Metastatic triple negative breast cancer: Optimizing treatment options, new and emerging targeted therapies

Self-Assembled Dual-Targeted Epirubicin-Hybrid Polydopamine Nanoparticles for Combined Chemo-Photothermal Therapy of Triple-Negative Breast Cancer

PURPOSE

Folic acid and cyclic arginylglycylaspartic acid peptides were introduced to the surface of negatively charged lipid-coated hybrid polydopamine-cysteine cores for the delivery of epirubicin (EPI) (E/PCF-NPs). The combined chemo-photothermal therapy using E/PCF-NPs for triple-negative breast cancer was evaluated.

MATERIALS AND METHODS

The temperature elevation and thermal toxicity of nanoparticles were studied. The morphology and properties of E/PCF-NPs were characterized by transmission electron microscopy, scanning electron microscopy, and atomic force microscopy. Physicochemical properties, including particle size, zeta potential, drug loading, entrapment efficiency (EE%), stability and in vitro release, were determined. The cell viability, reactive oxygen species (ROS) levels, ratios of oxidized nicotinamide adenine dinucleotide to its reduced form (NAD+/NADH), apoptosis assays, and cellular uptake of E/PCF-NPs were determined on 4T1 cells. Pharmacokinetic studies and tissue distributions were performed and detected by an ultra-high performance liquid chromatography/mass spectrometry system. The antitumor effects of E/PCF-NPs under near-infrared (NIR) laser irradiation were also evaluated.

RESULTS

The sphere-like morphology of E/PCF-NPs showed a high EE%, uniform size of 106.7 nm, remarkable stability, and highly improved cytotoxicity under NIR laser, when compared to that of photothermal treatment alone. In vitro release of EPI from E/PCF-NPs was pH sensitive, and a greater response was achieved under NIR laser irradiation. Compared to chemotherapy or photothermal treatment alone, the combined treatment in vitro significantly inhibited the survival rate of 4T1 cells to 17.7%, induced ROS generation, and reduced NAD+/NADH significantly. Treatment with E/PCF-NPs under irradiation induced 4T1 cell apoptosis in approximately 93.6% cells. In vitro cellular uptake of E/PCF-NPs was time-dependent. The long-circulating and higher tumor accumulation of E/PCF-NPs resulted in complete ablation of breast tumor tissue through the enhanced photothermal effect by NIR laser irradiation-mediated cell apoptosis.

CONCLUSION

E/PCF-NPs show enhanced anti-cancer effects due to synergistic effects of chemotherapy with photothermal therapy and may be potential therapeutic agents for cancer treatment.

[EGFR tyrosine kinase inhibitor HS-10296 induces autophagy and apoptosis in triplenegative breast cancer MDA-MB-231 cells]

OBJECTIVE

To investigate the inhibitory effect of epidermal growth factor receptor tyrosine kinase inhibitor (EGFRTKI) HS-10296 on the proliferation of triple-negative breast cancer (TNBC) MDA-MB-231 cells and explore the possible molecular mechanism.

METHODS

MDA-MB-231 cells were treated with HS-10296 for 24, 48, or 72 h, and CCK-8 assay was used to assess the changes in the cell viability. The inhibitory effect of HS-10296 on cell proliferation was determined by clonogenic assay. JC-1 and flow cytometry were employed for analyzing the cell apoptosis, and the ultrastructure of the cells was observed under electron microscope. After pretreatment with autophagy inhibitor chloroquine (CQ), MDA-MB-231 cells were divided into control group, CQ treatment group, HS-10296 (4 and 6 μmol/L) treatment groups and combined treatment groups, and the sensitivity of the treated cells to HS-10296 was determined using CCK-8 assay. The effects of HS-10296 on EGFR pathway and apoptosis- and autophagy-related proteins in MDA-MB-231 cells were investigated using Western blotting.

RESULTS

HS-10296 significantly inhibited the proliferation of MDA-MB-231 cells with IC₅₀ values at 24, 48 and 72 h of 8.393, 2.777 and 2.016 μmol/L, respectively. JC-1 and flow cytometry showed that HS-10296 induced obvious apoptosis of MDA-MB-231 cells, which showed an apoptosis rate of (21.63 ± 2.97)% following treatment with 8 μmol/L HS-10296. Autophagy vesicles were observed in the cells treated with HS-10296 under electron microscope. In MDA-MB-231 cells pretreated with CQ, inhibition of autophagy significantly enhanced HS-10296-induced cell death. Western blotting showed that the apoptosis-related protein caspase-3 was activated after HS-10296 treatment to cut its substrate PARP. The expression of autophagy-related protein light chain 3B (LC3B) was significantly enhanced after HS-10296 treatment (P < 0.01), which also resulted in inhibited phosphorylation of EGFR and AKT proteins in the cells.

CONCLUSIONS

HS-10296 can inhibit the proliferation and induce autophagy and apoptosis of MDA-MB-231 cells by inhibiting the EGFR/PI3K/AKT signaling pathway.

Current advances in the diagnosis and personalized treatment of breast cancer: lessons from tumor biology

Breast cancer treatment has advanced enormously in the last decade. Most of this is due to advances reached in the knowledge regarding tumor biology, mainly in the field of diagnosis and treatment. This review brings information about how the genomics-based information contributed to advances in breast cancer diagnosis and prognosis perspective, as well as presents how tumor biology discoveries fostered the main therapeutic approaches available to treat such patients, based on a personalized point of view.

