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

Boolean modeling of breast cancer signaling pathways uncovers mechanisms of drug synergy

Breast cancer is one of the most common types of cancer in females. While drug combinations have shown potential in breast cancer treatments, identifying new effective drug pairs is challenging due to the vast number of possible combinations among available compounds. Efforts have been made to accelerate the process with in silico predictions. Here, we developed a Boolean model of signaling pathways in breast cancer. The model was tailored to represent five breast cancer cell lines by integrating information about cell-line specific mutations, gene expression, and drug treatments. The models reproduced cell-line specific protein activities and drug-response behaviors in agreement with experimental data. Next, we proposed a calculation of protein synergy scores (PSSs), determining the effect of drug combinations on individual proteins' activities. The PSSs of selected proteins were used to investigate the synergistic effects of 150 drug combinations across five cancer cell lines. The comparison of the highest single agent (HSA) synergy scores between experiments and model predictions from the MDA-MB-231 cell line achieved the highest Pearson's correlation coefficient of 0.58 with a great balance among the classification metrics (AUC = 0.74, sensitivity = 0.63, and specificity = 0.64). Finally, we clustered drug pairs into groups based on the selected PSSs to gain further insights into the mechanisms underlying the observed synergistic effects of drug pairs. Clustering analysis allowed us to identify distinct patterns in the protein activities that correspond to five different modes of synergy: 1) synergistic activation of FADD and BID (extrinsic apoptosis pathway), 2) synergistic inhibition of BCL2 (intrinsic apoptosis pathway), 3) synergistic inhibition of MTORC1, 4) synergistic inhibition of ESR1, and 5) synergistic inhibition of CYCLIN D. Our approach offers a mechanistic understanding of the efficacy of drug combinations and provides direction for selecting potential drug pairs worthy of further laboratory investigation.

MEK1 Inhibitor Combined with Irradiation Reduces Migration of Breast Cancer Cells Including miR-221 and ZEB1 EMT Marker Expression

Simple Summary

Combined chemotherapy and radiotherapy are an effective treatment for invasive breast cancer. However, some studies suggest that such interventions may increase the risk of metastasis. Cell metastatic behavior is highly dependent on RAS-RAF-MEK pathway and its downstream target activation, including miR-221 overexpression and epithelial-to-mesenchymal transition (EMT). By using MEK1 inhibitor (TAK-733) in combination with radiation therapy for breast cancer cells, significant decrease in migration capacity, including reduction of miR-221 and EMT (ZEB1) marker expression was observed. miR-221 holds great potential as therapeutic biomarker and target for new drug developments, however more insight into efficiency of miR-221 inhibition needs to be followed in the future.

Abstract

The miR-221 expression is dependent on the oncogenic RAS-RAF-MEK pathway activation and influences epithelial-to-mesenchymal transition (EMT). The Cancer Genome Atlas (TCGA) database analysis showed high gene significance for ZEB1 with EMT module analysis and miR-221 overexpression within the triple-negative breast cancer (TNBC) and HER2+ subgroups when compared to luminal A/B subgroups. EMT marker expression analysis after MEK1 (TAK-733) inhibitor treatment and irradiation was combined with miR-221 and ZEB1 expression analysis. The interaction of miR-221 overexpression with irradiation and its influence on migration, proliferation, colony formation and subsequent EMT target activation were investigated. The results revealed that MEK1 inhibitor treatment combined with irradiation could decrease the migratory potential of breast cancer cells including reduction of miR-221 and corresponding downstream ZEB1 (EMT) marker expression. The clonogenic survival assays revealed that miR-221 overexpressing SKBR3 cells were more radioresistant when compared to the control. Remarkably, the effect of miR-221 overexpression on migration in highly proliferative and highly HER2-positive SKBR3 cells remained constant even upon 8 Gy irradiation. Further, in naturally miR-221-overexpressing MDA-MB-231 cells, the proliferation and migration significantly decrease after miR-221 knockdown. This leads to the assumption that radiation alone is not reducing migration capacity of miR-221-overexpressing cells and that additional factors play an important role in this context. The miR-221/ZEB1 activity is efficiently targeted upon MEK1 inhibitor (TAK-733) treatment and when combined with irradiation treatment, significant reduction in migration of breast cancer cells was shown.

Multicentre, phase II study of eribulin in combination with S-1 in patients with advanced breast cancer

Background

We previously reported the synergistic effect of S-1 and eribulin in preclinical models. In addition, our phase I study revealed the recommended dose for the phase II study of the combination therapy in advanced breast cancer (ABC) patients pre-treated with anthracycline and taxane. Our current study reports on the efficacy and safety of the combined use of eribulin and S-1 in patients with ABC and poor prognosis.

