Highly efficient Chemo/Photothermal therapy alleviating tumor hypoxia against cancer and attenuate liver metastasis in vivo

Tumor metastasis is a major cause of poor cancer prognosis. Photothermal therapy (PTT) is a non-invasive, nonoxygen-dependent, and highly spatiotemporally precise treatment that may aid chemotherapy in suppressing tumor growth and metastasis. This article aims to develop and modify a CuS-based nanoplatform linking RGDAcrk to actively target and internalize doxorubicin (DOX) into tumor cells, resulting in an alternating strategy of synergistic chemo/PTT. The nanoparticle's shape, spectra, drug encapsulation efficiency, loading content, and controlled release are characterized, and a comparison of 808/980 nm lasers is used to irradiate the nanoplatform. The cell survival rate is used to determine the cytotoxicity of DOX and PTT, and the chemo/PTT is used to treat 4T1-Luc tumor-bearing mice. Simultaneously, bioluminescence and photoacoustic imaging are employed to assess therapy efficacy, as well as tumor size, weight, density, the bodyweight of mice, and survival curves. H&E, immunohistochemistry for HIF-1 alpha, and TUNEL fluorescence staining confirm these findings, suggesting that the nanoplatform has a good active-targeted capacity and perform high-efficiency PTT caused by 980 nm laser irradiation. The synergistic effect is at least 3.53 times higher than chemo/PTT without synergistic effect and tumor liver metastasis is successfully suppressed, showing that it has the potential to be used for cancer treatment and prognosis improvement.