抑癌基因Foxo1和PTEN在小鼠NK细胞淋巴瘤发生中的作用探索

Exploration of the Role of Tumor Suppressor Genes Foxo1 and PTEN in the Tumorigenesis of Mouse Natural Killer-Cell Lymphoma

目的:探索抑癌基因Foxo1和PTEN在小鼠NK细胞淋巴瘤发生过程中是否发挥关键作用。方法:利用NKp46-iCre小鼠分别与Foxo1fl/fl、PTENfl/fl小鼠交配,得到NKp46-iCre;Foxo1fl/flPTENfl/fl(Foxo1△NKPTEN△NK)小鼠,即NK细胞内特异性敲除Foxo1和PTEN的小鼠,连续观察小鼠的生长发育和成瘤情况;利用流式细胞术检测NK细胞内Foxo1和PTEN双基因缺失后小鼠主要淋巴器官内的NK细胞的比例变化;利用B16F10恶性黑色素瘤移植瘤小鼠模型观察小鼠NK细胞内Foxo1和PTEN双基因缺失后对NK细胞的肿瘤免疫监视功能的影响。结果:成功建立了NK细胞特异性Foxo1和PTEN双基因缺失小鼠模型,连续观察小鼠46周,与对照组小鼠(Foxo1fl/fl PTENfl/fl)相比,小鼠生长未见明显异常,未形成自发性肿瘤。与对照组小鼠相比,Foxo1△NKPTEN△NK小鼠的外周血、淋巴结、骨髓、脾脏中NK细胞的比例无明显变化(PB:4.76%±0.46%vs 4.17%±0.64%)(P>0.05,n=8);(BM:1.13%±0.23%vs 1.31%±0.10%)(P>0.05,n=8);(LN:0.50%±0.10%vs 0.85%±0.20%)(P>0.05,n=8);(SP:4.41%±0.65%vs 3.5%±0.24%)(P>0.05,n=8)。B16F10恶性黑色素瘤移植瘤小鼠模型建立后,与对照组小鼠(Foxo1fl/fl PTENfl/fl)相比,Foxo1△NKPTEN△NK小鼠的生存时间比较无统计学差异(P>0.05,n=13)。结论:抑癌基因Foxo1、PTEN在小鼠NK细胞淋巴瘤发生过程中可能不具有关键作用,缺失后对体内NK细胞的肿瘤免疫监视功能影响不大。

Objective:To explore whether tumor suppressor gene Foxo1 and PTEN play a critical role in the tumorigenesis of mouse natural killer-cell lymphoma.Methods:NKp46-iCre mice were crossed with mice carrying floxed Foxo1 alleles(Foxo1^fl/fl)as well as floxed PTEN alleles(PTEN^fl/fl)to generate mice in which Foxo1 and PTEN in NK cells were knock-out,referred as Foxo1^△NK PTEN^△NK.The growth and development of the mice and tumor formation were observed.The flow cytometry was used to detect the percentages of NK cells in main lymphatic organs.B16F10 metanoma model of tumor metastasis was utilized to investigate NK cell-mediated tumor surveillance in vivo after NK cells special deletion of Foxol and PTEN.Results:The mouse model with NK cell-special Foxo1 and PTEN double knockout was established.Compared with control group(Foxo1^fl/flPTEN^fl/fl mice),Foxo1^△NK PTEN^△NK mice were born alive and appeared to be healthy over a period of 46 weeks.No spontaneous tumor formation was observed at this stage.There were no significant differences in NK cell percentages of gated lymphocytes from various organs including blood,bone marrow,peripheral lymph node and spleen between Foxo1^△NK PTEN^△NK mice and Foxo1^fl/fl PTEN^fl/fl mice[PB:4.76%±0.46% vs 4.17%±0.64%(P>0.05,n=8);BM:1.13%±0.23% vs 1.31%±0.10%(P>0.05,n=8);LN:0.50%±0.10% vs 0.85%±0.20%(P>0.05,n=8);SP:4.41%±0.65% vs 3.50%±0.24%(P>0.05,n=8)].B16 F10 melanoma metastasis model of tumor was established,No differences in median survival time were observed in the 2 types of mice(P>0.05,n=13).Conclusion:The simultaneous deletion of the Foxo1 and PTEN genes may not plays significant role in the tumorigenesis of mouse natural killer-cell lymphoma and NK cell-mediated tumor surveillance in vivo.