聚集诱导发光纳米探针在前列腺癌光热诊疗中的应用

Application of nanoprobe based on aggregation-induced luminescence in photothermal diagnosis and treatment of prostate cancer

背景:基于“分子内运动受限”这一机制构筑的新型聚集诱导发光荧光探针可用于疾病标志物的检测、肿瘤诊断、细菌成像识别等多个方面。目的:构建基于聚集诱导发光的近红外二区纳米探针FA-DSPE-PEG-AIE@NPs,探讨其用于前列腺癌靶向近红外二区荧光成像及光热治疗的潜能。方法:以卵磷脂、聚乙二醇磷脂、叶酸-聚乙二醇磷脂、聚集诱导发光分子2TT-oC26B为原料,采用纳米沉淀法合成叶酸靶向纳米探针FA-DSPE-PEG-AIE@NPs,对其进行基本表征。选取PC3人前列腺癌细胞、人脐静脉内皮细胞为实验对象,检测纳米探针FA-DSPE-PEG-AIE@NPs的细胞毒性与光照毒性;选取PC3人前列腺癌细胞为实验对象,采用流式细胞术和钙黄绿素/碘化丙啶染色法检测该纳米探针的光热治疗效果。选取BALB/C裸鼠腹部皮下注射PC3人前列腺癌细胞建立肿瘤模型,尾静脉注射纳米探针FA-DSPE-PEG-AIE@NPs后立即对小鼠进行近红外二区荧光成像,12 h后激光照射肿瘤5 min,14 d内观察光热治疗效果。结果与结论:①纳米探针FA-DSPE-PEG-AIE@NPs呈球形,平均粒径(171.0±0.3)nm,具有广谱光吸收能力和延伸至近红外二区的尾部发射,在激光辐照下可发出明亮的近红外二区荧光信号;②纳米探针FA-DSPE-PEG-AIE@NPs的细胞毒性低、光毒性高;流式细胞术及钙黄绿素/碘化丙啶染色法显示,纳米探针FA-DSPE-PEG-AIE@NPs对PC3人前列腺癌细胞具有明显的光热杀伤效果;③纳米探针FA-DSPE-PEG-AIE@NPs成功实现了对活体小鼠血管的近红外二区荧光成像,并确认了在肿瘤部位的最大富集时间为12 h,估算后肢腿部及腹部单根血管的血管宽度分别为0.63 mm和0.42 mm,治疗后14 d小鼠肿瘤体积明显减小;④结果表明,纳米探针FA-DSPE-PEG-AIE@NPs能有效实现前列腺癌的近红外二区荧光成像及光热治疗,有望为前列腺癌的早期诊断及联合治疗提供新手段。

BACKGROUND:A novel aggregation induced luminescence fluorescence probe based on the mechanism of intramolecular motility restriction can be used for the detection of disease markers,tumor diagnosis,and bacterial imaging recognition.OBJECTIVE:To prepare a near-infrared II nanoprobe called FA-DSPE-PEG-AIE@NPs based on aggregation-induced luminescence,and to explore its potential of targeted fluorescence imaging and photothermal therapy for prostate cancer.METHODS:Lecithin,polyethylene glycol phospholipids,folate polyethylene glycol phospholipids,and aggregation induced luminescent molecule 2TT-oC26B were used as raw materials.The folate-targeted nanoprobe FA-DSPE-PEG-AIE@NPs were prepared by nanoprecipitation method,and basic characterization of the nanoprobe was detected.PC3 human prostate cancer cells and human umbilical vein endothelial cells were selected as experimental objects.The cytotoxicity and phototoxicity of FA-DSPE-PEG-AIE@NPs were detected.PC3 human prostate cancer cells were selected as the experimental objects.Flow cytometry and calcein/propidium iodide staining were used to assess the efficacy of photothermal therapy.PC3 human prostate cancer cells were injected subcutaneously into the abdomen of BALB/C nude mice to establish a tumor model,and nanoprobes FA-DSPE-PEG-AIE@NPs were injected into the tail vein.The mice were immediately subjected to near-infraced II fluorescence imaging.12 hours later,the tumor was irradiated by laser for 5 minutes,and the photothermal treatment effect was observed within 14 days.RESULTS AND CONCLUSION:(1)The nanoprobes FA-DSPE-PEG-AIE@NPs with a mean diameter of(171.0±0.3)nm showed a well-defined spherical morphology.The nanoprobe had a wide absorption spectrum and tail emission extending to the near-infrared II which emitted a bright near-infrared II fluorescence signal under laser irradiation.(2)The nanoprobes FA-DSPE-PEG-AIE@NPs had low cytotoxicity and high phototoxicity.The results of flow cytometry and calcein/propidium iodide staining showed that nanoprobes FA-DSPE-PEG-AIE@NPs had an obvious photothermal killing effect on human prostate cancer cells.(3)The nanoprobes FA-DSPE-PEG-AIE@NPs successfully achieved near-infrared II fluorescence imaging of mouse blood vessels and the maximum enrichment time of the tumor was 12 hours.The vessel widths of the hind leg and single blood vessels of abdomen were estimated to be 0.63 mm and 0.42 mm.The tumor volume of mice was significantly smaller after 14 days of treatment.(4)The results show that nanoprobes FA-DSPE-PEG-AIE@NPs can achieve near-infrared II fluorescence imaging and photothermal therapy of prostate cancer effectively,which may provide a new method for early diagnosis and combined treatment of prostate cancer.