Triple-negative breast cancer: current perspective on the evolving therapeutic landscape

A review on tyrosine kinase inhibitors for targeted breast cancer therapy

Breast cancer is a heterogeneous disease with complex molecular pathogenesis. Overexpression of several tyrosine kinase receptors is associated with poor prognosis, therefore, they can be key targets in breast cancer therapy. Tyrosine kinase inhibitors (TKIs) have emerged as leading agents in targeted cancer therapy due to their effectiveness in disrupting key molecular pathways involved in tumor growth. TKIs target various tyrosine kinases, including the human epidermal growth factor receptor 2 (HER2), epidermal growth factor receptor (EGFR), Vascular endothelial growth factor receptor (VEGFR), anaplastic lymphoma kinase (ALK), vascular endothelial growth factor receptor (VEGFR)-associated multi-targets, rearranged during transfection (RET), fibroblast growth factor receptor (FGFR), receptor tyrosine kinase-like orphan signal 1 (ROS1), Mitogen-activated protein kinase (MAPK), and tropomyosin receptor kinase (TRK). These drugs target the tyrosine kinase domain of receptor tyrosine kinases and play a vital role in proliferation and migration of breast cancer cells. Several TKIs, including lapatinib, neratinib, and tucatinib, have been developed and are currently used in clinical settings, often in combination with chemotherapy, endocrine therapy, or other targeted agents. TKIs have demonstrated remarkable benefits in enhancing progression-free and overall survival in patients with breast cancer and have become a standard of care for this population. This review provides an overview of TKIs currently being examined in preclinical studies and clinical trials, especially in combination with drugs approved for breast cancer treatment. TKIs have emerged as a promising therapeutic option for patients with breast cancer and hold potential for treating other breast cancer subtypes. The development of new TKIs and their integration into personalized treatment strategies will continue to shape the future of breast cancer therapy.

Mesothelin- and nucleolin-specific T cells from combined short peptides effectively kill triple-negative breast cancer cells

BACKGROUND

Triple-negative breast cancer (TNBC), known for its aggressiveness and limited treatment options, presents a significant challenge. Adoptive cell transfer, involving the ex vivo generation of antigen-specific T cells from peripheral blood mononuclear cells (PBMCs), emerges as a promising approach. The overexpression of mesothelin (MSLN) and nucleolin (NCL) in TNBC samples underscores their potential as targets for T cell therapy. This study explored the efficacy of multi-peptide pulsing of PBMCs to generate MSLN/NCL-specific T cells targeting MSLN+/NCL+ TNBC cells.

METHODS

TNBC patient samples were confirmed for both MSLN and NCL expression via immunohistochemistry. Synthesized MSLN and NCL peptides were combined and administered to activate PBMCs from healthy donors. The cancer-killing ability of the resultant T cells was assessed using crystal violet staining, and their subtypes and cytotoxic cytokines were characterized through flow cytometry and cytokine bead array.

RESULTS

Findings showed that 85.3% (127/149) of TNBC cases were positive for either MSLN or NCL, or both; with single positivity rates for MSLN and NCL of 14.1% and 28.9%, respectively. MSLN and NCL peptides, with high binding affinity for HLA-A*02, were combined and introduced to activated PBMCs from healthy donors. The co-pulsed PBMCs significantly induced TEM and TEMRA CD3+/CD8+ T cells and IFN-γ production, compared to single-peptide pulsed or unpulsed conditions. Notably, MSLN/NCL-specific T cells successfully induced cell death in MSLN+/NCL+ MDA-MB-231 cells, releasing key cytotoxic factors such as perforin, granzymes A and B, Fas ligand, IFN-γ, and granulysin.

CONCLUSIONS

These findings serve as a proof-of-concept for using multiple immunogenic peptides as a novel therapeutic approach in TNBC patients.

Digital Whole Slide Image Analysis of Elevated Stromal Content and Extracellular Matrix Protein Expression Predicts Adverse Prognosis in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a subtype of breast cancer with a poor prognosis and limited treatment options. This study evaluates the prognostic value of stromal markers in TNBC, focusing on the tumor-stroma ratio (TSR) and overall stroma ratio (OSR) in whole slide images (WSI), as well as the expression of type-I collagen, type-III collagen, and fibrillin-1 on tissue microarrays (TMAs), using both visual assessment and digital image analysis (DIA). A total of 101 female TNBC patients, primarily treated with surgery between 2005 and 2016, were included. We found that high visual OSR correlates with worse overall survival (OS), advanced pN categories, lower stromal tumor-infiltrating lymphocyte count (sTIL), lower mitotic index, and patient age (p < 0.05). TSR showed significant connections to the pN category and mitotic index (p < 0.01). High expression levels of type-I collagen (>45%), type-III collagen (>30%), and fibrillin-1 (>20%) were linked to significantly worse OS (p = 0.004, p = 0.013, and p = 0.005, respectively) and progression-free survival (PFS) (p = 0.028, p = 0.025, and p = 0.002, respectively), validated at the mRNA level. Our results highlight the importance of stromal characteristics in promoting tumor progression and metastasis and that targeting extracellular matrix (ECM) components may offer novel therapeutic strategies. Furthermore, DIA can be more accurate and objective in evaluating TSR, OSR, and immunodetected stromal markers than traditional visual examination.

Ivermectin Synergizes with Modulated Electro-hyperthermia and Improves Its Anticancer Effects in a Triple-Negative Breast Cancer Mouse Model

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype, with limited treatment options. Modulated electro-hyperthermia (mEHT) is a novel adjuvant cancer therapy that induces selective cancer damage. However, mEHT upregulates heat shock protein beta 1 (HSPB1), a cancer-promoting stress chaperone molecule. Thus, we investigated whether ivermectin (IVM), an anthelmintic drug, may synergize with mEHT and enhance its anticancer effects by inhibiting HSPB1 phosphorylation. Isogenic 4T1 TNBC cells were inoculated into BALB/c mice and treated with mEHT, IVM, or a combination of both. IVM synergistically improved the tumor growth inhibition achieved by mEHT. Moreover, IVM downregulated mEHT-induced HSPB1 phosphorylation. Thus, the strongest cancer tissue damage was observed in the mEHT + IVM-treated tumors, coupled with the strongest apoptosis induction and proliferation inhibition. In addition, there was no significant body weight loss in mice treated with mEHT and IVM, indicating that this combination was well-tolerated. In conclusion, mEHT combined with IVM is a new, effective, and safe option for the treatment of TNBC.

Prognostic and Therapeutic Implications of Cell Division Cycle 20 Homolog in Breast Cancer

Cell division cycle 20 homolog (CDC20) is a well-known regulator of cell cycle progression. Abnormal expression of CDC20 leads to mitotic defects, which play a significant role in cancer development. In breast cancer (BC), CDC20 has been identified as a biomarker that has been linked to poor patient outcomes. In this study, we investigated the association of CDC20 with BC prognosis and immune cell infiltration by using multiple online databases, including UALCAN, KM plotter, TIMER2.0, HPA, TNM-plot, bc-GenExMiner, LinkedOmics, STRING, and GEPIA. The results demonstrate that BC patients have an elevated CDC20 expression in tumor tissues compared with the adjacent normal tissue. In addition, BC patients with overexpressed CDC20 had a median survival of 63.6 months compared to 169.2 months in patients with low CDC20 expression. Prognostic analysis of the examined data indicated that elevated expression of CDC20 was associated with poor prognosis and a reduction of overall survival in BC patients. These findings were even more prevalent in chemoresistance triple-negative breast cancer (TNBC) patients. Furthermore, the Gene Set Enrichment Analysis tool indicated that CDC20 regulates BC cells' cell cycle and apoptosis. CDC20 also significantly correlates with increased infiltrating B cells, CD4+ T cells, neutrophils, and dendritic cells in BC. In conclusion, the findings of this study suggest that CDC20 may be involved in immunomodulating the tumor microenvironment and provide evidence that CDC20 inhibition may serve as a potential therapeutic approach for the treatment of BC patients. In addition, the data indicates that CDC20 can be a reliable prognostic biomarker for BC.

"Three-in-one": A Photoactivable Nanoplatform Evokes Anti-Immune Response by Inhibiting BRD4-cMYC-PDL1 Axis to Intensify Photo-Immunotherapy

Combinatorial immuno-cancer therapy is recognized as a promising approach for efficiently treating malignant tumors. Yet, the development of multifunctional nanomedicine capable of precise tumor targeting, remote activation, and immune-regulating drug delivery remains a significant challenge. In this study, nanoparticles loaded with an immune checkpoint inhibitor (JQ-1) using polypyrrole/hyaluronic acid (PPyHA/JQ-1) are developed. These nanoparticles offer active tumor targeting, photothermal tumor ablation using near-infrared light, and laser-controlled JQ-1 release for efficient breast cancer treatment. When the molecular weight of HA varies (from 6.8 kDa to 3 MDa) in the PPyHA nanoparticles, it is found that the nanoparticles synthesized using 1 MDa HA, referred to as PPyHA (1 m), show the most suitable properties, including small hydrodynamic size, high surface HA contents, and colloidal stability. Upon 808 nm laser irradiation, PPyHA/JQ-1 elevates the temperature above 55 °C, which is sufficient for thermal ablation and active release of JQ-1 in the tumor microenvironment (TME). Notably, the controlled release of JQ-1 substantially inhibits the expression of cancer-promoting genes. Furthermore, PPyHA/JQ-1 effectively suppresses the expression of programmed cell death ligand 1 (PD-L1) and prolongs dendritic cell maturation and CD8+ T cell activation against the tumor both in vitro and in vivo. PPyHA/JQ-1 treatment simultaneously provides a significant tumor regression through photothermal therapy and immune checkpoint blockade, leading to a durable antitumor-immune response. Overall, "Three-in-one" immunotherapeutic photo-activable nanoparticles have the potential to be beneficial for a targeted combinatorial treatment approach for TNBC.