Protective effect of hsa-miR-570-3p targeting CD274 on triple negative breast cancer by blocking PI3K/AKT/mTOR signaling pathway

To find out the role of hsa-miR-570-3p targeting CD274 in triple negative breast cancer (TNBC) via PI3K/AKT/mTOR signaling pathway. Hsa-miR-570-3p and CD274 expressions in 175 TNBC patients were detected by qRT-PCR and immunohistochemistry respectively. The human TNBC cell lines (MDA-MB-468 and MDA-MB-231) were used to verify the targeting relationship between hsa-miR-570-3p and CD274 via dual-luciferase reporter gene assay. Then, MDA-MB-468 and MDA-MB-231 cells were divided into Blank, miR-NC, miR-570-3p mimics, NC siRNA, CD274 siRNA, and miR-570-3p inhibitors + CD274 siRNA groups. Next, the biological activities of cells were detected by MTT, Cell-Light EdU, Annexin-V-FITC/PI, wound healing and Transwell invasion assays. Western blotting was conducted to detect protein expressions.MiR-570-3p expression was lower in tumor tissues than that in adjacent normal tissues, which was more obvious in CD274-positive TNBC patients, which targeted CD274 in TNBC cell lines. MiR-570-3p inhibited cell proliferation, invasion and migration, but induced cell apoptosis accompanying the upregulation of apoptotic proteins and downregulation of anti-apoptotic protein. CD274 siRNA had the similar results of miR-570-3p mimics, which could be reversed by miR-570-3p inhibitors. Besides, both miR-570-3p mimics and CD274 siRNA blocked PI3K/AKT/mTOR signaling pathway in TNBC cell lines. Hsa-miR-570-3p was downregulated and CD274 was upregulated in TNBC patients. Besides, hsa-miR-570-3p targeted CD274 to inhibit cell proliferation, invasion, migration, and induce cell apoptosis, which may be related to the suppression of PI3K/AKT/mTOR pathway.

KLF4 defines the efficacy of the epidermal growth factor receptor inhibitor, erlotinib, in triple-negative breast cancer cells by repressing the EGFR gene

Background

Triple-negative breast cancer (TNBC) is characterized by high rates of recurrence and poor overall survival. This is due, in part, to a deficiency of targeted therapies, making it essential to identify therapeutically targetable driver pathways of this disease. While epidermal growth factor receptor (EGFR) is expressed in 60% of TNBCs and drives disease progression, attempts to inhibit EGFR in unselected TNBC patients have had a marginal impact on outcomes. Hence, we sought to identify the mechanisms that dictate EGFR expression and inhibitor response to provide a path for improving the utility of these drugs. In this regard, the majority of TNBCs express low levels of the transcription factor, Krüppel-like factor 4 (KLF4), while a small subset is associated with high expression. KLF4 and EGFR have also been reported to have opposing actions in TNBC. Thus, we tested whether KLF4 controls the expression of EGFR and cellular response to its pharmacological inhibition.

Methods

KLF4 was transiently overexpressed in MDA-MB-231 and MDA-MB-468 cells or silenced in MCF10A cells. Migration and invasion were assessed using modified Boyden chamber assays, and proliferation was measured by EdU incorporation. Candidate downstream targets of KLF4, including EGFR, were identified using reverse phase protein arrays of MDA-MB-231 cells following enforced KLF4 expression. The ability of KLF4 to suppress EGFR gene and protein expression and downstream signaling was assessed by RT-PCR and western blot, respectively. ChIP-PCR confirmed KLF4 binding to the EGFR promoter. Response to erlotinib in the context of KLF4 overexpression or silencing was assessed using cell number and dose-response curves.

Results

We report that KLF4 is a major determinant of EGFR expression and activity in TNBC cells. KLF4 represses transcription of the EGFR gene, leading to reduced levels of total EGFR, its activated/phosphorylated form (pEGFR), and its downstream signaling intermediates. Moreover, KLF4 suppression of EGFR is a necessary intermediary step for KLF4 to inhibit aggressive TNBC phenotypes. Most importantly, KLF4 dictates the sensitivity of TNBC cells to erlotinib, an FDA-approved inhibitor of EGFR.

Conclusions

KLF4 is a major regulator of the efficacy of EGFR inhibitors in TNBC cells that may underlie the variable effectiveness of such drugs in patients.

Triple-negative breast cancer molecular subtyping and treatment progress

Triple-negative breast cancer (TNBC), a specific subtype of breast cancer that does not express estrogen receptor (ER), progesterone receptor (PR), or human epidermal growth factor receptor 2 (HER-2), has clinical features that include high invasiveness, high metastatic potential, proneness to relapse, and poor prognosis. Because TNBC tumors lack ER, PR, and HER2 expression, they are not sensitive to endocrine therapy or HER2 treatment, and standardized TNBC treatment regimens are still lacking. Therefore, development of new TNBC treatment strategies has become an urgent clinical need. By summarizing existing treatment regimens, therapeutic drugs, and their efficacy for different TNBC subtypes and reviewing some new preclinical studies and targeted treatment regimens for TNBC, this paper aims to provide new ideas for TNBC treatment.

