Is CEACAM1 a lymphangiogenic switch?

Newly formed lymphatic capillaries closely associated with malignant tumors have a key role in metastasis, but much remains to be learned about the trigger and mechanisms of lymphangiogenesis. In this issue of Blood, Kilic and colleagues report that CEACAM1, recognized as a possible lymphangiogenic switch, is expressed in newly formed tumor-associated lymphatic capillaries, and that it can trigger reprogramming of microvascular endothelial cells to lymphatic endothelial cells.