Polydopamine‐Engineered Theranostic Nanoscouts Enabling Intracellular HSP90 mRNAs Fluorescence Detection for Imaging‐Guided Chemo–Photothermal Therapy

The combination of photothermal therapy (PTT) and chemotherapy is considered a promising tumor treatment modality, nevertheless, cellular resistance induced by heat shock proteins (HSPs) overexpressed in tumor cells will restrict the therapeutic effect. Herein, a multifunctional nanobeacon DOX/HCuS@PDA-MB (D/CP-MB) with a scout function for HSP90 mRNA fluorescence detection and near-infrared (NIR) triggered drug release for sensitizing chemo-photothermal therapy, is proposed. In the theranostic nanobeacons, HSP90MBs not only enable fluorescence detection of intracellular HSP90 mRNAs, but also downregulate the expression of HSP90 to reduce cell resistance. With the assistance of NIR and guidance of fluorescence imaging, spatiotemporal doxorubicin release can be achieved by the trigger of the photothermal effect, allowing for combined chemotherapy and photothermal treatment. Furthermore, the dual photothermal effect of hollow mesoporous CuS (HCuS) and polydopamine will lead to a better photothermal effect. Moreover, compared with other control groups, D/CP-MB nanobeacons exhibit effective boost therapeutic efficacy by inducing significant suppression of tumor proliferation and enhancement of apoptosis both in vitro and in vivo. In summary, this work provides novel theranostic nanobeacons that integrate imaging and therapy in a single nanoparticle, this strategy of imaging-guided therapy can enable precise tumor treatment and effectively improve tumor treatment efficacy.