Knockdown of Kinase Family 15 Inhibits Cancer Cell Proliferation In vitro and its Clinical Relevance in Triple-Negative Breast Cancer

PURPOSE

Breast cancer is the most prevalent malignancy and the leading cause of death among women. Triple-negative breast cancer (TNBC) is a subtype of breast cancer and shows a distinctly aggressive nature with higher rates of relapse and shorter overall survival in the metastatic setting compared to other subtypes of breast cancer. This study aimed to assess the effect of KIF15 on various clinicopathological characteristics, survival analysis, and cell proliferation in triple-negative breast cancer, which has not been reported to our knowledge.

METHODS

A total of 165 patients with triple-negative breast cancer were enrolled and clinical data were obtained, Mann-Whitney U analysis was performed to assess the correlation between the expression of KIF15 and clinical pathological characteristics of TNBC patients. Survival analysis was performed by Kaplan-Meier analysis and Log-rank test. The expression levels of KIF15 in cancer tissues and adjacent tissues were evaluated via Sign test. Lentivirus was used to down-regulate the expression of KIF15 in TNBC cells. The cell proliferation, colony formation capacity and apoptosis were examined by MTT, Giemsa staining and flow cytometry assay, respectively.

RESULTS

Our results showed that, among the 165 TNBC patients, the expression of KIF15 was positive correlation with clinicopathological features of TNBC. In addition, KIF15 low-expression group showed higher disease-free survival than KIF15 highexpression group and univariate analysis showed that KIF15 high-expression group appeared higher mortality than KIF low-expression group (P ≤ 0.05). Meanwhile, the expression levels of KIF15 in cancer tissue notably up-regulated in comparison with adjacent tissue. In vitro, knockdown of KIF15 significantly promoted cell apoptosis and suppressed cell proliferation and colony formation of TNBC cells.

CONCLUSION

By utilizing survival analysis, we found that high-expression of KIF15 in the TNBC samples were associated with poorer overall survival, while the anti-tumor effect of KIF15 knockdown was also confirmed at the cellular level in vitro. Taken together, KIF15 can be applied as a potential diagnostic and therapeutic target in TNBC.

Knockdown of A-kinase anchor protein 4 inhibits proliferation of triple-negative breast cancer cells in vitro and in vivo

Triple-negative breast cancers are the most aggressive subtypes with poor prognosis due to lack of targeted cancer therapy. Recently, we reported an association of A-kinase anchor protein 4 expression with various clinico-pathological parameters of breast cancer patients. In this context, we examined the effect of knockdown of A-kinase anchor protein 4 on cell cycle, apoptosis, cellular proliferation, colony formation, migration, and invasion in triple-negative breast cancer cells. We also examined the synergistic cytotoxic effect of paclitaxel on A-kinase anchor protein 4 downregulated triple-negative breast cancer cells. Knockdown of A-kinase anchor protein 4 resulted in significant reduction in cellular growth and migratory abilities. Interestingly, we also observed enhanced cell death in A-kinase anchor protein 4 downregulated cells treated with paclitaxel. Knockdown of A-kinase anchor protein 4 in cell cycle resulted in G0/G1 phase arrest. Knockdown of A-kinase anchor protein 4 also led to increased reactive oxygen species generation as a result of upregulation of NOXA and CHOP. In addition, levels of cyclins, cyclin-dependent kinases, anti-apoptotic molecules, and mesenchymal markers were reduced in A-kinase anchor protein 4 downregulated cells. Moreover, downregulation of A-kinase anchor protein 4 also caused tumor growth reduction in in vivo studies. These data together suggest that A-kinase anchor protein 4 downregulation inhibits various malignant properties and enhances the cytotoxic effect of paclitaxel, and this combinatorial approach could be useful for triple-negative breast cancer treatment.

Saikosaponin A Inhibits Triple-Negative Breast Cancer Growth and Metastasis Through Downregulation of CXCR4

Purpose: Due to a lack of recognized molecular targets for therapy, patients with triple-negative breast cancer (TNBC), unlike other subtypes of breast cancers, generally have not benefited from the advances made with targeted agents. The CXCR4/SDF-1 axis is involved in tumor growth and metastasis of TNBC. Therefore, down-regulation of the expression of CXCR4 in cancer cells is a potential therapeutic strategy for inhibiting primary tumor growth and metastasis of TNBC. In order to identify bioactive compounds that inhibit the expression of CXCR4 in traditional Chinese medicines, we investigated the capacity of saikosaponin A (SSA), one of the active ingredients isolated from Radix bupleuri, to affect CXCR4 expression and function in TNBC cells. Methods: Analyses of cell growth, migration, invasion, and protein expression were performed. Knockdowns by small interfering RNA (siRNA) and non-invasive bioluminescence were also used. Results: SSA reduced proliferation and colony formation of SUM149 and MDA-MB-231 cells. SSA inhibited migration and invasion of TNBC cells. For mice, SSA inhibited primary tumor growth and reduced lung metastasis of highly metastatic, triple-negative 4T1-luc cells. SSA inhibited CXCR4 expression but did not regulate CXCR7 expression in vitro and in vivo. The inhibitory effects on the migration and invasion of TNBC cells were reversed by down-regulation of CXCR4 expression. In addition, SSA inactivated the Akt/mTOR signaling pathway and inhibited MMP-9 and MMP-2 expression. Conclusions: The results show that SSA exerts an anti-TNBC effect through the inhibition of CXCR4 expression and thus has the potential to be a candidate therapeutic agent for TNBC patients.

