Related Experiment Video
Updated: Mar 9, 2026
High-Throughput Dissociation and Orthotopic Implantation of Breast Cancer Patient-Derived Xenografts
Published on: December 20, 2024
Integrated RNA-seq and DNase-seq analyses identify phenotype-specific BMP4 signaling in breast cancer
M Ampuja1,2, T Rantapero3, A Rodriguez-Martinez3,4
1BioMediTech, University of Tampere, Tampere, Finland. minna.ampuja@uta.fi.
Background:
Bone morphogenetic protein 4 (BMP4) plays an important role in cancer pathogenesis. In breast cancer, it reduces proliferation and increases migration in a cell line-dependent manner. To characterize the transcriptional mediators of these phenotypes, we performed RNA-seq and DNase-seq analyses after BMP4 treatment in MDA-MB-231 and T-47D breast cancer cells that respond to BMP4 with enhanced migration and decreased cell growth, respectively.
Results:
The RNA-seq data revealed gene expression changes that were consistent with the in vitro phenotypes of the cell lines, particularly in MDA-MB-231, where migration-related processes were enriched. These results were confirmed when enrichment of BMP4-induced open chromatin regions was analyzed. Interestingly, the chromatin in transcription start sites of differentially expressed genes was already open in unstimulated cells, thus enabling rapid recruitment of transcription factors to the promoters as a response to stimulation. Further analysis and functional validation identified MBD2, CBFB, and HIF1A as downstream regulators of BMP4 signaling. Silencing of these transcription factors revealed that MBD2 was a consistent activator of target genes in both cell lines, CBFB an activator in cells with reduced proliferation phenotype, and HIF1A a repressor in cells with induced migration phenotype.
Conclusions:
Integrating RNA-seq and DNase-seq data showed that the phenotypic responses to BMP4 in breast cancer cell lines are reflected in transcriptomic and chromatin levels. We identified and experimentally validated downstream regulators of BMP4 signaling that relate to the different in vitro phenotypes and thus demonstrate that the downstream BMP4 response is regulated in a cell type-specific manner.
Insights
Bone morphogenetic protein 4 (BMP4) influences breast cancer cell behavior differently depending on the cell type. Researchers identified key regulators like MBD2, CBFB, and HIF1A, revealing cell-specific responses to BMP4 signaling.
Area of Science:
- Molecular Biology
- Cancer Research
- Genomics
Background:
- Bone morphogenetic protein 4 (BMP4) is implicated in cancer development.
- In breast cancer, BMP4 affects cell proliferation and migration in a cell line-specific manner.
- Understanding BMP4's transcriptional mediators is crucial for characterizing its role in breast cancer.
Purpose of the Study:
- To investigate the transcriptional mediators of BMP4-induced phenotypes in breast cancer.
- To analyze gene expression and chromatin accessibility changes in response to BMP4.
- To identify and validate downstream regulators of BMP4 signaling in different breast cancer cell lines.
Main Methods:
- RNA sequencing (RNA-seq) to analyze gene expression.
- DNase sequencing (DNase-seq) to assess chromatin accessibility.
- Functional validation of identified downstream regulators (MBD2, CBFB, HIF1A) through gene silencing.
Main Results:
- BMP4 treatment altered gene expression and chromatin accessibility in MDA-MB-231 and T-47D breast cancer cells.
- Migration-related processes were enriched in MDA-MB-231 cells, while proliferation was reduced in T-47D cells.
- MBD2, CBFB, and HIF1A were identified as key downstream regulators, acting as activators or repressors in a cell-type-specific manner.
Conclusions:
- BMP4's phenotypic effects in breast cancer are mirrored at transcriptomic and chromatin levels.
- Downstream regulators of BMP4 signaling were identified and validated.
- BMP4 signaling demonstrates cell type-specific regulation in breast cancer.
