兰州大学机构库 >口腔医学院
聚多巴胺和MnO2修饰紫杉醇碳量子点协同治疗口腔鳞状细胞癌的体外研究
Alternative TitleSynergistic treatment of squamous cell carcinoma with polydopamine and mno2-modified paclitaxel carbon dots
陈李鑫
Subtype硕士
Thesis Advisor何等旗 ; 周平
2023-05-28
Degree Grantor兰州大学
Place of Conferral兰州
Degree Name医学硕士
Degree Discipline口腔医学
Keyword碳点 Carbon dots 紫杉醇 Paclitaxel 聚多巴胺 polydopamine 二氧化锰 Manganese dioxide 光热治疗 Photothermal therapy 响应释放 TME-sensitive release
Abstract

背景:头颈部癌症是世界第六大恶性肿瘤,在全球范围内所报告的头颈部癌症病例中,口腔鳞状细胞癌(Oral squamous cell carcinoma, OSCC)是较为常见的一种。化学药物疗法是治疗恶性肿瘤的三大手段之一,但绝大多数化疗药物都存在靶向性差、不良反应严重、治疗指数低等缺点,使用纳米载体技术提高抗肿瘤药物的递送效果是提升化疗疗效的有效策略。紫杉醇(Paclitaxel, PTX)作为治疗头颈部癌症的最常见药物之一,由于水溶性极低,生物利用度差,常使用聚氧乙烯蓖麻油(Cremophor EL)和乙醇作为赋形剂,克服在肠外使用时溶解度低的问题。然而聚氧乙烯蓖麻油并不是无害的,它常常与严重的过敏样超敏反应、高脂血症、脂蛋白异常、红细胞聚集和周围神经病变有关。因此,以PTX为基础设计新的碳基纳米材料,改善其水溶性、生物利用度和靶向性具有重要的临床意义和实用价值。

目的:本研究以PTX为核心碳源,通过一步水热法合成紫杉醇来源的碳量子点(Paclitaxel carbon dots, PCDs),合成的PCDs不仅保留了部分肿瘤杀伤特性,且具备极其良好的水溶性及生物安全性,在抗肿瘤应用过程中不再需要添加聚氧乙烯蓖麻油等表面活性剂,大大提高了安全性,减小了患者负担。以聚多巴胺(Polydopamine, PDA)和MnO2来修饰PCDs,使PCDs纳米复合物获得PDA的光热特性及对模拟肿瘤微环境(Tumor microenvironment, TME)的响应释放特性。该合成的新型纳米颗粒同时具备高生物相容性,高靶向性,低副作用及多肿瘤治疗策略结合的优势,解决临床现有紫杉醇制剂的缺点。

方法:通过一步水热法合成PCDs,利用透射电子显微镜(Transmission electron microscope, TEM)、Zeta电位及粒度分析仪、紫外可见光分光光度计和荧光分光光度计对PCDs的物理特性进行表征,分别在不同pH的溶液中和日光照射下长时间放置观察PCDs的pH稳定性和长期贮存稳定性,通过CCK8法分别以小鼠上皮样成纤维细胞L929细胞和人舌鳞癌细胞Cal-27细胞为模型检测PCDs的生物相容性和抗肿瘤特性,以激光共聚焦显微镜研究PCDs对肿瘤细胞的荧光生物标记特性。以PCDs为基础,通过碱性条件下聚合和超声还原法在PCDs表面修饰PDA和MnO2,通过TEM观察纳米复合物的形貌和尺寸,以高谷胱甘肽(Glutathione, GSH)和低pH模拟肿瘤微环境,研究其对模拟肿瘤微环境的响应释放。在近红外(Near infrared, NIR)的808 nm激光照射下通过红外观测仪测量其温度,研究其光热性能。最后以Cal-27细胞为模型,分别研究不同浓度的PCDs、PCDs@PDA@MnO2及PCDs@PDA@MnO2+ NIR的肿瘤杀伤效果。

