Near-infrared (NIR) photothermal therapy plays a critical role in the cancer treatment and diagnosis as a promising carcinoma treatment modalities nowadays. However, development of clinical application has been greatly limited due to the inefficient drug release and low tumor accumulation. Herein, we designed a NIR-light triggered indocyanine green (ICG)-based PCL core/P(MEO₂MA-b-HMAM) shell nanocomposites (PPH@ICG) and evaluated their therapeutic effects in vitro and in vivo. The anticancer drug 5-fluorouracil (5Fu) and the photothermal agent ICG were loaded into a thermo-sensitive micelle (PPH@5Fu@ICG) by self-assembly. The nanoparticles formed were characterized using transmission electron microscopy, dynamic light scattering, and fluorescence spectra. The thermo-sensitive copolymer (PPH@5Fu@ICG) showed a great temperature-controlled drug release response with lower critical solution temperature. In vitro cellular uptake and TEM imaging proved that PPH@5Fu@ICG nanoparticles can home into the lysosomal compartments under NIR. Moreover, in gastric tumor-bearing nude mice, PPH@5Fu@ICG + NIR group exhibited excellent improvement in antitumor efficacy based on the NIR-triggered thermo-chemotherapy synergy, both in vitro and in vivo. In summary, the proposed strategy of synergistic photo-hyperthermia chemotherapy effectively reduced the 5Fu dose, toxic or side effect, which could serve as a secure and efficient approach for cancer theranostics.

中文翻译：

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用于近红外光的光热响应治疗诊断纳米复合材料触发药物释放并增强光热化疗对胃癌的协同作用

近红外 (NIR) 光热疗法作为当今有前途的癌症治疗方式，在癌症治疗和诊断中起着至关重要的作用。然而，由于药物释放效率低和肿瘤蓄积低，临床应用的发展受到很大限制。在此，我们设计了一种基于 NIR 光触发的吲哚菁绿 (ICG) 的 PCL 核/P(MEO ₂ MA- b-HMAM) 壳纳米复合材料 (PPH@ICG) 并评估了它们在体外和体内的治疗效果。通过自组装将抗癌药物5-氟尿嘧啶（5Fu）和光热剂ICG负载到热敏胶束（PPH@5Fu@ICG）中。使用透射电子显微镜、动态光散射和荧光光谱对形成的纳米颗粒进行表征。热敏共聚物（PPH@5Fu@ICG）表现出良好的温控药物释放响应和较低的临界溶解温度。体外细胞摄取和 TEM 成像证明 PPH@5Fu@ICG 纳米粒子可以在 NIR 下归巢到溶酶体隔室中。此外，在荷瘤裸鼠中，PPH@5Fu@ICG + NIR 组基于 NIR 触发的热化疗协同作用表现出优异的抗肿瘤疗效，体外和体内。综上所述，所提出的协同光热疗策略有效降低了 5Fu 的剂量、毒副作用，可作为一种安全有效的癌症治疗方法。