MAP1LC3B and cancer: To assess the metabolic health within the lung of m/lEV‐treated mice, we performed immunohistochemistry of the lung slides for the localization of MAP1LC3B (LC3), a key autophagy player often upregulated to promote cancer cell survival during metabolic stress (Figure 8f‐j).[36] Remarkably, the expression of the LC3 was upregulated in the lung tissue of mice that developed early metastasis following multiple injections of m/lEVs purified from unmodified 4T1 cells (Figure 8h).