Hypoxia promotes invasion of retinoblastoma cells in vitro by upregulating HIF-1α/MMP9 signaling pathway.

Abstract

The aim of this study is to investigate the effect of hypoxia-inducible transcription factors-1α (HIF-1α)/matrix metalloproteinase 9 (MMP9) signaling pathway on hypoxia triggered invasion in retinoblastoma cell line HXO-RB44. HXO-RB44 cells were cultured under hypoxia conditions for 24 h. The effect of hypoxia on invasion ability of HXO-RB44 cells was monitored with transwell invasion assay; the mRNA and protein expression levels of HIF-1α and MMP9 were detected by Real-time polymerase chain reaction (RT-PCR) and Western blot; luciferase assay was performed to assess the MMP9 regulation by HIF-1α, and HIF-1α regulation by hypoxia. Furthermore, HIF-1α and MMP9 siRNA were used to investigate the effect of HIF-1α/MMP9 signaling on hypoxia-induced cell invasion. The results demonstrated that hypoxia could promote HXO-RB44 cells invasion. The mRNA and protein level of HIF-1α and MMP9 were upregulated by hypoxia treatment, whereas HIF-1α and MMP9 siRNA could reverse these processes. Hypoxia promotes retinoblastoma cell line HXO-RB44 invasion by activating HIF-1α/MMP9 signaling pathway.