Selective BH3 mimetics synergize with BET inhibition to induce mitochondrial apoptosis in rhabdomyosarcoma cells

Targeting the epigenetic reader "BET" as a therapeutic strategy for cancer

Bromodomain and extraterminal (BET) proteins have the ability to bind to acetylated lysine residues present in both histones and non-histone proteins. This binding is facilitated by the presence of tandem bromodomains. The regulatory role of BET proteins extends to chromatin dynamics, cellular processes, and disease progression. The BET family comprises of BRD 2, 3, 4 and BRDT. The BET proteins are a class of epigenetic readers that regulate the transcriptional activity of a multitude of genes that are involved in the pathogenesis of cancer. Thus, targeting BET proteins has been identified as a potentially efficacious approach for the treatment of cancer. BET inhibitors (BETis) are known to interfere with the binding of BET proteins to acetylated lysine residues of chromatin, thereby leading to the suppression of transcription of several genes, including oncogenic transcription factors. Here in this review, we focus on role of Bromodomain and extra C-terminal (BET) proteins in cancer progression. Furthermore, numerous small-molecule inhibitors with pan-BET activity have been documented, with certain compounds currently undergoing clinical assessment. However, it is apparent that the clinical effectiveness of the present BET inhibitors is restricted, prompting the exploration of novel technologies to enhance their clinical outcomes and mitigate undesired adverse effects. Thus, strategies like development of selective BET-BD1, & BD2 inhibitors, dual and acting BET are also presented in this review and attempts to cover the chemistry needed for proper establishment of designed molecules into BRD have been made. Moreover, the review attempts to summarize the details of research till date and proposes a space for future development of BET inhibitor with diminished side effects. It can be concluded that discovery of isoform selective BET inhibitors can be a way forward in order to develop BET inhibitors with negligible side effects.

Double-Sided Nano-ZnO: Superior Antibacterial Properties and Induced Hepatotoxicity in Zebrafish Embryos

Zinc oxide nanoparticles (Nano-ZnO) have been widely used in the food, cosmetics, and biomedical fields due to their excellent antibacterial and antioxidant properties. However, with the widespread application of Nano-ZnO, Nano-ZnO inevitably enters the environment and living organisms, causing harm to human health and ecosystem safety. Therefore, the biosafety and toxicological issues of Nano-ZnO are gradually being emphasized. Our study found that Nano-ZnO has superior antibacterial properties compared to ofloxacin in the fight against Staphylococcus aureus (S. aureus). Given that ofloxacin can inhibit bacterial-induced inflammation, we constructed a model of bacterial inflammation using S. aureus in zebrafish. We found that Nano-ZnO inhibited the NF-κB-mediated inflammatory signaling pathway. However, in the process, we found that Nano-ZnO caused hepatic steatosis in zebrafish. This suggested that Nano-ZnO had a certain hepatotoxicity, but did not affect liver development. Subsequently, we investigated the mechanism of hepatotoxicity produced by Nano-ZnO. Nano-ZnO triggered oxidative stress in the liver by generating ROS, which then induced endoplasmic reticulum stress to occur. It further activated srebp and its downstream genes fasn and acc1, which promoted the accumulation of fatty acid synthesis and the development of steatosis, leading to the development of nonalcoholic fatty liver disease (NAFLD). To address the hepatotoxicity of Nano-ZnO, we added carbon dots for the treatment of NAFLD. The carbon dots were found to normalize the steatotic liver. This provided a new strategy to address the hepatotoxicity caused by Nano-ZnO. In this work, we systematically analyzed the antibacterial advantages of Nano-ZnO in vivo and in vitro, explored the mechanism of Nano-ZnO hepatotoxicity, and proposed a new method to treat Nano-ZnO hepatotoxicity.