Figure 3. DDX21 rescued the CRC cells proliferation inhibition caused by ZFAS1 knockdown. (A and B) The expression of DDX21 after silencing or overexpression DDX21 in SW620 and SW480 cells by qPCR (A) and western blot (B). (C and D) Rescue experiments detecting the DDX21 mRNA and protein expression levels treated by co-transfection of lncRNA ZFAS1 silencing and DDX21 overexpression vectors or ZFAS1 overexpression with DDX21 silencing vectors in SW620 and SW480 cells assayed by qPCR assay (C) and western blot assay (D). (E–H) The cell proliferation, colony formation, invasion ability, and cellular apoptotic rates were recovered after co-transfected with shRNA ZFAS1 and pcDH-DDX21 vector in SW620 and SW480 cells assayed by cell number monitoring assay (E), cell colony formation assay (F), flow cytometry method (G), trans-well (H) respectively. (I and J) Stratified Kaplan-Meier plot illustrating the impact of ZFAS1 high/low expression on the DFS and OS upon those patients with DDX21 high expression (I), DDX21 high/low expression on the prognosis based on the patients with lncRNA ZFAS1 high expression (J). Data were shown as mean ± s.d.. n = 3 independent experiments. Two-tailed Student’s t-tests were used. *P <0.05; **P <0.01; ***P <0.001; ****P <0.0001.