Enhancing breast cancer treatment: Comprehensive study of gefitinib-loaded poloxamer 407/TPGS mixed micelles through design, development, in-silico modelling, In-Vitro testing, and Ex-Vivo characterization

Breast cancer continues to pose a substantial global health challenge, emphasizing the critical need for the advancement of novel therapeutic approaches. Key players in the regulation of apoptosis, a fundamental process in cell death, are the B-cell lymphoma 2 (Bcl-2) family proteins, namely Bcl-2 and Bax. These proteins have garnered attention as highly promising targets for the treatment of breast cancer. Targeting the overexpressed anti-apoptotic Bcl-2 protein in breast cancer, Gefitinib (GEF), an EGFR (Epidermal Growth Factor Receptor) inhibitor, emerges as a potential solution. This study focuses on designing Gefitinib-loaded polymeric mixed micelles (GPMM) using poloxamer 407 and TPGS (D-alpha tocopherol PEG1000 succinate) for breast cancer therapy. In silico analyses unveil strong interactions between GEF- Bcl-2 and TPGS-Pgp-2 receptors, indicating efficacy against breast cancer. Molecular dynamics simulations offer insights into GEF and TPGS interactions within the micelles. Formulation optimization via Design of Experiment ensures particle size and entrapment efficiency within acceptable ranges. Characterization tools such as zeta sizer, ATR-FTIR, XRD, TEM, AFM, NMR, TGA, and DSC confirms particle size, structure, functional groups, and thermodynamic events. The optimized micelles exhibit a particle size of 22.34 ± 0.18 nm, PDI of 0.038 ± 0.009, and zeta potential of -0.772 ± 0.12 mV. HPLC determines 95.67 ± 0.34% entrapment efficiency and 1.05 ± 0.12% drug loading capacity. In-vitro studies with MDA-MB-231 cell lines demonstrate enhanced cytotoxicity of GPMM compared to free GEF, suggesting its potential in breast cancer therapy. Cell cycle analysis reveals apoptosis induction through key apoptotic proteins. Western blot results confirm GPMM's ability to trigger apoptosis in MDA-MB-231 cells by activating caspase-3, Bax, Bcl-2, and Parp. In conclusion, these polymeric mixed micelles show promise in selectively targeting cancer cells, warranting future in-vivo studies for optimized clinical application against breast cancer.

The role of UBR5 in tumor proliferation and oncotherapy

Ubiquitin (Ub) protein ligase E3 component n-recognin 5 (UBR5), as a crucial Ub ligase, plays a pivotal role in the field of cell biology, attracting significant attention for its functions in regulating protein degradation and signaling pathways. This review delves into the fundamental characteristics and structure of UBR5. UBR5, through ubiquitination, regulates various key proteins, directly or indirectly participating in cell cycle control, thereby exerting a direct impact on the proliferation of tumor cells. Meanwhile, we comprehensively review the expression levels of UBR5 in different types of tumors and its relationship with tumor development, providing key clues for the role of UBR5 in cancer. Furthermore, we summarize the current research status of UBR5 in cancer treatment. Through literature review, we find that UBR5 may play a crucial role in the sensitivity of tumor cells to radiotherapy chemotherapy, and other anti-tumor treatment, providing new insights for optimizing cancer treatment strategies. Finally, we discuss the challenges faced by UBR5 in cancer treatment, and looks forward to the future research directions. With the continuous breakthroughs in technology and in-depth research, we hope to further study the biological functions of UBR5 and lay the foundation for its anti-tumor treatment.

Cellular Responses Induced by NCT-503 Treatment on Triple-Negative Breast Cancer Cell Lines: A Proteomics Approach

Breast cancer (BC) remains one of the leading causes of mortality among women, with triple-negative breast cancer (TNBC) standing out for its aggressive nature and limited treatment options. Metabolic reprogramming, one of cancer's hallmarks, underscores the importance of targeting metabolic vulnerabilities for therapeutic intervention. This study aimed to investigate the impact of de novo serine biosynthetic pathway (SSP) inhibition, specifically targeting phosphoglycerate dehydrogenase (PHGDH) with NCT-503, on three TNBC cell lines: MDA-MB-231, MDA-MB-468 and Hs 578T. First, MS-based proteomics was used to confirm the distinct expression of PHGDH and other SSP enzymes using the intracellular proteome profiles of untreated cells. Furthermore, to characterize the response of the TNBC cell lines to the inhibitor, both in vitro assays and label-free, bottom-up proteomics were employed. NCT-503 exhibited significant cytotoxic effects on all three cell lines, with MDA-MB-468 being the most susceptible (IC50 20.2 ± 2.8 µM), while MDA-MB-231 and Hs 578T showed higher, comparable IC50s. Notably, differentially expressed proteins (DEPs) induced by NCT-503 treatment were mostly cell line-specific, both in terms of the intracellular and secreted proteins. Through overrepresentation and Reactome GSEA analysis, modifications of the intracellular proteins associated with cell cycle pathways were observed in the MDA-MBs following treatment. Distinctive dysregulation of signaling pathways were seen in all TNBC cell lines, while modifications of proteins associated with the extracellular matrix organization characterizing both MDA-MB-231 and Hs 578T cell lines were highlighted through the treatment-induced modifications of the secreted proteins. Lastly, an analysis was conducted on the DEPs that exhibited greater abundance in the NCT-503 treatment groups to evaluate the potential chemo-sensitizing properties of NCT-503 and the druggability of these promising targets.

Optimized Design of Hyaluronic Acid-Lipid Conjugate Biomaterial for Augmenting CD44 Recognition of Surface-Engineered NK Cells

Triple-negative breast cancer (TNBC) presents treatment challenges due to a lack of detectable surface receptors. Natural killer (NK) cell-based adaptive immunotherapy is a promising treatment because of the characteristic anticancer effects of killing malignant cells directly by secreting cytokines and lytic granules. To maximize the cancer recognition ability of NK cells, biomaterial-mediated ex vivo cell surface engineering has been developed for sufficient cell membrane immobilization of tumor-targeting ligands via hydrophobic anchoring. In this study, we optimized amphiphilic balances of NK cell coating materials composed of CD44-targeting hyaluronic acid (HA)-poly(ethylene glycol) (PEG)-lipid to improve TNBC recognition and the anticancer effect. Changes in the modular design of our material by differentiating hydrophilic PEG length and incorporating lipid amount into HA backbones precisely regulated the amphiphilic nature of HA-PEG-lipid conjugates. The optimized biomaterial demonstrated improved anchoring into NK cell membranes and facilitating the surface presentation level of HA onto NK cell surfaces. This led to enhanced cancer targeting via increasing the formation of immune synapse, thereby augmenting the anticancer capability of NK cells specifically toward CD44-positive TNBC cells. Our approach addresses targeting ability of NK cell to solid tumors with a deficiency of surface tumor-specific antigens while offering a valuable material design strategy using amphiphilic balance in immune cell surface engineering techniques.

NOX4 alleviates breast cancer cell aggressiveness by co-ordinating mitochondrial turnover through PGC1α/Drp1 axis

Triple Negative Breast Cancer (TNBC) is a highly aggressive form of breast cancer, with few treatment options. This study investigates the complex molecular mechanism by which NADPH oxidase 4 (NOX4), a major ROS producer in mitochondria, affects the aggressiveness of luminal and triple-negative breast cancer cells (TNBCs). We found that NOX4 expression was differentially regulated in luminal and TNBC cells, with a positive correlation to their epithelial characteristics. Time dependent analysis revealed that TNBCs exhibits higher steady-state ROS levels than luminal cells, but NOX4 silencing increased ROS levels in luminal breast cancer cells and enhanced their ability to migrate and invade. In contrast, NOX4 over expression in TNBCs had the opposite effect. The mouse tail-vein experiment showed that the group injected with NOX4 silenced luminal cells had a higher number of lung metastases compared to the control group. Mechanistically, NOX4 enhanced PGC1α dependent mitochondrial biogenesis and attenuated Drp1-mediated mitochondrial fission in luminal breast cancer cells, leading to an increased mitochondrial mass and elongated mitochondrial morphology. Interestingly, NOX4 silencing increased mitochondrial ROS (mtROS) levels without affecting mitochondrial (Δψm) and cellular integrity. Inhibition of Drp1-dependent fission with Mdivi1 reversed the effect of NOX4-dependent mitochondrial biogenesis, dynamics, and migration of breast cancer cells. Our findings suggest that NOX4 expression diminishes from luminal to a triple negative state, accompanied by elevated ROS levels, which may modulate mitochondrial turnover to attain an aggressive phenotype. The study provides potential insights for targeted therapies for TNBCs.

