AIM: To evaluate the effect of leech extract on human retinoblastoma WERI-RB-1 cells.

METHODS: WERI-RB-1 cells with different concentrations of leech extracts(0.02, 0.04, 0.08 and 0.16U/mL)were cultured in vitro for 0, 24, 48 and 72h. The optimal drug intervention concentration and time were selected by CCK-8 method for subsequent experiments. WERI-RB-1 cells cultured in vitro were divided into control group(normal culture medium)and experimental group(culture medium containing leech extract). Flow cytometry was used to detect the effects of drugs on cell cycle and cell apoptosis, and Transwell invasion assay was used to detect the effects of drugs on cell invasion abilit.

RESUITS: According to the detection results of CCK-8 method, the optimal intervention conditions were 0.04 and 0.08U/mL leech extract for 48h. The cells in the leech extract intervention were mainly blocked at G2/M stage, and the positive cell rates in the 0.04 and 0.08U/mL groups were(12.59±5.36)% and(14.79±4.12)%, respectively, which were significantly higher than those in the control group \〖(3.00±2.32)%, P<0.01\〗. The apoptosis rate of the cells in the 0.04 and 0.08U/mL groups was(37.91±3.44)% and(33.05±2.25)%, respectively, which were significantly higher than that in the control group \〖(4.64±2.56)%, P<0.01\〗. The results of Transwell invasion assay showed that the number of cells under the Transwell chamber in the experimental group was significantly than that in the control group, indicating that the leech extract could inhibit cell invasion.

CONCLUSION: The leech extract can inhibit the proliferation and invasion of human retinoblastoma cells and induce cell apoptosis in vitro.