MicroRNA-150对NK/T细胞淋巴瘤组织和NK-92细胞辐射敏感性的影响

目的:探讨microRNA-150 (miR-150)对NK/T细胞淋巴瘤组织和NK-92细胞辐射敏感性的影响.方法:选取2010年1月至2016年1月在南方医科大学珠江医院收治的NK/T细胞淋巴瘤患者36例为研究对象,并收集患者的组织标本.所有患者均接受放疗并采用淋巴瘤国际工作组标准((IWG)评价患者的近期疗效,根据疗效分为完全缓解(CR)组和未完全缓解组(Non-CR).实时荧光定量PCR检测患者肿瘤组织及NK/T细胞淋巴瘤细胞系中miR-150的表达量,向淋巴瘤NK-92细胞转染miR-150 mimics,利用MTT法和集落形成实验分析过表达miR-150对NK-92细胞辐射敏感性的影响,流式细胞术检测转染过表达miR-150对NK-92细胞辐射致凋亡的影响,Western blotting实验检测miR-150对凋亡相关蛋白Caspase3和PARP表达的影响.结果:根据IWG标准,12例患者CR,24例患者为Non-CR;与CR组相比,Non-CR组患者miR-150表达量普遍下调(P＜0.05).与正常对照sCD3-CD56+ NK细胞相比,NK/T细胞淋巴瘤组织(9.10±0.19 vs4.01±0.22,P＜0.01)和5种NK/T细胞淋巴瘤细胞系中miR-150呈明显低表达(P＜0.05).过表达miR-150可明显降低辐射后NK-92细胞的增殖能力(P＜0.01)和集落形成能力(P＜0.01),明显提高NK-92细胞的辐射增敏比(10 Gy时辐增敏比为5.375),显著促进辐射诱导的NK-92细胞的凋亡(37.3±1.24)％vs(28.3±2.34)％,P＜0.05],可促进激活的Caspase 3和PARP蛋白表达.结论:miR-150在NK/T细胞淋巴瘤组织标本及体外培养细胞系中的表达呈显著低水平,miR-150表达量低的患者放疗后缓解率低;转染miR-150 mimics能够增强辐射对NK-92细胞增殖的抑制作用和促进辐射诱导致凋亡作用,对NK/T细胞淋巴瘤有辐射增敏作用.

Effect of microRNA-150 on the radiosensitivity of NK/T cell lymphoma tissues and NK-92 cells

Objective:To investigate the expression of MicroRNA-150 (miR-150) in NK/T cell lymphoma tissues and its effect on radio-sensitivity of NK-92 cells.Methods:Thirty-six patients with NK/T cell lynphoma that treated in Zhujiang Hospital Affiliated to Southern Medical University were included as study subjects,and their tissue samples were collected.All the patients received similar radiotherapy,and the short-term efficacy was evaluated by the standard of International Workgroup (IWG) of Lymphoma.The patients were further divided into CR (complete remission) group and Non-CR (non-complete remission) group according the treatment efficacy.The miR-150 expression in lymphoma tissues and NK/T cell lymphoma cell lines were detected by qRT-PCR.The NK-92 cells were then transfected with miR-150 mimics.The effect of miR-150 mimics on NK-92 cell radiosensitivity was analyzed by MTT and colony formation assay;effect of miR-150 mimics on radiation induced apoptosis of NK-92 cells were analyzed by Flow Cytometry;and the effect of miR-150 mimics on the expression of apoptosis-related proteins (Caspase 3 and PARP) in NK-92 cells was determined by Western blotting.Results:According to IWG criteria,12 patients had CR while the other 24 patients had Non-CR.Compared with CR group,the microRNA-150 level in NonCR group was significantly decreased(P＜0.05).Compared with the normal sCD3-CD56+ NK cells,miR-150 was significantly lower in NK/T cell lymphoma tissues (9.10 ±0.19 vs 4.01± 0.22 P＜0.01) and five NK/T cell lymphoma cell lines (P＜0.05);over-expression of miR-150 significantly decreased the proliferation and colony formation of NK-92 cells (all P＜0.01),and increased the sensitivity enhancement ratio (SER) after radiation (the SER was 5.375 after 10 Gy exposure;in addition,over-expressions of miR-150 significantly promoted the radiation-induced apoptosis of NK-92 cells (37.3± 1.24)％ vs (28.3±2.34)％,P＜0.05],and promoted the protein expression of caspase 3 and PARP in NK-92 cells.Conclusion:miR-150 expression significantly decreased in both NK/T cell lymphoms tissues and cell lines.The patients of low miR-150 expression had low CR after radiotherapy.miR-150 mimics transfection promoted radiation-induced apoptosis of NK-92 cells.miR-150 has an enhancement effect on radio-sensitivity of NK/T cell lynphoma.