Biology and Management of Patients With Triple-Negative Breast Cancer

Ursolic acid inhibits the proliferation of triple‑negative breast cancer stem‑like cells through NRF2‑mediated ferroptosis

Ursolic acid (UA), a pentacyclic triterpenoid that has been found in a broad variety of fruits, spices and medicinal plants, has various biological effects such as reducing inflammation, protecting cells from damage, and preserving brain function. However, its impact on ferroptosis in cancer stem‑like cells remains unexplored. The present study investigated the effect of UA on MDA‑MB‑231 and BT‑549 cell‑derived triple‑negative breast CSCs (BCSCs) and its potential ferroptosis pathway. The effects of ferroptosis on BCSCs were demonstrated by the detection of ferroptosis‑related indexes including the intracellular level of glutathione, malondialdehyde, reactive oxygen species and iron. The effects of UA on the biological behaviors of BCSCs were analyzed by Cell Counting Kit‑8, stemness indexes detection and mammosphere formation assay. The mechanism of UA induction on BCSCs was explored by reverse transcription‑quantitative PCR and western blotting. BALB/c‑nude mice were subcutaneously injected with MDA‑MB‑231‑derived BCSCs to establish xenograft models to detect the effects of UA in vivo. The results revealed that BCSCs have abnormal iron metabolism and are less susceptible to ferroptosis. UA effectively reduces the stemness traits and proliferation of BCSCs in spheroids and mice models by promoting ferroptosis. It was observed that UA stabilizes Kelch‑like ECH‑associated protein 1 and suppresses nuclear factor erythroid‑related factor 2 (NRF2) activation. These findings suggested that the ability of UA to trigger ferroptosis through the inhibition of the NRF2 pathway could be a promising approach for treating BCSCs, potentially addressing metastasis and drug resistance in triple‑negative breast cancer (TNBC). This expands the clinical applications of UA and provides a theoretical basis for its use in TNBC treatment.

Next-generation biomarkers for prognostic and potential therapeutic enhancement in Triple negative breast cancer

Triple-negative breast carcinoma (TNBC) is one of the most challenging subtypes of breast carcinoma and it has very limited therapeutic options as it is highly aggressive. The prognostic biomarkers are crucial for early diagnosis of the tumor, it also helps in anticipating the trajectory of the illness and optimizing the therapy options. Several therapeutic biomarkers are being used. Among them, the next-generation biomarkers that include ct DNA, glycogen, lipid, and exosome biomarkers provide intriguing opportunities for enhancing the prognosis of TNBC. Lipid and glycogen biomarkers serve as essential details on the development of the tumor along with the efficacy of the treatment, as it exhibits metabolic alteration linked to TNBC. Several types of biomarkers have predictive abilities in TNBC. Elevated levels are associated with worse outcomes. Ct DNA being a noninvasive biomarker reveals the genetic composition of the tumor, as well as helps to monitor the progression of the disease. Traditional therapies are ineffective in TNBC due to a lack of receptors, targeted drug delivery provides a tailored approach to overcome drug resistance and site-specific action by minimizing the side effects in TNBC treatment. This enhances therapeutic outcomes against the aggressive nature of breast cancer. This paper includes all the recent biomarkers which has been researched so far in TNBC and the state of art for TNBC which is explored.

Single-cell analysis of tumor microenvironment and cell adhesion reveals that interleukin-1 beta promotes cancer cell proliferation in breast cancer

BACKGROUND

Triple-negative breast cancer (TNBC), which is so called because of the lack of estrogen receptors (ER), progesterone receptors (PR), and human epidermal growth factor receptor 2 (HER2) receptors on the cancer cells, accounts for 10%-15% of all breast cancers. The heterogeneity of the tumor microenvironment is high. However, the role of plasma cells controlling the tumor migration progression in TNBC is still not fully understood.

METHODS

We analyzed single-cell RNA sequencing data from five HER2 positive, 12 ER positive/PR positive, and nine TNBC samples. The potential targets were validated by immunohistochemistry.

RESULTS

Plasma cells were enriched in TNBC samples, which was consistent with validation using data from The Cancer Genome Atlas. Cell communication analysis revealed that plasma cells interact with T cells through the intercellular adhesion molecule 2-integrin-aLb2 complex, and then release interleukin 1 beta (IL1B), as verified by immunohistochemistry, ultimately promoting tumor growth.

CONCLUSION

Our results revealed the role of plasma cells in TNBC and identified IL1B as a new prognostic marker for TNBC.

The potent potential of MFAP2 in prognosis and immunotherapy of triple-negative breast cancer

BACKGROUNDS

Microfibril-associated protein 2 (MFAP2) is a protein presenting in the extracellular matrix that governs the activity of microfibrils through its interaction with fibrillin. While the involvement of MFAP2 in metabolic disorders has been documented, its expression and prognostic significance in triple-negative breast cancer (TNBC) remain unexplored.

METHODS

We acquired datasets pertaining to breast cancer (BC) from the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases. Next, a Venn diagram was used to identify the differentially expressed genes (DEGs). The DEGs were used to perform Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), protein-protein interaction (PPI), immune and survival analysis. The expressions of MFAP2, PD-1 and PD-L1 were examined by immunohistochemistry and western blot and their relationship with clinical pathological parameters were analyzed by clinical specimen samples from patients with TNBC. Tumor Immune Estimation Resource (TIMER, https://cistrome.shinyapps.io/timer/ ) was adopted to calculate the immune infiltration level of TNBC. The link between gene expression and tumor mutational burden (TMB) was described using Spearman's correlation analysis.

RESULTS

We identified 66 differentially expressed genes (DEGs) that were up-regulated. Among these DEGs, MFAP2 was found to be overexpressed in TNBC and was associated with a lower probability of survival. This finding was confirmed through the use of immunohistochemistry and western blot techniques. Additionally, MFAP2 was found to be related to various pathological parameters in TNBC patients. Mechanistically, gene set enrichment analysis (GSEA) revealed that MFAP2 primarily influenced cellular biological behavior in terms of epithelial mesenchymal transition, glycolysis, and apical junction. Notably, MFAP2 expression was positively correlated with the abundance of macrophages, while a negative correlation was observed with the abundance of B cells, CD4 + T cells, CD8 + T cells, neutrophils and dendritic cells through immune analysis. Furthermore, it was observed that MFAP2 displayed a negative correlation not only with tumor mutational burden (TMB), a recognized biomarker for PD-1/PD-L1 immunotherapy, but also with PD-L1 in samples of TNBC.

CONCLUSION

MFAP2 may be an important prognostic biomarker for TNBC, as well as a viable target for immunotherapy in this disease.

Triple Negative Breast Cancer: Molecular Subtype-Specific Immune Landscapes with Therapeutic Implications

Triple Negative Breast Cancer (TNBC) is characterized by distinct molecular subtypes with unique biological and clinical features. This systematic review aimed to identify articles examining the differences in the tumor immune microenvironment (TIME) across different TNBC molecular subtypes. Six studies meeting inclusion criteria were analyzed, utilizing gene expression profiling and bioinformatic analyses to classify TNBC samples into molecular subtypes, as well as immunohistochemistry and cell deconvolution methods to characterize the TIME. Results revealed significant heterogeneity in immune cell composition among TNBC subtypes, with the immunomodulatory (IM) subtype demonstrating robust immune infiltration, composed mainly of adaptive immune cells along with an increased density of CTLA-4+ and PD-1+ TILs, high PD-L1 tumor cell expression, and upregulation of FOXP3+ Tregs. A more immunosuppressive TIME with a predominance of innate immune cells and lower levels of tumor-infiltrating lymphocytes (TILs) was observed in luminal androgen receptor (LAR) tumors. In mesenchymal stem-like (MSL) tumors, the TIME was mainly composed of innate immune cells, with a high number of M2 tumor-associated macrophages (TAMs), while the BL and M tumors displayed poor adaptive and innate immune responses, indicating an "immune-cold" phenotype. Differential activation of signaling pathways, genomic diversity, and metabolic reprogramming were identified as contributors to TIME heterogeneity. Understanding this interplay is crucial for tailoring therapeutic strategies, especially regarding immunotherapy.

Influence of tumor microenvironment on the different breast cancer subtypes and applied therapies

Despite the significant improvements made in breast cancer therapy during the last decades, this disease still has increasing incidence and mortality rates. Different targets involved in general processes, like cell proliferation and survival, have become alternative therapeutic options for this disease, with some of them already used in clinic, like the CDK4/6 inhibitors for luminal A tumors treatment. Nevertheless, there is a demand for novel therapeutic strategies focused not only on tumor cells, but also on their microenvironment. Tumor microenvironment (TME) is a very complex and dynamic system that, more than surrounding and supporting tumor cells, actively participates in tumor development and progression. During the last decades, it has become clear that the cellular and acellular components of TME differ between the various breast cancer subtypes and shape the differences regarding their severity and prognosis. The pivotal role of the TME in controlling tumor growth and influencing responses to therapy represents a potential source for novel targets and therapeutic strategies. In this review, we present a description of the multiple therapeutic options used for different breast cancer subtypes, as well as the influence that the TME may exert on the development of the disease and on the response to the distinct therapies, which in some cases may explain their failure by the occurrence of relapses and resistance. Furthermore, the ongoing studies focused on the use of TME components for developing potential cancer treatments are described.

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.

