LPS诱导巨噬细胞M1型极化对肿瘤生长的影响

Effect of LPS-induced M1 polarization of macrophages on tumor growth

目的 研究脂多糖(lipopolysaccharide,LPS)诱导巨噬细胞M1型极化对肿瘤生长的影响。方法 将Balb/c雌性小鼠随机分为对照组和实验组。Renca细胞皮下建模,待肿瘤体积生长至50mm3时瘤旁注射生理盐水(100μl/只,1次/2d)或LPS(100μg/只,1次/2d),采用流式细胞术检测肿瘤相关巨噬细胞M1型极化水平。将小鼠肿瘤细胞系(ML-1、MC38、Renca)分成三组:空白组(完全培养基加入50%DMEM基础培养基)、对照组(完全培养基加入50%巨噬细胞培养基上清液)和实验组(完全培养基加入50%LPS预处理的巨噬细胞培养基上清液)。采用细胞计数试剂-8(cellcountingkit-8,CCK-8)实验检测肿瘤细胞增殖情况;采用流式细胞术检测肿瘤细胞周期及凋亡情况。结果 经LPS处理后肿瘤相关巨噬细胞M1型比例增多(P<0.001),从而增强其抗肿瘤功能;LPS诱导巨噬细胞M1型极化可显著抑制肿瘤细胞的增殖(Renca:P=0.023;ML-1:P=0.045);LPS诱导巨噬细胞M1型极化可引起肿瘤细胞周期G0/G1(MC38:P=0.011;ML-1:P=0.022)或S期(Renca:P=0.022)阻滞,进而抑制细胞分裂;LPS诱导巨噬细胞M1型极化可引起肿瘤细胞凋亡(Renca:P=0.04;ML-1:P=0.007)。结论 LPS可通过诱导巨噬细胞M1型极化发挥抗肿瘤功能。

Objective To study the effect of lipopolysaccharide(LPS)-induced M1 polarization of macrophages on tumor growth.Methods Female Balb/c mice were randomly divided into control group and experimental group.Renca cells were used to establish subcutaneous tumor model.NaCl(100μl/mice,once every two days)or LPS(100μg/mice,once every two days)was injected to the tumor side when the tumor grew to 50mm3.The M1 polarization level of tumor-associated macrophages was detected by flow cytometry.Mouse tumor cell lines(ML-1,MC38,Renca)were divided into three groups:blank group(complete medium with 50%DMEM basal medium),control group(complete medium with 50%medium supernatant of cultured macrophages)and experimental group(complete medium with 50%medium supernatant of LPS pretreated cultured macrophages).The proliferation of tumor cells was detected by cell counting kit-8(CCK-8).The cell cycle and apoptosis of tumor cells were detected by flow cytometry.Results The proportion of tumor-associated macrophages M1 increased after LPS treatment(P<0.001),thus enhancing its anti-tumor function.LPS-induced M1 polarization of macrophages can significantly inhibit the proliferation of tumor cells(Renca:P=0.023,ML-1:P=0.045).LPS-induced M1 polarization of macrophages blocked G0/G1 phase(MC38:P=0.011,ML-1:P=0.022)or S phase(Renca:P=0.022)of tumor cell cycle,and then cell division was inhibited.LPS-induced M1 polarization of macrophages significantly induced apoptosis of tumor cells(Renca:P=0.04,ML-1:P=0.007).Conclusion LPS can play an anti-tumor role by inducing M1 polarization of macrophages.