progressively revealed the essential roles of lipid metabolic pathways. Sphingosine kinase (SphK) and sphingosine-1-phosphate (S1P) are essential molecules in sphingolipid metabolism, significantly influencing physiological functions. Two isoforms of SphK exist including SphK1 and SphK2, both of which exhibit significant expression levels within a spectrum of cancers. The involvement of SphK1 in carcinogenesis has been thoroughly documented, whereas the significance of SphK2 in cancer remains inadequately elucidated. This review retrospectively and extensively elucidates the expression and distribution of SphK2 in cancer, its methods of action, and advancements in inhibitor research, emphasizing the varied functions of the SphK2 in oncogenesis. The objective is to furnish novel insights for study and therapeutic applications concerning SphK2 in oncology.

Actin-Targeted Magnetic Nanomotors Mechanically Modulate the Tumor Mechanical Microenvironment for Cancer Treatment

The abnormal mechanical microenvironment is a hallmark feature of solid tumors and plays a key role in immunotherapy resistance. The actin cytoskeleton can be finely tuned to control cell mechanics, which becomes a central target to regulate the tumor mechanical microenvironment (TMME). Here, we propose an actin-binding protein-modified magnetic nanomotor (ABP-MN) coupled with the rotating magnetic field (MF) to dynamically regulate the actin cytoskeleton for remodeling the TMME. ABP-MNs, with an ultrasmall diameter of 23 nm, intracellularly target the actin cytoskeleton and induce depolymerization via magneto-mechanical force under MF. Cancer-associated fibroblasts (CAFs) and tumor cells, which internalize ∼69.3% of ABP-MNs, are significantly tuned under MF with signs of a 7-fold decrease in tumor matrix stiffness, increased immune cell infiltration, and 95.8% tumor growth inhibition. This strategy unlocks a fresh field to reshape the TMME with the intracellular mechanical approach, thereby providing an effective mechano-based therapy in treating solid tumors.

Carbon nanoparticles-Fe(II) complex combined with sorafenib for ferroptosis-induced antitumor effects in triple-negative breast cancer

Triple negative breast cancer (TNBC) represents an aggressive subtype of breast cancer that lacks the expression of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2, whose systemic treatment options are currently limited to chemotherapy. Carbon nanoparticles-Fe(II) complex (CNSI-Fe) is a promising antitumor drug that induces ferroptosis to kill tumor cells efficiently. In this study, we combined CNSI-Fe and a ferroptosis inducer sorafenib (SRF) to achieve the efficient chemotherapy of TNBC. CNSI-Fe could adsorb SRF by hydrophobic interaction and π-π stacking with a maximum adsorption capacity of 31 mg/g. During the in vitro assays, CNSI-Fe+SRF combination inhibited the cell viability of 4T1 cells much more efficiently than CNSI-Fe or SRF alone. The high Fe uptake, hydroxyl radical generation and oxidative damages verified the ferroptosis of 4T1 cells upon the CNSI-Fe+SRF treatment. During the in vivo evaluations, SRF enhanced the therapeutic effect of CNSI-Fe as indicated by the higher tumor growth inhibition rate of 67.8 % and the higher survival rate. CNSI captured SRF in tumor to give a 6 mg/kg uptake, which lowered the glutathione peroxidase 4 (GPX4) level and enhanced the hydroxyl radical production of 4T1 tumor. In addition, CNSI-Fe treatment up-regulated the genes associated with antioxidative responses, but the up-regulation was offset by SRF. CNSI-Fe+SRF group showed similar toxicity to mice as SRF alone in the biosafety evaluations. Our results collectively indicated that the combination of CNSI-Fe and SRF could efficiently treat TNBC through ferroptosis.

SMYD4 promotes MYH9 ubiquitination through lysine monomethylation modification to inhibit breast cancer progression

BACKGROUND

Breast cancer is the leading cause of female mortality worldwide. (SET And MYND Domain Containing 4) SMYD4 has been reported to be a tumour suppressor. However, the molecular mechanism of SMYD4 remains unclear.

METHODS

The expression level of SMYD4 in breast cancer cells was detected by qRT-PCR and western blot. The effect of SMYD4 was verified in vitro and in vivo. The interaction between SMYD4 and MYH9 was investigated by co‑IP assay. The regulation of SMYD4 on WNT signaling pathway was detected by luciferase reporter assay and ChIP analysis.

RESULTS

This study found that SMYD4 downregulation was associated with poor prognosis. SMYD4 was performed as a tumor suppressor both in vitro and in vivo. SMYD4 was found to interact with the downstream protein MYH9 and impede WNT signaling pathway. Further studies revealed that SMYD4 impeded the binding of MYH9 to the CTNNB1 promoter region by promoting lysine monomethylation and ubiquitination degradation of MYH9.

CONCLUSIONS

These findings reveal the emerging character of SMYD4 in Wnt/β‑catenin signaling and bring new sights of gene interaction. The discovery of this SMYD4/MYH9/CTNNB1/WNT/β-Catenin signalling pathway axis suggests that SMYD4 is a potential therapeutic target for breast cancer.

Core-shell vector-mediated co-delivery of CRISPR/Cas9 system and hydrophobic drugs against triple-negative breast cancer stem cells

Cancer stem cells (CSCs) play an important role in the development of triple-negative breast cancer (TNBC), including metastasis, invasion, tumorigenicity, and drug resistance. Moreover, non-CSCs can spontaneously transform into CSCs in special tumor microenvironments, thereby leading to poor prognosis or even failed treatments. Therefore, reversing CSCs into normal tumor cells in a sustained-acting manner is a promising strategy. It has been reported that down-regulation of FBXO44 protein expression inhibits tumor cell stemness. Moreover, CRISPR/Cas9 technology, a well-known precise gene editing tool, was adopted to permanently block FBXO44 within the genome upon its successful implementation. Given this, a core-shell nanoparticle (NP) consisting of amphiphilic polymer core and crosslinked-hyaluronic acid shell (nDOX-PL/pFBXO44 NPs) is developed in this work to concurrently deliver FBXO44-targeted CRISPR/Cas9 plasmids (pFBXO44) and doxorubicin (DOX) for combinational CSC reprogramming and chemotherapy of TNBC, which exhibits tumor cell targeting, endosomal escape, and reduction responsiveness to release DOX and plasmids in the cytoplasma. CRISPR/Cas9-mediated downregulation of FBXO44 expression could convert CSC into normal tumor cells, and effectively inhibit tumor growth without obvious side effects in vivo after combining with chemotherapy. In summary, we developed an intelligent system to co-deliver genetic and hydrophobic drugs, achieving effective cancer stemness reversal and synergistic suppression of contractable TNBC.

Clinical Relevance of Immunohistochemical Subtypes in Early-Stage, Lymph Node-negative Breast Cancer. Results of a Large Cohort Study

AIMS

This study aimed to provide the association of immunohistochemical (IHC) subtypes of early-stage, lymph node-negative breast cancer with clinical outcomes. The relevance of adjuvant systemic therapy (AST) with respect to triple-negative cancers was given special attention.

MATERIALS AND METHODS

We used the data of 1,959 breast-conserving therapies (BCTs) in 1,861 women diagnosed with early-stage unilateral, lymph node-negative breast cancer treated between 2004 and 2015.

RESULTS

Overall, IHC subtypes were not associated with disease-specific survival (DSS) or overall survival (OS) in multivariate analyses. Looking at the influence of AST, administered according to current guidelines, we noted that triple-negativity compared to luminal A demonstrated a better DSS (hazard ratio [HR]: 0.4, 95% confidence interval [CI]: 0.1-1.1). For those without AST, outcomes for all subtypes did not differ. Difference in outcome of triple-negative tumours for without and with AST was mainly due the presence of patients bearing histological grade 3 cancers in those without AST.