The novel circRNA circ_0045881 inhibits cell proliferation and invasion by targeting mir-214-3p in triple-negative breast cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is the most lethal subtype of breast cancer (BC). The circRNA-miRNA‒mRNA axis is a promising biomarker for the early diagnosis and prognosis of BC. However, the critical circRNA mediators involved in TNBC progression and the underlying regulatory mechanism involved remain largely unclear.

METHODS

In this study, we carried out a circRNA microarray analysis of 6 TNBC patients and performed a gene ontology (GO) analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was used to characterize important circRNAs involved in TNBC progression. The interaction between circRNAs and miRNAs was determined by dual luciferase and RNA immunoprecipitation (RIP) assays. Moreover, Transwell, wound healing and Cell Counting Kit-8 (CCK8) assays were performed with altered circRNA or miRNA expression in MDA-MB-231 and BT-549 cells to investigate the roles of these genes in cell invasion, migration and proliferation.

RESULTS

A total of 78 circRNAs were differentially expressed in TNBC tissues, and the hsa_circ_0045881 level was significantly decreased in TNBC tissues and cells. Lentivirus-mediated hsa_circ_0045881 overexpression in MDA-MB-231 and BT-549 cells significantly reduced cell invasion and migration capacity. Additionally, hsa_circ_0045881 interacted with miR-214-3p in MDA-MB-231 cells. miR-214-3p mimics in MDA-MB-231 and BT-549 cells significantly enhanced cell invasion, migration and proliferation, but the other combinations of inhibitors had opposite effects on cell activity.

CONCLUSIONS

Our data indicated that the circRNA has_circ_0045881 plays key roles in TNBC progression and that hsa_circ_0045881 might act as a sponge for miR-214-3p to modulate its levels in TNBC cells, thereby regulating cell invasion, metastasis and proliferation. hsa_circ_004588 might be a potential prognostic marker and therapeutic target for TNBC.

Third-line Treatment for Metastatic Triple-negative Breast Cancer: A Systematic Review and Network Meta-analysis

OBJECTIVE

Metastatic triple-negative breast cancer (mTNBC) is an invasive histologic subtype with a poor prognosis and rapid progression. Currently, there is no standard therapy for the third-line treatment of mTNBC. In this study, we conducted a network meta-analysis to compare regimens and determine treatment outcomes.

METHODS

We performed a systematic search of PubMed, EMBASE, the Cochrane Central Register of Controlled Bases, and the minutes of major conferences. Progression-free survival, overall survival, and objective response rate were analyzed through network meta-analysis using the R software (R Core Team). The efficacy of the treatment regimens was compared using hazard ratios, odds ratios, and 95% CIs.

RESULTS

We evaluated 15 randomized controlled trials involving 6,010 patients. Compared with the physician's choice treatment, sacituzumab govitecan showed significant advantages in progression-free survival and overall survival, with hazard ratio values of 0.41 (95% CI: 0.32-0.52) and 0.48 (95% CI, 0.39-0.60). In terms of objective response rate, sacituzumab govitecan is the best-performing therapy (odds ratio: 10.82; 95% CI: 5.58-20.97). Adverse events among grades 3 to 5 adverse reactions, the incidence of neutropenia and leukopenia in each regimen was higher, whereas the incidence of fever, headache, hypertension, and rash was lower.

CONCLUSION

Compared with the treatment of the physician's choice, sacituzumab govitecan appears more efficacious and is the preferred third-line treatment for mTNBC.

Triple Negative Breast Cancers: An Obsolete Entity?

Triple negative breast cancer is defined on the basis of what it is not. It has served as a useful umbrella entity for management of patients with breast cancer for the last couple of decades. However, during this period a number of novel therapies have become available. These therapies have been documented to be useful in subsets of TNBCs that can be identified on the basis of distinct biologic alterations. Herein we revisit the categorization and usage of the TNBC as an entity to assess its utility in view of the currently available therapies.

An erythrocyte membrane-camouflaged fluorescent covalent organic framework for starving/nitric oxide/immunotherapy of triple-negative breast cancer

It is a great challenge to effectively treat triple-negative breast cancer (TNBC) due to lack of therapeutic targets and drug resistance of systemic chemotherapy. Rational design of nanomedicine with good hemocompatibility is urgently desirable for combination therapy of TNBC. Herein, an erythrocyte membrane-camouflaged fluorescent covalent organic framework (COF) loaded with an NO donor (hydroxyurea, Hu), glucose oxidase (GOx) and cytosine-phosphate-guanine oligonucleotides (CPG) (COF@HGC) was developed for imaging-guided starving/nitric oxide (NO)/immunization synergistic treatment of TNBC. The substances of HGC are easily co-loaded onto the COF due to the ordered pore structure and large surface area. And a folic acid-modified erythrocyte membrane (FEM) is coated on the surface of COF@HGC to improve targeted therapy and haemocompatibility. When COF@HGC@FEM is internalized into tumor cells, hemoglobin (Hb) on FEM and GOx loaded on the COF can trigger cascade reactions to kill tumor cells due to the simultaneous production of NO and exhaustion of glucose. Meanwhile, the COF with excellent fluorescence properties can be used as a self-reporter for bioimaging. Furthermore, the CPG can reprogram tumor-associated macrophages from tumor-supportive phenotype to anti-tumor phenotype and enhance immunotherapy. Through the "three-in-one" strategy, the biomimetic nanoplatform can effectively inhibit tumor growth and reprogram the tumor immunosuppression microenvironment in the TNBC mouse model.

Circ_0004676 exacerbates triple-negative breast cancer progression through regulation of the miR-377-3p/E2F6/PNO1 axis

BACKGROUND

The significant roles of circular RNAs (circRNAs) in different cancers and diseases have been reported. We now focused on the possible role of a newly recognized circRNA, circ_0004674 in triple-negative breast cancer (TNBC), and the related downstream mechanism.

METHODS

The expression of circ_0004674 in TNBC tissues and cells was determined followed by analysis of the correlation between circ_0004674 and TNBC patients' prognosis. The interaction between circ_0004674, miR-377-3p, E2F6, and PNO1 was then identified using bioinformatics analysis combined with FISH, RIP, RNA pull-down, RT-qPCR, and Western blot analysis. Using gain-of-function and loss-of-function methods, we analyzed the effect of circ_0004674, miR-377-3p, E2F6, and PNO1 on TNBC in vivo and in vitro.

RESULTS

Increased circ_0004674 and E2F6 but decreased miR-377-3p were observed in TNBC tissues and MDA-MB-231 TNBC cells, all of which findings were associated with poor prognosis in patients with TNBC. Silencing of circ_0004676 remarkably suppressed the proliferation, cell cycle progression, and migration of TNBC cells in vitro, as well as inhibiting tumorigenesis and metastasis in vivo. Additionally, circ_0004676 served as a sponge of miR-377-3p which bound to the transcription factor E2F6. In the presence of overexpression of circ_0004676, E2F6 expression and its target PNO1 expression were elevated, while miR-377-3p expression was decreased. Interestingly, overexpression of E2F6 could reverse the inhibitory effect on tumor growth caused by downregulation of circ_0004676.

CONCLUSION

Our study highlighted the carcinogenic effect of circ_0004676 on TNBC through regulation of the miR-377-3p/E2F6/PNO1 axis. 1. Circ_0004674 is highly expressed in TNBC tissues and cells. 2. Circ_0004674 upregulates the expression of E2F6 by sponging miR-377-3p. 3. E2F6 upregulates PNO1 by binding to the PNO1 promoter. 4. Circ_0004674 favors TNBC progression by regulating the miR-377-3p/E2F6/PNO1 axis. 5. This study provides a new target for the treatment of TNBC.

Advances in the application of computational pathology in diagnosis, immunomicroenvironment recognition, and immunotherapy evaluation of breast cancer: a narrative review

BACKGROUND

Breast cancer (BC) is a prevalent and highly lethal malignancy affecting women worldwide. Immunotherapy has emerged as a promising therapeutic strategy for BC, offering potential improvements in patient survival. Neoadjuvant therapy (NAT) has also gained significant clinical traction. With the advancement of computer technology, Artificial Intelligence (AI) has been increasingly applied in pathology research, expanding and redefining the scope of the field. This narrative review aims to provide a comprehensive overview of the current literature on the application of computational pathology in BC, specifically focusing on diagnosis, immune microenvironment recognition, and the evaluation of immunotherapy and NAT response.

METHODS

A thorough examination of relevant literature was conducted, focusing on studies investigating the role of computational pathology in BC diagnosis, immune microenvironment recognition, and immunotherapy and NAT assessment.

RESULTS

The application of computational pathology has shown significant potential in BC management. AI-based techniques enable improved diagnosis and classification of BC subtypes, enhance the identification and characterization of the immune microenvironment, and facilitate the evaluation of immunotherapy and NAT response. However, challenges related to data quality, standardization, and algorithm development still need to be addressed.

CONCLUSION

The integration of computational pathology and AI has transformative implications for BC patient care. By leveraging AI-based technologies, clinicians can make more informed decisions in diagnosis, treatment planning, and therapeutic response assessment. Future research should focus on refining AI algorithms, addressing technical challenges, and conducting large-scale clinical validation studies to facilitate the translation of computational pathology into routine clinical practice for BC patients.

