Discovery of proqodine A derivatives with antitumor activity targeting NAD(P)H: quinone oxidoreductase 1 and nicotinamide phosphoribosyltransferase.

NAD(P)H: quinone oxidoreductase 1 (NQO1) is a flavin protease highly expressed in various cancer cells. NQO1 catalyzes a futile redox cycle in substrates, leading to substantial reactive oxygen species (ROS) production. This ROS generation results in extensive DNA damage and elevated poly (ADP-ribose) polymerase 1 (PARP1)-mediated consumption of nicotinamide adenine dinucleotide (NAD+), ultimately causing cell death. Nicotinamide phosphoribosyltransferase (NAMPT), the rate-limiting enzyme in the NAD+ salvage synthesis pathway, emerges as a critical target in cancer therapy. The concurrent inhibition of NQO1 and NAMPT triggers hyperactivation of PARP1 and intensive NAD+ depletion. In this study, we designed, synthesized, and assessed a novel series of proqodine A derivatives targeting both NQO1 and NAMPT. Among these, compound T8 demonstrated potent antitumor properties. Specifically, T8 selectively inhibited the proliferation of MCF-7 cells and induced apoptosis through mechanisms dependent on both NQO1 and NAMPT. This discovery offers a promising new molecular entity for advancing anticancer research.

Selective Photoaffinity Probe for Monitoring Farnesoid X Receptor Expression in Cultured Cells.

Farnesoid X receptor (FXR), a member of the nuclear receptor superfamily, is a vital ligand-activated transcriptional factor, which is highly expressed in the liver, intestine, and adrenal gland. However, FXR homeostasis is influenced by many factors, such as diet and circadian rhythm, and the expression of FXR differs in diverse organs. Currently, there is no method to monitor the FXR homeostasis in real time, which restricts us from further investigating the function of FXR under physiological and pathological conditions. In this project, classic FXR agonists were selected to be modified to targeting FXR. The photo-cross-linking diazirine group and alkynyl, a click reaction group, were incorporated to the ligands. Through biorthogonal reaction, fluorophore was linked to the ligands to realize the monitoring of FXR expression in cells.