Immunotherapy: The end of the "dark age" for metastatic triple-negative breast cancer?

The lack of effective therapies for metastatic triple-negative breast cancer (mTNBC) highlights the need for the development of novel treatment strategies. The cornerstone of treatment has long been represented by chemotherapy. Relevant evidence has recently emerged regarding the efficacy of immune checkpoint inhibitors, with the demonstration of a statistically significant improvement of progression-free survival with the addition of atezolizumab to nab-paclitaxel in the first-line treatment of mTNBC, accompanied by a substantial overall survival benefit in the PD-L1-positive subgroup. Despite this, it is necessary to identify the biomarkers that could allow a better selection of patients and combination regimens.

Patient-reported outcomes in patients with a germline BRCA mutation and HER2-negative metastatic breast cancer receiving olaparib versus chemotherapy in the OlympiAD trial

BACKGROUND

The phase III OlympiAD study (NCT02000622) showed a statistically significant progression-free survival benefit with olaparib versus chemotherapy treatment of physician's choice (TPC) in patients with a germline BRCA mutation and human epidermal growth factor receptor 2-negative metastatic breast cancer. From this study, we report the effect of olaparib on health-related quality of life (HRQoL).

METHODS

Patients were randomised 2:1 to olaparib monotherapy (300 mg twice daily) or single-agent TPC. The primary HRQoL end-point was mean change from baseline in the two-item global health status/QoL score determined from patient-completed European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30-item module (EORTC QLQ-C30) questionnaires and assessed using a mixed model for repeated measures. Symptoms and functioning domains, best overall response and time to deterioration of QoL were also evaluated.

RESULTS

Overall questionnaire compliance rates were 93.2% for olaparib and 76.3% for TPC. Between-treatment global health status/QoL comparison showed a significant improvement in the olaparib arm versus the TPC arm, with mean change of 3.9 (standard deviation 1.2) versus -3.6 (2.2), a difference of 7.5 points (95% confidence interval [CI]: 2.48, 12.44; P = 0.0035). A higher proportion of patients in the olaparib arm showed a best overall response of 'improvement' in global health status/QoL (33.7% vs 13.4%). Median time to global health status/QoL deterioration was not reached in olaparib patients and was 15.3 months for TPC patients (hazard ratio: 0.44 [95% CI: 0.25, 0.77]; P = 0.004). For EORTC QLQ-C30 symptoms and functioning subscales, only nausea/vomiting symptom score was worse in the olaparib arm than in the TPC arm (across all visits compared with baseline).

CONCLUSION

HRQoL was consistently improved for patients treated with olaparib, compared with chemotherapy TPC.

SGLT1 is required for the survival of triple-negative breast cancer cells via potentiation of EGFR activity

Sodium/glucose cotransporter 1 (SGLT1), an essential active glucose transport protein that helps maintain high intracellular glucose levels, was previously shown to interact with epidermal growth factor receptor (EGFR); the SGLT1-EGFR interaction maintains intracellular glucose levels to promote survival of cancer cells. Here, we explore the role of SGLT1 in triple-negative breast cancer (TNBC), which is the most aggressive type of breast cancer. We performed TCGA analysis coupled to in vitro experiments in TNBC cell lines as well as in vivo xenografts established in the mammary fat pad of female nude mice. Tissue microarrays of TNBC patients with information of clinical-pathological parameters were also used to investigate the expression and function of SGLT1 in TNBC. We show that high levels of SGLT1 are associated with greater tumour size in TNBC. Knockdown of SGLT1 compromises cell growth in vitro and in vivo. We further demonstrate that SGLT1 depletion results in decreased levels of phospho-EGFR, and as a result, the activity of downstream signalling pathways (such as AKT and ERK) is inhibited. Hence, targeting SGLT1 itself or the EGFR-SGLT1 interaction may provide novel therapeutics against TNBC.

Treatment patterns, health care resource use and outcomes in metastatic triple-negative breast cancer in Germany: retrospective chart review study (OBTAIN)

Background: There is limited data on the real-life situation and outcomes of patients with metastatic triple-negative breast cancer (mTNBC) in Germany. The aim of this chart review was to describe the current treatment patterns, resource use and outcomes in this patient group. Methods: Retrospective data collection in 30 gyneco-oncological sites (hospitals and office-based) across Germany between January and April 2017. Index date was defined as initiation of treatment with gemcitabine, vinorelbin, capecitabine or eribulin therapy following discontinuation of taxane and/or anthracycline therapy. Results: In the 91 evaluable patients, median time between primary diagnosis and index date was 20.9 months (range 0-187 months). Ten percent of patients had no distant metastases, while 57% had newly diagnosed metastases. Cancer stage at index date was mostly IV (82 patients). A number of 135 different regimens (monotherapy or combination therapy) were used. For first-line chemo treatment, 29 patients received monotherapy and 54 patients combination therapy. Bevacizumab and paclitaxel were also the most frequently used single substances among all therapy lines together and for first-line therapy. While taxanes were at least occasionally administered for second-line therapy, no patient received taxanes for third-line therapy. Chemotherapy modifications in terms of dose reduction or treatment interruption were rare. However, the therapy was terminated in more than two thirds of all cases. Fifty-nine patients were hospitalized at least once. For first-, second- and third-line therapy, median overall survival was 19.1/10.8/14.6 months, and median progression-free survival was 7.7/2.5/5.6 months. Conclusion: In clinical routine, a wide variety of treatment approaches is applied, while outcomes in terms of survival are poor. New treatment options are needed for this challenging tumor type.

