目的探讨肿瘤相关巨噬细胞(TAMs)中RIP140的表达对肝癌细胞侵袭、增殖的影响。方法慢病毒介导小鼠腹腔巨噬细胞(PMs)RIP140的过表达,Western blot和Real-time PCR(q RT-PCR)分别检测PMs中RIP140蛋白以及核酸表达水平,流式细胞仪分析慢病毒转染率;Western blot、细胞免疫荧光和q RT-PCR检测肝癌条件培养基(HCM)刺激PMs后TAMs中RIP140的表达变化;HCM刺激PMs以及HCM刺激过表达RIP140的PMs,q RT-PCR检测TAMs极化指标以及NF-κB和IL-6的表达;Transwell实验和细胞流式凋亡实验检测肝癌细胞的侵袭和凋亡;肝癌细胞和PMs以4∶1比例注射于BALB/c裸鼠皮下,建立裸鼠皮下肝癌模型,成瘤癌组织HE染色和免疫组化评定肝癌组织大体生长情况和肝癌细胞增殖能力。结果慢病毒介导PMs RIP140的过表达,病毒转染效率高,RIP140过表达明显;HCM刺激PMs后,TAMs中RIP140呈低表达;HCM诱导TAMs呈M2型极化,并且与肿瘤生长密切相关的NF-κB-IL-6轴处于活化状态;TAMs可促进肝癌细胞侵袭和增殖,抑制肝癌细胞凋亡。TAMs过表达RIP140可抑制HCM介导的TAMs M2型极化并抑制NF-κB/IL-6通路的激活,减少IL-6的释放;除此之外,TAMs过表达RIP140可抑制肝癌细胞的侵袭和增殖,促进肝癌细胞的凋亡。结论过表达RIP140的TAMs可抑制肝癌细胞的侵袭和增殖。其机制可能与TAMs过表达RIP140后抑制TAMs M2型极化有关。
Objective To investigate the role of receptor-interacting protein 140(RIP140) in tumor-associated macrophages(TAMs) in the invasion and proliferation of hepatoma cells in vitro. Methods Western blotting, q RT-PCR and flow cytometry were performed to examine the effects of lentivirus-mediated RIP140 over-expression in mouse peritoneal macrophages(PMs).Western blotting, q RT-PCR and immunofluorescence staining were used to detect the expression of RIP140 in TAMs following stimulation of the PMs with hepatocellular carcinoma conditioned medium(HCM) for 24 h. The polarization index and the expression of NF-κB and IL-6 were detected using q RT-PCR in TAMs in HCM-stimulated PMs with or without RIP140 overexpression. Transwell assay and flow cytometry were used to estimate the cell invasion and apoptosis. HE staining and immunohistochemical staining were used to analyze the effects of RIP140-over-expressing macrophages on the growth and tumor formation of H22 cells in BALB/c nude mice. Results The lentivirus vector efficiently mediated RIP140 over-expression in mouse PMs. HCM stimulation significantly inhibited RIP140 expression in the TAMs and promoted their M2-like polarization. Over-expression of RIP140 in PMs suppressed the invasion and induced apoptosis of HCC cells. RIP140 overexpression inhibited HCM-induced M2 polarization and the activation of NF-κB/IL-6 axis in the TAMs, and RIP140-overexpressing TAMs obviously suppressed the growth of H22 cell xenograft in nude mice. Conclusion Over-expression of RIP140 in TAMs suppresses the growth and proliferation of hepatoma cells possibly by inhibiting M2 polarization of the TAMs.