Phenotypic heterogeneity drives differential disease outcome in a mouse model of triple negative breast cancer

The triple negative breast cancer (TNBC) subtype is one of the most aggressive forms of breast cancer that has poor clinical outcome and is an unmet clinical challenge. Accumulating evidence suggests that intratumoral heterogeneity or the presence of phenotypically distinct cell populations within a tumor play a crucial role in chemoresistance, tumor progression and metastasis. An increased understanding of the molecular regulators of intratumoral heterogeneity is crucial to the development of effective therapeutic strategies in TNBC. To this end, we used an unbiased approach to identify a molecular mediator of intratumoral heterogeneity in breast cancer by isolating two tumor cell populations (T1 and T2) from the 4T1 TNBC model. Phenotypic characterization revealed that the cells are different in terms of their morphology, proliferation and self-renewal ability in vitro as well as primary tumor formation and metastatic potential in vivo. Bioinformatic analysis followed by Kaplan Meier survival analysis in TNBC patients identified Metastasis associated colon cancer 1 (Macc1) as one of the top candidate genes mediating the aggressive phenotype in the T1 tumor cells. The role of Macc1 in regulating the proliferative phenotype was validated and taken forward in a therapeutic context with Lovastatin, a small molecule transcriptional inhibitor of Macc1 to target the T1 cell population. This study increases our understanding of the molecular underpinnings of intratumoral heterogeneity in breast cancer that is critical to improve the treatment of women currently living with the highly aggressive TNBC subtype.

Molecular Biology Mechanisms and Emerging Therapeutics of Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that is conventionally characterized by the absence of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2), accounting for approximately 15-20% of all breast cancers. Compared to other molecular phenotypes, TNBC is typically associated with high malignancy and poor prognosis. Cytotoxic agents have been the mainstay of treatment for the past few decades due to the lack of definitive targets and limited therapeutic interventions. However, recent developments have demonstrated that TNBC has peculiar molecular classifications and biomarkers, which provide the possibility of evolving treatment from basic cytotoxic chemotherapy to an expanding domain of targeted therapies. This review presents a framework for understanding the current clinical experience surrounding molecular biology mechanisms in TNBC (Figure 1). Including immunotherapy, polymerase (PARP) and PI3K/AKT pathway inhibitors, antibody-drug conjugates, and androgen receptor (AR) blockade. Additionally, the role of miRNA therapeutics targeting TNBC and potential strategies targeting cancer stem cells (CSCs) are discussed and highlighted. As more and more treatments arise on the horizon, we believe that patients with TNBC will have a new sense of hope.

Xianlinglianxiafang Inhibited the growth and metastasis of triple-negative breast cancer via activating PPARγ/AMPK signaling pathway

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer characterized by high invasion and metastasis rates. Xian-Ling-Lian-Xia formula (XLLX) is a traditional Chinese medicine prescription widely used in China for treating TNBC. Clinical studies have shown that XLLX significantly reduces the recurrence and metastasis rate of TNBC and improves disease-free survival. However, the potential molecular mechanisms of XLLX on TNBC are not clear yet. Here, we investigated the effects of XLLX on TNBC using a mouse model and tumor cell lines. The results showed that XLLX significantly inhibited the proliferation, migration, and invasion abilities of TNBC cell lines MDA-MB-231 and 4T1 in vitro, induced apoptosis, and regulated the expression of proliferation, apoptosis, and EMT marker proteins in tumor cells. In in vivo experiments, XLLX treatment significantly reduced the progression of TNBC tumors and lung metastasis. Transcriptomics reveals that XLLX treatment significantly enriched differentially expressed genes in the peroxisome proliferator-activated receptor gamma (PPARγ) and AMP-dependent protein kinase (AMPK) signaling pathways. The western blot results confirmed that XLLX significantly upregulated the protein expression of PPARγ and p-AMPK in TNBC cells, tumors, and lung tissues. It is noteworthy that GW9662 (a PPARγ inhibitor) and Compound C (an AMPK inhibitor) partially reversed the anti-proliferation and anti-metastasis effects of XLLX in TNBC cells. Therefore, XLLX may effectively inhibit the growth and metastasis of TNBC by activating the PPARγ/AMPK signaling pathway.

A meta-analysis of application of PD-1/PD-L1 inhibitor-based immunotherapy in unresectable locally advanced triple-negative breast cancer

Aims: The purpose of this study was to explore the efficacy of immunotherapy for patients with triple-negative breast cancer (TNBC). Materials & methods: Randomized clinical trials comparing immunotherapy with chemotherapy for advanced TNBC patients were included. Results: A total of six articles (3183 patients) were eligible for this meta-analysis. PD-1/PD-L1 inhibitor-based immunotherapy combined with chemotherapy can significantly increase the progression-free survival (hazard ratio [HR] = 0.82; 95% CI = 0.76-1.14; p < 0.001) of unresectable locally advanced or metastatic TNBC patients without effect on overall survival, compared with chemotherapy. Conclusion: PD-1/PD-L1 inhibitors-based immunotherapy can safely improve progression-free survival in patients with unresectable locally advanced or metastatic TNBC, but has no effect on overall survival.

SP1-Induced Upregulation of LncRNA AFAP1-AS1 Promotes Tumor Progression in Triple-Negative Breast Cancer by Regulating mTOR Pathway

The long non-coding RNA (lncRNA) actin fiber-associated protein-1 antisense RNA 1 (AFAP1-AS1) exerted oncogenic activity in triple-negative breast cancer (TNBC). We designed this study and conducted it to investigate the upstream regulation mechanism of AFAP1-AS1 in TNBC tumorigenesis. In this work, we proved the localization of AFAP1-AS1 in the cytoplasm. We elucidated the mechanism by which the transcription factor specificity protein 1 (SP1) modulated AFAP1-AS1 in TNBC progression, which has yet to be thoroughly studied. Dual luciferase reporter assay and chromatin immunoprecipitation (ChIP) assay revealed a strong affinity of SP1 toward the promoter regions P3 of AFAP1-AS1, proving the gene expression regulation of AFAP1-AS1 via SP1 in TNBC. Additionally, SP1 could facilitate the tumorigenesis of TNBC cells in vitro and in vivo by regulating the AFAP1-AS1 expression. Furthermore, silenced AFAP1-AS1 suppressed the expression of genes in the mTOR pathway, such as eukaryotic translation initiation factor 4B (EIF4B), mitogen-activated protein kinase-associated protein 1 (MAPKAP1), SEH1-like nucleoporin (SEH1L), serum/glucocorticoid regulated kinase 1 (SGK1), and its target NEDD4-like E3 ubiquitin protein ligase (NEDD4L), and promoted the gene expression of s-phase kinase-associated protein 2 (SKP2). Overall, this study emphasized the oncogenic role of SP1 and AFAP1-AS1 in TNBC and illustrated the AFAP1-AS1 upstream interaction with SP1 and the downstream modulatory of mTOR signaling, thus offering insights into the tumorigenesis mechanism in TNBC.

ETS-1-activated LINC01016 over-expression promotes tumor progression via suppression of RFFL-mediated DHX9 ubiquitination degradation in breast cancers

Long non-coding RNAs (lncRNAs) are key regulators during the development of breast cancer (BC) and thus may be viable treatment targets. In this study, we found that the expression of the long intergenic non-coding RNA 01016 (LINC01016) was significantly higher in BC tissue samples with positive lymph node metastasis. LINC01016, which is activated by the transcription factor ETS-1, contributes to the overt promotion of cell proliferation activity, enhanced cell migratory ability, S phase cell cycle arrest, and decreased apoptosis rate. By RNA pull-down assays and mass spectrometry analyses, we determined that LINC01016 competitively bound and stabilized DHX9 protein by preventing the E3 ubiquitin ligase RFFL from binding to DHX9, thereby inhibiting DHX9 proteasomal degradation. This ultimately led to an increase in intracellular DHX9 expression and activated PI3K/AKT signaling, with p-AKT, Bcl-2, and MMP-9 involvement. This is the first study to reveal that the LINC01016/DHX9/PI3K/AKT axis plays a critical role in the progression of BC, and thus, LINC01016 may serve as a potential therapeutic target for patients with BC.

CSF2 upregulates CXCL3 expression in adipocytes to promote metastasis of breast cancer via the FAK signaling pathway

Recent studies have demonstrated that cancer-associated adipocytes (CAAs) in the tumor microenvironment are involved in the malignant progression of breast cancer. However, the underlying mechanism of CAA formation and its effects on the development of breast cancer are still unknown. Here, we show that CSF2 is highly expressed in both CAAs and breast cancer cells. CSF2 promotes inflammatory phenotypic changes of adipocytes through the Stat3 signaling pathway, leading to the secretion of multiple cytokines and proteases, particularly C-X-C motif chemokine ligand 3 (CXCL3). Adipocyte-derived CXCL3 binds to its specific receptor CXCR2 on breast cancer cells and activates the FAK pathway, enhancing the mesenchymal phenotype, migration, and invasion of breast cancer cells. In addition, a combination treatment targeting CSF2 and CXCR2 shows a synergistic inhibitory effect on adipocyte-induced lung metastasis of mouse 4T1 cells in vivo. These findings elucidate a novel mechanism of breast cancer metastasis and provide a potential therapeutic strategy for breast cancer metastasis.

