Notoginsenoside R1 induces oxidative stress and modulates LPS induced immune microenvironment of nasopharyngeal carcinoma

Background: Nasopharyngeal carcinoma (NPC) is a malignant tumor with high incidence. Notoginsenoside R1 (NGR1) is the main active compound of total Panax notoginseng saponin, and has multiple anti-tumor effects. This study aimed to investigate the effect and mechanism of NGR1 in NPC.

Materials: NPC cells were treated with different doses of NGR1. The NGR1 function in NPC was evaluated using Cell Counting Kit-8, Transwell, Western blot, flow cytometry, immunofluorescence assay, and quantitative real-time PCR. Meanwhile, the NGR1 mechanism in NPC was assessed by rescue experiments. Furthermore, the NGR1 function in vivo was determined by constructing an NPC xenotransplantation model, TUNEL, and immunohistochemistry assays.

Results: NGR1 repressed NPC cell growth and invasion but facilitated NPC cell apoptosis and oxidative stress. Also, NGR1 alleviated inflammation in NPC cells. Mechanistically, NGR1 restrained NPC cell growth and induced oxidative stress in NPC cells, while these effects were abolished after lipopolysaccharide (an activator of the TRAF6/NF-κB pathway) treatment, implying that NGR1 reduced NPC cell growth and induced oxidative stress in NPC cells by the inactivation of TRAF6/NF-κB axis. Moreover, in vivo studies further proved the palliative effect of NGR1 on NPC.

Conclusion: NGR1 inhibited NPC cell growth and induced oxidative stress in NPC cells by inactivating TRAF6/NF-κB axis.