Abstract
Machine learning techniques have been widely used in drug discovery and development, particularly in the areas of cheminformatics, bioinformatics and other types of pharmaceutical research. It has been demonstrated they are suitable for large high dimensional data, and the models built with these methods can be used for robust external predictions. However, various problems and challenges still exist, and new approaches are in great need. In this Chapter, the authors will review the current development of machine learning techniques, and especially focus on several machine learning techniques they developed as well as their application to model building, lead discovery via virtual screening, integration with molecular docking, and prediction of off-target properties. The authors will suggest some potential different avenues to unify different disciplines, such as cheminformatics, bioinformatics and systems biology, for the purpose of developing integrated in silico drug discovery and development approaches.
TopIntroduction
Drug discovery and development is regarded as one of the most complex research areas encompassing many disciplines (Cohen et al., 2004; Gomeni et al., 2001; Martin, 1991; Tropsha & Zheng, 2001). This might be part of the reasons why it is extremely expensive and time-consuming, and why the current pharmaceutical business is hitting a wall with its severely stalled discovery engine (Tralau-Stewart et al., 2009). In seeking efficient and costly effective approaches, computer-aided methods are gaining more and more attentions, and recent years have witnessed dramatic progress in computer-aided drug design (Cohen et al., 2004; Gomeni et al., 2001; Martin, 1991; Tropsha & Zheng, 2001). This is partially due to the significant advances in the analysis of explosively growing biological and chemical data using modern machine learning techniques (Mitchell et al., 1989; Mjolsness & DeCoste, 2001; Schneider & Downs, 2003). Machine learning has been referred to the development of algorithms that improve their performance in pattern recognition, classification, regression and prediction based on the models derived from existing data. Therefore, it is closely related to fields such as data mining, pattern recognition, theoretical computer science, and many other areas (Mitchell et al., 1989). For instance, algorithms for classification have been used frequently to identify active and inactive compounds, while regression approaches are applied to the training and prediction of continuous data. Despite being widely used in other biomedical research such as bioinformatics, we will focus herein on its application to small molecule drug discovery and development.