Multimodal Polysilsesquioxane Nanoparticles for Combinatorial Therapy and Gene Delivery in Triple-Negative Breast Cancer

Multifunctional hybrid nanoparticles are being developed to carry a wide variety of therapeutic and imaging agents for multiple biomedical applications. Polysilsesquioxane (PSilQ) nanoparticles are a promising hybrid platform with numerous advantages to be used as a delivery system. In this report, we demonstrate the ability of a stimuli-responsive PSilQ-based platform to transport and deliver simultaneously protoporphyrin IX, curcumin, and RNA interference inducers inside human cells. This multimodal delivery system shows a synergistic performance for the combined phototherapy and chemotherapy of triple-negative breast cancer and can be used for efficient transfection of therapeutic nucleic acids. The current work represents the first report of using the PSilQ platform for the combined phototherapy and chemotherapy and gene delivery.

Anticancer activity of palladium-based complexes against triple-negative breast cancer

Treatment of triple-negative breast carcinoma (TNBC) remains an unmet medical need with no targeted therapy available to date. Accounting for 10-30% of all human breast cancer tumors, this mammary carcinoma subtype has a particularly poor prognosis owing to its high metastatic potential, aggressive biology and limited pharmacological treatment options. Platinum chemotherapeutics are the mainstay therapy in patients with TNBC but their clinical use is limited by severe toxicity and acquired resistance. Palladium-based complexes are appealing alternative metal-based drugs because of significant similarities regarding structure and coordination chemistry with the platinum agents. This review summarizes the knowledge gathered so far on 121 Pd(II) complexes, emphasizing their anticancer activity and putative pharmacological targets toward TNBC.

Sacituzumab Govitecan-hziy in Refractory Metastatic Triple-Negative Breast Cancer

BACKGROUND

Standard chemotherapy is associated with low response rates and short progression-free survival among patients with pretreated metastatic triple-negative breast cancer. Sacituzumab govitecan-hziy is an antibody-drug conjugate that combines a humanized monoclonal antibody, which targets the human trophoblast cell-surface antigen 2 (Trop-2), with SN-38, which is conjugated to the antibody by a cleavable linker. Sacituzumab govitecan-hziy enables delivery of high concentrations of SN-38 to tumors.

METHODS

We conducted a phase 1/2 single-group, multicenter trial involving patients with advanced epithelial cancers who received sacituzumab govitecan-hziy intravenously on days 1 and 8 of each 21-day cycle until disease progression or unacceptable toxic effects. A total of 108 patients received sacituzumab govitecan-hziy at a dose of 10 mg per kilogram of body weight after receiving at least two previous anticancer therapies for metastatic triple-negative breast cancer. The end points included safety; the objective response rate (according to Response Evaluation Criteria in Solid Tumors, version 1.1), which was assessed locally; the duration of response; the clinical benefit rate (defined as a complete or partial response or stable disease for at least 6 months); progression-free survival; and overall survival. Post hoc analyses determined the response rate and duration, which were assessed by blinded independent central review.

RESULTS

The 108 patients with triple-negative breast cancer had received a median of 3 previous therapies (range, 2 to 10). Four deaths occurred during treatment; 3 patients (2.8%) discontinued treatment because of adverse events. Grade 3 or 4 adverse events (in ≥10% of the patients) included anemia and neutropenia; 10 patients (9.3%) had febrile neutropenia. The response rate (3 complete and 33 partial responses) was 33.3% (95% confidence interval [CI], 24.6 to 43.1), and the median duration of response was 7.7 months (95% CI, 4.9 to 10.8); as assessed by independent central review, these values were 34.3% and 9.1 months, respectively. The clinical benefit rate was 45.4%. Median progression-free survival was 5.5 months (95% CI, 4.1 to 6.3), and overall survival was 13.0 months (95% CI, 11.2 to 13.7).

CONCLUSIONS

Sacituzumab govitecan-hziy was associated with durable objective responses in patients with heavily pretreated metastatic triple-negative breast cancer. Myelotoxic effects were the main adverse reactions. (Funded by Immunomedics; IMMU-132-01 ClinicalTrials.gov number, NCT01631552.).

