Mechanism Of Anti-tumor Effect Of NK92 Cells Regulated By IL-27 And IL-15

Objective:To study the anti-tumor effects of interleukin 27(IL-27)and interleukin 15(IL-15)in NK92 cells,clarify the signal pathway mechanism of IL-27 and IL-15 in the anti-tumor effect of NK92 cells,provide a new theoretical basis for further understanding the role of NK92 cells in anti-tumor,and provide experimental basis for the application of NK92 cells in tumor immunotherapy.Methods:Non-obese diabetic/severe combined immunodeficiency mice(NOD/SCID)aged 6-8 weeks were used to construct prostate cancer cell DU 145 and PC-3 cell tumor models.The levels of IL-15 secreted by HIL-15NK92 at different concentrations of IL-27 were analyzed by ELISA.The killing effects of NK92 cells and HIL-15NK92 on target cells were detected by lactate dehydrogenase release assay.Flow cytometry was used to analyze the expression of NKG2D,NKp30 and NKp46 on NK92 cells and HIL-15NK92 cells,as well as the secretion of perforin and granzyme B.CCK-8 kit was used to detect the effect of IL-27 on the proliferation of HIL-15NK92 cells.The effect of IL-27 on the migration ability of HIL-15NK92 cells was detected by Transwell migration assay.Western Blot was used to detect the expression of STAT1,P-STAT1,STAT3,P-STAT3,STAT5 and P-STAT5 on NK92 cells and HIL-15NK92 cells.Results:IL-27 and IL-15 can promote the expression of NKG2D,NKp30 and NKp46 on NK92 cells and HIL-15NK92 cells(P<0.05).IL-27 and IL-15 could improve the secretion of Perforin by NK92 cells(P<0.05),but did not affect the secretion of Granzyme B.The appropriate concentration of IL-27 can significantly promote the killing ability of NK92 cells and HIL-15NK92 cells to target cells(P<0.01),and the 30 ng/mL IL-27 has the strongest promoting effect on the cytotoxicity of NK92 cells(P<0.01).IL-27 can up-regulate the phosphorylation of STAT1,STAT3 and STAT5 in NK92 cells and HIL-15NK92 cells(P<0.01).IL-27 promotes the secretion of IL-15 by HIL-15NK92 cells(P<0.01),promotes their migration(P<0.05)and inhibits their proliferation(P<0.05).Local combination therapy of IL-27 and NK92 cells,IL-27 and HIL-15NK92 cells could significantly prolong the survival time of mice bearing prostate cancer(P<0.05).Conclusion:IL-27 and IL-15 enhance NK92 cell killing to solid tumor cells and blood tumor cells by promoting the expression of NKG2D,NKp30 and NKp46 receptors on NK92 cell surface and the secretion of perforin,which is related to the up-regulation of STAT1,STAT3 and STAT5 phosphorylation levels in JAK-STAT pathway.Local combination therapy with IL-27 and NK92 cells,IL-27 and HIL-15NK92 cells could significantly prolong the survival time of mice bearing prostate cancer.