Myeloid cell trafficking and tumor angiogenesis
Michael C Schmid1, Judith A Varner
1Moores UCSD Cancer Center, University of California, San Diego, 3855 Health Sciences Drive, La Jolla, CA 92093-0912, USA.
Cancer Letters
|October 20, 2006
Summary
Monocytes from bone marrow are key regulators of tumor neovascularization, promoting tumor growth and metastasis. Targeting these myeloid cells offers a promising new cancer therapy strategy.
Area of Science:
- Oncology
- Immunology
- Cell Biology
Background:
- Tumor growth and metastasis are critically dependent on neovascularization.
- Monocytes, myeloid lineage cells, are increasingly recognized as regulators of tumor neovascularization.
- Tumors attract and infiltrate significant numbers of monocytes.
Purpose of the Study:
- To investigate the role of monocytes in tumor neovascularization.
- To explore the mechanisms by which monocytes contribute to blood vessel formation in tumors.
- To assess the therapeutic potential of modulating monocyte trafficking in cancer.
Main Methods:
- Analysis of monocyte infiltration in tumor microenvironments.
- Investigation of monocyte differentiation into proangiogenic macrophages.
- Evaluation of monocyte differentiation into endothelial-like cells for direct neovascularization.
- Preliminary studies in animal models to assess therapeutic strategies.
Main Results:
- Monocytes are actively recruited to the tumor microenvironment.
- Infiltrated monocytes can differentiate into macrophages expressing proangiogenic factors.
- Monocytes can also differentiate into endothelial-like cells, potentially participating directly in neovascularization.
- Animal studies suggest that modulating bone marrow-derived cell trafficking is a viable therapeutic approach.
Conclusions:
- Monocytes play a significant role in regulating tumor neovascularization.
- Monocyte-derived cells contribute to tumor angiogenesis through differentiation into macrophages or endothelial-like cells.
- Targeting the trafficking of bone marrow-derived cells, particularly monocytes, presents a novel and promising strategy for cancer therapy.
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