CONCLUSION

In early-stage, lymph node-negative breast cancer treated with BCT and AST, according to existing guidelines, triple-negativity demonstrated a better outcome in DSS. However, for those without AST, no differences were seen in outcome between the various subtypes.

Pharmacological activity of OST-01, a natural product from baccharis coridifolia, on breast cancer cells

Natural products have long been a viable source of therapeutic agents, providing unique structures and mechanisms that may be beneficial for cancer treatment. Herein we first report on the anticancer activity OST-01, a natural product from Baccharis Coridifolia, on breast cancer cells, including triple-negative breast cancer (TNBC). OST-01 significantly inhibited cell proliferation and oncogenic activities of TNBC cells in vitro. OST-01 also markedly inhibited TNBC tumor growth in vivo, with > 50% reduction in tumor size compared to vehicle control treatment in different in vivo models, i.e., cell line-derived (CDX), patient-derived (PDX), and mammary fat pad xenografts. Mechanistically, OST-01 induces ferroptosis by downregulating LRP8-regulated selenoproteins, i.e., GPX4. A shift from a basal-mesenchymal to a luminal-epithelial state of breast cancer stem cells (BCSCs) as supported by the downregulation of stemness (e.g., CD44) and mesenchymal (e.g., FN1 and vimentin) markers, along with the upregulation of differentiation markers (e.g., CD24) and luminal-epithelial markers (e.g., CK19), was also observed.

Molecular structure of polysaccharide mediated autophagy markers KIF23 and PRC1 proteins and their regulatory role in triple negative cancer through the p53 signaling pathway

As a process of intracellular degradation and recycling of its own components, abnormal regulation of autophagy has been strongly associated with the development of multiple cancer types, including triple-negative breast cancer. The amino acid sequences of KIF23 and PRC1 proteins were analyzed by bioinformatics method, their three-dimensional structures were predicted, and their interactions with polysaccharides were studied by molecular docking technology. The localization and expression patterns of KIF23 and PRC1 in cells were studied by cell biology techniques. By constructing breast cancer cell lines that stably overexpress or knock down KIF23 and PRC1, we evaluated the effect of these proteins on autophagy activity. Finally, molecular biological methods such as Western blot and real-time quantitative PCR were used to detect the expression changes of proteins related to p53 signaling pathway and the levels of autophagy markers such as LC3 and p62, thereby revealing the regulatory effects of KIF23 and PRC1 on autophagy of triple-negative breast cancer cells through p53 signaling pathway. The study found that the KIF23 and PRC1 proteins have complex three-dimensional structures, and their interactions with polysaccharides may affect their function during cell division and autophagy. In triple-negative breast cancer cells, overexpression of KIF23 and PRC1 significantly enhanced autophagy activity, while knockdown of these proteins inhibited autophagy. Further experiments showed that KIF23 and PRC1 regulate the expression of autophagy related proteins by influencing the activity of p53 signaling pathway. Overexpression of KIF23 and PRC1 led to inhibition of the p53 signaling pathway, while knocking down these proteins activated the p53 signaling pathway, which was consistent with reduced autophagy activity.

Correlation Between Disease-Free Survival Endpoints and Overall Survival in Elderly Patients with Early-Stage HER2-Negative Breast Cancer: A SEER-Medicare Analysis

INTRODUCTION

Recent trial-level meta-analyses have established disease-free survival (DFS) as a valid surrogate for overall survival (OS) in human epidermal growth factor receptor 2-negative (HER2-) breast cancer (BC), irrespective of disease stage, and in early-stage hormone receptor-positive (HR+)/HER2- BC. To advance the understanding of the association between additional DFS endpoints and OS, this study assessed the patient-level correlations between DFS and OS, invasive DFS (IDFS) and OS, and distant DFS (DDFS) and OS in Medicare beneficiaries with early-stage HER2- BC, overall and in subgroups of patients with HR+/HER2- BC and triple-negative BC (TNBC).

METHODS

Patients with stages I-III HER2- BC aged ≥ 66 years were identified from SEER-Medicare data (2010-2019). DFS, IDFS, DDFS, and OS were assessed using Kaplan-Meier analyses. Normal scores rank correlation was estimated between each DFS endpoint and OS, overall and separately in patients with HR+/HER2- BC and TNBC.

RESULTS

Of 28,655 patients, 90.4% had HR+/HER2- BC and 9.6% had TNBC (median follow-up 4 years). Median DFS, IDFS, and DDFS were 4.5, 5.9, and 6.3 years, respectively, in HR+/HER2- BC and 3.0, 3.8, and 4.4 years, respectively, in TNBC. Median OS was not reached (5-year OS, HR+/HER2- BC 83.7%; TNBC 67.7%). A significant positive correlation was observed between each DFS endpoint and OS across cohorts, with the strongest correlation observed between DDFS and OS in HR+/HER2- BC (correlation coefficient 0.60; 95% confidence interval 0.57-0.62; p < 0.001) and in TNBC (0.69; 0.65-0.71; p < 0.001).

CONCLUSION

We observed significant positive patient-level correlations between DFS and OS, IDFS and OS, and DDFS and OS in early-stage HER2- BC. Our IDFS and DDFS findings advance the understanding of the role of these DFS endpoints as predictors of OS, and their potential utility as surrogate endpoints in clinical trials of early-stage HER2- BC, given additional validation in trial-level meta-analyses.

TROP2 regulates cisplatin sensitivity of triple-negative breast cancer cells by regulating endoplasmic reticulum stress

Triple-negative breast cancer (TNBC) is a kind of breast cancer with a high metastasis rate and poor prognosis. As a transmembrane glycoprotein, tumor-associated calcium signal transducer 2 (TROP2) plays a certain role in the cancers. This study aimed to explore the potential mechanism of TROP2 affecting cisplatin (CDDP) resistance in TNBC from endoplasmic reticulum stress (ERS). MDA-MB-231 and CDDP-resistant cell lines MDA-MB-231/CDDP were used in this study, and the expression of TROP2 was detected by western blotting. After transfecting with the interference sequence of siRNA targeting TROP2, cell proliferation and apoptosis were detected by the cell counting kit-8, colony formation, and flow cytometry, and the expression of ERS-marker proteins was detected by western blotting. Furthermore, the effects of ERS in TROP2 on drug resistance of TNBC cells were explored by using ERS inhibitor 4-phenylbutyric acid (4-PBA). Results found that TROP2 expression in MDA-MB-231/CDDP was significantly upregulated compared with MDA-MB-231. The expression of TROP2 in MDA-MB-231/CDDP was significantly decreased after transfection with siRNA-TROP2, and the proliferation of MDA-MB-231 and MDA-MB-231/CDDP cells was significantly decreased after further induction with CDDP. TROP2 significantly affected TNBC cell cloning, apoptosis, and the expression of ERS-related marker proteins, while 4-PBA reversed the promoting effects of siRNA-TROP2 on apoptosis and ERS, as well as the inhibitory effects on cell proliferation, suggesting that TROP2 affected the resistance of TNBC cells to CDDP through ERS. In conclusion, TROP2 inhibited apoptosis of TNBC cells, improved the cell cloning ability, and regulated the sensitivity of TNBC cells to CDDP through ERS.

