目的:通过体外诱导探索肿瘤相关巨噬细胞(TAM)及肿瘤坏死因子-α(TNF-α)对肿瘤细胞增殖和迁移的影响;在此基础上研究羧胺三唑(CAI)是否可以通过影响TAM及其来源的TNF-α间接抑制肿瘤细胞的增殖和迁移。方法建立腹腔巨噬细胞或RAW264.7细胞与Lewis 肺癌细胞(LLC)的共培养体系,研究巨噬细胞对 LLC 细胞增殖和迁移的影响;观察TNF-α或其中和抗体对LLC增殖或迁移的影响;向共培养体系中加入CAI和(或)地塞米松(DEX),观察药物对巨噬细胞诱导的LLC增殖的影响;用CAI和(或)DEX预先处理RAW264.7细胞,然后检测不同药物处理组RAW264.7细胞诱导LLC细胞迁移和TNF-α表达的差异。结果与腹腔巨噬细胞共培养的 LLC细胞比单独培养的LLC细胞的增殖显著增加,在最为明显的一组中,前者比后者的增殖增加(422.5±77.7)%;与 RAW264.7细胞共培养的 LLC 细胞比单独培养的 LLC 细胞迁移增加(98.8±6.2)%。在这两个过程中,TNF-α均发挥重要作用,0.1 ng/ml TNF-α增加LLC细胞增殖的作用显著,0.1μg/ml TNF-α中和抗体即可显著抑制巨噬细胞对LLC细胞的迁移诱导作用;CAI预处理的RAW264.7细胞促进LLC细胞迁移的能力减弱,其中TNF-α表达相比仅用LLC条件培养基诱导的对照组显著降低(CAI预处理组与对照组TNF-α的相对表达量为0.66±0.03 vs.1.00±0.05,P<0.01)。结论巨噬细胞和TNF-α对LLC细胞的增殖和迁移有显著影响;CAI可以通过下调肿瘤条件诱导的巨噬细胞中的TNF-α水平间接抑制肿瘤细胞的迁移。
Objective To investigate the effects of tumor associated macrophages(TAM) and tumor necrosis factor-α(TNF-α) on tumor cell proliferation and migration in the induction systems established in vitro. To investigate whether carboxyamidotriazole(CAI) can inhibit the tumor cell proliferation and migration indirectly by down-regulating the TNF-αexpression in TAM. Methods The peritoneal macrophages or RAW264.7 macrophages were co-cultured with the Lewis lung carcinoma (LLC) cells, and the effects of the macrophages on LLC proliferation and migration were assayed with CCK-8 and the crystal violet, respectively. TNF-α or its neutralizing antibody was added to stimulate or block LLC proliferation or migration. The effects of CAI and/or dexamethasone(DEX) on LLC proliferation induced by peritoneal macrophages were observed after adding them to the co-culture system. RAW264.7 was pre-treated with CAI and/or DEX, and the ability to induce LLC migration and the TNF-αexpression in RAW264.7 with different treatments were investigated. Results The proliferation and migration of LLC cells in the co-culture systems were significantly enhanced compared with the cells cultured alone. The proliferation and migration of the co-cultured LLC cells could be increased by (422.5±77.7)%and (98.8± 6.2)%, respectively. The proliferation could be significantly stimulated by low level of TNF-α(0.1 ng/ml). LLC migration induced by macrophages could be greatly inhibited by the TNF-α neutralizing antibody. The ability of RAW264.7 to induce LLC migration was impaired and the TNF-αexpression in RAW264.7 was down-regulated after CAI treatment (relative expression of TNF-α in CAI pre-treatment group and control group were 0.66±0.03 vs. 1.00±0.05, P〈0.01). Conclusion Macrophages and TNF-α have significant effects on LLC proliferation and migration in the co-culture systems in vitro. CAI can indirectly inhibit the tumor cell migration by down-regulating the TNF-αexpression in TAMs.