A Radiomics Model Based on Synthetic MRI Acquisition for Predicting Neoadjuvant Systemic Treatment Response in Triple-Negative Breast Cancer

Purpose To determine if a radiomics model based on quantitative maps acquired with synthetic MRI (SyMRI) is useful for predicting neoadjuvant systemic therapy (NAST) response in triple-negative breast cancer (TNBC). Materials and Methods In this prospective study, 181 women diagnosed with stage I-III TNBC were scanned with a SyMRI sequence at baseline and at midtreatment (after four cycles of NAST), producing T1, T2, and proton density (PD) maps. Histopathologic analysis at surgery was used to determine pathologic complete response (pCR) or non-pCR status. From three-dimensional tumor contours drawn on the three maps, 310 histogram and textural features were extracted, resulting in 930 features per scan. Radiomic features were compared between pCR and non-pCR groups by using Wilcoxon rank sum test. To build a multivariable predictive model, logistic regression with elastic net regularization and cross-validation was performed for texture feature selection using 119 participants (median age, 52 years [range, 26-77 years]). An independent testing cohort of 62 participants (median age, 48 years [range, 23-74 years]) was used to evaluate and compare the models by area under the receiver operating characteristic curve (AUC). Results Univariable analysis identified 15 T1, 10 T2, and 12 PD radiomic features at midtreatment that predicted pCR with an AUC greater than 0.70 in both the training and testing cohorts. Multivariable radiomics models of maps acquired at midtreatment demonstrated superior performance over those acquired at baseline, achieving AUCs as high as 0.78 and 0.72 in the training and testing cohorts, respectively. Conclusion SyMRI-based radiomic features acquired at midtreatment are potentially useful for identifying early NAST responders in TNBC. Keywords: MR Imaging, Breast, Outcomes Analysis ClinicalTrials.gov registration no. NCT02276443 Supplemental material is available for this article. © RSNA, 2023 See also the commentary by Houser and Rapelyea in this issue.

Comprehensively analysis of immunophenotyping signature in triple-negative breast cancer patients based on machine learning

Immunotherapy is a promising strategy for triple-negative breast cancer (TNBC) patients, however, the overall survival (OS) of 5-years is still not satisfactory. Hence, developing more valuable prognostic signature is urgently needed for clinical practice. This study established and verified an effective risk model based on machine learning methods through a series of publicly available datasets. Furthermore, the correlation between risk signature and chemotherapy drug sensitivity were also performed. The findings showed that comprehensive immune typing is highly effective and accurate in assessing prognosis of TNBC patients. Analysis showed that IL18R1, BTN3A1, CD160, CD226, IL12B, GNLY and PDCD1LG2 are key genes that may affect immune typing of TNBC patients. The risk signature plays a robust ability in prognosis prediction compared with other clinicopathological features in TNBC patients. In addition, the effect of our constructed risk model on immunotherapy response was superior to TIDE results. Finally, high-risk groups were more sensitive to MR-1220, GSK2110183 and temsirolimus, indicating that risk characteristics could predict drug sensitivity in TNBC patients to a certain extent. This study proposes an immunophenotype-based risk assessment model that provides a more accurate prognostic assessment tool for patients with TNBC and also predicts new potential compounds by performing machine learning algorithms.

Apatinib plus etoposide in pretreated patients with advanced triple-negative breast cancer: a phase II trial

BACKGROUND

Treatment options for pretreated triple-negative breast cancer (TNBC) are limited. This study aimed to evaluate the efficacy and safety of apatinib, an antiangiogenic agent, in combination of etoposide for pretreated patients with advanced TNBC.

METHODS

In this single-arm phase II trial, patients with advanced TNBC who failed to at least one line of chemotherapy were enrolled. Eligible patients received oral apatinib 500 mg on day 1 to 21, plus oral etoposide 50 mg on day 1 to 14 of a 3-week cycle until disease progression or intolerable toxicities. Etoposide was administered up to six cycles. The primary endpoint was progression-free survival (PFS).

RESULTS

From September 2018 to September 2021, 40 patients with advanced TNBC were enrolled. All patients received previous chemotherapy in the advanced setting, with the median previous lines of 2 (1-5). At the cut-off date on January 10, 2022, the median follow-up was 26.8 (1.6-52.0) months. The median PFS was 6.0 (95% confidence interval [CI]: 3.8-8.2) months, and the median overall survival was 24.5 (95%CI: 10.2-38.8) months. The objective response rate and disease control rate was 10.0% and 62.5%, respectively. The most common adverse events (AEs) were hypertension (65.0%), nausea (47.5%) and vomiting (42.5%). Four patients developed grade 3 AE, including two with hypertension and two with proteinuria.

CONCLUSIONS

Apatinib combined with oral etoposide was feasible in pretreated advanced TNBC, and was easy to administer.

CLINICAL TRIAL REGISTRATION

Chictr.org.cn, (registration number: ChiCTR1800018497, registration date: 20/09/2018).

Synthesis and biological evaluation of atropisomeric tetrahydroisoquinolines overcoming docetaxel resistance in triple-negative human breast cancer cells

Herein, atropisomeric 8-aryltetrahydroisoquinolines have been synthesized and biologically evaluated. Based on our structure-activity relationship study, a highly bioactive racemic compound has been produced, and it exhibited high antiproliferative activities against various cancer cell lines, including docetaxel-resistant breast cancer cell lines. Each enantiomer can be synthesized in an enantioselective manner by employing the chiral phosphoric acid-catalyzed atroposelective Pictet-Spengler cyclization. An axially (R)-configured enantiomer showed a higher biological activity compared with the axially (S)-configured enantiomer. Further biological studies suggested that the (R)-enantiomer overcomes docetaxel resistance via the downregulation of signal transducer and activator of transcription 3 activation and consequently induces cellular apoptosis in docetaxel-resistant triple-negative breast cancer cell lines.

Exploring paclitaxel-loaded adenosine-conjugated PEGylated PLGA nanoparticles for targeting triple-negative breast cancer

In present investigation, we developed paclitaxel (PTX)-loaded adenosine (ADN)-conjugated PLGA nanoparticles for combating triple-negative breast cancer (TNBC), where ADN acts as a substrate for adenosine receptors (AR) that are overexpressed in TNBC. Using synthesized PLGA-PEG-ADN, PTX-loaded nanoparticles (PTX ADN-PEG-PLGA NPs) were prepared via emulsion diffusion evaporation process that rendered particles of size 135 ± 12 nm, PDI of 0.119 ± 0.03, and entrapment-efficiency of 79.26 ± 2.52%. The NPs showed higher %cumulative release at pH 5.5 over 7.4 with Higuchi release kinetics. The PTX ADN-PEG-PLGA NPs showed ~ 4.87- and 5.22-fold decrease in %hemolysis in comparison to free PTX and Intaxel^®, indicating their hemocompatible nature. The ADN modification assisted cytoplasmic internalization of particles via AR-mediated endocytosis that resulted in ~ 3.77- and 3.51-fold reduction in IC₅₀ and showed apoptosis index of 0.93 and 1.18 in MDA-MB-231 and 4T1 cells respectively. The pharmacokinetic profile of ADN-PEG-PLGA NPs revealed higher AUC and t1/2 than Intaxel^® and Nanoxel^® pharmacodynamic activity showed ~ 18.90-fold lower %tumor burden than control. The kidney and liver function biomarkers showed insignificant change in the levels, when treated with PTX ADN-PEG-PLGA NPs and exhibited no histological alterations in the liver, spleen, and kidney. Overall, the optimized particles were found to be biocompatible with improved anti-TNBC activity.

Design of novel polyurethane-based ionene nanocarriers for cancer therapy: Synthesis, in-vitro, and in-vivo studies

New strategies for constructing versatile nanocarriers are needed for cancer therapy to overcome the multiple challenges of targeted delivery. This work explores the advantages of polyurethane with main-chain quaternary ammonium salt moieties (ionene) as a novel carrier for targeted drug delivery. We have developed a novel cationic soybean oil-based polyurethane ionene nanocarrier (CPUI) that can act as an effective anticancer agent and efficiently deliver the anticancer drug 5-fluorouracil (5FU). We also report a potential anticancer drug delivery system targeting the folate receptor. In vitro experiments with blank CPUI carriers on the 4T1 (mouse breast cancer cell line) and the NIH-3T3 (mouse fibroblast cell line) revealed high cytotoxicity for the cancer cells but only low cytotoxicity for the normal fibroblast cells. The CPUI nanoparticles were readily loaded with 5FU (5FU-CPUI) in water using electrostatic interactions between the cationic quaternary ammonium groups of ionene and the anionic 5FU. The in vivo study in mice with tumors showed that the blank CPUI carriers significantly inhibited tumor growth, even more than the free drug (5FU). The inhibitory effect on tumor growth was slightly enhanced when the carriers were loaded with 5FU. The prepared nanoparticles had a high loading capacity of 41.8 %. Further enhancement of the inhibitory effect was observed when folic acid (FA) was added as a targeting moiety to the system via ion exchange with the bromine counterion of the quaternary ammonium moieties. The results suggest that the efficacy of FA-CPUI-5FU nanoparticles as vehicles for drug delivery can be enhanced via folate receptor (FR) mediated endocytosis in 4T1 cells and these novel nanocarriers may provide a potential platform for effective targeted drug delivery to tumor tissue and breast cancer therapy in the clinic.

Model for predicting immunotherapy based on M2 macrophage infiltration in TNBC

Introduction

Compared to other types of breast cancer, triple-negative breast cancer (TNBC) does not effectively respond to hormone therapy and HER2 targeted therapy, showing a poor prognosis. There are currently a limited number of immunotherapeutic drugs available for TNBC, a field that requires additional development.