Concurrent Amplification of Ferroptosis and Immune System Activation Via Nanomedicine-Mediated Radiosensitization for Triple-Negative Breast Cancer Therapy

Radiation therapy (RT) is one of the core therapies for current cancer management. However, the emergence of radioresistance has become a major cause of radiotherapy failure and disease progression. Therefore, overcoming radioresistance to achieve highly effective treatment for refractory tumors is significant yet challenging. Here, pH-responsive DSPE-PEoz modified hollow Bi2Se3-RSL3/diABZi (DP-HBN/RA) nanomedicine is designed as a radiation sensitizer for efficient treatment of triple-negative breast cancer by simultaneously amplifying ferroptosis and immune system activation. DP-HBN/RA can efficiently concentrate X-ray radiation energy inside the tumor, thereby promoting precise ionizing radiation exposure in tumor cells to produce large amounts of reactive oxygen species (ROS), leading to lipid peroxidation-induced ferroptosis. Meanwhile, ferroptotic cell death is intensified through the inactivation of GPX4 by RSL3 released from DP-HBN/RA to acidic conditions in the tumor microenvironment. Additionally, DP-HBN/RA enhances RT efficacy to exacerbate unrepairable DNA damage and release DNA fragments that activate the cGAS-STING signal pathway, evoking a systematic immune response. Ingeniously, the released diABZi reinforces cGAS-STING activation to boost the immunology antitumor effect. This work links the induction of ferroptosis and the initiation of systematic immune response to achieve highly effective tumor suppression, which opens up new avenues for future treatments of refractory tumors.

Protein lactylation within the nucleus independently predicts the prognosis of non‑specific triple‑negative breast cancer

Protein lactylation represents a pervasive post-translational modification prevalent in histones and diverse proteins, fostering tumor initiation and progression. Nonetheless, the impact of protein lactylation on the prognosis of non-specific triple-negative breast cancer (TNBC) remains uncertain. In the present study, the pan-lysine lactylation (panKlac) levels in cytoplasmic and nuclear compartments were semi-quantitatively examined using a tissue microarray encompassing 77 non-specific TNBC tissues. The association of the prognosis of patients with the panKlac levels in the cytoplasmic and nuclear compartments or other tumor attributes was assessed using Kaplan-Meier and Cox regression analyses. Furthermore, the molecular pathways involved in the promotional effect of lactylation on cell proliferation were determined through a transcriptomic analysis. The results indicated that the panKlac levels were markedly higher in tumor tissues than in para-tumor mammary regions and showed no significant correlations with various clinicopathological parameters, such as tumor dimension, lymph node involvement or histological grading. Notably, high panKlac levels within the nucleus served as an independent predictor of recurrence-free survival, whereas high cytoplasmic panKlac levels were a protective factor for patient survival. The panKlac levels were also markedly elevated in the TNBC cell line, MDA-MB-231. Additionally, glycolysis inhibition significantly reduced the global panKlac levels and concurrently diminished cell proliferation. According to the comprehensive transcriptomic analysis results, pathways related to ribosomal subunit biosynthesis/assembly and aminoacyl-tRNA biosynthesis were involved in the tumor-promoting mechanisms of lactylation. Further results revealed the oncogenic propensity of tyrosyl-tRNA synthetase 1 (YARS1) and its association with lactate production. Overall, Klac levels within the nucleus are an independent prognostic indicator for patients with non-specific TNBC. It is imperative to delve deeper into the roles and mechanisms of nuclear protein lactylation and YARS1 in non-specific TNBC.

Functionalized biomimetic nanoparticles loaded with salvianolic acid B for synergistic targeted triple-negative breast cancer treatment

The therapeutic effect of immune checkpoint inhibitors (ICIs) in triple-negative breast cancer (TNBC) is unsatisfactory. The immune "cold" microenvironment caused by tumor-associated fibroblasts (TAFs) has an adverse effect on the antitumor response. Therefore, in this study, mixed cell membrane-coated porous magnetic nanoparticles (PMNPs) were constructed to deliver salvianolic acid B (SAB) to induce an antitumor immune response, facilitating the transition from a "cold" to a "hot" tumor and ultimately enhancing the therapeutic efficacy of immune checkpoint inhibitors. PMNP-SAB, which is based on a mixed coating of red blood cell membrane and TAF membrane (named PMNP-SAB@RTM), can simultaneously achieve the dual effects of "immune escape" and "homologous targeting". Under the influence of an external magnetic field (MF), SAB can be targeted and concentrated at the tumor site. The SAB released in tumors can effectively inhibit the production of extracellular matrix (ECM) by TAFs, promote T-cell infiltration, and induce antitumor immune responses. Ultimately, the combination of PMNP-SAB@RTM and BMS-1 (PD-1/PD-L1 inhibitor 1) effectively inhibited tumor growth. Finally, this study presents a precise and effective new strategy for TNBC immunotherapy on the basis of the differentiation of "cold" and "hot" microenvironments.

Anticancer potential of osthole: targeting gynecological tumors and breast cancer

Gynecological tumors, such as ovarian, endometrial, and cervical cancers, alongside breast cancer, represent significant malignancies that pose serious threats to women's health worldwide. Standard treatments, including surgery, chemotherapy, radiotherapy, and targeted therapies, are commonly utilized in clinical practice. However, challenges such as high recurrence rates, drug resistance, and adverse side effects underscore the urgent need for more effective therapeutic options. Osthole, a natural coumarin compound derived from Chinese herbal medicine, has demonstrated remarkable antitumor activity against various cancers. Emerging evidence indicates that osthole can inhibit the proliferation, invasion, and metastasis of gynecological and breast cancer cells through various mechanisms, including inducing apoptosis and autophagy, regulating the tumor microenvironment, inhibiting tumor angiogenesis, and enhancing the sensitivity of cancer cells to chemotherapy and radiotherapy. This review highlights the recent advancements in osthole research within the context of gynecological and breast cancers, focusing on its molecular mechanisms, and offers a theoretical foundation for its potential development as an anticancer agent.

Nanoparticles Modulating the Immune Microenvironment in Breast Cancer Treatment

Breast cancer remains a significant therapeutic challenge, with the immune microenvironment playing a crucial role in its progression and treatment response. This review investigates the potential of nanoparticles to modulate the immune microenvironment in breast cancer therapy. Initially, we discuss the composition and influence of the immune microenvironment on breast cancer, followed by current strategies targeting these components. We then provide strategies of nanoparticles for targeting immune cells such as macrophages, dendritic cells, and T-cells. The role of nanoparticles in enhancing immune checkpoint blockade (ICB) and their application in cancer vaccines is also examined. Additionally, we explore the synergistic effects of combining nanoparticles with conventional therapies. The review addresses the challenges in clinical translation, focusing on safety, biocompatibility, and toxicity. Finally, we outline future research directions and the potential advancements in nanoparticle-based immunotherapy, emphasizing their transformative impact on breast cancer treatment.

Tumor Microenvironment-Responsive Nanoparticles Enhance IDO1 Blockade Immunotherapy by Remodeling Metabolic Immunosuppression

The clinical efficacy of immune checkpoint blockade (ICB) therapy is significantly compromised in the metabolically disordered tumor microenvironment (TME), posing a formidable challenge that cannot be ignored in current antitumor strategies. In this study, TME-responsive nanoparticles (HMP1G NPs) loaded with 1-methyltryptophan (1-MT; an indoleamine 2,3-dioxygenase 1 [IDO1] inhibitor,) and S-nitrosoglutathione (GSNO; a nitric oxide donor) is developed to enhance the therapeutic efficacy of 1-MT-mediated ICB. The HMP1G NPs responded to H+ and glutathione in the TME, releasing Mn2+, GSNO, and 1-MT. The released Mn2+ catalyzed the production of abundant reactive oxygen species and nitric oxide from hydrogen peroxide and GSNO, and the generated nitric oxide, synergistically with 1-MT, inhibited the accumulation of kynurenine mediated by IDO1 in the tumor. Mechanistically, HMP1G NPs downregulated tumor cell-derived IDO1 via the aryl hydrocarbon receptor/signal transducer and activator of transcription 3/interleukin signaling axis to improve kynurenine/tryptophan metabolism and immunosuppression. In a murine breast cancer model, treatment with HMP1G NPs elicited effective antitumor immunity and enhanced survival outcomes. This study highlights a novel nano-platform that simultaneously improves metabolism and enhances ICB efficacy to achieve a new and efficient antitumor strategy.

