Tumor penetration of nanocarriers is still an unresolved challenge for effective drug delivery. Herein, we described a size-switchable nanoplatform in response to an external near-infrared (NIR) laser for transcellular drug delivery. The nanoplatform was constructed with a poly(N-isopropylacrylamide) (PNIPAM)-based nanogel encapsulating chitosan-coated single-walled carbon nanotubes, followed by loading a chemotherapeutic drug, doxorubicin (DOX). In mice bearing orthotopic breast tumors, the photothermal effect from single-walled carbon nanotubes upon NIR irradiation potently inhibited tumor growth. The antitumor effect of the nanomedicine with NIR irradiation might be attributed to its capability of transcellular transport and tumor penetration in mice. In addition, the nanomedicine with NIR irradiation could elicit an antitumor response by increasing cytotoxic T cells and decreasing myeloid-derived suppressor cells. These results validated the application of photo/thermo-responsive nanomedicine in the orthotopic model of breast cancer.

中文翻译：

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用于原位乳腺癌化学光热疗法的光/热响应和尺寸可切换纳米粒子

纳米载体的肿瘤渗透仍然是有效药物递送的未解决挑战。在这里，我们描述了一种尺寸可切换的纳米平台，以响应用于跨细胞药物递送的外部近红外 (NIR) 激光。纳米平台由聚（N-异丙基丙烯酰胺）（PNIPAM）基纳米凝胶包裹壳聚糖涂层的单壁碳纳米管，然后加载化疗药物阿霉素（DOX）。在患有原位乳腺肿瘤的小鼠中，单壁碳纳米管在 NIR 照射下的光热效应有效地抑制了肿瘤的生长。近红外照射纳米药物的抗肿瘤作用可能归因于其在小鼠体内的跨细胞转运和肿瘤穿透能力。此外，具有近红外辐射的纳米药物可以通过增加细胞毒性 T 细胞和减少骨髓来源的抑制细胞来引发抗肿瘤反应。这些结果验证了光/热响应纳米药物在乳腺癌原位模型中的应用。