Chemotherapy options for patients suffering from heavily pretreated metastatic breast cancer

Baseline interleukin-6 is a prognostic factor for patients with metastatic breast cancer treated with eribulin

PURPOSE

Eribulin is a unique anti-cancer drug which can improve overall survival (OS) of patients with metastatic breast cancer (MBC), probably by modulating the tumor immune microenvironment. The aim of this study was to investigate the clinical significance of serum levels of immune-related and inflammatory cytokines in patients treated with eribulin. Furthermore, we investigated the association between cytokines and immune cells, such as myeloid-derived suppressor cells (MDSCs) and cytotoxic and regulatory T cells, to explore how these cytokines might affect the immune microenvironment.

METHODS

Sixty-eight patients with MBC treated with eribulin were recruited for this retrospective study. The relationship of cytokines, including interleukin (IL)-6, to progression-free survival and OS was examined. CD4+ and CD8+ lymphocyte, MDSCs and regulatory T cell levels were determined in the blood by flow cytometry analysis.

RESULTS

In our cohort, patients with high IL-6 at baseline had shorter progression-free survival and OS compared with those with low IL-6 (p = 0.0017 and p = 0.0012, respectively). Univariable and multivariable analyses revealed that baseline IL-6 was an independent prognostic factor for OS (p = 0.0058). Importantly, CD8+ lymphocytes were significantly lower and MDSCs were significantly higher in patients with high IL-6, compared to those with low IL-6.

CONCLUSION

Baseline IL-6 is an important prognostic factor in patients with MBC treated with eribulin. Our results show that high IL-6 is associated with higher levels of MDSCs which suppress anti-tumor immunity, such as CD8+ cells. It appears that eribulin is not particularly effective in patients with high IL-6 due to a poor tumor immune microenvironment.

Differential Cytotoxicity of Curcumin-Loaded Micelles on Human Tumor and Stromal Cells

Although curcumin in the form of nanoparticles has been demonstrated as a potential anti-tumor compound, the impact of curcumin and nanocurcumin in vitro on normal cells and in vivo in animal models is largely unknown. This study evaluated the toxicity of curcumin-loaded micelles in vitro and in vivo on several tumor cell lines, primary stromal cells, and zebrafish embryos. Breast tumor cell line (MCF7) and stromal cells (human umbilical cord vein endothelial cells, human fibroblasts, and human umbilical cord-derived mesenchymal stem cells) were used in this study. A zebrafish embryotoxicity (FET) assay was conducted following the Organisation for Economic Co-operation and Development (OECD) Test 236. Compared to free curcumin, curcumin PM showed higher cytotoxicity to MCF7 cells in both monolayer culture and multicellular tumor spheroids. The curcumin-loaded micelles efficiently penetrated the MCF7 spheroids and induced apoptosis. The nanocurcumin reduced the viability and disturbed the function of stromal cells by suppressing cell migration and tube formation. The micelles demonstrated toxicity to the development of zebrafish embryos. Curcumin-loaded micelles demonstrated toxicity to both tumor and normal primary stromal cells and zebrafish embryos, indicating that the use of nanocurcumin in cancer treatment should be carefully investigated and controlled.

An update on the currently available and future chemotherapy for treating bone metastases in breast cancer patients

INTRODUCTION

Bone metastases in breast cancer patients are a common clinical problem. Many factors influence the treatment decision, including tumor characteristics, previous treatment and tumor burden in the treatment of metastatic breast cancer.

AREAS COVERED

This present review summarizes the new treatment strategies and the chemotherapeutic agents currently available in the management of metastatic breast cancer with bone metastases.

EXPERT OPINION

Patients with bone metastases more often have hormone receptor-positive tumours. Although new treatment agents for metastatic breast cancer have been investigated, endocrine therapy is still considered as the treatment of choice for patients with bone metastases although chemotherapy still has an important place. In recent years, new chemotherapeutic agents such as etirinotecan and nab-paclitaxel have been established though there are few studies that have looked at particular types of metastases. In the last decade, therapies for bone metastasis resistant to endocrine therapy have predominantly focused on radiotherapy, surgical resection, chemotherapy, bone-targeting radiopharmaceuticals and targeted therapeutics. New targeted agents include: Src inhibitors, cathepsin K inhibitors, CXCR4 inhibitors, TGF-B blockade and integrin antagonists while drug delivery systems for chemotherapy have also been developed. These new treatment options could be future treatment options for bone metastatic disease if early promising results are confirmed by clinical trials.