Methods

Co-expressing genes with M2 macrophages were analyzed based on the infiltration of M2 macrophages in TNBC and the sequencing data in The Cancer Genome Atlas (TCGA) database. Consequently, the influence of these genes on the prognoses of TNBC patients was analyzed. GO analysis and KEGG analysis were performed for exploring potential signal pathways. Lasso regression analysis was conducted for model construction. The TNBC patients were scored by the model, and patients were divided into high- and low-risk groups. Subsequently, the accuracy of model was further verified using GEO database and patients information from the Cancer Center of Sun Yat-sen University. On this basis, we analyzed the accuracy of prognosis prediction, correlation with immune checkpoint, and immunotherapy drug sensitivity in different groups.

Results

Our findings revealed that OLFML2B, MS4A7, SPARC, POSTN, THY1, and CD300C genes significantly influenced the prognosis of TNBC. Moreover, MS4A7, SPARC, and CD300C were finally determined for model construction, and the model showed good accuracy in prognosis prediction. And 50 immunotherapy drugs with therapeutic significance in different groups were screened, which were assessed possible immunotherapeutics that have potential application and demonstrated the high precision of our prognostic model for predictive analysis.

Conclusion

MS4A7, SPARC, and CD300C, the three main genes used in our prognostic model, offer good precision and clinical application potential. Fifty immune medications were assessed for their ability to predict immunotherapy drugs, providing a novel approach to immunotherapy for TNBC patients and a more reliable foundation for applying drugs in subsequent treatments.

Intratumoral CD8+ T cells with a tissue-resident memory phenotype mediate local immunity and immune checkpoint responses in breast cancer

CD8⁺ tumor-infiltrating lymphocytes with a tissue-resident memory T (T_RM) cell phenotype are associated with favorable prognosis in patients with triple-negative breast cancer (TNBC). However, the relative contribution of CD8⁺ T_RM cells to anti-tumor immunity and immune checkpoint blockade efficacy in breast cancer remains unknown. Here, we show that intratumoral CD8⁺ T cells in murine mammary tumors transcriptionally resemble those from TNBC patients. Phenotypic and transcriptional studies established two intratumoral sub-populations: one more enriched in markers of terminal exhaustion (T_EX-like) and the other with a bona fide resident phenotype (T_RM-like). Treatment with anti-PD-1 and anti-CTLA-4 therapy resulted in expansion of these intratumoral populations, with the T_RM-like subset displaying significantly enhanced cytotoxic capacity. T_RM-like CD8⁺ T cells could also provide local immune protection against tumor rechallenge and a T_RM gene signature extracted from tumor-free tissue was significantly associated with improved clinical outcomes in TNBC patients treated with checkpoint inhibitors.

GLIS Family Zinc Finger 3 Promotes Triple-Negative Breast Cancer Progression by Inducing Cell Proliferation, Migration and Invasion, and Activating the NF-κB Signaling Pathway

Triple-negative breast cancer (TNBC) puts a great threat to women's health. GLIS family zinc finger 3 (GLIS3) belongs to the GLI transcription factor family and acts as a critical factor in cancer progression. Nevertheless, the part of GLIS3 played in TNBC is not known. Immunohistochemical (IHC) staining analysis displayed that GLIS3 was highly expressed in TNBC tissues. The effect of GLIS3 on the malignant phenotype of TNBC was tested in two different cell lines according to GLIS3 regulation. Upregulation of GLIS3 promoted the proliferation, migration, and invasion of TNBC cell lines, whereas the knockdown of GLIS3 suppressed these tumor activities. Inhibition of GLIS3 induced TNBC cell apoptosis. Furthermore, study as immunofluorescence and electrophoretic mobility shift assay confirmed that the nuclear factor-κB (NF-κB) signaling pathway activated by GLIS3 played an important role in TNBC cells' malignant phenotype. In conclusion, the present work demonstrated that GLIS3 acts as a crucial element in TNBC progression via activating the NF-κB signaling pathway. Accordingly, above mentioned findings indicated that modulation of GLIS3 expression is a potential tactic to interfere with the progression of TNBC.

Transcriptomic profiles-based approach to decode the role of miR-122 in triple negative breast cancer

miR-122 has been considered both as tumor suppressor miRNA and oncomiR in breast tumor phenotypes. However, the role of miR-122 in triple-negative breast cancer (TNBC) is still unknown. In this study, the clinical value of miR-122 was used to describe the transcriptomic landscape of TNBC tumors obtained from The Cancer Genome Atlas database. Low expression levels of miR-122 were associated with poor overall survival (OS) of TNBC patients than those with higher expression levels of miR-122. We identified gene expression profiles in TNBC tumors expressed lower or higher miR-122. Gene coexpression networks analysis revealed gene modules and hub genes specific to TNBC tumors with low or high miR-122 levels. Gene ontology and KEGG pathways analysis revealed that gene modules in TNBC with gain of miR-122 were related to cell cycle and DNA repair, while in TNBC with loss of miR-122 were enriched in cell cycle, proliferation, apoptosis and activation of cell migration and invasion. The expression of hub genes distinguished TNBC tumors with gain or loss of miR-122 from normal breast tissues. Furthermore, high levels of hub genes were associated with better OS in TNBC patients. Interestingly, the gene coexpression network related to loss of miR-122 were enriched with target genes of miR-122, but this did not observed in those with gain of miR-122. Target genes of miR-122 are oncogenes mainly associated with cell differentiation-related processes. Finally, 75 genes were identified exclusively associated to loss of miR-122, which are also implicated in cell differentiation. In conclusion, miR-122 could act as tumor suppressor by controlling oncogenes in TNBC.

Assessing the pathogenicity of BRCA1/2 variants of unknown significance: Relevance and challenges for breast cancer precision medicine

Introduction

Breast cancer (BC) is the leading cause of cancer-related death in women worldwide. Pathogenic variants in BRCA1 and BRCA2 genes account for approximately 50% of all hereditary BC, with 60-80% of patients characterized by Triple Negative Breast Cancer (TNBC) at an early stage phenotype. The identification of a pathogenic BRCA1/2 variant has important and expanding roles in risk-reducing surgeries, treatment planning, and familial surveillance. Otherwise, finding unclassified Variants of Unknown Significance (VUS) limits the clinical utility of the molecular test, leading to an "imprecise medicine".

Methods

We reported the explanatory example of the BRCA1 c.5057A>C, p.(His1686Pro) VUS identified in a patient with TNBC. We integrated data from family history and clinic-pathological evaluations, genetic analyses, and bioinformatics in silico investigations to evaluate the VUS classification.

Results

Our evaluation posed evidences for the pathogenicity significance of the investigated VUS: 1) association of the BRCA1 variant to cancer-affected members of the family; 2) absence of another high-risk mutation; 3) multiple indirect evidences derived from gene and protein structural analysis.

Discussion

In line with the ongoing efforts to uncertain variants classification, we speculated about the relevance of an in-depth assessment of pathogenicity of BRCA1/2 VUS for a personalized management of patients with BC. We underlined that the efficient integration of clinical data with the widest number of supporting molecular evidences should be adopted for the proper management of patients, with the final aim of effectively guide the best prognostic and therapeutic paths.

Using global feedback to induce learning of gist of abnormality in mammograms

Extraction of global structural regularities provides general 'gist' of our everyday visual environment as it does the gist of abnormality for medical experts reviewing medical images. We investigated whether naïve observers could learn this gist of medical abnormality. Fifteen participants completed nine adaptive training sessions viewing four categories of unilateral mammograms: normal, obvious-abnormal, subtle-abnormal, and global signals of abnormality (mammograms with no visible lesions but from breasts contralateral to or years prior to the development of cancer) and receiving only categorical feedback. Performance was tested pre-training, post-training, and after a week's retention on 200 mammograms viewed for 500 ms without feedback. Performance measured as d' was modulated by mammogram category, with the highest performance for mammograms with visible lesions. Post-training, twelve observed showed increased d' for all mammogram categories but a subset of nine, labelled learners also showed a positive correlation of d' across training. Critically, learners learned to detect abnormality in mammograms with only the global signals, but improvements were poorly retained. A state-of-the-art breast cancer classifier detected mammograms with lesions but struggled to detect cancer in mammograms with the global signal of abnormality. The gist of abnormality can be learned through perceptual/incidental learning in mammograms both with and without visible lesions, subject to individual differences. Poor retention suggests perceptual tuning to gist needs maintenance, converging with findings that radiologists' gist performance correlates with the number of cases reviewed per year, not years of experience. The human visual system can tune itself to complex global signals not easily captured by current deep neural networks.

Kaiso Protein Expression Correlates with Overall Survival in TNBC Patients

Triple-negative breast cancers (TNBCs) are histologically heterogenic invasive carcinomas of no specific type that lack distinctive histological characteristics. The prognosis for women with TNBC is poor. Regardless of the applied treatments, recurrences and deaths are observed 3-5 years after the diagnosis. Thus, new diagnostic markers and targets for personalized treatment are needed. The subject of our study-the Kaiso transcription factor has been found to correlate with the invasion and progression of breast cancer. The publicly available TCGA breast cancer cohort containing Illumina HiSeq RNAseq and clinical data was explored in the study. Additionally, Kaiso protein expression was assessed in formalin-fixed and paraffin-embedded tissue archive specimens using the tissue microarray technique. In this retrospective study, Kaiso protein expression (nuclear localization) was compared with several clinical factors in the cohort of 103 patients with TNBC with long follow-up time. In univariate and multivariate analysis, high Kaiso protein but not mRNA expression was correlated with better overall survival and disease-free survival, as well as with premenopausal age. The use of radiotherapy was correlated with better disease-free survival (DFS) and overall survival (OS). However, given the heterogeneity of TNBC and context-dependent molecular diversity of Kaiso signaling in cancer progression, these results must be taken with caution and require further studies.

