Molecular-engineered highly photosensitive triarylphosphine oxide compounds for apoptosis imaging and selectively inducing apoptosis of tumor cells by photodynamic therapy

Lysophosphatidic acid responsive photosensitive supramolecular organic frameworks for tumor imaging, drug loading, and photodynamic therapy

Supramolecular organic frameworks have been widely applied for biological detection and drug delivery. In this study, a supramolecular organic framework (SOF) is constructed through the self-assembly of a highly photosensitive triarylphosphine oxide guest molecule, OTPP-6-Methyl, with cucurbit [8] uril (CB [8]). The formation of the SOF gradually enhances the weak fluorescence of OTPP-6-Methyl owing to the restriction of the molecular folding motion. Although the high positive charge of OTPP-6-Methyl facilitates binding to various negatively charged substances, the SOF system only demonstrated an obvious fluorescence response to LPA, a biomarker of ovarian cancer, via the disassembly of SOF and subsequent binding of OTPP-6-Methyl with LPA. The fluorescence changes during the entire process are insufficient to allow the sensitive detection of LPA; thus, we further designed a FRET system by introducing Cy5, which can act as an energy receptor to achieve a ratiometric readout for LPA. The tumor-targeting cRGD group was introduced into the SOF system as part of another guest molecule, OTPP-5-M-1-cRGD, to improve the tumor-targeting ability of the SOF system. The SOF system further improves the photosensitivity of guest molecules, and is therefore used in the in vivo imaging of ovarian cancer subcutaneous tumors and as a DDS for loading DOX for the combined in vivo chemotherapy and photodynamic treatment of tumors.

An ER-targeted, Viscosity-sensitive Hemicyanine Dye for the Diagnosis of Nonalcoholic Fatty Liver and Photodynamic Cancer Therapy by Activating Pyroptosis Pathway

The concept of molecular design, integrating diagnostic and therapeutic functions, aligns with the general trend of modern medical advancement. Herein, we rationally designed the smart molecule ER-ZS for endoplasmic reticulum (ER)-targeted diagnosis and treatment in cell and animal models by combining hemicyanine dyes with ER-targeted functional groups (p-toluenesulfonamide). Owing to its ability to target the ER with a highly specific response to viscosity, ER-ZS demonstrated substantial fluorescence turn-on only after binding to the ER, independent of other physiological environments. In addition, ER-ZS, being a small molecule, allows for the diagnosis of nonalcoholic fatty liver disease (NAFLD) via liver imaging based on high ER stress. Importantly, ER-ZS is a type I photosensitizer, producing O2 ⋅- and ⋅OH under light irradiation. Thus, after irradiating for a certain period, the photodynamic therapy inflicted severe oxidative damage to the ER of tumor cells in hypoxic (2 % O2 ) conditions and activated the unique pyroptosis pathway, demonstrating excellent antitumor capacity in xenograft tumor models. Hence, the proposed strategy will likely shed new light on integrating molecular optics for NAFLD diagnosis and cancer therapy.