不同免疫细胞及PD-1单抗杀伤前列腺癌细胞的初步研究

Preliminary Study on the Killing of Prostate Cancer Cells by Different Immune Cells and PD-1 Monoclonal Antibody

目的:本研究拟通过对比不同效应细胞杀伤前列腺癌细胞的效果,探讨免疫疗法治疗前列腺癌的可行性及策略。方法:通过细胞因子诱导外周血单个核细胞培养细胞因子诱导的杀伤细胞(cytokineinducedkillercells,CIK)细胞及天然杀伤细胞(naturalkillercells,NK)细胞,同时复苏培养前列腺癌细胞系PC3、LNCaP、DU145为靶细胞;效应组分别为CIK细胞、NK细胞、程序性死亡受体(programmedcelldeathprotein1,PD-1)单抗+NK细胞,在不同效靶比的情况下(0.1∶1、0.5∶1、1∶1、5∶1、10∶1、15∶1、20∶1),加入CCK8试剂,孵育3.5h后,用酶标仪测定450nm波长光密度(opticaldensity,OD)值的方法检测杀伤效率。结果:CIK细胞对3种靶细胞的杀伤效率差异明显,在效靶比为10∶1、15∶1、20∶1时逐步增高,且与其他两组效应组相比差异有统计学意义(P<0.05);NK细胞对3种靶细胞的杀伤效率差异极显著,对LNCap细胞系的杀伤效率能达到92.03%±9.95%,而对于PC3细胞系无杀伤效果,甚至随着效靶比的增加促进肿瘤细胞增殖;PD-1单抗与NK细胞联合应用对3种前列腺癌细胞的杀伤效率与单独NK细胞相比,各组间差异均无统计学意义(P>0.05)。结论:CIK细胞过继性回输治疗前列腺癌的效果与患者所患前列腺癌类型相关;NK细胞、PD-1+NK细胞过继免疫治疗对于早期的激素敏感性前列腺癌有一定的治疗作用,但该治疗方法可能具有一定的风险性;PD-1单抗不适用于前列腺癌的治疗,NK细胞过继性回输联合PD-1抑制剂的治疗策略并不适用于前列腺癌治疗,但是此结论还有待动物实验进一步验证。

Objective: To explore the feasibility and strategies of immunotherapy for prostate cancer by comparing the killing effects of different effector cells on prostate cancer cell lines. Methods: CIK and NK cells were cultured by inducing peripheral blood mononuclear cells(PBMCs) with cytokines, and prostate cancer cell lines PC3, LNCaP and DU145 were resuscitated and cultured. The effect group consisted of CIK cells, NK cells, and PD-1 mAb +NK cells. CCK8 reagent was added in different effector to target ratios(0.1∶1, 0.5∶1, 1∶1, 5∶1, 10∶1, 15∶1, 20∶1), and incubated for 3.5 h. Then the killing efficiency was detected by comparing the OD values of 450 nm wavelength with Microplate Reader. Results: The killing efficiency of CIK cells against the three target cells was significantly different, and increased gradually when the effector to target ratio was 10∶1, 15∶1 and 20∶1;and difference in the killing effect was significant between the CIK group and other two groups(P<0.05). The killing efficiency of NK cells against the three target cells was significantly different;the highest killing effect of NK cells on LNCap cell line was 92.03%±9.95%;however, NK cells were ineffective to PC3 cell line, and even promoted the growth of tumor cell line with the increase of the effector to target ratio. The killing efficiency of PD-1 mAb plus NK cells against the three prostate cancer cell lines was not significantly different from that of NK cells alone(P>0.05). Conclusion: The effect of adoptive transfusion of CIK cells in the treatment of prostate cancer depends on the type of prostate cancer. Adoptive immunotherapy with NK cells or PD-1+NK cells has a positive therapeutic effect on early hormone-sensitive prostate cancer, though there is a risk. Neither PD-1 mAb nor NK cells plus PD-1 inhibitors is suitable for the treatment of prostate cancer. This conclusion needs to be further verified by animal experiments.