[Lani]

Tumors Prepare Lungs for Metastasis Via Induction of Chemoattractants

NEW YORK (Reuters Health) Nov 27 - Primary tumors ready the lungs for metastasis by inducing the expression of inflammatory chemoattractants, according to a report in the November 26th online issue of Nature Cell Biology.

Previous reports have suggested that primary tumors create an environment in the lungs that facilitates the spread of disease to this organ. However, the mechanisms involved were unclear, senior author Dr. Yoshiro Maru, from the University of Tokyo, and colleagues note.

Using murine cancer models, the authors found that distant primary tumors induce the expression of S100A8 and S100A9 in lung tissue. These chemicals attract inflammatory cells as well as tumor cells to the lung.

Treatment with antibodies against these chemoattractants prevented the migration of both types of cells to the lung, the investigators found.

The authors are hopeful that the current insights could lead to novel treatments for preventing metastatic disease.

"Drugs targeting metastatic tumors themselves show only a limited effect in the prevention of metastasis. We propose that suppression of the host response triggered by the primary tumor at early clinical stages or, hopefully, in the premetastatic phase, can prevent the spread of tumors," Dr. Maru's team concludes.

Nat Cell Biol 2006