Abstract: Objective To investigate the effect and mechanism of IGF-1R on the growth and apoptosis of retinoblastoma cells. Methods Retinoblastoma cell line WERI-Rb-1 transfected with siRNA control and IGF-1R siRNA, the levels of IGF-1R in transfected cells were detected by RT-qPCR and Western blot, cell proliferation was detected by MTT, detection of cell clone formation by plate cloning assay, cell apoptosis was detected by flow cytometry, Western blot was used to detect the levels of cleaved caspase-3, Bax, p38MAPK and p-p38MAPK in the cells. Results After transfection of IGF-1R siRNA, the levels of IGF-1R mRNA and protein were decreased（P<0.05）. The proliferation and colony forming ability of transfected IGF-1R siRNA decreased（P<0.05）, the apoptosis rate and the levels of cleaved caspase-3, Bax and p-p38MAPK in the cells were increased（P<0.05）. Conclusions Downregulation of IGF-1R inhibits the growth of retinoblastoma cells, promoting apoptosis of retinoblastoma cells, the mechanism of action is related to cleaved caspase-3, Bax and p-p38MAPK.

Key words: Retinoblastoma, Apoptosis, IGF-1R, Growth