Benito-Miguel Marta, Blanco M Dolores, Gómez Clara
Centro Universitario San Rafael-Nebrija, Madrid, Spain; Departamento de Bioquímica y Biología Molecular III, Facultad de Medicina, UCM, Madrid, Spain.
Departamento de Bioquímica y Biología Molecular III, Facultad de Medicina, UCM, Madrid, Spain.
Photodiagnosis Photodyn Ther. 2015 Sep;12(3):466-75. doi: 10.1016/j.pdpdt.2015.05.001. Epub 2015 May 12.
Natural polymers are used as components of nanoparticles (NPs) for drug delivery, as they provide targeted, sustained release and biodegradability. The purpose of this study was to increase the efficacy of the photodynamic therapy (PDT) by the combination of 5-aminolevulinic acid (ALA) with 5-fluorouracil-loaded-chitosan-nanoparticles (5-Fu-CNPs).
Nanoparticles based on chitosan (CNPs) were synthesized by the ionic crosslinking method via the TPP addition. 5-Fluorouracil (5-Fu), a first-line anticancer drug, was loaded into these 5Fu-CNPs, and they were assayed as controlled delivery formulation. HeLa cells were incubated in the presence of 5Fu-CNPs for 24h, next ALA was added to the culture medium and 4h later, to complete the PDT, light irradiation took place. Analysis of cell viability, reactive oxygen species (ROS) production, observation of the apoptosis by fluorescence microscopy followed by analysis of caspase-3 activity were carried out.
Spherical 5Fu-CNPs with a mean diameter of 324±43nm, were successfully synthesized and characterized by TEM and DLS. 5-Fu incorporation was achieved successfully (12.3μg 5Fu/mg CNP) and the maximum 5-Fu release took place at 2h. The combined administration of 5Fu-CNPs and PDT mediated by ALA (ALA-PDT) led to an improved efficacy of the antineoplastic treatment by generation of great cytotoxicity inducted through an increased ROS production. HeLa cells were destroyed by apoptosis through activation of caspase pathway.
This study proves that combination therapy (photodynamic "ALA"+chemical "5-Fu"+immunoadjuvant "chitosan") may be an effective approach for the treatment of cancer.
天然聚合物被用作纳米颗粒（NPs）的药物递送成分，因为它们具有靶向性、缓释性和生物可降解性。本研究的目的是通过将5-氨基酮戊酸（ALA）与负载5-氟尿嘧啶的壳聚糖纳米颗粒（5-Fu-CNPs）相结合来提高光动力疗法（PDT）的疗效。
通过添加三聚磷酸钠（TPP）的离子交联法合成基于壳聚糖的纳米颗粒（CNPs）。将一线抗癌药物5-氟尿嘧啶（5-Fu）负载到这些5-Fu-CNPs中，并将它们作为控释制剂进行检测。将HeLa细胞在5-Fu-CNPs存在的情况下孵育24小时，然后向培养基中加入ALA，4小时后进行光照以完成PDT。进行细胞活力分析、活性氧（ROS）生成分析、通过荧光显微镜观察细胞凋亡，随后分析caspase-3活性。
成功合成了平均直径为324±43nm的球形5-Fu-CNPs，并通过透射电子显微镜（TEM）和动态光散射（DLS）对其进行了表征。成功实现了5-Fu的负载（12.3μg 5-Fu/mg CNP），且5-Fu在2小时时达到最大释放量。5-Fu-CNPs与ALA介导的PDT（ALA-PDT）联合给药通过增加ROS生成诱导产生更大的细胞毒性，从而提高了抗肿瘤治疗的疗效。HeLa细胞通过激活caspase途径被凋亡破坏。
本研究证明联合治疗（光动力“ALA”+化学“5-Fu”+免疫佐剂“壳聚糖”）可能是一种有效的癌症治疗方法。