Breast carcinogenesis induced by organophosphorous pesticides

Breast cancer is a major health threat to women worldwide and the leading cause of cancer-related death. The use of organophosphorous pesticides has increased in agricultural environments and urban settings, and there is evidence that estrogen may increase breast cancer risk in women. The mammary gland is an excellent model for examining its susceptibility to different carcinogenic agents due to its high cell proliferation capabilities associated with the topography of the mammary parenchyma and specific stages of gland development. Several experimental cellular models are presented here, in which the animals were exposed to chemical compounds such as pesticides, and endogenous substances such as estrogens that exert a significant effect on normal breast cell processes at different levels. Such models were developed by the effect of malathion, parathion, and eserine, influenced by estrogen demonstrating features of cancer initiation in vivo as tumor formation in rodents; and in vitro in the immortalized normal breast cell line MCF-10F, that when transformed showed signs of carcinogenesis such as increased cell proliferation, anchorage independence, invasive capabilities, modulation of receptors and genomic instability. The role of acetylcholine was also demonstrated in the MCF-10F, suggesting a role not only as a neurotransmitter but also with other functions, such as induction of cell proliferation, playing an important role in cancer. Of note, this is a unique experimental approach that identifies mechanistic signs that link organophosphorous pesticides with breast carcinogenesis.

BIRTH OF A GLYCOTHERAPY FOR BREAST CANCER

Breast cancer is the most common malignant disease in women and is worldwide. The incidence rate of women's breast cancer in 2020 was 2,261,419 and 2022 estimates diagnosing 1,918,030 cases. The disease is heterogeneous and the pathogenesis of breast cancer still remains unclear. Much progress has been made in early detection and better treatment to improve survival. Unfortunately, the current treatment strategies destroy the patient's quality of life. The patients develop drug resistance, exhibit severe side effects, and not afford the cost creates anxiety among the patients, families, and friends. In addition, a considerable number of patients relapse as a result of organ metastasis, e.g., the triple-negative breast cancer (TNBC, ER-/PR-HER2-). The 5-year survival rate of patients who recurred with distant metastasis is less than 20%. More than half a million women worldwide still suffer from metastatic breast cancer annually, and 90% of their deaths could be attributed to metastasis. One of the reasons for the failure of cancer therapeutics is the approaches did not consider the cancer holistically. All breast cancer cells and their micro environmental capillary endothelial cells express asparagine-linked (N-linked) glycoproteins. We have tested a biologic and a small molecule, Tunicamycin-P (P = pure N-glycosylation inhibitor) to interfere with the protein N-glycosylation pathway in the endoplasmic reticulum (ER) by specifically blocking the catalytic activity of N-acetylglusosaminyl 1-phosphate transferase (GPT) activity. The outcome has been quantitative inhibition of in vitro and in vivo angiogenesis and the breast tumor progression of multiple subtypes in pre-clinical mouse models with "zero" toxicity. We have, therefore, concluded that Tunicamycin-P is expected to supersede the current therapeutics and become a Glycotherapy treating breast cancer of all subtypes.

Characterization of triple negative breast cancer gene expression profiles in Mexican patients

Triple negative breast cancer (TNBC) is an aggressive type of cancer that accounts for ~23% of breast tumors in Mexico. In an attempt to understand in an improved way the behavior of TNBC, throughout the years, gene expression in these tumors has been studied. Lehman et al identified 6 subtypes of gene expression in TNBC with distinct characteristics. In the present study, it was aimed to assess clinical, pathological and prognostic characteristics of TNBC in a Mexican-based cohort. A total of 55 patients diagnosed with TNBC at Mexico's National Institute of Cancer (INCan) were included. Tumor needle biopsy samples were obtained and subjected to microarray analysis. Patients were thus classified into one of the 6 TNBC molecular subtypes. The prognostic, clinical and pathological information of patients was obtained, and differences across molecular subtypes were sought. Out of the 55 included patients, the following subtypes were identified: 9 basal-like-1, 11 basal-like-2 (BSL2), 16 immunomodulatory (IM), 12 mesenchymal, 6 androgen receptor-like and 1 mesenchymal stem-like. Mean follow-up time was 47.1 months. The IM molecular subtype had the best overall survival (OS) (median OS was not reached). BSL2 had the worst OS (15 months). A complete pathologic response to neoadjuvant chemotherapy was obtained more often in the IM subtype (P=0.032). No significant associations were found between any of the clinical or pathological characteristics and the TNBC molecular subtypes. The results obtained from the present study should be considered when seeking to implement a clinical-molecular model for TNBC patient care, particularly in Hispanic-based populations, as they have been frequently underrepresented in clinical studies assessing TNBC molecular subtypes.

Predictive value of PD-L1 expression to the efficacy of immune checkpoint inhibitors in advanced triple-negative breast cancer: A systematic review and meta-analysis

Background: Immune checkpoint inhibitors (ICIs) have been an emerging treatment strategy for advanced triple-negative breast cancer (TNBC). Some studies have shown that high expression of programmed death-ligand 1 (PD-L1) can achieve a better response of clinical efficacy. However, the efficacy of ICIs in advanced TNBC remains controversial. In this meta-analysis, we evaluated the correlation of PD-L1 expression with the efficacy of ICIs in patients with advanced TNBC. Methods: We conducted a systematic search using four databases until March 2022 to obtain eligible randomized controlled trials (RCTs). The quality of the studies was assessed by the Cochrane risk of bias tool. Hazard ratio (HR) was extracted to evaluate the relationship between PD-L1 expression and progression-free survival (PFS) or overall survival (OS) in patients with advanced TNBC. Results: Five randomized controlled clinical trials (RCTs) with 3104 patients were included in this meta-analysis. The results demonstrated that ICIs could significantly improve the OS (HR 0.77, 95% CI 0.60-0.98, p = 0.03) in PD-L1 positive TNBC group. In the subgroup analysis, longer OS was observed (HR: 0.70, 95% CI: 0.60-0.82, p = 0.00001) in PD-L1 positive TNBC patients receiving ICIs alone or ICIs combined with nab-paclitaxel. In terms of PFS, PFS was significantly improved (HR: 0.68, 95% CI: 0.58-0.79, p < 0.00001) in PD-L1 positive patients receiving first-line ICIs and chemotherapy compared to those with ICIs alone. No significant improvement was observed for OS or PFS in PD-L1 negative group. Conclusion: Our study indicated significant improvement for OS in advanced TNBC with ICIs therapy in the PD-L1 positive status, and ICIs alone or ICIs combined with nab-paclitaxel might be a excellent choice in terms of OS. Although PFS has no significant benefit in PD-L1 positive patients, the subgroup analysis showed that ICIs combined with chemotherapy could achieve the PFS benefit in the first-line treatment. However, further clinical studies are needed to validate our conclusions due to limited relevant research.

Targeting TRAIL Death Receptors in Triple-Negative Breast Cancers: Challenges and Strategies for Cancer Therapy

The tumor necrosis factor (TNF) superfamily member TNF-related apoptosis-inducing ligand (TRAIL) induces apoptosis in cancer cells via death receptor (DR) activation with little toxicity to normal cells or tissues. The selectivity for activating apoptosis in cancer cells confers an ideal therapeutic characteristic to TRAIL, which has led to the development and clinical testing of many DR agonists. However, TRAIL/DR targeting therapies have been widely ineffective in clinical trials of various malignancies for reasons that remain poorly understood. Triple negative breast cancer (TNBC) has the worst prognosis among breast cancers. Targeting the TRAIL DR pathway has shown notable efficacy in a subset of TNBC in preclinical models but again has not shown appreciable activity in clinical trials. In this review, we will discuss the signaling components and mechanisms governing TRAIL pathway activation and clinical trial findings discussed with a focus on TNBC. Challenges and potential solutions for using DR agonists in the clinic are also discussed, including consideration of the pharmacokinetic and pharmacodynamic properties of DR agonists, patient selection by predictive biomarkers, and potential combination therapies. Moreover, recent findings on the impact of TRAIL treatment on the immune response, as well as novel strategies to address those challenges, are discussed.

Multifunctional Au Modified Ti3C2-MXene for Photothermal/Enzyme Dynamic/Immune Synergistic Therapy

Ti₃C₂-MXene-based composites provide multifunctional interfaces in diagnosis and treatment of tumors. Herein, we proposed a multifunctional nanoplatform based on Ti₃C₂-MXene-Au nanocomposites, which combines photothermal properties and peroxidase-like activity, accomplishing synergistic photothermal therapy (PTT) and enzyme dynamic therapy (EDT) accompanied by photoacoustic (PA) and thermal dual-mode imaging in vivo. Furthermore, PTT induces immunogenic cell death, and EDT promotes cell apoptosis, facilitating dendritic cell (DC) maturation and T cell infiltration into the tumor. On this basis, the antibody OX40 (αOX40) was utilized to further contribute immune therapy for reversing the immunosuppressive tumor microenvironment by activating CD4⁺ and CD8⁺ T cells. In summary, a triune of PTT/EDT/antitumor immune therapy is achieved by combining Ti₃C₂-MXene-Au nanocomposites and αOX40, which possesses several strong features of good biocompatibility, NIR-controlled targeting, significant cancer cell killing, and satisfactory biosafety in vitro and in vivo. Our work might highlight the promising application of MXene-based nanoplatforms for cancer therapy.