结果:TEM显示PCDs在溶液中分散均匀,无明显的团聚现象,平均粒径为2.25 nm,Zeta电位分析仪显示PCDs的Zeta电位为+27.21 mV,PCDs的特征吸收峰为353 nm,而PCDs可以在360 nm激光处获得最佳的激发,其激发光是以450 nm为中心的明亮蓝色荧光。PCDs在pH=3至pH=9的范围内和长时间贮存下保持着较强的发光稳定性。当较大的PCDs浓度作用时(100 μg/mL),L929仍具备较强的细胞活性(80%以上);不同浓度的PTX和PCDs分别作用于Cal-27时,PCDs可以达到PTX的55%-60%的抗肿瘤效果。以PCDs为基础合成PCDs@PDA@MnO2,通过TEM观察PCDs@PDA@MnO2的形貌,PCDs@PDA@MnO2呈现出均匀的球形,可以观察到明显的双层壳层结构,其内层第一层壳层即为PDA,其外层第二层壳层即为MnO2。PCDs@PDA水溶液在808 nm激光照射下的升温效率随着PCDs@PDA浓度的增加而增加(0.5 mg/mL最高);多个循环的循环升降温实验证明PCDs@PDA的光热稳定性良好。PCDs@PDA@MnO2可以对低pH、高GSH和NIR激光照射的环境做出多重响应,释放出壳层内的PCDs@PDA。与PCDs组相比,PCDs@PDA@MnO2组的抗肿瘤活性明显增强,而在808 nm激光的照射下,PCDs@PDA@MnO2+ NIR组的肿瘤杀伤作用得到更进一步的增强。

结论:本研究以PTX为核心碳源,通过一步水热法合成紫杉醇来源的PCDs,PCDs具备极其良好的水溶性、生物安全性及肿瘤细胞荧光标记特性,且保留了部分抗肿瘤活性。以PCDs为基础合成的PCDs@PDA@MnO2可以对肿瘤微环境和NIR激光照射做出多重响应,从而在肿瘤区域内靶向释放出壳层内的PCDs@PDA,壳层内的PCDs@PDA可以在808 nm激光照射下利用光热效应杀伤肿瘤,同时释放出具有抗肿瘤活性的PCDs。本研究证明将具有药理活性的传统抗肿瘤药物PTX与纳米科学技术相结合,将肿瘤微环境响应的化疗与光热治疗(Photothermal therapy, PTT)相结合,是一种有效的治疗策略,可以显著增加对舌鳞癌细胞的杀伤作用,增强靶向性,降低副作用,具有重要的临床意义和实用价值。

Other Abstract

BACKGROUND: Oral squamous cell carcinoma (OSCC) is one of the most common type of head and neck cancer reported worldwide, and is known as "oral cancer". Chemotherapy is one of the three major treatments for malignant tumors, but most chemotherapeutic drugs have poor targeting, serious adverse effects, and low therapeutic index, etc. The use of nanocarrier technology to improve the delivery of antitumor drugs is an effective strategy to enhance the efficacy of chemotherapy. Paclitaxel (PTX), one of the most common drugs for the treatment of head and neck cancer, often uses polyoxyethylene castor oil (Cremophor EL) and ethanol as excipients to overcome the problem of low solubility when used parenterally due to its extremely low water solubility and poor bioavailability. However, polyoxyethylene castor oil is not harmless and is often associated with severe allergy-like hypersensitivity reactions, hyperlipidemia, lipoprotein abnormalities, erythrocyte aggregation, and peripheral neuropathy. Therefore, the design of new carbon-based nanomaterials based on PTX to improve their water solubility, bioavailability and targeting is of great clinical significance and practical value.

OBJECTIVES: In this study, PTX was used as the core carbon source to synthesize PTX-derived carbon dots (Paclitaxel carbon dots, PCDs) by a one-step hydrothermal method. The synthesized PCDs not only retain some of the tumor-killing properties, but also have excellent water solubility and biosafety, which eliminates the need to add surfactants such as polyoxyethylene castor oil during antitumor application. This greatly improves the safety and reduces the burden on patients. By modifying PCDs with polydopamine and MnO2, the PCDs nanocomplexes obtained the photothermal properties of polydopamine and the controlled release properties of tumor microenvironment. The synthesized novel nanoparticles possess the advantages of high biocompatibility, high targeting, low side effects and combination of multiple tumor treatment strategies at the same time, addressing the shortcomings of existing clinical paclitaxel formulations.

