| First Author | Catena R | Year | 2013 |
| Journal | Cancer Discov | Volume | 3 |
| Issue | 5 | Pages | 578-89 |
| PubMed ID | 23633432 | Mgi Jnum | J:200098 |
| Mgi Id | MGI:5506984 | Doi | 10.1158/2159-8290.CD-12-0476 |
| Citation | Catena R, et al. (2013) Bone marrow-derived Gr1+ cells can generate a metastasis-resistant microenvironment via induced secretion of thrombospondin-1. Cancer Discov 3(5):578-89 |
| abstractText | Metastatic tumors have been shown to establish permissive microenvironments for metastases via recruitment of bone marrow-derived cells. Here, we show that metastasis-incompetent tumors are also capable of generating such microenvironments. However, in these situations, the otherwise prometastatic Gr1(+) myeloid cells create a metastasis-refractory microenvironment via the induction of thrombospondin-1 (Tsp-1) by tumor-secreted prosaposin. Bone marrow-specific genetic deletion of Tsp-1 abolished the inhibition of metastasis, which was restored by bone marrow transplant from Tsp-1(+) donors. We also developed a 5-amino acid peptide from prosaposin as a pharmacologic inducer of Tsp-1 in Gr1(+) bone marrow cells, which dramatically suppressed metastasis. These results provide mechanistic insights into why certain tumors are deficient in metastatic potential and implicate recruited Gr1(+) myeloid cells as the main source of Tsp-1. The results underscore the plasticity of Gr1(+) cells, which, depending on the context, promote or inhibit metastasis, and suggest that the peptide could be a potential therapeutic agent against metastatic cancer. SIGNIFICANCE: The mechanisms of metastasis suppression are poorly understood. Here, we have identified a novel mechanism whereby metastasis-incompetent tumors generate metastasis-suppressive microenvironments in distant organs by inducing Tsp-1 expression in the bone marrow-derived Gr1+myeloid cells. A 5-amino acid peptide with Tsp-1-inducing activity was identified as a therapeutic agent against metastatic cancer. |
