The study of Zheng et al. confirmed that miRNA-23a in extracellular vesicles is significantly up-regulated and mediates the down-regulation of PTEN when malignant tumour cells are exposed to X-ray irradiation, and that the down-regulation of PTEN plays an important role in the enhancement of pro-angiogenesis [162]. The gene discussed is PTEN; the disease is neoplasm.