Stimulating T cell responses against patient-derived breast cancer cells with neoantigen peptide-loaded peripheral blood mononuclear cells

Breast cancer stands as a formidable global health challenge for women. While neoantigens exhibit efficacy in activating T cells specific to cancer and instigating anti-tumor immune responses, the accuracy of neoantigen prediction remains suboptimal. In this study, we identified neoantigens from the patient-derived breast cancer cells, PC-B-142CA and PC-B-148CA cells, utilizing whole-genome and RNA sequencing. The pVAC-Seq pipeline was employed, with minor modification incorporating criteria (1) binding affinity of mutant (MT) peptide with HLA (IC50 MT) ≤ 500 nm in 3 of 5 algorithms and (2) IC50 wild type (WT)/MT > 1. Sequencing results unveiled 2513 and 3490 somatic mutations, and 646 and 652 non-synonymous mutations in PC-B-142CA and PC-B-148CA, respectively. We selected the top 3 neoantigens to perform molecular dynamic simulation and synthesized 9-12 amino acid neoantigen peptides, which were then pulsed onto healthy donor peripheral blood mononuclear cells (PBMCs). Results demonstrated that T cells activated by ADGRL1E274K, PARP1E619K, and SEC14L2R43Q peptides identified from PC-B-142CA exhibited significantly increased production of interferon-gamma (IFN-γ), while PARP1E619K and SEC14L2R43Q peptides induced the expression of CD107a on T cells. The % tumor cell lysis was notably enhanced by T cells activated with MT peptides across all three healthy donors. Moreover, ALKBH6V83M and GAAI823T peptides from PC-B-148CA remarkably stimulated IFN-γ- and CD107a-positive T cells, displaying high cell-killing activity against target cancer cells. In summary, our findings underscore the successful identification of neoantigens with anti-tumor T cell functions and highlight the potential of personalized neoantigens as a promising avenue for breast cancer treatment.

Unveiling Epigenetic Vulnerabilities in Triple-Negative Breast Cancer through 3D Organoid Drug Screening

Triple-negative breast cancer (TNBC) poses a therapeutic challenge due to its aggressive nature and lack of targeted therapies. Epigenetic modifications contribute to TNBC tumorigenesis and drug resistance, offering potential therapeutic targets. Recent advancements in three-dimensional (3D) organoid cultures, enabling precise drug screening, hold immense promise for identifying novel compounds targeting TNBC. In this study, we established two patient-derived TNBC organoids and implemented a high-throughput drug screening system using these organoids and two TNBC cell lines. Screening a library of 169 epigenetic compounds, we found that organoid-based systems offer remarkable precision in drug response assessment compared to cell-based models. The top 30 compounds showing the highest drug sensitivity in the initial screening were further assessed in a secondary screen. Four compounds, panobinostat, pacritinib, TAK-901, and JIB-04, targeting histone deacetylase, JAK/STAT, histone demethylases, and aurora kinase pathways, respectively, exhibited potent anti-tumor activity in TNBC organoids, surpassing the effect of paclitaxel. Our study highlights the potential of these novel epigenetic drugs as effective therapeutic agents for TNBC and demonstrates the valuable role of patient-derived organoids in advancing drug discovery.

Integrated multiomic data analysis reveals the clinical significance of TXNIP and contributing to immune microenvironment in triple negative breast cancer

Triple negative breast cancer (TNBC) is a type of breast cancer with the worst clinical outcome. TNBC is not sensitive to typical endocrine therapy and targeted therapy. Thioredoxin interacting protein (TXNIP), known as a tumor suppressor, is related to oxidative stress and energy metabolism. However, the clinical significance of TXNIP in TNBC and mechanism in immunity have not been fully reported. In this study, we found that the expression of TXNIP was downregulated obviously in TNBC tissues and negatively correlated with tumor grade by comprehensive bioinformatics analysis and immunohistochemistry staining of 108 TNBC tissues. Through in vivo and in vitro experiments, we identified TXNIP as a tumor suppressor in TNBC. By bulk mRNA and scRNA analysis, we found that TXNIP could enhance immune response in TNBC and was a potential biomarker for cancer immunity and immunotherapy. We also performed the drug susceptibility analysis to reveal the therapeutic value of TXNIP. In conclusion, our findings demonstrated that TXNIP was a tumor suppressor in TNBC and was involved in tumor malignancy progression. TXNIP was a potential biomarker for immunotherapy and promising molecular therapeutic target.

Dose-dense neoadjuvant chemotherapy in triple-negative breast cancer: Real-world data from a developing country

BACKGROUND

Dose-dense adjuvant chemotherapy has been shown to be associated with improved long-term survival outcomes in triple-negative breast cancer (TNBC). However, there is a lacuna of data on the benefits of dose-dense neoadjuvant chemotherapy (NACT) in TNBC.

METHODS

This retrospective study included 217 newly diagnosed cases of TNBC treated with a sequential anthracycline and taxane-based NACT, followed by definitive surgery. Study groups consisted of 137 patients who received 3-weekly conventional chemotherapy (cNACT group) and 80 patients with 2-weekly dose-dense NACT (ddNACT group). Pathological complete response (pCR) rates, relapse-free survival (RFS), overall survival (OS), and grade-3/4 chemotoxicities were compared across the groups.

RESULTS

No significant difference in the pCR rate (32.8% versus 31.3%; P = 0.808) was observed across the study groups. Relapse rate was lower in the ddNACT group compared to the cNACT group (odds ratio [OR]: 0.51, 95% confidence interval [CI]: 0.27-0.95). However, ddNACT had no RFS advantage over conventional chemotherapy (median RFS: not reached versus 56.1 months in cNACT; hazard ratio: 0.90, 95% CI: 0.52-1.53). OS was also comparable in both the groups with a 3-year survival rate of 78.8% (95% CI: 60.9-89.2) in the ddNACT group versus 84.3% (95% CI: 74.8-90.4) in the cNACT group. Younger age, menopause, the Eastern Cooperative Oncology Group ECOG status, and pCR were significantly associated with OS in our cohort. Grade-3 toxicities were comparable in both groups.

CONCLUSIONS

This observational study focusing on ddNACT among TNBC patients demonstrated significant differences in the relapse rate with no survival benefits. Differential effects of ddNACT by tumor presentation (early vs. late), tumor size, tumor biology, and cost-benefits of granulocyte colony-stimulating factor support with such regimens need further exploration.

Cadherin-11 increases tumor cell proliferation and metastatic potential via Wnt pathway activation

During epithelial-mesenchymal transition (EMT) in cancer progression, tumor cells switch cadherin profile from E-cadherin to cadherin-11 (CDH11), which is accompanied by increased invasiveness and metastatic activity. However, the mechanism through which CDH11 may affect tumor growth and metastasis remains elusive. Here, we report that CDH11 was highly expressed in multiple human tumors and was localized on the membrane, in the cytoplasm and, surprisingly, also in the nucleus. Interestingly, β-catenin remained bound to carboxy-terminal fragments (CTFs) of CDH11, the products of CDH11 cleavage, and co-localized with CTFs in the nucleus in the majority of breast cancer samples. Binding of β-catenin to CTFs preserved β-catenin activity, whereas inhibiting CDH11 cleavage led to β-catenin phosphorylation and diminished Wnt signaling, similar to CDH11 knockout. Our data elucidate a previously unknown role of CDH11, which serves to stabilize β-catenin in the cytoplasm and facilitates its translocation to the nucleus, resulting in activation of Wnt signaling, with subsequent increased proliferation, migration and invasion potential.

A comprehensive overview on antibody-drug conjugates: from the conceptualization to cancer therapy

Antibody-Drug Conjugates (ADCs) represent an innovative class of potent anti-cancer compounds that are widely used in the treatment of hematologic malignancies and solid tumors. Unlike conventional chemotherapeutic drug-based therapies, that are mainly associated with modest specificity and therapeutic benefit, the three key components that form an ADC (a monoclonal antibody bound to a cytotoxic drug via a chemical linker moiety) achieve remarkable improvement in terms of targeted killing of cancer cells and, while sparing healthy tissues, a reduction in systemic side effects caused by off-tumor toxicity. Based on their beneficial mechanism of action, 15 ADCs have been approved to date by the market approval by the Food and Drug Administration (FDA), the European Medicines Agency (EMA) and/or other international governmental agencies for use in clinical oncology, and hundreds are undergoing evaluation in the preclinical and clinical phases. Here, our aim is to provide a comprehensive overview of the key features revolving around ADC therapeutic strategy including their structural and targeting properties, mechanism of action, the role of the tumor microenvironment and review the approved ADCs in clinical oncology, providing discussion regarding their toxicity profile, clinical manifestations and use in novel combination therapies. Finally, we briefly review ADCs in other pathological contexts and provide key information regarding ADC manufacturing and analytical characterization.