Long-term treatment with eribulin in heavily pretreated women with metastatic breast cancer: a case series

During the last decades, much effort has been made to develop and test treatments for advanced/metastatic breast cancer (MBC) able to prolong survival and improve patients' quality of life. In this regard, eribulin represents one of the most recent and interesting discoveries. This tubulin-targeting chemotherapy demonstrated a survival benefit in MBC women who progressed after at least two prior lines of chemotherapy for the treatment of metastatic disease (prior therapies should have included an anthracycline and a taxane, in either adjuvant or metastatic setting). Here, we described five cases of heavily pretreated MBC patients who experienced long-lasting control of disease with eribulin.

Eribulin across multiple lines of chemotherapy: a retrospective study on quality of life and efficacy in metastatic breast cancer patients

This study evaluates efficacy, tolerability and health-related quality of life of eribulin in patients with metastatic breast cancer. Predictive and/or prognostic factors of outcome were also analyzed. Among 44 women receiving eribulin mesylate, one patient had a complete response, 22.7% a partial response and 25% a stable disease. Median overall survival and median progression-free survival were 11.8 and 4.5 months, respectively. Treatment was well tolerated; the most frequent adverse events were neutropenia (52%), leukopenia (50%), fatigue (38%) and alopecia (40%). No significant reductions of health-related quality of life parameters were observed. Disease control during previous chemotherapy lines was related with better outcome with eribulin. In conclusion, eribulin treatment should be considered in a multiple chemotherapy lines strategy in metastatic breast cancer.

Eribulin efficacy based on type of metastatic site: a real-life study in heavily pretreated metastatic breast cancer

AIM

The halichondrin B analog, eribulin, exerts an anticancer effect, as reported by several clinical and real-life studies on metastatic breast cancer patients. Here, we evaluated efficacy and safety of eribulin, focusing on response to treatment per metastasis type.

PATIENTS & METHODS

This monocentric, real-life study was conducted on 31 heavily pretreated patients with metastatic breast cancer.

RESULTS

The median progression-free survival and overall survival were 2.0 and 5.5 months, respectively. All patients (12.9%) responding to eribulin were treated in fourth-line setting. Considering response per metastasis type, bone lesions (13.6%) responded more frequently than other metastases to eribulin.

CONCLUSION

Eribulin exhibited a good overall response rate, with the highest response observed for bone metastases.

Randomized Phase II Study of Ramucirumab or Icrucumab in Combination with Capecitabine in Patients with Previously Treated Locally Advanced or Metastatic Breast Cancer

BACKGROUND

Icrucumab (ICR) and ramucirumab (RAM) bind vascular endothelial growth factor (VEGF) receptors 1 and 2 (VEGFR-1 and -2), respectively. This open-label, randomized phase II study evaluated their efficacy and safety in combination with capecitabine (CAP) in patients with previously treated unresectable, locally advanced or metastatic breast cancer.

METHODS

Patients were randomly assigned (1:1:1) to receive CAP (1,000 mg/m2 orally twice daily, days 1-14) alone or in combination with RAM (10 mg/kg intravenously [IV], days 1 and 8) (RAM + CAP) or ICR (12 mg/kg IV, days 1 and 8) (ICR + CAP) every 21 days. The primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), tumor response, safety, and pharmacokinetics.

