Quantitative Structure-Activity Relationship Study of Histone Deacetylase Inhibitors

Histone deacetylases (HDACs) play a critical role in gene transcription and have become a novel target for the discovery of drugs against cancer and other diseases. During the past several years there have been extensive efforts in the identification and optimization of histone deacetylase inhibitors (HDACIs) as novel anticancer drugs. Here we report a comprehensive quantitative structure-activity relationship (QSAR) study of HDACIs in the hope of identifying the structural determinants for anticancer activity. We have identified, collected, and verified the structural and biological activity data for 124 compounds from various literature sources and performed an extensive QSAR study on this comprehensive data set by using various QSAR and classification methods. A highly predictive QSAR model with R2 of 0.76 and leave-one-out cross-validated R2 of 0.73 was obtained. The overall rate of cross-validated correct prediction of the classification model is around 92%. The QSAR and classification models provided direct guidance to our internal programs of identifying and optimizing HDAC inhibitors. Limitations of the models were also discussed. Keywords: histone deacetylases (hdacs), hdac inhibitors, crystallographic data, histone deacetylases-like protein (hdlp), molecular structural descriptors, quantitative structure-activity relationship (qsar), classification method, pharmacophore