title: Informative gene selection and direct classification of tumor based on Chi-square test of pairwise gene interactions.
abstract: In efforts to discover disease mechanisms and improve clinical diagnosis of tumors, it is useful to mine profiles for informative genes with definite biological meanings and to build robust classifiers with high precision. In this study, we developed a new method for tumor-gene selection, the Chi-square test-based integrated rank gene and direct classifier (χ(2)-IRG-DC). First, we obtained the weighted integrated rank of gene importance from chi-square tests of single and pairwise gene interactions. Then, we sequentially introduced the ranked genes and removed redundant genes by using leave-one-out cross-validation of the chi-square test-based Direct Classifier (χ(2)-DC) within the training set to obtain informative genes. Finally, we determined the accuracy of independent test data by utilizing the genes obtained above with χ(2)-DC. Furthermore, we analyzed the robustness of χ(2)-IRG-DC by comparing the generalization performance of different models, the efficiency of different feature-selection methods, and the accuracy of different classifiers. An independent test of ten multiclass tumor gene-expression datasets showed that χ(2)-IRG-DC could efficiently control overfitting and had higher generalization performance. The informative genes selected by χ(2)-IRG-DC could dramatically improve the independent test precision of other classifiers; meanwhile, the informative genes selected by other feature selection methods also had good performance in χ(2)-DC.
authors.affiliation: Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Changsha 410128, China ; College of Information Science and Technology, Hunan Agricultural University, Changsha 410128, China ; Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Changsha 410128, China.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Changsha 410128, China ; Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Changsha 410128, China.
authors.forename: Lanzhi
authors.initials: L
authors.lastname: Li
authors.affiliation: College of Information Science and Technology, Hunan Agricultural University, Changsha 410128, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Luo
authors.affiliation: Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Changsha 410128, China ; Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Changsha 410128, China.
authors.forename: Congwei
authors.initials: C
authors.lastname: Sun
authors.affiliation: Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Changsha 410128, China ; Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Changsha 410128, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Changsha 410128, China ; Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Changsha 410128, China.
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Dai
authors.affiliation: Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Changsha 410128, China ; Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect Pests, Changsha 410128, China.
authors.forename: Zheming
authors.initials: Z
authors.lastname: Yuan
mesh_terms: D000465:Algorithms; D004843:Epistasis, Genetic; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D006801:Humans; D008962:Models, Theoretical; D009363:Neoplasm Proteins / Q000096:biosynthesis*; D009369:Neoplasms / Q000235:genetics*; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods
chemical_list: D009363:Neoplasm Proteins