RESULTS

Of 153 patients randomized, 150 received treatment. Median PFS (95% confidence interval) was 22.1 (12.1-36.1) weeks on RAM + CAP, 7.3 (6.3-13.0) weeks on ICR + CAP, and 19.0 (12.1-24.3) weeks on CAP (hazard ratios [HRs]: 0.691, p = .1315, RAM + CAP versus CAP; 1.480, p = .0851, ICR + CAP versus CAP). Median OS was 67.4 weeks on RAM + CAP, 62.1 weeks on ICR + CAP, and 71.6 weeks on CAP (HRs: 1.833, p = .0283, RAM + CAP versus CAP; 1.468, p = .1550, ICR + CAP versus CAP). There was no statistically significant difference in PFS or OS between either combination arm and CAP. Treatment-related adverse events more frequent (by ≥10%) on RAM + CAP than on CAP were constipation, decreased appetite, headache, epistaxis, and hypertension. Those more frequent (by ≥10%) on ICR + CAP than CAP were anemia, increased lacrimation, periorbital edema, nausea, vomiting, peripheral edema, facial edema, dehydration, and dyspnea.

CONCLUSION

Combining RAM or ICR with CAP did not improve PFS in the targeted study population. The Oncologist 2017;22:245-254 IMPLICATIONS FOR PRACTICE: Icrucumab and ramucirumab are recombinant human IgG1 monoclonal antibodies that bind vascular endothelial growth factor (VEGF) receptors 1 and 2 (VEGFR-1 and -2), respectively. VEGFR-1 activation on endothelial and tumor cell surfaces increases tumor vascularization and growth and supports tumor growth via multiple mechanisms, including contributions to angiogenesis and direct promotion of cancer cell proliferation. Strong preclinical and clinical evidence suggests key roles for VEGF and angiogenesis in breast cancer growth, invasion, and metastasis. This randomized phase II study evaluated the efficacy and safety of each antibody in combination with capecitabine in patients with previously treated unresectable, locally advanced or metastatic breast cancer.

Efficacy and safety of doublet versus single agent as salvage treatment for metastatic breast cancer pretreated with anthracyclines and taxanes: a systematic review and meta-analysis

AIM

To perform a systematic review and meta-analysis of randomized controlled trials to compare the efficacy and safety of doublet versus single agent as salvage treatment for pretreated metastatic breast cancer.

METHODS

A comprehensive literature search was performed to identify relevant randomized controlled trials (RCTs). All clinical studies were independently identified by two authors for inclusion. Demographic data, treatment regimens, objective response rate (ORR), and progression-free survival (PFS) and overall survival (OS) were extracted and analyzed using Comprehensive MetaAnalysis software (Version 2.0).

RESULTS

Thirteen RCTs involving 4878 pretreated metastatic breast cancer patients were ultimately identified. The pooled results demonstrated that doublet combination therapy significantly improved ORR (RR 1.13, 95% CI: 1.01-1.27, p < .001) and PFS (hazard ration [HR] 0.83, 95% CI: 0.73-0.96, p = .011), but not OS (HR 0.93, 95% CI: 0.86-1.01, p = .065). Similar results were observed in sub-group analysis according to treatment regimens. Additionally, more incidences of grade 3 or 4 myelosuppression toxicities nausea and fatigue were observed in doublet combination therapy.

CONCLUSIONS

In comparison with a single agent alone, doublet combination therapy as salvage treatment for pretreated metastatic breast cancer patients significantly improves ORR and PFS, but not OS. Further studies are recommended to identify patients who will most likely benefit from the appropriate doublet combination therapy.

A meta-analysis of combination therapy versus single-agent therapy in anthracycline- and taxane-pretreated metastatic breast cancer: results from nine randomized Phase III trials

