Experimental study on immunomodulation and antitumor effects of melatonin in H22 hepatoma-bearing mice

Recently,itwasdemonstratedthatmelatonin(MLT)whichisreleasedmainlyfromthepinealgland,notonlyplayedanimportantroleintheregulationoftheneuroendocrineandlmmunesys-tems,butalsoaffectedtumorgrowthinvivo[l'2].Withthedevelopmentofneuroimmuno-modula-tion,peoplehavebeenstudyingtherolesofMLT-,.lnlmmunomodulationconcerningtheetiology,di-agnosisandtreatmentofinfection,tumorandau-to-immunediseases.InChina,therehavebeenfewreportsinthisfield.Inthisstudy,weobservedtheimmunomodulationandantitumoreffectofMLT…

Experimental study on immunomodulation and antitumor effects of melatonin in H22 hepatoma-bearing mice

To observe immunomodulation and antitumor effect of melatonin (MLT) in tumor-bearing mice. Methods: By means of flow cytometry and MTT colorimetry, the immunological indexes of H22 hepatomabearing mice were investigated. Results: MLT administration could increase the CD4 /CD8 cell ratio in the peripheral blood of the tumor-bearing mice, cooperate with IL-2 to promote the proliferation of lymphocytes and eosinophils, increase NK and LAK activity of splenocytes, and enhance the production of IL-2 from splenocytes.We also found that MLT could inhibit tumor growth and prolong the survival time of the tumor-bearing mice in vivo. Moreover, a synergetic effect of IL-2 and MLT was observed. It seems that MLT hadno effect on H22 hepatoma cell growth in vitro. Conclusion: It is suggested that MLT may be a potential candidate for tumor immunotherapy as one of the biological reaction modulators (BRM).