Abstract: Objective To investigate the expression of survivin and CD+8 cytotoxic T lymphocytes(CTL) of 5-Aminolevulinic acid(5-ALA) mediated photodynamic therapy(PDT) on mouse nasopharyngeal carcinoma(NPC).Methods Mouse NPC model was established by subcutaneous inoculation with CNE 2 cells into the right dorsal area of BALB/c mouse.32 mice were divided into two groups at random,namely PDT group and control group.The expression of survivin and number of CTL infiltrated in tumor tissues were detected by immunohistochemical staining.Results Expression level of survivin in PDT group was significantly lower than that in control group(P<0.05).Compared to control group,the number of CTL in tumors tissue showed no significant change 24h after treatment(P>0.05).The number of CD+8CTLs in tumor tissues of PDT group was significantly higher than that in control group 72h after treatment(P<0.05).Conclusion Suppressing the expression of survivin and immune efficacy might be one of the mechanisms for treating mouse NPC with 5-ALA mediated PDT.

Key words: Photodynamic therapy, 5-Aminolevulinic acid, Nasopharyngeal carcinoma, CD+8CTLs, survivin