Noticing that HDAC6/10 degraders AP1-AP6 showed no antiproliferative effects on MM.1S and MCF-7 cells (Table and The first HDAC6 PROTACs were reported by Tang and co-workers in 2018. Interestingly, despite employing a non-selective inhibitor as the HDAC warhead, the authors achieved selective HDAC6 degradation. Since then, various selective HDAC6 degraders have been developed using derivatives of non-selective inhibitors (e.g., crebinostat and vorinostat) , HDAC6-selective inhibitors (e.g., nexturastat A) , and HDAC6/8-selective inhibitors as HDAC recruiters. However, none of these studies have investigated the effects of HDAC6 PROTACs on HDAC10 protein levels. The only available HDAC10 data come from a chemoproteomics study, which reported that certain vorinostatand dacinostat-based PROTACs reduced HDAC10 levels, albeit without selectivity over other isoforms.