Abstract 3971
Background
MammaPrint® (MP) is a 70-gene based prognostic assay that stratifies early-stage breast cancer patients into low and high-risk of relapse. Recently, further stratification of the 70-gene risk results identified extreme low and high-risk subgroups with specific clinical outcomes (Delahaye et al. 2017) and treatment response characteristics (Wolf et al. 2017). However, the biological profiles of these extreme MP subgroups are not fully investigated. In this study, we aim to gain more insight into their biological significance using differentially expression genes (DEGs) analysis.
Methods
We selected 400 samples from the whole MP range and defined 4 subgroups (Ultra high [UH], High risk [HR], Low risk [LR], Ultra low [UL]), for which FFPE microarray full-transcriptome data were available at Agendia. DEGs analysis was performed with limma and subsequent pathway analysis with Enrichr and GOrilla.
Results
Two separate comparative analyses were carried out to unravel biological processes associated with extreme risk subgroups: UL vs. LR and UH vs. HR. We found 101 DEGs (logFC > =0.485 & FDR <0.05) between UL and LR subgroups and 1714 DEGs between UH and HR subgroups. Based on the pathway analysis, our results showed that the UL subgroup was more homogeneous, with enrichment in pathways reflecting low proliferative and metastatic features. This is in line with the favorable long-term outcome characteristic of the UL group. Conversely UH exhibited higher heterogeneity, with the enrichment of more diverse pathways including immune response, cell cycle and proliferation, that could be associated with genomic instability. This would support the recent finding of UH samples being more sensitive to veliparib/carboplatin combination therapy compared to HR samples (Wolf et al. 2017)). Furthermore, clustering approach demonstrated UH and other subgroups as two distinct clusters.
Conclusions
Our preliminary findings give additional insights into the biological processes associated with extreme MP groups, which might open new avenues for therapeutic intervention in breast cancer.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Agendia Inc.
Funding
Agendia Inc.
Disclosure
R. Bhaskaran: Full / Part-time employment: Agendia Inc. C. Griffioen: Full / Part-time employment: Agendia Inc. D. Wehkamp: Full / Part-time employment: Agendia Inc. L. Mittempergher: Full / Part-time employment: Agendia Inc. A.M. Glas: Full / Part-time employment: Agendia Inc.
Resources from the same session
4022 - Ribociclib (RIB) plus letrozole (LET) in male patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor-2–negative (HER2–) advanced breast cancer (ABC) from the CompLEEment-1 trial
Presenter: Mario Campone
Session: Poster Display session 2
Resources:
Abstract
3599 - Comparative effectiveness of palbociclib plus letrozole vs letrozole for metastatic breast cancer in US real-world clinical practices
Presenter: Rachel Layman
Session: Poster Display session 2
Resources:
Abstract
901 - Pharmacokinetics (PK), safety, and efficacy of [fam-] trastuzumab deruxtecan with OATP1B/CYP3A inhibitors in subjects with HER2-expressing advanced solid tumors
Presenter: Yung-Jue Bang
Session: Poster Display session 2
Resources:
Abstract
2777 - A Phase 2 study of abemaciclib in patients (pts) with brain metastases (BM) secondary to non-small cell lung cancer (NSCLC) or melanoma (MEL).
Presenter: Solmaz Sahebjam
Session: Poster Display session 2
Resources:
Abstract
3980 - Ribociclib (RIB) + letrozole (LET) in patients (pts) with visceral metastases (VM) or bone-only metastases (BOM) in hormone receptor-positive (HR+), human epidermal growth factor receptor-2–negative (HER2–) advanced breast cancer (ABC): Subgroup analysis from the CompLEEment-1 trial
Presenter: Michelino De Laurentiis
Session: Poster Display session 2
Resources:
Abstract
4024 - Ribociclib (RIB) + letrozole (LET) in patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor-2–negative (HER2–) advanced breast cancer (ABC) and central nervous system (CNS) metastases: Subgroup analysis from the phase 3b CompLEEment-1 trial
Presenter: Paul Cottu
Session: Poster Display session 2
Resources:
Abstract
2151 - Clinical outcome and toxicity data in patients with advanced breast cancer treated with cyclin-dependent kinase 4/6 (CDK4/6) inhibitors combined with endocrine therapy in a real-world clinical setting.
Presenter: Elena Fountzilas
Session: Poster Display session 2
Resources:
Abstract
3994 - Safety and efficacy of Ribociclib (RIBO) + letrozole (LET) in patients (pts) with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) advanced breast cancer (ABC): Interim results from the Italian cohort of the CompLEEment-1 (C-1) study.
Presenter: Michele De Laurentiis
Session: Poster Display session 2
Resources:
Abstract
1370 - Interim Results From CompLEEment-1 (A Phase 3b Study of Ribociclib and Letrozole as First-Line Therapy for Advanced Breast Cancer in an Expanded Population): Spanish cohort results
Presenter: Javier Salvador
Session: Poster Display session 2
Resources:
Abstract
1109 - First Canadian Interim Analysis from the Phase IIIb CompLEEment-1 Ribociclib + Letrozole HR+ HER2- Advanced Breast Cancer Trial
Presenter: Cristiano Ferrario
Session: Poster Display session 2
Resources:
Abstract