In-silico method for elucidation of prodigiosin as PARP-1 inhibitor a prime target of Triple-negative breast cancer

Triple-Negative Breast Cancer (TNBC) is found to be one of the life-threatening cancer. Poly (ADP-Ribose) Polymerase-1 (PARP-1) is overexpressed by those tumour cells, which become resistant to chemotherapies. Inhibition of PARP-1 has a considerable effect on treating TNBC. Prodigiosin is a valuable pharmaceutical compound that exhibits anticancer properties. The present study aims to virtually evaluate prodigiosin as a potent PARP-1 inhibitor using Molecular docking and Molecular Dynamics (MD) simulation studies. The PASS (Prediction of Activity Spectra for Substances) prediction tool evaluated the biological properties of prodigiosin. Then the drug-likeness and pharmacokinetic properties of prodigiosin were determined using Swiss-ADME software. It was suggested that prodigiosin obeyed Lipinski's rule of five and thus could act as a drug with good pharmacokinetic properties. Moreover, molecular docking was done with AutoDock 4.2 to identify the critical amino acids of the protein-ligand complex. It was indicated that prodigiosin has a docking score of -8.08 kcal/mol, which showed its effective interaction with crucial amino acid, His201A of PARP-1 protein. Further, MD simulation was performed using Gromacs software to validate the stability of the prodigiosin-PARP-1 complex. Prodigiosin was found to have good structural stability and affinity at the active site of PARP-1 protein. Additionally, PCA and MM-PBSA were calculated for the prodigiosin-PARP-1 complex, which revealed that prodigiosin has an excellent binding affinity towards PARP-1 protein. Prodigiosin can possibly be used as oral drug due to its PARP-1 inhibition through high binding affinity, structural stability, and receptor flexibility towards crucial amino acid residue His201A of PARP-1 protein. In-addition, in-vitro cytotoxicity, and apoptosis analysis of prodigiosin-treated TNBC cell line-MDA-MB-231 revealed that prodigiosin exhibited significant anticancer activity in 101.1 µg/mL concentration, when compared to commercially available synthetic drug cisplatin. Thus, prodigiosin could act as a potential candidate for treatment of TNBC than the commercially available synthetic drugs.

Novel Method to Obtain Contact Angles of Tumor Biopsies

Characterizing the strength of a solid-liquid interface can be done by depositing a single drop of liquid on a planar solid surface and measuring the angle of the formed semicircle, called the contact angle. The contact angle of pure water is indicative of a surface's hydrophobicity and is a useful metric in biomedical applications such as tissue scaffolding and drug/tissue interactions. However, the roughness and inhomogeneity of most biological surfaces make obtaining accurate contact angles of such materials challenging. Here, we developed an instrument and methodology to obtain contact angles of tissue sections. Breast cancer tumor and nearby healthy tissue sections were used as the model biological surface. The custom instrument was built on existing equipment by improving drop dispensing accuracy in the nanoliter range, an XYZ stage, additional side view cameras, and microscope-based sample visualization. The method takes into account the inherent surface inhomogeneity and topology of tissue and the required method of illumination for contact angle acquisition. As such, the system uses an inverted microscope with a high sensitivity camera, an XYZ stage for accurate droplet placement on tissue, and multiple cameras to obtain contact angles around the entire perimeter of the drop. We tested the system with breast cancer biopsies and adjacent normal tissue from 75 patients and report here a trend of tumor exhibiting higher water contact angles, and thus higher hydrophobicity, compared to their respective normal adjacent tissue. The system described here can be used to characterize any type of biological tissue, which can be sectioned, with any liquid including water or solutions with dissolved or suspended therapeutic molecules and particles.

CircKIF4A combines EIF4A3 to stabilize SDC1 expression to activate c-src/FAK and promotes TNBC progression

Triple-negative breast cancer (TNBC) is recognized for its poor prognosis and limited options for treatment. Circular RNA KIF4A (circKIF4A) was documented to be abnormally overexpressed in TNBC and was correlated with a poor survival rate. The objective of this study is to further examine the functional role of circKIF4A and its underlying mechanism. CircKIF4A was significantly upregulated in TNBC and the knockdown of circKIF4A suppressed TNBC cell proliferation, migration, and invasion. CircKIF4A was directly bound to EIF4A3, which interacted with SDC1. Knockdown of circKIF4A reduced interaction between EIF4A3 and SDC1 as well as SDC1 mRNA stability. SDC1 activated the c-src/FAK signaling pathways and finally promoted TNBC progression. circKIF4A induced TNBC progress in the in vivo mouse model via SDC1. CircKIF4A interacts with EIF4A3 to stabilize SDC1 mRNA, which activates the c-src/FAK signaling pathways and promotes TNBC progression. This may provide a potential therapy for TNBC treatment.

A Novel Dual-Payload ADC for the Treatment of HER2+ Breast and Colon Cancer

Antibody-drug conjugates (ADCs) have demonstrated a great therapeutic potential against cancer due to their target specificity and cytotoxicity. To exert a maximum therapeutic effect on cancerous cells, we have conjugated two different payloads to different amino acids, cysteines (cys) and lysines (lys), on trastuzumab, which is a humanised anti-HER2 monoclonal antibody. First, trastuzumab was conjugated with monomethyl auristatin E (MMAE), an antimitotic agent, through a cleavable linker (Val-Cit) to prepare ADC (Tmab-VcMMAE). Then, the ADC (Tmab-VcMMAE) was conjugated with a second antimitotic agent, Mertansine (DM1), via a non-cleavable linker Succinimidyl-4-(N-maleimidomethyl)cyclohexane-1-carboxylate (SMCC) to form a dual conjugate (Tmab-VcMMAE-SMCC-DM1). Our results indicated that the dual-payload conjugate, Tmab-VcMMAE-SMCC-DM1, had a synergistic and superior cytotoxic effect compared to trastuzumab alone. Ultimately employing a dual conjugation approach has the potential to overcome treatment-resistance and tumour recurrences and could pave the way to employ other payloads to construct dual (or multiple) payload complexes.

Advancements in clinical aspects of targeted therapy and immunotherapy in breast cancer

Breast cancer is the second leading cause of death for women worldwide. The heterogeneity of this disease presents a big challenge in its therapeutic management. However, recent advances in molecular biology and immunology enable to develop highly targeted therapies for many forms of breast cancer. The primary objective of targeted therapy is to inhibit a specific target/molecule that supports tumor progression. Ak strain transforming, cyclin-dependent kinases, poly (ADP-ribose) polymerase, and different growth factors have emerged as potential therapeutic targets for specific breast cancer subtypes. Many targeted drugs are currently undergoing clinical trials, and some have already received the FDA approval as monotherapy or in combination with other drugs for the treatment of different forms of breast cancer. However, the targeted drugs have yet to achieve therapeutic promise against triple-negative breast cancer (TNBC). In this aspect, immune therapy has come up as a promising therapeutic approach specifically for TNBC patients. Different immunotherapeutic modalities including immune-checkpoint blockade, vaccination, and adoptive cell transfer have been extensively studied in the clinical setting of breast cancer, especially in TNBC patients. The FDA has already approved some immune-checkpoint blockers in combination with chemotherapeutic drugs to treat TNBC and several trials are ongoing. This review provides an overview of clinical developments and recent advancements in targeted therapies and immunotherapies for breast cancer treatment. The successes, challenges, and prospects were critically discussed to portray their profound prospects.

Triple Negative Breast Cancer Treatment Options and Limitations: Future Outlook

Triple negative breast cancer (TNBC) has a negative expression of estrogen receptors (ER), progesterone receptors (PR), and human epidermal growth factor receptors (HER2). The survival rate for TNBC is generally worse than other breast cancer subtypes. TNBC treatment has made significant advances, but certain limitations remain. Treatment for TNBC can be challenging since the disease has various molecular subtypes. A variety of treatment options are available, such as chemotherapy, immunotherapy, radiotherapy, and surgery. Chemotherapy is the most common of these options. TNBC is generally treated with systemic chemotherapy using drugs such as anthracyclines and taxanes in neoadjuvant or adjuvant settings. Developing resistance to anticancer drugs and off-target toxicity are the primary hindrances to chemotherapeutic solutions for cancer. It is imperative that researchers, clinicians, and pharmaceutical companies work together to develop effective treatment options for TNBC. Several studies have suggested nanotechnology as a potential solution to the problem of suboptimal TNBC treatment. In this review, we summarized possible treatment options for TNBC, including chemotherapy, immunotherapy, targeted therapy, combination therapy, and nanoparticle-based therapy, and some solutions for the treatment of TNBC in the future. Moreover, we gave general information about TNBC in terms of its characteristics and aggressiveness.

