The different expression levels of miR-30a and CD73 were firstly screened in 8 strain cell lines of CRC (SW480, HCT116, LoVo, CaCo2, HT29, RKO, DLD1 and HCT8) by qRT-PCR and western blot analysis (Additional file 1: Figure S1). Here, NT5E is linked to colorectal carcinoma.