BAF inhibitors encompass a range of compounds that, either directly or indirectly, modulate the activity of the BAF complex, a key player in chromatin remodeling and regulation of gene expression. This class of inhibitors primarily includes compounds that target key signaling pathways and enzymatic processes intricately linked to chromatin modification and gene regulation. The first category of BAF inhibitors includes those that target histone modifications directly associated with chromatin structure and accessibility. Compounds like Trichostatin A, Vorinostat, and Panobinostat exemplify this category. These inhibitors, by targeting HDACs, alter the acetylation status of histones, which can indirectly impact BAF complex activity by changing chromatin accessibility and the dynamics of chromatin remodeling. This alteration in chromatin structure is crucial in regulating gene expression, where the BAF complex plays a significant role.
The second category encompasses inhibitors that act on DNA methylation or histone recognition processes, which can indirectly influence BAF activity due to the interconnected nature of chromatin modification mechanisms. 5-Azacytidine and Decitabine, as DNMT inhibitors, fall into this category. By affecting DNA methylation patterns, these compounds can indirectly modulate BAF complex-mediated chromatin remodeling and gene regulation. Similarly, JQ1 and I-BET762, by inhibiting BET bromodomain proteins, alter the reading of acetylated histones, which can influence the BAF complex's role in chromatin dynamics. These inhibitors function by altering the cellular milieu in which the BAF complex operates, thereby influencing its role in chromatin remodeling and gene expression regulation. The mechanisms of action of these compounds, while not directly targeting the BAF complex, can lead to changes in the complex's activity or its functional state, ultimately impacting its role in gene regulation. This indirect approach to inhibiting the BAF complex highlights the complex network of chromatin modification mechanisms that govern gene expression and the ability of targeting these mechanisms to modulate the activity of key complexes like the BAF.