A recombinant adenovirus vector containing the synNotch receptor gene for the treatment of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is known as the most difficult molecular subtype of breast cancer to treat. Recent studies revealed that cancer stem cells (CSCs) play a critical role in TNBC recurrence and metastasis. In this study, we developed a recombinant replication-deficient adenoviral vector (Ad-CD44-N-HIF-3α4), which contains a gene encoding a synthetic Notch (synNotch) receptor composed of the extracellular domain of CD44 (CD44-ECD) and the hypoxia-inducible factor (HIF)-3α4 connected by the Notch core regulatory region. CD44 is a transmembrane glycoprotein and known as a CSC marker in breast cancer and other malignancies. HIF-3α4 is a dominant-negative regulator of HIF-1α and HIF-2α and inhibits hypoxia-inducing effect. Both CD44 and HIF signals contribute cancer stemness and maintaining CSCs in breast cancer. The CD44-ECD in the synNotch receptor acts as the CD44 decoy receptor, and after a ligand such as a hyaluronic acid binds to the CD44-ECD, HIF-3α4 is released from the Notch core domain. We performed an in vivo study using a mouse xenograft model of MDA-MB-231, a highly invasive TNBC cell, and confirmed the significant antitumor activity of the intratumoral injections of Ad-CD44-N-HIF3α4. Our findings in this study warrant the further development of Ad-CD44-N-HIF3α4 for the treatment of patients with TNBC.

Dynamic tumor microenvironment, molecular heterogeneity, and distinct immunologic portrait of triple-negative breast cancer: an impact on classification and treatment approaches

Heterogeneity of the tumor microenvironment (TME) and the lack of a definite targetable receptor in triple-negative breast cancer (TNBC) has carved a niche for this cancer as a particularly therapeutically challenging form of breast cancer. However, recent advances in high-throughput genomic analysis have provided new insights into the unique microenvironment and defining characteristics of various subsets of TNBC. This improved understanding has contributed to the development of novel therapeutic strategies including targeted therapies such as PARP inhibitors and CDK inhibitors. Moreover, the recent FDA approval of the immune checkpoint inhibitor against programmed cell death protein 1 (PD-1), pembrolizumab and atezolizumab, holds the promise of improving the quality of life and increasing the overall survival of TNBC patients. This recent approval is one of the many therapeutically novel strategies that are currently being exploited in clinical trials toward eventual contribution to the oncologist's toolbox against TNBC. In this review, we comprehensively discuss TNBC's distinct TME and its immunophenotype. Furthermore, we highlight the histological and molecular classification of this cancer. More importantly, we describe how these characteristics and classifications contribute to the current standards of care and how they steer the development of newer and more targeted therapies toward achieving peak therapeutic goals in the treatment of TNBC.

Mammographic and ultrasonographic features of triple-negative breast cancer compared with non-triple-negative breast cancer

OBJECTIVE

To evaluate and compare the mammographic and ultrasonographic features of TNBC with non-TNBC.

METHODS

A retrospective review of 193 invasive breast cancer patients (TNBC = 32 and non-TNBC = 161) was collected from January 2014 to June 2019. The imaging features were reviewed according to the 5th edition of the American College of Radiology Breast Imaging Reporting and Data System lexicon. We used the student t-test, Mann-Whitney U test, and Fisher's exact test for statistical analyses.

RESULTS

Mass without calcifications was the most mammographic feature of TNBC (22 of 32, 68.8%) and more commonly found in TNBC than in non-TNBC (p = 0.007). The irregular shape (19 of 28, 67.9%) and indistinct margin (10 of 28, 35.7%) were the most common findings in the TNBC group. However, TNBC lesions appeared as round or oval shape and microlobulated margin more frequently than non-TNBC lesions (p < 0.001). Additionally, the tumor size and histological grade of TNBC were significantly higher than non-TNBC (p < 0.001).

CONCLUSION

TNBC has distinct imaging features compared to non-TNBC. The imaging features on mammography combined with ultrasonography can be used to detect and differentiate this subtype from other breast cancers.

Identifying biomarkers of differential chemotherapy response in TNBC patient-derived xenografts with a CTD/WGCNA approach

Although systemic chemotherapy remains the standard of care for TNBC, even combination chemotherapy is often ineffective. The identification of biomarkers for differential chemotherapy response would allow for the selection of responsive patients, thus maximizing efficacy and minimizing toxicities. Here, we leverage TNBC PDXs to identify biomarkers of response. To demonstrate their ability to function as a preclinical cohort, PDXs were characterized using DNA sequencing, transcriptomics, and proteomics to show consistency with clinical samples. We then developed a network-based approach (CTD/WGCNA) to identify biomarkers of response to carboplatin (MSI1, TMSB15A, ARHGDIB, GGT1, SV2A, SEC14L2, SERPINI1, ADAMTS20, DGKQ) and docetaxel (c, MAGED4, CERS1, ST8SIA2, KIF24, PARPBP). CTD/WGCNA multigene biomarkers are predictive in PDX datasets (RNAseq and Affymetrix) for both taxane- (docetaxel or paclitaxel) and platinum-based (carboplatin or cisplatin) response, thereby demonstrating cross-expression platform and cross-drug class robustness. These biomarkers were also predictive in clinical datasets, thus demonstrating translational potential.

Aquaporin water channels affect the response of conventional anticancer therapies of 3D grown breast cancer cells

Aquaporin (AQP) water channels facilitate water transport across cellular membranes and are essential in regulation of body water balance. Moreover, several AQPs are overexpressed or ectopically expressed in breast cancer. Interestingly, several in vitro studies have suggested that AQPs can affect the response to conventional anticancer chemotherapies. Therefore, we took a systematic approach to test how AQP1, AQP3 and AQP5, which are often over-/ectopically expressed in breast cancer, affect total viability of 3-dimensional (3D) breast cancer cell spheroids when treated with the conventional anticancer chemotherapies Cisplatin, 5-Fluorouracil (5-FU) and Doxorubicin, a Combination of the three drugs as well as the Combination plus the Ras inhibitor Salirasib. Total viability of spheroids overexpressing AQP1 were decreased by all treatments except for 5-FU, which increased total viability by 20% compared to DMSO treated controls. All treatments reduced viability of spheroids overexpressing AQP3. In contrast, only Doxorubicin, Combination and Combination + Salirasib reduced total viability of spheroids overexpressing AQP5. Thus, this study supports a significant role of AQPs in the response to conventional chemotherapies. Evaluating the role of individual proteins that contribute to resistance to chemotherapies is essential in advancing personalized medicine in breast carcinomas.

Evaluation of Quantification and Normalization Strategies for Phosphoprotein Phosphatase Affinity Proteomics: Application to Breast Cancer Signaling

Accurate quantification of proteomics data is essential for revealing and understanding biological signaling processes. We have recently developed a chemical proteomic strategy termed phosphatase inhibitor beads and mass spectrometry (PIB-MS) to investigate endogenous phosphoprotein phosphatase (PPP) dephosphorylation signaling. Here, we compare the robustness and reproducibility of status quo quantification methods for optimal performance and ease of implementation. We then apply PIB-MS to an array of breast cancer cell lines to determine differences in PPP signaling between subtypes. Breast cancer, a leading cause of cancer death in women, consists of three main subtypes: estrogen receptor-positive (ER+), human epidermal growth factor receptor two positive (HER2+), and triple-negative (TNBC). Although there are effective treatment strategies for ER+ and HER2+ subtypes, tumors become resistant and progress. Furthermore, TNBC has few targeted therapies. Therefore, there is a need to identify new approaches for treating breast cancers. Using PIB-MS, we distinguished TNBC from non-TNBC based on subtype-specific PPP holoenzyme composition. In addition, we identified an increase in PPP interactions with Hippo pathway proteins in TNBC. These interactions suggest that phosphatases in TNBC play an inhibitory role on the Hippo pathway and correlate with increased expression of YAP/TAZ target genes both in TNBC cell lines and in TNBC patients.

Androgen Receptor Status in Triple Negative Breast Cancer: Does It Correlate with Clinicopathological Characteristics?

Purpose

Triple negative breast cancer (TNBC) is a breast carcinoma subtype that neither expresses estrogen (ER) and progesterone receptors (PR) nor the human epidermal growth factor receptor 2 (HER2). Patients with TNBC have been shown to have poorer outcomes mainly owing to the limited treatment options available. However, some studies have shown TNBC tumors expressing androgen receptors (AR), raising hopes of its prognostic role.

Patients and Methods

This retrospective study investigated the expression of AR in TNBC and its relationship with known patient demographics, tumor and survival characteristics. From the records of 205 TNBC patients, 36 had available archived tissue samples eligible for AR staining. For statistical purposes, tumors were classified as either "positive" or "negative" for AR expression. The nuclear expression of AR was scored by measuring the percentage of stained tumor cells and its staining intensity.

Results

AR was expressed by 50% of the tissue samples in our TNBC cohort. The relationship between AR status with age at the time of TNBC diagnosis was statistically significant, with all AR positive TNBC patients being greater than 50 years old (vs 72.2% in AR negative TNBC). Also, the relationship between AR status and type of surgery received was statistically significant. There were no statistically significant associations between AR status with other tumor characteristics including "TNM status", tumor grade or treatments received. There was no statistically significant difference in median survival between AR negative and AR positive TNBC patients (3.5 vs 3.1 years; p = 0.581). The relationship between OS time and AR status (p = 0.581), type of surgery (p = 0.061) and treatments (p = 0.917) were not statistically significant.

