TSP1 restored the function of miR-18a-5p in HUVECs. (A, B) Expression of TSP1 in HUVECs transfected with siRNA NC, siTSP1, NC vector and TSP1 vector was examined by qRT-PCR (A) and Western blot (B). (C) The viability of HUVECs after transfection with TSP1 vector or siTSP1 was determined using CCK-8 assay. (D, E) A wound healing assay was performed with HUVECs transfected with TSP1 vector or siTSP1. (F, G) Tube formation (F) and transwell assays (G) were conducted in HUVECs with TSP1 vector or siTSP1. (H-K) Growth, invasion, migration and angiogenesis of HUVECs transfected with NC, miR-18a-5p OE, miR-18a-5p KD, miR-18a-5p OE + TSP1 OE vector or miR-18a-5p KD + siTSP1 were evaluated by CCK-8 (H), wound healing (I), tube formation (J) and transwell assays (K). Data were obtained from three independent repeated experiments. **P<0.05; n.s.: not significant.