低剂量辐射对Lewis肺癌小鼠肿瘤微环境的影响

目的 探讨低剂量辐射(LDR)对Lewis肺癌小鼠肿瘤微环境(TME)的影响,以及高剂量辐射(HDR)前LDR预处理在TME中发挥的效应机制.方法 接种Lewis肺癌细胞(1×106)于雄性C57BL/6小鼠左侧腋下,待小鼠肿瘤直径1 cm左右(12 d),随机分为假手术Sham(1)组、LDR(2)组、HDR(3)组...

Effects of low-dose radiation on tumor microenvironment in mice bearing Lewis lung carcinoma tumors

Objective To investigate the effect of low-dose radiation(LDR)on tumor microenvironment(TME)in murine Lewis lung carcinoma model and the mechanism initiated by LDR pretreatment before high-dose radiation(HDR)in TME.Methods Lewis lung carninoma(LLC)cells(1×10⁶)were inoculated into the left flank of the male mice,until the tumors about 1 cm in diameter(12 d),the mice were randomly divided into Sham(1)operation group,low-dose radiation group(LDR)(2),high-dose radiation group(HDR)(3)and low-dose radiation pretreatment group before high-dose radiation group(LDR-HDR)(4)10 patients/group.Five mice in each group were sacrificed at the same time point on day 14 and 17 after inoculation of Lewis lung cancer cells,stripping the tumor tissues and spleens and detecting the proportion of myeloid-derived suppressor cells MDSC.Testing the tumor infiltrating lymphocyte(TIL),the contents of transforming growth factor-β(TGF-β)and stromal cell-derived factor-1(SDF-1)of Tumor tissues;Blood was collected from ophthalmic vein.Normal distribution test was performed by Shapiro-Wilk,and LSD-t test was used for pair comparison between groups.Results The mean comparison between groups was statistically significant(F=29.666,P<0.001),and the comparison between groups was P_1-2=0.003,P_1-3<0.001,P_3-4=0.030.The data test results of the four groups on day17 were consistent with normal distribution,and the mean difference between groups was statistically significant(F=19.203,P<0.001),and the comparison between groups was P_1-2=0.029,P_1-3<0.001,P_3-4=0.035.the mean comparison between groups was statistically significant(F=13.800,P<0.001),and the comparison between groups was P_1-2=0.011,P_1-3=0.003,P_3-4=0.031.The data test results of the four groups on day 17 were consistent with normal distribution,and the mean difference between groups was statistically significant(F=17.508,P<0.001),and the comparison between groups was P_1-2=0.002,P_1-3=0.004,P_3-4=0.033.The mean comparison between groups was statistically significant(F=29.099,P<0.001),and the comparison between groups was P_1-2=0.005,P_1-3<0.001,P_3-4=0.804.The data test results of the four groups on day 17 were consistent with normal distribution,and the mean difference between groups was statistically significant(F=22.147,P<0.001),and the comparison between groups was P_1-2=0.004,P_1-3=0.001,P_3-4=0.231.The mean comparison between groups was statistically significant(F=30.243,P<0.001),and the comparison between groups was P_1-2<0.001,P_1-3<0.001,P_3-4<0.001.The data test results of the four groups on day 17 were consistent with normal distribution,and the mean difference between groups was statistically significant(F=39.030,P<0.001),and the comparison between groups was P_1-2<0.001,P_1-3=0.022,P_3-4=0.023.The mean comparison between groups was statistically significant(F=13.773,P<0.001),and the comparison between groups was P_1-2=0.008,P_1-3=0.007,P_3-4<0.001.The data test results of the four groups on day 17 were consistent with normal distribution,and the mean difference between groups was statistically significant(F=5.595,P=0.008),and the comparison between groups was P_1-2=0.012,P_1-3=0.369,P_3-4=0.024.Conclusions LDR increases the anti-tumor immune effect of TME in Lewis lung cancer mice.The immune adaptation of LDR can reverse the immunosuppression in TME.