Fig. 2

Macrophages are key components of lung metastases. Cytokines, chemokines, and exosomes driving TAM features and prometastatic functions in the primary tumor, premetastatic niche, and metastatic niche are depicted. TAM heterogeneity in terms of origin, transcriptional signatures, localization, and function is illustrated with different colors. TAMs contribute to lymphangiogenesis and invasion of lymphatic vessels and promote tumor cell dissemination through the lymphatic system and hematogenous route. Pdpn podoplanin, Fn1 fibronectin 1. Created with Biorender.com