Gadolinium ion-loaded mesoporous organosilica nanoplatform for enhanced radiotherapy in breast tumor treatment

Triple-negative breast cancer (TNBC) is a highly aggressive subtype with limited therapeutic options, often exhibiting resistance to standard radiotherapy (RT) and chemotherapy. Recent advancements in nanomedicine provide an opportunity to enhance treatment efficacy through innovative drug delivery systems and radiosensitizers. In this study, we present a novel nanotheranostic platform, MOs-G@DOX, engineered to enhance the therapeutic efficacy of RT in the treatment of TNBC. This platform consists of gadolinium-containing mesoporous organosilica nanoparticles (MOs-G) that serve a dual function as a drug carrier and a radiosensitizer. The MOs-G were synthesized via a surfactant-mediated sol-gel process, followed by gadolinium incorporation through nanoprecipitation. The antitumor drug doxorubicin (DOX) was subsequently loaded into the mesoporous structure, forming the MOs-G@DOX nanoplatform. Comprehensive in vitro and in vivo studies demonstrated that MOs-G@DOX exhibits excellent biocompatibility and significantly enhances the radiosensitivity of TNBC cells, leading to superior tumor growth inhibition compared to conventional treatments. The stability of MOs-G, with minimal gadolinium ion leakage, further underscores its potential as a safe and effective nanomedicine. Additionally, the combination of MOs-G@DOX with RT showed a marked increase in reactive oxygen species (ROS) generation and tumor cell apoptosis, which were confirmed through histological analyses. These findings suggest that MOs-G@DOX is a promising candidate for advancing cancer therapy, particularly in the context of RT for TNBC.

Recent advances targeting chemokines for breast cancer

Breast cancer (BC) is a complex and heterogeneous disease, and its onset and progression involve the interplay of multiple molecular mechanisms. Chemokines and their receptors are key regulators of cell migration and immune responses and contribute significantly to the pathophysiology of BC. This article reviews the classification, functions, and mechanisms of chemokines and their receptors in the proliferation, migration, invasion, and angiogenesis of BC cells. This study explores the regulatory roles of chemokines and their receptors in the immune microenvironment of BC, particularly the ways they influence the infiltration, polarization, and antitumor immune responses of immune cells. Finally, this article summarizes the current treatment strategies for breast cancer that utilize chemokines and their receptors and provides insights into future research directions and trends in this field.

Expression and prognostic impact of hypoxia- and immune escape-related genes in triple-negative breast cancer: A comprehensive analysis

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that lacks effective therapeutic options. Hypoxia and immune escape are critical factors that contribute to the progression of and resistance to therapy in patients with TNBC. Nevertheless, few studies have comprehensively analyzed hypoxia and immune escape in patients with TNBC. This study aimed to examine the expression of hypoxia- and immune escape-related genes in TNBC and their influence on prognosis. TNBC datasets were downloaded and processed from The Cancer Genome Atlas and Gene Expression Omnibus. Differential expression analysis identified 4949 differentially expressed genes, between TNBC and normal tissues. The intersection yielded 116 hypoxia- and immune escape-related differentially expressed genes (H&IERDEGs), including KIF4A, BIRC5, and BUB1. Enrichment analyses indicated that H&IERDEGs were significantly enriched in biological processes, including cell chemotaxis, leukocyte migration, and cytokine-cytokine receptor interaction. Subsequently, weighted gene co-expression network analysis identified 43 module genes that were found to define two TNBC subtypes. We constructed a prognostic risk model consisting of eight signature genes, which demonstrated a high predictive performance to predict the overall survival (OS) of patients with TNBC with an area under the curve (AUC) exceeding 0.9 at 1 year survival. This indicates that the model effectively differentiates between outcomes, reflecting its robust performance. This study investigated the roles and potential mechanisms of hypoxia- and immune escape-related genes in TNBC and constructed a prognostic risk model with a high predictive performance. These findings offer novel molecular markers and potential therapeutic targets for TNBC.

Intrinsic subtype and immunity score in identification of triple-negative breast cancer at low risk

INTRODUCTION

Triple-negative breast cancer (TNBC) is group of heterogeneity caner. Despite majority of them had the unfavorable prognosis, a subset of patients who do not receive chemotherapy exhibit a good prognosis. Biomarkers are required to recognize these group of pateints and improve the current therapeutic strategies for them.

METHODS

A retrospective analysis of 997 patients with TNBC from three datasets including 188 case of Peking Union Medical College Hospital (PUMCH) and two TNBC datasets from published cohort studies(279 case of Affy-set, 530 case of GSE set) was conducted. Intrinsic subtypes (basal-like, immune-enhanced, human epidermal growth factor receptor-2 [HER2]-enriched and luminal A/B) and tumor environmental immunity were evaluated using expression profiles of a 72-gene panel. Association of intrinsic subtype and immunity score with distant metastasis-free survival (DMFS) and overall survival (OS) was analyzed.

RESULTS

Five intrinsic subtypes were identified in the patients with TNBC, comprising 64 % basal-like, 19 % immune-enhanced, 11 % HER2-enriched, 5 % luminal A, and 2 % luminal B. In the absence of adjuvant chemotherapy (ACT), Luminal A and immune-enhanced subtypes showed better DMFS than basal-like, HER2-enriched, and luminal B subtypes(P = 0.35). Significantly good OS was observed in luminal A and immune-enhanced subtypes compared to basal-like and HER2-enriched subtypes (P < 0.05). So two subtype groups were further classified as low-risk subtypes, including luminal A and immune-enhanced, and high-risk subtypes, including basal-like, HER2-enriched, and luminal B. Except for the immune-enhanced subtype, each subtype was further sorted and grouped according to immunity score, istrong and iweak. Significant improvements in both DMFS and OS were observed in patients with istrong compared with those with iweak(P = 0.01 and 0.0051 respectively). When combining intrinsic subtype and immunity status to predict the benefit from ACT, all high-risk subtype patients demonstrated improved DMFS(P = 0.075) and OS(P < 0.0001), with istrong patients exhibiting greater benefit; low-risk subtype plus iweak patients showed marginal benefit, whereas low-risk subtype plus istrong patients demonstrated least benefit from ACT.

CONCLUSION

Intrinsic subtype and immunity score is good prognostic biomarkers for patients with TNBC in the absence of chemotherapy. Combined intrinsic subtype and immunity evaluation could identify patients with TNBC who do not benefit from chemotherapy.

