Conclusion
miR-145 inhibited proliferation and induced apoptosis in Y79 cells. Lower expression of IGF-1R suppressed the proliferation of Y79 cells. miR-145 restrained the proliferation of human retinoblastoma Y79 cells by down-regulating the expression of IGF-1R.
Purpose
To investigate the effect of miR-145 on the proliferation and apoptosis of human retinoblastoma Y79 cells and to explore the underlying mechanism. Method: The Y79 cells were transfected by miR-145 mimics and IGF-1R siRNA with lipofection, respectively. The expression of miR-145 or IGF-1R was detected after transfection by real time-PCR. Cell proliferation inhibition was measured by Cell Counting Kit-8 (CCK-8) assay. Flow cytometry was used to examine cell cycles. Apoptosis was detected by Annexin/PI double immunofluorescence and flow cytometer. The interaction between miR-145 and IGF-1R was tested by luciferase activity measurement.
Results
The expression of miR-145 in the miR-145 mimics group was significantly increased (P<0.05). The proliferation inhibition rate was higher in the miR-145 mimics group (P<0.01). The results of immunofluorescence and flow cytometry showed that ratios of Annexin or Annexin/PI double positive were increased in the miR-145 mimics group (P<0.05). The OD value of proliferation inhibition was lower in the IGF-1R siRNA group (P<0.05). The ratios of Annexin or Annexin/PI double positive were higher in the IGF-1R siRNA group (P<0.05). Luciferase activity was reduced in miR-145 mimics group (P<0.01).