Photodynamic therapy-mediated modulation of inflammatory cytokine production by Epstein–Barr virus-infected nasopharyngeal carcinoma cells

摘要

Nasopharyngeal carcinoma(NPC)is a malignant disease associated with Epstein–Barr virus(EBV)infection.This study aims to examine the effects of EBV infection on the production of proinflammatory cytokines in NPC cells after the Zn-BC-AM photodynamic therapy(PDT)treatment.Cells were treated with the photosensitiser Zn-BC-AM for 24 h before light irradiation.Quantitative ELISA was used to evaluate the production of cytokines.Under the same experimental condition,HK-1-EBV cells produced a higher basal level of IL-1a(1561 pg/ml),IL-1b(16.6 pg/ml)and IL-8(422.9 pg/ml)than the HK-1 cells.At the light dose of 0.25–0.5 J/cm2,Zn-BC-AM PDT-treated HK-1-EBV cells were found to produce a higher level of IL-1a and IL-1b than the HK-1 cells.The production of IL-1b appeared to be mediated via the IL-1b-converting enzyme(ICE)-independent pathway.In contrast,the production of angiogenic IL-8 was downregulated in both HK-1 and HK-1-EBV cells after Zn-BC-AM PDT.Our results suggest that Zn-BC-AM PDT might indirectly reduce tumour growth through the modulation of cytokine production.