Mechanistic insights into pachymic acid's action on triple-negative breast Cancer through TOP2A targeting

Triple-negative breast cancer (TNBC) is characterized by the absence of estrogen and progesterone receptors, and lack of human epidermal growth factor receptor 2 (HER2) expression. Traditional Chinese medicine (TCM) has demonstrated promising efficacy in treating TNBC. This study explored the mechanisms of pachymic acid (PA) on TNBC by merging network pharmacology with experimental validation. We acquired Microarray data of TNBC from the Gene Expression Omnibus (GEO). The related targets of PA were predicted and screened using the following 6 databases: Swiss Target Prediction, HERB (Herbal Medicine Database), ETCM (Encyclopedia of Traditional Chinese Medicine), BATMAN (Bioinformatics Analysis Tool for Molecular Mechanism of Traditional Chinese Medicine), HIT (Herb Ingredients' Targets Database), and PharmMapper. The STRING interaction network analysis tool was used to create Protein-Protein Interaction (PPI) networks. Enrichment analysis included Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). We conducted a pan-cancer analysis, tumor immune microenvironment analysis, and molecular docking. We performed cell experimental, included cytotoxicity assay, apoptosis analysis, proliferation assay, and migration and invasion assays. PA has potential for treating TNBC with the target of TOP2A, and platinum drug resistance possibly serving as the KEGG pathway through which PA exerts its therapeutic effects. PA is involved in processes such as nuclear division, chromosome segregation, mitotic nuclear division, condensed chromosome formation, and protein C-terminus binding. PA probably exert its therapeutic effects through the tumor immune microenvironment, involving elements such as Dendritic cells activated, Eosinophils, Macrophages M0, Macrophages M1, and T cells CD4 memory activated. The therapeutic effects of PA may vary across different subtypes of TNBC such as TNBC-BL1, TNBC-Metaplastic, and TNBC-BL2. This study provides compelling evidence that PA holds significant promise as a therapeutic agent for TNBC, primarily through its action on TOP2A and its influence on the TNBC.

Ultrasound-activated erythrocyte membrane-camouflaged Pt (II) layered double hydroxide enhances PD-1 inhibitor efficacy in triple-negative breast cancer through cGAS-STING pathway-mediated immunogenic cell death

Rationale: Immunogenic cell death (ICD) offers a promising avenue for the treatment of triple-negative breast cancer (TNBC). However, optimizing immune responses remains a formidable challenge. This study presents the design of RBCm@Pt-CoNi layered double hydroxide (RmPLH), an innovative sonosensitizer for sonodynamic therapy (SDT), aimed at enhancing the efficacy of programmed cell death protein 1 (PD-1) inhibitors by inducing robust ICD responses. Methods: Pt-CoNi layered double hydroxide (LDH) nanocages were synthesized using a two-step method, followed by functionalization with red blood cell membranes to prepare RmPLH. The in vitro assessments included evaluations of cell toxicity, cellular uptake, and sonodynamic effects of RmPLH. Key mechanisms-such as oxidative stress, DNA damage, pyroptosis, cGAS/STING pathway activation, and inhibition of cellular migration and invasion-were explored under varying treatment conditions in 4T1 cells. Tumor-bearing mice were employed to evaluate tumor-targeting capabilities and the synergistic tumor-suppressive effects of RmPLH combined with PD-1 inhibitors. Comprehensive safety evaluations, including blood tests, biochemical analyses, and histopathological examinations, were also conducted. Results: The synthesized Pt-CoNi LDH exhibited a uniform rhombic dodecahedral nanocage morphology with an average particle size of approximately 231 nm. Encapsulation with red blood cell membranes conferred prolonged systemic circulation, enhanced tumor targeting, and reduced immune clearance for RmPLH. Upon ultrasound (US) stimulation, the LDH released substantial levels of reactive oxygen species (ROS) and platinum ions. The ROS effectively induced endoplasmic reticulum stress and ferroptosis, while platinum ions facilitated DNA crosslinking, triggering significant DNA damage. ROS-induced pyroptosis released inflammatory mediators and damage-associated molecular patterns (DAMPs), which activated the cGAS/STING pathway and reinforced ICD. Combining RmPLH with PD-1 inhibitors significantly enhanced therapeutic efficacy against TNBC. Furthermore, safety assessments confirmed the excellent biocompatibility and biosafety of RmPLH. Conclusion: The integration of RmPLH with PD-1 inhibitors substantially amplifies ICD, fostering robust antigen-specific T cell immunity and offering a promising therapeutic strategy for TNBC. This study represents a pioneering application of Pt (II)-based LDH nanocages in oncology, laying a foundation for future innovations in tumor immunotherapy.

FOSL1 transcriptionally dictates the Warburg effect and enhances chemoresistance in triple-negative breast cancer

BACKGROUND

Dysregulated energy metabolism has emerged as a defining hallmark of cancer, particularly evident in triple-negative breast cancer (TNBC). Distinct from other breast cancer subtypes, TNBC exhibits heightened glycolysis and aggressiveness. However, the transcriptional mechanisms of aerobic glycolysis in TNBC remains poorly understood.

METHODS

The Cancer Genome Atlas (TCGA) cohort was utilized to identify genes associated with glycolysis. The role of FOSL1 in glycolysis and tumor growth in TNBC cells was confirmed through both loss-of-function and gain-of-function experiments. The subcutaneous xenograft model was established to evaluate the therapeutic potential of targeting FOSL1 in TNBC. Additionally, chromatin immunoprecipitation and luciferase reporter assays were employed to investigate the transcriptional regulation of glycolytic genes mediated by FOSL1.

RESULTS

FOSL1 is identified as a pivotal glycolysis-related transcription factor in TNBC. Functional verification shows that FOSL1 enhances the glycolytic metabolism of TNBC cells, as evidenced by glucose uptake, lactate production, and extracellular acidification rates. Notably, FOSL1 promotes tumor growth in TNBC in a glycolysis-dependent manner, as inhibiting glycolysis with 2-Deoxy-D-glucose markedly diminishes the oncogenic effects of FOSL1 in TNBC. Mechanistically, FOSL1 transcriptionally activates the expression of genes such as SLC2A1, ENO1, and LDHA, which further accelerate the glycolytic flux. Moreover, FOSL1 is highly expressed in doxorubicin (DOX)-resistant TNBC cells and clinical samples from cases of progressive disease following neoadjuvant chemotherapy. Targeting FOSL1 proves effective in overcoming chemoresistance in DOX-resistant MDA-MB-231 cells.

CONCLUSION

In summary, FOSL1 establishes a robust link between aerobic glycolysis and carcinogenesis, positioning it as a promising therapeutic target, especially in the context of TNBC chemotherapy.

PD‑1/PD‑L1 inhibitor‑based immunotherapy in locally advanced or metastatic triple‑negative breast cancer: A meta‑analysis

Triple-negative breast cancer (TNBC) is a subtype of breast cancer that is negative for oestrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 expression. Locally advanced and metastatic TNBC not only have a worse prognosis and are more invasive than TNBC, but are also the most immunogenic subtypes of breast cancer. There is still a lack of clarity regarding the optimal treatment of locally advanced or metastatic TNBC. The present study aimed to assess the efficacy and safety of programmed cell death protein 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitor-based immunotherapy [i.e., immune checkpoint inhibitors (ICIs)] alone or in combination with other therapies for the treatment of locally advanced or metastatic TNBC. The PubMed, Cochrane Library, Embase and MEDLINE databases were searched up to July 19, 2023 to identify studies that examined the efficacy and safety of ICIs for treating TNBC. The primary outcomes were progression-free survival (PFS) and overall survival (OS). The secondary outcomes were safety and adverse events. The data were analysed using Review Manager 5.4. A total of 8 studies (3,338 patients) were included in the present meta-analysis. Compared with other therapies, ICIs had a significantly different effect on OS [hazard ratio (HR)=0.83; 95% confidence interval (CI)=0.69-1.00; P<0.05; I2=59%] in patients with locally advanced or metastatic TNBC. In addition, ICIs significantly prolonged PFS compared with other therapies (intent-to-treat: HR=0.81; 95% CI=0.75-0.88; P<0.00001; I2=0%). Immunotherapy based on PD-1/PD-L1 inhibitors showed variable efficacy on OS and PFS in TNBC, while a significant improvement was observed for PD-L1(+). Future studies should focus on PD-L1 subgroup status, which may help optimize personalized treatment regimens for TNBC.