METHODS: PCDs were synthesized by one-step hydrothermal method, and the physical properties of PCDs were characterized by transmission electron microscope (TEM), zeta potential and particle size analyzer, UV-Vis spectrophotometer and fluorescence spectrophotometer, and placed in different pH solutions and under sunlight irradiation for a long time, respectively. The pH stability and long-term storage stability of PCDs were observed, and the biocompatibility and anti-tumor properties of PCDs were examined by CCK8 method using L929 cells and Cal-27 cells, respectively. The PCDs were modified by polymerizing dopamine under alkaline conditions and synthesizing MnO2 on the surface of PCDs by ultrasonic reduction. The morphology and size of the PCDs nanocomplexes were observed by TEM, and their release in response to the tumor microenvironment was studied by simulating the tumor microenvironment with high glutathione (GSH) and low pH. The photothermal properties were studied by measuring their temperature by infrared observer under the irradiation of 808 nm laser. Finally, Cal-27 cells were used as a model to study the tumor killing effect of different concentrations of PCDs, PCDs@PDA@MnO2 and PCDs@PDA@MnO2+ NIR, respectively.

RESULTS: TEM showed that the PCDs were uniformly dispersed in anhydrous ethanol solution without obvious agglomeration, and the size distribution was relatively consistent with an average particle size of 2.25 nm. The zeta potential analyzer showed that the zeta potential of PCDs was +27.21 mV, and the characteristic absorption peak of PCDs was 353 nm, while PCDs could obtain the best excitation at 360 nm laser, and their excitation light was PCDs maintain a strong luminescence stability in the range of pH=3 to pH=9, and the luminescence efficiency does not change significantly when they are subjected to natural light irradiation for a long time. When larger concentrations of PCDs were applied (100 μg/mL), mouse epithelial-like fibroblasts L929 still possessed strong cellular activity (more than 80%); when different concentrations of PTX and PCDs were applied to human tongue squamous carcinoma cells Cal-27, respectively, PCDs could achieve 55%-60% of the antitumor effect of PTX. PCDs@PDA@MnO2 was synthesized based on PCDs, and the morphology of PCDs@PDA@MnO2 was observed by TEM. PCDs@PDA@MnO2 showed a uniform spherical shape, and an obvious bilayer shell structure could be observed, the first inner shell layer was PDA, and the second outer shell layer was MnO2. The warming efficiency of PCDs@PDA aqueous solution under 808 nm laser irradiation increased with the increase of PCDs@PDA concentration, and the highest warming efficiency was achieved at 0.5 mg/mL of PCDs@PDA aqueous solution; multiple cycles of cyclic warming experiments demonstrated the good photothermal stability of PCDs@PDA. The irradiated environment responded multiply to release the PCDs@PDA within the shell layer for the next photothermal treatment. The anti-tumor activity of the PCDs@PDA@MnO2 group was significantly enhanced compared to the PCDs group, and the tumor-killing effect of the PCDs@PDA@MnO2+ NIR group was further enhanced under 808 nm laser irradiation.

CONCLUSION: In this study, paclitaxel-derived PCDs were synthesized by a one-step hydrothermal method using PTX as the core carbon source, which possesses extremely good water solubility and biosafety, and retains some anti-tumor activity. The PCDs@PDA@MnO2 synthesized based on PCDs can respond to the tumor microenvironment and NIR laser irradiation in multiple ways, thus targeting the release of PCDs@PDA within the shell layer in the tumor region, and the PCDs@PDA within the shell layer can kill the tumor with photothermal therapy under 808 nm laser excitation, while releasing PCDs with antitumor activity. this study demonstrated that combining PTX, a traditional antitumor drug with pharmacological activity, with nanoscience and technology, and combining chemotherapy with photothermal therapy is an effective therapeutic strategy that can significantly increase the killing effect on tongue squamous cancer cells, enhance targeting and reduce side effects, with important clinical significance and practical value.

MOST Discipline Catalogue医学 - 口腔医学
URL查看原文
Language中文
Other Code262010_220200926561
Document Type学位论文
Identifierhttps://ir.lzu.edu.cn/handle/262010/537649
Collection口腔医学院
Affiliation
兰州大学口腔医学院
Recommended Citation
GB/T 7714
陈李鑫. 聚多巴胺和MnO2修饰紫杉醇碳量子点协同治疗口腔鳞状细胞癌的体外研究[D]. 兰州. 兰州大学,2023.
Files in This Item:
There are no files associated with this item.
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Altmetrics Score
Google Scholar
Similar articles in Google Scholar
[陈李鑫]'s Articles
Baidu academic
Similar articles in Baidu academic
[陈李鑫]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[陈李鑫]'s Articles
Terms of Use
No data!
Social Bookmark/Share
No comment.
Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.