In vitro evidence of Piperlongumine as a potential radiosensitizer in cervical cancer cells

Background Radiotherapy has been applied for the treatment of cervical cancer (CC), and our current study aims to reveal the mechanism of Piperlongumine on strengthening radiotherapy sensitization in CC. Methods The cell counting kit-8 assay was applied to explore the inhibitory effects of Piperlongumine on the viability of CC cells HeLa and SiHa, and the mechanism of action of Piperlongumine on strengthening radiotherapy sensitization in CC cells. The generation of reactive oxygen species in CC cells after the treatment of different concentrations of Piperlongumine, meanwhile, was observed under a fluorescence microscope, while the assay of flow cytometry was adopted to determine the cell cycle. Further, the content of oxidative stress indicators glutathione (GSH) and thioredoxin reductase (TrxR) and the protein level of DNA damage indicator H2AX was quantified using the enzyme-linked immunosorbent assay (ELISA) and western blotting, respectively. Results The intervention of Piperlongumine evidently reduced the proliferation and survival fraction of CC cells following irradiation at different radiation dosages. Meanwhile, the intervention of Piperlongumine led to increased reactive oxygen species production, while inducing DNA damage (as evidenced by increased H2AX levels), disrupting redox homeostasis (reduced GSH, increased TrxR), and promoting G2/M phase arrest in CC cells. Due to the lack of in vivo validation and the incomplete elucidation of certain mechanisms in this study, future work is needed. Conclusion The current study elucidates the mechanisms of Piperlongumine on strengthening radiotherapy sensitization in CC.