Crosstalk between Immune Checkpoint Modulators, Metabolic Reprogramming and Cellular Plasticity in Triple-Negative Breast Cancer

Breast cancer is one of the major causes of mortality in women worldwide. Accounting for 15-20% of all breast cancer diagnoses, the triple-negative breast cancer (TNBC) subtype presents with an aggressive clinical course, heightened metastatic potential and the poorest short-term prognosis. TNBC does not respond to hormonal therapy, only partially responds to radio- and chemotherapy, and has limited targeted therapy options, thus underlining the critical need for better therapeutic treatments. Although immunotherapy based on immune checkpoint inhibition is emerging as a promising treatment option for TNBC patients, activation of cellular plasticity programs such as metabolic reprogramming (MR) and epithelial-to-mesenchymal transition (EMT) causes immunotherapy to fail. In this report, we review the role of MR and EMT in immune checkpoint dysregulation in TNBCs and specifically shed light on development of novel combination treatment modalities for this challenging disease. We highlight the clinical relevance of crosstalk between MR, EMT, and immune checkpoints in TNBCs.

Triple negative breast cancer (TNBC): Non-genetic tumor heterogeneity and immune microenvironment: Emerging treatment options

Triple-negative breast cancer (TNBC) is an aggressive subtype characterized by extensive intra-tumoral heterogeneity, and frequently develops resistance to therapies. Tumor heterogeneity and lack of biomarkers are thought to be some of the most difficult challenges driving therapeutic resistance and relapse. This review will summarize current therapy for TNBC, studies in treatment resistance and relapse, including data from recent single cell sequencing. We will discuss changes in both the transcriptome and epigenome of TNBC, and we will review mechanisms regulating the immune microenvironment. Lastly, we will provide new perspective in patient stratification, and treatment options targeting transcriptome dysregulation and the immune microenvironment of TNBC patients.

Safety analyses from the phase 3 ASCENT trial of sacituzumab govitecan in metastatic triple-negative breast cancer

Sacituzumab govitecan (SG) is an anti-Trop-2 antibody-drug conjugate with an SN-38 payload. In the ASCENT study, patients with metastatic triple-negative breast cancer (mTNBC) relapsed/refractory to ≥2 prior chemotherapy regimens (≥1 in the metastatic setting), received SG or single-agent treatment of physician's choice (eribulin, vinorelbine, capecitabine, or gemcitabine). This ASCENT safety analysis includes the impact of age and UGT1A1 polymorphisms, which hinder SN-38 detoxification. SG demonstrated a manageable safety profile in patients with mTNBC, including those ≥65 years; neutropenia/diarrhea are key adverse events (AE). Patients with UGT1A1 *28/*28 genotype versus those with 1/*28 and *1/*1 genotypes had higher rates of grade ≥3 SG-related neutropenia (59% vs 47% and 53%), febrile neutropenia (18% vs 5% and 3%), anemia (15% vs 6% and 4%), and diarrhea (15% vs 9% and 10%), respectively. Individuals with UGT1A1 *28/*28 genotype should be monitored closely; active monitoring and routine AE management allow optimal therapeutic exposure of SG.

In Vitro Evaluation of NLS-DTX Activity in Triple-Negative Breast Cancer

Cancer is one of the most lethal diseases in the world, and the development and improvement of treatments used in cancer therapies are extremely important for a better quality of life for patients. In view of the current problems in drug administration such as low solubility and adverse effects, the activity of a solid lipid nanoparticle containing docetaxel (SLN-DTX), a drug already used in conventional therapies, was evaluated in a cell line (MDA-MB-231) of one of the most aggressive types of breast cancer with the worst prognosis, triple-negative breast cancer. Viability tests indicated that SLN-DTX has a greater dependence on the treatment dose when compared to the free drug, which indicates a more controlled release of the drug, and both reduced viability by around 50% at a concentration of 1 µg/mL after 72 h. Transmission electron microscopy (TEM) and confocal and light microscopy analyses indicated that after treatment the cells enter a mitotic catastrophe, characteristic of antimitotic drugs that usually make cells progress to death or senescence. Cells treated with both DTX and SLN-DTX showed significant inhibition of mobility, 73.6% and 66.5% when treated with SLN-DTX and DTX, respectively, compared to the 11.4% of the control after 72 h, characteristics that are very relevant in tumor development and progression. SLN-DTX demonstrated its great potential as a nanocarrier by maintaining and improving the drug’s action in the MDA-MB-231 cell line.

Treatment for Triple-Negative Breast Cancer: An Umbrella Review of Meta-Analyses

Purpose

In recent years, many meta-analyses of triple-negative breast cancer (TNBC) treatment have been published; however, these studies still lack systematic summary. Therefore, the aim of this study is to summarize and evaluate the evidence level and efficacy of treatment for TNBC.

Materials and Methods

Retrospective and prospective studies on treatment of TNBC were searched in the PubMed, Embase, and Cochrane Library databases. The literature search deadline was June 30, 2021. Two investigators independently screened the literature and extracted the data. In addition, the joint World Health Organization–United Nations Food and Agriculture Organization expert consultation was used to evaluate the validity of the evidence.

Results

A total of 28 meta-analyses were included in this study. The treatment interventions for TNBC mainly included surgery, chemotherapy (CT), radiotherapy, molecular targeted therapy, immunotherapy, zoledronic acid, and gonadotropin-releasing hormone (GnRH) analog. Platinum improves the pathological complete response (PCR) rate of patients treated with neoadjuvant chemotherapy (NACT), the objective remission rate (ORR) and overall survival (OS) in patients with metastatic triple-negative breast cancer. Capecitabine improves disease-free survival (DFS) and OS in patients treated with adjuvant CT. Bevacizumab was added to NACT to improve the PCR rate in patients. Immunotherapy improves the PCR rate in patients treated with NACT. The improvement in PCR rate in patients with high Ki67 expression treated with neoadjuvant therapy is highly suggestive. Other interventions had suggestive or weak evidence.

Conclusion

Among the strategies for treating TNBC, platinum, bevacizumab, and immunotherapy can lead to better PCR rates as part of a NACT regimen. Capecitabine as adjuvant CT and platinum in the treatment of metastatic TNBC can benefit patients’ survival. However, the effectiveness of other interventions for TNBC is not yet clear. Further research is needed in the future to obtain more reliable clinical evidence.

A novel star-shaped trinuclear platinum(II) complex based on a 1,3,5-triazine core displaying potent antiproliferative activity against TNBC by the mitochondrial injury and DNA damage mechanism

Polynuclear platinum(II) complexes represent a class of great prospective Pt-based antitumor drugs that may expand the antitumor spectrum and overcome the clinical problems of drug resistance and side effects of platinum-based drugs. Herein, a novel star-shaped trinuclear platinum(II) complex [Pt₃(L-3H)Cl₃] (1, L = 2,4,6-tris[(2-hydroxybenzyl)(2-pyridylmethyl)amine]-1,3,5-triazine) and its monomer [Pt(L'-H)Cl] (2, L' = (2-hydroxybenzyl)(2-pyridylmethyl)amine) were synthesized and characterized. The in vitro antiproliferative activities of complexes 1 and 2 against a panel of human cancer cell lines including MDA-MB-231 (triple-negative breast cancer, TNBC), MCF-7 (breast), HepG-2 (liver), and A549 (lung) were investigated. The results revealed that 1 exhibited much higher antiproliferative properties than its monomer 2 against the tested cell lines. Importantly, 1 possessed 3.3-fold higher antiproliferative activity as compared with cisplatin against the TNBC cell line MDA-MB-231. Another TNBC cell line MDA-MB-468 is also sensitive to 1. The results indicated that 1 might have the potential to act as a candidate for the treatment of TNBC. Cellular uptake and distribution studies showed that 1 could pass through the membrane of cells and enter into cells and mainly accumulate in the nuclei and mitochondria. 1 could bind to DNA in a cooperative groove-electrostatic-platinating binding mode and induce stronger DNA double-strand breaks (DSBs) and damaging effects on MDA-MB-231 than cisplatin (upregulation of γ-H2AX). Moreover, the DNA damage could not be easily repaired (upregulation of p53), which would exert a much positive influence on the overcoming of drug resistance. Additionally, flow cytometry studies showed that 1 arrested the cell cycle in the G0/G1 phase, induced mitochondrial membrane depolarization, increased ROS generation, and induced cell apoptosis. The results demonstrated that 1 could target simultaneously mitochondria and nuclei that gave rise to mitochondrial injury and DNA damage and ultimately efficiently promote the apoptotic death of tumor cells. Further mechanistic studies showed that 1 induced MDA-MB-231 cell apoptosis via the p53-mediated mitochondrial pathway by upregulating Bax and cytochrome c and downregulating Bcl-2 proteins, leading to the activation of caspase-3 and upregulation of the cleaved-PARP level. Taken together, 1 with such a synergic mechanism has great potential to be an effective anticancer agent that can overcome treatment resistance in TNBC.