Conclusion

The androgen receptor may be an important prognostic marker in TNBC, with further research warranted. This research may benefit future studies investigating receptor-targeted therapies in TNBC.

Clinical outcomes of curative-intent multimodal management of chemorefractory nonmetastatic inflammatory breast cancer

INTRODUCTION

Chemorefractory nonmetastatic inflammatory breast cancer (IBC) which progresses under neoadjuvant chemotherapy poses specific therapeutic challenges: either pursuing a curative-intent treatment with a salvage combination of radiotherapy and surgery or switching to second-line systemic treatments despite the absence of metastasis. Due to the rarity of this situation, no specific management guidelines exist and the outcomes of these patients remain uncertain. In this retrospective observational study, we aimed to report the clinical outcomes of patients treated in a curative intent for chemorefractory nonmetastatic IBC, with a multimodal salvage treatment combining radiotherapy and surgery.

MATERIALS AND METHODS

This single-center retrospective observational study included all chemorefractory nonmetastatic IBC treated at the Institut Curie (Paris, France). Overall survival (OS), disease-free survival (DFS), and locoregional relapse-free survival (LRRFS) were calculated from the time of diagnosis and from the time of neoadjuvant chemotherapy interruption.

RESULTS

Between January 2010 and January 2018, 7 patients presented with chemorefractory nonmetastatic IBC with a progressive disease during neoadjuvant chemotherapy. Overall, chemorefractory IBC patients were young (median age of 50 years), had a good performance status, and usually presented with node-positive tumors characterized by a combination of adverse histological factors such as triple-negative breast cancer (TNBC), grade III, and high proliferation index. From the date of pathological diagnosis, 1‑year OS, DFS, and LRRFS were 64.3%, 53.6%, and 71.4%, respectively. From the date of neoadjuvant chemotherapy interruption, 1‑year OS, DFS, and LRRFS were 47.6%, 19.0%, and 45.7%, respectively, and median OS, DFS, and LRRFS were 8.3, 5.0, and 5.0 months, respectively.

CONCLUSION

The prognosis of chemorefractory nonmetastatic IBC treated with a multimodal approach combining surgery and radiotherapy is particularly reserved, despite the curative intent of the salvage treatment and the lack of distant metastasis at the time of treatment. Optimal treatment modalities are still to be defined in this rare but critical presentation of IBC.

Immunogenic analysis of epitope-based vaccine candidate induced by photodynamic therapy in MDA-MB-231 triple-negative breast cancer cells

BACKGROUND

Photodynamic therapy (PDT) is used to treat tumors through selective cytotoxic effects. PDT induces damage-associated molecular patterns (DAMPs) expression, which can cause an immunogenic death cell (IDC). In this study we identified potential immunogenic epitopes generated by PDT on triple-negative breast cancer cell line (MDA-MB-231).

METHODS

MDA-MB-231 cells were exposed to PDT using ALA (160 µg/mL)/630 nm at 8 J/cm². Membrane proteins were extracted and separated by 2D PAGE. Proteins overexpressed were identified by LC-MS/MS and analyzed in silico through a peptide-HLA docking in order to identify the epitopes with more immunogenicity and antigenicity properties, as well as lower allergenicity and toxicity activity. The selected peptides were evaluated in response to macrophage activation and cytokine release by flow cytometry.

RESULTS

Differential proteins were overexpressed in the cells treated with PDT. A group of 16 peptides were identified from them, established in a rigorous selection by measuring antigenicity, immunogenicity, allergenicity, and toxicity in silico. The final selection was based on molecular dynamics, where 2 peptides showed the highest stability regarding to the RMSD value. These peptides were obtained from the proteins calreticulin and HSP90. The cytokine analysis evidenced macrophage activation by the releasing of TNF.

CONCLUSION

Two peptides were identified from calreticulin and HSP90; proteins induced by PDT in MDA-MB-231 cells. Both epitopes showed immunogenic potential as a peptide-based vaccine for triple-negative breast cancer.

Evaluation of tumor-infiltrating lymphocytes (TILs) in molecular subtypes of an Indian cohort of breast cancer patients

OBJECTIVES

Evaluation of tumor-infiltrating lymphocytes (TILs) distribution in an Indian cohort of breast cancer patients for its prognostic significance.

METHODS

A retrospective cohort of breast cancer patients from a single onco-surgeon's breast cancer clinic with a uniform treatment strategy was evaluated for TILs. Tumor sections were H&E stained and scored for the spatial distribution and percent stromal TILs infiltration by a certified pathologist. The scores were analysed for association with treatment response and survival outcomes across molecular subtypes.

RESULTS

Total 229 breast cancer tumors were evaluated. Within spatial distribution categories, intra-tumoral TILs were observed to be associated with complete pathological response and lower recurrence frequency for the entire cohort. Subtype-wise analysis of stromal TILs (sTILs) re-enforced significantly higher infiltration in TNBC compared to HER2-positive and ER-positive tumors. A favourable association of higher stromal infiltration was observed with treatment response and disease outcomes, specifically in TNBC.

CONCLUSION

Intra-tumoral TILs showed a higher proportion with favourable association with better patient outcomes in an Indian cohort, unlike western cohorts where both stromal and intra-tumoral TILs show similar association with prognosis. With further validation, TILs can be developed as a cost-effective surrogate marker for treatment response, especially in a low-resource setting such as India.

The Prognostic and Therapeutic Implications of the Chemoresistance Gene BIRC5 in Triple-Negative Breast Cancer

Chemoresistance affects TNBC patient treatment responses. Therefore, identifying the chemoresistant gene provides a new approach to understanding chemoresistance in TNBC. BIRC5 was examined in the current study as a tool for predicting the prognosis of TNBC patients and assisting in developing alternative therapies using online database tools. According to the examined studies, BIRC5 was highly expressed in 45 to 90% of TNBC patients. BIRC5 is not only abundantly expressed but also contributes to resistance to chemotherapy, anti-HER2 therapy, and radiotherapy. Patients with increased expression of BIRC5 had a median survival of 31.2 months compared to 85.8 months in low-expression counterparts (HR, 1.73; CI, 1.4−2.13; p = 2.5 × 10−7). The overall survival, disease-free survival, relapse-free survival, distant metastasis-free survival, and the complete pathological response of TNBC patients with high expression of BIRC5 who received any chemotherapy (Taxane, Ixabepilone, FAC, CMF, FEC, Anthracycline) and anti-HER2 therapy (Trastuzumab, Lapatinib) did not differ significantly from those patients receiving any other treatment. Data obtained indicate that the BIRC5 promoter region was substantially methylated, and hypermethylation was associated with higher BIRC5 mRNA expression (p < 0.05). The findings of this study outline the role of BIRC5 in chemotherapy-induced resistance of TNBC, further indicating that BIRC5 may serve as a promising prognostic biomarker that contributes to chemoresistance and could be a possible therapeutic target. Meanwhile, several in vitro studies show that flavonoids were highly effective in inhibiting BIRC5 in genetically diverse TNBC cells. Therefore, flavonoids would be a promising strategy for preventing and treating TNBC patients with the BIRC5 molecule.

Selectively Targeting Breast Cancer Stem Cells by 8-Quinolinol and Niclosamide

Cancer maintenance, metastatic dissemination and drug resistance are sustained by cancer stem cells (CSCs). Triple negative breast cancer (TNBC) is the breast cancer subtype with the highest number of CSCs and the poorest prognosis. Here, we aimed to identify potential drugs targeting CSCs to be further employed in combination with standard chemotherapy in TNBC treatment. The anti-CSC efficacy of up to 17 small drugs was tested in TNBC cell lines using cell viability assays on differentiated cancer cells and CSCs. Then, the effect of 2 selected drugs (8-quinolinol -8Q- and niclosamide -NCS-) in the cancer stemness features were evaluated using mammosphere growth, cell invasion, migration and anchorage-independent growth assays. Changes in the expression of stemness genes after 8Q or NCS treatment were also evaluated. Moreover, the potential synergism of 8Q and NCS with PTX on CSC proliferation and stemness-related signaling pathways was evaluated using TNBC cell lines, CSC-reporter sublines, and CSC-enriched mammospheres. Finally, the efficacy of NCS in combination with PTX was analyzed in vivo using an orthotopic mouse model of MDA-MB-231 cells. Among all tested drug candidates, 8Q and NCS showed remarkable specific anti-CSC activity in terms of CSC viability, migration, invasion and anchorage independent growth reduction in vitro. Moreover, specific 8Q/PTX and NCS/PTX ratios at which both drugs displayed a synergistic effect in different TNBC cell lines were identified. The sole use of PTX increased the relative presence of CSCs in TNBC cells, whereas the combination of 8Q and NCS counteracted this pro-CSC activity of PTX while significantly reducing cell viability. In vivo, the combination of NCS with PTX reduced tumor growth and limited the dissemination of the disease by reducing circulating tumor cells and the incidence of lung metastasis. The combination of 8Q and NCS with PTX at established ratios inhibits both the proliferation of differentiated cancer cells and the viability of CSCs, paving the way for more efficacious TNBC treatments.

