Ali Safdar, Majid Abdul
Department of Computer & Information Sciences, Pakistan Institute of Engineering & Applied Sciences, Nilore, 45650 Islamabad, Pakistan.
J Biomed Inform. 2015 Apr;54:256-69. doi: 10.1016/j.jbi.2015.01.004. Epub 2015 Jan 21.
The diagnostic of human breast cancer is an intricate process and specific indicators may produce negative results. In order to avoid misleading results, accurate and reliable diagnostic system for breast cancer is indispensable. Recently, several interesting machine-learning (ML) approaches are proposed for prediction of breast cancer. To this end, we developed a novel classifier stacking based evolutionary ensemble system "Can-Evo-Ens" for predicting amino acid sequences associated with breast cancer. In this paper, first, we selected four diverse-type of ML algorithms of Naïve Bayes, K-Nearest Neighbor, Support Vector Machines, and Random Forest as base-level classifiers. These classifiers are trained individually in different feature spaces using physicochemical properties of amino acids. In order to exploit the decision spaces, the preliminary predictions of base-level classifiers are stacked. Genetic programming (GP) is then employed to develop a meta-classifier that optimal combine the predictions of the base classifiers. The most suitable threshold value of the best-evolved predictor is computed using Particle Swarm Optimization technique. Our experiments have demonstrated the robustness of Can-Evo-Ens system for independent validation dataset. The proposed system has achieved the highest value of Area Under Curve (AUC) of ROC Curve of 99.95% for cancer prediction. The comparative results revealed that proposed approach is better than individual ML approaches and conventional ensemble approaches of AdaBoostM1, Bagging, GentleBoost, and Random Subspace. It is expected that the proposed novel system would have a major impact on the fields of Biomedical, Genomics, Proteomics, Bioinformatics, and Drug Development.
人类乳腺癌的诊断是一个复杂的过程,特定指标可能会产生阴性结果。为避免产生误导性结果,乳腺癌的准确可靠诊断系统必不可少。最近,人们提出了几种有趣的机器学习(ML)方法用于乳腺癌预测。为此,我们开发了一种基于分类器堆叠的新型进化集成系统“Can-Evo-Ens”,用于预测与乳腺癌相关的氨基酸序列。在本文中,首先,我们选择了朴素贝叶斯、K近邻、支持向量机和随机森林这四种不同类型的ML算法作为基础分类器。这些分类器利用氨基酸的物理化学性质在不同特征空间中分别进行训练。为了利用决策空间,对基础分类器的初步预测结果进行堆叠。然后采用遗传编程(GP)来开发一个元分类器,以优化组合基础分类器的预测结果。使用粒子群优化技术计算最佳进化预测器的最合适阈值。我们的实验证明了Can-Evo-Ens系统对独立验证数据集的稳健性。所提出的系统在癌症预测的ROC曲线下面积(AUC)方面达到了99.95%的最高值。比较结果表明,所提出的方法优于个体ML方法以及AdaBoostM1、Bagging、GentleBoost和随机子空间等传统集成方法。预计所提出的新系统将对生物医学、基因组学、蛋白质组学、生物信息学和药物开发等领域产生重大影响。