Hydrophobicity may enhance membrane affinity and anti-cancer effects of Schiff base vanadium(v) catecholate complexes

Anti-cancer activities of vanadium compounds have generated recent interest because of a combination of desirable properties for chemotherapy, i.e., strong cytotoxicities, anti-metastatic activities and relatively low systemic toxicities. Certain hydrophobic vanadium(v) Schiff base/catecholate compounds, which as shown herein, have increased stability in aqueous media and affinity for membrane interfaces. Depending on their hydrophobicity, they may be able to enter cells intact. In this manuscript, two hydrophobic V(v) catecholate substituted analogues, [VO(Hshed)(cat)] and [VO(Hshed)(dtb)], (Hshed = N-(salicylideneaminato)-N'-(2-hydroxyethyl)-1,2-ethanediamine, cat = pyrocatechol, and dtb = 3,5-di(tert-butyl)catechol and the vanadium(v) precursor [V(O)2(Hshed)]) were synthesized for their ability to interact with membranes and their anti-cancer effects. Using 51V and 1H NMR spectroscopy, the presence and location of the free ligand, H2shed, and the three V(v) complexes were examined in a model membrane microemulsion system. The stability of the three complexes was measured in aqueous solution, cell media and an inhomogeneous microemulsion system. Our results demonstrated that free ligand H2shed and the intact V(v) complexes associated with the interface but that the V-complexes hydrolyzed to some extent because oxovanadates were observed by 51V NMR spectroscopy and decreasing complex by absorption spectroscopy in cell media. When determining the effects of V(v) catecholate complexes on bone cancer cells, the strongest effects were observed with the more stable hydrophobic complex [VO(Hshed)(dtb)] that was able to best associate and penetrate the model membrane system intact. These studies are consistent with the membrane permeability studies being a good predictor for in vitro cytotoxicity assays because [VO(Hshed)(dtb)] can pass through the cellular membrane intact, which may enhance its anti-cancer activities.

Fenton-reaction-stimulative nanoparticles decorated with a reactive-oxygen-species (ROS)-responsive molecular switch for ROS amplification and triple negative breast cancer therapy

P@P/H NPs were rapidly disintegrated in response to ROS, and this further enhanced ROS level in tumor cells via the Fenton reaction.

Real-life clinical pattern, management, and survival in Thai patients with early-stage or metastatic triple-negative breast cancer

OBJECTIVES

To characterize the clinical pattern and evaluate real-life practices in the management of patients with triple-negative breast cancer (TNBC) in Thailand.

METHODS

In this multicenter, prospective, observational cohort, females (aged ≥18 years) with histologically and immunohistochemically confirmed TNBC were enrolled. Patient data was collected at four study visits-an inclusion visit (for enrollment), and three subsequent follow-up visits at 12±1, 24±1, and 36±1 months after completion of first day of any planned chemotherapy.

RESULTS

Of the 293 enrolled patients, 262 (89.4%) had early-stage TNBC (Stage I: 46 patients, Stage II: 151 patients, and Stage III: 65 patients) and 31 (10.6%) had metastatic TNBC (mTNBC). Chemotherapy was prescribed to 95.4% of the early-stage patients and to 100.0% of the mTNBC patients; most commonly as anthracycline-based in combination with cyclophosphamide and other agents. Patients' performance status and consensus guidelines were the major factors affecting choice of treatment. In early-stage patients, median disease-free survival (DFS) and overall survival (OS) had not been reached for Stage I and II patients, and were calculated to be 37.0 months and 40.0 months, respectively, in Stage III patients. In mTNBC patients, progression-free survival (PFS) and OS were found to be 10.0 months and 14.0 months, respectively. In Stage III patients, anthracycline-based regimens were found to be associated with increase in DFS (p = 0.0181) and OS (p = 0.0027) compared to non-anthracycline-based regimens. In mTNBC patients, non-taxane-based regimens were associated with an increase in PFS (p = 0.0025). The 3-year survival rates in early-stage and mTNBC patients were 85.0% and 21.0%, respectively.

CONCLUSION

Clinical management of TNBC in Thailand follows the general guidelines for treatment of TNBC. However, prognosis and survival outcomes are suboptimal, especially in progressive disease. This study is the first assessment in the existing practices in which the results could pave to way to improve the treatment outcome of TNBC in Thailand.

Dancing from bottoms up - Roles of the POZ-ZF transcription factor Kaiso in Cancer

The POZ-ZF transcription factor Kaiso was discovered two decades ago as a binding partner for p120^ctn. Since its discovery, roles for Kaiso in diverse biological processes (epithelial-to-mesenchymal transition, apoptosis, inflammation) and several signalling pathways (Wnt/β-catenin, TGFβ, EGFR, Notch) have emerged. While Kaiso's biological role in normal tissues has yet to be fully elucidated, Kaiso has been increasingly implicated in multiple human cancers including colon, prostate, ovarian, lung, breast and chronic myeloid leukemia. In the majority of human cancers investigated to date, high Kaiso expression correlates with aggressive tumor characteristics including proliferation and metastasis, and/or poor prognosis. More recently, interest in Kaiso stems from its apparent correlation with racial disparities in breast and prostate cancer incidence and survival outcomes in people of African Ancestry. This review discusses Kaiso's role in various cancers, and Kaiso's potential for driving racial disparities in incidence and/or outcomes in people of African ancestry.

The efficacy of gabapentin in reducing pain intensity and morphine consumption after breast cancer surgery: A meta-analysis

BACKGROUND

The purpose of this meta-analysis from randomized controlled trials (RCTs) was to determine the efficacy and safety of the preoperative use of gabapentin for the treatment of acute and chronic postoperative pain following breast cancer surgery.

METHODS

In November 2017, a systematic computer-based search was conducted in PubMed, Embase, Web of Science, Cochrane Library, and Google databases. RCTs comparing gabapentin with placebo in patients undergoing breast cancer surgery were retrieved. The primary endpoint was the visual analog scale (VAS) after surgery and 24 hours after surgery and total morphine consumption. The secondary outcomes were incidence of chronic pain and complications (the incidence of nausea). Software Stata 12.0 was used for meta-analysis.