Methods

Patients with breast cancer who received prior anthracycline- and/or taxane-based therapy were assigned to receive a combination therapy of eribulin (1.4 mg/m² on days 1 and 8, every 21 days) and S-1 (65 mg/m², on days 1 to 14, every 21 days) for advanced/metastatic disease. All patients had at least one clinicopathological factor such as being oestrogen receptor negative, Human Epidermal Growth Factor Receptor 2 (HER2) receptor negative, presence of visceral involvement, presence of three or more metastatic sites, or having a disease-free interval shorter than 2 years. The primary endpoint was the independent-reviewer assessed objective response rate (ORR). Secondary endpoints were clinical benefit rate, disease control rate, progression-free survival (PFS), and overall survival (OS).

Results

This study enrolled 33 patients. Confirmed ORR was 33.3% (95% CI: 17.3 to 52.8). Median PFS was 7.5 months (95% CI: 4.0 to 14.3). Median OS time was not reached during the current experimental periods. The most common grade 3/4 adverse event was neutropenia (68.8%).

Conclusions

The combination of eribulin and S-1 is safe and effective for treatment in patients with ABC and poor prognosis.

Trial registration

Current Controlled Trials UMIN000015049, date of registration: September 5th 2014.

A comparison of fulvestrant plus a targeted agent with fulvestrant alone in hormone receptor-positive advanced breast cancer that progressed on prior endocrine therapy: a meta-analysis

Fulvestrant is recommended for the hormone receptor-positive metastatic breast cancer (MBC) patients progressed during or after prior endocrine therapy. Notably, recent evidence has also demonstrated that adding a targeted agent to fulvestrant conferred a significantly clinical benefit in these patients. Since these results were inconsistent among the studies, this meta-analysis herein was conducted to compare the efficacy and toxicities of the fulvestrant-based combination therapy with fulvestrant monotherapy. Thus, a systemic research was performed in PubMed, Embase, and Cochrane library to identify relevant Phase II or Phase III randomized controlled trials. The progression-free survival (PFS), overall response rate (ORR), and toxicities were evaluated. And HR, risk ratio (RR), and their 95% CIs were employed to complete the pooled analyses. In total, 13 studies with 3,910-hour positive MBC patients progressed on prior endocrine therapy were included in our meta-analysis. Improvements of doublet-agents group were proven in terms of PFS (HR 0.73, 95% CI =0.63–0.86, P=0.000) and ORR (RR 2.07, 95% CI =1.67–2.58, P=0.000). And the further subgroup analysis also demonstrated that fulvestrant in combination with a cyclin-dependent kinase (CDK4/6) inhibitor or a PI3K/mTOR inhibitor was associated with a superior efficacy (RR 2.72, 95% CI =1.93–3.83, P=0.000 and RR 1.60, 95% CI =1.15–2.23, P=0.005, respectively). However, the efficacy was comparable between the other combination strategies and fulvestrant alone. With respect to the adverse effects, adding a targeted agent to fulvestrant also produced more frequent grade 3/4 toxicities (RR 3.86, 95% CI =2.66–5.61, P=0.000). Taken together, combination of fulvestrant with a targeted agent, especially inhibitors targeting CDK4/6 or PI3K/mTOR pathway, may open a new avenue for more effective therapies in relapse or metastatic hormone receptor-positive breast cancer after prior aromatase inhibitors or tamoxifen treatment. In addition, identifying reliable biomarkers to delineate which subgroup of patients will specially benefit from fulvestrant-based combination therapy is warranted.

Lobaplatin-based regimens outperform cisplatin for metastatic breast cancer after anthracyclines and taxanes treatment

The goal of this study was to assess the antitumor efficacy and safety of lobaplatin-based regimens as the second line of treatment in patients with metastatic breast cancer (MBC) resistant to anthracyclines and taxanes, compared with that of cisplatin-based regimens. During August 2012 to April 2015, 87 patients who received lobaplatin-based regimens or cisplatin-based regimens were included. Medical records of the patients noted that lobaplatin (30 mg/m2) or cisplatin (25 mg/m2), combined with another chemotherapeutic agent such as Gemcitabine (1000 mg/m2) or Vinorelbine (25 mg/m2), was intravenously given to the patients on a basis of twenty-one days as one treatment cycle. All the patients were followed until August 2017. The endpoint of this study was progression-free survival (PFS), overall survival (OS), and estimated objective response rate (RR). Safety and drug tolerability data were also obtained. Lobaplatin-based regimens prolonged PFS compared to cisplatin-based regimens (median 13.2 vs 4.7 months, hazard ratio = 0.37, 95% confidence intervals: 0.21-0.67, P = .0007), while OS was not significantly different between the two groups (hazard ratio = 0.72, 95% confidence intervals: 0.40-1.30, P = .2767), as was objective RR (37.8% vs 33.4%, x 2 = 0.19, P = .6653). Nausea/vomiting and renal injury were more frequent with cisplatin-based regimens. Our results show that lobaplatin-based regimens are superior to cisplatin in terms of efficacy and are better tolerated.