Adenosine Kinase on Deoxyribonucleic Acid Methylation: Adenosine Receptor-Independent Pathway in Cancer Therapy

Methylation is an important mechanism contributing to cancer pathology. Methylation of tumor suppressor genes and oncogenes has been closely associated with tumor occurrence and development. New insights regarding the potential role of the adenosine receptor-independent pathway in the epigenetic modulation of DNA methylation offer the possibility of new interventional strategies for cancer therapy. Targeting DNA methylation of cancer-related genes is a promising therapeutic strategy; drugs like 5-Aza-2′-deoxycytidine (5-AZA-CdR, decitabine) effectively reverse DNA methylation and cancer cell growth. However, current anti-methylation (or methylation modifiers) are associated with severe side effects; thus, there is an urgent need for safer and more specific inhibitors of DNA methylation (or DNA methylation modifiers). The adenosine signaling pathway is reported to be involved in cancer pathology and participates in the development of tumors by altering DNA methylation. Most recently, an adenosine metabolic clearance enzyme, adenosine kinase (ADK), has been shown to influence methylation on tumor suppressor genes and tumor development and progression. This review article focuses on recent updates on ADK and its two isoforms, and its actions in adenosine receptor-independent pathways, including methylation modification and epigenetic changes in cancer pathology.

Integration of radiogenomic features for early prediction of pathological complete response in patients with triple-negative breast cancer and identification of potential therapeutic targets

Background

We established a radiogenomic model to predict pathological complete response (pCR) in triple-negative breast cancer (TNBC) and explored the association between high-frequency mutations and drug resistance.

Methods

From April 2018 to September 2019, 112 patients who had received neoadjuvant chemotherapy were included. We randomly split the study population into training and validation sets (2:1 ratio). Contrast-enhanced magnetic resonance imaging scans were obtained at baseline and after two cycles of treatment and were used to extract quantitative radiomic features and to construct two radiomics-only models using a light gradient boosting machine. By incorporating the variant allele frequency features obtained from baseline core tissues, a radiogenomic model was constructed to predict pCR. Additionally, we explored the association between recurrent mutations and drug resistance.

Results

The two radiomics-only models showed similar performance with AUCs of 0.71 and 0.73 (p = 0.55). The radiogenomic model had a higher predictive ability than the radiomics-only model in the validation set (p = 0.04), with a corresponding AUC of 0.87 (0.73–0.91).

Two highly frequent mutations were selected after comparing the mutation sites of pCR and non-pCR populations. The MED23 mutation p.P394H caused epirubicin resistance in vitro (p < 0.01). The expression levels of γ-H2A.X, p-ATM and p-CHK2 in MED23 p.P394H cells were significantly lower than those in wild type cells (p < 0.01). In the HR repair system, the GFP positivity rate of MED23 p.P394H cells was higher than that in wild-type cells (p < 0.01).

Conclusions

The proposed radiogenomic model has the potential to accurately predict pCR in TNBC patients. Epirubicin resistance after MED23 p.P394H mutation might be affected by HR repair through regulation of the p-ATM-γ-H2A.X-p-CHK2 pathway.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-022-03452-1.

The European Medicines Agency review of sacituzumab govitecan for the treatment of triple-negative breast cancer

Sacituzumab govitecan (SG) is an antineoplastic agent which combines a humanized monoclonal antibody binding to trophoblast cell surface antigen-2 (Trop-2)-expressing cancer cells, linked with cytotoxic moiety SN-38 (govitecan) with topoisomerase I inhibitor action. On 22 November 2021, a marketing authorization valid through the European Union (EU) was issued under the European Medicines Agency (EMA)’s accelerated assessment program for SG as monotherapy for the treatment of adult patients with unresectable or metastatic triple-negative breast cancer (mTNBC) who have received two or more prior systemic therapies, including at least one of them for advanced disease. The assessment was based on results from an open-label, randomized, phase III trial to evaluate the safety, tolerability, pharmacokinetics and efficacy of SG versus treatment of physician’s choice (TPC) in patients with mTNBC who received at least two prior treatments including at least one of them for advanced disease. The efficacy results in the overall population, based on mature data, showed a statistically significant improvement of SG over TPC in progression-free survival (PFS) and overall survival (OS). The median PFS was 4.8 months versus 1.7 months [hazard ratio (HR) = 0.43, n = 529; 95% CI 0.35-0.54; P < 0.0001] and the median OS was 11.8 months versus 6.9 months (HR = 0.51, n = 529; 95% CI 0.41-0.62; P < 0.0001). The most common (>30%) side effects of SG were diarrhea, neutropenia, nausea, fatigue, alopecia, anemia, constipation and vomiting. The aim of this manuscript is to summarize the scientific review of the application leading to regulatory approval in the EU.

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Trodelvy (SG) received a marketing authorization valid throughout the EU on 22 November 2021.

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SG is indicated for adults with unresectable or metastatic TBNC.

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SG is an antibody–drug conjugate considered a first-in-class medicine.

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SG prolonged OS and PFS ∼5 and 3 months, respectively, when compared to TPC.

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The most common serious side effects are febrile neutropenia and diarrhea.

Anticancer mechanism of 7-α-hydroxyfrullanolide on microtubules and computational prediction of its target binding in triple-negative breast cancer cells

Background

Triple-negative breast cancer (TNBC) responds poorly to the available drugs; thus, the mortality rate associated with TNBC remains high. 7-α-Hydroxyfrullanolide (7HF) possesses anticancer properties and arrests cells in the G2/M-phase via modulation of several proteins involved in the G2/M-phase transition, as well as the mitotic checkpoint in MDA-MB-468 (TNBC) cells. Microtubules (MTs) dynamically regulate cell division in the G2/M phase and are related to cancer cell stress response. However, antimitotic drug cytotoxicity to multiple cancer resistance developed in response to drugs are obstacles faced to date. Here, the activity and mechanism via which 7HF controls MTs dynamics was investigated in MDA-MB-468 cells.

Methods

7HF uptake by MDA-MB-468 cells was assessed using spectrophotometry. The drug-like properties of 7HF were predicted using the Swiss-absorption, distribution, metabolism, and excretion (ADME) webtool. Then, the effect of 7HF treatment (6, 12, and 24 µM) on the dynamic arrangement of MTs was assessed for 1, 12, and 24 h using indirect immunofluorescence. Polymerization of α- and β-tubulin was assessed using different 7HF concentrations in a cell-free system for 1 h. Cell proliferation assay with bromodeoxyuridine plus propidium iodide staining and flow cytometry was performed at different 7HF concentrations and time points. The mechanism of action was assessed by detecting the expression of proteins, including Bub3, cyclin B1, p-Cdk1 (Tyr15), Rb, p-Rb (Ser780), Chk1, p-Chk1 (Ser345), Chk2, p-Chk2 (Ser516), and p-H2AX (Ser139), using western blotting. Molecular docking was used to predict the molecular interactions between 7HF and tubulins in MTs.

Results

We observed that 7HF was able to enter the MDA-MB-468 cells. The ADME webtool analysis predicted that it possesses the high passive permeation and gastrointestinal absorption properties of drugs. Various concentrations of 7HF disrupted the dynamic arrangement of spindle MTs by causing radial spindle array shrinkage and expansion of fibrous spindle density and radial array lengths in a time-dependent manner. 7HF reduced polymerization of α-, β-tubulin in dose-dependent manner. 7HF also triggered DNA damage response by inducing G2/M and G1 phase arrests in a concentration and time-dependent manner, which occurred due to the upregulation of Bub3, Chk1, p-Chk1 (Ser345), p-Cdk1 (Tyr15), and cyclin B1. According to molecular docking analysis, 7HF preferred to bind to β-tubulin over α-tubulin. The lactone, ketone, and hydroxyl groups of 7HF supported the 7HF-tubulin interactions. Hydrogen bonding with a hydrocarbon ring and salt bridge attractive forces were responsible for the binding versatility of 7HF.

Conclusions

This is the first study to investigate the molecular mechanism, MTs interacting sites, and the internalization and drug-like properties of 7HF in TNBC cells. The findings will be useful for developing 7HF-based treatment for patients with TNBC.

Interruptin C, a Radioprotective Agent, Derived from Cyclosorus terminans Protect Normal Breast MCF-10A and Human Keratinocyte HaCaT Cells against Radiation-Induced Damage

Radiotherapy is a common method to treat cancers, with the goal of maximizing the dose to tumors while minimizing the dose to normal tissues. Radioprotectors can reduce the toxicity to normal tissues during radiotherapy. Several plant-derived compounds can function as radioprotectors by scavenging free radicals. We investigated the radioprotective activity of interruptin C from the fern Cyclosorus terminans. The molecular mechanism of interruptin C’s activity in X-ray-irradiated cells was evaluated. Superoxide dismutase activity was examined to investigate the antioxidant enzyme activity. Clonogenic cell survival was also investigated following radiation exposure. DNA damage and cell cycle progression were detected using micronuclei formation assays. DNA repair after irradiation was analyzed in a γH2AX assay. The levels of the proteins related to the radioprotective responses were analyzed by Western blotting. Interruptin C increased the antioxidant enzyme activity and significantly decreased the DNA damage by reducing the γH2AX foci and micronucleus formation in irradiated MCF-10A normal breast and HaCaT human keratinocyte cells. The apoptotic protein levels decreased, whereas the antiapoptotic protein levels increased. Interruptin C pretreatment increased the survival rate of irradiated MCF-10A and HaCaT cells. Moreover, the compound did not promote the survival of MDA-MB-231 and Hs578T breast cancer cells. Therefore, interruptin C may exert radioprotective activity without enhancing cancer cell proliferation.