Carbonic Anhydrase IX Enzyme in Triple Negative Breast Carcinoma: Relationship With Prognostic Factors and Response to Neoadjuvant Chemotherapy

Objective

Triple negative breast carcinoma (TNBC) is characterized by the absence of estrogen receptor, progesterone receptor and human epidermal growth factor receptor-2 receptor expression. Carbonic anhydrase IX (CA IX) is a tumor-associated cell surface glycoprotein that is involved in adaptation to hypoxia-induced acidosis and plays a role in cancer progression. The aim of this study was to investigate CA IX expression in TNBC and its relationship with treatment effect.

Materials and Methods

Immunohistochemical staining was performed on tru-cut biopsy materials with CA IX antibody. Positive staining was graded as low (<10%) and high (>10%). In addition, the relationship between tumor diameter, histological grade and the treatment effect on mastectomy materials performed after neoadjuvant treatment was evaluated.

Results

TNBCs with positive staining for CA IX exhibited higher histological grade, and higher Ki-67 index compared to TNBCs with negative staining (p < 0.05). The response to treatment decreased as the degree of CA IX staining increased. There was no significant difference between the high staining group and low staining group in terms of patient age, tumor diameter and breast localisation.

Conclusion

CA IX enzyme is a poor prognostic marker in TNBC cases. However, overexpression of CA IX was associated with reduced response to treatment.

Molecular Basis of Breast Tumor Heterogeneity

Breast cancer (BC) is a profoundly heterogenous disease, with diverse molecular, histological, and clinical variations. The intricate molecular landscape of BC is evident even at early stages, illustrated by the complexity of the evolution from precursor lesions to invasive carcinoma. The key for therapeutic decision-making is the dynamic assessment of BC receptor status and clinical subtyping. Hereditary BC adds an additional layer of complexity to the disease, given that different cancer susceptibility genes contribute to distinct phenotypes and genomic features. Furthermore, the various BC subtypes display distinct metabolic demands and immune microenvironments. Finally, genotypic-phenotypic correlations in special histologic subtypes of BC inform diagnostic and therapeutic approaches, highlighting the significance of thoroughly comprehending BC heterogeneity.

LncRNA MCM3AP-AS1 promotes chemoresistance in triple-negative breast cancer through the miR-524-5p/RBM39 axis

Triple-negative breast cancer (TNBC) is the most lethal subtype of BC, with unfavorable treatment outcomes. Evidence suggests the engagement of lncRNA MCM3AP-AS1 in BC development. This study investigated the action of MCM3AP-AS1 in chemoresistance of TNBC cells. Drug-resistant TNBC cell lines SUM159PTR and MDA-MB-231R were constructed by exposure to increasing concentrations of doxorubicin/docetaxel (DOX/DXL). MCM3AP-AS1 and miR-524-5p expression levels were determined by RT-qPCR. RNA binding motif 39 (RBM39) level was measured using Western blot. Cell viability and apoptosis were assessed by CCK-8 assay and flow cytometry. The targeted binding of miR-524-5p with MCM3AP-AS1 or RBM39 was predicted by ECORI database and validated by dual-luciferase assays. The gain-and-loss of function assays were conducted in cells to investigate the interactions among MCM3AP-AS1, miR-524-5p, and RBM39. TNBC xenograft mouse models were established through subcutaneous injection of MCM3AP-AS1-silencing MDA-MB-231R cells and intraperitoneally administrated with DOX/DXL to verify the role of MCM3AP-AS1 in vivo. MCM3AP-AS1 was upregulated in drug-resistant TNBC cells, and MCM3AP-AS1 silencing could sensitize drug-resistant TNBC cells to chemotherapeutic drugs by promoting apoptosis. MCM3AP-AS1 targeted miR-524-5p. After DOX/DXL treatment, miR-524-5p inhibition partially reversed the effect of MCM3AP-AS1 silencing on inhibiting chemoresistance and promoting apoptosis of drug-resistant TNBC cells. miR-524-5p targeted RBM39. Silencing MCM3AP-AS1 promoted apoptosis via the miR-524-5p/RBM39 axis, thereby enhancing chemosensitivity of drug-resistant TNBC cells. MCM3AP-AS1 knockdown upregulated miR-524-5p, downregulated RBM39, and restrained tumor development in vivo. MCM3AP-AS1 silencing potentiates apoptosis of drug-resistant TNBC cells by upregulating miR-524-5p and downregulating RBM39, thereby suppressing chemoresistance in TNBC.

Uncovering novel pathogenic variants and pathway mutations in triple-negative breast cancer among the endogamous mizo tribe

PURPOSE

The incidence of triple-negative breast cancer (TNBC) in India is higher compared to Western populations. The objective of this study is to identify novel and less reported variants in TNBC in Mizoram, a state with a high cancer incidence in India.

METHODS

We analysed whole exome sequencing data from triple-negative breast cancer (TNBC) patients in the Mizo population to identify key and novel variants. Moreover, we analysed reported breast cancer-related genes and pathway alterations.

RESULTS

Somatic mutation analysis revealed that TP53 was the most frequently mutated gene and TP53, CACNA1E, IGSF3, RYR1, and FAM155A as significantly mutated driver genes. Based on the ACMG guidelines, we identified a rare pathogenic germline variant of BRCA1 (p.C1697R) in 13% and a likely pathogenic frameshift insertion in RBMX (p.P106Ffs) in 73% of the patients. We also found that the ATM, STK11, and CDKN2A genes were significantly mutated in germline TNBC samples compared to healthy samples. Moreover, we identified novel somatic variants in CHEK2 (p.K182M) and NF1 (p.C245X), and novel germline variants RB1 (p.D111G), CDH1 (p.A10Gfs), CDKN2A (p.V96G), CDKN2A (p.S12Afs*22), MAP3K1 (CAAdelins0), MSH6 (p.L1226_L1230del), and PMS2 (TTCdelins0). Pathway analysis revealed that most somatic mutations were highly associated with PI3K-Akt signalling pathway and MAPK signalling pathways in TNBC.

CONCLUSIONS

These findings identified novel variants and key genes contributing to disease development and progression. Further analysis of less studied genes, including RBMX, MRC1, ATM, CTNNB1, and CDKN2A, in TNBC may reveal new potential genes for targeted therapeutic strategies and contribute to clinical advancements in the treatment of TNBC.

FOS-Mediated PLCB1 Induces Radioresistance and Weakens the Antitumor Effects of CD8+ T Cells in Triple-Negative Breast Cancer

Radioresistance and immune evasion are interactive and crucial events leading to treatment failure and progression of human malignancies. This research studies the role of phospholipase C beta 1 (PLCB1) in these events in triple-negative breast cancer (TNBC) and the regulatory mechanism. PLCB1 was bioinformatically predicted as a dysregulated gene potentially linked to radioresistance in TNBC. Parental TNBC cell lines were exposed to fractionated radiation for 6 weeks. PLCB1 expression was decreased in the first 2 weeks but gradually increased from Week 3. PLCB1 knockdown increased the radiosensitivity of the cells, as manifested by a decreased half-inhibitory dose of irradiation, reduced cell proliferation, apoptosis resistance, mobility, and tumorigenesis in mice. The FOS transcription factor promoted PLCB1 transcription and activated the PI3K/AKT signaling. Knockdown of FOS similarly reduced radioresistance and T cells-mediated immune evasion. However, the radiosensitivity of TNBC cells and the antitumor effects of CD8+ T cells could be affected by a PI3K/AKT activator or by the PLCB1 upregulation. The PLCB1 or FOS knockdown also suppressed radioresistance and tumorigenesis of the TNBC cells in mice. In conclusion, FOS-mediated PLCB1 induces radioresistance and weakens the antitumor effects of CD8+ T cells in TNBC by activating the PI3K/AKT signaling pathway.