RESULTS

Finally, 9 RCTs were included in the meta-analysis. Results indicated that gabapentin was associated with reduced pain scores after surgery and 24 hours after surgery. Meanwhile, oral gabapentin was associated with a reduction of the total morphine consumption after breast cancer surgery. Similarly, gabapentin was associated with a reduction in the incidence of chronic pain and the incidence of nausea.

CONCLUSIONS

Preoperative use of gabapentin was able to reduce acute and chronic postoperative pain, total morphine consumption and the occurrence of nausea following breast cancer surgery. Further studies should determine the optimal dose of gabapentin for pain control after breast cancer surgery.

Comparison of apatinib and capecitabine (Xeloda) with capecitabine (Xeloda) in advanced triple-negative breast cancer as third-line therapy: A retrospective study

The treatment of advanced triple-negative breast cancer, which failed in first-line or second-line therapy, is a significant challenge. We conducted this retrospective study to explore the efficacy and safety of apatinib and capecitabine as the third-line treatment for advanced triple-negative breast cancer.This retrospective study involved 44 advanced triple-negative breast cancer patients who failed in first-line or second-line therapy in Tangshan People's Hospital from January 2016 to February 2017. Twenty-two patients received apatinib and capecitabine, while 22 patients were treated with capecitabine monotherapy as third-line therapy. The progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and adverse events were compared between 2 groups.The apatinib and capecitabine group exhibited a higher PFS than capecitabine group (P = .001). Meanwhile, ORR and DCR in apatinib and capecitabine group were better than in capecitabine group (P = .042; .016). The 2 groups showed no significant difference in adverse events except degree I-II bleeding (P = .021). Both the apatinib and capecitabine and the capecitabine regimens revealed good tolerability.The apatinib and capecitabine regimen can achieve a better efficacy and similar serious adverse events compared with capecitabine regimen as the third-line treatment for advanced triple-negative breast cancer.

Novel folic acid-conjugated doxorubicin loaded β-lactoglobulin nanoparticles induce apoptosis in breast cancer cells

Chemotherapy constitutes the main strategy in management of breast cancer (BC). Lack of specificity and high burden of adverse effects of chemotherapeutic agents remain the most important impediments to successful treatment of BC patients. Folate receptor α (FRα) could be very promising for therapeutic targeting in this type of cancer. In this study, ß-lactoglobulin nanoparticles (BNPs) conjugated with folic acid and loaded with doxorubicin (FDBNPs) were prepared. Various characterization techniques were applied to determine the size, polydispersity and doxorubicin loading of prepared FDBNPs in comparison with doxorubicin-loaded BNPs (DBNPs). The results showed that FDBNPs are 109.77 ± 2.80 nm in diameter with well dispersed and spherical shapes. The biodegradation of FDBNPs in the presence of trypsin enzyme and in PBS at different pH (4 and 7) was spectrophotometrically monitored and the results showed that the FDBNPs with encapsulation efficiency of 68.82%±1.76% could deliver doxorubicin at clinically relevant doses. Effects of DBNPs and FDBNPs against MCF-7 and MDA-MB-231, BC and triple negative BC (TNBC) cell lines, respectively, showed significant inhibition of cell proliferation as well as induction of apoptosis. Based on these findings, FDBNPs with facilitated drug release and targeted doxorubicin delivery capacities could have high therapeutic potential for BC and TNBC.

Syntenin1/MDA-9 (SDCBP) induces immune evasion in triple-negative breast cancer by upregulating PD-L1

PURPOSE

Syntenin1/SDCBP (syndecan binding protein), also known as melanoma differentiation associated gene-9 (MDA-9), is a PDZ domain-containing molecule, which was initially identified as a key oncogene in melanoma. However, the role of syntenin1 in triple-negative breast cancer (TNBC), especially in suppression of antitumour immune response, remains unknown.

METHODS AND RESULTS

One hundred TNBC tissues were obtained after radical resection and used for analysis. High syntenin1 expression was associated with increased tumour size (r = 0.421, P < 0.001), presence of lymph node metastasis (r = 0.221, P = 0.044) and poor overall survival (P = 0.01) and recurrence-free survival (P = 0.007). Syntenin1 overexpression significantly promoted 4T1 tumour growth and lung metastasis in BALB/c mice by affecting CD8⁺ T cells. Western blot and flow cytometry analyses demonstrated that syntenin1 induced CD8⁺ T cell apoptosis in vitro and in vivo through upregulating PD-L1. Western blot demonstrated that syntenin1 upregulated PD-L1 expression by inducing Tyr705 stat3 phosphorylation, which was further confirmed by stat3 inhibition study. The correlation between syntenin1 and PD-L1 was further confirmed using tumour tissues derived from patients with TNBC (r = 0.509, P < 0.001). Efficacy studies indicated that 4T1-scramble tumour benefitted from anti-PD-L1 therapy (P < 0.001); however, 4T1-syntenin1-KD demonstrated no response to anti-PD-L1 treatment (P = 0.076).

