HDAC2 and breast cancer: In 2016, Hati et al. [51] designed and synthesized a library of spiro[pyrrolidine-3,3′-oxindoles] 38a–n (Fig. 11) as potential anti breast cancer agents with a dual activity against histone deacetylase 2 (HDAC2) and prohibitin 2 (PHB2) enzymes.