New Approach in the Interpretation of Complex Triple-negative Breast Cancer Immunohistochemistry Specimens Processed With VENTANA PD-L1 (SP142) Assay

Triple-negative breast cancer (TNBC) is challenging to treat because of its lack of specific molecular targets. The IMMUNOPEG study aimed to evaluate a novel structured method for interpreting TNBC immunohistochemistry specimens processed with VENTANA PD-L1 (SP142) assay. The study involved 10 pathologists who evaluated 50 different immunohistochemistry specimens of TNBC with programmed death ligand 1 (PD-L1) expression considered challenging and that were previously evaluated by the scientific committee, using the NAVIFY Digital Pathology platform. Initially, the overall percent agreement (OPA) was 74%, with a negative percent agreement (NPA) of 68.2% for samples classified as negative, and a positive percent agreement (PPA) of 94.5% for positive samples. After training on the method, the OPA improved significantly to 81.6%, with the NPA increasing to 80.5% and the PPA decreasing to 85.5%. The mean percentage of the tumor area occupied by PD-L1-stained immune cells decreased from 2.5% to 1.6% post-training, approaching to the scientific committee's consensus of 1.029%. The study found that the pathologists' confidence in their assessments increased significantly when using the structured method, which was found to be easy to use by 9 out of 10 pathologists. All pathologists agreed that the structured method was useful for assessing PD-L1 expression. The study suggests that this method has potential value in interpreting challenging cases of PD-L1 immunohistochemistry (IHC) in TNBC. Further refinement and a training protocol may be necessary to enhance the method's efficiency. The potential for generalizing this structured method to other IHC procedures and pathologies warrants additional research.

Canine mammary tumors as a promising adjunct preclinical model for human breast cancer research: similarities, opportunities, and challenges

Despite significant progress in the field of human breast cancer research and treatment, there is a consistent increase in the incidence rate of 0.5 percent annually, posing challenges in the development of effective novel therapeutic strategies. The failure rate of drugs in clinical trials stands at approximately 95%, primarily attributed to the limitations and lack of reliability of existing preclinical models, such as mice, which do not mimic human tumor biology. This article examines the potential utility of canine mammary tumors as an adjunct preclinical model for investigating human breast cancer. Given the numerous similarities between canine and human breast cancer, canines present a promising alternative model. The discussion delves into the intricate molecular and clinical aspects of human breast cancer and canine mammary tumors, shedding light on the tumors' molecular profiles, identifying specific molecular markers, and the application of radiological imaging modalities. Furthermore, the manuscript addresses the current constraints of preclinical cancer studies, the benefits of using canines as models, and the obstacles linked to the canine mammary tumors model. By concentrating on these elements, this review aims to highlight the viability of canine models in enhancing our understanding and management of human breast cancer.

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.

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.

circUBR5 promotes ribosome biogenesis and induces docetaxel resistance in triple-negative breast cancer cell lines via the miR-340-5p/CMTM6/c-MYC axis

OBJECTIVE

Docetaxel (DTX) represents an effective chemotherapeutic agent for treating triple-negative breast cancer (TNBC), but the efficacy is strongly limited by drug resistance. c-MYC-mediated ribosome biogenesis is considered a feasible strategy to confront chemoresistance in BC. We elucidated the impact of CMTM6 on TNBC DTX chemoresistance by governing c-MYC-mediated ribosome biogenesis, and its upstream ceRNA regulatory pathways.

METHODS

DTX-resistant TNBC cells MDA-MB-231R and HCC1937R were generated by exposing sensitive cells MDA-MB-231 and HCC1937 to escalating doses of DTX. The expression patterns of CMTM6 and c-MYC were assessed by Western blot. The relationships between CMTM6 and miR-340-5p, circUBR5 and miR-340-5p were determined using bioinformatics analysis, luciferase assay, RIP, RNA in situ hybridization and biotin-labeled miR co-precipitation assay. Following ectopic expression and depletion experiments in DTX-resistant cells, cell chemoresistance, apoptosis, colony formation and nascent protein synthesis were evaluated.

RESULTS

CMTM6 expression was elevated in DTX-resistant TNBC cells. CMTM6 knockdown enhanced apoptosis of DTX-resistant TNBC cells and increased their sensitivity to DTX by blocking c-MYC-mediated ribosome biogenesis. Mechanistically, miR-340-5p targeted CMTM6 and negatively regulated the expression of CMTM6 in DTX-resistant TNBC cells. Moreover, circUBR5 attenuated the repression on CMTM6 expression as a ceRNA for miR-340-5p. circUBR5 knockdown inactivated c-MYC-mediated ribosome biogenesis, and therefore enhanced DTX efficacy by promoting miR-340-5p binding to CMTM6.

CONCLUSION

circUBR5 knockdown facilitated miR-340-5p-targeted CMTM6 via a ceRNA mechanism, thereby reducing c-MYC-mediated ribosome biogenesis and accelerating chemosensitization of DTX-resistant TNBC cells, which offered a theoretical guideline for clinical research on the feasibility of inhibiting ribosome biogenesis to reduce TNBC chemoresistance.

The prognostic marker KRT81 is involved in suppressing CD8 + T cells and predicts immunotherapy response for triple-negative breast cancer

Triple-negative breast Cancer (TNBC) is an aggressive subtype lacking estrogen, progesterone, and HER2 receptors. Known for limited targeted therapies, it poses challenges and requires personalized treatment strategies. Differential analysis revealed a significant decrease in keratin 81 (KRT81) expression in non-TNBC samples and an increase in TNBC samples, lower KRT81 expression correlated with better TNBC patient outcomes. It emerged as an independent predictive factor for TNBC, with associations found between its expression and clinically relevant features. We further developed a nomogram for survival probability assessment based on Cox regression results, demonstrating its accuracy through calibration curves. Gene annotation analysis indicated that KRT81 is involved in immune-related pathways and tumor cell adhesion. KRT81 is associated with immune cell infiltration of Follicular helper T cells (Tfh) and CD8 + T cells, suggesting its potential impact on the immunological microenvironment. The study delved into KRT81's predictive value for immunotherapy responses, high expression of KRT81 was associated with greater potential for immune evasion. Single-cell RNA sequencing analysis pinpointed KRT81 expression within a specific malignant subtype which was a risk factor for TNBC. Furthermore, KRT81 promoted TNBC cell proliferation, migration, invasion, and adhesion was confirmed by gene knockout or overexpression assay. Co-culture experiments further indicated KRT81's potential role in inhibiting CD8 + T cells, and correlation analysis implied KRT81 was highly correlated with immune checkpoint CD276, providing insights into its involvement in the immune microenvironment via CD276. In conclusion, this comprehensive study positions KRT81 as a promising prognostic marker for predicting tumor progression and immunotherapy responses in TNBC.

Synthesis of Zinc Oxide-Doped Carbon Dots for Treatment of Triple-Negative Breast Cancer

Introduction

The anti-cancer properties of zinc oxide-doped carbon dots (CDs/ZnO) in inhibiting triple-negative breast cancer (TNBC) progression merit more investigation.

