title: The initial hours of metastasis: the importance of cooperative host-tumor cell interactions during hematogenous dissemination.
abstract: Tumor cells transit from the primary tumor via the blood circulation to form metastases in distant organs. During this process, tumor cells encounter a number of environmental challenges and stimuli that profoundly impact their metastatic potential. Here, we review the cooperative and dynamic host-tumor cell interactions that support and promote the hematogenous dissemination of cancer cells to sites of distant metastasis. In particular, we discuss what is known about the cross-talk occurring among tumor cells, platelets, leukocytes, and endothelial cells and how these cell-cell interactions are organized both temporally and spatially at sites of extravasation and in the early metastatic niche.
  
  
  CONCLUSIONS
  Metastasis is a function not only of tumor cells but also involves cooperative interactions of those cells with normal cells of the body, in particular platelets and leukocytes. These other cell types alter the behavior of the tumor cells themselves and of endothelial cells lining the vasculature and assist in tumor cell arrest and extravasation at sites of metastasis and subsequently in the establishment of tumor cells in the early metastatic niche. A better understanding of the important role that these contact and paracrine interactions play during metastasis will offer new opportunities for therapeutic intervention.
authors.affiliation: Howard Hughes Medical Institute, Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Myriam
authors.initials: M
authors.lastname: Labelle
authors.forename: Richard O
authors.initials: RO
authors.lastname: Hynes
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000502:physiology*; D002450:Cell Communication / Q000502:physiology*; D006801:Humans; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D009369:Neoplasms / Q000097:blood* / Q000473:pathology*; D009360:Neoplastic Cells, Circulating / Q000473:pathology*