Intestinal Microbiota Influence Doxorubicin Responsiveness in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is highly aggressive with a poor 5-year survival rate. Targeted therapy options are limited and most TNBC patients are treated with chemotherapy. This study aimed to determine whether doxorubicin (Dox) shifts the gut microbiome and whether gut microbiome populations influence chemotherapeutic responsiveness. Female BALB/c mice (n = 115) were injected with 4T1-luciferase cells (a murine syngeneic TNBC model) and treated with Dox and/or antibiotics, high-fat diet-derived fecal microbiota transplant (HFD-FMT), or exogenous lipopolysaccharide (LPS). Metagenomic sequencing was performed on fecal DNA samples. Mice that received Dox were stratified into Dox responders or Dox nonresponders. Mice from the Dox responders and antibiotics + Dox groups displayed reduced tumor weight and metastatic burden. Metagenomic analysis showed that Dox was associated with increased Akkermansia muciniphila proportional abundance. Moreover, Dox responders showed an elevated proportional abundance of Akkermansia muciniphila prior to Dox treatment. HFD-FMT potentiated tumor growth and decreased Dox responsiveness. Indeed, lipopolysaccharide, a structural component of Gram-negative bacteria, was increased in the plasma of Dox nonresponders and FMT + Dox mice. Treatment with exogenous LPS increases intestinal inflammation, reduces Dox responsiveness, and increases lung metastasis. Taken together, we show that modulating the gut microbiota through antibiotics, HFD-FMT, or by administering LPS influenced TNBC chemotherapy responsiveness, lung metastasis, and intestinal inflammation.

ZNF33A Promotes Tumor Progression and BET Inhibitor Resistance in Triple-Negative Breast Cancer

Overexpression of ZNF33A (Krüppel-type zinc finger 33A) promotes carcinogenesis in several malignant tumors. However, the biochemical role and clinical importance of ZNF33A in triple-negative breast cancer (TNBC) still need to be explored. In this study, overexpression of ZNF33A in TNBC patient tissues and cell lines led to a worse prognosis. ZNF33A promoted cell growth and facilitated the resistance of cancer cells to inhibitors of bromodomain and extraterminal domain (BET) in TNBC. ZNF33A also promoted the induction of c-Myc, the primary player for the resistance to BET inhibitors in TNBC. In conclusion, ZNF33A may be a tumor growth-promoting factor associated with TNBC prognosis, and ZNF33A repression may sensitize TNBC cells to BET inhibitors.

Elicitation of stem-like CD8+ T cell responses via lymph node-targeted chemoimmunotherapy evokes systemic tumor control

Background

Tumor-draining lymph nodes (TdLNs) are critical in the regulation of local and systemic antitumor T cell immunity and are implicated in coordinating responses to immunomodulatory therapies.

Methods

Biomaterial nanoparticles that deliver chemotherapeutic drug paclitaxel to TdLNs were leveraged to explore its effects in combination and immune checkpoint blockade (ICB) antibody immunotherapy to determine the benefit of TdLN-directed chemoimmunotherapy on tumor control.

Results

Accumulation of immunotherapeutic drugs in combination within TdLNs synergistically enhanced systemic T cell responses that led to improved control of local and disseminated disease and enhanced survival in multiple murine breast tumor models.

Conclusions

These findings suggest a previously underappreciated role of secondary lymphoid tissues in mediating effects of chemoimmunotherapy and demonstrate the potential for nanotechnology to unleashing drug synergies via lymph node targeted delivery to elicit improved response of breast and other cancers.

CircUBR5 acts as a ceRNA for miR-1179 to up-regulate UBR5 and to promote malignancy of triple-negative breast cancer

UBR5 is an E3 ubiquitin ligase and an oncogene in a panel of human cancers. However, little is known on its impacts in triple-negative breast cancer (TNBC) and even less on its relationship to circUBR5 (hsa_circ_0001819), a circular RNA derived from exons 2, 3, 4, and 5 of UBR5 gene. In this study, we detected higher expressions of both circUBR5 and UBR5 in TNBC tissues, which were associated with worse prognosis, and also in a panel of breast cancer cells, particularly in TNBC cells. Functionally, circUBR5 was crucial for sustaining the malignant growth and metastasis of TNBC cells both in vitro and in vivo. Mechanistically, the oncogenic phenotypes of circUBC5 were mediated through sponging miR-1179 and up-regulating UBR5. Concomitant silencing circUBR5 and miR-1179 abolished the anti-tumor effects of targeting circUBR5 alone. Therefore, targeting circUBR5/miR-1179/UBR5 axis may benefit the treatment of TNBCs.

Outcomes of Immediate Breast Reconstruction in Triple Negative Breast Cancer: A Propensity Score-Matched Analysis

PURPOSE

Triple negative breast cancer (TNBC) patients have a significantly worse prognosis and survival compared to non-TNBC patients. Mastectomy and immediate breast reconstruction (MIBR) is associated with higher rates of complications overall, but whether MIBR significantly increases oncological risk in TNBC patients has not been fully elucidated. Our study aimed to evaluate the oncological safety of MIBR in patients with TNBC compared to non-TNBC.

METHODS

A 6-year prospectively maintained retrospective database at The Ottawa Hospital was reviewed from January 1, 2013 to May 31, 2019. Propensity score-matching was performed using the nearest-neighbour method with a matching ratio of 2:1. Kaplan-Meier and log rank tests were performed to provide statistical comparison of disease-free interval (DFI). DFI was defined as time from MIBR to locoregional recurrence or disease-specific mortality. P-value < 0.05 indicated statistical significance.

RESULTS

Of 277 eligible patients, 153 patients were matched. The cohort consisted of 51(33%) TNBC patients and 102 (67%) non-TNBC patients after 2:1 propensity score-matching. The rates of delays to first radiochemotherapy [17 (33%) vs.14 (14%), p = 0.10], postoperative complications [13 (26%) vs. 34 (33%), p = 0.50], and locoregional recurrence [2 (1.96%) vs. 1 (1.96%), p = 1.0] were statistically similar in TNBC and non-TNBC, respectively. DFI was not significantly different in TNBC compared to non-TNBC patients (log-rank p = 1.0). There was no mortality in this cohort.

CONCLUSIONS

This 6-year retrospective 2:1 propensity score-matched cohort study demonstrated similar oncological safety for MIBR in patients with TNBC and non-TNBC.. Overall, these findings provide additional support for the oncological safety of MIBR in TNBC. . Therefore, MIBR remains a therapeutic option for patients with TNBC.

Identification of a novel mechanism for reversal of doxorubicin-induced chemotherapy resistance by TXNIP in triple-negative breast cancer via promoting reactive oxygen-mediated DNA damage

Given that triple-negative breast cancer (TNBC) lacks specific receptors (estrogen and progesterone receptors and human epidermal growth factor receptor 2) and cannot be treated with endocrine therapy, chemotherapy has remained the mainstay of treatment. Drug resistance is reportedly the main obstacle to the clinical use of doxorubicin (DOX) in this patient population. Accordingly, screening molecules related to chemoresistance and studying their specific mechanisms has clinical significance for improving the efficacy of chemotherapy in TNBC patients. Thioredoxin-interacting protein (TXNIP) is a metabolism-related protein that plays a tumor suppressor role in various malignant tumors; however, the specific role of TXNIP in tumor chemoresistance has not been reported. In the present study, we explored the potential molecular mechanism of TXNIP in the chemoresistance of TNBC for the first time. The results showed that TXNIP inhibited the proliferation of TNBC drug-resistant cells and promoted apoptosis in vitro and in vivo. Furthermore, TXNIP promoted the synthesis of reactive oxygen species (ROS) and the accumulation of DNA damage caused by DOX and increased γ-H2AX levels in a time and dose-dependent manner. Moreover, ROS scavenger pretreatment could block DNA damage induced by TXNIP and restore the resistance of TNBC resistant cells to DOX to a certain extent. In addition, we found that the small molecule c-Myc inhibitor 10058-F4 promoted TXNIP expression, increased ROS synthesis in cells, and could enhance the cytotoxicity of chemotherapy drugs in vitro and in vivo when combined with DOX. These results indicated that c-Myc inhibitor 10058-F4 could induce TXNIP upregulation in TNBC drug-resistant cells, and the upregulated TXNIP increased the accumulation of ROS-dependent DNA damage, thereby decreasing chemotherapy resistance of TNBC. Our findings reveal a new mechanism of mediating drug resistance and provide a new drug combination strategy to overcome DOX resistance in TNBC.

Linoleic Acid-Substituted Polyethyleneimine to Silence Heat Shock Protein 90B1 (HSP90B1) to Inhibit Migration of Breast Cancer Cells

INTRODUCTION

Breast cancer continues to be one of the leading causes of death in women and the lack of treatment options for distant metastasis warrants the need to identify and develop more effective approaches. The aim of this study was to identify and validate targets that are associated with the survival and migration of the breast cancer cells in vitro through RNA interference (RNAi) approach.