Methods

With citric acid as the carbon source, urea applied as the nitrogen source, and zinc oxide (ZnO) used as a reactive dopant, CDs/ZnO were synthesized by microwave heating in the current study, followed by the characterization and biocompatibility assessments. Subsequently, the anti-cancer capabilities of CDs/ZnO against TNBC progression were evaluated by various biochemical and molecular techniques, including viability, proliferation, migration, invasion, adhesion, clonogenicity, cell cycle distribution, apoptosis, redox homeostasis, metabolome, and transcriptome assays of MDA-MB-231 cells. Additionally, the in vivo anti-cancer potentials of CDs/ZnO against TNBC progression were analyzed using TNBC xenograft mouse models.

Results

The biocompatibility of CDs/ZnO was supported by the non-significant changes in the pathological and physiological parameters in the CDs/ZnO treated mice, alongside a non-cytotoxic effect of CDs/ZnO on the proliferation of normal cells. Notably, the CDs/ZnO treatments effectively decreased the viability, proliferation, migration, invasion, adhesion, and clonogenicity of MDA-MB-231 cells. Furthermore, the CDs/ZnO treatments induced cell cycle arrest, apoptosis, redox imbalance, metabolome disturbances, and transcriptomic alterations of MDA-MB-231 cells by regulating the MAPK signaling pathway. Additionally, the CDs/ZnO treatments markedly suppressed the in vivo tumor growth in the TNBC xenograft mouse models.

Conclusion

In this study, we synthesized CDs/ZnO via microwave heating, using citric acid as the carbon source, urea as the nitrogen source, and ZnO as a reactive dopant. We confirmed the biosafety and potent anti-cancer efficacy of CDs/ZnO in inhibiting TNBC progression by disrupting malignant cell behaviors through modulation of the MAPK signaling pathway.

The splicing machinery is dysregulated and represents a therapeutic vulnerability in breast cancer

Breast cancer (BCa) is a highly prevalent pathological condition (̴30% in women) with limited and subtype-dependent prognosis and therapeutic options. Therefore, BCa management might benefit from the identification of novel molecular elements with clinical potential. Since splicing process is gaining a great relevance in cancer, this work analysed the expression of multiple Spliceosome Components (SCs = 17) and Splicing Factors (SFs = 26) and found a drastic dysregulation in BCa (n = 69) vs. control (negative biopsies; n = 50) samples. Among all the components analysed, we highlight the upregulation of ESRP1 and down-regulation of PRPF8 and NOVA1 in BCa vs. control samples. Indeed, ESRP1 was specially overexpressed in triple-negative BCa (TNBCa) and associated with worse prognosis (i.e., higher BCa grade and lower overall survival), suggesting an association of ESRP1 with BCa aggressiveness. On the other hand, PRPF8 expression was generally downregulated in BCa with no associations to clinical characteristics, while NOVA1 expression was lower in TNBCa patients and highly aggressive tumours. Consistently, NOVA1 overexpression in vitro reduced functional parameters of aggressiveness in ER-/PR- cell lines (MDA-MB-231 and BT-549) but not in ER+/PR+ cells (MCF7), suggesting a critical role of NOVA1 in subtype-specific BCa. Finally, the in vitro pharmacological inhibition of splicing machinery using pladienolide B decreased aggressiveness features in all the BCa cell lines, showing a subtype-independent inhibitory potential, but being relatively innocuous in normal-like breast cells. These results demonstrate the profound dysregulation of the splicing machinery in BCa and their potential as source of promising diagnosis/prognosis markers, as well as valuable therapeutic targets for BCa.

Ethanolic Extract of Averrhoa carambola Leaf Has an Anticancer Activity on Triple-Negative Breast Cancer Cells: An In Vitro Study

Background/Objectives: Averrhoa carambola, or star fruit, is a shrub known for its medicinal properties, especially due to bioactive metabolites identified in its roots and fruit with anti-cancer activity. However, the biological effects of its leaves remain unexplored. This study aimed to assess the effects of ethanolic extract from A. carambola leaves on triple-negative breast cancer (TNBC), an aggressive subtype lacking specific therapy. Methods: Phytochemical analysis and HPLC profile and additional cell line evaluation employing MDA-MB-231 were carried out. Results: Phytochemical screening revealed that the ethanolic extract was rich in flavonoids, saponins, and steroids, demonstrating an antioxidant capacity of 45%. 1H NMR analysis indicated the presence of flavonoids, terpenes, and glycoside-like compounds. Cell viability assays showed a concentration-dependent decrease in viability, with an IC50 value of 20.89 μg/mL at 48 h. Clonogenic assays indicated significant inhibition of replicative immortality, with only 2.63% survival at 15 μg/mL. Migration, assessed through a wound healing assay, was reduced to 3.06% at 100 μg/mL, with only 16.23% of cells remaining attached. An additive effect was observed when combining lower concentrations of the extract with doxorubicin, indicating potential synergy. Conclusions: These results suggest that the ethanolic extract of A. carambola leaves contains metabolites with anti-cancer activity against TNBC cells, supporting further research into their bioactive compounds and therapeutic potential.

Targeting Refractory Triple-Negative Breast Cancer with Sacituzumab Govitecan: A New Era in Precision Medicine

Advanced triple-negative breast cancer (TNBC) has poorer outcomes due to its aggressive behavior and restricted therapeutic options. While therapies like checkpoint inhibitors and PARP inhibitors offer some benefits, chemotherapy remains ineffective beyond the first line of treatment. Antibody-drug conjugates (ADCs) like sacituzumab govitecan-hziy (SG) represent a significant advancement. SG combines SN-38, an irinotecan derivative, with a Trop-2-targeting antibody via a pH-sensitive linking moiety, achieving a good drug:antibody ratio. In a phase I-II study involving metastatic TNBC (mTNBC) individuals, SG achieved an overall response rate of 33.3% and a median response period of 7.7 months. The phase III ASCENT trial demonstrated SG's efficacy in relapsed or refractory TNBC, improving median progression-free survival and median overall survival compared to chemotherapy. Common side effects include neutropenia, nausea, and fatigue. This article highlights the clinical potential, pharmacokinetics, safety profile, and resistance mechanisms of SG along with key ongoing clinical trials, emphasizing its role in managing refractory mTNBC, especially in third-line therapy. The review also discusses current strategies for managing adverse reactions and sequencing ADC treatments in clinical practice, along with the predicted basis of resistance. The optimal sequencing of SG relative to other ADCs, such as trastuzumab deruxtecan or T-DXd, remains an evolving question, especially as newer agents with distinct mechanisms of action and safety profiles enter the field. Further research is essential to establish evidence-based strategies for sequencing SG and addressing disease progression post-ADC therapy.

Transcriptomic analysis reveals potential crosstalk genes and immune relationship between triple-negative breast cancer and depression

TNBC, the most aggressive form of breast cancer, lacks accurate and effective therapeutic targets. Immunotherapy presents a promising approach for addressing TNBC. Anxiety and depression are frequently concurrent symptoms in TNBC patients. MDD affects the tumor immune microenvironment of TNBC, with its characteristic genes affecting the pathophysiology of MDD and potentially increasing the risk of TNBC recurrence and metastasis. This study reveals significant differences in T lymphocyte infiltration between high-risk and low-risk TNBC groups based on MDD feature genes. This finding aids in identifying TNBC patients who may benefit from immunotherapy, providing new insights for future TNBC immunotherapy strategies. Our aim is to identify MDD-related genes involved in the pathogenesis of TNBC and to provide predictive biomarkers for TNBC immunotherapy.