肿瘤相关巨噬细胞对胃癌MGC-803细胞恶性生物学行为的影响

Effect of tumor-associated macrophages on malignant biological behaviors of gastric cancer MGC-803 cells

目的:探讨肿瘤相关巨噬细胞(tumor-associated macrophage,TAM)对胃癌MGC-803细胞增殖、迁移、侵袭、凋亡的影响及其可能的作用机制。方法:体外培养人单核细胞株THP-1,加入佛波酯(PMA)和IL-4后,用ELISA法检测细胞培养上清液中IL-12、IL-10的水平。取对数生长期MGC-803细胞和M2型TAM,根据培养方式不同分为单独细胞培养组、非接触共培养组和接触共培养组,用MTT法、Transwell小室法分别检测MGC-803细胞的增殖、迁移和侵袭能力,用AnnexinV-FITC/PI双染流式细胞术检测MGC-803细胞的凋亡和细胞周期变化,用qPCR、Western blotting分别检测MGC-803细胞中MMP-9、MMP-2 mRNA和蛋白的表达水平。结果:与PMA组相比,PMA+IL-4组细胞上清液中IL-12水平显著降低、IL-10水平显著升高(均P<0.05),成功将THP-1细胞诱导分化为M2型TAM。与单独细胞培养组相比,非接触共培养组、接触共培养组(:1)MGC-803细胞的增殖率显著升高(均P<0.05);(2)细胞的迁移、侵袭数量升高(均P<0.05);(3)细胞凋亡率显著降低(均P<0.05);(4)S、G2期细胞的数量升高、G1期数量降低(均P<0.05)(;5)细胞中MMP-9、MMP-2 mRNA和蛋白的表达水平均显著升高(均P<0.05)。结论:TAM可促进胃癌MGC-803细胞增殖、迁移和侵袭,解除细胞G1期阻滞,减少细胞凋亡,其机制可能与上调胃癌细胞MMP-9、MMP-2表达有关。

Objective: To investigate the effects of tumor-associated macrophages(TAM) on proliferation, migration, invation and apoptosis of gastric cancer MGC-803 cells and the possible mechanisms. Methods: Human monocyte THP-1 was cultured in vitro. After being added with PMA and IL-4, the levels of interleukin-12(IL-12) and interleukin-10(IL-10) in cell supernatant were detected by enzyme-linked immunosorbent assay(ELISA). MGC-803 cells at logarithmic phase and M2-type TAM cells were divided into single cell culture group, non-contact co-culture group and contact co-culture group according to different culture methods. MTT assay was used to detect the proliferation of MGC-803 cells, Transwell assay was used to detect cell migration and invasion, and Annexin V-FITC/PI staining flow cytometry was used to examine the apoptosis and cell cycle changes of MGC-803 cells;In addition, the mRNA and protein expressions of matrix metalloproteinase-9(MMP-9) and MMP-2 were detected by Real-time fluorescence quantitative PCR(qPCR) and Western blotting. Results: Compared with PMA group, the level of IL-12 in cell supernatant of PMA+IL-4 group decreased significantly while the level of IL-10 increased significantly(all P<0.05), indicating THP-1 cells were successfully induced to differentiate into M2-type TAM. Compared with the single cell culture group, the non-contact co-culture group and the contact co-culture group exhibited:(1) significantly increased proliferation rate of MGC-803 cells(P<0.05);(2) increased number of migrated and invaded cells(all P < 0.05);(3) significantly decreased apoptotic rate(P<0.05);(4) increased proportion of S, G2 phase cells and decreased proportion of G1 phase cells(all P<0.05);and(5) significantly increased mRNA and protein expressions of MMP-9 and MMP-2(all P<0.05).Conclusion: TAM can promote the proliferation, migration and invasion of gastric cancer MGC-803 cells, relieve G1 phase arrest and reduce cell apoptosis, which may be related to the up-regulation of MMP-9 and MMP-2 expression in gastric cancer cells.