It is well established that interactions between cancer cells with and non-cancerous cells in the tumor microenvironment and/or with soluble factors released from these cells, drive tumor progression towards metastasis.
Drivers of metastasis are cells or molecules whose activity is required for the targeted migration of tumor cells to the secondary target organ and for their survival and propagation within this organ.
Metastasis drivers may be grouped into 2 major groups: Drivers that are intrinsic to tumor cells and drivers that originate in the microenvironment of the secondary target organ. Both types of drivers are candidates to serve as targets for therapy.
Here we report on the identification and function of CCR4, a tumor-associated driver of melanoma brain metastasis.
A key initial event in brain metastasis is the rapid activation of microglial cells. Molecular signals that activate microglia cells induce the release of cytokines which take part in shaping the malignancy phenotype of brain metastasizing tumor cells. Microglial cells function thus as microenvironmental drivers of melanoma brain metastasis.
This study was supported by The Dr. Miriam and Sheldon G. Adelson Medical Research Foundation (Needham, MA).