Development of zinc protoporphyrin micelles for cancer photodymanic therapy with xenon light

本研究通过比较不同ZnPP胶束的理化特性、稳定性以及体内药代动力学，发现粒径约为80 nm的HPMA-ZnPP在循环中表现出良好的稳定性，导致血浆半衰期延长以及肿瘤选择性蓄积（EPR效应）。因此，我们选择HPMA-ZnPP进行进一步开发。使用Hela细胞的体外研究在光照射时表现出HPMA-ZnPP的强细胞毒性。体内实验显示HPMA-ZnPP对肿瘤生长的剂量依赖性和辐射依赖性（强度和持续时间）抑制。此外，在体内成像系统中清楚地检测到HPMA-ZnPP的肿瘤选择性积累。总之，这些发现强烈表明HPMA-ZnPP作为一种新的PDT癌症药物的潜力，同时具有肿瘤检测效力。

In this study, by comparing the physiochemical characteristics, stability as well as in vivo pharmacokinetics of different ZnPP micelles, we found that HPMA-ZnPP, with the particle size of about 80 nm, showed good stability in circulation, resulting in prolonged plasma half-life as well as tumor-selective accumulation (EPR effect). We thus selected HPMA-ZnPP for further development. In vitro studies using Hela cells exhibited a strong cytotoxicity of HPMA-ZnPP upon light irradiation. In vivo experiments showed an HPMA-ZnPP dose-dependent and irradiation dependent (intensity and duration) suppression of tumor growth. Moreover, the tumor-selective accumulation of HPMA-ZnPP was clearly detected in an in vivo imaging system. Token together, these findings strongly suggest the potential of HPMA-ZnPP as a new PDT drug for cancer, at the same time with tumor-detecting potency.