CONCLUSIONS

Syntenin1 exhibits a profound function in mediating T cells apoptosis by upregulating PD-L1 and thus could be used as a prognostic biomarker of TNBC. Tumoural syntenin1 expression corelated with anti-PD-L1 treatment efficacy. Targeting syntenin1-mediated T-cell suppression could be a potential strategy for improving the prognosis of patients with TNBC.

Remotely Phototriggered, Transferrin-Targeted Polymeric Nanoparticles for the Treatment of Breast Cancer

Triple-negative breast cancer (TNBC) has the worst prognosis among all subtypes of breast cancer. Currently, no targeted treatment has been approved for TNBC. The goal of this study was to design a remotely triggered, targeted therapy for TNBC using polymeric nanoparticles and light. Active targeting of TNBC was achieved by conjugating the nanoparticles to a peptide (hTf) that binds to the transferrin receptor, which is overexpressed in TNBC. Photodynamic therapy (PDT) was explored for TNBC treatment by remotely triggering benzoporphyrin derivative monoacid (BPD), a photosensitizer, using near-infrared light. In this study, we investigated the use of actively targeting polymeric nanoparticles for PDT against TNBC using in vitro imaging and cytotoxicity studies. Fluorescence imaging confirmed that the BPD-loaded nanoparticles showed greater fluorescence in TNBC cells compared to free BPD, but more importantly, actively targeted nanoparticles displayed stronger fluorescence compared to passively targeted nanoparticles. Moreover, fluorescence imaging following competition with empty targeted nanoparticles validated the specificity of the targeted nanoparticles for TNBC cells. The PDT killing results were in line with the fluorescence imaging results, where actively targeting nanoparticles exhibited the highest phototriggered cytotoxicity in TNBC cells, making them an attractive nanoplatform for TNBC treatment.

Chemotherapeutic agents for the treatment of metastatic breast cancer: An update

Breast cancer is the second greatest cause of death among women worldwide; it comprises a group of heterogeneous diseases that evolves due to uncontrolled cellular growth and differentiation and the loss of normal programmed cell death. There are different molecular sub-types of breast cancer; therefore, various options are selected for treatment of different forms of metastatic breast cancer. However, the use of chemotherapeutic drugs is usually accompanied by deleterious side effects and the development of drug resistance when applied for a longer period. This review offers a classification of these chemotherapeutic agents according to their modes of action and therefore improves the understanding of molecular targets that are affected during treatment. Overall, it will allow the clinician to identify more specific targets to increase the effectiveness of a drug and to reduce general toxicity, resistance and other side effects.

SOCS1 is associated with clinical progression and acts as an oncogenic role in triple-negative breast cancer

Suppressors of cytokine signaling 1 (SOCS1) is a member of SOCS family and acts as negative regulators of cytokine signaling by direct inhibition of receptor-associated janus kinases. The clinical significance and biological function of SOCS1 in variant tumor tissues and at variant tumor stages is still controversial. The aim of our study is to confirm the expression status of SOCS1 in triple-negative breast cancer (TNBC) tissues and cell lines, and explore the clinical value and biological function of SOCS1 in TNBC. In microarray data sets (GDS2250 and GDS817), we observed SOCS1 was overexpressed in TNBC tissues and cell line compared with normal mammary tissues and mammary epithelial cell line, or non-TNBC tissues and cell line. Furthermore, SOCS1 mRNA and protein overexpression were confirmed in TNBC tissues and cell lines compared with normal mammary tissues and mammary epithelial cell lines or non-TNBC tissues and cell lines. SOCS1 protein overexpression was obviously associated with advanced clinical stage, large tumor size, more lymph node metastasis, present distant metastasis, and malign histological grade. Downregulation of SOCS1 expression suppressed TNBC cells proliferation and promoted cell apoptosis. In conclusion, SOCS1 is associated with clinical progression in TNBC patients and acts as an oncogenic role in regulating TNBC cells proliferation and apoptosis. © 2018 IUBMB Life, 70(4):320-327, 2018.

Receptors for Insulin-Like Growth Factor-2 and Androgens as Therapeutic Targets in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) occurs in 10-15% of all breast cancer patients, yet it accounts for about half of all breast cancer deaths. There is an urgent need to identify new antitumor targets to provide additional treatment options for patients afflicted with this aggressive disease. Preclinical evidence suggests a critical role for insulin-like growth factor-2 (IGF2) and androgen receptor (AR) in regulating TNBC progression. To advance this work, a panel of TNBC cell lines was investigated with all cell lines showing significant expression of IGF2. Treatment with IGF2 stimulated cell proliferation in vitro (p < 0.05). Importantly, combination treatments with IGF1R inhibitors BMS-754807 and NVP-AEW541 elicited significant inhibition of TNBC cell proliferation (p < 0.001). Based on Annexin-V binding assays, BMS-754807, NVP-AEW541 and enzalutamide induced TNBC cell death (p < 0.005). Additionally, combination of enzalutamide with BMS-754807 or NVP-AEW541 exerted significant reductions in TNBC proliferation even in cells with low AR expression (p < 0.001). Notably, NVP-AEW541 and BMS-754807 reduced AR levels in BT549 TNBC cells. These results provide evidence that IGF2 promotes TNBC cell viability and proliferation, while inhibition of IGF1R/IR and AR pathways contribute to blockade of TNBC proliferation and promotion of apoptosis in vitro.