Nowadays, the philosophy of treating metastatic breast cancer (MBC) is slowly evolving. Especially for the anthracycline- and taxane-pretreated MBC patients, no standard therapy exists in this setting. Whether to choose doublet agents or single agent as salvage treatment remains fiercely debated. Thus, we conducted a meta-analysis to resolve this problem. Databases including PubMed, EMBASE, and Cochrane library were searched for Phase III randomized clinical trials (published before August 2015) comparing the efficacy and adverse effects between the combination therapy and single-agent therapy in anthracycline- and taxane-pretreated MBC patients. The primary end point was the overall survival (OS), and the secondary end points were the progression-free survival (PFS), overall response rate (ORR), and grade 3 or 4 toxicities. The pooled hazard ratio (HR) and pooled risk ratio (RR) were used to evaluate the efficacy. Analyses were also performed to estimate the side effects and safety of both groups. In all, nine eligible randomized clinical trials were included in this meta-analysis. Improvements were proven in the doublet agents group on OS (HR 0.90, 95% confidence interval [CI] 0.84–0.96, P=0.002), PFS (HR 0.81, 95% CI 0.76–0.88, P<0.001), and ORR (RR 1.72, 95% CI 1.34–2.21, P<0.001). Notably, subgroup analysis failed to favor the targeted agent-based combination in terms of OS (HR 1.08, 95% CI 0.89–1.31, P=0.365), PFS (HR 1.09, 95% CI 0.88–1.35, P=0.433), and ORR (RR 1.60, 95% CI 0.69–3.71, P=0.278) compared with single agent. In addition, although more hematological and gastrointestinal toxicities were observed in the doublet agents group, they were acceptable and manageable. Taken together, when compared with single-agent therapy, doublet agents should be considered a treatment option because of the superior efficacy and the manageable safety profile for the prior anthracycline- and taxane-treated MBC patients.

MiR-181b promotes chemoresistance in breast cancer by regulating Bim expression

MicroRNAs are emerging as critical regulators of the initiation and progression of multiple types of human cancers, including breast cancer. In the present study, the expression of miR-181b in breast cancer patient serum and breast cancer cell lines was evaluated. It was demonstrated that the miR-181b level was significantly upregulated in patient serum and breast cancer cell lines compared with that in normal controls. The results of in vitro 3H thymidine incorporation and Transwell migration assay indicated that miR-181b overexpression markedly promoted the proliferation and metastasis of breast cancer cells. These data suggest that miR-181b is a tumor promoter in breast cancer. Furthermore, miR-181b expression was found to be upregulated in doxorubicin (DOX)-resistant T-47D cells (T-47D-R) compared with that in the parental T-47D cells, and upregulation of miR-181b expression decreased the anticancer effect of DOX in the T-47D cells. Mechanistic studies demonstrated that the Bim gene, an essential initiator of apoptosis, was inhibited by miR-181b overexpression. We observed that knockdown of miR-181b by its specific inhibitors significantly re-sensitized the T-47D-R cells to the cytotoxicity of DOX. Importantly, we demonstrated that miR-181b inhibitors increased the level of Bim in the T-47D-R cells, resulting in the loss of mitochondrial membrane potential (MMP) and the activation of caspases caused by DOX. In summary, the results of the present study suggest that miR-181b functions as an oncogene during breast cancer development, and the miR-181b/Bim pathway may be a novel target used to overcome the chemoresistance in breast cancer.

MiR-944 functions as a novel oncogene and regulates the chemoresistance in breast cancer

MircroRNAs are emerging as critical regulators in carcinogenesis and chemoresistance in multiple cancer types. In this study, we observed that the miR-944 level was upregulated in breast cancer patients' serum and tumor tissues, suggesting that miR-944 is a tumor promoter in breast cancer. To investigate the role of miR-944, we performed gain- and loss-of-function experiments in vitro. We then demonstrated that miR-944 promotes cell proliferation and tumor metastasis in breast cancer cell lines. Furthermore, we indicated that miR-944 is associated with cisplatin resistance by targeting BNIP3. Knockdown of the miR-944 by specific inhibitors significantly increased the cytotoxicity of cisplatin in cisplatin-resistant MCF-7 cells (MCF-7/R). Importantly, we found that the sensitization of miR-944 inhibitors to cisplatin cytotoxicity was abolished by BNIP3 siRNA which decreased the expression of BNIP3 gene. Finally, we demonstrated that miR-944 inhibitors promoted the loss of mitochondrial membrane potential (MMP) caused by cisplatin in MCF-7/R cells, resulting in the release of mitochondria-derived apoptogenic proteins into cytoplasm, and then, the caspase-3 was activated. In summary, our study showed that miR-944 functions as a novel oncogene and regulates the cisplatin resistance in breast cancer. The miR-944-BNIP3-MMP-caspase-3 pathway might be a novel target for the chemotherapy of breast cancer.