Oxygen and nutrients are necessary for survival of cancer cells, thus angiogenesis is essential for tumor growth and metastasis.147 Zhuang et al. reported that exosomal miR-9 enhances angiogenesis by activating JAK/STAT pathway.148 Moreover, human bronchial epithelial (HBE) cells-derived exosomal miR-21 can promote angiogenesis by activating STAT3 and increasing expression of VEGF.149 Furthermore, circulating exosomal miR-23a levels are positively correlated with lung cancer proangiogenic activities. This evidence concerns the gene STAT3 and lung cancer.