CLTB and cancer: The functional role of sEV‐CLTB in endothelial cell modulation suggests that tumor progression and metastasis are potentiated through sEV‐CLTB‐mediated angiogenesis, which facilitates cancer cell dissemination, induces pulmonary vascular permeability and tumor‐endothelial adhesion, and promotes tumor cell extravasation during metastatic colonization.