IL-34对人急性单核细胞白血病细胞恶性生物学行为的影响

Effect of IL-34 on malignant biological behavior of human acute monocytic leukemia cells

目的:探讨过表达IL-34对急性单核细胞白血病(acute monocytic leukemia,AMo L)细胞恶性生物学行为的影响。方法:构建IL-34过表达载体,制备慢病毒载体p CDH-GFP,感染AMo L细胞系THP1和MOLM-13,通过细胞增殖实验、集落形成实验、PI染色检测细胞周期法和Annexin-V/PI法检测IL-34对AMo L细胞的增殖、集落形成、细胞周期和凋亡的影响,通过流式细胞术分析过表达IL-34对细胞分化表型的影响,通过裸鼠皮下成瘤模型观察肿瘤大小、质量差异和巨噬细胞募集情况。结果:实验组THP1和MOLM-13细胞IL-34 m RNA表达水平分别比对照组提高近4 000倍和近3 000倍(均P<0.01),表明已成功构建稳定过表达IL-34的AMo L细胞系。体外细胞实验结果显示,过表达IL-34提高THP1和MOLM-13细胞的增殖[72 h:(0.738±0.003)vs(0.646±0.008),(0.290±0.004)vs(0.247±0.004);均P<0.01]和集落形成能力[(127.00±3.37)vs(86.00±4.08)个,(160.70±4.70)vs(116.70±3.93)个;均P<0.01],对细胞的凋亡没有显著影响(均P>0.05);单核-巨噬细胞分化标志物CD11b和CD14表达水平升高,未成熟细胞标志物CD71表达水平减低,表明IL-34促进了AMo L细胞向单核-巨噬细胞方向分化(均P<0.05)。裸鼠体内荷瘤实验可见,过表达IL-34促进瘤组织内巨噬细胞募集(P<0.01)。结论:过表达IL-34提高AMo L细胞的增殖和集落形成能力,促进细胞向单核-巨噬细胞分化,并促进肿瘤内巨噬细胞的募集。

Objective：To study the effects of IL-34 over-expression on malignant biological behavior of acute monocytic leukemia（AMo L） cells. Methods： The lentiviral vector p CDH-GFP for over-expressing IL-34 was constructed and infected into AMo L cell lines（THP1 and MOLM-13）. Then its effects on proliferation, colony forming and cell cycle as well as apoptosis were tested by the MTS,colony formation assay and Annexin-V/PI staining, respectively. The cell differentiation phenotypes were assessed by fflow cytometry.Nude mice xenograft model was established to observe the tumor size and mass as well as the macrophages recruitment. Results： q PCR analysis showed that the expression of IL-34 m RNA in THP1-IL-34 and MOLM-13-IL-34 cells was nearly 4 000 and 3 000 folds higher than their respective control cells（all P〈0.01）, indicating that AMo L cell lines over-expressing IL-34 were successfully established. In vitro study showed that over-expression of IL-34 in AMo L cell lines promoted their proliferation potential（72 h： [0.738 ± 0.003] vs[0.646±0.008]; [0.290±0.004] vs [0.247±0.004]; all P〈0.01） and colony formation（[127.00 ± 3.37] vs [86.00±4.08]; [160.70±4.70] vs[116.70±3.93]; all P〈0.01）, whereas had little effect on apoptosis（all P〉0.05）. Over-expression of IL-34 promoted AMo L cell differentiation towards monocyte-macrophage lineage as the expressions of the monocyte-macrophage markers, CD11 b and CD14, were increased whereas the expression of immature marker, CD71, was decreased in AMo L cell lines over-expressing IL-34（all P〈 0.05）. Nude mice xenograft model showed that IL-34 over-expression stimulated macrophage recruitment in tumor tissues（P〈0.01）. Conclusion：Over-expression of IL-34 in human AMo L cell lines promotes their proliferation, colony forming potential and differentiation towards monocyte-macrophage lineage. Furthermore, IL-34 participates in the process of macrophages recruitment in vivo.