Activated tumor cell integrin ?v?3 cooperates with platelets to promote extravasation and metastasis from the blood stream.

ABSTRACT: Metastasis is the main cause of death in cancer patients, and understanding mechanisms that control tumor cell dissemination may lead to improved therapy. Tumor cell adhesion receptors contribute to cancer spreading. We noted earlier that tumor cells can expressing the adhesion receptor integrin ?v?3 in distinct states of activation, and found that cells which metastasize from the blood stream express it in a constitutively high affinity form. Here, we analyzed steps of the metastatic cascade in vivo and asked, when and how the affinity state of integrin ?v?3 confers a critical advantage to cancer spreading. Following tumor cells by real time PCR, non-invasive bioluminescence imaging, intravital microscopy and histology allowed us to identify tumor cell extravasation from the blood stream as a rate-limiting step supported by high affinity ?v?3. Successful transendothelial migration depended on cooperation between tumor cells and platelets involving the high affinity tumor cell integrin and release of platelet granules. Thus, this study identifies the high affinity conformer of integrin ?v?3 and its interaction with platelets as critical for early steps during hematogenous metastasis and target for prevention of metastatic disease.

SUBMITTER: Weber MR 

PROVIDER: S-EPMC4888909 | biostudies-literature | 2016 Apr

REPOSITORIES: biostudies-literature