Welcoming Treat: Astrocyte-Derived Exosomes Induce PTEN Suppression to Foster Brain Metastasis.

Metastasis to distant organs depends on pathological crosstalk between tumor cells and various tissue-specific stromal components. Zhang and colleagues recently demonstrated that astrocyte-derived exosomal miR-19a reversibly downregulated PTEN expression in cancer cells, thereby increasing their CCL2 secretion and recruitment of myeloid cell to promote brain metastasis.