METHODS

Linoleic acid modified polyethylenimine (PEI) polymer was used to screen a siRNA library against numerous cell adhesion and cytoskeleton genes in MDA-MB-231 triple negative breast cell line and the functional outcome of silencing was determined by growth and migration inhibition with further target validation studies.

RESULTS

Heat shock protein 90B1 (HSP90B1) was identified as a crucial gene which is known to be involved in various breast cancer machineries, including uncontrolled proliferation and brain metastasis. The success of this approach was also due to the use of hyaluronic acid (HA) additive in lipopolymer complexes that showed a profound impact in reducing the cell viability (~50%), migration (~40%), and mRNA transcript levels (~80%) with a physiologically relevant siRNA concentration of 60 nM. The use of dicer-substrate siRNA proved to be beneficial in target silencing and a combinational treatment of integrin-β1 (ITGB1) and HSP90B1 was effective in reducing the migration of the MDA-MB-231 and MDA-MB-436 breast cancer cells.

CONCLUSION

This study demonstrated the potential to identify and silence targets using lipid modified PEI/siRNA system and highlight the importance of HSP90B1 in the growth and migration of breast cancer cells.

Comparison of the Clinicopathologic Features and T-Cell Infiltration of B7-H3 and B7-H4 Expression in Triple-negative Breast Cancer Subtypes

Previously we revealed an upregulated expression of B7-H3 and B7-H4 mRNA and protein in breast cancer, including triple-negative breast cancer (TNBC). However, little is known regarding the clinical impact and value of B7-H3 and B7-H4 in TNBC subtypes. Thus, this study evaluated the clinicopathologic effects of B7-H3 and B7-H4 mRNA and protein expression according to the TNBC subtypes. RNAscope in situ hybridization and immunohistochemistry of B7-H3 and B7-H4 was done for 186 TNBC samples using tissue microarray. Immunohistochemistry was also performed for TNBC molecular subtype-surrogate markers, CD3, and CD8. TNBCs were classified into basal-like (BL) (64.5%), luminal androgen receptor (10.8%), and unclassifiable (24.7%) subtypes. Tumor B7-H4 mRNA expression was associated with younger age at the initial diagnosis and with molecular TNBC subtypes. Expression of B7-H3 mRNA and protein in the tumor cells was negatively correlated with CD3+ and CD8+ T-cell infiltration density in the tumor and/or stromal region of TNBCs and their subtypes. High stromal B7-H3 mRNA expression was associated with poor disease-free and overall survival in the TNBCs and with overall survival in the unclassifiable subtype. Stromal B7-H3 mRNA expression was independently associated with overall survival and disease-free survival in the TNBCs and BL subtype, respectively. Our results indicate the importance of the stromal expression of B7-H3 mRNA as a prognostic factor in the TNBCs and BL subtype. The inverse relationship between B7-H3 expression and CD3+ and CD8+ T-lymphocyte infiltration represents a promising target for immunotherapy for the TNBCs, especially the BL subtype.

Extracellular Vesicles: The Landscape in the Progression, Diagnosis, and Treatment of Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a heterogeneous subtype of breast cancer (BC) with diverse biological behavior, high aggressiveness, and poor prognosis. Extracellular vesicles (EVs) are nano-sized membrane-bound vesicles secreted by nearly all cells, and are involved in physiological and pathological processes. EVs deliver multiple functional cargos into the extracellular space, including proteins, lipids, mRNAs, non-coding RNAs (ncRNAs), and DNA fragments. Emerging evidence confirms that EVs enable pro-oncogenic secretome delivering and trafficking for long-distance cell-to-cell communication in shaping the tumor microenvironment (TME). The transferred tumor-derived EVs modify the capability of invasive behavior and organ-specific metastasis in recipient cells. In addition, TNBC cell-derived EVs have been extensively investigated due to their promising potential as valuable biomarkers for diagnosis, monitoring, and treatment evaluation. Here, the present review will discuss the recent progress of EVs in TNBC growth, metastasis, immune regulation, as well as the potential in TNBC diagnosis and treatment application, hoping to decipher the advantages and challenges of EVs for combating TNBC.

Progress and pitfalls in the use of immunotherapy for patients with triple negative breast cancer

INTRODUCTION

Triple negative breast cancer (TNBC) is an area of high unmet medical need in terms of new effective treatment strategies. Although breast cancer is traditionally considered a 'cold' tumor type, TNBC is the most appropriate subtype for immunotherapeutic strategies; this is due to the high level of tumor infiltrating lymphocytes, PD-L1 expression and tumor mutational burden relative to other breast cancer subtypes.

AREAS COVERED

This review examines the use of immunotherapeutic strategies in early and advanced TNBC. The paper summarizes data on novel promising immunomodulatory approaches that have been explored in early phase trials and discusses the pitfalls and limitations often encountered in clinical research.

EXPERT OPINION

PD-1-blockade is approved for stage II/III TNBC and for first-line treatment of PD-L1-positive TNBC patients with metastatic disease and should be considered standard of care. However, question marks and difficulties remain; these include the identification of predictive biomarkers to select patients who benefit from the addition of PD1-blockade and the balance between efficacy and long-term toxicity for an individual patient. Numerous treatment combinations and new immunotherapeutic strategies beyond PD1 blockade are being evaluated, thus reflecting a promising evolution of a more personalized approach, and extended clinical benefit in TNBC.

Novel Psychoactive Substances: The Razor's Edge between Therapeutical Potential and Psychoactive Recreational Misuse

BACKGROUND

Novel psychoactive substances (NPS) are compounds of natural and synthetic origin, similar to traditional drugs of abuse. NPS are involved in a contemporary trend whose origin lies in a thinner balance between legitimate therapeutic drug research and legislative control. The contemporary NPS trend resulted from the replacement of MDMA by synthetic cathinones in 'ecstasy' during the 2000s. The most common NPS are synthetic cannabinoids and synthetic cathinones. Interestingly, during the last 50 years, these two classes of NPS have been the object of scientific research for a set of health conditions.

METHODS

Searches were conducted in the online database PubMed using boolean equations.

RESULTS

Synthetic cannabinoids displayed protective and therapeutic effects for inflammatory, neurodegenerative and oncologic pathologies, activating the immune system and reducing inflammation. Synthetic cathinones act similarly to amphetamine-type stimulants and can be used for depression and chronic fatigue.

CONCLUSIONS

Despite the scientific advances in this field of research, pharmacological application of NPS is being jeopardized by fatalities associated with their recreational use. This review addresses the scientific achievements of these two classes of NPS and the toxicological data, ending with a reflection on Illicit and NPS control frames.

Blood Circulating Non-Coding RNAs for the Clinical Management of Triple-Negative Breast Cancer

Triple negative breast cancer (TNBC) represents the most aggressive subtype of breast cancer, and is related to unfavorable prognosis and limited treatment strategies. Currently, there is a lack of reliable biomarkers allowing for the clinical management of TNBC. This is probably caused by a complex molecular background, leading to the development and establishment of a unique tumor phenotype. Recent studies have reported non-coding RNAs (ncRNAs) not only as the most promising class of molecular agents with a high applicability to manage human cancers, including TNBC, but also as robust and non-invasive biomarkers that are able to be monitored in blood circulation, with the application of liquid biopsy. There is a lack of papers discussing the role of blood-circulating ncRNAs as diagnostic, predictive, and prognostic biomarkers for TNBC. In this paper, we summarized the available literature reports on the utility of blood-circulating ncRNAs for TNBC management. Additionally, we supplemented this review by bioinformatics analysis, for better understanding of the role of ncRNAs' machinery in the development of a unique TNBC phenotype.

Radiomics in Triple Negative Breast Cancer: New Horizons in an Aggressive Subtype of the Disease

In the last decade, the analysis of the medical images has evolved significantly, applications and tools capable to extract quantitative characteristics of the images beyond the discrimination capacity of the investigator's eye being developed. The applications of this new research field, called radiomics, presented an exponential growth with direct implications in the diagnosis and prediction of response to therapy. Triple negative breast cancer (TNBC) is an aggressive breast cancer subtype with a severe prognosis, despite the aggressive multimodal treatments applied according to the guidelines. Radiomics has already proven the ability to differentiate TNBC from fibroadenoma. Radiomics features extracted from digital mammography may also distinguish between TNBC and non-TNBC. Recent research has identified three distinct subtypes of TNBC using IRM breast images voxel-level radiomics features (size/shape related features, texture features, sharpness). The correlation of these TNBC subtypes with the clinical response to neoadjuvant therapy may lead to the identification of biomarkers in order to guide the clinical decision. Furthermore, the variation of some radiomics features in the neoadjuvant settings provides a tool for the rapid evaluation of treatment efficacy. The association of radiomics features with already identified biomarkers can generate complex predictive and prognostic models. Standardization of image acquisition and also of radiomics feature extraction is required to validate this method in clinical practice.