Impact of Anthracyclines on Diabetes Mellitus Development in B-Cell Lymphoma Patients: A Nationwide Population-based Study

BACKGROUND AND OBJECTIVES

Although anthracyclines are effective chemotherapeutic agents for treating B-cell lymphoma, adverse effects, such as bone marrow suppression and cardiotoxicity, limit their clinical application. We assessed whether anthracycline treatment also increases the risk for diabetes mellitus in patients with B-cell lymphoma.

METHODS

Using data obtained from the Taiwanese National Health Insurance Research Database from 2004 to 2011, we compared overall survival and clinical features for B-cell lymphoma patients administered anthracyclines (n = 3147) and those not administered anthracyclines (n = 837). The impact of anthracycline treatment on diabetes risk was further investigated using a Gray's test and multivariate competing-risk regression models in a dose-dependent manner.

RESULTS

Anthracycline administration was associated with a higher incidence of diabetes (HR: 1.75; 95% CI 1.11-2.75; p = 0.0163) after adjustments for age, gender, cumulative dose of prednisolone, and co-morbidities. Cumulative anthracycline doses of 253-400 mg (HR: 2.35; 95% CI 1.41-3.91; p = 0.0010), 401-504 mg (HR: 2.26; 95% CI 1.26-4.05; p = 0.0063), and > 504 mg (HR: 2.29; 95% CI 1.25-4.18; p = 0.0072) increased the incidence density of diabetes in a dose-dependent manner (p = 0.0006). The annual alteration of adapted diabetes complications severity index score was not significantly different between B-cell lymphoma patients with or without anthracycline treatment (p = 0.4924).

CONCLUSION

Anthracycline therapy increases diabetes risk in a dose-dependent manner in B-cell lymphoma patients. Intensive blood glucose monitoring and control should be recommended for B-cell lymphoma patients receiving anthracycline treatment.

Targeting chaperonin containing TCP1 (CCT) as a molecular therapeutic for small cell lung cancer

Identifying new druggable targets is desired to meet the needs for effective cancer treatments. To this end, we previously reported the efficacy of a therapeutic peptide called CT20p that displays selective cytotoxicity through inhibition of a multi-subunit, protein-folding complex called Chaperonin-Containing TCP-1 (CCT). To investigate the role of CCT in cancer progression, we examined protein levels of CCT subunits in liver, prostate, and lung cancer using human tissue microarrays. We found that these cancers expressed higher levels of CCT2 as compared to normal tissues. Small cell lung cancer (SCLC) stood out as having statistically significant difference in CCT2. Higher levels of CCT2 in tumors from lung cancer patients were also associated with decreased survival. Using SCLC cell lines, we observed detectable amounts of CCT subunits and cells were susceptible to killing by CT20p. Treatment with CT20p, delivered to cells using polymeric nanoparticles, was cytotoxic to all SCLC cell lines, decreasing the levels of CCT client proteins like STAT3. In contrast, treatment with a STAT3 inhibitor was effective in one of the SCLC cell lines. While we found that CCT levels could vary in cell lines, normal tissues had low levels of CCT and minimal toxicity to liver or kidney function was observed in mice treated with CT20p. These results indicate that in SCLC, changes in CCT levels could be used as a biomarker for diagnosis and that targeting CCT for inhibition with CT20p is a promising treatment approach for those cancers such as SCLC that currently lack targeted therapeutics.

Randomized Phase II Study Investigating Pazopanib Versus Weekly Paclitaxel in Relapsed or Progressive Urothelial Cancer

Purpose Two previous single-arm trials have drawn conflicting conclusions regarding the activity of pazopanib in urothelial cancers after failure of platinum-based chemotherapy. Patients and Methods This randomized (1:1) open-label phase II trial compared the efficacy of pazopanib 800 mg orally with paclitaxel (80 mg/m2 days 1, 8, and 15 every 28 days) in the second-line setting. The primary end point was overall survival (OS). Results Between August 2012 and October 2014, 131 patients, out of 140 planned, were randomly assigned. The study was terminated early on the recommendation of the independent data monitoring committee because of futility. Final analysis after the preplanned number of deaths (n = 110) occurred after a median follow-up of 18 months. One hundred fifteen deaths had occurred at the final data extract presented here. Median OS was 8.0 months for paclitaxel (80% CI, 6.9 to 9.7 months) and 4.7 months for pazopanib (80% CI, 4.2 to 6.4 months). The hazard ratio (HR) adjusted for baseline stratification factors was 1.28 (80% CI, 0.99 to 1.67; one-sided P = .89). Median progression-free survival was 4.1 months for paclitaxel (80% CI, 3.0 to 5.6 months) and 3.1 months for pazopanib (80% CI, 2.7 to 4.6 months; HR, 1.09; 80% CI, 0.85 to 1.40; one-sided P = .67). Discontinuations for toxicity occurred in 7.8% and 23.1% for paclitaxel and pazopanib, respectively. Conclusion Pazopanib did not have greater efficacy than paclitaxel in the second-line treatment of urothelial cancers. There was a trend toward superior OS for paclitaxel.