Effect of AG490 on JAK2/STAT3 signaling pathway in human retinoblastoma HXO-RB44 cell lines / 中南大学学报(医学版)

ABSTRACT

To investigate the role of Janus kinase (JAK) inhibitor AG490 in the anti-proliferation and cell cycle in human retinoblastoma HXO-RB44 cell lines in vitro, and to explore its effect on the expression of JAK2/signal transducer and activator of transcription 3 (STAT3).
 Methods: Cells were divided into an experiment group and a control group, and the experiment group was further divided into 6 sub-groups according to different AG490 concentrations (6.25, 12.50, 25.00, 50.00 or 100.00 μmol/L). Cell proliferation in the different groups was analyzed by cell vitality determination. Cell cycle distribution and apoptosis rate were examined by flow cytometry. The protein levels of STAT3, p-STAT3 and vascular endothelial growth factor (VEGF) were detected by Western blot.
 Results: After 48 h treatment with AG490, the viability of HXO-RB44 cells was reduced in a concentration-dependent manner. Compared with the control group, there was no significant difference in the experiment groups except the 6.25 μmol/L group (all P>0.05). The apoptosis rates in the experiment groups were significantly increased with increase in concentration of AG490 compared with that in the control group (all P0.05), but there were significant differences in the other experiment groups (all P<0.05). 
 Conclusion: JAK inhibitor AG490 can inhibit proliferation and promote apoptosis of the retinoblastoma HXO-RB44 cells through down-regulation of JAK2/STAT3 signaling pathway.