An ets2-driven transcriptional program in tumor-associated macrophages promotes tumor metastasis

Area of Science:

• Oncology
• Immunology
• Molecular Biology

Background:

• Tumor-associated macrophages (TAMs) play a critical role in breast cancer metastasis.
• The specific genes and pathways regulated by TAMs in metastasis are not fully understood.
• Ets2 is a transcription factor involved in macrophage function and inflammation.

Purpose of the Study:

• To investigate the role of Ets2 in TAMs during breast cancer growth and metastasis.
• To identify the downstream targets and mechanisms by which Ets2 influences metastasis.

Main Methods:

• Conditional deletion of Ets2 in TAMs in mouse models of breast cancer.
• Gene expression profiling and chromatin immunoprecipitation assays on isolated TAMs.
• Analysis of angiogenesis, tumor growth, and lung metastasis.
• Identification and validation of an Ets2-TAM expression signature in human breast cancer data.

Main Results:

• Ets2 deletion in TAMs significantly reduced lung metastasis frequency and size in multiple mouse models.
• Ets2 was found to repress a gene program including angiogenesis inhibitors.
• Ablation of Ets2 in TAMs led to decreased angiogenesis and tumor growth.
• An Ets2-TAM signature of 133 genes predicted patient survival in human breast cancer datasets.

Conclusions:

• Ets2 is a key driver of a transcriptional program in TAMs that promotes breast cancer lung metastasis.
• Ets2 regulates angiogenesis and tumor growth through its effects on TAMs.
• The identified Ets2-TAM signature serves as a potential biomarker for breast cancer prognosis.