Fig. 3
A and B Comparison of three intermediate GTHC/NGTHCs analyzed by PCA with the 12 previously presented genes. We analyzed 23 chemicals plus three intermediate GHCs/NGTHCs, a total of 26 chemicals, 78 points, analyzed by PCA with 12 previously presented genes [29] at 24 h after a single administration and a total of 22 chemicals, 63 points, at 29 days after repeated administrations. The gene expression profile (log2) was calculated: the mean of each control group was calculated as 0 (log2), and ratio (exp/cont) (log2) was calculated (Appendix C.1 for 24 h and Appendix C.3 for 29 days). These numerical values were analyzed by PCA (Appendix C.2 for 24 h and Appendix C.4 for 29 days). At 24 h after a single administration, The PCA result shows a clear separation of five typical GTHCs from seven typical NGTHCs and 11 NGTNHCs by PCA with PC1, where GTHCs exhibit PC1 below –0.381 (DEN-low, PC1: −0.381, PC2: −0.822), and NGTHCs and NGTHCs exhibit PC1 above −0.130 (NGTHC, FEN-high, PC1: −0.13, PC2: 3.184) (Appendix C.2). Speaking of the three intermediate GTHC/NGTHCs (MCT: □, MP: △, and TAA: 〇), MP-high (PC1: −0.941, PC2: −0.472) and TAA-high (PC1: −3.04, PC2: −0.869) are in the GTHCs area. MCT-high (PC1: −0.109, PC2: −0.353) and TAA-middle (PC1: −0.024, PC2: −1.236) are in the intermediate area. MCT-low (PCA: 1.688, PC2: −0.149), MCT-middle (PC1: 1.149, PC2: −0.489), MP-low (PC1: 1.702, PC2: −0.059), MP-middle (PC1:1.324, PC2: −0.618), and TAA-low (PC1: 1.205, PC2: −0.671) are in the NGTHCs and NGTNHCs area. The analysis with12 genotoxic marker genes are similar to that with four genotoxic marker genes [Fig. 2(A)]. At 29 days after repeated administration, Fig. 3(B) demonstrates the discrimination of two GTHCs from seven NGTHCs and 10 NGTNHCs with PC1 by PCA, where GTHCs exhibit PC1 below −3.729 (DEN-low, PC1: −3.729, PC2: −1.776), and NGTHCs and NGTNHCs exhibit PC1 above −0.084 (PHE-low, PC1: −0.084, PC2: −1.015) (Appendix C.4). Three intermediate GTHC/NGTHCs (MCT: □, MP: △, and TAA: 〇), MCT-middle (PC1: −4.873, PC2: −1.08), MP-high (PC1: −7.093, PC2: 3.554), TAA-middle (PC1: −4.502, PC2: −1.021), and TAA-high (PC1: −6.931, PC2: 2.398) are in the GTHCs area. MCT-low (PC1: −2.402, PC2: −1.693), MP-middle (PC1: −1.322, PC2: 0.371), and TAA-low (PC1: −1.718, PC2: −0.155) are in the intermediate area between GTHCs and NGTHCs plus NGTNHCs. Only MP-low (PC1: 0.565, PC2: −0.792) is in the NGTHCs and NGTNHCs area. The results of an analysis with 12 genotoxic marker genes [Fig. 3(B)] are similar to those with four genotoxic marker genes [Fig. 2(B)]