Graph Representation Learning for Drug Discovery
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Graph Representation Learning for Drug Discovery Jian Tang Mila-Quebec AI Institute CIFAR AI Research Chair HEC Montreal www.jian-tang.com The Process of Drug Discovery • A very long and costly process • On average takes more than 10 years and $2.5B to get a drug approved Preclinical Lead Discovery Lead Optimization Clinical Target Study 2 years 3 years Trial 2 years Screen millions of Modify the molecule In-vitro and functional molecules; to improve specific in-vivo Multiple Phases Found by serendipity: properties. experiments; Penicillin e.g. toxicity, SA synthesis Molecules Research Problems Lead Lead Preclinical Clinical Target Discovery Optimization Study Trial 2 years 3 years 2 years Molecule Property Prediction Property Molecule Design and Optimization Property Retrosynthesis Prediction + Molecule Properties Prediction • Predicting the properties of molecules or compounds is a fundamental problem in drug discovery • E.g., in the stage of virtual screening • Each molecule is represented as a graph • The fundamental problem: how to represent a whole molecule (graph) Graph Neural Networks • Techniques for learning node/graph representations • Graph convolutional Networks (Kipf et al. 2016) • Graph attention networks (Veličković et al. 2017) • Neural Message Passing (Gilmer et al. 2017) 푘 푘 MESSAGE PASSING: 푀푘(ℎ푣 , ℎ푤, 푒푣푤) w AGGREGATE : 푚푘+1 = AGGREGATE{푀 ℎ푘, ℎ푘 , 푒 : 푤 ∈ 푁 푣 } 푣 푘 푣 푤 푣푤 v 푘+1 푘 푘+1 COMBINE : ℎ푣 = COMBINE(ℎ푣 , 푚푣 ) 퐾 READOUT: 푔 = READOUT{ℎ푣 : 푣 ∈ 퐺} InfoGraph: Unsupervised and Semi-supervised Whole-Graph Representation Learning (Sun et al. ICLR’20) • For supervised methods based on graph neural networks, a large number of labeled data are required for training • The number of labeled data are very limited in drug discovery • A large amount of unlabeled data (molecules) are available • This work: how to effectively learn whole graph representations in unsupervised or semi-supervised fashion Fanyun Sun, Jordan Hoffman, Vikas Verma and Jian Tang. InfoGraph: Unsupervised and Semi-supervised Graph-Level Representation Learning via Mutual Information Maximization. ICLR’20. Figure 1: Illustration of InfoGraph. An input graph isencoded into afeature map by graph convolutions and jumping concatenation. The discriminator takes a(global representation, patchFigurerepresentation)1: Illustrationpairof InfoGraph.as input andAndecidesinput graphwhetherisencoded into afeature map by graph convolutions and jumping they are from the same graph. 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