ISG15 and neoplasm: In the Exo-ISG15 group, the expression of CD31, Ki67 and Vimentin was lower than that in the control group, the expression of ESRP1 and E-cadherin was higher than that in the control group, and a large area of necrosis appeared in the tumour centre, indicating that tumour growth was inhibited and not prone to metastasis.