Format

Send to

Choose Destination
Oncogene. 2014 Aug 14;33(33):4203-12. doi: 10.1038/onc.2013.377. Epub 2013 Sep 23.

Macrophage contact induces RhoA GTPase signaling to trigger tumor cell intravasation.

Author information

1
1] Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, Bronx, NY, USA [2] Gruss-Lipper Biophotonics Center, Bronx, NY, USA.
2
The Ben May Department for Cancer Research, University of Chicago, Chicago, IL, USA.

Abstract

Most cancer patients die as a result of metastasis, thus it is important to understand the molecular mechanisms of dissemination, including intra- and extravasation. Although the mechanisms of extravasation have been vastly studied in vitro and in vivo, the process of intravasation is still unclear. Furthermore, how cells in the tumor microenvironment facilitate tumor cell intravasation is still unknown. Using high-resolution imaging, we found that macrophages enhance tumor cell intravasation upon physical contact. Macrophage and tumor cell contact induce RhoA activity in tumor cells, triggering the formation of actin-rich degradative protrusions called invadopodia, enabling tumor cells to degrade and break through matrix barriers during tumor cell transendothelial migration. Interestingly, we show that macrophage-induced invadopodium formation and tumor cell intravasation also occur in patient-derived tumor cells and in vivo models, revealing a conserved mechanism of tumor cell intravasation. Our results illustrate a novel heterotypic cell contact-mediated signaling role for RhoA, as well as yield mechanistic insight into the ability of cells within the tumor microenvironment to facilitate steps of the metastatic cascade.

PMID:
24056963
PMCID:
PMC3962803
DOI:
10.1038/onc.2013.377
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center